Merge remote-tracking branch 'origin/tracking' into custom

dom/media/ADTSDemuxer.cpp

@@ -5,12 +5,10 @@
 
 #include "ADTSDemuxer.h"
 
-#include <inttypes.h>
-
-#include "nsAutoPtr.h"
-#include "VideoUtils.h"
 #include "TimeUnits.h"
-#include "prenv.h"
+#include "VideoUtils.h"
+#include "mozilla/UniquePtr.h"
+#include <inttypes.h>
 
 #ifdef PR_LOGGING
 extern mozilla::LazyLogModule gMediaDemuxerLog;
@@ -160,11 +158,11 @@ public:
   }
 
   // Returns whether the valid
-  bool Parse(int64_t aOffset, uint8_t* aStart, uint8_t* aEnd) {
+  bool Parse(int64_t aOffset, const uint8_t* aStart, const uint8_t* aEnd) {
     MOZ_ASSERT(aStart && aEnd);
 
     bool found = false;
-    uint8_t* ptr = aStart;
+    const uint8_t* ptr = aStart;
     // Require at least 7 bytes of data at the end of the buffer for the minimum
     // ADTS frame header.
     while (ptr < aEnd - 7 && !found) {
@@ -214,7 +212,7 @@ public:
   // if one was found. After returning, the variable passed to 'aBytesToSkip' holds
   // the amount of bytes to be skipped (if any) in order to jump across a large
   // ID3v2 tag spanning multiple buffers.
-  bool Parse(int64_t aOffset, uint8_t* aStart, uint8_t* aEnd) {
+  bool Parse(int64_t aOffset, const uint8_t* aStart, const uint8_t* aEnd) {
     const bool found = mFrame.Parse(aOffset, aStart, aEnd);
 
     if (mFrame.Length() && !mFirstFrame.Length()) {
@@ -728,7 +726,7 @@ ADTSTrackDemuxer::GetNextFrame(const adts::Frame& aFrame)
   RefPtr<MediaRawData> frame = new MediaRawData();
   frame->mOffset = offset;
 
-  nsAutoPtr<MediaRawDataWriter> frameWriter(frame->CreateWriter());
+  UniquePtr<MediaRawDataWriter> frameWriter(frame->CreateWriter());
   if (!frameWriter->SetSize(length)) {
     ADTSLOG("GetNext() Exit failed to allocated media buffer");
     return nullptr;
@@ -842,4 +840,30 @@ ADTSTrackDemuxer::AverageFrameLength() const
   return 0.0;
 }
 
+/* static */ bool
+ADTSDemuxer::ADTSSniffer(const uint8_t* aData, const uint32_t aLength)
+{
+  if (aLength < 7) {
+    return false;
+  }
+  // Avoid seeking if blob doesn't start with an ADTS marker.
+  if (!adts::FrameHeader::MatchesSync(aData)) {
+    return false;
+  }
+  auto parser = MakeUnique<adts::FrameParser>();
+
+  if (!parser->Parse(0, aData, aData + aLength)) {
+    return false;
+  }
+  const adts::Frame& currentFrame = parser->CurrentFrame();
+  // Check for sync marker after the found frame, since it's
+  // possible to find sync marker in AAC data. If sync marker
+  // exists after the current frame then we've found a frame
+  // header.
+  int64_t nextFrameHeaderOffset = currentFrame.Offset() + currentFrame.Length();
+  return int64_t(aLength) > nextFrameHeaderOffset &&
+         aLength - nextFrameHeaderOffset >= 2 &&
+         adts::FrameHeader::MatchesSync(aData + nextFrameHeaderOffset);
+}
+
 } // namespace mozilla

dom/media/ADTSDemuxer.h

@@ -32,6 +32,9 @@ public:
     TrackInfo::TrackType aType, uint32_t aTrackNumber) override;
   bool IsSeekable() const override;
 
+  // Return true if a valid ADTS frame header could be found.
+  static bool ADTSSniffer(const uint8_t* aData, const uint32_t aLength);
+
 private:
   bool InitInternal();