index.h revision 213700 
1///////////////////////////////////////////////////////////////////////////////
2//
3/// \file       index.h
4/// \brief      Handling of Index
5//
6//  Author:     Lasse Collin
7//
8//  This file has been put into the public domain.
9//  You can do whatever you want with this file.
10//
11///////////////////////////////////////////////////////////////////////////////
12
13#ifndef LZMA_INDEX_H
14#define LZMA_INDEX_H
15
16#include "common.h"
17
18
19/// Minimum Unpadded Size
20#define UNPADDED_SIZE_MIN LZMA_VLI_C(5)
21
22/// Maximum Unpadded Size
23#define UNPADDED_SIZE_MAX (LZMA_VLI_MAX & ~LZMA_VLI_C(3))
24
25
26/// Get the size of the Index Padding field. This is needed by Index encoder
27/// and decoder, but applications should have no use for this.
28extern uint32_t lzma_index_padding_size(const lzma_index *i);
29
30
31/// Set for how many Records to allocate memory the next time
32/// lzma_index_append() needs to allocate space for a new Record.
33/// This is used only by the Index decoder.
34extern void lzma_index_prealloc(lzma_index *i, lzma_vli records);
35
36
37/// Round the variable-length integer to the next multiple of four.
38static inline lzma_vli
39vli_ceil4(lzma_vli vli)
40{
41	assert(vli <= LZMA_VLI_MAX);
42	return (vli + 3) & ~LZMA_VLI_C(3);
43}
44
45
46/// Calculate the size of the Index field excluding Index Padding
47static inline lzma_vli
48index_size_unpadded(lzma_vli count, lzma_vli index_list_size)
49{
50	// Index Indicator + Number of Records + List of Records + CRC32
51	return 1 + lzma_vli_size(count) + index_list_size + 4;
52}
53
54
55/// Calculate the size of the Index field including Index Padding
56static inline lzma_vli
57index_size(lzma_vli count, lzma_vli index_list_size)
58{
59	return vli_ceil4(index_size_unpadded(count, index_list_size));
60}
61
62
63/// Calculate the total size of the Stream
64static inline lzma_vli
65index_stream_size(lzma_vli blocks_size,
66		lzma_vli count, lzma_vli index_list_size)
67{
68	return LZMA_STREAM_HEADER_SIZE + blocks_size
69			+ index_size(count, index_list_size)
70			+ LZMA_STREAM_HEADER_SIZE;
71}
72
73#endif
74