Fix shutdown race for ViEEncoder when there is a frame in the encoder.

There is a potential race when deleting a channel and there is a frame
in the encoder. ViEEncoder::SendData can be called after
ViEEncoder::StopThreadsAndRemovePayloadRouter and payload_router is
then already removed.

Until we have the new API in place, use scoped_refptr in ViEChannel and
ViEEncoder and deregister channel/encoder before deleting.

BUG=769
R=stefan@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/42019004

Cr-Commit-Position: refs/heads/master@{#8443}
git-svn-id: http://webrtc.googlecode.com/svn/trunk@8443 4adac7df-926f-26a2-2b94-8c16560cd09d

webrtc/video_engine/payload_router.h

@@ -17,6 +17,7 @@
 #include "webrtc/base/constructormagic.h"
 #include "webrtc/base/thread_annotations.h"
 #include "webrtc/common_types.h"
+#include "webrtc/system_wrappers/interface/atomic32.h"
 #include "webrtc/system_wrappers/interface/scoped_ptr.h"
 
 namespace webrtc {
@@ -68,6 +69,9 @@ class PayloadRouter {
   // and RTP headers.
   size_t MaxPayloadLength() const;
 
+  void AddRef() { ++ref_count_; }
+  void Release() { if (--ref_count_ == 0) { delete this; } }
+
  private:
   // TODO(mflodman): When the new video API has launched, remove crit_ and
   // assume rtp_modules_ will never change during a call.
@@ -77,6 +81,8 @@ class PayloadRouter {
   std::vector<RtpRtcp*> rtp_modules_ GUARDED_BY(crit_.get());
   bool active_ GUARDED_BY(crit_.get());
 
+  Atomic32 ref_count_;
+
   DISALLOW_COPY_AND_ASSIGN(PayloadRouter);
 };
 

webrtc/video_engine/vie_channel.cc

@@ -1509,8 +1509,8 @@ RtpRtcp* ViEChannel::rtp_rtcp() {
   return rtp_rtcp_.get();
 }
 
-PayloadRouter* ViEChannel::send_payload_router() {
+scoped_refptr<PayloadRouter> ViEChannel::send_payload_router() {
-  return send_payload_router_.get();
+  return send_payload_router_;
 }
 
 CallStatsObserver* ViEChannel::GetStatsObserver() {

webrtc/video_engine/vie_channel.h

@@ -19,6 +19,7 @@
 #include "webrtc/modules/video_coding/main/interface/video_coding_defines.h"
 #include "webrtc/system_wrappers/interface/critical_section_wrapper.h"
 #include "webrtc/system_wrappers/interface/scoped_ptr.h"
+#include "webrtc/system_wrappers/interface/scoped_refptr.h"
 #include "webrtc/system_wrappers/interface/tick_util.h"
 #include "webrtc/typedefs.h"
 #include "webrtc/video_engine/include/vie_network.h"
@@ -303,7 +304,7 @@ class ViEChannel
 
   // Gets the modules used by the channel.
   RtpRtcp* rtp_rtcp();
-  PayloadRouter* send_payload_router();
+  scoped_refptr<PayloadRouter> send_payload_router();
 
   CallStatsObserver* GetStatsObserver();
 
@@ -495,7 +496,7 @@ class ViEChannel
   scoped_ptr<RtpRtcp> rtp_rtcp_;
   std::list<RtpRtcp*> simulcast_rtp_rtcp_;
   std::list<RtpRtcp*> removed_rtp_rtcp_;
-  scoped_ptr<PayloadRouter> send_payload_router_;
+  scoped_refptr<PayloadRouter> send_payload_router_;
 
   VideoCodingModule* const vcm_;
   ViEReceiver vie_receiver_;

webrtc/video_engine/vie_channel_manager.cc

@@ -20,6 +20,7 @@
 #include "webrtc/system_wrappers/interface/logging.h"
 #include "webrtc/video_engine/call_stats.h"
 #include "webrtc/video_engine/encoder_state_feedback.h"
+#include "webrtc/video_engine/payload_router.h"
 #include "webrtc/video_engine/vie_channel.h"
 #include "webrtc/video_engine/vie_defines.h"
 #include "webrtc/video_engine/vie_encoder.h"

webrtc/video_engine/vie_encoder.cc

@@ -229,7 +229,7 @@ bool ViEEncoder::Init() {
 }
 
 void ViEEncoder::StartThreadsAndSetSendPayloadRouter(
-    PayloadRouter* send_payload_router) {
+    scoped_refptr<PayloadRouter> send_payload_router) {
   DCHECK(send_payload_router_ == NULL);
   send_payload_router_ = send_payload_router;
 
@@ -245,7 +245,6 @@ void ViEEncoder::StopThreadsAndRemovePayloadRouter() {
   module_process_thread_.DeRegisterModule(&vcm_);
   module_process_thread_.DeRegisterModule(&vpm_);
   module_process_thread_.DeRegisterModule(default_rtp_rtcp_.get());
-  send_payload_router_ = nullptr;
 }
 
 ViEEncoder::~ViEEncoder() {

webrtc/video_engine/vie_encoder.h

@@ -24,6 +24,7 @@
 #include "webrtc/modules/video_processing/main/interface/video_processing.h"
 #include "webrtc/typedefs.h"
 #include "webrtc/frame_callback.h"
+#include "webrtc/system_wrappers/interface/scoped_refptr.h"
 #include "webrtc/video_engine/vie_defines.h"
 #include "webrtc/video_engine/vie_frame_provider_base.h"
 
@@ -69,7 +70,8 @@ class ViEEncoder
   // only once.
   // Ideally this would be done in Init, but the dependencies between ViEEncoder
   // and ViEChannel makes it really hard to do in a good way.
-  void StartThreadsAndSetSendPayloadRouter(PayloadRouter* send_payload_router);
+  void StartThreadsAndSetSendPayloadRouter(
+      scoped_refptr<PayloadRouter> send_payload_router);
 
   // This function must be called before the corresponding ViEChannel is
   // deleted.
@@ -215,7 +217,7 @@ class ViEEncoder
   VideoCodingModule& vcm_;
   VideoProcessingModule& vpm_;
   rtc::scoped_ptr<RtpRtcp> default_rtp_rtcp_;
-  PayloadRouter* send_payload_router_;
+  scoped_refptr<PayloadRouter> send_payload_router_;
   rtc::scoped_ptr<CriticalSectionWrapper> callback_cs_;
   rtc::scoped_ptr<CriticalSectionWrapper> data_cs_;
   rtc::scoped_ptr<BitrateObserver> bitrate_observer_;