72 lines
2.2 KiB
C++
72 lines
2.2 KiB
C++
// Copyright 2014 Google Inc. All rights reserved.
|
|
//
|
|
// Use of this source code is governed by a BSD-style
|
|
// license that can be found in the LICENSE file or at
|
|
// https://developers.google.com/open-source/licenses/bsd
|
|
//
|
|
// A simple write buffer implementation, which appends various data types to
|
|
// buffer.
|
|
|
|
#ifndef MEDIA_BASE_BUFFER_WRITER_H_
|
|
#define MEDIA_BASE_BUFFER_WRITER_H_
|
|
|
|
#include <vector>
|
|
|
|
#include "base/stl_util.h"
|
|
#include "media/base/status.h"
|
|
|
|
namespace media {
|
|
|
|
class File;
|
|
|
|
class BufferWriter {
|
|
public:
|
|
BufferWriter();
|
|
// Construct the object with a reserved capacity of |reserved_size_in_bytes|.
|
|
// The value is intended for optimization and is not a hard limit. It does
|
|
// not affect the actual size of the buffer, which is still starting from 0.
|
|
explicit BufferWriter(size_t reserved_size_in_bytes);
|
|
~BufferWriter();
|
|
|
|
// These convenient functions append the integers (in network byte order,
|
|
// i.e. big endian) of various size and signedness to the end of the buffer.
|
|
void AppendInt(uint8 v);
|
|
void AppendInt(uint16 v);
|
|
void AppendInt(uint32 v);
|
|
void AppendInt(uint64 v);
|
|
void AppendInt(int16 v);
|
|
void AppendInt(int32 v);
|
|
void AppendInt(int64 v);
|
|
|
|
// Append the least significant |num_bytes| of |v| to buffer. |num_bytes|
|
|
// should not be larger than sizeof(v), i.e. 8.
|
|
void AppendNBytes(uint64 v, size_t num_bytes);
|
|
|
|
void AppendVector(const std::vector<uint8>& v);
|
|
void AppendArray(const uint8* buf, size_t size);
|
|
void AppendBuffer(const BufferWriter& buffer);
|
|
|
|
void Swap(BufferWriter* buffer) { buf_.swap(buffer->buf_); }
|
|
void Clear() { buf_.clear(); }
|
|
size_t Size() const { return buf_.size(); }
|
|
// Return underlying buffer. Return NULL if the buffer is empty.
|
|
const uint8* Buffer() const { return vector_as_array(&buf_); }
|
|
|
|
// Write the buffer to file. |file| should not be NULL.
|
|
// Returns OK on success. The internal buffer will be cleared after writing.
|
|
Status WriteToFile(File* file);
|
|
|
|
private:
|
|
// Internal implementation of multi-byte write.
|
|
template <typename T>
|
|
void AppendInternal(T v);
|
|
|
|
std::vector<uint8> buf_;
|
|
|
|
DISALLOW_COPY_AND_ASSIGN(BufferWriter);
|
|
};
|
|
|
|
} // namespace media
|
|
|
|
#endif // MEDIA_BASE_BUFFER_WRITER_H_
|