1 /* Creation of autonomous subprocesses.
2 Copyright (C) 2001-2004, 2006-2008 Free Software Foundation, Inc.
3 Written by Bruno Haible <haible@clisp.cons.org>, 2001.
5 This program is free software: you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 3 of the License, or
8 (at your option) any later version.
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program. If not, see <http://www.gnu.org/licenses/>. */
32 #include "fatal-signal.h"
33 #include "wait-process.h"
36 #define _(str) gettext (str)
38 #if defined _MSC_VER || defined __MINGW32__
40 /* Native Woe32 API. */
42 # include "w32spawn.h"
58 # define STDIN_FILENO 0
61 # define STDOUT_FILENO 1
64 # define STDERR_FILENO 2
67 /* The results of open() in this file are not used with fchdir,
68 therefore save some unnecessary work in fchdir.c. */
75 /* EINTR handling for close(), open().
76 These functions can return -1/EINTR even though we don't have any
77 signal handlers set up, namely when we get interrupted via SIGSTOP. */
80 nonintr_close (int fd)
86 while (retval < 0 && errno == EINTR);
90 #define close nonintr_close
93 nonintr_open (const char *pathname, int oflag, mode_t mode)
98 retval = open (pathname, oflag, mode);
99 while (retval < 0 && errno == EINTR);
103 #undef open /* avoid warning on VMS */
104 #define open nonintr_open
109 /* Execute a command, optionally redirecting any of the three standard file
110 descriptors to /dev/null. Return its exit code.
111 If it didn't terminate correctly, exit if exit_on_error is true, otherwise
113 If slave_process is true, the child process will be terminated when its
114 creator receives a catchable fatal signal. */
116 execute (const char *progname,
117 const char *prog_path, char **prog_argv,
119 bool null_stdin, bool null_stdout, bool null_stderr,
120 bool slave_process, bool exit_on_error,
123 #if defined _MSC_VER || defined __MINGW32__
125 /* Native Woe32 API. */
133 prog_argv = prepare_spawn (prog_argv);
135 /* Save standard file handles of parent process. */
137 orig_stdin = dup_noinherit (STDIN_FILENO);
139 orig_stdout = dup_noinherit (STDOUT_FILENO);
141 orig_stderr = dup_noinherit (STDERR_FILENO);
144 /* Create standard file handles of child process. */
148 || ((nullinfd = open ("NUL", O_RDONLY, 0)) >= 0
149 && (nullinfd == STDIN_FILENO
150 || (dup2 (nullinfd, STDIN_FILENO) >= 0
151 && close (nullinfd) >= 0))))
152 && (!(null_stdout || null_stderr)
153 || ((nulloutfd = open ("NUL", O_RDWR, 0)) >= 0
155 || nulloutfd == STDOUT_FILENO
156 || dup2 (nulloutfd, STDOUT_FILENO) >= 0)
158 || nulloutfd == STDERR_FILENO
159 || dup2 (nulloutfd, STDERR_FILENO) >= 0)
160 && ((null_stdout && nulloutfd == STDOUT_FILENO)
161 || (null_stderr && nulloutfd == STDERR_FILENO)
162 || close (nulloutfd) >= 0))))
163 exitcode = spawnvp (P_WAIT, prog_path, prog_argv);
169 /* Restore standard file handles of parent process. */
171 dup2 (orig_stderr, STDERR_FILENO), close (orig_stderr);
173 dup2 (orig_stdout, STDOUT_FILENO), close (orig_stdout);
175 dup2 (orig_stdin, STDIN_FILENO), close (orig_stdin);
177 if (termsigp != NULL)
182 if (exit_on_error || !null_stderr)
183 error (exit_on_error ? EXIT_FAILURE : 0, errno,
184 _("%s subprocess failed"), progname);
193 /* Note about 127: Some errors during posix_spawnp() cause the function
194 posix_spawnp() to return an error code; some other errors cause the
195 subprocess to exit with return code 127. It is implementation
196 dependent which error is reported which way. We treat both cases as
199 sigset_t blocked_signals;
200 posix_spawn_file_actions_t actions;
201 bool actions_allocated;
202 posix_spawnattr_t attrs;
203 bool attrs_allocated;
213 sigprocmask (SIG_SETMASK, NULL, &blocked_signals);
214 block_fatal_signals ();
216 actions_allocated = false;
217 attrs_allocated = false;
218 if ((err = posix_spawn_file_actions_init (&actions)) != 0
219 || (actions_allocated = true,
221 && (err = posix_spawn_file_actions_addopen (&actions,
223 "/dev/null", O_RDONLY,
227 && (err = posix_spawn_file_actions_addopen (&actions,
233 && (err = posix_spawn_file_actions_addopen (&actions,
239 && ((err = posix_spawnattr_init (&attrs)) != 0
240 || (attrs_allocated = true,
241 (err = posix_spawnattr_setsigmask (&attrs,
244 || (err = posix_spawnattr_setflags (&attrs,
245 POSIX_SPAWN_SETSIGMASK))
247 || (err = posix_spawnp (&child, prog_path, &actions,
248 attrs_allocated ? &attrs : NULL, prog_argv,
252 if (actions_allocated)
253 posix_spawn_file_actions_destroy (&actions);
255 posix_spawnattr_destroy (&attrs);
257 unblock_fatal_signals ();
258 if (termsigp != NULL)
260 if (exit_on_error || !null_stderr)
261 error (exit_on_error ? EXIT_FAILURE : 0, err,
262 _("%s subprocess failed"), progname);
265 posix_spawn_file_actions_destroy (&actions);
267 posix_spawnattr_destroy (&attrs);
270 block_fatal_signals ();
271 /* Use vfork() instead of fork() for efficiency. */
272 if ((child = vfork ()) == 0)
274 /* Child process code. */
279 || ((nullinfd = open ("/dev/null", O_RDONLY, 0)) >= 0
280 && (nullinfd == STDIN_FILENO
281 || (dup2 (nullinfd, STDIN_FILENO) >= 0
282 && close (nullinfd) >= 0))))
283 && (!(null_stdout || null_stderr)
284 || ((nulloutfd = open ("/dev/null", O_RDWR, 0)) >= 0
286 || nulloutfd == STDOUT_FILENO
287 || dup2 (nulloutfd, STDOUT_FILENO) >= 0)
289 || nulloutfd == STDERR_FILENO
290 || dup2 (nulloutfd, STDERR_FILENO) >= 0)
291 && ((null_stdout && nulloutfd == STDOUT_FILENO)
292 || (null_stderr && nulloutfd == STDERR_FILENO)
293 || close (nulloutfd) >= 0)))
294 && (!slave_process || (unblock_fatal_signals (), true)))
295 execvp (prog_path, prog_argv);
301 unblock_fatal_signals ();
302 if (termsigp != NULL)
304 if (exit_on_error || !null_stderr)
305 error (exit_on_error ? EXIT_FAILURE : 0, errno,
306 _("%s subprocess failed"), progname);
312 register_slave_subprocess (child);
313 unblock_fatal_signals ();
316 return wait_subprocess (child, progname, ignore_sigpipe, null_stderr,
317 slave_process, exit_on_error, termsigp);