1/*
2 * libjingle
3 * Copyright 2012, Google, Inc.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are met:
7 *
8 *  1. Redistributions of source code must retain the above copyright notice,
9 *     this list of conditions and the following disclaimer.
10 *  2. Redistributions in binary form must reproduce the above copyright notice,
11 *     this list of conditions and the following disclaimer in the documentation
12 *     and/or other materials provided with the distribution.
13 *  3. The name of the author may not be used to endorse or promote products
14 *     derived from this software without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
17 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
18 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
19 * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
20 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
21 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
22 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
23 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
24 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
25 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
27
28#ifndef TALK_BASE_CRC32_H_
29#define TALK_BASE_CRC32_H_
30
31#include <string>
32
33#include "talk/base/basictypes.h"
34
35namespace talk_base {
36
37// Updates a CRC32 checksum with |len| bytes from |buf|. |initial| holds the
38// checksum result from the previous update; for the first call, it should be 0.
39uint32 UpdateCrc32(uint32 initial, const void* buf, size_t len);
40
41// Computes a CRC32 checksum using |len| bytes from |buf|.
42inline uint32 ComputeCrc32(const void* buf, size_t len) {
43  return UpdateCrc32(0, buf, len);
44}
45inline uint32 ComputeCrc32(const std::string& str) {
46  return ComputeCrc32(str.c_str(), str.size());
47}
48
49}  // namespace talk_base
50
51#endif  // TALK_BASE_CRC32_H_
52