base: extract mutex.h from logging.cpp.

Extract the Windows-specific mutex implementation from logging.cpp.

Bug: http://b/31468413
Change-Id: I0a895911ec6d815b8011b09d55209b64bbf9a70e
Test: mma

base/include/android-base/mutex.h

@@ -0,0 +1,49 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include <mutex>
+
+#include "android-base/macros.h"
+
+#if defined(_WIN32)
+#include <windows.h>
+
+namespace std {
+class mutex {
+ public:
+  mutex() {
+    InitializeCriticalSection(&critical_section_);
+  }
+  ~mutex() {
+    DeleteCriticalSection(&critical_section_);
+  }
+
+  void lock() {
+    EnterCriticalSection(&critical_section_);
+  }
+
+  void unlock() {
+    LeaveCriticalSection(&critical_section_);
+  }
+
+ private:
+  CRITICAL_SECTION critical_section_;
+  DISALLOW_COPY_AND_ASSIGN(mutex);
+};
+} // namespace std
+#endif

base/logging.cpp

@@ -37,16 +37,14 @@
 
 #include <iostream>
 #include <limits>
+#include <mutex>
 #include <sstream>
 #include <string>
 #include <utility>
 #include <vector>
 
-#ifndef _WIN32
-#include <mutex>
-#endif
-
 #include "android-base/macros.h"
+#include "android-base/mutex.h"
 #include "android-base/strings.h"
 
 // Headers for LogMessage::LogLine.
@@ -92,17 +90,11 @@ static thread_id GetThreadId() {
 }
 
 namespace {
-#ifndef _WIN32
-using std::mutex;
-using std::lock_guard;
-
 #if defined(__GLIBC__)
 const char* getprogname() {
   return program_invocation_short_name;
 }
-#endif
-
-#else
+#elif defined(_WIN32)
 const char* getprogname() {
   static bool first = true;
   static char progname[MAX_PATH] = {};
@@ -121,51 +113,13 @@ const char* getprogname() {
 
   return progname;
 }
-
-class mutex {
- public:
-  mutex() {
-    InitializeCriticalSection(&critical_section_);
-  }
-  ~mutex() {
-    DeleteCriticalSection(&critical_section_);
-  }
-
-  void lock() {
-    EnterCriticalSection(&critical_section_);
-  }
-
-  void unlock() {
-    LeaveCriticalSection(&critical_section_);
-  }
-
- private:
-  CRITICAL_SECTION critical_section_;
-};
-
-template <typename LockT>
-class lock_guard {
- public:
-  explicit lock_guard(LockT& lock) : lock_(lock) {
-    lock_.lock();
-  }
-
-  ~lock_guard() {
-    lock_.unlock();
-  }
-
- private:
-  LockT& lock_;
-
-  DISALLOW_COPY_AND_ASSIGN(lock_guard);
-};
 #endif
 } // namespace
 
 namespace android {
 namespace base {
 
-static auto& logging_lock = *new mutex();
+static auto& logging_lock = *new std::mutex();
 
 #ifdef __ANDROID__
 static auto& gLogger = *new LogFunction(LogdLogger());
@@ -354,12 +308,12 @@ void InitLogging(char* argv[], LogFunction&& logger, AbortFunction&& aborter) {
 }
 
 void SetLogger(LogFunction&& logger) {
-  lock_guard<mutex> lock(logging_lock);
+  std::lock_guard<std::mutex> lock(logging_lock);
   gLogger = std::move(logger);
 }
 
 void SetAborter(AbortFunction&& aborter) {
-  lock_guard<mutex> lock(logging_lock);
+  std::lock_guard<std::mutex> lock(logging_lock);
   gAborter = std::move(aborter);
 }
 
@@ -445,7 +399,7 @@ LogMessage::~LogMessage() {
 
   {
     // Do the actual logging with the lock held.
-    lock_guard<mutex> lock(logging_lock);
+    std::lock_guard<std::mutex> lock(logging_lock);
     if (msg.find('\n') == std::string::npos) {
       LogLine(data_->GetFile(), data_->GetLineNumber(), data_->GetId(),
               data_->GetSeverity(), msg.c_str());