tac: *really* add tac.c now

This commit is contained in:
Denis Vlasenko 2008-01-07 16:14:14 +00:00
parent 6b404431aa
commit 482f2b31e7

68
coreutils/tac.c Normal file
View File

@ -0,0 +1,68 @@
/* 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! */
int tac_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int tac_main(int argc, char **argv)
{
char **name;
FILE *f;
char *line;
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 {
name--;
f = fopen_or_warn_stdin(*name);
if (f == NULL) {
retval = EXIT_FAILURE;
continue;
}
errno = 0;
/* FIXME: NUL bytes are mishandled. */
while ((line = xmalloc_fgets(f)) != NULL)
llist_add_to(&list, line);
/* xmalloc_fgets uses getc and returns NULL on error or EOF. */
/* It 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) {
printf("%s", list->data);
list = list->link;
}
return retval;
}