mirror of
https://github.com/topjohnwu/ndk-busybox.git
synced 2024-12-04 01:43:11 +00:00
79e2598c48
Also, added a comment about bug 9401 (TIOCSTI input injection). function old new delta packed_usage 30909 30932 +23 su_main 470 487 +17 sulogin_main 260 258 -2 run_applet_and_exit 681 678 -3 run_shell 166 126 -40 Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
102 lines
2.6 KiB
C
102 lines
2.6 KiB
C
/* vi: set sw=4 ts=4: */
|
|
/*
|
|
* Utility routines.
|
|
*
|
|
* Copyright (C) 2006 Gabriel Somlo <somlo at cmu.edu>
|
|
*
|
|
* Licensed under GPLv2 or later, see file LICENSE in this source tree.
|
|
*/
|
|
|
|
#include "libbb.h"
|
|
|
|
/* check if path points to an executable file;
|
|
* return 1 if found;
|
|
* return 0 otherwise;
|
|
*/
|
|
int FAST_FUNC file_is_executable(const char *name)
|
|
{
|
|
struct stat s;
|
|
return (!access(name, X_OK) && !stat(name, &s) && S_ISREG(s.st_mode));
|
|
}
|
|
|
|
/* search (*PATHp) for an executable file;
|
|
* return allocated string containing full path if found;
|
|
* PATHp points to the component after the one where it was found
|
|
* (or NULL),
|
|
* you may call find_executable again with this PATHp to continue
|
|
* (if it's not NULL).
|
|
* return NULL otherwise; (PATHp is undefined)
|
|
* in all cases (*PATHp) contents will be trashed (s/:/NUL/).
|
|
*/
|
|
char* FAST_FUNC find_executable(const char *filename, char **PATHp)
|
|
{
|
|
/* About empty components in $PATH:
|
|
* http://pubs.opengroup.org/onlinepubs/009695399/basedefs/xbd_chap08.html
|
|
* 8.3 Other Environment Variables - PATH
|
|
* A zero-length prefix is a legacy feature that indicates the current
|
|
* working directory. It appears as two adjacent colons ( "::" ), as an
|
|
* initial colon preceding the rest of the list, or as a trailing colon
|
|
* following the rest of the list.
|
|
*/
|
|
char *p, *n;
|
|
|
|
p = *PATHp;
|
|
while (p) {
|
|
n = strchr(p, ':');
|
|
if (n)
|
|
*n++ = '\0';
|
|
p = concat_path_file(
|
|
p[0] ? p : ".", /* handle "::" case */
|
|
filename
|
|
);
|
|
if (file_is_executable(p)) {
|
|
*PATHp = n;
|
|
return p;
|
|
}
|
|
free(p);
|
|
p = n;
|
|
} /* on loop exit p == NULL */
|
|
return p;
|
|
}
|
|
|
|
/* search $PATH for an executable file;
|
|
* return 1 if found;
|
|
* return 0 otherwise;
|
|
*/
|
|
int FAST_FUNC executable_exists(const char *filename)
|
|
{
|
|
char *path = xstrdup(getenv("PATH"));
|
|
char *tmp = path;
|
|
char *ret = find_executable(filename, &tmp);
|
|
free(path);
|
|
free(ret);
|
|
return ret != NULL;
|
|
}
|
|
|
|
#if ENABLE_FEATURE_PREFER_APPLETS
|
|
/* just like the real execvp, but try to launch an applet named 'file' first */
|
|
int FAST_FUNC BB_EXECVP(const char *file, char *const argv[])
|
|
{
|
|
if (find_applet_by_name(file) >= 0)
|
|
execvp(bb_busybox_exec_path, argv);
|
|
return execvp(file, argv);
|
|
}
|
|
#endif
|
|
|
|
void FAST_FUNC BB_EXECVP_or_die(char **argv)
|
|
{
|
|
BB_EXECVP(argv[0], argv);
|
|
/* SUSv3-mandated exit codes */
|
|
xfunc_error_retval = (errno == ENOENT) ? 127 : 126;
|
|
bb_perror_msg_and_die("can't execute '%s'", argv[0]);
|
|
}
|
|
|
|
/* Typical idiom for applets which exec *optional* PROG [ARGS] */
|
|
void FAST_FUNC exec_prog_or_SHELL(char **argv)
|
|
{
|
|
if (argv[0]) {
|
|
BB_EXECVP_or_die(argv);
|
|
}
|
|
run_shell(getenv("SHELL"), /*login:*/ 1, NULL);
|
|
}
|