xref: /openbsd-src/gnu/usr.bin/perl/utf8.h (revision f1dd7b858388b4a23f4f67a4957ec5ff656ebbe8)
1 /*    utf8.h
2  *
3  * This file contains definitions for use with the UTF-8 encoding.  It
4  * actually also works with the variant UTF-8 encoding called UTF-EBCDIC, and
5  * hides almost all of the differences between these from the caller.  In other
6  * words, someone should #include this file, and if the code is being compiled
7  * on an EBCDIC platform, things should mostly just work.
8  *
9  *    Copyright (C) 2000, 2001, 2002, 2005, 2006, 2007, 2009,
10  *    2010, 2011 by Larry Wall and others
11  *
12  *    You may distribute under the terms of either the GNU General Public
13  *    License or the Artistic License, as specified in the README file.
14  *
15  */
16 
17 #ifndef PERL_UTF8_H_      /* Guard against recursive inclusion */
18 #define PERL_UTF8_H_ 1
19 
20 /* Use UTF-8 as the default script encoding?
21  * Turning this on will break scripts having non-UTF-8 binary
22  * data (such as Latin-1) in string literals. */
23 #ifdef USE_UTF8_SCRIPTS
24 #    define USE_UTF8_IN_NAMES (!IN_BYTES)
25 #else
26 #    define USE_UTF8_IN_NAMES (PL_hints & HINT_UTF8)
27 #endif
28 
29 #include "regcharclass.h"
30 #include "unicode_constants.h"
31 
32 /* For to_utf8_fold_flags, q.v. */
33 #define FOLD_FLAGS_LOCALE       0x1
34 #define FOLD_FLAGS_FULL         0x2
35 #define FOLD_FLAGS_NOMIX_ASCII  0x4
36 
37 /*
38 =head1 Unicode Support
39 L<perlguts/Unicode Support> has an introduction to this API.
40 
41 See also L</Character classification>,
42 and L</Character case changing>.
43 Various functions outside this section also work specially with Unicode.
44 Search for the string "utf8" in this document.
45 
46 =for apidoc is_ascii_string
47 
48 This is a misleadingly-named synonym for L</is_utf8_invariant_string>.
49 On ASCII-ish platforms, the name isn't misleading: the ASCII-range characters
50 are exactly the UTF-8 invariants.  But EBCDIC machines have more invariants
51 than just the ASCII characters, so C<is_utf8_invariant_string> is preferred.
52 
53 =for apidoc is_invariant_string
54 
55 This is a somewhat misleadingly-named synonym for L</is_utf8_invariant_string>.
56 C<is_utf8_invariant_string> is preferred, as it indicates under what conditions
57 the string is invariant.
58 
59 =cut
60 */
61 #define is_ascii_string(s, len)     is_utf8_invariant_string(s, len)
62 #define is_invariant_string(s, len) is_utf8_invariant_string(s, len)
63 
64 #define uvoffuni_to_utf8_flags(d,uv,flags)                                     \
65                                uvoffuni_to_utf8_flags_msgs(d, uv, flags, 0)
66 #define uvchr_to_utf8(a,b)          uvchr_to_utf8_flags(a,b,0)
67 #define uvchr_to_utf8_flags(d,uv,flags)                                        \
68                                     uvchr_to_utf8_flags_msgs(d,uv,flags, 0)
69 #define uvchr_to_utf8_flags_msgs(d,uv,flags,msgs)                              \
70                 uvoffuni_to_utf8_flags_msgs(d,NATIVE_TO_UNI(uv),flags, msgs)
71 #define utf8_to_uvchr_buf(s, e, lenp)                                          \
72             utf8_to_uvchr_buf_helper((const U8 *) (s), (const U8 *) e, lenp)
73 #define utf8n_to_uvchr(s, len, lenp, flags)                                    \
74                                 utf8n_to_uvchr_error(s, len, lenp, flags, 0)
75 #define utf8n_to_uvchr_error(s, len, lenp, flags, errors)                      \
76                         utf8n_to_uvchr_msgs(s, len, lenp, flags, errors, 0)
77 
78 #define to_uni_fold(c, p, lenp) _to_uni_fold_flags(c, p, lenp, FOLD_FLAGS_FULL)
79 
80 #define foldEQ_utf8(s1, pe1, l1, u1, s2, pe2, l2, u2) \
81 		    foldEQ_utf8_flags(s1, pe1, l1, u1, s2, pe2, l2, u2, 0)
82 #define FOLDEQ_UTF8_NOMIX_ASCII   (1 << 0)
83 #define FOLDEQ_LOCALE             (1 << 1)
84 #define FOLDEQ_S1_ALREADY_FOLDED  (1 << 2)
85 #define FOLDEQ_S2_ALREADY_FOLDED  (1 << 3)
86 #define FOLDEQ_S1_FOLDS_SANE      (1 << 4)
87 #define FOLDEQ_S2_FOLDS_SANE      (1 << 5)
88 
89 #define ibcmp_utf8(s1, pe1, l1, u1, s2, pe2, l2, u2) \
90 		    cBOOL(! foldEQ_utf8(s1, pe1, l1, u1, s2, pe2, l2, u2))
91 
92 #ifdef EBCDIC
93 /* The equivalent of these macros but implementing UTF-EBCDIC
94    are in the following header file:
95  */
96 
97 #include "utfebcdic.h"
98 
99 #else	/* ! EBCDIC */
100 START_EXTERN_C
101 
102 /*
103 
104 =for apidoc AmnU|STRLEN|UTF8_MAXBYTES
105 
106 The maximum width of a single UTF-8 encoded character, in bytes.
107 
108 NOTE: Strictly speaking Perl's UTF-8 should not be called UTF-8 since UTF-8
109 is an encoding of Unicode, and Unicode's upper limit, 0x10FFFF, can be
110 expressed with 4 bytes.  However, Perl thinks of UTF-8 as a way to encode
111 non-negative integers in a binary format, even those above Unicode.
112 
113 =cut
114  */
115 #define UTF8_MAXBYTES 13
116 
117 #ifdef DOINIT
118 EXTCONST unsigned char PL_utf8skip[] = {
119 /* 0x00 */ 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, /* ascii */
120 /* 0x10 */ 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, /* ascii */
121 /* 0x20 */ 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, /* ascii */
122 /* 0x30 */ 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, /* ascii */
123 /* 0x40 */ 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, /* ascii */
124 /* 0x50 */ 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, /* ascii */
125 /* 0x60 */ 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, /* ascii */
126 /* 0x70 */ 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, /* ascii */
127 /* 0x80 */ 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, /* bogus: continuation byte */
128 /* 0x90 */ 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, /* bogus: continuation byte */
129 /* 0xA0 */ 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, /* bogus: continuation byte */
130 /* 0xB0 */ 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, /* bogus: continuation byte */
131 /* 0xC0 */ 2,2,				    /* overlong */
132 /* 0xC2 */     2,2,2,2,2,2,2,2,2,2,2,2,2,2, /* U+0080 to U+03FF */
133 /* 0xD0 */ 2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2, /* U+0400 to U+07FF */
134 /* 0xE0 */ 3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3, /* U+0800 to U+FFFF */
135 /* 0xF0 */ 4,4,4,4,4,4,4,4,5,5,5,5,6,6,	    /* above BMP to 2**31 - 1 */
136            /* Perl extended (never was official UTF-8).  Up to 36 bit */
137 /* 0xFE */                             7,
138            /* More extended, Up to 72 bits (64-bit + reserved) */
139 /* 0xFF */                               UTF8_MAXBYTES
140 };
141 #else
142 EXTCONST unsigned char PL_utf8skip[];
143 #endif
144 
145 END_EXTERN_C
146 
147 /*
148 
149 =for apidoc Am|U8|NATIVE_TO_LATIN1|U8 ch
150 
151 Returns the Latin-1 (including ASCII and control characters) equivalent of the
152 input native code point given by C<ch>.  Thus, C<NATIVE_TO_LATIN1(193)> on
153 EBCDIC platforms returns 65.  These each represent the character C<"A"> on
154 their respective platforms.  On ASCII platforms no conversion is needed, so
155 this macro expands to just its input, adding no time nor space requirements to
156 the implementation.
157 
158 For conversion of code points potentially larger than will fit in a character,
159 use L</NATIVE_TO_UNI>.
160 
161 =for apidoc Am|U8|LATIN1_TO_NATIVE|U8 ch
162 
163 Returns the native  equivalent of the input Latin-1 code point (including ASCII
164 and control characters) given by C<ch>.  Thus, C<LATIN1_TO_NATIVE(66)> on
165 EBCDIC platforms returns 194.  These each represent the character C<"B"> on
166 their respective platforms.  On ASCII platforms no conversion is needed, so
167 this macro expands to just its input, adding no time nor space requirements to
168 the implementation.
169 
170 For conversion of code points potentially larger than will fit in a character,
171 use L</UNI_TO_NATIVE>.
172 
173 =for apidoc Am|UV|NATIVE_TO_UNI|UV ch
174 
175 Returns the Unicode  equivalent of the input native code point given by C<ch>.
176 Thus, C<NATIVE_TO_UNI(195)> on EBCDIC platforms returns 67.  These each
177 represent the character C<"C"> on their respective platforms.  On ASCII
178 platforms no conversion is needed, so this macro expands to just its input,
179 adding no time nor space requirements to the implementation.
180 
181 =for apidoc Am|UV|UNI_TO_NATIVE|UV ch
182 
183 Returns the native  equivalent of the input Unicode code point  given by C<ch>.
184 Thus, C<UNI_TO_NATIVE(68)> on EBCDIC platforms returns 196.  These each
185 represent the character C<"D"> on their respective platforms.  On ASCII
186 platforms no conversion is needed, so this macro expands to just its input,
187 adding no time nor space requirements to the implementation.
188 
189 =cut
190 */
191 
192 #define NATIVE_TO_LATIN1(ch)     (__ASSERT_(FITS_IN_8_BITS(ch)) ((U8) ((ch) | 0)))
193 #define LATIN1_TO_NATIVE(ch)     (__ASSERT_(FITS_IN_8_BITS(ch)) ((U8) ((ch) | 0)))
194 
195 /* I8 is an intermediate version of UTF-8 used only in UTF-EBCDIC.  We thus
196  * consider it to be identical to UTF-8 on ASCII platforms.  Strictly speaking
197  * UTF-8 and UTF-EBCDIC are two different things, but we often conflate them
198  * because they are 8-bit encodings that serve the same purpose in Perl, and
199  * rarely do we need to distinguish them.  The term "NATIVE_UTF8" applies to
200  * whichever one is applicable on the current platform */
201 #define NATIVE_UTF8_TO_I8(ch) (__ASSERT_(FITS_IN_8_BITS(ch)) ((U8) ((ch) | 0)))
202 #define I8_TO_NATIVE_UTF8(ch) (__ASSERT_(FITS_IN_8_BITS(ch)) ((U8) ((ch) | 0)))
203 
204 #define UNI_TO_NATIVE(ch)        ((UV) ((ch) | 0))
205 #define NATIVE_TO_UNI(ch)        ((UV) ((ch) | 0))
206 
207 /*
208 
209  The following table is from Unicode 3.2, plus the Perl extensions for above
210  U+10FFFF
211 
212  Code Points		1st Byte  2nd Byte  3rd    4th     5th     6th       7th   8th-13th
213 
214    U+0000..U+007F	00..7F
215    U+0080..U+07FF     * C2..DF    80..BF
216    U+0800..U+0FFF	E0      * A0..BF  80..BF
217    U+1000..U+CFFF       E1..EC    80..BF  80..BF
218    U+D000..U+D7FF       ED        80..9F  80..BF
219    U+D800..U+DFFF       ED        A0..BF  80..BF  (surrogates)
220    U+E000..U+FFFF       EE..EF    80..BF  80..BF
221   U+10000..U+3FFFF	F0      * 90..BF  80..BF  80..BF
222   U+40000..U+FFFFF	F1..F3    80..BF  80..BF  80..BF
223  U+100000..U+10FFFF	F4        80..8F  80..BF  80..BF
224     Below are above-Unicode code points
225  U+110000..U+13FFFF	F4        90..BF  80..BF  80..BF
226  U+110000..U+1FFFFF	F5..F7    80..BF  80..BF  80..BF
227  U+200000..U+FFFFFF     F8      * 88..BF  80..BF  80..BF  80..BF
228 U+1000000..U+3FFFFFF    F9..FB    80..BF  80..BF  80..BF  80..BF
229 U+4000000..U+3FFFFFFF    FC     * 84..BF  80..BF  80..BF  80..BF  80..BF
230 U+40000000..U+7FFFFFFF   FD       80..BF  80..BF  80..BF  80..BF  80..BF
231 U+80000000..U+FFFFFFFFF  FE     * 82..BF  80..BF  80..BF  80..BF  80..BF    80..BF
232 U+1000000000..           FF       80..BF  80..BF  80..BF  80..BF  80..BF  * 81..BF  80..BF
233 
234 Note the gaps before several of the byte entries above marked by '*'.  These are
235 caused by legal UTF-8 avoiding non-shortest encodings: it is technically
236 possible to UTF-8-encode a single code point in different ways, but that is
237 explicitly forbidden, and the shortest possible encoding should always be used
238 (and that is what Perl does).  The non-shortest ones are called 'overlongs'.
239 
240  */
241 
242 /*
243  Another way to look at it, as bits:
244 
245                   Code Points      1st Byte   2nd Byte   3rd Byte   4th Byte
246 
247                         0aaa aaaa  0aaa aaaa
248               0000 0bbb bbaa aaaa  110b bbbb  10aa aaaa
249               cccc bbbb bbaa aaaa  1110 cccc  10bb bbbb  10aa aaaa
250  00 000d ddcc cccc bbbb bbaa aaaa  1111 0ddd  10cc cccc  10bb bbbb  10aa aaaa
251 
252 As you can see, the continuation bytes all begin with C<10>, and the
253 leading bits of the start byte tell how many bytes there are in the
254 encoded character.
255 
256 Perl's extended UTF-8 means we can have start bytes up through FF, though any
257 beginning with FF yields a code point that is too large for 32-bit ASCII
258 platforms.  FF signals to use 13 bytes for the encoded character.  This breaks
259 the paradigm that the number of leading bits gives how many total bytes there
260 are in the character. */
261 
262 /* This is the number of low-order bits a continuation byte in a UTF-8 encoded
263  * sequence contributes to the specification of the code point.  In the bit
264  * maps above, you see that the first 2 bits are a constant '10', leaving 6 of
265  * real information */
266 #define UTF_ACCUMULATION_SHIFT		6
267 
268 /* ^? is defined to be DEL on ASCII systems.  See the definition of toCTRL()
269  * for more */
270 #define QUESTION_MARK_CTRL  DEL_NATIVE
271 
272 /* Surrogates, non-character code points and above-Unicode code points are
273  * problematic in some contexts.  This allows code that needs to check for
274  * those to quickly exclude the vast majority of code points it will
275  * encounter */
276 #define isUTF8_POSSIBLY_PROBLEMATIC(c) (__ASSERT_(FITS_IN_8_BITS(c))        \
277                                         (U8) c >= 0xED)
278 
279 #define UNICODE_IS_PERL_EXTENDED(uv)    UNLIKELY((UV) (uv) > 0x7FFFFFFF)
280 
281 #endif /* EBCDIC vs ASCII */
282 
283 /* 2**UTF_ACCUMULATION_SHIFT - 1.  This masks out all but the bits that carry
284  * real information in a continuation byte.  This turns out to be 0x3F in
285  * UTF-8, 0x1F in UTF-EBCDIC. */
286 #define UTF_CONTINUATION_MASK  ((U8) ((1U << UTF_ACCUMULATION_SHIFT) - 1))
287 
288 /* For use in UTF8_IS_CONTINUATION().  This turns out to be 0xC0 in UTF-8,
289  * E0 in UTF-EBCDIC */
290 #define UTF_IS_CONTINUATION_MASK    ((U8) (0xFF << UTF_ACCUMULATION_SHIFT))
291 
292 /* This defines the bits that are to be in the continuation bytes of a
293  * multi-byte UTF-8 encoded character that mark it is a continuation byte.
294  * This turns out to be 0x80 in UTF-8, 0xA0 in UTF-EBCDIC.  (khw doesn't know
295  * the underlying reason that B0 works here) */
296 #define UTF_CONTINUATION_MARK       (UTF_IS_CONTINUATION_MASK & 0xB0)
297 
298 /* Is the byte 'c' part of a multi-byte UTF8-8 encoded sequence, and not the
299  * first byte thereof? */
300 #define UTF8_IS_CONTINUATION(c)     (__ASSERT_(FITS_IN_8_BITS(c))           \
301             (((NATIVE_UTF8_TO_I8(c) & UTF_IS_CONTINUATION_MASK)             \
302                                                 == UTF_CONTINUATION_MARK)))
303 
304 /* Is the representation of the Unicode code point 'cp' the same regardless of
305  * being encoded in UTF-8 or not? This is a fundamental property of
306  * UTF-8,EBCDIC */
307 #define OFFUNI_IS_INVARIANT(c) (((WIDEST_UTYPE)(c)) < UTF_CONTINUATION_MARK)
308 
309 /*
310 =for apidoc Am|bool|UVCHR_IS_INVARIANT|UV cp
311 
312 Evaluates to 1 if the representation of code point C<cp> is the same whether or
313 not it is encoded in UTF-8; otherwise evaluates to 0.  UTF-8 invariant
314 characters can be copied as-is when converting to/from UTF-8, saving time.
315 C<cp> is Unicode if above 255; otherwise is platform-native.
316 
317 =cut
318  */
319 #if defined(__m88k__)
320 /* XXX workaround: m88k gcc3 produces wrong code with NATIVE_TO_UNI() */
321 #define UVCHR_IS_INVARIANT(cp)  (OFFUNI_IS_INVARIANT(cp))
322 #else	/* the original one */
323 #define UVCHR_IS_INVARIANT(cp)  (OFFUNI_IS_INVARIANT(NATIVE_TO_UNI(cp)))
324 #endif
325 
326 /* Internal macro to be used only in this file to aid in constructing other
327  * publicly accessible macros.
328  * The number of bytes required to express this uv in UTF-8, for just those
329  * uv's requiring 2 through 6 bytes, as these are common to all platforms and
330  * word sizes.  The number of bytes needed is given by the number of leading 1
331  * bits in the start byte.  There are 32 start bytes that have 2 initial 1 bits
332  * (C0-DF); there are 16 that have 3 initial 1 bits (E0-EF); 8 that have 4
333  * initial 1 bits (F0-F8); 4 that have 5 initial 1 bits (F9-FB), and 2 that
334  * have 6 initial 1 bits (FC-FD).  The largest number a string of n bytes can
335  * represent is       (the number of possible start bytes for 'n')
336  *                  * (the number of possiblities for each start byte
337  * The latter in turn is
338  *                  2  ** (  (how many continuation bytes there are)
339  *                         * (the number of bits of information each
340  *                            continuation byte holds))
341  *
342  * If we were on a platform where we could use a fast find first set bit
343  * instruction (or count leading zeros instruction) this could be replaced by
344  * using that to find the log2 of the uv, and divide that by the number of bits
345  * of information in each continuation byte, adjusting for large cases and how
346  * much information is in a start byte for that length */
347 #define __COMMON_UNI_SKIP(uv)                                               \
348           (UV) (uv) < (32 * (1U << (    UTF_ACCUMULATION_SHIFT))) ? 2 :     \
349           (UV) (uv) < (16 * (1U << (2 * UTF_ACCUMULATION_SHIFT))) ? 3 :     \
350           (UV) (uv) < ( 8 * (1U << (3 * UTF_ACCUMULATION_SHIFT))) ? 4 :     \
351           (UV) (uv) < ( 4 * (1U << (4 * UTF_ACCUMULATION_SHIFT))) ? 5 :     \
352           (UV) (uv) < ( 2 * (1U << (5 * UTF_ACCUMULATION_SHIFT))) ? 6 :
353 
354 /* Internal macro to be used only in this file.
355  * This adds to __COMMON_UNI_SKIP the details at this platform's upper range.
356  * For any-sized EBCDIC platforms, or 64-bit ASCII ones, we need one more test
357  * to see if just 7 bytes is needed, or if the maximum is needed.  For 32-bit
358  * ASCII platforms, everything is representable by 7 bytes */
359 #if defined(UV_IS_QUAD) || defined(EBCDIC)
360 #   define __BASE_UNI_SKIP(uv) (__COMMON_UNI_SKIP(uv)                       \
361      (UV) (uv) < ((UV) 1U << (6 * UTF_ACCUMULATION_SHIFT)) ? 7 : UTF8_MAXBYTES)
362 #else
363 #   define __BASE_UNI_SKIP(uv) (__COMMON_UNI_SKIP(uv) 7)
364 #endif
365 
366 /* The next two macros use the base macro defined above, and add in the tests
367  * at the low-end of the range, for just 1 byte, yielding complete macros,
368  * publicly accessible. */
369 
370 /* Input is a true Unicode (not-native) code point */
371 #define OFFUNISKIP(uv) (OFFUNI_IS_INVARIANT(uv) ? 1 : __BASE_UNI_SKIP(uv))
372 
373 /*
374 
375 =for apidoc Am|STRLEN|UVCHR_SKIP|UV cp
376 returns the number of bytes required to represent the code point C<cp> when
377 encoded as UTF-8.  C<cp> is a native (ASCII or EBCDIC) code point if less than
378 255; a Unicode code point otherwise.
379 
380 =cut
381  */
382 #define UVCHR_SKIP(uv) ( UVCHR_IS_INVARIANT(uv) ? 1 : __BASE_UNI_SKIP(uv))
383 
384 #define UTF_MIN_START_BYTE                                                  \
385      ((UTF_CONTINUATION_MARK >> UTF_ACCUMULATION_SHIFT) | UTF_START_MARK(2))
386 
387 /* Is the byte 'c' the first byte of a multi-byte UTF8-8 encoded sequence?
388  * This excludes invariants (they are single-byte).  It also excludes the
389  * illegal overlong sequences that begin with C0 and C1 on ASCII platforms, and
390  * C0-C4 I8 start bytes on EBCDIC ones.  On EBCDIC E0 can't start a
391  * non-overlong sequence, so we define a base macro and for those platforms,
392  * extend it to also exclude E0 */
393 #define UTF8_IS_START_base(c)    (__ASSERT_(FITS_IN_8_BITS(c))              \
394                              (NATIVE_UTF8_TO_I8(c) >= UTF_MIN_START_BYTE))
395 #ifdef EBCDIC
396 #  define UTF8_IS_START(c)                                                  \
397                 (UTF8_IS_START_base(c) && (c) != I8_TO_NATIVE_UTF8(0xE0))
398 #else
399 #  define UTF8_IS_START(c)  UTF8_IS_START_base(c)
400 #endif
401 
402 #define UTF_MIN_ABOVE_LATIN1_BYTE                                           \
403                     ((0x100 >> UTF_ACCUMULATION_SHIFT) | UTF_START_MARK(2))
404 
405 /* Is the UTF8-encoded byte 'c' the first byte of a sequence of bytes that
406  * represent a code point > 255? */
407 #define UTF8_IS_ABOVE_LATIN1(c)     (__ASSERT_(FITS_IN_8_BITS(c))           \
408                         (NATIVE_UTF8_TO_I8(c) >= UTF_MIN_ABOVE_LATIN1_BYTE))
409 
410 /* Is the UTF8-encoded byte 'c' the first byte of a two byte sequence?  Use
411  * UTF8_IS_NEXT_CHAR_DOWNGRADEABLE() instead if the input isn't known to
412  * be well-formed. */
413 #define UTF8_IS_DOWNGRADEABLE_START(c)	(__ASSERT_(FITS_IN_8_BITS(c))       \
414                 inRANGE(NATIVE_UTF8_TO_I8(c),                               \
415                         UTF_MIN_START_BYTE, UTF_MIN_ABOVE_LATIN1_BYTE - 1))
416 
417 /* The largest code point representable by two UTF-8 bytes on this platform.
418  * As explained in the comments for __COMMON_UNI_SKIP, 32 start bytes with
419  * UTF_ACCUMULATION_SHIFT bits of information each */
420 #define MAX_UTF8_TWO_BYTE (32 * (1U << UTF_ACCUMULATION_SHIFT) - 1)
421 
422 /* The largest code point representable by two UTF-8 bytes on any platform that
423  * Perl runs on.  This value is constrained by EBCDIC which has 5 bits per
424  * continuation byte */
425 #define MAX_PORTABLE_UTF8_TWO_BYTE (32 * (1U << 5) - 1)
426 
427 /*
428 
429 =for apidoc AmnU|STRLEN|UTF8_MAXBYTES_CASE
430 
431 The maximum number of UTF-8 bytes a single Unicode character can
432 uppercase/lowercase/titlecase/fold into.
433 
434 =cut
435 
436  * Unicode guarantees that the maximum expansion is UTF8_MAX_FOLD_CHAR_EXPAND
437  * characters, but any above-Unicode code point will fold to itself, so we only
438  * have to look at the expansion of the maximum Unicode code point.  But this
439  * number may be less than the space occupied by a very large code point under
440  * Perl's extended UTF-8.  We have to make it large enough to fit any single
441  * character.  (It turns out that ASCII and EBCDIC differ in which is larger)
442  *
443 =cut
444 */
445 #define UTF8_MAXBYTES_CASE	                                                \
446             MAX(UTF8_MAXBYTES, UTF8_MAX_FOLD_CHAR_EXPAND * OFFUNISKIP(0x10FFFF))
447 
448 /* Rest of these are attributes of Unicode and perl's internals rather than the
449  * encoding, or happen to be the same in both ASCII and EBCDIC (at least at
450  * this level; the macros that some of these call may have different
451  * definitions in the two encodings */
452 
453 /* In domain restricted to ASCII, these may make more sense to the reader than
454  * the ones with Latin1 in the name */
455 #define NATIVE_TO_ASCII(ch)      NATIVE_TO_LATIN1(ch)
456 #define ASCII_TO_NATIVE(ch)      LATIN1_TO_NATIVE(ch)
457 
458 /* More or less misleadingly-named defines, retained for back compat */
459 #define NATIVE_TO_UTF(ch)        NATIVE_UTF8_TO_I8(ch)
460 #define NATIVE_TO_I8(ch)         NATIVE_UTF8_TO_I8(ch)
461 #define UTF_TO_NATIVE(ch)        I8_TO_NATIVE_UTF8(ch)
462 #define I8_TO_NATIVE(ch)         I8_TO_NATIVE_UTF8(ch)
463 #define NATIVE8_TO_UNI(ch)       NATIVE_TO_LATIN1(ch)
464 
465 /* This defines the 1-bits that are to be in the first byte of a multi-byte
466  * UTF-8 encoded character that mark it as a start byte and give the number of
467  * bytes that comprise the character. 'len' is the number of bytes in the
468  * multi-byte sequence. */
469 #define UTF_START_MARK(len) (((len) >  7) ? 0xFF : ((U8) (0xFE << (7-(len)))))
470 
471 /* Masks out the initial one bits in a start byte, leaving the real data ones.
472  * Doesn't work on an invariant byte.  'len' is the number of bytes in the
473  * multi-byte sequence that comprises the character. */
474 #define UTF_START_MASK(len) (((len) >= 7) ? 0x00 : (0x1F >> ((len)-2)))
475 
476 /* Adds a UTF8 continuation byte 'new' of information to a running total code
477  * point 'old' of all the continuation bytes so far.  This is designed to be
478  * used in a loop to convert from UTF-8 to the code point represented.  Note
479  * that this is asymmetric on EBCDIC platforms, in that the 'new' parameter is
480  * the UTF-EBCDIC byte, whereas the 'old' parameter is a Unicode (not EBCDIC)
481  * code point in process of being generated */
482 #define UTF8_ACCUMULATE(old, new) (__ASSERT_(FITS_IN_8_BITS(new))              \
483                                    ((old) << UTF_ACCUMULATION_SHIFT)           \
484                                    | ((NATIVE_UTF8_TO_I8(new))                 \
485                                        & UTF_CONTINUATION_MASK))
486 
487 /* This works in the face of malformed UTF-8. */
488 #define UTF8_IS_NEXT_CHAR_DOWNGRADEABLE(s, e)                                 \
489                                        (   UTF8_IS_DOWNGRADEABLE_START(*(s))  \
490                                         && ( (e) - (s) > 1)                   \
491                                         && UTF8_IS_CONTINUATION(*((s)+1)))
492 
493 /* Number of bytes a code point occupies in UTF-8. */
494 #define NATIVE_SKIP(uv) UVCHR_SKIP(uv)
495 
496 /* Most code which says UNISKIP is really thinking in terms of native code
497  * points (0-255) plus all those beyond.  This is an imprecise term, but having
498  * it means existing code continues to work.  For precision, use UVCHR_SKIP,
499  * NATIVE_SKIP, or OFFUNISKIP */
500 #define UNISKIP(uv)   UVCHR_SKIP(uv)
501 
502 /* Longer, but more accurate name */
503 #define UTF8_IS_ABOVE_LATIN1_START(c)     UTF8_IS_ABOVE_LATIN1(c)
504 
505 /* Convert a UTF-8 variant Latin1 character to a native code point value.
506  * Needs just one iteration of accumulate.  Should be used only if it is known
507  * that the code point is < 256, and is not UTF-8 invariant.  Use the slower
508  * but more general TWO_BYTE_UTF8_TO_NATIVE() which handles any code point
509  * representable by two bytes (which turns out to be up through
510  * MAX_PORTABLE_UTF8_TWO_BYTE).  The two parameters are:
511  *  HI: a downgradable start byte;
512  *  LO: continuation.
513  * */
514 #define EIGHT_BIT_UTF8_TO_NATIVE(HI, LO)                                        \
515     ( __ASSERT_(UTF8_IS_DOWNGRADEABLE_START(HI))                                \
516       __ASSERT_(UTF8_IS_CONTINUATION(LO))                                       \
517      LATIN1_TO_NATIVE(UTF8_ACCUMULATE((                                         \
518                             NATIVE_UTF8_TO_I8(HI) & UTF_START_MASK(2)), (LO))))
519 
520 /* Convert a two (not one) byte utf8 character to a native code point value.
521  * Needs just one iteration of accumulate.  Should not be used unless it is
522  * known that the two bytes are legal: 1) two-byte start, and 2) continuation.
523  * Note that the result can be larger than 255 if the input character is not
524  * downgradable */
525 #define TWO_BYTE_UTF8_TO_NATIVE(HI, LO) \
526     (__ASSERT_(FITS_IN_8_BITS(HI))                                              \
527      __ASSERT_(FITS_IN_8_BITS(LO))                                              \
528      __ASSERT_(PL_utf8skip[HI] == 2)                                            \
529      __ASSERT_(UTF8_IS_CONTINUATION(LO))                                        \
530      UNI_TO_NATIVE(UTF8_ACCUMULATE((NATIVE_UTF8_TO_I8(HI) & UTF_START_MASK(2)), \
531                                    (LO))))
532 
533 /* Should never be used, and be deprecated */
534 #define TWO_BYTE_UTF8_TO_UNI(HI, LO) NATIVE_TO_UNI(TWO_BYTE_UTF8_TO_NATIVE(HI, LO))
535 
536 /*
537 
538 =for apidoc Am|STRLEN|UTF8SKIP|char* s
539 returns the number of bytes a non-malformed UTF-8 encoded character whose first
540 (perhaps only) byte is pointed to by C<s>.
541 
542 If there is a possibility of malformed input, use instead:
543 
544 =over
545 
546 =item L</C<UTF8_SAFE_SKIP>> if you know the maximum ending pointer in the
547 buffer pointed to by C<s>; or
548 
549 =item L</C<UTF8_CHK_SKIP>> if you don't know it.
550 
551 =back
552 
553 It is better to restructure your code so the end pointer is passed down so that
554 you know what it actually is at the point of this call, but if that isn't
555 possible, L</C<UTF8_CHK_SKIP>> can minimize the chance of accessing beyond the end
556 of the input buffer.
557 
558 =cut
559  */
560 #define UTF8SKIP(s)  PL_utf8skip[*(const U8*)(s)]
561 
562 /*
563 =for apidoc Am|STRLEN|UTF8_SKIP|char* s
564 This is a synonym for L</C<UTF8SKIP>>
565 
566 =cut
567 */
568 
569 #define UTF8_SKIP(s) UTF8SKIP(s)
570 
571 /*
572 =for apidoc Am|STRLEN|UTF8_CHK_SKIP|char* s
573 
574 This is a safer version of L</C<UTF8SKIP>>, but still not as safe as
575 L</C<UTF8_SAFE_SKIP>>.  This version doesn't blindly assume that the input
576 string pointed to by C<s> is well-formed, but verifies that there isn't a NUL
577 terminating character before the expected end of the next character in C<s>.
578 The length C<UTF8_CHK_SKIP> returns stops just before any such NUL.
579 
580 Perl tends to add NULs, as an insurance policy, after the end of strings in
581 SV's, so it is likely that using this macro will prevent inadvertent reading
582 beyond the end of the input buffer, even if it is malformed UTF-8.
583 
584 This macro is intended to be used by XS modules where the inputs could be
585 malformed, and it isn't feasible to restructure to use the safer
586 L</C<UTF8_SAFE_SKIP>>, for example when interfacing with a C library.
587 
588 =cut
589 */
590 
591 #define UTF8_CHK_SKIP(s)                                                       \
592             (s[0] == '\0' ? 1 : MIN(UTF8SKIP(s),                               \
593                                     my_strnlen((char *) (s), UTF8SKIP(s))))
594 /*
595 
596 =for apidoc Am|STRLEN|UTF8_SAFE_SKIP|char* s|char* e
597 returns 0 if S<C<s E<gt>= e>>; otherwise returns the number of bytes in the
598 UTF-8 encoded character whose first  byte is pointed to by C<s>.  But it never
599 returns beyond C<e>.  On DEBUGGING builds, it asserts that S<C<s E<lt>= e>>.
600 
601 =cut
602  */
603 #define UTF8_SAFE_SKIP(s, e)  (__ASSERT_((e) >= (s))                \
604                               ((e) - (s)) <= 0                      \
605                                ? 0                                  \
606                                : MIN(((e) - (s)), UTF8_SKIP(s)))
607 
608 /* Most code that says 'UNI_' really means the native value for code points up
609  * through 255 */
610 #define UNI_IS_INVARIANT(cp)   UVCHR_IS_INVARIANT(cp)
611 
612 /*
613 =for apidoc Am|bool|UTF8_IS_INVARIANT|char c
614 
615 Evaluates to 1 if the byte C<c> represents the same character when encoded in
616 UTF-8 as when not; otherwise evaluates to 0.  UTF-8 invariant characters can be
617 copied as-is when converting to/from UTF-8, saving time.
618 
619 In spite of the name, this macro gives the correct result if the input string
620 from which C<c> comes is not encoded in UTF-8.
621 
622 See C<L</UVCHR_IS_INVARIANT>> for checking if a UV is invariant.
623 
624 =cut
625 
626 The reason it works on both UTF-8 encoded strings and non-UTF-8 encoded, is
627 that it returns TRUE in each for the exact same set of bit patterns.  It is
628 valid on a subset of what UVCHR_IS_INVARIANT is valid on, so can just use that;
629 and the compiler should optimize out anything extraneous given the
630 implementation of the latter.  The |0 makes sure this isn't mistakenly called
631 with a ptr argument.
632 */
633 #define UTF8_IS_INVARIANT(c)	UVCHR_IS_INVARIANT((c) | 0)
634 
635 /* Like the above, but its name implies a non-UTF8 input, which as the comments
636  * above show, doesn't matter as to its implementation */
637 #define NATIVE_BYTE_IS_INVARIANT(c)	UVCHR_IS_INVARIANT(c)
638 
639 /* Misleadingly named: is the UTF8-encoded byte 'c' part of a variant sequence
640  * in UTF-8?  This is the inverse of UTF8_IS_INVARIANT. */
641 #define UTF8_IS_CONTINUED(c)  (__ASSERT_(FITS_IN_8_BITS(c))                 \
642                                (! UTF8_IS_INVARIANT(c)))
643 
644 /* The macros in the next 4 sets are used to generate the two utf8 or utfebcdic
645  * bytes from an ordinal that is known to fit into exactly two (not one) bytes;
646  * it must be less than 0x3FF to work across both encodings. */
647 
648 /* These two are helper macros for the other three sets, and should not be used
649  * directly anywhere else.  'translate_function' is either NATIVE_TO_LATIN1
650  * (which works for code points up through 0xFF) or NATIVE_TO_UNI which works
651  * for any code point */
652 #define __BASE_TWO_BYTE_HI(c, translate_function)                               \
653            (__ASSERT_(! UVCHR_IS_INVARIANT(c))                                  \
654             I8_TO_NATIVE_UTF8((translate_function(c) >> UTF_ACCUMULATION_SHIFT) \
655                               | UTF_START_MARK(2)))
656 #define __BASE_TWO_BYTE_LO(c, translate_function)                               \
657              (__ASSERT_(! UVCHR_IS_INVARIANT(c))                                \
658               I8_TO_NATIVE_UTF8((translate_function(c) & UTF_CONTINUATION_MASK) \
659                                  | UTF_CONTINUATION_MARK))
660 
661 /* The next two macros should not be used.  They were designed to be usable as
662  * the case label of a switch statement, but this doesn't work for EBCDIC.  Use
663  * regen/unicode_constants.pl instead */
664 #define UTF8_TWO_BYTE_HI_nocast(c)  __BASE_TWO_BYTE_HI(c, NATIVE_TO_UNI)
665 #define UTF8_TWO_BYTE_LO_nocast(c)  __BASE_TWO_BYTE_LO(c, NATIVE_TO_UNI)
666 
667 /* The next two macros are used when the source should be a single byte
668  * character; checked for under DEBUGGING */
669 #define UTF8_EIGHT_BIT_HI(c) (__ASSERT_(FITS_IN_8_BITS(c))                    \
670                              ( __BASE_TWO_BYTE_HI(c, NATIVE_TO_LATIN1)))
671 #define UTF8_EIGHT_BIT_LO(c) (__ASSERT_(FITS_IN_8_BITS(c))                    \
672                              (__BASE_TWO_BYTE_LO(c, NATIVE_TO_LATIN1)))
673 
674 /* These final two macros in the series are used when the source can be any
675  * code point whose UTF-8 is known to occupy 2 bytes; they are less efficient
676  * than the EIGHT_BIT versions on EBCDIC platforms.  We use the logical '~'
677  * operator instead of "<=" to avoid getting compiler warnings.
678  * MAX_UTF8_TWO_BYTE should be exactly all one bits in the lower few
679  * places, so the ~ works */
680 #define UTF8_TWO_BYTE_HI(c)                                                    \
681        (__ASSERT_((sizeof(c) ==  1)                                            \
682                   || !(((WIDEST_UTYPE)(c)) & ~MAX_UTF8_TWO_BYTE))              \
683         (__BASE_TWO_BYTE_HI(c, NATIVE_TO_UNI)))
684 #define UTF8_TWO_BYTE_LO(c)                                                    \
685        (__ASSERT_((sizeof(c) ==  1)                                            \
686                   || !(((WIDEST_UTYPE)(c)) & ~MAX_UTF8_TWO_BYTE))              \
687         (__BASE_TWO_BYTE_LO(c, NATIVE_TO_UNI)))
688 
689 /* This is illegal in any well-formed UTF-8 in both EBCDIC and ASCII
690  * as it is only in overlongs. */
691 #define ILLEGAL_UTF8_BYTE   I8_TO_NATIVE_UTF8(0xC1)
692 
693 /*
694  * 'UTF' is whether or not p is encoded in UTF8.  The names 'foo_lazy_if' stem
695  * from an earlier version of these macros in which they didn't call the
696  * foo_utf8() macros (i.e. were 'lazy') unless they decided that *p is the
697  * beginning of a utf8 character.  Now that foo_utf8() determines that itself,
698  * no need to do it again here
699  */
700 #define isIDFIRST_lazy_if_safe(p, e, UTF)                                   \
701                    ((IN_BYTES || !UTF)                                      \
702                      ? isIDFIRST(*(p))                                      \
703                      : isIDFIRST_utf8_safe(p, e))
704 #define isWORDCHAR_lazy_if_safe(p, e, UTF)                                  \
705                    ((IN_BYTES || !UTF)                                      \
706                      ? isWORDCHAR(*(p))                                     \
707                      : isWORDCHAR_utf8_safe((U8 *) p, (U8 *) e))
708 #define isALNUM_lazy_if_safe(p, e, UTF) isWORDCHAR_lazy_if_safe(p, e, UTF)
709 
710 #define UTF8_MAXLEN UTF8_MAXBYTES
711 
712 /* A Unicode character can fold to up to 3 characters */
713 #define UTF8_MAX_FOLD_CHAR_EXPAND 3
714 
715 #define IN_BYTES UNLIKELY(CopHINTS_get(PL_curcop) & HINT_BYTES)
716 
717 /*
718 
719 =for apidoc Am|bool|DO_UTF8|SV* sv
720 Returns a bool giving whether or not the PV in C<sv> is to be treated as being
721 encoded in UTF-8.
722 
723 You should use this I<after> a call to C<SvPV()> or one of its variants, in
724 case any call to string overloading updates the internal UTF-8 encoding flag.
725 
726 =cut
727 */
728 #define DO_UTF8(sv) (SvUTF8(sv) && !IN_BYTES)
729 
730 /* Should all strings be treated as Unicode, and not just UTF-8 encoded ones?
731  * Is so within 'feature unicode_strings' or 'locale :not_characters', and not
732  * within 'use bytes'.  UTF-8 locales are not tested for here, but perhaps
733  * could be */
734 #define IN_UNI_8_BIT                                                    \
735 	    ((    (      (CopHINTS_get(PL_curcop) & HINT_UNI_8_BIT))    \
736                    || (   CopHINTS_get(PL_curcop) & HINT_LOCALE_PARTIAL \
737                             /* -1 below is for :not_characters */       \
738                        && _is_in_locale_category(FALSE, -1)))           \
739               && (! IN_BYTES))
740 
741 
742 #define UTF8_ALLOW_EMPTY		0x0001	/* Allow a zero length string */
743 #define UTF8_GOT_EMPTY                  UTF8_ALLOW_EMPTY
744 
745 /* Allow first byte to be a continuation byte */
746 #define UTF8_ALLOW_CONTINUATION		0x0002
747 #define UTF8_GOT_CONTINUATION		UTF8_ALLOW_CONTINUATION
748 
749 /* Unexpected non-continuation byte */
750 #define UTF8_ALLOW_NON_CONTINUATION	0x0004
751 #define UTF8_GOT_NON_CONTINUATION	UTF8_ALLOW_NON_CONTINUATION
752 
753 /* expecting more bytes than were available in the string */
754 #define UTF8_ALLOW_SHORT		0x0008
755 #define UTF8_GOT_SHORT		        UTF8_ALLOW_SHORT
756 
757 /* Overlong sequence; i.e., the code point can be specified in fewer bytes.
758  * First one will convert the overlong to the REPLACEMENT CHARACTER; second
759  * will return what the overlong evaluates to */
760 #define UTF8_ALLOW_LONG                 0x0010
761 #define UTF8_ALLOW_LONG_AND_ITS_VALUE   (UTF8_ALLOW_LONG|0x0020)
762 #define UTF8_GOT_LONG                   UTF8_ALLOW_LONG
763 
764 #define UTF8_ALLOW_OVERFLOW             0x0080
765 #define UTF8_GOT_OVERFLOW               UTF8_ALLOW_OVERFLOW
766 
767 #define UTF8_DISALLOW_SURROGATE		0x0100	/* Unicode surrogates */
768 #define UTF8_GOT_SURROGATE		UTF8_DISALLOW_SURROGATE
769 #define UTF8_WARN_SURROGATE		0x0200
770 
771 /* Unicode non-character  code points */
772 #define UTF8_DISALLOW_NONCHAR           0x0400
773 #define UTF8_GOT_NONCHAR                UTF8_DISALLOW_NONCHAR
774 #define UTF8_WARN_NONCHAR               0x0800
775 
776 /* Super-set of Unicode: code points above the legal max */
777 #define UTF8_DISALLOW_SUPER		0x1000
778 #define UTF8_GOT_SUPER		        UTF8_DISALLOW_SUPER
779 #define UTF8_WARN_SUPER		        0x2000
780 
781 /* The original UTF-8 standard did not define UTF-8 with start bytes of 0xFE or
782  * 0xFF, though UTF-EBCDIC did.  This allowed both versions to represent code
783  * points up to 2 ** 31 - 1.  Perl extends UTF-8 so that 0xFE and 0xFF are
784  * usable on ASCII platforms, and 0xFF means something different than
785  * UTF-EBCDIC defines.  These changes allow code points of 64 bits (actually
786  * somewhat more) to be represented on both platforms.  But these are Perl
787  * extensions, and not likely to be interchangeable with other languages.  Note
788  * that on ASCII platforms, FE overflows a signed 32-bit word, and FF an
789  * unsigned one. */
790 #define UTF8_DISALLOW_PERL_EXTENDED     0x4000
791 #define UTF8_GOT_PERL_EXTENDED          UTF8_DISALLOW_PERL_EXTENDED
792 #define UTF8_WARN_PERL_EXTENDED         0x8000
793 
794 /* For back compat, these old names are misleading for overlongs and
795  * UTF_EBCDIC. */
796 #define UTF8_DISALLOW_ABOVE_31_BIT      UTF8_DISALLOW_PERL_EXTENDED
797 #define UTF8_GOT_ABOVE_31_BIT           UTF8_GOT_PERL_EXTENDED
798 #define UTF8_WARN_ABOVE_31_BIT          UTF8_WARN_PERL_EXTENDED
799 #define UTF8_DISALLOW_FE_FF             UTF8_DISALLOW_PERL_EXTENDED
800 #define UTF8_WARN_FE_FF                 UTF8_WARN_PERL_EXTENDED
801 
802 #define UTF8_CHECK_ONLY			0x10000
803 #define _UTF8_NO_CONFIDENCE_IN_CURLEN   0x20000  /* Internal core use only */
804 
805 /* For backwards source compatibility.  They do nothing, as the default now
806  * includes what they used to mean.  The first one's meaning was to allow the
807  * just the single non-character 0xFFFF */
808 #define UTF8_ALLOW_FFFF 0
809 #define UTF8_ALLOW_FE_FF 0
810 #define UTF8_ALLOW_SURROGATE 0
811 
812 /* C9 refers to Unicode Corrigendum #9: allows but discourages non-chars */
813 #define UTF8_DISALLOW_ILLEGAL_C9_INTERCHANGE                                    \
814                                  (UTF8_DISALLOW_SUPER|UTF8_DISALLOW_SURROGATE)
815 #define UTF8_WARN_ILLEGAL_C9_INTERCHANGE (UTF8_WARN_SUPER|UTF8_WARN_SURROGATE)
816 
817 #define UTF8_DISALLOW_ILLEGAL_INTERCHANGE                                       \
818                   (UTF8_DISALLOW_ILLEGAL_C9_INTERCHANGE|UTF8_DISALLOW_NONCHAR)
819 #define UTF8_WARN_ILLEGAL_INTERCHANGE \
820                           (UTF8_WARN_ILLEGAL_C9_INTERCHANGE|UTF8_WARN_NONCHAR)
821 
822 /* This is typically used for code that processes UTF-8 input and doesn't want
823  * to have to deal with any malformations that might be present.  All such will
824  * be safely replaced by the REPLACEMENT CHARACTER, unless other flags
825  * overriding this are also present. */
826 #define UTF8_ALLOW_ANY ( UTF8_ALLOW_CONTINUATION                                \
827                         |UTF8_ALLOW_NON_CONTINUATION                            \
828                         |UTF8_ALLOW_SHORT                                       \
829                         |UTF8_ALLOW_LONG                                        \
830                         |UTF8_ALLOW_OVERFLOW)
831 
832 /* Accept any Perl-extended UTF-8 that evaluates to any UV on the platform, but
833  * not any malformed.  This is the default. */
834 #define UTF8_ALLOW_ANYUV   0
835 #define UTF8_ALLOW_DEFAULT UTF8_ALLOW_ANYUV
836 
837 /*
838 =for apidoc Am|bool|UTF8_IS_SURROGATE|const U8 *s|const U8 *e
839 
840 Evaluates to non-zero if the first few bytes of the string starting at C<s> and
841 looking no further than S<C<e - 1>> are well-formed UTF-8 that represents one
842 of the Unicode surrogate code points; otherwise it evaluates to 0.  If
843 non-zero, the value gives how many bytes starting at C<s> comprise the code
844 point's representation.
845 
846 =cut
847  */
848 #define UTF8_IS_SURROGATE(s, e)      is_SURROGATE_utf8_safe(s, e)
849 
850 
851 #define UTF8_IS_REPLACEMENT(s, send) is_REPLACEMENT_utf8_safe(s,send)
852 
853 #define MAX_LEGAL_CP  ((UV)IV_MAX)
854 
855 /*
856 =for apidoc Am|bool|UTF8_IS_SUPER|const U8 *s|const U8 *e
857 
858 Recall that Perl recognizes an extension to UTF-8 that can encode code
859 points larger than the ones defined by Unicode, which are 0..0x10FFFF.
860 
861 This macro evaluates to non-zero if the first few bytes of the string starting
862 at C<s> and looking no further than S<C<e - 1>> are from this UTF-8 extension;
863 otherwise it evaluates to 0.  If non-zero, the value gives how many bytes
864 starting at C<s> comprise the code point's representation.
865 
866 0 is returned if the bytes are not well-formed extended UTF-8, or if they
867 represent a code point that cannot fit in a UV on the current platform.  Hence
868 this macro can give different results when run on a 64-bit word machine than on
869 one with a 32-bit word size.
870 
871 Note that it is illegal to have code points that are larger than what can
872 fit in an IV on the current machine.
873 
874 =cut
875 
876  *		  ASCII		     EBCDIC I8
877  * U+10FFFF: \xF4\x8F\xBF\xBF	\xF9\xA1\xBF\xBF\xBF	max legal Unicode
878  * U+110000: \xF4\x90\x80\x80	\xF9\xA2\xA0\xA0\xA0
879  * U+110001: \xF4\x90\x80\x81	\xF9\xA2\xA0\xA0\xA1
880  */
881 #ifdef EBCDIC
882 #   define UTF8_IS_SUPER(s, e)                                              \
883                   ((    LIKELY((e) > (s) + 4)                               \
884                     &&      NATIVE_UTF8_TO_I8(*(s)) >= 0xF9                 \
885                     && (    NATIVE_UTF8_TO_I8(*(s)) >  0xF9                 \
886                         || (NATIVE_UTF8_TO_I8(*((s) + 1)) >= 0xA2))         \
887                     &&  LIKELY((s) + UTF8SKIP(s) <= (e)))                   \
888                     ?  is_utf8_char_helper(s, s + UTF8SKIP(s), 0) : 0)
889 #else
890 #   define UTF8_IS_SUPER(s, e)                                              \
891                    ((    LIKELY((e) > (s) + 3)                              \
892                      &&  (*(U8*) (s)) >= 0xF4                               \
893                      && ((*(U8*) (s)) >  0xF4 || (*((U8*) (s) + 1) >= 0x90))\
894                      &&  LIKELY((s) + UTF8SKIP(s) <= (e)))                  \
895                     ?  is_utf8_char_helper(s, s + UTF8SKIP(s), 0) : 0)
896 #endif
897 
898 /* These are now machine generated, and the 'given' clause is no longer
899  * applicable */
900 #define UTF8_IS_NONCHAR_GIVEN_THAT_NON_SUPER_AND_GE_PROBLEMATIC(s, e)          \
901                                             cBOOL(is_NONCHAR_utf8_safe(s,e))
902 
903 /*
904 =for apidoc Am|bool|UTF8_IS_NONCHAR|const U8 *s|const U8 *e
905 
906 Evaluates to non-zero if the first few bytes of the string starting at C<s> and
907 looking no further than S<C<e - 1>> are well-formed UTF-8 that represents one
908 of the Unicode non-character code points; otherwise it evaluates to 0.  If
909 non-zero, the value gives how many bytes starting at C<s> comprise the code
910 point's representation.
911 
912 =for apidoc AmnU|UV|UNICODE_REPLACEMENT
913 
914 Evaluates to 0xFFFD, the code point of the Unicode REPLACEMENT CHARACTER
915 
916 =cut
917  */
918 #define UTF8_IS_NONCHAR(s, e)                                                  \
919                 UTF8_IS_NONCHAR_GIVEN_THAT_NON_SUPER_AND_GE_PROBLEMATIC(s, e)
920 
921 #define UNICODE_SURROGATE_FIRST		0xD800
922 #define UNICODE_SURROGATE_LAST		0xDFFF
923 #define UNICODE_REPLACEMENT		0xFFFD
924 #define UNICODE_BYTE_ORDER_MARK		0xFEFF
925 
926 /* Though our UTF-8 encoding can go beyond this,
927  * let's be conservative and do as Unicode says. */
928 #define PERL_UNICODE_MAX	0x10FFFF
929 
930 #define UNICODE_WARN_SURROGATE         0x0001	/* UTF-16 surrogates */
931 #define UNICODE_WARN_NONCHAR           0x0002	/* Non-char code points */
932 #define UNICODE_WARN_SUPER             0x0004	/* Above 0x10FFFF */
933 #define UNICODE_WARN_PERL_EXTENDED     0x0008	/* Above 0x7FFF_FFFF */
934 #define UNICODE_WARN_ABOVE_31_BIT      UNICODE_WARN_PERL_EXTENDED
935 #define UNICODE_DISALLOW_SURROGATE     0x0010
936 #define UNICODE_DISALLOW_NONCHAR       0x0020
937 #define UNICODE_DISALLOW_SUPER         0x0040
938 #define UNICODE_DISALLOW_PERL_EXTENDED 0x0080
939 
940 #ifdef PERL_CORE
941 #  define UNICODE_ALLOW_ABOVE_IV_MAX   0x0100
942 #endif
943 #define UNICODE_DISALLOW_ABOVE_31_BIT  UNICODE_DISALLOW_PERL_EXTENDED
944 
945 #define UNICODE_GOT_SURROGATE       UNICODE_DISALLOW_SURROGATE
946 #define UNICODE_GOT_NONCHAR         UNICODE_DISALLOW_NONCHAR
947 #define UNICODE_GOT_SUPER           UNICODE_DISALLOW_SUPER
948 #define UNICODE_GOT_PERL_EXTENDED   UNICODE_DISALLOW_PERL_EXTENDED
949 
950 #define UNICODE_WARN_ILLEGAL_C9_INTERCHANGE                                   \
951                                   (UNICODE_WARN_SURROGATE|UNICODE_WARN_SUPER)
952 #define UNICODE_WARN_ILLEGAL_INTERCHANGE                                      \
953                    (UNICODE_WARN_ILLEGAL_C9_INTERCHANGE|UNICODE_WARN_NONCHAR)
954 #define UNICODE_DISALLOW_ILLEGAL_C9_INTERCHANGE                               \
955                           (UNICODE_DISALLOW_SURROGATE|UNICODE_DISALLOW_SUPER)
956 #define UNICODE_DISALLOW_ILLEGAL_INTERCHANGE                                  \
957            (UNICODE_DISALLOW_ILLEGAL_C9_INTERCHANGE|UNICODE_DISALLOW_NONCHAR)
958 
959 /* For backward source compatibility, as are now the default */
960 #define UNICODE_ALLOW_SURROGATE 0
961 #define UNICODE_ALLOW_SUPER	0
962 #define UNICODE_ALLOW_ANY	0
963 
964 /* This matches the 2048 code points between UNICODE_SURROGATE_FIRST (0xD800) and
965  * UNICODE_SURROGATE_LAST (0xDFFF) */
966 #define UNICODE_IS_SURROGATE(uv)        (((UV) (uv) & (~0xFFFF | 0xF800))       \
967                                                                     == 0xD800)
968 
969 #define UNICODE_IS_REPLACEMENT(uv)	((UV) (uv) == UNICODE_REPLACEMENT)
970 #define UNICODE_IS_BYTE_ORDER_MARK(uv)	((UV) (uv) == UNICODE_BYTE_ORDER_MARK)
971 
972 /* Is 'uv' one of the 32 contiguous-range noncharacters? */
973 #define UNICODE_IS_32_CONTIGUOUS_NONCHARS(uv)      ((UV) (uv) >= 0xFDD0         \
974                                                  && (UV) (uv) <= 0xFDEF)
975 
976 /* Is 'uv' one of the 34 plane-ending noncharacters 0xFFFE, 0xFFFF, 0x1FFFE,
977  * 0x1FFFF, ... 0x10FFFE, 0x10FFFF, given that we know that 'uv' is not above
978  * the Unicode legal max */
979 #define UNICODE_IS_END_PLANE_NONCHAR_GIVEN_NOT_SUPER(uv)                        \
980                                               (((UV) (uv) & 0xFFFE) == 0xFFFE)
981 
982 #define UNICODE_IS_NONCHAR(uv)                                                  \
983     (   UNICODE_IS_32_CONTIGUOUS_NONCHARS(uv)                                   \
984      || (   LIKELY( ! UNICODE_IS_SUPER(uv))                                     \
985          && UNICODE_IS_END_PLANE_NONCHAR_GIVEN_NOT_SUPER(uv)))
986 
987 #define UNICODE_IS_SUPER(uv)    ((UV) (uv) > PERL_UNICODE_MAX)
988 
989 #define LATIN_SMALL_LETTER_SHARP_S      LATIN_SMALL_LETTER_SHARP_S_NATIVE
990 #define LATIN_SMALL_LETTER_Y_WITH_DIAERESIS                                  \
991                                 LATIN_SMALL_LETTER_Y_WITH_DIAERESIS_NATIVE
992 #define MICRO_SIGN      MICRO_SIGN_NATIVE
993 #define LATIN_CAPITAL_LETTER_A_WITH_RING_ABOVE                               \
994                             LATIN_CAPITAL_LETTER_A_WITH_RING_ABOVE_NATIVE
995 #define LATIN_SMALL_LETTER_A_WITH_RING_ABOVE                                 \
996                                 LATIN_SMALL_LETTER_A_WITH_RING_ABOVE_NATIVE
997 #define UNICODE_GREEK_CAPITAL_LETTER_SIGMA	0x03A3
998 #define UNICODE_GREEK_SMALL_LETTER_FINAL_SIGMA	0x03C2
999 #define UNICODE_GREEK_SMALL_LETTER_SIGMA	0x03C3
1000 #define GREEK_SMALL_LETTER_MU                   0x03BC
1001 #define GREEK_CAPITAL_LETTER_MU                 0x039C	/* Upper and title case
1002                                                            of MICRON */
1003 #define LATIN_CAPITAL_LETTER_Y_WITH_DIAERESIS   0x0178	/* Also is title case */
1004 #ifdef LATIN_CAPITAL_LETTER_SHARP_S_UTF8
1005 #   define LATIN_CAPITAL_LETTER_SHARP_S	        0x1E9E
1006 #endif
1007 #define LATIN_CAPITAL_LETTER_I_WITH_DOT_ABOVE   0x130
1008 #define LATIN_SMALL_LETTER_DOTLESS_I            0x131
1009 #define LATIN_SMALL_LETTER_LONG_S               0x017F
1010 #define LATIN_SMALL_LIGATURE_LONG_S_T           0xFB05
1011 #define LATIN_SMALL_LIGATURE_ST                 0xFB06
1012 #define KELVIN_SIGN                             0x212A
1013 #define ANGSTROM_SIGN                           0x212B
1014 
1015 #define UNI_DISPLAY_ISPRINT	0x0001
1016 #define UNI_DISPLAY_BACKSLASH	0x0002
1017 #define UNI_DISPLAY_BACKSPACE	0x0004  /* Allow \b when also
1018                                            UNI_DISPLAY_BACKSLASH */
1019 #define UNI_DISPLAY_QQ		(UNI_DISPLAY_ISPRINT                \
1020                                 |UNI_DISPLAY_BACKSLASH              \
1021                                 |UNI_DISPLAY_BACKSPACE)
1022 
1023 /* Character classes could also allow \b, but not patterns in general */
1024 #define UNI_DISPLAY_REGEX	(UNI_DISPLAY_ISPRINT|UNI_DISPLAY_BACKSLASH)
1025 
1026 #define ANYOF_FOLD_SHARP_S(node, input, end)	\
1027 	(ANYOF_BITMAP_TEST(node, LATIN_SMALL_LETTER_SHARP_S) && \
1028 	 (ANYOF_NONBITMAP(node)) && \
1029 	 (ANYOF_FLAGS(node) & ANYOF_LOC_NONBITMAP_FOLD) && \
1030 	 ((end) > (input) + 1) && \
1031 	 isALPHA_FOLD_EQ((input)[0], 's'))
1032 
1033 #define SHARP_S_SKIP 2
1034 
1035 #define is_utf8_char_buf(buf, buf_end) isUTF8_CHAR(buf, buf_end)
1036 #define bytes_from_utf8(s, lenp, is_utf8p)                                  \
1037                             bytes_from_utf8_loc(s, lenp, is_utf8p, 0)
1038 
1039 /*
1040 
1041 =for apidoc Am|STRLEN|isUTF8_CHAR_flags|const U8 *s|const U8 *e| const U32 flags
1042 
1043 Evaluates to non-zero if the first few bytes of the string starting at C<s> and
1044 looking no further than S<C<e - 1>> are well-formed UTF-8, as extended by Perl,
1045 that represents some code point, subject to the restrictions given by C<flags>;
1046 otherwise it evaluates to 0.  If non-zero, the value gives how many bytes
1047 starting at C<s> comprise the code point's representation.  Any bytes remaining
1048 before C<e>, but beyond the ones needed to form the first code point in C<s>,
1049 are not examined.
1050 
1051 If C<flags> is 0, this gives the same results as C<L</isUTF8_CHAR>>;
1052 if C<flags> is C<UTF8_DISALLOW_ILLEGAL_INTERCHANGE>, this gives the same results
1053 as C<L</isSTRICT_UTF8_CHAR>>;
1054 and if C<flags> is C<UTF8_DISALLOW_ILLEGAL_C9_INTERCHANGE>, this gives
1055 the same results as C<L</isC9_STRICT_UTF8_CHAR>>.
1056 Otherwise C<flags> may be any combination of the C<UTF8_DISALLOW_I<foo>> flags
1057 understood by C<L</utf8n_to_uvchr>>, with the same meanings.
1058 
1059 The three alternative macros are for the most commonly needed validations; they
1060 are likely to run somewhat faster than this more general one, as they can be
1061 inlined into your code.
1062 
1063 Use L</is_utf8_string_flags>, L</is_utf8_string_loc_flags>, and
1064 L</is_utf8_string_loclen_flags> to check entire strings.
1065 
1066 =cut
1067 */
1068 
1069 #define isUTF8_CHAR_flags(s, e, flags)                                      \
1070     (UNLIKELY((e) <= (s))                                                   \
1071     ? 0                                                                     \
1072     : (UTF8_IS_INVARIANT(*s))                                               \
1073       ? 1                                                                   \
1074       : UNLIKELY(((e) - (s)) < UTF8SKIP(s))                                 \
1075         ? 0                                                                 \
1076         : is_utf8_char_helper(s, e, flags))
1077 
1078 /* Do not use; should be deprecated.  Use isUTF8_CHAR() instead; this is
1079  * retained solely for backwards compatibility */
1080 #define IS_UTF8_CHAR(p, n)      (isUTF8_CHAR(p, (p) + (n)) == n)
1081 
1082 #endif /* PERL_UTF8_H_ */
1083 
1084 /*
1085  * ex: set ts=8 sts=4 sw=4 et:
1086  */
1087