hb_codepoint_t *unicode,
hb_codepoint_t replacement)
{
- const uint16_t *end = text--;
- hb_codepoint_t c = *text;
+ hb_codepoint_t c = *--text;
if (likely (!hb_in_range (c, 0xD800u, 0xDFFFu)))
{
return text;
}
- if (likely (start < text && hb_in_range (c, 0xDC00u, 0xDFFFu)))
- text--;
-
- if (likely (next (text, end, unicode, replacement) == end))
- return text;
+ if (likely (c >= 0xDC00u && start < text))
+ {
+ /* Low-surrogate in c */
+ hb_codepoint_t h = text[-1];
+ if (likely (hb_in_range (h, 0xD800u, 0xDBFFu)))
+ {
+ /* High-surrogate in h */
+ *unicode = (h << 10) + c - ((0xD800u << 10) - 0x10000u + 0xDC00u);
+ text--;
+ return text;
+ }
+ }
+ /* Lonely / out-of-order surrogate. */
*unicode = replacement;
- return end - 1;
+ return text;
}
hb_codepoint_t *unicode,
hb_codepoint_t replacement)
{
- next (text - 1, text, unicode, replacement);
- return text - 1;
+ hb_codepoint_t c = *unicode = *--text;
+ if (validate && unlikely (c >= 0xD800u && (c <= 0xDFFFu || c > 0x10FFFFu)))
+ *unicode = replacement;
+ return text;
}
static inline unsigned int