static void
free_watches (DBusTransport *transport)
{
DBusTransportSocket *socket_transport = (DBusTransportSocket*) transport;
_dbus_verbose ("start\n");
if (socket_transport->read_watch)
{
if (transport->connection)
_dbus_connection_remove_watch_unlocked (transport->connection,
socket_transport->read_watch);
_dbus_watch_invalidate (socket_transport->read_watch);
_dbus_watch_unref (socket_transport->read_watch);
socket_transport->read_watch = NULL;
}
if (socket_transport->write_watch)
{
if (transport->connection)
_dbus_connection_remove_watch_unlocked (transport->connection,
socket_transport->write_watch);
_dbus_watch_invalidate (socket_transport->write_watch);
_dbus_watch_unref (socket_transport->write_watch);
socket_transport->write_watch = NULL;
}
_dbus_verbose ("end\n");
}
static dbus_bool_t
handle_watch (DBusWatch *watch,
unsigned int condition,
void *data)
{
DBusBabysitter *sitter = data;
int revents;
int fd;
revents = 0;
if (condition & DBUS_WATCH_READABLE)
revents |= _DBUS_POLLIN;
if (condition & DBUS_WATCH_ERROR)
revents |= _DBUS_POLLERR;
if (condition & DBUS_WATCH_HANGUP)
revents |= _DBUS_POLLHUP;
fd = dbus_watch_get_socket (watch);
if (fd == sitter->error_pipe_from_child)
handle_error_pipe (sitter, revents);
else if (fd == sitter->socket_to_babysitter)
handle_babysitter_socket (sitter, revents);
while (LIVE_CHILDREN (sitter) &&
babysitter_iteration (sitter, FALSE))
;
/* Those might have closed the sockets we're watching. Before returning
* to the main loop, we must sort that out. */
if (sitter->error_watch != NULL && sitter->error_pipe_from_child == -1)
{
_dbus_watch_invalidate (sitter->error_watch);
if (sitter->watches != NULL)
_dbus_watch_list_remove_watch (sitter->watches, sitter->error_watch);
_dbus_watch_unref (sitter->error_watch);
sitter->error_watch = NULL;
}
if (sitter->sitter_watch != NULL && sitter->socket_to_babysitter == -1)
{
_dbus_watch_invalidate (sitter->sitter_watch);
if (sitter->watches != NULL)
_dbus_watch_list_remove_watch (sitter->watches, sitter->sitter_watch);
_dbus_watch_unref (sitter->sitter_watch);
sitter->sitter_watch = NULL;
}
return TRUE;
}
/**
* Adds a new watch to the watch list, invoking the
* application DBusAddWatchFunction if appropriate.
*
* @param watch_list the watch list.
* @param watch the watch to add.
* @returns #TRUE on success, #FALSE if no memory.
*/
dbus_bool_t
_dbus_watch_list_add_watch (DBusWatchList *watch_list,
DBusWatch *watch)
{
if (!_dbus_list_append (&watch_list->watches, watch))
return FALSE;
_dbus_watch_ref (watch);
if (watch_list->add_watch_function != NULL)
{
_dbus_verbose ("Adding watch on fd %d\n",
dbus_watch_get_socket (watch));
if (!(* watch_list->add_watch_function) (watch,
watch_list->watch_data))
{
_dbus_list_remove_last (&watch_list->watches, watch);
_dbus_watch_unref (watch);
return FALSE;
}
}
return TRUE;
}
static void
socket_disconnect (DBusServer *server)
{
DBusServerSocket *socket_server = (DBusServerSocket*) server;
int i;
HAVE_LOCK_CHECK (server);
for (i = 0 ; i < socket_server->n_fds ; i++)
{
if (socket_server->watch[i])
{
_dbus_server_remove_watch (server,
socket_server->watch[i]);
_dbus_watch_unref (socket_server->watch[i]);
socket_server->watch[i] = NULL;
}
_dbus_close_socket (socket_server->fds[i], NULL);
socket_server->fds[i] = -1;
}
if (socket_server->socket_name != NULL)
{
DBusString tmp;
_dbus_string_init_const (&tmp, socket_server->socket_name);
_dbus_delete_file (&tmp, NULL);
}
if (server->published_address)
_dbus_daemon_unpublish_session_bus_address();
HAVE_LOCK_CHECK (server);
}
/**
* Adds a new watch to the watch list, invoking the
* application DBusAddWatchFunction if appropriate.
*
* @param watch_list the watch list.
* @param watch the watch to add.
* @returns #TRUE on success, #FALSE if no memory.
*/
dbus_bool_t
_dbus_watch_list_add_watch (DBusWatchList *watch_list,
DBusWatch *watch)
{
if (!_dbus_list_append (&watch_list->watches, watch))
return FALSE;
_dbus_watch_ref (watch);
if (watch_list->add_watch_function != NULL)
{
_dbus_verbose ("Adding watch on fd %" DBUS_POLLABLE_FORMAT "\n",
_dbus_pollable_printable (watch->fd));
if (!(* watch_list->add_watch_function) (watch,
watch_list->watch_data))
{
_dbus_list_remove_last (&watch_list->watches, watch);
_dbus_watch_unref (watch);
return FALSE;
}
}
return TRUE;
}
/**
* Handles a watch by reading data, writing data, or disconnecting
* the transport, as appropriate for the given condition.
*
* @param transport the transport.
* @param watch the watch.
* @param condition the current state of the watched file descriptor.
* @returns #FALSE if not enough memory to fully handle the watch
*/
dbus_bool_t
_dbus_transport_handle_watch (DBusTransport *transport,
DBusWatch *watch,
unsigned int condition)
{
dbus_bool_t retval;
_dbus_assert (transport->vtable->handle_watch != NULL);
if (transport->disconnected)
return TRUE;
if (dbus_watch_get_socket (watch) < 0)
{
_dbus_warn_check_failed ("Tried to handle an invalidated watch; this watch should have been removed\n");
return TRUE;
}
_dbus_watch_sanitize_condition (watch, &condition);
_dbus_transport_ref (transport);
_dbus_watch_ref (watch);
retval = (* transport->vtable->handle_watch) (transport, watch, condition);
_dbus_watch_unref (watch);
_dbus_transport_unref (transport);
return retval;
}
static void
close_reload_pipe (DBusWatch **watch)
{
_dbus_loop_remove_watch (bus_context_get_loop (context), *watch);
_dbus_watch_invalidate (*watch);
_dbus_watch_unref (*watch);
*watch = NULL;
_dbus_close_socket (reload_pipe[RELOAD_READ_END], NULL);
reload_pipe[RELOAD_READ_END] = -1;
_dbus_close_socket (reload_pipe[RELOAD_WRITE_END], NULL);
reload_pipe[RELOAD_WRITE_END] = -1;
}
static int
_init_kqueue (BusContext *context)
{
int ret = 0;
if (kq < 0)
{
kq = kqueue ();
if (kq < 0)
{
_dbus_warn ("Cannot create kqueue; error '%s'\n", _dbus_strerror (errno));
goto out;
}
loop = bus_context_get_loop (context);
watch = _dbus_watch_new (kq, DBUS_WATCH_READABLE, TRUE,
_handle_kqueue_watch, NULL, NULL);
if (watch == NULL)
{
_dbus_warn ("Unable to create kqueue watch\n");
close (kq);
kq = -1;
goto out;
}
if (!_dbus_loop_add_watch (loop, watch))
{
_dbus_warn ("Unable to add reload watch to main loop");
_dbus_watch_invalidate (watch);
_dbus_watch_unref (watch);
watch = NULL;
close (kq);
kq = -1;
goto out;
}
}
ret = 1;
out:
return ret;
}
/**
* Removes a watch from the watch list, invoking the
* application's DBusRemoveWatchFunction if appropriate.
*
* @param watch_list the watch list.
* @param watch the watch to remove.
*/
void
_dbus_watch_list_remove_watch (DBusWatchList *watch_list,
DBusWatch *watch)
{
if (!_dbus_list_remove (&watch_list->watches, watch))
_dbus_assert_not_reached ("Nonexistent watch was removed");
if (watch_list->remove_watch_function != NULL)
{
_dbus_verbose ("Removing watch on fd %d\n",
dbus_watch_get_socket (watch));
(* watch_list->remove_watch_function) (watch,
watch_list->watch_data);
}
_dbus_watch_unref (watch);
}
/**
* Removes a watch from the watch list, invoking the
* application's DBusRemoveWatchFunction if appropriate.
*
* @param watch_list the watch list.
* @param watch the watch to remove.
*/
void
_dbus_watch_list_remove_watch (DBusWatchList *watch_list,
DBusWatch *watch)
{
if (!_dbus_list_remove (&watch_list->watches, watch))
_dbus_assert_not_reached ("Nonexistent watch was removed");
if (watch_list->remove_watch_function != NULL)
{
_dbus_verbose ("Removing watch on fd %" DBUS_POLLABLE_FORMAT "\n",
_dbus_pollable_printable (watch->fd));
(* watch_list->remove_watch_function) (watch,
watch_list->watch_data);
}
_dbus_watch_unref (watch);
}
static void
close_error_pipe_from_child (DBusBabysitter *sitter)
{
_dbus_verbose ("Closing child error\n");
if (sitter->error_watch != NULL)
{
_dbus_assert (sitter->watches != NULL);
_dbus_watch_list_remove_watch (sitter->watches, sitter->error_watch);
_dbus_watch_invalidate (sitter->error_watch);
_dbus_watch_unref (sitter->error_watch);
sitter->error_watch = NULL;
}
if (sitter->error_pipe_from_child >= 0)
{
_dbus_close (sitter->error_pipe_from_child, NULL);
sitter->error_pipe_from_child = -1;
}
}
static void
close_socket_to_babysitter (DBusBabysitter *sitter)
{
_dbus_verbose ("Closing babysitter\n");
if (sitter->sitter_watch != NULL)
{
_dbus_assert (sitter->watches != NULL);
_dbus_watch_list_remove_watch (sitter->watches, sitter->sitter_watch);
_dbus_watch_invalidate (sitter->sitter_watch);
_dbus_watch_unref (sitter->sitter_watch);
sitter->sitter_watch = NULL;
}
if (sitter->socket_to_babysitter.fd >= 0)
{
_dbus_close_socket (sitter->socket_to_babysitter, NULL);
sitter->socket_to_babysitter.fd = -1;
}
}
static void
free_watch_table_entry (void *data)
{
DBusList **watches = data;
DBusWatch *watch;
/* DBusHashTable sometimes calls free_function(NULL) even if you never
* have NULL as a value */
if (watches == NULL)
return;
for (watch = _dbus_list_pop_first (watches);
watch != NULL;
watch = _dbus_list_pop_first (watches))
{
_dbus_watch_unref (watch);
}
_dbus_assert (*watches == NULL);
dbus_free (watches);
}
static void _shutdown_kqueue (void *data)
{
int i;
if (kq < 0)
return;
for (i = 0; i < MAX_DIRS_TO_WATCH; i++)
{
if (fds[i] >= 0)
{
close (fds[i]);
fds[i] = -1;
}
if (dirs[i] != NULL)
{
/* dbus_free() is necessary to pass memleak check */
dbus_free (dirs[i]);
dirs[i] = NULL;
}
}
if (loop)
{
_dbus_loop_remove_watch (loop, watch);
_dbus_loop_unref (loop);
loop = NULL;
}
if (watch)
{
_dbus_watch_invalidate (watch);
_dbus_watch_unref (watch);
watch = NULL;
}
close (kq);
kq = -1;
}
static void
socket_finalize (DBusServer *server)
{
DBusServerSocket *socket_server = (DBusServerSocket*) server;
int i;
_dbus_server_finalize_base (server);
for (i = 0 ; i < socket_server->n_fds ; i++)
if (socket_server->watch[i])
{
_dbus_watch_unref (socket_server->watch[i]);
socket_server->watch[i] = NULL;
}
dbus_free (socket_server->fds);
dbus_free (socket_server->watch);
dbus_free (socket_server->socket_name);
if (socket_server->noncefile)
_dbus_noncefile_delete (socket_server->noncefile, NULL);
dbus_free (socket_server->noncefile);
dbus_free (server);
}
static dbus_bool_t
_handle_kqueue_watch (DBusWatch *watch, unsigned int flags, void *data)
{
struct kevent ev;
struct timespec nullts = { 0, 0 };
int res;
pid_t pid;
res = kevent (kq, NULL, 0, &ev, 1, &nullts);
/* Sleep for half a second to avoid a race when files are install(1)'d
* to system.d. */
usleep(500000);
if (res > 0)
{
pid = getpid ();
_dbus_verbose ("Sending SIGHUP signal on reception of a kevent\n");
(void) kill (pid, SIGHUP);
}
else if (res < 0 && errno == EBADF)
{
kq = -1;
if (watch != NULL)
{
_dbus_loop_remove_watch (loop, watch);
_dbus_watch_invalidate (watch);
_dbus_watch_unref (watch);
watch = NULL;
}
pid = getpid ();
_dbus_verbose ("Sending SIGHUP signal since kqueue has been closed\n");
(void) kill (pid, SIGHUP);
}
return TRUE;
}
static int
_init_kqueue (BusContext *context)
{
if (kq < 0)
{
kq = kqueue ();
if (kq < 0)
{
_dbus_warn ("Cannot create kqueue; error '%s'\n", _dbus_strerror (errno));
goto out;
}
loop = bus_context_get_loop (context);
_dbus_loop_ref (loop);
watch = _dbus_watch_new (kq, DBUS_WATCH_READABLE, TRUE,
_handle_kqueue_watch, NULL, NULL);
if (watch == NULL)
{
_dbus_warn ("Unable to create kqueue watch\n");
goto out1;
}
if (!_dbus_loop_add_watch (loop, watch))
{
_dbus_warn ("Unable to add reload watch to main loop");
goto out2;
}
if (!_dbus_register_shutdown_func (_shutdown_kqueue, NULL))
{
_dbus_warn ("Unable to register shutdown function");
goto out3;
}
}
return 1;
out3:
_dbus_loop_remove_watch (loop, watch);
out2:
if (watch)
{
_dbus_watch_invalidate (watch);
_dbus_watch_unref (watch);
watch = NULL;
}
out1:
if (kq >= 0)
{
close (kq);
kq = -1;
}
if (loop)
{
_dbus_loop_unref (loop);
loop = NULL;
}
out:
return 0;
}
/**
* Creates a new server listening on the given file descriptor. The
* file descriptor should be nonblocking (use
* _dbus_set_fd_nonblocking() to make it so). The file descriptor
* should be listening for connections, that is, listen() should have
* been successfully invoked on it. The server will use accept() to
* accept new client connections.
*
* @param fds list of file descriptors.
* @param n_fds number of file descriptors
* @param address the server's address
* @param noncefile to be used for authentication (NULL if not needed)
* @returns the new server, or #NULL if no memory.
*
*/
DBusServer*
_dbus_server_new_for_socket (int *fds,
int n_fds,
const DBusString *address,
DBusNonceFile *noncefile)
{
DBusServerSocket *socket_server;
DBusServer *server;
int i;
socket_server = dbus_new0 (DBusServerSocket, 1);
if (socket_server == NULL)
return NULL;
socket_server->noncefile = noncefile;
socket_server->fds = dbus_new (int, n_fds);
if (!socket_server->fds)
goto failed_0;
socket_server->watch = dbus_new0 (DBusWatch *, n_fds);
if (!socket_server->watch)
goto failed_1;
for (i = 0 ; i < n_fds ; i++)
{
DBusWatch *watch;
watch = _dbus_watch_new (fds[i],
DBUS_WATCH_READABLE,
TRUE,
socket_handle_watch, socket_server,
NULL);
if (watch == NULL)
goto failed_2;
socket_server->n_fds++;
socket_server->fds[i] = fds[i];
socket_server->watch[i] = watch;
}
if (!_dbus_server_init_base (&socket_server->base,
&socket_vtable, address))
goto failed_2;
server = (DBusServer*)socket_server;
SERVER_LOCK (server);
for (i = 0 ; i < n_fds ; i++)
{
if (!_dbus_server_add_watch (&socket_server->base,
socket_server->watch[i]))
{
int j;
for (j = 0 ; j < i ; j++)
_dbus_server_remove_watch (server,
socket_server->watch[j]);
SERVER_UNLOCK (server);
_dbus_server_finalize_base (&socket_server->base);
goto failed_2;
}
}
SERVER_UNLOCK (server);
return (DBusServer*) socket_server;
failed_2:
for (i = 0 ; i < n_fds ; i++)
{
if (socket_server->watch[i] != NULL)
{
_dbus_watch_unref (socket_server->watch[i]);
socket_server->watch[i] = NULL;
}
}
dbus_free (socket_server->watch);
failed_1:
dbus_free (socket_server->fds);
failed_0:
dbus_free (socket_server);
return NULL;
}
/**
* Creates a new transport for the given socket file descriptor. The file
* descriptor must be nonblocking (use _dbus_set_fd_nonblocking() to
* make it so). This function is shared by various transports that
* boil down to a full duplex file descriptor.
*
* @param fd the file descriptor.
* @param server_guid non-#NULL if this transport is on the server side of a connection
* @param address the transport's address
* @returns the new transport, or #NULL if no memory.
*/
DBusTransport*
_dbus_transport_new_for_socket (DBusSocket fd,
const DBusString *server_guid,
const DBusString *address)
{
DBusTransportSocket *socket_transport;
socket_transport = dbus_new0 (DBusTransportSocket, 1);
if (socket_transport == NULL)
return NULL;
if (!_dbus_string_init (&socket_transport->encoded_outgoing))
goto failed_0;
if (!_dbus_string_init (&socket_transport->encoded_incoming))
goto failed_1;
socket_transport->write_watch = _dbus_watch_new (_dbus_socket_get_pollable (fd),
DBUS_WATCH_WRITABLE,
FALSE,
NULL, NULL, NULL);
if (socket_transport->write_watch == NULL)
goto failed_2;
socket_transport->read_watch = _dbus_watch_new (_dbus_socket_get_pollable (fd),
DBUS_WATCH_READABLE,
FALSE,
NULL, NULL, NULL);
if (socket_transport->read_watch == NULL)
goto failed_3;
if (!_dbus_transport_init_base (&socket_transport->base,
&socket_vtable,
server_guid, address))
goto failed_4;
#ifdef HAVE_UNIX_FD_PASSING
_dbus_auth_set_unix_fd_possible(socket_transport->base.auth, _dbus_socket_can_pass_unix_fd(fd));
#endif
socket_transport->fd = fd;
socket_transport->message_bytes_written = 0;
/* These values should probably be tunable or something. */
socket_transport->max_bytes_read_per_iteration = 2048;
socket_transport->max_bytes_written_per_iteration = 2048;
return (DBusTransport*) socket_transport;
failed_4:
_dbus_watch_invalidate (socket_transport->read_watch);
_dbus_watch_unref (socket_transport->read_watch);
failed_3:
_dbus_watch_invalidate (socket_transport->write_watch);
_dbus_watch_unref (socket_transport->write_watch);
failed_2:
_dbus_string_free (&socket_transport->encoded_incoming);
failed_1:
_dbus_string_free (&socket_transport->encoded_outgoing);
failed_0:
dbus_free (socket_transport);
return NULL;
}
/**
* Spawns a new process.
*
* On Unix platforms, the child_setup function is passed the given
* user_data and is run in the child after fork() but before calling exec().
* This can be used to change uid, resource limits and so on.
* On Windows, this functionality does not fit the multi-processing model
* (Windows does the equivalent of fork() and exec() in a single API call),
* and the child_setup function and its user_data are ignored.
*
* Also creates a "babysitter" which tracks the status of the
* child process, advising the parent if the child exits.
* If the spawn fails, no babysitter is created.
* If sitter_p is #NULL, no babysitter is kept.
*
* @param sitter_p return location for babysitter or #NULL
* @param log_name the name under which to log messages about this process being spawned
* @param argv the executable and arguments
* @param env the environment, or #NULL to copy the parent's
* @param child_setup function to call in child pre-exec()
* @param user_data user data for setup function
* @param error error object to be filled in if function fails
* @returns #TRUE on success, #FALSE if error is filled in
*/
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)
{
DBusBabysitter *sitter;
int child_err_report_pipe[2] = { -1, -1 };
DBusSocket babysitter_pipe[2] = { DBUS_SOCKET_INIT, DBUS_SOCKET_INIT };
pid_t pid;
#ifdef HAVE_SYSTEMD
int fd_out = -1;
int fd_err = -1;
#endif
_DBUS_ASSERT_ERROR_IS_CLEAR (error);
_dbus_assert (argv[0] != NULL);
if (sitter_p != NULL)
*sitter_p = NULL;
sitter = NULL;
sitter = _dbus_babysitter_new ();
if (sitter == NULL)
{
dbus_set_error (error, DBUS_ERROR_NO_MEMORY, NULL);
return FALSE;
}
sitter->log_name = _dbus_strdup (log_name);
if (sitter->log_name == NULL && log_name != NULL)
{
dbus_set_error (error, DBUS_ERROR_NO_MEMORY, NULL);
goto cleanup_and_fail;
}
if (sitter->log_name == NULL)
sitter->log_name = _dbus_strdup (argv[0]);
if (sitter->log_name == NULL)
{
dbus_set_error (error, DBUS_ERROR_NO_MEMORY, NULL);
goto cleanup_and_fail;
}
if (!make_pipe (child_err_report_pipe, error))
goto cleanup_and_fail;
if (!_dbus_socketpair (&babysitter_pipe[0], &babysitter_pipe[1], TRUE, error))
goto cleanup_and_fail;
/* Setting up the babysitter is only useful in the parent,
* but we don't want to run out of memory and fail
* after we've already forked, since then we'd leak
* child processes everywhere.
*/
sitter->error_watch = _dbus_watch_new (child_err_report_pipe[READ_END],
DBUS_WATCH_READABLE,
TRUE, handle_watch, sitter, NULL);
if (sitter->error_watch == NULL)
{
dbus_set_error (error, DBUS_ERROR_NO_MEMORY, NULL);
goto cleanup_and_fail;
}
if (!_dbus_watch_list_add_watch (sitter->watches, sitter->error_watch))
{
/* we need to free it early so the destructor won't try to remove it
* without it having been added, which DBusLoop doesn't allow */
_dbus_watch_invalidate (sitter->error_watch);
_dbus_watch_unref (sitter->error_watch);
sitter->error_watch = NULL;
dbus_set_error (error, DBUS_ERROR_NO_MEMORY, NULL);
goto cleanup_and_fail;
}
sitter->sitter_watch = _dbus_watch_new (babysitter_pipe[0].fd,
DBUS_WATCH_READABLE,
TRUE, handle_watch, sitter, NULL);
if (sitter->sitter_watch == NULL)
{
dbus_set_error (error, DBUS_ERROR_NO_MEMORY, NULL);
goto cleanup_and_fail;
}
if (!_dbus_watch_list_add_watch (sitter->watches, sitter->sitter_watch))
{
/* we need to free it early so the destructor won't try to remove it
* without it having been added, which DBusLoop doesn't allow */
_dbus_watch_invalidate (sitter->sitter_watch);
_dbus_watch_unref (sitter->sitter_watch);
sitter->sitter_watch = NULL;
dbus_set_error (error, DBUS_ERROR_NO_MEMORY, NULL);
goto cleanup_and_fail;
}
_DBUS_ASSERT_ERROR_IS_CLEAR (error);
#ifdef HAVE_SYSTEMD
if (flags & DBUS_SPAWN_REDIRECT_OUTPUT)
{
/* This may fail, but it's not critical.
* In particular, if we were compiled with journald support but are now
* running on a non-systemd system, this is going to fail, so we
* have to cope gracefully. */
fd_out = sd_journal_stream_fd (sitter->log_name, LOG_INFO, FALSE);
fd_err = sd_journal_stream_fd (sitter->log_name, LOG_WARNING, FALSE);
}
#endif
pid = fork ();
if (pid < 0)
{
dbus_set_error (error,
DBUS_ERROR_SPAWN_FORK_FAILED,
"Failed to fork (%s)",
_dbus_strerror (errno));
goto cleanup_and_fail;
}
else if (pid == 0)
{
/* Immediate child, this is the babysitter process. */
int grandchild_pid;
/* Be sure we crash if the parent exits
* and we write to the err_report_pipe
*/
signal (SIGPIPE, SIG_DFL);
/* Close the parent's end of the pipes. */
close_and_invalidate (&child_err_report_pipe[READ_END]);
close_and_invalidate (&babysitter_pipe[0].fd);
/* Create the child that will exec () */
grandchild_pid = fork ();
if (grandchild_pid < 0)
{
write_err_and_exit (babysitter_pipe[1].fd,
CHILD_FORK_FAILED);
_dbus_assert_not_reached ("Got to code after write_err_and_exit()");
}
else if (grandchild_pid == 0)
{
#ifdef __linux__
int fd = -1;
#ifdef O_CLOEXEC
fd = open ("/proc/self/oom_score_adj", O_WRONLY | O_CLOEXEC);
#endif
if (fd < 0)
{
fd = open ("/proc/self/oom_score_adj", O_WRONLY);
_dbus_fd_set_close_on_exec (fd);
}
if (fd >= 0)
{
if (write (fd, "0", sizeof (char)) < 0)
_dbus_warn ("writing oom_score_adj error: %s", strerror (errno));
_dbus_close (fd, NULL);
}
#endif
/* Go back to ignoring SIGPIPE, since it's evil
*/
signal (SIGPIPE, SIG_IGN);
close_and_invalidate (&babysitter_pipe[1].fd);
#ifdef HAVE_SYSTEMD
/* log to systemd journal if possible */
if (fd_out >= 0)
dup2 (fd_out, STDOUT_FILENO);
if (fd_err >= 0)
dup2 (fd_err, STDERR_FILENO);
close_and_invalidate (&fd_out);
close_and_invalidate (&fd_err);
#endif
do_exec (child_err_report_pipe[WRITE_END],
argv,
env,
child_setup, user_data);
_dbus_assert_not_reached ("Got to code after exec() - should have exited on error");
}
else
{
close_and_invalidate (&child_err_report_pipe[WRITE_END]);
#ifdef HAVE_SYSTEMD
close_and_invalidate (&fd_out);
close_and_invalidate (&fd_err);
#endif
babysit (grandchild_pid, babysitter_pipe[1].fd);
_dbus_assert_not_reached ("Got to code after babysit()");
}
}
else
{
/* Close the uncared-about ends of the pipes */
close_and_invalidate (&child_err_report_pipe[WRITE_END]);
close_and_invalidate (&babysitter_pipe[1].fd);
#ifdef HAVE_SYSTEMD
close_and_invalidate (&fd_out);
close_and_invalidate (&fd_err);
#endif
sitter->socket_to_babysitter = babysitter_pipe[0];
babysitter_pipe[0].fd = -1;
sitter->error_pipe_from_child = child_err_report_pipe[READ_END];
child_err_report_pipe[READ_END] = -1;
sitter->sitter_pid = pid;
if (sitter_p != NULL)
*sitter_p = sitter;
else
_dbus_babysitter_unref (sitter);
dbus_free_string_array (env);
_DBUS_ASSERT_ERROR_IS_CLEAR (error);
return TRUE;
}
cleanup_and_fail:
_DBUS_ASSERT_ERROR_IS_SET (error);
close_and_invalidate (&child_err_report_pipe[READ_END]);
close_and_invalidate (&child_err_report_pipe[WRITE_END]);
close_and_invalidate (&babysitter_pipe[0].fd);
close_and_invalidate (&babysitter_pipe[1].fd);
#ifdef HAVE_SYSTEMD
close_and_invalidate (&fd_out);
close_and_invalidate (&fd_err);
#endif
if (sitter != NULL)
_dbus_babysitter_unref (sitter);
return FALSE;
}
/**
* Decrement the reference count on the babysitter object.
*
* @param sitter the babysitter
*/
void
_dbus_babysitter_unref (DBusBabysitter *sitter)
{
int i;
PING();
_dbus_assert (sitter != NULL);
_dbus_assert (sitter->refcount > 0);
sitter->refcount -= 1;
if (sitter->refcount == 0)
{
if (sitter->socket_to_babysitter != -1)
{
_dbus_close_socket (sitter->socket_to_babysitter, NULL);
sitter->socket_to_babysitter = -1;
}
if (sitter->socket_to_main != -1)
{
_dbus_close_socket (sitter->socket_to_main, NULL);
sitter->socket_to_main = -1;
}
PING();
if (sitter->argv != NULL)
{
for (i = 0; i < sitter->argc; i++)
if (sitter->argv[i] != NULL)
{
dbus_free (sitter->argv[i]);
sitter->argv[i] = NULL;
}
dbus_free (sitter->argv);
sitter->argv = NULL;
}
if (sitter->envp != NULL)
{
char **e = sitter->envp;
while (*e)
dbus_free (*e++);
dbus_free (sitter->envp);
sitter->envp = NULL;
}
if (sitter->child_handle != NULL)
{
CloseHandle (sitter->child_handle);
sitter->child_handle = NULL;
}
if (sitter->sitter_watch)
{
_dbus_watch_invalidate (sitter->sitter_watch);
_dbus_watch_unref (sitter->sitter_watch);
sitter->sitter_watch = NULL;
}
if (sitter->watches)
_dbus_watch_list_free (sitter->watches);
if (sitter->start_sync_event != NULL)
{
PING();
CloseHandle (sitter->start_sync_event);
sitter->start_sync_event = NULL;
}
#ifdef DBUS_BUILD_TESTS
if (sitter->end_sync_event != NULL)
{
CloseHandle (sitter->end_sync_event);
sitter->end_sync_event = NULL;
}
#endif
dbus_free (sitter->executable);
dbus_free (sitter);
}
}
/**
* Decrement the reference count on the babysitter object.
* When the reference count of the babysitter object reaches
* zero, the babysitter is killed and the child that was being
* babysat gets emancipated.
*
* @param sitter the babysitter
*/
void
_dbus_babysitter_unref (DBusBabysitter *sitter)
{
_dbus_assert (sitter != NULL);
_dbus_assert (sitter->refcount > 0);
sitter->refcount -= 1;
if (sitter->refcount == 0)
{
if (sitter->socket_to_babysitter >= 0)
{
/* If we haven't forked other babysitters
* since this babysitter and socket were
* created then this close will cause the
* babysitter to wake up from poll with
* a hangup and then the babysitter will
* quit itself.
*/
_dbus_close_socket (sitter->socket_to_babysitter, NULL);
sitter->socket_to_babysitter = -1;
}
if (sitter->error_pipe_from_child >= 0)
{
_dbus_close_socket (sitter->error_pipe_from_child, NULL);
sitter->error_pipe_from_child = -1;
}
if (sitter->sitter_pid > 0)
{
int status;
int ret;
/* It's possible the babysitter died on its own above
* from the close, or was killed randomly
* by some other process, so first try to reap it
*/
ret = waitpid (sitter->sitter_pid, &status, WNOHANG);
/* If we couldn't reap the child then kill it, and
* try again
*/
if (ret == 0)
kill (sitter->sitter_pid, SIGKILL);
again:
if (ret == 0)
ret = waitpid (sitter->sitter_pid, &status, 0);
if (ret < 0)
{
if (errno == EINTR)
goto again;
else if (errno == ECHILD)
_dbus_warn ("Babysitter process not available to be reaped; should not happen\n");
else
_dbus_warn ("Unexpected error %d in waitpid() for babysitter: %s\n",
errno, _dbus_strerror (errno));
}
else
{
_dbus_verbose ("Reaped %ld, waiting for babysitter %ld\n",
(long) ret, (long) sitter->sitter_pid);
if (WIFEXITED (sitter->status))
_dbus_verbose ("Babysitter exited with status %d\n",
WEXITSTATUS (sitter->status));
else if (WIFSIGNALED (sitter->status))
_dbus_verbose ("Babysitter received signal %d\n",
WTERMSIG (sitter->status));
else
_dbus_verbose ("Babysitter exited abnormally\n");
}
sitter->sitter_pid = -1;
}
if (sitter->error_watch)
{
_dbus_watch_invalidate (sitter->error_watch);
_dbus_watch_unref (sitter->error_watch);
sitter->error_watch = NULL;
}
if (sitter->sitter_watch)
{
_dbus_watch_invalidate (sitter->sitter_watch);
_dbus_watch_unref (sitter->sitter_watch);
sitter->sitter_watch = NULL;
}
if (sitter->watches)
_dbus_watch_list_free (sitter->watches);
dbus_free (sitter->executable);
dbus_free (sitter);
}
}
/**
* Spawns a new process. The executable name and argv[0]
* are the same, both are provided in argv[0]. The child_setup
* function is passed the given user_data and is run in the child
* just before calling exec().
*
* Also creates a "babysitter" which tracks the status of the
* child process, advising the parent if the child exits.
* If the spawn fails, no babysitter is created.
* If sitter_p is #NULL, no babysitter is kept.
*
* @param sitter_p return location for babysitter or #NULL
* @param argv the executable and arguments
* @param env the environment (not used on unix yet)
* @param child_setup function to call in child pre-exec()
* @param user_data user data for setup function
* @param error error object to be filled in if function fails
* @returns #TRUE on success, #FALSE if error is filled in
*/
dbus_bool_t
_dbus_spawn_async_with_babysitter (DBusBabysitter **sitter_p,
char **argv,
char **env,
DBusSpawnChildSetupFunc child_setup,
void *user_data,
DBusError *error)
{
DBusBabysitter *sitter;
int child_err_report_pipe[2] = { -1, -1 };
int babysitter_pipe[2] = { -1, -1 };
pid_t pid;
_DBUS_ASSERT_ERROR_IS_CLEAR (error);
if (sitter_p != NULL)
*sitter_p = NULL;
sitter = NULL;
sitter = _dbus_babysitter_new ();
if (sitter == NULL)
{
dbus_set_error (error, DBUS_ERROR_NO_MEMORY, NULL);
return FALSE;
}
sitter->executable = _dbus_strdup (argv[0]);
if (sitter->executable == NULL)
{
dbus_set_error (error, DBUS_ERROR_NO_MEMORY, NULL);
goto cleanup_and_fail;
}
if (!make_pipe (child_err_report_pipe, error))
goto cleanup_and_fail;
if (!_dbus_full_duplex_pipe (&babysitter_pipe[0], &babysitter_pipe[1], TRUE, error))
goto cleanup_and_fail;
/* Setting up the babysitter is only useful in the parent,
* but we don't want to run out of memory and fail
* after we've already forked, since then we'd leak
* child processes everywhere.
*/
sitter->error_watch = _dbus_watch_new (child_err_report_pipe[READ_END],
DBUS_WATCH_READABLE,
TRUE, handle_watch, sitter, NULL);
if (sitter->error_watch == NULL)
{
dbus_set_error (error, DBUS_ERROR_NO_MEMORY, NULL);
goto cleanup_and_fail;
}
if (!_dbus_watch_list_add_watch (sitter->watches, sitter->error_watch))
{
/* we need to free it early so the destructor won't try to remove it
* without it having been added, which DBusLoop doesn't allow */
_dbus_watch_invalidate (sitter->error_watch);
_dbus_watch_unref (sitter->error_watch);
sitter->error_watch = NULL;
dbus_set_error (error, DBUS_ERROR_NO_MEMORY, NULL);
goto cleanup_and_fail;
}
sitter->sitter_watch = _dbus_watch_new (babysitter_pipe[0],
DBUS_WATCH_READABLE,
TRUE, handle_watch, sitter, NULL);
if (sitter->sitter_watch == NULL)
{
dbus_set_error (error, DBUS_ERROR_NO_MEMORY, NULL);
goto cleanup_and_fail;
}
if (!_dbus_watch_list_add_watch (sitter->watches, sitter->sitter_watch))
{
/* we need to free it early so the destructor won't try to remove it
* without it having been added, which DBusLoop doesn't allow */
_dbus_watch_invalidate (sitter->sitter_watch);
_dbus_watch_unref (sitter->sitter_watch);
sitter->sitter_watch = NULL;
dbus_set_error (error, DBUS_ERROR_NO_MEMORY, NULL);
goto cleanup_and_fail;
}
_DBUS_ASSERT_ERROR_IS_CLEAR (error);
pid = fork ();
if (pid < 0)
{
dbus_set_error (error,
DBUS_ERROR_SPAWN_FORK_FAILED,
"Failed to fork (%s)",
_dbus_strerror (errno));
goto cleanup_and_fail;
}
else if (pid == 0)
{
/* Immediate child, this is the babysitter process. */
int grandchild_pid;
/* Be sure we crash if the parent exits
* and we write to the err_report_pipe
*/
signal (SIGPIPE, SIG_DFL);
/* Close the parent's end of the pipes. */
close_and_invalidate (&child_err_report_pipe[READ_END]);
close_and_invalidate (&babysitter_pipe[0]);
/* Create the child that will exec () */
grandchild_pid = fork ();
if (grandchild_pid < 0)
{
write_err_and_exit (babysitter_pipe[1],
CHILD_FORK_FAILED);
_dbus_assert_not_reached ("Got to code after write_err_and_exit()");
}
else if (grandchild_pid == 0)
{
do_exec (child_err_report_pipe[WRITE_END],
argv,
env,
child_setup, user_data);
_dbus_assert_not_reached ("Got to code after exec() - should have exited on error");
}
else
{
babysit (grandchild_pid, babysitter_pipe[1]);
_dbus_assert_not_reached ("Got to code after babysit()");
}
}
else
{
/* Close the uncared-about ends of the pipes */
close_and_invalidate (&child_err_report_pipe[WRITE_END]);
close_and_invalidate (&babysitter_pipe[1]);
sitter->socket_to_babysitter = babysitter_pipe[0];
babysitter_pipe[0] = -1;
sitter->error_pipe_from_child = child_err_report_pipe[READ_END];
child_err_report_pipe[READ_END] = -1;
sitter->sitter_pid = pid;
if (sitter_p != NULL)
*sitter_p = sitter;
else
_dbus_babysitter_unref (sitter);
dbus_free_string_array (env);
_DBUS_ASSERT_ERROR_IS_CLEAR (error);
return TRUE;
}
cleanup_and_fail:
_DBUS_ASSERT_ERROR_IS_SET (error);
close_and_invalidate (&child_err_report_pipe[READ_END]);
close_and_invalidate (&child_err_report_pipe[WRITE_END]);
close_and_invalidate (&babysitter_pipe[0]);
close_and_invalidate (&babysitter_pipe[1]);
if (sitter != NULL)
_dbus_babysitter_unref (sitter);
return FALSE;
}
