mp4: skip 0 size trun samples

media/formats/mp4/mp4_stream_parser.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "media/formats/mp4/mp4_stream_parser.h"
 
 #include <stddef.h>
 
 #include <limits>
 #include <memory>
@@ skipping 15 matching lines @@
 #include "media/base/video_util.h"
 #include "media/formats/mp4/box_definitions.h"
 #include "media/formats/mp4/box_reader.h"
 #include "media/formats/mp4/es_descriptor.h"
 #include "media/formats/mp4/rcheck.h"
 #include "media/formats/mpeg/adts_constants.h"
 
 namespace media {
 namespace mp4 {
 
+namespace {
+const int kMaxEmptySampleLogs = 20;
+}

[wolenetz, 2016/09/23 19:14:54]

nit: // namespace

+
 MP4StreamParser::MP4StreamParser(const std::set<int>& audio_object_types,
                                  bool has_sbr)
     : state_(kWaitingForInit),
       moof_head_(0),
       mdat_tail_(0),
       highest_end_offset_(0),
       has_audio_(false),
       has_video_(false),
       audio_object_types_(audio_object_types),
       has_sbr_(has_sbr),
-      num_top_level_box_skipped_(0) {
-}
+      num_top_level_box_skipped_(0),

[wolenetz, 2016/09/23 19:14:54]

aside: this other counter is no longer used. we should remove it.

+      num_emtpy_samples_skipped_(0) {}
 
 MP4StreamParser::~MP4StreamParser() {}
 
 void MP4StreamParser::Init(
     const InitCB& init_cb,
     const NewConfigCB& config_cb,
     const NewBuffersCB& new_buffers_cb,
     bool /* ignore_text_tracks */,
     const EncryptedMediaInitDataCB& encrypted_media_init_data_cb,
     const NewMediaSegmentCB& new_segment_cb,
@@ skipping 492 matching lines @@
   if (runs_->AuxInfoNeedsToBeCached()) {
     queue_.PeekAt(runs_->aux_info_offset() + moof_head_, &buf, &buf_size);
     if (buf_size < runs_->aux_info_size()) return false;
     *err = !runs_->CacheAuxInfo(buf, buf_size);
     return !*err;
   }
 
   queue_.PeekAt(runs_->sample_offset() + moof_head_, &buf, &buf_size);
   if (buf_size < runs_->sample_size()) return false;
 
+  if (runs_->sample_size() == 0) {
+    // Generally not expected, but spec allows it. Code below this block assumes
+    // the current sample is not empty.
+    LIMITED_MEDIA_LOG(DEBUG, media_log_, num_emtpy_samples_skipped_,
+                      kMaxEmptySampleLogs)
+        << " Skipping 'trun' sample with size of 0.";
+    runs_->AdvanceSample();
+    return true;
+  }
+
   std::unique_ptr<DecryptConfig> decrypt_config;
   std::vector<SubsampleEntry> subsamples;
   if (runs_->is_encrypted()) {
     decrypt_config = runs_->GetDecryptConfig();
     if (!decrypt_config) {
       *err = true;
       return false;
     }
     subsamples = decrypt_config->subsamples();
   }
@@ skipping 134 matching lines @@
       runs.AdvanceSample();
     }
     runs.AdvanceRun();
   }
 
   return true;
 }
 
 }  // namespace mp4
 }  // namespace media