diff options
Diffstat (limited to 'utf8.c')
| -rw-r--r-- | utf8.c | 86 |
1 files changed, 25 insertions, 61 deletions
@@ -800,13 +800,23 @@ S_isFF_overlong(const U8 * const s, const STRLEN len) return -1; } -#if defined(UV_IS_QUAD) /* These assume IV_MAX is 2**63-1 */ -# ifdef EBCDIC /* Actually is I8 */ -# define HIGHEST_REPRESENTABLE_UTF8 \ - "\xFF\xA7\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF" +/* At some point we may want to allow core to use up to UV_MAX */ + +#ifdef EBCDIC /* Actually is I8 */ +# if defined(UV_IS_QUAD) /* These assume IV_MAX is 2**63-1, UV_MAX 2**64-1 */ +# define HIGHEST_REPRESENTABLE_UTF8 "\xFF\xA7" + /* UV_MAX "\xFF\xAF" */ +# else /* These assume IV_MAX is 2**31-1, UV_MAX 2**32-1 */ +# define HIGHEST_REPRESENTABLE_UTF8 "\xFF\xA0\xA0\xA0\xA0\xA0\xA0\xA1" + /* UV_MAX "\xFF\xA0\xA0\xA0\xA0\xA0\xA0\xA3" */ +# endif +#else +# if defined(UV_IS_QUAD) +# define HIGHEST_REPRESENTABLE_UTF8 "\xFF\x80\x87" + /* UV_MAX "\xFF\x80" */ # else -# define HIGHEST_REPRESENTABLE_UTF8 \ - "\xFF\x80\x87\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF" +# define HIGHEST_REPRESENTABLE_UTF8 "\xFD" + /* UV_MAX "\xFE\x83" */ # endif #endif @@ -854,6 +864,15 @@ S_does_utf8_overflow(const U8 * const s, for (x = s; x < e; x++, y++) { + /* 'y' is set up to not include the trailing bytes that are all the + * maximum possible continuation byte. So when we reach the end of + * 'y' (known to be NUL terminated), it is impossible for 'x' to + * contain bytes larger than those omitted bytes, and therefore 'x' + * can't overflow */ + if (*y == '\0') { + return 0; + } + if (UNLIKELY(NATIVE_UTF8_TO_I8(*x) == *y)) { continue; } @@ -879,61 +898,6 @@ S_does_utf8_overflow(const U8 * const s, } -#if 0 - -/* This is the portions of the above function that deal with UV_MAX instead of - * IV_MAX. They are left here in case we want to combine them so that internal - * uses can have larger code points. The only logic difference is that the - * 32-bit EBCDIC platform is treate like the 64-bit, and the 32-bit ASCII has - * different logic. - */ - -/* Anything larger than this will overflow the word if it were converted into a UV */ -#if defined(UV_IS_QUAD) -# ifdef EBCDIC /* Actually is I8 */ -# define HIGHEST_REPRESENTABLE_UTF8 \ - "\xFF\xAF\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF" -# else -# define HIGHEST_REPRESENTABLE_UTF8 \ - "\xFF\x80\x8F\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF" -# endif -#else /* 32-bit */ -# ifdef EBCDIC -# define HIGHEST_REPRESENTABLE_UTF8 \ - "\xFF\xA0\xA0\xA0\xA0\xA0\xA0\xA3\xBF\xBF\xBF\xBF\xBF\xBF" -# else -# define HIGHEST_REPRESENTABLE_UTF8 "\xFE\x83\xBF\xBF\xBF\xBF\xBF" -# endif -#endif - -#ifndef HAS_EXTRA_LONG_UTF8 - - /* On 32 bit ASCII machines, many overlongs that start with FF don't - * overflow */ - if (consider_overlongs && isFF_OVERLONG(s, len) > 0) { - - /* To be such an overlong, the first bytes of 's' must match - * FF_OVERLONG_PREFIX, which is "\xff\x80\x80\x80\x80\x80\x80". If we - * don't have any additional bytes available, the sequence, when - * completed might or might not fit in 32 bits. But if we have that - * next byte, we can tell for sure. If it is <= 0x83, then it does - * fit. */ - if (len <= STRLENs(FF_OVERLONG_PREFIX)) { - return -1; - } - - return s[STRLENs(FF_OVERLONG_PREFIX)] > 0x83; - } - -/* Starting with the #else, the rest of the function is identical except - * 1. we need to move the 'len' declaration to be global to the function - * 2. the endif move to just after the UNUSED_ARG. - * An empty endif is given just below to satisfy the preprocessor - */ -#endif - -#endif - #undef FF_OVERLONG_PREFIX STRLEN |