reduce queue size to camInstance.buffer_frame_count_-1 , not just by 1 item

[bjudkewitz]

In this section where we handle full queues...

PyVCAM/src/pyvcam/pvcmodule.cpp

Lines 291 to 302 in 06f7eee

	if (!camInstance.seqMode_){
	if ((int)camInstance.frameQueue_.size() >= camInstance.buffer_frame_count_) {
	//printf("Queue size: %zd",camInstance.frameQueue_.size());
	//printf("Buffer size: %zd",camInstance.buffer_frame_count_);
	camInstance.frameQueue_.pop();
	printf("Lost frame\n");
	}
	}
	frame.count = camInstance.frameCnt_;
	camInstance.frameQueue_.push(frame);
	camInstance.newData_ = true;

... I believe we should reduce the queue size down to (camInstance.buffer_frame_count_-1) , not just by -1. Imagine that the system is temporarily overloaded and the queue size grows multiple items beyond camInstance.buffer_frame_count_. It has no chance of getting reduced again because a few lines further down we always push one frame back in.

So I believe we need a while loop

if ((int)camInstance.frameQueue_.size() >= camInstance.buffer_frame_count_) { 
   int n_dropped = 0
    while ((int)camInstance.frameQueue_.size() >= camInstance.buffer_frame_count_) { 
        camInstance.frameQueue_.pop(); 
        n_dropped++
    }
    printf("Dropped %zd frame(s)\n", n_dropped); 
}

[johandinox]

Yes, that's safer!