blob: c7e740d582f4e94e5b8893b284790ddcd998306d (
plain)
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
|
//
// GTMNSData+Hex.m
//
// Copyright 2009 Google Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License"); you may not
// use this file except in compliance with the License. You may obtain a copy
// of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
// License for the specific language governing permissions and limitations under
// the License.
//
#import "GTMNSData+Hex.h"
#import "GTMDefines.h"
@implementation NSData (GTMHexAdditions)
+ (NSData *)gtm_dataWithHexString:(NSString *)hexString {
NSData *hexData = [hexString dataUsingEncoding:NSASCIIStringEncoding];
const char *hexBuf = [hexData bytes];
NSUInteger hexLen = [hexData length];
// This indicates an error converting to ASCII.
if (hexString && !hexData) {
return nil;
}
if ((hexLen % 2) != 0) {
return nil;
}
NSMutableData *binaryData = [NSMutableData dataWithLength:(hexLen / 2)];
unsigned char *binaryPtr = [binaryData mutableBytes];
unsigned char value = 0;
for (NSUInteger i = 0; i < hexLen; i++) {
char c = hexBuf[i];
if (!isxdigit(c)) {
return nil;
}
if (isdigit(c)) {
value += c - '0';
} else if (islower(c)) {
value += 10 + c - 'a';
} else {
value += 10 + c - 'A';
}
if (i & 1) {
*binaryPtr++ = value;
value = 0;
} else {
value <<= 4;
}
}
return [NSData dataWithData:binaryData];
}
- (NSString *)gtm_hexString {
static const char kHexTable[] =
"000102030405060708090a0b0c0d0e0f"
"101112131415161718191a1b1c1d1e1f"
"202122232425262728292a2b2c2d2e2f"
"303132333435363738393a3b3c3d3e3f"
"404142434445464748494a4b4c4d4e4f"
"505152535455565758595a5b5c5d5e5f"
"606162636465666768696a6b6c6d6e6f"
"707172737475767778797a7b7c7d7e7f"
"808182838485868788898a8b8c8d8e8f"
"909192939495969798999a9b9c9d9e9f"
"a0a1a2a3a4a5a6a7a8a9aaabacadaeaf"
"b0b1b2b3b4b5b6b7b8b9babbbcbdbebf"
"c0c1c2c3c4c5c6c7c8c9cacbcccdcecf"
"d0d1d2d3d4d5d6d7d8d9dadbdcdddedf"
"e0e1e2e3e4e5e6e7e8e9eaebecedeeef"
"f0f1f2f3f4f5f6f7f8f9fafbfcfdfeff";
const unsigned char *binaryPtr = [self bytes];
NSUInteger binaryLen = [self length];
NSMutableData *hexData = [NSMutableData dataWithLength:(2 * binaryLen)];
char *hexPtr = [hexData mutableBytes];
for (NSUInteger i = 0; i < binaryLen; i++) {
*hexPtr++ = kHexTable[(*binaryPtr)*2];
*hexPtr++ = kHexTable[(*binaryPtr)*2 + 1];
++binaryPtr;
}
return [[[NSString alloc] initWithData:hexData
encoding:NSASCIIStringEncoding] autorelease];
}
@end
|