1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447
|
/* Creation of subprocesses, communicating via pipes.
Copyright (C) 2001-2004, 2006-2015 Free Software Foundation, Inc.
Written by Bruno Haible <haible@clisp.cons.org>, 2001.
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include <config.h>
/* Specification. */
#include "spawn-pipe.h"
#include <errno.h>
#include <fcntl.h>
#include <stdlib.h>
#include <signal.h>
#include <unistd.h>
#include "error.h"
#include "fatal-signal.h"
#include "unistd-safer.h"
#include "wait-process.h"
#include "gettext.h"
#define _(str) gettext (str)
#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
/* Native Windows API. */
# include <process.h>
# include "w32spawn.h"
#else
/* Unix API. */
# include <spawn.h>
#endif
#ifdef EINTR
/* EINTR handling for close().
These functions can return -1/EINTR even though we don't have any
signal handlers set up, namely when we get interrupted via SIGSTOP. */
static int
nonintr_close (int fd)
{
int retval;
do
retval = close (fd);
while (retval < 0 && errno == EINTR);
return retval;
}
#define close nonintr_close
#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
static int
nonintr_open (const char *pathname, int oflag, mode_t mode)
{
int retval;
do
retval = open (pathname, oflag, mode);
while (retval < 0 && errno == EINTR);
return retval;
}
# undef open /* avoid warning on VMS */
# define open nonintr_open
#endif
#endif
/* Open a pipe connected to a child process.
*
* write system read
* parent -> fd[1] -> STDIN_FILENO -> child if pipe_stdin
* parent <- fd[0] <- STDOUT_FILENO <- child if pipe_stdout
* read system write
*
* At least one of pipe_stdin, pipe_stdout must be true.
* pipe_stdin and prog_stdin together determine the child's standard input.
* pipe_stdout and prog_stdout together determine the child's standard output.
* If pipe_stdin is true, prog_stdin is ignored.
* If pipe_stdout is true, prog_stdout is ignored.
*/
static pid_t
create_pipe (const char *progname,
const char *prog_path, char **prog_argv,
bool pipe_stdin, bool pipe_stdout,
const char *prog_stdin, const char *prog_stdout,
bool null_stderr,
bool slave_process, bool exit_on_error,
int fd[2])
{
#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
/* Native Windows API.
This uses _pipe(), dup2(), and spawnv(). It could also be implemented
using the low-level functions CreatePipe(), DuplicateHandle(),
CreateProcess() and _open_osfhandle(); see the GNU make and GNU clisp
and cvs source code. */
int ifd[2];
int ofd[2];
int orig_stdin;
int orig_stdout;
int orig_stderr;
int child;
int nulloutfd;
int stdinfd;
int stdoutfd;
int saved_errno;
/* FIXME: Need to free memory allocated by prepare_spawn. */
prog_argv = prepare_spawn (prog_argv);
if (pipe_stdout)
if (pipe2_safer (ifd, O_BINARY | O_CLOEXEC) < 0)
error (EXIT_FAILURE, errno, _("cannot create pipe"));
if (pipe_stdin)
if (pipe2_safer (ofd, O_BINARY | O_CLOEXEC) < 0)
error (EXIT_FAILURE, errno, _("cannot create pipe"));
/* Data flow diagram:
*
* write system read
* parent -> ofd[1] -> ofd[0] -> child if pipe_stdin
* parent <- ifd[0] <- ifd[1] <- child if pipe_stdout
* read system write
*
*/
/* Save standard file handles of parent process. */
if (pipe_stdin || prog_stdin != NULL)
orig_stdin = dup_safer_noinherit (STDIN_FILENO);
if (pipe_stdout || prog_stdout != NULL)
orig_stdout = dup_safer_noinherit (STDOUT_FILENO);
if (null_stderr)
orig_stderr = dup_safer_noinherit (STDERR_FILENO);
child = -1;
/* Create standard file handles of child process. */
nulloutfd = -1;
stdinfd = -1;
stdoutfd = -1;
if ((!pipe_stdin || dup2 (ofd[0], STDIN_FILENO) >= 0)
&& (!pipe_stdout || dup2 (ifd[1], STDOUT_FILENO) >= 0)
&& (!null_stderr
|| ((nulloutfd = open ("NUL", O_RDWR, 0)) >= 0
&& (nulloutfd == STDERR_FILENO
|| (dup2 (nulloutfd, STDERR_FILENO) >= 0
&& close (nulloutfd) >= 0))))
&& (pipe_stdin
|| prog_stdin == NULL
|| ((stdinfd = open (prog_stdin, O_RDONLY, 0)) >= 0
&& (stdinfd == STDIN_FILENO
|| (dup2 (stdinfd, STDIN_FILENO) >= 0
&& close (stdinfd) >= 0))))
&& (pipe_stdout
|| prog_stdout == NULL
|| ((stdoutfd = open (prog_stdout, O_WRONLY, 0)) >= 0
&& (stdoutfd == STDOUT_FILENO
|| (dup2 (stdoutfd, STDOUT_FILENO) >= 0
&& close (stdoutfd) >= 0)))))
/* The child process doesn't inherit ifd[0], ifd[1], ofd[0], ofd[1],
but it inherits all open()ed or dup2()ed file handles (which is what
we want in the case of STD*_FILENO). */
/* Use spawnvpe and pass the environment explicitly. This is needed if
the program has modified the environment using putenv() or [un]setenv().
On Windows, programs have two environments, one in the "environment
block" of the process and managed through SetEnvironmentVariable(), and
one inside the process, in the location retrieved by the 'environ'
macro. When using spawnvp() without 'e', the child process inherits a
copy of the environment block - ignoring the effects of putenv() and
[un]setenv(). */
{
child = spawnvpe (P_NOWAIT, prog_path, (const char **) prog_argv,
(const char **) environ);
if (child < 0 && errno == ENOEXEC)
{
/* prog is not a native executable. Try to execute it as a
shell script. Note that prepare_spawn() has already prepended
a hidden element "sh.exe" to prog_argv. */
--prog_argv;
child = spawnvpe (P_NOWAIT, prog_argv[0], (const char **) prog_argv,
(const char **) environ);
}
}
if (child == -1)
saved_errno = errno;
if (stdinfd >= 0)
close (stdinfd);
if (stdoutfd >= 0)
close (stdoutfd);
if (nulloutfd >= 0)
close (nulloutfd);
/* Restore standard file handles of parent process. */
if (null_stderr)
undup_safer_noinherit (orig_stderr, STDERR_FILENO);
if (pipe_stdout || prog_stdout != NULL)
undup_safer_noinherit (orig_stdout, STDOUT_FILENO);
if (pipe_stdin || prog_stdin != NULL)
undup_safer_noinherit (orig_stdin, STDIN_FILENO);
if (pipe_stdin)
close (ofd[0]);
if (pipe_stdout)
close (ifd[1]);
if (child == -1)
{
if (exit_on_error || !null_stderr)
error (exit_on_error ? EXIT_FAILURE : 0, saved_errno,
_("%s subprocess failed"), progname);
if (pipe_stdout)
close (ifd[0]);
if (pipe_stdin)
close (ofd[1]);
errno = saved_errno;
return -1;
}
if (pipe_stdout)
fd[0] = ifd[0];
if (pipe_stdin)
fd[1] = ofd[1];
return child;
#else
/* Unix API. */
int ifd[2];
int ofd[2];
sigset_t blocked_signals;
posix_spawn_file_actions_t actions;
bool actions_allocated;
posix_spawnattr_t attrs;
bool attrs_allocated;
int err;
pid_t child;
if (pipe_stdout)
if (pipe_safer (ifd) < 0)
error (EXIT_FAILURE, errno, _("cannot create pipe"));
if (pipe_stdin)
if (pipe_safer (ofd) < 0)
error (EXIT_FAILURE, errno, _("cannot create pipe"));
/* Data flow diagram:
*
* write system read
* parent -> ofd[1] -> ofd[0] -> child if pipe_stdin
* parent <- ifd[0] <- ifd[1] <- child if pipe_stdout
* read system write
*
*/
if (slave_process)
{
sigprocmask (SIG_SETMASK, NULL, &blocked_signals);
block_fatal_signals ();
}
actions_allocated = false;
attrs_allocated = false;
if ((err = posix_spawn_file_actions_init (&actions)) != 0
|| (actions_allocated = true,
(pipe_stdin
&& (err = posix_spawn_file_actions_adddup2 (&actions,
ofd[0], STDIN_FILENO))
!= 0)
|| (pipe_stdout
&& (err = posix_spawn_file_actions_adddup2 (&actions,
ifd[1], STDOUT_FILENO))
!= 0)
|| (pipe_stdin
&& (err = posix_spawn_file_actions_addclose (&actions, ofd[0]))
!= 0)
|| (pipe_stdout
&& (err = posix_spawn_file_actions_addclose (&actions, ifd[1]))
!= 0)
|| (pipe_stdin
&& (err = posix_spawn_file_actions_addclose (&actions, ofd[1]))
!= 0)
|| (pipe_stdout
&& (err = posix_spawn_file_actions_addclose (&actions, ifd[0]))
!= 0)
|| (null_stderr
&& (err = posix_spawn_file_actions_addopen (&actions,
STDERR_FILENO,
"/dev/null", O_RDWR,
0))
!= 0)
|| (!pipe_stdin
&& prog_stdin != NULL
&& (err = posix_spawn_file_actions_addopen (&actions,
STDIN_FILENO,
prog_stdin, O_RDONLY,
0))
!= 0)
|| (!pipe_stdout
&& prog_stdout != NULL
&& (err = posix_spawn_file_actions_addopen (&actions,
STDOUT_FILENO,
prog_stdout, O_WRONLY,
0))
!= 0)
|| (slave_process
&& ((err = posix_spawnattr_init (&attrs)) != 0
|| (attrs_allocated = true,
(err = posix_spawnattr_setsigmask (&attrs,
&blocked_signals))
!= 0
|| (err = posix_spawnattr_setflags (&attrs,
POSIX_SPAWN_SETSIGMASK))
!= 0)))
|| (err = posix_spawnp (&child, prog_path, &actions,
attrs_allocated ? &attrs : NULL, prog_argv,
environ))
!= 0))
{
if (actions_allocated)
posix_spawn_file_actions_destroy (&actions);
if (attrs_allocated)
posix_spawnattr_destroy (&attrs);
if (slave_process)
unblock_fatal_signals ();
if (exit_on_error || !null_stderr)
error (exit_on_error ? EXIT_FAILURE : 0, err,
_("%s subprocess failed"), progname);
if (pipe_stdout)
{
close (ifd[0]);
close (ifd[1]);
}
if (pipe_stdin)
{
close (ofd[0]);
close (ofd[1]);
}
errno = err;
return -1;
}
posix_spawn_file_actions_destroy (&actions);
if (attrs_allocated)
posix_spawnattr_destroy (&attrs);
if (slave_process)
{
register_slave_subprocess (child);
unblock_fatal_signals ();
}
if (pipe_stdin)
close (ofd[0]);
if (pipe_stdout)
close (ifd[1]);
if (pipe_stdout)
fd[0] = ifd[0];
if (pipe_stdin)
fd[1] = ofd[1];
return child;
#endif
}
/* Open a bidirectional pipe.
*
* write system read
* parent -> fd[1] -> STDIN_FILENO -> child
* parent <- fd[0] <- STDOUT_FILENO <- child
* read system write
*
*/
pid_t
create_pipe_bidi (const char *progname,
const char *prog_path, char **prog_argv,
bool null_stderr,
bool slave_process, bool exit_on_error,
int fd[2])
{
pid_t result = create_pipe (progname, prog_path, prog_argv,
true, true, NULL, NULL,
null_stderr, slave_process, exit_on_error,
fd);
return result;
}
/* Open a pipe for input from a child process.
* The child's stdin comes from a file.
*
* read system write
* parent <- fd[0] <- STDOUT_FILENO <- child
*
*/
pid_t
create_pipe_in (const char *progname,
const char *prog_path, char **prog_argv,
const char *prog_stdin, bool null_stderr,
bool slave_process, bool exit_on_error,
int fd[1])
{
int iofd[2];
pid_t result = create_pipe (progname, prog_path, prog_argv,
false, true, prog_stdin, NULL,
null_stderr, slave_process, exit_on_error,
iofd);
if (result != -1)
fd[0] = iofd[0];
return result;
}
/* Open a pipe for output to a child process.
* The child's stdout goes to a file.
*
* write system read
* parent -> fd[0] -> STDIN_FILENO -> child
*
*/
pid_t
create_pipe_out (const char *progname,
const char *prog_path, char **prog_argv,
const char *prog_stdout, bool null_stderr,
bool slave_process, bool exit_on_error,
int fd[1])
{
int iofd[2];
pid_t result = create_pipe (progname, prog_path, prog_argv,
true, false, NULL, prog_stdout,
null_stderr, slave_process, exit_on_error,
iofd);
if (result != -1)
fd[0] = iofd[1];
return result;
}
|