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ccb88a689e
ndk-busybox/shell/ash.c
Denys Vlasenko 599ae1eb9f shell: consolidate builtin_foo.? into shell_common.?; delete obsolete shells 
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2010-05-23 17:49:50 +02:00

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/* vi: set sw=4 ts=4: */
/*
* ash shell port for busybox
*
* This code is derived from software contributed to Berkeley by
* Kenneth Almquist.
*
* Original BSD copyright notice is retained at the end of this file.
*
* Copyright (c) 1989, 1991, 1993, 1994
* The Regents of the University of California. All rights reserved.
*
* Copyright (c) 1997-2005 Herbert Xu <herbert@gondor.apana.org.au>
* was re-ported from NetBSD and debianized.
*
* Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
*/
/*
* The following should be set to reflect the type of system you have:
* JOBS -> 1 if you have Berkeley job control, 0 otherwise.
* define SYSV if you are running under System V.
* define DEBUG=1 to compile in debugging ('set -o debug' to turn on)
* define DEBUG=2 to compile in and turn on debugging.
*
* When debugging is on, debugging info will be written to ./trace and
* a quit signal will generate a core dump.
*/
#define DEBUG 0
/* Tweak debug output verbosity here */
#define DEBUG_TIME 0
#define DEBUG_PID 1
#define DEBUG_SIG 1
#define PROFILE 0
#define JOBS ENABLE_ASH_JOB_CONTROL
#if DEBUG
# ifndef _GNU_SOURCE
# define _GNU_SOURCE
# endif
#endif
#include "busybox.h" /* for applet_names */
#include <paths.h>
#include <setjmp.h>
#include <fnmatch.h>
#include "shell_common.h"
#include "math.h"
#if ENABLE_ASH_RANDOM_SUPPORT
# include "random.h"
#else
# define CLEAR_RANDOM_T(rnd) ((void)0)
#endif
#define SKIP_definitions 1
#include "applet_tables.h"
#undef SKIP_definitions
#if NUM_APPLETS == 1
/* STANDALONE does not make sense, and won't compile */
# undef CONFIG_FEATURE_SH_STANDALONE
# undef ENABLE_FEATURE_SH_STANDALONE
# undef IF_FEATURE_SH_STANDALONE
# undef IF_NOT_FEATURE_SH_STANDALONE
# define ENABLE_FEATURE_SH_STANDALONE 0
# define IF_FEATURE_SH_STANDALONE(...)
# define IF_NOT_FEATURE_SH_STANDALONE(...) __VA_ARGS__
#endif
#ifndef PIPE_BUF
# define PIPE_BUF 4096 /* amount of buffering in a pipe */
#endif
#if !BB_MMU
# error "Do not even bother, ash will not run on NOMMU machine"
#endif
/* ============ Hash table sizes. Configurable. */
#define VTABSIZE 39
#define ATABSIZE 39
#define CMDTABLESIZE 31 /* should be prime */
/* ============ Shell options */
static const char *const optletters_optnames[] = {
"e" "errexit",
"f" "noglob",
"I" "ignoreeof",
"i" "interactive",
"m" "monitor",
"n" "noexec",
"s" "stdin",
"x" "xtrace",
"v" "verbose",
"C" "noclobber",
"a" "allexport",
"b" "notify",
"u" "nounset",
"\0" "vi"
#if ENABLE_ASH_BASH_COMPAT
,"\0" "pipefail"
#endif
#if DEBUG
,"\0" "nolog"
,"\0" "debug"
#endif
};
#define optletters(n) optletters_optnames[n][0]
#define optnames(n) (optletters_optnames[n] + 1)
enum { NOPTS = ARRAY_SIZE(optletters_optnames) };
/* ============ Misc data */
static const char homestr[] ALIGN1 = "HOME";
static const char snlfmt[] ALIGN1 = "%s\n";
static const char msg_illnum[] ALIGN1 = "Illegal number: %s";
/*
* We enclose jmp_buf in a structure so that we can declare pointers to
* jump locations. The global variable handler contains the location to
* jump to when an exception occurs, and the global variable exception_type
* contains a code identifying the exception. To implement nested
* exception handlers, the user should save the value of handler on entry
* to an inner scope, set handler to point to a jmploc structure for the
* inner scope, and restore handler on exit from the scope.
*/
struct jmploc {
jmp_buf loc;
};
struct globals_misc {
/* pid of main shell */
int rootpid;
/* shell level: 0 for the main shell, 1 for its children, and so on */
int shlvl;
#define rootshell (!shlvl)
char *minusc; /* argument to -c option */
char *curdir; // = nullstr; /* current working directory */
char *physdir; // = nullstr; /* physical working directory */
char *arg0; /* value of $0 */
struct jmploc *exception_handler;
volatile int suppress_int; /* counter */
volatile /*sig_atomic_t*/ smallint pending_int; /* 1 = got SIGINT */
/* last pending signal */
volatile /*sig_atomic_t*/ smallint pending_sig;
smallint exception_type; /* kind of exception (0..5) */
/* exceptions */
#define EXINT 0 /* SIGINT received */
#define EXERROR 1 /* a generic error */
#define EXSHELLPROC 2 /* execute a shell procedure */
#define EXEXEC 3 /* command execution failed */
#define EXEXIT 4 /* exit the shell */
#define EXSIG 5 /* trapped signal in wait(1) */
smallint isloginsh;
char nullstr[1]; /* zero length string */
char optlist[NOPTS];
#define eflag optlist[0]
#define fflag optlist[1]
#define Iflag optlist[2]
#define iflag optlist[3]
#define mflag optlist[4]
#define nflag optlist[5]
#define sflag optlist[6]
#define xflag optlist[7]
#define vflag optlist[8]
#define Cflag optlist[9]
#define aflag optlist[10]
#define bflag optlist[11]
#define uflag optlist[12]
#define viflag optlist[13]
#if ENABLE_ASH_BASH_COMPAT
# define pipefail optlist[14]
#else
# define pipefail 0
#endif
#if DEBUG
# define nolog optlist[14 + ENABLE_ASH_BASH_COMPAT]
# define debug optlist[15 + ENABLE_ASH_BASH_COMPAT]
#endif
/* trap handler commands */
/*
* Sigmode records the current value of the signal handlers for the various
* modes. A value of zero means that the current handler is not known.
* S_HARD_IGN indicates that the signal was ignored on entry to the shell.
*/
char sigmode[NSIG - 1];
#define S_DFL 1 /* default signal handling (SIG_DFL) */
#define S_CATCH 2 /* signal is caught */
#define S_IGN 3 /* signal is ignored (SIG_IGN) */
#define S_HARD_IGN 4 /* signal is ignored permenantly */
/* indicates specified signal received */
uint8_t gotsig[NSIG - 1]; /* offset by 1: "signal" 0 is meaningless */
uint8_t may_have_traps; /* 0: definitely no traps are set, 1: some traps may be set */
char *trap[NSIG];
char **trap_ptr; /* used only by "trap hack" */
/* Rarely referenced stuff */
#if ENABLE_ASH_RANDOM_SUPPORT
random_t random_gen;
#endif
pid_t backgndpid; /* pid of last background process */
smallint job_warning; /* user was warned about stopped jobs (can be 2, 1 or 0). */
};
extern struct globals_misc *const ash_ptr_to_globals_misc;
#define G_misc (*ash_ptr_to_globals_misc)
#define rootpid (G_misc.rootpid )
#define shlvl (G_misc.shlvl )
#define minusc (G_misc.minusc )
#define curdir (G_misc.curdir )
#define physdir (G_misc.physdir )
#define arg0 (G_misc.arg0 )
#define exception_handler (G_misc.exception_handler)
#define exception_type (G_misc.exception_type )
#define suppress_int (G_misc.suppress_int )
#define pending_int (G_misc.pending_int )
#define pending_sig (G_misc.pending_sig )
#define isloginsh (G_misc.isloginsh )
#define nullstr (G_misc.nullstr )
#define optlist (G_misc.optlist )
#define sigmode (G_misc.sigmode )
#define gotsig (G_misc.gotsig )
#define may_have_traps (G_misc.may_have_traps )
#define trap (G_misc.trap )
#define trap_ptr (G_misc.trap_ptr )
#define random_gen (G_misc.random_gen )
#define backgndpid (G_misc.backgndpid )
#define job_warning (G_misc.job_warning)
#define INIT_G_misc() do { \
(*(struct globals_misc**)&ash_ptr_to_globals_misc) = xzalloc(sizeof(G_misc)); \
barrier(); \
curdir = nullstr; \
physdir = nullstr; \
trap_ptr = trap; \
} while (0)
/* ============ DEBUG */
#if DEBUG
static void trace_printf(const char *fmt, ...);
static void trace_vprintf(const char *fmt, va_list va);
# define TRACE(param) trace_printf param
# define TRACEV(param) trace_vprintf param
# define close(fd) do { \
int dfd = (fd); \
if (close(dfd) < 0) \
bb_error_msg("bug on %d: closing %d(0x%x)", \
__LINE__, dfd, dfd); \
} while (0)
#else
# define TRACE(param)
# define TRACEV(param)
#endif
/* ============ Utility functions */
#define xbarrier() do { __asm__ __volatile__ ("": : :"memory"); } while (0)
static int isdigit_str9(const char *str)
{
int maxlen = 9 + 1; /* max 9 digits: 999999999 */
while (--maxlen && isdigit(*str))
str++;
return (*str == '\0');
}
/* ============ Interrupts / exceptions */
/*
* These macros allow the user to suspend the handling of interrupt signals
* over a period of time. This is similar to SIGHOLD or to sigblock, but
* much more efficient and portable. (But hacking the kernel is so much
* more fun than worrying about efficiency and portability. :-))
*/
#define INT_OFF do { \
suppress_int++; \
xbarrier(); \
} while (0)
/*
* Called to raise an exception. Since C doesn't include exceptions, we
* just do a longjmp to the exception handler. The type of exception is
* stored in the global variable "exception_type".
*/
static void raise_exception(int) NORETURN;
static void
raise_exception(int e)
{
#if DEBUG
if (exception_handler == NULL)
abort();
#endif
INT_OFF;
exception_type = e;
longjmp(exception_handler->loc, 1);
}
#if DEBUG
#define raise_exception(e) do { \
TRACE(("raising exception %d on line %d\n", (e), __LINE__)); \
raise_exception(e); \
} while (0)
#endif
/*
* Called from trap.c when a SIGINT is received. (If the user specifies
* that SIGINT is to be trapped or ignored using the trap builtin, then
* this routine is not called.) Suppressint is nonzero when interrupts
* are held using the INT_OFF macro. (The test for iflag is just
* defensive programming.)
*/
static void raise_interrupt(void) NORETURN;
static void
raise_interrupt(void)
{
int ex_type;
pending_int = 0;
/* Signal is not automatically unmasked after it is raised,
* do it ourself - unmask all signals */
sigprocmask_allsigs(SIG_UNBLOCK);
/* pending_sig = 0; - now done in signal_handler() */
ex_type = EXSIG;
if (gotsig[SIGINT - 1] && !trap[SIGINT]) {
if (!(rootshell && iflag)) {
/* Kill ourself with SIGINT */
signal(SIGINT, SIG_DFL);
raise(SIGINT);
}
ex_type = EXINT;
}
raise_exception(ex_type);
/* NOTREACHED */
}
#if DEBUG
#define raise_interrupt() do { \
TRACE(("raising interrupt on line %d\n", __LINE__)); \
raise_interrupt(); \
} while (0)
#endif
static IF_ASH_OPTIMIZE_FOR_SIZE(inline) void
int_on(void)
{
xbarrier();
if (--suppress_int == 0 && pending_int) {
raise_interrupt();
}
}
#define INT_ON int_on()
static IF_ASH_OPTIMIZE_FOR_SIZE(inline) void
force_int_on(void)
{
xbarrier();
suppress_int = 0;
if (pending_int)
raise_interrupt();
}
#define FORCE_INT_ON force_int_on()
#define SAVE_INT(v) ((v) = suppress_int)
#define RESTORE_INT(v) do { \
xbarrier(); \
suppress_int = (v); \
if (suppress_int == 0 && pending_int) \
raise_interrupt(); \
} while (0)
/* ============ Stdout/stderr output */
static void
outstr(const char *p, FILE *file)
{
INT_OFF;
fputs(p, file);
INT_ON;
}
static void
flush_stdout_stderr(void)
{
INT_OFF;
fflush_all();
INT_ON;
}
static void
outcslow(int c, FILE *dest)
{
INT_OFF;
putc(c, dest);
fflush(dest);
INT_ON;
}
static int out1fmt(const char *, ...) __attribute__((__format__(__printf__,1,2)));
static int
out1fmt(const char *fmt, ...)
{
va_list ap;
int r;
INT_OFF;
va_start(ap, fmt);
r = vprintf(fmt, ap);
va_end(ap);
INT_ON;
return r;
}
static int fmtstr(char *, size_t, const char *, ...) __attribute__((__format__(__printf__,3,4)));
static int
fmtstr(char *outbuf, size_t length, const char *fmt, ...)
{
va_list ap;
int ret;
va_start(ap, fmt);
INT_OFF;
ret = vsnprintf(outbuf, length, fmt, ap);
va_end(ap);
INT_ON;
return ret;
}
static void
out1str(const char *p)
{
outstr(p, stdout);
}
static void
out2str(const char *p)
{
outstr(p, stderr);
flush_stdout_stderr();
}
/* ============ Parser structures */
/* control characters in argument strings */
#define CTL_FIRST CTLESC
#define CTLESC ((unsigned char)'\201') /* escape next character */
#define CTLVAR ((unsigned char)'\202') /* variable defn */
#define CTLENDVAR ((unsigned char)'\203')
#define CTLBACKQ ((unsigned char)'\204')
#define CTLQUOTE 01 /* ored with CTLBACKQ code if in quotes */
/* CTLBACKQ | CTLQUOTE == '\205' */
#define CTLARI ((unsigned char)'\206') /* arithmetic expression */
#define CTLENDARI ((unsigned char)'\207')
#define CTLQUOTEMARK ((unsigned char)'\210')
#define CTL_LAST CTLQUOTEMARK
/* variable substitution byte (follows CTLVAR) */
#define VSTYPE 0x0f /* type of variable substitution */
#define VSNUL 0x10 /* colon--treat the empty string as unset */
#define VSQUOTE 0x80 /* inside double quotes--suppress splitting */
/* values of VSTYPE field */
#define VSNORMAL 0x1 /* normal variable: $var or ${var} */
#define VSMINUS 0x2 /* ${var-text} */
#define VSPLUS 0x3 /* ${var+text} */
#define VSQUESTION 0x4 /* ${var?message} */
#define VSASSIGN 0x5 /* ${var=text} */
#define VSTRIMRIGHT 0x6 /* ${var%pattern} */
#define VSTRIMRIGHTMAX 0x7 /* ${var%%pattern} */
#define VSTRIMLEFT 0x8 /* ${var#pattern} */
#define VSTRIMLEFTMAX 0x9 /* ${var##pattern} */
#define VSLENGTH 0xa /* ${#var} */
#if ENABLE_ASH_BASH_COMPAT
#define VSSUBSTR 0xc /* ${var:position:length} */
#define VSREPLACE 0xd /* ${var/pattern/replacement} */
#define VSREPLACEALL 0xe /* ${var//pattern/replacement} */
#endif
static const char dolatstr[] ALIGN1 = {
CTLVAR, VSNORMAL|VSQUOTE, '@', '=', '\0'
};
#define NCMD 0
#define NPIPE 1
#define NREDIR 2
#define NBACKGND 3
#define NSUBSHELL 4
#define NAND 5
#define NOR 6
#define NSEMI 7
#define NIF 8
#define NWHILE 9
#define NUNTIL 10
#define NFOR 11
#define NCASE 12
#define NCLIST 13
#define NDEFUN 14
#define NARG 15
#define NTO 16
#if ENABLE_ASH_BASH_COMPAT
#define NTO2 17
#endif
#define NCLOBBER 18
#define NFROM 19
#define NFROMTO 20
#define NAPPEND 21
#define NTOFD 22
#define NFROMFD 23
#define NHERE 24
#define NXHERE 25
#define NNOT 26
#define N_NUMBER 27
union node;
struct ncmd {
smallint type; /* Nxxxx */
union node *assign;
union node *args;
union node *redirect;
};
struct npipe {
smallint type;
smallint pipe_backgnd;
struct nodelist *cmdlist;
};
struct nredir {
smallint type;
union node *n;
union node *redirect;
};
struct nbinary {
smallint type;
union node *ch1;
union node *ch2;
};
struct nif {
smallint type;
union node *test;
union node *ifpart;
union node *elsepart;
};
struct nfor {
smallint type;
union node *args;
union node *body;
char *var;
};
struct ncase {
smallint type;
union node *expr;
union node *cases;
};
struct nclist {
smallint type;
union node *next;
union node *pattern;
union node *body;
};
struct narg {
smallint type;
union node *next;
char *text;
struct nodelist *backquote;
};
/* nfile and ndup layout must match!
* NTOFD (>&fdnum) uses ndup structure, but we may discover mid-flight
* that it is actually NTO2 (>&file), and change its type.
*/
struct nfile {
smallint type;
union node *next;
int fd;
int _unused_dupfd;
union node *fname;
char *expfname;
};
struct ndup {
smallint type;
union node *next;
int fd;
int dupfd;
union node *vname;
char *_unused_expfname;
};
struct nhere {
smallint type;
union node *next;
int fd;
union node *doc;
};
struct nnot {
smallint type;
union node *com;
};
union node {
smallint type;
struct ncmd ncmd;
struct npipe npipe;
struct nredir nredir;
struct nbinary nbinary;
struct nif nif;
struct nfor nfor;
struct ncase ncase;
struct nclist nclist;
struct narg narg;
struct nfile nfile;
struct ndup ndup;
struct nhere nhere;
struct nnot nnot;
};
/*
* NODE_EOF is returned by parsecmd when it encounters an end of file.
* It must be distinct from NULL.
*/
#define NODE_EOF ((union node *) -1L)
struct nodelist {
struct nodelist *next;
union node *n;
};
struct funcnode {
int count;
union node n;
};
/*
* Free a parse tree.
*/
static void
freefunc(struct funcnode *f)
{
if (f && --f->count < 0)
free(f);
}
/* ============ Debugging output */
#if DEBUG
static FILE *tracefile;
static void
trace_printf(const char *fmt, ...)
{
va_list va;
if (debug != 1)
return;
if (DEBUG_TIME)
fprintf(tracefile, "%u ", (int) time(NULL));
if (DEBUG_PID)
fprintf(tracefile, "[%u] ", (int) getpid());
if (DEBUG_SIG)
fprintf(tracefile, "pending s:%d i:%d(supp:%d) ", pending_sig, pending_int, suppress_int);
va_start(va, fmt);
vfprintf(tracefile, fmt, va);
va_end(va);
}
static void
trace_vprintf(const char *fmt, va_list va)
{
if (debug != 1)
return;
if (DEBUG_TIME)
fprintf(tracefile, "%u ", (int) time(NULL));
if (DEBUG_PID)
fprintf(tracefile, "[%u] ", (int) getpid());
if (DEBUG_SIG)
fprintf(tracefile, "pending s:%d i:%d(supp:%d) ", pending_sig, pending_int, suppress_int);
vfprintf(tracefile, fmt, va);
}
static void
trace_puts(const char *s)
{
if (debug != 1)
return;
fputs(s, tracefile);
}
static void
trace_puts_quoted(char *s)
{
char *p;
char c;
if (debug != 1)
return;
putc('"', tracefile);
for (p = s; *p; p++) {
switch ((unsigned char)*p) {
case '\n': c = 'n'; goto backslash;
case '\t': c = 't'; goto backslash;
case '\r': c = 'r'; goto backslash;
case '\"': c = '\"'; goto backslash;
case '\\': c = '\\'; goto backslash;
case CTLESC: c = 'e'; goto backslash;
case CTLVAR: c = 'v'; goto backslash;
case CTLVAR+CTLQUOTE: c = 'V'; goto backslash;
case CTLBACKQ: c = 'q'; goto backslash;
case CTLBACKQ+CTLQUOTE: c = 'Q'; goto backslash;
backslash:
putc('\\', tracefile);
putc(c, tracefile);
break;
default:
if (*p >= ' ' && *p <= '~')
putc(*p, tracefile);
else {
putc('\\', tracefile);
putc((*p >> 6) & 03, tracefile);
putc((*p >> 3) & 07, tracefile);
putc(*p & 07, tracefile);
}
break;
}
}
putc('"', tracefile);
}
static void
trace_puts_args(char **ap)
{
if (debug != 1)
return;
if (!*ap)
return;
while (1) {
trace_puts_quoted(*ap);
if (!*++ap) {
putc('\n', tracefile);
break;
}
putc(' ', tracefile);
}
}
static void
opentrace(void)
{
char s[100];
#ifdef O_APPEND
int flags;
#endif
if (debug != 1) {
if (tracefile)
fflush(tracefile);
/* leave open because libedit might be using it */
return;
}
strcpy(s, "./trace");
if (tracefile) {
if (!freopen(s, "a", tracefile)) {
fprintf(stderr, "Can't re-open %s\n", s);
debug = 0;
return;
}
} else {
tracefile = fopen(s, "a");
if (tracefile == NULL) {
fprintf(stderr, "Can't open %s\n", s);
debug = 0;
return;
}
}
#ifdef O_APPEND
flags = fcntl(fileno(tracefile), F_GETFL);
if (flags >= 0)
fcntl(fileno(tracefile), F_SETFL, flags | O_APPEND);
#endif
setlinebuf(tracefile);
fputs("\nTracing started.\n", tracefile);
}
static void
indent(int amount, char *pfx, FILE *fp)
{
int i;
for (i = 0; i < amount; i++) {
if (pfx && i == amount - 1)
fputs(pfx, fp);
putc('\t', fp);
}
}
/* little circular references here... */
static void shtree(union node *n, int ind, char *pfx, FILE *fp);
static void
sharg(union node *arg, FILE *fp)
{
char *p;
struct nodelist *bqlist;
unsigned char subtype;
if (arg->type != NARG) {
out1fmt("<node type %d>\n", arg->type);
abort();
}
bqlist = arg->narg.backquote;
for (p = arg->narg.text; *p; p++) {
switch ((unsigned char)*p) {
case CTLESC:
putc(*++p, fp);
break;
case CTLVAR:
putc('$', fp);
putc('{', fp);
subtype = *++p;
if (subtype == VSLENGTH)
putc('#', fp);
while (*p != '=')
putc(*p++, fp);
if (subtype & VSNUL)
putc(':', fp);
switch (subtype & VSTYPE) {
case VSNORMAL:
putc('}', fp);
break;
case VSMINUS:
putc('-', fp);
break;
case VSPLUS:
putc('+', fp);
break;
case VSQUESTION:
putc('?', fp);
break;
case VSASSIGN:
putc('=', fp);
break;
case VSTRIMLEFT:
putc('#', fp);
break;
case VSTRIMLEFTMAX:
putc('#', fp);
putc('#', fp);
break;
case VSTRIMRIGHT:
putc('%', fp);
break;
case VSTRIMRIGHTMAX:
putc('%', fp);
putc('%', fp);
break;
case VSLENGTH:
break;
default:
out1fmt("<subtype %d>", subtype);
}
break;
case CTLENDVAR:
putc('}', fp);
break;
case CTLBACKQ:
case CTLBACKQ|CTLQUOTE:
putc('$', fp);
putc('(', fp);
shtree(bqlist->n, -1, NULL, fp);
putc(')', fp);
break;
default:
putc(*p, fp);
break;
}
}
}
static void
shcmd(union node *cmd, FILE *fp)
{
union node *np;
int first;
const char *s;
int dftfd;
first = 1;
for (np = cmd->ncmd.args; np; np = np->narg.next) {
if (!first)
putc(' ', fp);
sharg(np, fp);
first = 0;
}
for (np = cmd->ncmd.redirect; np; np = np->nfile.next) {
if (!first)
putc(' ', fp);
dftfd = 0;
switch (np->nfile.type) {
case NTO: s = ">>"+1; dftfd = 1; break;
case NCLOBBER: s = ">|"; dftfd = 1; break;
case NAPPEND: s = ">>"; dftfd = 1; break;
#if ENABLE_ASH_BASH_COMPAT
case NTO2:
#endif
case NTOFD: s = ">&"; dftfd = 1; break;
case NFROM: s = "<"; break;
case NFROMFD: s = "<&"; break;
case NFROMTO: s = "<>"; break;
default: s = "*error*"; break;
}
if (np->nfile.fd != dftfd)
fprintf(fp, "%d", np->nfile.fd);
fputs(s, fp);
if (np->nfile.type == NTOFD || np->nfile.type == NFROMFD) {
fprintf(fp, "%d", np->ndup.dupfd);
} else {
sharg(np->nfile.fname, fp);
}
first = 0;
}
}
static void
shtree(union node *n, int ind, char *pfx, FILE *fp)
{
struct nodelist *lp;
const char *s;
if (n == NULL)
return;
indent(ind, pfx, fp);
if (n == NODE_EOF) {
fputs("<EOF>", fp);
return;
}
switch (n->type) {
case NSEMI:
s = "; ";
goto binop;
case NAND:
s = " && ";
goto binop;
case NOR:
s = " || ";
binop:
shtree(n->nbinary.ch1, ind, NULL, fp);
/* if (ind < 0) */
fputs(s, fp);
shtree(n->nbinary.ch2, ind, NULL, fp);
break;
case NCMD:
shcmd(n, fp);
if (ind >= 0)
putc('\n', fp);
break;
case NPIPE:
for (lp = n->npipe.cmdlist; lp; lp = lp->next) {
shtree(lp->n, 0, NULL, fp);
if (lp->next)
fputs(" | ", fp);
}
if (n->npipe.pipe_backgnd)
fputs(" &", fp);
if (ind >= 0)
putc('\n', fp);
break;
default:
fprintf(fp, "<node type %d>", n->type);
if (ind >= 0)
putc('\n', fp);
break;
}
}
static void
showtree(union node *n)
{
trace_puts("showtree called\n");
shtree(n, 1, NULL, stderr);
}
#endif /* DEBUG */
/* ============ Parser data */
/*
* ash_vmsg() needs parsefile->fd, hence parsefile definition is moved up.
*/
struct strlist {
struct strlist *next;
char *text;
};
struct alias;
struct strpush {
struct strpush *prev; /* preceding string on stack */
char *prev_string;
int prev_left_in_line;
#if ENABLE_ASH_ALIAS
struct alias *ap; /* if push was associated with an alias */
#endif
char *string; /* remember the string since it may change */
};
struct parsefile {
struct parsefile *prev; /* preceding file on stack */
int linno; /* current line */
int fd; /* file descriptor (or -1 if string) */
int left_in_line; /* number of chars left in this line */
int left_in_buffer; /* number of chars left in this buffer past the line */
char *next_to_pgetc; /* next char in buffer */
char *buf; /* input buffer */
struct strpush *strpush; /* for pushing strings at this level */
struct strpush basestrpush; /* so pushing one is fast */
};
static struct parsefile basepf; /* top level input file */
static struct parsefile *g_parsefile = &basepf; /* current input file */
static int startlinno; /* line # where last token started */
static char *commandname; /* currently executing command */
static struct strlist *cmdenviron; /* environment for builtin command */
static uint8_t exitstatus; /* exit status of last command */
/* ============ Message printing */
static void
ash_vmsg(const char *msg, va_list ap)
{
fprintf(stderr, "%s: ", arg0);
if (commandname) {
if (strcmp(arg0, commandname))
fprintf(stderr, "%s: ", commandname);
if (!iflag || g_parsefile->fd)
fprintf(stderr, "line %d: ", startlinno);
}
vfprintf(stderr, msg, ap);
outcslow('\n', stderr);
}
/*
* Exverror is called to raise the error exception. If the second argument
* is not NULL then error prints an error message using printf style
* formatting. It then raises the error exception.
*/
static void ash_vmsg_and_raise(int, const char *, va_list) NORETURN;
static void
ash_vmsg_and_raise(int cond, const char *msg, va_list ap)
{
#if DEBUG
if (msg) {
TRACE(("ash_vmsg_and_raise(%d, \"", cond));
TRACEV((msg, ap));
TRACE(("\") pid=%d\n", getpid()));
} else
TRACE(("ash_vmsg_and_raise(%d, NULL) pid=%d\n", cond, getpid()));
if (msg)
#endif
ash_vmsg(msg, ap);
flush_stdout_stderr();
raise_exception(cond);
/* NOTREACHED */
}
static void ash_msg_and_raise_error(const char *, ...) NORETURN;
static void
ash_msg_and_raise_error(const char *msg, ...)
{
va_list ap;
va_start(ap, msg);
ash_vmsg_and_raise(EXERROR, msg, ap);
/* NOTREACHED */
va_end(ap);
}
static void raise_error_syntax(const char *) NORETURN;
static void
raise_error_syntax(const char *msg)
{
ash_msg_and_raise_error("syntax error: %s", msg);
/* NOTREACHED */
}
static void ash_msg_and_raise(int, const char *, ...) NORETURN;
static void
ash_msg_and_raise(int cond, const char *msg, ...)
{
va_list ap;
va_start(ap, msg);
ash_vmsg_and_raise(cond, msg, ap);
/* NOTREACHED */
va_end(ap);
}
/*
* error/warning routines for external builtins
*/
static void
ash_msg(const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
ash_vmsg(fmt, ap);
va_end(ap);
}
/*
* Return a string describing an error. The returned string may be a
* pointer to a static buffer that will be overwritten on the next call.
* Action describes the operation that got the error.
*/
static const char *
errmsg(int e, const char *em)
{
if (e == ENOENT || e == ENOTDIR) {
return em;
}
return strerror(e);
}
/* ============ Memory allocation */
#if 0
/* I consider these wrappers nearly useless:
* ok, they return you to nearest exception handler, but
* how much memory do you leak in the process, making
* memory starvation worse?
*/
static void *
ckrealloc(void * p, size_t nbytes)
{
p = realloc(p, nbytes);
if (!p)
ash_msg_and_raise_error(bb_msg_memory_exhausted);
return p;
}
static void *
ckmalloc(size_t nbytes)
{
return ckrealloc(NULL, nbytes);
}
static void *
ckzalloc(size_t nbytes)
{
return memset(ckmalloc(nbytes), 0, nbytes);
}
static char *
ckstrdup(const char *s)
{
char *p = strdup(s);
if (!p)
ash_msg_and_raise_error(bb_msg_memory_exhausted);
return p;
}
#else
/* Using bbox equivalents. They exit if out of memory */
# define ckrealloc xrealloc
# define ckmalloc xmalloc
# define ckzalloc xzalloc
# define ckstrdup xstrdup
#endif
/*
* It appears that grabstackstr() will barf with such alignments
* because stalloc() will return a string allocated in a new stackblock.
*/
#define SHELL_ALIGN(nbytes) (((nbytes) + SHELL_SIZE) & ~SHELL_SIZE)
enum {
/* Most machines require the value returned from malloc to be aligned
* in some way. The following macro will get this right
* on many machines. */
SHELL_SIZE = sizeof(union { int i; char *cp; double d; }) - 1,
/* Minimum size of a block */
MINSIZE = SHELL_ALIGN(504),
};
struct stack_block {
struct stack_block *prev;
char space[MINSIZE];
};
struct stackmark {
struct stack_block *stackp;
char *stacknxt;
size_t stacknleft;
struct stackmark *marknext;
};
struct globals_memstack {
struct stack_block *g_stackp; // = &stackbase;
struct stackmark *markp;
char *g_stacknxt; // = stackbase.space;
char *sstrend; // = stackbase.space + MINSIZE;
size_t g_stacknleft; // = MINSIZE;
int herefd; // = -1;
struct stack_block stackbase;
};
extern struct globals_memstack *const ash_ptr_to_globals_memstack;
#define G_memstack (*ash_ptr_to_globals_memstack)
#define g_stackp (G_memstack.g_stackp )
#define markp (G_memstack.markp )
#define g_stacknxt (G_memstack.g_stacknxt )
#define sstrend (G_memstack.sstrend )
#define g_stacknleft (G_memstack.g_stacknleft)
#define herefd (G_memstack.herefd )
#define stackbase (G_memstack.stackbase )
#define INIT_G_memstack() do { \
(*(struct globals_memstack**)&ash_ptr_to_globals_memstack) = xzalloc(sizeof(G_memstack)); \
barrier(); \
g_stackp = &stackbase; \
g_stacknxt = stackbase.space; \
g_stacknleft = MINSIZE; \
sstrend = stackbase.space + MINSIZE; \
herefd = -1; \
} while (0)
#define stackblock() ((void *)g_stacknxt)
#define stackblocksize() g_stacknleft
/*
* Parse trees for commands are allocated in lifo order, so we use a stack
* to make this more efficient, and also to avoid all sorts of exception
* handling code to handle interrupts in the middle of a parse.
*
* The size 504 was chosen because the Ultrix malloc handles that size
* well.
*/
static void *
stalloc(size_t nbytes)
{
char *p;
size_t aligned;
aligned = SHELL_ALIGN(nbytes);
if (aligned > g_stacknleft) {
size_t len;
size_t blocksize;
struct stack_block *sp;
blocksize = aligned;
if (blocksize < MINSIZE)
blocksize = MINSIZE;
len = sizeof(struct stack_block) - MINSIZE + blocksize;
if (len < blocksize)
ash_msg_and_raise_error(bb_msg_memory_exhausted);
INT_OFF;
sp = ckmalloc(len);
sp->prev = g_stackp;
g_stacknxt = sp->space;
g_stacknleft = blocksize;
sstrend = g_stacknxt + blocksize;
g_stackp = sp;
INT_ON;
}
p = g_stacknxt;
g_stacknxt += aligned;
g_stacknleft -= aligned;
return p;
}
static void *
stzalloc(size_t nbytes)
{
return memset(stalloc(nbytes), 0, nbytes);
}
static void
stunalloc(void *p)
{
#if DEBUG
if (!p || (g_stacknxt < (char *)p) || ((char *)p < g_stackp->space)) {
write(STDERR_FILENO, "stunalloc\n", 10);
abort();
}
#endif
g_stacknleft += g_stacknxt - (char *)p;
g_stacknxt = p;
}
/*
* Like strdup but works with the ash stack.
*/
static char *
ststrdup(const char *p)
{
size_t len = strlen(p) + 1;
return memcpy(stalloc(len), p, len);
}
static void
setstackmark(struct stackmark *mark)
{
mark->stackp = g_stackp;
mark->stacknxt = g_stacknxt;
mark->stacknleft = g_stacknleft;
mark->marknext = markp;
markp = mark;
}
static void
popstackmark(struct stackmark *mark)
{
struct stack_block *sp;
if (!mark->stackp)
return;
INT_OFF;
markp = mark->marknext;
while (g_stackp != mark->stackp) {
sp = g_stackp;
g_stackp = sp->prev;
free(sp);
}
g_stacknxt = mark->stacknxt;
g_stacknleft = mark->stacknleft;
sstrend = mark->stacknxt + mark->stacknleft;
INT_ON;
}
/*
* When the parser reads in a string, it wants to stick the string on the
* stack and only adjust the stack pointer when it knows how big the
* string is. Stackblock (defined in stack.h) returns a pointer to a block
* of space on top of the stack and stackblocklen returns the length of
* this block. Growstackblock will grow this space by at least one byte,
* possibly moving it (like realloc). Grabstackblock actually allocates the
* part of the block that has been used.
*/
static void
growstackblock(void)
{
size_t newlen;
newlen = g_stacknleft * 2;
if (newlen < g_stacknleft)
ash_msg_and_raise_error(bb_msg_memory_exhausted);
if (newlen < 128)
newlen += 128;
if (g_stacknxt == g_stackp->space && g_stackp != &stackbase) {
struct stack_block *oldstackp;
struct stackmark *xmark;
struct stack_block *sp;
struct stack_block *prevstackp;
size_t grosslen;
INT_OFF;
oldstackp = g_stackp;
sp = g_stackp;
prevstackp = sp->prev;
grosslen = newlen + sizeof(struct stack_block) - MINSIZE;
sp = ckrealloc(sp, grosslen);
sp->prev = prevstackp;
g_stackp = sp;
g_stacknxt = sp->space;
g_stacknleft = newlen;
sstrend = sp->space + newlen;
/*
* Stack marks pointing to the start of the old block
* must be relocated to point to the new block
*/
xmark = markp;
while (xmark != NULL && xmark->stackp == oldstackp) {
xmark->stackp = g_stackp;
xmark->stacknxt = g_stacknxt;
xmark->stacknleft = g_stacknleft;
xmark = xmark->marknext;
}
INT_ON;
} else {
char *oldspace = g_stacknxt;
size_t oldlen = g_stacknleft;
char *p = stalloc(newlen);
/* free the space we just allocated */
g_stacknxt = memcpy(p, oldspace, oldlen);
g_stacknleft += newlen;
}
}
static void
grabstackblock(size_t len)
{
len = SHELL_ALIGN(len);
g_stacknxt += len;
g_stacknleft -= len;
}
/*
* The following routines are somewhat easier to use than the above.
* The user declares a variable of type STACKSTR, which may be declared
* to be a register. The macro STARTSTACKSTR initializes things. Then
* the user uses the macro STPUTC to add characters to the string. In
* effect, STPUTC(c, p) is the same as *p++ = c except that the stack is
* grown as necessary. When the user is done, she can just leave the
* string there and refer to it using stackblock(). Or she can allocate
* the space for it using grabstackstr(). If it is necessary to allow
* someone else to use the stack temporarily and then continue to grow
* the string, the user should use grabstack to allocate the space, and
* then call ungrabstr(p) to return to the previous mode of operation.
*
* USTPUTC is like STPUTC except that it doesn't check for overflow.
* CHECKSTACKSPACE can be called before USTPUTC to ensure that there
* is space for at least one character.
*/
static void *
growstackstr(void)
{
size_t len = stackblocksize();
if (herefd >= 0 && len >= 1024) {
full_write(herefd, stackblock(), len);
return stackblock();
}
growstackblock();
return (char *)stackblock() + len;
}
/*
* Called from CHECKSTRSPACE.
*/
static char *
makestrspace(size_t newlen, char *p)
{
size_t len = p - g_stacknxt;
size_t size = stackblocksize();
for (;;) {
size_t nleft;
size = stackblocksize();
nleft = size - len;
if (nleft >= newlen)
break;
growstackblock();
}
return (char *)stackblock() + len;
}
static char *
stack_nputstr(const char *s, size_t n, char *p)
{
p = makestrspace(n, p);
p = (char *)memcpy(p, s, n) + n;
return p;
}
static char *
stack_putstr(const char *s, char *p)
{
return stack_nputstr(s, strlen(s), p);
}
static char *
_STPUTC(int c, char *p)
{
if (p == sstrend)
p = growstackstr();
*p++ = c;
return p;
}
#define STARTSTACKSTR(p) ((p) = stackblock())
#define STPUTC(c, p) ((p) = _STPUTC((c), (p)))
#define CHECKSTRSPACE(n, p) do { \
char *q = (p); \
size_t l = (n); \
size_t m = sstrend - q; \
if (l > m) \
(p) = makestrspace(l, q); \
} while (0)
#define USTPUTC(c, p) (*(p)++ = (c))
#define STACKSTRNUL(p) do { \
if ((p) == sstrend) \
(p) = growstackstr(); \
*(p) = '\0'; \
} while (0)
#define STUNPUTC(p) (--(p))
#define STTOPC(p) ((p)[-1])
#define STADJUST(amount, p) ((p) += (amount))
#define grabstackstr(p) stalloc((char *)(p) - (char *)stackblock())
#define ungrabstackstr(s, p) stunalloc(s)
#define stackstrend() ((void *)sstrend)
/* ============ String helpers */
/*
* prefix -- see if pfx is a prefix of string.
*/
static char *
prefix(const char *string, const char *pfx)
{
while (*pfx) {
if (*pfx++ != *string++)
return NULL;
}
return (char *) string;
}
/*
* Check for a valid number. This should be elsewhere.
*/
static int
is_number(const char *p)
{
do {
if (!isdigit(*p))
return 0;
} while (*++p != '\0');
return 1;
}
/*
* Convert a string of digits to an integer, printing an error message on
* failure.
*/
static int
number(const char *s)
{
if (!is_number(s))
ash_msg_and_raise_error(msg_illnum, s);
return atoi(s);
}
/*
* Produce a possibly single quoted string suitable as input to the shell.
* The return string is allocated on the stack.
*/
static char *
single_quote(const char *s)
{
char *p;
STARTSTACKSTR(p);
do {
char *q;
size_t len;
len = strchrnul(s, '\'') - s;
q = p = makestrspace(len + 3, p);
*q++ = '\'';
q = (char *)memcpy(q, s, len) + len;
*q++ = '\'';
s += len;
STADJUST(q - p, p);
if (*s != '\'')
break;
len = 0;
do len++; while (*++s == '\'');
q = p = makestrspace(len + 3, p);
*q++ = '"';
q = (char *)memcpy(q, s - len, len) + len;
*q++ = '"';
STADJUST(q - p, p);
} while (*s);
USTPUTC('\0', p);
return stackblock();
}
/* ============ nextopt */
static char **argptr; /* argument list for builtin commands */
static char *optionarg; /* set by nextopt (like getopt) */
static char *optptr; /* used by nextopt */
/*
* XXX - should get rid of. Have all builtins use getopt(3).
* The library getopt must have the BSD extension static variable
* "optreset", otherwise it can't be used within the shell safely.
*
* Standard option processing (a la getopt) for builtin routines.
* The only argument that is passed to nextopt is the option string;
* the other arguments are unnecessary. It returns the character,
* or '\0' on end of input.
*/
static int
nextopt(const char *optstring)
{
char *p;
const char *q;
char c;
p = optptr;
if (p == NULL || *p == '\0') {
/* We ate entire "-param", take next one */
p = *argptr;
if (p == NULL)
return '\0';
if (*p != '-')
return '\0';
if (*++p == '\0') /* just "-" ? */
return '\0';
argptr++;
if (LONE_DASH(p)) /* "--" ? */
return '\0';
/* p => next "-param" */
}
/* p => some option char in the middle of a "-param" */
c = *p++;
for (q = optstring; *q != c;) {
if (*q == '\0')
ash_msg_and_raise_error("illegal option -%c", c);
if (*++q == ':')
q++;
}
if (*++q == ':') {
if (*p == '\0') {
p = *argptr++;
if (p == NULL)
ash_msg_and_raise_error("no arg for -%c option", c);
}
optionarg = p;
p = NULL;
}
optptr = p;
return c;
}
/* ============ Shell variables */
/*
* The parsefile structure pointed to by the global variable parsefile
* contains information about the current file being read.
*/
struct shparam {
int nparam; /* # of positional parameters (without $0) */
#if ENABLE_ASH_GETOPTS
int optind; /* next parameter to be processed by getopts */
int optoff; /* used by getopts */
#endif
unsigned char malloced; /* if parameter list dynamically allocated */
char **p; /* parameter list */
};
/*
* Free the list of positional parameters.
*/
static void
freeparam(volatile struct shparam *param)
{
if (param->malloced) {
char **ap, **ap1;
ap = ap1 = param->p;
while (*ap)
free(*ap++);
free(ap1);
}
}
#if ENABLE_ASH_GETOPTS
static void FAST_FUNC getoptsreset(const char *value);
#endif
struct var {
struct var *next; /* next entry in hash list */
int flags; /* flags are defined above */
const char *text; /* name=value */
void (*func)(const char *) FAST_FUNC; /* function to be called when */
/* the variable gets set/unset */
};
struct localvar {
struct localvar *next; /* next local variable in list */
struct var *vp; /* the variable that was made local */
int flags; /* saved flags */
const char *text; /* saved text */
};
/* flags */
#define VEXPORT 0x01 /* variable is exported */
#define VREADONLY 0x02 /* variable cannot be modified */
#define VSTRFIXED 0x04 /* variable struct is statically allocated */
#define VTEXTFIXED 0x08 /* text is statically allocated */
#define VSTACK 0x10 /* text is allocated on the stack */
#define VUNSET 0x20 /* the variable is not set */
#define VNOFUNC 0x40 /* don't call the callback function */
#define VNOSET 0x80 /* do not set variable - just readonly test */
#define VNOSAVE 0x100 /* when text is on the heap before setvareq */
#if ENABLE_ASH_RANDOM_SUPPORT
# define VDYNAMIC 0x200 /* dynamic variable */
#else
# define VDYNAMIC 0
#endif
/* Need to be before varinit_data[] */
#if ENABLE_LOCALE_SUPPORT
static void FAST_FUNC
change_lc_all(const char *value)
{
if (value && *value != '\0')
setlocale(LC_ALL, value);
}
static void FAST_FUNC
change_lc_ctype(const char *value)
{
if (value && *value != '\0')
setlocale(LC_CTYPE, value);
}
#endif
#if ENABLE_ASH_MAIL
static void chkmail(void);
static void changemail(const char *) FAST_FUNC;
#endif
static void changepath(const char *) FAST_FUNC;
#if ENABLE_ASH_RANDOM_SUPPORT
static void change_random(const char *) FAST_FUNC;
#endif
static const struct {
int flags;
const char *text;
void (*func)(const char *) FAST_FUNC;
} varinit_data[] = {
{ VSTRFIXED|VTEXTFIXED , defifsvar , NULL },
#if ENABLE_ASH_MAIL
{ VSTRFIXED|VTEXTFIXED|VUNSET, "MAIL\0" , changemail },
{ VSTRFIXED|VTEXTFIXED|VUNSET, "MAILPATH\0", changemail },
#endif
{ VSTRFIXED|VTEXTFIXED , bb_PATH_root_path, changepath },
{ VSTRFIXED|VTEXTFIXED , "PS1=$ " , NULL },
{ VSTRFIXED|VTEXTFIXED , "PS2=> " , NULL },
{ VSTRFIXED|VTEXTFIXED , "PS4=+ " , NULL },
#if ENABLE_ASH_GETOPTS
{ VSTRFIXED|VTEXTFIXED , "OPTIND=1" , getoptsreset },
#endif
#if ENABLE_ASH_RANDOM_SUPPORT
{ VSTRFIXED|VTEXTFIXED|VUNSET|VDYNAMIC, "RANDOM\0", change_random },
#endif
#if ENABLE_LOCALE_SUPPORT
{ VSTRFIXED|VTEXTFIXED|VUNSET, "LC_ALL\0" , change_lc_all },
{ VSTRFIXED|VTEXTFIXED|VUNSET, "LC_CTYPE\0", change_lc_ctype },
#endif
#if ENABLE_FEATURE_EDITING_SAVEHISTORY
{ VSTRFIXED|VTEXTFIXED|VUNSET, "HISTFILE\0", NULL },
#endif
};
struct redirtab;
struct globals_var {
struct shparam shellparam; /* $@ current positional parameters */
struct redirtab *redirlist;
int g_nullredirs;
int preverrout_fd; /* save fd2 before print debug if xflag is set. */
struct var *vartab[VTABSIZE];
struct var varinit[ARRAY_SIZE(varinit_data)];
};
extern struct globals_var *const ash_ptr_to_globals_var;
#define G_var (*ash_ptr_to_globals_var)
#define shellparam (G_var.shellparam )
//#define redirlist (G_var.redirlist )
#define g_nullredirs (G_var.g_nullredirs )
#define preverrout_fd (G_var.preverrout_fd)
#define vartab (G_var.vartab )
#define varinit (G_var.varinit )
#define INIT_G_var() do { \
unsigned i; \
(*(struct globals_var**)&ash_ptr_to_globals_var) = xzalloc(sizeof(G_var)); \
barrier(); \
for (i = 0; i < ARRAY_SIZE(varinit_data); i++) { \
varinit[i].flags = varinit_data[i].flags; \
varinit[i].text = varinit_data[i].text; \
varinit[i].func = varinit_data[i].func; \
} \
} while (0)
#define vifs varinit[0]
#if ENABLE_ASH_MAIL
# define vmail (&vifs)[1]
# define vmpath (&vmail)[1]
# define vpath (&vmpath)[1]
#else
# define vpath (&vifs)[1]
#endif
#define vps1 (&vpath)[1]
#define vps2 (&vps1)[1]
#define vps4 (&vps2)[1]
#if ENABLE_ASH_GETOPTS
# define voptind (&vps4)[1]
# if ENABLE_ASH_RANDOM_SUPPORT
# define vrandom (&voptind)[1]
# endif
#else
# if ENABLE_ASH_RANDOM_SUPPORT
# define vrandom (&vps4)[1]
# endif
#endif
/*
* The following macros access the values of the above variables.
* They have to skip over the name. They return the null string
* for unset variables.
*/
#define ifsval() (vifs.text + 4)
#define ifsset() ((vifs.flags & VUNSET) == 0)
#if ENABLE_ASH_MAIL
# define mailval() (vmail.text + 5)
# define mpathval() (vmpath.text + 9)
# define mpathset() ((vmpath.flags & VUNSET) == 0)
#endif
#define pathval() (vpath.text + 5)
#define ps1val() (vps1.text + 4)
#define ps2val() (vps2.text + 4)
#define ps4val() (vps4.text + 4)
#if ENABLE_ASH_GETOPTS
# define optindval() (voptind.text + 7)
#endif
#define is_name(c) ((c) == '_' || isalpha((unsigned char)(c)))
#define is_in_name(c) ((c) == '_' || isalnum((unsigned char)(c)))
#if ENABLE_ASH_GETOPTS
static void FAST_FUNC
getoptsreset(const char *value)
{
shellparam.optind = number(value);
shellparam.optoff = -1;
}
#endif
/*
* Return of a legal variable name (a letter or underscore followed by zero or
* more letters, underscores, and digits).
*/
static char* FAST_FUNC
endofname(const char *name)
{
char *p;
p = (char *) name;
if (!is_name(*p))
return p;
while (*++p) {
if (!is_in_name(*p))
break;
}
return p;
}
/*
* Compares two strings up to the first = or '\0'. The first
* string must be terminated by '='; the second may be terminated by
* either '=' or '\0'.
*/
static int
varcmp(const char *p, const char *q)
{
int c, d;
while ((c = *p) == (d = *q)) {
if (!c || c == '=')
goto out;
p++;
q++;
}
if (c == '=')
c = '\0';
if (d == '=')
d = '\0';
out:
return c - d;
}
static int
varequal(const char *a, const char *b)
{
return !varcmp(a, b);
}
/*
* Find the appropriate entry in the hash table from the name.
*/
static struct var **
hashvar(const char *p)
{
unsigned hashval;
hashval = ((unsigned char) *p) << 4;
while (*p && *p != '=')
hashval += (unsigned char) *p++;
return &vartab[hashval % VTABSIZE];
}
static int
vpcmp(const void *a, const void *b)
{
return varcmp(*(const char **)a, *(const char **)b);
}
/*
* This routine initializes the builtin variables.
*/
static void
initvar(void)
{
struct var *vp;
struct var *end;
struct var **vpp;
/*
* PS1 depends on uid
*/
#if ENABLE_FEATURE_EDITING && ENABLE_FEATURE_EDITING_FANCY_PROMPT
vps1.text = "PS1=\\w \\$ ";
#else
if (!geteuid())
vps1.text = "PS1=# ";
#endif
vp = varinit;
end = vp + ARRAY_SIZE(varinit);
do {
vpp = hashvar(vp->text);
vp->next = *vpp;
*vpp = vp;
} while (++vp < end);
}
static struct var **
findvar(struct var **vpp, const char *name)
{
for (; *vpp; vpp = &(*vpp)->next) {
if (varequal((*vpp)->text, name)) {
break;
}
}
return vpp;
}
/*
* Find the value of a variable. Returns NULL if not set.
*/
static const char* FAST_FUNC
lookupvar(const char *name)
{
struct var *v;
v = *findvar(hashvar(name), name);
if (v) {
#if ENABLE_ASH_RANDOM_SUPPORT
/*
* Dynamic variables are implemented roughly the same way they are
* in bash. Namely, they're "special" so long as they aren't unset.
* As soon as they're unset, they're no longer dynamic, and dynamic
* lookup will no longer happen at that point. -- PFM.
*/
if ((v->flags & VDYNAMIC))
(*v->func)(NULL);
#endif
if (!(v->flags & VUNSET))
return strchrnul(v->text, '=') + 1;
}
return NULL;
}
/*
* Search the environment of a builtin command.
*/
static const char *
bltinlookup(const char *name)
{
struct strlist *sp;
for (sp = cmdenviron; sp; sp = sp->next) {
if (varequal(sp->text, name))
return strchrnul(sp->text, '=') + 1;
}
return lookupvar(name);
}
/*
* Same as setvar except that the variable and value are passed in
* the first argument as name=value. Since the first argument will
* be actually stored in the table, it should not be a string that
* will go away.
* Called with interrupts off.
*/
static void
setvareq(char *s, int flags)
{
struct var *vp, **vpp;
vpp = hashvar(s);
flags |= (VEXPORT & (((unsigned) (1 - aflag)) - 1));
vp = *findvar(vpp, s);
if (vp) {
if ((vp->flags & (VREADONLY|VDYNAMIC)) == VREADONLY) {
const char *n;
if (flags & VNOSAVE)
free(s);
n = vp->text;
ash_msg_and_raise_error("%.*s: is read only", strchrnul(n, '=') - n, n);
}
if (flags & VNOSET)
return;
if (vp->func && (flags & VNOFUNC) == 0)
(*vp->func)(strchrnul(s, '=') + 1);
if ((vp->flags & (VTEXTFIXED|VSTACK)) == 0)
free((char*)vp->text);
flags |= vp->flags & ~(VTEXTFIXED|VSTACK|VNOSAVE|VUNSET);
} else {
if (flags & VNOSET)
return;
/* not found */
vp = ckzalloc(sizeof(*vp));
vp->next = *vpp;
/*vp->func = NULL; - ckzalloc did it */
*vpp = vp;
}
if (!(flags & (VTEXTFIXED|VSTACK|VNOSAVE)))
s = ckstrdup(s);
vp->text = s;
vp->flags = flags;
}
/*
* Set the value of a variable. The flags argument is ored with the
* flags of the variable. If val is NULL, the variable is unset.
*/
static void
setvar(const char *name, const char *val, int flags)
{
char *p, *q;
size_t namelen;
char *nameeq;
size_t vallen;
q = endofname(name);
p = strchrnul(q, '=');
namelen = p - name;
if (!namelen || p != q)
ash_msg_and_raise_error("%.*s: bad variable name", namelen, name);
vallen = 0;
if (val == NULL) {
flags |= VUNSET;
} else {
vallen = strlen(val);
}
INT_OFF;
nameeq = ckmalloc(namelen + vallen + 2);
p = (char *)memcpy(nameeq, name, namelen) + namelen;
if (val) {
*p++ = '=';
p = (char *)memcpy(p, val, vallen) + vallen;
}
*p = '\0';
setvareq(nameeq, flags | VNOSAVE);
INT_ON;
}
static void FAST_FUNC
setvar2(const char *name, const char *val)
{
setvar(name, val, 0);
}
#if ENABLE_ASH_GETOPTS
/*
* Safe version of setvar, returns 1 on success 0 on failure.
*/
static int
setvarsafe(const char *name, const char *val, int flags)
{
int err;
volatile int saveint;
struct jmploc *volatile savehandler = exception_handler;
struct jmploc jmploc;
SAVE_INT(saveint);
if (setjmp(jmploc.loc))
err = 1;
else {
exception_handler = &jmploc;
setvar(name, val, flags);
err = 0;
}
exception_handler = savehandler;
RESTORE_INT(saveint);
return err;
}
#endif
/*
* Unset the specified variable.
*/
static int
unsetvar(const char *s)
{
struct var **vpp;
struct var *vp;
int retval;
vpp = findvar(hashvar(s), s);
vp = *vpp;
retval = 2;
if (vp) {
int flags = vp->flags;
retval = 1;
if (flags & VREADONLY)
goto out;
#if ENABLE_ASH_RANDOM_SUPPORT
vp->flags &= ~VDYNAMIC;
#endif
if (flags & VUNSET)
goto ok;
if ((flags & VSTRFIXED) == 0) {
INT_OFF;
if ((flags & (VTEXTFIXED|VSTACK)) == 0)
free((char*)vp->text);
*vpp = vp->next;
free(vp);
INT_ON;
} else {
setvar(s, 0, 0);
vp->flags &= ~VEXPORT;
}
ok:
retval = 0;
}
out:
return retval;
}
/*
* Process a linked list of variable assignments.
*/
static void
listsetvar(struct strlist *list_set_var, int flags)
{
struct strlist *lp = list_set_var;
if (!lp)
return;
INT_OFF;
do {
setvareq(lp->text, flags);
lp = lp->next;
} while (lp);
INT_ON;
}
/*
* Generate a list of variables satisfying the given conditions.
*/
static char **
listvars(int on, int off, char ***end)
{
struct var **vpp;
struct var *vp;
char **ep;
int mask;
STARTSTACKSTR(ep);
vpp = vartab;
mask = on | off;
do {
for (vp = *vpp; vp; vp = vp->next) {
if ((vp->flags & mask) == on) {
if (ep == stackstrend())
ep = growstackstr();
*ep++ = (char *) vp->text;
}
}
} while (++vpp < vartab + VTABSIZE);
if (ep == stackstrend())
ep = growstackstr();
if (end)
*end = ep;
*ep++ = NULL;
return grabstackstr(ep);
}
/* ============ Path search helper
*
* The variable path (passed by reference) should be set to the start
* of the path before the first call; path_advance will update
* this value as it proceeds. Successive calls to path_advance will return
* the possible path expansions in sequence. If an option (indicated by
* a percent sign) appears in the path entry then the global variable
* pathopt will be set to point to it; otherwise pathopt will be set to
* NULL.
*/
static const char *pathopt; /* set by path_advance */
static char *
path_advance(const char **path, const char *name)
{
const char *p;
char *q;
const char *start;
size_t len;
if (*path == NULL)
return NULL;
start = *path;
for (p = start; *p && *p != ':' && *p != '%'; p++)
continue;
len = p - start + strlen(name) + 2; /* "2" is for '/' and '\0' */
while (stackblocksize() < len)
growstackblock();
q = stackblock();
if (p != start) {
memcpy(q, start, p - start);
q += p - start;
*q++ = '/';
}
strcpy(q, name);
pathopt = NULL;
if (*p == '%') {
pathopt = ++p;
while (*p && *p != ':')
p++;
}
if (*p == ':')
*path = p + 1;
else
*path = NULL;
return stalloc(len);
}
/* ============ Prompt */
static smallint doprompt; /* if set, prompt the user */
static smallint needprompt; /* true if interactive and at start of line */
#if ENABLE_FEATURE_EDITING
static line_input_t *line_input_state;
static const char *cmdedit_prompt;
static void
putprompt(const char *s)
{
if (ENABLE_ASH_EXPAND_PRMT) {
free((char*)cmdedit_prompt);
cmdedit_prompt = ckstrdup(s);
return;
}
cmdedit_prompt = s;
}
#else
static void
putprompt(const char *s)
{
out2str(s);
}
#endif
#if ENABLE_ASH_EXPAND_PRMT
/* expandstr() needs parsing machinery, so it is far away ahead... */
static const char *expandstr(const char *ps);
#else
#define expandstr(s) s
#endif
static void
setprompt(int whichprompt)
{
const char *prompt;
#if ENABLE_ASH_EXPAND_PRMT
struct stackmark smark;
#endif
needprompt = 0;
switch (whichprompt) {
case 1:
prompt = ps1val();
break;
case 2:
prompt = ps2val();
break;
default: /* 0 */
prompt = nullstr;
}
#if ENABLE_ASH_EXPAND_PRMT
setstackmark(&smark);
stalloc(stackblocksize());
#endif
putprompt(expandstr(prompt));
#if ENABLE_ASH_EXPAND_PRMT
popstackmark(&smark);
#endif
}
/* ============ The cd and pwd commands */
#define CD_PHYSICAL 1
#define CD_PRINT 2
static int
cdopt(void)
{
int flags = 0;
int i, j;
j = 'L';
while ((i = nextopt("LP")) != '\0') {
if (i != j) {
flags ^= CD_PHYSICAL;
j = i;
}
}
return flags;
}
/*
* Update curdir (the name of the current directory) in response to a
* cd command.
*/
static const char *
updatepwd(const char *dir)
{
char *new;
char *p;
char *cdcomppath;
const char *lim;
cdcomppath = ststrdup(dir);
STARTSTACKSTR(new);
if (*dir != '/') {
if (curdir == nullstr)
return 0;
new = stack_putstr(curdir, new);
}
new = makestrspace(strlen(dir) + 2, new);
lim = (char *)stackblock() + 1;
if (*dir != '/') {
if (new[-1] != '/')
USTPUTC('/', new);
if (new > lim && *lim == '/')
lim++;
} else {
USTPUTC('/', new);
cdcomppath++;
if (dir[1] == '/' && dir[2] != '/') {
USTPUTC('/', new);
cdcomppath++;
lim++;
}
}
p = strtok(cdcomppath, "/");
while (p) {
switch (*p) {
case '.':
if (p[1] == '.' && p[2] == '\0') {
while (new > lim) {
STUNPUTC(new);
if (new[-1] == '/')
break;
}
break;
}
if (p[1] == '\0')
break;
/* fall through */
default:
new = stack_putstr(p, new);
USTPUTC('/', new);
}
p = strtok(0, "/");
}
if (new > lim)
STUNPUTC(new);
*new = 0;
return stackblock();
}
/*
* Find out what the current directory is. If we already know the current
* directory, this routine returns immediately.
*/
static char *
getpwd(void)
{
char *dir = getcwd(NULL, 0); /* huh, using glibc extension? */
return dir ? dir : nullstr;
}
static void
setpwd(const char *val, int setold)
{
char *oldcur, *dir;
oldcur = dir = curdir;
if (setold) {
setvar("OLDPWD", oldcur, VEXPORT);
}
INT_OFF;
if (physdir != nullstr) {
if (physdir != oldcur)
free(physdir);
physdir = nullstr;
}
if (oldcur == val || !val) {
char *s = getpwd();
physdir = s;
if (!val)
dir = s;
} else
dir = ckstrdup(val);
if (oldcur != dir && oldcur != nullstr) {
free(oldcur);
}
curdir = dir;
INT_ON;
setvar("PWD", dir, VEXPORT);
}
static void hashcd(void);
/*
* Actually do the chdir. We also call hashcd to let the routines in exec.c
* know that the current directory has changed.
*/
static int
docd(const char *dest, int flags)
{
const char *dir = NULL;
int err;
TRACE(("docd(\"%s\", %d) called\n", dest, flags));
INT_OFF;
if (!(flags & CD_PHYSICAL)) {
dir = updatepwd(dest);
if (dir)
dest = dir;
}
err = chdir(dest);
if (err)
goto out;
setpwd(dir, 1);
hashcd();
out:
INT_ON;
return err;
}
static int FAST_FUNC
cdcmd(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
{
const char *dest;
const char *path;
const char *p;
char c;
struct stat statb;
int flags;
flags = cdopt();
dest = *argptr;
if (!dest)
dest = bltinlookup(homestr);
else if (LONE_DASH(dest)) {
dest = bltinlookup("OLDPWD");
flags |= CD_PRINT;
}
if (!dest)
dest = nullstr;
if (*dest == '/')
goto step7;
if (*dest == '.') {
c = dest[1];
dotdot:
switch (c) {
case '\0':
case '/':
goto step6;
case '.':
c = dest[2];
if (c != '.')
goto dotdot;
}
}
if (!*dest)
dest = ".";
path = bltinlookup("CDPATH");
if (!path) {
step6:
step7:
p = dest;
goto docd;
}
do {
c = *path;
p = path_advance(&path, dest);
if (stat(p, &statb) >= 0 && S_ISDIR(statb.st_mode)) {
if (c && c != ':')
flags |= CD_PRINT;
docd:
if (!docd(p, flags))
goto out;
break;
}
} while (path);
ash_msg_and_raise_error("can't cd to %s", dest);
/* NOTREACHED */
out:
if (flags & CD_PRINT)
out1fmt(snlfmt, curdir);
return 0;
}
static int FAST_FUNC
pwdcmd(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
{
int flags;
const char *dir = curdir;
flags = cdopt();
if (flags) {
if (physdir == nullstr)
setpwd(dir, 0);
dir = physdir;
}
out1fmt(snlfmt, dir);
return 0;
}
/* ============ ... */
#define IBUFSIZ (ENABLE_FEATURE_EDITING ? CONFIG_FEATURE_EDITING_MAX_LEN : 1024)
/* Syntax classes */
#define CWORD 0 /* character is nothing special */
#define CNL 1 /* newline character */
#define CBACK 2 /* a backslash character */
#define CSQUOTE 3 /* single quote */
#define CDQUOTE 4 /* double quote */
#define CENDQUOTE 5 /* a terminating quote */
#define CBQUOTE 6 /* backwards single quote */
#define CVAR 7 /* a dollar sign */
#define CENDVAR 8 /* a '}' character */
#define CLP 9 /* a left paren in arithmetic */
#define CRP 10 /* a right paren in arithmetic */
#define CENDFILE 11 /* end of file */
#define CCTL 12 /* like CWORD, except it must be escaped */
#define CSPCL 13 /* these terminate a word */
#define CIGN 14 /* character should be ignored */
#define PEOF 256
#if ENABLE_ASH_ALIAS
# define PEOA 257
#endif
#define USE_SIT_FUNCTION ENABLE_ASH_OPTIMIZE_FOR_SIZE
#if ENABLE_SH_MATH_SUPPORT
# define SIT_ITEM(a,b,c,d) (a | (b << 4) | (c << 8) | (d << 12))
#else
# define SIT_ITEM(a,b,c,d) (a | (b << 4) | (c << 8))
#endif
static const uint16_t S_I_T[] = {
#if ENABLE_ASH_ALIAS
SIT_ITEM(CSPCL , CIGN , CIGN , CIGN ), /* 0, PEOA */
#endif
SIT_ITEM(CSPCL , CWORD , CWORD, CWORD ), /* 1, ' ' */
SIT_ITEM(CNL , CNL , CNL , CNL ), /* 2, \n */
SIT_ITEM(CWORD , CCTL , CCTL , CWORD ), /* 3, !*-/:=?[]~ */
SIT_ITEM(CDQUOTE , CENDQUOTE, CWORD, CWORD ), /* 4, '"' */
SIT_ITEM(CVAR , CVAR , CWORD, CVAR ), /* 5, $ */
SIT_ITEM(CSQUOTE , CWORD , CENDQUOTE, CWORD), /* 6, "'" */
SIT_ITEM(CSPCL , CWORD , CWORD, CLP ), /* 7, ( */
SIT_ITEM(CSPCL , CWORD , CWORD, CRP ), /* 8, ) */
SIT_ITEM(CBACK , CBACK , CCTL , CBACK ), /* 9, \ */
SIT_ITEM(CBQUOTE , CBQUOTE , CWORD, CBQUOTE), /* 10, ` */
SIT_ITEM(CENDVAR , CENDVAR , CWORD, CENDVAR), /* 11, } */
#if !USE_SIT_FUNCTION
SIT_ITEM(CENDFILE, CENDFILE , CENDFILE, CENDFILE),/* 12, PEOF */
SIT_ITEM(CWORD , CWORD , CWORD, CWORD ), /* 13, 0-9A-Za-z */
SIT_ITEM(CCTL , CCTL , CCTL , CCTL ) /* 14, CTLESC ... */
#endif
#undef SIT_ITEM
};
/* Constants below must match table above */
enum {
#if ENABLE_ASH_ALIAS
CSPCL_CIGN_CIGN_CIGN , /* 0 */
#endif
CSPCL_CWORD_CWORD_CWORD , /* 1 */
CNL_CNL_CNL_CNL , /* 2 */
CWORD_CCTL_CCTL_CWORD , /* 3 */
CDQUOTE_CENDQUOTE_CWORD_CWORD , /* 4 */
CVAR_CVAR_CWORD_CVAR , /* 5 */
CSQUOTE_CWORD_CENDQUOTE_CWORD , /* 6 */
CSPCL_CWORD_CWORD_CLP , /* 7 */
CSPCL_CWORD_CWORD_CRP , /* 8 */
CBACK_CBACK_CCTL_CBACK , /* 9 */
CBQUOTE_CBQUOTE_CWORD_CBQUOTE , /* 10 */
CENDVAR_CENDVAR_CWORD_CENDVAR , /* 11 */
CENDFILE_CENDFILE_CENDFILE_CENDFILE, /* 12 */
CWORD_CWORD_CWORD_CWORD , /* 13 */
CCTL_CCTL_CCTL_CCTL , /* 14 */
};
/* c in SIT(c, syntax) must be an *unsigned char* or PEOA or PEOF,
* caller must ensure proper cast on it if c is *char_ptr!
*/
/* Values for syntax param */
#define BASESYNTAX 0 /* not in quotes */
#define DQSYNTAX 1 /* in double quotes */
#define SQSYNTAX 2 /* in single quotes */
#define ARISYNTAX 3 /* in arithmetic */
#define PSSYNTAX 4 /* prompt. never passed to SIT() */
#if USE_SIT_FUNCTION
static int
SIT(int c, int syntax)
{
static const char spec_symbls[] ALIGN1 = "\t\n !\"$&'()*-/:;<=>?[\\]`|}~";
# if ENABLE_ASH_ALIAS
static const uint8_t syntax_index_table[] ALIGN1 = {
1, 2, 1, 3, 4, 5, 1, 6, /* "\t\n !\"$&'" */
7, 8, 3, 3, 3, 3, 1, 1, /* "()*-/:;<" */
3, 1, 3, 3, 9, 3, 10, 1, /* "=>?[\\]`|" */
11, 3 /* "}~" */
};
# else
static const uint8_t syntax_index_table[] ALIGN1 = {
0, 1, 0, 2, 3, 4, 0, 5, /* "\t\n !\"$&'" */
6, 7, 2, 2, 2, 2, 0, 0, /* "()*-/:;<" */
2, 0, 2, 2, 8, 2, 9, 0, /* "=>?[\\]`|" */
10, 2 /* "}~" */
};
# endif
const char *s;
int indx;
if (c == PEOF)
return CENDFILE;
# if ENABLE_ASH_ALIAS
if (c == PEOA)
indx = 0;
else
# endif
{
/* Cast is purely for paranoia here,
* just in case someone passed signed char to us */
if ((unsigned char)c >= CTL_FIRST
&& (unsigned char)c <= CTL_LAST
) {
return CCTL;
}
s = strchrnul(spec_symbls, c);
if (*s == '\0')
return CWORD;
indx = syntax_index_table[s - spec_symbls];
}
return (S_I_T[indx] >> (syntax*4)) & 0xf;
}
#else /* !USE_SIT_FUNCTION */
static const uint8_t syntax_index_table[] = {
/* BASESYNTAX_DQSYNTAX_SQSYNTAX_ARISYNTAX */
/* 0 */ CWORD_CWORD_CWORD_CWORD,
/* 1 */ CWORD_CWORD_CWORD_CWORD,
/* 2 */ CWORD_CWORD_CWORD_CWORD,
/* 3 */ CWORD_CWORD_CWORD_CWORD,
/* 4 */ CWORD_CWORD_CWORD_CWORD,
/* 5 */ CWORD_CWORD_CWORD_CWORD,
/* 6 */ CWORD_CWORD_CWORD_CWORD,
/* 7 */ CWORD_CWORD_CWORD_CWORD,
/* 8 */ CWORD_CWORD_CWORD_CWORD,
/* 9 "\t" */ CSPCL_CWORD_CWORD_CWORD,
/* 10 "\n" */ CNL_CNL_CNL_CNL,
/* 11 */ CWORD_CWORD_CWORD_CWORD,
/* 12 */ CWORD_CWORD_CWORD_CWORD,
/* 13 */ CWORD_CWORD_CWORD_CWORD,
/* 14 */ CWORD_CWORD_CWORD_CWORD,
/* 15 */ CWORD_CWORD_CWORD_CWORD,
/* 16 */ CWORD_CWORD_CWORD_CWORD,
/* 17 */ CWORD_CWORD_CWORD_CWORD,
/* 18 */ CWORD_CWORD_CWORD_CWORD,
/* 19 */ CWORD_CWORD_CWORD_CWORD,
/* 20 */ CWORD_CWORD_CWORD_CWORD,
/* 21 */ CWORD_CWORD_CWORD_CWORD,
/* 22 */ CWORD_CWORD_CWORD_CWORD,
/* 23 */ CWORD_CWORD_CWORD_CWORD,
/* 24 */ CWORD_CWORD_CWORD_CWORD,
/* 25 */ CWORD_CWORD_CWORD_CWORD,
/* 26 */ CWORD_CWORD_CWORD_CWORD,
/* 27 */ CWORD_CWORD_CWORD_CWORD,
/* 28 */ CWORD_CWORD_CWORD_CWORD,
/* 29 */ CWORD_CWORD_CWORD_CWORD,
/* 30 */ CWORD_CWORD_CWORD_CWORD,
/* 31 */ CWORD_CWORD_CWORD_CWORD,
/* 32 " " */ CSPCL_CWORD_CWORD_CWORD,
/* 33 "!" */ CWORD_CCTL_CCTL_CWORD,
/* 34 """ */ CDQUOTE_CENDQUOTE_CWORD_CWORD,
/* 35 "#" */ CWORD_CWORD_CWORD_CWORD,
/* 36 "$" */ CVAR_CVAR_CWORD_CVAR,
/* 37 "%" */ CWORD_CWORD_CWORD_CWORD,
/* 38 "&" */ CSPCL_CWORD_CWORD_CWORD,
/* 39 "'" */ CSQUOTE_CWORD_CENDQUOTE_CWORD,
/* 40 "(" */ CSPCL_CWORD_CWORD_CLP,
/* 41 ")" */ CSPCL_CWORD_CWORD_CRP,
/* 42 "*" */ CWORD_CCTL_CCTL_CWORD,
/* 43 "+" */ CWORD_CWORD_CWORD_CWORD,
/* 44 "," */ CWORD_CWORD_CWORD_CWORD,
/* 45 "-" */ CWORD_CCTL_CCTL_CWORD,
/* 46 "." */ CWORD_CWORD_CWORD_CWORD,
/* 47 "/" */ CWORD_CCTL_CCTL_CWORD,
/* 48 "0" */ CWORD_CWORD_CWORD_CWORD,
/* 49 "1" */ CWORD_CWORD_CWORD_CWORD,
/* 50 "2" */ CWORD_CWORD_CWORD_CWORD,
/* 51 "3" */ CWORD_CWORD_CWORD_CWORD,
/* 52 "4" */ CWORD_CWORD_CWORD_CWORD,
/* 53 "5" */ CWORD_CWORD_CWORD_CWORD,
/* 54 "6" */ CWORD_CWORD_CWORD_CWORD,
/* 55 "7" */ CWORD_CWORD_CWORD_CWORD,
/* 56 "8" */ CWORD_CWORD_CWORD_CWORD,
/* 57 "9" */ CWORD_CWORD_CWORD_CWORD,
/* 58 ":" */ CWORD_CCTL_CCTL_CWORD,
/* 59 ";" */ CSPCL_CWORD_CWORD_CWORD,
/* 60 "<" */ CSPCL_CWORD_CWORD_CWORD,
/* 61 "=" */ CWORD_CCTL_CCTL_CWORD,
/* 62 ">" */ CSPCL_CWORD_CWORD_CWORD,
/* 63 "?" */ CWORD_CCTL_CCTL_CWORD,
/* 64 "@" */ CWORD_CWORD_CWORD_CWORD,
/* 65 "A" */ CWORD_CWORD_CWORD_CWORD,
/* 66 "B" */ CWORD_CWORD_CWORD_CWORD,
/* 67 "C" */ CWORD_CWORD_CWORD_CWORD,
/* 68 "D" */ CWORD_CWORD_CWORD_CWORD,
/* 69 "E" */ CWORD_CWORD_CWORD_CWORD,
/* 70 "F" */ CWORD_CWORD_CWORD_CWORD,
/* 71 "G" */ CWORD_CWORD_CWORD_CWORD,
/* 72 "H" */ CWORD_CWORD_CWORD_CWORD,
/* 73 "I" */ CWORD_CWORD_CWORD_CWORD,
/* 74 "J" */ CWORD_CWORD_CWORD_CWORD,
/* 75 "K" */ CWORD_CWORD_CWORD_CWORD,
/* 76 "L" */ CWORD_CWORD_CWORD_CWORD,
/* 77 "M" */ CWORD_CWORD_CWORD_CWORD,
/* 78 "N" */ CWORD_CWORD_CWORD_CWORD,
/* 79 "O" */ CWORD_CWORD_CWORD_CWORD,
/* 80 "P" */ CWORD_CWORD_CWORD_CWORD,
/* 81 "Q" */ CWORD_CWORD_CWORD_CWORD,
/* 82 "R" */ CWORD_CWORD_CWORD_CWORD,
/* 83 "S" */ CWORD_CWORD_CWORD_CWORD,
/* 84 "T" */ CWORD_CWORD_CWORD_CWORD,
/* 85 "U" */ CWORD_CWORD_CWORD_CWORD,
/* 86 "V" */ CWORD_CWORD_CWORD_CWORD,
/* 87 "W" */ CWORD_CWORD_CWORD_CWORD,
/* 88 "X" */ CWORD_CWORD_CWORD_CWORD,
/* 89 "Y" */ CWORD_CWORD_CWORD_CWORD,
/* 90 "Z" */ CWORD_CWORD_CWORD_CWORD,
/* 91 "[" */ CWORD_CCTL_CCTL_CWORD,
/* 92 "\" */ CBACK_CBACK_CCTL_CBACK,
/* 93 "]" */ CWORD_CCTL_CCTL_CWORD,
/* 94 "^" */ CWORD_CWORD_CWORD_CWORD,
/* 95 "_" */ CWORD_CWORD_CWORD_CWORD,
/* 96 "`" */ CBQUOTE_CBQUOTE_CWORD_CBQUOTE,
/* 97 "a" */ CWORD_CWORD_CWORD_CWORD,
/* 98 "b" */ CWORD_CWORD_CWORD_CWORD,
/* 99 "c" */ CWORD_CWORD_CWORD_CWORD,
/* 100 "d" */ CWORD_CWORD_CWORD_CWORD,
/* 101 "e" */ CWORD_CWORD_CWORD_CWORD,
/* 102 "f" */ CWORD_CWORD_CWORD_CWORD,
/* 103 "g" */ CWORD_CWORD_CWORD_CWORD,
/* 104 "h" */ CWORD_CWORD_CWORD_CWORD,
/* 105 "i" */ CWORD_CWORD_CWORD_CWORD,
/* 106 "j" */ CWORD_CWORD_CWORD_CWORD,
/* 107 "k" */ CWORD_CWORD_CWORD_CWORD,
/* 108 "l" */ CWORD_CWORD_CWORD_CWORD,
/* 109 "m" */ CWORD_CWORD_CWORD_CWORD,
/* 110 "n" */ CWORD_CWORD_CWORD_CWORD,
/* 111 "o" */ CWORD_CWORD_CWORD_CWORD,
/* 112 "p" */ CWORD_CWORD_CWORD_CWORD,
/* 113 "q" */ CWORD_CWORD_CWORD_CWORD,
/* 114 "r" */ CWORD_CWORD_CWORD_CWORD,
/* 115 "s" */ CWORD_CWORD_CWORD_CWORD,
/* 116 "t" */ CWORD_CWORD_CWORD_CWORD,
/* 117 "u" */ CWORD_CWORD_CWORD_CWORD,
/* 118 "v" */ CWORD_CWORD_CWORD_CWORD,
/* 119 "w" */ CWORD_CWORD_CWORD_CWORD,
/* 120 "x" */ CWORD_CWORD_CWORD_CWORD,
/* 121 "y" */ CWORD_CWORD_CWORD_CWORD,
/* 122 "z" */ CWORD_CWORD_CWORD_CWORD,
/* 123 "{" */ CWORD_CWORD_CWORD_CWORD,
/* 124 "|" */ CSPCL_CWORD_CWORD_CWORD,
/* 125 "}" */ CENDVAR_CENDVAR_CWORD_CENDVAR,
/* 126 "~" */ CWORD_CCTL_CCTL_CWORD,
/* 127 del */ CWORD_CWORD_CWORD_CWORD,
/* 128 0x80 */ CWORD_CWORD_CWORD_CWORD,
/* 129 CTLESC */ CCTL_CCTL_CCTL_CCTL,
/* 130 CTLVAR */ CCTL_CCTL_CCTL_CCTL,
/* 131 CTLENDVAR */ CCTL_CCTL_CCTL_CCTL,
/* 132 CTLBACKQ */ CCTL_CCTL_CCTL_CCTL,
/* 133 CTLQUOTE */ CCTL_CCTL_CCTL_CCTL,
/* 134 CTLARI */ CCTL_CCTL_CCTL_CCTL,
/* 135 CTLENDARI */ CCTL_CCTL_CCTL_CCTL,
/* 136 CTLQUOTEMARK */ CCTL_CCTL_CCTL_CCTL,
/* 137 */ CWORD_CWORD_CWORD_CWORD,
/* 138 */ CWORD_CWORD_CWORD_CWORD,
/* 139 */ CWORD_CWORD_CWORD_CWORD,
/* 140 */ CWORD_CWORD_CWORD_CWORD,
/* 141 */ CWORD_CWORD_CWORD_CWORD,
/* 142 */ CWORD_CWORD_CWORD_CWORD,
/* 143 */ CWORD_CWORD_CWORD_CWORD,
/* 144 */ CWORD_CWORD_CWORD_CWORD,
/* 145 */ CWORD_CWORD_CWORD_CWORD,
/* 146 */ CWORD_CWORD_CWORD_CWORD,
/* 147 */ CWORD_CWORD_CWORD_CWORD,
/* 148 */ CWORD_CWORD_CWORD_CWORD,
/* 149 */ CWORD_CWORD_CWORD_CWORD,
/* 150 */ CWORD_CWORD_CWORD_CWORD,
/* 151 */ CWORD_CWORD_CWORD_CWORD,
/* 152 */ CWORD_CWORD_CWORD_CWORD,
/* 153 */ CWORD_CWORD_CWORD_CWORD,
/* 154 */ CWORD_CWORD_CWORD_CWORD,
/* 155 */ CWORD_CWORD_CWORD_CWORD,
/* 156 */ CWORD_CWORD_CWORD_CWORD,
/* 157 */ CWORD_CWORD_CWORD_CWORD,
/* 158 */ CWORD_CWORD_CWORD_CWORD,
/* 159 */ CWORD_CWORD_CWORD_CWORD,
/* 160 */ CWORD_CWORD_CWORD_CWORD,
/* 161 */ CWORD_CWORD_CWORD_CWORD,
/* 162 */ CWORD_CWORD_CWORD_CWORD,
/* 163 */ CWORD_CWORD_CWORD_CWORD,
/* 164 */ CWORD_CWORD_CWORD_CWORD,
/* 165 */ CWORD_CWORD_CWORD_CWORD,
/* 166 */ CWORD_CWORD_CWORD_CWORD,
/* 167 */ CWORD_CWORD_CWORD_CWORD,
/* 168 */ CWORD_CWORD_CWORD_CWORD,
/* 169 */ CWORD_CWORD_CWORD_CWORD,
/* 170 */ CWORD_CWORD_CWORD_CWORD,
/* 171 */ CWORD_CWORD_CWORD_CWORD,
/* 172 */ CWORD_CWORD_CWORD_CWORD,
/* 173 */ CWORD_CWORD_CWORD_CWORD,
/* 174 */ CWORD_CWORD_CWORD_CWORD,
/* 175 */ CWORD_CWORD_CWORD_CWORD,
/* 176 */ CWORD_CWORD_CWORD_CWORD,
/* 177 */ CWORD_CWORD_CWORD_CWORD,
/* 178 */ CWORD_CWORD_CWORD_CWORD,
/* 179 */ CWORD_CWORD_CWORD_CWORD,
/* 180 */ CWORD_CWORD_CWORD_CWORD,
/* 181 */ CWORD_CWORD_CWORD_CWORD,
/* 182 */ CWORD_CWORD_CWORD_CWORD,
/* 183 */ CWORD_CWORD_CWORD_CWORD,
/* 184 */ CWORD_CWORD_CWORD_CWORD,
/* 185 */ CWORD_CWORD_CWORD_CWORD,
/* 186 */ CWORD_CWORD_CWORD_CWORD,
/* 187 */ CWORD_CWORD_CWORD_CWORD,
/* 188 */ CWORD_CWORD_CWORD_CWORD,
/* 189 */ CWORD_CWORD_CWORD_CWORD,
/* 190 */ CWORD_CWORD_CWORD_CWORD,
/* 191 */ CWORD_CWORD_CWORD_CWORD,
/* 192 */ CWORD_CWORD_CWORD_CWORD,
/* 193 */ CWORD_CWORD_CWORD_CWORD,
/* 194 */ CWORD_CWORD_CWORD_CWORD,
/* 195 */ CWORD_CWORD_CWORD_CWORD,
/* 196 */ CWORD_CWORD_CWORD_CWORD,
/* 197 */ CWORD_CWORD_CWORD_CWORD,
/* 198 */ CWORD_CWORD_CWORD_CWORD,
/* 199 */ CWORD_CWORD_CWORD_CWORD,
/* 200 */ CWORD_CWORD_CWORD_CWORD,
/* 201 */ CWORD_CWORD_CWORD_CWORD,
/* 202 */ CWORD_CWORD_CWORD_CWORD,
/* 203 */ CWORD_CWORD_CWORD_CWORD,
/* 204 */ CWORD_CWORD_CWORD_CWORD,
/* 205 */ CWORD_CWORD_CWORD_CWORD,
/* 206 */ CWORD_CWORD_CWORD_CWORD,
/* 207 */ CWORD_CWORD_CWORD_CWORD,
/* 208 */ CWORD_CWORD_CWORD_CWORD,
/* 209 */ CWORD_CWORD_CWORD_CWORD,
/* 210 */ CWORD_CWORD_CWORD_CWORD,
/* 211 */ CWORD_CWORD_CWORD_CWORD,
/* 212 */ CWORD_CWORD_CWORD_CWORD,
/* 213 */ CWORD_CWORD_CWORD_CWORD,
/* 214 */ CWORD_CWORD_CWORD_CWORD,
/* 215 */ CWORD_CWORD_CWORD_CWORD,
/* 216 */ CWORD_CWORD_CWORD_CWORD,
/* 217 */ CWORD_CWORD_CWORD_CWORD,
/* 218 */ CWORD_CWORD_CWORD_CWORD,
/* 219 */ CWORD_CWORD_CWORD_CWORD,
/* 220 */ CWORD_CWORD_CWORD_CWORD,
/* 221 */ CWORD_CWORD_CWORD_CWORD,
/* 222 */ CWORD_CWORD_CWORD_CWORD,
/* 223 */ CWORD_CWORD_CWORD_CWORD,
/* 224 */ CWORD_CWORD_CWORD_CWORD,
/* 225 */ CWORD_CWORD_CWORD_CWORD,
/* 226 */ CWORD_CWORD_CWORD_CWORD,
/* 227 */ CWORD_CWORD_CWORD_CWORD,
/* 228 */ CWORD_CWORD_CWORD_CWORD,
/* 229 */ CWORD_CWORD_CWORD_CWORD,
/* 230 */ CWORD_CWORD_CWORD_CWORD,
/* 231 */ CWORD_CWORD_CWORD_CWORD,
/* 232 */ CWORD_CWORD_CWORD_CWORD,
/* 233 */ CWORD_CWORD_CWORD_CWORD,
/* 234 */ CWORD_CWORD_CWORD_CWORD,
/* 235 */ CWORD_CWORD_CWORD_CWORD,
/* 236 */ CWORD_CWORD_CWORD_CWORD,
/* 237 */ CWORD_CWORD_CWORD_CWORD,
/* 238 */ CWORD_CWORD_CWORD_CWORD,
/* 239 */ CWORD_CWORD_CWORD_CWORD,
/* 230 */ CWORD_CWORD_CWORD_CWORD,
/* 241 */ CWORD_CWORD_CWORD_CWORD,
/* 242 */ CWORD_CWORD_CWORD_CWORD,
/* 243 */ CWORD_CWORD_CWORD_CWORD,
/* 244 */ CWORD_CWORD_CWORD_CWORD,
/* 245 */ CWORD_CWORD_CWORD_CWORD,
/* 246 */ CWORD_CWORD_CWORD_CWORD,
/* 247 */ CWORD_CWORD_CWORD_CWORD,
/* 248 */ CWORD_CWORD_CWORD_CWORD,
/* 249 */ CWORD_CWORD_CWORD_CWORD,
/* 250 */ CWORD_CWORD_CWORD_CWORD,
/* 251 */ CWORD_CWORD_CWORD_CWORD,
/* 252 */ CWORD_CWORD_CWORD_CWORD,
/* 253 */ CWORD_CWORD_CWORD_CWORD,
/* 254 */ CWORD_CWORD_CWORD_CWORD,
/* 255 */ CWORD_CWORD_CWORD_CWORD,
/* PEOF */ CENDFILE_CENDFILE_CENDFILE_CENDFILE,
# if ENABLE_ASH_ALIAS
/* PEOA */ CSPCL_CIGN_CIGN_CIGN,
# endif
};
# define SIT(c, syntax) ((S_I_T[syntax_index_table[c]] >> ((syntax)*4)) & 0xf)
#endif /* !USE_SIT_FUNCTION */
/* ============ Alias handling */
#if ENABLE_ASH_ALIAS
#define ALIASINUSE 1
#define ALIASDEAD 2
struct alias {
struct alias *next;
char *name;
char *val;
int flag;
};
static struct alias **atab; // [ATABSIZE];
#define INIT_G_alias() do { \
atab = xzalloc(ATABSIZE * sizeof(atab[0])); \
} while (0)
static struct alias **
__lookupalias(const char *name) {
unsigned int hashval;
struct alias **app;
const char *p;
unsigned int ch;
p = name;
ch = (unsigned char)*p;
hashval = ch << 4;
while (ch) {
hashval += ch;
ch = (unsigned char)*++p;
}
app = &atab[hashval % ATABSIZE];
for (; *app; app = &(*app)->next) {
if (strcmp(name, (*app)->name) == 0) {
break;
}
}
return app;
}
static struct alias *
lookupalias(const char *name, int check)
{
struct alias *ap = *__lookupalias(name);
if (check && ap && (ap->flag & ALIASINUSE))
return NULL;
return ap;
}
static struct alias *
freealias(struct alias *ap)
{
struct alias *next;
if (ap->flag & ALIASINUSE) {
ap->flag |= ALIASDEAD;
return ap;
}
next = ap->next;
free(ap->name);
free(ap->val);
free(ap);
return next;
}
static void
setalias(const char *name, const char *val)
{
struct alias *ap, **app;
app = __lookupalias(name);
ap = *app;
INT_OFF;
if (ap) {
if (!(ap->flag & ALIASINUSE)) {
free(ap->val);
}
ap->val = ckstrdup(val);
ap->flag &= ~ALIASDEAD;
} else {
/* not found */
ap = ckzalloc(sizeof(struct alias));
ap->name = ckstrdup(name);
ap->val = ckstrdup(val);
/*ap->flag = 0; - ckzalloc did it */
/*ap->next = NULL;*/
*app = ap;
}
INT_ON;
}
static int
unalias(const char *name)
{
struct alias **app;
app = __lookupalias(name);
if (*app) {
INT_OFF;
*app = freealias(*app);
INT_ON;
return 0;
}
return 1;
}
static void
rmaliases(void)
{
struct alias *ap, **app;
int i;
INT_OFF;
for (i = 0; i < ATABSIZE; i++) {
app = &atab[i];
for (ap = *app; ap; ap = *app) {
*app = freealias(*app);
if (ap == *app) {
app = &ap->next;
}
}
}
INT_ON;
}
static void
printalias(const struct alias *ap)
{
out1fmt("%s=%s\n", ap->name, single_quote(ap->val));
}
/*
* TODO - sort output
*/
static int FAST_FUNC
aliascmd(int argc UNUSED_PARAM, char **argv)
{
char *n, *v;
int ret = 0;
struct alias *ap;
if (!argv[1]) {
int i;
for (i = 0; i < ATABSIZE; i++) {
for (ap = atab[i]; ap; ap = ap->next) {
printalias(ap);
}
}
return 0;
}
while ((n = *++argv) != NULL) {
v = strchr(n+1, '=');
if (v == NULL) { /* n+1: funny ksh stuff */
ap = *__lookupalias(n);
if (ap == NULL) {
fprintf(stderr, "%s: %s not found\n", "alias", n);
ret = 1;
} else
printalias(ap);
} else {
*v++ = '\0';
setalias(n, v);
}
}
return ret;
}
static int FAST_FUNC
unaliascmd(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
{
int i;
while ((i = nextopt("a")) != '\0') {
if (i == 'a') {
rmaliases();
return 0;
}
}
for (i = 0; *argptr; argptr++) {
if (unalias(*argptr)) {
fprintf(stderr, "%s: %s not found\n", "unalias", *argptr);
i = 1;
}
}
return i;
}
#endif /* ASH_ALIAS */
/* ============ jobs.c */
/* Mode argument to forkshell. Don't change FORK_FG or FORK_BG. */
#define FORK_FG 0
#define FORK_BG 1
#define FORK_NOJOB 2
/* mode flags for showjob(s) */
#define SHOW_ONLY_PGID 0x01 /* show only pgid (jobs -p) */
#define SHOW_PIDS 0x02 /* show individual pids, not just one line per job */
#define SHOW_CHANGED 0x04 /* only jobs whose state has changed */
/*
* A job structure contains information about a job. A job is either a
* single process or a set of processes contained in a pipeline. In the
* latter case, pidlist will be non-NULL, and will point to a -1 terminated
* array of pids.
*/
struct procstat {
pid_t ps_pid; /* process id */
int ps_status; /* last process status from wait() */
char *ps_cmd; /* text of command being run */
};
struct job {
struct procstat ps0; /* status of process */
struct procstat *ps; /* status or processes when more than one */
#if JOBS
int stopstatus; /* status of a stopped job */
#endif
uint32_t
nprocs: 16, /* number of processes */
state: 8,
#define JOBRUNNING 0 /* at least one proc running */
#define JOBSTOPPED 1 /* all procs are stopped */
#define JOBDONE 2 /* all procs are completed */
#if JOBS
sigint: 1, /* job was killed by SIGINT */
jobctl: 1, /* job running under job control */
#endif
waited: 1, /* true if this entry has been waited for */
used: 1, /* true if this entry is in used */
changed: 1; /* true if status has changed */
struct job *prev_job; /* previous job */
};
static struct job *makejob(/*union node *,*/ int);
static int forkshell(struct job *, union node *, int);
static int waitforjob(struct job *);
#if !JOBS
enum { doing_jobctl = 0 };
#define setjobctl(on) do {} while (0)
#else
static smallint doing_jobctl; //references:8
static void setjobctl(int);
#endif
/*
* Ignore a signal.
*/
static void
ignoresig(int signo)
{
/* Avoid unnecessary system calls. Is it already SIG_IGNed? */
if (sigmode[signo - 1] != S_IGN && sigmode[signo - 1] != S_HARD_IGN) {
/* No, need to do it */
signal(signo, SIG_IGN);
}
sigmode[signo - 1] = S_HARD_IGN;
}
/*
* Only one usage site - in setsignal()
*/
static void
signal_handler(int signo)
{
gotsig[signo - 1] = 1;
if (signo == SIGINT && !trap[SIGINT]) {
if (!suppress_int) {
pending_sig = 0;
raise_interrupt(); /* does not return */
}
pending_int = 1;
} else {
pending_sig = signo;
}
}
/*
* Set the signal handler for the specified signal. The routine figures
* out what it should be set to.
*/
static void
setsignal(int signo)
{
char *t;
char cur_act, new_act;
struct sigaction act;
t = trap[signo];
new_act = S_DFL;
if (t != NULL) { /* trap for this sig is set */
new_act = S_CATCH;
if (t[0] == '\0') /* trap is "": ignore this sig */
new_act = S_IGN;
}
if (rootshell && new_act == S_DFL) {
switch (signo) {
case SIGINT:
if (iflag || minusc || sflag == 0)
new_act = S_CATCH;
break;
case SIGQUIT:
#if DEBUG
if (debug)
break;
#endif
/* man bash:
* "In all cases, bash ignores SIGQUIT. Non-builtin
* commands run by bash have signal handlers
* set to the values inherited by the shell
* from its parent". */
new_act = S_IGN;
break;
case SIGTERM:
if (iflag)
new_act = S_IGN;
break;
#if JOBS
case SIGTSTP:
case SIGTTOU:
if (mflag)
new_act = S_IGN;
break;
#endif
}
}
//TODO: if !rootshell, we reset SIGQUIT to DFL,
//whereas we have to restore it to what shell got on entry
//from the parent. See comment above
t = &sigmode[signo - 1];
cur_act = *t;
if (cur_act == 0) {
/* current setting is not yet known */
if (sigaction(signo, NULL, &act)) {
/* pretend it worked; maybe we should give a warning,
* but other shells don't. We don't alter sigmode,
* so we retry every time.
* btw, in Linux it never fails. --vda */
return;
}
if (act.sa_handler == SIG_IGN) {
cur_act = S_HARD_IGN;
if (mflag
&& (signo == SIGTSTP || signo == SIGTTIN || signo == SIGTTOU)
) {
cur_act = S_IGN; /* don't hard ignore these */
}
}
}
if (cur_act == S_HARD_IGN || cur_act == new_act)
return;
act.sa_handler = SIG_DFL;
switch (new_act) {
case S_CATCH:
act.sa_handler = signal_handler;
act.sa_flags = 0; /* matters only if !DFL and !IGN */
sigfillset(&act.sa_mask); /* ditto */
break;
case S_IGN:
act.sa_handler = SIG_IGN;
break;
}
sigaction_set(signo, &act);
*t = new_act;
}
/* mode flags for set_curjob */
#define CUR_DELETE 2
#define CUR_RUNNING 1
#define CUR_STOPPED 0
/* mode flags for dowait */
#define DOWAIT_NONBLOCK WNOHANG
#define DOWAIT_BLOCK 0
#if JOBS
/* pgrp of shell on invocation */
static int initialpgrp; //references:2
static int ttyfd = -1; //5
#endif
/* array of jobs */
static struct job *jobtab; //5
/* size of array */
static unsigned njobs; //4
/* current job */
static struct job *curjob; //lots
/* number of presumed living untracked jobs */
static int jobless; //4
static void
set_curjob(struct job *jp, unsigned mode)
{
struct job *jp1;
struct job **jpp, **curp;
/* first remove from list */
jpp = curp = &curjob;
do {
jp1 = *jpp;
if (jp1 == jp)
break;
jpp = &jp1->prev_job;
} while (1);
*jpp = jp1->prev_job;
/* Then re-insert in correct position */
jpp = curp;
switch (mode) {
default:
#if DEBUG
abort();
#endif
case CUR_DELETE:
/* job being deleted */
break;
case CUR_RUNNING:
/* newly created job or backgrounded job,
put after all stopped jobs. */
do {
jp1 = *jpp;
#if JOBS
if (!jp1 || jp1->state != JOBSTOPPED)
#endif
break;
jpp = &jp1->prev_job;
} while (1);
/* FALLTHROUGH */
#if JOBS
case CUR_STOPPED:
#endif
/* newly stopped job - becomes curjob */
jp->prev_job = *jpp;
*jpp = jp;
break;
}
}
#if JOBS || DEBUG
static int
jobno(const struct job *jp)
{
return jp - jobtab + 1;
}
#endif
/*
* Convert a job name to a job structure.
*/
#if !JOBS
#define getjob(name, getctl) getjob(name)
#endif
static struct job *
getjob(const char *name, int getctl)
{
struct job *jp;
struct job *found;
const char *err_msg = "%s: no such job";
unsigned num;
int c;
const char *p;
char *(*match)(const char *, const char *);
jp = curjob;
p = name;
if (!p)
goto currentjob;
if (*p != '%')
goto err;
c = *++p;
if (!c)
goto currentjob;
if (!p[1]) {
if (c == '+' || c == '%') {
currentjob:
err_msg = "No current job";
goto check;
}
if (c == '-') {
if (jp)
jp = jp->prev_job;
err_msg = "No previous job";
check:
if (!jp)
goto err;
goto gotit;
}
}
if (is_number(p)) {
num = atoi(p);
if (num < njobs) {
jp = jobtab + num - 1;
if (jp->used)
goto gotit;
goto err;
}
}
match = prefix;
if (*p == '?') {
match = strstr;
p++;
}
found = NULL;
while (jp) {
if (match(jp->ps[0].ps_cmd, p)) {
if (found)
goto err;
found = jp;
err_msg = "%s: ambiguous";
}
jp = jp->prev_job;
}
if (!found)
goto err;
jp = found;
gotit:
#if JOBS
err_msg = "job %s not created under job control";
if (getctl && jp->jobctl == 0)
goto err;
#endif
return jp;
err:
ash_msg_and_raise_error(err_msg, name);
}
/*
* Mark a job structure as unused.
*/
static void
freejob(struct job *jp)
{
struct procstat *ps;
int i;
INT_OFF;
for (i = jp->nprocs, ps = jp->ps; --i >= 0; ps++) {
if (ps->ps_cmd != nullstr)
free(ps->ps_cmd);
}
if (jp->ps != &jp->ps0)
free(jp->ps);
jp->used = 0;
set_curjob(jp, CUR_DELETE);
INT_ON;
}
#if JOBS
static void
xtcsetpgrp(int fd, pid_t pgrp)
{
if (tcsetpgrp(fd, pgrp))
ash_msg_and_raise_error("can't set tty process group (%m)");
}
/*
* Turn job control on and off.
*
* Note: This code assumes that the third arg to ioctl is a character
* pointer, which is true on Berkeley systems but not System V. Since
* System V doesn't have job control yet, this isn't a problem now.
*
* Called with interrupts off.
*/
static void
setjobctl(int on)
{
int fd;
int pgrp;
if (on == doing_jobctl || rootshell == 0)
return;
if (on) {
int ofd;
ofd = fd = open(_PATH_TTY, O_RDWR);
if (fd < 0) {
/* BTW, bash will try to open(ttyname(0)) if open("/dev/tty") fails.
* That sometimes helps to acquire controlling tty.
* Obviously, a workaround for bugs when someone
* failed to provide a controlling tty to bash! :) */
fd = 2;
while (!isatty(fd))
if (--fd < 0)
goto out;
}
fd = fcntl(fd, F_DUPFD, 10);
if (ofd >= 0)
close(ofd);
if (fd < 0)
goto out;
/* fd is a tty at this point */
close_on_exec_on(fd);
do { /* while we are in the background */
pgrp = tcgetpgrp(fd);
if (pgrp < 0) {
out:
ash_msg("can't access tty; job control turned off");
mflag = on = 0;
goto close;
}
if (pgrp == getpgrp())
break;
killpg(0, SIGTTIN);
} while (1);
initialpgrp = pgrp;
setsignal(SIGTSTP);
setsignal(SIGTTOU);
setsignal(SIGTTIN);
pgrp = rootpid;
setpgid(0, pgrp);
xtcsetpgrp(fd, pgrp);
} else {
/* turning job control off */
fd = ttyfd;
pgrp = initialpgrp;
/* was xtcsetpgrp, but this can make exiting ash
* loop forever if pty is already deleted */
tcsetpgrp(fd, pgrp);
setpgid(0, pgrp);
setsignal(SIGTSTP);
setsignal(SIGTTOU);
setsignal(SIGTTIN);
close:
if (fd >= 0)
close(fd);
fd = -1;
}
ttyfd = fd;
doing_jobctl = on;
}
static int FAST_FUNC
killcmd(int argc, char **argv)
{
int i = 1;
if (argv[1] && strcmp(argv[1], "-l") != 0) {
do {
if (argv[i][0] == '%') {
struct job *jp = getjob(argv[i], 0);
unsigned pid = jp->ps[0].ps_pid;
/* Enough space for ' -NNN<nul>' */
argv[i] = alloca(sizeof(int)*3 + 3);
/* kill_main has matching code to expect
* leading space. Needed to not confuse
* negative pids with "kill -SIGNAL_NO" syntax */
sprintf(argv[i], " -%u", pid);
}
} while (argv[++i]);
}
return kill_main(argc, argv);
}
static void
showpipe(struct job *jp /*, FILE *out*/)
{
struct procstat *ps;
struct procstat *psend;
psend = jp->ps + jp->nprocs;
for (ps = jp->ps + 1; ps < psend; ps++)
printf(" | %s", ps->ps_cmd);
outcslow('\n', stdout);
flush_stdout_stderr();
}
static int
restartjob(struct job *jp, int mode)
{
struct procstat *ps;
int i;
int status;
pid_t pgid;
INT_OFF;
if (jp->state == JOBDONE)
goto out;
jp->state = JOBRUNNING;
pgid = jp->ps[0].ps_pid;
if (mode == FORK_FG)
xtcsetpgrp(ttyfd, pgid);
killpg(pgid, SIGCONT);
ps = jp->ps;
i = jp->nprocs;
do {
if (WIFSTOPPED(ps->ps_status)) {
ps->ps_status = -1;
}
ps++;
} while (--i);
out:
status = (mode == FORK_FG) ? waitforjob(jp) : 0;
INT_ON;
return status;
}
static int FAST_FUNC
fg_bgcmd(int argc UNUSED_PARAM, char **argv)
{
struct job *jp;
int mode;
int retval;
mode = (**argv == 'f') ? FORK_FG : FORK_BG;
nextopt(nullstr);
argv = argptr;
do {
jp = getjob(*argv, 1);
if (mode == FORK_BG) {
set_curjob(jp, CUR_RUNNING);
printf("[%d] ", jobno(jp));
}
out1str(jp->ps[0].ps_cmd);
showpipe(jp /*, stdout*/);
retval = restartjob(jp, mode);
} while (*argv && *++argv);
return retval;
}
#endif
static int
sprint_status(char *s, int status, int sigonly)
{
int col;
int st;
col = 0;
if (!WIFEXITED(status)) {
#if JOBS
if (WIFSTOPPED(status))
st = WSTOPSIG(status);
else
#endif
st = WTERMSIG(status);
if (sigonly) {
if (st == SIGINT || st == SIGPIPE)
goto out;
#if JOBS
if (WIFSTOPPED(status))
goto out;
#endif
}
st &= 0x7f;
col = fmtstr(s, 32, strsignal(st));
if (WCOREDUMP(status)) {
col += fmtstr(s + col, 16, " (core dumped)");
}
} else if (!sigonly) {
st = WEXITSTATUS(status);
if (st)
col = fmtstr(s, 16, "Done(%d)", st);
else
col = fmtstr(s, 16, "Done");
}
out:
return col;
}
static int
dowait(int wait_flags, struct job *job)
{
int pid;
int status;
struct job *jp;
struct job *thisjob;
int state;
TRACE(("dowait(0x%x) called\n", wait_flags));
/* Do a wait system call. If job control is compiled in, we accept
* stopped processes. wait_flags may have WNOHANG, preventing blocking.
* NB: _not_ safe_waitpid, we need to detect EINTR */
if (doing_jobctl)
wait_flags |= WUNTRACED;
pid = waitpid(-1, &status, wait_flags);
TRACE(("wait returns pid=%d, status=0x%x, errno=%d(%s)\n",
pid, status, errno, strerror(errno)));
if (pid <= 0)
return pid;
INT_OFF;
thisjob = NULL;
for (jp = curjob; jp; jp = jp->prev_job) {
struct procstat *ps;
struct procstat *psend;
if (jp->state == JOBDONE)
continue;
state = JOBDONE;
ps = jp->ps;
psend = ps + jp->nprocs;
do {
if (ps->ps_pid == pid) {
TRACE(("Job %d: changing status of proc %d "
"from 0x%x to 0x%x\n",
jobno(jp), pid, ps->ps_status, status));
ps->ps_status = status;
thisjob = jp;
}
if (ps->ps_status == -1)
state = JOBRUNNING;
#if JOBS
if (state == JOBRUNNING)
continue;
if (WIFSTOPPED(ps->ps_status)) {
jp->stopstatus = ps->ps_status;
state = JOBSTOPPED;
}
#endif
} while (++ps < psend);
if (thisjob)
goto gotjob;
}
#if JOBS
if (!WIFSTOPPED(status))
#endif
jobless--;
goto out;
gotjob:
if (state != JOBRUNNING) {
thisjob->changed = 1;
if (thisjob->state != state) {
TRACE(("Job %d: changing state from %d to %d\n",
jobno(thisjob), thisjob->state, state));
thisjob->state = state;
#if JOBS
if (state == JOBSTOPPED) {
set_curjob(thisjob, CUR_STOPPED);
}
#endif
}
}
out:
INT_ON;
if (thisjob && thisjob == job) {
char s[48 + 1];
int len;
len = sprint_status(s, status, 1);
if (len) {
s[len] = '\n';
s[len + 1] = '\0';
out2str(s);
}
}
return pid;
}
static int
blocking_wait_with_raise_on_sig(void)
{
pid_t pid = dowait(DOWAIT_BLOCK, NULL);
if (pid <= 0 && pending_sig)
raise_exception(EXSIG);
return pid;
}
#if JOBS
static void
showjob(FILE *out, struct job *jp, int mode)
{
struct procstat *ps;
struct procstat *psend;
int col;
int indent_col;
char s[80];
ps = jp->ps;
if (mode & SHOW_ONLY_PGID) { /* jobs -p */
/* just output process (group) id of pipeline */
fprintf(out, "%d\n", ps->ps_pid);
return;
}
col = fmtstr(s, 16, "[%d] ", jobno(jp));
indent_col = col;
if (jp == curjob)
s[col - 3] = '+';
else if (curjob && jp == curjob->prev_job)
s[col - 3] = '-';
if (mode & SHOW_PIDS)
col += fmtstr(s + col, 16, "%d ", ps->ps_pid);
psend = ps + jp->nprocs;
if (jp->state == JOBRUNNING) {
strcpy(s + col, "Running");
col += sizeof("Running") - 1;
} else {
int status = psend[-1].ps_status;
if (jp->state == JOBSTOPPED)
status = jp->stopstatus;
col += sprint_status(s + col, status, 0);
}
/* By now, "[JOBID]* [maybe PID] STATUS" is printed */
/* This loop either prints "<cmd1> | <cmd2> | <cmd3>" line
* or prints several "PID | <cmdN>" lines,
* depending on SHOW_PIDS bit.
* We do not print status of individual processes
* between PID and <cmdN>. bash does it, but not very well:
* first line shows overall job status, not process status,
* making it impossible to know 1st process status.
*/
goto start;
do {
/* for each process */
s[0] = '\0';
col = 33;
if (mode & SHOW_PIDS)
col = fmtstr(s, 48, "\n%*c%d ", indent_col, ' ', ps->ps_pid) - 1;
start:
fprintf(out, "%s%*c%s%s",
s,
33 - col >= 0 ? 33 - col : 0, ' ',
ps == jp->ps ? "" : "| ",
ps->ps_cmd
);
} while (++ps != psend);
outcslow('\n', out);
jp->changed = 0;
if (jp->state == JOBDONE) {
TRACE(("showjob: freeing job %d\n", jobno(jp)));
freejob(jp);
}
}
/*
* Print a list of jobs. If "change" is nonzero, only print jobs whose
* statuses have changed since the last call to showjobs.
*/
static void
showjobs(FILE *out, int mode)
{
struct job *jp;
TRACE(("showjobs(0x%x) called\n", mode));
/* Handle all finished jobs */
while (dowait(DOWAIT_NONBLOCK, NULL) > 0)
continue;
for (jp = curjob; jp; jp = jp->prev_job) {
if (!(mode & SHOW_CHANGED) || jp->changed) {
showjob(out, jp, mode);
}
}
}
static int FAST_FUNC
jobscmd(int argc UNUSED_PARAM, char **argv)
{
int mode, m;
mode = 0;
while ((m = nextopt("lp")) != '\0') {
if (m == 'l')
mode |= SHOW_PIDS;
else
mode |= SHOW_ONLY_PGID;
}
argv = argptr;
if (*argv) {
do
showjob(stdout, getjob(*argv, 0), mode);
while (*++argv);
} else {
showjobs(stdout, mode);
}
return 0;
}
#endif /* JOBS */
/* Called only on finished or stopped jobs (no members are running) */
static int
getstatus(struct job *job)
{
int status;
int retval;
struct procstat *ps;
/* Fetch last member's status */
ps = job->ps + job->nprocs - 1;
status = ps->ps_status;
if (pipefail) {
/* "set -o pipefail" mode: use last _nonzero_ status */
while (status == 0 && --ps >= job->ps)
status = ps->ps_status;
}
retval = WEXITSTATUS(status);
if (!WIFEXITED(status)) {
#if JOBS
retval = WSTOPSIG(status);
if (!WIFSTOPPED(status))
#endif
{
/* XXX: limits number of signals */
retval = WTERMSIG(status);
#if JOBS
if (retval == SIGINT)
job->sigint = 1;
#endif
}
retval += 128;
}
TRACE(("getstatus: job %d, nproc %d, status 0x%x, retval 0x%x\n",
jobno(job), job->nprocs, status, retval));
return retval;
}
static int FAST_FUNC
waitcmd(int argc UNUSED_PARAM, char **argv)
{
struct job *job;
int retval;
struct job *jp;
if (pending_sig)
raise_exception(EXSIG);
nextopt(nullstr);
retval = 0;
argv = argptr;
if (!*argv) {
/* wait for all jobs */
for (;;) {
jp = curjob;
while (1) {
if (!jp) /* no running procs */
goto ret;
if (jp->state == JOBRUNNING)
break;
jp->waited = 1;
jp = jp->prev_job;
}
blocking_wait_with_raise_on_sig();
/* man bash:
* "When bash is waiting for an asynchronous command via
* the wait builtin, the reception of a signal for which a trap
* has been set will cause the wait builtin to return immediately
* with an exit status greater than 128, immediately after which
* the trap is executed."
*
* blocking_wait_with_raise_on_sig raises signal handlers
* if it gets no pid (pid < 0). However,
* if child sends us a signal *and immediately exits*,
* blocking_wait_with_raise_on_sig gets pid > 0
* and does not handle pending_sig. Check this case: */
if (pending_sig)
raise_exception(EXSIG);
}
}
retval = 127;
do {
if (**argv != '%') {
pid_t pid = number(*argv);
job = curjob;
while (1) {
if (!job)
goto repeat;
if (job->ps[job->nprocs - 1].ps_pid == pid)
break;
job = job->prev_job;
}
} else
job = getjob(*argv, 0);
/* loop until process terminated or stopped */
while (job->state == JOBRUNNING)
blocking_wait_with_raise_on_sig();
job->waited = 1;
retval = getstatus(job);
repeat: ;
} while (*++argv);
ret:
return retval;
}
static struct job *
growjobtab(void)
{
size_t len;
ptrdiff_t offset;
struct job *jp, *jq;
len = njobs * sizeof(*jp);
jq = jobtab;
jp = ckrealloc(jq, len + 4 * sizeof(*jp));
offset = (char *)jp - (char *)jq;
if (offset) {
/* Relocate pointers */
size_t l = len;
jq = (struct job *)((char *)jq + l);
while (l) {
l -= sizeof(*jp);
jq--;
#define joff(p) ((struct job *)((char *)(p) + l))
#define jmove(p) (p) = (void *)((char *)(p) + offset)
if (joff(jp)->ps == &jq->ps0)
jmove(joff(jp)->ps);
if (joff(jp)->prev_job)
jmove(joff(jp)->prev_job);
}
if (curjob)
jmove(curjob);
#undef joff
#undef jmove
}
njobs += 4;
jobtab = jp;
jp = (struct job *)((char *)jp + len);
jq = jp + 3;
do {
jq->used = 0;
} while (--jq >= jp);
return jp;
}
/*
* Return a new job structure.
* Called with interrupts off.
*/
static struct job *
makejob(/*union node *node,*/ int nprocs)
{
int i;
struct job *jp;
for (i = njobs, jp = jobtab; ; jp++) {
if (--i < 0) {
jp = growjobtab();
break;
}
if (jp->used == 0)
break;
if (jp->state != JOBDONE || !jp->waited)
continue;
#if JOBS
if (doing_jobctl)
continue;
#endif
freejob(jp);
break;
}
memset(jp, 0, sizeof(*jp));
#if JOBS
/* jp->jobctl is a bitfield.
* "jp->jobctl |= jobctl" likely to give awful code */
if (doing_jobctl)
jp->jobctl = 1;
#endif
jp->prev_job = curjob;
curjob = jp;
jp->used = 1;
jp->ps = &jp->ps0;
if (nprocs > 1) {
jp->ps = ckmalloc(nprocs * sizeof(struct procstat));
}
TRACE(("makejob(%d) returns %%%d\n", nprocs,
jobno(jp)));
return jp;
}
#if JOBS
/*
* Return a string identifying a command (to be printed by the
* jobs command).
*/
static char *cmdnextc;
static void
cmdputs(const char *s)
{
static const char vstype[VSTYPE + 1][3] = {
"", "}", "-", "+", "?", "=",
"%", "%%", "#", "##"
IF_ASH_BASH_COMPAT(, ":", "/", "//")
};
const char *p, *str;
char cc[2];
char *nextc;
unsigned char c;
unsigned char subtype = 0;
int quoted = 0;
cc[1] = '\0';
nextc = makestrspace((strlen(s) + 1) * 8, cmdnextc);
p = s;
while ((c = *p++) != '\0') {
str = NULL;
switch (c) {
case CTLESC:
c = *p++;
break;
case CTLVAR:
subtype = *p++;
if ((subtype & VSTYPE) == VSLENGTH)
str = "${#";
else
str = "${";
if (!(subtype & VSQUOTE) == !(quoted & 1))
goto dostr;
quoted ^= 1;
c = '"';
break;
case CTLENDVAR:
str = "\"}" + !(quoted & 1);
quoted >>= 1;
subtype = 0;
goto dostr;
case CTLBACKQ:
str = "$(...)";
goto dostr;
case CTLBACKQ+CTLQUOTE:
str = "\"$(...)\"";
goto dostr;
#if ENABLE_SH_MATH_SUPPORT
case CTLARI:
str = "$((";
goto dostr;
case CTLENDARI:
str = "))";
goto dostr;
#endif
case CTLQUOTEMARK:
quoted ^= 1;
c = '"';
break;
case '=':
if (subtype == 0)
break;
if ((subtype & VSTYPE) != VSNORMAL)
quoted <<= 1;
str = vstype[subtype & VSTYPE];
if (subtype & VSNUL)
c = ':';
else
goto checkstr;
break;
case '\'':
case '\\':
case '"':
case '$':
/* These can only happen inside quotes */
cc[0] = c;
str = cc;
c = '\\';
break;
default:
break;
}
USTPUTC(c, nextc);
checkstr:
if (!str)
continue;
dostr:
while ((c = *str++) != '\0') {
USTPUTC(c, nextc);
}
} /* while *p++ not NUL */
if (quoted & 1) {
USTPUTC('"', nextc);
}
*nextc = 0;
cmdnextc = nextc;
}
/* cmdtxt() and cmdlist() call each other */
static void cmdtxt(union node *n);
static void
cmdlist(union node *np, int sep)
{
for (; np; np = np->narg.next) {
if (!sep)
cmdputs(" ");
cmdtxt(np);
if (sep && np->narg.next)
cmdputs(" ");
}
}
static void
cmdtxt(union node *n)
{
union node *np;
struct nodelist *lp;
const char *p;
if (!n)
return;
switch (n->type) {
default:
#if DEBUG
abort();
#endif
case NPIPE:
lp = n->npipe.cmdlist;
for (;;) {
cmdtxt(lp->n);
lp = lp->next;
if (!lp)
break;
cmdputs(" | ");
}
break;
case NSEMI:
p = "; ";
goto binop;
case NAND:
p = " && ";
goto binop;
case NOR:
p = " || ";
binop:
cmdtxt(n->nbinary.ch1);
cmdputs(p);
n = n->nbinary.ch2;
goto donode;
case NREDIR:
case NBACKGND:
n = n->nredir.n;
goto donode;
case NNOT:
cmdputs("!");
n = n->nnot.com;
donode:
cmdtxt(n);
break;
case NIF:
cmdputs("if ");
cmdtxt(n->nif.test);
cmdputs("; then ");
if (n->nif.elsepart) {
cmdtxt(n->nif.ifpart);
cmdputs("; else ");
n = n->nif.elsepart;
} else {
n = n->nif.ifpart;
}
p = "; fi";
goto dotail;
case NSUBSHELL:
cmdputs("(");
n = n->nredir.n;
p = ")";
goto dotail;
case NWHILE:
p = "while ";
goto until;
case NUNTIL:
p = "until ";
until:
cmdputs(p);
cmdtxt(n->nbinary.ch1);
n = n->nbinary.ch2;
p = "; done";
dodo:
cmdputs("; do ");
dotail:
cmdtxt(n);
goto dotail2;
case NFOR:
cmdputs("for ");
cmdputs(n->nfor.var);
cmdputs(" in ");
cmdlist(n->nfor.args, 1);
n = n->nfor.body;
p = "; done";
goto dodo;
case NDEFUN:
cmdputs(n->narg.text);
p = "() { ... }";
goto dotail2;
case NCMD:
cmdlist(n->ncmd.args, 1);
cmdlist(n->ncmd.redirect, 0);
break;
case NARG:
p = n->narg.text;
dotail2:
cmdputs(p);
break;
case NHERE:
case NXHERE:
p = "<<...";
goto dotail2;
case NCASE:
cmdputs("case ");
cmdputs(n->ncase.expr->narg.text);
cmdputs(" in ");
for (np = n->ncase.cases; np; np = np->nclist.next) {
cmdtxt(np->nclist.pattern);
cmdputs(") ");
cmdtxt(np->nclist.body);
cmdputs(";; ");
}
p = "esac";
goto dotail2;
case NTO:
p = ">";
goto redir;
case NCLOBBER:
p = ">|";
goto redir;
case NAPPEND:
p = ">>";
goto redir;
#if ENABLE_ASH_BASH_COMPAT
case NTO2:
#endif
case NTOFD:
p = ">&";
goto redir;
case NFROM:
p = "<";
goto redir;
case NFROMFD:
p = "<&";
goto redir;
case NFROMTO:
p = "<>";
redir:
cmdputs(utoa(n->nfile.fd));
cmdputs(p);
if (n->type == NTOFD || n->type == NFROMFD) {
cmdputs(utoa(n->ndup.dupfd));
break;
}
n = n->nfile.fname;
goto donode;
}
}
static char *
commandtext(union node *n)
{
char *name;
STARTSTACKSTR(cmdnextc);
cmdtxt(n);
name = stackblock();
TRACE(("commandtext: name %p, end %p\n\t\"%s\"\n",
name, cmdnextc, cmdnextc));
return ckstrdup(name);
}
#endif /* JOBS */
/*
* Fork off a subshell. If we are doing job control, give the subshell its
* own process group. Jp is a job structure that the job is to be added to.
* N is the command that will be evaluated by the child. Both jp and n may
* be NULL. The mode parameter can be one of the following:
* FORK_FG - Fork off a foreground process.
* FORK_BG - Fork off a background process.
* FORK_NOJOB - Like FORK_FG, but don't give the process its own
* process group even if job control is on.
*
* When job control is turned off, background processes have their standard
* input redirected to /dev/null (except for the second and later processes
* in a pipeline).
*
* Called with interrupts off.
*/
/*
* Clear traps on a fork.
*/
static void
clear_traps(void)
{
char **tp;
for (tp = trap; tp < &trap[NSIG]; tp++) {
if (*tp && **tp) { /* trap not NULL or "" (SIG_IGN) */
INT_OFF;
if (trap_ptr == trap)
free(*tp);
/* else: it "belongs" to trap_ptr vector, don't free */
*tp = NULL;
if ((tp - trap) != 0)
setsignal(tp - trap);
INT_ON;
}
}
}
/* Lives far away from here, needed for forkchild */
static void closescript(void);
/* Called after fork(), in child */
static NOINLINE void
forkchild(struct job *jp, union node *n, int mode)
{
int oldlvl;
TRACE(("Child shell %d\n", getpid()));
oldlvl = shlvl;
shlvl++;
/* man bash: "Non-builtin commands run by bash have signal handlers
* set to the values inherited by the shell from its parent".
* Do we do it correctly? */
closescript();
if (mode == FORK_NOJOB /* is it `xxx` ? */
&& n && n->type == NCMD /* is it single cmd? */
/* && n->ncmd.args->type == NARG - always true? */
&& n->ncmd.args && strcmp(n->ncmd.args->narg.text, "trap") == 0
&& n->ncmd.args->narg.next == NULL /* "trap" with no arguments */
/* && n->ncmd.args->narg.backquote == NULL - do we need to check this? */
) {
TRACE(("Trap hack\n"));
/* Awful hack for `trap` or $(trap).
*
* http://www.opengroup.org/onlinepubs/009695399/utilities/trap.html
* contains an example where "trap" is executed in a subshell:
*
* save_traps=$(trap)
* ...
* eval "$save_traps"
*
* Standard does not say that "trap" in subshell shall print
* parent shell's traps. It only says that its output
* must have suitable form, but then, in the above example
* (which is not supposed to be normative), it implies that.
*
* bash (and probably other shell) does implement it
* (traps are reset to defaults, but "trap" still shows them),
* but as a result, "trap" logic is hopelessly messed up:
*
* # trap
* trap -- 'echo Ho' SIGWINCH <--- we have a handler
* # (trap) <--- trap is in subshell - no output (correct, traps are reset)
* # true | trap <--- trap is in subshell - no output (ditto)
* # echo `true | trap` <--- in subshell - output (but traps are reset!)
* trap -- 'echo Ho' SIGWINCH
* # echo `(trap)` <--- in subshell in subshell - output
* trap -- 'echo Ho' SIGWINCH
* # echo `true | (trap)` <--- in subshell in subshell in subshell - output!
* trap -- 'echo Ho' SIGWINCH
*
* The rules when to forget and when to not forget traps
* get really complex and nonsensical.
*
* Our solution: ONLY bare $(trap) or `trap` is special.
*/
/* Save trap handler strings for trap builtin to print */
trap_ptr = memcpy(xmalloc(sizeof(trap)), trap, sizeof(trap));
/* Fall through into clearing traps */
}
clear_traps();
#if JOBS
/* do job control only in root shell */
doing_jobctl = 0;
if (mode != FORK_NOJOB && jp->jobctl && !oldlvl) {
pid_t pgrp;
if (jp->nprocs == 0)
pgrp = getpid();
else
pgrp = jp->ps[0].ps_pid;
/* this can fail because we are doing it in the parent also */
setpgid(0, pgrp);
if (mode == FORK_FG)
xtcsetpgrp(ttyfd, pgrp);
setsignal(SIGTSTP);
setsignal(SIGTTOU);
} else
#endif
if (mode == FORK_BG) {
/* man bash: "When job control is not in effect,
* asynchronous commands ignore SIGINT and SIGQUIT" */
ignoresig(SIGINT);
ignoresig(SIGQUIT);
if (jp->nprocs == 0) {
close(0);
if (open(bb_dev_null, O_RDONLY) != 0)
ash_msg_and_raise_error("can't open '%s'", bb_dev_null);
}
}
if (!oldlvl) {
if (iflag) { /* why if iflag only? */
setsignal(SIGINT);
setsignal(SIGTERM);
}
/* man bash:
* "In all cases, bash ignores SIGQUIT. Non-builtin
* commands run by bash have signal handlers
* set to the values inherited by the shell
* from its parent".
* Take care of the second rule: */
setsignal(SIGQUIT);
}
#if JOBS
if (n && n->type == NCMD
&& n->ncmd.args && strcmp(n->ncmd.args->narg.text, "jobs") == 0
) {
TRACE(("Job hack\n"));
/* "jobs": we do not want to clear job list for it,
* instead we remove only _its_ own_ job from job list.
* This makes "jobs .... | cat" more useful.
*/
freejob(curjob);
return;
}
#endif
for (jp = curjob; jp; jp = jp->prev_job)
freejob(jp);
jobless = 0;
}
/* Called after fork(), in parent */
#if !JOBS
#define forkparent(jp, n, mode, pid) forkparent(jp, mode, pid)
#endif
static void
forkparent(struct job *jp, union node *n, int mode, pid_t pid)
{
TRACE(("In parent shell: child = %d\n", pid));
if (!jp) {
while (jobless && dowait(DOWAIT_NONBLOCK, NULL) > 0)
continue;
jobless++;
return;
}
#if JOBS
if (mode != FORK_NOJOB && jp->jobctl) {
int pgrp;
if (jp->nprocs == 0)
pgrp = pid;
else
pgrp = jp->ps[0].ps_pid;
/* This can fail because we are doing it in the child also */
setpgid(pid, pgrp);
}
#endif
if (mode == FORK_BG) {
backgndpid = pid; /* set $! */
set_curjob(jp, CUR_RUNNING);
}
if (jp) {
struct procstat *ps = &jp->ps[jp->nprocs++];
ps->ps_pid = pid;
ps->ps_status = -1;
ps->ps_cmd = nullstr;
#if JOBS
if (doing_jobctl && n)
ps->ps_cmd = commandtext(n);
#endif
}
}
static int
forkshell(struct job *jp, union node *n, int mode)
{
int pid;
TRACE(("forkshell(%%%d, %p, %d) called\n", jobno(jp), n, mode));
pid = fork();
if (pid < 0) {
TRACE(("Fork failed, errno=%d", errno));
if (jp)
freejob(jp);
ash_msg_and_raise_error("can't fork");
}
if (pid == 0) {
CLEAR_RANDOM_T(&random_gen); /* or else $RANDOM repeats in child */
forkchild(jp, n, mode);
} else {
forkparent(jp, n, mode, pid);
}
return pid;
}
/*
* Wait for job to finish.
*
* Under job control we have the problem that while a child process
* is running interrupts generated by the user are sent to the child
* but not to the shell. This means that an infinite loop started by
* an interactive user may be hard to kill. With job control turned off,
* an interactive user may place an interactive program inside a loop.
* If the interactive program catches interrupts, the user doesn't want
* these interrupts to also abort the loop. The approach we take here
* is to have the shell ignore interrupt signals while waiting for a
* foreground process to terminate, and then send itself an interrupt
* signal if the child process was terminated by an interrupt signal.
* Unfortunately, some programs want to do a bit of cleanup and then
* exit on interrupt; unless these processes terminate themselves by
* sending a signal to themselves (instead of calling exit) they will
* confuse this approach.
*
* Called with interrupts off.
*/
static int
waitforjob(struct job *jp)
{
int st;
TRACE(("waitforjob(%%%d) called\n", jobno(jp)));
INT_OFF;
while (jp->state == JOBRUNNING) {
/* In non-interactive shells, we _can_ get
* a keyboard signal here and be EINTRed,
* but we just loop back, waiting for command to complete.
*
* man bash:
* "If bash is waiting for a command to complete and receives
* a signal for which a trap has been set, the trap
* will not be executed until the command completes."
*
* Reality is that even if trap is not set, bash
* will not act on the signal until command completes.
* Try this. sleep5intoff.c:
* #include <signal.h>
* #include <unistd.h>
* int main() {
* sigset_t set;
* sigemptyset(&set);
* sigaddset(&set, SIGINT);
* sigaddset(&set, SIGQUIT);
* sigprocmask(SIG_BLOCK, &set, NULL);
* sleep(5);
* return 0;
* }
* $ bash -c './sleep5intoff; echo hi'
* ^C^C^C^C <--- pressing ^C once a second
* $ _
* $ bash -c './sleep5intoff; echo hi'
* ^\^\^\^\hi <--- pressing ^\ (SIGQUIT)
* $ _
*/
dowait(DOWAIT_BLOCK, jp);
}
INT_ON;
st = getstatus(jp);
#if JOBS
if (jp->jobctl) {
xtcsetpgrp(ttyfd, rootpid);
/*
* This is truly gross.
* If we're doing job control, then we did a TIOCSPGRP which
* caused us (the shell) to no longer be in the controlling
* session -- so we wouldn't have seen any ^C/SIGINT. So, we
* intuit from the subprocess exit status whether a SIGINT
* occurred, and if so interrupt ourselves. Yuck. - mycroft
*/
if (jp->sigint) /* TODO: do the same with all signals */
raise(SIGINT); /* ... by raise(jp->sig) instead? */
}
if (jp->state == JOBDONE)
#endif
freejob(jp);
return st;
}
/*
* return 1 if there are stopped jobs, otherwise 0
*/
static int
stoppedjobs(void)
{
struct job *jp;
int retval;
retval = 0;
if (job_warning)
goto out;
jp = curjob;
if (jp && jp->state == JOBSTOPPED) {
out2str("You have stopped jobs.\n");
job_warning = 2;
retval++;
}
out:
return retval;
}
/* ============ redir.c
*
* Code for dealing with input/output redirection.
*/
#define EMPTY -2 /* marks an unused slot in redirtab */
#define CLOSED -3 /* marks a slot of previously-closed fd */
/*
* Open a file in noclobber mode.
* The code was copied from bash.
*/
static int
noclobberopen(const char *fname)
{
int r, fd;
struct stat finfo, finfo2;
/*
* If the file exists and is a regular file, return an error
* immediately.
*/
r = stat(fname, &finfo);
if (r == 0 && S_ISREG(finfo.st_mode)) {
errno = EEXIST;
return -1;
}
/*
* If the file was not present (r != 0), make sure we open it
* exclusively so that if it is created before we open it, our open
* will fail. Make sure that we do not truncate an existing file.
* Note that we don't turn on O_EXCL unless the stat failed -- if the
* file was not a regular file, we leave O_EXCL off.
*/
if (r != 0)
return open(fname, O_WRONLY|O_CREAT|O_EXCL, 0666);
fd = open(fname, O_WRONLY|O_CREAT, 0666);
/* If the open failed, return the file descriptor right away. */
if (fd < 0)
return fd;
/*
* OK, the open succeeded, but the file may have been changed from a
* non-regular file to a regular file between the stat and the open.
* We are assuming that the O_EXCL open handles the case where FILENAME
* did not exist and is symlinked to an existing file between the stat
* and open.
*/
/*
* If we can open it and fstat the file descriptor, and neither check
* revealed that it was a regular file, and the file has not been
* replaced, return the file descriptor.
*/
if (fstat(fd, &finfo2) == 0 && !S_ISREG(finfo2.st_mode)
&& finfo.st_dev == finfo2.st_dev && finfo.st_ino == finfo2.st_ino)
return fd;
/* The file has been replaced. badness. */
close(fd);
errno = EEXIST;
return -1;
}
/*
* Handle here documents. Normally we fork off a process to write the
* data to a pipe. If the document is short, we can stuff the data in
* the pipe without forking.
*/
/* openhere needs this forward reference */
static void expandhere(union node *arg, int fd);
static int
openhere(union node *redir)
{
int pip[2];
size_t len = 0;
if (pipe(pip) < 0)
ash_msg_and_raise_error("pipe call failed");
if (redir->type == NHERE) {
len = strlen(redir->nhere.doc->narg.text);
if (len <= PIPE_BUF) {
full_write(pip[1], redir->nhere.doc->narg.text, len);
goto out;
}
}
if (forkshell((struct job *)NULL, (union node *)NULL, FORK_NOJOB) == 0) {
/* child */
close(pip[0]);
ignoresig(SIGINT); //signal(SIGINT, SIG_IGN);
ignoresig(SIGQUIT); //signal(SIGQUIT, SIG_IGN);
ignoresig(SIGHUP); //signal(SIGHUP, SIG_IGN);
ignoresig(SIGTSTP); //signal(SIGTSTP, SIG_IGN);
signal(SIGPIPE, SIG_DFL);
if (redir->type == NHERE)
full_write(pip[1], redir->nhere.doc->narg.text, len);
else /* NXHERE */
expandhere(redir->nhere.doc, pip[1]);
_exit(EXIT_SUCCESS);
}
out:
close(pip[1]);
return pip[0];
}
static int
openredirect(union node *redir)
{
char *fname;
int f;
switch (redir->nfile.type) {
case NFROM:
fname = redir->nfile.expfname;
f = open(fname, O_RDONLY);
if (f < 0)
goto eopen;
break;
case NFROMTO:
fname = redir->nfile.expfname;
f = open(fname, O_RDWR|O_CREAT|O_TRUNC, 0666);
if (f < 0)
goto ecreate;
break;
case NTO:
#if ENABLE_ASH_BASH_COMPAT
case NTO2:
#endif
/* Take care of noclobber mode. */
if (Cflag) {
fname = redir->nfile.expfname;
f = noclobberopen(fname);
if (f < 0)
goto ecreate;
break;
}
/* FALLTHROUGH */
case NCLOBBER:
fname = redir->nfile.expfname;
f = open(fname, O_WRONLY|O_CREAT|O_TRUNC, 0666);
if (f < 0)
goto ecreate;
break;
case NAPPEND:
fname = redir->nfile.expfname;
f = open(fname, O_WRONLY|O_CREAT|O_APPEND, 0666);
if (f < 0)
goto ecreate;
break;
default:
#if DEBUG
abort();
#endif
/* Fall through to eliminate warning. */
/* Our single caller does this itself */
// case NTOFD:
// case NFROMFD:
// f = -1;
// break;
case NHERE:
case NXHERE:
f = openhere(redir);
break;
}
return f;
ecreate:
ash_msg_and_raise_error("can't create %s: %s", fname, errmsg(errno, "nonexistent directory"));
eopen:
ash_msg_and_raise_error("can't open %s: %s", fname, errmsg(errno, "no such file"));
}
/*
* Copy a file descriptor to be >= to. Returns -1
* if the source file descriptor is closed, EMPTY if there are no unused
* file descriptors left.
*/
/* 0x800..00: bit to set in "to" to request dup2 instead of fcntl(F_DUPFD).
* old code was doing close(to) prior to copyfd() to achieve the same */
enum {
COPYFD_EXACT = (int)~(INT_MAX),
COPYFD_RESTORE = (int)((unsigned)COPYFD_EXACT >> 1),
};
static int
copyfd(int from, int to)
{
int newfd;
if (to & COPYFD_EXACT) {
to &= ~COPYFD_EXACT;
/*if (from != to)*/
newfd = dup2(from, to);
} else {
newfd = fcntl(from, F_DUPFD, to);
}
if (newfd < 0) {
if (errno == EMFILE)
return EMPTY;
/* Happens when source fd is not open: try "echo >&99" */
ash_msg_and_raise_error("%d: %m", from);
}
return newfd;
}
/* Struct def and variable are moved down to the first usage site */
struct two_fd_t {
int orig, copy;
};
struct redirtab {
struct redirtab *next;
int nullredirs;
int pair_count;
struct two_fd_t two_fd[];
};
#define redirlist (G_var.redirlist)
static int need_to_remember(struct redirtab *rp, int fd)
{
int i;
if (!rp) /* remembering was not requested */
return 0;
for (i = 0; i < rp->pair_count; i++) {
if (rp->two_fd[i].orig == fd) {
/* already remembered */
return 0;
}
}
return 1;
}
/* "hidden" fd is a fd used to read scripts, or a copy of such */
static int is_hidden_fd(struct redirtab *rp, int fd)
{
int i;
struct parsefile *pf;
if (fd == -1)
return 0;
pf = g_parsefile;
while (pf) {
if (fd == pf->fd) {
return 1;
}
pf = pf->prev;
}
if (!rp)
return 0;
fd |= COPYFD_RESTORE;
for (i = 0; i < rp->pair_count; i++) {
if (rp->two_fd[i].copy == fd) {
return 1;
}
}
return 0;
}
/*
* Process a list of redirection commands. If the REDIR_PUSH flag is set,
* old file descriptors are stashed away so that the redirection can be
* undone by calling popredir. If the REDIR_BACKQ flag is set, then the
* standard output, and the standard error if it becomes a duplicate of
* stdout, is saved in memory.
*/
/* flags passed to redirect */
#define REDIR_PUSH 01 /* save previous values of file descriptors */
#define REDIR_SAVEFD2 03 /* set preverrout */
static void
redirect(union node *redir, int flags)
{
struct redirtab *sv;
int sv_pos;
int i;
int fd;
int newfd;
int copied_fd2 = -1;
g_nullredirs++;
if (!redir) {
return;
}
sv = NULL;
sv_pos = 0;
INT_OFF;
if (flags & REDIR_PUSH) {
union node *tmp = redir;
do {
sv_pos++;
#if ENABLE_ASH_BASH_COMPAT
if (tmp->nfile.type == NTO2)
sv_pos++;
#endif
tmp = tmp->nfile.next;
} while (tmp);
sv = ckmalloc(sizeof(*sv) + sv_pos * sizeof(sv->two_fd[0]));
sv->next = redirlist;
sv->pair_count = sv_pos;
redirlist = sv;
sv->nullredirs = g_nullredirs - 1;
g_nullredirs = 0;
while (sv_pos > 0) {
sv_pos--;
sv->two_fd[sv_pos].orig = sv->two_fd[sv_pos].copy = EMPTY;
}
}
do {
fd = redir->nfile.fd;
if (redir->nfile.type == NTOFD || redir->nfile.type == NFROMFD) {
int right_fd = redir->ndup.dupfd;
/* redirect from/to same file descriptor? */
if (right_fd == fd)
continue;
/* echo >&10 and 10 is a fd opened to the sh script? */
if (is_hidden_fd(sv, right_fd)) {
errno = EBADF; /* as if it is closed */
ash_msg_and_raise_error("%d: %m", right_fd);
}
newfd = -1;
} else {
newfd = openredirect(redir); /* always >= 0 */
if (fd == newfd) {
/* Descriptor wasn't open before redirect.
* Mark it for close in the future */
if (need_to_remember(sv, fd)) {
goto remember_to_close;
}
continue;
}
}
#if ENABLE_ASH_BASH_COMPAT
redirect_more:
#endif
if (need_to_remember(sv, fd)) {
/* Copy old descriptor */
i = fcntl(fd, F_DUPFD, 10);
/* You'd expect copy to be CLOEXECed. Currently these extra "saved" fds
* are closed in popredir() in the child, preventing them from leaking
* into child. (popredir() also cleans up the mess in case of failures)
*/
if (i == -1) {
i = errno;
if (i != EBADF) {
/* Strange error (e.g. "too many files" EMFILE?) */
if (newfd >= 0)
close(newfd);
errno = i;
ash_msg_and_raise_error("%d: %m", fd);
/* NOTREACHED */
}
/* EBADF: it is not open - good, remember to close it */
remember_to_close:
i = CLOSED;
} else { /* fd is open, save its copy */
/* "exec fd>&-" should not close fds
* which point to script file(s).
* Force them to be restored afterwards */
if (is_hidden_fd(sv, fd))
i |= COPYFD_RESTORE;
}
if (fd == 2)
copied_fd2 = i;
sv->two_fd[sv_pos].orig = fd;
sv->two_fd[sv_pos].copy = i;
sv_pos++;
}
if (newfd < 0) {
/* NTOFD/NFROMFD: copy redir->ndup.dupfd to fd */
if (redir->ndup.dupfd < 0) { /* "fd>&-" */
/* Don't want to trigger debugging */
if (fd != -1)
close(fd);
} else {
copyfd(redir->ndup.dupfd, fd | COPYFD_EXACT);
}
} else if (fd != newfd) { /* move newfd to fd */
copyfd(newfd, fd | COPYFD_EXACT);
#if ENABLE_ASH_BASH_COMPAT
if (!(redir->nfile.type == NTO2 && fd == 2))
#endif
close(newfd);
}
#if ENABLE_ASH_BASH_COMPAT
if (redir->nfile.type == NTO2 && fd == 1) {
/* We already redirected it to fd 1, now copy it to 2 */
newfd = 1;
fd = 2;
goto redirect_more;
}
#endif
} while ((redir = redir->nfile.next) != NULL);
INT_ON;
if ((flags & REDIR_SAVEFD2) && copied_fd2 >= 0)
preverrout_fd = copied_fd2;
}
/*
* Undo the effects of the last redirection.
*/
static void
popredir(int drop, int restore)
{
struct redirtab *rp;
int i;
if (--g_nullredirs >= 0)
return;
INT_OFF;
rp = redirlist;
for (i = 0; i < rp->pair_count; i++) {
int fd = rp->two_fd[i].orig;
int copy = rp->two_fd[i].copy;
if (copy == CLOSED) {
if (!drop)
close(fd);
continue;
}
if (copy != EMPTY) {
if (!drop || (restore && (copy & COPYFD_RESTORE))) {
copy &= ~COPYFD_RESTORE;
/*close(fd);*/
copyfd(copy, fd | COPYFD_EXACT);
}
close(copy & ~COPYFD_RESTORE);
}
}
redirlist = rp->next;
g_nullredirs = rp->nullredirs;
free(rp);
INT_ON;
}
/*
* Undo all redirections. Called on error or interrupt.
*/
/*
* Discard all saved file descriptors.
*/
static void
clearredir(int drop)
{
for (;;) {
g_nullredirs = 0;
if (!redirlist)
break;
popredir(drop, /*restore:*/ 0);
}
}
static int
redirectsafe(union node *redir, int flags)
{
int err;
volatile int saveint;
struct jmploc *volatile savehandler = exception_handler;
struct jmploc jmploc;
SAVE_INT(saveint);
/* "echo 9>/dev/null; echo >&9; echo result: $?" - result should be 1, not 2! */
err = setjmp(jmploc.loc); // huh?? was = setjmp(jmploc.loc) * 2;
if (!err) {
exception_handler = &jmploc;
redirect(redir, flags);
}
exception_handler = savehandler;
if (err && exception_type != EXERROR)
longjmp(exception_handler->loc, 1);
RESTORE_INT(saveint);
return err;
}
/* ============ Routines to expand arguments to commands
*
* We have to deal with backquotes, shell variables, and file metacharacters.
*/
#if ENABLE_SH_MATH_SUPPORT
static arith_t
ash_arith(const char *s)
{
arith_eval_hooks_t math_hooks;
arith_t result;
int errcode = 0;
math_hooks.lookupvar = lookupvar;
math_hooks.setvar = setvar2;
math_hooks.endofname = endofname;
INT_OFF;
result = arith(s, &errcode, &math_hooks);
if (errcode < 0) {
if (errcode == -3)
ash_msg_and_raise_error("exponent less than 0");
if (errcode == -2)
ash_msg_and_raise_error("divide by zero");
if (errcode == -5)
ash_msg_and_raise_error("expression recursion loop detected");
raise_error_syntax(s);
}
INT_ON;
return result;
}
#endif
/*
* expandarg flags
*/
#define EXP_FULL 0x1 /* perform word splitting & file globbing */
#define EXP_TILDE 0x2 /* do normal tilde expansion */
#define EXP_VARTILDE 0x4 /* expand tildes in an assignment */
#define EXP_REDIR 0x8 /* file glob for a redirection (1 match only) */
#define EXP_CASE 0x10 /* keeps quotes around for CASE pattern */
#define EXP_RECORD 0x20 /* need to record arguments for ifs breakup */
#define EXP_VARTILDE2 0x40 /* expand tildes after colons only */
#define EXP_WORD 0x80 /* expand word in parameter expansion */
#define EXP_QWORD 0x100 /* expand word in quoted parameter expansion */
/*
* rmescape() flags
*/
#define RMESCAPE_ALLOC 0x1 /* Allocate a new string */
#define RMESCAPE_GLOB 0x2 /* Add backslashes for glob */
#define RMESCAPE_QUOTED 0x4 /* Remove CTLESC unless in quotes */
#define RMESCAPE_GROW 0x8 /* Grow strings instead of stalloc */
#define RMESCAPE_HEAP 0x10 /* Malloc strings instead of stalloc */
/*
* Structure specifying which parts of the string should be searched
* for IFS characters.
*/
struct ifsregion {
struct ifsregion *next; /* next region in list */
int begoff; /* offset of start of region */
int endoff; /* offset of end of region */
int nulonly; /* search for nul bytes only */
};
struct arglist {
struct strlist *list;
struct strlist **lastp;
};
/* output of current string */
static char *expdest;
/* list of back quote expressions */
static struct nodelist *argbackq;
/* first struct in list of ifs regions */
static struct ifsregion ifsfirst;
/* last struct in list */
static struct ifsregion *ifslastp;
/* holds expanded arg list */
static struct arglist exparg;
/*
* Our own itoa().
*/
static int
cvtnum(arith_t num)
{
int len;
expdest = makestrspace(32, expdest);
len = fmtstr(expdest, 32, arith_t_fmt, num);
STADJUST(len, expdest);
return len;
}
static size_t
esclen(const char *start, const char *p)
{
size_t esc = 0;
while (p > start && (unsigned char)*--p == CTLESC) {
esc++;
}
return esc;
}
/*
* Remove any CTLESC characters from a string.
*/
static char *
rmescapes(char *str, int flag)
{
static const char qchars[] ALIGN1 = { CTLESC, CTLQUOTEMARK, '\0' };
char *p, *q, *r;
unsigned inquotes;
unsigned protect_against_glob;
unsigned globbing;
p = strpbrk(str, qchars);
if (!p)
return str;
q = p;
r = str;
if (flag & RMESCAPE_ALLOC) {
size_t len = p - str;
size_t fulllen = len + strlen(p) + 1;
if (flag & RMESCAPE_GROW) {
int strloc = str - (char *)stackblock();
r = makestrspace(fulllen, expdest);
/* p and str may be invalidated by makestrspace */
str = (char *)stackblock() + strloc;
p = str + len;
} else if (flag & RMESCAPE_HEAP) {
r = ckmalloc(fulllen);
} else {
r = stalloc(fulllen);
}
q = r;
if (len > 0) {
q = (char *)memcpy(q, str, len) + len;
}
}
inquotes = (flag & RMESCAPE_QUOTED) ^ RMESCAPE_QUOTED;
globbing = flag & RMESCAPE_GLOB;
protect_against_glob = globbing;
while (*p) {
if ((unsigned char)*p == CTLQUOTEMARK) {
// TODO: if no RMESCAPE_QUOTED in flags, inquotes never becomes 0
// (alternates between RMESCAPE_QUOTED and ~RMESCAPE_QUOTED). Is it ok?
// Note: both inquotes and protect_against_glob only affect whether
// CTLESC,<ch> gets converted to <ch> or to \<ch>
inquotes = ~inquotes;
p++;
protect_against_glob = globbing;
continue;
}
if (*p == '\\') {
/* naked back slash */
protect_against_glob = 0;
goto copy;
}
if ((unsigned char)*p == CTLESC) {
p++;
if (protect_against_glob && inquotes && *p != '/') {
*q++ = '\\';
}
}
protect_against_glob = globbing;
copy:
*q++ = *p++;
}
*q = '\0';
if (flag & RMESCAPE_GROW) {
expdest = r;
STADJUST(q - r + 1, expdest);
}
return r;
}
#define pmatch(a, b) !fnmatch((a), (b), 0)
/*
* Prepare a pattern for a expmeta (internal glob(3)) call.
*
* Returns an stalloced string.
*/
static char *
preglob(const char *pattern, int quoted, int flag)
{
flag |= RMESCAPE_GLOB;
if (quoted) {
flag |= RMESCAPE_QUOTED;
}
return rmescapes((char *)pattern, flag);
}
/*
* Put a string on the stack.
*/
static void
memtodest(const char *p, size_t len, int syntax, int quotes)
{
char *q = expdest;
q = makestrspace(quotes ? len * 2 : len, q);
while (len--) {
unsigned char c = *p++;
if (c == '\0')
continue;
if (quotes) {
int n = SIT(c, syntax);
if (n == CCTL || n == CBACK)
USTPUTC(CTLESC, q);
}
USTPUTC(c, q);
}
expdest = q;
}
static void
strtodest(const char *p, int syntax, int quotes)
{
memtodest(p, strlen(p), syntax, quotes);
}
/*
* Record the fact that we have to scan this region of the
* string for IFS characters.
*/
static void
recordregion(int start, int end, int nulonly)
{
struct ifsregion *ifsp;
if (ifslastp == NULL) {
ifsp = &ifsfirst;
} else {
INT_OFF;
ifsp = ckzalloc(sizeof(*ifsp));
/*ifsp->next = NULL; - ckzalloc did it */
ifslastp->next = ifsp;
INT_ON;
}
ifslastp = ifsp;
ifslastp->begoff = start;
ifslastp->endoff = end;
ifslastp->nulonly = nulonly;
}
static void
removerecordregions(int endoff)
{
if (ifslastp == NULL)
return;
if (ifsfirst.endoff > endoff) {
while (ifsfirst.next != NULL) {
struct ifsregion *ifsp;
INT_OFF;
ifsp = ifsfirst.next->next;
free(ifsfirst.next);
ifsfirst.next = ifsp;
INT_ON;
}
if (ifsfirst.begoff > endoff)
ifslastp = NULL;
else {
ifslastp = &ifsfirst;
ifsfirst.endoff = endoff;
}
return;
}
ifslastp = &ifsfirst;
while (ifslastp->next && ifslastp->next->begoff < endoff)
ifslastp=ifslastp->next;
while (ifslastp->next != NULL) {
struct ifsregion *ifsp;
INT_OFF;
ifsp = ifslastp->next->next;
free(ifslastp->next);
ifslastp->next = ifsp;
INT_ON;
}
if (ifslastp->endoff > endoff)
ifslastp->endoff = endoff;
}
static char *
exptilde(char *startp, char *p, int flags)
{
unsigned char c;
char *name;
struct passwd *pw;
const char *home;
int quotes = flags & (EXP_FULL | EXP_CASE | EXP_REDIR);
int startloc;
name = p + 1;
while ((c = *++p) != '\0') {
switch (c) {
case CTLESC:
return startp;
case CTLQUOTEMARK:
return startp;
case ':':
if (flags & EXP_VARTILDE)
goto done;
break;
case '/':
case CTLENDVAR:
goto done;
}
}
done:
*p = '\0';
if (*name == '\0') {
home = lookupvar(homestr);
} else {
pw = getpwnam(name);
if (pw == NULL)
goto lose;
home = pw->pw_dir;
}
if (!home || !*home)
goto lose;
*p = c;
startloc = expdest - (char *)stackblock();
strtodest(home, SQSYNTAX, quotes);
recordregion(startloc, expdest - (char *)stackblock(), 0);
return p;
lose:
*p = c;
return startp;
}
/*
* Execute a command inside back quotes. If it's a builtin command, we
* want to save its output in a block obtained from malloc. Otherwise
* we fork off a subprocess and get the output of the command via a pipe.
* Should be called with interrupts off.
*/
struct backcmd { /* result of evalbackcmd */
int fd; /* file descriptor to read from */
int nleft; /* number of chars in buffer */
char *buf; /* buffer */
struct job *jp; /* job structure for command */
};
/* These forward decls are needed to use "eval" code for backticks handling: */
static uint8_t back_exitstatus; /* exit status of backquoted command */
#define EV_EXIT 01 /* exit after evaluating tree */
static void evaltree(union node *, int);
static void FAST_FUNC
evalbackcmd(union node *n, struct backcmd *result)
{
int saveherefd;
result->fd = -1;
result->buf = NULL;
result->nleft = 0;
result->jp = NULL;
if (n == NULL)
goto out;
saveherefd = herefd;
herefd = -1;
{
int pip[2];
struct job *jp;
if (pipe(pip) < 0)
ash_msg_and_raise_error("pipe call failed");
jp = makejob(/*n,*/ 1);
if (forkshell(jp, n, FORK_NOJOB) == 0) {
FORCE_INT_ON;
close(pip[0]);
if (pip[1] != 1) {
/*close(1);*/
copyfd(pip[1], 1 | COPYFD_EXACT);
close(pip[1]);
}
eflag = 0;
evaltree(n, EV_EXIT); /* actually evaltreenr... */
/* NOTREACHED */
}
close(pip[1]);
result->fd = pip[0];
result->jp = jp;
}
herefd = saveherefd;
out:
TRACE(("evalbackcmd done: fd=%d buf=0x%x nleft=%d jp=0x%x\n",
result->fd, result->buf, result->nleft, result->jp));
}
/*
* Expand stuff in backwards quotes.
*/
static void
expbackq(union node *cmd, int quoted, int quotes)
{
struct backcmd in;
int i;
char buf[128];
char *p;
char *dest;
int startloc;
int syntax = quoted ? DQSYNTAX : BASESYNTAX;
struct stackmark smark;
INT_OFF;
setstackmark(&smark);
dest = expdest;
startloc = dest - (char *)stackblock();
grabstackstr(dest);
evalbackcmd(cmd, &in);
popstackmark(&smark);
p = in.buf;
i = in.nleft;
if (i == 0)
goto read;
for (;;) {
memtodest(p, i, syntax, quotes);
read:
if (in.fd < 0)
break;
i = nonblock_safe_read(in.fd, buf, sizeof(buf));
TRACE(("expbackq: read returns %d\n", i));
if (i <= 0)
break;
p = buf;
}
free(in.buf);
if (in.fd >= 0) {
close(in.fd);
back_exitstatus = waitforjob(in.jp);
}
INT_ON;
/* Eat all trailing newlines */
dest = expdest;
for (; dest > (char *)stackblock() && dest[-1] == '\n';)
STUNPUTC(dest);
expdest = dest;
if (quoted == 0)
recordregion(startloc, dest - (char *)stackblock(), 0);
TRACE(("evalbackq: size=%d: \"%.*s\"\n",
(dest - (char *)stackblock()) - startloc,
(dest - (char *)stackblock()) - startloc,
stackblock() + startloc));
}
#if ENABLE_SH_MATH_SUPPORT
/*
* Expand arithmetic expression. Backup to start of expression,
* evaluate, place result in (backed up) result, adjust string position.
*/
static void
expari(int quotes)
{
char *p, *start;
int begoff;
int flag;
int len;
/* ifsfree(); */
/*
* This routine is slightly over-complicated for
* efficiency. Next we scan backwards looking for the
* start of arithmetic.
*/
start = stackblock();
p = expdest - 1;
*p = '\0';
p--;
do {
int esc;
while ((unsigned char)*p != CTLARI) {
p--;
#if DEBUG
if (p < start) {
ash_msg_and_raise_error("missing CTLARI (shouldn't happen)");
}
#endif
}
esc = esclen(start, p);
if (!(esc % 2)) {
break;
}
p -= esc + 1;
} while (1);
begoff = p - start;
removerecordregions(begoff);
flag = p[1];
expdest = p;
if (quotes)
rmescapes(p + 2, 0);
len = cvtnum(ash_arith(p + 2));
if (flag != '"')
recordregion(begoff, begoff + len, 0);
}
#endif
/* argstr needs it */
static char *evalvar(char *p, int flags, struct strlist *var_str_list);
/*
* Perform variable and command substitution. If EXP_FULL is set, output CTLESC
* characters to allow for further processing. Otherwise treat
* $@ like $* since no splitting will be performed.
*
* var_str_list (can be NULL) is a list of "VAR=val" strings which take precedence
* over shell varables. Needed for "A=a B=$A; echo $B" case - we use it
* for correct expansion of "B=$A" word.
*/
static void
argstr(char *p, int flags, struct strlist *var_str_list)
{
static const char spclchars[] ALIGN1 = {
'=',
':',
CTLQUOTEMARK,
CTLENDVAR,
CTLESC,
CTLVAR,
CTLBACKQ,
CTLBACKQ | CTLQUOTE,
#if ENABLE_SH_MATH_SUPPORT
CTLENDARI,
#endif
'\0'
};
const char *reject = spclchars;
int quotes = flags & (EXP_FULL | EXP_CASE | EXP_REDIR); /* do CTLESC */
int breakall = flags & EXP_WORD;
int inquotes;
size_t length;
int startloc;
if (!(flags & EXP_VARTILDE)) {
reject += 2;
} else if (flags & EXP_VARTILDE2) {
reject++;
}
inquotes = 0;
length = 0;
if (flags & EXP_TILDE) {
char *q;
flags &= ~EXP_TILDE;
tilde:
q = p;
if (*q == CTLESC && (flags & EXP_QWORD))
q++;
if (*q == '~')
p = exptilde(p, q, flags);
}
start:
startloc = expdest - (char *)stackblock();
for (;;) {
unsigned char c;
length += strcspn(p + length, reject);
c = p[length];
if (c) {
if (!(c & 0x80)
#if ENABLE_SH_MATH_SUPPORT
|| c == CTLENDARI
#endif
) {
/* c == '=' || c == ':' || c == CTLENDARI */
length++;
}
}
if (length > 0) {
int newloc;
expdest = stack_nputstr(p, length, expdest);
newloc = expdest - (char *)stackblock();
if (breakall && !inquotes && newloc > startloc) {
recordregion(startloc, newloc, 0);
}
startloc = newloc;
}
p += length + 1;
length = 0;
switch (c) {
case '\0':
goto breakloop;
case '=':
if (flags & EXP_VARTILDE2) {
p--;
continue;
}
flags |= EXP_VARTILDE2;
reject++;
/* fall through */
case ':':
/*
* sort of a hack - expand tildes in variable
* assignments (after the first '=' and after ':'s).
*/
if (*--p == '~') {
goto tilde;
}
continue;
}
switch (c) {
case CTLENDVAR: /* ??? */
goto breakloop;
case CTLQUOTEMARK:
/* "$@" syntax adherence hack */
if (!inquotes
&& memcmp(p, dolatstr, 4) == 0
&& ( p[4] == CTLQUOTEMARK
|| (p[4] == CTLENDVAR && p[5] == CTLQUOTEMARK)
)
) {
p = evalvar(p + 1, flags, /* var_str_list: */ NULL) + 1;
goto start;
}
inquotes = !inquotes;
addquote:
if (quotes) {
p--;
length++;
startloc++;
}
break;
case CTLESC:
startloc++;
length++;
goto addquote;
case CTLVAR:
p = evalvar(p, flags, var_str_list);
goto start;
case CTLBACKQ:
c = '\0';
case CTLBACKQ|CTLQUOTE:
expbackq(argbackq->n, c, quotes);
argbackq = argbackq->next;
goto start;
#if ENABLE_SH_MATH_SUPPORT
case CTLENDARI:
p--;
expari(quotes);
goto start;
#endif
}
}
breakloop:
;
}
static char *
scanleft(char *startp, char *rmesc, char *rmescend UNUSED_PARAM, char *str, int quotes,
int zero)
{
// This commented out code was added by James Simmons <jsimmons@infradead.org>
// as part of a larger change when he added support for ${var/a/b}.
// However, it broke # and % operators:
//
//var=ababcdcd
// ok bad
//echo ${var#ab} abcdcd abcdcd
//echo ${var##ab} abcdcd abcdcd
//echo ${var#a*b} abcdcd ababcdcd (!)
//echo ${var##a*b} cdcd cdcd
//echo ${var#?} babcdcd ababcdcd (!)
//echo ${var##?} babcdcd babcdcd
//echo ${var#*} ababcdcd babcdcd (!)
//echo ${var##*}
//echo ${var%cd} ababcd ababcd
//echo ${var%%cd} ababcd abab (!)
//echo ${var%c*d} ababcd ababcd
//echo ${var%%c*d} abab ababcdcd (!)
//echo ${var%?} ababcdc ababcdc
//echo ${var%%?} ababcdc ababcdcd (!)
//echo ${var%*} ababcdcd ababcdcd
//echo ${var%%*}
//
// Commenting it back out helped. Remove it completely if it really
// is not needed.
char *loc, *loc2; //, *full;
char c;
loc = startp;
loc2 = rmesc;
do {
int match; // = strlen(str);
const char *s = loc2;
c = *loc2;
if (zero) {
*loc2 = '\0';
s = rmesc;
}
match = pmatch(str, s); // this line was deleted
// // chop off end if its '*'
// full = strrchr(str, '*');
// if (full && full != str)
// match--;
//
// // If str starts with '*' replace with s.
// if ((*str == '*') && strlen(s) >= match) {
// full = xstrdup(s);
// strncpy(full+strlen(s)-match+1, str+1, match-1);
// } else
// full = xstrndup(str, match);
// match = strncmp(s, full, strlen(full));
// free(full);
//
*loc2 = c;
if (match) // if (!match)
return loc;
if (quotes && (unsigned char)*loc == CTLESC)
loc++;
loc++;
loc2++;
} while (c);
return 0;
}
static char *
scanright(char *startp, char *rmesc, char *rmescend, char *pattern, int quotes, int match_at_start)
{
#if !ENABLE_ASH_OPTIMIZE_FOR_SIZE
int try2optimize = match_at_start;
#endif
int esc = 0;
char *loc;
char *loc2;
/* If we called by "${v/pattern/repl}" or "${v//pattern/repl}":
* startp="escaped_value_of_v" rmesc="raw_value_of_v"
* rmescend=""(ptr to NUL in rmesc) pattern="pattern" quotes=match_at_start=1
* Logic:
* loc starts at NUL at the end of startp, loc2 starts at the end of rmesc,
* and on each iteration they go back two/one char until they reach the beginning.
* We try to find a match in "raw_value_of_v", "raw_value_of_", "raw_value_of" etc.
*/
/* TODO: document in what other circumstances we are called. */
for (loc = pattern - 1, loc2 = rmescend; loc >= startp; loc2--) {
int match;
char c = *loc2;
const char *s = loc2;
if (match_at_start) {
*loc2 = '\0';
s = rmesc;
}
match = pmatch(pattern, s);
//bb_error_msg("pmatch(pattern:'%s',s:'%s'):%d", pattern, s, match);
*loc2 = c;
if (match)
return loc;
#if !ENABLE_ASH_OPTIMIZE_FOR_SIZE
if (try2optimize) {
/* Maybe we can optimize this:
* if pattern ends with unescaped *, we can avoid checking
* shorter strings: if "foo*" doesnt match "raw_value_of_v",
* it wont match truncated "raw_value_of_" strings too.
*/
unsigned plen = strlen(pattern);
/* Does it end with "*"? */
if (plen != 0 && pattern[--plen] == '*') {
/* "xxxx*" is not escaped */
/* "xxx\*" is escaped */
/* "xx\\*" is not escaped */
/* "x\\\*" is escaped */
int slashes = 0;
while (plen != 0 && pattern[--plen] == '\\')
slashes++;
if (!(slashes & 1))
break; /* ends with unescaped "*" */
}
try2optimize = 0;
}
#endif
loc--;
if (quotes) {
if (--esc < 0) {
esc = esclen(startp, loc);
}
if (esc % 2) {
esc--;
loc--;
}
}
}
return 0;
}
static void varunset(const char *, const char *, const char *, int) NORETURN;
static void
varunset(const char *end, const char *var, const char *umsg, int varflags)
{
const char *msg;
const char *tail;
tail = nullstr;
msg = "parameter not set";
if (umsg) {
if ((unsigned char)*end == CTLENDVAR) {
if (varflags & VSNUL)
tail = " or null";
} else {
msg = umsg;
}
}
ash_msg_and_raise_error("%.*s: %s%s", end - var - 1, var, msg, tail);
}
#if ENABLE_ASH_BASH_COMPAT
static char *
parse_sub_pattern(char *arg, int inquotes)
{
char *idx, *repl = NULL;
unsigned char c;
idx = arg;
while (1) {
c = *arg;
if (!c)
break;
if (c == '/') {
/* Only the first '/' seen is our separator */
if (!repl) {
repl = idx + 1;
c = '\0';
}
}
*idx++ = c;
if (!inquotes && c == '\\' && arg[1] == '\\')
arg++; /* skip both \\, not just first one */
arg++;
}
*idx = c; /* NUL */
return repl;
}
#endif /* ENABLE_ASH_BASH_COMPAT */
static const char *
subevalvar(char *p, char *str, int strloc, int subtype,
int startloc, int varflags, int quotes, struct strlist *var_str_list)
{
struct nodelist *saveargbackq = argbackq;
char *startp;
char *loc;
char *rmesc, *rmescend;
IF_ASH_BASH_COMPAT(char *repl = NULL;)
IF_ASH_BASH_COMPAT(char null = '\0';)
IF_ASH_BASH_COMPAT(int pos, len, orig_len;)
int saveherefd = herefd;
int amount, workloc, resetloc;
int zero;
char *(*scan)(char*, char*, char*, char*, int, int);
herefd = -1;
argstr(p, (subtype != VSASSIGN && subtype != VSQUESTION) ? EXP_CASE : 0,
var_str_list);
STPUTC('\0', expdest);
herefd = saveherefd;
argbackq = saveargbackq;
startp = (char *)stackblock() + startloc;
switch (subtype) {
case VSASSIGN:
setvar(str, startp, 0);
amount = startp - expdest;
STADJUST(amount, expdest);
return startp;
#if ENABLE_ASH_BASH_COMPAT
case VSSUBSTR:
loc = str = stackblock() + strloc;
/* Read POS in ${var:POS:LEN} */
pos = atoi(loc); /* number(loc) errors out on "1:4" */
len = str - startp - 1;
/* *loc != '\0', guaranteed by parser */
if (quotes) {
char *ptr;
/* Adjust the length by the number of escapes */
for (ptr = startp; ptr < (str - 1); ptr++) {
if ((unsigned char)*ptr == CTLESC) {
len--;
ptr++;
}
}
}
orig_len = len;
if (*loc++ == ':') {
/* ${var::LEN} */
len = number(loc);
} else {
/* Skip POS in ${var:POS:LEN} */
len = orig_len;
while (*loc && *loc != ':') {
/* TODO?
* bash complains on: var=qwe; echo ${var:1a:123}
if (!isdigit(*loc))
ash_msg_and_raise_error(msg_illnum, str);
*/
loc++;
}
if (*loc++ == ':') {
len = number(loc);
}
}
if (pos >= orig_len) {
pos = 0;
len = 0;
}
if (len > (orig_len - pos))
len = orig_len - pos;
for (str = startp; pos; str++, pos--) {
if (quotes && (unsigned char)*str == CTLESC)
str++;
}
for (loc = startp; len; len--) {
if (quotes && (unsigned char)*str == CTLESC)
*loc++ = *str++;
*loc++ = *str++;
}
*loc = '\0';
amount = loc - expdest;
STADJUST(amount, expdest);
return loc;
#endif
case VSQUESTION:
varunset(p, str, startp, varflags);
/* NOTREACHED */
}
resetloc = expdest - (char *)stackblock();
/* We'll comeback here if we grow the stack while handling
* a VSREPLACE or VSREPLACEALL, since our pointers into the
* stack will need rebasing, and we'll need to remove our work
* areas each time
*/
IF_ASH_BASH_COMPAT(restart:)
amount = expdest - ((char *)stackblock() + resetloc);
STADJUST(-amount, expdest);
startp = (char *)stackblock() + startloc;
rmesc = startp;
rmescend = (char *)stackblock() + strloc;
if (quotes) {
rmesc = rmescapes(startp, RMESCAPE_ALLOC | RMESCAPE_GROW);
if (rmesc != startp) {
rmescend = expdest;
startp = (char *)stackblock() + startloc;
}
}
rmescend--;
str = (char *)stackblock() + strloc;
preglob(str, varflags & VSQUOTE, 0);
workloc = expdest - (char *)stackblock();
#if ENABLE_ASH_BASH_COMPAT
if (subtype == VSREPLACE || subtype == VSREPLACEALL) {
char *idx, *end;
if (!repl) {
repl = parse_sub_pattern(str, varflags & VSQUOTE);
if (!repl)
repl = &null;
}
/* If there's no pattern to match, return the expansion unmolested */
if (str[0] == '\0')
return 0;
len = 0;
idx = startp;
end = str - 1;
while (idx < end) {
try_to_match:
loc = scanright(idx, rmesc, rmescend, str, quotes, 1);
if (!loc) {
/* No match, advance */
char *restart_detect = stackblock();
skip_matching:
STPUTC(*idx, expdest);
if (quotes && (unsigned char)*idx == CTLESC) {
idx++;
len++;
STPUTC(*idx, expdest);
}
if (stackblock() != restart_detect)
goto restart;
idx++;
len++;
rmesc++;
/* continue; - prone to quadratic behavior, smarter code: */
if (idx >= end)
break;
if (str[0] == '*') {
/* Pattern is "*foo". If "*foo" does not match "long_string",
* it would never match "ong_string" etc, no point in trying.
*/
goto skip_matching;
}
goto try_to_match;
}
if (subtype == VSREPLACEALL) {
while (idx < loc) {
if (quotes && (unsigned char)*idx == CTLESC)
idx++;
idx++;
rmesc++;
}
} else {
idx = loc;
}
for (loc = repl; *loc; loc++) {
char *restart_detect = stackblock();
STPUTC(*loc, expdest);
if (stackblock() != restart_detect)
goto restart;
len++;
}
if (subtype == VSREPLACE) {
while (*idx) {
char *restart_detect = stackblock();
STPUTC(*idx, expdest);
if (stackblock() != restart_detect)
goto restart;
len++;
idx++;
}
break;
}
}
/* We've put the replaced text into a buffer at workloc, now
* move it to the right place and adjust the stack.
*/
startp = stackblock() + startloc;
STPUTC('\0', expdest);
memmove(startp, stackblock() + workloc, len);
startp[len++] = '\0';
amount = expdest - ((char *)stackblock() + startloc + len - 1);
STADJUST(-amount, expdest);
return startp;
}
#endif /* ENABLE_ASH_BASH_COMPAT */
subtype -= VSTRIMRIGHT;
#if DEBUG
if (subtype < 0 || subtype > 7)
abort();
#endif
/* zero = (subtype == VSTRIMLEFT || subtype == VSTRIMLEFTMAX) */
zero = subtype >> 1;
/* VSTRIMLEFT/VSTRIMRIGHTMAX -> scanleft */
scan = (subtype & 1) ^ zero ? scanleft : scanright;
loc = scan(startp, rmesc, rmescend, str, quotes, zero);
if (loc) {
if (zero) {
memmove(startp, loc, str - loc);
loc = startp + (str - loc) - 1;
}
*loc = '\0';
amount = loc - expdest;
STADJUST(amount, expdest);
}
return loc;
}
/*
* Add the value of a specialized variable to the stack string.
* name parameter (examples):
* ash -c 'echo $1' name:'1='
* ash -c 'echo $qwe' name:'qwe='
* ash -c 'echo $$' name:'$='
* ash -c 'echo ${$}' name:'$='
* ash -c 'echo ${$##q}' name:'$=q'
* ash -c 'echo ${#$}' name:'$='
* note: examples with bad shell syntax:
* ash -c 'echo ${#$1}' name:'$=1'
* ash -c 'echo ${#1#}' name:'1=#'
*/
static NOINLINE ssize_t
varvalue(char *name, int varflags, int flags, struct strlist *var_str_list)
{
const char *p;
int num;
int i;
int sepq = 0;
ssize_t len = 0;
int subtype = varflags & VSTYPE;
int quotes = flags & (EXP_FULL | EXP_CASE | EXP_REDIR);
int quoted = varflags & VSQUOTE;
int syntax = quoted ? DQSYNTAX : BASESYNTAX;
switch (*name) {
case '$':
num = rootpid;
goto numvar;
case '?':
num = exitstatus;
goto numvar;
case '#':
num = shellparam.nparam;
goto numvar;
case '!':
num = backgndpid;
if (num == 0)
return -1;
numvar:
len = cvtnum(num);
goto check_1char_name;
case '-':
expdest = makestrspace(NOPTS, expdest);
for (i = NOPTS - 1; i >= 0; i--) {
if (optlist[i]) {
USTPUTC(optletters(i), expdest);
len++;
}
}
check_1char_name:
#if 0
/* handles cases similar to ${#$1} */
if (name[2] != '\0')
raise_error_syntax("bad substitution");
#endif
break;
case '@': {
char **ap;
int sep;
if (quoted && (flags & EXP_FULL)) {
/* note: this is not meant as PEOF value */
sep = 1 << CHAR_BIT;
goto param;
}
/* fall through */
case '*':
sep = ifsset() ? (unsigned char)(ifsval()[0]) : ' ';
i = SIT(sep, syntax);
if (quotes && (i == CCTL || i == CBACK))
sepq = 1;
param:
ap = shellparam.p;
if (!ap)
return -1;
while ((p = *ap++) != NULL) {
size_t partlen;
partlen = strlen(p);
len += partlen;
if (!(subtype == VSPLUS || subtype == VSLENGTH))
memtodest(p, partlen, syntax, quotes);
if (*ap && sep) {
char *q;
len++;
if (subtype == VSPLUS || subtype == VSLENGTH) {
continue;
}
q = expdest;
if (sepq)
STPUTC(CTLESC, q);
/* note: may put NUL despite sep != 0
* (see sep = 1 << CHAR_BIT above) */
STPUTC(sep, q);
expdest = q;
}
}
return len;
} /* case '@' and '*' */
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
num = atoi(name); /* number(name) fails on ${N#str} etc */
if (num < 0 || num > shellparam.nparam)
return -1;
p = num ? shellparam.p[num - 1] : arg0;
goto value;
default:
/* NB: name has form "VAR=..." */
/* "A=a B=$A" case: var_str_list is a list of "A=a" strings
* which should be considered before we check variables. */
if (var_str_list) {
unsigned name_len = (strchrnul(name, '=') - name) + 1;
p = NULL;
do {
char *str, *eq;
str = var_str_list->text;
eq = strchr(str, '=');
if (!eq) /* stop at first non-assignment */
break;
eq++;
if (name_len == (unsigned)(eq - str)
&& strncmp(str, name, name_len) == 0
) {
p = eq;
/* goto value; - WRONG! */
/* think "A=1 A=2 B=$A" */
}
var_str_list = var_str_list->next;
} while (var_str_list);
if (p)
goto value;
}
p = lookupvar(name);
value:
if (!p)
return -1;
len = strlen(p);
if (!(subtype == VSPLUS || subtype == VSLENGTH))
memtodest(p, len, syntax, quotes);
return len;
}
if (subtype == VSPLUS || subtype == VSLENGTH)
STADJUST(-len, expdest);
return len;
}
/*
* Expand a variable, and return a pointer to the next character in the
* input string.
*/
static char *
evalvar(char *p, int flags, struct strlist *var_str_list)
{
char varflags;
char subtype;
char quoted;
char easy;
char *var;
int patloc;
int startloc;
ssize_t varlen;
varflags = (unsigned char) *p++;
subtype = varflags & VSTYPE;
quoted = varflags & VSQUOTE;
var = p;
easy = (!quoted || (*var == '@' && shellparam.nparam));
startloc = expdest - (char *)stackblock();
p = strchr(p, '=') + 1;
again:
varlen = varvalue(var, varflags, flags, var_str_list);
if (varflags & VSNUL)
varlen--;
if (subtype == VSPLUS) {
varlen = -1 - varlen;
goto vsplus;
}
if (subtype == VSMINUS) {
vsplus:
if (varlen < 0) {
argstr(
p, flags | EXP_TILDE |
(quoted ? EXP_QWORD : EXP_WORD),
var_str_list
);
goto end;
}
if (easy)
goto record;
goto end;
}
if (subtype == VSASSIGN || subtype == VSQUESTION) {
if (varlen < 0) {
if (subevalvar(p, var, /* strloc: */ 0,
subtype, startloc, varflags,
/* quotes: */ 0,
var_str_list)
) {
varflags &= ~VSNUL;
/*
* Remove any recorded regions beyond
* start of variable
*/
removerecordregions(startloc);
goto again;
}
goto end;
}
if (easy)
goto record;
goto end;
}
if (varlen < 0 && uflag)
varunset(p, var, 0, 0);
if (subtype == VSLENGTH) {
cvtnum(varlen > 0 ? varlen : 0);
goto record;
}
if (subtype == VSNORMAL) {
if (easy)
goto record;
goto end;
}
#if DEBUG
switch (subtype) {
case VSTRIMLEFT:
case VSTRIMLEFTMAX:
case VSTRIMRIGHT:
case VSTRIMRIGHTMAX:
#if ENABLE_ASH_BASH_COMPAT
case VSSUBSTR:
case VSREPLACE:
case VSREPLACEALL:
#endif
break;
default:
abort();
}
#endif
if (varlen >= 0) {
/*
* Terminate the string and start recording the pattern
* right after it
*/
STPUTC('\0', expdest);
patloc = expdest - (char *)stackblock();
if (0 == subevalvar(p, /* str: */ NULL, patloc, subtype,
startloc, varflags,
//TODO: | EXP_REDIR too? All other such places do it too
/* quotes: */ flags & (EXP_FULL | EXP_CASE),
var_str_list)
) {
int amount = expdest - (
(char *)stackblock() + patloc - 1
);
STADJUST(-amount, expdest);
}
/* Remove any recorded regions beyond start of variable */
removerecordregions(startloc);
record:
recordregion(startloc, expdest - (char *)stackblock(), quoted);
}
end:
if (subtype != VSNORMAL) { /* skip to end of alternative */
int nesting = 1;
for (;;) {
unsigned char c = *p++;
if (c == CTLESC)
p++;
else if (c == CTLBACKQ || c == (CTLBACKQ|CTLQUOTE)) {
if (varlen >= 0)
argbackq = argbackq->next;
} else if (c == CTLVAR) {
if ((*p++ & VSTYPE) != VSNORMAL)
nesting++;
} else if (c == CTLENDVAR) {
if (--nesting == 0)
break;
}
}
}
return p;
}
/*
* Break the argument string into pieces based upon IFS and add the
* strings to the argument list. The regions of the string to be
* searched for IFS characters have been stored by recordregion.
*/
static void
ifsbreakup(char *string, struct arglist *arglist)
{
struct ifsregion *ifsp;
struct strlist *sp;
char *start;
char *p;
char *q;
const char *ifs, *realifs;
int ifsspc;
int nulonly;
start = string;
if (ifslastp != NULL) {
ifsspc = 0;
nulonly = 0;
realifs = ifsset() ? ifsval() : defifs;
ifsp = &ifsfirst;
do {
p = string + ifsp->begoff;
nulonly = ifsp->nulonly;
ifs = nulonly ? nullstr : realifs;
ifsspc = 0;
while (p < string + ifsp->endoff) {
q = p;
if ((unsigned char)*p == CTLESC)
p++;
if (!strchr(ifs, *p)) {
p++;
continue;
}
if (!nulonly)
ifsspc = (strchr(defifs, *p) != NULL);
/* Ignore IFS whitespace at start */
if (q == start && ifsspc) {
p++;
start = p;
continue;
}
*q = '\0';
sp = stzalloc(sizeof(*sp));
sp->text = start;
*arglist->lastp = sp;
arglist->lastp = &sp->next;
p++;
if (!nulonly) {
for (;;) {
if (p >= string + ifsp->endoff) {
break;
}
q = p;
if ((unsigned char)*p == CTLESC)
p++;
if (strchr(ifs, *p) == NULL) {
p = q;
break;
}
if (strchr(defifs, *p) == NULL) {
if (ifsspc) {
p++;
ifsspc = 0;
} else {
p = q;
break;
}
} else
p++;
}
}
start = p;
} /* while */
ifsp = ifsp->next;
} while (ifsp != NULL);
if (nulonly)
goto add;
}
if (!*start)
return;
add:
sp = stzalloc(sizeof(*sp));
sp->text = start;
*arglist->lastp = sp;
arglist->lastp = &sp->next;
}
static void
ifsfree(void)
{
struct ifsregion *p;
INT_OFF;
p = ifsfirst.next;
do {
struct ifsregion *ifsp;
ifsp = p->next;
free(p);
p = ifsp;
} while (p);
ifslastp = NULL;
ifsfirst.next = NULL;
INT_ON;
}
/*
* Add a file name to the list.
*/
static void
addfname(const char *name)
{
struct strlist *sp;
sp = stzalloc(sizeof(*sp));
sp->text = ststrdup(name);
*exparg.lastp = sp;
exparg.lastp = &sp->next;
}
static char *expdir;
/*
* Do metacharacter (i.e. *, ?, [...]) expansion.
*/
static void
expmeta(char *enddir, char *name)
{
char *p;
const char *cp;
char *start;
char *endname;
int metaflag;
struct stat statb;
DIR *dirp;
struct dirent *dp;
int atend;
int matchdot;
metaflag = 0;
start = name;
for (p = name; *p; p++) {
if (*p == '*' || *p == '?')
metaflag = 1;
else if (*p == '[') {
char *q = p + 1;
if (*q == '!')
q++;
for (;;) {
if (*q == '\\')
q++;
if (*q == '/' || *q == '\0')
break;
if (*++q == ']') {
metaflag = 1;
break;
}
}
} else if (*p == '\\')
p++;
else if (*p == '/') {
if (metaflag)
goto out;
start = p + 1;
}
}
out:
if (metaflag == 0) { /* we've reached the end of the file name */
if (enddir != expdir)
metaflag++;
p = name;
do {
if (*p == '\\')
p++;
*enddir++ = *p;
} while (*p++);
if (metaflag == 0 || lstat(expdir, &statb) >= 0)
addfname(expdir);
return;
}
endname = p;
if (name < start) {
p = name;
do {
if (*p == '\\')
p++;
*enddir++ = *p++;
} while (p < start);
}
if (enddir == expdir) {
cp = ".";
} else if (enddir == expdir + 1 && *expdir == '/') {
cp = "/";
} else {
cp = expdir;
enddir[-1] = '\0';
}
dirp = opendir(cp);
if (dirp == NULL)
return;
if (enddir != expdir)
enddir[-1] = '/';
if (*endname == 0) {
atend = 1;
} else {
atend = 0;
*endname++ = '\0';
}
matchdot = 0;
p = start;
if (*p == '\\')
p++;
if (*p == '.')
matchdot++;
while (!pending_int && (dp = readdir(dirp)) != NULL) {
if (dp->d_name[0] == '.' && !matchdot)
continue;
if (pmatch(start, dp->d_name)) {
if (atend) {
strcpy(enddir, dp->d_name);
addfname(expdir);
} else {
for (p = enddir, cp = dp->d_name; (*p++ = *cp++) != '\0';)
continue;
p[-1] = '/';
expmeta(p, endname);
}
}
}
closedir(dirp);
if (!atend)
endname[-1] = '/';
}
static struct strlist *
msort(struct strlist *list, int len)
{
struct strlist *p, *q = NULL;
struct strlist **lpp;
int half;
int n;
if (len <= 1)
return list;
half = len >> 1;
p = list;
for (n = half; --n >= 0;) {
q = p;
p = p->next;
}
q->next = NULL; /* terminate first half of list */
q = msort(list, half); /* sort first half of list */
p = msort(p, len - half); /* sort second half */
lpp = &list;
for (;;) {
#if ENABLE_LOCALE_SUPPORT
if (strcoll(p->text, q->text) < 0)
#else
if (strcmp(p->text, q->text) < 0)
#endif
{
*lpp = p;
lpp = &p->next;
p = *lpp;
if (p == NULL) {
*lpp = q;
break;
}
} else {
*lpp = q;
lpp = &q->next;
q = *lpp;
if (q == NULL) {
*lpp = p;
break;
}
}
}
return list;
}
/*
* Sort the results of file name expansion. It calculates the number of
* strings to sort and then calls msort (short for merge sort) to do the
* work.
*/
static struct strlist *
expsort(struct strlist *str)
{
int len;
struct strlist *sp;
len = 0;
for (sp = str; sp; sp = sp->next)
len++;
return msort(str, len);
}
static void
expandmeta(struct strlist *str /*, int flag*/)
{
static const char metachars[] ALIGN1 = {
'*', '?', '[', 0
};
/* TODO - EXP_REDIR */
while (str) {
struct strlist **savelastp;
struct strlist *sp;
char *p;
if (fflag)
goto nometa;
if (!strpbrk(str->text, metachars))
goto nometa;
savelastp = exparg.lastp;
INT_OFF;
p = preglob(str->text, 0, RMESCAPE_ALLOC | RMESCAPE_HEAP);
{
int i = strlen(str->text);
expdir = ckmalloc(i < 2048 ? 2048 : i); /* XXX */
}
expmeta(expdir, p);
free(expdir);
if (p != str->text)
free(p);
INT_ON;
if (exparg.lastp == savelastp) {
/*
* no matches
*/
nometa:
*exparg.lastp = str;
rmescapes(str->text, 0);
exparg.lastp = &str->next;
} else {
*exparg.lastp = NULL;
*savelastp = sp = expsort(*savelastp);
while (sp->next != NULL)
sp = sp->next;
exparg.lastp = &sp->next;
}
str = str->next;
}
}
/*
* Perform variable substitution and command substitution on an argument,
* placing the resulting list of arguments in arglist. If EXP_FULL is true,
* perform splitting and file name expansion. When arglist is NULL, perform
* here document expansion.
*/
static void
expandarg(union node *arg, struct arglist *arglist, int flag)
{
struct strlist *sp;
char *p;
argbackq = arg->narg.backquote;
STARTSTACKSTR(expdest);
ifsfirst.next = NULL;
ifslastp = NULL;
argstr(arg->narg.text, flag,
/* var_str_list: */ arglist ? arglist->list : NULL);
p = _STPUTC('\0', expdest);
expdest = p - 1;
if (arglist == NULL) {
return; /* here document expanded */
}
p = grabstackstr(p);
exparg.lastp = &exparg.list;
/*
* TODO - EXP_REDIR
*/
if (flag & EXP_FULL) {
ifsbreakup(p, &exparg);
*exparg.lastp = NULL;
exparg.lastp = &exparg.list;
expandmeta(exparg.list /*, flag*/);
} else {
if (flag & EXP_REDIR) /*XXX - for now, just remove escapes */
rmescapes(p, 0);
sp = stzalloc(sizeof(*sp));
sp->text = p;
*exparg.lastp = sp;
exparg.lastp = &sp->next;
}
if (ifsfirst.next)
ifsfree();
*exparg.lastp = NULL;
if (exparg.list) {
*arglist->lastp = exparg.list;
arglist->lastp = exparg.lastp;
}
}
/*
* Expand shell variables and backquotes inside a here document.
*/
static void
expandhere(union node *arg, int fd)
{
herefd = fd;
expandarg(arg, (struct arglist *)NULL, 0);
full_write(fd, stackblock(), expdest - (char *)stackblock());
}
/*
* Returns true if the pattern matches the string.
*/
static int
patmatch(char *pattern, const char *string)
{
return pmatch(preglob(pattern, 0, 0), string);
}
/*
* See if a pattern matches in a case statement.
*/
static int
casematch(union node *pattern, char *val)
{
struct stackmark smark;
int result;
setstackmark(&smark);
argbackq = pattern->narg.backquote;
STARTSTACKSTR(expdest);
ifslastp = NULL;
argstr(pattern->narg.text, EXP_TILDE | EXP_CASE,
/* var_str_list: */ NULL);
STACKSTRNUL(expdest);
result = patmatch(stackblock(), val);
popstackmark(&smark);
return result;
}
/* ============ find_command */
struct builtincmd {
const char *name;
int (*builtin)(int, char **) FAST_FUNC;
/* unsigned flags; */
};
#define IS_BUILTIN_SPECIAL(b) ((b)->name[0] & 1)
/* "regular" builtins always take precedence over commands,
* regardless of PATH=....%builtin... position */
#define IS_BUILTIN_REGULAR(b) ((b)->name[0] & 2)
#define IS_BUILTIN_ASSIGN(b) ((b)->name[0] & 4)
struct cmdentry {
smallint cmdtype; /* CMDxxx */
union param {
int index;
/* index >= 0 for commands without path (slashes) */
/* (TODO: what exactly does the value mean? PATH position?) */
/* index == -1 for commands with slashes */
/* index == (-2 - applet_no) for NOFORK applets */
const struct builtincmd *cmd;
struct funcnode *func;
} u;
};
/* values of cmdtype */
#define CMDUNKNOWN -1 /* no entry in table for command */
#define CMDNORMAL 0 /* command is an executable program */
#define CMDFUNCTION 1 /* command is a shell function */
#define CMDBUILTIN 2 /* command is a shell builtin */
/* action to find_command() */
#define DO_ERR 0x01 /* prints errors */
#define DO_ABS 0x02 /* checks absolute paths */
#define DO_NOFUNC 0x04 /* don't return shell functions, for command */
#define DO_ALTPATH 0x08 /* using alternate path */
#define DO_ALTBLTIN 0x20 /* %builtin in alt. path */
static void find_command(char *, struct cmdentry *, int, const char *);
/* ============ Hashing commands */
/*
* When commands are first encountered, they are entered in a hash table.
* This ensures that a full path search will not have to be done for them
* on each invocation.
*
* We should investigate converting to a linear search, even though that
* would make the command name "hash" a misnomer.
*/
struct tblentry {
struct tblentry *next; /* next entry in hash chain */
union param param; /* definition of builtin function */
smallint cmdtype; /* CMDxxx */
char rehash; /* if set, cd done since entry created */
char cmdname[1]; /* name of command */
};
static struct tblentry **cmdtable;
#define INIT_G_cmdtable() do { \
cmdtable = xzalloc(CMDTABLESIZE * sizeof(cmdtable[0])); \
} while (0)
static int builtinloc = -1; /* index in path of %builtin, or -1 */
static void
tryexec(IF_FEATURE_SH_STANDALONE(int applet_no,) char *cmd, char **argv, char **envp)
{
int repeated = 0;
#if ENABLE_FEATURE_SH_STANDALONE
if (applet_no >= 0) {
if (APPLET_IS_NOEXEC(applet_no)) {
while (*envp)
putenv(*envp++);
run_applet_no_and_exit(applet_no, argv);
}
/* re-exec ourselves with the new arguments */
execve(bb_busybox_exec_path, argv, envp);
/* If they called chroot or otherwise made the binary no longer
* executable, fall through */
}
#endif
repeat:
#ifdef SYSV
do {
execve(cmd, argv, envp);
} while (errno == EINTR);
#else
execve(cmd, argv, envp);
#endif
if (repeated) {
free(argv);
return;
}
if (errno == ENOEXEC) {
char **ap;
char **new;
for (ap = argv; *ap; ap++)
continue;
ap = new = ckmalloc((ap - argv + 2) * sizeof(ap[0]));
ap[1] = cmd;
ap[0] = cmd = (char *)DEFAULT_SHELL;
ap += 2;
argv++;
while ((*ap++ = *argv++) != NULL)
continue;
argv = new;
repeated++;
goto repeat;
}
}
/*
* Exec a program. Never returns. If you change this routine, you may
* have to change the find_command routine as well.
*/
static void shellexec(char **, const char *, int) NORETURN;
static void
shellexec(char **argv, const char *path, int idx)
{
char *cmdname;
int e;
char **envp;
int exerrno;
#if ENABLE_FEATURE_SH_STANDALONE
int applet_no = -1;
#endif
clearredir(/*drop:*/ 1);
envp = listvars(VEXPORT, VUNSET, 0);
if (strchr(argv[0], '/') != NULL
#if ENABLE_FEATURE_SH_STANDALONE
|| (applet_no = find_applet_by_name(argv[0])) >= 0
#endif
) {
tryexec(IF_FEATURE_SH_STANDALONE(applet_no,) argv[0], argv, envp);
e = errno;
} else {
e = ENOENT;
while ((cmdname = path_advance(&path, argv[0])) != NULL) {
if (--idx < 0 && pathopt == NULL) {
tryexec(IF_FEATURE_SH_STANDALONE(-1,) cmdname, argv, envp);
if (errno != ENOENT && errno != ENOTDIR)
e = errno;
}
stunalloc(cmdname);
}
}
/* Map to POSIX errors */
switch (e) {
case EACCES:
exerrno = 126;
break;
case ENOENT:
exerrno = 127;
break;
default:
exerrno = 2;
break;
}
exitstatus = exerrno;
TRACE(("shellexec failed for %s, errno %d, suppress_int %d\n",
argv[0], e, suppress_int));
ash_msg_and_raise(EXEXEC, "%s: %s", argv[0], errmsg(e, "not found"));
/* NOTREACHED */
}
static void
printentry(struct tblentry *cmdp)
{
int idx;
const char *path;
char *name;
idx = cmdp->param.index;
path = pathval();
do {
name = path_advance(&path, cmdp->cmdname);
stunalloc(name);
} while (--idx >= 0);
out1fmt("%s%s\n", name, (cmdp->rehash ? "*" : nullstr));
}
/*
* Clear out command entries. The argument specifies the first entry in
* PATH which has changed.
*/
static void
clearcmdentry(int firstchange)
{
struct tblentry **tblp;
struct tblentry **pp;
struct tblentry *cmdp;
INT_OFF;
for (tblp = cmdtable; tblp < &cmdtable[CMDTABLESIZE]; tblp++) {
pp = tblp;
while ((cmdp = *pp) != NULL) {
if ((cmdp->cmdtype == CMDNORMAL &&
cmdp->param.index >= firstchange)
|| (cmdp->cmdtype == CMDBUILTIN &&
builtinloc >= firstchange)
) {
*pp = cmdp->next;
free(cmdp);
} else {
pp = &cmdp->next;
}
}
}
INT_ON;
}
/*
* Locate a command in the command hash table. If "add" is nonzero,
* add the command to the table if it is not already present. The
* variable "lastcmdentry" is set to point to the address of the link
* pointing to the entry, so that delete_cmd_entry can delete the
* entry.
*
* Interrupts must be off if called with add != 0.
*/
static struct tblentry **lastcmdentry;
static struct tblentry *
cmdlookup(const char *name, int add)
{
unsigned int hashval;
const char *p;
struct tblentry *cmdp;
struct tblentry **pp;
p = name;
hashval = (unsigned char)*p << 4;
while (*p)
hashval += (unsigned char)*p++;
hashval &= 0x7FFF;
pp = &cmdtable[hashval % CMDTABLESIZE];
for (cmdp = *pp; cmdp; cmdp = cmdp->next) {
if (strcmp(cmdp->cmdname, name) == 0)
break;
pp = &cmdp->next;
}
if (add && cmdp == NULL) {
cmdp = *pp = ckzalloc(sizeof(struct tblentry)
+ strlen(name)
/* + 1 - already done because
* tblentry::cmdname is char[1] */);
/*cmdp->next = NULL; - ckzalloc did it */
cmdp->cmdtype = CMDUNKNOWN;
strcpy(cmdp->cmdname, name);
}
lastcmdentry = pp;
return cmdp;
}
/*
* Delete the command entry returned on the last lookup.
*/
static void
delete_cmd_entry(void)
{
struct tblentry *cmdp;
INT_OFF;
cmdp = *lastcmdentry;
*lastcmdentry = cmdp->next;
if (cmdp->cmdtype == CMDFUNCTION)
freefunc(cmdp->param.func);
free(cmdp);
INT_ON;
}
/*
* Add a new command entry, replacing any existing command entry for
* the same name - except special builtins.
*/
static void
addcmdentry(char *name, struct cmdentry *entry)
{
struct tblentry *cmdp;
cmdp = cmdlookup(name, 1);
if (cmdp->cmdtype == CMDFUNCTION) {
freefunc(cmdp->param.func);
}
cmdp->cmdtype = entry->cmdtype;
cmdp->param = entry->u;
cmdp->rehash = 0;
}
static int FAST_FUNC
hashcmd(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
{
struct tblentry **pp;
struct tblentry *cmdp;
int c;
struct cmdentry entry;
char *name;
if (nextopt("r") != '\0') {
clearcmdentry(0);
return 0;
}
if (*argptr == NULL) {
for (pp = cmdtable; pp < &cmdtable[CMDTABLESIZE]; pp++) {
for (cmdp = *pp; cmdp; cmdp = cmdp->next) {
if (cmdp->cmdtype == CMDNORMAL)
printentry(cmdp);
}
}
return 0;
}
c = 0;
while ((name = *argptr) != NULL) {
cmdp = cmdlookup(name, 0);
if (cmdp != NULL
&& (cmdp->cmdtype == CMDNORMAL
|| (cmdp->cmdtype == CMDBUILTIN && builtinloc >= 0))
) {
delete_cmd_entry();
}
find_command(name, &entry, DO_ERR, pathval());
if (entry.cmdtype == CMDUNKNOWN)
c = 1;
argptr++;
}
return c;
}
/*
* Called when a cd is done. Marks all commands so the next time they
* are executed they will be rehashed.
*/
static void
hashcd(void)
{
struct tblentry **pp;
struct tblentry *cmdp;
for (pp = cmdtable; pp < &cmdtable[CMDTABLESIZE]; pp++) {
for (cmdp = *pp; cmdp; cmdp = cmdp->next) {
if (cmdp->cmdtype == CMDNORMAL
|| (cmdp->cmdtype == CMDBUILTIN
&& !IS_BUILTIN_REGULAR(cmdp->param.cmd)
&& builtinloc > 0)
) {
cmdp->rehash = 1;
}
}
}
}
/*
* Fix command hash table when PATH changed.
* Called before PATH is changed. The argument is the new value of PATH;
* pathval() still returns the old value at this point.
* Called with interrupts off.
*/
static void FAST_FUNC
changepath(const char *new)
{
const char *old;
int firstchange;
int idx;
int idx_bltin;
old = pathval();
firstchange = 9999; /* assume no change */
idx = 0;
idx_bltin = -1;
for (;;) {
if (*old != *new) {
firstchange = idx;
if ((*old == '\0' && *new == ':')
|| (*old == ':' && *new == '\0')
) {
firstchange++;
}
old = new; /* ignore subsequent differences */
}
if (*new == '\0')
break;
if (*new == '%' && idx_bltin < 0 && prefix(new + 1, "builtin"))
idx_bltin = idx;
if (*new == ':')
idx++;
new++;
old++;
}
if (builtinloc < 0 && idx_bltin >= 0)
builtinloc = idx_bltin; /* zap builtins */
if (builtinloc >= 0 && idx_bltin < 0)
firstchange = 0;
clearcmdentry(firstchange);
builtinloc = idx_bltin;
}
#define TEOF 0
#define TNL 1
#define TREDIR 2
#define TWORD 3
#define TSEMI 4
#define TBACKGND 5
#define TAND 6
#define TOR 7
#define TPIPE 8
#define TLP 9
#define TRP 10
#define TENDCASE 11
#define TENDBQUOTE 12
#define TNOT 13
#define TCASE 14
#define TDO 15
#define TDONE 16
#define TELIF 17
#define TELSE 18
#define TESAC 19
#define TFI 20
#define TFOR 21
#define TIF 22
#define TIN 23
#define TTHEN 24
#define TUNTIL 25
#define TWHILE 26
#define TBEGIN 27
#define TEND 28
typedef smallint token_id_t;
/* first char is indicating which tokens mark the end of a list */
static const char *const tokname_array[] = {
"\1end of file",
"\0newline",
"\0redirection",
"\0word",
"\0;",
"\0&",
"\0&&",
"\0||",
"\0|",
"\0(",
"\1)",
"\1;;",
"\1`",
#define KWDOFFSET 13
/* the following are keywords */
"\0!",
"\0case",
"\1do",
"\1done",
"\1elif",
"\1else",
"\1esac",
"\1fi",
"\0for",
"\0if",
"\0in",
"\1then",
"\0until",
"\0while",
"\0{",
"\1}",
};
/* Wrapper around strcmp for qsort/bsearch/... */
static int
pstrcmp(const void *a, const void *b)
{
return strcmp((char*) a, (*(char**) b) + 1);
}
static const char *const *
findkwd(const char *s)
{
return bsearch(s, tokname_array + KWDOFFSET,
ARRAY_SIZE(tokname_array) - KWDOFFSET,
sizeof(tokname_array[0]), pstrcmp);
}
/*
* Locate and print what a word is...
*/
static int
describe_command(char *command, int describe_command_verbose)
{
struct cmdentry entry;
struct tblentry *cmdp;
#if ENABLE_ASH_ALIAS
const struct alias *ap;
#endif
const char *path = pathval();
if (describe_command_verbose) {
out1str(command);
}
/* First look at the keywords */
if (findkwd(command)) {
out1str(describe_command_verbose ? " is a shell keyword" : command);
goto out;
}
#if ENABLE_ASH_ALIAS
/* Then look at the aliases */
ap = lookupalias(command, 0);
if (ap != NULL) {
if (!describe_command_verbose) {
out1str("alias ");
printalias(ap);
return 0;
}
out1fmt(" is an alias for %s", ap->val);
goto out;
}
#endif
/* Then check if it is a tracked alias */
cmdp = cmdlookup(command, 0);
if (cmdp != NULL) {
entry.cmdtype = cmdp->cmdtype;
entry.u = cmdp->param;
} else {
/* Finally use brute force */
find_command(command, &entry, DO_ABS, path);
}
switch (entry.cmdtype) {
case CMDNORMAL: {
int j = entry.u.index;
char *p;
if (j < 0) {
p = command;
} else {
do {
p = path_advance(&path, command);
stunalloc(p);
} while (--j >= 0);
}
if (describe_command_verbose) {
out1fmt(" is%s %s",
(cmdp ? " a tracked alias for" : nullstr), p
);
} else {
out1str(p);
}
break;
}
case CMDFUNCTION:
if (describe_command_verbose) {
out1str(" is a shell function");
} else {
out1str(command);
}
break;
case CMDBUILTIN:
if (describe_command_verbose) {
out1fmt(" is a %sshell builtin",
IS_BUILTIN_SPECIAL(entry.u.cmd) ?
"special " : nullstr
);
} else {
out1str(command);
}
break;
default:
if (describe_command_verbose) {
out1str(": not found\n");
}
return 127;
}
out:
out1str("\n");
return 0;
}
static int FAST_FUNC
typecmd(int argc UNUSED_PARAM, char **argv)
{
int i = 1;
int err = 0;
int verbose = 1;
/* type -p ... ? (we don't bother checking for 'p') */
if (argv[1] && argv[1][0] == '-') {
i++;
verbose = 0;
}
while (argv[i]) {
err |= describe_command(argv[i++], verbose);
}
return err;
}
#if ENABLE_ASH_CMDCMD
static int FAST_FUNC
commandcmd(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
{
int c;
enum {
VERIFY_BRIEF = 1,
VERIFY_VERBOSE = 2,
} verify = 0;
while ((c = nextopt("pvV")) != '\0')
if (c == 'V')
verify |= VERIFY_VERBOSE;
else if (c == 'v')
verify |= VERIFY_BRIEF;
#if DEBUG
else if (c != 'p')
abort();
#endif
/* Mimic bash: just "command -v" doesn't complain, it's a nop */
if (verify && (*argptr != NULL)) {
return describe_command(*argptr, verify - VERIFY_BRIEF);
}
return 0;
}
#endif
/* ============ eval.c */
static int funcblocksize; /* size of structures in function */
static int funcstringsize; /* size of strings in node */
static void *funcblock; /* block to allocate function from */
static char *funcstring; /* block to allocate strings from */
/* flags in argument to evaltree */
#define EV_EXIT 01 /* exit after evaluating tree */
#define EV_TESTED 02 /* exit status is checked; ignore -e flag */
#define EV_BACKCMD 04 /* command executing within back quotes */
static const uint8_t nodesize[N_NUMBER] = {
[NCMD ] = SHELL_ALIGN(sizeof(struct ncmd)),
[NPIPE ] = SHELL_ALIGN(sizeof(struct npipe)),
[NREDIR ] = SHELL_ALIGN(sizeof(struct nredir)),
[NBACKGND ] = SHELL_ALIGN(sizeof(struct nredir)),
[NSUBSHELL] = SHELL_ALIGN(sizeof(struct nredir)),
[NAND ] = SHELL_ALIGN(sizeof(struct nbinary)),
[NOR ] = SHELL_ALIGN(sizeof(struct nbinary)),
[NSEMI ] = SHELL_ALIGN(sizeof(struct nbinary)),
[NIF ] = SHELL_ALIGN(sizeof(struct nif)),
[NWHILE ] = SHELL_ALIGN(sizeof(struct nbinary)),
[NUNTIL ] = SHELL_ALIGN(sizeof(struct nbinary)),
[NFOR ] = SHELL_ALIGN(sizeof(struct nfor)),
[NCASE ] = SHELL_ALIGN(sizeof(struct ncase)),
[NCLIST ] = SHELL_ALIGN(sizeof(struct nclist)),
[NDEFUN ] = SHELL_ALIGN(sizeof(struct narg)),
[NARG ] = SHELL_ALIGN(sizeof(struct narg)),
[NTO ] = SHELL_ALIGN(sizeof(struct nfile)),
#if ENABLE_ASH_BASH_COMPAT
[NTO2 ] = SHELL_ALIGN(sizeof(struct nfile)),
#endif
[NCLOBBER ] = SHELL_ALIGN(sizeof(struct nfile)),
[NFROM ] = SHELL_ALIGN(sizeof(struct nfile)),
[NFROMTO ] = SHELL_ALIGN(sizeof(struct nfile)),
[NAPPEND ] = SHELL_ALIGN(sizeof(struct nfile)),
[NTOFD ] = SHELL_ALIGN(sizeof(struct ndup)),
[NFROMFD ] = SHELL_ALIGN(sizeof(struct ndup)),
[NHERE ] = SHELL_ALIGN(sizeof(struct nhere)),
[NXHERE ] = SHELL_ALIGN(sizeof(struct nhere)),
[NNOT ] = SHELL_ALIGN(sizeof(struct nnot)),
};
static void calcsize(union node *n);
static void
sizenodelist(struct nodelist *lp)
{
while (lp) {
funcblocksize += SHELL_ALIGN(sizeof(struct nodelist));
calcsize(lp->n);
lp = lp->next;
}
}
static void
calcsize(union node *n)
{
if (n == NULL)
return;
funcblocksize += nodesize[n->type];
switch (n->type) {
case NCMD:
calcsize(n->ncmd.redirect);
calcsize(n->ncmd.args);
calcsize(n->ncmd.assign);
break;
case NPIPE:
sizenodelist(n->npipe.cmdlist);
break;
case NREDIR:
case NBACKGND:
case NSUBSHELL:
calcsize(n->nredir.redirect);
calcsize(n->nredir.n);
break;
case NAND:
case NOR:
case NSEMI:
case NWHILE:
case NUNTIL:
calcsize(n->nbinary.ch2);
calcsize(n->nbinary.ch1);
break;
case NIF:
calcsize(n->nif.elsepart);
calcsize(n->nif.ifpart);
calcsize(n->nif.test);
break;
case NFOR:
funcstringsize += strlen(n->nfor.var) + 1;
calcsize(n->nfor.body);
calcsize(n->nfor.args);
break;
case NCASE:
calcsize(n->ncase.cases);
calcsize(n->ncase.expr);
break;
case NCLIST:
calcsize(n->nclist.body);
calcsize(n->nclist.pattern);
calcsize(n->nclist.next);
break;
case NDEFUN:
case NARG:
sizenodelist(n->narg.backquote);
funcstringsize += strlen(n->narg.text) + 1;
calcsize(n->narg.next);
break;
case NTO:
#if ENABLE_ASH_BASH_COMPAT
case NTO2:
#endif
case NCLOBBER:
case NFROM:
case NFROMTO:
case NAPPEND:
calcsize(n->nfile.fname);
calcsize(n->nfile.next);
break;
case NTOFD:
case NFROMFD:
calcsize(n->ndup.vname);
calcsize(n->ndup.next);
break;
case NHERE:
case NXHERE:
calcsize(n->nhere.doc);
calcsize(n->nhere.next);
break;
case NNOT:
calcsize(n->nnot.com);
break;
};
}
static char *
nodeckstrdup(char *s)
{
char *rtn = funcstring;
strcpy(funcstring, s);
funcstring += strlen(s) + 1;
return rtn;
}
static union node *copynode(union node *);
static struct nodelist *
copynodelist(struct nodelist *lp)
{
struct nodelist *start;
struct nodelist **lpp;
lpp = &start;
while (lp) {
*lpp = funcblock;
funcblock = (char *) funcblock + SHELL_ALIGN(sizeof(struct nodelist));
(*lpp)->n = copynode(lp->n);
lp = lp->next;
lpp = &(*lpp)->next;
}
*lpp = NULL;
return start;
}
static union node *
copynode(union node *n)
{
union node *new;
if (n == NULL)
return NULL;
new = funcblock;
funcblock = (char *) funcblock + nodesize[n->type];
switch (n->type) {
case NCMD:
new->ncmd.redirect = copynode(n->ncmd.redirect);
new->ncmd.args = copynode(n->ncmd.args);
new->ncmd.assign = copynode(n->ncmd.assign);
break;
case NPIPE:
new->npipe.cmdlist = copynodelist(n->npipe.cmdlist);
new->npipe.pipe_backgnd = n->npipe.pipe_backgnd;
break;
case NREDIR:
case NBACKGND:
case NSUBSHELL:
new->nredir.redirect = copynode(n->nredir.redirect);
new->nredir.n = copynode(n->nredir.n);
break;
case NAND:
case NOR:
case NSEMI:
case NWHILE:
case NUNTIL:
new->nbinary.ch2 = copynode(n->nbinary.ch2);
new->nbinary.ch1 = copynode(n->nbinary.ch1);
break;
case NIF:
new->nif.elsepart = copynode(n->nif.elsepart);
new->nif.ifpart = copynode(n->nif.ifpart);
new->nif.test = copynode(n->nif.test);
break;
case NFOR:
new->nfor.var = nodeckstrdup(n->nfor.var);
new->nfor.body = copynode(n->nfor.body);
new->nfor.args = copynode(n->nfor.args);
break;
case NCASE:
new->ncase.cases = copynode(n->ncase.cases);
new->ncase.expr = copynode(n->ncase.expr);
break;
case NCLIST:
new->nclist.body = copynode(n->nclist.body);
new->nclist.pattern = copynode(n->nclist.pattern);
new->nclist.next = copynode(n->nclist.next);
break;
case NDEFUN:
case NARG:
new->narg.backquote = copynodelist(n->narg.backquote);
new->narg.text = nodeckstrdup(n->narg.text);
new->narg.next = copynode(n->narg.next);
break;
case NTO:
#if ENABLE_ASH_BASH_COMPAT
case NTO2:
#endif
case NCLOBBER:
case NFROM:
case NFROMTO:
case NAPPEND:
new->nfile.fname = copynode(n->nfile.fname);
new->nfile.fd = n->nfile.fd;
new->nfile.next = copynode(n->nfile.next);
break;
case NTOFD:
case NFROMFD:
new->ndup.vname = copynode(n->ndup.vname);
new->ndup.dupfd = n->ndup.dupfd;
new->ndup.fd = n->ndup.fd;
new->ndup.next = copynode(n->ndup.next);
break;
case NHERE:
case NXHERE:
new->nhere.doc = copynode(n->nhere.doc);
new->nhere.fd = n->nhere.fd;
new->nhere.next = copynode(n->nhere.next);
break;
case NNOT:
new->nnot.com = copynode(n->nnot.com);
break;
};
new->type = n->type;
return new;
}
/*
* Make a copy of a parse tree.
*/
static struct funcnode *
copyfunc(union node *n)
{
struct funcnode *f;
size_t blocksize;
funcblocksize = offsetof(struct funcnode, n);
funcstringsize = 0;
calcsize(n);
blocksize = funcblocksize;
f = ckmalloc(blocksize + funcstringsize);
funcblock = (char *) f + offsetof(struct funcnode, n);
funcstring = (char *) f + blocksize;
copynode(n);
f->count = 0;
return f;
}
/*
* Define a shell function.
*/
static void
defun(char *name, union node *func)
{
struct cmdentry entry;
INT_OFF;
entry.cmdtype = CMDFUNCTION;
entry.u.func = copyfunc(func);
addcmdentry(name, &entry);
INT_ON;
}
/* Reasons for skipping commands (see comment on breakcmd routine) */
#define SKIPBREAK (1 << 0)
#define SKIPCONT (1 << 1)
#define SKIPFUNC (1 << 2)
#define SKIPFILE (1 << 3)
#define SKIPEVAL (1 << 4)
static smallint evalskip; /* set to SKIPxxx if we are skipping commands */
static int skipcount; /* number of levels to skip */
static int funcnest; /* depth of function calls */
static int loopnest; /* current loop nesting level */
/* Forward decl way out to parsing code - dotrap needs it */
static int evalstring(char *s, int mask);
/* Called to execute a trap.
* Single callsite - at the end of evaltree().
* If we return non-zero, exaltree raises EXEXIT exception.
*
* Perhaps we should avoid entering new trap handlers
* while we are executing a trap handler. [is it a TODO?]
*/
static int
dotrap(void)
{
uint8_t *g;
int sig;
uint8_t savestatus;
savestatus = exitstatus;
pending_sig = 0;
xbarrier();
TRACE(("dotrap entered\n"));
for (sig = 1, g = gotsig; sig < NSIG; sig++, g++) {
int want_exexit;
char *t;
if (*g == 0)
continue;
t = trap[sig];
/* non-trapped SIGINT is handled separately by raise_interrupt,
* don't upset it by resetting gotsig[SIGINT-1] */
if (sig == SIGINT && !t)
continue;
TRACE(("sig %d is active, will run handler '%s'\n", sig, t));
*g = 0;
if (!t)
continue;
want_exexit = evalstring(t, SKIPEVAL);
exitstatus = savestatus;
if (want_exexit) {
TRACE(("dotrap returns %d\n", want_exexit));
return want_exexit;
}
}
TRACE(("dotrap returns 0\n"));
return 0;
}
/* forward declarations - evaluation is fairly recursive business... */
static void evalloop(union node *, int);
static void evalfor(union node *, int);
static void evalcase(union node *, int);
static void evalsubshell(union node *, int);
static void expredir(union node *);
static void evalpipe(union node *, int);
static void evalcommand(union node *, int);
static int evalbltin(const struct builtincmd *, int, char **);
static void prehash(union node *);
/*
* Evaluate a parse tree. The value is left in the global variable
* exitstatus.
*/
static void
evaltree(union node *n, int flags)
{
struct jmploc *volatile savehandler = exception_handler;
struct jmploc jmploc;
int checkexit = 0;
void (*evalfn)(union node *, int);
int status;
int int_level;
SAVE_INT(int_level);
if (n == NULL) {
TRACE(("evaltree(NULL) called\n"));
goto out1;
}
TRACE(("evaltree(%p: %d, %d) called\n", n, n->type, flags));
exception_handler = &jmploc;
{
int err = setjmp(jmploc.loc);
if (err) {
/* if it was a signal, check for trap handlers */
if (exception_type == EXSIG) {
TRACE(("exception %d (EXSIG) in evaltree, err=%d\n",
exception_type, err));
goto out;
}
/* continue on the way out */
TRACE(("exception %d in evaltree, propagating err=%d\n",
exception_type, err));
exception_handler = savehandler;
longjmp(exception_handler->loc, err);
}
}
switch (n->type) {
default:
#if DEBUG
out1fmt("Node type = %d\n", n->type);
fflush_all();
break;
#endif
case NNOT:
evaltree(n->nnot.com, EV_TESTED);
status = !exitstatus;
goto setstatus;
case NREDIR:
expredir(n->nredir.redirect);
status = redirectsafe(n->nredir.redirect, REDIR_PUSH);
if (!status) {
evaltree(n->nredir.n, flags & EV_TESTED);
status = exitstatus;
}
popredir(/*drop:*/ 0, /*restore:*/ 0 /* not sure */);
goto setstatus;
case NCMD:
evalfn = evalcommand;
checkexit:
if (eflag && !(flags & EV_TESTED))
checkexit = ~0;
goto calleval;
case NFOR:
evalfn = evalfor;
goto calleval;
case NWHILE:
case NUNTIL:
evalfn = evalloop;
goto calleval;
case NSUBSHELL:
case NBACKGND:
evalfn = evalsubshell;
goto calleval;
case NPIPE:
evalfn = evalpipe;
goto checkexit;
case NCASE:
evalfn = evalcase;
goto calleval;
case NAND:
case NOR:
case NSEMI: {
#if NAND + 1 != NOR
#error NAND + 1 != NOR
#endif
#if NOR + 1 != NSEMI
#error NOR + 1 != NSEMI
#endif
unsigned is_or = n->type - NAND;
evaltree(
n->nbinary.ch1,
(flags | ((is_or >> 1) - 1)) & EV_TESTED
);
if (!exitstatus == is_or)
break;
if (!evalskip) {
n = n->nbinary.ch2;
evaln:
evalfn = evaltree;
calleval:
evalfn(n, flags);
break;
}
break;
}
case NIF:
evaltree(n->nif.test, EV_TESTED);
if (evalskip)
break;
if (exitstatus == 0) {
n = n->nif.ifpart;
goto evaln;
}
if (n->nif.elsepart) {
n = n->nif.elsepart;
goto evaln;
}
goto success;
case NDEFUN:
defun(n->narg.text, n->narg.next);
success:
status = 0;
setstatus:
exitstatus = status;
break;
}
out:
exception_handler = savehandler;
out1:
if (checkexit & exitstatus)
evalskip |= SKIPEVAL;
else if (pending_sig && dotrap())
goto exexit;
if (flags & EV_EXIT) {
exexit:
raise_exception(EXEXIT);
}
RESTORE_INT(int_level);
TRACE(("leaving evaltree (no interrupts)\n"));
}
#if !defined(__alpha__) || (defined(__GNUC__) && __GNUC__ >= 3)
static
#endif
void evaltreenr(union node *, int) __attribute__ ((alias("evaltree"),__noreturn__));
static void
evalloop(union node *n, int flags)
{
int status;
loopnest++;
status = 0;
flags &= EV_TESTED;
for (;;) {
int i;
evaltree(n->nbinary.ch1, EV_TESTED);
if (evalskip) {
skipping:
if (evalskip == SKIPCONT && --skipcount <= 0) {
evalskip = 0;
continue;
}
if (evalskip == SKIPBREAK && --skipcount <= 0)
evalskip = 0;
break;
}
i = exitstatus;
if (n->type != NWHILE)
i = !i;
if (i != 0)
break;
evaltree(n->nbinary.ch2, flags);
status = exitstatus;
if (evalskip)
goto skipping;
}
loopnest--;
exitstatus = status;
}
static void
evalfor(union node *n, int flags)
{
struct arglist arglist;
union node *argp;
struct strlist *sp;
struct stackmark smark;
setstackmark(&smark);
arglist.list = NULL;
arglist.lastp = &arglist.list;
for (argp = n->nfor.args; argp; argp = argp->narg.next) {
expandarg(argp, &arglist, EXP_FULL | EXP_TILDE | EXP_RECORD);
/* XXX */
if (evalskip)
goto out;
}
*arglist.lastp = NULL;
exitstatus = 0;
loopnest++;
flags &= EV_TESTED;
for (sp = arglist.list; sp; sp = sp->next) {
setvar(n->nfor.var, sp->text, 0);
evaltree(n->nfor.body, flags);
if (evalskip) {
if (evalskip == SKIPCONT && --skipcount <= 0) {
evalskip = 0;
continue;
}
if (evalskip == SKIPBREAK && --skipcount <= 0)
evalskip = 0;
break;
}
}
loopnest--;
out:
popstackmark(&smark);
}
static void
evalcase(union node *n, int flags)
{
union node *cp;
union node *patp;
struct arglist arglist;
struct stackmark smark;
setstackmark(&smark);
arglist.list = NULL;
arglist.lastp = &arglist.list;
expandarg(n->ncase.expr, &arglist, EXP_TILDE);
exitstatus = 0;
for (cp = n->ncase.cases; cp && evalskip == 0; cp = cp->nclist.next) {
for (patp = cp->nclist.pattern; patp; patp = patp->narg.next) {
if (casematch(patp, arglist.list->text)) {
if (evalskip == 0) {
evaltree(cp->nclist.body, flags);
}
goto out;
}
}
}
out:
popstackmark(&smark);
}
/*
* Kick off a subshell to evaluate a tree.
*/
static void
evalsubshell(union node *n, int flags)
{
struct job *jp;
int backgnd = (n->type == NBACKGND);
int status;
expredir(n->nredir.redirect);
if (!backgnd && (flags & EV_EXIT) && !may_have_traps)
goto nofork;
INT_OFF;
jp = makejob(/*n,*/ 1);
if (forkshell(jp, n, backgnd) == 0) {
/* child */
INT_ON;
flags |= EV_EXIT;
if (backgnd)
flags &= ~EV_TESTED;
nofork:
redirect(n->nredir.redirect, 0);
evaltreenr(n->nredir.n, flags);
/* never returns */
}
status = 0;
if (!backgnd)
status = waitforjob(jp);
exitstatus = status;
INT_ON;
}
/*
* Compute the names of the files in a redirection list.
*/
static void fixredir(union node *, const char *, int);
static void
expredir(union node *n)
{
union node *redir;
for (redir = n; redir; redir = redir->nfile.next) {
struct arglist fn;
fn.list = NULL;
fn.lastp = &fn.list;
switch (redir->type) {
case NFROMTO:
case NFROM:
case NTO:
#if ENABLE_ASH_BASH_COMPAT
case NTO2:
#endif
case NCLOBBER:
case NAPPEND:
expandarg(redir->nfile.fname, &fn, EXP_TILDE | EXP_REDIR);
#if ENABLE_ASH_BASH_COMPAT
store_expfname:
#endif
redir->nfile.expfname = fn.list->text;
break;
case NFROMFD:
case NTOFD: /* >& */
if (redir->ndup.vname) {
expandarg(redir->ndup.vname, &fn, EXP_FULL | EXP_TILDE);
if (fn.list == NULL)
ash_msg_and_raise_error("redir error");
#if ENABLE_ASH_BASH_COMPAT
//FIXME: we used expandarg with different args!
if (!isdigit_str9(fn.list->text)) {
/* >&file, not >&fd */
if (redir->nfile.fd != 1) /* 123>&file - BAD */
ash_msg_and_raise_error("redir error");
redir->type = NTO2;
goto store_expfname;
}
#endif
fixredir(redir, fn.list->text, 1);
}
break;
}
}
}
/*
* Evaluate a pipeline. All the processes in the pipeline are children
* of the process creating the pipeline. (This differs from some versions
* of the shell, which make the last process in a pipeline the parent
* of all the rest.)
*/
static void
evalpipe(union node *n, int flags)
{
struct job *jp;
struct nodelist *lp;
int pipelen;
int prevfd;
int pip[2];
TRACE(("evalpipe(0x%lx) called\n", (long)n));
pipelen = 0;
for (lp = n->npipe.cmdlist; lp; lp = lp->next)
pipelen++;
flags |= EV_EXIT;
INT_OFF;
jp = makejob(/*n,*/ pipelen);
prevfd = -1;
for (lp = n->npipe.cmdlist; lp; lp = lp->next) {
prehash(lp->n);
pip[1] = -1;
if (lp->next) {
if (pipe(pip) < 0) {
close(prevfd);
ash_msg_and_raise_error("pipe call failed");
}
}
if (forkshell(jp, lp->n, n->npipe.pipe_backgnd) == 0) {
INT_ON;
if (pip[1] >= 0) {
close(pip[0]);
}
if (prevfd > 0) {
dup2(prevfd, 0);
close(prevfd);
}
if (pip[1] > 1) {
dup2(pip[1], 1);
close(pip[1]);
}
evaltreenr(lp->n, flags);
/* never returns */
}
if (prevfd >= 0)
close(prevfd);
prevfd = pip[0];
/* Don't want to trigger debugging */
if (pip[1] != -1)
close(pip[1]);
}
if (n->npipe.pipe_backgnd == 0) {
exitstatus = waitforjob(jp);
TRACE(("evalpipe: job done exit status %d\n", exitstatus));
}
INT_ON;
}
/*
* Controls whether the shell is interactive or not.
*/
static void
setinteractive(int on)
{
static smallint is_interactive;
if (++on == is_interactive)
return;
is_interactive = on;
setsignal(SIGINT);
setsignal(SIGQUIT);
setsignal(SIGTERM);
#if !ENABLE_FEATURE_SH_EXTRA_QUIET
if (is_interactive > 1) {
/* Looks like they want an interactive shell */
static smallint did_banner;
if (!did_banner) {
/* note: ash and hush share this string */
out1fmt("\n\n%s %s\n"
"Enter 'help' for a list of built-in commands."
"\n\n",
bb_banner,
"built-in shell (ash)"
);
did_banner = 1;
}
}
#endif
}
static void
optschanged(void)
{
#if DEBUG
opentrace();
#endif
setinteractive(iflag);
setjobctl(mflag);
#if ENABLE_FEATURE_EDITING_VI
if (viflag)
line_input_state->flags |= VI_MODE;
else
line_input_state->flags &= ~VI_MODE;
#else
viflag = 0; /* forcibly keep the option off */
#endif
}
static struct localvar *localvars;
/*
* Called after a function returns.
* Interrupts must be off.
*/
static void
poplocalvars(void)
{
struct localvar *lvp;
struct var *vp;
while ((lvp = localvars) != NULL) {
localvars = lvp->next;
vp = lvp->vp;
TRACE(("poplocalvar %s\n", vp ? vp->text : "-"));
if (vp == NULL) { /* $- saved */
memcpy(optlist, lvp->text, sizeof(optlist));
free((char*)lvp->text);
optschanged();
} else if ((lvp->flags & (VUNSET|VSTRFIXED)) == VUNSET) {
unsetvar(vp->text);
} else {
if (vp->func)
(*vp->func)(strchrnul(lvp->text, '=') + 1);
if ((vp->flags & (VTEXTFIXED|VSTACK)) == 0)
free((char*)vp->text);
vp->flags = lvp->flags;
vp->text = lvp->text;
}
free(lvp);
}
}
static int
evalfun(struct funcnode *func, int argc, char **argv, int flags)
{
volatile struct shparam saveparam;
struct localvar *volatile savelocalvars;
struct jmploc *volatile savehandler;
struct jmploc jmploc;
int e;
saveparam = shellparam;
savelocalvars = localvars;
e = setjmp(jmploc.loc);
if (e) {
goto funcdone;
}
INT_OFF;
savehandler = exception_handler;
exception_handler = &jmploc;
localvars = NULL;
shellparam.malloced = 0;
func->count++;
funcnest++;
INT_ON;
shellparam.nparam = argc - 1;
shellparam.p = argv + 1;
#if ENABLE_ASH_GETOPTS
shellparam.optind = 1;
shellparam.optoff = -1;
#endif
evaltree(&func->n, flags & EV_TESTED);
funcdone:
INT_OFF;
funcnest--;
freefunc(func);
poplocalvars();
localvars = savelocalvars;
freeparam(&shellparam);
shellparam = saveparam;
exception_handler = savehandler;
INT_ON;
evalskip &= ~SKIPFUNC;
return e;
}
#if ENABLE_ASH_CMDCMD
static char **
parse_command_args(char **argv, const char **path)
{
char *cp, c;
for (;;) {
cp = *++argv;
if (!cp)
return 0;
if (*cp++ != '-')
break;
c = *cp++;
if (!c)
break;
if (c == '-' && !*cp) {
argv++;
break;
}
do {
switch (c) {
case 'p':
*path = bb_default_path;
break;
default:
/* run 'typecmd' for other options */
return 0;
}
c = *cp++;
} while (c);
}
return argv;
}
#endif
/*
* Make a variable a local variable. When a variable is made local, it's
* value and flags are saved in a localvar structure. The saved values
* will be restored when the shell function returns. We handle the name
* "-" as a special case.
*/
static void
mklocal(char *name)
{
struct localvar *lvp;
struct var **vpp;
struct var *vp;
INT_OFF;
lvp = ckzalloc(sizeof(struct localvar));
if (LONE_DASH(name)) {
char *p;
p = ckmalloc(sizeof(optlist));
lvp->text = memcpy(p, optlist, sizeof(optlist));
vp = NULL;
} else {
char *eq;
vpp = hashvar(name);
vp = *findvar(vpp, name);
eq = strchr(name, '=');
if (vp == NULL) {
if (eq)
setvareq(name, VSTRFIXED);
else
setvar(name, NULL, VSTRFIXED);
vp = *vpp; /* the new variable */
lvp->flags = VUNSET;
} else {
lvp->text = vp->text;
lvp->flags = vp->flags;
vp->flags |= VSTRFIXED|VTEXTFIXED;
if (eq)
setvareq(name, 0);
}
}
lvp->vp = vp;
lvp->next = localvars;
localvars = lvp;
INT_ON;
}
/*
* The "local" command.
*/
static int FAST_FUNC
localcmd(int argc UNUSED_PARAM, char **argv)
{
char *name;
argv = argptr;
while ((name = *argv++) != NULL) {
mklocal(name);
}
return 0;
}
static int FAST_FUNC
falsecmd(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
{
return 1;
}
static int FAST_FUNC
truecmd(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
{
return 0;
}
static int FAST_FUNC
execcmd(int argc UNUSED_PARAM, char **argv)
{
if (argv[1]) {
iflag = 0; /* exit on error */
mflag = 0;
optschanged();
shellexec(argv + 1, pathval(), 0);
}
return 0;
}
/*
* The return command.
*/
static int FAST_FUNC
returncmd(int argc UNUSED_PARAM, char **argv)
{
/*
* If called outside a function, do what ksh does;
* skip the rest of the file.
*/
evalskip = funcnest ? SKIPFUNC : SKIPFILE;
return argv[1] ? number(argv[1]) : exitstatus;
}
/* Forward declarations for builtintab[] */
static int breakcmd(int, char **) FAST_FUNC;
static int dotcmd(int, char **) FAST_FUNC;
static int evalcmd(int, char **) FAST_FUNC;
static int exitcmd(int, char **) FAST_FUNC;
static int exportcmd(int, char **) FAST_FUNC;
#if ENABLE_ASH_GETOPTS
static int getoptscmd(int, char **) FAST_FUNC;
#endif
#if !ENABLE_FEATURE_SH_EXTRA_QUIET
static int helpcmd(int, char **) FAST_FUNC;
#endif
#if ENABLE_SH_MATH_SUPPORT
static int letcmd(int, char **) FAST_FUNC;
#endif
static int readcmd(int, char **) FAST_FUNC;
static int setcmd(int, char **) FAST_FUNC;
static int shiftcmd(int, char **) FAST_FUNC;
static int timescmd(int, char **) FAST_FUNC;
static int trapcmd(int, char **) FAST_FUNC;
static int umaskcmd(int, char **) FAST_FUNC;
static int unsetcmd(int, char **) FAST_FUNC;
static int ulimitcmd(int, char **) FAST_FUNC;
#define BUILTIN_NOSPEC "0"
#define BUILTIN_SPECIAL "1"
#define BUILTIN_REGULAR "2"
#define BUILTIN_SPEC_REG "3"
#define BUILTIN_ASSIGN "4"
#define BUILTIN_SPEC_ASSG "5"
#define BUILTIN_REG_ASSG "6"
#define BUILTIN_SPEC_REG_ASSG "7"
/* Stubs for calling non-FAST_FUNC's */
#if ENABLE_ASH_BUILTIN_ECHO
static int FAST_FUNC echocmd(int argc, char **argv) { return echo_main(argc, argv); }
#endif
#if ENABLE_ASH_BUILTIN_PRINTF
static int FAST_FUNC printfcmd(int argc, char **argv) { return printf_main(argc, argv); }
#endif
#if ENABLE_ASH_BUILTIN_TEST
static int FAST_FUNC testcmd(int argc, char **argv) { return test_main(argc, argv); }
#endif
/* Keep these in proper order since it is searched via bsearch() */
static const struct builtincmd builtintab[] = {
{ BUILTIN_SPEC_REG "." , dotcmd },
{ BUILTIN_SPEC_REG ":" , truecmd },
#if ENABLE_ASH_BUILTIN_TEST
{ BUILTIN_REGULAR "[" , testcmd },
#if ENABLE_ASH_BASH_COMPAT
{ BUILTIN_REGULAR "[[" , testcmd },
#endif
#endif
#if ENABLE_ASH_ALIAS
{ BUILTIN_REG_ASSG "alias" , aliascmd },
#endif
#if JOBS
{ BUILTIN_REGULAR "bg" , fg_bgcmd },
#endif
{ BUILTIN_SPEC_REG "break" , breakcmd },
{ BUILTIN_REGULAR "cd" , cdcmd },
{ BUILTIN_NOSPEC "chdir" , cdcmd },
#if ENABLE_ASH_CMDCMD
{ BUILTIN_REGULAR "command" , commandcmd },
#endif
{ BUILTIN_SPEC_REG "continue", breakcmd },
#if ENABLE_ASH_BUILTIN_ECHO
{ BUILTIN_REGULAR "echo" , echocmd },
#endif
{ BUILTIN_SPEC_REG "eval" , evalcmd },
{ BUILTIN_SPEC_REG "exec" , execcmd },
{ BUILTIN_SPEC_REG "exit" , exitcmd },
{ BUILTIN_SPEC_REG_ASSG "export" , exportcmd },
{ BUILTIN_REGULAR "false" , falsecmd },
#if JOBS
{ BUILTIN_REGULAR "fg" , fg_bgcmd },
#endif
#if ENABLE_ASH_GETOPTS
{ BUILTIN_REGULAR "getopts" , getoptscmd },
#endif
{ BUILTIN_NOSPEC "hash" , hashcmd },
#if !ENABLE_FEATURE_SH_EXTRA_QUIET
{ BUILTIN_NOSPEC "help" , helpcmd },
#endif
#if JOBS
{ BUILTIN_REGULAR "jobs" , jobscmd },
{ BUILTIN_REGULAR "kill" , killcmd },
#endif
#if ENABLE_SH_MATH_SUPPORT
{ BUILTIN_NOSPEC "let" , letcmd },
#endif
{ BUILTIN_ASSIGN "local" , localcmd },
#if ENABLE_ASH_BUILTIN_PRINTF
{ BUILTIN_REGULAR "printf" , printfcmd },
#endif
{ BUILTIN_NOSPEC "pwd" , pwdcmd },
{ BUILTIN_REGULAR "read" , readcmd },
{ BUILTIN_SPEC_REG_ASSG "readonly", exportcmd },
{ BUILTIN_SPEC_REG "return" , returncmd },
{ BUILTIN_SPEC_REG "set" , setcmd },
{ BUILTIN_SPEC_REG "shift" , shiftcmd },
#if ENABLE_ASH_BASH_COMPAT
{ BUILTIN_SPEC_REG "source" , dotcmd },
#endif
#if ENABLE_ASH_BUILTIN_TEST
{ BUILTIN_REGULAR "test" , testcmd },
#endif
{ BUILTIN_SPEC_REG "times" , timescmd },
{ BUILTIN_SPEC_REG "trap" , trapcmd },
{ BUILTIN_REGULAR "true" , truecmd },
{ BUILTIN_NOSPEC "type" , typecmd },
{ BUILTIN_NOSPEC "ulimit" , ulimitcmd },
{ BUILTIN_REGULAR "umask" , umaskcmd },
#if ENABLE_ASH_ALIAS
{ BUILTIN_REGULAR "unalias" , unaliascmd },
#endif
{ BUILTIN_SPEC_REG "unset" , unsetcmd },
{ BUILTIN_REGULAR "wait" , waitcmd },
};
/* Should match the above table! */
#define COMMANDCMD (builtintab + \
2 + \
1 * ENABLE_ASH_BUILTIN_TEST + \
1 * ENABLE_ASH_BUILTIN_TEST * ENABLE_ASH_BASH_COMPAT + \
1 * ENABLE_ASH_ALIAS + \
1 * ENABLE_ASH_JOB_CONTROL + \
3)
#define EXECCMD (builtintab + \
2 + \
1 * ENABLE_ASH_BUILTIN_TEST + \
1 * ENABLE_ASH_BUILTIN_TEST * ENABLE_ASH_BASH_COMPAT + \
1 * ENABLE_ASH_ALIAS + \
1 * ENABLE_ASH_JOB_CONTROL + \
3 + \
1 * ENABLE_ASH_CMDCMD + \
1 + \
ENABLE_ASH_BUILTIN_ECHO + \
1)
/*
* Search the table of builtin commands.
*/
static struct builtincmd *
find_builtin(const char *name)
{
struct builtincmd *bp;
bp = bsearch(
name, builtintab, ARRAY_SIZE(builtintab), sizeof(builtintab[0]),
pstrcmp
);
return bp;
}
/*
* Execute a simple command.
*/
static int
isassignment(const char *p)
{
const char *q = endofname(p);
if (p == q)
return 0;
return *q == '=';
}
static int FAST_FUNC
bltincmd(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
{
/* Preserve exitstatus of a previous possible redirection
* as POSIX mandates */
return back_exitstatus;
}
static void
evalcommand(union node *cmd, int flags)
{
static const struct builtincmd null_bltin = {
"\0\0", bltincmd /* why three NULs? */
};
struct stackmark smark;
union node *argp;
struct arglist arglist;
struct arglist varlist;
char **argv;
int argc;
const struct strlist *sp;
struct cmdentry cmdentry;
struct job *jp;
char *lastarg;
const char *path;
int spclbltin;
int status;
char **nargv;
struct builtincmd *bcmd;
smallint cmd_is_exec;
smallint pseudovarflag = 0;
/* First expand the arguments. */
TRACE(("evalcommand(0x%lx, %d) called\n", (long)cmd, flags));
setstackmark(&smark);
back_exitstatus = 0;
cmdentry.cmdtype = CMDBUILTIN;
cmdentry.u.cmd = &null_bltin;
varlist.lastp = &varlist.list;
*varlist.lastp = NULL;
arglist.lastp = &arglist.list;
*arglist.lastp = NULL;
argc = 0;
if (cmd->ncmd.args) {
bcmd = find_builtin(cmd->ncmd.args->narg.text);
pseudovarflag = bcmd && IS_BUILTIN_ASSIGN(bcmd);
}
for (argp = cmd->ncmd.args; argp; argp = argp->narg.next) {
struct strlist **spp;
spp = arglist.lastp;
if (pseudovarflag && isassignment(argp->narg.text))
expandarg(argp, &arglist, EXP_VARTILDE);
else
expandarg(argp, &arglist, EXP_FULL | EXP_TILDE);
for (sp = *spp; sp; sp = sp->next)
argc++;
}
argv = nargv = stalloc(sizeof(char *) * (argc + 1));
for (sp = arglist.list; sp; sp = sp->next) {
TRACE(("evalcommand arg: %s\n", sp->text));
*nargv++ = sp->text;
}
*nargv = NULL;
lastarg = NULL;
if (iflag && funcnest == 0 && argc > 0)
lastarg = nargv[-1];
preverrout_fd = 2;
expredir(cmd->ncmd.redirect);
status = redirectsafe(cmd->ncmd.redirect, REDIR_PUSH | REDIR_SAVEFD2);
path = vpath.text;
for (argp = cmd->ncmd.assign; argp; argp = argp->narg.next) {
struct strlist **spp;
char *p;
spp = varlist.lastp;
expandarg(argp, &varlist, EXP_VARTILDE);
/*
* Modify the command lookup path, if a PATH= assignment
* is present
*/
p = (*spp)->text;
if (varequal(p, path))
path = p;
}
/* Print the command if xflag is set. */
if (xflag) {
int n;
const char *p = " %s";
p++;
fdprintf(preverrout_fd, p, expandstr(ps4val()));
sp = varlist.list;
for (n = 0; n < 2; n++) {
while (sp) {
fdprintf(preverrout_fd, p, sp->text);
sp = sp->next;
if (*p == '%') {
p--;
}
}
sp = arglist.list;
}
safe_write(preverrout_fd, "\n", 1);
}
cmd_is_exec = 0;
spclbltin = -1;
/* Now locate the command. */
if (argc) {
const char *oldpath;
int cmd_flag = DO_ERR;
path += 5;
oldpath = path;
for (;;) {
find_command(argv[0], &cmdentry, cmd_flag, path);
if (cmdentry.cmdtype == CMDUNKNOWN) {
flush_stdout_stderr();
status = 127;
goto bail;
}
/* implement bltin and command here */
if (cmdentry.cmdtype != CMDBUILTIN)
break;
if (spclbltin < 0)
spclbltin = IS_BUILTIN_SPECIAL(cmdentry.u.cmd);
if (cmdentry.u.cmd == EXECCMD)
cmd_is_exec = 1;
#if ENABLE_ASH_CMDCMD
if (cmdentry.u.cmd == COMMANDCMD) {
path = oldpath;
nargv = parse_command_args(argv, &path);
if (!nargv)
break;
argc -= nargv - argv;
argv = nargv;
cmd_flag |= DO_NOFUNC;
} else
#endif
break;
}
}
if (status) {
/* We have a redirection error. */
if (spclbltin > 0)
raise_exception(EXERROR);
bail:
exitstatus = status;
goto out;
}
/* Execute the command. */
switch (cmdentry.cmdtype) {
default: {
#if ENABLE_FEATURE_SH_NOFORK
/* (1) BUG: if variables are set, we need to fork, or save/restore them
* around run_nofork_applet() call.
* (2) Should this check also be done in forkshell()?
* (perhaps it should, so that "VAR=VAL nofork" at least avoids exec...)
*/
/* find_command() encodes applet_no as (-2 - applet_no) */
int applet_no = (- cmdentry.u.index - 2);
if (applet_no >= 0 && APPLET_IS_NOFORK(applet_no)) {
listsetvar(varlist.list, VEXPORT|VSTACK);
/* run <applet>_main() */
exitstatus = run_nofork_applet(applet_no, argv);
break;
}
#endif
/* Can we avoid forking off? For example, very last command
* in a script or a subshell does not need forking,
* we can just exec it.
*/
if (!(flags & EV_EXIT) || may_have_traps) {
/* No, forking off a child is necessary */
INT_OFF;
jp = makejob(/*cmd,*/ 1);
if (forkshell(jp, cmd, FORK_FG) != 0) {
/* parent */
exitstatus = waitforjob(jp);
INT_ON;
TRACE(("forked child exited with %d\n", exitstatus));
break;
}
/* child */
FORCE_INT_ON;
/* fall through to exec'ing external program */
}
listsetvar(varlist.list, VEXPORT|VSTACK);
shellexec(argv, path, cmdentry.u.index);
/* NOTREACHED */
} /* default */
case CMDBUILTIN:
cmdenviron = varlist.list;
if (cmdenviron) {
struct strlist *list = cmdenviron;
int i = VNOSET;
if (spclbltin > 0 || argc == 0) {
i = 0;
if (cmd_is_exec && argc > 1)
i = VEXPORT;
}
listsetvar(list, i);
}
/* Tight loop with builtins only:
* "while kill -0 $child; do true; done"
* will never exit even if $child died, unless we do this
* to reap the zombie and make kill detect that it's gone: */
dowait(DOWAIT_NONBLOCK, NULL);
if (evalbltin(cmdentry.u.cmd, argc, argv)) {
int exit_status;
int i = exception_type;
if (i == EXEXIT)
goto raise;
exit_status = 2;
if (i == EXINT)
exit_status = 128 + SIGINT;
if (i == EXSIG)
exit_status = 128 + pending_sig;
exitstatus = exit_status;
if (i == EXINT || spclbltin > 0) {
raise:
longjmp(exception_handler->loc, 1);
}
FORCE_INT_ON;
}
break;
case CMDFUNCTION:
listsetvar(varlist.list, 0);
/* See above for the rationale */
dowait(DOWAIT_NONBLOCK, NULL);
if (evalfun(cmdentry.u.func, argc, argv, flags))
goto raise;
break;
} /* switch */
out:
popredir(/*drop:*/ cmd_is_exec, /*restore:*/ cmd_is_exec);
if (lastarg) {
/* dsl: I think this is intended to be used to support
* '_' in 'vi' command mode during line editing...
* However I implemented that within libedit itself.
*/
setvar("_", lastarg, 0);
}
popstackmark(&smark);
}
static int
evalbltin(const struct builtincmd *cmd, int argc, char **argv)
{
char *volatile savecmdname;
struct jmploc *volatile savehandler;
struct jmploc jmploc;
int i;
savecmdname = commandname;
i = setjmp(jmploc.loc);
if (i)
goto cmddone;
savehandler = exception_handler;
exception_handler = &jmploc;
commandname = argv[0];
argptr = argv + 1;
optptr = NULL; /* initialize nextopt */
exitstatus = (*cmd->builtin)(argc, argv);
flush_stdout_stderr();
cmddone:
exitstatus |= ferror(stdout);
clearerr(stdout);
commandname = savecmdname;
exception_handler = savehandler;
return i;
}
static int
goodname(const char *p)
{
return !*endofname(p);
}
/*
* Search for a command. This is called before we fork so that the
* location of the command will be available in the parent as well as
* the child. The check for "goodname" is an overly conservative
* check that the name will not be subject to expansion.
*/
static void
prehash(union node *n)
{
struct cmdentry entry;
if (n->type == NCMD && n->ncmd.args && goodname(n->ncmd.args->narg.text))
find_command(n->ncmd.args->narg.text, &entry, 0, pathval());
}
/* ============ Builtin commands
*
* Builtin commands whose functions are closely tied to evaluation
* are implemented here.
*/
/*
* Handle break and continue commands. Break, continue, and return are
* all handled by setting the evalskip flag. The evaluation routines
* above all check this flag, and if it is set they start skipping
* commands rather than executing them. The variable skipcount is
* the number of loops to break/continue, or the number of function
* levels to return. (The latter is always 1.) It should probably
* be an error to break out of more loops than exist, but it isn't
* in the standard shell so we don't make it one here.
*/
static int FAST_FUNC
breakcmd(int argc UNUSED_PARAM, char **argv)
{
int n = argv[1] ? number(argv[1]) : 1;
if (n <= 0)
ash_msg_and_raise_error(msg_illnum, argv[1]);
if (n > loopnest)
n = loopnest;
if (n > 0) {
evalskip = (**argv == 'c') ? SKIPCONT : SKIPBREAK;
skipcount = n;
}
return 0;
}
/* ============ input.c
*
* This implements the input routines used by the parser.
*/
enum {
INPUT_PUSH_FILE = 1,
INPUT_NOFILE_OK = 2,
};
static smallint checkkwd;
/* values of checkkwd variable */
#define CHKALIAS 0x1
#define CHKKWD 0x2
#define CHKNL 0x4
/*
* Push a string back onto the input at this current parsefile level.
* We handle aliases this way.
*/
#if !ENABLE_ASH_ALIAS
#define pushstring(s, ap) pushstring(s)
#endif
static void
pushstring(char *s, struct alias *ap)
{
struct strpush *sp;
int len;
len = strlen(s);
INT_OFF;
if (g_parsefile->strpush) {
sp = ckzalloc(sizeof(*sp));
sp->prev = g_parsefile->strpush;
} else {
sp = &(g_parsefile->basestrpush);
}
g_parsefile->strpush = sp;
sp->prev_string = g_parsefile->next_to_pgetc;
sp->prev_left_in_line = g_parsefile->left_in_line;
#if ENABLE_ASH_ALIAS
sp->ap = ap;
if (ap) {
ap->flag |= ALIASINUSE;
sp->string = s;
}
#endif
g_parsefile->next_to_pgetc = s;
g_parsefile->left_in_line = len;
INT_ON;
}
static void
popstring(void)
{
struct strpush *sp = g_parsefile->strpush;
INT_OFF;
#if ENABLE_ASH_ALIAS
if (sp->ap) {
if (g_parsefile->next_to_pgetc[-1] == ' '
|| g_parsefile->next_to_pgetc[-1] == '\t'
) {
checkkwd |= CHKALIAS;
}
if (sp->string != sp->ap->val) {
free(sp->string);
}
sp->ap->flag &= ~ALIASINUSE;
if (sp->ap->flag & ALIASDEAD) {
unalias(sp->ap->name);
}
}
#endif
g_parsefile->next_to_pgetc = sp->prev_string;
g_parsefile->left_in_line = sp->prev_left_in_line;
g_parsefile->strpush = sp->prev;
if (sp != &(g_parsefile->basestrpush))
free(sp);
INT_ON;
}
//FIXME: BASH_COMPAT with "...&" does TWO pungetc():
//it peeks whether it is &>, and then pushes back both chars.
//This function needs to save last *next_to_pgetc to buf[0]
//to make two pungetc() reliable. Currently,
// pgetc (out of buf: does preadfd), pgetc, pungetc, pungetc won't work...
static int
preadfd(void)
{
int nr;
char *buf = g_parsefile->buf;
g_parsefile->next_to_pgetc = buf;
#if ENABLE_FEATURE_EDITING
retry:
if (!iflag || g_parsefile->fd != STDIN_FILENO)
nr = nonblock_safe_read(g_parsefile->fd, buf, IBUFSIZ - 1);
else {
#if ENABLE_FEATURE_TAB_COMPLETION
line_input_state->path_lookup = pathval();
#endif
nr = read_line_input(cmdedit_prompt, buf, IBUFSIZ, line_input_state);
if (nr == 0) {
/* Ctrl+C pressed */
if (trap[SIGINT]) {
buf[0] = '\n';
buf[1] = '\0';
raise(SIGINT);
return 1;
}
goto retry;
}
if (nr < 0 && errno == 0) {
/* Ctrl+D pressed */
nr = 0;
}
}
#else
nr = nonblock_safe_read(g_parsefile->fd, buf, IBUFSIZ - 1);
#endif
#if 0
/* nonblock_safe_read() handles this problem */
if (nr < 0) {
if (parsefile->fd == 0 && errno == EWOULDBLOCK) {
int flags = fcntl(0, F_GETFL);
if (flags >= 0 && (flags & O_NONBLOCK)) {
flags &= ~O_NONBLOCK;
if (fcntl(0, F_SETFL, flags) >= 0) {
out2str("sh: turning off NDELAY mode\n");
goto retry;
}
}
}
}
#endif
return nr;
}
/*
* Refill the input buffer and return the next input character:
*
* 1) If a string was pushed back on the input, pop it;
* 2) If an EOF was pushed back (g_parsefile->left_in_line < -BIGNUM)
* or we are reading from a string so we can't refill the buffer,
* return EOF.
* 3) If there is more stuff in this buffer, use it else call read to fill it.
* 4) Process input up to the next newline, deleting nul characters.
*/
//#define pgetc_debug(...) bb_error_msg(__VA_ARGS__)
#define pgetc_debug(...) ((void)0)
static int
preadbuffer(void)
{
char *q;
int more;
while (g_parsefile->strpush) {
#if ENABLE_ASH_ALIAS
if (g_parsefile->left_in_line == -1
&& g_parsefile->strpush->ap
&& g_parsefile->next_to_pgetc[-1] != ' '
&& g_parsefile->next_to_pgetc[-1] != '\t'
) {
pgetc_debug("preadbuffer PEOA");
return PEOA;
}
#endif
popstring();
/* try "pgetc" now: */
pgetc_debug("preadbuffer internal pgetc at %d:%p'%s'",
g_parsefile->left_in_line,
g_parsefile->next_to_pgetc,
g_parsefile->next_to_pgetc);
if (--g_parsefile->left_in_line >= 0)
return (unsigned char)(*g_parsefile->next_to_pgetc++);
}
/* on both branches above g_parsefile->left_in_line < 0.
* "pgetc" needs refilling.
*/
/* -90 is our -BIGNUM. Below we use -99 to mark "EOF on read",
* pungetc() may increment it a few times.
* Assuming it won't increment it to less than -90.
*/
if (g_parsefile->left_in_line < -90 || g_parsefile->buf == NULL) {
pgetc_debug("preadbuffer PEOF1");
/* even in failure keep left_in_line and next_to_pgetc
* in lock step, for correct multi-layer pungetc.
* left_in_line was decremented before preadbuffer(),
* must inc next_to_pgetc: */
g_parsefile->next_to_pgetc++;
return PEOF;
}
more = g_parsefile->left_in_buffer;
if (more <= 0) {
flush_stdout_stderr();
again:
more = preadfd();
if (more <= 0) {
/* don't try reading again */
g_parsefile->left_in_line = -99;
pgetc_debug("preadbuffer PEOF2");
g_parsefile->next_to_pgetc++;
return PEOF;
}
}
/* Find out where's the end of line.
* Set g_parsefile->left_in_line
* and g_parsefile->left_in_buffer acordingly.
* NUL chars are deleted.
*/
q = g_parsefile->next_to_pgetc;
for (;;) {
char c;
more--;
c = *q;
if (c == '\0') {
memmove(q, q + 1, more);
} else {
q++;
if (c == '\n') {
g_parsefile->left_in_line = q - g_parsefile->next_to_pgetc - 1;
break;
}
}
if (more <= 0) {
g_parsefile->left_in_line = q - g_parsefile->next_to_pgetc - 1;
if (g_parsefile->left_in_line < 0)
goto again;
break;
}
}
g_parsefile->left_in_buffer = more;
if (vflag) {
char save = *q;
*q = '\0';
out2str(g_parsefile->next_to_pgetc);
*q = save;
}
pgetc_debug("preadbuffer at %d:%p'%s'",
g_parsefile->left_in_line,
g_parsefile->next_to_pgetc,
g_parsefile->next_to_pgetc);
return (unsigned char)*g_parsefile->next_to_pgetc++;
}
#define pgetc_as_macro() \
(--g_parsefile->left_in_line >= 0 \
? (unsigned char)*g_parsefile->next_to_pgetc++ \
: preadbuffer() \
)
static int
pgetc(void)
{
pgetc_debug("pgetc_fast at %d:%p'%s'",
g_parsefile->left_in_line,
g_parsefile->next_to_pgetc,
g_parsefile->next_to_pgetc);
return pgetc_as_macro();
}
#if ENABLE_ASH_OPTIMIZE_FOR_SIZE
# define pgetc_fast() pgetc()
#else
# define pgetc_fast() pgetc_as_macro()
#endif
#if ENABLE_ASH_ALIAS
static int
pgetc_without_PEOA(void)
{
int c;
do {
pgetc_debug("pgetc_fast at %d:%p'%s'",
g_parsefile->left_in_line,
g_parsefile->next_to_pgetc,
g_parsefile->next_to_pgetc);
c = pgetc_fast();
} while (c == PEOA);
return c;
}
#else
# define pgetc_without_PEOA() pgetc()
#endif
/*
* Read a line from the script.
*/
static char *
pfgets(char *line, int len)
{
char *p = line;
int nleft = len;
int c;
while (--nleft > 0) {
c = pgetc_without_PEOA();
if (c == PEOF) {
if (p == line)
return NULL;
break;
}
*p++ = c;
if (c == '\n')
break;
}
*p = '\0';
return line;
}
/*
* Undo the last call to pgetc. Only one character may be pushed back.
* PEOF may be pushed back.
*/
static void
pungetc(void)
{
g_parsefile->left_in_line++;
g_parsefile->next_to_pgetc--;
pgetc_debug("pushed back to %d:%p'%s'",
g_parsefile->left_in_line,
g_parsefile->next_to_pgetc,
g_parsefile->next_to_pgetc);
}
/*
* To handle the "." command, a stack of input files is used. Pushfile
* adds a new entry to the stack and popfile restores the previous level.
*/
static void
pushfile(void)
{
struct parsefile *pf;
pf = ckzalloc(sizeof(*pf));
pf->prev = g_parsefile;
pf->fd = -1;
/*pf->strpush = NULL; - ckzalloc did it */
/*pf->basestrpush.prev = NULL;*/
g_parsefile = pf;
}
static void
popfile(void)
{
struct parsefile *pf = g_parsefile;
INT_OFF;
if (pf->fd >= 0)
close(pf->fd);
free(pf->buf);
while (pf->strpush)
popstring();
g_parsefile = pf->prev;
free(pf);
INT_ON;
}
/*
* Return to top level.
*/
static void
popallfiles(void)
{
while (g_parsefile != &basepf)
popfile();
}
/*
* Close the file(s) that the shell is reading commands from. Called
* after a fork is done.
*/
static void
closescript(void)
{
popallfiles();
if (g_parsefile->fd > 0) {
close(g_parsefile->fd);
g_parsefile->fd = 0;
}
}
/*
* Like setinputfile, but takes an open file descriptor. Call this with
* interrupts off.
*/
static void
setinputfd(int fd, int push)
{
close_on_exec_on(fd);
if (push) {
pushfile();
g_parsefile->buf = NULL;
}
g_parsefile->fd = fd;
if (g_parsefile->buf == NULL)
g_parsefile->buf = ckmalloc(IBUFSIZ);
g_parsefile->left_in_buffer = 0;
g_parsefile->left_in_line = 0;
g_parsefile->linno = 1;
}
/*
* Set the input to take input from a file. If push is set, push the
* old input onto the stack first.
*/
static int
setinputfile(const char *fname, int flags)
{
int fd;
int fd2;
INT_OFF;
fd = open(fname, O_RDONLY);
if (fd < 0) {
if (flags & INPUT_NOFILE_OK)
goto out;
ash_msg_and_raise_error("can't open '%s'", fname);
}
if (fd < 10) {
fd2 = copyfd(fd, 10);
close(fd);
if (fd2 < 0)
ash_msg_and_raise_error("out of file descriptors");
fd = fd2;
}
setinputfd(fd, flags & INPUT_PUSH_FILE);
out:
INT_ON;
return fd;
}
/*
* Like setinputfile, but takes input from a string.
*/
static void
setinputstring(char *string)
{
INT_OFF;
pushfile();
g_parsefile->next_to_pgetc = string;
g_parsefile->left_in_line = strlen(string);
g_parsefile->buf = NULL;
g_parsefile->linno = 1;
INT_ON;
}
/* ============ mail.c
*
* Routines to check for mail.
*/
#if ENABLE_ASH_MAIL
#define MAXMBOXES 10
/* times of mailboxes */
static time_t mailtime[MAXMBOXES];
/* Set if MAIL or MAILPATH is changed. */
static smallint mail_var_path_changed;
/*
* Print appropriate message(s) if mail has arrived.
* If mail_var_path_changed is set,
* then the value of MAIL has mail_var_path_changed,
* so we just update the values.
*/
static void
chkmail(void)
{
const char *mpath;
char *p;
char *q;
time_t *mtp;
struct stackmark smark;
struct stat statb;
setstackmark(&smark);
mpath = mpathset() ? mpathval() : mailval();
for (mtp = mailtime; mtp < mailtime + MAXMBOXES; mtp++) {
p = path_advance(&mpath, nullstr);
if (p == NULL)
break;
if (*p == '\0')
continue;
for (q = p; *q; q++)
continue;
#if DEBUG
if (q[-1] != '/')
abort();
#endif
q[-1] = '\0'; /* delete trailing '/' */
if (stat(p, &statb) < 0) {
*mtp = 0;
continue;
}
if (!mail_var_path_changed && statb.st_mtime != *mtp) {
fprintf(
stderr, snlfmt,
pathopt ? pathopt : "you have mail"
);
}
*mtp = statb.st_mtime;
}
mail_var_path_changed = 0;
popstackmark(&smark);
}
static void FAST_FUNC
changemail(const char *val UNUSED_PARAM)
{
mail_var_path_changed = 1;
}
#endif /* ASH_MAIL */
/* ============ ??? */
/*
* Set the shell parameters.
*/
static void
setparam(char **argv)
{
char **newparam;
char **ap;
int nparam;
for (nparam = 0; argv[nparam]; nparam++)
continue;
ap = newparam = ckmalloc((nparam + 1) * sizeof(*ap));
while (*argv) {
*ap++ = ckstrdup(*argv++);
}
*ap = NULL;
freeparam(&shellparam);
shellparam.malloced = 1;
shellparam.nparam = nparam;
shellparam.p = newparam;
#if ENABLE_ASH_GETOPTS
shellparam.optind = 1;
shellparam.optoff = -1;
#endif
}
/*
* Process shell options. The global variable argptr contains a pointer
* to the argument list; we advance it past the options.
*
* SUSv3 section 2.8.1 "Consequences of Shell Errors" says:
* For a non-interactive shell, an error condition encountered
* by a special built-in ... shall cause the shell to write a diagnostic message
* to standard error and exit as shown in the following table:
* Error Special Built-In
* ...
* Utility syntax error (option or operand error) Shall exit
* ...
* However, in bug 1142 (http://busybox.net/bugs/view.php?id=1142)
* we see that bash does not do that (set "finishes" with error code 1 instead,
* and shell continues), and people rely on this behavior!
* Testcase:
* set -o barfoo 2>/dev/null
* echo $?
*
* Oh well. Let's mimic that.
*/
static int
plus_minus_o(char *name, int val)
{
int i;
if (name) {
for (i = 0; i < NOPTS; i++) {
if (strcmp(name, optnames(i)) == 0) {
optlist[i] = val;
return 0;
}
}
ash_msg("illegal option %co %s", val ? '-' : '+', name);
return 1;
}
for (i = 0; i < NOPTS; i++) {
if (val) {
out1fmt("%-16s%s\n", optnames(i), optlist[i] ? "on" : "off");
} else {
out1fmt("set %co %s\n", optlist[i] ? '-' : '+', optnames(i));
}
}
return 0;
}
static void
setoption(int flag, int val)
{
int i;
for (i = 0; i < NOPTS; i++) {
if (optletters(i) == flag) {
optlist[i] = val;
return;
}
}
ash_msg_and_raise_error("illegal option %c%c", val ? '-' : '+', flag);
/* NOTREACHED */
}
static int
options(int cmdline)
{
char *p;
int val;
int c;
if (cmdline)
minusc = NULL;
while ((p = *argptr) != NULL) {
c = *p++;
if (c != '-' && c != '+')
break;
argptr++;
val = 0; /* val = 0 if c == '+' */
if (c == '-') {
val = 1;
if (p[0] == '\0' || LONE_DASH(p)) {
if (!cmdline) {
/* "-" means turn off -x and -v */
if (p[0] == '\0')
xflag = vflag = 0;
/* "--" means reset params */
else if (*argptr == NULL)
setparam(argptr);
}
break; /* "-" or "--" terminates options */
}
}
/* first char was + or - */
while ((c = *p++) != '\0') {
/* bash 3.2 indeed handles -c CMD and +c CMD the same */
if (c == 'c' && cmdline) {
minusc = p; /* command is after shell args */
} else if (c == 'o') {
if (plus_minus_o(*argptr, val)) {
/* it already printed err message */
return 1; /* error */
}
if (*argptr)
argptr++;
} else if (cmdline && (c == 'l')) { /* -l or +l == --login */
isloginsh = 1;
/* bash does not accept +-login, we also won't */
} else if (cmdline && val && (c == '-')) { /* long options */
if (strcmp(p, "login") == 0)
isloginsh = 1;
break;
} else {
setoption(c, val);
}
}
}
return 0;
}
/*
* The shift builtin command.
*/
static int FAST_FUNC
shiftcmd(int argc UNUSED_PARAM, char **argv)
{
int n;
char **ap1, **ap2;
n = 1;
if (argv[1])
n = number(argv[1]);
if (n > shellparam.nparam)
n = 0; /* bash compat, was = shellparam.nparam; */
INT_OFF;
shellparam.nparam -= n;
for (ap1 = shellparam.p; --n >= 0; ap1++) {
if (shellparam.malloced)
free(*ap1);
}
ap2 = shellparam.p;
while ((*ap2++ = *ap1++) != NULL)
continue;
#if ENABLE_ASH_GETOPTS
shellparam.optind = 1;
shellparam.optoff = -1;
#endif
INT_ON;
return 0;
}
/*
* POSIX requires that 'set' (but not export or readonly) output the
* variables in lexicographic order - by the locale's collating order (sigh).
* Maybe we could keep them in an ordered balanced binary tree
* instead of hashed lists.
* For now just roll 'em through qsort for printing...
*/
static int
showvars(const char *sep_prefix, int on, int off)
{
const char *sep;
char **ep, **epend;
ep = listvars(on, off, &epend);
qsort(ep, epend - ep, sizeof(char *), vpcmp);
sep = *sep_prefix ? " " : sep_prefix;
for (; ep < epend; ep++) {
const char *p;
const char *q;
p = strchrnul(*ep, '=');
q = nullstr;
if (*p)
q = single_quote(++p);
out1fmt("%s%s%.*s%s\n", sep_prefix, sep, (int)(p - *ep), *ep, q);
}
return 0;
}
/*
* The set command builtin.
*/
static int FAST_FUNC
setcmd(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
{
int retval;
if (!argv[1])
return showvars(nullstr, 0, VUNSET);
INT_OFF;
retval = 1;
if (!options(0)) { /* if no parse error... */
retval = 0;
optschanged();
if (*argptr != NULL) {
setparam(argptr);
}
}
INT_ON;
return retval;
}
#if ENABLE_ASH_RANDOM_SUPPORT
static void FAST_FUNC
change_random(const char *value)
{
uint32_t t;
if (value == NULL) {
/* "get", generate */
t = next_random(&random_gen);
/* set without recursion */
setvar(vrandom.text, utoa(t), VNOFUNC);
vrandom.flags &= ~VNOFUNC;
} else {
/* set/reset */
t = strtoul(value, NULL, 10);
INIT_RANDOM_T(&random_gen, (t ? t : 1), t);
}
}
#endif
#if ENABLE_ASH_GETOPTS
static int
getopts(char *optstr, char *optvar, char **optfirst, int *param_optind, int *optoff)
{
char *p, *q;
char c = '?';
int done = 0;
int err = 0;
char s[12];
char **optnext;
if (*param_optind < 1)
return 1;
optnext = optfirst + *param_optind - 1;
if (*param_optind <= 1 || *optoff < 0 || (int)strlen(optnext[-1]) < *optoff)
p = NULL;
else
p = optnext[-1] + *optoff;
if (p == NULL || *p == '\0') {
/* Current word is done, advance */
p = *optnext;
if (p == NULL || *p != '-' || *++p == '\0') {
atend:
p = NULL;
done = 1;
goto out;
}
optnext++;
if (LONE_DASH(p)) /* check for "--" */
goto atend;
}
c = *p++;
for (q = optstr; *q != c;) {
if (*q == '\0') {
if (optstr[0] == ':') {
s[0] = c;
s[1] = '\0';
err |= setvarsafe("OPTARG", s, 0);
} else {
fprintf(stderr, "Illegal option -%c\n", c);
unsetvar("OPTARG");
}
c = '?';
goto out;
}
if (*++q == ':')
q++;
}
if (*++q == ':') {
if (*p == '\0' && (p = *optnext) == NULL) {
if (optstr[0] == ':') {
s[0] = c;
s[1] = '\0';
err |= setvarsafe("OPTARG", s, 0);
c = ':';
} else {
fprintf(stderr, "No arg for -%c option\n", c);
unsetvar("OPTARG");
c = '?';
}
goto out;
}
if (p == *optnext)
optnext++;
err |= setvarsafe("OPTARG", p, 0);
p = NULL;
} else
err |= setvarsafe("OPTARG", nullstr, 0);
out:
*optoff = p ? p - *(optnext - 1) : -1;
*param_optind = optnext - optfirst + 1;
fmtstr(s, sizeof(s), "%d", *param_optind);
err |= setvarsafe("OPTIND", s, VNOFUNC);
s[0] = c;
s[1] = '\0';
err |= setvarsafe(optvar, s, 0);
if (err) {
*param_optind = 1;
*optoff = -1;
flush_stdout_stderr();
raise_exception(EXERROR);
}
return done;
}
/*
* The getopts builtin. Shellparam.optnext points to the next argument
* to be processed. Shellparam.optptr points to the next character to
* be processed in the current argument. If shellparam.optnext is NULL,
* then it's the first time getopts has been called.
*/
static int FAST_FUNC
getoptscmd(int argc, char **argv)
{
char **optbase;
if (argc < 3)
ash_msg_and_raise_error("usage: getopts optstring var [arg]");
if (argc == 3) {
optbase = shellparam.p;
if (shellparam.optind > shellparam.nparam + 1) {
shellparam.optind = 1;
shellparam.optoff = -1;
}
} else {
optbase = &argv[3];
if (shellparam.optind > argc - 2) {
shellparam.optind = 1;
shellparam.optoff = -1;
}
}
return getopts(argv[1], argv[2], optbase, &shellparam.optind,
&shellparam.optoff);
}
#endif /* ASH_GETOPTS */
/* ============ Shell parser */
struct heredoc {
struct heredoc *next; /* next here document in list */
union node *here; /* redirection node */
char *eofmark; /* string indicating end of input */
smallint striptabs; /* if set, strip leading tabs */
};
static smallint tokpushback; /* last token pushed back */
static smallint parsebackquote; /* nonzero if we are inside backquotes */
static smallint quoteflag; /* set if (part of) last token was quoted */
static token_id_t lasttoken; /* last token read (integer id Txxx) */
static struct heredoc *heredoclist; /* list of here documents to read */
static char *wordtext; /* text of last word returned by readtoken */
static struct nodelist *backquotelist;
static union node *redirnode;
static struct heredoc *heredoc;
static const char *
tokname(char *buf, int tok)
{
if (tok < TSEMI)
return tokname_array[tok] + 1;
sprintf(buf, "\"%s\"", tokname_array[tok] + 1);
return buf;
}
/* raise_error_unexpected_syntax:
* Called when an unexpected token is read during the parse. The argument
* is the token that is expected, or -1 if more than one type of token can
* occur at this point.
*/
static void raise_error_unexpected_syntax(int) NORETURN;
static void
raise_error_unexpected_syntax(int token)
{
char msg[64];
char buf[16];
int l;
l = sprintf(msg, "unexpected %s", tokname(buf, lasttoken));
if (token >= 0)
sprintf(msg + l, " (expecting %s)", tokname(buf, token));
raise_error_syntax(msg);
/* NOTREACHED */
}
#define EOFMARKLEN 79
/* parsing is heavily cross-recursive, need these forward decls */
static union node *andor(void);
static union node *pipeline(void);
static union node *parse_command(void);
static void parseheredoc(void);
static char peektoken(void);
static int readtoken(void);
static union node *
list(int nlflag)
{
union node *n1, *n2, *n3;
int tok;
checkkwd = CHKNL | CHKKWD | CHKALIAS;
if (nlflag == 2 && peektoken())
return NULL;
n1 = NULL;
for (;;) {
n2 = andor();
tok = readtoken();
if (tok == TBACKGND) {
if (n2->type == NPIPE) {
n2->npipe.pipe_backgnd = 1;
} else {
if (n2->type != NREDIR) {
n3 = stzalloc(sizeof(struct nredir));
n3->nredir.n = n2;
/*n3->nredir.redirect = NULL; - stzalloc did it */
n2 = n3;
}
n2->type = NBACKGND;
}
}
if (n1 == NULL) {
n1 = n2;
} else {
n3 = stzalloc(sizeof(struct nbinary));
n3->type = NSEMI;
n3->nbinary.ch1 = n1;
n3->nbinary.ch2 = n2;
n1 = n3;
}
switch (tok) {
case TBACKGND:
case TSEMI:
tok = readtoken();
/* fall through */
case TNL:
if (tok == TNL) {
parseheredoc();
if (nlflag == 1)
return n1;
} else {
tokpushback = 1;
}
checkkwd = CHKNL | CHKKWD | CHKALIAS;
if (peektoken())
return n1;
break;
case TEOF:
if (heredoclist)
parseheredoc();
else
pungetc(); /* push back EOF on input */
return n1;
default:
if (nlflag == 1)
raise_error_unexpected_syntax(-1);
tokpushback = 1;
return n1;
}
}
}
static union node *
andor(void)
{
union node *n1, *n2, *n3;
int t;
n1 = pipeline();
for (;;) {
t = readtoken();
if (t == TAND) {
t = NAND;
} else if (t == TOR) {
t = NOR;
} else {
tokpushback = 1;
return n1;
}
checkkwd = CHKNL | CHKKWD | CHKALIAS;
n2 = pipeline();
n3 = stzalloc(sizeof(struct nbinary));
n3->type = t;
n3->nbinary.ch1 = n1;
n3->nbinary.ch2 = n2;
n1 = n3;
}
}
static union node *
pipeline(void)
{
union node *n1, *n2, *pipenode;
struct nodelist *lp, *prev;
int negate;
negate = 0;
TRACE(("pipeline: entered\n"));
if (readtoken() == TNOT) {
negate = !negate;
checkkwd = CHKKWD | CHKALIAS;
} else
tokpushback = 1;
n1 = parse_command();
if (readtoken() == TPIPE) {
pipenode = stzalloc(sizeof(struct npipe));
pipenode->type = NPIPE;
/*pipenode->npipe.pipe_backgnd = 0; - stzalloc did it */
lp = stzalloc(sizeof(struct nodelist));
pipenode->npipe.cmdlist = lp;
lp->n = n1;
do {
prev = lp;
lp = stzalloc(sizeof(struct nodelist));
checkkwd = CHKNL | CHKKWD | CHKALIAS;
lp->n = parse_command();
prev->next = lp;
} while (readtoken() == TPIPE);
lp->next = NULL;
n1 = pipenode;
}
tokpushback = 1;
if (negate) {
n2 = stzalloc(sizeof(struct nnot));
n2->type = NNOT;
n2->nnot.com = n1;
return n2;
}
return n1;
}
static union node *
makename(void)
{
union node *n;
n = stzalloc(sizeof(struct narg));
n->type = NARG;
/*n->narg.next = NULL; - stzalloc did it */
n->narg.text = wordtext;
n->narg.backquote = backquotelist;
return n;
}
static void
fixredir(union node *n, const char *text, int err)
{
int fd;
TRACE(("Fix redir %s %d\n", text, err));
if (!err)
n->ndup.vname = NULL;
fd = bb_strtou(text, NULL, 10);
if (!errno && fd >= 0)
n->ndup.dupfd = fd;
else if (LONE_DASH(text))
n->ndup.dupfd = -1;
else {
if (err)
raise_error_syntax("bad fd number");
n->ndup.vname = makename();
}
}
/*
* Returns true if the text contains nothing to expand (no dollar signs
* or backquotes).
*/
static int
noexpand(const char *text)
{
unsigned char c;
while ((c = *text++) != '\0') {
if (c == CTLQUOTEMARK)
continue;
if (c == CTLESC)
text++;
else if (SIT(c, BASESYNTAX) == CCTL)
return 0;
}
return 1;
}
static void
parsefname(void)
{
union node *n = redirnode;
if (readtoken() != TWORD)
raise_error_unexpected_syntax(-1);
if (n->type == NHERE) {
struct heredoc *here = heredoc;
struct heredoc *p;
int i;
if (quoteflag == 0)
n->type = NXHERE;
TRACE(("Here document %d\n", n->type));
if (!noexpand(wordtext) || (i = strlen(wordtext)) == 0 || i > EOFMARKLEN)
raise_error_syntax("illegal eof marker for << redirection");
rmescapes(wordtext, 0);
here->eofmark = wordtext;
here->next = NULL;
if (heredoclist == NULL)
heredoclist = here;
else {
for (p = heredoclist; p->next; p = p->next)
continue;
p->next = here;
}
} else if (n->type == NTOFD || n->type == NFROMFD) {
fixredir(n, wordtext, 0);
} else {
n->nfile.fname = makename();
}
}
static union node *
simplecmd(void)
{
union node *args, **app;
union node *n = NULL;
union node *vars, **vpp;
union node **rpp, *redir;
int savecheckkwd;
#if ENABLE_ASH_BASH_COMPAT
smallint double_brackets_flag = 0;
#endif
args = NULL;
app = &args;
vars = NULL;
vpp = &vars;
redir = NULL;
rpp = &redir;
savecheckkwd = CHKALIAS;
for (;;) {
int t;
checkkwd = savecheckkwd;
t = readtoken();
switch (t) {
#if ENABLE_ASH_BASH_COMPAT
case TAND: /* "&&" */
case TOR: /* "||" */
if (!double_brackets_flag) {
tokpushback = 1;
goto out;
}
wordtext = (char *) (t == TAND ? "-a" : "-o");
#endif
case TWORD:
n = stzalloc(sizeof(struct narg));
n->type = NARG;
/*n->narg.next = NULL; - stzalloc did it */
n->narg.text = wordtext;
#if ENABLE_ASH_BASH_COMPAT
if (strcmp("[[", wordtext) == 0)
double_brackets_flag = 1;
else if (strcmp("]]", wordtext) == 0)
double_brackets_flag = 0;
#endif
n->narg.backquote = backquotelist;
if (savecheckkwd && isassignment(wordtext)) {
*vpp = n;
vpp = &n->narg.next;
} else {
*app = n;
app = &n->narg.next;
savecheckkwd = 0;
}
break;
case TREDIR:
*rpp = n = redirnode;
rpp = &n->nfile.next;
parsefname(); /* read name of redirection file */
break;
case TLP:
if (args && app == &args->narg.next
&& !vars && !redir
) {
struct builtincmd *bcmd;
const char *name;
/* We have a function */
if (readtoken() != TRP)
raise_error_unexpected_syntax(TRP);
name = n->narg.text;
if (!goodname(name)
|| ((bcmd = find_builtin(name)) && IS_BUILTIN_SPECIAL(bcmd))
) {
raise_error_syntax("bad function name");
}
n->type = NDEFUN;
checkkwd = CHKNL | CHKKWD | CHKALIAS;
n->narg.next = parse_command();
return n;
}
/* fall through */
default:
tokpushback = 1;
goto out;
}
}
out:
*app = NULL;
*vpp = NULL;
*rpp = NULL;
n = stzalloc(sizeof(struct ncmd));
n->type = NCMD;
n->ncmd.args = args;
n->ncmd.assign = vars;
n->ncmd.redirect = redir;
return n;
}
static union node *
parse_command(void)
{
union node *n1, *n2;
union node *ap, **app;
union node *cp, **cpp;
union node *redir, **rpp;
union node **rpp2;
int t;
redir = NULL;
rpp2 = &redir;
switch (readtoken()) {
default:
raise_error_unexpected_syntax(-1);
/* NOTREACHED */
case TIF:
n1 = stzalloc(sizeof(struct nif));
n1->type = NIF;
n1->nif.test = list(0);
if (readtoken() != TTHEN)
raise_error_unexpected_syntax(TTHEN);
n1->nif.ifpart = list(0);
n2 = n1;
while (readtoken() == TELIF) {
n2->nif.elsepart = stzalloc(sizeof(struct nif));
n2 = n2->nif.elsepart;
n2->type = NIF;
n2->nif.test = list(0);
if (readtoken() != TTHEN)
raise_error_unexpected_syntax(TTHEN);
n2->nif.ifpart = list(0);
}
if (lasttoken == TELSE)
n2->nif.elsepart = list(0);
else {
n2->nif.elsepart = NULL;
tokpushback = 1;
}
t = TFI;
break;
case TWHILE:
case TUNTIL: {
int got;
n1 = stzalloc(sizeof(struct nbinary));
n1->type = (lasttoken == TWHILE) ? NWHILE : NUNTIL;
n1->nbinary.ch1 = list(0);
got = readtoken();
if (got != TDO) {
TRACE(("expecting DO got '%s' %s\n", tokname_array[got] + 1,
got == TWORD ? wordtext : ""));
raise_error_unexpected_syntax(TDO);
}
n1->nbinary.ch2 = list(0);
t = TDONE;
break;
}
case TFOR:
if (readtoken() != TWORD || quoteflag || !goodname(wordtext))
raise_error_syntax("bad for loop variable");
n1 = stzalloc(sizeof(struct nfor));
n1->type = NFOR;
n1->nfor.var = wordtext;
checkkwd = CHKKWD | CHKALIAS;
if (readtoken() == TIN) {
app = &ap;
while (readtoken() == TWORD) {
n2 = stzalloc(sizeof(struct narg));
n2->type = NARG;
/*n2->narg.next = NULL; - stzalloc did it */
n2->narg.text = wordtext;
n2->narg.backquote = backquotelist;
*app = n2;
app = &n2->narg.next;
}
*app = NULL;
n1->nfor.args = ap;
if (lasttoken != TNL && lasttoken != TSEMI)
raise_error_unexpected_syntax(-1);
} else {
n2 = stzalloc(sizeof(struct narg));
n2->type = NARG;
/*n2->narg.next = NULL; - stzalloc did it */
n2->narg.text = (char *)dolatstr;
/*n2->narg.backquote = NULL;*/
n1->nfor.args = n2;
/*
* Newline or semicolon here is optional (but note
* that the original Bourne shell only allowed NL).
*/
if (lasttoken != TNL && lasttoken != TSEMI)
tokpushback = 1;
}
checkkwd = CHKNL | CHKKWD | CHKALIAS;
if (readtoken() != TDO)
raise_error_unexpected_syntax(TDO);
n1->nfor.body = list(0);
t = TDONE;
break;
case TCASE:
n1 = stzalloc(sizeof(struct ncase));
n1->type = NCASE;
if (readtoken() != TWORD)
raise_error_unexpected_syntax(TWORD);
n1->ncase.expr = n2 = stzalloc(sizeof(struct narg));
n2->type = NARG;
/*n2->narg.next = NULL; - stzalloc did it */
n2->narg.text = wordtext;
n2->narg.backquote = backquotelist;
do {
checkkwd = CHKKWD | CHKALIAS;
} while (readtoken() == TNL);
if (lasttoken != TIN)
raise_error_unexpected_syntax(TIN);
cpp = &n1->ncase.cases;
next_case:
checkkwd = CHKNL | CHKKWD;
t = readtoken();
while (t != TESAC) {
if (lasttoken == TLP)
readtoken();
*cpp = cp = stzalloc(sizeof(struct nclist));
cp->type = NCLIST;
app = &cp->nclist.pattern;
for (;;) {
*app = ap = stzalloc(sizeof(struct narg));
ap->type = NARG;
/*ap->narg.next = NULL; - stzalloc did it */
ap->narg.text = wordtext;
ap->narg.backquote = backquotelist;
if (readtoken() != TPIPE)
break;
app = &ap->narg.next;
readtoken();
}
//ap->narg.next = NULL;
if (lasttoken != TRP)
raise_error_unexpected_syntax(TRP);
cp->nclist.body = list(2);
cpp = &cp->nclist.next;
checkkwd = CHKNL | CHKKWD;
t = readtoken();
if (t != TESAC) {
if (t != TENDCASE)
raise_error_unexpected_syntax(TENDCASE);
goto next_case;
}
}
*cpp = NULL;
goto redir;
case TLP:
n1 = stzalloc(sizeof(struct nredir));
n1->type = NSUBSHELL;
n1->nredir.n = list(0);
/*n1->nredir.redirect = NULL; - stzalloc did it */
t = TRP;
break;
case TBEGIN:
n1 = list(0);
t = TEND;
break;
case TWORD:
case TREDIR:
tokpushback = 1;
return simplecmd();
}
if (readtoken() != t)
raise_error_unexpected_syntax(t);
redir:
/* Now check for redirection which may follow command */
checkkwd = CHKKWD | CHKALIAS;
rpp = rpp2;
while (readtoken() == TREDIR) {
*rpp = n2 = redirnode;
rpp = &n2->nfile.next;
parsefname();
}
tokpushback = 1;
*rpp = NULL;
if (redir) {
if (n1->type != NSUBSHELL) {
n2 = stzalloc(sizeof(struct nredir));
n2->type = NREDIR;
n2->nredir.n = n1;
n1 = n2;
}
n1->nredir.redirect = redir;
}
return n1;
}
#if ENABLE_ASH_BASH_COMPAT
static int decode_dollar_squote(void)
{
static const char C_escapes[] ALIGN1 = "nrbtfav""x\\01234567";
int c, cnt;
char *p;
char buf[4];
c = pgetc();
p = strchr(C_escapes, c);
if (p) {
buf[0] = c;
p = buf;
cnt = 3;
if ((unsigned char)(c - '0') <= 7) { /* \ooo */
do {
c = pgetc();
*++p = c;
} while ((unsigned char)(c - '0') <= 7 && --cnt);
pungetc();
} else if (c == 'x') { /* \xHH */
do {
c = pgetc();
*++p = c;
} while (isxdigit(c) && --cnt);
pungetc();
if (cnt == 3) { /* \x but next char is "bad" */
c = 'x';
goto unrecognized;
}
} else { /* simple seq like \\ or \t */
p++;
}
*p = '\0';
p = buf;
c = bb_process_escape_sequence((void*)&p);
} else { /* unrecognized "\z": print both chars unless ' or " */
if (c != '\'' && c != '"') {
unrecognized:
c |= 0x100; /* "please encode \, then me" */
}
}
return c;
}
#endif
/*
* If eofmark is NULL, read a word or a redirection symbol. If eofmark
* is not NULL, read a here document. In the latter case, eofmark is the
* word which marks the end of the document and striptabs is true if
* leading tabs should be stripped from the document. The argument c
* is the first character of the input token or document.
*
* Because C does not have internal subroutines, I have simulated them
* using goto's to implement the subroutine linkage. The following macros
* will run code that appears at the end of readtoken1.
*/
#define CHECKEND() {goto checkend; checkend_return:;}
#define PARSEREDIR() {goto parseredir; parseredir_return:;}
#define PARSESUB() {goto parsesub; parsesub_return:;}
#define PARSEBACKQOLD() {oldstyle = 1; goto parsebackq; parsebackq_oldreturn:;}
#define PARSEBACKQNEW() {oldstyle = 0; goto parsebackq; parsebackq_newreturn:;}
#define PARSEARITH() {goto parsearith; parsearith_return:;}
static int
readtoken1(int c, int syntax, char *eofmark, int striptabs)
{
/* NB: syntax parameter fits into smallint */
/* c parameter is an unsigned char or PEOF or PEOA */
char *out;
int len;
char line[EOFMARKLEN + 1];
struct nodelist *bqlist;
smallint quotef;
smallint dblquote;
smallint oldstyle;
smallint prevsyntax; /* syntax before arithmetic */
#if ENABLE_ASH_EXPAND_PRMT
smallint pssyntax; /* we are expanding a prompt string */
#endif
int varnest; /* levels of variables expansion */
int arinest; /* levels of arithmetic expansion */
int parenlevel; /* levels of parens in arithmetic */
int dqvarnest; /* levels of variables expansion within double quotes */
IF_ASH_BASH_COMPAT(smallint bash_dollar_squote = 0;)
#if __GNUC__
/* Avoid longjmp clobbering */
(void) &out;
(void) &quotef;
(void) &dblquote;
(void) &varnest;
(void) &arinest;
(void) &parenlevel;
(void) &dqvarnest;
(void) &oldstyle;
(void) &prevsyntax;
(void) &syntax;
#endif
startlinno = g_parsefile->linno;
bqlist = NULL;
quotef = 0;
oldstyle = 0;
prevsyntax = 0;
#if ENABLE_ASH_EXPAND_PRMT
pssyntax = (syntax == PSSYNTAX);
if (pssyntax)
syntax = DQSYNTAX;
#endif
dblquote = (syntax == DQSYNTAX);
varnest = 0;
arinest = 0;
parenlevel = 0;
dqvarnest = 0;
STARTSTACKSTR(out);
loop:
/* For each line, until end of word */
{
CHECKEND(); /* set c to PEOF if at end of here document */
for (;;) { /* until end of line or end of word */
CHECKSTRSPACE(4, out); /* permit 4 calls to USTPUTC */
switch (SIT(c, syntax)) {
case CNL: /* '\n' */
if (syntax == BASESYNTAX)
goto endword; /* exit outer loop */
USTPUTC(c, out);
g_parsefile->linno++;
if (doprompt)
setprompt(2);
c = pgetc();
goto loop; /* continue outer loop */
case CWORD:
USTPUTC(c, out);
break;
case CCTL:
if (eofmark == NULL || dblquote)
USTPUTC(CTLESC, out);
#if ENABLE_ASH_BASH_COMPAT
if (c == '\\' && bash_dollar_squote) {
c = decode_dollar_squote();
if (c & 0x100) {
USTPUTC('\\', out);
c = (unsigned char)c;
}
}
#endif
USTPUTC(c, out);
break;
case CBACK: /* backslash */
c = pgetc_without_PEOA();
if (c == PEOF) {
USTPUTC(CTLESC, out);
USTPUTC('\\', out);
pungetc();
} else if (c == '\n') {
if (doprompt)
setprompt(2);
} else {
#if ENABLE_ASH_EXPAND_PRMT
if (c == '$' && pssyntax) {
USTPUTC(CTLESC, out);
USTPUTC('\\', out);
}
#endif
if (dblquote && c != '\\'
&& c != '`' && c != '$'
&& (c != '"' || eofmark != NULL)
) {
USTPUTC(CTLESC, out);
USTPUTC('\\', out);
}
if (SIT(c, SQSYNTAX) == CCTL)
USTPUTC(CTLESC, out);
USTPUTC(c, out);
quotef = 1;
}
break;
case CSQUOTE:
syntax = SQSYNTAX;
quotemark:
if (eofmark == NULL) {
USTPUTC(CTLQUOTEMARK, out);
}
break;
case CDQUOTE:
syntax = DQSYNTAX;
dblquote = 1;
goto quotemark;
case CENDQUOTE:
IF_ASH_BASH_COMPAT(bash_dollar_squote = 0;)
if (eofmark != NULL && arinest == 0
&& varnest == 0
) {
USTPUTC(c, out);
} else {
if (dqvarnest == 0) {
syntax = BASESYNTAX;
dblquote = 0;
}
quotef = 1;
goto quotemark;
}
break;
case CVAR: /* '$' */
PARSESUB(); /* parse substitution */
break;
case CENDVAR: /* '}' */
if (varnest > 0) {
varnest--;
if (dqvarnest > 0) {
dqvarnest--;
}
USTPUTC(CTLENDVAR, out);
} else {
USTPUTC(c, out);
}
break;
#if ENABLE_SH_MATH_SUPPORT
case CLP: /* '(' in arithmetic */
parenlevel++;
USTPUTC(c, out);
break;
case CRP: /* ')' in arithmetic */
if (parenlevel > 0) {
USTPUTC(c, out);
--parenlevel;
} else {
if (pgetc() == ')') {
if (--arinest == 0) {
USTPUTC(CTLENDARI, out);
syntax = prevsyntax;
dblquote = (syntax == DQSYNTAX);
} else
USTPUTC(')', out);
} else {
/*
* unbalanced parens
* (don't 2nd guess - no error)
*/
pungetc();
USTPUTC(')', out);
}
}
break;
#endif
case CBQUOTE: /* '`' */
PARSEBACKQOLD();
break;
case CENDFILE:
goto endword; /* exit outer loop */
case CIGN:
break;
default:
if (varnest == 0) {
#if ENABLE_ASH_BASH_COMPAT
if (c == '&') {
if (pgetc() == '>')
c = 0x100 + '>'; /* flag &> */
pungetc();
}
#endif
goto endword; /* exit outer loop */
}
IF_ASH_ALIAS(if (c != PEOA))
USTPUTC(c, out);
}
c = pgetc_fast();
} /* for (;;) */
}
endword:
#if ENABLE_SH_MATH_SUPPORT
if (syntax == ARISYNTAX)
raise_error_syntax("missing '))'");
#endif
if (syntax != BASESYNTAX && !parsebackquote && eofmark == NULL)
raise_error_syntax("unterminated quoted string");
if (varnest != 0) {
startlinno = g_parsefile->linno;
/* { */
raise_error_syntax("missing '}'");
}
USTPUTC('\0', out);
len = out - (char *)stackblock();
out = stackblock();
if (eofmark == NULL) {
if ((c == '>' || c == '<' IF_ASH_BASH_COMPAT( || c == 0x100 + '>'))
&& quotef == 0
) {
if (isdigit_str9(out)) {
PARSEREDIR(); /* passed as params: out, c */
lasttoken = TREDIR;
return lasttoken;
}
/* else: non-number X seen, interpret it
* as "NNNX>file" = "NNNX >file" */
}
pungetc();
}
quoteflag = quotef;
backquotelist = bqlist;
grabstackblock(len);
wordtext = out;
lasttoken = TWORD;
return lasttoken;
/* end of readtoken routine */
/*
* Check to see whether we are at the end of the here document. When this
* is called, c is set to the first character of the next input line. If
* we are at the end of the here document, this routine sets the c to PEOF.
*/
checkend: {
if (eofmark) {
#if ENABLE_ASH_ALIAS
if (c == PEOA)
c = pgetc_without_PEOA();
#endif
if (striptabs) {
while (c == '\t') {
c = pgetc_without_PEOA();
}
}
if (c == *eofmark) {
if (pfgets(line, sizeof(line)) != NULL) {
char *p, *q;
p = line;
for (q = eofmark + 1; *q && *p == *q; p++, q++)
continue;
if (*p == '\n' && *q == '\0') {
c = PEOF;
g_parsefile->linno++;
needprompt = doprompt;
} else {
pushstring(line, NULL);
}
}
}
}
goto checkend_return;
}
/*
* Parse a redirection operator. The variable "out" points to a string
* specifying the fd to be redirected. The variable "c" contains the
* first character of the redirection operator.
*/
parseredir: {
/* out is already checked to be a valid number or "" */
int fd = (*out == '\0' ? -1 : atoi(out));
union node *np;
np = stzalloc(sizeof(struct nfile));
if (c == '>') {
np->nfile.fd = 1;
c = pgetc();
if (c == '>')
np->type = NAPPEND;
else if (c == '|')
np->type = NCLOBBER;
else if (c == '&')
np->type = NTOFD;
/* it also can be NTO2 (>&file), but we can't figure it out yet */
else {
np->type = NTO;
pungetc();
}
}
#if ENABLE_ASH_BASH_COMPAT
else if (c == 0x100 + '>') { /* this flags &> redirection */
np->nfile.fd = 1;
pgetc(); /* this is '>', no need to check */
np->type = NTO2;
}
#endif
else { /* c == '<' */
/*np->nfile.fd = 0; - stzalloc did it */
c = pgetc();
switch (c) {
case '<':
if (sizeof(struct nfile) != sizeof(struct nhere)) {
np = stzalloc(sizeof(struct nhere));
/*np->nfile.fd = 0; - stzalloc did it */
}
np->type = NHERE;
heredoc = stzalloc(sizeof(struct heredoc));
heredoc->here = np;
c = pgetc();
if (c == '-') {
heredoc->striptabs = 1;
} else {
/*heredoc->striptabs = 0; - stzalloc did it */
pungetc();
}
break;
case '&':
np->type = NFROMFD;
break;
case '>':
np->type = NFROMTO;
break;
default:
np->type = NFROM;
pungetc();
break;
}
}
if (fd >= 0)
np->nfile.fd = fd;
redirnode = np;
goto parseredir_return;
}
/*
* Parse a substitution. At this point, we have read the dollar sign
* and nothing else.
*/
/* is_special(c) evaluates to 1 for c in "!#$*-0123456789?@"; 0 otherwise
* (assuming ascii char codes, as the original implementation did) */
#define is_special(c) \
(((unsigned)(c) - 33 < 32) \
&& ((0xc1ff920dU >> ((unsigned)(c) - 33)) & 1))
parsesub: {
unsigned char subtype;
int typeloc;
int flags;
char *p;
static const char types[] ALIGN1 = "}-+?=";
c = pgetc();
if (c > 255 /* PEOA or PEOF */
|| (c != '(' && c != '{' && !is_name(c) && !is_special(c))
) {
#if ENABLE_ASH_BASH_COMPAT
if (c == '\'')
bash_dollar_squote = 1;
else
#endif
USTPUTC('$', out);
pungetc();
} else if (c == '(') { /* $(command) or $((arith)) */
if (pgetc() == '(') {
#if ENABLE_SH_MATH_SUPPORT
PARSEARITH();
#else
raise_error_syntax("you disabled math support for $((arith)) syntax");
#endif
} else {
pungetc();
PARSEBACKQNEW();
}
} else {
USTPUTC(CTLVAR, out);
typeloc = out - (char *)stackblock();
USTPUTC(VSNORMAL, out);
subtype = VSNORMAL;
if (c == '{') {
c = pgetc();
if (c == '#') {
c = pgetc();
if (c == '}')
c = '#';
else
subtype = VSLENGTH;
} else
subtype = 0;
}
if (c <= 255 /* not PEOA or PEOF */ && is_name(c)) {
do {
STPUTC(c, out);
c = pgetc();
} while (c <= 255 /* not PEOA or PEOF */ && is_in_name(c));
} else if (isdigit(c)) {
do {
STPUTC(c, out);
c = pgetc();
} while (isdigit(c));
} else if (is_special(c)) {
USTPUTC(c, out);
c = pgetc();
} else {
badsub:
raise_error_syntax("bad substitution");
}
if (c != '}' && subtype == VSLENGTH)
goto badsub;
STPUTC('=', out);
flags = 0;
if (subtype == 0) {
switch (c) {
case ':':
c = pgetc();
#if ENABLE_ASH_BASH_COMPAT
if (c == ':' || c == '$' || isdigit(c)) {
pungetc();
subtype = VSSUBSTR;
break;
}
#endif
flags = VSNUL;
/*FALLTHROUGH*/
default:
p = strchr(types, c);
if (p == NULL)
goto badsub;
subtype = p - types + VSNORMAL;
break;
case '%':
case '#': {
int cc = c;
subtype = c == '#' ? VSTRIMLEFT : VSTRIMRIGHT;
c = pgetc();
if (c == cc)
subtype++;
else
pungetc();
break;
}
#if ENABLE_ASH_BASH_COMPAT
case '/':
subtype = VSREPLACE;
c = pgetc();
if (c == '/')
subtype++; /* VSREPLACEALL */
else
pungetc();
break;
#endif
}
} else {
pungetc();
}
if (dblquote || arinest)
flags |= VSQUOTE;
((unsigned char *)stackblock())[typeloc] = subtype | flags;
if (subtype != VSNORMAL) {
varnest++;
if (dblquote || arinest) {
dqvarnest++;
}
}
}
goto parsesub_return;
}
/*
* Called to parse command substitutions. Newstyle is set if the command
* is enclosed inside $(...); nlpp is a pointer to the head of the linked
* list of commands (passed by reference), and savelen is the number of
* characters on the top of the stack which must be preserved.
*/
parsebackq: {
struct nodelist **nlpp;
smallint savepbq;
union node *n;
char *volatile str;
struct jmploc jmploc;
struct jmploc *volatile savehandler;
size_t savelen;
smallint saveprompt = 0;
#ifdef __GNUC__
(void) &saveprompt;
#endif
savepbq = parsebackquote;
if (setjmp(jmploc.loc)) {
free(str);
parsebackquote = 0;
exception_handler = savehandler;
longjmp(exception_handler->loc, 1);
}
INT_OFF;
str = NULL;
savelen = out - (char *)stackblock();
if (savelen > 0) {
str = ckmalloc(savelen);
memcpy(str, stackblock(), savelen);
}
savehandler = exception_handler;
exception_handler = &jmploc;
INT_ON;
if (oldstyle) {
/* We must read until the closing backquote, giving special
treatment to some slashes, and then push the string and
reread it as input, interpreting it normally. */
char *pout;
int pc;
size_t psavelen;
char *pstr;
STARTSTACKSTR(pout);
for (;;) {
if (needprompt) {
setprompt(2);
}
pc = pgetc();
switch (pc) {
case '`':
goto done;
case '\\':
pc = pgetc();
if (pc == '\n') {
g_parsefile->linno++;
if (doprompt)
setprompt(2);
/*
* If eating a newline, avoid putting
* the newline into the new character
* stream (via the STPUTC after the
* switch).
*/
continue;
}
if (pc != '\\' && pc != '`' && pc != '$'
&& (!dblquote || pc != '"')
) {
STPUTC('\\', pout);
}
if (pc <= 255 /* not PEOA or PEOF */) {
break;
}
/* fall through */
case PEOF:
IF_ASH_ALIAS(case PEOA:)
startlinno = g_parsefile->linno;
raise_error_syntax("EOF in backquote substitution");
case '\n':
g_parsefile->linno++;
needprompt = doprompt;
break;
default:
break;
}
STPUTC(pc, pout);
}
done:
STPUTC('\0', pout);
psavelen = pout - (char *)stackblock();
if (psavelen > 0) {
pstr = grabstackstr(pout);
setinputstring(pstr);
}
}
nlpp = &bqlist;
while (*nlpp)
nlpp = &(*nlpp)->next;
*nlpp = stzalloc(sizeof(**nlpp));
/* (*nlpp)->next = NULL; - stzalloc did it */
parsebackquote = oldstyle;
if (oldstyle) {
saveprompt = doprompt;
doprompt = 0;
}
n = list(2);
if (oldstyle)
doprompt = saveprompt;
else if (readtoken() != TRP)
raise_error_unexpected_syntax(TRP);
(*nlpp)->n = n;
if (oldstyle) {
/*
* Start reading from old file again, ignoring any pushed back
* tokens left from the backquote parsing
*/
popfile();
tokpushback = 0;
}
while (stackblocksize() <= savelen)
growstackblock();
STARTSTACKSTR(out);
if (str) {
memcpy(out, str, savelen);
STADJUST(savelen, out);
INT_OFF;
free(str);
str = NULL;
INT_ON;
}
parsebackquote = savepbq;
exception_handler = savehandler;
if (arinest || dblquote)
USTPUTC(CTLBACKQ | CTLQUOTE, out);
else
USTPUTC(CTLBACKQ, out);
if (oldstyle)
goto parsebackq_oldreturn;
goto parsebackq_newreturn;
}
#if ENABLE_SH_MATH_SUPPORT
/*
* Parse an arithmetic expansion (indicate start of one and set state)
*/
parsearith: {
if (++arinest == 1) {
prevsyntax = syntax;
syntax = ARISYNTAX;
USTPUTC(CTLARI, out);
if (dblquote)
USTPUTC('"', out);
else
USTPUTC(' ', out);
} else {
/*
* we collapse embedded arithmetic expansion to
* parenthesis, which should be equivalent
*/
USTPUTC('(', out);
}
goto parsearith_return;
}
#endif
} /* end of readtoken */
/*
* Read the next input token.
* If the token is a word, we set backquotelist to the list of cmds in
* backquotes. We set quoteflag to true if any part of the word was
* quoted.
* If the token is TREDIR, then we set redirnode to a structure containing
* the redirection.
* In all cases, the variable startlinno is set to the number of the line
* on which the token starts.
*
* [Change comment: here documents and internal procedures]
* [Readtoken shouldn't have any arguments. Perhaps we should make the
* word parsing code into a separate routine. In this case, readtoken
* doesn't need to have any internal procedures, but parseword does.
* We could also make parseoperator in essence the main routine, and
* have parseword (readtoken1?) handle both words and redirection.]
*/
#define NEW_xxreadtoken
#ifdef NEW_xxreadtoken
/* singles must be first! */
static const char xxreadtoken_chars[7] ALIGN1 = {
'\n', '(', ')', /* singles */
'&', '|', ';', /* doubles */
0
};
#define xxreadtoken_singles 3
#define xxreadtoken_doubles 3
static const char xxreadtoken_tokens[] ALIGN1 = {
TNL, TLP, TRP, /* only single occurrence allowed */
TBACKGND, TPIPE, TSEMI, /* if single occurrence */
TEOF, /* corresponds to trailing nul */
TAND, TOR, TENDCASE /* if double occurrence */
};
static int
xxreadtoken(void)
{
int c;
if (tokpushback) {
tokpushback = 0;
return lasttoken;
}
if (needprompt) {
setprompt(2);
}
startlinno = g_parsefile->linno;
for (;;) { /* until token or start of word found */
c = pgetc_fast();
if (c == ' ' || c == '\t' IF_ASH_ALIAS( || c == PEOA))
continue;
if (c == '#') {
while ((c = pgetc()) != '\n' && c != PEOF)
continue;
pungetc();
} else if (c == '\\') {
if (pgetc() != '\n') {
pungetc();
break; /* return readtoken1(...) */
}
startlinno = ++g_parsefile->linno;
if (doprompt)
setprompt(2);
} else {
const char *p;
p = xxreadtoken_chars + sizeof(xxreadtoken_chars) - 1;
if (c != PEOF) {
if (c == '\n') {
g_parsefile->linno++;
needprompt = doprompt;
}
p = strchr(xxreadtoken_chars, c);
if (p == NULL)
break; /* return readtoken1(...) */
if ((int)(p - xxreadtoken_chars) >= xxreadtoken_singles) {
int cc = pgetc();
if (cc == c) { /* double occurrence? */
p += xxreadtoken_doubles + 1;
} else {
pungetc();
#if ENABLE_ASH_BASH_COMPAT
if (c == '&' && cc == '>') /* &> */
break; /* return readtoken1(...) */
#endif
}
}
}
lasttoken = xxreadtoken_tokens[p - xxreadtoken_chars];
return lasttoken;
}
} /* for (;;) */
return readtoken1(c, BASESYNTAX, (char *) NULL, 0);
}
#else /* old xxreadtoken */
#define RETURN(token) return lasttoken = token
static int
xxreadtoken(void)
{
int c;
if (tokpushback) {
tokpushback = 0;
return lasttoken;
}
if (needprompt) {
setprompt(2);
}
startlinno = g_parsefile->linno;
for (;;) { /* until token or start of word found */
c = pgetc_fast();
switch (c) {
case ' ': case '\t':
IF_ASH_ALIAS(case PEOA:)
continue;
case '#':
while ((c = pgetc()) != '\n' && c != PEOF)
continue;
pungetc();
continue;
case '\\':
if (pgetc() == '\n') {
startlinno = ++g_parsefile->linno;
if (doprompt)
setprompt(2);
continue;
}
pungetc();
goto breakloop;
case '\n':
g_parsefile->linno++;
needprompt = doprompt;
RETURN(TNL);
case PEOF:
RETURN(TEOF);
case '&':
if (pgetc() == '&')
RETURN(TAND);
pungetc();
RETURN(TBACKGND);
case '|':
if (pgetc() == '|')
RETURN(TOR);
pungetc();
RETURN(TPIPE);
case ';':
if (pgetc() == ';')
RETURN(TENDCASE);
pungetc();
RETURN(TSEMI);
case '(':
RETURN(TLP);
case ')':
RETURN(TRP);
default:
goto breakloop;
}
}
breakloop:
return readtoken1(c, BASESYNTAX, (char *)NULL, 0);
#undef RETURN
}
#endif /* old xxreadtoken */
static int
readtoken(void)
{
int t;
#if DEBUG
smallint alreadyseen = tokpushback;
#endif
#if ENABLE_ASH_ALIAS
top:
#endif
t = xxreadtoken();
/*
* eat newlines
*/
if (checkkwd & CHKNL) {
while (t == TNL) {
parseheredoc();
t = xxreadtoken();
}
}
if (t != TWORD || quoteflag) {
goto out;
}
/*
* check for keywords
*/
if (checkkwd & CHKKWD) {
const char *const *pp;
pp = findkwd(wordtext);
if (pp) {
lasttoken = t = pp - tokname_array;
TRACE(("keyword '%s' recognized\n", tokname_array[t] + 1));
goto out;
}
}
if (checkkwd & CHKALIAS) {
#if ENABLE_ASH_ALIAS
struct alias *ap;
ap = lookupalias(wordtext, 1);
if (ap != NULL) {
if (*ap->val) {
pushstring(ap->val, ap);
}
goto top;
}
#endif
}
out:
checkkwd = 0;
#if DEBUG
if (!alreadyseen)
TRACE(("token '%s' %s\n", tokname_array[t] + 1, t == TWORD ? wordtext : ""));
else
TRACE(("reread token '%s' %s\n", tokname_array[t] + 1, t == TWORD ? wordtext : ""));
#endif
return t;
}
static char
peektoken(void)
{
int t;
t = readtoken();
tokpushback = 1;
return tokname_array[t][0];
}
/*
* Read and parse a command. Returns NODE_EOF on end of file.
* (NULL is a valid parse tree indicating a blank line.)
*/
static union node *
parsecmd(int interact)
{
int t;
tokpushback = 0;
doprompt = interact;
if (doprompt)
setprompt(doprompt);
needprompt = 0;
t = readtoken();
if (t == TEOF)
return NODE_EOF;
if (t == TNL)
return NULL;
tokpushback = 1;
return list(1);
}
/*
* Input any here documents.
*/
static void
parseheredoc(void)
{
struct heredoc *here;
union node *n;
here = heredoclist;
heredoclist = NULL;
while (here) {
if (needprompt) {
setprompt(2);
}
readtoken1(pgetc(), here->here->type == NHERE? SQSYNTAX : DQSYNTAX,
here->eofmark, here->striptabs);
n = stzalloc(sizeof(struct narg));
n->narg.type = NARG;
/*n->narg.next = NULL; - stzalloc did it */
n->narg.text = wordtext;
n->narg.backquote = backquotelist;
here->here->nhere.doc = n;
here = here->next;
}
}
/*
* called by editline -- any expansions to the prompt should be added here.
*/
#if ENABLE_ASH_EXPAND_PRMT
static const char *
expandstr(const char *ps)
{
union node n;
/* XXX Fix (char *) cast. It _is_ a bug. ps is variable's value,
* and token processing _can_ alter it (delete NULs etc). */
setinputstring((char *)ps);
readtoken1(pgetc(), PSSYNTAX, nullstr, 0);
popfile();
n.narg.type = NARG;
n.narg.next = NULL;
n.narg.text = wordtext;
n.narg.backquote = backquotelist;
expandarg(&n, NULL, 0);
return stackblock();
}
#endif
/*
* Execute a command or commands contained in a string.
*/
static int
evalstring(char *s, int mask)
{
union node *n;
struct stackmark smark;
int skip;
setinputstring(s);
setstackmark(&smark);
skip = 0;
while ((n = parsecmd(0)) != NODE_EOF) {
evaltree(n, 0);
popstackmark(&smark);
skip = evalskip;
if (skip)
break;
}
popfile();
skip &= mask;
evalskip = skip;
return skip;
}
/*
* The eval command.
*/
static int FAST_FUNC
evalcmd(int argc UNUSED_PARAM, char **argv)
{
char *p;
char *concat;
if (argv[1]) {
p = argv[1];
argv += 2;
if (argv[0]) {
STARTSTACKSTR(concat);
for (;;) {
concat = stack_putstr(p, concat);
p = *argv++;
if (p == NULL)
break;
STPUTC(' ', concat);
}
STPUTC('\0', concat);
p = grabstackstr(concat);
}
evalstring(p, ~SKIPEVAL);
}
return exitstatus;
}
/*
* Read and execute commands.
* "Top" is nonzero for the top level command loop;
* it turns on prompting if the shell is interactive.
*/
static int
cmdloop(int top)
{
union node *n;
struct stackmark smark;
int inter;
int numeof = 0;
TRACE(("cmdloop(%d) called\n", top));
for (;;) {
int skip;
setstackmark(&smark);
#if JOBS
if (doing_jobctl)
showjobs(stderr, SHOW_CHANGED);
#endif
inter = 0;
if (iflag && top) {
inter++;
#if ENABLE_ASH_MAIL
chkmail();
#endif
}
n = parsecmd(inter);
#if DEBUG
if (DEBUG > 2 && debug && (n != NODE_EOF))
showtree(n);
#endif
if (n == NODE_EOF) {
if (!top || numeof >= 50)
break;
if (!stoppedjobs()) {
if (!Iflag)
break;
out2str("\nUse \"exit\" to leave shell.\n");
}
numeof++;
} else if (nflag == 0) {
/* job_warning can only be 2,1,0. Here 2->1, 1/0->0 */
job_warning >>= 1;
numeof = 0;
evaltree(n, 0);
}
popstackmark(&smark);
skip = evalskip;
if (skip) {
evalskip = 0;
return skip & SKIPEVAL;
}
}
return 0;
}
/*
* Take commands from a file. To be compatible we should do a path
* search for the file, which is necessary to find sub-commands.
*/
static char *
find_dot_file(char *name)
{
char *fullname;
const char *path = pathval();
struct stat statb;
/* don't try this for absolute or relative paths */
if (strchr(name, '/'))
return name;
/* IIRC standards do not say whether . is to be searched.
* And it is even smaller this way, making it unconditional for now:
*/
if (1) { /* ENABLE_ASH_BASH_COMPAT */
fullname = name;
goto try_cur_dir;
}
while ((fullname = path_advance(&path, name)) != NULL) {
try_cur_dir:
if ((stat(fullname, &statb) == 0) && S_ISREG(statb.st_mode)) {
/*
* Don't bother freeing here, since it will
* be freed by the caller.
*/
return fullname;
}
if (fullname != name)
stunalloc(fullname);
}
/* not found in the PATH */
ash_msg_and_raise_error("%s: not found", name);
/* NOTREACHED */
}
static int FAST_FUNC
dotcmd(int argc, char **argv)
{
char *fullname;
struct strlist *sp;
volatile struct shparam saveparam;
for (sp = cmdenviron; sp; sp = sp->next)
setvareq(ckstrdup(sp->text), VSTRFIXED | VTEXTFIXED);
if (!argv[1]) {
/* bash says: "bash: .: filename argument required" */
return 2; /* bash compat */
}
/* "false; . empty_file; echo $?" should print 0, not 1: */
exitstatus = 0;
fullname = find_dot_file(argv[1]);
argv += 2;
argc -= 2;
if (argc) { /* argc > 0, argv[0] != NULL */
saveparam = shellparam;
shellparam.malloced = 0;
shellparam.nparam = argc;
shellparam.p = argv;
};
setinputfile(fullname, INPUT_PUSH_FILE);
commandname = fullname;
cmdloop(0);
popfile();
if (argc) {
freeparam(&shellparam);
shellparam = saveparam;
};
return exitstatus;
}
static int FAST_FUNC
exitcmd(int argc UNUSED_PARAM, char **argv)
{
if (stoppedjobs())
return 0;
if (argv[1])
exitstatus = number(argv[1]);
raise_exception(EXEXIT);
/* NOTREACHED */
}
/*
* Read a file containing shell functions.
*/
static void
readcmdfile(char *name)
{
setinputfile(name, INPUT_PUSH_FILE);
cmdloop(0);
popfile();
}
/* ============ find_command inplementation */
/*
* Resolve a command name. If you change this routine, you may have to
* change the shellexec routine as well.
*/
static void
find_command(char *name, struct cmdentry *entry, int act, const char *path)
{
struct tblentry *cmdp;
int idx;
int prev;
char *fullname;
struct stat statb;
int e;
int updatetbl;
struct builtincmd *bcmd;
/* If name contains a slash, don't use PATH or hash table */
if (strchr(name, '/') != NULL) {
entry->u.index = -1;
if (act & DO_ABS) {
while (stat(name, &statb) < 0) {
#ifdef SYSV
if (errno == EINTR)
continue;
#endif
entry->cmdtype = CMDUNKNOWN;
return;
}
}
entry->cmdtype = CMDNORMAL;
return;
}
/* #if ENABLE_FEATURE_SH_STANDALONE... moved after builtin check */
updatetbl = (path == pathval());
if (!updatetbl) {
act |= DO_ALTPATH;
if (strstr(path, "%builtin") != NULL)
act |= DO_ALTBLTIN;
}
/* If name is in the table, check answer will be ok */
cmdp = cmdlookup(name, 0);
if (cmdp != NULL) {
int bit;
switch (cmdp->cmdtype) {
default:
#if DEBUG
abort();
#endif
case CMDNORMAL:
bit = DO_ALTPATH;
break;
case CMDFUNCTION:
bit = DO_NOFUNC;
break;
case CMDBUILTIN:
bit = DO_ALTBLTIN;
break;
}
if (act & bit) {
updatetbl = 0;
cmdp = NULL;
} else if (cmdp->rehash == 0)
/* if not invalidated by cd, we're done */
goto success;
}
/* If %builtin not in path, check for builtin next */
bcmd = find_builtin(name);
if (bcmd) {
if (IS_BUILTIN_REGULAR(bcmd))
goto builtin_success;
if (act & DO_ALTPATH) {
if (!(act & DO_ALTBLTIN))
goto builtin_success;
} else if (builtinloc <= 0) {
goto builtin_success;
}
}
#if ENABLE_FEATURE_SH_STANDALONE
{
int applet_no = find_applet_by_name(name);
if (applet_no >= 0) {
entry->cmdtype = CMDNORMAL;
entry->u.index = -2 - applet_no;
return;
}
}
#endif
/* We have to search path. */
prev = -1; /* where to start */
if (cmdp && cmdp->rehash) { /* doing a rehash */
if (cmdp->cmdtype == CMDBUILTIN)
prev = builtinloc;
else
prev = cmdp->param.index;
}
e = ENOENT;
idx = -1;
loop:
while ((fullname = path_advance(&path, name)) != NULL) {
stunalloc(fullname);
/* NB: code below will still use fullname
* despite it being "unallocated" */
idx++;
if (pathopt) {
if (prefix(pathopt, "builtin")) {
if (bcmd)
goto builtin_success;
continue;
}
if ((act & DO_NOFUNC)
|| !prefix(pathopt, "func")
) { /* ignore unimplemented options */
continue;
}
}
/* if rehash, don't redo absolute path names */
if (fullname[0] == '/' && idx <= prev) {
if (idx < prev)
continue;
TRACE(("searchexec \"%s\": no change\n", name));
goto success;
}
while (stat(fullname, &statb) < 0) {
#ifdef SYSV
if (errno == EINTR)
continue;
#endif
if (errno != ENOENT && errno != ENOTDIR)
e = errno;
goto loop;
}
e = EACCES; /* if we fail, this will be the error */
if (!S_ISREG(statb.st_mode))
continue;
if (pathopt) { /* this is a %func directory */
stalloc(strlen(fullname) + 1);
/* NB: stalloc will return space pointed by fullname
* (because we don't have any intervening allocations
* between stunalloc above and this stalloc) */
readcmdfile(fullname);
cmdp = cmdlookup(name, 0);
if (cmdp == NULL || cmdp->cmdtype != CMDFUNCTION)
ash_msg_and_raise_error("%s not defined in %s", name, fullname);
stunalloc(fullname);
goto success;
}
TRACE(("searchexec \"%s\" returns \"%s\"\n", name, fullname));
if (!updatetbl) {
entry->cmdtype = CMDNORMAL;
entry->u.index = idx;
return;
}
INT_OFF;
cmdp = cmdlookup(name, 1);
cmdp->cmdtype = CMDNORMAL;
cmdp->param.index = idx;
INT_ON;
goto success;
}
/* We failed. If there was an entry for this command, delete it */
if (cmdp && updatetbl)
delete_cmd_entry();
if (act & DO_ERR)
ash_msg("%s: %s", name, errmsg(e, "not found"));
entry->cmdtype = CMDUNKNOWN;
return;
builtin_success:
if (!updatetbl) {
entry->cmdtype = CMDBUILTIN;
entry->u.cmd = bcmd;
return;
}
INT_OFF;
cmdp = cmdlookup(name, 1);
cmdp->cmdtype = CMDBUILTIN;
cmdp->param.cmd = bcmd;
INT_ON;
success:
cmdp->rehash = 0;
entry->cmdtype = cmdp->cmdtype;
entry->u = cmdp->param;
}
/* ============ trap.c */
/*
* The trap builtin.
*/
static int FAST_FUNC
trapcmd(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
{
char *action;
char **ap;
int signo, exitcode;
nextopt(nullstr);
ap = argptr;
if (!*ap) {
for (signo = 0; signo < NSIG; signo++) {
char *tr = trap_ptr[signo];
if (tr) {
/* note: bash adds "SIG", but only if invoked
* as "bash". If called as "sh", or if set -o posix,
* then it prints short signal names.
* We are printing short names: */
out1fmt("trap -- %s %s\n",
single_quote(tr),
get_signame(signo));
/* trap_ptr != trap only if we are in special-cased `trap` code.
* In this case, we will exit very soon, no need to free(). */
/* if (trap_ptr != trap && tp[0]) */
/* free(tr); */
}
}
/*
if (trap_ptr != trap) {
free(trap_ptr);
trap_ptr = trap;
}
*/
return 0;
}
action = NULL;
if (ap[1])
action = *ap++;
exitcode = 0;
while (*ap) {
signo = get_signum(*ap);
if (signo < 0) {
/* Mimic bash message exactly */
ash_msg("%s: invalid signal specification", *ap);
exitcode = 1;
goto next;
}
INT_OFF;
if (action) {
if (LONE_DASH(action))
action = NULL;
else
action = ckstrdup(action);
}
free(trap[signo]);
if (action)
may_have_traps = 1;
trap[signo] = action;
if (signo != 0)
setsignal(signo);
INT_ON;
next:
ap++;
}
return exitcode;
}
/* ============ Builtins */
#if !ENABLE_FEATURE_SH_EXTRA_QUIET
/*
* Lists available builtins
*/
static int FAST_FUNC
helpcmd(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
{
unsigned col;
unsigned i;
out1fmt(
"Built-in commands:\n"
"------------------\n");
for (col = 0, i = 0; i < ARRAY_SIZE(builtintab); i++) {
col += out1fmt("%c%s", ((col == 0) ? '\t' : ' '),
builtintab[i].name + 1);
if (col > 60) {
out1fmt("\n");
col = 0;
}
}
#if ENABLE_FEATURE_SH_STANDALONE
{
const char *a = applet_names;
while (*a) {
col += out1fmt("%c%s", ((col == 0) ? '\t' : ' '), a);
if (col > 60) {
out1fmt("\n");
col = 0;
}
a += strlen(a) + 1;
}
}
#endif
out1fmt("\n\n");
return EXIT_SUCCESS;
}
#endif /* FEATURE_SH_EXTRA_QUIET */
/*
* The export and readonly commands.
*/
static int FAST_FUNC
exportcmd(int argc UNUSED_PARAM, char **argv)
{
struct var *vp;
char *name;
const char *p;
char **aptr;
int flag = argv[0][0] == 'r' ? VREADONLY : VEXPORT;
if (nextopt("p") != 'p') {
aptr = argptr;
name = *aptr;
if (name) {
do {
p = strchr(name, '=');
if (p != NULL) {
p++;
} else {
vp = *findvar(hashvar(name), name);
if (vp) {
vp->flags |= flag;
continue;
}
}
setvar(name, p, flag);
} while ((name = *++aptr) != NULL);
return 0;
}
}
showvars(argv[0], flag, 0);
return 0;
}
/*
* Delete a function if it exists.
*/
static void
unsetfunc(const char *name)
{
struct tblentry *cmdp;
cmdp = cmdlookup(name, 0);
if (cmdp!= NULL && cmdp->cmdtype == CMDFUNCTION)
delete_cmd_entry();
}
/*
* The unset builtin command. We unset the function before we unset the
* variable to allow a function to be unset when there is a readonly variable
* with the same name.
*/
static int FAST_FUNC
unsetcmd(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
{
char **ap;
int i;
int flag = 0;
int ret = 0;
while ((i = nextopt("vf")) != '\0') {
flag = i;
}
for (ap = argptr; *ap; ap++) {
if (flag != 'f') {
i = unsetvar(*ap);
ret |= i;
if (!(i & 2))
continue;
}
if (flag != 'v')
unsetfunc(*ap);
}
return ret & 1;
}
/* setmode.c */
#include <sys/times.h>
static const unsigned char timescmd_str[] ALIGN1 = {
' ', offsetof(struct tms, tms_utime),
'\n', offsetof(struct tms, tms_stime),
' ', offsetof(struct tms, tms_cutime),
'\n', offsetof(struct tms, tms_cstime),
0
};
static int FAST_FUNC
timescmd(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
{
long clk_tck, s, t;
const unsigned char *p;
struct tms buf;
clk_tck = sysconf(_SC_CLK_TCK);
times(&buf);
p = timescmd_str;
do {
t = *(clock_t *)(((char *) &buf) + p[1]);
s = t / clk_tck;
out1fmt("%ldm%ld.%.3lds%c",
s/60, s%60,
((t - s * clk_tck) * 1000) / clk_tck,
p[0]);
} while (*(p += 2));
return 0;
}
#if ENABLE_SH_MATH_SUPPORT
/*
* The let builtin. partial stolen from GNU Bash, the Bourne Again SHell.
* Copyright (C) 1987, 1989, 1991 Free Software Foundation, Inc.
*
* Copyright (C) 2003 Vladimir Oleynik <dzo@simtreas.ru>
*/
static int FAST_FUNC
letcmd(int argc UNUSED_PARAM, char **argv)
{
arith_t i;
argv++;
if (!*argv)
ash_msg_and_raise_error("expression expected");
do {
i = ash_arith(*argv);
} while (*++argv);
return !i;
}
#endif /* SH_MATH_SUPPORT */
/* ============ miscbltin.c
*
* Miscellaneous builtins.
*/
#undef rflag
#if defined(__GLIBC__) && __GLIBC__ == 2 && __GLIBC_MINOR__ < 1
typedef enum __rlimit_resource rlim_t;
#endif
/*
* The read builtin. Options:
* -r Do not interpret '\' specially
* -s Turn off echo (tty only)
* -n NCHARS Read NCHARS max
* -p PROMPT Display PROMPT on stderr (if input is from tty)
* -t SECONDS Timeout after SECONDS (tty or pipe only)
* -u FD Read from given FD instead of fd 0
* This uses unbuffered input, which may be avoidable in some cases.
* TODO: bash also has:
* -a ARRAY Read into array[0],[1],etc
* -d DELIM End on DELIM char, not newline
* -e Use line editing (tty only)
*/
static int FAST_FUNC
readcmd(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
{
char *opt_n = NULL;
char *opt_p = NULL;
char *opt_t = NULL;
char *opt_u = NULL;
int read_flags = 0;
const char *r;
int i;
while ((i = nextopt("p:u:rt:n:s")) != '\0') {
switch (i) {
case 'p':
opt_p = optionarg;
break;
case 'n':
opt_n = optionarg;
break;
case 's':
read_flags |= BUILTIN_READ_SILENT;
break;
case 't':
opt_t = optionarg;
break;
case 'r':
read_flags |= BUILTIN_READ_RAW;
break;
case 'u':
opt_u = optionarg;
break;
default:
break;
}
}
r = shell_builtin_read(setvar2,
argptr,
bltinlookup("IFS"), /* can be NULL */
read_flags,
opt_n,
opt_p,
opt_t,
opt_u
);
if ((uintptr_t)r > 1)
ash_msg_and_raise_error(r);
return (uintptr_t)r;
}
static int FAST_FUNC
umaskcmd(int argc UNUSED_PARAM, char **argv)
{
static const char permuser[3] ALIGN1 = "ugo";
static const char permmode[3] ALIGN1 = "rwx";
static const short permmask[] ALIGN2 = {
S_IRUSR, S_IWUSR, S_IXUSR,
S_IRGRP, S_IWGRP, S_IXGRP,
S_IROTH, S_IWOTH, S_IXOTH
};
/* TODO: use bb_parse_mode() instead */
char *ap;
mode_t mask;
int i;
int symbolic_mode = 0;
while (nextopt("S") != '\0') {
symbolic_mode = 1;
}
INT_OFF;
mask = umask(0);
umask(mask);
INT_ON;
ap = *argptr;
if (ap == NULL) {
if (symbolic_mode) {
char buf[18];
char *p = buf;
for (i = 0; i < 3; i++) {
int j;
*p++ = permuser[i];
*p++ = '=';
for (j = 0; j < 3; j++) {
if ((mask & permmask[3 * i + j]) == 0) {
*p++ = permmode[j];
}
}
*p++ = ',';
}
*--p = 0;
puts(buf);
} else {
out1fmt("%.4o\n", mask);
}
} else {
if (isdigit((unsigned char) *ap)) {
mask = 0;
do {
if (*ap >= '8' || *ap < '0')
ash_msg_and_raise_error(msg_illnum, argv[1]);
mask = (mask << 3) + (*ap - '0');
} while (*++ap != '\0');
umask(mask);
} else {
mask = ~mask & 0777;
if (!bb_parse_mode(ap, &mask)) {
ash_msg_and_raise_error("illegal mode: %s", ap);
}
umask(~mask & 0777);
}
}
return 0;
}
static int FAST_FUNC
ulimitcmd(int argc UNUSED_PARAM, char **argv)
{
return shell_builtin_ulimit(argv);
}
/* ============ main() and helpers */
/*
* Called to exit the shell.
*/
static void exitshell(void) NORETURN;
static void
exitshell(void)
{
struct jmploc loc;
char *p;
int status;
status = exitstatus;
TRACE(("pid %d, exitshell(%d)\n", getpid(), status));
if (setjmp(loc.loc)) {
if (exception_type == EXEXIT)
/* dash bug: it just does _exit(exitstatus) here
* but we have to do setjobctl(0) first!
* (bug is still not fixed in dash-0.5.3 - if you run dash
* under Midnight Commander, on exit from dash MC is backgrounded) */
status = exitstatus;
goto out;
}
exception_handler = &loc;
p = trap[0];
if (p) {
trap[0] = NULL;
evalstring(p, 0);
free(p);
}
flush_stdout_stderr();
out:
setjobctl(0);
_exit(status);
/* NOTREACHED */
}
static void
init(void)
{
/* from input.c: */
/* we will never free this */
basepf.next_to_pgetc = basepf.buf = ckmalloc(IBUFSIZ);
/* from trap.c: */
signal(SIGCHLD, SIG_DFL);
/* bash re-enables SIGHUP which is SIG_IGNed on entry.
* Try: "trap '' HUP; bash; echo RET" and type "kill -HUP $$"
*/
signal(SIGHUP, SIG_DFL);
/* from var.c: */
{
char **envp;
const char *p;
struct stat st1, st2;
initvar();
for (envp = environ; envp && *envp; envp++) {
if (strchr(*envp, '=')) {
setvareq(*envp, VEXPORT|VTEXTFIXED);
}
}
setvar("PPID", utoa(getppid()), 0);
p = lookupvar("PWD");
if (p)
if (*p != '/' || stat(p, &st1) || stat(".", &st2)
|| st1.st_dev != st2.st_dev || st1.st_ino != st2.st_ino)
p = '\0';
setpwd(p, 0);
}
}
/*
* Process the shell command line arguments.
*/
static void
procargs(char **argv)
{
int i;
const char *xminusc;
char **xargv;
xargv = argv;
arg0 = xargv[0];
/* if (xargv[0]) - mmm, this is always true! */
xargv++;
for (i = 0; i < NOPTS; i++)
optlist[i] = 2;
argptr = xargv;
if (options(1)) {
/* it already printed err message */
raise_exception(EXERROR);
}
xargv = argptr;
xminusc = minusc;
if (*xargv == NULL) {
if (xminusc)
ash_msg_and_raise_error(bb_msg_requires_arg, "-c");
sflag = 1;
}
if (iflag == 2 && sflag == 1 && isatty(0) && isatty(1))
iflag = 1;
if (mflag == 2)
mflag = iflag;
for (i = 0; i < NOPTS; i++)
if (optlist[i] == 2)
optlist[i] = 0;
#if DEBUG == 2
debug = 1;
#endif
/* POSIX 1003.2: first arg after -c cmd is $0, remainder $1... */
if (xminusc) {
minusc = *xargv++;
if (*xargv)
goto setarg0;
} else if (!sflag) {
setinputfile(*xargv, 0);
setarg0:
arg0 = *xargv++;
commandname = arg0;
}
shellparam.p = xargv;
#if ENABLE_ASH_GETOPTS
shellparam.optind = 1;
shellparam.optoff = -1;
#endif
/* assert(shellparam.malloced == 0 && shellparam.nparam == 0); */
while (*xargv) {
shellparam.nparam++;
xargv++;
}
optschanged();
}
/*
* Read /etc/profile or .profile.
*/
static void
read_profile(const char *name)
{
int skip;
if (setinputfile(name, INPUT_PUSH_FILE | INPUT_NOFILE_OK) < 0)
return;
skip = cmdloop(0);
popfile();
if (skip)
exitshell();
}
/*
* This routine is called when an error or an interrupt occurs in an
* interactive shell and control is returned to the main command loop.
*/
static void
reset(void)
{
/* from eval.c: */
evalskip = 0;
loopnest = 0;
/* from input.c: */
g_parsefile->left_in_buffer = 0;
g_parsefile->left_in_line = 0; /* clear input buffer */
popallfiles();
/* from parser.c: */
tokpushback = 0;
checkkwd = 0;
/* from redir.c: */
clearredir(/*drop:*/ 0);
}
#if PROFILE
static short profile_buf[16384];
extern int etext();
#endif
/*
* Main routine. We initialize things, parse the arguments, execute
* profiles if we're a login shell, and then call cmdloop to execute
* commands. The setjmp call sets up the location to jump to when an
* exception occurs. When an exception occurs the variable "state"
* is used to figure out how far we had gotten.
*/
int ash_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int ash_main(int argc UNUSED_PARAM, char **argv)
{
const char *shinit;
volatile smallint state;
struct jmploc jmploc;
struct stackmark smark;
/* Initialize global data */
INIT_G_misc();
INIT_G_memstack();
INIT_G_var();
#if ENABLE_ASH_ALIAS
INIT_G_alias();
#endif
INIT_G_cmdtable();
#if PROFILE
monitor(4, etext, profile_buf, sizeof(profile_buf), 50);
#endif
#if ENABLE_FEATURE_EDITING
line_input_state = new_line_input_t(FOR_SHELL | WITH_PATH_LOOKUP);
#endif
state = 0;
if (setjmp(jmploc.loc)) {
smallint e;
smallint s;
reset();
e = exception_type;
if (e == EXERROR)
exitstatus = 2;
s = state;
if (e == EXEXIT || s == 0 || iflag == 0 || shlvl)
exitshell();
if (e == EXINT)
outcslow('\n', stderr);
popstackmark(&smark);
FORCE_INT_ON; /* enable interrupts */
if (s == 1)
goto state1;
if (s == 2)
goto state2;
if (s == 3)
goto state3;
goto state4;
}
exception_handler = &jmploc;
#if DEBUG
opentrace();
TRACE(("Shell args: "));
trace_puts_args(argv);
#endif
rootpid = getpid();
init();
setstackmark(&smark);
procargs(argv);
#if ENABLE_FEATURE_EDITING_SAVEHISTORY
if (iflag) {
const char *hp = lookupvar("HISTFILE");
if (hp == NULL) {
hp = lookupvar("HOME");
if (hp != NULL) {
char *defhp = concat_path_file(hp, ".ash_history");
setvar("HISTFILE", defhp, 0);
free(defhp);
}
}
}
#endif
if (/* argv[0] && */ argv[0][0] == '-')
isloginsh = 1;
if (isloginsh) {
state = 1;
read_profile("/etc/profile");
state1:
state = 2;
read_profile(".profile");
}
state2:
state = 3;
if (
#ifndef linux
getuid() == geteuid() && getgid() == getegid() &&
#endif
iflag
) {
shinit = lookupvar("ENV");
if (shinit != NULL && *shinit != '\0') {
read_profile(shinit);
}
}
state3:
state = 4;
if (minusc) {
/* evalstring pushes parsefile stack.
* Ensure we don't falsely claim that 0 (stdin)
* is one of stacked source fds.
* Testcase: ash -c 'exec 1>&0' must not complain. */
if (!sflag)
g_parsefile->fd = -1;
evalstring(minusc, 0);
}
if (sflag || minusc == NULL) {
#if defined MAX_HISTORY && MAX_HISTORY > 0 && ENABLE_FEATURE_EDITING_SAVEHISTORY
if (iflag) {
const char *hp = lookupvar("HISTFILE");
if (hp)
line_input_state->hist_file = hp;
}
#endif
state4: /* XXX ??? - why isn't this before the "if" statement */
cmdloop(1);
}
#if PROFILE
monitor(0);
#endif
#ifdef GPROF
{
extern void _mcleanup(void);
_mcleanup();
}
#endif
exitshell();
/* NOTREACHED */
}
/*-
* Copyright (c) 1989, 1991, 1993, 1994
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Kenneth Almquist.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
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