toaruos/base/usr/include/toaru/decodeutf8.h

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2018-08-19 15:03:06 +03:00
/*
* Stateful UTF-8 decoder
*/
#include <stdint.h>
#define UTF8_ACCEPT 0
#define UTF8_REJECT 1
static inline uint32_t decode(uint32_t* state, uint32_t* codep, uint32_t byte) {
static int state_table[32] = {
0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 0xxxxxxx */
1,1,1,1,1,1,1,1, /* 10xxxxxx */
2,2,2,2, /* 110xxxxx */
3,3, /* 1110xxxx */
4, /* 11110xxx */
1 /* 11111xxx */
};
static int mask_bytes[32] = {
0x7F,0x7F,0x7F,0x7F,0x7F,0x7F,0x7F,0x7F,
0x7F,0x7F,0x7F,0x7F,0x7F,0x7F,0x7F,0x7F,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x1F,0x1F,0x1F,0x1F,
0x0F,0x0F,
0x07,
0x00
};
static int next[5] = {
0,
1,
0,
2,
3
};
if (*state == UTF8_ACCEPT) {
*codep = byte & mask_bytes[byte >> 3];
*state = state_table[byte >> 3];
} else if (*state > 0) {
*codep = (byte & 0x3F) | (*codep << 6);
*state = next[*state];
}
return *state;
}