Report WOULD_BLOCK if buffer is non-empty instead of ERROR_IO

Bug: 17423087
Change-Id: I4b1c5ead919649be3b820f63a030acac729fb06e

proprietary/wvm/WVMMediaSource.cpp

@@ -202,21 +202,13 @@ std::string usecToNPT(int64_t time)
 status_t WVMMediaSource::read(MediaBuffer **buffer, const ReadOptions *options)
 {
     Mutex::Autolock autoLock(mLock);
+    //ALOGD("WVMMediaSource::read %s", (mESSelector == WV_EsSelector_Video) ? "video" : "audio");
 
     CHECK(mStarted);
 
     *buffer = NULL;
     bool seekNextSync = false;
 
-#if 0
-    // The sync bits aren't working right yet on live streams, so need to disable this
-    // for now.
-    if (mIsLiveStream && mNewSegment && (mESSelector == WV_EsSelector_Video)) {
-        seekNextSync = true;
-        mNewSegment = false;
-    }
-#endif
-
     int64_t seekTimeUs;
 
     int retryLimit = 500;  // Limit on number of retries before timeout, 10ms per retry
@@ -340,6 +332,21 @@ status_t WVMMediaSource::read(MediaBuffer **buffer, const ReadOptions *options)
                 // If no data received within the retry limit, return ERROR_IO
                 // This prevents the player from becoming unresponsive
                 mediaBuf->release();
+
+                float secondsBuffered = 0.0;
+                unsigned long bandwidth = 0;
+                WV_Info_TimeBuffered(mSession, &secondsBuffered);
+                WV_Info_CurrentBandwidth(mSession, &bandwidth);
+                ALOGI("Retry count exhausted: secondsBuffered=%5.2f, bandwidth=%ld",
+                      secondsBuffered, bandwidth);
+
+                if (secondsBuffered > 2.0) {
+                    // If there's some data buffered but no packets are for
+                    // this track, the buffer may be full of data for another track
+                    // with no room to demux in more packets. Return the non-blocking
+                    // result in this case.
+                    return WOULD_BLOCK;
+                }
                 return ERROR_IO;
             } else {
                 // Didn't get anything, sleep a bit so we don't hog the CPU then try again