third_party/grpc/include/grpc++/support/byte_buffer.h

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#ifndef GRPCXX_SUPPORT_BYTE_BUFFER_H
#define GRPCXX_SUPPORT_BYTE_BUFFER_H

#include <grpc/grpc.h>
#include <grpc/byte_buffer.h>
#include <grpc/support/log.h>
#include <grpc++/impl/serialization_traits.h>
#include <grpc++/support/config.h>
#include <grpc++/support/slice.h>
#include <grpc++/support/status.h>

#include <vector>

namespace grpc {

/// A sequence of bytes.
class ByteBuffer GRPC_FINAL {
 public:
  /// Constuct an empty buffer.
  ByteBuffer() : buffer_(nullptr) {}

  /// Construct buffer from \a slices, of which there are \a nslices.
  ByteBuffer(const Slice* slices, size_t nslices);

  /// Constuct a byte buffer by referencing elements of existing buffer
  /// \a buf. Wrapper of core function grpc_byte_buffer_copy
  ByteBuffer(const ByteBuffer& buf);

  ~ByteBuffer();

  ByteBuffer& operator=(const ByteBuffer&);

  /// Dump (read) the buffer contents into \a slices.
  void Dump(std::vector<Slice>* slices) const;

  /// Remove all data.
  void Clear();

  /// Buffer size in bytes.
  size_t Length() const;

 private:
  friend class SerializationTraits<ByteBuffer, void>;

  // takes ownership
  void set_buffer(grpc_byte_buffer* buf) {
    if (buffer_) {
      Clear();
    }
    buffer_ = buf;
  }

  // For \a SerializationTraits's usage.
  grpc_byte_buffer* buffer() const { return buffer_; }

  grpc_byte_buffer* buffer_;
};

template <>
class SerializationTraits<ByteBuffer, void> {
 public:
  static Status Deserialize(grpc_byte_buffer* byte_buffer, ByteBuffer* dest,
                            int max_message_size) {
    dest->set_buffer(byte_buffer);
    return Status::OK;
  }
  static Status Serialize(const ByteBuffer& source, grpc_byte_buffer** buffer,
                          bool* own_buffer) {
    *buffer = source.buffer();
    *own_buffer = false;
    return Status::OK;
  }
};

}  // namespace grpc

#endif  // GRPCXX_SUPPORT_BYTE_BUFFER_H