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)
122 #if defined _MSC_VER || defined __MINGW32__
124 /* Native Woe32 API. */
132 prog_argv = prepare_spawn (prog_argv);
134 /* Save standard file handles of parent process. */
136 orig_stdin = dup_noinherit (STDIN_FILENO);
138 orig_stdout = dup_noinherit (STDOUT_FILENO);
140 orig_stderr = dup_noinherit (STDERR_FILENO);
143 /* Create standard file handles of child process. */
147 || ((nullinfd = open ("NUL", O_RDONLY, 0)) >= 0
148 && (nullinfd == STDIN_FILENO
149 || (dup2 (nullinfd, STDIN_FILENO) >= 0
150 && close (nullinfd) >= 0))))
151 && (!(null_stdout || null_stderr)
152 || ((nulloutfd = open ("NUL", O_RDWR, 0)) >= 0
154 || nulloutfd == STDOUT_FILENO
155 || dup2 (nulloutfd, STDOUT_FILENO) >= 0)
157 || nulloutfd == STDERR_FILENO
158 || dup2 (nulloutfd, STDERR_FILENO) >= 0)
159 && ((null_stdout && nulloutfd == STDOUT_FILENO)
160 || (null_stderr && nulloutfd == STDERR_FILENO)
161 || close (nulloutfd) >= 0))))
162 exitcode = spawnvp (P_WAIT, prog_path, prog_argv);
168 /* Restore standard file handles of parent process. */
170 dup2 (orig_stderr, STDERR_FILENO), close (orig_stderr);
172 dup2 (orig_stdout, STDOUT_FILENO), close (orig_stdout);
174 dup2 (orig_stdin, STDIN_FILENO), close (orig_stdin);
178 if (exit_on_error || !null_stderr)
179 error (exit_on_error ? EXIT_FAILURE : 0, errno,
180 _("%s subprocess failed"), progname);
189 /* Note about 127: Some errors during posix_spawnp() cause the function
190 posix_spawnp() to return an error code; some other errors cause the
191 subprocess to exit with return code 127. It is implementation
192 dependent which error is reported which way. We treat both cases as
195 sigset_t blocked_signals;
196 posix_spawn_file_actions_t actions;
197 bool actions_allocated;
198 posix_spawnattr_t attrs;
199 bool attrs_allocated;
209 sigprocmask (SIG_SETMASK, NULL, &blocked_signals);
210 block_fatal_signals ();
212 actions_allocated = false;
213 attrs_allocated = false;
214 if ((err = posix_spawn_file_actions_init (&actions)) != 0
215 || (actions_allocated = true,
217 && (err = posix_spawn_file_actions_addopen (&actions,
219 "/dev/null", O_RDONLY,
223 && (err = posix_spawn_file_actions_addopen (&actions,
229 && (err = posix_spawn_file_actions_addopen (&actions,
235 && ((err = posix_spawnattr_init (&attrs)) != 0
236 || (attrs_allocated = true,
237 (err = posix_spawnattr_setsigmask (&attrs,
240 || (err = posix_spawnattr_setflags (&attrs,
241 POSIX_SPAWN_SETSIGMASK))
243 || (err = posix_spawnp (&child, prog_path, &actions,
244 attrs_allocated ? &attrs : NULL, prog_argv,
248 if (actions_allocated)
249 posix_spawn_file_actions_destroy (&actions);
251 posix_spawnattr_destroy (&attrs);
253 unblock_fatal_signals ();
254 if (exit_on_error || !null_stderr)
255 error (exit_on_error ? EXIT_FAILURE : 0, err,
256 _("%s subprocess failed"), progname);
259 posix_spawn_file_actions_destroy (&actions);
261 posix_spawnattr_destroy (&attrs);
264 block_fatal_signals ();
265 /* Use vfork() instead of fork() for efficiency. */
266 if ((child = vfork ()) == 0)
268 /* Child process code. */
273 || ((nullinfd = open ("/dev/null", O_RDONLY, 0)) >= 0
274 && (nullinfd == STDIN_FILENO
275 || (dup2 (nullinfd, STDIN_FILENO) >= 0
276 && close (nullinfd) >= 0))))
277 && (!(null_stdout || null_stderr)
278 || ((nulloutfd = open ("/dev/null", O_RDWR, 0)) >= 0
280 || nulloutfd == STDOUT_FILENO
281 || dup2 (nulloutfd, STDOUT_FILENO) >= 0)
283 || nulloutfd == STDERR_FILENO
284 || dup2 (nulloutfd, STDERR_FILENO) >= 0)
285 && ((null_stdout && nulloutfd == STDOUT_FILENO)
286 || (null_stderr && nulloutfd == STDERR_FILENO)
287 || close (nulloutfd) >= 0)))
288 && (!slave_process || (unblock_fatal_signals (), true)))
289 execvp (prog_path, prog_argv);
295 unblock_fatal_signals ();
296 if (exit_on_error || !null_stderr)
297 error (exit_on_error ? EXIT_FAILURE : 0, errno,
298 _("%s subprocess failed"), progname);
304 register_slave_subprocess (child);
305 unblock_fatal_signals ();
308 return wait_subprocess (child, progname, ignore_sigpipe, null_stderr,
309 slave_process, exit_on_error);