1 /* Creation of autonomous subprocesses.
2 Copyright (C) 2001-2004, 2006-2016 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"
52 #if defined EINTR && ((defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__)
54 /* EINTR handling for close(), open().
55 These functions can return -1/EINTR even though we don't have any
56 signal handlers set up, namely when we get interrupted via SIGSTOP. */
59 nonintr_close (int fd)
65 while (retval < 0 && errno == EINTR);
69 #define close nonintr_close
72 nonintr_open (const char *pathname, int oflag, mode_t mode)
77 retval = open (pathname, oflag, mode);
78 while (retval < 0 && errno == EINTR);
82 #undef open /* avoid warning on VMS */
83 #define open nonintr_open
88 /* Execute a command, optionally redirecting any of the three standard file
89 descriptors to /dev/null. Return its exit code.
90 If it didn't terminate correctly, exit if exit_on_error is true, otherwise
92 If slave_process is true, the child process will be terminated when its
93 creator receives a catchable fatal signal. */
95 execute (const char *progname,
96 const char *prog_path, char **prog_argv,
98 bool null_stdin, bool null_stdout, bool null_stderr,
99 bool slave_process, bool exit_on_error,
102 #if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
104 /* Native Windows API. */
112 /* FIXME: Need to free memory allocated by prepare_spawn. */
113 prog_argv = prepare_spawn (prog_argv);
115 /* Save standard file handles of parent process. */
117 orig_stdin = dup_safer_noinherit (STDIN_FILENO);
119 orig_stdout = dup_safer_noinherit (STDOUT_FILENO);
121 orig_stderr = dup_safer_noinherit (STDERR_FILENO);
124 /* Create standard file handles of child process. */
128 || ((nullinfd = open ("NUL", O_RDONLY, 0)) >= 0
129 && (nullinfd == STDIN_FILENO
130 || (dup2 (nullinfd, STDIN_FILENO) >= 0
131 && close (nullinfd) >= 0))))
132 && (!(null_stdout || null_stderr)
133 || ((nulloutfd = open ("NUL", O_RDWR, 0)) >= 0
135 || nulloutfd == STDOUT_FILENO
136 || dup2 (nulloutfd, STDOUT_FILENO) >= 0)
138 || nulloutfd == STDERR_FILENO
139 || dup2 (nulloutfd, STDERR_FILENO) >= 0)
140 && ((null_stdout && nulloutfd == STDOUT_FILENO)
141 || (null_stderr && nulloutfd == STDERR_FILENO)
142 || close (nulloutfd) >= 0))))
143 /* Use spawnvpe and pass the environment explicitly. This is needed if
144 the program has modified the environment using putenv() or [un]setenv().
145 On Windows, programs have two environments, one in the "environment
146 block" of the process and managed through SetEnvironmentVariable(), and
147 one inside the process, in the location retrieved by the 'environ'
148 macro. When using spawnvp() without 'e', the child process inherits a
149 copy of the environment block - ignoring the effects of putenv() and
152 exitcode = spawnvpe (P_WAIT, prog_path, (const char **) prog_argv,
153 (const char **) environ);
154 if (exitcode < 0 && errno == ENOEXEC)
156 /* prog is not a native executable. Try to execute it as a
157 shell script. Note that prepare_spawn() has already prepended
158 a hidden element "sh.exe" to prog_argv. */
160 exitcode = spawnvpe (P_WAIT, prog_argv[0], (const char **) prog_argv,
161 (const char **) environ);
169 /* Restore standard file handles of parent process. */
171 undup_safer_noinherit (orig_stderr, STDERR_FILENO);
173 undup_safer_noinherit (orig_stdout, STDOUT_FILENO);
175 undup_safer_noinherit (orig_stdin, STDIN_FILENO);
177 if (termsigp != NULL)
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
198 sigset_t blocked_signals;
199 posix_spawn_file_actions_t actions;
200 bool actions_allocated;
201 posix_spawnattr_t attrs;
202 bool attrs_allocated;
208 sigprocmask (SIG_SETMASK, NULL, &blocked_signals);
209 block_fatal_signals ();
211 actions_allocated = false;
212 attrs_allocated = false;
213 if ((err = posix_spawn_file_actions_init (&actions)) != 0
214 || (actions_allocated = true,
216 && (err = posix_spawn_file_actions_addopen (&actions,
218 "/dev/null", O_RDONLY,
222 && (err = posix_spawn_file_actions_addopen (&actions,
228 && (err = posix_spawn_file_actions_addopen (&actions,
234 && ((err = posix_spawnattr_init (&attrs)) != 0
235 || (attrs_allocated = true,
236 (err = posix_spawnattr_setsigmask (&attrs,
239 || (err = posix_spawnattr_setflags (&attrs,
240 POSIX_SPAWN_SETSIGMASK))
242 || (err = posix_spawnp (&child, prog_path, &actions,
243 attrs_allocated ? &attrs : NULL, prog_argv,
247 if (actions_allocated)
248 posix_spawn_file_actions_destroy (&actions);
250 posix_spawnattr_destroy (&attrs);
252 unblock_fatal_signals ();
253 if (termsigp != NULL)
255 if (exit_on_error || !null_stderr)
256 error (exit_on_error ? EXIT_FAILURE : 0, err,
257 _("%s subprocess failed"), progname);
260 posix_spawn_file_actions_destroy (&actions);
262 posix_spawnattr_destroy (&attrs);
265 register_slave_subprocess (child);
266 unblock_fatal_signals ();
269 return wait_subprocess (child, progname, ignore_sigpipe, null_stderr,
270 slave_process, exit_on_error, termsigp);