29#if defined(DBUS_WIN) || !defined(DBUS_UNIX)
30#error "This file only makes sense on Unix OSs"
33#include "dbus-spawn.h"
34#include "dbus-sysdeps-unix.h"
35#include "dbus-internals.h"
37#include "dbus-protocol.h"
52#include <systemd/sd-journal.h>
56# include <crt_externs.h>
57# define environ (*_NSGetEnviron ())
58#elif !HAVE_DECL_ENVIRON
92 _DBUS_ASSERT_ERROR_IS_CLEAR (error);
101 to_read =
sizeof (int) * n_ints_in_buf - bytes;
109 ((
char*)buf) + bytes,
112 if (chunk < 0 && errno == EINTR)
119 "Failed to read from child pipe (%s)",
120 _dbus_strerror (errno));
134 *n_ints_read = (int)(bytes /
sizeof(
int));
147 _DBUS_ASSERT_ERROR_IS_CLEAR (error);
156 to_read =
sizeof (pid_t) - bytes;
164 ((
char*)buf) + bytes,
166 if (chunk < 0 && errno == EINTR)
173 "Failed to read from child pipe (%s)",
174 _dbus_strerror (errno));
269 DBusBabysitterFinishedFunc finished_cb;
280_dbus_babysitter_new (
void)
351 close_socket_to_babysitter (sitter);
353 close_error_pipe_from_child (sitter);
364 ret = waitpid (sitter->
sitter_pid, &status, WNOHANG);
376 ret = waitpid (sitter->
sitter_pid, &status, 0);
378 while (_DBUS_UNLIKELY (ret < 0 && errno == EINTR));
384 _dbus_warn (
"Babysitter process not available to be reaped; should not happen");
386 _dbus_warn (
"Unexpected error %d in waitpid() for babysitter: %s",
387 errno, _dbus_strerror (errno));
391 _dbus_verbose (
"Reaped %ld, waiting for babysitter %ld\n",
394 if (WIFEXITED (sitter->
status))
395 _dbus_verbose (
"Babysitter exited with status %d\n",
396 WEXITSTATUS (sitter->
status));
397 else if (WIFSIGNALED (sitter->
status))
398 _dbus_verbose (
"Babysitter received signal %d\n",
399 WTERMSIG (sitter->
status));
401 _dbus_verbose (
"Babysitter exited abnormally\n");
425 r = read_ints (fd, &what, 1, &got, &error);
450 case CHILD_FORK_FAILED:
451 case CHILD_EXEC_FAILED:
455 r = read_ints (fd, &arg, 1, &got, &error);
474 if (what == CHILD_EXITED)
495 _dbus_verbose (
"recorded child status exited = %d signaled = %d exitstatus = %d termsig = %d\n",
496 WIFEXITED (sitter->
status), WIFSIGNALED (sitter->
status),
497 WEXITSTATUS (sitter->
status), WTERMSIG (sitter->
status));
499 else if (what == CHILD_FORK_FAILED)
503 _dbus_verbose (
"recorded fork errnum %d\n", sitter->
errnum);
505 else if (what == CHILD_EXEC_FAILED)
509 _dbus_verbose (
"recorded exec errnum %d\n", sitter->
errnum);
518 r = read_pid (fd, &pid, &error);
537 _dbus_verbose (
"recorded grandchild pid %d\n", sitter->
grandchild_pid);
541 _dbus_warn (
"Unknown message received from babysitter process");
552 _dbus_verbose (
"Closing babysitter\n");
573 _dbus_verbose (
"Closing child error\n");
601 _dbus_verbose (
"Reading data from babysitter\n");
603 close_socket_to_babysitter (sitter);
607 close_socket_to_babysitter (sitter);
617 _dbus_verbose (
"Reading data from child error\n");
619 close_error_pipe_from_child (sitter);
623 close_error_pipe_from_child (sitter);
636 descriptors_ready =
FALSE;
664 while (ret < 0 && errno == EINTR);
666 if (ret == 0 && block)
672 while (ret < 0 && errno == EINTR);
677 descriptors_ready =
TRUE;
683 handle_error_pipe (sitter, fds[i].revents);
685 handle_babysitter_socket (sitter, fds[i].revents);
690 return descriptors_ready;
697#define LIVE_CHILDREN(sitter) ((sitter)->socket_to_babysitter.fd >= 0 || (sitter)->error_pipe_from_child >= 0)
711 babysitter_iteration (sitter,
TRUE);
713 _dbus_verbose (
"Got child PID %ld for killing\n",
733 babysitter_iteration (sitter,
FALSE))
760 !(WIFEXITED (sitter->
status)))
763 *status = WEXITSTATUS (sitter->
status);
790 "Failed to execute program %s: %s",
796 "Failed to fork a new process %s: %s",
801 if (WIFEXITED (sitter->
status))
803 "Process %s exited with status %d",
805 else if (WIFSIGNALED (sitter->
status))
807 "Process %s received signal %d",
811 "Process %s exited abnormally",
817 "Process %s exited, reason unknown",
852 unsigned int condition,
870 handle_error_pipe (sitter, revents);
872 handle_babysitter_socket (sitter, revents);
875 babysitter_iteration (sitter,
FALSE))
884 sitter->finished_cb !=
NULL)
886 sitter->finished_cb (sitter, sitter->finished_data);
887 sitter->finished_cb =
NULL;
910close_and_invalidate (
int *fd)
934 retval = pipe2 (p, O_CLOEXEC);
935 cloexec_done = retval >= 0;
939 if (retval < 0 && errno == ENOSYS)
945 _DBUS_ASSERT_ERROR_IS_CLEAR (error);
951 "Failed to create pipe for communicating with child process (%s)",
952 _dbus_strerror (errno));
968do_write (
int fd,
const void *buf,
size_t count)
970 size_t bytes_written;
977 ret = write (fd, ((
const char*)buf) + bytes_written, count - bytes_written);
990 bytes_written += ret;
992 if (bytes_written < count)
996static void write_err_and_exit (
int fd,
int msg) _DBUS_GNUC_NORETURN;
999write_err_and_exit (
int fd,
int msg)
1003 do_write (fd, &msg,
sizeof (msg));
1004 do_write (fd, &en,
sizeof (en));
1010write_pid (
int fd, pid_t pid)
1012 int msg = CHILD_PID;
1014 do_write (fd, &msg,
sizeof (msg));
1015 do_write (fd, &pid,
sizeof (pid));
1018static void write_status_and_exit (
int fd,
int status) _DBUS_GNUC_NORETURN;
1021write_status_and_exit (
int fd,
int status)
1023 int msg = CHILD_EXITED;
1025 do_write (fd, &msg,
sizeof (msg));
1026 do_write (fd, &status,
sizeof (status));
1031static void do_exec (
int child_err_report_fd,
1034 DBusSpawnChildSetupFunc child_setup,
1035 void *user_data) _DBUS_GNUC_NORETURN;
1038do_exec (
int child_err_report_fd,
1041 DBusSpawnChildSetupFunc child_setup,
1044#ifdef DBUS_ENABLE_EMBEDDED_TESTS
1048 _dbus_verbose_reset ();
1053 (* child_setup) (user_data);
1055#ifdef DBUS_ENABLE_EMBEDDED_TESTS
1056 max_open = sysconf (_SC_OPEN_MAX);
1058 for (i = 3; i < max_open; i++)
1062 if (i == child_err_report_fd)
1065 retval = fcntl (i, F_GETFD);
1067 if (retval != -1 && !(retval & FD_CLOEXEC))
1069 char description[256] = { 0 };
1070 char proc_self_fd[256] = { 0 };
1071 size_t description_length =
sizeof (description) - 1;
1073 snprintf (proc_self_fd,
sizeof (proc_self_fd) - 1,
1074 "/proc/self/fd/%d", i);
1075 proc_self_fd[
sizeof (proc_self_fd) - 1] =
'\0';
1077 if (readlink (proc_self_fd, description, description_length) <= 0)
1078 snprintf (description,
sizeof (description) - 1,
"(unknown)");
1080 description[
sizeof (description) - 1] =
'\0';
1081 _dbus_warn (
"Fd %d \"%s\" did not have the close-on-exec flag set!",
1094 execve (argv[0], argv, envp);
1097 write_err_and_exit (child_err_report_fd,
1102check_babysit_events (pid_t grandchild_pid,
1111 ret = waitpid (grandchild_pid, &status, WNOHANG);
1116 while (ret < 0 && errno == EINTR);
1120 _dbus_verbose (
"no child exited\n");
1127 _dbus_warn (
"unexpected waitpid() failure in check_babysit_events(): %s",
1128 _dbus_strerror (errno));
1131 else if (ret == grandchild_pid)
1134 _dbus_verbose (
"reaped child pid %ld\n", (
long) ret);
1136 write_status_and_exit (parent_pipe, status);
1140 _dbus_warn (
"waitpid() reaped pid %d that we've never heard of",
1147 _dbus_verbose (
"babysitter got POLLIN from parent pipe\n");
1153 _dbus_verbose (
"babysitter got POLLERR or POLLHUP from parent\n");
1160static int babysit_sigchld_pipe = -1;
1163babysit_signal_handler (
int signo)
1167 int saved_errno = errno;
1171 if (write (babysit_sigchld_pipe, &b, 1) <= 0)
1175 errno = saved_errno;
1178static void babysit (pid_t grandchild_pid,
1179 int parent_pipe) _DBUS_GNUC_NORETURN;
1182babysit (pid_t grandchild_pid,
1185 int sigchld_pipe[2];
1190 _dbus_verbose_reset ();
1197 if (pipe (sigchld_pipe) < 0)
1199 _dbus_warn (
"Not enough file descriptors to create pipe in babysitter process");
1203 babysit_sigchld_pipe = sigchld_pipe[
WRITE_END];
1207 write_pid (parent_pipe, grandchild_pid);
1209 check_babysit_events (grandchild_pid, parent_pipe, 0);
1215 pfds[0].
fd = parent_pipe;
1225 _dbus_warn (
"_dbus_poll() error: %s", strerror (errno));
1229 if (pfds[0].revents != 0)
1231 check_babysit_events (grandchild_pid, parent_pipe, pfds[0].revents);
1236 if (read (sigchld_pipe[
READ_END], &b, 1) == -1)
1241 check_babysit_events (grandchild_pid, parent_pipe, 0);
1274 const char *log_name,
1277 DBusSpawnFlags flags,
1278 DBusSpawnChildSetupFunc child_setup,
1283 int child_err_report_pipe[2] = { -1, -1 };
1284 DBusSocket babysitter_pipe[2] = { DBUS_SOCKET_INIT, DBUS_SOCKET_INIT };
1289 _DBUS_ASSERT_ERROR_IS_CLEAR (error);
1292 if (sitter_p !=
NULL)
1297 sitter = _dbus_babysitter_new ();
1308 goto cleanup_and_fail;
1317 goto cleanup_and_fail;
1320 if (!make_pipe (child_err_report_pipe, error))
1321 goto cleanup_and_fail;
1324 goto cleanup_and_fail;
1337 goto cleanup_and_fail;
1349 goto cleanup_and_fail;
1358 goto cleanup_and_fail;
1370 goto cleanup_and_fail;
1373 _DBUS_ASSERT_ERROR_IS_CLEAR (error);
1375 if (flags & DBUS_SPAWN_SILENCE_OUTPUT)
1377 fd_out = open (
"/dev/null", O_RDONLY);
1382 "Failed to open /dev/null: %s",
1383 _dbus_strerror (errno));
1384 goto cleanup_and_fail;
1392 goto cleanup_and_fail;
1395 else if (flags & DBUS_SPAWN_REDIRECT_OUTPUT)
1401 fd_out = sd_journal_stream_fd (sitter->
log_name, LOG_INFO,
FALSE);
1402 fd_err = sd_journal_stream_fd (sitter->
log_name, LOG_WARNING,
FALSE);
1417 "Failed to fork (%s)",
1418 _dbus_strerror (errno));
1419 goto cleanup_and_fail;
1429 signal (SIGPIPE, SIG_DFL);
1432 close_and_invalidate (&child_err_report_pipe[
READ_END]);
1433 close_and_invalidate (&babysitter_pipe[0].fd);
1439 grandchild_pid = fork ();
1441 if (grandchild_pid < 0)
1443 write_err_and_exit (babysitter_pipe[1].fd,
1447 else if (grandchild_pid == 0)
1457 signal (SIGPIPE, SIG_IGN);
1459 close_and_invalidate (&babysitter_pipe[1].fd);
1464 dup2 (fd_out, STDOUT_FILENO);
1466 dup2 (fd_err, STDERR_FILENO);
1467 close_and_invalidate (&fd_out);
1468 close_and_invalidate (&fd_err);
1470 do_exec (child_err_report_pipe[
WRITE_END],
1473 child_setup, user_data);
1478 close_and_invalidate (&child_err_report_pipe[
WRITE_END]);
1479 close_and_invalidate (&fd_out);
1480 close_and_invalidate (&fd_err);
1481 babysit (grandchild_pid, babysitter_pipe[1].fd);
1488 close_and_invalidate (&child_err_report_pipe[
WRITE_END]);
1489 close_and_invalidate (&babysitter_pipe[1].fd);
1490 close_and_invalidate (&fd_out);
1491 close_and_invalidate (&fd_err);
1494 babysitter_pipe[0].fd = -1;
1497 child_err_report_pipe[
READ_END] = -1;
1501 if (sitter_p !=
NULL)
1506 _DBUS_ASSERT_ERROR_IS_CLEAR (error);
1513 _DBUS_ASSERT_ERROR_IS_SET (error);
1515 close_and_invalidate (&child_err_report_pipe[
READ_END]);
1516 close_and_invalidate (&child_err_report_pipe[
WRITE_END]);
1517 close_and_invalidate (&babysitter_pipe[0].fd);
1518 close_and_invalidate (&babysitter_pipe[1].fd);
1519 close_and_invalidate (&fd_out);
1520 close_and_invalidate (&fd_err);
1530 DBusBabysitterFinishedFunc finished,
1533 sitter->finished_cb = finished;
1534 sitter->finished_data = user_data;
1543 babysitter_iteration (sitter,
TRUE);
void(* DBusWatchToggledFunction)(DBusWatch *watch, void *data)
Called when dbus_watch_get_enabled() may return a different value than it did before.
dbus_bool_t(* DBusAddWatchFunction)(DBusWatch *watch, void *data)
Called when libdbus needs a new watch to be monitored by the main loop.
void(* DBusRemoveWatchFunction)(DBusWatch *watch, void *data)
Called when libdbus no longer needs a watch to be monitored by the main loop.
@ DBUS_WATCH_READABLE
As in POLLIN.
@ DBUS_WATCH_HANGUP
As in POLLHUP (can't watch for it, but can be present in current state passed to dbus_watch_handle())...
@ DBUS_WATCH_ERROR
As in POLLERR (can't watch for this, but can be present in current state passed to dbus_watch_handle(...
#define DBUS_ERROR_INIT
Expands to a suitable initializer for a DBusError on the stack.
void dbus_set_error(DBusError *error, const char *name, const char *format,...)
Assigns an error name and message to a DBusError.
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...
#define _dbus_assert_not_reached(explanation)
Aborts with an error message if called.
#define _dbus_assert(condition)
Aborts with an error message if the condition is false.
dbus_bool_t _dbus_babysitter_get_child_exit_status(DBusBabysitter *sitter, int *status)
Gets the exit status of the child.
#define READ_END
Helps remember which end of the pipe is which.
#define WRITE_END
Helps remember which end of the pipe is which.
void _dbus_babysitter_unref(DBusBabysitter *sitter)
Decrement the reference count on the babysitter object.
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_babysitter_get_child_exited(DBusBabysitter *sitter)
Checks whether the child has exited, without blocking.
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.
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,...
ReadStatus
Enumeration for status of a read()
void _dbus_warn(const char *format,...)
Prints a warning message to stderr.
#define _DBUS_N_ELEMENTS(array)
Computes the number of elements in a fixed-size array using sizeof().
void _dbus_babysitter_kill_child(DBusBabysitter *sitter)
Blocks until the babysitter process gives us the PID of the spawned grandchild, then kills the spawne...
DBusBabysitter * _dbus_babysitter_ref(DBusBabysitter *sitter)
Increment the reference count on the babysitter object.
dbus_bool_t _dbus_spawn_async_with_babysitter(DBusBabysitter **sitter_p, const char *log_name, char *const *argv, char *const *env, DBusSpawnFlags flags, DBusSpawnChildSetupFunc child_setup, void *user_data, DBusError *error)
Spawns a new process.
#define LIVE_CHILDREN(sitter)
Macro returns TRUE if the babysitter still has live sockets open to the babysitter child or the grand...
@ READ_STATUS_OK
Read succeeded.
@ READ_STATUS_EOF
EOF returned.
@ READ_STATUS_ERROR
Some kind of error.
#define NULL
A null pointer, defined appropriately for C or C++.
#define TRUE
Expands to "1".
#define FALSE
Expands to "0".
void(* DBusFreeFunction)(void *memory)
The type of a function which frees a block of memory.
void dbus_free(void *memory)
Frees a block of memory previously allocated by dbus_malloc() or dbus_malloc0().
#define dbus_new0(type, count)
Safe macro for using dbus_malloc0().
#define DBUS_ERROR_SPAWN_CHILD_EXITED
While starting a new process, the child exited with a status code.
#define DBUS_ERROR_SPAWN_CHILD_SIGNALED
While starting a new process, the child exited on a signal.
#define DBUS_ERROR_FAILED
A generic error; "something went wrong" - see the error message for more.
#define DBUS_ERROR_SPAWN_EXEC_FAILED
While starting a new process, the exec() call failed.
#define DBUS_ERROR_NO_MEMORY
There was not enough memory to complete an operation.
#define DBUS_ERROR_SPAWN_FAILED
While starting a new process, something went wrong.
#define DBUS_ERROR_SPAWN_FORK_FAILED
While starting a new process, the fork() call failed.
dbus_bool_t _dbus_reset_oom_score_adj(const char **error_str_p)
If the current process has been protected from the Linux OOM killer (the oom_score_adj process parame...
dbus_bool_t _dbus_close(int fd, DBusError *error)
Closes a file descriptor.
void _dbus_set_signal_handler(int sig, DBusSignalHandler handler)
Installs a UNIX signal handler.
int _dbus_dup(int fd, DBusError *error)
Duplicates a file descriptor.
void _dbus_fd_set_close_on_exec(int fd)
Sets the file descriptor to be close on exec.
#define _DBUS_POLLERR
Error condition.
dbus_bool_t _dbus_socketpair(DBusSocket *fd1, DBusSocket *fd2, dbus_bool_t blocking, DBusError *error)
Creates pair of connect sockets (as in socketpair()).
dbus_pid_t _dbus_getpid(void)
Gets our process ID.
#define _DBUS_POLLHUP
Hung up.
#define _DBUS_POLLIN
There is data to read.
dbus_bool_t _dbus_close_socket(DBusSocket *fd, DBusError *error)
Closes a socket and invalidates it.
int _dbus_poll(DBusPollFD *fds, int n_fds, int timeout_milliseconds)
Wrapper for poll().
#define DBUS_PID_FORMAT
an appropriate printf format for dbus_pid_t
dbus_uint32_t dbus_bool_t
A boolean, valid values are TRUE and FALSE.
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.
DBusWatchList * _dbus_watch_list_new(void)
Creates a new watch list.
void _dbus_watch_list_free(DBusWatchList *watch_list)
Frees a DBusWatchList.
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.
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.
void _dbus_watch_unref(DBusWatch *watch)
Decrements the reference count of a DBusWatch object and finalizes the object if the count reaches ze...
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_watch_invalidate(DBusWatch *watch)
Clears the file descriptor from a now-invalid watch object so that no one tries to use it.
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...
Babysitter implementation details.
DBusWatch * sitter_watch
Sitter pipe watch.
unsigned int have_exec_errnum
True if we have an error code from exec()
DBusSocket socket_to_babysitter
Connection to the babysitter process.
int status
Exit status code.
unsigned int have_child_status
True if child status has been reaped.
char * log_name
the name under which to log messages about this process being spawned
pid_t sitter_pid
PID Of the babysitter.
int error_pipe_from_child
Connection to the process that does the exec()
int refcount
Reference count.
DBusWatchList * watches
Watches.
DBusWatch * error_watch
Error pipe watch.
pid_t grandchild_pid
PID of the grandchild.
unsigned int have_fork_errnum
True if we have an error code from fork()
Object representing an exception.
const char * message
public error message field
short events
Events to poll for.
short revents
Events that occurred.
DBusPollable fd
File descriptor.
DBusWatchList implementation details.
Implementation of DBusWatch.