Throttle restarts.

[nssm.git] / service.cpp

diff --git a/service.cpp b/service.cpp
index 8e56cf7..1010666 100644 (file)
--- a/service.cpp
+++ b/service.cpp
@@ -10,10 +10,20 @@ char exe[EXE_LENGTH];
 char flags[CMD_LENGTH];\r
 char dir[MAX_PATH];\r
 bool stopping;\r
+CRITICAL_SECTION throttle_section;\r
+CONDITION_VARIABLE throttle_condition;\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
@@ -148,11 +158,11 @@ void WINAPI service_main(unsigned long argc, char **argv) {
   /* Initialise status */\r
   ZeroMemory(&service_status, sizeof(service_status));\r
   service_status.dwServiceType = SERVICE_WIN32_OWN_PROCESS | SERVICE_INTERACTIVE_PROCESS;\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
@@ -177,6 +187,7 @@ void WINAPI service_main(unsigned long argc, char **argv) {
   }\r
 \r
   service_status.dwCurrentState = SERVICE_START_PENDING;\r
+  service_status.dwWaitHint = NSSM_RESET_THROTTLE_RESTART + 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
@@ -184,6 +195,9 @@ void WINAPI service_main(unsigned long argc, char **argv) {
 \r
   set_service_recovery(service_name);\r
 \r
+  /* Used for signalling a resume if the service pauses when throttled. */\r
+  InitializeCriticalSection(&throttle_section);\r
+\r
   monitor_service();\r
 }\r
 \r
@@ -230,6 +244,22 @@ unsigned long WINAPI service_control_handler(unsigned long control, unsigned lon
     case SERVICE_CONTROL_STOP:\r
       stop_service(0, true, true);\r
       return NO_ERROR;\r
+\r
+    case SERVICE_CONTROL_CONTINUE:\r
+      throttle = 0;\r
+      WakeConditionVariable(&throttle_condition);\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
+      return ERROR_CALL_NOT_IMPLEMENTED;\r
   }\r
 \r
   /* Unknown control */\r
@@ -257,6 +287,9 @@ int start_service() {
     log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_OUT_OF_MEMORY, "command line", "start_service", 0);\r
     return stop_service(2, true, true);\r
   }\r
+\r
+  throttle_restart();\r
+\r
   if (! CreateProcess(0, cmd, 0, 0, false, 0, 0, dir, &si, &pi)) {\r
     log_event(EVENTLOG_ERROR_TYPE, NSSM_EVENT_CREATEPROCESS_FAILED, service_name, exe, GetLastError(), 0);\r
     return stop_service(3, true, true);\r
@@ -268,6 +301,9 @@ int start_service() {
   service_status.dwCurrentState = SERVICE_RUNNING;\r
   SetServiceStatus(service_handle, &service_status);\r
 \r
+  /* Wait for a clean startup. */\r
+  if (WaitForSingleObject(process_handle, NSSM_RESET_THROTTLE_RESTART) == WAIT_TIMEOUT) throttle = 0;\r
+\r
   return 0;\r
 }\r
 \r
@@ -281,6 +317,7 @@ int stop_service(unsigned long exitcode, bool graceful, bool default_action) {
   /* Signal we are stopping */\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
@@ -383,3 +420,26 @@ void CALLBACK end_service(void *arg, unsigned char why) {
     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", NSSM_RESET_THROTTLE_RESTART);\r
+  _snprintf(milliseconds, sizeof(milliseconds), "%d", ms);\r
+  log_event(EVENTLOG_WARNING_TYPE, NSSM_EVENT_THROTTLED, service_name, threshold, milliseconds, 0);\r
+\r
+  EnterCriticalSection(&throttle_section);\r
+\r
+  service_status.dwCurrentState = SERVICE_PAUSED;\r
+  SetServiceStatus(service_handle, &service_status);\r
+\r
+  SleepConditionVariableCS(&throttle_condition, &throttle_section, ms);\r
+\r
+  LeaveCriticalSection(&throttle_section);\r
+}\r