Added a convenience class 'Mutex'

svn-id: r16566

common/module.mk

@@ -4,6 +4,7 @@ MODULE_OBJS := \
 	common/config-manager.o \
 	common/file.o \
 	common/md5.o \
+	common/mutex.o \
 	common/str.o \
 	common/stream.o \
 	common/timer.o \

common/mutex.cpp

@@ -0,0 +1,76 @@
+/* ScummVM - Scumm Interpreter
+ * Copyright (C) 2003-2005 The ScummVM project
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+ *
+ * $Header$
+ *
+ */
+
+#include "stdafx.h"
+#include "common/mutex.h"
+#include "common/system.h"
+
+namespace Common {
+
+Mutex::Mutex() {
+	_mutex = g_system->createMutex();
+}
+
+Mutex::~Mutex() {
+	g_system->deleteMutex(_mutex);
+}
+
+void Mutex::lock() {
+	g_system->lockMutex(_mutex);
+}
+
+void Mutex::unlock() {
+	g_system->unlockMutex(_mutex);
+}
+
+
+#pragma mark -
+
+
+StackLock::StackLock(OSystem::MutexRef mutex, const char *mutexName)
+	: _mutex(mutex), _mutexName(mutexName) {
+	lock();
+}
+
+StackLock::StackLock(const Mutex &mutex, const char *mutexName)
+	: _mutex(mutex._mutex), _mutexName(mutexName) {
+	lock();
+}
+
+StackLock::~StackLock() {
+	unlock();
+}
+
+void StackLock::lock() {
+	if (_mutexName != NULL)
+		debug(6, "Locking mutex %s", _mutexName);
+	
+	g_system->lockMutex(_mutex);
+}
+
+void StackLock::unlock() {
+	if (_mutexName != NULL)
+		debug(6, "Unlocking mutex %s", _mutexName);
+
+	g_system->unlockMutex(_mutex);
+}
+
+}	// End of namespace Common

common/mutex.h

@@ -26,10 +26,12 @@
 
 namespace Common {
 
+class Mutex;
+
 /**
  * An pseudo-opaque mutex type. See OSystem::createMutex etc. for more details.
  */
-typedef struct Mutex *MutexRef;
+typedef struct OpaqueMutex *MutexRef;
 
 
 /**
@@ -43,10 +45,28 @@ class StackLock {
 	void unlock();
 public:
 	StackLock(MutexRef mutex, const char *mutexName = NULL);
+	StackLock(const Mutex &mutex, const char *mutexName = NULL);
 	~StackLock();
 };
 
 
+/**
+ * Wrapper class around the OSystem mutex functions.
+ */
+class Mutex {
+	friend class StackLock;
+
+	MutexRef _mutex;
+
+public:
+	Mutex();
+	~Mutex();
+
+	void lock();
+	void unlock();
+};
+
+
 } // End of namespace Common
 
 #endif