1 files changed, 70 insertions, 7 deletions

diff --git a/indra/llplugin/llpluginprocesschild.cpp b/indra/llplugin/llpluginprocesschild.cpp
index ccaf95b36d..d1cf91b253 100644
--- a/indra/llplugin/llpluginprocesschild.cpp
+++ b/indra/llplugin/llpluginprocesschild.cpp
@@ -48,6 +48,8 @@ LLPluginProcessChild::LLPluginProcessChild()
 	mSocket = LLSocket::create(gAPRPoolp, LLSocket::STREAM_TCP);
 	mSleepTime = PLUGIN_IDLE_SECONDS;	// default: send idle messages at 100Hz
 	mCPUElapsed = 0.0f;
+	mBlockingRequest = false;
+	mBlockingResponseReceived = false;
 }
 
 LLPluginProcessChild::~LLPluginProcessChild()
@@ -83,9 +85,14 @@ void LLPluginProcessChild::idle(void)
 	bool idle_again;
 	do
 	{
-		if(mSocketError != APR_SUCCESS)
+		if(APR_STATUS_IS_EOF(mSocketError))
 		{
-			LL_INFOS("Plugin") << "message pipe is in error state, moving to STATE_ERROR"<< LL_ENDL;
+			// Plugin socket was closed.  This covers both normal plugin termination and host crashes.
+			setState(STATE_ERROR);
+		}
+		else if(mSocketError != APR_SUCCESS)
+		{
+			LL_INFOS("Plugin") << "message pipe is in error state (" << mSocketError << "), moving to STATE_ERROR"<< LL_ENDL;
 			setState(STATE_ERROR);
 		}	
 
@@ -226,6 +233,7 @@ void LLPluginProcessChild::idle(void)
 
 void LLPluginProcessChild::sleep(F64 seconds)
 {
+	deliverQueuedMessages();
 	if(mMessagePipe)
 	{
 		mMessagePipe->pump(seconds);
@@ -238,6 +246,7 @@ void LLPluginProcessChild::sleep(F64 seconds)
 
 void LLPluginProcessChild::pump(void)
 {
+	deliverQueuedMessages();
 	if(mMessagePipe)
 	{
 		mMessagePipe->pump(0.0f);
@@ -309,15 +318,32 @@ void LLPluginProcessChild::receiveMessageRaw(const std::string &message)
 
 	LL_DEBUGS("Plugin") << "Received from parent: " << message << LL_ENDL;
 
+	// Decode this message
+	LLPluginMessage parsed;
+	parsed.parse(message);
+
+	if(mBlockingRequest)
+	{
+		// We're blocking the plugin waiting for a response.
+
+		if(parsed.hasValue("blocking_response"))
+		{
+			// This is the message we've been waiting for -- fall through and send it immediately. 
+			mBlockingResponseReceived = true;
+		}
+		else
+		{
+			// Still waiting.  Queue this message and don't process it yet.
+			mMessageQueue.push(message);
+			return;
+		}
+	}
+	
 	bool passMessage = true;
 	
 	// FIXME: how should we handle queueing here?
 	
 	{
-		// Decode this message
-		LLPluginMessage parsed;
-		parsed.parse(message);
-		
 		std::string message_class = parsed.getClass();
 		if(message_class == LLPLUGIN_MESSAGE_CLASS_INTERNAL)
 		{
@@ -425,7 +451,13 @@ void LLPluginProcessChild::receiveMessageRaw(const std::string &message)
 void LLPluginProcessChild::receivePluginMessage(const std::string &message)
 {
 	LL_DEBUGS("Plugin") << "Received from plugin: " << message << LL_ENDL;
-
+	
+	if(mBlockingRequest)
+	{
+		// 
+		LL_ERRS("Plugin") << "Can't send a message while already waiting on a blocking request -- aborting!" << LL_ENDL;
+	}
+	
 	// Incoming message from the plugin instance
 	bool passMessage = true;
 
@@ -436,6 +468,12 @@ void LLPluginProcessChild::receivePluginMessage(const std::string &message)
 		// Decode this message
 		LLPluginMessage parsed;
 		parsed.parse(message);
+		
+		if(parsed.hasValue("blocking_request"))
+		{
+			mBlockingRequest = true;
+		}
+
 		std::string message_class = parsed.getClass();
 		if(message_class == "base")
 		{
@@ -494,6 +532,19 @@ void LLPluginProcessChild::receivePluginMessage(const std::string &message)
 		LL_DEBUGS("Plugin") << "Passing through to parent: " << message << LL_ENDL;
 		writeMessageRaw(message);
 	}
+	
+	while(mBlockingRequest)
+	{
+		// The plugin wants to block and wait for a response to this message.
+		sleep(mSleepTime);	// this will pump the message pipe and process messages
+
+		if(mBlockingResponseReceived || mSocketError != APR_SUCCESS || (mMessagePipe == NULL))
+		{
+			// Response has been received, or we've hit an error state.  Stop waiting.
+			mBlockingRequest = false;
+			mBlockingResponseReceived = false;
+		}
+	}
 }
 
 
@@ -502,3 +553,15 @@ void LLPluginProcessChild::setState(EState state)
 	LL_DEBUGS("Plugin") << "setting state to " << state << LL_ENDL;
 	mState = state; 
 };
+
+void LLPluginProcessChild::deliverQueuedMessages()
+{
+	if(!mBlockingRequest)
+	{
+		while(!mMessageQueue.empty())
+		{
+			receiveMessageRaw(mMessageQueue.front());
+			mMessageQueue.pop();
+		}
+	}
+}