/**
* 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;
}
static int fork_child_async(const char* cmd, int* child_pid) {
pid_t pid, grandchild_pid;
int child_pid_report_pipe[2] = {-1, -1};
int child_err_report_pipe[2] = {-1, -1};
int null_dev;
/* by default is assumed how command wasn't found */
int ret = RUN_NOT_FOUND;
errno = 0;
if(pipe(child_pid_report_pipe) != 0) {
E_WARNING(E_STRLOC ": pipe() failed with '%s'\n", strerror(errno));
return RUN_PIPE_FAILED;
}
if(pipe(child_err_report_pipe) != 0) {
E_WARNING(E_STRLOC ": pipe() failed with '%s'\n", strerror(errno));
return RUN_PIPE_FAILED;
}
pid = fork();
if(pid < 0) {
E_WARNING(E_STRLOC ": fork() failed with '%s'\n", strerror(errno));
return RUN_FORK_FAILED;
} else if(pid == 0) {
signal(SIGPIPE, SIG_DFL);
close_and_invalidate(&child_pid_report_pipe[0]);
close_and_invalidate(&child_err_report_pipe[0]);
/* TODO stdin, stdout, stderr */
grandchild_pid = fork();
if(grandchild_pid < 0) {
/* report -1 as returned value */
write_int(child_pid_report_pipe[1], grandchild_pid);
write_int(child_err_report_pipe[1], RUN_FORK_FAILED);
_exit(1);
} else if(grandchild_pid == 0) {
/*
* second child code is here; from now on every error
* is reported via pipe
*/
null_dev = open("/dev/null", O_RDWR);
if(null_dev == -1) {
write_int(child_pid_report_pipe[1], grandchild_pid);
write_int(child_err_report_pipe[1], errno);
_exit(1);
}
/* close on exec */
fcntl(child_err_report_pipe[1], F_SETFD, FD_CLOEXEC);
/* just send stdin, stdout, stderr to null dev */
close(0);
dup(null_dev);
close(1);
dup(null_dev);
close(2);
dup(null_dev);
exec_cmd(cmd, child_err_report_pipe[1]);
} else {
/* child (a grandchild parent) is here; report it's pid before normal exit */
write_int(child_pid_report_pipe[1], grandchild_pid);
close_and_invalidate(&child_err_report_pipe[1]);
_exit(0);
}
} else {
/* parent */
int status, buf[2], n_ints = 0;
close_and_invalidate(&child_pid_report_pipe[1]);
close_and_invalidate(&child_err_report_pipe[1]);
/* reap intermediate child */
while(waitpid(pid, &status, 0) < 0) {
if(errno == EINTR)
continue;
break;
}
if(!read_ints(child_err_report_pipe[0], buf, 2, &n_ints))
goto fail;
/* child signaled some error; inspect it and bail out */
if(n_ints >= 2) {
ret = convert_from_errno(buf[1], buf[0]);
goto fail;
}
/* get pid from grandchild pid, this is the pid of actual forked program */
n_ints = 0;
if(!read_ints(child_pid_report_pipe[0], buf, 1, &n_ints)) {
ret = RUN_PIPE_FAILED;
goto fail;
}
if(n_ints < 1) {
ret = RUN_PIPE_FAILED;
goto fail;
}
if(child_pid)
*child_pid = buf[0];
close_and_invalidate(&child_err_report_pipe[0]);
close_and_invalidate(&child_pid_report_pipe[0]);
/* everything went fine */
return 0;
}
fail:
/* we got some error in first child; reap it so it does not become a zombie */
if(pid > 0) {
while(waitpid(pid, NULL, 0) < 0) {
if(errno != EINTR)
break;
}
}
close_and_invalidate(&child_pid_report_pipe[0]);
close_and_invalidate(&child_pid_report_pipe[1]);
close_and_invalidate(&child_err_report_pipe[0]);
close_and_invalidate(&child_err_report_pipe[1]);
return ret;
}
/**
* 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;
}
EXPORT_C
#endif
dbus_bool_t
_dbus_spawn_async_with_babysitter (DBusBabysitter **sitter_p,
char **argv,
DBusSpawnChildSetupFunc child_setup,
void *user_data,
DBusError *error)
{
#ifndef __SYMBIAN32__
DBusBabysitter *sitter;
int child_err_report_pipe[2] = { -1, -1 };
int babysitter_pipe[2] = { -1, -1 };
pid_t pid;
#ifndef __SYMBIAN32__
_DBUS_ASSERT_ERROR_IS_CLEAR (error);
*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;
_dbus_fd_set_close_on_exec (child_err_report_pipe[READ_END]);
_dbus_fd_set_close_on_exec (child_err_report_pipe[WRITE_END]);
if (!_dbus_full_duplex_pipe (&babysitter_pipe[0], &babysitter_pipe[1], TRUE, error))
goto cleanup_and_fail;
_dbus_fd_set_close_on_exec (babysitter_pipe[0]);
_dbus_fd_set_close_on_exec (babysitter_pipe[1]);
/* 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))
{
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))
{
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
*/
#ifndef __SYMBIAN32__
signal (SIGPIPE, SIG_DFL);
#endif
/* 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,
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_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);
#endif
return FALSE;
#else
/*
FILE* ChildProcessStream;
ChildProcessStream =popen(argv[0], "r");
if (ChildProcessStream == NULL)
{
dbus_set_error (error, DBUS_ERROR_SPAWN_EXEC_FAILED,
"Failed to execute service process");
return FALSE;
}
*/
//static pid_t Childpid; //have to make it static for thread fuction to access it
pid_t childPid;
int retVal;
//pthread_t thread;
retVal = posix_spawn(&childPid, argv[0], NULL,NULL, NULL, NULL);
if (retVal!=0)
{
dbus_set_error (error, DBUS_ERROR_SPAWN_EXEC_FAILED,
"Failed to execute service process");
return FALSE;
}
/*
pthread_create(&thread, NULL, (void*)&thread_fun, &Childpid);
//(void) waitpid(Childpid, NULL, 0);
//printf("\r\n*** Child process finished ***\r\n");
*/
if(!retVal)
return TRUE;
else
return FALSE;
#endif
}
