net/curvecp/circular_buffer.h

   1 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef NET_CURVECP_CIRCULAR_BUFFER_H_
   6 #define NET_CURVECP_CIRCULAR_BUFFER_H_
   7 #pragma once
   8
   9 namespace net {
  10
  11 // A circular buffer is a fixed sized buffer which can be read or written
  12 class CircularBuffer {
  13  public:
  14   // Create a CircularBuffer with maximum size |capacity|.
  15   explicit CircularBuffer(int capacity);
  16   ~CircularBuffer();
  17
  18   int length() const { return length_; }
  19
  20   // Writes data into the circular buffer.
  21   // |data| is the bytes to write.
  22   // |length| is the number of bytes to write.
  23   // Returns the number of bytes written, which may be less than |length| or
  24   // 0 if no space is available in the buffer.
  25   int write(const char* data, int length);
  26
  27   // Reads up to |length| bytes from the buffer into |data|.
  28   // Returns the number of bytes read, or 0 if no data is available.
  29   int read(char* data, int length);
  30
  31  private:
  32   int capacity_;
  33   int head_;
  34   int length_;
  35   char* buffer_;
  36 };
  37
  38 }  // namespace net
  39
  40 #endif  //  NET_CURVECP_CIRCULAR_BUFFER_H_