diff options
Diffstat (limited to 'inline.h')
| -rw-r--r-- | inline.h | 45 |
1 files changed, 45 insertions, 0 deletions
@@ -486,6 +486,51 @@ C<L</is_utf8_fixed_width_buf_loclen_flags>>, #define is_utf8_string(s, len) is_utf8_string_loclen(s, len, NULL, NULL) +#if defined(PERL_CORE) || defined (PERL_EXT) + +/* +=for apidoc is_utf8_non_invariant_string + +Returns TRUE if L<perlapi/is_utf8_invariant_string> returns FALSE for the first +C<len> bytes of the string C<s>, but they are, nonetheless, legal Perl-extended +UTF-8; otherwise returns FALSE. + +A TRUE return means that at least one code point represented by the sequence +either is a wide character not representable as a single byte, or the +representation differs depending on whether the sequence is encoded in UTF-8 or +not. + +See also +C<L<perlapi/is_utf8_invariant_string>>, +C<L<perlapi/is_utf8_string>> + +=cut + +This is commonly used to determine if a SV's UTF-8 flag should be turned on. +It needn't be if its string is entirely UTF-8 invariant, and it shouldn't be if +it otherwise contains invalid UTF-8. + +It is an internal function because khw thinks that XS code shouldn't be working +at this low a level. A valid use case could change that. + +*/ + +PERL_STATIC_INLINE bool +S_is_utf8_non_invariant_string(const U8* const s, STRLEN len) +{ + const U8 * first_variant; + + PERL_ARGS_ASSERT_IS_UTF8_NON_INVARIANT_STRING; + + if (is_utf8_invariant_string_loc(s, len, &first_variant)) { + return FALSE; + } + + return is_utf8_string(first_variant, len - (first_variant - s)); +} + +#endif + /* =for apidoc is_strict_utf8_string |