DC: Move dynamic plugin handling into the platform

2011-04-20 22:30:01 +02:00 · 2011-04-20 22:30:01 +02:00 · 21421d2e86
commit 21421d2e86
parent eb8b1a962b
7 changed files with 24 additions and 58 deletions
--- a/backends/platform/dc/plugins.cpp
+++ b/backends/platform/dc/plugins.cpp
@ -0,0 +1,100 @@
+/* ScummVM - Graphic Adventure Engine
+ *
+ * ScummVM is the legal property of its developers, whose names
+ * are too numerous to list here. Please refer to the COPYRIGHT
+ * file distributed with this source distribution.
+ *
+ * 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * $URL$
+ * $Id$
+ *
+ */
+
+#include "common/scummsys.h"
+
+#if defined(DYNAMIC_MODULES)
+
+#include "backends/plugins/dynamic-plugin.h"
+#include "common/fs.h"
+
+#include "dcloader.h"
+
+
+class OSystem_Dreamcast::DCPlugin : public DynamicPlugin {
+protected:
+	void *_dlHandle;
+
+	virtual VoidFunc findSymbol(const char *symbol) {
+		void *func = dlsym(_dlHandle, symbol);
+		if (!func)
+			warning("Failed loading symbol '%s' from plugin '%s' (%s)", symbol, _filename.c_str(), dlerror());
+
+		// FIXME HACK: This is a HACK to circumvent a clash between the ISO C++
+		// standard and POSIX: ISO C++ disallows casting between function pointers
+		// and data pointers, but dlsym always returns a void pointer. For details,
+		// see e.g. <http://www.trilithium.com/johan/2004/12/problem-with-dlsym/>.
+		assert(sizeof(VoidFunc) == sizeof(func));
+		VoidFunc tmp;
+		memcpy(&tmp, &func, sizeof(VoidFunc));
+		return tmp;
+	}
+
+public:
+	DCPlugin(const Common::String &filename)
+		: DynamicPlugin(filename), _dlHandle(0) {}
+
+	bool loadPlugin() {
+		assert(!_dlHandle);
+		_dlHandle = dlopen(_filename.c_str(), RTLD_LAZY);
+
+		if (!_dlHandle) {
+			warning("Failed loading plugin '%s' (%s)", _filename.c_str(), dlerror());
+			return false;
+		}
+
+		bool ret = DynamicPlugin::loadPlugin();
+
+		if (ret)
+			dlforgetsyms(_dlHandle);
+
+		return ret;
+	}
+
+	void unloadPlugin() {
+		DynamicPlugin::unloadPlugin();
+		if (_dlHandle) {
+			if (dlclose(_dlHandle) != 0)
+				warning("Failed unloading plugin '%s' (%s)", _filename.c_str(), dlerror());
+			_dlHandle = 0;
+		}
+	}
+};
+
+
+Plugin* OSystem_Dreamcast::createPlugin(const Common::FSNode &node) const {
+	return new DCPlugin(node.getPath());
+}
+
+bool OSystem_Dreamcast::isPluginFilename(const Common::FSNode &node) const {
+	// Check the plugin suffix
+	Common::String filename = node.getName();
+	if (!filename.hasSuffix(".PLG"))
+		return false;
+
+	return true;
+}
+
+#endif // defined(DYNAMIC_MODULES)