Fixed web browser thanks to ArminW/Imprudence

indra/llplugin/llpluginprocessparent.cpp

@@ -2,9 +2,10 @@
  * @file llpluginprocessparent.cpp
  * @brief LLPluginProcessParent handles the parent side of the external-process plugin API.
  *
+ * @cond
  * $LicenseInfo:firstyear=2008&license=viewergpl$
  * 
- * Copyright (c) 2008-2009, Linden Research, Inc.
+ * Copyright (c) 2008-2010, Linden Research, Inc.
  * 
  * Second Life Viewer Source Code
  * The source code in this file ("Source Code") is provided by Linden Lab
@@ -12,13 +13,13 @@
  * ("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
+ * online at http://secondlife.com/developers/opensource/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
+ * http://secondlife.com/developers/opensource/flossexception
  * 
  * By copying, modifying or distributing this software, you acknowledge
  * that you have read and understood your obligations described above,
@@ -28,6 +29,8 @@
  * WARRANTIES, EXPRESS, IMPLIED OR OTHERWISE, REGARDING ITS ACCURACY,
  * COMPLETENESS OR PERFORMANCE.
  * $/LicenseInfo$
+ * 
+ * @endcond
  */
 
 #include "linden_common.h"
@@ -44,25 +47,90 @@ LLPluginProcessParentOwner::~LLPluginProcessParentOwner()
 	
 }
 
-LLPluginProcessParent::LLPluginProcessParent(LLPluginProcessParentOwner *owner)
+bool LLPluginProcessParent::sUseReadThread = false;
+apr_pollset_t *LLPluginProcessParent::sPollSet = NULL;
+bool LLPluginProcessParent::sPollsetNeedsRebuild = false;
+LLMutex *LLPluginProcessParent::sInstancesMutex;
+std::list<LLPluginProcessParent*> LLPluginProcessParent::sInstances;
+LLThread *LLPluginProcessParent::sReadThread = NULL;
+
+
+class LLPluginProcessParentPollThread: public LLThread
 {
+public:
+	LLPluginProcessParentPollThread() :
+		LLThread("LLPluginProcessParentPollThread", gAPRPoolp)
+	{
+	}
+protected:
+	// Inherited from LLThread
+	/*virtual*/ void run(void)
+	{
+		while(!isQuitting() && LLPluginProcessParent::getUseReadThread())
+		{
+			LLPluginProcessParent::poll(0.1f);
+			checkPause();
+		}
+		
+		// Final poll to clean up the pollset, etc.
+		LLPluginProcessParent::poll(0.0f);
+	} 
+
+	// Inherited from LLThread
+	/*virtual*/ bool runCondition(void)
+	{
+		return(LLPluginProcessParent::canPollThreadRun());
+	}
+
+};
+
+LLPluginProcessParent::LLPluginProcessParent(LLPluginProcessParentOwner *owner):
+	mIncomingQueueMutex(gAPRPoolp)
+{
+	if(!sInstancesMutex)
+	{
+		sInstancesMutex = new LLMutex(gAPRPoolp);
+	}
+	
 	mOwner = owner;
 	mBoundPort = 0;
 	mState = STATE_UNINITIALIZED;
+	mSleepTime = 0.0;
+	mCPUUsage = 0.0;
 	mDisableTimeout = false;
 	mDebug = false;
+	mBlocked = false;
+	mPolledInput = false;
+	mPollFD.client_data = NULL;
 
 	mPluginLaunchTimeout = 60.0f;
 	mPluginLockupTimeout = 15.0f;
 	
 	// Don't start the timer here -- start it when we actually launch the plugin process.
 	mHeartbeat.stop();
+
+	
+	// Don't add to the global list until fully constructed.
+	{
+		LLMutexLock lock(sInstancesMutex);
+		sInstances.push_back(this);
+	}
 }
 
 LLPluginProcessParent::~LLPluginProcessParent()
 {
 	LL_DEBUGS("Plugin") << "destructor" << LL_ENDL;
 
+	// Remove from the global list before beginning destruction.
+	{
+		// Make sure to get the global mutex _first_ here, to avoid a possible deadlock against LLPluginProcessParent::poll()
+		LLMutexLock lock(sInstancesMutex);
+		{
+			LLMutexLock lock2(&mIncomingQueueMutex);
+			sInstances.remove(this);
+		}
+	}
+
 	// Destroy any remaining shared memory regions
 	sharedMemoryRegionsType::iterator iter;
 	while((iter = mSharedMemoryRegions.begin()) != mSharedMemoryRegions.end())
@@ -74,15 +142,17 @@ LLPluginProcessParent::~LLPluginProcessParent()
 		mSharedMemoryRegions.erase(iter);
 	}
 	
-	// orphaning the process means it won't be killed when the LLProcessLauncher is destructed.
-	// This is what we want -- it should exit cleanly once it notices the sockets have been closed.
-	mProcess.orphan();
+	mProcess.kill();
 	killSockets();
 }
 
 void LLPluginProcessParent::killSockets(void)
 {
-	killMessagePipe();
+	{
+		LLMutexLock lock(&mIncomingQueueMutex);
+		killMessagePipe();
+	}
+
 	mListenSocket.reset();
 	mSocket.reset();
 }
@@ -95,14 +165,12 @@ void LLPluginProcessParent::errorState(void)
 		setState(STATE_ERROR);
 }
 
-void LLPluginProcessParent::init(const std::string &launcher_filename, const std::string &plugin_filename, bool debug, const std::string &user_data_path)
+void LLPluginProcessParent::init(const std::string &launcher_filename, const std::string &plugin_filename, bool debug)
 {	
 	mProcess.setExecutable(launcher_filename);
 	mPluginFile = plugin_filename;
 	mCPUUsage = 0.0f;
-	mDebug = debug;
-	mUserDataPath = user_data_path;
-	
+	mDebug = debug;	
 	setState(STATE_INITIALIZED);
 }
 
@@ -158,21 +226,47 @@ void LLPluginProcessParent::idle(void)
 
 	do
 	{
+		// process queued messages
+		mIncomingQueueMutex.lock();
+		while(!mIncomingQueue.empty())
+		{
+			LLPluginMessage message = mIncomingQueue.front();
+			mIncomingQueue.pop();
+			mIncomingQueueMutex.unlock();
+				
+			receiveMessage(message);
+			
+			mIncomingQueueMutex.lock();
+		}
+
+		mIncomingQueueMutex.unlock();
+		
 		// Give time to network processing
 		if(mMessagePipe)
 		{
-			if(!mMessagePipe->pump())
+			// Drain any queued outgoing messages
+			mMessagePipe->pumpOutput();
+			
+			// Only do input processing here if this instance isn't in a pollset.
+			if(!mPolledInput)
 			{
-//				LL_WARNS("Plugin") << "Message pipe hit an error state" << LL_ENDL;
-				errorState();
+				mMessagePipe->pumpInput();
 			}
 		}
-
-		if((mSocketError != APR_SUCCESS) && (mState <= STATE_RUNNING))
+		
+		if(mState <= STATE_RUNNING)
 		{
-			// The socket is in an error state -- the plugin is gone.
-			LL_WARNS("Plugin") << "Socket hit an error state (" << mSocketError << ")" << LL_ENDL;
-			errorState();
+			if(APR_STATUS_IS_EOF(mSocketError))
+			{
+				// Plugin socket was closed.  This covers both normal plugin termination and plugin crashes.
+				errorState();
+			}
+			else if(mSocketError != APR_SUCCESS)
+			{
+				// The socket is in an error state -- the plugin is gone.
+				LL_WARNS("Plugin") << "Socket hit an error state (" << mSocketError << ")" << LL_ENDL;
+				errorState();
+			}
 		}	
 		
 		// If a state needs to go directly to another state (as a performance enhancement), it can set idle_again to true after calling setState().
@@ -314,6 +408,17 @@ void LLPluginProcessParent::idle(void)
 						mDebugger.addArgument("end tell");
 						mDebugger.launch();
 
+						#elif LL_LINUX
+
+						std::stringstream cmd;
+
+						mDebugger.setExecutable("/usr/bin/gnome-terminal");
+						mDebugger.addArgument("--geometry=165x24-0+0");
+						mDebugger.addArgument("-e");
+						cmd << "/usr/bin/gdb -n /proc/" << mProcess.getProcessID() << "/exe " << mProcess.getProcessID();
+						mDebugger.addArgument(cmd.str());
+						mDebugger.launch();
+
 						#endif
 					}
 					
@@ -353,13 +458,12 @@ void LLPluginProcessParent::idle(void)
 			break;
 
 			case STATE_HELLO:
-				LL_DEBUGS("Plugin") << "received hello message" << llendl;
+				LL_DEBUGS("Plugin") << "received hello message" << LL_ENDL;
 				
 				// Send the message to load the plugin
 				{
 					LLPluginMessage message(LLPLUGIN_MESSAGE_CLASS_INTERNAL, "load_plugin");
 					message.setValue("file", mPluginFile);
-					message.setValue("user_data_path", mUserDataPath);
 					sendMessage(message);
 				}
 
@@ -388,7 +492,7 @@ void LLPluginProcessParent::idle(void)
 				}
 				else if(pluginLockedUp())
 				{
-					LL_WARNS("Plugin") << "timeout in exiting state, bailing out" << llendl;
+					LL_WARNS("Plugin") << "timeout in exiting state, bailing out" << LL_ENDL;
 					errorState();
 				}
 			break;
@@ -410,8 +514,7 @@ void LLPluginProcessParent::idle(void)
 			break;
 			
 			case STATE_CLEANUP:
-				// Don't do a kill here anymore -- closing the sockets is the new 'kill'.
-				mProcess.orphan();
+				mProcess.kill();
 				killSockets();
 				setState(STATE_DONE);
 			break;
@@ -479,23 +582,323 @@ void LLPluginProcessParent::setSleepTime(F64 sleep_time, bool force_send)
 
 void LLPluginProcessParent::sendMessage(const LLPluginMessage &message)
 {
+	if(message.hasValue("blocking_response"))
+	{
+		mBlocked = false;
+
+		// reset the heartbeat timer, since there will have been no heartbeats while the plugin was blocked.
+		mHeartbeat.setTimerExpirySec(mPluginLockupTimeout);
+	}
 	
 	std::string buffer = message.generate();
 	LL_DEBUGS("Plugin") << "Sending: " << buffer << LL_ENDL;	
 	writeMessageRaw(buffer);
+	
+	// Try to send message immediately.
+	if(mMessagePipe)
+	{
+		mMessagePipe->pumpOutput();
+	}
 }
 
+//virtual 
+void LLPluginProcessParent::setMessagePipe(LLPluginMessagePipe *message_pipe)
+{
+	bool update_pollset = false;
+	
+	if(mMessagePipe)
+	{
+		// Unsetting an existing message pipe -- remove from the pollset		
+		mPollFD.client_data = NULL;
+
+		// pollset needs an update
+		update_pollset = true;
+	}
+	if(message_pipe != NULL)
+	{
+		// Set up the apr_pollfd_t
+		mPollFD.p = gAPRPoolp;
+		mPollFD.desc_type = APR_POLL_SOCKET;
+		mPollFD.reqevents = APR_POLLIN|APR_POLLERR|APR_POLLHUP;
+		mPollFD.rtnevents = 0;
+		mPollFD.desc.s = mSocket->getSocket();
+		mPollFD.client_data = (void*)this;	
+		
+		// pollset needs an update
+		update_pollset = true;
+	}
+
+	mMessagePipe = message_pipe;
+	
+	if(update_pollset)
+	{
+		dirtyPollSet();
+	}
+}
+
+//static 
+void LLPluginProcessParent::dirtyPollSet()
+{
+	sPollsetNeedsRebuild = true;
+	
+	if(sReadThread)
+	{
+		LL_DEBUGS("PluginPoll") << "unpausing read thread " << LL_ENDL;
+		sReadThread->unpause();
+	}
+}
+
+void LLPluginProcessParent::updatePollset()
+{
+	if(!sInstancesMutex)
+	{
+		// No instances have been created yet.  There's no work to do.
+		return;
+	}
+		
+	LLMutexLock lock(sInstancesMutex);
+
+	if(sPollSet)
+	{
+		LL_DEBUGS("PluginPoll") << "destroying pollset " << sPollSet << LL_ENDL;
+		// delete the existing pollset.
+		apr_pollset_destroy(sPollSet);
+		sPollSet = NULL;
+	}
+	
+	std::list<LLPluginProcessParent*>::iterator iter;
+	int count = 0;
+	
+	// Count the number of instances that want to be in the pollset
+	for(iter = sInstances.begin(); iter != sInstances.end(); iter++)
+	{
+		(*iter)->mPolledInput = false;
+		if((*iter)->mPollFD.client_data)
+		{
+			// This instance has a socket that needs to be polled.
+			++count;
+		}
+	}
+
+	if(sUseReadThread && sReadThread && !sReadThread->isQuitting())
+	{
+		if(!sPollSet && (count > 0))
+		{
+#ifdef APR_POLLSET_NOCOPY
+			// The pollset doesn't exist yet.  Create it now.
+			apr_status_t status = apr_pollset_create(&sPollSet, count, gAPRPoolp, APR_POLLSET_NOCOPY);
+			if(status != APR_SUCCESS)
+			{
+#endif // APR_POLLSET_NOCOPY
+				LL_WARNS("PluginPoll") << "Couldn't create pollset.  Falling back to non-pollset mode." << LL_ENDL;
+				sPollSet = NULL;
+#ifdef APR_POLLSET_NOCOPY
+			}
+			else
+			{
+				LL_DEBUGS("PluginPoll") << "created pollset " << sPollSet << LL_ENDL;
+				
+				// Pollset was created, add all instances to it.
+				for(iter = sInstances.begin(); iter != sInstances.end(); iter++)
+				{
+					if((*iter)->mPollFD.client_data)
+					{
+						status = apr_pollset_add(sPollSet, &((*iter)->mPollFD));
+						if(status == APR_SUCCESS)
+						{
+							(*iter)->mPolledInput = true;
+						}
+						else
+						{
+							LL_WARNS("PluginPoll") << "apr_pollset_add failed with status " << status << LL_ENDL;
+						}
+					}
+				}
+			}
+#endif // APR_POLLSET_NOCOPY
+		}
+	}
+}
+
+void LLPluginProcessParent::setUseReadThread(bool use_read_thread)
+{
+	if(sUseReadThread != use_read_thread)
+	{
+		sUseReadThread = use_read_thread;
+		
+		if(sUseReadThread)
+		{
+			if(!sReadThread)
+			{
+				// start up the read thread
+				LL_INFOS("PluginPoll") << "creating read thread " << LL_ENDL;
+
+				// make sure the pollset gets rebuilt.
+				sPollsetNeedsRebuild = true;
+				
+				sReadThread = new LLPluginProcessParentPollThread;
+				sReadThread->start();
+			}
+		}
+		else
+		{
+			if(sReadThread)
+			{
+				// shut down the read thread
+				LL_INFOS("PluginPoll") << "destroying read thread " << LL_ENDL;
+				delete sReadThread;
+				sReadThread = NULL;
+			}
+		}
+
+	}
+}
+
+void LLPluginProcessParent::poll(F64 timeout)
+{
+	if(sPollsetNeedsRebuild || !sUseReadThread)
+	{
+		sPollsetNeedsRebuild = false;
+		updatePollset();
+	}
+	
+	if(sPollSet)
+	{
+		apr_status_t status;
+		apr_int32_t count;
+		const apr_pollfd_t *descriptors;
+		status = apr_pollset_poll(sPollSet, (apr_interval_time_t)(timeout * 1000000), &count, &descriptors);
+		if(status == APR_SUCCESS)
+		{
+			// One or more of the descriptors signalled.  Call them.
+			for(int i = 0; i < count; i++)
+			{
+				LLPluginProcessParent *self = (LLPluginProcessParent *)(descriptors[i].client_data);
+				// NOTE: the descriptor returned here is actually a COPY of the original (even though we create the pollset with APR_POLLSET_NOCOPY).
+				// This means that even if the parent has set its mPollFD.client_data to NULL, the old pointer may still there in this descriptor.
+				// It's even possible that the old pointer no longer points to a valid LLPluginProcessParent.
+				// This means that we can't safely dereference the 'self' pointer here without some extra steps...
+				if(self)
+				{
+					// Make sure this pointer is still in the instances list
+					bool valid = false;
+					{
+						LLMutexLock lock(sInstancesMutex);
+						for(std::list<LLPluginProcessParent*>::iterator iter = sInstances.begin(); iter != sInstances.end(); ++iter)
+						{
+							if(*iter == self)
+							{
+								// Lock the instance's mutex before unlocking the global mutex.  
+								// This avoids a possible race condition where the instance gets deleted between this check and the servicePoll() call.
+								self->mIncomingQueueMutex.lock();
+								valid = true;
+								break;
+							}
+						}
+					}
+					
+					if(valid)
+					{
+						// The instance is still valid.
+						// Pull incoming messages off the socket
+						self->servicePoll();
+						self->mIncomingQueueMutex.unlock();
+					}
+					else
+					{
+						LL_DEBUGS("PluginPoll") << "detected deleted instance " << self << LL_ENDL;
+					}
+
+				}
+			}
+		}
+		else if(APR_STATUS_IS_TIMEUP(status))
+		{
+			// timed out with no incoming data.  Just return.
+		}
+		else if(status == EBADF)
+		{
+			// This happens when one of the file descriptors in the pollset is destroyed, which happens whenever a plugin's socket is closed.
+			// The pollset has been or will be recreated, so just return.
+			LL_DEBUGS("PluginPoll") << "apr_pollset_poll returned EBADF" << LL_ENDL;
+		}
+		else if(status != APR_SUCCESS)
+		{
+			LL_WARNS("PluginPoll") << "apr_pollset_poll failed with status " << status << LL_ENDL;
+		}
+	}
+}
+
+void LLPluginProcessParent::servicePoll()
+{
+	bool result = true;
+	
+	// poll signalled on this object's socket.  Try to process incoming messages.
+	if(mMessagePipe)
+	{
+		result = mMessagePipe->pumpInput(0.0f);
+	}
+
+	if(!result)
+	{
+		// If we got a read error on input, remove this pipe from the pollset
+		apr_pollset_remove(sPollSet, &mPollFD);
+
+		// and tell the code not to re-add it
+		mPollFD.client_data = NULL;
+	}
+}
 
 void LLPluginProcessParent::receiveMessageRaw(const std::string &message)
 {
 	LL_DEBUGS("Plugin") << "Received: " << message << LL_ENDL;
-
-	// FIXME: should this go into a queue instead?
 	
 	LLPluginMessage parsed;
 	if(parsed.parse(message) != -1)
 	{
-		receiveMessage(parsed);
+		if(parsed.hasValue("blocking_request"))
+		{
+			mBlocked = true;
+		}
+
+		if(mPolledInput)
+		{
+			// This is being called on the polling thread -- only do minimal processing/queueing.
+			receiveMessageEarly(parsed);
+		}
+		else
+		{
+			// This is not being called on the polling thread -- do full message processing at this time.
+			receiveMessage(parsed);
+		}
+	}
+}
+
+void LLPluginProcessParent::receiveMessageEarly(const LLPluginMessage &message)
+{
+	// NOTE: this function will be called from the polling thread.  It will be called with mIncomingQueueMutex _already locked_. 
+
+	bool handled = false;
+	
+	std::string message_class = message.getClass();
+	if(message_class == LLPLUGIN_MESSAGE_CLASS_INTERNAL)
+	{
+		// no internal messages need to be handled early.
+	}
+	else
+	{
+		// Call out to the owner and see if they to reply
+		// TODO: Should this only happen when blocked?
+		if(mOwner != NULL)
+		{
+			handled = mOwner->receivePluginMessageEarly(message);
+		}
+	}
+	
+	if(!handled)
+	{
+		// any message that wasn't handled early needs to be queued.
+		mIncomingQueue.push(message);
 	}
 }
 
@@ -681,7 +1084,7 @@ std::string LLPluginProcessParent::getPluginVersion(void)
 
 void LLPluginProcessParent::setState(EState state)
 {
-	LL_DEBUGS("Plugin") << "setting state to " << state << LL_ENDL;
+	LL_DEBUGS("Plugin") << "setting state to " << stateToString(state) << LL_ENDL;
 	mState = state; 
 };
 
@@ -689,18 +1092,15 @@ bool LLPluginProcessParent::pluginLockedUpOrQuit()
 {
 	bool result = false;
 	
-	if(!mDisableTimeout && !mDebug)
+	if(!mProcess.isRunning())
 	{
-		if(!mProcess.isRunning())
-		{
-			LL_WARNS("Plugin") << "child exited" << llendl;
-			result = true;
-		}
-		else if(pluginLockedUp())
-		{
-			LL_WARNS("Plugin") << "timeout" << llendl;
-			result = true;
-		}
+		LL_WARNS("Plugin") << "child exited" << LL_ENDL;
+		result = true;
+	}
+	else if(pluginLockedUp())
+	{
+		LL_WARNS("Plugin") << "timeout" << LL_ENDL;
+		result = true;
 	}
 	
 	return result;
@@ -708,7 +1108,63 @@ bool LLPluginProcessParent::pluginLockedUpOrQuit()
 
 bool LLPluginProcessParent::pluginLockedUp()
 {
+	if(mDisableTimeout || mDebug || mBlocked)
+	{
+		// Never time out a plugin process in these cases.
+		return false;
+	}
+	
 	// If the timer is running and has expired, the plugin has locked up.
 	return (mHeartbeat.getStarted() && mHeartbeat.hasExpired());
 }
 
+std::string LLPluginProcessParent::stateToString(EState state)
+{
+	std::string eng = "unknown plugin state";
+	switch (state)
+	{
+	case STATE_UNINITIALIZED:
+		eng = "STATE_UNINITIALIZED";
+		break;
+	case STATE_INITIALIZED: 
+		eng = "STATE_INITIALIZED - init() has been called";
+		break;
+	case STATE_LISTENING:
+		eng = "STATE_LISTENING - listening for incoming connection";
+		break;
+	case STATE_LAUNCHED:
+		eng = "STATE_LAUNCHED - process has been launched";
+		break;
+	case STATE_CONNECTED:
+		eng = "STATE_CONNECTED - process has connected";
+		break;
+	case STATE_HELLO:
+		eng = "STATE_HELLO - first message from the plugin process has been received";
+		break;
+	case STATE_LOADING:
+		eng = "STATE_LOADING - process has been asked to load the plugin";
+		break;
+	case STATE_RUNNING:
+		eng = "STATE_RUNNING - plugin running";
+		break;
+	case STATE_LAUNCH_FAILURE:
+		eng = "STATE_LAUNCH_FAILURE - failure before plugin loaded";
+		break;
+	case STATE_ERROR:
+		eng = "STATE_ERROR - generic bailout state";
+		break;
+	case STATE_CLEANUP:
+		eng = "STATE_CLEANUP - clean everything up";
+		break;
+	case STATE_EXITING:
+		eng = "STATE_EXITING - tried to kill process, waiting for it to exit";
+		break;
+	case STATE_DONE:
+		eng = "STATE_DONE - plugin done";
+		break;
+	default:
+		break;
+	}
+	
+	return llformat("(%d) ", (S32)state) + eng;
+}