uCBQN/src/utf.c

56 lines
1.9 KiB
C

i8 utf8_len(u8 ch) {
if (ch<128) return 1;
if ((ch>>5)== 0b110) return 2;
if ((ch>>4)== 0b1110) return 3;
if ((ch>>3)==0b11110) return 4;
return -1;
}
u32 utf8_p(u8* p) {
i32 len = utf8_len(*p);
switch (len) { default: UD;
case -1: return (u32)-1;
case 1: return *p;
case 2: return (0b11111u&*p)<< 6 | (0b111111u&p[1]);
case 3: return (0b1111u &*p)<<12 | (0b111111u&p[2]) | (0b111111u&p[1])<<6;
case 4: return (0b111u &*p)<<18 | (0b111111u&p[3]) | (0b111111u&p[2])<<6 | (0b111111u&p[1])<<12;
}
}
B fromUTF8(char* s, i64 len) {
u64 sz = 0;
i64 j = 0;
while (true) {
i8 l = utf8_len((u8)s[j]);
if (l==-1) thrM("Invalid UTF-8");
if (j>=len) {
if (j!=len) thrM("Invalid UTF-8");
break;
}
sz++;
j+= l;
}
B r = m_c32arrv(sz);
u32* rp = c32arr_ptr(r);
u64 p = 0;
// TODO verify
for (i64 i = 0; i < len; i+= utf8_len((u8)s[i])) rp[p++] = utf8_p((u8*)s+i); // may read after end, eh
return r;
}
B fromUTF8l(char* s) {
return fromUTF8(s, strlen(s));
}
void printUTF8(u32 c) {
if (c<128) printf("%c", c);
else if (c<=0x07FF) printf("%c%c" , 0xC0| c>>6 , 0x80| (c &0x3F) );
else if (c<=0xFFFF) printf("%c%c%c" , 0xE0| c>>12, 0x80| (c>>6 &0x3F), 0x80| (c &0x3F) );
else printf("%c%c%c%c", 0xF0| c>>18, 0x80| (c>>12 &0x3F), 0x80| (c>>6 &0x3F), 0x80| (c&0x3F));
}
u64 snprintUTF8(char* p, u64 l, u32 c) {
if (c<128) return snprintf(p, l, "%c", c);
else if (c<=0x07FF) return snprintf(p, l, "%c%c" , 0xC0| c>>6 , 0x80| (c &0x3F) );
else if (c<=0xFFFF) return snprintf(p, l, "%c%c%c" , 0xE0| c>>12, 0x80| (c>>6 &0x3F), 0x80| (c &0x3F) );
else return snprintf(p, l, "%c%c%c%c", 0xF0| c>>18, 0x80| (c>>12 &0x3F), 0x80| (c>>6 &0x3F), 0x80| (c&0x3F));
}