mirror of
https://github.com/swaywm/sway.git
synced 2024-08-31 08:07:01 +00:00
102 lines
1.5 KiB
C
102 lines
1.5 KiB
C
|
#include <stdint.h>
|
||
|
#include <stddef.h>
|
||
|
#include "unicode.h"
|
||
|
|
||
|
size_t utf8_chsize(uint32_t ch) {
|
||
|
if (ch < 0x80) {
|
||
|
return 1;
|
||
|
} else if (ch < 0x800) {
|
||
|
return 2;
|
||
|
} else if (ch < 0x10000) {
|
||
|
return 3;
|
||
|
}
|
||
|
return 4;
|
||
|
}
|
||
|
|
||
|
static const uint8_t masks[] = {
|
||
|
0x7F,
|
||
|
0x1F,
|
||
|
0x0F,
|
||
|
0x07,
|
||
|
0x03,
|
||
|
0x01
|
||
|
};
|
||
|
|
||
|
uint32_t utf8_decode(const char **char_str) {
|
||
|
uint8_t **s = (uint8_t **)char_str;
|
||
|
|
||
|
uint32_t cp = 0;
|
||
|
if (**s < 128) {
|
||
|
// shortcut
|
||
|
cp = **s;
|
||
|
++*s;
|
||
|
return cp;
|
||
|
}
|
||
|
int size = utf8_size((char *)*s);
|
||
|
if (size == -1) {
|
||
|
++*s;
|
||
|
return UTF8_INVALID;
|
||
|
}
|
||
|
uint8_t mask = masks[size - 1];
|
||
|
cp = **s & mask;
|
||
|
++*s;
|
||
|
while (--size) {
|
||
|
cp <<= 6;
|
||
|
cp |= **s & 0x3f;
|
||
|
++*s;
|
||
|
}
|
||
|
return cp;
|
||
|
}
|
||
|
|
||
|
size_t utf8_encode(char *str, uint32_t ch) {
|
||
|
size_t len = 0;
|
||
|
uint8_t first;
|
||
|
|
||
|
if (ch < 0x80) {
|
||
|
first = 0;
|
||
|
len = 1;
|
||
|
} else if (ch < 0x800) {
|
||
|
first = 0xc0;
|
||
|
len = 2;
|
||
|
} else if (ch < 0x10000) {
|
||
|
first = 0xe0;
|
||
|
len = 3;
|
||
|
} else {
|
||
|
first = 0xf0;
|
||
|
len = 4;
|
||
|
}
|
||
|
|
||
|
for (size_t i = len - 1; i > 0; --i) {
|
||
|
str[i] = (ch & 0x3f) | 0x80;
|
||
|
ch >>= 6;
|
||
|
}
|
||
|
|
||
|
str[0] = ch | first;
|
||
|
return len;
|
||
|
}
|
||
|
|
||
|
|
||
|
static const struct {
|
||
|
uint8_t mask;
|
||
|
uint8_t result;
|
||
|
int octets;
|
||
|
} sizes[] = {
|
||
|
{ 0x80, 0x00, 1 },
|
||
|
{ 0xE0, 0xC0, 2 },
|
||
|
{ 0xF0, 0xE0, 3 },
|
||
|
{ 0xF8, 0xF0, 4 },
|
||
|
{ 0xFC, 0xF8, 5 },
|
||
|
{ 0xFE, 0xF8, 6 },
|
||
|
{ 0x80, 0x80, -1 },
|
||
|
};
|
||
|
|
||
|
int utf8_size(const char *s) {
|
||
|
uint8_t c = (uint8_t)*s;
|
||
|
for (size_t i = 0; i < sizeof(sizes) / 2; ++i) {
|
||
|
if ((c & sizes[i].mask) == sizes[i].result) {
|
||
|
return sizes[i].octets;
|
||
|
}
|
||
|
}
|
||
|
return -1;
|
||
|
}
|