fix for SH-2738 and SH-2777, might also help SH-2723: heap corruption

SH-2738: Texture fetching freezes due to LLcurl
SH-2777: viewer crashed on logout in LLCurl::Easy::releaseEasyHandle

indra/llcommon/llthread.h

@@ -187,11 +187,14 @@ public:
 	LLMutexLock(LLMutex* mutex)
 	{
 		mMutex = mutex;
-		mMutex->lock();
+		
+		if(mMutex)
+			mMutex->lock();
 	}
 	~LLMutexLock()
 	{
-		mMutex->unlock();
+		if(mMutex)
+			mMutex->unlock();
 	}
 private:
 	LLMutex* mMutex;

indra/llmessage/llcurl.cpp

@@ -219,11 +219,15 @@ namespace boost
 
 std::set<CURL*> LLCurl::Easy::sFreeHandles;
 std::set<CURL*> LLCurl::Easy::sActiveHandles;
+LLMutex* LLCurl::Easy::sHandleMutexp = NULL ;
 
 //static
 CURL* LLCurl::Easy::allocEasyHandle()
 {
 	CURL* ret = NULL;
+
+	LLMutexLock lock(sHandleMutexp) ;
+
 	if (sFreeHandles.empty())
 	{
 		ret = curl_easy_init();
@@ -251,6 +255,7 @@ void LLCurl::Easy::releaseEasyHandle(CURL* handle)
 		llerrs << "handle cannot be NULL!" << llendl;
 	}
 
+	LLMutexLock lock(sHandleMutexp) ;
 	if (sActiveHandles.find(handle) != sActiveHandles.end())
 	{
 		sActiveHandles.erase(handle);
@@ -519,7 +524,8 @@ LLCurl::Multi::Multi()
 	  mState(STATE_READY),
 	  mDead(FALSE),
 	  mMutexp(NULL),
-	  mDeletionMutexp(NULL)
+	  mDeletionMutexp(NULL),
+	  mEasyMutexp(NULL)
 {
 	mCurlMultiHandle = curl_multi_init();
 	if (!mCurlMultiHandle)
@@ -534,6 +540,7 @@ LLCurl::Multi::Multi()
 	{
 		mMutexp = new LLMutex(NULL) ;
 		mDeletionMutexp = new LLMutex(NULL) ;
+		mEasyMutexp = new LLMutex(NULL) ;
 	}
 	LLCurl::getCurlThread()->addMulti(this) ;
 
@@ -563,6 +570,8 @@ LLCurl::Multi::~Multi()
 	mMutexp = NULL ;
 	delete mDeletionMutexp ;
 	mDeletionMutexp = NULL ;
+	delete mEasyMutexp ;
+	mEasyMutexp = NULL ;
 
 	--gCurlMultiCount;
 }
@@ -585,17 +594,9 @@ void LLCurl::Multi::unlock()
 
 void LLCurl::Multi::markDead()
 {
-	if(mDeletionMutexp)
-	{
-		mDeletionMutexp->lock() ;
-	}
-
+	LLMutexLock lock(mDeletionMutexp) ;
+	
 	mDead = TRUE ;
-
-	if(mDeletionMutexp)
-	{
-		mDeletionMutexp->unlock() ;
-	}
 }
 
 void LLCurl::Multi::setState(LLCurl::Multi::ePerformState state)
@@ -655,10 +656,8 @@ CURLMsg* LLCurl::Multi::info_read(S32* msgs_in_queue)
 //return true if dead
 bool LLCurl::Multi::doPerform()
 {
-	if(mDeletionMutexp)
-	{
-		mDeletionMutexp->lock() ;
-	}
+	LLMutexLock lock(mDeletionMutexp) ;
+	
 	bool dead = mDead ;
 
 	if(mDead)
@@ -675,6 +674,7 @@ bool LLCurl::Multi::doPerform()
 				call_count < MULTI_PERFORM_CALL_REPEAT;
 				call_count++)
 		{
+			LLMutexLock lock(mMutexp) ;
 			CURLMcode code = curl_multi_perform(mCurlMultiHandle, &q);
 			if (CURLM_CALL_MULTI_PERFORM != code || q == 0)
 			{
@@ -688,11 +688,6 @@ bool LLCurl::Multi::doPerform()
 		setState(STATE_COMPLETED) ;
 	}
 
-	if(mDeletionMutexp)
-	{
-		mDeletionMutexp->unlock() ;
-	}
-
 	return dead ;
 }
 
@@ -743,19 +738,21 @@ S32 LLCurl::Multi::process()
 
 LLCurl::Easy* LLCurl::Multi::allocEasy()
 {
-	Easy* easy = 0;
+	Easy* easy = 0;	
 
 	if (mEasyFreeList.empty())
-	{
+	{		
 		easy = Easy::getEasy();
 	}
 	else
 	{
+		LLMutexLock lock(mEasyMutexp) ;
 		easy = *(mEasyFreeList.begin());
 		mEasyFreeList.erase(easy);
 	}
 	if (easy)
 	{
+		LLMutexLock lock(mEasyMutexp) ;
 		mEasyActiveList.insert(easy);
 		mEasyActiveMap[easy->getCurlHandle()] = easy;
 	}
@@ -764,6 +761,7 @@ LLCurl::Easy* LLCurl::Multi::allocEasy()
 
 bool LLCurl::Multi::addEasy(Easy* easy)
 {
+	LLMutexLock lock(mMutexp) ;
 	CURLMcode mcode = curl_multi_add_handle(mCurlMultiHandle, easy->getCurlHandle());
 	check_curl_multi_code(mcode);
 	//if (mcode != CURLM_OK)
@@ -776,22 +774,30 @@ bool LLCurl::Multi::addEasy(Easy* easy)
 
 void LLCurl::Multi::easyFree(Easy* easy)
 {
+	mEasyMutexp->lock() ;
 	mEasyActiveList.erase(easy);
 	mEasyActiveMap.erase(easy->getCurlHandle());
+
 	if (mEasyFreeList.size() < EASY_HANDLE_POOL_SIZE)
-	{
-		easy->resetState();
+	{		
 		mEasyFreeList.insert(easy);
+		mEasyMutexp->unlock() ;
+
+		easy->resetState();
 	}
 	else
 	{
+		mEasyMutexp->unlock() ;
 		delete easy;
 	}
 }
 
 void LLCurl::Multi::removeEasy(Easy* easy)
 {
-	check_curl_multi_code(curl_multi_remove_handle(mCurlMultiHandle, easy->getCurlHandle()));
+	{
+		LLMutexLock lock(mMutexp) ;
+		check_curl_multi_code(curl_multi_remove_handle(mCurlMultiHandle, easy->getCurlHandle()));
+	}
 	easyFree(easy);
 }
 
@@ -1290,6 +1296,10 @@ void LLCurl::initClass(bool multi_threaded)
 #endif
 
 	sCurlThread = new LLCurlThread(multi_threaded) ;
+	if(multi_threaded)
+	{
+		Easy::sHandleMutexp = new LLMutex(NULL) ;
+	}
 }
 
 void LLCurl::cleanupClass()
@@ -1319,6 +1329,9 @@ void LLCurl::cleanupClass()
 
 	Easy::sFreeHandles.clear();
 
+	delete Easy::sHandleMutexp ;
+	Easy::sHandleMutexp = NULL ;
+
 	llassert(Easy::sActiveHandles.empty());
 }
 

indra/llmessage/llcurl.h

@@ -253,6 +253,7 @@ private:
 
 	static std::set<CURL*> sFreeHandles;
 	static std::set<CURL*> sActiveHandles;
+	static LLMutex*        sHandleMutexp ;
 };
 
 class LLCurl::Multi
@@ -316,6 +317,7 @@ private:
 	BOOL mDead ;
 	LLMutex* mMutexp ;
 	LLMutex* mDeletionMutexp ;
+	LLMutex* mEasyMutexp ;
 };
 
 class LLCurlThread : public LLQueuedThread