Changes for kernel and Busybox
[tomato.git] / release / src / router / busybox / coreutils / tee.c
blob48cc0508fced0d498a6b09fadcd54fa14adf4836
1 /* vi: set sw=4 ts=4: */
2 /*
3 * tee implementation for busybox
5 * Copyright (C) 2003 Manuel Novoa III <mjn3@codepoet.org>
7 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
8 */
10 /* BB_AUDIT SUSv3 compliant */
11 /* http://www.opengroup.org/onlinepubs/007904975/utilities/tee.html */
13 //usage:#define tee_trivial_usage
14 //usage: "[-ai] [FILE]..."
15 //usage:#define tee_full_usage "\n\n"
16 //usage: "Copy stdin to each FILE, and also to stdout\n"
17 //usage: "\n -a Append to the given FILEs, don't overwrite"
18 //usage: "\n -i Ignore interrupt signals (SIGINT)"
19 //usage:
20 //usage:#define tee_example_usage
21 //usage: "$ echo \"Hello\" | tee /tmp/foo\n"
22 //usage: "$ cat /tmp/foo\n"
23 //usage: "Hello\n"
25 #include "libbb.h"
27 int tee_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
28 int tee_main(int argc, char **argv)
30 const char *mode = "w\0a";
31 FILE **files;
32 FILE **fp;
33 char **names;
34 char **np;
35 char retval;
36 //TODO: make unconditional
37 #if ENABLE_FEATURE_TEE_USE_BLOCK_IO
38 ssize_t c;
39 # define buf bb_common_bufsiz1
40 #else
41 int c;
42 #endif
43 retval = getopt32(argv, "ia"); /* 'a' must be 2nd */
44 argc -= optind;
45 argv += optind;
47 mode += (retval & 2); /* Since 'a' is the 2nd option... */
49 if (retval & 1) {
50 signal(SIGINT, SIG_IGN); /* TODO - switch to sigaction. (why?) */
52 retval = EXIT_SUCCESS;
53 /* gnu tee ignores SIGPIPE in case one of the output files is a pipe
54 * that doesn't consume all its input. Good idea... */
55 signal(SIGPIPE, SIG_IGN);
57 /* Allocate an array of FILE *'s, with one extra for a sentinel. */
58 fp = files = xzalloc(sizeof(FILE *) * (argc + 2));
59 np = names = argv - 1;
61 files[0] = stdout;
62 goto GOT_NEW_FILE;
63 do {
64 *fp = stdout;
65 if (NOT_LONE_DASH(*argv)) {
66 *fp = fopen_or_warn(*argv, mode);
67 if (*fp == NULL) {
68 retval = EXIT_FAILURE;
69 argv++;
70 continue;
73 *np = *argv++;
74 GOT_NEW_FILE:
75 setbuf(*fp, NULL); /* tee must not buffer output. */
76 fp++;
77 np++;
78 } while (*argv);
79 /* names[0] will be filled later */
81 #if ENABLE_FEATURE_TEE_USE_BLOCK_IO
82 while ((c = safe_read(STDIN_FILENO, buf, sizeof(buf))) > 0) {
83 fp = files;
85 fwrite(buf, 1, c, *fp);
86 while (*++fp);
88 if (c < 0) { /* Make sure read errors are signaled. */
89 retval = EXIT_FAILURE;
91 #else
92 setvbuf(stdout, NULL, _IONBF, 0);
93 while ((c = getchar()) != EOF) {
94 fp = files;
96 putc(c, *fp);
97 while (*++fp);
99 #endif
101 /* Now we need to check for i/o errors on stdin and the various
102 * output files. Since we know that the first entry in the output
103 * file table is stdout, we can save one "if ferror" test by
104 * setting the first entry to stdin and checking stdout error
105 * status with fflush_stdout_and_exit()... although fflush()ing
106 * is unnecessary here. */
107 np = names;
108 fp = files;
109 names[0] = (char *) bb_msg_standard_input;
110 files[0] = stdin;
111 do { /* Now check for input and output errors. */
112 /* Checking ferror should be sufficient, but we may want to fclose.
113 * If we do, remember not to close stdin! */
114 die_if_ferror(*fp++, *np++);
115 } while (*fp);
117 fflush_stdout_and_exit(retval);