blob: 48cc0508fced0d498a6b09fadcd54fa14adf4836
1 | /* vi: set sw=4 ts=4: */ |
2 | /* |
3 | * tee implementation for busybox |
4 | * |
5 | * Copyright (C) 2003 Manuel Novoa III <mjn3@codepoet.org> |
6 | * |
7 | * Licensed under GPLv2 or later, see file LICENSE in this source tree. |
8 | */ |
9 | |
10 | /* BB_AUDIT SUSv3 compliant */ |
11 | /* http://www.opengroup.org/onlinepubs/007904975/utilities/tee.html */ |
12 | |
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" |
24 | |
25 | #include "libbb.h" |
26 | |
27 | int tee_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; |
28 | int tee_main(int argc, char **argv) |
29 | { |
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; |
46 | |
47 | mode += (retval & 2); /* Since 'a' is the 2nd option... */ |
48 | |
49 | if (retval & 1) { |
50 | signal(SIGINT, SIG_IGN); /* TODO - switch to sigaction. (why?) */ |
51 | } |
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); |
56 | |
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; |
60 | |
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; |
71 | } |
72 | } |
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 */ |
80 | |
81 | #if ENABLE_FEATURE_TEE_USE_BLOCK_IO |
82 | while ((c = safe_read(STDIN_FILENO, buf, sizeof(buf))) > 0) { |
83 | fp = files; |
84 | do |
85 | fwrite(buf, 1, c, *fp); |
86 | while (*++fp); |
87 | } |
88 | if (c < 0) { /* Make sure read errors are signaled. */ |
89 | retval = EXIT_FAILURE; |
90 | } |
91 | #else |
92 | setvbuf(stdout, NULL, _IONBF, 0); |
93 | while ((c = getchar()) != EOF) { |
94 | fp = files; |
95 | do |
96 | putc(c, *fp); |
97 | while (*++fp); |
98 | } |
99 | #endif |
100 | |
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); |
116 | |
117 | fflush_stdout_and_exit(retval); |
118 | } |
119 |