Segmentation fault during fast write-read on linux

[adixmasz]

Hi,
in read function you don't use mutex. So there is a race condition. Code start from line 117 in file HidApi.cpp:

       bool isTimeout = true;
        while( (std::clock()-start) < end )
        {
            if( this->readAvailable() > 0 )
            {
                ret = this->readFifoBuffer.front();
                this->readFifoBuffer.pop();
                isTimeout = false;
                break;
            }
        }
    }

Segmentation fault can be rise in line:

                this->readFifoBuffer.pop();

when device thread is during change te readFifoBuffer.

Resolve:
I've make "pthread_mutex_t runningMutex;" public in class HidDeviceReaderThread.
Then I've change read function to this:

       bool isTimeout = true;
        while( (std::clock()-start) < end )
        {
            #ifdef OS_LINUX
            pthread_mutex_lock( &(this->backgroundReader->runningMutex));
            #endif

            if( this->readAvailable() > 0 )
            {
                ret = this->readFifoBuffer.front();
                this->readFifoBuffer.pop();
                isTimeout = false;

                #ifdef OS_LINUX
                pthread_mutex_unlock( &(this->backgroundReader->runningMutex));
                #endif
                break;
            }
            else
            {
                #ifdef OS_LINUX
                pthread_mutex_unlock( &(this->backgroundReader->runningMutex));
                #endif
            }
        }
    }

Now it works fine.