blob: f1ab6d7a457a2d3f1147de7b9c5eb2000bb9447e (
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
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
|
/*
* This file is part of LibCSS.
* Licensed under the MIT License,
* http://www.opensource.org/licenses/mit-license.php
* Copyright 2007-8 John-Mark Bell <jmb@netsurf-browser.org>
*/
#ifndef css_utils_h_
#define css_utils_h_
#include <libcss/types.h>
#include "utils/fpmath.h"
#ifndef max
#define max(a,b) ((a)>(b)?(a):(b))
#endif
#ifndef min
#define min(a,b) ((a)<(b)?(a):(b))
#endif
#ifndef SLEN
/* Calculate length of a string constant */
#define SLEN(s) (sizeof((s)) - 1) /* -1 for '\0' */
#endif
#ifndef UNUSED
#define UNUSED(x) ((x)=(x))
#endif
static inline fixed number_from_css_string(const css_string *string,
size_t *consumed)
{
size_t len;
const uint8_t *ptr;
int sign = 1;
int32_t intpart = 0;
int32_t fracpart = 0;
int32_t pwr = 1;
if (string == NULL || string->len == 0 || consumed == NULL)
return 0;
len = string->len;
ptr = string->ptr;
/* number = [+-]? ([0-9]+ | [0-9]* '.' [0-9]+) */
/* Extract sign, if any */
if (ptr[0] == '-') {
sign = -1;
len--;
ptr++;
} else if (ptr[0] == '+') {
len--;
ptr++;
}
/* Ensure we have either a digit or a '.' followed by a digit */
if (len == 0) {
*consumed = 0;
return 0;
} else {
if (ptr[0] == '.') {
if (len == 1 || ptr[1] < '0' || '9' < ptr[1]) {
*consumed = 0;
return 0;
}
} else if (ptr[0] < '0' || '9' < ptr[0]) {
*consumed = 0;
return 0;
}
}
/* Now extract intpart, assuming base 10 */
while (len > 0) {
/* Stop on first non-digit */
if (ptr[0] < '0' || '9' < ptr[0])
break;
/* Clamp to a max of 2^22 - 1 */
if (intpart < (1 << 22)) {
intpart *= 10;
intpart += ptr[0] - '0';
}
ptr++;
len--;
}
/* And fracpart, again, assuming base 10 */
if (len > 1 && ptr[0] == '.' && ('0' <= ptr[1] && ptr[1] <= '9')) {
ptr++;
len--;
while (len > 0) {
if (ptr[0] < '0' || '9' < ptr[0])
break;
if (pwr < 1000000) {
pwr *= 10;
fracpart *= 10;
fracpart += ptr[0] - '0';
}
ptr++;
len--;
}
fracpart = ((1 << 10) * fracpart + pwr/2) / pwr;
/* Extra paranoid clamp to maximum fractional part */
if (fracpart >= (1 << 10))
fracpart = (1 << 10) - 1;
}
/* If the intpart is larger than we can represent,
* then clamp to the maximum value we can store. */
if (intpart >= (1 << 21)) {
fracpart = (1 << 10) - 1;
intpart = (1 << 21) - 1;
}
*consumed = ptr - string->ptr;
return FMULI(((intpart << 10) | fracpart), sign);
}
#endif
|