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
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
|
/*
* gitg-hash.c
* This file is part of gitg - git repository viewer
*
* Copyright (C) 2009 - Jesse van den Kieboom
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330,
* Boston, MA 02111-1307, USA.
*/
#include <string.h>
#include <glib.h>
#include <stdlib.h>
#include <math.h>
#include "gitg-hash.h"
inline static guint8
atoh (gchar c)
{
if (c >= 'a')
{
return c - 'a' + 10;
}
if (c >= 'A')
{
return c - 'A' + 10;
}
return c - '0';
}
void
gitg_hash_partial_sha1_to_hash (gchar const *sha,
gint length,
gchar *hash)
{
if (length % 2 == 1)
{
--length;
}
int i;
for (i = 0; i < length / 2; ++i)
{
gchar h = atoh (*(sha++)) << 4;
hash[i] = h | atoh (*(sha++));
}
}
void
gitg_hash_sha1_to_hash (gchar const *sha,
gchar *hash)
{
gitg_hash_partial_sha1_to_hash (sha, GITG_HASH_SHA_SIZE, hash);
}
void
gitg_hash_hash_to_sha1 (gchar const *hash,
gchar *sha)
{
char const *repr = "0123456789abcdef";
int i;
int pos = 0;
for (i = 0; i < GITG_HASH_BINARY_SIZE; ++i)
{
sha[pos++] = repr[(hash[i] >> 4) & 0x0f];
sha[pos++] = repr[(hash[i] & 0x0f)];
}
}
gchar *
gitg_hash_hash_to_sha1_new (gchar const *hash)
{
gchar *ret = g_new (gchar, GITG_HASH_SHA_SIZE + 1);
gitg_hash_hash_to_sha1 (hash, ret);
ret[GITG_HASH_SHA_SIZE] = '\0';
return ret;
}
gchar *
gitg_hash_partial_sha1_to_hash_new (gchar const *sha,
gint length,
gint *retlen)
{
if (length == -1)
{
length = strlen (sha);
}
if (length % 2 != 0)
{
--length;
}
*retlen = length / 2;
gchar *ret = g_new (gchar, *retlen);
gitg_hash_partial_sha1_to_hash (sha, length, ret);
return ret;
}
gchar *
gitg_hash_sha1_to_hash_new (gchar const *sha1)
{
gchar *ret = g_new (gchar, GITG_HASH_BINARY_SIZE);
gitg_hash_sha1_to_hash (sha1, ret);
return ret;
}
guint
gitg_hash_hash (gconstpointer v)
{
/* 31 bit hash function, copied from g_str_hash */
const signed char *p = v;
guint32 h = *p;
int i;
for (i = 1; i < GITG_HASH_BINARY_SIZE; ++i)
h = (h << 5) - h + p[i];
return h;
}
gboolean
gitg_hash_hash_equal (gconstpointer a, gconstpointer b)
{
return memcmp (a, b, GITG_HASH_BINARY_SIZE) == 0;
}
|
