/* utf8.h
*
- * Copyright (c) 1998-2002, Larry Wall
+ * Copyright (C) 2000, 2001, 2002, by Larry Wall and others
*
* You may distribute under the terms of either the GNU General Public
* License or the Artistic License, as specified in the README file.
*/
/* Use UTF-8 as the default script encoding?
- * Turning this on will break scripts having non-UTF8 binary
+ * Turning this on will break scripts having non-UTF-8 binary
* data (such as Latin-1) in string literals. */
#ifdef USE_UTF8_SCRIPTS
# define USE_UTF8_IN_NAMES (!IN_BYTES)
#endif
END_EXTERN_C
-#define UTF8SKIP(s) PL_utf8skip[*(U8*)s]
+#define UTF8SKIP(s) PL_utf8skip[*(const U8*)(s)]
/* Native character to iso-8859-1 */
#define NATIVE_TO_ASCII(ch) (ch)
Note the A0..BF in U+0800..U+0FFF, the 80..9F in U+D000...U+D7FF,
the 90..BF in U+10000..U+3FFFF, and the 80...8F in U+100000..U+10FFFF.
+The "gaps" are caused by legal UTF-8 avoiding non-shortest encodings:
+it is technically possible to UTF-8-encode a single code point in different
+ways, but that is explicitly forbidden, and the shortest possible encoding
+should always be used (and that is what Perl does).
*/
* (that is, the two high bits are set). Otherwise we risk loading in the
* heavy-duty SWASHINIT and SWASHGET routines unnecessarily.
*/
-#define isIDFIRST_lazy_if(p,c) ((IN_BYTES || (!c || (*((U8*)p) < 0xc0))) \
+#define isIDFIRST_lazy_if(p,c) ((IN_BYTES || (!c || (*((const U8*)p) < 0xc0))) \
? isIDFIRST(*(p)) \
- : isIDFIRST_utf8((U8*)p))
-#define isALNUM_lazy_if(p,c) ((IN_BYTES || (!c || (*((U8*)p) < 0xc0))) \
+ : isIDFIRST_utf8((const U8*)p))
+#define isALNUM_lazy_if(p,c) ((IN_BYTES || (!c || (*((const U8*)p) < 0xc0))) \
? isALNUM(*(p)) \
- : isALNUM_utf8((U8*)p))
+ : isALNUM_utf8((const U8*)p))
#endif /* EBCDIC vs ASCII */
#define isIDFIRST_lazy(p) isIDFIRST_lazy_if(p,1)
#define isALNUM_lazy(p) isALNUM_lazy_if(p,1)
-/* how wide can a single UTF8 encoded character become */
-#define UTF8_MAXLEN 13
-/* how wide a character can become when upper/lowercased */
-#define UTF8_MAXLEN_UCLC_MULT 3
-#define UTF8_MAXLEN_UCLC (UTF8_MAXLEN*UTF8_MAXLEN_UCLC_MULT)
-/* how wide a character can become when casefolded */
-#define UTF8_MAXLEN_FOLD_MULT 3
-#define UTF8_MAXLEN_FOLD (UTF8_MAXLEN*UTF8_MAXLEN_FOLD_MULT)
+#define UTF8_MAXBYTES 13
+/* How wide can a single UTF-8 encoded character become in bytes.
+ * NOTE: Strictly speaking Perl's UTF-8 should not be called UTF-8
+ * since UTF-8 is an encoding of Unicode and given Unicode's current
+ * upper limit only four bytes is possible. Perl thinks of UTF-8
+ * as a way to encode non-negative integers in a binary format. */
+#define UTF8_MAXLEN UTF8_MAXBYTES
+
+#define UTF8_MAXLEN_UCLC 3 /* Obsolete, do not use. */
+#define UTF8_MAXLEN_UCLC_MULT 39 /* Obsolete, do not use. */
+#define UTF8_MAXLEN_FOLD 3 /* Obsolete, do not use. */
+#define UTF8_MAXLEN_FOLD_MULT 39 /* Obsolete, do not use. */
+
+/* The maximum number of UTF-8 bytes a single Unicode character can
+ * uppercase/lowercase/fold into; this number depends on the Unicode
+ * version. An example of maximal expansion is the U+03B0 which
+ * uppercases to U+03C5 U+0308 U+0301. The Unicode databases that
+ * tell these things are UnicodeDatabase.txt, CaseFolding.txt, and
+ * SpecialCasing.txt. */
+#define UTF8_MAXBYTES_CASE 6
#define IN_BYTES (PL_curcop->op_private & HINT_BYTES)
#define DO_UTF8(sv) (SvUTF8(sv) && !IN_BYTES)
#define UTF8_ALLOW_FE_FF 0x0008
#define UTF8_ALLOW_SHORT 0x0010
#define UTF8_ALLOW_SURROGATE 0x0020
-#define UTF8_ALLOW_BOM 0x0040
-#define UTF8_ALLOW_FFFF 0x0080
-#define UTF8_ALLOW_LONG 0x0100
+#define UTF8_ALLOW_FFFF 0x0040 /* Allows also FFFE. */
+#define UTF8_ALLOW_LONG 0x0080
#define UTF8_ALLOW_ANYUV (UTF8_ALLOW_EMPTY|UTF8_ALLOW_FE_FF|\
- UTF8_ALLOW_SURROGATE|UTF8_ALLOW_BOM|\
- UTF8_ALLOW_FFFF|UTF8_ALLOW_LONG)
-#define UTF8_ALLOW_ANY 0x00ff
+ UTF8_ALLOW_SURROGATE|UTF8_ALLOW_FFFF)
+#define UTF8_ALLOW_ANY 0x00FF
#define UTF8_CHECK_ONLY 0x0200
-#define UNICODE_SURROGATE_FIRST 0xd800
-#define UNICODE_SURROGATE_LAST 0xdfff
-#define UNICODE_REPLACEMENT 0xfffd
-#define UNICODE_BYTE_ORDER_MARK 0xfeff
-#define UNICODE_ILLEGAL 0xffff
+#define UNICODE_SURROGATE_FIRST 0xD800
+#define UNICODE_SURROGATE_LAST 0xDFFF
+#define UNICODE_REPLACEMENT 0xFFFD
+#define UNICODE_BYTE_ORDER_MARK 0xFEFF
+#define UNICODE_ILLEGAL 0xFFFF
/* Though our UTF-8 encoding can go beyond this,
* let's be conservative and do as Unicode 3.2 says. */
#define UNICODE_ALLOW_SURROGATE 0x0001 /* Allow UTF-16 surrogates (EVIL) */
#define UNICODE_ALLOW_FDD0 0x0002 /* Allow the U+FDD0...U+FDEF */
-#define UNICODE_ALLOW_BOM 0x0004 /* Allow 0xFEFF */
-#define UNICODE_ALLOW_FFFF 0x0008 /* Allow 0xFFFF, 0x1FFFF, ... */
-#define UNICODE_ALLOW_SUPER 0x0010 /* Allow past 10xFFFF */
-#define UNICODE_ALLOW_ANY 0xFFFF
+#define UNICODE_ALLOW_FFFF 0x0004 /* Allow 0xFFF[EF], 0x1FFF[EF], ... */
+#define UNICODE_ALLOW_SUPER 0x0008 /* Allow past 10xFFFF */
+#define UNICODE_ALLOW_ANY 0x000F
#define UNICODE_IS_SURROGATE(c) ((c) >= UNICODE_SURROGATE_FIRST && \
(c) <= UNICODE_SURROGATE_LAST)