service: add options RestartPreventExitStatus and SuccessExitStatus

In some cases, like wrong configuration, restarting after error
does not help, so administrator can specify statuses by RestartPreventExitStatus
which will not cause restart of a service.

Sometimes you have non-standart exit status, so this can be specified
by SuccessfulExitStatus.

src/core/load-fragment-gperf.gperf.m4

@@ -158,6 +158,8 @@ Service.PermissionsStartOnly,    config_parse_bool,                  0,
 Service.RootDirectoryStartOnly,  config_parse_bool,                  0,                             offsetof(Service, root_directory_start_only)
 Service.RemainAfterExit,         config_parse_bool,                  0,                             offsetof(Service, remain_after_exit)
 Service.GuessMainPID,            config_parse_bool,                  0,                             offsetof(Service, guess_main_pid)
+Service.RestartPreventExitStatus, config_parse_set_status,           0,                             offsetof(Service, restart_ignore_status)
+Service.SuccessExitStatus,       config_parse_set_status,            0,                             offsetof(Service, success_status)
 m4_ifdef(`HAVE_SYSV_COMPAT',
 `Service.SysVStartPriority,      config_parse_sysv_priority,         0,                             offsetof(Service, sysv_start_priority)',
 `Service.SysVStartPriority,      config_parse_warn_compat,           0,                             0')

src/core/mount.c

@@ -1225,7 +1225,7 @@ static void mount_sigchld_event(Unit *u, pid_t pid, int code, int status) {
 
         m->control_pid = 0;
 
-        if (is_clean_exit(code, status))
+        if (is_clean_exit(code, status, NULL))
                 f = MOUNT_SUCCESS;
         else if (code == CLD_EXITED)
                 f = MOUNT_FAILURE_EXIT_CODE;

src/core/service.c

@@ -294,6 +294,16 @@ static void service_done(Unit *u) {
         s->control_command = NULL;
         s->main_command = NULL;
 
+        set_free(s->restart_ignore_status.code);
+        s->restart_ignore_status.code = NULL;
+        set_free(s->restart_ignore_status.signal);
+        s->restart_ignore_status.signal = NULL;
+
+        set_free(s->success_status.code);
+        s->success_status.code = NULL;
+        set_free(s->success_status.signal);
+        s->success_status.signal = NULL;
+
         /* This will leak a process, but at least no memory or any of
          * our resources */
         service_unwatch_main_pid(s);
@@ -1902,7 +1912,12 @@ static void service_enter_dead(Service *s, ServiceResult f, bool allow_restart)
              (s->restart == SERVICE_RESTART_ON_SUCCESS && s->result == SERVICE_SUCCESS) ||
              (s->restart == SERVICE_RESTART_ON_FAILURE && s->result != SERVICE_SUCCESS) ||
              (s->restart == SERVICE_RESTART_ON_ABORT && (s->result == SERVICE_FAILURE_SIGNAL ||
-                                                         s->result == SERVICE_FAILURE_CORE_DUMP)))) {
+                                                         s->result == SERVICE_FAILURE_CORE_DUMP))) &&
+            (s->result != SERVICE_FAILURE_EXIT_CODE ||
+             !set_contains(s->restart_ignore_status.code, INT_TO_PTR(s->main_exec_status.status))) &&
+            (s->result != SERVICE_FAILURE_SIGNAL ||
+             !set_contains(s->restart_ignore_status.signal, INT_TO_PTR(s->main_exec_status.status)))
+                ) {
 
                 r = unit_watch_timer(UNIT(s), s->restart_usec, &s->timer_watch);
                 if (r < 0)
@@ -2874,7 +2889,8 @@ static void service_sigchld_event(Unit *u, pid_t pid, int code, int status) {
         assert(s);
         assert(pid >= 0);
 
-        if (UNIT(s)->fragment_path ? is_clean_exit(code, status) : is_clean_exit_lsb(code, status))
+        if (UNIT(s)->fragment_path ? is_clean_exit(code, status, &s->success_status) :
+                                     is_clean_exit_lsb(code, status, &s->success_status))
                 f = SERVICE_SUCCESS;
         else if (code == CLD_EXITED)
                 f = SERVICE_FAILURE_EXIT_CODE;

src/core/service.h

@@ -28,6 +28,7 @@ typedef struct Service Service;
 #include "ratelimit.h"
 #include "service.h"
 #include "kill.h"
+#include "exit-status.h"
 
 typedef enum ServiceState {
         SERVICE_DEAD,
@@ -115,6 +116,8 @@ struct Service {
 
         ServiceType type;
         ServiceRestart restart;
+        ExitStatusSet restart_ignore_status;
+        ExitStatusSet success_status;
 
         /* If set we'll read the main daemon PID from this file */
         char *pid_file;

src/core/socket.c

@@ -1884,7 +1884,7 @@ static void socket_sigchld_event(Unit *u, pid_t pid, int code, int status) {
 
         s->control_pid = 0;
 
-        if (is_clean_exit(code, status))
+        if (is_clean_exit(code, status, NULL))
                 f = SOCKET_SUCCESS;
         else if (code == CLD_EXITED)
                 f = SOCKET_FAILURE_EXIT_CODE;

src/core/swap.c

@@ -917,7 +917,7 @@ static void swap_sigchld_event(Unit *u, pid_t pid, int code, int status) {
 
         s->control_pid = 0;
 
-        if (is_clean_exit(code, status))
+        if (is_clean_exit(code, status, NULL))
                 f = SWAP_SUCCESS;
         else if (code == CLD_EXITED)
                 f = SWAP_FAILURE_EXIT_CODE;