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00024 #include "dbus-spawn.h"
00025 #include "dbus-sysdeps.h"
00026 #include "dbus-internals.h"
00027 #include "dbus-test.h"
00028 #include "dbus-protocol.h"
00029
00030 #include <unistd.h>
00031 #include <fcntl.h>
00032 #include <signal.h>
00033 #include <sys/wait.h>
00034 #include <errno.h>
00035 #include <stdlib.h>
00036
00042
00043
00044
00045
00046
00050 typedef enum
00051 {
00052 READ_STATUS_OK,
00053 READ_STATUS_ERROR,
00054 READ_STATUS_EOF
00055 } ReadStatus;
00056
00057 static ReadStatus
00058 read_ints (int fd,
00059 int *buf,
00060 int n_ints_in_buf,
00061 int *n_ints_read,
00062 DBusError *error)
00063 {
00064 size_t bytes = 0;
00065 ReadStatus retval;
00066
00067 _DBUS_ASSERT_ERROR_IS_CLEAR (error);
00068
00069 retval = READ_STATUS_OK;
00070
00071 while (TRUE)
00072 {
00073 size_t chunk;
00074 size_t to_read;
00075
00076 to_read = sizeof (int) * n_ints_in_buf - bytes;
00077
00078 if (to_read == 0)
00079 break;
00080
00081 again:
00082
00083 chunk = read (fd,
00084 ((char*)buf) + bytes,
00085 to_read);
00086
00087 if (chunk < 0 && errno == EINTR)
00088 goto again;
00089
00090 if (chunk < 0)
00091 {
00092 dbus_set_error (error,
00093 DBUS_ERROR_SPAWN_FAILED,
00094 "Failed to read from child pipe (%s)",
00095 _dbus_strerror (errno));
00096
00097 retval = READ_STATUS_ERROR;
00098 break;
00099 }
00100 else if (chunk == 0)
00101 {
00102 retval = READ_STATUS_EOF;
00103 break;
00104 }
00105 else
00106 bytes += chunk;
00107 }
00108
00109 *n_ints_read = (int)(bytes / sizeof(int));
00110
00111 return retval;
00112 }
00113
00114 static ReadStatus
00115 read_pid (int fd,
00116 pid_t *buf,
00117 DBusError *error)
00118 {
00119 size_t bytes = 0;
00120 ReadStatus retval;
00121
00122 _DBUS_ASSERT_ERROR_IS_CLEAR (error);
00123
00124 retval = READ_STATUS_OK;
00125
00126 while (TRUE)
00127 {
00128 size_t chunk;
00129 size_t to_read;
00130
00131 to_read = sizeof (pid_t) - bytes;
00132
00133 if (to_read == 0)
00134 break;
00135
00136 again:
00137
00138 chunk = read (fd,
00139 ((char*)buf) + bytes,
00140 to_read);
00141 if (chunk < 0 && errno == EINTR)
00142 goto again;
00143
00144 if (chunk < 0)
00145 {
00146 dbus_set_error (error,
00147 DBUS_ERROR_SPAWN_FAILED,
00148 "Failed to read from child pipe (%s)",
00149 _dbus_strerror (errno));
00150
00151 retval = READ_STATUS_ERROR;
00152 break;
00153 }
00154 else if (chunk == 0)
00155 {
00156 retval = READ_STATUS_EOF;
00157 break;
00158 }
00159 else
00160 bytes += chunk;
00161 }
00162
00163 return retval;
00164 }
00165
00166
00167
00168
00169
00170
00171
00172
00173 enum
00174 {
00175 CHILD_EXITED,
00176 CHILD_FORK_FAILED,
00177 CHILD_EXEC_FAILED,
00178 CHILD_PID
00179 };
00180
00184 struct DBusBabysitter
00185 {
00186 int refcount;
00188 char *executable;
00190 int socket_to_babysitter;
00191 int error_pipe_from_child;
00193 pid_t sitter_pid;
00194 pid_t grandchild_pid;
00196 DBusWatchList *watches;
00198 DBusWatch *error_watch;
00199 DBusWatch *sitter_watch;
00201 int errnum;
00202 int status;
00203 unsigned int have_child_status : 1;
00204 unsigned int have_fork_errnum : 1;
00205 unsigned int have_exec_errnum : 1;
00206 };
00207
00208 static DBusBabysitter*
00209 _dbus_babysitter_new (void)
00210 {
00211 DBusBabysitter *sitter;
00212
00213 sitter = dbus_new0 (DBusBabysitter, 1);
00214 if (sitter == NULL)
00215 return NULL;
00216
00217 sitter->refcount = 1;
00218
00219 sitter->socket_to_babysitter = -1;
00220 sitter->error_pipe_from_child = -1;
00221
00222 sitter->sitter_pid = -1;
00223 sitter->grandchild_pid = -1;
00224
00225 sitter->watches = _dbus_watch_list_new ();
00226 if (sitter->watches == NULL)
00227 goto failed;
00228
00229 return sitter;
00230
00231 failed:
00232 _dbus_babysitter_unref (sitter);
00233 return NULL;
00234 }
00235
00242 DBusBabysitter *
00243 _dbus_babysitter_ref (DBusBabysitter *sitter)
00244 {
00245 _dbus_assert (sitter != NULL);
00246 _dbus_assert (sitter->refcount > 0);
00247
00248 sitter->refcount += 1;
00249
00250 return sitter;
00251 }
00252
00261 void
00262 _dbus_babysitter_unref (DBusBabysitter *sitter)
00263 {
00264 _dbus_assert (sitter != NULL);
00265 _dbus_assert (sitter->refcount > 0);
00266
00267 sitter->refcount -= 1;
00268 if (sitter->refcount == 0)
00269 {
00270 if (sitter->socket_to_babysitter >= 0)
00271 {
00272
00273
00274
00275
00276
00277
00278
00279 _dbus_close (sitter->socket_to_babysitter, NULL);
00280 sitter->socket_to_babysitter = -1;
00281 }
00282
00283 if (sitter->error_pipe_from_child >= 0)
00284 {
00285 _dbus_close (sitter->error_pipe_from_child, NULL);
00286 sitter->error_pipe_from_child = -1;
00287 }
00288
00289 if (sitter->sitter_pid > 0)
00290 {
00291 int status;
00292 int ret;
00293
00294
00295
00296
00297
00298 ret = waitpid (sitter->sitter_pid, &status, WNOHANG);
00299
00300
00301
00302
00303 if (ret == 0)
00304 kill (sitter->sitter_pid, SIGKILL);
00305
00306 again:
00307 if (ret == 0)
00308 ret = waitpid (sitter->sitter_pid, &status, 0);
00309
00310 if (ret < 0)
00311 {
00312 if (errno == EINTR)
00313 goto again;
00314 else if (errno == ECHILD)
00315 _dbus_warn ("Babysitter process not available to be reaped; should not happen\n");
00316 else
00317 _dbus_warn ("Unexpected error %d in waitpid() for babysitter: %s\n",
00318 errno, _dbus_strerror (errno));
00319 }
00320 else
00321 {
00322 _dbus_verbose ("Reaped %ld, waiting for babysitter %ld\n",
00323 (long) ret, (long) sitter->sitter_pid);
00324
00325 if (WIFEXITED (sitter->status))
00326 _dbus_verbose ("Babysitter exited with status %d\n",
00327 WEXITSTATUS (sitter->status));
00328 else if (WIFSIGNALED (sitter->status))
00329 _dbus_verbose ("Babysitter received signal %d\n",
00330 WTERMSIG (sitter->status));
00331 else
00332 _dbus_verbose ("Babysitter exited abnormally\n");
00333 }
00334
00335 sitter->sitter_pid = -1;
00336 }
00337
00338 if (sitter->error_watch)
00339 {
00340 _dbus_watch_invalidate (sitter->error_watch);
00341 _dbus_watch_unref (sitter->error_watch);
00342 sitter->error_watch = NULL;
00343 }
00344
00345 if (sitter->sitter_watch)
00346 {
00347 _dbus_watch_invalidate (sitter->sitter_watch);
00348 _dbus_watch_unref (sitter->sitter_watch);
00349 sitter->sitter_watch = NULL;
00350 }
00351
00352 if (sitter->watches)
00353 _dbus_watch_list_free (sitter->watches);
00354
00355 dbus_free (sitter->executable);
00356
00357 dbus_free (sitter);
00358 }
00359 }
00360
00361 static ReadStatus
00362 read_data (DBusBabysitter *sitter,
00363 int fd)
00364 {
00365 int what;
00366 int got;
00367 DBusError error;
00368 ReadStatus r;
00369
00370 dbus_error_init (&error);
00371
00372 r = read_ints (fd, &what, 1, &got, &error);
00373
00374 switch (r)
00375 {
00376 case READ_STATUS_ERROR:
00377 _dbus_warn ("Failed to read data from fd %d: %s\n", fd, error.message);
00378 dbus_error_free (&error);
00379 return r;
00380
00381 case READ_STATUS_EOF:
00382 return r;
00383
00384 case READ_STATUS_OK:
00385 break;
00386 }
00387
00388 if (got == 1)
00389 {
00390 switch (what)
00391 {
00392 case CHILD_EXITED:
00393 case CHILD_FORK_FAILED:
00394 case CHILD_EXEC_FAILED:
00395 {
00396 int arg;
00397
00398 r = read_ints (fd, &arg, 1, &got, &error);
00399
00400 switch (r)
00401 {
00402 case READ_STATUS_ERROR:
00403 _dbus_warn ("Failed to read arg from fd %d: %s\n", fd, error.message);
00404 dbus_error_free (&error);
00405 return r;
00406 case READ_STATUS_EOF:
00407 return r;
00408 case READ_STATUS_OK:
00409 break;
00410 }
00411
00412 if (got == 1)
00413 {
00414 if (what == CHILD_EXITED)
00415 {
00416 sitter->have_child_status = TRUE;
00417 sitter->status = arg;
00418 _dbus_verbose ("recorded child status exited = %d signaled = %d exitstatus = %d termsig = %d\n",
00419 WIFEXITED (sitter->status), WIFSIGNALED (sitter->status),
00420 WEXITSTATUS (sitter->status), WTERMSIG (sitter->status));
00421 }
00422 else if (what == CHILD_FORK_FAILED)
00423 {
00424 sitter->have_fork_errnum = TRUE;
00425 sitter->errnum = arg;
00426 _dbus_verbose ("recorded fork errnum %d\n", sitter->errnum);
00427 }
00428 else if (what == CHILD_EXEC_FAILED)
00429 {
00430 sitter->have_exec_errnum = TRUE;
00431 sitter->errnum = arg;
00432 _dbus_verbose ("recorded exec errnum %d\n", sitter->errnum);
00433 }
00434 }
00435 }
00436 break;
00437 case CHILD_PID:
00438 {
00439 pid_t pid = -1;
00440
00441 r = read_pid (fd, &pid, &error);
00442
00443 switch (r)
00444 {
00445 case READ_STATUS_ERROR:
00446 _dbus_warn ("Failed to read PID from fd %d: %s\n", fd, error.message);
00447 dbus_error_free (&error);
00448 return r;
00449 case READ_STATUS_EOF:
00450 return r;
00451 case READ_STATUS_OK:
00452 break;
00453 }
00454
00455 sitter->grandchild_pid = pid;
00456
00457 _dbus_verbose ("recorded grandchild pid %d\n", sitter->grandchild_pid);
00458 }
00459 break;
00460 default:
00461 _dbus_warn ("Unknown message received from babysitter process\n");
00462 break;
00463 }
00464 }
00465
00466 return r;
00467 }
00468
00469 static void
00470 close_socket_to_babysitter (DBusBabysitter *sitter)
00471 {
00472 _dbus_verbose ("Closing babysitter\n");
00473 _dbus_close (sitter->socket_to_babysitter, NULL);
00474 sitter->socket_to_babysitter = -1;
00475 }
00476
00477 static void
00478 close_error_pipe_from_child (DBusBabysitter *sitter)
00479 {
00480 _dbus_verbose ("Closing child error\n");
00481 _dbus_close (sitter->error_pipe_from_child, NULL);
00482 sitter->error_pipe_from_child = -1;
00483 }
00484
00485 static void
00486 handle_babysitter_socket (DBusBabysitter *sitter,
00487 int revents)
00488 {
00489
00490
00491
00492
00493 if (revents & _DBUS_POLLIN)
00494 {
00495 _dbus_verbose ("Reading data from babysitter\n");
00496 if (read_data (sitter, sitter->socket_to_babysitter) != READ_STATUS_OK)
00497 close_socket_to_babysitter (sitter);
00498 }
00499 else if (revents & (_DBUS_POLLERR | _DBUS_POLLHUP))
00500 {
00501 close_socket_to_babysitter (sitter);
00502 }
00503 }
00504
00505 static void
00506 handle_error_pipe (DBusBabysitter *sitter,
00507 int revents)
00508 {
00509 if (revents & _DBUS_POLLIN)
00510 {
00511 _dbus_verbose ("Reading data from child error\n");
00512 if (read_data (sitter, sitter->error_pipe_from_child) != READ_STATUS_OK)
00513 close_error_pipe_from_child (sitter);
00514 }
00515 else if (revents & (_DBUS_POLLERR | _DBUS_POLLHUP))
00516 {
00517 close_error_pipe_from_child (sitter);
00518 }
00519 }
00520
00521
00522 static dbus_bool_t
00523 babysitter_iteration (DBusBabysitter *sitter,
00524 dbus_bool_t block)
00525 {
00526 DBusPollFD fds[2];
00527 int i;
00528 dbus_bool_t descriptors_ready;
00529
00530 descriptors_ready = FALSE;
00531
00532 i = 0;
00533
00534 if (sitter->error_pipe_from_child >= 0)
00535 {
00536 fds[i].fd = sitter->error_pipe_from_child;
00537 fds[i].events = _DBUS_POLLIN;
00538 fds[i].revents = 0;
00539 ++i;
00540 }
00541
00542 if (sitter->socket_to_babysitter >= 0)
00543 {
00544 fds[i].fd = sitter->socket_to_babysitter;
00545 fds[i].events = _DBUS_POLLIN;
00546 fds[i].revents = 0;
00547 ++i;
00548 }
00549
00550 if (i > 0)
00551 {
00552 int ret;
00553
00554 ret = _dbus_poll (fds, i, 0);
00555 if (ret == 0 && block)
00556 ret = _dbus_poll (fds, i, -1);
00557
00558 if (ret > 0)
00559 {
00560 descriptors_ready = TRUE;
00561
00562 while (i > 0)
00563 {
00564 --i;
00565 if (fds[i].fd == sitter->error_pipe_from_child)
00566 handle_error_pipe (sitter, fds[i].revents);
00567 else if (fds[i].fd == sitter->socket_to_babysitter)
00568 handle_babysitter_socket (sitter, fds[i].revents);
00569 }
00570 }
00571 }
00572
00573 return descriptors_ready;
00574 }
00575
00580 #define LIVE_CHILDREN(sitter) ((sitter)->socket_to_babysitter >= 0 || (sitter)->error_pipe_from_child >= 0)
00581
00588 void
00589 _dbus_babysitter_kill_child (DBusBabysitter *sitter)
00590 {
00591
00592 while (LIVE_CHILDREN (sitter) &&
00593 sitter->grandchild_pid == -1)
00594 babysitter_iteration (sitter, TRUE);
00595
00596 _dbus_verbose ("Got child PID %ld for killing\n",
00597 (long) sitter->grandchild_pid);
00598
00599 if (sitter->grandchild_pid == -1)
00600 return;
00601
00602 kill (sitter->grandchild_pid, SIGKILL);
00603 }
00604
00610 dbus_bool_t
00611 _dbus_babysitter_get_child_exited (DBusBabysitter *sitter)
00612 {
00613
00614
00615 while (LIVE_CHILDREN (sitter) &&
00616 babysitter_iteration (sitter, FALSE))
00617 ;
00618
00619
00620 return sitter->socket_to_babysitter < 0;
00621 }
00622
00632 void
00633 _dbus_babysitter_set_child_exit_error (DBusBabysitter *sitter,
00634 DBusError *error)
00635 {
00636 if (!_dbus_babysitter_get_child_exited (sitter))
00637 return;
00638
00639
00640
00641
00642
00643 if (sitter->have_exec_errnum)
00644 {
00645 dbus_set_error (error, DBUS_ERROR_SPAWN_EXEC_FAILED,
00646 "Failed to execute program %s: %s",
00647 sitter->executable, _dbus_strerror (sitter->errnum));
00648 }
00649 else if (sitter->have_fork_errnum)
00650 {
00651 dbus_set_error (error, DBUS_ERROR_NO_MEMORY,
00652 "Failed to fork a new process %s: %s",
00653 sitter->executable, _dbus_strerror (sitter->errnum));
00654 }
00655 else if (sitter->have_child_status)
00656 {
00657 if (WIFEXITED (sitter->status))
00658 dbus_set_error (error, DBUS_ERROR_SPAWN_CHILD_EXITED,
00659 "Process %s exited with status %d",
00660 sitter->executable, WEXITSTATUS (sitter->status));
00661 else if (WIFSIGNALED (sitter->status))
00662 dbus_set_error (error, DBUS_ERROR_SPAWN_CHILD_SIGNALED,
00663 "Process %s received signal %d",
00664 sitter->executable, WTERMSIG (sitter->status));
00665 else
00666 dbus_set_error (error, DBUS_ERROR_FAILED,
00667 "Process %s exited abnormally",
00668 sitter->executable);
00669 }
00670 else
00671 {
00672 dbus_set_error (error, DBUS_ERROR_FAILED,
00673 "Process %s exited, reason unknown",
00674 sitter->executable);
00675 }
00676 }
00677
00690 dbus_bool_t
00691 _dbus_babysitter_set_watch_functions (DBusBabysitter *sitter,
00692 DBusAddWatchFunction add_function,
00693 DBusRemoveWatchFunction remove_function,
00694 DBusWatchToggledFunction toggled_function,
00695 void *data,
00696 DBusFreeFunction free_data_function)
00697 {
00698 return _dbus_watch_list_set_functions (sitter->watches,
00699 add_function,
00700 remove_function,
00701 toggled_function,
00702 data,
00703 free_data_function);
00704 }
00705
00706 static dbus_bool_t
00707 handle_watch (DBusWatch *watch,
00708 unsigned int condition,
00709 void *data)
00710 {
00711 DBusBabysitter *sitter = data;
00712 int revents;
00713 int fd;
00714
00715 revents = 0;
00716 if (condition & DBUS_WATCH_READABLE)
00717 revents |= _DBUS_POLLIN;
00718 if (condition & DBUS_WATCH_ERROR)
00719 revents |= _DBUS_POLLERR;
00720 if (condition & DBUS_WATCH_HANGUP)
00721 revents |= _DBUS_POLLHUP;
00722
00723 fd = dbus_watch_get_fd (watch);
00724
00725 if (fd == sitter->error_pipe_from_child)
00726 handle_error_pipe (sitter, revents);
00727 else if (fd == sitter->socket_to_babysitter)
00728 handle_babysitter_socket (sitter, revents);
00729
00730 while (LIVE_CHILDREN (sitter) &&
00731 babysitter_iteration (sitter, FALSE))
00732 ;
00733
00734 return TRUE;
00735 }
00736
00738 #define READ_END 0
00739
00740 #define WRITE_END 1
00741
00742
00743
00744
00745
00746
00747 static int
00748 close_and_invalidate (int *fd)
00749 {
00750 int ret;
00751
00752 if (*fd < 0)
00753 return -1;
00754 else
00755 {
00756 ret = _dbus_close (*fd, NULL);
00757 *fd = -1;
00758 }
00759
00760 return ret;
00761 }
00762
00763 static dbus_bool_t
00764 make_pipe (int p[2],
00765 DBusError *error)
00766 {
00767 _DBUS_ASSERT_ERROR_IS_CLEAR (error);
00768
00769 if (pipe (p) < 0)
00770 {
00771 dbus_set_error (error,
00772 DBUS_ERROR_SPAWN_FAILED,
00773 "Failed to create pipe for communicating with child process (%s)",
00774 _dbus_strerror (errno));
00775 return FALSE;
00776 }
00777
00778 return TRUE;
00779 }
00780
00781 static void
00782 do_write (int fd, const void *buf, size_t count)
00783 {
00784 size_t bytes_written;
00785 int ret;
00786
00787 bytes_written = 0;
00788
00789 again:
00790
00791 ret = write (fd, ((const char*)buf) + bytes_written, count - bytes_written);
00792
00793 if (ret < 0)
00794 {
00795 if (errno == EINTR)
00796 goto again;
00797 else
00798 {
00799 _dbus_warn ("Failed to write data to pipe!\n");
00800 exit (1);
00801 }
00802 }
00803 else
00804 bytes_written += ret;
00805
00806 if (bytes_written < count)
00807 goto again;
00808 }
00809
00810 static void
00811 write_err_and_exit (int fd, int msg)
00812 {
00813 int en = errno;
00814
00815 do_write (fd, &msg, sizeof (msg));
00816 do_write (fd, &en, sizeof (en));
00817
00818 exit (1);
00819 }
00820
00821 static void
00822 write_pid (int fd, pid_t pid)
00823 {
00824 int msg = CHILD_PID;
00825
00826 do_write (fd, &msg, sizeof (msg));
00827 do_write (fd, &pid, sizeof (pid));
00828 }
00829
00830 static void
00831 write_status_and_exit (int fd, int status)
00832 {
00833 int msg = CHILD_EXITED;
00834
00835 do_write (fd, &msg, sizeof (msg));
00836 do_write (fd, &status, sizeof (status));
00837
00838 exit (0);
00839 }
00840
00841 static void
00842 do_exec (int child_err_report_fd,
00843 char **argv,
00844 DBusSpawnChildSetupFunc child_setup,
00845 void *user_data)
00846 {
00847 #ifdef DBUS_BUILD_TESTS
00848 int i, max_open;
00849 #endif
00850
00851 _dbus_verbose_reset ();
00852 _dbus_verbose ("Child process has PID %lu\n",
00853 _dbus_getpid ());
00854
00855 if (child_setup)
00856 (* child_setup) (user_data);
00857
00858 #ifdef DBUS_BUILD_TESTS
00859 max_open = sysconf (_SC_OPEN_MAX);
00860
00861 for (i = 3; i < max_open; i++)
00862 {
00863 int retval;
00864
00865 if (i == child_err_report_fd)
00866 continue;
00867
00868 retval = fcntl (i, F_GETFD);
00869
00870 if (retval != -1 && !(retval & FD_CLOEXEC))
00871 _dbus_warn ("Fd %d did not have the close-on-exec flag set!\n", i);
00872 }
00873 #endif
00874
00875 execv (argv[0], argv);
00876
00877
00878 write_err_and_exit (child_err_report_fd,
00879 CHILD_EXEC_FAILED);
00880 }
00881
00882 static void
00883 check_babysit_events (pid_t grandchild_pid,
00884 int parent_pipe,
00885 int revents)
00886 {
00887 pid_t ret;
00888 int status;
00889
00890 do
00891 {
00892 ret = waitpid (grandchild_pid, &status, WNOHANG);
00893
00894
00895
00896 }
00897 while (ret < 0 && errno == EINTR);
00898
00899 if (ret == 0)
00900 {
00901 _dbus_verbose ("no child exited\n");
00902
00903 ;
00904 }
00905 else if (ret < 0)
00906 {
00907
00908 _dbus_warn ("unexpected waitpid() failure in check_babysit_events(): %s\n",
00909 _dbus_strerror (errno));
00910 exit (1);
00911 }
00912 else if (ret == grandchild_pid)
00913 {
00914
00915 _dbus_verbose ("reaped child pid %ld\n", (long) ret);
00916
00917 write_status_and_exit (parent_pipe, status);
00918 }
00919 else
00920 {
00921 _dbus_warn ("waitpid() reaped pid %d that we've never heard of\n",
00922 (int) ret);
00923 exit (1);
00924 }
00925
00926 if (revents & _DBUS_POLLIN)
00927 {
00928 _dbus_verbose ("babysitter got POLLIN from parent pipe\n");
00929 }
00930
00931 if (revents & (_DBUS_POLLERR | _DBUS_POLLHUP))
00932 {
00933
00934 _dbus_verbose ("babysitter got POLLERR or POLLHUP from parent\n");
00935 exit (0);
00936 }
00937 }
00938
00939 static int babysit_sigchld_pipe = -1;
00940
00941 static void
00942 babysit_signal_handler (int signo)
00943 {
00944 char b = '\0';
00945 again:
00946 write (babysit_sigchld_pipe, &b, 1);
00947 if (errno == EINTR)
00948 goto again;
00949 }
00950
00951 static void
00952 babysit (pid_t grandchild_pid,
00953 int parent_pipe)
00954 {
00955 int sigchld_pipe[2];
00956
00957
00958
00959
00960 _dbus_verbose_reset ();
00961
00962
00963
00964
00965
00966
00967 if (pipe (sigchld_pipe) < 0)
00968 {
00969 _dbus_warn ("Not enough file descriptors to create pipe in babysitter process\n");
00970 exit (1);
00971 }
00972
00973 babysit_sigchld_pipe = sigchld_pipe[WRITE_END];
00974
00975 _dbus_set_signal_handler (SIGCHLD, babysit_signal_handler);
00976
00977 write_pid (parent_pipe, grandchild_pid);
00978
00979 check_babysit_events (grandchild_pid, parent_pipe, 0);
00980
00981 while (TRUE)
00982 {
00983 DBusPollFD pfds[2];
00984
00985 pfds[0].fd = parent_pipe;
00986 pfds[0].events = _DBUS_POLLIN;
00987 pfds[0].revents = 0;
00988
00989 pfds[1].fd = sigchld_pipe[READ_END];
00990 pfds[1].events = _DBUS_POLLIN;
00991 pfds[1].revents = 0;
00992
00993 _dbus_poll (pfds, _DBUS_N_ELEMENTS (pfds), -1);
00994
00995 if (pfds[0].revents != 0)
00996 {
00997 check_babysit_events (grandchild_pid, parent_pipe, pfds[0].revents);
00998 }
00999 else if (pfds[1].revents & _DBUS_POLLIN)
01000 {
01001 char b;
01002 read (sigchld_pipe[READ_END], &b, 1);
01003
01004 check_babysit_events (grandchild_pid, parent_pipe, 0);
01005 }
01006 }
01007
01008 exit (1);
01009 }
01010
01029 dbus_bool_t
01030 _dbus_spawn_async_with_babysitter (DBusBabysitter **sitter_p,
01031 char **argv,
01032 DBusSpawnChildSetupFunc child_setup,
01033 void *user_data,
01034 DBusError *error)
01035 {
01036 DBusBabysitter *sitter;
01037 int child_err_report_pipe[2] = { -1, -1 };
01038 int babysitter_pipe[2] = { -1, -1 };
01039 pid_t pid;
01040
01041 _DBUS_ASSERT_ERROR_IS_CLEAR (error);
01042
01043 *sitter_p = NULL;
01044 sitter = NULL;
01045
01046 sitter = _dbus_babysitter_new ();
01047 if (sitter == NULL)
01048 {
01049 dbus_set_error (error, DBUS_ERROR_NO_MEMORY, NULL);
01050 return FALSE;
01051 }
01052
01053 sitter->executable = _dbus_strdup (argv[0]);
01054 if (sitter->executable == NULL)
01055 {
01056 dbus_set_error (error, DBUS_ERROR_NO_MEMORY, NULL);
01057 goto cleanup_and_fail;
01058 }
01059
01060 if (!make_pipe (child_err_report_pipe, error))
01061 goto cleanup_and_fail;
01062
01063 _dbus_fd_set_close_on_exec (child_err_report_pipe[READ_END]);
01064 _dbus_fd_set_close_on_exec (child_err_report_pipe[WRITE_END]);
01065
01066 if (!_dbus_full_duplex_pipe (&babysitter_pipe[0], &babysitter_pipe[1], TRUE, error))
01067 goto cleanup_and_fail;
01068
01069 _dbus_fd_set_close_on_exec (babysitter_pipe[0]);
01070 _dbus_fd_set_close_on_exec (babysitter_pipe[1]);
01071
01072
01073
01074
01075
01076
01077 sitter->error_watch = _dbus_watch_new (child_err_report_pipe[READ_END],
01078 DBUS_WATCH_READABLE,
01079 TRUE, handle_watch, sitter, NULL);
01080 if (sitter->error_watch == NULL)
01081 {
01082 dbus_set_error (error, DBUS_ERROR_NO_MEMORY, NULL);
01083 goto cleanup_and_fail;
01084 }
01085
01086 if (!_dbus_watch_list_add_watch (sitter->watches, sitter->error_watch))
01087 {
01088 dbus_set_error (error, DBUS_ERROR_NO_MEMORY, NULL);
01089 goto cleanup_and_fail;
01090 }
01091
01092 sitter->sitter_watch = _dbus_watch_new (babysitter_pipe[0],
01093 DBUS_WATCH_READABLE,
01094 TRUE, handle_watch, sitter, NULL);
01095 if (sitter->sitter_watch == NULL)
01096 {
01097 dbus_set_error (error, DBUS_ERROR_NO_MEMORY, NULL);
01098 goto cleanup_and_fail;
01099 }
01100
01101 if (!_dbus_watch_list_add_watch (sitter->watches, sitter->sitter_watch))
01102 {
01103 dbus_set_error (error, DBUS_ERROR_NO_MEMORY, NULL);
01104 goto cleanup_and_fail;
01105 }
01106
01107 _DBUS_ASSERT_ERROR_IS_CLEAR (error);
01108
01109 pid = fork ();
01110
01111 if (pid < 0)
01112 {
01113 dbus_set_error (error,
01114 DBUS_ERROR_SPAWN_FORK_FAILED,
01115 "Failed to fork (%s)",
01116 _dbus_strerror (errno));
01117 goto cleanup_and_fail;
01118 }
01119 else if (pid == 0)
01120 {
01121
01122 int grandchild_pid;
01123
01124
01125
01126
01127 signal (SIGPIPE, SIG_DFL);
01128
01129
01130 close_and_invalidate (&child_err_report_pipe[READ_END]);
01131 close_and_invalidate (&babysitter_pipe[0]);
01132
01133
01134 grandchild_pid = fork ();
01135
01136 if (grandchild_pid < 0)
01137 {
01138 write_err_and_exit (babysitter_pipe[1],
01139 CHILD_FORK_FAILED);
01140 _dbus_assert_not_reached ("Got to code after write_err_and_exit()");
01141 }
01142 else if (grandchild_pid == 0)
01143 {
01144 do_exec (child_err_report_pipe[WRITE_END],
01145 argv,
01146 child_setup, user_data);
01147 _dbus_assert_not_reached ("Got to code after exec() - should have exited on error");
01148 }
01149 else
01150 {
01151 babysit (grandchild_pid, babysitter_pipe[1]);
01152 _dbus_assert_not_reached ("Got to code after babysit()");
01153 }
01154 }
01155 else
01156 {
01157
01158 close_and_invalidate (&child_err_report_pipe[WRITE_END]);
01159 close_and_invalidate (&babysitter_pipe[1]);
01160
01161 sitter->socket_to_babysitter = babysitter_pipe[0];
01162 babysitter_pipe[0] = -1;
01163
01164 sitter->error_pipe_from_child = child_err_report_pipe[READ_END];
01165 child_err_report_pipe[READ_END] = -1;
01166
01167 sitter->sitter_pid = pid;
01168
01169 if (sitter_p != NULL)
01170 *sitter_p = sitter;
01171 else
01172 _dbus_babysitter_unref (sitter);
01173
01174 _DBUS_ASSERT_ERROR_IS_CLEAR (error);
01175
01176 return TRUE;
01177 }
01178
01179 cleanup_and_fail:
01180
01181 _DBUS_ASSERT_ERROR_IS_SET (error);
01182
01183 close_and_invalidate (&child_err_report_pipe[READ_END]);
01184 close_and_invalidate (&child_err_report_pipe[WRITE_END]);
01185 close_and_invalidate (&babysitter_pipe[0]);
01186 close_and_invalidate (&babysitter_pipe[1]);
01187
01188 if (sitter != NULL)
01189 _dbus_babysitter_unref (sitter);
01190
01191 return FALSE;
01192 }
01193
01196 #ifdef DBUS_BUILD_TESTS
01197
01198 static void
01199 _dbus_babysitter_block_for_child_exit (DBusBabysitter *sitter)
01200 {
01201 while (LIVE_CHILDREN (sitter))
01202 babysitter_iteration (sitter, TRUE);
01203 }
01204
01205 static dbus_bool_t
01206 check_spawn_nonexistent (void *data)
01207 {
01208 char *argv[4] = { NULL, NULL, NULL, NULL };
01209 DBusBabysitter *sitter;
01210 DBusError error;
01211
01212 sitter = NULL;
01213
01214 dbus_error_init (&error);
01215
01216
01217
01218 argv[0] = "/this/does/not/exist/32542sdgafgafdg";
01219 if (_dbus_spawn_async_with_babysitter (&sitter, argv,
01220 NULL, NULL,
01221 &error))
01222 {
01223 _dbus_babysitter_block_for_child_exit (sitter);
01224 _dbus_babysitter_set_child_exit_error (sitter, &error);
01225 }
01226
01227 if (sitter)
01228 _dbus_babysitter_unref (sitter);
01229
01230 if (!dbus_error_is_set (&error))
01231 {
01232 _dbus_warn ("Did not get an error launching nonexistent executable\n");
01233 return FALSE;
01234 }
01235
01236 if (!(dbus_error_has_name (&error, DBUS_ERROR_NO_MEMORY) ||
01237 dbus_error_has_name (&error, DBUS_ERROR_SPAWN_EXEC_FAILED)))
01238 {
01239 _dbus_warn ("Not expecting error when launching nonexistent executable: %s: %s\n",
01240 error.name, error.message);
01241 dbus_error_free (&error);
01242 return FALSE;
01243 }
01244
01245 dbus_error_free (&error);
01246
01247 return TRUE;
01248 }
01249
01250 static dbus_bool_t
01251 check_spawn_segfault (void *data)
01252 {
01253 char *argv[4] = { NULL, NULL, NULL, NULL };
01254 DBusBabysitter *sitter;
01255 DBusError error;
01256
01257 sitter = NULL;
01258
01259 dbus_error_init (&error);
01260
01261
01262
01263 argv[0] = TEST_SEGFAULT_BINARY;
01264 if (_dbus_spawn_async_with_babysitter (&sitter, argv,
01265 NULL, NULL,
01266 &error))
01267 {
01268 _dbus_babysitter_block_for_child_exit (sitter);
01269 _dbus_babysitter_set_child_exit_error (sitter, &error);
01270 }
01271
01272 if (sitter)
01273 _dbus_babysitter_unref (sitter);
01274
01275 if (!dbus_error_is_set (&error))
01276 {
01277 _dbus_warn ("Did not get an error launching segfaulting binary\n");
01278 return FALSE;
01279 }
01280
01281 if (!(dbus_error_has_name (&error, DBUS_ERROR_NO_MEMORY) ||
01282 dbus_error_has_name (&error, DBUS_ERROR_SPAWN_CHILD_SIGNALED)))
01283 {
01284 _dbus_warn ("Not expecting error when launching segfaulting executable: %s: %s\n",
01285 error.name, error.message);
01286 dbus_error_free (&error);
01287 return FALSE;
01288 }
01289
01290 dbus_error_free (&error);
01291
01292 return TRUE;
01293 }
01294
01295 static dbus_bool_t
01296 check_spawn_exit (void *data)
01297 {
01298 char *argv[4] = { NULL, NULL, NULL, NULL };
01299 DBusBabysitter *sitter;
01300 DBusError error;
01301
01302 sitter = NULL;
01303
01304 dbus_error_init (&error);
01305
01306
01307
01308 argv[0] = TEST_EXIT_BINARY;
01309 if (_dbus_spawn_async_with_babysitter (&sitter, argv,
01310 NULL, NULL,
01311 &error))
01312 {
01313 _dbus_babysitter_block_for_child_exit (sitter);
01314 _dbus_babysitter_set_child_exit_error (sitter, &error);
01315 }
01316
01317 if (sitter)
01318 _dbus_babysitter_unref (sitter);
01319
01320 if (!dbus_error_is_set (&error))
01321 {
01322 _dbus_warn ("Did not get an error launching binary that exited with failure code\n");
01323 return FALSE;
01324 }
01325
01326 if (!(dbus_error_has_name (&error, DBUS_ERROR_NO_MEMORY) ||
01327 dbus_error_has_name (&error, DBUS_ERROR_SPAWN_CHILD_EXITED)))
01328 {
01329 _dbus_warn ("Not expecting error when launching exiting executable: %s: %s\n",
01330 error.name, error.message);
01331 dbus_error_free (&error);
01332 return FALSE;
01333 }
01334
01335 dbus_error_free (&error);
01336
01337 return TRUE;
01338 }
01339
01340 static dbus_bool_t
01341 check_spawn_and_kill (void *data)
01342 {
01343 char *argv[4] = { NULL, NULL, NULL, NULL };
01344 DBusBabysitter *sitter;
01345 DBusError error;
01346
01347 sitter = NULL;
01348
01349 dbus_error_init (&error);
01350
01351
01352
01353 argv[0] = TEST_SLEEP_FOREVER_BINARY;
01354 if (_dbus_spawn_async_with_babysitter (&sitter, argv,
01355 NULL, NULL,
01356 &error))
01357 {
01358 _dbus_babysitter_kill_child (sitter);
01359
01360 _dbus_babysitter_block_for_child_exit (sitter);
01361
01362 _dbus_babysitter_set_child_exit_error (sitter, &error);
01363 }
01364
01365 if (sitter)
01366 _dbus_babysitter_unref (sitter);
01367
01368 if (!dbus_error_is_set (&error))
01369 {
01370 _dbus_warn ("Did not get an error after killing spawned binary\n");
01371 return FALSE;
01372 }
01373
01374 if (!(dbus_error_has_name (&error, DBUS_ERROR_NO_MEMORY) ||
01375 dbus_error_has_name (&error, DBUS_ERROR_SPAWN_CHILD_SIGNALED)))
01376 {
01377 _dbus_warn ("Not expecting error when killing executable: %s: %s\n",
01378 error.name, error.message);
01379 dbus_error_free (&error);
01380 return FALSE;
01381 }
01382
01383 dbus_error_free (&error);
01384
01385 return TRUE;
01386 }
01387
01388 dbus_bool_t
01389 _dbus_spawn_test (const char *test_data_dir)
01390 {
01391 if (!_dbus_test_oom_handling ("spawn_nonexistent",
01392 check_spawn_nonexistent,
01393 NULL))
01394 return FALSE;
01395
01396 if (!_dbus_test_oom_handling ("spawn_segfault",
01397 check_spawn_segfault,
01398 NULL))
01399 return FALSE;
01400
01401 if (!_dbus_test_oom_handling ("spawn_exit",
01402 check_spawn_exit,
01403 NULL))
01404 return FALSE;
01405
01406 if (!_dbus_test_oom_handling ("spawn_and_kill",
01407 check_spawn_and_kill,
01408 NULL))
01409 return FALSE;
01410
01411 return TRUE;
01412 }
01413 #endif