1 files changed, 65 insertions, 0 deletions

diff --git a/linden/indra/llcommon/llerror.cpp b/linden/indra/llcommon/llerror.cpp
index 5e520af..a0e42c1 100644
--- a/linden/indra/llcommon/llerror.cpp
+++ b/linden/indra/llcommon/llerror.cpp
@@ -1242,9 +1242,62 @@ namespace LLError
         char** LLCallStacks::sBuffer = NULL ;
         S32    LLCallStacks::sIndex  = 0 ;
 
+        class CallStacksLogLock
+        {
+        public:
+                CallStacksLogLock();
+                ~CallStacksLogLock();
+                bool ok() const { return mOK; }
+        private:
+                bool mLocked;
+                bool mOK;
+        };
+        
+        CallStacksLogLock::CallStacksLogLock()
+                : mLocked(false), mOK(false)
+        {
+                if (!gCallStacksLogMutexp)
+                {
+                        mOK = true;
+                        return;
+                }
+                
+                const int MAX_RETRIES = 5;
+                for (int attempts = 0; attempts < MAX_RETRIES; ++attempts)
+                {
+                        apr_status_t s = apr_thread_mutex_trylock(gCallStacksLogMutexp);
+                        if (!APR_STATUS_IS_EBUSY(s))
+                        {
+                                mLocked = true;
+                                mOK = true;
+                                return;
+                        }
+
+                        ms_sleep(1);
+                }
+
+                // We're hosed, we can't get the mutex.  Blah.
+                std::cerr << "CallStacksLogLock::CallStacksLogLock: failed to get mutex for log"
+                                        << std::endl;
+        }
+        
+        CallStacksLogLock::~CallStacksLogLock()
+        {
+                if (mLocked)
+                {
+                        apr_thread_mutex_unlock(gCallStacksLogMutexp);
+                }
+        }
+
         //static
    void LLCallStacks::push(const char* function, const int line)
    {
+           CallStacksLogLock lock;
+       if (!lock.ok())
+       {
+           return;
+       }
+
            if(!sBuffer)
            {
                    sBuffer = new char*[512] ;
@@ -1280,6 +1333,12 @@ namespace LLError
    //static
    void LLCallStacks::end(std::ostringstream* _out)
    {
+           CallStacksLogLock lock;
+       if (!lock.ok())
+       {
+           return;
+       }
+
            if(!sBuffer)
            {
                    sBuffer = new char*[512] ;
@@ -1302,6 +1361,12 @@ namespace LLError
    //static
    void LLCallStacks::print()
    {
+           CallStacksLogLock lock;
+       if (!lock.ok())
+       {
+           return;
+       }
+
        if(sIndex > 0)
        {
            llinfos << " ************* PRINT OUT LL CALL STACKS ************* " << llendl ;