simple_buffer.h revision 201ade2fbba22bfb27ae029f4d23fca6ded109a0 
1// Copyright (c) 2009 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_TOOLS_FLIP_SERVER_SIMPLE_BUFFER_H__
6#define NET_TOOLS_FLIP_SERVER_SIMPLE_BUFFER_H__
7#pragma once
8
9#include <string>
10
11#include "net/tools/flip_server/buffer_interface.h"
12
13namespace net {
14
15class SimpleBuffer : public BufferInterface {
16 public:
17  SimpleBuffer();
18  explicit SimpleBuffer(int size);
19  virtual ~SimpleBuffer() {
20    delete[] storage_;
21  }
22
23  std::string str() const;
24
25  typedef char * iterator;
26  typedef const char * const_iterator;
27
28  iterator begin() { return storage_ + read_idx_; }
29  const_iterator begin() const { return storage_ + read_idx_; }
30
31  iterator end() { return storage_ + write_idx_; }
32  const_iterator end() const { return storage_ + write_idx_; }
33
34  // The following functions all override pure virtual functions
35  // in BufferInterface. See buffer_interface.h for a description
36  // of what they do.
37  virtual int ReadableBytes() const;
38  virtual int BufferSize() const;
39  virtual int BytesFree() const;
40
41  virtual bool Empty() const;
42  virtual bool Full() const;
43
44  virtual int Write(const char* bytes, int size);
45
46  virtual void GetWritablePtr(char **ptr, int* size) const;
47
48  virtual void GetReadablePtr(char **ptr, int* size) const;
49
50  virtual int Read(char* bytes, int size);
51
52  virtual void Clear();
53
54  // This can be an expensive operation: costing a new/delete, and copying of
55  // all existing data. Even if the existing buffer does not need to be
56  // resized, unread data may still need to be non-destructively copied to
57  // consolidate fragmented free space.
58  virtual bool Reserve(int size);
59
60  virtual void AdvanceReadablePtr(int amount_to_advance);
61
62  virtual void AdvanceWritablePtr(int amount_to_advance);
63
64  void Swap(SimpleBuffer* other) {
65    char* tmp = storage_;
66    storage_ = other->storage_;
67    other->storage_ = tmp;
68
69    int tmp_int = write_idx_;
70    write_idx_ = other->write_idx_;
71    other->write_idx_ = tmp_int;
72
73    tmp_int = read_idx_;
74    read_idx_ = other->read_idx_;
75    other->read_idx_ = tmp_int;
76
77    tmp_int = storage_size_;
78    storage_size_ = other->storage_size_;
79    other->storage_size_ = tmp_int;
80  }
81
82 protected:
83  char* storage_;
84  int write_idx_;
85  int read_idx_;
86  int storage_size_;
87
88 private:
89  //DISALLOW_COPY_AND_ASSIGN(SimpleBuffer);
90};
91
92}  // namespace net
93
94#endif  // NET_TOOLS_FLIP_SERVER_SIMPLE_BUFFER_H__
95
96