27 #if defined(DBUS_WIN) || !defined(DBUS_UNIX) 28 #error "This file only makes sense on Unix OSs" 31 #include "dbus-spawn.h" 32 #include "dbus-sysdeps-unix.h" 33 #include "dbus-internals.h" 34 #include "dbus-test.h" 35 #include "dbus-protocol.h" 50 #include <systemd/sd-journal.h> 53 #if defined(__APPLE__) 54 # include <crt_externs.h> 55 # define environ (*_NSGetEnviron ()) 56 #elif !HAVE_DECL_ENVIRON 57 extern char **environ;
90 _DBUS_ASSERT_ERROR_IS_CLEAR (error);
99 to_read =
sizeof (int) * n_ints_in_buf - bytes;
107 ((
char*)buf) + bytes,
110 if (chunk < 0 && errno == EINTR)
117 "Failed to read from child pipe (%s)",
118 _dbus_strerror (errno));
132 *n_ints_read = (int)(bytes /
sizeof(
int));
145 _DBUS_ASSERT_ERROR_IS_CLEAR (error);
154 to_read =
sizeof (pid_t) - bytes;
162 ((
char*)buf) + bytes,
164 if (chunk < 0 && errno == EINTR)
171 "Failed to read from child pipe (%s)",
172 _dbus_strerror (errno));
267 DBusBabysitterFinishedFunc finished_cb;
278 _dbus_babysitter_new (
void)
349 close_socket_to_babysitter (sitter);
351 close_error_pipe_from_child (sitter);
362 ret = waitpid (sitter->
sitter_pid, &status, WNOHANG);
374 ret = waitpid (sitter->
sitter_pid, &status, 0);
376 while (_DBUS_UNLIKELY (ret < 0 && errno == EINTR));
382 _dbus_warn (
"Babysitter process not available to be reaped; should not happen");
384 _dbus_warn (
"Unexpected error %d in waitpid() for babysitter: %s",
385 errno, _dbus_strerror (errno));
389 _dbus_verbose (
"Reaped %ld, waiting for babysitter %ld\n",
392 if (WIFEXITED (sitter->
status))
393 _dbus_verbose (
"Babysitter exited with status %d\n",
394 WEXITSTATUS (sitter->
status));
395 else if (WIFSIGNALED (sitter->
status))
396 _dbus_verbose (
"Babysitter received signal %d\n",
397 WTERMSIG (sitter->
status));
399 _dbus_verbose (
"Babysitter exited abnormally\n");
423 r = read_ints (fd, &what, 1, &got, &error);
448 case CHILD_FORK_FAILED:
449 case CHILD_EXEC_FAILED:
453 r = read_ints (fd, &arg, 1, &got, &error);
472 if (what == CHILD_EXITED)
493 _dbus_verbose (
"recorded child status exited = %d signaled = %d exitstatus = %d termsig = %d\n",
494 WIFEXITED (sitter->
status), WIFSIGNALED (sitter->
status),
495 WEXITSTATUS (sitter->
status), WTERMSIG (sitter->
status));
497 else if (what == CHILD_FORK_FAILED)
501 _dbus_verbose (
"recorded fork errnum %d\n", sitter->
errnum);
503 else if (what == CHILD_EXEC_FAILED)
507 _dbus_verbose (
"recorded exec errnum %d\n", sitter->
errnum);
516 r = read_pid (fd, &pid, &error);
535 _dbus_verbose (
"recorded grandchild pid %d\n", sitter->
grandchild_pid);
539 _dbus_warn (
"Unknown message received from babysitter process");
550 _dbus_verbose (
"Closing babysitter\n");
571 _dbus_verbose (
"Closing child error\n");
599 _dbus_verbose (
"Reading data from babysitter\n");
601 close_socket_to_babysitter (sitter);
605 close_socket_to_babysitter (sitter);
615 _dbus_verbose (
"Reading data from child error\n");
617 close_error_pipe_from_child (sitter);
621 close_error_pipe_from_child (sitter);
634 descriptors_ready =
FALSE;
662 while (ret < 0 && errno == EINTR);
664 if (ret == 0 && block)
670 while (ret < 0 && errno == EINTR);
675 descriptors_ready =
TRUE;
681 handle_error_pipe (sitter, fds[i].revents);
683 handle_babysitter_socket (sitter, fds[i].revents);
688 return descriptors_ready;
695 #define LIVE_CHILDREN(sitter) ((sitter)->socket_to_babysitter.fd >= 0 || (sitter)->error_pipe_from_child >= 0) 709 babysitter_iteration (sitter,
TRUE);
711 _dbus_verbose (
"Got child PID %ld for killing\n",
731 babysitter_iteration (sitter,
FALSE))
758 !(WIFEXITED (sitter->
status)))
761 *status = WEXITSTATUS (sitter->
status);
788 "Failed to execute program %s: %s",
794 "Failed to fork a new process %s: %s",
799 if (WIFEXITED (sitter->
status))
801 "Process %s exited with status %d",
803 else if (WIFSIGNALED (sitter->
status))
805 "Process %s received signal %d",
809 "Process %s exited abnormally",
815 "Process %s exited, reason unknown",
850 unsigned int condition,
868 handle_error_pipe (sitter, revents);
870 handle_babysitter_socket (sitter, revents);
873 babysitter_iteration (sitter,
FALSE))
882 sitter->finished_cb !=
NULL)
884 sitter->finished_cb (sitter, sitter->finished_data);
885 sitter->finished_cb =
NULL;
908 close_and_invalidate (
int *fd)
932 retval = pipe2 (p, O_CLOEXEC);
933 cloexec_done = retval >= 0;
937 if (retval < 0 && errno == ENOSYS)
943 _DBUS_ASSERT_ERROR_IS_CLEAR (error);
949 "Failed to create pipe for communicating with child process (%s)",
950 _dbus_strerror (errno));
966 do_write (
int fd,
const void *buf,
size_t count)
968 size_t bytes_written;
975 ret = write (fd, ((
const char*)buf) + bytes_written, count - bytes_written);
988 bytes_written += ret;
990 if (bytes_written < count)
994 static void write_err_and_exit (
int fd,
int msg) _DBUS_GNUC_NORETURN;
997 write_err_and_exit (
int fd,
int msg)
1001 do_write (fd, &msg,
sizeof (msg));
1002 do_write (fd, &en,
sizeof (en));
1008 write_pid (
int fd, pid_t pid)
1010 int msg = CHILD_PID;
1012 do_write (fd, &msg,
sizeof (msg));
1013 do_write (fd, &pid,
sizeof (pid));
1016 static void write_status_and_exit (
int fd,
int status) _DBUS_GNUC_NORETURN;
1019 write_status_and_exit (
int fd,
int status)
1021 int msg = CHILD_EXITED;
1023 do_write (fd, &msg,
sizeof (msg));
1024 do_write (fd, &status,
sizeof (status));
1029 static void do_exec (
int child_err_report_fd,
1032 DBusSpawnChildSetupFunc child_setup,
1033 void *user_data) _DBUS_GNUC_NORETURN;
1036 do_exec (
int child_err_report_fd,
1039 DBusSpawnChildSetupFunc child_setup,
1042 #ifdef DBUS_ENABLE_EMBEDDED_TESTS 1046 _dbus_verbose_reset ();
1051 (* child_setup) (user_data);
1053 #ifdef DBUS_ENABLE_EMBEDDED_TESTS 1054 max_open = sysconf (_SC_OPEN_MAX);
1056 for (i = 3; i < max_open; i++)
1060 if (i == child_err_report_fd)
1063 retval = fcntl (i, F_GETFD);
1065 if (retval != -1 && !(retval & FD_CLOEXEC))
1066 _dbus_warn (
"Fd %d did not have the close-on-exec flag set!", i);
1077 execve (argv[0], argv, envp);
1080 write_err_and_exit (child_err_report_fd,
1099 while (ret < 0 && errno == EINTR);
1103 _dbus_verbose (
"no child exited\n");
1110 _dbus_warn (
"unexpected waitpid() failure in check_babysit_events(): %s",
1111 _dbus_strerror (errno));
1117 _dbus_verbose (
"reaped child pid %ld\n", (
long) ret);
1119 write_status_and_exit (parent_pipe, status);
1123 _dbus_warn (
"waitpid() reaped pid %d that we've never heard of",
1130 _dbus_verbose (
"babysitter got POLLIN from parent pipe\n");
1136 _dbus_verbose (
"babysitter got POLLERR or POLLHUP from parent\n");
1141 static int babysit_sigchld_pipe = -1;
1144 babysit_signal_handler (
int signo)
1148 int saved_errno = errno;
1152 if (write (babysit_sigchld_pipe, &b, 1) <= 0)
1156 errno = saved_errno;
1160 int parent_pipe) _DBUS_GNUC_NORETURN;
1166 int sigchld_pipe[2];
1171 _dbus_verbose_reset ();
1178 if (pipe (sigchld_pipe) < 0)
1180 _dbus_warn (
"Not enough file descriptors to create pipe in babysitter process");
1184 babysit_sigchld_pipe = sigchld_pipe[
WRITE_END];
1196 pfds[0].
fd = parent_pipe;
1206 _dbus_warn (
"_dbus_poll() error: %s", strerror (errno));
1210 if (pfds[0].revents != 0)
1212 check_babysit_events (
grandchild_pid, parent_pipe, pfds[0].revents);
1217 if (read (sigchld_pipe[
READ_END], &b, 1) == -1)
1258 DBusSpawnFlags flags,
1259 DBusSpawnChildSetupFunc child_setup,
1264 int child_err_report_pipe[2] = { -1, -1 };
1265 DBusSocket babysitter_pipe[2] = { DBUS_SOCKET_INIT, DBUS_SOCKET_INIT };
1270 _DBUS_ASSERT_ERROR_IS_CLEAR (error);
1273 if (sitter_p !=
NULL)
1278 sitter = _dbus_babysitter_new ();
1289 goto cleanup_and_fail;
1298 goto cleanup_and_fail;
1301 if (!make_pipe (child_err_report_pipe, error))
1302 goto cleanup_and_fail;
1305 goto cleanup_and_fail;
1318 goto cleanup_and_fail;
1330 goto cleanup_and_fail;
1339 goto cleanup_and_fail;
1351 goto cleanup_and_fail;
1354 _DBUS_ASSERT_ERROR_IS_CLEAR (error);
1356 if (flags & DBUS_SPAWN_SILENCE_OUTPUT)
1358 fd_out = open (
"/dev/null", O_RDONLY);
1363 "Failed to open /dev/null: %s",
1364 _dbus_strerror (errno));
1365 goto cleanup_and_fail;
1373 goto cleanup_and_fail;
1376 else if (flags & DBUS_SPAWN_REDIRECT_OUTPUT)
1382 fd_out = sd_journal_stream_fd (sitter->
log_name, LOG_INFO,
FALSE);
1383 fd_err = sd_journal_stream_fd (sitter->
log_name, LOG_WARNING,
FALSE);
1398 "Failed to fork (%s)",
1399 _dbus_strerror (errno));
1400 goto cleanup_and_fail;
1410 signal (SIGPIPE, SIG_DFL);
1413 close_and_invalidate (&child_err_report_pipe[READ_END]);
1414 close_and_invalidate (&babysitter_pipe[0].fd);
1420 grandchild_pid = fork ();
1422 if (grandchild_pid < 0)
1424 write_err_and_exit (babysitter_pipe[1].fd,
1428 else if (grandchild_pid == 0)
1434 fd = open (
"/proc/self/oom_score_adj", O_WRONLY | O_CLOEXEC);
1439 fd = open (
"/proc/self/oom_score_adj", O_WRONLY);
1445 if (write (fd,
"0",
sizeof (
char)) < 0)
1446 _dbus_warn (
"writing oom_score_adj error: %s", strerror (errno));
1452 signal (SIGPIPE, SIG_IGN);
1454 close_and_invalidate (&babysitter_pipe[1].fd);
1459 dup2 (fd_out, STDOUT_FILENO);
1461 dup2 (fd_err, STDERR_FILENO);
1462 close_and_invalidate (&fd_out);
1463 close_and_invalidate (&fd_err);
1465 do_exec (child_err_report_pipe[
WRITE_END],
1468 child_setup, user_data);
1473 close_and_invalidate (&child_err_report_pipe[
WRITE_END]);
1474 close_and_invalidate (&fd_out);
1475 close_and_invalidate (&fd_err);
1476 babysit (grandchild_pid, babysitter_pipe[1].fd);
1483 close_and_invalidate (&child_err_report_pipe[
WRITE_END]);
1484 close_and_invalidate (&babysitter_pipe[1].fd);
1485 close_and_invalidate (&fd_out);
1486 close_and_invalidate (&fd_err);
1489 babysitter_pipe[0].fd = -1;
1492 child_err_report_pipe[
READ_END] = -1;
1496 if (sitter_p !=
NULL)
1503 _DBUS_ASSERT_ERROR_IS_CLEAR (error);
1510 _DBUS_ASSERT_ERROR_IS_SET (error);
1512 close_and_invalidate (&child_err_report_pipe[READ_END]);
1513 close_and_invalidate (&child_err_report_pipe[
WRITE_END]);
1514 close_and_invalidate (&babysitter_pipe[0].fd);
1515 close_and_invalidate (&babysitter_pipe[1].fd);
1516 close_and_invalidate (&fd_out);
1517 close_and_invalidate (&fd_err);
1527 DBusBabysitterFinishedFunc finished,
1530 sitter->finished_cb = finished;
1531 sitter->finished_data = user_data;
1540 babysitter_iteration (sitter,
TRUE);
const char * message
public error message field
#define DBUS_ERROR_SPAWN_FAILED
While starting a new process, something went wrong.
DBusWatch * _dbus_watch_new(DBusPollable fd, unsigned int flags, dbus_bool_t enabled, DBusWatchHandler handler, void *data, DBusFreeFunction free_data_function)
Creates a new DBusWatch.
Implementation of DBusWatch.
#define NULL
A null pointer, defined appropriately for C or C++.
#define DBUS_ERROR_SPAWN_EXEC_FAILED
While starting a new process, the exec() call failed.
void(* DBusFreeFunction)(void *memory)
The type of a function which frees a block of memory.
#define LIVE_CHILDREN(sitter)
Macro returns TRUE if the babysitter still has live sockets open to the babysitter child or the grand...
#define _DBUS_POLLHUP
Hung up.
unsigned int have_exec_errnum
True if we have an error code from exec()
void dbus_free(void *memory)
Frees a block of memory previously allocated by dbus_malloc() or dbus_malloc0().
DBusWatch * error_watch
Error pipe watch.
dbus_bool_t _dbus_socketpair(DBusSocket *fd1, DBusSocket *fd2, dbus_bool_t blocking, DBusError *error)
Creates pair of connect sockets (as in socketpair()).
#define DBUS_PID_FORMAT
an appropriate printf format for dbus_pid_t
void(* DBusWatchToggledFunction)(DBusWatch *watch, void *data)
Called when dbus_watch_get_enabled() may return a different value than it did before.
#define DBUS_ERROR_SPAWN_CHILD_EXITED
While starting a new process, the child exited with a status code.
int status
Exit status code.
#define _dbus_assert(condition)
Aborts with an error message if the condition is false.
#define DBUS_ERROR_INIT
Expands to a suitable initializer for a DBusError on the stack.
void dbus_error_free(DBusError *error)
Frees an error that's been set (or just initialized), then reinitializes the error as in dbus_error_i...
void _dbus_watch_list_free(DBusWatchList *watch_list)
Frees a DBusWatchList.
dbus_pid_t _dbus_getpid(void)
Gets our process ID.
#define _DBUS_POLLIN
There is data to read.
DBusWatchList * _dbus_watch_list_new(void)
Creates a new watch list.
int _dbus_dup(int fd, DBusError *error)
Duplicates a file descriptor.
short events
Events to poll for.
dbus_bool_t _dbus_close_socket(DBusSocket fd, DBusError *error)
Closes a socket.
dbus_bool_t _dbus_babysitter_get_child_exited(DBusBabysitter *sitter)
Checks whether the child has exited, without blocking.
const char * _dbus_error_from_errno(int error_number)
Converts a UNIX errno, or Windows errno or WinSock error value into a DBusError name.
dbus_bool_t _dbus_watch_list_set_functions(DBusWatchList *watch_list, DBusAddWatchFunction add_function, DBusRemoveWatchFunction remove_function, DBusWatchToggledFunction toggled_function, void *data, DBusFreeFunction free_data_function)
Sets the watch functions.
void _dbus_set_signal_handler(int sig, DBusSignalHandler handler)
Installs a UNIX signal handler.
DBusWatchList * watches
Watches.
#define DBUS_ERROR_SPAWN_CHILD_SIGNALED
While starting a new process, the child exited on a signal.
#define dbus_new0(type, count)
Safe macro for using dbus_malloc0().
dbus_uint32_t dbus_bool_t
A boolean, valid values are TRUE and FALSE.
DBusWatch * sitter_watch
Sitter pipe watch.
DBUS_EXPORT int dbus_watch_get_socket(DBusWatch *watch)
Returns a socket to be watched, on UNIX this will return -1 if our transport is not socket-based so d...
dbus_bool_t _dbus_babysitter_get_child_exit_status(DBusBabysitter *sitter, int *status)
Gets the exit status of the child.
void _dbus_babysitter_kill_child(DBusBabysitter *sitter)
Blocks until the babysitter process gives us the PID of the spawned grandchild, then kills the spawne...
Babysitter implementation details.
ReadStatus
Enumeration for status of a read()
void _dbus_warn(const char *format,...)
Prints a warning message to stderr.
pid_t sitter_pid
PID Of the babysitter.
dbus_bool_t _dbus_spawn_async_with_babysitter(DBusBabysitter **sitter_p, const char *log_name, char *const *argv, char **env, DBusSpawnFlags flags, DBusSpawnChildSetupFunc child_setup, void *user_data, DBusError *error)
Spawns a new process.
void _dbus_watch_invalidate(DBusWatch *watch)
Clears the file descriptor from a now-invalid watch object so that no one tries to use it...
dbus_bool_t _dbus_babysitter_set_watch_functions(DBusBabysitter *sitter, DBusAddWatchFunction add_function, DBusRemoveWatchFunction remove_function, DBusWatchToggledFunction toggled_function, void *data, DBusFreeFunction free_data_function)
Sets watch functions to notify us when the babysitter object needs to read/write file descriptors...
Object representing an exception.
void dbus_set_error(DBusError *error, const char *name, const char *format,...)
Assigns an error name and message to a DBusError.
pid_t grandchild_pid
PID of the grandchild.
#define _DBUS_N_ELEMENTS(array)
Computes the number of elements in a fixed-size array using sizeof().
int refcount
Reference count.
unsigned int have_child_status
True if child status has been reaped.
As in POLLERR (can't watch for this, but can be present in current state passed to dbus_watch_handle(...
#define TRUE
Expands to "1".
DBusPollable fd
File descriptor.
#define _dbus_assert_not_reached(explanation)
Aborts with an error message if called.
As in POLLHUP (can't watch for it, but can be present in current state passed to dbus_watch_handle())...
#define DBUS_ERROR_FAILED
A generic error; "something went wrong" - see the error message for more.
dbus_bool_t _dbus_watch_list_add_watch(DBusWatchList *watch_list, DBusWatch *watch)
Adds a new watch to the watch list, invoking the application DBusAddWatchFunction if appropriate...
dbus_bool_t(* DBusAddWatchFunction)(DBusWatch *watch, void *data)
Called when libdbus needs a new watch to be monitored by the main loop.
#define READ_END
Helps remember which end of the pipe is which.
void(* DBusRemoveWatchFunction)(DBusWatch *watch, void *data)
Called when libdbus no longer needs a watch to be monitored by the main loop.
DBusWatchList implementation details.
void _dbus_fd_set_close_on_exec(int fd)
Sets the file descriptor to be close on exec.
void _dbus_watch_list_remove_watch(DBusWatchList *watch_list, DBusWatch *watch)
Removes a watch from the watch list, invoking the application's DBusRemoveWatchFunction if appropriat...
void _dbus_babysitter_unref(DBusBabysitter *sitter)
Decrement the reference count on the babysitter object.
#define DBUS_ERROR_SPAWN_FORK_FAILED
While starting a new process, the fork() call failed.
void dbus_free_string_array(char **str_array)
Frees a NULL-terminated array of strings.
char * log_name
the name under which to log messages about this process being spawned
void _dbus_watch_unref(DBusWatch *watch)
Decrements the reference count of a DBusWatch object and finalizes the object if the count reaches ze...
#define DBUS_ERROR_NO_MEMORY
There was not enough memory to complete an operation.
dbus_bool_t _dbus_close(int fd, DBusError *error)
Closes a file descriptor.
unsigned int have_fork_errnum
True if we have an error code from fork()
#define FALSE
Expands to "0".
int error_pipe_from_child
Connection to the process that does the exec()
DBusSocket socket_to_babysitter
Connection to the babysitter process.
#define WRITE_END
Helps remember which end of the pipe is which.
char * _dbus_strdup(const char *str)
Duplicates a string.
void _dbus_babysitter_set_child_exit_error(DBusBabysitter *sitter, DBusError *error)
Sets the DBusError with an explanation of why the spawned child process exited (on a signal...
int _dbus_poll(DBusPollFD *fds, int n_fds, int timeout_milliseconds)
Wrapper for poll().
short revents
Events that occurred.
#define _DBUS_POLLERR
Error condition.
DBusBabysitter * _dbus_babysitter_ref(DBusBabysitter *sitter)
Increment the reference count on the babysitter object.