1 /* Creation of autonomous subprocesses.
2 Copyright (C) 2001-2004, 2006-2013 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 _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
40 /* Native Windows 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. */
57 /* Execute a command, optionally redirecting any of the three standard file
58 descriptors to /dev/null. Return its exit code.
59 If it didn't terminate correctly, exit if exit_on_error is true, otherwise
61 If slave_process is true, the child process will be terminated when its
62 creator receives a catchable fatal signal. */
64 execute (const char *progname,
65 const char *prog_path, char **prog_argv,
67 bool null_stdin, bool null_stdout, bool null_stderr,
68 bool slave_process, bool exit_on_error,
71 #if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
73 /* Native Windows API. */
81 /* FIXME: Need to free memory allocated by prepare_spawn. */
82 prog_argv = prepare_spawn (prog_argv);
84 /* Save standard file handles of parent process. */
86 orig_stdin = dup_safer_noinherit (STDIN_FILENO);
88 orig_stdout = dup_safer_noinherit (STDOUT_FILENO);
90 orig_stderr = dup_safer_noinherit (STDERR_FILENO);
93 /* Create standard file handles of child process. */
97 || ((nullinfd = open ("NUL", O_RDONLY, 0)) >= 0
98 && (nullinfd == STDIN_FILENO
99 || (dup2 (nullinfd, STDIN_FILENO) >= 0
100 && close (nullinfd) >= 0))))
101 && (!(null_stdout || null_stderr)
102 || ((nulloutfd = open ("NUL", O_RDWR, 0)) >= 0
104 || nulloutfd == STDOUT_FILENO
105 || dup2 (nulloutfd, STDOUT_FILENO) >= 0)
107 || nulloutfd == STDERR_FILENO
108 || dup2 (nulloutfd, STDERR_FILENO) >= 0)
109 && ((null_stdout && nulloutfd == STDOUT_FILENO)
110 || (null_stderr && nulloutfd == STDERR_FILENO)
111 || close (nulloutfd) >= 0))))
112 /* Use spawnvpe and pass the environment explicitly. This is needed if
113 the program has modified the environment using putenv() or [un]setenv().
114 On Windows, programs have two environments, one in the "environment
115 block" of the process and managed through SetEnvironmentVariable(), and
116 one inside the process, in the location retrieved by the 'environ'
117 macro. When using spawnvp() without 'e', the child process inherits a
118 copy of the environment block - ignoring the effects of putenv() and
121 exitcode = spawnvpe (P_WAIT, prog_path, (const char **) prog_argv,
122 (const char **) environ);
123 if (exitcode < 0 && errno == ENOEXEC)
125 /* prog is not a native executable. Try to execute it as a
126 shell script. Note that prepare_spawn() has already prepended
127 a hidden element "sh.exe" to prog_argv. */
129 exitcode = spawnvpe (P_WAIT, prog_argv[0], (const char **) prog_argv,
130 (const char **) environ);
138 /* Restore standard file handles of parent process. */
140 undup_safer_noinherit (orig_stderr, STDERR_FILENO);
142 undup_safer_noinherit (orig_stdout, STDOUT_FILENO);
144 undup_safer_noinherit (orig_stdin, STDIN_FILENO);
146 if (termsigp != NULL)
151 if (exit_on_error || !null_stderr)
152 error (exit_on_error ? EXIT_FAILURE : 0, errno,
153 _("%s subprocess failed"), progname);
162 /* Note about 127: Some errors during posix_spawnp() cause the function
163 posix_spawnp() to return an error code; some other errors cause the
164 subprocess to exit with return code 127. It is implementation
165 dependent which error is reported which way. We treat both cases as
167 sigset_t blocked_signals;
168 posix_spawn_file_actions_t actions;
169 bool actions_allocated;
170 posix_spawnattr_t attrs;
171 bool attrs_allocated;
177 sigprocmask (SIG_SETMASK, NULL, &blocked_signals);
178 block_fatal_signals ();
180 actions_allocated = false;
181 attrs_allocated = false;
182 if ((err = posix_spawn_file_actions_init (&actions)) != 0
183 || (actions_allocated = true,
185 && (err = posix_spawn_file_actions_addopen (&actions,
187 "/dev/null", O_RDONLY,
191 && (err = posix_spawn_file_actions_addopen (&actions,
197 && (err = posix_spawn_file_actions_addopen (&actions,
203 && ((err = posix_spawnattr_init (&attrs)) != 0
204 || (attrs_allocated = true,
205 (err = posix_spawnattr_setsigmask (&attrs,
208 || (err = posix_spawnattr_setflags (&attrs,
209 POSIX_SPAWN_SETSIGMASK))
211 || (err = posix_spawnp (&child, prog_path, &actions,
212 attrs_allocated ? &attrs : NULL, prog_argv,
216 if (actions_allocated)
217 posix_spawn_file_actions_destroy (&actions);
219 posix_spawnattr_destroy (&attrs);
221 unblock_fatal_signals ();
222 if (termsigp != NULL)
224 if (exit_on_error || !null_stderr)
225 error (exit_on_error ? EXIT_FAILURE : 0, err,
226 _("%s subprocess failed"), progname);
229 posix_spawn_file_actions_destroy (&actions);
231 posix_spawnattr_destroy (&attrs);
234 register_slave_subprocess (child);
235 unblock_fatal_signals ();
238 return wait_subprocess (child, progname, ignore_sigpipe, null_stderr,
239 slave_process, exit_on_error, termsigp);