1 /* tee - read from standard input and write to standard output and files.
2 Copyright (C) 1985-2018 Free Software Foundation, Inc.
3
4 This program is free software: you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation, either version 3 of the License, or
7 (at your option) any later version.
8
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
13
14 You should have received a copy of the GNU General Public License
15 along with this program. If not, see <https://www.gnu.org/licenses/>. */
16
17 /* Mike Parker, Richard M. Stallman, and David MacKenzie */
18
19 #include <config.h>
20 #include <sys/types.h>
21 #include <signal.h>
22 #include <getopt.h>
23
24 #include "system.h"
25 #include "argmatch.h"
26 #include "die.h"
27 #include "error.h"
28 #include "fadvise.h"
29 #include "stdio--.h"
30 #include "xbinary-io.h"
31
32 /* The official name of this program (e.g., no 'g' prefix). */
33 #define PROGRAM_NAME "tee"
34
35 #define AUTHORS \
36 proper_name ("Mike Parker"), \
37 proper_name ("Richard M. Stallman"), \
38 proper_name ("David MacKenzie")
39
40 static bool tee_files (int nfiles, char **files);
41
42 /* If true, append to output files rather than truncating them. */
43 static bool append;
44
45 /* If true, ignore interrupts. */
46 static bool ignore_interrupts;
47
48 enum output_error
49 {
50 output_error_sigpipe, /* traditional behavior, sigpipe enabled. */
51 output_error_warn, /* warn on EPIPE, but continue. */
52 output_error_warn_nopipe, /* ignore EPIPE, continue. */
53 output_error_exit, /* exit on any output error. */
54 output_error_exit_nopipe /* exit on any output error except EPIPE. */
55 };
56
57 static enum output_error output_error;
58
59 static struct option const long_options[] =
60 {
61 {"append", no_argument, NULL, 'a'},
62 {"ignore-interrupts", no_argument, NULL, 'i'},
63 {"output-error", optional_argument, NULL, 'p'},
64 {GETOPT_HELP_OPTION_DECL},
65 {GETOPT_VERSION_OPTION_DECL},
66 {NULL, 0, NULL, 0}
67 };
68
69 static char const *const output_error_args[] =
70 {
71 "warn", "warn-nopipe", "exit", "exit-nopipe", NULL
72 };
73 static enum output_error const output_error_types[] =
74 {
75 output_error_warn, output_error_warn_nopipe,
76 output_error_exit, output_error_exit_nopipe
77 };
78 ARGMATCH_VERIFY (output_error_args, output_error_types);
79
80 void
usage(int status)81 usage (int status)
82 {
83 if (status != EXIT_SUCCESS)
84 emit_try_help ();
85 else
86 {
87 printf (_("Usage: %s [OPTION]... [FILE]...\n"), program_name);
88 fputs (_("\
89 Copy standard input to each FILE, and also to standard output.\n\
90 \n\
91 -a, --append append to the given FILEs, do not overwrite\n\
92 -i, --ignore-interrupts ignore interrupt signals\n\
93 "), stdout);
94 fputs (_("\
95 -p diagnose errors writing to non pipes\n\
96 --output-error[=MODE] set behavior on write error. See MODE below\n\
97 "), stdout);
98 fputs (HELP_OPTION_DESCRIPTION, stdout);
99 fputs (VERSION_OPTION_DESCRIPTION, stdout);
100 fputs (_("\
101 \n\
102 MODE determines behavior with write errors on the outputs:\n\
103 'warn' diagnose errors writing to any output\n\
104 'warn-nopipe' diagnose errors writing to any output not a pipe\n\
105 'exit' exit on error writing to any output\n\
106 'exit-nopipe' exit on error writing to any output not a pipe\n\
107 The default MODE for the -p option is 'warn-nopipe'.\n\
108 The default operation when --output-error is not specified, is to\n\
109 exit immediately on error writing to a pipe, and diagnose errors\n\
110 writing to non pipe outputs.\n\
111 "), stdout);
112 emit_ancillary_info (PROGRAM_NAME);
113 }
114 exit (status);
115 }
116
117 int
main(int argc,char ** argv)118 main (int argc, char **argv)
119 {
120 bool ok;
121 int optc;
122
123 initialize_main (&argc, &argv);
124 set_program_name (argv[0]);
125 setlocale (LC_ALL, "");
126 bindtextdomain (PACKAGE, LOCALEDIR);
127 textdomain (PACKAGE);
128
129 atexit (close_stdout);
130
131 append = false;
132 ignore_interrupts = false;
133
134 while ((optc = getopt_long (argc, argv, "aip", long_options, NULL)) != -1)
135 {
136 switch (optc)
137 {
138 case 'a':
139 append = true;
140 break;
141
142 case 'i':
143 ignore_interrupts = true;
144 break;
145
146 case 'p':
147 if (optarg)
148 output_error = XARGMATCH ("--output-error", optarg,
149 output_error_args, output_error_types);
150 else
151 output_error = output_error_warn_nopipe;
152 break;
153
154 case_GETOPT_HELP_CHAR;
155
156 case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
157
158 default:
159 usage (EXIT_FAILURE);
160 }
161 }
162
163 if (ignore_interrupts)
164 signal (SIGINT, SIG_IGN);
165
166 if (output_error != output_error_sigpipe)
167 signal (SIGPIPE, SIG_IGN);
168
169 /* Do *not* warn if tee is given no file arguments.
170 POSIX requires that it work when given no arguments. */
171
172 ok = tee_files (argc - optind, &argv[optind]);
173 if (close (STDIN_FILENO) != 0)
174 die (EXIT_FAILURE, errno, "%s", _("standard input"));
175
176 return ok ? EXIT_SUCCESS : EXIT_FAILURE;
177 }
178
179 /* Copy the standard input into each of the NFILES files in FILES
180 and into the standard output. As a side effect, modify FILES[-1].
181 Return true if successful. */
182
183 static bool
tee_files(int nfiles,char ** files)184 tee_files (int nfiles, char **files)
185 {
186 size_t n_outputs = 0;
187 FILE **descriptors;
188 char buffer[BUFSIZ];
189 ssize_t bytes_read = 0;
190 int i;
191 bool ok = true;
192 char const *mode_string =
193 (O_BINARY
194 ? (append ? "ab" : "wb")
195 : (append ? "a" : "w"));
196
197 xset_binary_mode (STDIN_FILENO, O_BINARY);
198 xset_binary_mode (STDOUT_FILENO, O_BINARY);
199 fadvise (stdin, FADVISE_SEQUENTIAL);
200
201 /* Set up FILES[0 .. NFILES] and DESCRIPTORS[0 .. NFILES].
202 In both arrays, entry 0 corresponds to standard output. */
203
204 descriptors = xnmalloc (nfiles + 1, sizeof *descriptors);
205 files--;
206 descriptors[0] = stdout;
207 files[0] = bad_cast (_("standard output"));
208 setvbuf (stdout, NULL, _IONBF, 0);
209 n_outputs++;
210
211 for (i = 1; i <= nfiles; i++)
212 {
213 /* Do not treat "-" specially - as mandated by POSIX. */
214 descriptors[i] = fopen (files[i], mode_string);
215 if (descriptors[i] == NULL)
216 {
217 error (output_error == output_error_exit
218 || output_error == output_error_exit_nopipe,
219 errno, "%s", quotef (files[i]));
220 ok = false;
221 }
222 else
223 {
224 setvbuf (descriptors[i], NULL, _IONBF, 0);
225 n_outputs++;
226 }
227 }
228
229 while (n_outputs)
230 {
231 bytes_read = read (0, buffer, sizeof buffer);
232 if (bytes_read < 0 && errno == EINTR)
233 continue;
234 if (bytes_read <= 0)
235 break;
236
237 /* Write to all NFILES + 1 descriptors.
238 Standard output is the first one. */
239 for (i = 0; i <= nfiles; i++)
240 if (descriptors[i]
241 && fwrite (buffer, bytes_read, 1, descriptors[i]) != 1)
242 {
243 int w_errno = errno;
244 bool fail = errno != EPIPE || (output_error == output_error_exit
245 || output_error == output_error_warn);
246 if (descriptors[i] == stdout)
247 clearerr (stdout); /* Avoid redundant close_stdout diagnostic. */
248 if (fail)
249 {
250 error (output_error == output_error_exit
251 || output_error == output_error_exit_nopipe,
252 w_errno, "%s", quotef (files[i]));
253 }
254 descriptors[i] = NULL;
255 if (fail)
256 ok = false;
257 n_outputs--;
258 }
259 }
260
261 if (bytes_read == -1)
262 {
263 error (0, errno, _("read error"));
264 ok = false;
265 }
266
267 /* Close the files, but not standard output. */
268 for (i = 1; i <= nfiles; i++)
269 if (descriptors[i] && fclose (descriptors[i]) != 0)
270 {
271 error (0, errno, "%s", quotef (files[i]));
272 ok = false;
273 }
274
275 free (descriptors);
276
277 return ok;
278 }
279