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
148
149
150
151
152
153
154
155
156
157
| | /* hex-escape.c - Manage encoding and decoding of byte strings into path names
*
* Copyright (c) 2011 David Bremner
*
* 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 3 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, see http://www.gnu.org/licenses/ .
*
* Author: David Bremner <david@tethera.net>
*/
#include <assert.h>
#include <string.h>
#include <talloc.h>
#include <ctype.h>
#include "error_util.h"
#include "hex-escape.h"
static const size_t default_buf_size = 1024;
static const char *output_charset =
"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+-_@=.:,";
static const int escape_char = '%';
static int
is_output (char c)
{
return (strchr (output_charset, c) != NULL);
}
static int
maybe_realloc (void *ctx, size_t needed, char **out, size_t *out_size)
{
if (*out_size < needed) {
if (*out == NULL)
*out = talloc_size (ctx, needed);
else
*out = talloc_realloc (ctx, *out, char, needed);
if (*out == NULL)
return 0;
*out_size = needed;
}
return 1;
}
hex_status_t
hex_encode (void *ctx, const char *in, char **out, size_t *out_size)
{
const unsigned char *p;
char *q;
size_t escape_count = 0;
size_t len = 0;
size_t needed;
assert (ctx); assert (in); assert (out); assert (out_size);
for (p = (unsigned char *) in; *p; p++) {
escape_count += (!is_output (*p));
len++;
}
needed = len + escape_count * 2 + 1;
if (*out == NULL)
*out_size = 0;
if (!maybe_realloc (ctx, needed, out, out_size))
return HEX_OUT_OF_MEMORY;
q = *out;
p = (unsigned char *) in;
while (*p) {
if (is_output (*p)) {
*q++ = *p++;
} else {
sprintf (q, "%%%02x", *p++);
q += 3;
}
}
*q = '\0';
return HEX_SUCCESS;
}
hex_status_t
hex_decode (void *ctx, const char *in, char **out, size_t * out_size)
{
char buf[3];
const char *p;
unsigned char *q;
size_t escape_count = 0;
size_t needed = 0;
assert (ctx); assert (in); assert (out); assert (out_size);
size_t len = strlen (in);
for (p = in; *p; p++)
escape_count += (*p == escape_char);
needed = len - escape_count * 2 + 1;
if (!maybe_realloc (ctx, needed, out, out_size))
return HEX_OUT_OF_MEMORY;
p = in;
q = (unsigned char *) *out;
buf[2] = 0;
while (*p) {
if (*p == escape_char) {
char *endp;
if (!isxdigit ((unsigned char) p[1]) ||
!isxdigit ((unsigned char) p[2]))
return HEX_SYNTAX_ERROR;
buf[0] = p[1];
buf[1] = p[2];
*q = strtoul (buf, &endp, 16);
if (endp != buf + 2)
return HEX_SYNTAX_ERROR;
p += 3;
q++;
} else {
*q++ = *p++;
}
}
*q = '\0';
return HEX_SUCCESS;
}
|