busybox/coreutils/tee.c
Manuel Novoa III d709743b09 If read were to return with an error, bad things would happen. Fix it.
Also, make sure read errors are reflected in the applet exit code.
2004-05-26 15:21:19 +00:00

121 lines
3.3 KiB
C

/* vi: set sw=4 ts=4: */
/*
* tee implementation for busybox
*
* Copyright (C) 2003 Manuel Novoa III <mjn3@codepoet.org>
*
* 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 of the License, 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
*
*/
/* BB_AUDIT SUSv3 compliant */
/* http://www.opengroup.org/onlinepubs/007904975/utilities/tee.html */
#include <stdio.h>
#include <stdlib.h>
#include <signal.h>
#include <unistd.h>
#include "busybox.h"
int tee_main(int argc, char **argv)
{
const char *mode = "w\0a";
FILE **files;
FILE **p;
char **filenames;
int flags;
int retval = EXIT_SUCCESS;
#ifdef CONFIG_FEATURE_TEE_USE_BLOCK_IO
ssize_t c;
RESERVE_CONFIG_BUFFER(buf, BUFSIZ);
#else
int c;
#endif
flags = bb_getopt_ulflags(argc, argv, "ia"); /* 'a' must be 2nd */
mode += (flags & 2); /* Since 'a' is the 2nd option... */
if (flags & 1) {
signal(SIGINT, SIG_IGN); /* TODO - switch to sigaction.*/
}
/* gnu tee ignores SIGPIPE in case one of the output files is a pipe
* that doesn't consume all its input. Good idea... */
signal(SIGPIPE, SIG_IGN); /* TODO - switch to sigaction.*/
/* Allocate an array of FILE *'s, with one extra for a sentinal. */
p = files = (FILE **)xmalloc(sizeof(FILE *) * (argc - optind + 2));
*p = stdout;
argv += optind - 1;
filenames = argv - 1;
*filenames = (char *) bb_msg_standard_input; /* for later */
goto GOT_NEW_FILE;
do {
if ((*p = bb_wfopen(*argv, mode)) == NULL) {
retval = EXIT_FAILURE;
continue;
}
filenames[(int)(p - files)] = *argv;
GOT_NEW_FILE:
setbuf(*p, NULL); /* tee must not buffer output. */
++p;
} while (*++argv);
*p = NULL; /* Store the sentinal value. */
#ifdef CONFIG_FEATURE_TEE_USE_BLOCK_IO
while ((c = safe_read(STDIN_FILENO, buf, BUFSIZ)) > 0) {
for (p=files ; *p ; p++) {
fwrite(buf, 1, c, *p);
}
}
if (c < 0) { /* Make sure read errors are signaled. */
retval = EXIT_FAILURE;
}
#ifdef CONFIG_FEATURE_CLEAN_UP
RELEASE_CONFIG_BUFFER(buf);
#endif
#else
setvbuf(stdout, NULL, _IONBF, 0);
while ((c = getchar()) != EOF) {
for (p=files ; *p ; p++) {
putc(c, *p);
}
}
#endif
/* Now we need to check for i/o errors on stdin and the various
* output files. Since we know that the first entry in the output
* file table is stdout, we can save one "if ferror" test by
* setting the first entry to stdin and checking stdout error
* status with bb_fflush_stdout_and_exit()... although fflush()ing
* is unnecessary here. */
p = files;
*p = stdin;
do { /* Now check for (input and) output errors. */
/* Checking ferror should be sufficient, but we may want to fclose.
* If we do, remember not to close stdin! */
bb_xferror(*p, filenames[(int)(p - files)]);
} while (*++p);
bb_fflush_stdout_and_exit(retval);
}