added code for loading dynamic plugins(DLLs) for windows

svn-id: r18356

3 files changed, 50 insertions, 5 deletions

diff --git a/base/plugins.cpp b/base/plugins.cpp
index 695ed6ede6..1dbcf4609f 100644
--- a/base/plugins.cpp
+++ b/base/plugins.cpp
@@ -47,9 +47,15 @@ typedef DetectedGameList (*DetectFunc)(const FSList &fslist);
 #define PLUGIN_PREFIX		""
 #define PLUGIN_SUFFIX		".plg"
 #else
+#ifdef _WIN32
+#define PLUGIN_DIRECTORY	""
+#define PLUGIN_PREFIX		""
+#define PLUGIN_SUFFIX		".dll"
+#else
 #error No support for loading plugins on non-unix systems at this point!
 #endif
 #endif
+#endif
 
 #else
 
@@ -138,24 +144,44 @@ public:
 };
 
 void *DynamicPlugin::findSymbol(const char *symbol) {
-#if defined(UNIX)||defined(__DC__)
+#if defined(UNIX) || defined(__DC__)
 	void *func = dlsym(_dlHandle, symbol);
 	if (!func)
 		warning("Failed loading symbol '%s' from plugin '%s' (%s)", symbol, _filename.c_str(), dlerror());
 	return func;
 #else
+#if defined(_WIN32)
+	void *func = GetProcAddress((HMODULE)_dlHandle, symbol);
+	if (!func)
+		warning("Failed loading symbol '%s' from plugin '%s'", symbol, _filename.c_str());
+	return func;
+#else
 #error TODO
 #endif
+#endif
 }
 
 bool DynamicPlugin::loadPlugin() {
 	assert(!_dlHandle);
+#if defined(UNIX) || defined(__DC__)
 	_dlHandle = dlopen(_filename.c_str(), RTLD_LAZY);
 
 	if (!_dlHandle) {
 		warning("Failed loading plugin '%s' (%s)", _filename.c_str(), dlerror());
 		return false;
 	}
+#else
+#if defined(_WIN32)
+	_dlHandle = LoadLibrary(_filename.c_str());
+
+	if (!_dlHandle) {
+		warning("Failed loading plugin '%s'", _filename.c_str());
+		return false;
+	}
+#else
+#error TODO
+#endif
+#endif
 
 	// Query the plugin's name
 	NameFunc nameFunc = (NameFunc)findSymbol("PLUGIN_name");
@@ -195,11 +221,23 @@ bool DynamicPlugin::loadPlugin() {
 }
 
 void DynamicPlugin::unloadPlugin() {
+#if defined(UNIX) || defined(__DC__)
 	if (_dlHandle) {
 		if (dlclose(_dlHandle) != 0)
 			warning("Failed unloading plugin '%s' (%s)", _filename.c_str(), dlerror());
 	}
 }
+#else
+#if defined(_WIN32)
+	if (_dlHandle) {
+		if (!FreeLibrary((HMODULE)_dlHandle))
+			warning("Failed unloading plugin '%s'", _filename.c_str());
+	}
+}
+#else
+#error TODO
+#endif
+#endif
 
 #endif	// DYNAMIC_MODULES
 
diff --git a/base/plugins.h b/base/plugins.h
index f9a5567834..11eb4a3e3f 100644
--- a/base/plugins.h
+++ b/base/plugins.h
@@ -92,10 +92,10 @@ public:
 #else
 #define REGISTER_PLUGIN(ID,name) \
 	extern "C" { \
-		const char *PLUGIN_name() { return name; } \
-		GameList PLUGIN_getSupportedGames() { return Engine_##ID##_gameList(); } \
-		Engine *PLUGIN_createEngine(GameDetector *detector, OSystem *syst) { return Engine_##ID##_create(detector, syst); } \
-		DetectedGameList PLUGIN_detectGames(const FSList &fslist) { return Engine_##ID##_detectGames(fslist); } \
+		PLUGIN_EXPORT const char *PLUGIN_name() { return name; } \
+		PLUGIN_EXPORT GameList PLUGIN_getSupportedGames() { return Engine_##ID##_gameList(); } \
+		PLUGIN_EXPORT Engine *PLUGIN_createEngine(GameDetector *detector, OSystem *syst) { return Engine_##ID##_create(detector, syst); } \
+		PLUGIN_EXPORT DetectedGameList PLUGIN_detectGames(const FSList &fslist) { return Engine_##ID##_detectGames(fslist); } \
 	}
 #endif
 
diff --git a/common/scummsys.h b/common/scummsys.h
index 60972da38c..a0ba3622c1 100644
--- a/common/scummsys.h
+++ b/common/scummsys.h
@@ -53,6 +53,7 @@
 
 	#define FORCEINLINE __forceinline
 	#define NORETURN _declspec(noreturn)
+	#define PLUGIN_EXPORT __declspec(dllexport)
 
 	typedef unsigned char byte;
 	typedef unsigned char uint8;
@@ -92,6 +93,8 @@
 	#define START_PACK_STRUCTS pack (push, 1)
 	#define END_PACK_STRUCTS	 pack(pop)
 
+	#define PLUGIN_EXPORT __declspec(dllexport)
+
 #elif defined(UNIX)
 
 	#define scumm_stricmp strcasecmp
@@ -322,6 +325,10 @@
 #define	CDECL
 #endif
 
+#ifndef PLUGIN_EXPORT
+#define PLUGIN_EXPORT
+#endif
+
 #ifndef NORETURN
 #define	NORETURN
 #endif