From 6047352c9126f335c32dd3b845997c3260b9a617 Mon Sep 17 00:00:00 2001
From: Anthony Jones <ajones@mozilla.com>
Date: Thu, 11 Sep 2014 15:57:33 +1200
Subject: [PATCH] Bug 1061079 - Make BufferStream work for a moving window;
 r=edwin

---
 media/libstagefright/binding/BufferStream.cpp | 37 +++++++++++++++----
 media/libstagefright/binding/MoofParser.cpp   |  9 ++++-
 .../include/mp4_demuxer/BufferStream.h        | 13 +++++--
 .../binding/include/mp4_demuxer/MoofParser.h  |  3 +-
 .../binding/include/mp4_demuxer/mp4_demuxer.h |  2 +
 5 files changed, 51 insertions(+), 13 deletions(-)

diff --git a/media/libstagefright/binding/BufferStream.cpp b/media/libstagefright/binding/BufferStream.cpp
index 80107b2a073d..6b78321b4bde 100644
--- a/media/libstagefright/binding/BufferStream.cpp
+++ b/media/libstagefright/binding/BufferStream.cpp
@@ -3,33 +3,56 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 #include "mp4_demuxer/BufferStream.h"
+#include "MediaResource.h"
 #include <algorithm>
 
+using namespace mozilla;
+
 namespace mp4_demuxer {
 
-BufferStream::BufferStream(const uint8_t* aData, size_t aLength)
-  : mData(aData), mLength(aLength)
+BufferStream::BufferStream()
+  : mStartOffset(0)
 {
-
 }
 
 /*virtual*/ bool
 BufferStream::ReadAt(int64_t aOffset, void* aData, size_t aLength,
                      size_t* aBytesRead)
 {
-  if (aOffset > mLength) {
+  if (aOffset < mStartOffset || aOffset > mStartOffset + mData.Length()) {
     return false;
   }
-  *aBytesRead = std::min(aLength, mLength - (size_t) aOffset);
-  memcpy(aData, mData + aOffset, *aBytesRead);
+  *aBytesRead =
+    std::min(aLength, size_t(mStartOffset + mData.Length() - aOffset));
+  memcpy(aData, &mData[aOffset - mStartOffset], *aBytesRead);
   return true;
 }
 
 /*virtual*/ bool
 BufferStream::Length(int64_t* aLength)
 {
-  *aLength = mLength;
+  *aLength = mStartOffset + mData.Length();
   return true;
 }
 
+/* virtual */ void
+BufferStream::DiscardBefore(int64_t aOffset)
+{
+  if (aOffset > mStartOffset) {
+    mData.RemoveElementsAt(0, aOffset - mStartOffset);
+    mStartOffset = aOffset;
+  }
+}
+
+void
+BufferStream::AppendBytes(const uint8_t* aData, size_t aLength)
+{
+  mData.AppendElements(aData, aLength);
+}
+
+MediaByteRange
+BufferStream::GetByteRange()
+{
+  return MediaByteRange(mStartOffset, mStartOffset + mData.Length());
+}
 }
diff --git a/media/libstagefright/binding/MoofParser.cpp b/media/libstagefright/binding/MoofParser.cpp
index a71dc3c7282e..520f3a183532 100644
--- a/media/libstagefright/binding/MoofParser.cpp
+++ b/media/libstagefright/binding/MoofParser.cpp
@@ -37,11 +37,16 @@ MoofParser::RebuildFragmentedIndex(const nsTArray<MediaByteRange>& aByteRanges)
 }
 
 Interval<Microseconds>
-MoofParser::GetCompositionRange()
+MoofParser::GetCompositionRange(const nsTArray<MediaByteRange>& aByteRanges)
 {
   Interval<Microseconds> compositionRange;
+  BoxContext context(mSource, aByteRanges);
   for (size_t i = 0; i < mMoofs.Length(); i++) {
-    compositionRange = compositionRange.Extents(mMoofs[i].mTimeRange);
+    Moof& moof = mMoofs[i];
+    Box box(&context, moof.mRange.mStart);
+    if (box.IsAvailable()) {
+      compositionRange = compositionRange.Extents(moof.mTimeRange);
+    }
   }
   return compositionRange;
 }
diff --git a/media/libstagefright/binding/include/mp4_demuxer/BufferStream.h b/media/libstagefright/binding/include/mp4_demuxer/BufferStream.h
index d8a9bb6307a1..e54a88135e3d 100644
--- a/media/libstagefright/binding/include/mp4_demuxer/BufferStream.h
+++ b/media/libstagefright/binding/include/mp4_demuxer/BufferStream.h
@@ -6,6 +6,7 @@
 #define BUFFER_STREAM_H_
 
 #include "mp4_demuxer/mp4_demuxer.h"
+#include "nsTArray.h"
 
 namespace mp4_demuxer {
 
@@ -15,15 +16,21 @@ public:
   /* BufferStream does not take ownership of aData nor does it make a copy.
    * Therefore BufferStream shouldn't get used after aData is destroyed.
    */
-  BufferStream(const uint8_t* aData, size_t aLength);
+  BufferStream();
 
   virtual bool ReadAt(int64_t aOffset, void* aData, size_t aLength,
                       size_t* aBytesRead) MOZ_OVERRIDE;
   virtual bool Length(int64_t* aLength) MOZ_OVERRIDE;
 
+  virtual void DiscardBefore(int64_t aOffset) MOZ_OVERRIDE;
+
+  void AppendBytes(const uint8_t* aData, size_t aLength);
+
+  mozilla::MediaByteRange GetByteRange();
+
 private:
-  const uint8_t* mData;
-  size_t mLength;
+  int64_t mStartOffset;
+  nsTArray<uint8_t> mData;
 };
 }
 
diff --git a/media/libstagefright/binding/include/mp4_demuxer/MoofParser.h b/media/libstagefright/binding/include/mp4_demuxer/MoofParser.h
index 1d06718a926f..629c0750ef6f 100644
--- a/media/libstagefright/binding/include/mp4_demuxer/MoofParser.h
+++ b/media/libstagefright/binding/include/mp4_demuxer/MoofParser.h
@@ -131,7 +131,8 @@ public:
   }
   void RebuildFragmentedIndex(
     const nsTArray<mozilla::MediaByteRange>& aByteRanges);
-  Interval<Microseconds> GetCompositionRange();
+  Interval<Microseconds> GetCompositionRange(
+    const nsTArray<mozilla::MediaByteRange>& aByteRanges);
   bool ReachedEnd();
   void ParseMoov(Box& aBox);
   void ParseTrak(Box& aBox);
diff --git a/media/libstagefright/binding/include/mp4_demuxer/mp4_demuxer.h b/media/libstagefright/binding/include/mp4_demuxer/mp4_demuxer.h
index dfa21243229e..dfdca6d1d4e3 100644
--- a/media/libstagefright/binding/include/mp4_demuxer/mp4_demuxer.h
+++ b/media/libstagefright/binding/include/mp4_demuxer/mp4_demuxer.h
@@ -28,6 +28,8 @@ public:
                       size_t* bytes_read) = 0;
   virtual bool Length(int64_t* size) = 0;
 
+  virtual void DiscardBefore(int64_t offset) {}
+
 protected:
   virtual ~Stream() {}
 };