1 /* Creation of autonomous subprocesses.
2 Copyright (C) 2001-2004, 2006-2009 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"
51 /* The results of open() in this file are not used with fchdir,
52 therefore save some unnecessary work in fchdir.c. */
59 /* EINTR handling for close(), open().
60 These functions can return -1/EINTR even though we don't have any
61 signal handlers set up, namely when we get interrupted via SIGSTOP. */
64 nonintr_close (int fd)
70 while (retval < 0 && errno == EINTR);
74 #define close nonintr_close
77 nonintr_open (const char *pathname, int oflag, mode_t mode)
82 retval = open (pathname, oflag, mode);
83 while (retval < 0 && errno == EINTR);
87 #undef open /* avoid warning on VMS */
88 #define open nonintr_open
93 /* Execute a command, optionally redirecting any of the three standard file
94 descriptors to /dev/null. Return its exit code.
95 If it didn't terminate correctly, exit if exit_on_error is true, otherwise
97 If slave_process is true, the child process will be terminated when its
98 creator receives a catchable fatal signal. */
100 execute (const char *progname,
101 const char *prog_path, char **prog_argv,
103 bool null_stdin, bool null_stdout, bool null_stderr,
104 bool slave_process, bool exit_on_error,
107 #if defined _MSC_VER || defined __MINGW32__
109 /* Native Woe32 API. */
117 /* FIXME: Need to free memory allocated by prepare_spawn. */
118 prog_argv = prepare_spawn (prog_argv);
120 /* Save standard file handles of parent process. */
122 orig_stdin = dup_noinherit (STDIN_FILENO);
124 orig_stdout = dup_noinherit (STDOUT_FILENO);
126 orig_stderr = dup_noinherit (STDERR_FILENO);
129 /* Create standard file handles of child process. */
133 || ((nullinfd = open ("NUL", O_RDONLY, 0)) >= 0
134 && (nullinfd == STDIN_FILENO
135 || (dup2 (nullinfd, STDIN_FILENO) >= 0
136 && close (nullinfd) >= 0))))
137 && (!(null_stdout || null_stderr)
138 || ((nulloutfd = open ("NUL", O_RDWR, 0)) >= 0
140 || nulloutfd == STDOUT_FILENO
141 || dup2 (nulloutfd, STDOUT_FILENO) >= 0)
143 || nulloutfd == STDERR_FILENO
144 || dup2 (nulloutfd, STDERR_FILENO) >= 0)
145 && ((null_stdout && nulloutfd == STDOUT_FILENO)
146 || (null_stderr && nulloutfd == STDERR_FILENO)
147 || close (nulloutfd) >= 0))))
148 /* Use spawnvpe and pass the environment explicitly. This is needed if
149 the program has modified the environment using putenv() or [un]setenv().
150 On Windows, programs have two environments, one in the "environment
151 block" of the process and managed through SetEnvironmentVariable(), and
152 one inside the process, in the location retrieved by the 'environ'
153 macro. When using spawnvp() without 'e', the child process inherits a
154 copy of the environment block - ignoring the effects of putenv() and
157 exitcode = spawnvpe (P_WAIT, prog_path, prog_argv, environ);
158 if (exitcode < 0 && errno == ENOEXEC)
160 /* prog is not an native executable. Try to execute it as a
161 shell script. Note that prepare_spawn() has already prepended
162 a hidden element "sh.exe" to prog_argv. */
164 exitcode = spawnvpe (P_WAIT, prog_argv[0], prog_argv, environ);
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);
180 if (termsigp != NULL)
185 if (exit_on_error || !null_stderr)
186 error (exit_on_error ? EXIT_FAILURE : 0, errno,
187 _("%s subprocess failed"), progname);
196 /* Note about 127: Some errors during posix_spawnp() cause the function
197 posix_spawnp() to return an error code; some other errors cause the
198 subprocess to exit with return code 127. It is implementation
199 dependent which error is reported which way. We treat both cases as
201 sigset_t blocked_signals;
202 posix_spawn_file_actions_t actions;
203 bool actions_allocated;
204 posix_spawnattr_t attrs;
205 bool attrs_allocated;
211 sigprocmask (SIG_SETMASK, NULL, &blocked_signals);
212 block_fatal_signals ();
214 actions_allocated = false;
215 attrs_allocated = false;
216 if ((err = posix_spawn_file_actions_init (&actions)) != 0
217 || (actions_allocated = true,
219 && (err = posix_spawn_file_actions_addopen (&actions,
221 "/dev/null", O_RDONLY,
225 && (err = posix_spawn_file_actions_addopen (&actions,
231 && (err = posix_spawn_file_actions_addopen (&actions,
237 && ((err = posix_spawnattr_init (&attrs)) != 0
238 || (attrs_allocated = true,
239 (err = posix_spawnattr_setsigmask (&attrs,
242 || (err = posix_spawnattr_setflags (&attrs,
243 POSIX_SPAWN_SETSIGMASK))
245 || (err = posix_spawnp (&child, prog_path, &actions,
246 attrs_allocated ? &attrs : NULL, prog_argv,
250 if (actions_allocated)
251 posix_spawn_file_actions_destroy (&actions);
253 posix_spawnattr_destroy (&attrs);
255 unblock_fatal_signals ();
256 if (termsigp != NULL)
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 register_slave_subprocess (child);
269 unblock_fatal_signals ();
272 return wait_subprocess (child, progname, ignore_sigpipe, null_stderr,
273 slave_process, exit_on_error, termsigp);