1/*-
2 * Copyright 2003,2004 Colin Percival
3 * All rights reserved
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted providing that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
16 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
18 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
22 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
23 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
24 * POSSIBILITY OF SUCH DAMAGE.
25 *
26 * Changelog:
27 * 2005-04-26 - Define the header as a C structure, add a CRC32 checksum to
28 *              the header, and make all the types 32-bit.
29 *                --Benjamin Smedberg <benjamin@smedbergs.us>
30 * 2009-03-31 - Change to use Streams.  Move CRC code to crc.{h,cc}
31 *              Changed status to an enum, removed unused status codes.
32 *                --Stephen Adams <sra@chromium.org>
33 * 2013-04-10 - Added wrapper to apply a patch directly to files.
34 *                --Joshua Pawlicki <waffles@chromium.org>
35 */
36
37#ifndef COURGETTE_BSDIFF_H_
38#define COURGETTE_BSDIFF_H_
39
40#include "base/basictypes.h"
41#include "base/files/file_util.h"
42
43namespace courgette {
44
45enum BSDiffStatus {
46  OK = 0,
47  MEM_ERROR = 1,
48  CRC_ERROR = 2,
49  READ_ERROR = 3,
50  UNEXPECTED_ERROR = 4,
51  WRITE_ERROR = 5
52};
53
54class SourceStream;
55class SinkStream;
56
57// Creates a binary patch.
58//
59BSDiffStatus CreateBinaryPatch(SourceStream* old_stream,
60                               SourceStream* new_stream,
61                               SinkStream* patch_stream);
62
63// Applies the given patch file to a given source file. This method validates
64// the CRC of the original file stored in the patch file, before applying the
65// patch to it.
66//
67BSDiffStatus ApplyBinaryPatch(SourceStream* old_stream,
68                              SourceStream* patch_stream,
69                              SinkStream* new_stream);
70
71// As above, but simply takes the file paths.
72BSDiffStatus ApplyBinaryPatch(const base::FilePath& old_stream,
73                              const base::FilePath& patch_stream,
74                              const base::FilePath& new_stream);
75
76// The following declarations are common to the patch-creation and
77// patch-application code.
78
79// The patch stream starts with a MBSPatchHeader.
80typedef struct MBSPatchHeader_ {
81  char tag[8];       // Contains MBS_PATCH_HEADER_TAG
82  uint32 slen;       // Length of the file to be patched.
83  uint32 scrc32;     // CRC32 of the file to be patched.
84  uint32 dlen;       // Length of the result file.
85} MBSPatchHeader;
86
87// This is the value for the tag field.  Must match length exactly, not counting
88// null at end of string.
89#define MBS_PATCH_HEADER_TAG "GBSDIF42"
90
91}  // namespace
92#endif  // COURGETTE_BSDIFF_H_
93