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 /* FIXME: Need to free memory allocated by prepare_spawn. */
134 prog_argv = prepare_spawn (prog_argv);
136 /* Save standard file handles of parent process. */
138 orig_stdin = dup_noinherit (STDIN_FILENO);
140 orig_stdout = dup_noinherit (STDOUT_FILENO);
142 orig_stderr = dup_noinherit (STDERR_FILENO);
145 /* Create standard file handles of child process. */
149 || ((nullinfd = open ("NUL", O_RDONLY, 0)) >= 0
150 && (nullinfd == STDIN_FILENO
151 || (dup2 (nullinfd, STDIN_FILENO) >= 0
152 && close (nullinfd) >= 0))))
153 && (!(null_stdout || null_stderr)
154 || ((nulloutfd = open ("NUL", O_RDWR, 0)) >= 0
156 || nulloutfd == STDOUT_FILENO
157 || dup2 (nulloutfd, STDOUT_FILENO) >= 0)
159 || nulloutfd == STDERR_FILENO
160 || dup2 (nulloutfd, STDERR_FILENO) >= 0)
161 && ((null_stdout && nulloutfd == STDOUT_FILENO)
162 || (null_stderr && nulloutfd == STDERR_FILENO)
163 || close (nulloutfd) >= 0))))
165 exitcode = spawnvp (P_WAIT, prog_path, prog_argv);
166 if (exitcode < 0 && errno == ENOEXEC)
168 /* prog is not an native executable. Try to execute it as a
169 shell script. Note that prepare_spawn() has already prepended
170 a hidden element "sh.exe" to prog_argv. */
172 exitcode = spawnvp (P_WAIT, prog_argv[0], prog_argv);
180 /* Restore standard file handles of parent process. */
182 dup2 (orig_stderr, STDERR_FILENO), close (orig_stderr);
184 dup2 (orig_stdout, STDOUT_FILENO), close (orig_stdout);
186 dup2 (orig_stdin, STDIN_FILENO), close (orig_stdin);
188 if (termsigp != NULL)
193 if (exit_on_error || !null_stderr)
194 error (exit_on_error ? EXIT_FAILURE : 0, errno,
195 _("%s subprocess failed"), progname);
204 /* Note about 127: Some errors during posix_spawnp() cause the function
205 posix_spawnp() to return an error code; some other errors cause the
206 subprocess to exit with return code 127. It is implementation
207 dependent which error is reported which way. We treat both cases as
210 sigset_t blocked_signals;
211 posix_spawn_file_actions_t actions;
212 bool actions_allocated;
213 posix_spawnattr_t attrs;
214 bool attrs_allocated;
224 sigprocmask (SIG_SETMASK, NULL, &blocked_signals);
225 block_fatal_signals ();
227 actions_allocated = false;
228 attrs_allocated = false;
229 if ((err = posix_spawn_file_actions_init (&actions)) != 0
230 || (actions_allocated = true,
232 && (err = posix_spawn_file_actions_addopen (&actions,
234 "/dev/null", O_RDONLY,
238 && (err = posix_spawn_file_actions_addopen (&actions,
244 && (err = posix_spawn_file_actions_addopen (&actions,
250 && ((err = posix_spawnattr_init (&attrs)) != 0
251 || (attrs_allocated = true,
252 (err = posix_spawnattr_setsigmask (&attrs,
255 || (err = posix_spawnattr_setflags (&attrs,
256 POSIX_SPAWN_SETSIGMASK))
258 || (err = posix_spawnp (&child, prog_path, &actions,
259 attrs_allocated ? &attrs : NULL, prog_argv,
263 if (actions_allocated)
264 posix_spawn_file_actions_destroy (&actions);
266 posix_spawnattr_destroy (&attrs);
268 unblock_fatal_signals ();
269 if (termsigp != NULL)
271 if (exit_on_error || !null_stderr)
272 error (exit_on_error ? EXIT_FAILURE : 0, err,
273 _("%s subprocess failed"), progname);
276 posix_spawn_file_actions_destroy (&actions);
278 posix_spawnattr_destroy (&attrs);
281 block_fatal_signals ();
282 /* Use vfork() instead of fork() for efficiency. */
283 if ((child = vfork ()) == 0)
285 /* Child process code. */
290 || ((nullinfd = open ("/dev/null", O_RDONLY, 0)) >= 0
291 && (nullinfd == STDIN_FILENO
292 || (dup2 (nullinfd, STDIN_FILENO) >= 0
293 && close (nullinfd) >= 0))))
294 && (!(null_stdout || null_stderr)
295 || ((nulloutfd = open ("/dev/null", O_RDWR, 0)) >= 0
297 || nulloutfd == STDOUT_FILENO
298 || dup2 (nulloutfd, STDOUT_FILENO) >= 0)
300 || nulloutfd == STDERR_FILENO
301 || dup2 (nulloutfd, STDERR_FILENO) >= 0)
302 && ((null_stdout && nulloutfd == STDOUT_FILENO)
303 || (null_stderr && nulloutfd == STDERR_FILENO)
304 || close (nulloutfd) >= 0)))
305 && (!slave_process || (unblock_fatal_signals (), true)))
306 execvp (prog_path, prog_argv);
312 unblock_fatal_signals ();
313 if (termsigp != NULL)
315 if (exit_on_error || !null_stderr)
316 error (exit_on_error ? EXIT_FAILURE : 0, errno,
317 _("%s subprocess failed"), progname);
323 register_slave_subprocess (child);
324 unblock_fatal_signals ();
327 return wait_subprocess (child, progname, ignore_sigpipe, null_stderr,
328 slave_process, exit_on_error, termsigp);