mirror of
https://github.com/topjohnwu/ndk-busybox.git
synced 2024-12-14 23:38:35 +00:00
340 lines
6.8 KiB
C
340 lines
6.8 KiB
C
/* vi: set sw=4 ts=4: */
|
|
/* tail -- output the last part of file(s)
|
|
Copyright (C) 89, 90, 91, 95, 1996 Free Software Foundation, Inc.
|
|
|
|
This program is free software; you can redistribute it and/or modify
|
|
it under the terms of the GNU General Public License as published by
|
|
the Free Software Foundation; either version 2, or (at your option)
|
|
any later version.
|
|
|
|
This program is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
GNU General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with this program; if not, write to the Free Software
|
|
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
|
|
|
|
Original version by Paul Rubin <phr@ocf.berkeley.edu>.
|
|
Extensions by David MacKenzie <djm@gnu.ai.mit.edu>.
|
|
tail -f for multiple files by Ian Lance Taylor <ian@airs.com>.
|
|
|
|
Rewrote the option parser, removed locales support,
|
|
and generally busyboxed, Erik Andersen <andersen@lineo.com>
|
|
|
|
Removed superfluous options and associated code ("-c", "-n", "-q").
|
|
Removed "tail -f" support for multiple files.
|
|
Both changes by Friedrich Vedder <fwv@myrtle.lahn.de>.
|
|
|
|
Compleate Rewrite to correctly support "-NUM", "+NUM", and "-s" by
|
|
E.Allen Soard (esp@espsw.net).
|
|
|
|
*/
|
|
#include <sys/types.h>
|
|
#include <fcntl.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <unistd.h>
|
|
#include <string.h>
|
|
#include <getopt.h>
|
|
#include "internal.h"
|
|
|
|
#define STDIN "standard input"
|
|
#define LINES 0
|
|
#define BYTES 1
|
|
|
|
static int n_files = 0;
|
|
static char **files = NULL;
|
|
static char * buffer;
|
|
static ssize_t bytes_read=0;
|
|
static ssize_t bs;
|
|
static ssize_t filelocation=0;
|
|
static char pip;
|
|
|
|
#ifdef BB_FEATURE_SIMPLE_TAIL
|
|
static const char unit_type=LINES;
|
|
#else
|
|
static char unit_type=LINES;
|
|
static char verbose = 0;
|
|
#endif
|
|
|
|
static off_t units=0;
|
|
|
|
int tail_stream(int fd)
|
|
{
|
|
ssize_t startpoint;
|
|
ssize_t endpoint=0;
|
|
ssize_t count=0;
|
|
ssize_t filesize=0;
|
|
char direction=1;
|
|
|
|
filelocation=0;
|
|
startpoint=bs=BUFSIZ;
|
|
|
|
filesize=lseek(fd, -1, SEEK_END)+1;
|
|
pip=(filesize<=0);
|
|
|
|
if(units>=0)
|
|
lseek(fd,0,SEEK_SET);
|
|
else {
|
|
direction=-1;
|
|
count=1;
|
|
}
|
|
while(units != 0) {
|
|
if (pip) {
|
|
char * line;
|
|
ssize_t f_size=0;
|
|
|
|
bs=BUFSIZ;
|
|
line=malloc(bs);
|
|
while(1) {
|
|
bytes_read=read(fd,line,bs);
|
|
if(bytes_read<=0)
|
|
break;
|
|
buffer=realloc(buffer,f_size+bytes_read);
|
|
memcpy(&buffer[f_size],line,bytes_read);
|
|
filelocation=f_size+=bytes_read;
|
|
}
|
|
bs=f_size;
|
|
if(direction<0)
|
|
bs--;
|
|
if (line)
|
|
free(line);
|
|
} else {
|
|
filelocation = lseek(fd, 0, SEEK_CUR);
|
|
if(direction<0) {
|
|
if(filelocation<bs)
|
|
bs=filelocation;
|
|
filelocation = lseek(fd, -bs, SEEK_CUR);
|
|
}
|
|
bytes_read = read(fd, buffer, bs);
|
|
if (bytes_read <= 0)
|
|
break;
|
|
bs=bytes_read;
|
|
}
|
|
startpoint=bs;
|
|
if(direction>0) {
|
|
endpoint=startpoint;
|
|
startpoint=0;
|
|
}
|
|
for(;startpoint!=endpoint;startpoint+=direction) {
|
|
#ifndef BB_FEATURE_SIMPLE_TAIL
|
|
if(unit_type==BYTES)
|
|
count++;
|
|
else
|
|
#endif
|
|
if(buffer[startpoint-1]=='\n')
|
|
count++;
|
|
if (!pip)
|
|
filelocation=lseek(fd,0,SEEK_CUR);
|
|
if(count==units*direction)
|
|
break;
|
|
}
|
|
if((count==units*direction) | pip)
|
|
break;
|
|
if(direction<0){
|
|
filelocation = lseek(fd, -bytes_read, SEEK_CUR);
|
|
if(filelocation==0)
|
|
break;
|
|
}
|
|
}
|
|
if(pip && (direction<0))
|
|
bs++;
|
|
bytes_read=bs-startpoint;
|
|
memcpy(&buffer[0],&buffer[startpoint],bytes_read);
|
|
|
|
return 0;
|
|
}
|
|
|
|
void add_file(char *name)
|
|
{
|
|
++n_files;
|
|
files = realloc(files, n_files);
|
|
files[n_files - 1] = (char *) malloc(strlen(name) + 1);
|
|
strcpy(files[n_files - 1], name);
|
|
}
|
|
|
|
void checknumbers(const char* name)
|
|
{
|
|
int test=atoi(name);
|
|
if(test){
|
|
units=test;
|
|
if(units<0)
|
|
units=units-1;
|
|
} else {
|
|
fatalError("Unrecognised number '%s'\n", name);
|
|
}
|
|
}
|
|
|
|
int tail_main(int argc, char **argv)
|
|
{
|
|
int show_headers = 1;
|
|
int test;
|
|
int opt;
|
|
char follow=0;
|
|
int sleep_int=1;
|
|
int *fd;
|
|
|
|
opterr = 0;
|
|
|
|
while ((opt=getopt(argc,argv,"c:fhn:s:q:v123456789+")) >0) {
|
|
|
|
switch (opt) {
|
|
case '1':case '2':case '3':case '4':case '5':
|
|
case '6':case '7':case '8':case '9':case '0':
|
|
checknumbers(argv[optind-1]);
|
|
break;
|
|
|
|
#ifndef BB_FEATURE_SIMPLE_TAIL
|
|
case 'c':
|
|
unit_type = BYTES;
|
|
test = atoi(optarg);
|
|
if(test==0)
|
|
usage(tail_usage);
|
|
if(optarg[strlen(optarg)-1]>'9') {
|
|
switch (optarg[strlen(optarg)-1]) {
|
|
case 'b':
|
|
test *= 512;
|
|
break;
|
|
case 'k':
|
|
test *= 1024;
|
|
break;
|
|
case 'm':
|
|
test *= (1024 * 1024);
|
|
break;
|
|
default:
|
|
fprintf(stderr,"Size must be b,k, or m.");
|
|
usage(tail_usage);
|
|
}
|
|
}
|
|
if(optarg[0]=='+')
|
|
units=test+1;
|
|
else
|
|
units=-(test+1);
|
|
break;
|
|
case 'q':
|
|
show_headers = 0;
|
|
break;
|
|
case 's':
|
|
sleep_int = atoi(optarg);
|
|
if(sleep_int<1)
|
|
sleep_int=1;
|
|
break;
|
|
case 'v':
|
|
verbose = 1;
|
|
break;
|
|
#endif
|
|
case 'f':
|
|
follow = 1;
|
|
break;
|
|
case 'h':
|
|
usage(tail_usage);
|
|
break;
|
|
case 'n':
|
|
test = atoi(optarg);
|
|
if (test) {
|
|
if (optarg[0] == '+')
|
|
units = test;
|
|
else
|
|
units = -(test+1);
|
|
} else
|
|
usage(tail_usage);
|
|
break;
|
|
default:
|
|
errorMsg("\nUnknown arg: %c.\n\n",optopt);
|
|
usage(tail_usage);
|
|
}
|
|
}
|
|
while (optind <= argc) {
|
|
if(optind==argc) {
|
|
if (n_files==0)
|
|
add_file(STDIN);
|
|
else
|
|
break;
|
|
}else {
|
|
if (*argv[optind] == '+') {
|
|
checknumbers(argv[optind]);
|
|
}
|
|
else if (!strcmp(argv[optind], "-")) {
|
|
add_file(STDIN);
|
|
} else {
|
|
add_file(argv[optind]);
|
|
}
|
|
optind++;
|
|
}
|
|
}
|
|
if(units==0)
|
|
units=-11;
|
|
if(units>0)
|
|
units--;
|
|
fd=malloc(sizeof(int)*n_files);
|
|
if (n_files == 1)
|
|
#ifndef BB_FEATURE_SIMPLE_TAIL
|
|
if (!verbose)
|
|
#endif
|
|
show_headers = 0;
|
|
buffer=malloc(BUFSIZ);
|
|
for (test = 0; test < n_files; test++) {
|
|
if (show_headers)
|
|
printf("==> %s <==\n", files[test]);
|
|
if (!strcmp(files[test], STDIN))
|
|
fd[test] = 0;
|
|
else
|
|
fd[test] = open(files[test], O_RDONLY);
|
|
if (fd[test] == -1)
|
|
fatalError("Unable to open file %s.\n", files[test]);
|
|
tail_stream(fd[test]);
|
|
|
|
bs=BUFSIZ;
|
|
while (1) {
|
|
if((filelocation>0 || pip)){
|
|
write(1,buffer,bytes_read);
|
|
}
|
|
bytes_read = read(fd[test], buffer, bs);
|
|
filelocation+=bytes_read;
|
|
if (bytes_read <= 0) {
|
|
break;
|
|
}
|
|
usleep(sleep_int * 1000);
|
|
}
|
|
if(n_files>1)
|
|
printf("\n");
|
|
}
|
|
while(1){
|
|
for (test = 0; test < n_files; test++) {
|
|
if(!follow){
|
|
close(fd[test]);
|
|
continue;
|
|
} else {
|
|
sleep(sleep_int);
|
|
bytes_read = read(fd[test], buffer, bs);
|
|
if(bytes_read>0) {
|
|
if (show_headers)
|
|
printf("==> %s <==\n", files[test]);
|
|
write(1,buffer,bytes_read);
|
|
if(n_files>1)
|
|
printf("\n");
|
|
}
|
|
}
|
|
}
|
|
if(!follow)
|
|
break;
|
|
}
|
|
if (fd)
|
|
free(fd);
|
|
if (buffer)
|
|
free(buffer);
|
|
if(files)
|
|
free(files);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
Local Variables:
|
|
c-file-style: "linux"
|
|
c-basic-offset: 4
|
|
tab-width: 4
|
|
End:
|
|
*/
|