Added await_shutdown() function.

[nssm.git] / service.cpp

diff --git a/service.cpp b/service.cpp
index f14390f..028b035 100644 (file)
--- a/service.cpp
+++ b/service.cpp
@@ -599,3 +599,89 @@ void throttle_restart() {
     else Sleep(ms);\r
   }\r
 }\r
+\r
+/*\r
+  When responding to a stop (or any other) request we need to set dwWaitHint to\r
+  the number of milliseconds we expect the operation to take, and optionally\r
+  increase dwCheckPoint.  If dwWaitHint milliseconds elapses without the\r
+  operation completing or dwCheckPoint increasing, the system will consider the\r
+  service to be hung.\r
+\r
+  However the system will consider the service to be hung after 30000\r
+  milliseconds regardless of the value of dwWaitHint if dwCheckPoint has not\r
+  changed.  Therefore if we want to wait longer than that we must periodically\r
+  increase dwCheckPoint.\r
+\r
+  Furthermore, it will consider the service to be hung after 60000 milliseconds\r
+  regardless of the value of dwCheckPoint unless dwWaitHint is increased every\r
+  time dwCheckPoint is also increased.\r
+\r
+  Our strategy then is to retrieve the initial dwWaitHint and wait for\r
+  NSSM_SHUTDOWN_CHECKPOINT milliseconds.  If the process is still running and\r
+  we haven't finished waiting we increment dwCheckPoint and add whichever is\r
+  smaller of NSSM_SHUTDOWN_CHECKPOINT or the remaining timeout to dwWaitHint.\r
+\r
+  Only doing both these things will prevent the system from killing the service.\r
+\r
+  Returns: 1 if the wait timed out.\r
+           0 if the wait completed.\r
+          -1 on error.\r
+*/\r
+int await_shutdown(char *function_name, char *service_name, SERVICE_STATUS_HANDLE service_handle, SERVICE_STATUS *service_status, HANDLE process_handle, unsigned long timeout) {\r
+  unsigned long interval;\r
+  unsigned long waithint;\r
+  unsigned long ret;\r
+  unsigned long waited;\r
+  char interval_milliseconds[16];\r
+  char timeout_milliseconds[16];\r
+  char waited_milliseconds[16];\r
+  char *function = function_name;\r
+\r
+  /* Add brackets to function name. */\r
+  size_t funclen = strlen(function_name) + 3;\r
+  char *func = (char *) HeapAlloc(GetProcessHeap(), 0, funclen);\r
+  if (func) {\r
+    if (_snprintf_s(func, funclen, _TRUNCATE, "%s()", function_name) > -1) function = func;\r
+  }\r
+\r
+  _snprintf_s(timeout_milliseconds, sizeof(timeout_milliseconds), _TRUNCATE, "%lu", timeout);\r
+\r
+  waithint = service_status->dwWaitHint;\r
+  waited = 0;\r
+  while (waited < timeout) {\r
+    interval = timeout - waited;\r
+    if (interval > NSSM_SHUTDOWN_CHECKPOINT) interval = NSSM_SHUTDOWN_CHECKPOINT;\r
+\r
+    service_status->dwCurrentState = SERVICE_STOP_PENDING;\r
+    service_status->dwWaitHint += interval;\r
+    service_status->dwCheckPoint++;\r
+    SetServiceStatus(service_handle, service_status);\r
+\r
+    if (waited) {\r
+      _snprintf_s(waited_milliseconds, sizeof(waited_milliseconds), _TRUNCATE, "%lu", waited);\r
+      _snprintf_s(interval_milliseconds, sizeof(interval_milliseconds), _TRUNCATE, "%lu", interval);\r
+      log_event(EVENTLOG_INFORMATION_TYPE, NSSM_EVENT_AWAITING_SHUTDOWN, function, service_name, waited_milliseconds, interval_milliseconds, timeout_milliseconds, 0);\r
+    }\r
+\r
+    switch (WaitForSingleObject(process_handle, interval)) {\r
+      case WAIT_OBJECT_0:\r
+        ret = 0;\r
+        goto awaited;\r
+\r
+      case WAIT_TIMEOUT:\r
+        ret = 1;\r
+      break;\r
+\r
+      default:\r
+        ret = -1;\r
+        goto awaited;\r
+    }\r
+\r
+    waited += interval;\r
+  }\r
+\r
+awaited:\r
+  if (func) HeapFree(GetProcessHeap(), 0, func);\r
+\r
+  return ret;\r
+}\r