Log that we received control messages.
[nssm.git] / service.cpp
index 05ca7cd..fd25163 100644 (file)
@@ -2,17 +2,34 @@
 \r
 SERVICE_STATUS service_status;\r
 SERVICE_STATUS_HANDLE service_handle;\r
+HANDLE process_handle;\r
 HANDLE wait_handle;\r
-HANDLE pid;\r
-char exe[MAX_PATH];\r
-char flags[MAX_PATH];\r
+unsigned long pid;\r
+static char service_name[SERVICE_NAME_LENGTH];\r
+char exe[EXE_LENGTH];\r
+char flags[CMD_LENGTH];\r
 char dir[MAX_PATH];\r
+bool stopping;\r
+unsigned long throttle_delay;\r
+HANDLE throttle_timer;\r
+LARGE_INTEGER throttle_duetime;\r
+\r
+static enum { NSSM_EXIT_RESTART, NSSM_EXIT_IGNORE, NSSM_EXIT_REALLY, NSSM_EXIT_UNCLEAN } exit_actions;\r
+static const char *exit_action_strings[] = { "Restart", "Ignore", "Exit", "Suicide", 0 };\r
+\r
+static unsigned long throttle;\r
+\r
+static inline int throttle_milliseconds() {\r
+  /* pow() operates on doubles. */\r
+  int ret = 1; for (unsigned long i = 1; i < throttle; i++) ret *= 2;\r
+  return ret * 1000;\r
+}\r
 \r
 /* Connect to the service manager */\r
 SC_HANDLE open_service_manager() {\r
   SC_HANDLE ret = OpenSCManager(0, SERVICES_ACTIVE_DATABASE, SC_MANAGER_ALL_ACCESS);\r
   if (! ret) {\r
-    eventprintf(EVENTLOG_ERROR_TYPE, "Unable to connect to service manager!\nPerhaps you need to be an administrator...");\r
+    log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_OPENSCMANAGER_FAILED, 0);\r
     return 0;\r
   }\r
 \r
@@ -26,8 +43,31 @@ int pre_install_service(int argc, char **argv) {
 \r
   /* Arguments are optional */\r
   char *flags;\r
-  if (argc == 2) flags = "";\r
-  else flags = argv[2];\r
+  size_t flagslen = 0;\r
+  size_t s = 0;\r
+  int i;\r
+  for (i = 2; i < argc; i++) flagslen += strlen(argv[i]) + 1;\r
+  if (! flagslen) flagslen = 1;\r
+\r
+  flags = (char *) HeapAlloc(GetProcessHeap(), 0, flagslen);\r
+  if (! flags) {\r
+    log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_OUT_OF_MEMORY, "flags", "pre_install_service()", 0);\r
+    return 2;\r
+  }\r
+  ZeroMemory(flags, flagslen);\r
+\r
+  /*\r
+    This probably isn't UTF8-safe and should use std::string or something\r
+    but it's been broken for the best part of a decade and due for a rewrite\r
+    anyway so it'll do as a quick-'n'-dirty fix.  Note that we don't free\r
+    the flags buffer but as the program exits that isn't a big problem.\r
+  */\r
+  for (i = 2; i < argc; i++) {\r
+    size_t len = strlen(argv[i]);\r
+    memmove(flags + s, argv[i], len);\r
+    s += len;\r
+    if (i < argc - 1) flags[s++] = ' ';\r
+  }\r
 \r
   return install_service(argv[0], argv[1], flags);\r
 }\r
@@ -55,21 +95,20 @@ int install_service(char *name, char *exe, char *flags) {
   GetModuleFileName(0, path, MAX_PATH);\r
 \r
   /* Construct command */\r
-  char command[MAX_PATH];\r
-  int runlen = strlen(NSSM_RUN);\r
-  int pathlen = strlen(path);\r
-  if (pathlen + runlen + 2 >= MAX_PATH) {\r
+  char command[CMD_LENGTH];\r
+  size_t pathlen = strlen(path);\r
+  if (pathlen + 1 >= VALUE_LENGTH) {\r
     fprintf(stderr, "The full path to " NSSM " is too long!\n");\r
     return 3;\r
   }\r
-  if (snprintf(command, sizeof(command), "\"%s\" %s", path, NSSM_RUN) < 0) {\r
+  if (_snprintf(command, sizeof(command), "\"%s\"", path) < 0) {\r
     fprintf(stderr, "Out of memory for ImagePath!\n");\r
     return 4;\r
   }\r
 \r
   /* Work out directory name */\r
-  unsigned int len = strlen(exe);\r
-  unsigned int i;\r
+  size_t len = strlen(exe);\r
+  size_t i;\r
   for (i = len; i && exe[i] != '\\' && exe[i] != '/'; i--);\r
   char dir[MAX_PATH];\r
   memmove(dir, exe, i);\r
@@ -134,69 +173,169 @@ int remove_service(char *name) {
 \r
 /* Service initialisation */\r
 void WINAPI service_main(unsigned long argc, char **argv) {\r
+  if (_snprintf(service_name, sizeof(service_name), "%s", argv[0]) < 0) {\r
+    log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_OUT_OF_MEMORY, "service_name", "service_main()", 0);\r
+    return;\r
+  }\r
+\r
   /* Initialise status */\r
   ZeroMemory(&service_status, sizeof(service_status));\r
   service_status.dwServiceType = SERVICE_WIN32_OWN_PROCESS | SERVICE_INTERACTIVE_PROCESS;\r
-  service_status.dwCurrentState = SERVICE_RUNNING;\r
-  service_status.dwControlsAccepted = SERVICE_ACCEPT_SHUTDOWN | SERVICE_ACCEPT_STOP;\r
+  service_status.dwControlsAccepted = SERVICE_ACCEPT_SHUTDOWN | SERVICE_ACCEPT_STOP | SERVICE_ACCEPT_PAUSE_CONTINUE;\r
   service_status.dwWin32ExitCode = NO_ERROR;\r
   service_status.dwServiceSpecificExitCode = 0;\r
   service_status.dwCheckPoint = 0;\r
-  service_status.dwWaitHint = 1000;\r
+  service_status.dwWaitHint = NSSM_WAITHINT_MARGIN;\r
 \r
   /* Signal we AREN'T running the server */\r
+  process_handle = 0;\r
   pid = 0;\r
 \r
-  /* Get startup parameters */\r
-  int ret = get_parameters(argv[0], exe, sizeof(exe), flags, sizeof(flags), dir, sizeof(dir));\r
-  if (ret) {\r
-    eventprintf(EVENTLOG_ERROR_TYPE, "service_main(): Can't get startup parameters: error %d", ret);\r
-    return;\r
-  }\r
-\r
   /* Register control handler */\r
   service_handle = RegisterServiceCtrlHandlerEx(NSSM, service_control_handler, 0);\r
   if (! service_handle) {\r
-    eventprintf(EVENTLOG_ERROR_TYPE, "service_main(): RegisterServiceCtrlHandlerEx() failed: %s", error_string(GetLastError()));\r
+    log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_REGISTERSERVICECTRLHANDER_FAILED, error_string(GetLastError()), 0);\r
     return;\r
   }\r
 \r
+  log_service_control(service_name, 0, true);\r
+\r
+  service_status.dwCurrentState = SERVICE_START_PENDING;\r
+  service_status.dwWaitHint = throttle_delay + NSSM_WAITHINT_MARGIN;\r
+  SetServiceStatus(service_handle, &service_status);\r
+\r
+  /* Try to create the exit action parameters; we don't care if it fails */\r
+  create_exit_action(argv[0], exit_action_strings[0]);\r
+\r
+  set_service_recovery(service_name);\r
+\r
+  /* Used for signalling a resume if the service pauses when throttled. */\r
+  throttle_timer = CreateWaitableTimer(0, 1, 0);\r
+  if (! throttle_timer) {\r
+    log_event(EVENTLOG_WARNING_TYPE, NSSM_EVENT_CREATEWAITABLETIMER_FAILED, service_name, error_string(GetLastError()), 0);\r
+  }\r
+\r
   monitor_service();\r
 }\r
 \r
+/* Make sure service recovery actions are taken where necessary */\r
+void set_service_recovery(char *service_name) {\r
+  SC_HANDLE services = open_service_manager();\r
+  if (! services) return;\r
+\r
+  SC_HANDLE service = OpenService(services, service_name, SC_MANAGER_ALL_ACCESS);\r
+  if (! service) return;\r
+  return;\r
+\r
+  SERVICE_FAILURE_ACTIONS_FLAG flag;\r
+  ZeroMemory(&flag, sizeof(flag));\r
+  flag.fFailureActionsOnNonCrashFailures = true;\r
+\r
+  /* This functionality was added in Vista so the call may fail */\r
+  ChangeServiceConfig2(service, SERVICE_CONFIG_FAILURE_ACTIONS_FLAG, &flag);\r
+}\r
+\r
 int monitor_service() {\r
   /* Set service status to started */\r
   int ret = start_service();\r
   if (ret) {\r
-    eventprintf(EVENTLOG_ERROR_TYPE, "Can't start service: error code %d", ret);\r
+    char code[16];\r
+    _snprintf(code, sizeof(code), "%d", ret);\r
+    log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_START_SERVICE_FAILED, exe, service_name, ret, 0);\r
     return ret;\r
   }\r
-  eventprintf(EVENTLOG_INFORMATION_TYPE, "Started process %s %s in %s", exe, flags, dir);\r
+  log_event(EVENTLOG_INFORMATION_TYPE, NSSM_EVENT_STARTED_SERVICE, exe, flags, service_name, dir, 0);\r
 \r
   /* Monitor service service */\r
-  if (! RegisterWaitForSingleObject(&wait_handle, pid, end_service, 0, INFINITE, WT_EXECUTEONLYONCE | WT_EXECUTELONGFUNCTION)) {\r
-    eventprintf(EVENTLOG_WARNING_TYPE, "RegisterWaitForSingleObject() returned %s - service may claim to be still running when %s exits ", error_string(GetLastError()), exe);\r
+  if (! RegisterWaitForSingleObject(&wait_handle, process_handle, end_service, (void *) pid, INFINITE, WT_EXECUTEONLYONCE | WT_EXECUTELONGFUNCTION)) {\r
+    log_event(EVENTLOG_WARNING_TYPE, NSSM_EVENT_REGISTERWAITFORSINGLEOBJECT_FAILED, service_name, exe, error_string(GetLastError()), 0);\r
   }\r
 \r
   return 0;\r
 }\r
 \r
+char *service_control_text(unsigned long control) {\r
+  switch (control) {\r
+    /* HACK: there is no SERVICE_CONTROL_START constant */\r
+    case 0: return "START";\r
+    case SERVICE_CONTROL_STOP: return "STOP";\r
+    case SERVICE_CONTROL_SHUTDOWN: return "SHUTDOWN";\r
+    case SERVICE_CONTROL_PAUSE: return "PAUSE";\r
+    case SERVICE_CONTROL_CONTINUE: return "CONTINUE";\r
+    case SERVICE_CONTROL_INTERROGATE: return "INTERROGATE";\r
+    default: return 0;\r
+  }\r
+}\r
+\r
+void log_service_control(char *service_name, unsigned long control, bool handled) {\r
+  char *text = service_control_text(control);\r
+  unsigned long event;\r
+\r
+  if (! text) {\r
+    /* "0x" + 8 x hex + NULL */\r
+    text = (char *) HeapAlloc(GetProcessHeap(), 0, 11);\r
+    if (! text) {\r
+      log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_OUT_OF_MEMORY, "control code", "log_service_control", 0);\r
+      return;\r
+    }\r
+    if (_snprintf(text, 11, "0x%08x", control) < 0) {\r
+      log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_OUT_OF_MEMORY, "control code", "log_service_control", 0);\r
+      HeapFree(GetProcessHeap(), 0, text);\r
+      return;\r
+    }\r
+\r
+    event = NSSM_EVENT_SERVICE_CONTROL_UNKNOWN;\r
+  }\r
+  else if (handled) event = NSSM_EVENT_SERVICE_CONTROL_HANDLED;\r
+  else event = NSSM_EVENT_SERVICE_CONTROL_NOT_HANDLED;\r
+\r
+  log_event(EVENTLOG_INFORMATION_TYPE, event, service_name, text, 0);\r
+\r
+  if (event == NSSM_EVENT_SERVICE_CONTROL_UNKNOWN) {\r
+    HeapFree(GetProcessHeap(), 0, text);\r
+  }\r
+}\r
+\r
 /* Service control handler */\r
 unsigned long WINAPI service_control_handler(unsigned long control, unsigned long event, void *data, void *context) {\r
   switch (control) {\r
     case SERVICE_CONTROL_SHUTDOWN:\r
     case SERVICE_CONTROL_STOP:\r
-      stop_service(0);\r
+      log_service_control(service_name, control, true);\r
+      stop_service(0, true, true);\r
+      return NO_ERROR;\r
+\r
+    case SERVICE_CONTROL_CONTINUE:\r
+      log_service_control(service_name, control, true);\r
+      if (! throttle_timer) return ERROR_CALL_NOT_IMPLEMENTED;\r
+      throttle = 0;\r
+      ZeroMemory(&throttle_duetime, sizeof(throttle_duetime));\r
+      SetWaitableTimer(throttle_timer, &throttle_duetime, 0, 0, 0, 0);\r
+      service_status.dwCurrentState = SERVICE_CONTINUE_PENDING;\r
+      service_status.dwWaitHint = throttle_milliseconds() + NSSM_WAITHINT_MARGIN;\r
+      log_event(EVENTLOG_INFORMATION_TYPE, NSSM_EVENT_RESET_THROTTLE, service_name, 0);\r
+      SetServiceStatus(service_handle, &service_status);\r
       return NO_ERROR;\r
+\r
+    case SERVICE_CONTROL_PAUSE:\r
+      /*\r
+        We don't accept pause messages but it isn't possible to register\r
+        only for continue messages so we have to handle this case.\r
+      */\r
+      log_service_control(service_name, control, false);\r
+      return ERROR_CALL_NOT_IMPLEMENTED;\r
   }\r
 \r
   /* Unknown control */\r
+  log_service_control(service_name, control, false);\r
   return ERROR_CALL_NOT_IMPLEMENTED;\r
 }\r
 \r
 /* Start the service */\r
 int start_service() {\r
-  if (pid) return 0;\r
+  stopping = false;\r
+\r
+  if (process_handle) return 0;\r
 \r
   /* Allocate a STARTUPINFO structure for a new process */\r
   STARTUPINFO si;\r
@@ -207,70 +346,178 @@ int start_service() {
   PROCESS_INFORMATION pi;\r
   ZeroMemory(&pi, sizeof(pi));\r
 \r
+  /* Get startup parameters */\r
+  char *env = 0;\r
+  int ret = get_parameters(service_name, exe, sizeof(exe), flags, sizeof(flags), dir, sizeof(dir), &env, &throttle_delay);\r
+  if (ret) {\r
+    log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_GET_PARAMETERS_FAILED, service_name, 0);\r
+    return stop_service(2, true, true);\r
+  }\r
+\r
   /* Launch executable with arguments */\r
-  char cmd[MAX_PATH];\r
-  if (_snprintf(cmd, sizeof(cmd), "%s %s", exe, flags) < 0) {\r
-    eventprintf(EVENTLOG_ERROR_TYPE, "Error constructing command line");\r
-    return stop_service(2);\r
+  char cmd[CMD_LENGTH];\r
+  if (_snprintf(cmd, sizeof(cmd), "\"%s\" %s", exe, flags) < 0) {\r
+    log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_OUT_OF_MEMORY, "command line", "start_service", 0);\r
+    return stop_service(2, true, true);\r
   }\r
-  if (! CreateProcess(0, cmd, 0, 0, 0, 0, 0, dir, &si, &pi)) {\r
-    eventprintf(EVENTLOG_ERROR_TYPE, "Can't launch %s.  CreateProcess() returned %s", exe, error_string(GetLastError()));\r
-    return stop_service(3);\r
+\r
+  throttle_restart();\r
+\r
+  if (! CreateProcess(0, cmd, 0, 0, false, 0, env, dir, &si, &pi)) {\r
+    unsigned long error = GetLastError();\r
+    if (error == ERROR_INVALID_PARAMETER && env) log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_CREATEPROCESS_FAILED_INVALID_ENVIRONMENT, service_name, exe, NSSM_REG_ENV, 0);\r
+    else log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_CREATEPROCESS_FAILED, service_name, exe, error_string(error), 0);\r
+    return stop_service(3, true, true);\r
   }\r
-  pid = pi.hProcess;\r
+  process_handle = pi.hProcess;\r
+  pid = pi.dwProcessId;\r
 \r
   /* Signal successful start */\r
   service_status.dwCurrentState = SERVICE_RUNNING;\r
   SetServiceStatus(service_handle, &service_status);\r
 \r
+  /* Wait for a clean startup. */\r
+  if (WaitForSingleObject(process_handle, throttle_delay) == WAIT_TIMEOUT) throttle = 0;\r
+\r
   return 0;\r
 }\r
 \r
 /* Stop the service */\r
-int stop_service(unsigned long exitcode) {\r
+int stop_service(unsigned long exitcode, bool graceful, bool default_action) {\r
+  if (default_action && ! exitcode && ! graceful) {\r
+    log_event(EVENTLOG_INFORMATION_TYPE, NSSM_EVENT_GRACEFUL_SUICIDE, service_name, exe, exit_action_strings[NSSM_EXIT_UNCLEAN], exit_action_strings[NSSM_EXIT_UNCLEAN], exit_action_strings[NSSM_EXIT_UNCLEAN], exit_action_strings[NSSM_EXIT_REALLY] ,0);\r
+    graceful = true;\r
+  }\r
+\r
   /* Signal we are stopping */\r
-  service_status.dwCurrentState = SERVICE_STOP_PENDING;\r
-  SetServiceStatus(service_handle, &service_status);\r
+  if (graceful) {\r
+    service_status.dwCurrentState = SERVICE_STOP_PENDING;\r
+    service_status.dwWaitHint = NSSM_KILL_WINDOW_GRACE_PERIOD + NSSM_KILL_THREADS_GRACE_PERIOD + NSSM_WAITHINT_MARGIN;\r
+    SetServiceStatus(service_handle, &service_status);\r
+  }\r
 \r
   /* Nothing to do if server isn't running */\r
   if (pid) {\r
     /* Shut down server */\r
-    TerminateProcess(pid, 0);\r
-    pid = 0;\r
+    log_event(EVENTLOG_INFORMATION_TYPE, NSSM_EVENT_TERMINATEPROCESS, service_name, exe, 0);\r
+    kill_process(service_name, process_handle, pid, 0);\r
+    process_handle = 0;\r
   }\r
+  else log_event(EVENTLOG_INFORMATION_TYPE, NSSM_EVENT_PROCESS_ALREADY_STOPPED, service_name, exe, 0);\r
+\r
+  end_service((void *) pid, true);\r
 \r
   /* Signal we stopped */\r
-  service_status.dwCurrentState = SERVICE_STOPPED;\r
-  if (exitcode) {\r
-    service_status.dwWin32ExitCode = ERROR_SERVICE_SPECIFIC_ERROR;\r
-    service_status.dwServiceSpecificExitCode = exitcode;\r
-  }\r
-  else {\r
-    service_status.dwWin32ExitCode = NO_ERROR;\r
-    service_status.dwServiceSpecificExitCode = 0;\r
+  if (graceful) {\r
+    service_status.dwCurrentState = SERVICE_STOPPED;\r
+    if (exitcode) {\r
+      service_status.dwWin32ExitCode = ERROR_SERVICE_SPECIFIC_ERROR;\r
+      service_status.dwServiceSpecificExitCode = exitcode;\r
+    }\r
+    else {\r
+      service_status.dwWin32ExitCode = NO_ERROR;\r
+      service_status.dwServiceSpecificExitCode = 0;\r
+    }\r
+    SetServiceStatus(service_handle, &service_status);\r
   }\r
-  SetServiceStatus(service_handle, &service_status);\r
 \r
   return exitcode;\r
 }\r
 \r
 /* Callback function triggered when the server exits */\r
 void CALLBACK end_service(void *arg, unsigned char why) {\r
-  /* Check exit code */\r
-  unsigned long ret = 0;\r
-  GetExitCodeProcess(pid, &ret);\r
+  if (stopping) return;\r
+\r
+  stopping = true;\r
 \r
-  /* Force an error code if none given, so system can restart this service */\r
-  /*if (! ret) {\r
-    eventprintf(EVENTLOG_INFORMATION_TYPE, "Process exited with return code 0 - overriding with return code 111 so the service manager will notice the failure");\r
-    ret = 111;\r
+  pid = (unsigned long) arg;\r
+\r
+  /* Check exit code */\r
+  unsigned long exitcode = 0;\r
+  GetExitCodeProcess(process_handle, &exitcode);\r
+\r
+  /* Clean up. */\r
+  kill_process_tree(service_name, pid, exitcode, pid);\r
+\r
+  /*\r
+    The why argument is true if our wait timed out or false otherwise.\r
+    Our wait is infinite so why will never be true when called by the system.\r
+    If it is indeed true, assume we were called from stop_service() because\r
+    this is a controlled shutdown, and don't take any restart action.\r
+  */\r
+  if (why) return;\r
+\r
+  char code[16];\r
+  _snprintf(code, sizeof(code), "%d", exitcode);\r
+  log_event(EVENTLOG_INFORMATION_TYPE, NSSM_EVENT_ENDED_SERVICE, exe, service_name, code, 0);\r
+\r
+  /* What action should we take? */\r
+  int action = NSSM_EXIT_RESTART;\r
+  unsigned char action_string[ACTION_LEN];\r
+  bool default_action;\r
+  if (! get_exit_action(service_name, &exitcode, action_string, &default_action)) {\r
+    for (int i = 0; exit_action_strings[i]; i++) {\r
+      if (! _strnicmp((const char *) action_string, exit_action_strings[i], ACTION_LEN)) {\r
+        action = i;\r
+        break;\r
+      }\r
+    }\r
   }\r
-  else */eventprintf(EVENTLOG_INFORMATION_TYPE, "Process %s exited with return code %u", exe, ret);\r
 \r
-  /* Try to restart the service or return failure code to service manager */\r
+  process_handle = 0;\r
   pid = 0;\r
-  while (monitor_service()) {\r
-    eventprintf(EVENTLOG_INFORMATION_TYPE, "Failed to restart %s - sleeping ", exe, ret);\r
-    Sleep(30000);\r
+  switch (action) {\r
+    /* Try to restart the service or return failure code to service manager */\r
+    case NSSM_EXIT_RESTART:\r
+      log_event(EVENTLOG_INFORMATION_TYPE, NSSM_EVENT_EXIT_RESTART, service_name, code, exit_action_strings[action], exe, 0);\r
+      while (monitor_service()) {\r
+        log_event(EVENTLOG_WARNING_TYPE, NSSM_EVENT_RESTART_SERVICE_FAILED, exe, service_name, 0);\r
+        Sleep(30000);\r
+      }\r
+    break;\r
+\r
+    /* Do nothing, just like srvany would */\r
+    case NSSM_EXIT_IGNORE:\r
+      log_event(EVENTLOG_INFORMATION_TYPE, NSSM_EVENT_EXIT_IGNORE, service_name, code, exit_action_strings[action], exe, 0);\r
+      Sleep(INFINITE);\r
+    break;\r
+\r
+    /* Tell the service manager we are finished */\r
+    case NSSM_EXIT_REALLY:\r
+      log_event(EVENTLOG_INFORMATION_TYPE, NSSM_EVENT_EXIT_REALLY, service_name, code, exit_action_strings[action], 0);\r
+      stop_service(exitcode, true, default_action);\r
+    break;\r
+\r
+    /* Fake a crash so pre-Vista service managers will run recovery actions. */\r
+    case NSSM_EXIT_UNCLEAN:\r
+      log_event(EVENTLOG_INFORMATION_TYPE, NSSM_EVENT_EXIT_UNCLEAN, service_name, code, exit_action_strings[action], 0);\r
+      exit(stop_service(exitcode, false, default_action));\r
+    break;\r
   }\r
 }\r
+\r
+void throttle_restart() {\r
+  /* This can't be a restart if the service is already running. */\r
+  if (! throttle++) return;\r
+\r
+  int ms = throttle_milliseconds();\r
+\r
+  if (throttle > 7) throttle = 8;\r
+\r
+  char threshold[8], milliseconds[8];\r
+  _snprintf(threshold, sizeof(threshold), "%d", throttle_delay);\r
+  _snprintf(milliseconds, sizeof(milliseconds), "%d", ms);\r
+  log_event(EVENTLOG_WARNING_TYPE, NSSM_EVENT_THROTTLED, service_name, threshold, milliseconds, 0);\r
+\r
+  if (throttle_timer) {\r
+    ZeroMemory(&throttle_duetime, sizeof(throttle_duetime));\r
+    throttle_duetime.QuadPart = 0 - (ms * 10000LL);\r
+    SetWaitableTimer(throttle_timer, &throttle_duetime, 0, 0, 0, 0);\r
+  }\r
+\r
+  service_status.dwCurrentState = SERVICE_PAUSED;\r
+  SetServiceStatus(service_handle, &service_status);\r
+\r
+  if (throttle_timer) WaitForSingleObject(throttle_timer, INFINITE);\r
+  else Sleep(ms);\r
+}\r