Imported existing code

indra/llplugin/llplugininstance.cpp

@@ -0,0 +1,172 @@
+/** 
+ * @file llplugininstance.cpp
+ * @brief LLPluginInstance handles loading the dynamic library of a plugin and setting up its entry points for message passing.
+ *
+ * $LicenseInfo:firstyear=2008&license=viewergpl$
+ * 
+ * Copyright (c) 2008-2009, Linden Research, Inc.
+ * 
+ * Second Life Viewer Source Code
+ * The source code in this file ("Source Code") is provided by Linden Lab
+ * to you under the terms of the GNU General Public License, version 2.0
+ * ("GPL"), unless you have obtained a separate licensing agreement
+ * ("Other License"), formally executed by you and Linden Lab.  Terms of
+ * the GPL can be found in doc/GPL-license.txt in this distribution, or
+ * online at http://secondlifegrid.net/programs/open_source/licensing/gplv2
+ * 
+ * There are special exceptions to the terms and conditions of the GPL as
+ * it is applied to this Source Code. View the full text of the exception
+ * in the file doc/FLOSS-exception.txt in this software distribution, or
+ * online at
+ * http://secondlifegrid.net/programs/open_source/licensing/flossexception
+ * 
+ * By copying, modifying or distributing this software, you acknowledge
+ * that you have read and understood your obligations described above,
+ * and agree to abide by those obligations.
+ * 
+ * ALL LINDEN LAB SOURCE CODE IS PROVIDED "AS IS." LINDEN LAB MAKES NO
+ * WARRANTIES, EXPRESS, IMPLIED OR OTHERWISE, REGARDING ITS ACCURACY,
+ * COMPLETENESS OR PERFORMANCE.
+ * $/LicenseInfo$
+ */
+
+#include "linden_common.h"
+
+#include "llplugininstance.h"
+
+#include "llapr.h"
+
+/** Virtual destructor. */
+LLPluginInstanceMessageListener::~LLPluginInstanceMessageListener()
+{
+}
+
+/** 
+ * TODO:DOC describe how it's used
+ */
+const char *LLPluginInstance::PLUGIN_INIT_FUNCTION_NAME = "LLPluginInitEntryPoint";
+
+/** 
+ * Constructor.
+ *
+ * @param[in] owner Plugin instance. TODO:DOC is this a good description of what "owner" is?
+ */
+LLPluginInstance::LLPluginInstance(LLPluginInstanceMessageListener *owner) :
+	mDSOHandle(NULL),
+	mPluginUserData(NULL),
+	mPluginSendMessageFunction(NULL)
+{
+	mOwner = owner;
+}
+
+/** 
+ * Destructor.
+ */
+LLPluginInstance::~LLPluginInstance()
+{
+	if(mDSOHandle != NULL)
+	{
+		apr_dso_unload(mDSOHandle);
+		mDSOHandle = NULL;
+	}
+}
+
+/** 
+ * Dynamically loads the plugin and runs the plugin's init function.
+ *
+ * @param[in] plugin_file Name of plugin dll/dylib/so. TODO:DOC is this correct? see .h
+ * @return 0 if successful, APR error code or error code from the plugin's init function on failure.
+ */
+int LLPluginInstance::load(std::string &plugin_file)
+{
+	pluginInitFunction init_function = NULL;
+	
+	int result = apr_dso_load(&mDSOHandle,
+					  plugin_file.c_str(),
+					  gAPRPoolp);
+	if(result != APR_SUCCESS)
+	{
+		char buf[1024];
+		apr_dso_error(mDSOHandle, buf, sizeof(buf));
+
+		LL_WARNS("Plugin") << "apr_dso_load of " << plugin_file << " failed with error " << result << " , additional info string: " << buf << LL_ENDL;
+		
+	}
+	
+	if(result == APR_SUCCESS)
+	{
+		result = apr_dso_sym((apr_dso_handle_sym_t*)&init_function,
+						 mDSOHandle,
+						 PLUGIN_INIT_FUNCTION_NAME);
+
+		if(result != APR_SUCCESS)
+		{
+			LL_WARNS("Plugin") << "apr_dso_sym failed with error " << result << LL_ENDL;
+		}
+	}
+	
+	if(result == APR_SUCCESS)
+	{
+		result = init_function(staticReceiveMessage, (void*)this, &mPluginSendMessageFunction, &mPluginUserData);
+
+		if(result != APR_SUCCESS)
+		{
+			LL_WARNS("Plugin") << "call to init function failed with error " << result << LL_ENDL;
+		}
+	}
+	
+	return (int)result;
+}
+
+/** 
+ * Sends a message to the plugin.
+ *
+ * @param[in] message Message
+ */
+void LLPluginInstance::sendMessage(const std::string &message)
+{
+	if(mPluginSendMessageFunction)
+	{
+		LL_DEBUGS("Plugin") << "sending message to plugin: \"" << message << "\"" << LL_ENDL;
+		mPluginSendMessageFunction(message.c_str(), &mPluginUserData);
+	}
+	else
+	{
+		LL_WARNS("Plugin") << "dropping message: \"" << message << "\"" << LL_ENDL;
+	}
+}
+
+/**
+ * Idle. TODO:DOC what's the purpose of this?
+ *
+ */
+void LLPluginInstance::idle(void)
+{
+}
+
+// static
+void LLPluginInstance::staticReceiveMessage(const char *message_string, void **user_data)
+{
+	// TODO: validate that the user_data argument is still a valid LLPluginInstance pointer
+	// we could also use a key that's looked up in a map (instead of a direct pointer) for safety, but that's probably overkill
+	LLPluginInstance *self = (LLPluginInstance*)*user_data;
+	self->receiveMessage(message_string);
+}
+
+/**
+ * Plugin receives message from plugin loader shell.
+ *
+ * @param[in] message_string Message
+ */
+void LLPluginInstance::receiveMessage(const char *message_string)
+{
+	if(mOwner)
+	{
+		LL_DEBUGS("Plugin") << "processing incoming message: \"" << message_string << "\"" << LL_ENDL;		
+		mOwner->receivePluginMessage(message_string);
+	}
+	else
+	{
+		LL_WARNS("Plugin") << "dropping incoming message: \"" << message_string << "\"" << LL_ENDL;		
+	}	
+}