neovim/src/tree_sitter/utf16.c

34 lines
653 B
C

#include "./utf16.h"
utf8proc_ssize_t utf16_iterate(
const utf8proc_uint8_t *string,
utf8proc_ssize_t length,
utf8proc_int32_t *code_point
) {
if (length < 2) {
*code_point = -1;
return 0;
}
uint16_t *units = (uint16_t *)string;
uint16_t unit = units[0];
if (unit < 0xd800 || unit >= 0xe000) {
*code_point = unit;
return 2;
}
if (unit < 0xdc00) {
if (length >= 4) {
uint16_t next_unit = units[1];
if (next_unit >= 0xdc00 && next_unit < 0xe000) {
*code_point = 0x10000 + ((unit - 0xd800) << 10) + (next_unit - 0xdc00);
return 4;
}
}
}
*code_point = -1;
return 2;
}