Cast: Cleaning up static_casts

Changed to use size_t through out the code to avoid 
static_casts. Also added a few DCHECKs in the locations 
where we really downcast to a smaller size.

Review URL: https://codereview.chromium.org/26253007

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@229909 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 22 insertions, 5 deletions

diff --git a/media/cast/video_sender/video_sender.cc b/media/cast/video_sender/video_sender.cc
index 10d83ce..52fa3e2 100644
--- a/media/cast/video_sender/video_sender.cc
+++ b/media/cast/video_sender/video_sender.cc
@@ -96,7 +96,7 @@ VideoSender::VideoSender(
   max_unacked_frames_ = static_cast<uint8>(video_config.rtp_max_delay_ms *
       video_config.max_frame_rate / 1000) + 1;
   VLOG(1) << "max_unacked_frames " << static_cast<int>(max_unacked_frames_);
-  DCHECK(max_unacked_frames_ > 0) << "Invalid argument";
+  DCHECK_GT(max_unacked_frames_, 0) << "Invalid argument";
 
   rtp_video_sender_statistics_.reset(
       new LocalRtpVideoSenderStatistics(rtp_sender_.get()));
@@ -174,6 +174,9 @@ void VideoSender::SendEncodedVideoFrame(const EncodedVideoFrame* encoded_frame,
 
 void VideoSender::OnReceivedIntraFrameRequest() {
   if (last_sent_key_frame_id_ != -1) {
+    DCHECK_GE(255, last_sent_key_frame_id_);
+    DCHECK_LE(0, last_sent_key_frame_id_);
+
     uint8 frames_in_flight = static_cast<uint8>(last_sent_frame_id_) -
                              static_cast<uint8>(last_sent_key_frame_id_);
     if (frames_in_flight < (max_unacked_frames_ - 1)) return;
@@ -183,7 +186,7 @@ void VideoSender::OnReceivedIntraFrameRequest() {
   last_sent_frame_id_ = -1;
 }
 
-void VideoSender::IncomingRtcpPacket(const uint8* packet, int length,
+void VideoSender::IncomingRtcpPacket(const uint8* packet, size_t length,
                                      const base::Closure callback) {
   rtcp_->IncomingRtcpPacket(packet, length);
   cast_environment_->PostTask(CastEnvironment::MAIN, FROM_HERE, callback);
@@ -234,6 +237,9 @@ void VideoSender::ResendCheck() {
         last_sent_frame_id_ = -1;
         UpdateFramesInFlight();
       } else {
+        DCHECK_GE(255, last_acked_frame_id_);
+        DCHECK_LE(0, last_acked_frame_id_);
+
         uint8 frame_id = static_cast<uint8>(last_acked_frame_id_ + 1);
         VLOG(1) << "ACK timeout resend frame:" << static_cast<int>(frame_id);
         ResendFrame(frame_id);
@@ -312,6 +318,8 @@ void VideoSender::OnReceivedCastFeedback(const RtcpCastMessage& cast_feedback) {
       resend_frame = static_cast<uint8>(last_acked_frame_id_ + 1);
     }
     if (resend_frame != -1) {
+      DCHECK_GE(255, resend_frame);
+      DCHECK_LE(0, resend_frame);
       VLOG(1) << "Received duplicate ACK for frame:"
               << static_cast<int>(resend_frame);
       ResendFrame(static_cast<uint8>(resend_frame));
@@ -336,8 +344,17 @@ void VideoSender::ReceivedAck(uint8 acked_frame_id) {
 
 void VideoSender::UpdateFramesInFlight() {
   if (last_sent_frame_id_ != -1) {
-    uint8 frames_in_flight = static_cast<uint8>(last_sent_frame_id_) -
-                             static_cast<uint8>(last_acked_frame_id_);
+    DCHECK_GE(255, last_sent_frame_id_);
+    DCHECK_LE(0, last_sent_frame_id_);
+    uint8 frames_in_flight;
+    if (last_acked_frame_id_ != -1) {
+      DCHECK_GE(255, last_acked_frame_id_);
+      DCHECK_LE(0, last_acked_frame_id_);
+      frames_in_flight = static_cast<uint8>(last_sent_frame_id_) -
+                         static_cast<uint8>(last_acked_frame_id_);
+    } else {
+      frames_in_flight = last_sent_frame_id_ + 1;
+    }
     VLOG(1) << "Frames in flight; last sent: " << last_sent_frame_id_
             << " last acked:" << last_acked_frame_id_;
     if (frames_in_flight >= max_unacked_frames_) {
diff --git a/media/cast/video_sender/video_sender.h b/media/cast/video_sender/video_sender.h
index 6e86645..7bd6029 100644
--- a/media/cast/video_sender/video_sender.h
+++ b/media/cast/video_sender/video_sender.h
@@ -61,7 +61,7 @@ class VideoSender : public base::NonThreadSafe,
                              const base::Closure callback);
 
   // Only called from the main cast thread.
-  void IncomingRtcpPacket(const uint8* packet, int length,
+  void IncomingRtcpPacket(const uint8* packet, size_t length,
                           const base::Closure callback);
 
  protected: