27 #include "dbus-spawn.h" 28 #include "dbus-sysdeps-unix.h" 29 #include "dbus-internals.h" 30 #include "dbus-test.h" 31 #include "dbus-protocol.h" 45 #include <systemd/sd-journal.h> 48 #if defined(__APPLE__) 49 # include <crt_externs.h> 50 # define environ (*_NSGetEnviron ()) 51 #elif !HAVE_DECL_ENVIRON 52 extern char **environ;
85 _DBUS_ASSERT_ERROR_IS_CLEAR (error);
94 to_read =
sizeof (int) * n_ints_in_buf - bytes;
102 ((
char*)buf) + bytes,
105 if (chunk < 0 && errno == EINTR)
112 "Failed to read from child pipe (%s)",
113 _dbus_strerror (errno));
127 *n_ints_read = (int)(bytes /
sizeof(
int));
140 _DBUS_ASSERT_ERROR_IS_CLEAR (error);
149 to_read =
sizeof (pid_t) - bytes;
157 ((
char*)buf) + bytes,
159 if (chunk < 0 && errno == EINTR)
166 "Failed to read from child pipe (%s)",
167 _dbus_strerror (errno));
262 DBusBabysitterFinishedFunc finished_cb;
273 _dbus_babysitter_new (
void)
281 sitter->refcount = 1;
312 sitter->refcount += 1;
334 sitter->refcount -= 1;
335 if (sitter->refcount == 0)
344 close_socket_to_babysitter (sitter);
346 close_error_pipe_from_child (sitter);
357 ret = waitpid (sitter->
sitter_pid, &status, WNOHANG);
369 ret = waitpid (sitter->
sitter_pid, &status, 0);
371 while (_DBUS_UNLIKELY (ret < 0 && errno == EINTR));
377 _dbus_warn (
"Babysitter process not available to be reaped; should not happen");
379 _dbus_warn (
"Unexpected error %d in waitpid() for babysitter: %s",
380 errno, _dbus_strerror (errno));
384 _dbus_verbose (
"Reaped %ld, waiting for babysitter %ld\n",
387 if (WIFEXITED (sitter->
status))
388 _dbus_verbose (
"Babysitter exited with status %d\n",
389 WEXITSTATUS (sitter->
status));
390 else if (WIFSIGNALED (sitter->
status))
391 _dbus_verbose (
"Babysitter received signal %d\n",
392 WTERMSIG (sitter->
status));
394 _dbus_verbose (
"Babysitter exited abnormally\n");
418 r = read_ints (fd, &what, 1, &got, &error);
443 case CHILD_FORK_FAILED:
444 case CHILD_EXEC_FAILED:
448 r = read_ints (fd, &arg, 1, &got, &error);
467 if (what == CHILD_EXITED)
486 sitter->have_child_status =
TRUE;
488 _dbus_verbose (
"recorded child status exited = %d signaled = %d exitstatus = %d termsig = %d\n",
489 WIFEXITED (sitter->
status), WIFSIGNALED (sitter->
status),
490 WEXITSTATUS (sitter->
status), WTERMSIG (sitter->
status));
492 else if (what == CHILD_FORK_FAILED)
496 _dbus_verbose (
"recorded fork errnum %d\n", sitter->
errnum);
498 else if (what == CHILD_EXEC_FAILED)
502 _dbus_verbose (
"recorded exec errnum %d\n", sitter->
errnum);
511 r = read_pid (fd, &pid, &error);
530 _dbus_verbose (
"recorded grandchild pid %d\n", sitter->
grandchild_pid);
534 _dbus_warn (
"Unknown message received from babysitter process");
545 _dbus_verbose (
"Closing babysitter\n");
566 _dbus_verbose (
"Closing child error\n");
594 _dbus_verbose (
"Reading data from babysitter\n");
596 close_socket_to_babysitter (sitter);
600 close_socket_to_babysitter (sitter);
610 _dbus_verbose (
"Reading data from child error\n");
612 close_error_pipe_from_child (sitter);
616 close_error_pipe_from_child (sitter);
629 descriptors_ready =
FALSE;
657 while (ret < 0 && errno == EINTR);
659 if (ret == 0 && block)
665 while (ret < 0 && errno == EINTR);
670 descriptors_ready =
TRUE;
676 handle_error_pipe (sitter, fds[i].revents);
678 handle_babysitter_socket (sitter, fds[i].revents);
683 return descriptors_ready;
690 #define LIVE_CHILDREN(sitter) ((sitter)->socket_to_babysitter.fd >= 0 || (sitter)->error_pipe_from_child >= 0) 704 babysitter_iteration (sitter,
TRUE);
706 _dbus_verbose (
"Got child PID %ld for killing\n",
726 babysitter_iteration (sitter,
FALSE))
752 if (!sitter->have_child_status ||
753 !(WIFEXITED (sitter->
status)))
756 *status = WEXITSTATUS (sitter->
status);
783 "Failed to execute program %s: %s",
789 "Failed to fork a new process %s: %s",
792 else if (sitter->have_child_status)
794 if (WIFEXITED (sitter->
status))
796 "Process %s exited with status %d",
798 else if (WIFSIGNALED (sitter->
status))
800 "Process %s received signal %d",
804 "Process %s exited abnormally",
810 "Process %s exited, reason unknown",
845 unsigned int condition,
863 handle_error_pipe (sitter, revents);
865 handle_babysitter_socket (sitter, revents);
868 babysitter_iteration (sitter,
FALSE))
877 sitter->finished_cb !=
NULL)
879 sitter->finished_cb (sitter, sitter->finished_data);
880 sitter->finished_cb =
NULL;
903 close_and_invalidate (
int *fd)
927 retval = pipe2 (p, O_CLOEXEC);
928 cloexec_done = retval >= 0;
932 if (retval < 0 && errno == ENOSYS)
938 _DBUS_ASSERT_ERROR_IS_CLEAR (error);
944 "Failed to create pipe for communicating with child process (%s)",
945 _dbus_strerror (errno));
961 do_write (
int fd,
const void *buf,
size_t count)
963 size_t bytes_written;
970 ret = write (fd, ((
const char*)buf) + bytes_written, count - bytes_written);
983 bytes_written += ret;
985 if (bytes_written < count)
989 static void write_err_and_exit (
int fd,
int msg) _DBUS_GNUC_NORETURN;
992 write_err_and_exit (
int fd,
int msg)
996 do_write (fd, &msg,
sizeof (msg));
997 do_write (fd, &en,
sizeof (en));
1003 write_pid (
int fd, pid_t pid)
1005 int msg = CHILD_PID;
1007 do_write (fd, &msg,
sizeof (msg));
1008 do_write (fd, &pid,
sizeof (pid));
1011 static void write_status_and_exit (
int fd,
int status) _DBUS_GNUC_NORETURN;
1014 write_status_and_exit (
int fd,
int status)
1016 int msg = CHILD_EXITED;
1018 do_write (fd, &msg,
sizeof (msg));
1019 do_write (fd, &status,
sizeof (status));
1024 static void do_exec (
int child_err_report_fd,
1027 DBusSpawnChildSetupFunc child_setup,
1028 void *user_data) _DBUS_GNUC_NORETURN;
1031 do_exec (
int child_err_report_fd,
1034 DBusSpawnChildSetupFunc child_setup,
1037 #ifdef DBUS_ENABLE_EMBEDDED_TESTS 1041 _dbus_verbose_reset ();
1046 (* child_setup) (user_data);
1048 #ifdef DBUS_ENABLE_EMBEDDED_TESTS 1049 max_open = sysconf (_SC_OPEN_MAX);
1051 for (i = 3; i < max_open; i++)
1055 if (i == child_err_report_fd)
1058 retval = fcntl (i, F_GETFD);
1060 if (retval != -1 && !(retval & FD_CLOEXEC))
1061 _dbus_warn (
"Fd %d did not have the close-on-exec flag set!", i);
1072 execve (argv[0], argv, envp);
1075 write_err_and_exit (child_err_report_fd,
1094 while (ret < 0 && errno == EINTR);
1098 _dbus_verbose (
"no child exited\n");
1105 _dbus_warn (
"unexpected waitpid() failure in check_babysit_events(): %s",
1106 _dbus_strerror (errno));
1112 _dbus_verbose (
"reaped child pid %ld\n", (
long) ret);
1114 write_status_and_exit (parent_pipe, status);
1118 _dbus_warn (
"waitpid() reaped pid %d that we've never heard of",
1125 _dbus_verbose (
"babysitter got POLLIN from parent pipe\n");
1131 _dbus_verbose (
"babysitter got POLLERR or POLLHUP from parent\n");
1136 static int babysit_sigchld_pipe = -1;
1139 babysit_signal_handler (
int signo)
1143 if (write (babysit_sigchld_pipe, &b, 1) <= 0)
1149 int parent_pipe) _DBUS_GNUC_NORETURN;
1155 int sigchld_pipe[2];
1160 _dbus_verbose_reset ();
1167 if (pipe (sigchld_pipe) < 0)
1169 _dbus_warn (
"Not enough file descriptors to create pipe in babysitter process");
1173 babysit_sigchld_pipe = sigchld_pipe[
WRITE_END];
1185 pfds[0].
fd = parent_pipe;
1195 _dbus_warn (
"_dbus_poll() error: %s", strerror (errno));
1199 if (pfds[0].revents != 0)
1201 check_babysit_events (
grandchild_pid, parent_pipe, pfds[0].revents);
1206 if (read (sigchld_pipe[
READ_END], &b, 1) == -1)
1247 DBusSpawnFlags flags,
1248 DBusSpawnChildSetupFunc child_setup,
1253 int child_err_report_pipe[2] = { -1, -1 };
1254 DBusSocket babysitter_pipe[2] = { DBUS_SOCKET_INIT, DBUS_SOCKET_INIT };
1261 _DBUS_ASSERT_ERROR_IS_CLEAR (error);
1264 if (sitter_p !=
NULL)
1269 sitter = _dbus_babysitter_new ();
1280 goto cleanup_and_fail;
1289 goto cleanup_and_fail;
1292 if (!make_pipe (child_err_report_pipe, error))
1293 goto cleanup_and_fail;
1296 goto cleanup_and_fail;
1309 goto cleanup_and_fail;
1321 goto cleanup_and_fail;
1330 goto cleanup_and_fail;
1342 goto cleanup_and_fail;
1345 _DBUS_ASSERT_ERROR_IS_CLEAR (error);
1348 if (flags & DBUS_SPAWN_REDIRECT_OUTPUT)
1354 fd_out = sd_journal_stream_fd (sitter->
log_name, LOG_INFO,
FALSE);
1355 fd_err = sd_journal_stream_fd (sitter->
log_name, LOG_WARNING,
FALSE);
1365 "Failed to fork (%s)",
1366 _dbus_strerror (errno));
1367 goto cleanup_and_fail;
1377 signal (SIGPIPE, SIG_DFL);
1380 close_and_invalidate (&child_err_report_pipe[READ_END]);
1381 close_and_invalidate (&babysitter_pipe[0].fd);
1384 grandchild_pid = fork ();
1386 if (grandchild_pid < 0)
1388 write_err_and_exit (babysitter_pipe[1].fd,
1392 else if (grandchild_pid == 0)
1398 fd = open (
"/proc/self/oom_score_adj", O_WRONLY | O_CLOEXEC);
1403 fd = open (
"/proc/self/oom_score_adj", O_WRONLY);
1409 if (write (fd,
"0",
sizeof (
char)) < 0)
1410 _dbus_warn (
"writing oom_score_adj error: %s", strerror (errno));
1416 signal (SIGPIPE, SIG_IGN);
1418 close_and_invalidate (&babysitter_pipe[1].fd);
1422 dup2 (fd_out, STDOUT_FILENO);
1424 dup2 (fd_err, STDERR_FILENO);
1425 close_and_invalidate (&fd_out);
1426 close_and_invalidate (&fd_err);
1428 do_exec (child_err_report_pipe[
WRITE_END],
1431 child_setup, user_data);
1436 close_and_invalidate (&child_err_report_pipe[
WRITE_END]);
1438 close_and_invalidate (&fd_out);
1439 close_and_invalidate (&fd_err);
1441 babysit (grandchild_pid, babysitter_pipe[1].fd);
1448 close_and_invalidate (&child_err_report_pipe[
WRITE_END]);
1449 close_and_invalidate (&babysitter_pipe[1].fd);
1451 close_and_invalidate (&fd_out);
1452 close_and_invalidate (&fd_err);
1456 babysitter_pipe[0].fd = -1;
1459 child_err_report_pipe[
READ_END] = -1;
1463 if (sitter_p !=
NULL)
1470 _DBUS_ASSERT_ERROR_IS_CLEAR (error);
1477 _DBUS_ASSERT_ERROR_IS_SET (error);
1479 close_and_invalidate (&child_err_report_pipe[READ_END]);
1480 close_and_invalidate (&child_err_report_pipe[
WRITE_END]);
1481 close_and_invalidate (&babysitter_pipe[0].fd);
1482 close_and_invalidate (&babysitter_pipe[1].fd);
1484 close_and_invalidate (&fd_out);
1485 close_and_invalidate (&fd_err);
1496 DBusBabysitterFinishedFunc finished,
1499 sitter->finished_cb = finished;
1500 sitter->finished_data = user_data;
1509 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.
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.
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.
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_set_signal_handler(int sig, DBusSignalHandler handler)
Installs a UNIX signal handler.
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.