SL-10297: Eliminate llerror.cpp's Globals::messageStream and bool.

Instead of a single std::ostringstream instance shared by all callers, even
those on different threads, make each of the relevant lllog_test_() and
llcallstacks macros instantiate independent (stack) std::ostringstream
objects. lllog_test_() is called by LL_DEBUGS(), LLINFOS(), LL_WARNS(),
LL_ERRS(), LL_VLOGS() et al.

Eliminate LLError::Log::out(), whose sole function was to arbitrate use of
that shared std::ostringstream. Amusingly, if the lock couldn't be locked or
if messageStreamInUse was set, out() would allocate a new (heap!)
std::ostringstream anyway, which would then have to be freed by flush().

Make both LLError::Log::flush() overloads accept const std::ostringstream&.
Make LL_ENDL pass the local _out instance. This eliminates the need to check
whether the passed std::ostringstream* references the shared instance and
(if so) reset it or (if not) delete it.

Make LLError::LLCallStacks::insert() accept the local _out instance as non-
const std::ostream&, rather than acquiring and returning std::ostringstream*.
Make end() accept the local instance as const std::ostringstream&.

2 files changed, 26 insertions, 77 deletions

diff --git a/indra/llcommon/llerror.cpp b/indra/llcommon/llerror.cpp
index 9d775dcef3..f7594ed815 100644
--- a/indra/llcommon/llerror.cpp
+++ b/indra/llcommon/llerror.cpp
@@ -442,8 +442,6 @@ namespace
     protected:
 		Globals();
 	public:
-		std::ostringstream messageStream;
-		bool messageStreamInUse;
 		std::string mFatalMessage;
 
 		void addCallSite(LLError::CallSite&);
@@ -453,12 +451,7 @@ namespace
 		CallSiteVector callSites;
 	};
 
-	Globals::Globals()
-		: messageStream(),
-		messageStreamInUse(false),
-		callSites()
-	{
-	}
+	Globals::Globals() {}
 
     Globals* Globals::getInstance()
     {
@@ -1359,25 +1352,7 @@ namespace LLError
 	}
 
 
-	std::ostringstream* Log::out()
-	{
-		LLMutexTrylock lock(getMutex<LOG_MUTEX>(),5);
-
-		if (lock.isLocked())
-		{
-			Globals* g = Globals::getInstance();
-
-			if (!g->messageStreamInUse)
-			{
-				g->messageStreamInUse = true;
-				return &g->messageStream;
-			}
-		}
-
-		return new std::ostringstream;
-	}
-
-	void Log::flush(std::ostringstream* out, char* message)
+	void Log::flush(const std::ostringstream& out, char* message)
 	{
 		LLMutexTrylock lock(getMutex<LOG_MUTEX>(),5);
 		if (!lock.isLocked())
@@ -1385,31 +1360,18 @@ namespace LLError
 			return;
 		}
 
-		if(strlen(out->str().c_str()) < 128)
+		if(strlen(out.str().c_str()) < 128)
 		{
-			strcpy(message, out->str().c_str());
+			strcpy(message, out.str().c_str());
 		}
 		else
 		{
-			strncpy(message, out->str().c_str(), 127);
+			strncpy(message, out.str().c_str(), 127);
 			message[127] = '\0' ;
 		}
-
-		Globals* g = Globals::getInstance();
-		if (out == &g->messageStream)
-		{
-			g->messageStream.clear();
-			g->messageStream.str("");
-			g->messageStreamInUse = false;
-		}
-		else
-		{
-			delete out;
-		}
-		return ;
 	}
 
-	void Log::flush(std::ostringstream* out, const CallSite& site)
+	void Log::flush(const std::ostringstream& out, const CallSite& site)
 	{
 		LLMutexTrylock lock(getMutex<LOG_MUTEX>(),5);
 		if (!lock.isLocked())
@@ -1420,18 +1382,7 @@ namespace LLError
 		Globals* g = Globals::getInstance();
 		SettingsConfigPtr s = Settings::getInstance()->getSettingsConfig();
 
-		std::string message = out->str();
-		if (out == &g->messageStream)
-		{
-			g->messageStream.clear();
-			g->messageStream.str("");
-			g->messageStreamInUse = false;
-		}
-		else
-		{
-			delete out;
-		}
-
+		std::string message = out.str();
 
 		if (site.mPrintOnce)
 		{
@@ -1600,15 +1551,13 @@ namespace LLError
     }
 
     //static
-    std::ostringstream* LLCallStacks::insert(const char* function, const int line)
+    void LLCallStacks::insert(std::ostream& out, const char* function, const int line)
     {
-        std::ostringstream* _out = LLError::Log::out();
-        *_out << function << " line " << line << " " ;
-        return _out ;
+        out << function << " line " << line << " " ;
     }
 
     //static
-    void LLCallStacks::end(std::ostringstream* _out)
+    void LLCallStacks::end(const std::ostringstream& out)
     {
         LLMutexTrylock lock(getMutex<STACKS_MUTEX>(), 5);
         if (!lock.isLocked())
@@ -1626,7 +1575,7 @@ namespace LLError
             clear() ;
         }
 
-        LLError::Log::flush(_out, sBuffer[sIndex++]) ;
+        LLError::Log::flush(out, sBuffer[sIndex++]) ;
     }
 
     //static
diff --git a/indra/llcommon/llerror.h b/indra/llcommon/llerror.h
index f8c0d03aea..51423350e6 100644
--- a/indra/llcommon/llerror.h
+++ b/indra/llcommon/llerror.h
@@ -198,9 +198,8 @@ namespace LLError
 	{
 	public:
 		static bool shouldLog(CallSite&);
-		static std::ostringstream* out();
-		static void flush(std::ostringstream* out, char* message);
-		static void flush(std::ostringstream*, const CallSite&);
+		static void flush(const std::ostringstream& out, char* message);
+		static void flush(const std::ostringstream&, const CallSite&);
 		static std::string demangle(const char* mangled);
 		/// classname<TYPE>()
 		template <typename T>
@@ -289,10 +288,10 @@ namespace LLError
               
     public:   
         static void push(const char* function, const int line) ;
-        static std::ostringstream* insert(const char* function, const int line) ;
+        static void insert(std::ostream& out, const char* function, const int line) ;
         static void print() ;
         static void clear() ;
-        static void end(std::ostringstream* _out) ;
+        static void end(const std::ostringstream& out) ;
         static void cleanup();
     };
 
@@ -306,10 +305,11 @@ namespace LLError
 //this is cheaper than llcallstacks if no need to output other variables to call stacks. 
 #define LL_PUSH_CALLSTACKS() LLError::LLCallStacks::push(__FUNCTION__, __LINE__)
 
-#define llcallstacks                                                                      \
-	{                                                                                     \
-       std::ostringstream* _out = LLError::LLCallStacks::insert(__FUNCTION__, __LINE__) ; \
-       (*_out)
+#define llcallstacks                                                    \
+	{                                                                   \
+		std::ostringstream _out;                                        \
+		LLError::LLCallStacks::insert(_out, __FUNCTION__, __LINE__) ;   \
+		_out
 
 #define llcallstacksendl                   \
 		LLError::End();                    \
@@ -355,11 +355,11 @@ typedef LLError::NoClassInfo _LL_CLASS_TO_LOG;
 		static LLError::CallSite _site(lllog_site_args_(level, once, tags)); \
 		lllog_test_()
 
-#define lllog_test_()                                       \
-		if (LL_UNLIKELY(_site.shouldLog()))                 \
-		{                                                   \
-			std::ostringstream* _out = LLError::Log::out(); \
-			(*_out)
+#define lllog_test_()                           \
+		if (LL_UNLIKELY(_site.shouldLog()))     \
+		{                                       \
+			std::ostringstream _out;            \
+			_out
 
 #define lllog_site_args_(level, once, tags)                 \
 	level, __FILE__, __LINE__, typeid(_LL_CLASS_TO_LOG),    \
@@ -378,7 +378,7 @@ typedef LLError::NoClassInfo _LL_CLASS_TO_LOG;
 //	LL_CONT << " for " << t << " seconds" << LL_ENDL;
 //	
 //Such computation is done iff the message will be logged.
-#define LL_CONT	(*_out)
+#define LL_CONT	_out
 
 #define LL_NEWLINE '\n'