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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim:set ts=2 sw=2 sts=2 et cindent: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef BOX_H_
#define BOX_H_
#include <stdint.h>
#include "nsTArray.h"
#include "MediaResource.h"
#include "mozilla/EndianUtils.h"
#include "AtomType.h"
#include "BufferReader.h"
namespace mozilla {
class ByteStream;
class BumpAllocator {
public:
uint8_t* Allocate(size_t aNumBytes);
private:
nsTArray<nsTArray<uint8_t>> mBuffers;
};
class BoxContext {
public:
BoxContext(ByteStream* aSource, const MediaByteRangeSet& aByteRanges)
: mSource(aSource), mByteRanges(aByteRanges) {}
RefPtr<ByteStream> mSource;
const MediaByteRangeSet& mByteRanges;
BumpAllocator mAllocator;
};
struct ByteSlice {
const uint8_t* mBytes;
size_t mSize;
};
class Box {
public:
Box(BoxContext* aContext, uint64_t aOffset, const Box* aParent = nullptr);
Box();
bool IsAvailable() const { return !mRange.IsEmpty(); }
uint64_t Offset() const { return mRange.mStart; }
uint64_t Length() const { return mRange.mEnd - mRange.mStart; }
uint64_t NextOffset() const { return mRange.mEnd; }
const MediaByteRange& Range() const { return mRange; }
const Box* Parent() const { return mParent; }
bool IsType(const char* aType) const { return mType == AtomType(aType); }
Box Next() const;
Box FirstChild() const;
// Reads the box contents, excluding the header.
nsTArray<uint8_t> Read() const;
// Reads the complete box; its header and body.
nsTArray<uint8_t> ReadCompleteBox() const;
// Reads from the content of the box, excluding header.
bool Read(nsTArray<uint8_t>* aDest, const MediaByteRange& aRange) const;
static const uint64_t kMAX_BOX_READ;
// Returns a slice, pointing to the data of this box. The lifetime of
// the memory this slice points to matches the box's context's lifetime.
ByteSlice ReadAsSlice();
private:
bool Contains(MediaByteRange aRange) const;
BoxContext* mContext;
mozilla::MediaByteRange mRange;
uint64_t mBodyOffset;
uint64_t mChildOffset;
AtomType mType;
const Box* mParent;
};
// BoxReader serves box data through an AutoByteReader. The box data is
// stored either in the box's context's bump allocator, or in the ByteStream
// itself if the ByteStream implements the Access() method.
// NOTE: The data the BoxReader reads may be stored in the Box's BoxContext.
// Ensure that the BoxReader doesn't outlive the BoxContext!
class MOZ_RAII BoxReader {
public:
explicit BoxReader(Box& aBox)
: mData(aBox.ReadAsSlice()), mReader(mData.mBytes, mData.mSize) {}
BufferReader* operator->() { return &mReader; }
private:
ByteSlice mData;
BufferReader mReader;
};
} // namespace mozilla
#endif