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
|
#ifndef UTF8_H_INCLUDED
#define UTF8_H_INCLUDED
/*
// Example:
#include <stc/cstr.h>
#include <stc/csview.h>
int main()
{
c_auto (cstr, s1) {
s1 = cstr_new("hell😀 w😀rld");
cstr_replace_sv(&s1, utf8_substr(s1.str, 7, 1), c_sv("x"));
printf("%s\n", s1.str);
csview sv = csview_from_s(s1);
c_foreach (i, csview, sv)
printf(c_PRIsv ",", c_ARGsv(i.cp));
}
}
// Output:
// hell😀 wxrld
// h,e,l,l,😀, ,w,x,r,l,d,
*/
#include "ccommon.h"
#include <ctype.h>
/* number of codepoints in the utf8 string s, or SIZE_MAX if invalid utf8: */
enum { UTF8_OK = 0, UTF8_ERROR = 4 };
typedef struct { uint32_t state, codep, len; } utf8_decode_t;
/* decode next utf8 codepoint. */
STC_API uint32_t utf8_decode(utf8_decode_t *c, const uint8_t b);
STC_API const uint8_t* utf8_nextc(utf8_decode_t *c, const uint8_t* s);
STC_API size_t utf8_size(const char *s);
STC_API size_t utf8_size_n(const char *s, size_t n);
STC_API const char* utf8_at(const char *s, size_t index);
STC_INLINE size_t utf8_pos(const char* s, size_t index)
{ return utf8_at(s, index) - s; }
STC_INLINE bool utf8_valid(const char* s)
{ return utf8_size(s) != SIZE_MAX; }
STC_INLINE uint32_t utf8_peek(const char *s) {
utf8_decode_t ctx = {UTF8_OK, 0};
utf8_nextc(&ctx, (const uint8_t*)s);
return ctx.codep;
}
STC_INLINE size_t utf8_codep_size(const char *s) {
utf8_decode_t ctx = {UTF8_OK, 0};
utf8_nextc(&ctx, (const uint8_t*)s);
return ctx.len;
}
STC_INLINE const char* utf8_next(const char *s) {
if (!*s) return NULL;
utf8_decode_t ctx = {UTF8_OK, 0};
return (const char*) utf8_nextc(&ctx, (const uint8_t*)s);
}
// --------------------------- IMPLEMENTATION ---------------------------------
#ifdef _i_implement
// https://news.ycombinator.com/item?id=15423674
// https://gist.github.com/s4y/344a355f8c1f99c6a4cb2347ec4323cc
STC_DEF uint32_t utf8_decode(utf8_decode_t *c, const uint8_t b)
{
switch (c->state) {
case UTF8_OK:
if (b < 0x80) c->codep = b, c->len = 1;
else if (b < 0xc2) c->state = UTF8_ERROR;
else if (b < 0xe0) c->state = 1, c->codep = b & 0x1f, c->len = 2;
else if (b < 0xf0) c->state = 2, c->codep = b & 0xf, c->len = 3;
else if (b < 0xf5) c->state = 3, c->codep = b & 0x7, c->len = 4;
else c->state = UTF8_ERROR;
break;
case 1: case 2: case 3:
if ((b & 0xc0) == 0x80) {
c->state -= 1;
c->codep = (c->codep << 6) | (b & 0x3f);
} else
c->state = UTF8_ERROR;
}
return c->state;
}
STC_DEF const uint8_t* utf8_nextc(utf8_decode_t *c, const uint8_t* s) {
utf8_decode(c, *s++);
switch (c->len) {
case 4: utf8_decode(c, *s++);
case 3: utf8_decode(c, *s++);
case 2: utf8_decode(c, *s++);
}
return s;
}
STC_DEF size_t utf8_size(const char *s)
{
utf8_decode_t ctx = {UTF8_OK, 0};
size_t size = 0;
while (*s)
size += !utf8_decode(&ctx, (uint8_t)*s++);
return !ctx.state ? size : SIZE_MAX;
}
STC_DEF size_t utf8_size_n(const char *s, size_t n)
{
utf8_decode_t ctx = {UTF8_OK, 0};
size_t size = 0;
while ((n-- != 0) & (*s != 0))
size += !utf8_decode(&ctx, (uint8_t)*s++);
return !ctx.state ? size : SIZE_MAX;
}
STC_DEF const char* utf8_at(const char *s, size_t index)
{
utf8_decode_t ctx = {UTF8_OK, 0};
for (size_t i = 0; (i < index) & (*s != 0); ++s)
i += !utf8_decode(&ctx, (uint8_t)*s);
return s;
}
#endif
#endif
#undef i_opt
|
