+ if (iter->next_done)
+ return;
+ if (iter->in_shift)
+ goto with_shift;
+ /* Handle most ASCII characters quickly, without calling mbrtowc(). */
+ if (is_basic (*iter->cur.ptr))
+ {
+ /* These characters are part of the basic character set. ISO C 99
+ guarantees that their wide character code is identical to their
+ char code. */
+ iter->cur.bytes = 1;
+ iter->cur.wc = *iter->cur.ptr;
+ iter->cur.wc_valid = true;
+ }
+ else
+ {
+ assert (mbsinit (&iter->state));
+ iter->in_shift = true;
+ with_shift:
+ iter->cur.bytes = mbrtowc (&iter->cur.wc, iter->cur.ptr,
+ strnlen1 (iter->cur.ptr, MB_CUR_MAX),
+ &iter->state);
+ if (iter->cur.bytes == (size_t) -1)
+ {
+ /* An invalid multibyte sequence was encountered. */
+ iter->cur.bytes = 1;
+ iter->cur.wc_valid = false;
+ /* Whether to set iter->in_shift = false and reset iter->state
+ or not is not very important; the string is bogus anyway. */
+ }
+ else if (iter->cur.bytes == (size_t) -2)
+ {
+ /* An incomplete multibyte character at the end. */
+ iter->cur.bytes = strlen (iter->cur.ptr) + 1;
+ iter->cur.wc_valid = false;
+ /* Whether to set iter->in_shift = false and reset iter->state
+ or not is not important; the string end is reached anyway. */
+ }
+ else
+ {
+ if (iter->cur.bytes == 0)
+ {
+ /* A null wide character was encountered. */
+ iter->cur.bytes = 1;
+ assert (*iter->cur.ptr == '\0');
+ assert (iter->cur.wc == 0);
+ }
+ iter->cur.wc_valid = true;
+
+ /* When in the initial state, we can go back treating ASCII
+ characters more quickly. */
+ if (mbsinit (&iter->state))
+ iter->in_shift = false;
+ }
+ }
+ iter->next_done = true;
+}
+
+static inline void
+mbiter_multi_reloc (struct mbiter_multi *iter, ptrdiff_t ptrdiff)
+{
+ iter->cur.ptr += ptrdiff;
+}