69 lines
2.2 KiB
C
69 lines
2.2 KiB
C
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// Copyright (c) 2013 Google Inc. All rights reserved.
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// Use of this source code is governed by a BSD-style license that can be
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// found in the LICENSE file.
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#ifndef MEDIA_BASE_BUFFER_READER_H_
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#define MEDIA_BASE_BUFFER_READER_H_
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#include <vector>
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#include "base/basictypes.h"
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#include "base/compiler_specific.h"
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namespace media {
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// A simple buffer reader implementation, which reads data of various type
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// from a fixed byte array.
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class BufferReader {
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public:
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BufferReader(const uint8* buf, size_t size)
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: buf_(buf), size_(size), pos_(0) {}
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~BufferReader() {}
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bool HasBytes(size_t count) { return pos() + count <= size(); }
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// Read a value from the stream, performing endian correction, and advance
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// the stream pointer.
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// Return false if there are not enough bytes in the buffer.
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bool Read1(uint8* v) WARN_UNUSED_RESULT;
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bool Read2(uint16* v) WARN_UNUSED_RESULT;
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bool Read2s(int16* v) WARN_UNUSED_RESULT;
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bool Read4(uint32* v) WARN_UNUSED_RESULT;
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bool Read4s(int32* v) WARN_UNUSED_RESULT;
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bool Read8(uint64* v) WARN_UNUSED_RESULT;
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bool Read8s(int64* v) WARN_UNUSED_RESULT;
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// Read a N-byte integer of the corresponding signedness and store it in the
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// 8-byte return type. |num_bytes| should not be larger than 8 bytes.
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// Return false if there are not enough bytes in the buffer.
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bool ReadNBytesInto8(uint64* v, size_t num_bytes) WARN_UNUSED_RESULT;
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bool ReadNBytesInto8s(int64* v, size_t num_bytes) WARN_UNUSED_RESULT;
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bool ReadToVector(std::vector<uint8>* t, size_t count) WARN_UNUSED_RESULT;
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// Advance the stream by this many bytes.
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// Return false if there are not enough bytes in the buffer.
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bool SkipBytes(size_t num_bytes) WARN_UNUSED_RESULT;
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const uint8* data() const { return buf_; }
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size_t size() const { return size_; }
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void set_size(size_t size) { size_ = size; }
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size_t pos() const { return pos_; }
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private:
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// Internal implementation of multi-byte reads.
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template <typename T>
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bool Read(T* t) WARN_UNUSED_RESULT;
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template <typename T>
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bool ReadNBytes(T* t, size_t num_bytes) WARN_UNUSED_RESULT;
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const uint8* buf_;
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size_t size_;
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size_t pos_;
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DISALLOW_COPY_AND_ASSIGN(BufferReader);
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};
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} // namespace media
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#endif // MEDIA_BASE_BUFFER_READER_H_
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