93 lines
1.9 KiB
C
93 lines
1.9 KiB
C
/* vi: set sw=4 ts=4: */
|
|
/*
|
|
* tac implementation for busybox
|
|
*
|
|
* Copyright (C) 2003 Yang Xiaopeng <yxp at hanwang.com.cn>
|
|
* Copyright (C) 2007 Natanael Copa <natanael.copa@gmail.com>
|
|
* Copyright (C) 2007 Tito Ragusa <farmatito@tiscali.it>
|
|
*
|
|
* Licensed under GPLv2, see file License in this tarball for details.
|
|
*
|
|
*/
|
|
|
|
/* tac - concatenate and print files in reverse */
|
|
|
|
/* Based on Yang Xiaopeng's (yxp at hanwang.com.cn) patch
|
|
* http://www.uclibc.org/lists/busybox/2003-July/008813.html
|
|
*/
|
|
|
|
#include "libbb.h"
|
|
|
|
/* This is a NOEXEC applet. Be very careful! */
|
|
|
|
struct lstring {
|
|
int size;
|
|
char buf[];
|
|
};
|
|
|
|
int tac_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
|
|
int tac_main(int argc, char **argv)
|
|
{
|
|
char **name;
|
|
FILE *f;
|
|
struct lstring *line = NULL;
|
|
llist_t *list = NULL;
|
|
int retval = EXIT_SUCCESS;
|
|
|
|
argv++;
|
|
if (!*argv)
|
|
*--argv = (char *)"-";
|
|
/* We will read from last file to first */
|
|
name = argv;
|
|
while (*name)
|
|
name++;
|
|
|
|
do {
|
|
int ch, i;
|
|
|
|
name--;
|
|
f = fopen_or_warn_stdin(*name);
|
|
if (f == NULL) {
|
|
retval = EXIT_FAILURE;
|
|
continue;
|
|
}
|
|
|
|
errno = i = 0;
|
|
do {
|
|
ch = fgetc(f);
|
|
if (ch != EOF) {
|
|
if (!(i & 0x7f))
|
|
/* Grow on every 128th char */
|
|
line = xrealloc(line, i + 0x7f + sizeof(int) + 1);
|
|
line->buf[i++] = ch;
|
|
}
|
|
if ((ch == '\n' || ch == EOF) && i) {
|
|
line = xrealloc(line, i + sizeof(int));
|
|
line->size = i;
|
|
llist_add_to(&list, line);
|
|
line = NULL;
|
|
i = 0;
|
|
}
|
|
} while (ch != EOF);
|
|
/* fgetc sets errno to ENOENT on EOF, but */
|
|
/* fopen_or_warn_stdin would catch this error */
|
|
/* so we can filter it out here. */
|
|
if (errno && errno != ENOENT) {
|
|
bb_simple_perror_msg(*name);
|
|
retval = EXIT_FAILURE;
|
|
}
|
|
} while (name != argv);
|
|
|
|
while (list) {
|
|
line = (struct lstring *)list->data;
|
|
xwrite(STDOUT_FILENO, line->buf, line->size);
|
|
if (ENABLE_FEATURE_CLEAN_UP) {
|
|
free(llist_pop(&list));
|
|
} else {
|
|
list = list->link;
|
|
}
|
|
}
|
|
|
|
return retval;
|
|
}
|