util: Add error handling to become_daemon()

[samba.git] / lib / util / become_daemon.c

diff --git a/lib/util/become_daemon.c b/lib/util/become_daemon.c
index 373927ca6ea95def39716e5aae4189e54897e7b9..22c1778d4a461b9c7aef9afebb7cf5c0d49ee731 100644 (file)
--- a/lib/util/become_daemon.c
+++ b/lib/util/become_daemon.c
@@ -21,70 +21,78 @@
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-#include "includes.h"
+#include "replace.h"
 #include "system/filesys.h"
 #include "system/locale.h"
+#if defined(HAVE_LIBSYSTEMD_DAEMON) || defined(HAVE_LIBSYSTEMD)
+#include <systemd/sd-daemon.h>
+#endif
+
+#include "close_low_fd.h"
+#include "debug.h"
+
+#include "become_daemon.h"
 
 /*******************************************************************
  Close the low 3 fd's and open dev/null in their place.
 ********************************************************************/
 
-_PUBLIC_ void close_low_fds(bool stdin_too, bool stdout_too, bool stderr_too)
+void close_low_fds(bool stdin_too, bool stdout_too, bool stderr_too)
 {
-#ifndef VALGRIND
-       int fd;
-       int i;
-
-       if (stdin_too)
-               close(0);
-       if (stdout_too)
-               close(1);
 
-       if (stderr_too)
-               close(2);
-
-       /* try and use up these file descriptors, so silly
-               library routines writing to stdout etc won't cause havoc */
-       for (i=0;i<3;i++) {
-               if (i == 0 && !stdin_too)
-                       continue;
-               if (i == 1 && !stdout_too)
-                       continue;
-               if (i == 2 && !stderr_too)
-                       continue;
-
-               fd = open("/dev/null",O_RDWR,0);
-               if (fd < 0)
-                       fd = open("/dev/null",O_WRONLY,0);
-               if (fd < 0) {
-                       DEBUG(0,("Can't open /dev/null\n"));
-                       return;
+       if (stdin_too) {
+               int ret = close_low_fd(0);
+               if (ret != 0) {
+                       DBG_ERR("close_low_fd(0) failed: %s\n", strerror(ret));
                }
-               if (fd != i) {
-                       DEBUG(0,("Didn't get file descriptor %d\n",i));
-                       return;
+       }
+       if (stdout_too) {
+               int ret = close_low_fd(1);
+               if (ret != 0) {
+                       DBG_ERR("close_low_fd(1) failed: %s\n", strerror(ret));
+               }
+       }
+       if (stderr_too) {
+               int ret = close_low_fd(2);
+               if (ret != 0) {
+                       DBG_ERR("close_low_fd(2) failed: %s\n", strerror(ret));
                }
        }
-#endif
 }
 
 /****************************************************************************
  Become a daemon, discarding the controlling terminal.
 ****************************************************************************/
 
-_PUBLIC_ void become_daemon(bool do_fork, bool no_process_group, bool log_stdout)
+void become_daemon(bool do_fork, bool no_session, bool log_stdout)
 {
+       pid_t newpid;
        if (do_fork) {
-               if (fork()) {
+               newpid = fork();
+               if (newpid == -1) {
+                       exit_daemon("Fork failed", errno);
+               }
+               if (newpid) {
+#if defined(HAVE_LIBSYSTEMD_DAEMON) || defined(HAVE_LIBSYSTEMD)
+                       sd_notifyf(0,
+                                  "READY=0\nSTATUS=Starting process...\n"
+                                  "MAINPID=%lu",
+                                  (unsigned long) newpid);
+#endif /* HAVE_LIBSYSTEMD_DAEMON */
                        _exit(0);
                }
        }
 
        /* detach from the terminal */
 #ifdef HAVE_SETSID
-       if (!no_process_group) setsid();
+       if (!no_session) {
+               int ret = setsid();
+               if (ret == -1) {
+                       exit_daemon("Failed to create session", errno);
+               }
+       }
 #elif defined(TIOCNOTTY)
-       if (!no_process_group) {
+       if (!no_session) {
                int i = open("/dev/tty", O_RDWR, 0);
                if (i != -1) {
                        ioctl(i, (int) TIOCNOTTY, (char *)0);
@@ -99,3 +107,44 @@ _PUBLIC_ void become_daemon(bool do_fork, bool no_process_group, bool log_stdout
         * never close stderr (but debug might dup it onto a log file) */
        close_low_fds(do_fork, !log_stdout, false);
 }
+
+void exit_daemon(const char *msg, int error)
+{
+#if defined(HAVE_LIBSYSTEMD_DAEMON) || defined(HAVE_LIBSYSTEMD)
+       if (msg == NULL) {
+               msg = strerror(error);
+       }
+
+       sd_notifyf(0, "STATUS=daemon failed to start: %s\n"
+                                 "ERRNO=%i",
+                                 msg,
+                                 error);
+#endif
+       DBG_ERR("STATUS=daemon failed to start: %s, error code %d\n",
+               msg, error);
+       exit(1);
+}
+
+void daemon_ready(const char *daemon)
+{
+       if (daemon == NULL) {
+               daemon = "Samba";
+       }
+#if defined(HAVE_LIBSYSTEMD_DAEMON) || defined(HAVE_LIBSYSTEMD)
+       sd_notifyf(0, "READY=1\nSTATUS=%s: ready to serve connections...",
+                  daemon);
+#endif
+       DBG_ERR("STATUS=daemon '%s' finished starting up and ready to serve "
+               "connections\n", daemon);
+}
+
+void daemon_status(const char *daemon, const char *msg)
+{
+       if (daemon == NULL) {
+               daemon = "Samba";
+       }
+#if defined(HAVE_LIBSYSTEMD_DAEMON) || defined(HAVE_LIBSYSTEMD)
+       sd_notifyf(0, "\nSTATUS=%s: %s", daemon, msg);
+#endif
+       DBG_ERR("STATUS=daemon '%s' : %s", daemon, msg);
+}