1 /* Creation of autonomous subprocesses.
2 Copyright (C) 2001-2004, 2006-2007 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"
57 #if ! HAVE_ENVIRON_DECL
58 extern char **environ;
62 # define STDIN_FILENO 0
65 # define STDOUT_FILENO 1
68 # define STDERR_FILENO 2
71 /* The results of open() in this file are not used with fchdir,
72 therefore save some unnecessary work in fchdir.c. */
79 /* EINTR handling for close(), open().
80 These functions can return -1/EINTR even though we don't have any
81 signal handlers set up, namely when we get interrupted via SIGSTOP. */
84 nonintr_close (int fd)
90 while (retval < 0 && errno == EINTR);
94 #define close nonintr_close
97 nonintr_open (const char *pathname, int oflag, mode_t mode)
102 retval = open (pathname, oflag, mode);
103 while (retval < 0 && errno == EINTR);
107 #undef open /* avoid warning on VMS */
108 #define open nonintr_open
113 /* Execute a command, optionally redirecting any of the three standard file
114 descriptors to /dev/null. Return its exit code.
115 If it didn't terminate correctly, exit if exit_on_error is true, otherwise
117 If slave_process is true, the child process will be terminated when its
118 creator receives a catchable fatal signal. */
120 execute (const char *progname,
121 const char *prog_path, char **prog_argv,
123 bool null_stdin, bool null_stdout, bool null_stderr,
124 bool slave_process, bool exit_on_error)
126 #if defined _MSC_VER || defined __MINGW32__
128 /* Native Woe32 API. */
136 prog_argv = prepare_spawn (prog_argv);
138 /* Save standard file handles of parent process. */
140 orig_stdin = dup_noinherit (STDIN_FILENO);
142 orig_stdout = dup_noinherit (STDOUT_FILENO);
144 orig_stderr = dup_noinherit (STDERR_FILENO);
147 /* Create standard file handles of child process. */
151 || ((nullinfd = open ("NUL", O_RDONLY, 0)) >= 0
152 && (nullinfd == STDIN_FILENO
153 || (dup2 (nullinfd, STDIN_FILENO) >= 0
154 && close (nullinfd) >= 0))))
155 && (!(null_stdout || null_stderr)
156 || ((nulloutfd = open ("NUL", O_RDWR, 0)) >= 0
158 || nulloutfd == STDOUT_FILENO
159 || dup2 (nulloutfd, STDOUT_FILENO) >= 0)
161 || nulloutfd == STDERR_FILENO
162 || dup2 (nulloutfd, STDERR_FILENO) >= 0)
163 && ((null_stdout && nulloutfd == STDOUT_FILENO)
164 || (null_stderr && nulloutfd == STDERR_FILENO)
165 || close (nulloutfd) >= 0))))
166 exitcode = spawnvp (P_WAIT, prog_path, prog_argv);
172 /* Restore standard file handles of parent process. */
174 dup2 (orig_stderr, STDERR_FILENO), close (orig_stderr);
176 dup2 (orig_stdout, STDOUT_FILENO), close (orig_stdout);
178 dup2 (orig_stdin, STDIN_FILENO), close (orig_stdin);
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 (exit_on_error || !null_stderr)
259 error (exit_on_error ? EXIT_FAILURE : 0, err,
260 _("%s subprocess failed"), progname);
263 posix_spawn_file_actions_destroy (&actions);
265 posix_spawnattr_destroy (&attrs);
268 block_fatal_signals ();
269 /* Use vfork() instead of fork() for efficiency. */
270 if ((child = vfork ()) == 0)
272 /* Child process code. */
277 || ((nullinfd = open ("/dev/null", O_RDONLY, 0)) >= 0
278 && (nullinfd == STDIN_FILENO
279 || (dup2 (nullinfd, STDIN_FILENO) >= 0
280 && close (nullinfd) >= 0))))
281 && (!(null_stdout || null_stderr)
282 || ((nulloutfd = open ("/dev/null", O_RDWR, 0)) >= 0
284 || nulloutfd == STDOUT_FILENO
285 || dup2 (nulloutfd, STDOUT_FILENO) >= 0)
287 || nulloutfd == STDERR_FILENO
288 || dup2 (nulloutfd, STDERR_FILENO) >= 0)
289 && ((null_stdout && nulloutfd == STDOUT_FILENO)
290 || (null_stderr && nulloutfd == STDERR_FILENO)
291 || close (nulloutfd) >= 0)))
292 && (!slave_process || (unblock_fatal_signals (), true)))
293 execvp (prog_path, prog_argv);
299 unblock_fatal_signals ();
300 if (exit_on_error || !null_stderr)
301 error (exit_on_error ? EXIT_FAILURE : 0, errno,
302 _("%s subprocess failed"), progname);
308 register_slave_subprocess (child);
309 unblock_fatal_signals ();
312 return wait_subprocess (child, progname, ignore_sigpipe, null_stderr,
313 slave_process, exit_on_error);