1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
|
/* SPDX-License-Identifier: GPL-3.0-or-later */
#include "config.h"
#include "fstree.h"
#include <string.h>
file_info_t *fragment_by_chksum(file_info_t *fi, uint32_t chksum,
size_t frag_size, file_info_t *list,
size_t block_size)
{
file_info_t *it;
for (it = list; it != NULL; it = it->next) {
if (it == fi) {
it = NULL;
break;
}
if (!(it->flags & FILE_FLAG_HAS_FRAGMENT))
continue;
if (it->flags & FILE_FLAG_FRAGMENT_IS_DUPLICATE)
continue;
if ((it->size % block_size) != frag_size)
continue;
if (it->fragment_chksum == chksum)
break;
}
return it;
}
static size_t get_block_count(file_info_t *fi, size_t block_size)
{
size_t count = fi->size / block_size;
if ((fi->size % block_size) && !(fi->flags & FILE_FLAG_HAS_FRAGMENT))
++count;
while (count > 0 && fi->blocks[count - 1].size == 0)
--count;
return count;
}
static size_t find_first_match(file_info_t *file, file_info_t *cmp,
size_t idx, size_t cmp_blk_count)
{
size_t i;
for (i = 0; i < cmp_blk_count; ++i) {
if (memcmp(file->blocks + idx, cmp->blocks + i,
sizeof(file->blocks[idx])) == 0) {
break;
}
}
return i;
}
uint64_t find_equal_blocks(file_info_t *file, file_info_t *list,
size_t block_size)
{
size_t start, first_match, i, j, block_count, cmp_blk_count;
uint64_t location;
file_info_t *it;
block_count = get_block_count(file, block_size);
if (block_count == 0)
return 0;
for (start = 0; start < block_count; ++start) {
if (file->blocks[start].size != 0)
break;
}
for (it = list; it != NULL; it = it->next) {
if (it == file) {
it = NULL;
break;
}
if (it->flags & FILE_FLAG_BLOCKS_ARE_DUPLICATE)
continue;
cmp_blk_count = get_block_count(it, block_size);
if (cmp_blk_count == 0)
continue;
first_match = find_first_match(file, it, start, cmp_blk_count);
if (first_match == cmp_blk_count)
continue;
i = start;
j = first_match;
while (i < block_count && j < cmp_blk_count) {
if (file->blocks[i].size == 0) {
++i;
continue;
}
if (it->blocks[j].size == 0) {
++j;
continue;
}
if (memcmp(it->blocks + j, file->blocks + i,
sizeof(file->blocks[i])) != 0) {
break;
}
++i;
++j;
}
if (i == block_count)
break;
}
if (it == NULL)
return 0;
location = it->startblock;
for (i = 0; i < first_match; ++i)
location += it->blocks[i].size & ((1 << 24) - 1);
return location;
}
|
