src: use RAII for mutexes in node_watchdog.cc

PR-URL: #7933 Reviewed-By: James M Snell <jasnell@gmail.com> Reviewed-By: Colin Ihrig <cjihrig@gmail.com>

Author: addaleax

src/node_watchdog.cc

@@ -160,7 +160,7 @@ BOOL WINAPI SigintWatchdogHelper::WinCtrlCHandlerRoutine(DWORD dwCtrlType) {
 
 
 bool SigintWatchdogHelper::InformWatchdogsAboutSignal() {
- uv_mutex_lock(&instance.list_mutex_);
+ Mutex::ScopedLock list_lock(instance.list_mutex_);
 
  bool is_stopping = false;
 #ifdef __POSIX__
@@ -176,17 +176,15 @@ bool SigintWatchdogHelper::InformWatchdogsAboutSignal() {
  for (auto it : instance.watchdogs_)
  it->HandleSigint();
 
- uv_mutex_unlock(&instance.list_mutex_);
  return is_stopping;
 }
 
 
 int SigintWatchdogHelper::Start() {
- int ret = 0;
- uv_mutex_lock(&mutex_);
+ Mutex::ScopedLock lock(mutex_);
 
  if (start_stop_count_++ > 0) {
- goto dont_start;
+ return 0;
  }
 
 #ifdef __POSIX__
@@ -197,10 +195,10 @@ int SigintWatchdogHelper::Start() {
  sigset_t sigmask;
  sigfillset(&sigmask);
  CHECK_EQ(0, pthread_sigmask(SIG_SETMASK, &sigmask, &sigmask));
- ret = pthread_create(&thread_, nullptr, RunSigintWatchdog, nullptr);
+ int ret = pthread_create(&thread_, nullptr, RunSigintWatchdog, nullptr);
  CHECK_EQ(0, pthread_sigmask(SIG_SETMASK, &sigmask, nullptr));
  if (ret != 0) {
- goto dont_start;
+ return ret;
  }
  has_running_thread_ = true;
 
@@ -209,34 +207,36 @@ int SigintWatchdogHelper::Start() {
  SetConsoleCtrlHandler(WinCtrlCHandlerRoutine, TRUE);
 #endif
 
- dont_start:
- uv_mutex_unlock(&mutex_);
- return ret;
+ return 0;
 }
 
 
 bool SigintWatchdogHelper::Stop() {
- uv_mutex_lock(&mutex_);
- uv_mutex_lock(&list_mutex_);
+ bool had_pending_signal;
+ Mutex::ScopedLock lock(mutex_);
 
- bool had_pending_signal = has_pending_signal_;
+ {
+ Mutex::ScopedLock list_lock(list_mutex_);
 
- if (--start_stop_count_ > 0) {
- uv_mutex_unlock(&list_mutex_);
- goto dont_stop;
- }
+ had_pending_signal = has_pending_signal_;
+
+ if (--start_stop_count_ > 0) {
+ has_pending_signal_ = false;
+ return had_pending_signal;
+ }
 
 #ifdef __POSIX__
- // Set stopping now because it's only protected by list_mutex_.
- stopping_ = true;
+  // Set stopping now because it's only protected by list_mutex_.
+  stopping_ = true;
 #endif
 
- watchdogs_.clear();
- uv_mutex_unlock(&list_mutex_);
+  watchdogs_.clear();
+ }
 
 #ifdef __POSIX__
  if (!has_running_thread_) {
- goto dont_stop;
+ has_pending_signal_ = false;
+ return had_pending_signal;
  }
 
  // Wake up the helper thread.
@@ -252,32 +252,26 @@ bool SigintWatchdogHelper::Stop() {
 #endif
 
  had_pending_signal = has_pending_signal_;
- dont_stop:
- uv_mutex_unlock(&mutex_);
-
  has_pending_signal_ = false;
+
  return had_pending_signal;
 }
 
 
 void SigintWatchdogHelper::Register(SigintWatchdog* wd) {
- uv_mutex_lock(&list_mutex_);
+ Mutex::ScopedLock lock(list_mutex_);
 
  watchdogs_.push_back(wd);
-
- uv_mutex_unlock(&list_mutex_);
 }
 
 
 void SigintWatchdogHelper::Unregister(SigintWatchdog* wd) {
- uv_mutex_lock(&list_mutex_);
+ Mutex::ScopedLock lock(list_mutex_);
 
  auto it = std::find(watchdogs_.begin(), watchdogs_.end(), wd);
 
  CHECK_NE(it, watchdogs_.end());
  watchdogs_.erase(it);
-
- uv_mutex_unlock(&list_mutex_);
 }
 
 
@@ -289,9 +283,6 @@ SigintWatchdogHelper::SigintWatchdogHelper()
  stopping_ = false;
  CHECK_EQ(0, uv_sem_init(&sem_, 0));
 #endif
-
- CHECK_EQ(0, uv_mutex_init(&mutex_));
- CHECK_EQ(0, uv_mutex_init(&list_mutex_));
 }
 
 
@@ -303,9 +294,6 @@ SigintWatchdogHelper::~SigintWatchdogHelper() {
  CHECK_EQ(has_running_thread_, false);
  uv_sem_destroy(&sem_);
 #endif
-
- uv_mutex_destroy(&mutex_);
- uv_mutex_destroy(&list_mutex_);
 }
 
 SigintWatchdogHelper SigintWatchdogHelper::instance;

src/node_watchdog.h

@@ -5,6 +5,7 @@
 
 #include "v8.h"
 #include "uv.h"
+#include "node_mutex.h"
 #include <vector>
 
 #ifdef __POSIX__
@@ -75,8 +76,8 @@ class SigintWatchdogHelper {
 
  int start_stop_count_;
 
- uv_mutex_t mutex_;
- uv_mutex_t list_mutex_;
+ Mutex mutex_;
+ Mutex list_mutex_;
  std::vector<SigintWatchdog*> watchdogs_;
  bool has_pending_signal_;