From cd863aa837174f6a3fa5862323d82dab8f0030f8 Mon Sep 17 00:00:00 2001
From: "Steinar H. Gunderson" <sgunderson@bigfoot.com>
Date: Mon, 12 Oct 2015 21:27:47 +0200
Subject: [PATCH] Add support for stopping the dequeue thread.

---
 bmusb.cpp | 16 ++++++++++++----
 bmusb.h   |  5 ++++-
 2 files changed, 16 insertions(+), 5 deletions(-)

diff --git a/bmusb.cpp b/bmusb.cpp
index b2de56f..1079f2a 100644
--- a/bmusb.cpp
+++ b/bmusb.cpp
@@ -144,14 +144,14 @@ void dump_audio_block(uint8_t *audio_start, size_t audio_len)
 	fwrite(audio_start + AUDIO_HEADER_SIZE, 1, audio_len - AUDIO_HEADER_SIZE, audiofp);
 }
 
-void BMUSBCapture::dequeue_thread()
+void BMUSBCapture::dequeue_thread_func()
 {
 	if (has_dequeue_callbacks) {
 		dequeue_init_callback();
 	}
-	for ( ;; ) {
+	while (!dequeue_thread_should_quit) {
 		unique_lock<mutex> lock(queue_lock);
-		queues_not_empty.wait(lock, [this]{ return !pending_video_frames.empty() && !pending_audio_frames.empty(); });
+		queues_not_empty.wait(lock, [this]{ return dequeue_thread_should_quit || (!pending_video_frames.empty() && !pending_audio_frames.empty()); });
 
 		uint16_t video_timecode = pending_video_frames.front().timecode;
 		uint16_t audio_timecode = pending_audio_frames.front().timecode;
@@ -634,7 +634,8 @@ void BMUSBCapture::configure_card()
 	if (audio_frame_allocator == nullptr) {
 		set_audio_frame_allocator(new MallocFrameAllocator(65536));  // FIXME: leak.
 	}
-	thread(&BMUSBCapture::dequeue_thread, this).detach();
+	dequeue_thread_should_quit = false;
+	dequeue_thread = thread(&BMUSBCapture::dequeue_thread_func, this);
 
 	int rc;
 	struct libusb_transfer *xfr;
@@ -937,6 +938,13 @@ out:
 #endif
 }
 
+void BMUSBCapture::stop_dequeue_thread()
+{
+	dequeue_thread_should_quit = true;
+	queues_not_empty.notify_all();
+	dequeue_thread.join();
+}
+
 void BMUSBCapture::start_bm_thread()
 {
 	should_quit = false;
diff --git a/bmusb.h b/bmusb.h
index c7a5224..96a2257 100644
--- a/bmusb.h
+++ b/bmusb.h
@@ -105,6 +105,7 @@ class BMUSBCapture {
 
 	void configure_card();
 	void start_bm_capture();
+	void stop_dequeue_thread();
 
 	static void start_bm_thread();
 	static void stop_bm_thread();
@@ -120,7 +121,7 @@ class BMUSBCapture {
 	void start_new_frame(const uint8_t *start);
 
 	void queue_frame(uint16_t format, uint16_t timecode, FrameAllocator::Frame frame, std::deque<QueuedFrame> *q);
-	void dequeue_thread();
+	void dequeue_thread_func();
 
 	static void usb_thread_func();
 	static void cb_xfr(struct libusb_transfer *xfr);
@@ -137,6 +138,8 @@ class BMUSBCapture {
 	FrameAllocator *audio_frame_allocator = nullptr;
 	frame_callback_t frame_callback = nullptr;
 
+	std::thread dequeue_thread;
+	std::atomic<bool> dequeue_thread_should_quit;
 	bool has_dequeue_callbacks = false;
 	std::function<void()> dequeue_init_callback = nullptr;
 	std::function<void()> dequeue_cleanup_callback = nullptr;
-- 
2.39.2