| 1 | /* Utilities to execute a program in a subprocess (possibly linked by pipes |
| 2 | with other subprocesses), and wait for it. Generic Unix version |
| 3 | (also used for UWIN and VMS). |
| 4 | Copyright (C) 1996-2017 Free Software Foundation, Inc. |
| 5 | |
| 6 | This file is part of the libiberty library. |
| 7 | Libiberty is free software; you can redistribute it and/or |
| 8 | modify it under the terms of the GNU Library General Public |
| 9 | License as published by the Free Software Foundation; either |
| 10 | version 2 of the License, or (at your option) any later version. |
| 11 | |
| 12 | Libiberty is distributed in the hope that it will be useful, |
| 13 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 15 | Library General Public License for more details. |
| 16 | |
| 17 | You should have received a copy of the GNU Library General Public |
| 18 | License along with libiberty; see the file COPYING.LIB. If not, |
| 19 | write to the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor, |
| 20 | Boston, MA 02110-1301, USA. */ |
| 21 | |
| 22 | #include "config.h" |
| 23 | #include "libiberty.h" |
| 24 | #include "pex-common.h" |
| 25 | #include "environ.h" |
| 26 | |
| 27 | #include <stdio.h> |
| 28 | #include <signal.h> |
| 29 | #include <errno.h> |
| 30 | #ifdef NEED_DECLARATION_ERRNO |
| 31 | extern int errno; |
| 32 | #endif |
| 33 | #ifdef HAVE_STDLIB_H |
| 34 | #include <stdlib.h> |
| 35 | #endif |
| 36 | #ifdef HAVE_STRING_H |
| 37 | #include <string.h> |
| 38 | #endif |
| 39 | #ifdef HAVE_UNISTD_H |
| 40 | #include <unistd.h> |
| 41 | #endif |
| 42 | |
| 43 | #include <sys/types.h> |
| 44 | |
| 45 | #ifdef HAVE_FCNTL_H |
| 46 | #include <fcntl.h> |
| 47 | #endif |
| 48 | #ifdef HAVE_SYS_WAIT_H |
| 49 | #include <sys/wait.h> |
| 50 | #endif |
| 51 | #ifdef HAVE_GETRUSAGE |
| 52 | #include <sys/time.h> |
| 53 | #include <sys/resource.h> |
| 54 | #endif |
| 55 | #ifdef HAVE_SYS_STAT_H |
| 56 | #include <sys/stat.h> |
| 57 | #endif |
| 58 | #ifdef HAVE_PROCESS_H |
| 59 | #include <process.h> |
| 60 | #endif |
| 61 | |
| 62 | #ifdef vfork /* Autoconf may define this to fork for us. */ |
| 63 | # define VFORK_STRING "fork" |
| 64 | #else |
| 65 | # define VFORK_STRING "vfork" |
| 66 | #endif |
| 67 | #ifdef HAVE_VFORK_H |
| 68 | #include <vfork.h> |
| 69 | #endif |
| 70 | #if defined(VMS) && defined (__LONG_POINTERS) |
| 71 | #ifndef __CHAR_PTR32 |
| 72 | typedef char * __char_ptr32 |
| 73 | __attribute__ ((mode (SI))); |
| 74 | #endif |
| 75 | |
| 76 | typedef __char_ptr32 *__char_ptr_char_ptr32 |
| 77 | __attribute__ ((mode (SI))); |
| 78 | |
| 79 | /* Return a 32 bit pointer to an array of 32 bit pointers |
| 80 | given a 64 bit pointer to an array of 64 bit pointers. */ |
| 81 | |
| 82 | static __char_ptr_char_ptr32 |
| 83 | to_ptr32 (char **ptr64) |
| 84 | { |
| 85 | int argc; |
| 86 | __char_ptr_char_ptr32 short_argv; |
| 87 | |
| 88 | /* Count number of arguments. */ |
| 89 | for (argc = 0; ptr64[argc] != NULL; argc++) |
| 90 | ; |
| 91 | |
| 92 | /* Reallocate argv with 32 bit pointers. */ |
| 93 | short_argv = (__char_ptr_char_ptr32) decc$malloc |
| 94 | (sizeof (__char_ptr32) * (argc + 1)); |
| 95 | |
| 96 | for (argc = 0; ptr64[argc] != NULL; argc++) |
| 97 | short_argv[argc] = (__char_ptr32) decc$strdup (ptr64[argc]); |
| 98 | |
| 99 | short_argv[argc] = (__char_ptr32) 0; |
| 100 | return short_argv; |
| 101 | |
| 102 | } |
| 103 | #else |
| 104 | #define to_ptr32(argv) argv |
| 105 | #endif |
| 106 | |
| 107 | /* File mode to use for private and world-readable files. */ |
| 108 | |
| 109 | #if defined (S_IRUSR) && defined (S_IWUSR) && defined (S_IRGRP) && defined (S_IWGRP) && defined (S_IROTH) && defined (S_IWOTH) |
| 110 | #define PUBLIC_MODE \ |
| 111 | (S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH) |
| 112 | #else |
| 113 | #define PUBLIC_MODE 0666 |
| 114 | #endif |
| 115 | |
| 116 | /* Get the exit status of a particular process, and optionally get the |
| 117 | time that it took. This is simple if we have wait4, slightly |
| 118 | harder if we have waitpid, and is a pain if we only have wait. */ |
| 119 | |
| 120 | static pid_t pex_wait (struct pex_obj *, pid_t, int *, struct pex_time *); |
| 121 | |
| 122 | #ifdef HAVE_WAIT4 |
| 123 | |
| 124 | static pid_t |
| 125 | pex_wait (struct pex_obj *obj ATTRIBUTE_UNUSED, pid_t pid, int *status, |
| 126 | struct pex_time *time) |
| 127 | { |
| 128 | pid_t ret; |
| 129 | struct rusage r; |
| 130 | |
| 131 | #ifdef HAVE_WAITPID |
| 132 | if (time == NULL) |
| 133 | return waitpid (pid, status, 0); |
| 134 | #endif |
| 135 | |
| 136 | ret = wait4 (pid, status, 0, &r); |
| 137 | |
| 138 | if (time != NULL) |
| 139 | { |
| 140 | time->user_seconds = r.ru_utime.tv_sec; |
| 141 | time->user_microseconds= r.ru_utime.tv_usec; |
| 142 | time->system_seconds = r.ru_stime.tv_sec; |
| 143 | time->system_microseconds= r.ru_stime.tv_usec; |
| 144 | } |
| 145 | |
| 146 | return ret; |
| 147 | } |
| 148 | |
| 149 | #else /* ! defined (HAVE_WAIT4) */ |
| 150 | |
| 151 | #ifdef HAVE_WAITPID |
| 152 | |
| 153 | #ifndef HAVE_GETRUSAGE |
| 154 | |
| 155 | static pid_t |
| 156 | pex_wait (struct pex_obj *obj ATTRIBUTE_UNUSED, pid_t pid, int *status, |
| 157 | struct pex_time *time) |
| 158 | { |
| 159 | if (time != NULL) |
| 160 | memset (time, 0, sizeof (struct pex_time)); |
| 161 | return waitpid (pid, status, 0); |
| 162 | } |
| 163 | |
| 164 | #else /* defined (HAVE_GETRUSAGE) */ |
| 165 | |
| 166 | static pid_t |
| 167 | pex_wait (struct pex_obj *obj ATTRIBUTE_UNUSED, pid_t pid, int *status, |
| 168 | struct pex_time *time) |
| 169 | { |
| 170 | struct rusage r1, r2; |
| 171 | pid_t ret; |
| 172 | |
| 173 | if (time == NULL) |
| 174 | return waitpid (pid, status, 0); |
| 175 | |
| 176 | getrusage (RUSAGE_CHILDREN, &r1); |
| 177 | |
| 178 | ret = waitpid (pid, status, 0); |
| 179 | if (ret < 0) |
| 180 | return ret; |
| 181 | |
| 182 | getrusage (RUSAGE_CHILDREN, &r2); |
| 183 | |
| 184 | time->user_seconds = r2.ru_utime.tv_sec - r1.ru_utime.tv_sec; |
| 185 | time->user_microseconds = r2.ru_utime.tv_usec - r1.ru_utime.tv_usec; |
| 186 | if (r2.ru_utime.tv_usec < r1.ru_utime.tv_usec) |
| 187 | { |
| 188 | --time->user_seconds; |
| 189 | time->user_microseconds += 1000000; |
| 190 | } |
| 191 | |
| 192 | time->system_seconds = r2.ru_stime.tv_sec - r1.ru_stime.tv_sec; |
| 193 | time->system_microseconds = r2.ru_stime.tv_usec - r1.ru_stime.tv_usec; |
| 194 | if (r2.ru_stime.tv_usec < r1.ru_stime.tv_usec) |
| 195 | { |
| 196 | --time->system_seconds; |
| 197 | time->system_microseconds += 1000000; |
| 198 | } |
| 199 | |
| 200 | return ret; |
| 201 | } |
| 202 | |
| 203 | #endif /* defined (HAVE_GETRUSAGE) */ |
| 204 | |
| 205 | #else /* ! defined (HAVE_WAITPID) */ |
| 206 | |
| 207 | struct status_list |
| 208 | { |
| 209 | struct status_list *next; |
| 210 | pid_t pid; |
| 211 | int status; |
| 212 | struct pex_time time; |
| 213 | }; |
| 214 | |
| 215 | static pid_t |
| 216 | pex_wait (struct pex_obj *obj, pid_t pid, int *status, struct pex_time *time) |
| 217 | { |
| 218 | struct status_list **pp; |
| 219 | |
| 220 | for (pp = (struct status_list **) &obj->sysdep; |
| 221 | *pp != NULL; |
| 222 | pp = &(*pp)->next) |
| 223 | { |
| 224 | if ((*pp)->pid == pid) |
| 225 | { |
| 226 | struct status_list *p; |
| 227 | |
| 228 | p = *pp; |
| 229 | *status = p->status; |
| 230 | if (time != NULL) |
| 231 | *time = p->time; |
| 232 | *pp = p->next; |
| 233 | free (p); |
| 234 | return pid; |
| 235 | } |
| 236 | } |
| 237 | |
| 238 | while (1) |
| 239 | { |
| 240 | pid_t cpid; |
| 241 | struct status_list *psl; |
| 242 | struct pex_time pt; |
| 243 | #ifdef HAVE_GETRUSAGE |
| 244 | struct rusage r1, r2; |
| 245 | #endif |
| 246 | |
| 247 | if (time != NULL) |
| 248 | { |
| 249 | #ifdef HAVE_GETRUSAGE |
| 250 | getrusage (RUSAGE_CHILDREN, &r1); |
| 251 | #else |
| 252 | memset (&pt, 0, sizeof (struct pex_time)); |
| 253 | #endif |
| 254 | } |
| 255 | |
| 256 | cpid = wait (status); |
| 257 | |
| 258 | #ifdef HAVE_GETRUSAGE |
| 259 | if (time != NULL && cpid >= 0) |
| 260 | { |
| 261 | getrusage (RUSAGE_CHILDREN, &r2); |
| 262 | |
| 263 | pt.user_seconds = r2.ru_utime.tv_sec - r1.ru_utime.tv_sec; |
| 264 | pt.user_microseconds = r2.ru_utime.tv_usec - r1.ru_utime.tv_usec; |
| 265 | if (pt.user_microseconds < 0) |
| 266 | { |
| 267 | --pt.user_seconds; |
| 268 | pt.user_microseconds += 1000000; |
| 269 | } |
| 270 | |
| 271 | pt.system_seconds = r2.ru_stime.tv_sec - r1.ru_stime.tv_sec; |
| 272 | pt.system_microseconds = r2.ru_stime.tv_usec - r1.ru_stime.tv_usec; |
| 273 | if (pt.system_microseconds < 0) |
| 274 | { |
| 275 | --pt.system_seconds; |
| 276 | pt.system_microseconds += 1000000; |
| 277 | } |
| 278 | } |
| 279 | #endif |
| 280 | |
| 281 | if (cpid < 0 || cpid == pid) |
| 282 | { |
| 283 | if (time != NULL) |
| 284 | *time = pt; |
| 285 | return cpid; |
| 286 | } |
| 287 | |
| 288 | psl = XNEW (struct status_list); |
| 289 | psl->pid = cpid; |
| 290 | psl->status = *status; |
| 291 | if (time != NULL) |
| 292 | psl->time = pt; |
| 293 | psl->next = (struct status_list *) obj->sysdep; |
| 294 | obj->sysdep = (void *) psl; |
| 295 | } |
| 296 | } |
| 297 | |
| 298 | #endif /* ! defined (HAVE_WAITPID) */ |
| 299 | #endif /* ! defined (HAVE_WAIT4) */ |
| 300 | |
| 301 | static void pex_child_error (struct pex_obj *, const char *, const char *, int) |
| 302 | ATTRIBUTE_NORETURN; |
| 303 | static int pex_unix_open_read (struct pex_obj *, const char *, int); |
| 304 | static int pex_unix_open_write (struct pex_obj *, const char *, int, int); |
| 305 | static pid_t pex_unix_exec_child (struct pex_obj *, int, const char *, |
| 306 | char * const *, char * const *, |
| 307 | int, int, int, int, |
| 308 | const char **, int *); |
| 309 | static int pex_unix_close (struct pex_obj *, int); |
| 310 | static int pex_unix_wait (struct pex_obj *, pid_t, int *, struct pex_time *, |
| 311 | int, const char **, int *); |
| 312 | static int pex_unix_pipe (struct pex_obj *, int *, int); |
| 313 | static FILE *pex_unix_fdopenr (struct pex_obj *, int, int); |
| 314 | static FILE *pex_unix_fdopenw (struct pex_obj *, int, int); |
| 315 | static void pex_unix_cleanup (struct pex_obj *); |
| 316 | |
| 317 | /* The list of functions we pass to the common routines. */ |
| 318 | |
| 319 | const struct pex_funcs funcs = |
| 320 | { |
| 321 | pex_unix_open_read, |
| 322 | pex_unix_open_write, |
| 323 | pex_unix_exec_child, |
| 324 | pex_unix_close, |
| 325 | pex_unix_wait, |
| 326 | pex_unix_pipe, |
| 327 | pex_unix_fdopenr, |
| 328 | pex_unix_fdopenw, |
| 329 | pex_unix_cleanup |
| 330 | }; |
| 331 | |
| 332 | /* Return a newly initialized pex_obj structure. */ |
| 333 | |
| 334 | struct pex_obj * |
| 335 | pex_init (int flags, const char *pname, const char *tempbase) |
| 336 | { |
| 337 | return pex_init_common (flags, pname, tempbase, &funcs); |
| 338 | } |
| 339 | |
| 340 | /* Open a file for reading. */ |
| 341 | |
| 342 | static int |
| 343 | pex_unix_open_read (struct pex_obj *obj ATTRIBUTE_UNUSED, const char *name, |
| 344 | int binary ATTRIBUTE_UNUSED) |
| 345 | { |
| 346 | return open (name, O_RDONLY); |
| 347 | } |
| 348 | |
| 349 | /* Open a file for writing. */ |
| 350 | |
| 351 | static int |
| 352 | pex_unix_open_write (struct pex_obj *obj ATTRIBUTE_UNUSED, const char *name, |
| 353 | int binary ATTRIBUTE_UNUSED, int append) |
| 354 | { |
| 355 | /* Note that we can't use O_EXCL here because gcc may have already |
| 356 | created the temporary file via make_temp_file. */ |
| 357 | return open (name, O_WRONLY | O_CREAT |
| 358 | | (append ? O_APPEND : O_TRUNC), PUBLIC_MODE); |
| 359 | } |
| 360 | |
| 361 | /* Close a file. */ |
| 362 | |
| 363 | static int |
| 364 | pex_unix_close (struct pex_obj *obj ATTRIBUTE_UNUSED, int fd) |
| 365 | { |
| 366 | return close (fd); |
| 367 | } |
| 368 | |
| 369 | /* Report an error from a child process. We don't use stdio routines, |
| 370 | because we might be here due to a vfork call. */ |
| 371 | |
| 372 | static void |
| 373 | pex_child_error (struct pex_obj *obj, const char *executable, |
| 374 | const char *errmsg, int err) |
| 375 | { |
| 376 | int retval = 0; |
| 377 | #define writeerr(s) retval |= (write (STDERR_FILE_NO, s, strlen (s)) < 0) |
| 378 | writeerr (obj->pname); |
| 379 | writeerr (": error trying to exec '"); |
| 380 | writeerr (executable); |
| 381 | writeerr ("': "); |
| 382 | writeerr (errmsg); |
| 383 | writeerr (": "); |
| 384 | writeerr (xstrerror (err)); |
| 385 | writeerr ("\n"); |
| 386 | #undef writeerr |
| 387 | /* Exit with -2 if the error output failed, too. */ |
| 388 | _exit (retval == 0 ? -1 : -2); |
| 389 | } |
| 390 | |
| 391 | /* Execute a child. */ |
| 392 | |
| 393 | #if defined(HAVE_SPAWNVE) && defined(HAVE_SPAWNVPE) |
| 394 | /* Implementation of pex->exec_child using the Cygwin spawn operation. */ |
| 395 | |
| 396 | /* Subroutine of pex_unix_exec_child. Move OLD_FD to a new file descriptor |
| 397 | to be stored in *PNEW_FD, save the flags in *PFLAGS, and arrange for the |
| 398 | saved copy to be close-on-exec. Move CHILD_FD into OLD_FD. If CHILD_FD |
| 399 | is -1, OLD_FD is to be closed. Return -1 on error. */ |
| 400 | |
| 401 | static int |
| 402 | save_and_install_fd(int *pnew_fd, int *pflags, int old_fd, int child_fd) |
| 403 | { |
| 404 | int new_fd, flags; |
| 405 | |
| 406 | flags = fcntl (old_fd, F_GETFD); |
| 407 | |
| 408 | /* If we could not retrieve the flags, then OLD_FD was not open. */ |
| 409 | if (flags < 0) |
| 410 | { |
| 411 | new_fd = -1, flags = 0; |
| 412 | if (child_fd >= 0 && dup2 (child_fd, old_fd) < 0) |
| 413 | return -1; |
| 414 | } |
| 415 | /* If we wish to close OLD_FD, just mark it CLOEXEC. */ |
| 416 | else if (child_fd == -1) |
| 417 | { |
| 418 | new_fd = old_fd; |
| 419 | if ((flags & FD_CLOEXEC) == 0 && fcntl (old_fd, F_SETFD, FD_CLOEXEC) < 0) |
| 420 | return -1; |
| 421 | } |
| 422 | /* Otherwise we need to save a copy of OLD_FD before installing CHILD_FD. */ |
| 423 | else |
| 424 | { |
| 425 | #ifdef F_DUPFD_CLOEXEC |
| 426 | new_fd = fcntl (old_fd, F_DUPFD_CLOEXEC, 3); |
| 427 | if (new_fd < 0) |
| 428 | return -1; |
| 429 | #else |
| 430 | /* Prefer F_DUPFD over dup in order to avoid getting a new fd |
| 431 | in the range 0-2, right where a new stderr fd might get put. */ |
| 432 | new_fd = fcntl (old_fd, F_DUPFD, 3); |
| 433 | if (new_fd < 0) |
| 434 | return -1; |
| 435 | if (fcntl (new_fd, F_SETFD, FD_CLOEXEC) < 0) |
| 436 | return -1; |
| 437 | #endif |
| 438 | if (dup2 (child_fd, old_fd) < 0) |
| 439 | return -1; |
| 440 | } |
| 441 | |
| 442 | *pflags = flags; |
| 443 | if (pnew_fd) |
| 444 | *pnew_fd = new_fd; |
| 445 | else if (new_fd != old_fd) |
| 446 | abort (); |
| 447 | |
| 448 | return 0; |
| 449 | } |
| 450 | |
| 451 | /* Subroutine of pex_unix_exec_child. Move SAVE_FD back to OLD_FD |
| 452 | restoring FLAGS. If SAVE_FD < 0, OLD_FD is to be closed. */ |
| 453 | |
| 454 | static int |
| 455 | restore_fd(int old_fd, int save_fd, int flags) |
| 456 | { |
| 457 | /* For SAVE_FD < 0, all we have to do is restore the |
| 458 | "closed-ness" of the original. */ |
| 459 | if (save_fd < 0) |
| 460 | return close (old_fd); |
| 461 | |
| 462 | /* For SAVE_FD == OLD_FD, all we have to do is restore the |
| 463 | original setting of the CLOEXEC flag. */ |
| 464 | if (save_fd == old_fd) |
| 465 | { |
| 466 | if (flags & FD_CLOEXEC) |
| 467 | return 0; |
| 468 | return fcntl (old_fd, F_SETFD, flags); |
| 469 | } |
| 470 | |
| 471 | /* Otherwise we have to move the descriptor back, restore the flags, |
| 472 | and close the saved copy. */ |
| 473 | #ifdef HAVE_DUP3 |
| 474 | if (flags == FD_CLOEXEC) |
| 475 | { |
| 476 | if (dup3 (save_fd, old_fd, O_CLOEXEC) < 0) |
| 477 | return -1; |
| 478 | } |
| 479 | else |
| 480 | #endif |
| 481 | { |
| 482 | if (dup2 (save_fd, old_fd) < 0) |
| 483 | return -1; |
| 484 | if (flags != 0 && fcntl (old_fd, F_SETFD, flags) < 0) |
| 485 | return -1; |
| 486 | } |
| 487 | return close (save_fd); |
| 488 | } |
| 489 | |
| 490 | static pid_t |
| 491 | pex_unix_exec_child (struct pex_obj *obj ATTRIBUTE_UNUSED, |
| 492 | int flags, const char *executable, |
| 493 | char * const * argv, char * const * env, |
| 494 | int in, int out, int errdes, int toclose, |
| 495 | const char **errmsg, int *err) |
| 496 | { |
| 497 | int fl_in = 0, fl_out = 0, fl_err = 0, fl_tc = 0; |
| 498 | int save_in = -1, save_out = -1, save_err = -1; |
| 499 | int max, retries; |
| 500 | pid_t pid; |
| 501 | |
| 502 | if (flags & PEX_STDERR_TO_STDOUT) |
| 503 | errdes = out; |
| 504 | |
| 505 | /* We need the three standard file descriptors to be set up as for |
| 506 | the child before we perform the spawn. The file descriptors for |
| 507 | the parent need to be moved and marked for close-on-exec. */ |
| 508 | if (in != STDIN_FILE_NO |
| 509 | && save_and_install_fd (&save_in, &fl_in, STDIN_FILE_NO, in) < 0) |
| 510 | goto error_dup2; |
| 511 | if (out != STDOUT_FILE_NO |
| 512 | && save_and_install_fd (&save_out, &fl_out, STDOUT_FILE_NO, out) < 0) |
| 513 | goto error_dup2; |
| 514 | if (errdes != STDERR_FILE_NO |
| 515 | && save_and_install_fd (&save_err, &fl_err, STDERR_FILE_NO, errdes) < 0) |
| 516 | goto error_dup2; |
| 517 | if (toclose >= 0 |
| 518 | && save_and_install_fd (NULL, &fl_tc, toclose, -1) < 0) |
| 519 | goto error_dup2; |
| 520 | |
| 521 | /* Now that we've moved the file descriptors for the child into place, |
| 522 | close the originals. Be careful not to close any of the standard |
| 523 | file descriptors that we just set up. */ |
| 524 | max = -1; |
| 525 | if (errdes >= 0) |
| 526 | max = STDERR_FILE_NO; |
| 527 | else if (out >= 0) |
| 528 | max = STDOUT_FILE_NO; |
| 529 | else if (in >= 0) |
| 530 | max = STDIN_FILE_NO; |
| 531 | if (in > max) |
| 532 | close (in); |
| 533 | if (out > max) |
| 534 | close (out); |
| 535 | if (errdes > max && errdes != out) |
| 536 | close (errdes); |
| 537 | |
| 538 | /* If we were not given an environment, use the global environment. */ |
| 539 | if (env == NULL) |
| 540 | env = environ; |
| 541 | |
| 542 | /* Launch the program. If we get EAGAIN (normally out of pid's), try |
| 543 | again a few times with increasing backoff times. */ |
| 544 | retries = 0; |
| 545 | while (1) |
| 546 | { |
| 547 | typedef const char * const *cc_cp; |
| 548 | |
| 549 | if (flags & PEX_SEARCH) |
| 550 | pid = spawnvpe (_P_NOWAITO, executable, (cc_cp)argv, (cc_cp)env); |
| 551 | else |
| 552 | pid = spawnve (_P_NOWAITO, executable, (cc_cp)argv, (cc_cp)env); |
| 553 | |
| 554 | if (pid > 0) |
| 555 | break; |
| 556 | |
| 557 | *err = errno; |
| 558 | *errmsg = "spawn"; |
| 559 | if (errno != EAGAIN || ++retries == 4) |
| 560 | return (pid_t) -1; |
| 561 | sleep (1 << retries); |
| 562 | } |
| 563 | |
| 564 | /* Success. Restore the parent's file descriptors that we saved above. */ |
| 565 | if (toclose >= 0 |
| 566 | && restore_fd (toclose, toclose, fl_tc) < 0) |
| 567 | goto error_dup2; |
| 568 | if (in != STDIN_FILE_NO |
| 569 | && restore_fd (STDIN_FILE_NO, save_in, fl_in) < 0) |
| 570 | goto error_dup2; |
| 571 | if (out != STDOUT_FILE_NO |
| 572 | && restore_fd (STDOUT_FILE_NO, save_out, fl_out) < 0) |
| 573 | goto error_dup2; |
| 574 | if (errdes != STDERR_FILE_NO |
| 575 | && restore_fd (STDERR_FILE_NO, save_err, fl_err) < 0) |
| 576 | goto error_dup2; |
| 577 | |
| 578 | return pid; |
| 579 | |
| 580 | error_dup2: |
| 581 | *err = errno; |
| 582 | *errmsg = "dup2"; |
| 583 | return (pid_t) -1; |
| 584 | } |
| 585 | |
| 586 | #else |
| 587 | /* Implementation of pex->exec_child using standard vfork + exec. */ |
| 588 | |
| 589 | static pid_t |
| 590 | pex_unix_exec_child (struct pex_obj *obj, int flags, const char *executable, |
| 591 | char * const * argv, char * const * env, |
| 592 | int in, int out, int errdes, |
| 593 | int toclose, const char **errmsg, int *err) |
| 594 | { |
| 595 | pid_t pid; |
| 596 | |
| 597 | /* We declare these to be volatile to avoid warnings from gcc about |
| 598 | them being clobbered by vfork. */ |
| 599 | volatile int sleep_interval; |
| 600 | volatile int retries; |
| 601 | |
| 602 | /* We vfork and then set environ in the child before calling execvp. |
| 603 | This clobbers the parent's environ so we need to restore it. |
| 604 | It would be nice to use one of the exec* functions that takes an |
| 605 | environment as a parameter, but that may have portability issues. */ |
| 606 | char **save_environ = environ; |
| 607 | |
| 608 | sleep_interval = 1; |
| 609 | pid = -1; |
| 610 | for (retries = 0; retries < 4; ++retries) |
| 611 | { |
| 612 | pid = vfork (); |
| 613 | if (pid >= 0) |
| 614 | break; |
| 615 | sleep (sleep_interval); |
| 616 | sleep_interval *= 2; |
| 617 | } |
| 618 | |
| 619 | switch (pid) |
| 620 | { |
| 621 | case -1: |
| 622 | *err = errno; |
| 623 | *errmsg = VFORK_STRING; |
| 624 | return (pid_t) -1; |
| 625 | |
| 626 | case 0: |
| 627 | /* Child process. */ |
| 628 | if (in != STDIN_FILE_NO) |
| 629 | { |
| 630 | if (dup2 (in, STDIN_FILE_NO) < 0) |
| 631 | pex_child_error (obj, executable, "dup2", errno); |
| 632 | if (close (in) < 0) |
| 633 | pex_child_error (obj, executable, "close", errno); |
| 634 | } |
| 635 | if (out != STDOUT_FILE_NO) |
| 636 | { |
| 637 | if (dup2 (out, STDOUT_FILE_NO) < 0) |
| 638 | pex_child_error (obj, executable, "dup2", errno); |
| 639 | if (close (out) < 0) |
| 640 | pex_child_error (obj, executable, "close", errno); |
| 641 | } |
| 642 | if (errdes != STDERR_FILE_NO) |
| 643 | { |
| 644 | if (dup2 (errdes, STDERR_FILE_NO) < 0) |
| 645 | pex_child_error (obj, executable, "dup2", errno); |
| 646 | if (close (errdes) < 0) |
| 647 | pex_child_error (obj, executable, "close", errno); |
| 648 | } |
| 649 | if (toclose >= 0) |
| 650 | { |
| 651 | if (close (toclose) < 0) |
| 652 | pex_child_error (obj, executable, "close", errno); |
| 653 | } |
| 654 | if ((flags & PEX_STDERR_TO_STDOUT) != 0) |
| 655 | { |
| 656 | if (dup2 (STDOUT_FILE_NO, STDERR_FILE_NO) < 0) |
| 657 | pex_child_error (obj, executable, "dup2", errno); |
| 658 | } |
| 659 | |
| 660 | if (env) |
| 661 | { |
| 662 | /* NOTE: In a standard vfork implementation this clobbers the |
| 663 | parent's copy of environ "too" (in reality there's only one copy). |
| 664 | This is ok as we restore it below. */ |
| 665 | environ = (char**) env; |
| 666 | } |
| 667 | |
| 668 | if ((flags & PEX_SEARCH) != 0) |
| 669 | { |
| 670 | execvp (executable, to_ptr32 (argv)); |
| 671 | pex_child_error (obj, executable, "execvp", errno); |
| 672 | } |
| 673 | else |
| 674 | { |
| 675 | execv (executable, to_ptr32 (argv)); |
| 676 | pex_child_error (obj, executable, "execv", errno); |
| 677 | } |
| 678 | |
| 679 | /* NOTREACHED */ |
| 680 | return (pid_t) -1; |
| 681 | |
| 682 | default: |
| 683 | /* Parent process. */ |
| 684 | |
| 685 | /* Restore environ. |
| 686 | Note that the parent either doesn't run until the child execs/exits |
| 687 | (standard vfork behaviour), or if it does run then vfork is behaving |
| 688 | more like fork. In either case we needn't worry about clobbering |
| 689 | the child's copy of environ. */ |
| 690 | environ = save_environ; |
| 691 | |
| 692 | if (in != STDIN_FILE_NO) |
| 693 | { |
| 694 | if (close (in) < 0) |
| 695 | { |
| 696 | *err = errno; |
| 697 | *errmsg = "close"; |
| 698 | return (pid_t) -1; |
| 699 | } |
| 700 | } |
| 701 | if (out != STDOUT_FILE_NO) |
| 702 | { |
| 703 | if (close (out) < 0) |
| 704 | { |
| 705 | *err = errno; |
| 706 | *errmsg = "close"; |
| 707 | return (pid_t) -1; |
| 708 | } |
| 709 | } |
| 710 | if (errdes != STDERR_FILE_NO) |
| 711 | { |
| 712 | if (close (errdes) < 0) |
| 713 | { |
| 714 | *err = errno; |
| 715 | *errmsg = "close"; |
| 716 | return (pid_t) -1; |
| 717 | } |
| 718 | } |
| 719 | |
| 720 | return pid; |
| 721 | } |
| 722 | } |
| 723 | #endif /* SPAWN */ |
| 724 | |
| 725 | /* Wait for a child process to complete. */ |
| 726 | |
| 727 | static int |
| 728 | pex_unix_wait (struct pex_obj *obj, pid_t pid, int *status, |
| 729 | struct pex_time *time, int done, const char **errmsg, |
| 730 | int *err) |
| 731 | { |
| 732 | /* If we are cleaning up when the caller didn't retrieve process |
| 733 | status for some reason, encourage the process to go away. */ |
| 734 | if (done) |
| 735 | kill (pid, SIGTERM); |
| 736 | |
| 737 | if (pex_wait (obj, pid, status, time) < 0) |
| 738 | { |
| 739 | *err = errno; |
| 740 | *errmsg = "wait"; |
| 741 | return -1; |
| 742 | } |
| 743 | |
| 744 | return 0; |
| 745 | } |
| 746 | |
| 747 | /* Create a pipe. */ |
| 748 | |
| 749 | static int |
| 750 | pex_unix_pipe (struct pex_obj *obj ATTRIBUTE_UNUSED, int *p, |
| 751 | int binary ATTRIBUTE_UNUSED) |
| 752 | { |
| 753 | return pipe (p); |
| 754 | } |
| 755 | |
| 756 | /* Get a FILE pointer to read from a file descriptor. */ |
| 757 | |
| 758 | static FILE * |
| 759 | pex_unix_fdopenr (struct pex_obj *obj ATTRIBUTE_UNUSED, int fd, |
| 760 | int binary ATTRIBUTE_UNUSED) |
| 761 | { |
| 762 | return fdopen (fd, "r"); |
| 763 | } |
| 764 | |
| 765 | static FILE * |
| 766 | pex_unix_fdopenw (struct pex_obj *obj ATTRIBUTE_UNUSED, int fd, |
| 767 | int binary ATTRIBUTE_UNUSED) |
| 768 | { |
| 769 | if (fcntl (fd, F_SETFD, FD_CLOEXEC) < 0) |
| 770 | return NULL; |
| 771 | return fdopen (fd, "w"); |
| 772 | } |
| 773 | |
| 774 | static void |
| 775 | pex_unix_cleanup (struct pex_obj *obj ATTRIBUTE_UNUSED) |
| 776 | { |
| 777 | #if !defined (HAVE_WAIT4) && !defined (HAVE_WAITPID) |
| 778 | while (obj->sysdep != NULL) |
| 779 | { |
| 780 | struct status_list *this; |
| 781 | struct status_list *next; |
| 782 | |
| 783 | this = (struct status_list *) obj->sysdep; |
| 784 | next = this->next; |
| 785 | free (this); |
| 786 | obj->sysdep = (void *) next; |
| 787 | } |
| 788 | #endif |
| 789 | } |