From 9eaf2e9517af9ee3fa09c670c96e0f9ffa08282e Mon Sep 17 00:00:00 2001
From: Bartosz Sosnowski <bartosz@janeasystems.com>
Date: Mon, 12 Dec 2016 12:02:10 +0100
Subject: [PATCH] watchdog: add flag to mark handler as disabled

Adds flags that marks WinCtrlCHandlerRoutine as disabled instead of
removing it. Trying to remove the controller from the controller
handle itself leads to deadlock.

PR-URL: https://github.com/nodejs/node/pull/10248
Reviewed-By: Anna Henningsen <anna@addaleax.net>
---
 src/node_watchdog.cc | 13 ++++++++++---
 src/node_watchdog.h  |  1 +
 2 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/src/node_watchdog.cc b/src/node_watchdog.cc
index 01b39123be5e7c..5d95c4132f1b3f 100644
--- a/src/node_watchdog.cc
+++ b/src/node_watchdog.cc
@@ -150,7 +150,8 @@ void SigintWatchdogHelper::HandleSignal(int signum) {
 // Windows starts a separate thread for executing the handler, so no extra
 // helper thread is required.
 BOOL WINAPI SigintWatchdogHelper::WinCtrlCHandlerRoutine(DWORD dwCtrlType) {
-  if (dwCtrlType == CTRL_C_EVENT || dwCtrlType == CTRL_BREAK_EVENT) {
+  if (!instance.watchdog_disabled_ &&
+      (dwCtrlType == CTRL_C_EVENT || dwCtrlType == CTRL_BREAK_EVENT)) {
     InformWatchdogsAboutSignal();
 
     // Return true because the signal has been handled.
@@ -207,7 +208,11 @@ int SigintWatchdogHelper::Start() {
 
   RegisterSignalHandler(SIGINT, HandleSignal);
 #else
-  SetConsoleCtrlHandler(WinCtrlCHandlerRoutine, TRUE);
+  if (watchdog_disabled_) {
+    watchdog_disabled_ = false;
+  } else {
+    SetConsoleCtrlHandler(WinCtrlCHandlerRoutine, TRUE);
+  }
 #endif
 
   return 0;
@@ -251,7 +256,7 @@ bool SigintWatchdogHelper::Stop() {
 
   RegisterSignalHandler(SIGINT, SignalExit, true);
 #else
-  SetConsoleCtrlHandler(WinCtrlCHandlerRoutine, FALSE);
+  watchdog_disabled_ = true;
 #endif
 
   had_pending_signal = has_pending_signal_;
@@ -292,6 +297,8 @@ SigintWatchdogHelper::SigintWatchdogHelper()
   has_running_thread_ = false;
   stopping_ = false;
   CHECK_EQ(0, uv_sem_init(&sem_, 0));
+#else
+  watchdog_disabled_ = false;
 #endif
 }
 
diff --git a/src/node_watchdog.h b/src/node_watchdog.h
index dd97e4e735ccdf..2d55d782d0af5d 100644
--- a/src/node_watchdog.h
+++ b/src/node_watchdog.h
@@ -91,6 +91,7 @@ class SigintWatchdogHelper {
   static void* RunSigintWatchdog(void* arg);
   static void HandleSignal(int signum);
 #else
+  bool watchdog_disabled_;
   static BOOL WINAPI WinCtrlCHandlerRoutine(DWORD dwCtrlType);
 #endif
 };