1 /* utf8.c
2 *
3 * Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008
4 * by Larry Wall and others
5 *
6 * You may distribute under the terms of either the GNU General Public
7 * License or the Artistic License, as specified in the README file.
8 *
9 */
10
11 /*
12 * 'What a fix!' said Sam. 'That's the one place in all the lands we've ever
13 * heard of that we don't want to see any closer; and that's the one place
14 * we're trying to get to! And that's just where we can't get, nohow.'
15 *
16 * [p.603 of _The Lord of the Rings_, IV/I: "The Taming of Sméagol"]
17 *
18 * 'Well do I understand your speech,' he answered in the same language;
19 * 'yet few strangers do so. Why then do you not speak in the Common Tongue,
20 * as is the custom in the West, if you wish to be answered?'
21 * --Gandalf, addressing Théoden's door wardens
22 *
23 * [p.508 of _The Lord of the Rings_, III/vi: "The King of the Golden Hall"]
24 *
25 * ...the travellers perceived that the floor was paved with stones of many
26 * hues; branching runes and strange devices intertwined beneath their feet.
27 *
28 * [p.512 of _The Lord of the Rings_, III/vi: "The King of the Golden Hall"]
29 */
30
31 #include "EXTERN.h"
32 #define PERL_IN_UTF8_C
33 #include "perl.h"
34 #include "invlist_inline.h"
35
36 static const char malformed_text[] = "Malformed UTF-8 character";
37 static const char unees[] =
38 "Malformed UTF-8 character (unexpected end of string)";
39
40 /*
41 These are various utility functions for manipulating UTF8-encoded
42 strings. For the uninitiated, this is a method of representing arbitrary
43 Unicode characters as a variable number of bytes, in such a way that
44 characters in the ASCII range are unmodified, and a zero byte never appears
45 within non-zero characters.
46 */
47
48 void
Perl__force_out_malformed_utf8_message(pTHX_ const U8 * const p,const U8 * const e,const U32 flags,const bool die_here)49 Perl__force_out_malformed_utf8_message(pTHX_
50 const U8 *const p, /* First byte in UTF-8 sequence */
51 const U8 * const e, /* Final byte in sequence (may include
52 multiple chars */
53 const U32 flags, /* Flags to pass to utf8n_to_uvchr(),
54 usually 0, or some DISALLOW flags */
55 const bool die_here) /* If TRUE, this function does not return */
56 {
57 /* This core-only function is to be called when a malformed UTF-8 character
58 * is found, in order to output the detailed information about the
59 * malformation before dieing. The reason it exists is for the occasions
60 * when such a malformation is fatal, but warnings might be turned off, so
61 * that normally they would not be actually output. This ensures that they
62 * do get output. Because a sequence may be malformed in more than one
63 * way, multiple messages may be generated, so we can't make them fatal, as
64 * that would cause the first one to die.
65 *
66 * Instead we pretend -W was passed to perl, then die afterwards. The
67 * flexibility is here to return to the caller so they can finish up and
68 * die themselves */
69 U32 errors;
70
71 PERL_ARGS_ASSERT__FORCE_OUT_MALFORMED_UTF8_MESSAGE;
72
73 ENTER;
74 SAVEI8(PL_dowarn);
75 SAVESPTR(PL_curcop);
76
77 PL_dowarn = G_WARN_ALL_ON|G_WARN_ON;
78 if (PL_curcop) {
79 SAVECURCOPWARNINGS();
80 PL_curcop->cop_warnings = pWARN_ALL;
81 }
82
83 (void) utf8n_to_uvchr_error(p, e - p, NULL, flags & ~UTF8_CHECK_ONLY, &errors);
84
85 LEAVE;
86
87 if (! errors) {
88 Perl_croak(aTHX_ "panic: _force_out_malformed_utf8_message should"
89 " be called only when there are errors found");
90 }
91
92 if (die_here) {
93 Perl_croak(aTHX_ "Malformed UTF-8 character (fatal)");
94 }
95 }
96
97 STATIC HV *
S_new_msg_hv(pTHX_ const char * const message,U32 categories,U32 flag)98 S_new_msg_hv(pTHX_ const char * const message, /* The message text */
99 U32 categories, /* Packed warning categories */
100 U32 flag) /* Flag associated with this message */
101 {
102 /* Creates, populates, and returns an HV* that describes an error message
103 * for the translators between UTF8 and code point */
104
105 SV* msg_sv = newSVpv(message, 0);
106 SV* category_sv = newSVuv(categories);
107 SV* flag_bit_sv = newSVuv(flag);
108
109 HV* msg_hv = newHV();
110
111 PERL_ARGS_ASSERT_NEW_MSG_HV;
112
113 (void) hv_stores(msg_hv, "text", msg_sv);
114 (void) hv_stores(msg_hv, "warn_categories", category_sv);
115 (void) hv_stores(msg_hv, "flag_bit", flag_bit_sv);
116
117 return msg_hv;
118 }
119
120 /*
121 =for apidoc uvoffuni_to_utf8_flags
122
123 THIS FUNCTION SHOULD BE USED IN ONLY VERY SPECIALIZED CIRCUMSTANCES.
124 Instead, B<Almost all code should use L<perlapi/uvchr_to_utf8> or
125 L<perlapi/uvchr_to_utf8_flags>>.
126
127 This function is like them, but the input is a strict Unicode
128 (as opposed to native) code point. Only in very rare circumstances should code
129 not be using the native code point.
130
131 For details, see the description for L<perlapi/uvchr_to_utf8_flags>.
132
133 =cut
134 */
135
136 U8 *
Perl_uvoffuni_to_utf8_flags(pTHX_ U8 * d,UV uv,const UV flags)137 Perl_uvoffuni_to_utf8_flags(pTHX_ U8 *d, UV uv, const UV flags)
138 {
139 PERL_ARGS_ASSERT_UVOFFUNI_TO_UTF8_FLAGS;
140
141 return uvoffuni_to_utf8_flags_msgs(d, uv, flags, NULL);
142 }
143
144 /* All these formats take a single UV code point argument */
145 const char surrogate_cp_format[] = "UTF-16 surrogate U+%04" UVXf;
146 const char nonchar_cp_format[] = "Unicode non-character U+%04" UVXf
147 " is not recommended for open interchange";
148 const char super_cp_format[] = "Code point 0x%" UVXf " is not Unicode,"
149 " may not be portable";
150
151 /* Use shorter names internally in this file */
152 #define SHIFT UTF_ACCUMULATION_SHIFT
153 #undef MARK
154 #define MARK UTF_CONTINUATION_MARK
155 #define MASK UTF_CONTINUATION_MASK
156
157 /*
158 =for apidoc uvchr_to_utf8_flags_msgs
159
160 THIS FUNCTION SHOULD BE USED IN ONLY VERY SPECIALIZED CIRCUMSTANCES.
161
162 Most code should use C<L</uvchr_to_utf8_flags>()> rather than call this directly.
163
164 This function is for code that wants any warning and/or error messages to be
165 returned to the caller rather than be displayed. All messages that would have
166 been displayed if all lexical warnings are enabled will be returned.
167
168 It is just like C<L</uvchr_to_utf8_flags>> but it takes an extra parameter
169 placed after all the others, C<msgs>. If this parameter is 0, this function
170 behaves identically to C<L</uvchr_to_utf8_flags>>. Otherwise, C<msgs> should
171 be a pointer to an C<HV *> variable, in which this function creates a new HV to
172 contain any appropriate messages. The hash has three key-value pairs, as
173 follows:
174
175 =over 4
176
177 =item C<text>
178
179 The text of the message as a C<SVpv>.
180
181 =item C<warn_categories>
182
183 The warning category (or categories) packed into a C<SVuv>.
184
185 =item C<flag>
186
187 A single flag bit associated with this message, in a C<SVuv>.
188 The bit corresponds to some bit in the C<*errors> return value,
189 such as C<UNICODE_GOT_SURROGATE>.
190
191 =back
192
193 It's important to note that specifying this parameter as non-null will cause
194 any warnings this function would otherwise generate to be suppressed, and
195 instead be placed in C<*msgs>. The caller can check the lexical warnings state
196 (or not) when choosing what to do with the returned messages.
197
198 The caller, of course, is responsible for freeing any returned HV.
199
200 =cut
201 */
202
203 /* Undocumented; we don't want people using this. Instead they should use
204 * uvchr_to_utf8_flags_msgs() */
205 U8 *
Perl_uvoffuni_to_utf8_flags_msgs(pTHX_ U8 * d,UV input_uv,UV flags,HV ** msgs)206 Perl_uvoffuni_to_utf8_flags_msgs(pTHX_ U8 *d, UV input_uv, UV flags, HV** msgs)
207 {
208 U8 *p;
209 UV shifted_uv = input_uv;
210 STRLEN utf8_skip = OFFUNISKIP(input_uv);
211
212 PERL_ARGS_ASSERT_UVOFFUNI_TO_UTF8_FLAGS_MSGS;
213
214 if (msgs) {
215 *msgs = NULL;
216 }
217
218 switch (utf8_skip) {
219 case 1:
220 *d++ = LATIN1_TO_NATIVE(input_uv);
221 return d;
222
223 default:
224 if ( UNLIKELY(input_uv > MAX_LEGAL_CP
225 && UNLIKELY(! (flags & UNICODE_ALLOW_ABOVE_IV_MAX))))
226 {
227 Perl_croak(aTHX_ "%s", form_cp_too_large_msg(16, /* Hex output */
228 NULL, 0, input_uv));
229 }
230
231 if ((flags & (UNICODE_WARN_PERL_EXTENDED|UNICODE_WARN_SUPER))) {
232 U32 category = packWARN2(WARN_NON_UNICODE, WARN_PORTABLE);
233 const char * format = PL_extended_cp_format;
234 if (msgs) {
235 *msgs = new_msg_hv(Perl_form(aTHX_ format, input_uv),
236 category,
237 UNICODE_GOT_PERL_EXTENDED);
238 }
239 else {
240 Perl_ck_warner_d(aTHX_ category, format, input_uv);
241 }
242
243 /* Don't output a 2nd msg */
244 flags &= ~UNICODE_WARN_SUPER;
245 }
246
247 if (flags & UNICODE_DISALLOW_PERL_EXTENDED) {
248 return NULL;
249 }
250
251 p = d + utf8_skip - 1;
252 while (p >= d + 6 + ONE_IF_EBCDIC_ZERO_IF_NOT) {
253 *p-- = I8_TO_NATIVE_UTF8((shifted_uv & MASK) | MARK);
254 shifted_uv >>= SHIFT;
255 }
256
257 /* FALLTHROUGH */
258
259 case 6 + ONE_IF_EBCDIC_ZERO_IF_NOT:
260 d[5 + ONE_IF_EBCDIC_ZERO_IF_NOT]
261 = I8_TO_NATIVE_UTF8((shifted_uv & MASK) | MARK);
262 shifted_uv >>= SHIFT;
263 /* FALLTHROUGH */
264
265 case 5 + ONE_IF_EBCDIC_ZERO_IF_NOT:
266 d[4 + ONE_IF_EBCDIC_ZERO_IF_NOT]
267 = I8_TO_NATIVE_UTF8((shifted_uv & MASK) | MARK);
268 shifted_uv >>= SHIFT;
269 /* FALLTHROUGH */
270
271 case 4 + ONE_IF_EBCDIC_ZERO_IF_NOT:
272 if (UNLIKELY(UNICODE_IS_SUPER(input_uv))) {
273 if (flags & UNICODE_WARN_SUPER) {
274 U32 category = packWARN(WARN_NON_UNICODE);
275 const char * format = super_cp_format;
276
277 if (msgs) {
278 *msgs = new_msg_hv(Perl_form(aTHX_ format, input_uv),
279 category,
280 UNICODE_GOT_SUPER);
281 }
282 else {
283 Perl_ck_warner_d(aTHX_ category, format, input_uv);
284 }
285
286 if (flags & UNICODE_DISALLOW_SUPER) {
287 return NULL;
288 }
289 }
290 if ( (flags & UNICODE_DISALLOW_SUPER)
291 || ( (flags & UNICODE_DISALLOW_PERL_EXTENDED)
292 && UNICODE_IS_PERL_EXTENDED(input_uv)))
293 {
294 return NULL;
295 }
296 }
297
298 d[3 + ONE_IF_EBCDIC_ZERO_IF_NOT]
299 = I8_TO_NATIVE_UTF8((shifted_uv & MASK) | MARK);
300 shifted_uv >>= SHIFT;
301 /* FALLTHROUGH */
302
303 case 3 + ONE_IF_EBCDIC_ZERO_IF_NOT:
304 if (isUNICODE_POSSIBLY_PROBLEMATIC(input_uv)) {
305 if (UNLIKELY(UNICODE_IS_NONCHAR(input_uv))) {
306 if (flags & UNICODE_WARN_NONCHAR) {
307 U32 category = packWARN(WARN_NONCHAR);
308 const char * format = nonchar_cp_format;
309 if (msgs) {
310 *msgs = new_msg_hv(Perl_form(aTHX_ format, input_uv),
311 category,
312 UNICODE_GOT_NONCHAR);
313 }
314 else {
315 Perl_ck_warner_d(aTHX_ category, format, input_uv);
316 }
317 }
318 if (flags & UNICODE_DISALLOW_NONCHAR) {
319 return NULL;
320 }
321 }
322 else if (UNLIKELY(UNICODE_IS_SURROGATE(input_uv))) {
323 if (flags & UNICODE_WARN_SURROGATE) {
324 U32 category = packWARN(WARN_SURROGATE);
325 const char * format = surrogate_cp_format;
326 if (msgs) {
327 *msgs = new_msg_hv(Perl_form(aTHX_ format, input_uv),
328 category,
329 UNICODE_GOT_SURROGATE);
330 }
331 else {
332 Perl_ck_warner_d(aTHX_ category, format, input_uv);
333 }
334 }
335 if (flags & UNICODE_DISALLOW_SURROGATE) {
336 return NULL;
337 }
338 }
339 }
340
341 d[2 + ONE_IF_EBCDIC_ZERO_IF_NOT]
342 = I8_TO_NATIVE_UTF8((shifted_uv & MASK) | MARK);
343 shifted_uv >>= SHIFT;
344 /* FALLTHROUGH */
345
346 #ifdef EBCDIC
347
348 case 3:
349 d[2] = I8_TO_NATIVE_UTF8((shifted_uv & MASK) | MARK);
350 shifted_uv >>= SHIFT;
351 /* FALLTHROUGH */
352
353 #endif
354
355 /* FALLTHROUGH */
356 case 2:
357 d[1] = I8_TO_NATIVE_UTF8((shifted_uv & MASK) | MARK);
358 shifted_uv >>= SHIFT;
359 d[0] = I8_TO_NATIVE_UTF8((shifted_uv & UTF_START_MASK(utf8_skip))
360 | UTF_START_MARK(utf8_skip));
361 break;
362 }
363
364 return d + utf8_skip;
365 }
366
367 /*
368 =for apidoc uvchr_to_utf8
369
370 Adds the UTF-8 representation of the native code point C<uv> to the end
371 of the string C<d>; C<d> should have at least C<UVCHR_SKIP(uv)+1> (up to
372 C<UTF8_MAXBYTES+1>) free bytes available. The return value is the pointer to
373 the byte after the end of the new character. In other words,
374
375 d = uvchr_to_utf8(d, uv);
376
377 is the recommended wide native character-aware way of saying
378
379 *(d++) = uv;
380
381 This function accepts any code point from 0..C<IV_MAX> as input.
382 C<IV_MAX> is typically 0x7FFF_FFFF in a 32-bit word.
383
384 It is possible to forbid or warn on non-Unicode code points, or those that may
385 be problematic by using L</uvchr_to_utf8_flags>.
386
387 =cut
388 */
389
390 /* This is also a macro */
391 PERL_CALLCONV U8* Perl_uvchr_to_utf8(pTHX_ U8 *d, UV uv);
392
393 U8 *
Perl_uvchr_to_utf8(pTHX_ U8 * d,UV uv)394 Perl_uvchr_to_utf8(pTHX_ U8 *d, UV uv)
395 {
396 return uvchr_to_utf8(d, uv);
397 }
398
399 /*
400 =for apidoc uvchr_to_utf8_flags
401
402 Adds the UTF-8 representation of the native code point C<uv> to the end
403 of the string C<d>; C<d> should have at least C<UVCHR_SKIP(uv)+1> (up to
404 C<UTF8_MAXBYTES+1>) free bytes available. The return value is the pointer to
405 the byte after the end of the new character. In other words,
406
407 d = uvchr_to_utf8_flags(d, uv, flags);
408
409 or, in most cases,
410
411 d = uvchr_to_utf8_flags(d, uv, 0);
412
413 This is the Unicode-aware way of saying
414
415 *(d++) = uv;
416
417 If C<flags> is 0, this function accepts any code point from 0..C<IV_MAX> as
418 input. C<IV_MAX> is typically 0x7FFF_FFFF in a 32-bit word.
419
420 Specifying C<flags> can further restrict what is allowed and not warned on, as
421 follows:
422
423 If C<uv> is a Unicode surrogate code point and C<UNICODE_WARN_SURROGATE> is set,
424 the function will raise a warning, provided UTF8 warnings are enabled. If
425 instead C<UNICODE_DISALLOW_SURROGATE> is set, the function will fail and return
426 NULL. If both flags are set, the function will both warn and return NULL.
427
428 Similarly, the C<UNICODE_WARN_NONCHAR> and C<UNICODE_DISALLOW_NONCHAR> flags
429 affect how the function handles a Unicode non-character.
430
431 And likewise, the C<UNICODE_WARN_SUPER> and C<UNICODE_DISALLOW_SUPER> flags
432 affect the handling of code points that are above the Unicode maximum of
433 0x10FFFF. Languages other than Perl may not be able to accept files that
434 contain these.
435
436 The flag C<UNICODE_WARN_ILLEGAL_INTERCHANGE> selects all three of
437 the above WARN flags; and C<UNICODE_DISALLOW_ILLEGAL_INTERCHANGE> selects all
438 three DISALLOW flags. C<UNICODE_DISALLOW_ILLEGAL_INTERCHANGE> restricts the
439 allowed inputs to the strict UTF-8 traditionally defined by Unicode.
440 Similarly, C<UNICODE_WARN_ILLEGAL_C9_INTERCHANGE> and
441 C<UNICODE_DISALLOW_ILLEGAL_C9_INTERCHANGE> are shortcuts to select the
442 above-Unicode and surrogate flags, but not the non-character ones, as
443 defined in
444 L<Unicode Corrigendum #9|https://www.unicode.org/versions/corrigendum9.html>.
445 See L<perlunicode/Noncharacter code points>.
446
447 Extremely high code points were never specified in any standard, and require an
448 extension to UTF-8 to express, which Perl does. It is likely that programs
449 written in something other than Perl would not be able to read files that
450 contain these; nor would Perl understand files written by something that uses a
451 different extension. For these reasons, there is a separate set of flags that
452 can warn and/or disallow these extremely high code points, even if other
453 above-Unicode ones are accepted. They are the C<UNICODE_WARN_PERL_EXTENDED>
454 and C<UNICODE_DISALLOW_PERL_EXTENDED> flags. For more information see
455 C<L</UTF8_GOT_PERL_EXTENDED>>. Of course C<UNICODE_DISALLOW_SUPER> will
456 treat all above-Unicode code points, including these, as malformations. (Note
457 that the Unicode standard considers anything above 0x10FFFF to be illegal, but
458 there are standards predating it that allow up to 0x7FFF_FFFF (2**31 -1))
459
460 A somewhat misleadingly named synonym for C<UNICODE_WARN_PERL_EXTENDED> is
461 retained for backward compatibility: C<UNICODE_WARN_ABOVE_31_BIT>. Similarly,
462 C<UNICODE_DISALLOW_ABOVE_31_BIT> is usable instead of the more accurately named
463 C<UNICODE_DISALLOW_PERL_EXTENDED>. The names are misleading because on EBCDIC
464 platforms,these flags can apply to code points that actually do fit in 31 bits.
465 The new names accurately describe the situation in all cases.
466
467 =for apidoc Amnh||UNICODE_DISALLOW_ABOVE_31_BIT
468 =for apidoc Amnh||UNICODE_DISALLOW_ILLEGAL_C9_INTERCHANGE
469 =for apidoc Amnh||UNICODE_DISALLOW_ILLEGAL_INTERCHANGE
470 =for apidoc Amnh||UNICODE_DISALLOW_NONCHAR
471 =for apidoc Amnh||UNICODE_DISALLOW_PERL_EXTENDED
472 =for apidoc Amnh||UNICODE_DISALLOW_SUPER
473 =for apidoc Amnh||UNICODE_DISALLOW_SURROGATE
474 =for apidoc Amnh||UNICODE_WARN_ABOVE_31_BIT
475 =for apidoc Amnh||UNICODE_WARN_ILLEGAL_C9_INTERCHANGE
476 =for apidoc Amnh||UNICODE_WARN_ILLEGAL_INTERCHANGE
477 =for apidoc Amnh||UNICODE_WARN_NONCHAR
478 =for apidoc Amnh||UNICODE_WARN_PERL_EXTENDED
479 =for apidoc Amnh||UNICODE_WARN_SUPER
480 =for apidoc Amnh||UNICODE_WARN_SURROGATE
481
482 =cut
483 */
484
485 /* This is also a macro */
486 PERL_CALLCONV U8* Perl_uvchr_to_utf8_flags(pTHX_ U8 *d, UV uv, UV flags);
487
488 U8 *
Perl_uvchr_to_utf8_flags(pTHX_ U8 * d,UV uv,UV flags)489 Perl_uvchr_to_utf8_flags(pTHX_ U8 *d, UV uv, UV flags)
490 {
491 return uvchr_to_utf8_flags(d, uv, flags);
492 }
493
494 PERL_STATIC_INLINE int
S_is_utf8_overlong(const U8 * const s,const STRLEN len)495 S_is_utf8_overlong(const U8 * const s, const STRLEN len)
496 {
497 /* Returns an int indicating whether or not the UTF-8 sequence from 's' to
498 * 's' + 'len' - 1 is an overlong. It returns 1 if it is an overlong; 0 if
499 * it isn't, and -1 if there isn't enough information to tell. This last
500 * return value can happen if the sequence is incomplete, missing some
501 * trailing bytes that would form a complete character. If there are
502 * enough bytes to make a definitive decision, this function does so.
503 * Usually 2 bytes are sufficient.
504 *
505 * Overlongs can occur whenever the number of continuation bytes changes.
506 * That means whenever the number of leading 1 bits in a start byte
507 * increases from the next lower start byte. That happens for start bytes
508 * C0, E0, F0, F8, FC, FE, and FF.
509 */
510
511 PERL_ARGS_ASSERT_IS_UTF8_OVERLONG;
512
513 /* Each platform has overlongs after the start bytes given above (expressed
514 * in I8 for EBCDIC). The values below were found by manually inspecting
515 * the UTF-8 patterns. See the tables in utf8.h and utfebcdic.h. */
516
517 switch (NATIVE_UTF8_TO_I8(s[0])) {
518 default:
519 assert(UTF8_IS_START(s[0]));
520 return 0;
521
522 case 0xC0:
523 case 0xC1:
524 return 1;
525
526 #ifdef EBCDIC
527
528 case 0xC2:
529 case 0xC3:
530 case 0xC4:
531 case 0xE0:
532 return 1;
533 #else
534 case 0xE0:
535 return (len < 2) ? -1 : s[1] < 0xA0;
536 #endif
537
538 case 0xF0:
539 return (len < 2)
540 ? -1
541 : NATIVE_UTF8_TO_I8(s[1]) < UTF_MIN_CONTINUATION_BYTE + 0x10;
542 case 0xF8:
543 return (len < 2)
544 ? -1
545 : NATIVE_UTF8_TO_I8(s[1]) < UTF_MIN_CONTINUATION_BYTE + 0x08;
546 case 0xFC:
547 return (len < 2)
548 ? -1
549 : NATIVE_UTF8_TO_I8(s[1]) < UTF_MIN_CONTINUATION_BYTE + 0x04;
550 case 0xFE:
551 return (len < 2)
552 ? -1
553 : NATIVE_UTF8_TO_I8(s[1]) < UTF_MIN_CONTINUATION_BYTE + 0x02;
554 case 0xFF:
555 return isFF_overlong(s, len);
556 }
557 }
558
559 PERL_STATIC_INLINE int
S_isFF_overlong(const U8 * const s,const STRLEN len)560 S_isFF_overlong(const U8 * const s, const STRLEN len)
561 {
562 /* Returns an int indicating whether or not the UTF-8 sequence from 's' to
563 * 'e' - 1 is an overlong beginning with \xFF. It returns 1 if it is; 0 if
564 * it isn't, and -1 if there isn't enough information to tell. This last
565 * return value can happen if the sequence is incomplete, missing some
566 * trailing bytes that would form a complete character. If there are
567 * enough bytes to make a definitive decision, this function does so. */
568
569 PERL_ARGS_ASSERT_ISFF_OVERLONG;
570
571 #ifdef EBCDIC
572 /* This works on all three EBCDIC code pages traditionally supported by
573 * perl */
574 # define FF_OVERLONG_PREFIX "\xfe\x41\x41\x41\x41\x41\x41\x41"
575 #else
576 # define FF_OVERLONG_PREFIX "\xff\x80\x80\x80\x80\x80\x80"
577 #endif
578
579 /* To be an FF overlong, all the available bytes must match */
580 if (LIKELY(memNE(s, FF_OVERLONG_PREFIX,
581 MIN(len, STRLENs(FF_OVERLONG_PREFIX)))))
582 {
583 return 0;
584 }
585
586 /* To be an FF overlong sequence, all the bytes in FF_OVERLONG_PREFIX must
587 * be there; what comes after them doesn't matter. See tables in utf8.h,
588 * utfebcdic.h. */
589 if (len >= STRLENs(FF_OVERLONG_PREFIX)) {
590 return 1;
591 }
592
593 /* The missing bytes could cause the result to go one way or the other, so
594 * the result is indeterminate */
595 return -1;
596 }
597
598 /* At some point we may want to allow core to use up to UV_MAX */
599
600 #ifdef EBCDIC /* Actually is I8 */
601 # if defined(UV_IS_QUAD) /* These assume IV_MAX is 2**63-1, UV_MAX 2**64-1 */
602 # define HIGHEST_REPRESENTABLE_UTF "\xFF\xA7"
603 /* UV_MAX "\xFF\xAF" */
604 # else /* These assume IV_MAX is 2**31-1, UV_MAX 2**32-1 */
605 # define HIGHEST_REPRESENTABLE_UTF "\xFF\xA0\xA0\xA0\xA0\xA0\xA0\xA1"
606 /* UV_MAX "\xFF\xA0\xA0\xA0\xA0\xA0\xA0\xA3" */
607 # endif
608 #else
609 # if defined(UV_IS_QUAD)
610 # define HIGHEST_REPRESENTABLE_UTF "\xFF\x80\x87"
611 /* UV_MAX "\xFF\x80" */
612 # else
613 # define HIGHEST_REPRESENTABLE_UTF "\xFD"
614 /* UV_MAX "\xFE\x83" */
615 # endif
616 #endif
617
618 PERL_STATIC_INLINE int
S_does_utf8_overflow(const U8 * const s,const U8 * e,const bool consider_overlongs)619 S_does_utf8_overflow(const U8 * const s,
620 const U8 * e,
621 const bool consider_overlongs)
622 {
623 /* Returns an int indicating whether or not the UTF-8 sequence from 's' to
624 * 'e' - 1 would overflow an IV on this platform; that is if it represents
625 * a code point larger than the highest representable code point. It
626 * returns 1 if it does overflow; 0 if it doesn't, and -1 if there isn't
627 * enough information to tell. This last return value can happen if the
628 * sequence is incomplete, missing some trailing bytes that would form a
629 * complete character. If there are enough bytes to make a definitive
630 * decision, this function does so.
631 *
632 * If 'consider_overlongs' is TRUE, the function checks for the possibility
633 * that the sequence is an overlong that doesn't overflow. Otherwise, it
634 * assumes the sequence is not an overlong. This can give different
635 * results only on ASCII 32-bit platforms.
636 *
637 * (For ASCII platforms, we could use memcmp() because we don't have to
638 * convert each byte to I8, but it's very rare input indeed that would
639 * approach overflow, so the loop below will likely only get executed once.)
640 *
641 */
642 const STRLEN len = e - s;
643 const U8 *x;
644 const U8 * y = (const U8 *) HIGHEST_REPRESENTABLE_UTF;
645 int is_overlong = 0;
646
647 PERL_ARGS_ASSERT_DOES_UTF8_OVERFLOW;
648
649 for (x = s; x < e; x++, y++) {
650
651 /* 'y' is set up to not include the trailing bytes that are all the
652 * maximum possible continuation byte. So when we reach the end of 'y'
653 * (known to be NUL terminated), it is impossible for 'x' to contain
654 * bytes larger than those omitted bytes, and therefore 'x' can't
655 * overflow */
656 if (*y == '\0') {
657 return 0;
658 }
659
660 /* If this byte is less than the corresponding highest non-overflowing
661 * UTF-8, the sequence doesn't overflow */
662 if (NATIVE_UTF8_TO_I8(*x) < *y) {
663 return 0;
664 }
665
666 if (UNLIKELY(NATIVE_UTF8_TO_I8(*x) > *y)) {
667 goto overflows_if_not_overlong;
668 }
669 }
670
671 /* Got to the end, and all bytes are the same. If the input is a whole
672 * character, it doesn't overflow. And if it is a partial character,
673 * there's not enough information to tell */
674 return (len >= STRLENs(HIGHEST_REPRESENTABLE_UTF)) ? 0 : -1;
675
676 overflows_if_not_overlong:
677
678 /* Here, a well-formed sequence overflows. If we are assuming
679 * well-formedness, return that it overflows. */
680 if (! consider_overlongs) {
681 return 1;
682 }
683
684 /* Here, it could be the overlong malformation, and might not actually
685 * overflow if you were to calculate it out.
686 *
687 * See if it actually is overlong */
688 is_overlong = is_utf8_overlong(s, len);
689
690 /* If it isn't overlong, is well-formed, so overflows */
691 if (is_overlong == 0) {
692 return 1;
693 }
694
695 /* Not long enough to determine */
696 if (is_overlong < 0) {
697 return -1;
698 }
699
700 /* Here, it appears to overflow, but it is also overlong */
701
702 #if 6 * UTF_CONTINUATION_BYTE_INFO_BITS <= IVSIZE * CHARBITS
703
704 /* On many platforms, it is impossible for an overlong to overflow. For
705 * these, no further work is necessary: we can return immediately that this
706 * overlong that is an apparent overflow actually isn't
707 *
708 * To see why, note that a length_N sequence can represent as overlongs all
709 * the code points representable by shorter length sequences, but no
710 * higher. If it could represent a higher code point without being an
711 * overlong, we wouldn't have had to increase the sequence length!
712 *
713 * The highest possible start byte is FF; the next highest is FE. The
714 * highest code point representable as an overlong on the platform is thus
715 * the highest code point representable by a non-overlong sequence whose
716 * start byte is FE. If that value doesn't overflow the platform's word
717 * size, overlongs can't overflow.
718 *
719 * FE consists of 7 bytes total; the FE start byte contributes 0 bits of
720 * information (the high 7 bits, all ones, say that the sequence is 7 bytes
721 * long, and the bottom, zero, bit is s placeholder. That leaves the 6
722 * continuation bytes to contribute UTF_CONTINUATION_BYTE_INFO_BITS each.
723 If that number of bits doesn't exceed the word size, it can't overflow. */
724
725 return 0;
726
727 #else
728
729 /* In practice, only a 32-bit ASCII box gets here. The FE start byte can
730 * represent, as an overlong, the highest code point representable by an FD
731 * start byte, which is 5*6 continuation bytes of info plus one bit from
732 * the start byte, or 31 bits. That doesn't overflow. More explicitly:
733 * \xFD\xBF\xBF\xBF\xBF\xBF evaluates to 0x7FFFFFFF = 2*31 - 1.
734 *
735 * That means only the FF start byte can have an overflowing overlong. */
736 if (*s < 0xFF) {
737 return 0;
738 }
739
740 /* The sequence \xff\x80\x80\x80\x80\x80\x80\x82 is an overlong that
741 * evaluates to 2**31, so overflows an IV. For a UV it's
742 * \xff\x80\x80\x80\x80\x80\x80\x83 = 2**32 */
743 # define OVERFLOWS "\xff\x80\x80\x80\x80\x80\x80\x82"
744
745 if (e - s < (Ptrdiff_t) STRLENs(OVERFLOWS)) { /* Not enough info */
746 return -1;
747 }
748
749 # define strnGE(s1,s2,l) (strncmp(s1,s2,l) >= 0)
750
751 return strnGE((const char *) s, OVERFLOWS, STRLENs(OVERFLOWS));
752
753 #endif
754
755 }
756
757 STRLEN
Perl_is_utf8_char_helper_(const U8 * const s,const U8 * e,const U32 flags)758 Perl_is_utf8_char_helper_(const U8 * const s, const U8 * e, const U32 flags)
759 {
760 SSize_t len, full_len;
761
762 /* An internal helper function.
763 *
764 * On input:
765 * 's' is a string, which is known to be syntactically valid UTF-8 as far
766 * as (e - 1); e > s must hold.
767 * 'e' This function is allowed to look at any byte from 's'...'e-1', but
768 * nowhere else. The function has to cope as best it can if that
769 * sequence does not form a full character.
770 * 'flags' can be 0, or any combination of the UTF8_DISALLOW_foo flags
771 * accepted by L</utf8n_to_uvchr>. If non-zero, this function returns
772 * 0 if it determines the input will match something disallowed.
773 * On output:
774 * The return is the number of bytes required to represent the code point
775 * if it isn't disallowed by 'flags'; 0 otherwise. Be aware that if the
776 * input is for a partial character, a successful return will be larger
777 * than 'e - s'.
778 *
779 * If *s..*(e-1) is only for a partial character, the function will return
780 * non-zero if there is any sequence of well-formed UTF-8 that, when
781 * appended to the input sequence, could result in an allowed code point;
782 * otherwise it returns 0. Non characters cannot be determined based on
783 * partial character input. But many of the other excluded types can be
784 * determined with just the first one or two bytes.
785 *
786 */
787
788 PERL_ARGS_ASSERT_IS_UTF8_CHAR_HELPER_;
789
790 assert(e > s);
791 assert(0 == (flags & ~(UTF8_DISALLOW_ILLEGAL_INTERCHANGE
792 |UTF8_DISALLOW_PERL_EXTENDED)));
793
794 full_len = UTF8SKIP(s);
795
796 len = e - s;
797 if (len > full_len) {
798 e = s + full_len;
799 len = full_len;
800 }
801
802 switch (full_len) {
803 bool is_super;
804
805 default: /* Extended */
806 if (flags & UTF8_DISALLOW_PERL_EXTENDED) {
807 return 0;
808 }
809
810 /* FALLTHROUGH */
811
812 case 6 + ONE_IF_EBCDIC_ZERO_IF_NOT: /* above Unicode */
813 case 5 + ONE_IF_EBCDIC_ZERO_IF_NOT: /* above Unicode */
814
815 if (flags & UTF8_DISALLOW_SUPER) {
816 return 0; /* Above Unicode */
817 }
818
819 return full_len;
820
821 case 4 + ONE_IF_EBCDIC_ZERO_IF_NOT:
822 is_super = ( UNLIKELY(NATIVE_UTF8_TO_I8(s[0]) > UTF_START_BYTE_110000_)
823 || ( len > 1
824 && NATIVE_UTF8_TO_I8(s[0]) == UTF_START_BYTE_110000_
825 && NATIVE_UTF8_TO_I8(s[1])
826 >= UTF_FIRST_CONT_BYTE_110000_));
827 if (is_super) {
828 if (flags & UTF8_DISALLOW_SUPER) {
829 return 0;
830 }
831 }
832 else if ( (flags & UTF8_DISALLOW_NONCHAR)
833 && len == full_len
834 && UNLIKELY(is_LARGER_NON_CHARS_utf8(s)))
835 {
836 return 0;
837 }
838
839 return full_len;
840
841 case 3 + ONE_IF_EBCDIC_ZERO_IF_NOT:
842
843 if (! isUTF8_POSSIBLY_PROBLEMATIC(s[0]) || len < 2) {
844 return full_len;
845 }
846
847 if ( (flags & UTF8_DISALLOW_SURROGATE)
848 && UNLIKELY(is_SURROGATE_utf8(s)))
849 {
850 return 0; /* Surrogate */
851 }
852
853 if ( (flags & UTF8_DISALLOW_NONCHAR)
854 && len == full_len
855 && UNLIKELY(is_SHORTER_NON_CHARS_utf8(s)))
856 {
857 return 0;
858 }
859
860 return full_len;
861
862 /* The lower code points don't have any disallowable characters */
863 #ifdef EBCDIC
864 case 3:
865 return full_len;
866 #endif
867
868 case 2:
869 case 1:
870 return full_len;
871 }
872 }
873
874 Size_t
Perl_is_utf8_FF_helper_(const U8 * const s0,const U8 * const e,const bool require_partial)875 Perl_is_utf8_FF_helper_(const U8 * const s0, const U8 * const e,
876 const bool require_partial)
877 {
878 /* This is called to determine if the UTF-8 sequence starting at s0 and
879 * continuing for up to one full character of bytes, but looking no further
880 * than 'e - 1', is legal. *s0 must be 0xFF (or whatever the native
881 * equivalent of FF in I8 on EBCDIC platforms is). This marks it as being
882 * for the largest code points recognized by Perl, the ones that require
883 * the most UTF-8 bytes per character to represent (somewhat less than
884 * twice the size of the next longest kind). This sequence will only ever
885 * be Perl extended UTF-8.
886 *
887 * The routine returns 0 if the sequence is not fully valid, syntactically
888 * or semantically. That means it checks that everything following the
889 * start byte is a continuation byte, and that it doesn't overflow, nor is
890 * an overlong representation.
891 *
892 * If 'require_partial' is FALSE, the routine returns non-zero only if the
893 * input (as far as 'e-1') is a full character. The return is the count of
894 * the bytes in the character.
895 *
896 * If 'require_partial' is TRUE, the routine returns non-zero only if the
897 * input as far as 'e-1' is a partial, not full character, with no
898 * malformations found before position 'e'. The return is either just
899 * FALSE, or TRUE. */
900
901 const U8 *s = s0 + 1;
902 const U8 *send = e;
903
904 PERL_ARGS_ASSERT_IS_UTF8_FF_HELPER_;
905
906 assert(s0 < e);
907 assert(*s0 == I8_TO_NATIVE_UTF8(0xFF));
908
909 send = s + MIN(UTF8_MAXBYTES - 1, e - s);
910 while (s < send) {
911 if (! UTF8_IS_CONTINUATION(*s)) {
912 return 0;
913 }
914
915 s++;
916 }
917
918 if (0 < does_utf8_overflow(s0, e,
919 FALSE /* Don't consider_overlongs */
920 )) {
921 return 0;
922 }
923
924 if (0 < isFF_overlong(s0, e - s0)) {
925 return 0;
926 }
927
928 /* Here, the character is valid as far as it got. Check if got a partial
929 * character */
930 if (s - s0 < UTF8_MAXBYTES) {
931 return (require_partial) ? 1 : 0;
932 }
933
934 /* Here, got a full character */
935 return (require_partial) ? 0 : UTF8_MAXBYTES;
936 }
937
938 char *
Perl__byte_dump_string(pTHX_ const U8 * const start,const STRLEN len,const bool format)939 Perl__byte_dump_string(pTHX_ const U8 * const start, const STRLEN len, const bool format)
940 {
941 /* Returns a mortalized C string that is a displayable copy of the 'len'
942 * bytes starting at 'start'. 'format' gives how to display each byte.
943 * Currently, there are only two formats, so it is currently a bool:
944 * 0 \xab
945 * 1 ab (that is a space between two hex digit bytes)
946 */
947
948 const STRLEN output_len = 4 * len + 1; /* 4 bytes per each input, plus a
949 trailing NUL */
950 const U8 * s = start;
951 const U8 * const e = start + len;
952 char * output;
953 char * d;
954
955 PERL_ARGS_ASSERT__BYTE_DUMP_STRING;
956
957 Newx(output, output_len, char);
958 SAVEFREEPV(output);
959
960 d = output;
961 for (s = start; s < e; s++) {
962 const unsigned high_nibble = (*s & 0xF0) >> 4;
963 const unsigned low_nibble = (*s & 0x0F);
964
965 if (format) {
966 if (s > start) {
967 *d++ = ' ';
968 }
969 }
970 else {
971 *d++ = '\\';
972 *d++ = 'x';
973 }
974
975 if (high_nibble < 10) {
976 *d++ = high_nibble + '0';
977 }
978 else {
979 *d++ = high_nibble - 10 + 'a';
980 }
981
982 if (low_nibble < 10) {
983 *d++ = low_nibble + '0';
984 }
985 else {
986 *d++ = low_nibble - 10 + 'a';
987 }
988 }
989
990 *d = '\0';
991 return output;
992 }
993
994 PERL_STATIC_INLINE char *
S_unexpected_non_continuation_text(pTHX_ const U8 * const s,STRLEN print_len,const STRLEN non_cont_byte_pos,const STRLEN expect_len)995 S_unexpected_non_continuation_text(pTHX_ const U8 * const s,
996
997 /* Max number of bytes to print */
998 STRLEN print_len,
999
1000 /* Which one is the non-continuation */
1001 const STRLEN non_cont_byte_pos,
1002
1003 /* How many bytes should there be? */
1004 const STRLEN expect_len)
1005 {
1006 /* Return the malformation warning text for an unexpected continuation
1007 * byte. */
1008
1009 const char * const where = (non_cont_byte_pos == 1)
1010 ? "immediately"
1011 : Perl_form(aTHX_ "%d bytes",
1012 (int) non_cont_byte_pos);
1013 const U8 * x = s + non_cont_byte_pos;
1014 const U8 * e = s + print_len;
1015
1016 PERL_ARGS_ASSERT_UNEXPECTED_NON_CONTINUATION_TEXT;
1017
1018 /* We don't need to pass this parameter, but since it has already been
1019 * calculated, it's likely faster to pass it; verify under DEBUGGING */
1020 assert(expect_len == UTF8SKIP(s));
1021
1022 /* As a defensive coding measure, don't output anything past a NUL. Such
1023 * bytes shouldn't be in the middle of a malformation, and could mark the
1024 * end of the allocated string, and what comes after is undefined */
1025 for (; x < e; x++) {
1026 if (*x == '\0') {
1027 x++; /* Output this particular NUL */
1028 break;
1029 }
1030 }
1031
1032 return Perl_form(aTHX_ "%s: %s (unexpected non-continuation byte 0x%02x,"
1033 " %s after start byte 0x%02x; need %d bytes, got %d)",
1034 malformed_text,
1035 _byte_dump_string(s, x - s, 0),
1036 *(s + non_cont_byte_pos),
1037 where,
1038 *s,
1039 (int) expect_len,
1040 (int) non_cont_byte_pos);
1041 }
1042
1043 /*
1044
1045 =for apidoc utf8n_to_uvchr
1046
1047 THIS FUNCTION SHOULD BE USED IN ONLY VERY SPECIALIZED CIRCUMSTANCES.
1048 Most code should use L</utf8_to_uvchr_buf>() rather than call this
1049 directly.
1050
1051 Bottom level UTF-8 decode routine.
1052 Returns the native code point value of the first character in the string C<s>,
1053 which is assumed to be in UTF-8 (or UTF-EBCDIC) encoding, and no longer than
1054 C<curlen> bytes; C<*retlen> (if C<retlen> isn't NULL) will be set to
1055 the length, in bytes, of that character.
1056
1057 The value of C<flags> determines the behavior when C<s> does not point to a
1058 well-formed UTF-8 character. If C<flags> is 0, encountering a malformation
1059 causes zero to be returned and C<*retlen> is set so that (S<C<s> + C<*retlen>>)
1060 is the next possible position in C<s> that could begin a non-malformed
1061 character. Also, if UTF-8 warnings haven't been lexically disabled, a warning
1062 is raised. Some UTF-8 input sequences may contain multiple malformations.
1063 This function tries to find every possible one in each call, so multiple
1064 warnings can be raised for the same sequence.
1065
1066 Various ALLOW flags can be set in C<flags> to allow (and not warn on)
1067 individual types of malformations, such as the sequence being overlong (that
1068 is, when there is a shorter sequence that can express the same code point;
1069 overlong sequences are expressly forbidden in the UTF-8 standard due to
1070 potential security issues). Another malformation example is the first byte of
1071 a character not being a legal first byte. See F<utf8.h> for the list of such
1072 flags. Even if allowed, this function generally returns the Unicode
1073 REPLACEMENT CHARACTER when it encounters a malformation. There are flags in
1074 F<utf8.h> to override this behavior for the overlong malformations, but don't
1075 do that except for very specialized purposes.
1076
1077 The C<UTF8_CHECK_ONLY> flag overrides the behavior when a non-allowed (by other
1078 flags) malformation is found. If this flag is set, the routine assumes that
1079 the caller will raise a warning, and this function will silently just set
1080 C<retlen> to C<-1> (cast to C<STRLEN>) and return zero.
1081
1082 Note that this API requires disambiguation between successful decoding a C<NUL>
1083 character, and an error return (unless the C<UTF8_CHECK_ONLY> flag is set), as
1084 in both cases, 0 is returned, and, depending on the malformation, C<retlen> may
1085 be set to 1. To disambiguate, upon a zero return, see if the first byte of
1086 C<s> is 0 as well. If so, the input was a C<NUL>; if not, the input had an
1087 error. Or you can use C<L</utf8n_to_uvchr_error>>.
1088
1089 Certain code points are considered problematic. These are Unicode surrogates,
1090 Unicode non-characters, and code points above the Unicode maximum of 0x10FFFF.
1091 By default these are considered regular code points, but certain situations
1092 warrant special handling for them, which can be specified using the C<flags>
1093 parameter. If C<flags> contains C<UTF8_DISALLOW_ILLEGAL_INTERCHANGE>, all
1094 three classes are treated as malformations and handled as such. The flags
1095 C<UTF8_DISALLOW_SURROGATE>, C<UTF8_DISALLOW_NONCHAR>, and
1096 C<UTF8_DISALLOW_SUPER> (meaning above the legal Unicode maximum) can be set to
1097 disallow these categories individually. C<UTF8_DISALLOW_ILLEGAL_INTERCHANGE>
1098 restricts the allowed inputs to the strict UTF-8 traditionally defined by
1099 Unicode. Use C<UTF8_DISALLOW_ILLEGAL_C9_INTERCHANGE> to use the strictness
1100 definition given by
1101 L<Unicode Corrigendum #9|https://www.unicode.org/versions/corrigendum9.html>.
1102 The difference between traditional strictness and C9 strictness is that the
1103 latter does not forbid non-character code points. (They are still discouraged,
1104 however.) For more discussion see L<perlunicode/Noncharacter code points>.
1105
1106 The flags C<UTF8_WARN_ILLEGAL_INTERCHANGE>,
1107 C<UTF8_WARN_ILLEGAL_C9_INTERCHANGE>, C<UTF8_WARN_SURROGATE>,
1108 C<UTF8_WARN_NONCHAR>, and C<UTF8_WARN_SUPER> will cause warning messages to be
1109 raised for their respective categories, but otherwise the code points are
1110 considered valid (not malformations). To get a category to both be treated as
1111 a malformation and raise a warning, specify both the WARN and DISALLOW flags.
1112 (But note that warnings are not raised if lexically disabled nor if
1113 C<UTF8_CHECK_ONLY> is also specified.)
1114
1115 Extremely high code points were never specified in any standard, and require an
1116 extension to UTF-8 to express, which Perl does. It is likely that programs
1117 written in something other than Perl would not be able to read files that
1118 contain these; nor would Perl understand files written by something that uses a
1119 different extension. For these reasons, there is a separate set of flags that
1120 can warn and/or disallow these extremely high code points, even if other
1121 above-Unicode ones are accepted. They are the C<UTF8_WARN_PERL_EXTENDED> and
1122 C<UTF8_DISALLOW_PERL_EXTENDED> flags. For more information see
1123 C<L</UTF8_GOT_PERL_EXTENDED>>. Of course C<UTF8_DISALLOW_SUPER> will treat all
1124 above-Unicode code points, including these, as malformations.
1125 (Note that the Unicode standard considers anything above 0x10FFFF to be
1126 illegal, but there are standards predating it that allow up to 0x7FFF_FFFF
1127 (2**31 -1))
1128
1129 A somewhat misleadingly named synonym for C<UTF8_WARN_PERL_EXTENDED> is
1130 retained for backward compatibility: C<UTF8_WARN_ABOVE_31_BIT>. Similarly,
1131 C<UTF8_DISALLOW_ABOVE_31_BIT> is usable instead of the more accurately named
1132 C<UTF8_DISALLOW_PERL_EXTENDED>. The names are misleading because these flags
1133 can apply to code points that actually do fit in 31 bits. This happens on
1134 EBCDIC platforms, and sometimes when the L<overlong
1135 malformation|/C<UTF8_GOT_LONG>> is also present. The new names accurately
1136 describe the situation in all cases.
1137
1138
1139 All other code points corresponding to Unicode characters, including private
1140 use and those yet to be assigned, are never considered malformed and never
1141 warn.
1142
1143 =for apidoc Amnh||UTF8_CHECK_ONLY
1144 =for apidoc Amnh||UTF8_DISALLOW_ILLEGAL_INTERCHANGE
1145 =for apidoc Amnh||UTF8_DISALLOW_ILLEGAL_C9_INTERCHANGE
1146 =for apidoc Amnh||UTF8_DISALLOW_SURROGATE
1147 =for apidoc Amnh||UTF8_DISALLOW_NONCHAR
1148 =for apidoc Amnh||UTF8_DISALLOW_SUPER
1149 =for apidoc Amnh||UTF8_WARN_ILLEGAL_INTERCHANGE
1150 =for apidoc Amnh||UTF8_WARN_ILLEGAL_C9_INTERCHANGE
1151 =for apidoc Amnh||UTF8_WARN_SURROGATE
1152 =for apidoc Amnh||UTF8_WARN_NONCHAR
1153 =for apidoc Amnh||UTF8_WARN_SUPER
1154 =for apidoc Amnh||UTF8_WARN_PERL_EXTENDED
1155 =for apidoc Amnh||UTF8_DISALLOW_PERL_EXTENDED
1156
1157 =cut
1158
1159 Also implemented as a macro in utf8.h
1160 */
1161
1162 UV
Perl_utf8n_to_uvchr(const U8 * s,STRLEN curlen,STRLEN * retlen,const U32 flags)1163 Perl_utf8n_to_uvchr(const U8 *s,
1164 STRLEN curlen,
1165 STRLEN *retlen,
1166 const U32 flags)
1167 {
1168 PERL_ARGS_ASSERT_UTF8N_TO_UVCHR;
1169
1170 return utf8n_to_uvchr_error(s, curlen, retlen, flags, NULL);
1171 }
1172
1173 /*
1174
1175 =for apidoc utf8n_to_uvchr_error
1176
1177 THIS FUNCTION SHOULD BE USED IN ONLY VERY SPECIALIZED CIRCUMSTANCES.
1178 Most code should use L</utf8_to_uvchr_buf>() rather than call this
1179 directly.
1180
1181 This function is for code that needs to know what the precise malformation(s)
1182 are when an error is found. If you also need to know the generated warning
1183 messages, use L</utf8n_to_uvchr_msgs>() instead.
1184
1185 It is like C<L</utf8n_to_uvchr>> but it takes an extra parameter placed after
1186 all the others, C<errors>. If this parameter is 0, this function behaves
1187 identically to C<L</utf8n_to_uvchr>>. Otherwise, C<errors> should be a pointer
1188 to a C<U32> variable, which this function sets to indicate any errors found.
1189 Upon return, if C<*errors> is 0, there were no errors found. Otherwise,
1190 C<*errors> is the bit-wise C<OR> of the bits described in the list below. Some
1191 of these bits will be set if a malformation is found, even if the input
1192 C<flags> parameter indicates that the given malformation is allowed; those
1193 exceptions are noted:
1194
1195 =over 4
1196
1197 =item C<UTF8_GOT_PERL_EXTENDED>
1198
1199 The input sequence is not standard UTF-8, but a Perl extension. This bit is
1200 set only if the input C<flags> parameter contains either the
1201 C<UTF8_DISALLOW_PERL_EXTENDED> or the C<UTF8_WARN_PERL_EXTENDED> flags.
1202
1203 Code points above 0x7FFF_FFFF (2**31 - 1) were never specified in any standard,
1204 and so some extension must be used to express them. Perl uses a natural
1205 extension to UTF-8 to represent the ones up to 2**36-1, and invented a further
1206 extension to represent even higher ones, so that any code point that fits in a
1207 64-bit word can be represented. Text using these extensions is not likely to
1208 be portable to non-Perl code. We lump both of these extensions together and
1209 refer to them as Perl extended UTF-8. There exist other extensions that people
1210 have invented, incompatible with Perl's.
1211
1212 On EBCDIC platforms starting in Perl v5.24, the Perl extension for representing
1213 extremely high code points kicks in at 0x3FFF_FFFF (2**30 -1), which is lower
1214 than on ASCII. Prior to that, code points 2**31 and higher were simply
1215 unrepresentable, and a different, incompatible method was used to represent
1216 code points between 2**30 and 2**31 - 1.
1217
1218 On both platforms, ASCII and EBCDIC, C<UTF8_GOT_PERL_EXTENDED> is set if
1219 Perl extended UTF-8 is used.
1220
1221 In earlier Perls, this bit was named C<UTF8_GOT_ABOVE_31_BIT>, which you still
1222 may use for backward compatibility. That name is misleading, as this flag may
1223 be set when the code point actually does fit in 31 bits. This happens on
1224 EBCDIC platforms, and sometimes when the L<overlong
1225 malformation|/C<UTF8_GOT_LONG>> is also present. The new name accurately
1226 describes the situation in all cases.
1227
1228 =item C<UTF8_GOT_CONTINUATION>
1229
1230 The input sequence was malformed in that the first byte was a UTF-8
1231 continuation byte.
1232
1233 =item C<UTF8_GOT_EMPTY>
1234
1235 The input C<curlen> parameter was 0.
1236
1237 =item C<UTF8_GOT_LONG>
1238
1239 The input sequence was malformed in that there is some other sequence that
1240 evaluates to the same code point, but that sequence is shorter than this one.
1241
1242 Until Unicode 3.1, it was legal for programs to accept this malformation, but
1243 it was discovered that this created security issues.
1244
1245 =item C<UTF8_GOT_NONCHAR>
1246
1247 The code point represented by the input UTF-8 sequence is for a Unicode
1248 non-character code point.
1249 This bit is set only if the input C<flags> parameter contains either the
1250 C<UTF8_DISALLOW_NONCHAR> or the C<UTF8_WARN_NONCHAR> flags.
1251
1252 =item C<UTF8_GOT_NON_CONTINUATION>
1253
1254 The input sequence was malformed in that a non-continuation type byte was found
1255 in a position where only a continuation type one should be. See also
1256 C<L</UTF8_GOT_SHORT>>.
1257
1258 =item C<UTF8_GOT_OVERFLOW>
1259
1260 The input sequence was malformed in that it is for a code point that is not
1261 representable in the number of bits available in an IV on the current platform.
1262
1263 =item C<UTF8_GOT_SHORT>
1264
1265 The input sequence was malformed in that C<curlen> is smaller than required for
1266 a complete sequence. In other words, the input is for a partial character
1267 sequence.
1268
1269
1270 C<UTF8_GOT_SHORT> and C<UTF8_GOT_NON_CONTINUATION> both indicate a too short
1271 sequence. The difference is that C<UTF8_GOT_NON_CONTINUATION> indicates always
1272 that there is an error, while C<UTF8_GOT_SHORT> means that an incomplete
1273 sequence was looked at. If no other flags are present, it means that the
1274 sequence was valid as far as it went. Depending on the application, this could
1275 mean one of three things:
1276
1277 =over
1278
1279 =item *
1280
1281 The C<curlen> length parameter passed in was too small, and the function was
1282 prevented from examining all the necessary bytes.
1283
1284 =item *
1285
1286 The buffer being looked at is based on reading data, and the data received so
1287 far stopped in the middle of a character, so that the next read will
1288 read the remainder of this character. (It is up to the caller to deal with the
1289 split bytes somehow.)
1290
1291 =item *
1292
1293 This is a real error, and the partial sequence is all we're going to get.
1294
1295 =back
1296
1297 =item C<UTF8_GOT_SUPER>
1298
1299 The input sequence was malformed in that it is for a non-Unicode code point;
1300 that is, one above the legal Unicode maximum.
1301 This bit is set only if the input C<flags> parameter contains either the
1302 C<UTF8_DISALLOW_SUPER> or the C<UTF8_WARN_SUPER> flags.
1303
1304 =item C<UTF8_GOT_SURROGATE>
1305
1306 The input sequence was malformed in that it is for a -Unicode UTF-16 surrogate
1307 code point.
1308 This bit is set only if the input C<flags> parameter contains either the
1309 C<UTF8_DISALLOW_SURROGATE> or the C<UTF8_WARN_SURROGATE> flags.
1310
1311 =back
1312
1313 To do your own error handling, call this function with the C<UTF8_CHECK_ONLY>
1314 flag to suppress any warnings, and then examine the C<*errors> return.
1315
1316 =for apidoc Amnh||UTF8_GOT_PERL_EXTENDED
1317 =for apidoc Amnh||UTF8_GOT_CONTINUATION
1318 =for apidoc Amnh||UTF8_GOT_EMPTY
1319 =for apidoc Amnh||UTF8_GOT_LONG
1320 =for apidoc Amnh||UTF8_GOT_NONCHAR
1321 =for apidoc Amnh||UTF8_GOT_NON_CONTINUATION
1322 =for apidoc Amnh||UTF8_GOT_OVERFLOW
1323 =for apidoc Amnh||UTF8_GOT_SHORT
1324 =for apidoc Amnh||UTF8_GOT_SUPER
1325 =for apidoc Amnh||UTF8_GOT_SURROGATE
1326
1327 =cut
1328
1329 Also implemented as a macro in utf8.h
1330 */
1331
1332 UV
Perl_utf8n_to_uvchr_error(const U8 * s,STRLEN curlen,STRLEN * retlen,const U32 flags,U32 * errors)1333 Perl_utf8n_to_uvchr_error(const U8 *s,
1334 STRLEN curlen,
1335 STRLEN *retlen,
1336 const U32 flags,
1337 U32 * errors)
1338 {
1339 PERL_ARGS_ASSERT_UTF8N_TO_UVCHR_ERROR;
1340
1341 return utf8n_to_uvchr_msgs(s, curlen, retlen, flags, errors, NULL);
1342 }
1343
1344 /*
1345
1346 =for apidoc utf8n_to_uvchr_msgs
1347
1348 THIS FUNCTION SHOULD BE USED IN ONLY VERY SPECIALIZED CIRCUMSTANCES.
1349 Most code should use L</utf8_to_uvchr_buf>() rather than call this
1350 directly.
1351
1352 This function is for code that needs to know what the precise malformation(s)
1353 are when an error is found, and wants the corresponding warning and/or error
1354 messages to be returned to the caller rather than be displayed. All messages
1355 that would have been displayed if all lexical warnings are enabled will be
1356 returned.
1357
1358 It is just like C<L</utf8n_to_uvchr_error>> but it takes an extra parameter
1359 placed after all the others, C<msgs>. If this parameter is 0, this function
1360 behaves identically to C<L</utf8n_to_uvchr_error>>. Otherwise, C<msgs> should
1361 be a pointer to an C<AV *> variable, in which this function creates a new AV to
1362 contain any appropriate messages. The elements of the array are ordered so
1363 that the first message that would have been displayed is in the 0th element,
1364 and so on. Each element is a hash with three key-value pairs, as follows:
1365
1366 =over 4
1367
1368 =item C<text>
1369
1370 The text of the message as a C<SVpv>.
1371
1372 =item C<warn_categories>
1373
1374 The warning category (or categories) packed into a C<SVuv>.
1375
1376 =item C<flag>
1377
1378 A single flag bit associated with this message, in a C<SVuv>.
1379 The bit corresponds to some bit in the C<*errors> return value,
1380 such as C<UTF8_GOT_LONG>.
1381
1382 =back
1383
1384 It's important to note that specifying this parameter as non-null will cause
1385 any warnings this function would otherwise generate to be suppressed, and
1386 instead be placed in C<*msgs>. The caller can check the lexical warnings state
1387 (or not) when choosing what to do with the returned messages.
1388
1389 If the flag C<UTF8_CHECK_ONLY> is passed, no warnings are generated, and hence
1390 no AV is created.
1391
1392 The caller, of course, is responsible for freeing any returned AV.
1393
1394 =cut
1395 */
1396
1397 UV
Perl__utf8n_to_uvchr_msgs_helper(const U8 * s,STRLEN curlen,STRLEN * retlen,const U32 flags,U32 * errors,AV ** msgs)1398 Perl__utf8n_to_uvchr_msgs_helper(const U8 *s,
1399 STRLEN curlen,
1400 STRLEN *retlen,
1401 const U32 flags,
1402 U32 * errors,
1403 AV ** msgs)
1404 {
1405 const U8 * const s0 = s;
1406 const U8 * send = s0 + curlen;
1407 U32 possible_problems; /* A bit is set here for each potential problem
1408 found as we go along */
1409 UV uv;
1410 STRLEN expectlen; /* How long should this sequence be? */
1411 STRLEN avail_len; /* When input is too short, gives what that is */
1412 U32 discard_errors; /* Used to save branches when 'errors' is NULL; this
1413 gets set and discarded */
1414
1415 /* The below are used only if there is both an overlong malformation and a
1416 * too short one. Otherwise the first two are set to 's0' and 'send', and
1417 * the third not used at all */
1418 U8 * adjusted_s0;
1419 U8 temp_char_buf[UTF8_MAXBYTES + 1]; /* Used to avoid a Newx in this
1420 routine; see [perl #130921] */
1421 UV uv_so_far;
1422 dTHX;
1423
1424 PERL_ARGS_ASSERT__UTF8N_TO_UVCHR_MSGS_HELPER;
1425
1426 /* Here, is one of: a) malformed; b) a problematic code point (surrogate,
1427 * non-unicode, or nonchar); or c) on ASCII platforms, one of the Hangul
1428 * syllables that the dfa doesn't properly handle. Quickly dispose of the
1429 * final case. */
1430
1431 /* Each of the affected Hanguls starts with \xED */
1432
1433 if (is_HANGUL_ED_utf8_safe(s0, send)) { /* Always false on EBCDIC */
1434 if (retlen) {
1435 *retlen = 3;
1436 }
1437 if (errors) {
1438 *errors = 0;
1439 }
1440 if (msgs) {
1441 *msgs = NULL;
1442 }
1443
1444 return ((0xED & UTF_START_MASK(3)) << (2 * UTF_ACCUMULATION_SHIFT))
1445 | ((s0[1] & UTF_CONTINUATION_MASK) << UTF_ACCUMULATION_SHIFT)
1446 | (s0[2] & UTF_CONTINUATION_MASK);
1447 }
1448
1449 /* In conjunction with the exhaustive tests that can be enabled in
1450 * APItest/t/utf8_warn_base.pl, this can make sure the dfa does precisely
1451 * what it is intended to do, and that no flaws in it are masked by
1452 * dropping down and executing the code below
1453 assert(! isUTF8_CHAR(s0, send)
1454 || UTF8_IS_SURROGATE(s0, send)
1455 || UTF8_IS_SUPER(s0, send)
1456 || UTF8_IS_NONCHAR(s0,send));
1457 */
1458
1459 s = s0;
1460 possible_problems = 0;
1461 expectlen = 0;
1462 avail_len = 0;
1463 discard_errors = 0;
1464 adjusted_s0 = (U8 *) s0;
1465 uv_so_far = 0;
1466
1467 if (errors) {
1468 *errors = 0;
1469 }
1470 else {
1471 errors = &discard_errors;
1472 }
1473
1474 /* The order of malformation tests here is important. We should consume as
1475 * few bytes as possible in order to not skip any valid character. This is
1476 * required by the Unicode Standard (section 3.9 of Unicode 6.0); see also
1477 * https://unicode.org/reports/tr36 for more discussion as to why. For
1478 * example, once we've done a UTF8SKIP, we can tell the expected number of
1479 * bytes, and could fail right off the bat if the input parameters indicate
1480 * that there are too few available. But it could be that just that first
1481 * byte is garbled, and the intended character occupies fewer bytes. If we
1482 * blindly assumed that the first byte is correct, and skipped based on
1483 * that number, we could skip over a valid input character. So instead, we
1484 * always examine the sequence byte-by-byte.
1485 *
1486 * We also should not consume too few bytes, otherwise someone could inject
1487 * things. For example, an input could be deliberately designed to
1488 * overflow, and if this code bailed out immediately upon discovering that,
1489 * returning to the caller C<*retlen> pointing to the very next byte (one
1490 * which is actually part of the overflowing sequence), that could look
1491 * legitimate to the caller, which could discard the initial partial
1492 * sequence and process the rest, inappropriately.
1493 *
1494 * Some possible input sequences are malformed in more than one way. This
1495 * function goes to lengths to try to find all of them. This is necessary
1496 * for correctness, as the inputs may allow one malformation but not
1497 * another, and if we abandon searching for others after finding the
1498 * allowed one, we could allow in something that shouldn't have been.
1499 */
1500
1501 if (UNLIKELY(curlen == 0)) {
1502 possible_problems |= UTF8_GOT_EMPTY;
1503 curlen = 0;
1504 uv = UNICODE_REPLACEMENT;
1505 goto ready_to_handle_errors;
1506 }
1507
1508 /* We now know we can examine the first byte of the input */
1509 expectlen = UTF8SKIP(s);
1510 uv = *s;
1511
1512 /* A well-formed UTF-8 character, as the vast majority of calls to this
1513 * function will be for, has this expected length. For efficiency, set
1514 * things up here to return it. It will be overridden only in those rare
1515 * cases where a malformation is found */
1516 if (retlen) {
1517 *retlen = expectlen;
1518 }
1519
1520 /* A continuation character can't start a valid sequence */
1521 if (UNLIKELY(UTF8_IS_CONTINUATION(uv))) {
1522 possible_problems |= UTF8_GOT_CONTINUATION;
1523 curlen = 1;
1524 uv = UNICODE_REPLACEMENT;
1525 goto ready_to_handle_errors;
1526 }
1527
1528 /* Here is not a continuation byte, nor an invariant. The only thing left
1529 * is a start byte (possibly for an overlong). (We can't use UTF8_IS_START
1530 * because it excludes start bytes like \xC0 that always lead to
1531 * overlongs.) */
1532
1533 /* Convert to I8 on EBCDIC (no-op on ASCII), then remove the leading bits
1534 * that indicate the number of bytes in the character's whole UTF-8
1535 * sequence, leaving just the bits that are part of the value. */
1536 uv = NATIVE_UTF8_TO_I8(uv) & UTF_START_MASK(expectlen);
1537
1538 /* Setup the loop end point, making sure to not look past the end of the
1539 * input string, and flag it as too short if the size isn't big enough. */
1540 if (UNLIKELY(curlen < expectlen)) {
1541 possible_problems |= UTF8_GOT_SHORT;
1542 avail_len = curlen;
1543 }
1544 else {
1545 send = (U8*) s0 + expectlen;
1546 }
1547
1548 /* Now, loop through the remaining bytes in the character's sequence,
1549 * accumulating each into the working value as we go. */
1550 for (s = s0 + 1; s < send; s++) {
1551 if (LIKELY(UTF8_IS_CONTINUATION(*s))) {
1552 uv = UTF8_ACCUMULATE(uv, *s);
1553 continue;
1554 }
1555
1556 /* Here, found a non-continuation before processing all expected bytes.
1557 * This byte indicates the beginning of a new character, so quit, even
1558 * if allowing this malformation. */
1559 possible_problems |= UTF8_GOT_NON_CONTINUATION;
1560 break;
1561 } /* End of loop through the character's bytes */
1562
1563 /* Save how many bytes were actually in the character */
1564 curlen = s - s0;
1565
1566 /* Note that there are two types of too-short malformation. One is when
1567 * there is actual wrong data before the normal termination of the
1568 * sequence. The other is that the sequence wasn't complete before the end
1569 * of the data we are allowed to look at, based on the input 'curlen'.
1570 * This means that we were passed data for a partial character, but it is
1571 * valid as far as we saw. The other is definitely invalid. This
1572 * distinction could be important to a caller, so the two types are kept
1573 * separate.
1574 *
1575 * A convenience macro that matches either of the too-short conditions. */
1576 # define UTF8_GOT_TOO_SHORT (UTF8_GOT_SHORT|UTF8_GOT_NON_CONTINUATION)
1577
1578 if (UNLIKELY(possible_problems & UTF8_GOT_TOO_SHORT)) {
1579 uv_so_far = uv;
1580 uv = UNICODE_REPLACEMENT;
1581 }
1582
1583 /* Check for overflow. The algorithm requires us to not look past the end
1584 * of the current character, even if partial, so the upper limit is 's' */
1585 if (UNLIKELY(0 < does_utf8_overflow(s0, s,
1586 1 /* Do consider overlongs */
1587 )))
1588 {
1589 possible_problems |= UTF8_GOT_OVERFLOW;
1590 uv = UNICODE_REPLACEMENT;
1591 }
1592
1593 /* Check for overlong. If no problems so far, 'uv' is the correct code
1594 * point value. Simply see if it is expressible in fewer bytes. Otherwise
1595 * we must look at the UTF-8 byte sequence itself to see if it is for an
1596 * overlong */
1597 if ( ( LIKELY(! possible_problems)
1598 && UNLIKELY(expectlen > (STRLEN) OFFUNISKIP(uv)))
1599 || ( UNLIKELY(possible_problems)
1600 && ( UNLIKELY(! UTF8_IS_START(*s0))
1601 || (UNLIKELY(0 < is_utf8_overlong(s0, s - s0))))))
1602 {
1603 possible_problems |= UTF8_GOT_LONG;
1604
1605 if ( UNLIKELY( possible_problems & UTF8_GOT_TOO_SHORT)
1606
1607 /* The calculation in the 'true' branch of this 'if'
1608 * below won't work if overflows, and isn't needed
1609 * anyway. Further below we handle all overflow
1610 * cases */
1611 && LIKELY(! (possible_problems & UTF8_GOT_OVERFLOW)))
1612 {
1613 UV min_uv = uv_so_far;
1614 STRLEN i;
1615
1616 /* Here, the input is both overlong and is missing some trailing
1617 * bytes. There is no single code point it could be for, but there
1618 * may be enough information present to determine if what we have
1619 * so far is for an unallowed code point, such as for a surrogate.
1620 * The code further below has the intelligence to determine this,
1621 * but just for non-overlong UTF-8 sequences. What we do here is
1622 * calculate the smallest code point the input could represent if
1623 * there were no too short malformation. Then we compute and save
1624 * the UTF-8 for that, which is what the code below looks at
1625 * instead of the raw input. It turns out that the smallest such
1626 * code point is all we need. */
1627 for (i = curlen; i < expectlen; i++) {
1628 min_uv = UTF8_ACCUMULATE(min_uv,
1629 I8_TO_NATIVE_UTF8(UTF_MIN_CONTINUATION_BYTE));
1630 }
1631
1632 adjusted_s0 = temp_char_buf;
1633 (void) uvoffuni_to_utf8_flags(adjusted_s0, min_uv, 0);
1634 }
1635 }
1636
1637 /* Here, we have found all the possible problems, except for when the input
1638 * is for a problematic code point not allowed by the input parameters. */
1639
1640 /* uv is valid for overlongs */
1641 if ( ( ( LIKELY(! (possible_problems & ~UTF8_GOT_LONG))
1642 && isUNICODE_POSSIBLY_PROBLEMATIC(uv))
1643 || ( UNLIKELY(possible_problems)
1644
1645 /* if overflow, we know without looking further
1646 * precisely which of the problematic types it is,
1647 * and we deal with those in the overflow handling
1648 * code */
1649 && LIKELY(! (possible_problems & UTF8_GOT_OVERFLOW))
1650 && ( isUTF8_POSSIBLY_PROBLEMATIC(*adjusted_s0)
1651 || UNLIKELY(UTF8_IS_PERL_EXTENDED(s0)))))
1652 && ((flags & ( UTF8_DISALLOW_NONCHAR
1653 |UTF8_DISALLOW_SURROGATE
1654 |UTF8_DISALLOW_SUPER
1655 |UTF8_DISALLOW_PERL_EXTENDED
1656 |UTF8_WARN_NONCHAR
1657 |UTF8_WARN_SURROGATE
1658 |UTF8_WARN_SUPER
1659 |UTF8_WARN_PERL_EXTENDED))))
1660 {
1661 /* If there were no malformations, or the only malformation is an
1662 * overlong, 'uv' is valid */
1663 if (LIKELY(! (possible_problems & ~UTF8_GOT_LONG))) {
1664 if (UNLIKELY(UNICODE_IS_SURROGATE(uv))) {
1665 possible_problems |= UTF8_GOT_SURROGATE;
1666 }
1667 else if (UNLIKELY(UNICODE_IS_SUPER(uv))) {
1668 possible_problems |= UTF8_GOT_SUPER;
1669 }
1670 else if (UNLIKELY(UNICODE_IS_NONCHAR(uv))) {
1671 possible_problems |= UTF8_GOT_NONCHAR;
1672 }
1673 }
1674 else { /* Otherwise, need to look at the source UTF-8, possibly
1675 adjusted to be non-overlong */
1676
1677 if (UNLIKELY(NATIVE_UTF8_TO_I8(*adjusted_s0)
1678 > UTF_START_BYTE_110000_))
1679 {
1680 possible_problems |= UTF8_GOT_SUPER;
1681 }
1682 else if (curlen > 1) {
1683 if (UNLIKELY( NATIVE_UTF8_TO_I8(*adjusted_s0)
1684 == UTF_START_BYTE_110000_
1685 && NATIVE_UTF8_TO_I8(*(adjusted_s0 + 1))
1686 >= UTF_FIRST_CONT_BYTE_110000_))
1687 {
1688 possible_problems |= UTF8_GOT_SUPER;
1689 }
1690 else if (UNLIKELY(is_SURROGATE_utf8(adjusted_s0))) {
1691 possible_problems |= UTF8_GOT_SURROGATE;
1692 }
1693 }
1694
1695 /* We need a complete well-formed UTF-8 character to discern
1696 * non-characters, so can't look for them here */
1697 }
1698 }
1699
1700 ready_to_handle_errors:
1701
1702 /* At this point:
1703 * curlen contains the number of bytes in the sequence that
1704 * this call should advance the input by.
1705 * avail_len gives the available number of bytes passed in, but
1706 * only if this is less than the expected number of
1707 * bytes, based on the code point's start byte.
1708 * possible_problems is 0 if there weren't any problems; otherwise a bit
1709 * is set in it for each potential problem found.
1710 * uv contains the code point the input sequence
1711 * represents; or if there is a problem that prevents
1712 * a well-defined value from being computed, it is
1713 * some substitute value, typically the REPLACEMENT
1714 * CHARACTER.
1715 * s0 points to the first byte of the character
1716 * s points to just after where we left off processing
1717 * the character
1718 * send points to just after where that character should
1719 * end, based on how many bytes the start byte tells
1720 * us should be in it, but no further than s0 +
1721 * avail_len
1722 */
1723
1724 if (UNLIKELY(possible_problems)) {
1725 bool disallowed = FALSE;
1726 const U32 orig_problems = possible_problems;
1727
1728 if (msgs) {
1729 *msgs = NULL;
1730 }
1731
1732 while (possible_problems) { /* Handle each possible problem */
1733 U32 pack_warn = 0;
1734 char * message = NULL;
1735 U32 this_flag_bit = 0;
1736
1737 /* Each 'if' clause handles one problem. They are ordered so that
1738 * the first ones' messages will be displayed before the later
1739 * ones; this is kinda in decreasing severity order. But the
1740 * overlong must come last, as it changes 'uv' looked at by the
1741 * others */
1742 if (possible_problems & UTF8_GOT_OVERFLOW) {
1743
1744 /* Overflow means also got a super and are using Perl's
1745 * extended UTF-8, but we handle all three cases here */
1746 possible_problems
1747 &= ~(UTF8_GOT_OVERFLOW|UTF8_GOT_SUPER|UTF8_GOT_PERL_EXTENDED);
1748 *errors |= UTF8_GOT_OVERFLOW;
1749
1750 /* But the API says we flag all errors found */
1751 if (flags & (UTF8_WARN_SUPER|UTF8_DISALLOW_SUPER)) {
1752 *errors |= UTF8_GOT_SUPER;
1753 }
1754 if (flags
1755 & (UTF8_WARN_PERL_EXTENDED|UTF8_DISALLOW_PERL_EXTENDED))
1756 {
1757 *errors |= UTF8_GOT_PERL_EXTENDED;
1758 }
1759
1760 /* Disallow if any of the three categories say to */
1761 if ( ! (flags & UTF8_ALLOW_OVERFLOW)
1762 || (flags & ( UTF8_DISALLOW_SUPER
1763 |UTF8_DISALLOW_PERL_EXTENDED)))
1764 {
1765 disallowed = TRUE;
1766 }
1767
1768 /* Likewise, warn if any say to */
1769 if ( ! (flags & UTF8_ALLOW_OVERFLOW)
1770 || (flags & (UTF8_WARN_SUPER|UTF8_WARN_PERL_EXTENDED)))
1771 {
1772
1773 /* The warnings code explicitly says it doesn't handle the
1774 * case of packWARN2 and two categories which have
1775 * parent-child relationship. Even if it works now to
1776 * raise the warning if either is enabled, it wouldn't
1777 * necessarily do so in the future. We output (only) the
1778 * most dire warning */
1779 if (! (flags & UTF8_CHECK_ONLY)) {
1780 if (msgs || ckWARN_d(WARN_UTF8)) {
1781 pack_warn = packWARN(WARN_UTF8);
1782 }
1783 else if (msgs || ckWARN_d(WARN_NON_UNICODE)) {
1784 pack_warn = packWARN(WARN_NON_UNICODE);
1785 }
1786 if (pack_warn) {
1787 message = Perl_form(aTHX_ "%s: %s (overflows)",
1788 malformed_text,
1789 _byte_dump_string(s0, curlen, 0));
1790 this_flag_bit = UTF8_GOT_OVERFLOW;
1791 }
1792 }
1793 }
1794 }
1795 else if (possible_problems & UTF8_GOT_EMPTY) {
1796 possible_problems &= ~UTF8_GOT_EMPTY;
1797 *errors |= UTF8_GOT_EMPTY;
1798
1799 if (! (flags & UTF8_ALLOW_EMPTY)) {
1800
1801 /* This so-called malformation is now treated as a bug in
1802 * the caller. If you have nothing to decode, skip calling
1803 * this function */
1804 assert(0);
1805
1806 disallowed = TRUE;
1807 if ( (msgs
1808 || ckWARN_d(WARN_UTF8)) && ! (flags & UTF8_CHECK_ONLY))
1809 {
1810 pack_warn = packWARN(WARN_UTF8);
1811 message = Perl_form(aTHX_ "%s (empty string)",
1812 malformed_text);
1813 this_flag_bit = UTF8_GOT_EMPTY;
1814 }
1815 }
1816 }
1817 else if (possible_problems & UTF8_GOT_CONTINUATION) {
1818 possible_problems &= ~UTF8_GOT_CONTINUATION;
1819 *errors |= UTF8_GOT_CONTINUATION;
1820
1821 if (! (flags & UTF8_ALLOW_CONTINUATION)) {
1822 disallowed = TRUE;
1823 if (( msgs
1824 || ckWARN_d(WARN_UTF8)) && ! (flags & UTF8_CHECK_ONLY))
1825 {
1826 pack_warn = packWARN(WARN_UTF8);
1827 message = Perl_form(aTHX_
1828 "%s: %s (unexpected continuation byte 0x%02x,"
1829 " with no preceding start byte)",
1830 malformed_text,
1831 _byte_dump_string(s0, 1, 0), *s0);
1832 this_flag_bit = UTF8_GOT_CONTINUATION;
1833 }
1834 }
1835 }
1836 else if (possible_problems & UTF8_GOT_SHORT) {
1837 possible_problems &= ~UTF8_GOT_SHORT;
1838 *errors |= UTF8_GOT_SHORT;
1839
1840 if (! (flags & UTF8_ALLOW_SHORT)) {
1841 disallowed = TRUE;
1842 if (( msgs
1843 || ckWARN_d(WARN_UTF8)) && ! (flags & UTF8_CHECK_ONLY))
1844 {
1845 pack_warn = packWARN(WARN_UTF8);
1846 message = Perl_form(aTHX_
1847 "%s: %s (too short; %d byte%s available, need %d)",
1848 malformed_text,
1849 _byte_dump_string(s0, send - s0, 0),
1850 (int)avail_len,
1851 avail_len == 1 ? "" : "s",
1852 (int)expectlen);
1853 this_flag_bit = UTF8_GOT_SHORT;
1854 }
1855 }
1856
1857 }
1858 else if (possible_problems & UTF8_GOT_NON_CONTINUATION) {
1859 possible_problems &= ~UTF8_GOT_NON_CONTINUATION;
1860 *errors |= UTF8_GOT_NON_CONTINUATION;
1861
1862 if (! (flags & UTF8_ALLOW_NON_CONTINUATION)) {
1863 disallowed = TRUE;
1864 if (( msgs
1865 || ckWARN_d(WARN_UTF8)) && ! (flags & UTF8_CHECK_ONLY))
1866 {
1867
1868 /* If we don't know for sure that the input length is
1869 * valid, avoid as much as possible reading past the
1870 * end of the buffer */
1871 int printlen = (flags & _UTF8_NO_CONFIDENCE_IN_CURLEN)
1872 ? (int) (s - s0)
1873 : (int) (send - s0);
1874 pack_warn = packWARN(WARN_UTF8);
1875 message = Perl_form(aTHX_ "%s",
1876 unexpected_non_continuation_text(s0,
1877 printlen,
1878 s - s0,
1879 (int) expectlen));
1880 this_flag_bit = UTF8_GOT_NON_CONTINUATION;
1881 }
1882 }
1883 }
1884 else if (possible_problems & UTF8_GOT_SURROGATE) {
1885 possible_problems &= ~UTF8_GOT_SURROGATE;
1886
1887 if (flags & UTF8_WARN_SURROGATE) {
1888 *errors |= UTF8_GOT_SURROGATE;
1889
1890 if ( ! (flags & UTF8_CHECK_ONLY)
1891 && (msgs || ckWARN_d(WARN_SURROGATE)))
1892 {
1893 pack_warn = packWARN(WARN_SURROGATE);
1894
1895 /* These are the only errors that can occur with a
1896 * surrogate when the 'uv' isn't valid */
1897 if (orig_problems & UTF8_GOT_TOO_SHORT) {
1898 message = Perl_form(aTHX_
1899 "UTF-16 surrogate (any UTF-8 sequence that"
1900 " starts with \"%s\" is for a surrogate)",
1901 _byte_dump_string(s0, curlen, 0));
1902 }
1903 else {
1904 message = Perl_form(aTHX_ surrogate_cp_format, uv);
1905 }
1906 this_flag_bit = UTF8_GOT_SURROGATE;
1907 }
1908 }
1909
1910 if (flags & UTF8_DISALLOW_SURROGATE) {
1911 disallowed = TRUE;
1912 *errors |= UTF8_GOT_SURROGATE;
1913 }
1914 }
1915 else if (possible_problems & UTF8_GOT_SUPER) {
1916 possible_problems &= ~UTF8_GOT_SUPER;
1917
1918 if (flags & UTF8_WARN_SUPER) {
1919 *errors |= UTF8_GOT_SUPER;
1920
1921 if ( ! (flags & UTF8_CHECK_ONLY)
1922 && (msgs || ckWARN_d(WARN_NON_UNICODE)))
1923 {
1924 pack_warn = packWARN(WARN_NON_UNICODE);
1925
1926 if (orig_problems & UTF8_GOT_TOO_SHORT) {
1927 message = Perl_form(aTHX_
1928 "Any UTF-8 sequence that starts with"
1929 " \"%s\" is for a non-Unicode code point,"
1930 " may not be portable",
1931 _byte_dump_string(s0, curlen, 0));
1932 }
1933 else {
1934 message = Perl_form(aTHX_ super_cp_format, uv);
1935 }
1936 this_flag_bit = UTF8_GOT_SUPER;
1937 }
1938 }
1939
1940 /* Test for Perl's extended UTF-8 after the regular SUPER ones,
1941 * and before possibly bailing out, so that the more dire
1942 * warning will override the regular one. */
1943 if (UNLIKELY(UTF8_IS_PERL_EXTENDED(s0))) {
1944 if ( ! (flags & UTF8_CHECK_ONLY)
1945 && (flags & (UTF8_WARN_PERL_EXTENDED|UTF8_WARN_SUPER))
1946 && (msgs || ( ckWARN_d(WARN_NON_UNICODE)
1947 || ckWARN(WARN_PORTABLE))))
1948 {
1949 pack_warn = packWARN2(WARN_NON_UNICODE, WARN_PORTABLE);
1950
1951 /* If it is an overlong that evaluates to a code point
1952 * that doesn't have to use the Perl extended UTF-8, it
1953 * still used it, and so we output a message that
1954 * doesn't refer to the code point. The same is true
1955 * if there was a SHORT malformation where the code
1956 * point is not valid. In that case, 'uv' will have
1957 * been set to the REPLACEMENT CHAR, and the message
1958 * below without the code point in it will be selected
1959 * */
1960 if (UNICODE_IS_PERL_EXTENDED(uv)) {
1961 message = Perl_form(aTHX_
1962 PL_extended_cp_format, uv);
1963 }
1964 else {
1965 message = Perl_form(aTHX_
1966 "Any UTF-8 sequence that starts with"
1967 " \"%s\" is a Perl extension, and"
1968 " so is not portable",
1969 _byte_dump_string(s0, curlen, 0));
1970 }
1971 this_flag_bit = UTF8_GOT_PERL_EXTENDED;
1972 }
1973
1974 if (flags & ( UTF8_WARN_PERL_EXTENDED
1975 |UTF8_DISALLOW_PERL_EXTENDED))
1976 {
1977 *errors |= UTF8_GOT_PERL_EXTENDED;
1978
1979 if (flags & UTF8_DISALLOW_PERL_EXTENDED) {
1980 disallowed = TRUE;
1981 }
1982 }
1983 }
1984
1985 if (flags & UTF8_DISALLOW_SUPER) {
1986 *errors |= UTF8_GOT_SUPER;
1987 disallowed = TRUE;
1988 }
1989 }
1990 else if (possible_problems & UTF8_GOT_NONCHAR) {
1991 possible_problems &= ~UTF8_GOT_NONCHAR;
1992
1993 if (flags & UTF8_WARN_NONCHAR) {
1994 *errors |= UTF8_GOT_NONCHAR;
1995
1996 if ( ! (flags & UTF8_CHECK_ONLY)
1997 && (msgs || ckWARN_d(WARN_NONCHAR)))
1998 {
1999 /* The code above should have guaranteed that we don't
2000 * get here with errors other than overlong */
2001 assert (! (orig_problems
2002 & ~(UTF8_GOT_LONG|UTF8_GOT_NONCHAR)));
2003
2004 pack_warn = packWARN(WARN_NONCHAR);
2005 message = Perl_form(aTHX_ nonchar_cp_format, uv);
2006 this_flag_bit = UTF8_GOT_NONCHAR;
2007 }
2008 }
2009
2010 if (flags & UTF8_DISALLOW_NONCHAR) {
2011 disallowed = TRUE;
2012 *errors |= UTF8_GOT_NONCHAR;
2013 }
2014 }
2015 else if (possible_problems & UTF8_GOT_LONG) {
2016 possible_problems &= ~UTF8_GOT_LONG;
2017 *errors |= UTF8_GOT_LONG;
2018
2019 if (flags & UTF8_ALLOW_LONG) {
2020
2021 /* We don't allow the actual overlong value, unless the
2022 * special extra bit is also set */
2023 if (! (flags & ( UTF8_ALLOW_LONG_AND_ITS_VALUE
2024 & ~UTF8_ALLOW_LONG)))
2025 {
2026 uv = UNICODE_REPLACEMENT;
2027 }
2028 }
2029 else {
2030 disallowed = TRUE;
2031
2032 if (( msgs
2033 || ckWARN_d(WARN_UTF8)) && ! (flags & UTF8_CHECK_ONLY))
2034 {
2035 pack_warn = packWARN(WARN_UTF8);
2036
2037 /* These error types cause 'uv' to be something that
2038 * isn't what was intended, so can't use it in the
2039 * message. The other error types either can't
2040 * generate an overlong, or else the 'uv' is valid */
2041 if (orig_problems &
2042 (UTF8_GOT_TOO_SHORT|UTF8_GOT_OVERFLOW))
2043 {
2044 message = Perl_form(aTHX_
2045 "%s: %s (any UTF-8 sequence that starts"
2046 " with \"%s\" is overlong which can and"
2047 " should be represented with a"
2048 " different, shorter sequence)",
2049 malformed_text,
2050 _byte_dump_string(s0, send - s0, 0),
2051 _byte_dump_string(s0, curlen, 0));
2052 }
2053 else {
2054 U8 tmpbuf[UTF8_MAXBYTES+1];
2055 const U8 * const e = uvoffuni_to_utf8_flags(tmpbuf,
2056 uv, 0);
2057 /* Don't use U+ for non-Unicode code points, which
2058 * includes those in the Latin1 range */
2059 const char * preface = ( UNICODE_IS_SUPER(uv)
2060 #ifdef EBCDIC
2061 || uv <= 0xFF
2062 #endif
2063 )
2064 ? "0x"
2065 : "U+";
2066 message = Perl_form(aTHX_
2067 "%s: %s (overlong; instead use %s to represent"
2068 " %s%0*" UVXf ")",
2069 malformed_text,
2070 _byte_dump_string(s0, send - s0, 0),
2071 _byte_dump_string(tmpbuf, e - tmpbuf, 0),
2072 preface,
2073 ((uv < 256) ? 2 : 4), /* Field width of 2 for
2074 small code points */
2075 UNI_TO_NATIVE(uv));
2076 }
2077 this_flag_bit = UTF8_GOT_LONG;
2078 }
2079 }
2080 } /* End of looking through the possible flags */
2081
2082 /* Display the message (if any) for the problem being handled in
2083 * this iteration of the loop */
2084 if (message) {
2085 if (msgs) {
2086 assert(this_flag_bit);
2087
2088 if (*msgs == NULL) {
2089 *msgs = newAV();
2090 }
2091
2092 av_push(*msgs, newRV_noinc((SV*) new_msg_hv(message,
2093 pack_warn,
2094 this_flag_bit)));
2095 }
2096 else if (PL_op)
2097 Perl_warner(aTHX_ pack_warn, "%s in %s", message,
2098 OP_DESC(PL_op));
2099 else
2100 Perl_warner(aTHX_ pack_warn, "%s", message);
2101 }
2102 } /* End of 'while (possible_problems)' */
2103
2104 /* Since there was a possible problem, the returned length may need to
2105 * be changed from the one stored at the beginning of this function.
2106 * Instead of trying to figure out if it has changed, just do it. */
2107 if (retlen) {
2108 *retlen = curlen;
2109 }
2110
2111 if (disallowed) {
2112 if (flags & UTF8_CHECK_ONLY && retlen) {
2113 *retlen = ((STRLEN) -1);
2114 }
2115 return 0;
2116 }
2117 }
2118
2119 return UNI_TO_NATIVE(uv);
2120 }
2121
2122 /*
2123 =for apidoc utf8_to_uvchr_buf
2124
2125 Returns the native code point of the first character in the string C<s> which
2126 is assumed to be in UTF-8 encoding; C<send> points to 1 beyond the end of C<s>.
2127 C<*retlen> will be set to the length, in bytes, of that character.
2128
2129 If C<s> does not point to a well-formed UTF-8 character and UTF8 warnings are
2130 enabled, zero is returned and C<*retlen> is set (if C<retlen> isn't
2131 C<NULL>) to -1. If those warnings are off, the computed value, if well-defined
2132 (or the Unicode REPLACEMENT CHARACTER if not), is silently returned, and
2133 C<*retlen> is set (if C<retlen> isn't C<NULL>) so that (S<C<s> + C<*retlen>>) is
2134 the next possible position in C<s> that could begin a non-malformed character.
2135 See L</utf8n_to_uvchr> for details on when the REPLACEMENT CHARACTER is
2136 returned.
2137
2138 =cut
2139
2140 Also implemented as a macro in utf8.h
2141
2142 */
2143
2144
2145 UV
Perl_utf8_to_uvchr_buf(pTHX_ const U8 * s,const U8 * send,STRLEN * retlen)2146 Perl_utf8_to_uvchr_buf(pTHX_ const U8 *s, const U8 *send, STRLEN *retlen)
2147 {
2148 PERL_ARGS_ASSERT_UTF8_TO_UVCHR_BUF;
2149
2150 return utf8_to_uvchr_buf_helper(s, send, retlen);
2151 }
2152
2153 /*
2154 =for apidoc utf8_length
2155
2156 Returns the number of characters in the sequence of UTF-8-encoded bytes starting
2157 at C<s> and ending at the byte just before C<e>. If <s> and <e> point to the
2158 same place, it returns 0 with no warning raised.
2159
2160 If C<e E<lt> s> or if the scan would end up past C<e>, it raises a UTF8 warning
2161 and returns the number of valid characters.
2162
2163 =cut
2164
2165 For long strings we process the input word-at-a-time, and count
2166 continuations, instead of otherwise counting characters and using UTF8SKIP
2167 to find the next one. If our input were 13-byte characters, the per-word
2168 would be a loser, as we would be doing things in 8 byte chunks (or 4 on a
2169 32-bit platform). But the maximum legal Unicode code point is 4 bytes, and
2170 most text will have a significant number of 1 and 2 byte characters, so the
2171 per-word is generally a winner.
2172
2173 There are start-up and finish costs with the per-word method, so we use the
2174 standard method unless the input has a relatively large length.
2175 */
2176
2177 STRLEN
Perl_utf8_length(pTHX_ const U8 * const s0,const U8 * const e)2178 Perl_utf8_length(pTHX_ const U8 * const s0, const U8 * const e)
2179 {
2180 STRLEN continuations = 0;
2181 STRLEN len = 0;
2182 const U8 * s = s0;
2183
2184 PERL_ARGS_ASSERT_UTF8_LENGTH;
2185
2186 /* For EBCDCIC and short strings, we count the characters. The boundary
2187 * was determined by eyeballing the output of Porting/bench.pl and
2188 * choosing a number where the continuations method gave better results (on
2189 * a 64 bit system, khw not having access to a 32 bit system with
2190 * cachegrind). The number isn't critical, as at these sizes, the total
2191 * time spent isn't large either way */
2192
2193 #ifndef EBCDIC
2194
2195 if (e - s0 < 96)
2196
2197 #endif
2198
2199 {
2200 while (s < e) { /* Count characters directly */
2201
2202 /* Take extra care to not exceed 'e' (which would be undefined
2203 * behavior) should the input be malformed, with a partial
2204 * character at the end */
2205 Ptrdiff_t expected_byte_count = UTF8SKIP(s);
2206 if (UNLIKELY(e - s < expected_byte_count)) {
2207 goto warn_and_return;
2208 }
2209
2210 len++;
2211 s += expected_byte_count;
2212 }
2213
2214 if (LIKELY(e == s)) {
2215 return len;
2216 }
2217
2218 warn_and_return:
2219 if (ckWARN_d(WARN_UTF8)) {
2220 if (PL_op)
2221 Perl_warner(aTHX_ packWARN(WARN_UTF8),
2222 "%s in %s", unees, OP_DESC(PL_op));
2223 else
2224 Perl_warner(aTHX_ packWARN(WARN_UTF8), "%s", unees);
2225 }
2226
2227 return s - s0;
2228 }
2229
2230 #ifndef EBCDIC
2231
2232 /* Count continuations, word-at-a-time.
2233 *
2234 * We need to stop before the final start character in order to
2235 * preserve the limited error checking that's always been done */
2236 const U8 * e_limit = e - UTF8_MAXBYTES;
2237
2238 /* Points to the first byte >=s which is positioned at a word boundary. If
2239 * s is on a word boundary, it is s, otherwise it is to the next word. */
2240 const U8 * partial_word_end = s + PERL_WORDSIZE * PERL_IS_SUBWORD_ADDR(s)
2241 - (PTR2nat(s) & PERL_WORD_BOUNDARY_MASK);
2242
2243 /* Process up to a full word boundary. */
2244 while (s < partial_word_end) {
2245 const Size_t skip = UTF8SKIP(s);
2246
2247 continuations += skip - 1;
2248 s += skip;
2249 }
2250
2251 /* Adjust back down any overshoot */
2252 continuations -= s - partial_word_end;
2253 s = partial_word_end;
2254
2255 do { /* Process per-word */
2256
2257 /* The idea for counting continuation bytes came from
2258 * http://www.daemonology.net/blog/2008-06-05-faster-utf8-strlen.html
2259 * One thing it does that this doesn't is to prefetch the buffer
2260 * __builtin_prefetch(&s[256], 0, 0);
2261 *
2262 * A continuation byte has the upper 2 bits be '10', and the rest
2263 * dont-cares. The VARIANTS mask zeroes out all but the upper bit of
2264 * each byte in the word. That gets shifted to the byte's lowest bit,
2265 * and 'anded' with the complement of the 2nd highest bit of the byte,
2266 * which has also been shifted to that position. Hence the bit in that
2267 * position will be 1 iff the upper bit is 1 and the next one is 0. We
2268 * then use the same integer multiplcation and shifting that are used
2269 * in variant_under_utf8_count() to count how many of those are set in
2270 * the word. */
2271
2272 continuations += (((((* (const PERL_UINTMAX_T *) s)
2273 & PERL_VARIANTS_WORD_MASK) >> 7)
2274 & (((~ (* (const PERL_UINTMAX_T *) s))) >> 6))
2275 * PERL_COUNT_MULTIPLIER)
2276 >> ((PERL_WORDSIZE - 1) * CHARBITS);
2277 s += PERL_WORDSIZE;
2278 } while (s + PERL_WORDSIZE <= e_limit);
2279
2280 /* Process remainder per-byte */
2281 while (s < e) {
2282 if (UTF8_IS_CONTINUATION(*s)) {
2283 continuations++;
2284 s++;
2285 continue;
2286 }
2287
2288 /* Here is a starter byte. Use UTF8SKIP from now on */
2289 do {
2290 Ptrdiff_t expected_byte_count = UTF8SKIP(s);
2291 if (UNLIKELY(e - s < expected_byte_count)) {
2292 break;
2293 }
2294
2295 continuations += expected_byte_count- 1;
2296 s += expected_byte_count;
2297 } while (s < e);
2298
2299 break;
2300 }
2301
2302 # endif
2303
2304 if (LIKELY(e == s)) {
2305 return s - s0 - continuations;
2306 }
2307
2308 /* Convert to characters */
2309 s -= continuations;
2310
2311 goto warn_and_return;
2312 }
2313
2314 /*
2315 =for apidoc bytes_cmp_utf8
2316
2317 Compares the sequence of characters (stored as octets) in C<b>, C<blen> with the
2318 sequence of characters (stored as UTF-8)
2319 in C<u>, C<ulen>. Returns 0 if they are
2320 equal, -1 or -2 if the first string is less than the second string, +1 or +2
2321 if the first string is greater than the second string.
2322
2323 -1 or +1 is returned if the shorter string was identical to the start of the
2324 longer string. -2 or +2 is returned if
2325 there was a difference between characters
2326 within the strings.
2327
2328 =cut
2329 */
2330
2331 int
Perl_bytes_cmp_utf8(pTHX_ const U8 * b,STRLEN blen,const U8 * u,STRLEN ulen)2332 Perl_bytes_cmp_utf8(pTHX_ const U8 *b, STRLEN blen, const U8 *u, STRLEN ulen)
2333 {
2334 const U8 *const bend = b + blen;
2335 const U8 *const uend = u + ulen;
2336
2337 PERL_ARGS_ASSERT_BYTES_CMP_UTF8;
2338
2339 while (b < bend && u < uend) {
2340 U8 c = *u++;
2341 if (!UTF8_IS_INVARIANT(c)) {
2342 if (UTF8_IS_DOWNGRADEABLE_START(c)) {
2343 if (u < uend) {
2344 U8 c1 = *u++;
2345 if (UTF8_IS_CONTINUATION(c1)) {
2346 c = EIGHT_BIT_UTF8_TO_NATIVE(c, c1);
2347 } else {
2348 /* diag_listed_as: Malformed UTF-8 character%s */
2349 Perl_ck_warner_d(aTHX_ packWARN(WARN_UTF8),
2350 "%s %s%s",
2351 unexpected_non_continuation_text(u - 2, 2, 1, 2),
2352 PL_op ? " in " : "",
2353 PL_op ? OP_DESC(PL_op) : "");
2354 return -2;
2355 }
2356 } else {
2357 if (PL_op)
2358 Perl_ck_warner_d(aTHX_ packWARN(WARN_UTF8),
2359 "%s in %s", unees, OP_DESC(PL_op));
2360 else
2361 Perl_ck_warner_d(aTHX_ packWARN(WARN_UTF8), "%s", unees);
2362 return -2; /* Really want to return undef :-) */
2363 }
2364 } else {
2365 return -2;
2366 }
2367 }
2368 if (*b != c) {
2369 return *b < c ? -2 : +2;
2370 }
2371 ++b;
2372 }
2373
2374 if (b == bend && u == uend)
2375 return 0;
2376
2377 return b < bend ? +1 : -1;
2378 }
2379
2380 /*
2381 =for apidoc utf8_to_bytes
2382
2383 Converts a string C<"s"> of length C<*lenp> from UTF-8 into native byte encoding.
2384 Unlike L</bytes_to_utf8>, this over-writes the original string, and
2385 updates C<*lenp> to contain the new length.
2386 Returns zero on failure (leaving C<"s"> unchanged) setting C<*lenp> to -1.
2387
2388 Upon successful return, the number of variants in the string can be computed by
2389 having saved the value of C<*lenp> before the call, and subtracting the
2390 after-call value of C<*lenp> from it.
2391
2392 If you need a copy of the string, see L</bytes_from_utf8>.
2393
2394 =cut
2395 */
2396
2397 U8 *
Perl_utf8_to_bytes(pTHX_ U8 * s,STRLEN * lenp)2398 Perl_utf8_to_bytes(pTHX_ U8 *s, STRLEN *lenp)
2399 {
2400 U8 * first_variant;
2401
2402 PERL_ARGS_ASSERT_UTF8_TO_BYTES;
2403 PERL_UNUSED_CONTEXT;
2404
2405 /* This is a no-op if no variants at all in the input */
2406 if (is_utf8_invariant_string_loc(s, *lenp, (const U8 **) &first_variant)) {
2407 return s;
2408 }
2409
2410 /* Nothing before 'first_variant' needs to be changed, so start the real
2411 * work there */
2412
2413 U8 * const save = s;
2414 U8 * const send = s + *lenp;
2415 U8 * d;
2416
2417 #ifndef EBCDIC /* The below relies on the bit patterns of UTF-8 */
2418
2419 /* There is some start-up/tear-down overhead with this, so no real gain
2420 * unless the string is long enough. The current value is just a
2421 * guess. */
2422 if (*lenp > 5 * PERL_WORDSIZE) {
2423
2424 /* First, go through the string a word at-a-time to verify that it is
2425 * downgradable. If it contains any start byte besides C2 and C3, then
2426 * it isn't. */
2427
2428 const PERL_UINTMAX_T C0_mask = PERL_COUNT_MULTIPLIER * 0xC0;
2429 const PERL_UINTMAX_T C2_mask = PERL_COUNT_MULTIPLIER * 0xC2;
2430 const PERL_UINTMAX_T FE_mask = PERL_COUNT_MULTIPLIER * 0xFE;
2431
2432 /* Points to the first byte >=s which is positioned at a word boundary.
2433 * If s is on a word boundary, it is s, otherwise it is the first byte
2434 * of the next word. */
2435 U8 * partial_word_end = s + PERL_WORDSIZE * PERL_IS_SUBWORD_ADDR(s)
2436 - (PTR2nat(s) & PERL_WORD_BOUNDARY_MASK);
2437
2438 /* Here there is at least a full word beyond the first word boundary.
2439 * Process up to that boundary. */
2440 while (s < partial_word_end) {
2441 if (! UTF8_IS_INVARIANT(*s)) {
2442 if (! UTF8_IS_NEXT_CHAR_DOWNGRADEABLE(s, send)) {
2443 *lenp = ((STRLEN) -1);
2444 return NULL;
2445 }
2446 s++;
2447 }
2448 s++;
2449 }
2450
2451 /* Adjust back down any overshoot */
2452 s = partial_word_end;
2453
2454 /* Process per-word */
2455 do {
2456
2457 PERL_UINTMAX_T C2_C3_start_bytes;
2458
2459 /* First find the bytes that are start bytes. ANDing with
2460 * C0C0...C0 causes any start byte to become C0; any other byte
2461 * becomes something else. Then XORing with C0 causes any start
2462 * byte to become 0; all other bytes non-zero. */
2463 PERL_UINTMAX_T start_bytes
2464 = ((* (PERL_UINTMAX_T *) s) & C0_mask) ^ C0_mask;
2465
2466 /* These shifts causes the most significant bit to be set to 1 for
2467 * any bytes in the word that aren't completely 0. Hence after
2468 * these, only the start bytes have 0 in their msb */
2469 start_bytes |= start_bytes << 1;
2470 start_bytes |= start_bytes << 2;
2471 start_bytes |= start_bytes << 4;
2472
2473 /* When we complement, then AND with 8080...80, the start bytes
2474 * will have 1 in their msb, and all other bits are 0 */
2475 start_bytes = ~ start_bytes & PERL_VARIANTS_WORD_MASK;
2476
2477 /* Now repeat the procedure, but look for bytes that match only
2478 * C2-C3. */
2479 C2_C3_start_bytes = ((* (PERL_UINTMAX_T *) s) & FE_mask)
2480 ^ C2_mask;
2481 C2_C3_start_bytes |= C2_C3_start_bytes << 1;
2482 C2_C3_start_bytes |= C2_C3_start_bytes << 2;
2483 C2_C3_start_bytes |= C2_C3_start_bytes << 4;
2484 C2_C3_start_bytes = ~ C2_C3_start_bytes
2485 & PERL_VARIANTS_WORD_MASK;
2486
2487 /* Here, start_bytes has a 1 in the msb of each byte that has a
2488 * start_byte; And
2489 * C2_C3_start_bytes has a 1 in the msb of each byte that has a
2490 * start_byte of C2 or C3
2491 * If they're not equal, there are start bytes that aren't C2
2492 * nor C3, hence this is not downgradable */
2493 if (start_bytes != C2_C3_start_bytes) {
2494 *lenp = ((STRLEN) -1);
2495 return NULL;
2496 }
2497
2498 s += PERL_WORDSIZE;
2499 } while (s + PERL_WORDSIZE <= send);
2500
2501 /* If the final byte was a start byte, it means that the character
2502 * straddles two words, so back off one to start looking below at the
2503 * first byte of the character */
2504 if (s > first_variant && UTF8_IS_START(*(s-1))) {
2505 s--;
2506 }
2507 }
2508
2509 #endif
2510
2511 /* Do the straggler bytes beyond the final word boundary (or all bytes
2512 * in the case of EBCDIC) */
2513 while (s < send) {
2514 if (! UTF8_IS_INVARIANT(*s)) {
2515 if (! UTF8_IS_NEXT_CHAR_DOWNGRADEABLE(s, send)) {
2516 *lenp = ((STRLEN) -1);
2517 return NULL;
2518 }
2519 s++;
2520 }
2521 s++;
2522 }
2523
2524 /* Here, we passed the tests above. For the EBCDIC case, everything
2525 * was well-formed and can be downgraded to non-UTF8. For non-EBCDIC,
2526 * it means only that all start bytes were C2 or C3, hence any
2527 * well-formed sequences are downgradable. But we didn't test, for
2528 * example, that there weren't two C2's in a row. That means that in
2529 * the loop below, we have to be sure things are well-formed. Because
2530 * this is very very likely, and we don't care about having speedy
2531 * handling of malformed input, the loop proceeds as if well formed,
2532 * and should a malformed one come along, it undoes what it already has
2533 * done */
2534
2535 d = s = first_variant;
2536
2537 while (s < send) {
2538 U8 * s1;
2539
2540 if (UVCHR_IS_INVARIANT(*s)) {
2541 *d++ = *s++;
2542 continue;
2543 }
2544
2545 /* Here it is two-byte encoded. */
2546 if ( LIKELY(UTF8_IS_DOWNGRADEABLE_START(*s))
2547 && LIKELY(UTF8_IS_CONTINUATION((s[1]))))
2548 {
2549 U8 first_byte = *s++;
2550 *d++ = EIGHT_BIT_UTF8_TO_NATIVE(first_byte, *s);
2551 s++;
2552 continue;
2553 }
2554
2555 /* Here, it is malformed. This shouldn't happen on EBCDIC, and on
2556 * ASCII platforms, we know that the only start bytes in the text
2557 * are C2 and C3, and the code above has made sure that it doesn't
2558 * end with a start byte. That means the only malformations that
2559 * are possible are a start byte without a continuation (either
2560 * followed by another start byte or an invariant) or an unexpected
2561 * continuation.
2562 *
2563 * We have to undo all we've done before, back down to the first
2564 * UTF-8 variant. Note that each 2-byte variant we've done so far
2565 * (converted to single byte) slides things to the left one byte,
2566 * and so we have bytes that haven't been written over.
2567 *
2568 * Here, 'd' points to the next position to overwrite, and 's'
2569 * points to the first invalid byte. That means 'd's contents
2570 * haven't been changed yet, nor has anything else beyond it in the
2571 * string. In restoring to the original contents, we don't need to
2572 * do anything past (d-1).
2573 *
2574 * In particular, the bytes from 'd' to 's' have not been changed.
2575 * This loop uses a new variable 's1' (to avoid confusing 'source'
2576 * and 'destination') set to 'd', and moves 's' and 's1' in lock
2577 * step back so that afterwards, 's1' points to the first changed
2578 * byte that will be the source for the first byte (or bytes) at
2579 * 's' that need to be changed back. Note that s1 can expand to
2580 * two bytes */
2581 s1 = d;
2582 while (s >= d) {
2583 s--;
2584 if (! UVCHR_IS_INVARIANT(*s1)) {
2585 s--;
2586 }
2587 s1--;
2588 }
2589
2590 /* Do the changing back */
2591 while (s1 >= first_variant) {
2592 if (UVCHR_IS_INVARIANT(*s1)) {
2593 *s-- = *s1--;
2594 }
2595 else {
2596 *s-- = UTF8_EIGHT_BIT_LO(*s1);
2597 *s-- = UTF8_EIGHT_BIT_HI(*s1);
2598 s1--;
2599 }
2600 }
2601
2602 *lenp = ((STRLEN) -1);
2603 return NULL;
2604 }
2605
2606 /* Success! */
2607 *d = '\0';
2608 *lenp = d - save;
2609
2610 return save;
2611 }
2612
2613 /*
2614 =for apidoc bytes_from_utf8
2615
2616 Converts a potentially UTF-8 encoded string C<s> of length C<*lenp> into native
2617 byte encoding. On input, the boolean C<*is_utf8p> gives whether or not C<s> is
2618 actually encoded in UTF-8.
2619
2620 Unlike L</utf8_to_bytes> but like L</bytes_to_utf8>, this is non-destructive of
2621 the input string.
2622
2623 Do nothing if C<*is_utf8p> is 0, or if there are code points in the string
2624 not expressible in native byte encoding. In these cases, C<*is_utf8p> and
2625 C<*lenp> are unchanged, and the return value is the original C<s>.
2626
2627 Otherwise, C<*is_utf8p> is set to 0, and the return value is a pointer to a
2628 newly created string containing a downgraded copy of C<s>, and whose length is
2629 returned in C<*lenp>, updated. The new string is C<NUL>-terminated. The
2630 caller is responsible for arranging for the memory used by this string to get
2631 freed.
2632
2633 Upon successful return, the number of variants in the string can be computed by
2634 having saved the value of C<*lenp> before the call, and subtracting the
2635 after-call value of C<*lenp> from it.
2636
2637 =cut
2638
2639 There is a macro that avoids this function call, but this is retained for
2640 anyone who calls it with the Perl_ prefix */
2641
2642 U8 *
Perl_bytes_from_utf8(pTHX_ const U8 * s,STRLEN * lenp,bool * is_utf8p)2643 Perl_bytes_from_utf8(pTHX_ const U8 *s, STRLEN *lenp, bool *is_utf8p)
2644 {
2645 PERL_ARGS_ASSERT_BYTES_FROM_UTF8;
2646 PERL_UNUSED_CONTEXT;
2647
2648 return bytes_from_utf8_loc(s, lenp, is_utf8p, NULL);
2649 }
2650
2651 /*
2652 =for apidoc bytes_from_utf8_loc
2653
2654 Like C<L<perlapi/bytes_from_utf8>()>, but takes an extra parameter, a pointer
2655 to where to store the location of the first character in C<"s"> that cannot be
2656 converted to non-UTF8.
2657
2658 If that parameter is C<NULL>, this function behaves identically to
2659 C<bytes_from_utf8>.
2660
2661 Otherwise if C<*is_utf8p> is 0 on input, the function behaves identically to
2662 C<bytes_from_utf8>, except it also sets C<*first_non_downgradable> to C<NULL>.
2663
2664 Otherwise, the function returns a newly created C<NUL>-terminated string
2665 containing the non-UTF8 equivalent of the convertible first portion of
2666 C<"s">. C<*lenp> is set to its length, not including the terminating C<NUL>.
2667 If the entire input string was converted, C<*is_utf8p> is set to a FALSE value,
2668 and C<*first_non_downgradable> is set to C<NULL>.
2669
2670 Otherwise, C<*first_non_downgradable> is set to point to the first byte of the
2671 first character in the original string that wasn't converted. C<*is_utf8p> is
2672 unchanged. Note that the new string may have length 0.
2673
2674 Another way to look at it is, if C<*first_non_downgradable> is non-C<NULL> and
2675 C<*is_utf8p> is TRUE, this function starts at the beginning of C<"s"> and
2676 converts as many characters in it as possible stopping at the first one it
2677 finds that can't be converted to non-UTF-8. C<*first_non_downgradable> is
2678 set to point to that. The function returns the portion that could be converted
2679 in a newly created C<NUL>-terminated string, and C<*lenp> is set to its length,
2680 not including the terminating C<NUL>. If the very first character in the
2681 original could not be converted, C<*lenp> will be 0, and the new string will
2682 contain just a single C<NUL>. If the entire input string was converted,
2683 C<*is_utf8p> is set to FALSE and C<*first_non_downgradable> is set to C<NULL>.
2684
2685 Upon successful return, the number of variants in the converted portion of the
2686 string can be computed by having saved the value of C<*lenp> before the call,
2687 and subtracting the after-call value of C<*lenp> from it.
2688
2689 =cut
2690
2691
2692 */
2693
2694 U8 *
Perl_bytes_from_utf8_loc(const U8 * s,STRLEN * lenp,bool * is_utf8p,const U8 ** first_unconverted)2695 Perl_bytes_from_utf8_loc(const U8 *s, STRLEN *lenp, bool *is_utf8p, const U8** first_unconverted)
2696 {
2697 U8 *d;
2698 const U8 *original = s;
2699 U8 *converted_start;
2700 const U8 *send = s + *lenp;
2701
2702 PERL_ARGS_ASSERT_BYTES_FROM_UTF8_LOC;
2703
2704 if (! *is_utf8p) {
2705 if (first_unconverted) {
2706 *first_unconverted = NULL;
2707 }
2708
2709 return (U8 *) original;
2710 }
2711
2712 Newx(d, (*lenp) + 1, U8);
2713
2714 converted_start = d;
2715 while (s < send) {
2716 U8 c = *s++;
2717 if (! UTF8_IS_INVARIANT(c)) {
2718
2719 /* Then it is multi-byte encoded. If the code point is above 0xFF,
2720 * have to stop now */
2721 if (UNLIKELY (! UTF8_IS_NEXT_CHAR_DOWNGRADEABLE(s - 1, send))) {
2722 if (first_unconverted) {
2723 *first_unconverted = s - 1;
2724 goto finish_and_return;
2725 }
2726 else {
2727 Safefree(converted_start);
2728 return (U8 *) original;
2729 }
2730 }
2731
2732 c = EIGHT_BIT_UTF8_TO_NATIVE(c, *s);
2733 s++;
2734 }
2735 *d++ = c;
2736 }
2737
2738 /* Here, converted the whole of the input */
2739 *is_utf8p = FALSE;
2740 if (first_unconverted) {
2741 *first_unconverted = NULL;
2742 }
2743
2744 finish_and_return:
2745 *d = '\0';
2746 *lenp = d - converted_start;
2747
2748 /* Trim unused space */
2749 Renew(converted_start, *lenp + 1, U8);
2750
2751 return converted_start;
2752 }
2753
2754 /*
2755 =for apidoc bytes_to_utf8
2756
2757 Converts a string C<s> of length C<*lenp> bytes from the native encoding into
2758 UTF-8.
2759 Returns a pointer to the newly-created string, and sets C<*lenp> to
2760 reflect the new length in bytes. The caller is responsible for arranging for
2761 the memory used by this string to get freed.
2762
2763 Upon successful return, the number of variants in the string can be computed by
2764 having saved the value of C<*lenp> before the call, and subtracting it from the
2765 after-call value of C<*lenp>.
2766
2767 A C<NUL> character will be written after the end of the string.
2768
2769 If you want to convert to UTF-8 from encodings other than
2770 the native (Latin1 or EBCDIC),
2771 see L</sv_recode_to_utf8>().
2772
2773 =cut
2774 */
2775
2776 U8*
Perl_bytes_to_utf8(pTHX_ const U8 * s,STRLEN * lenp)2777 Perl_bytes_to_utf8(pTHX_ const U8 *s, STRLEN *lenp)
2778 {
2779 const U8 * const send = s + (*lenp);
2780 U8 *d;
2781 U8 *dst;
2782
2783 PERL_ARGS_ASSERT_BYTES_TO_UTF8;
2784 PERL_UNUSED_CONTEXT;
2785
2786 /* 1 for each byte + 1 for each byte that expands to two, + trailing NUL */
2787 Newx(d, (*lenp) + variant_under_utf8_count(s, send) + 1, U8);
2788 dst = d;
2789
2790 while (s < send) {
2791 append_utf8_from_native_byte(*s, &d);
2792 s++;
2793 }
2794
2795 *d = '\0';
2796 *lenp = d-dst;
2797
2798 return dst;
2799 }
2800
2801 /*
2802 * Convert native UTF-16 to UTF-8. Called via the more public functions
2803 * utf16_to_utf8() for big-endian and utf16_to_utf8_reversed() for
2804 * little-endian,
2805 *
2806 * 'p' is the UTF-16 input string, passed as a pointer to U8.
2807 * 'bytelen' is its length (must be even)
2808 * 'd' is the pointer to the destination buffer. The caller must ensure that
2809 * the space is large enough. The maximum expansion factor is 2 times
2810 * 'bytelen'. 1.5 if never going to run on an EBCDIC box.
2811 * '*newlen' will contain the number of bytes this function filled of 'd'.
2812 * 'high_byte' is 0 if UTF-16BE; 1 if UTF-16LE
2813 * 'low_byte' is 1 if UTF-16BE; 0 if UTF-16LE
2814 *
2815 * The expansion factor is because UTF-16 requires 2 bytes for every code point
2816 * below 0x10000; otherwise 4 bytes. UTF-8 requires 1-3 bytes for every code
2817 * point below 0x1000; otherwise 4 bytes. UTF-EBCDIC requires 1-4 bytes for
2818 * every code point below 0x1000; otherwise 4-5 bytes.
2819 *
2820 * The worst case is where every code point is below U+10000, hence requiring 2
2821 * UTF-16 bytes, but is U+0800 or higher on ASCII platforms, requiring 3 UTF-8
2822 * bytes; or >= U+4000 on EBCDIC requiring 4 UTF-8 bytes.
2823 *
2824 * Do not use in-place. */
2825
2826 U8*
Perl_utf16_to_utf8_base(pTHX_ U8 * p,U8 * d,Size_t bytelen,Size_t * newlen,const bool high_byte,const bool low_byte)2827 Perl_utf16_to_utf8_base(pTHX_ U8* p, U8* d, Size_t bytelen, Size_t *newlen,
2828 const bool high_byte, /* Which of next two bytes is
2829 high order */
2830 const bool low_byte)
2831 {
2832 U8* pend;
2833 U8* dstart = d;
2834
2835 PERL_ARGS_ASSERT_UTF16_TO_UTF8_BASE;
2836
2837 if (bytelen & 1)
2838 Perl_croak(aTHX_ "panic: utf16_to_utf8%s: odd bytelen %" UVuf,
2839 ((high_byte == 0) ? "" : "_reversed"), (UV)bytelen);
2840 pend = p + bytelen;
2841
2842 while (p < pend) {
2843
2844 /* Next 16 bits is what we want. (The bool is cast to U8 because on
2845 * platforms where a bool is implemented as a signed char, a compiler
2846 * warning may be generated) */
2847 U32 uv = (p[(U8) high_byte] << 8) + p[(U8) low_byte];
2848 p += 2;
2849
2850 /* If it's a surrogate, we find the uv that the surrogate pair encodes.
2851 * */
2852 if (UNLIKELY(UNICODE_IS_SURROGATE(uv))) {
2853
2854 #define FIRST_HIGH_SURROGATE UNICODE_SURROGATE_FIRST
2855 #define LAST_HIGH_SURROGATE 0xDBFF
2856 #define FIRST_LOW_SURROGATE 0xDC00
2857 #define LAST_LOW_SURROGATE UNICODE_SURROGATE_LAST
2858 #define FIRST_IN_PLANE1 0x10000
2859
2860 if (UNLIKELY(p >= pend) || UNLIKELY(uv > LAST_HIGH_SURROGATE)) {
2861 Perl_croak(aTHX_ "Malformed UTF-16 surrogate");
2862 }
2863 else {
2864 U32 low_surrogate = (p[(U8) high_byte] << 8) + p[(U8) low_byte];
2865 if (UNLIKELY(! inRANGE(low_surrogate, FIRST_LOW_SURROGATE,
2866 LAST_LOW_SURROGATE)))
2867 {
2868 Perl_croak(aTHX_ "Malformed UTF-16 surrogate");
2869 }
2870
2871 p += 2;
2872
2873 /* Here uv is the high surrogate. Combine with low surrogate
2874 * just computed to form the actual U32 code point.
2875 *
2876 * From https://unicode.org/faq/utf_bom.html#utf16-4 */
2877 uv = FIRST_IN_PLANE1 + (uv << 10) - (FIRST_HIGH_SURROGATE << 10)
2878 + low_surrogate - FIRST_LOW_SURROGATE;
2879 }
2880 }
2881
2882 /* Here, 'uv' is the real U32 we want to find the UTF-8 of */
2883 d = uvchr_to_utf8(d, uv);
2884 }
2885
2886 *newlen = d - dstart;
2887 return d;
2888 }
2889
2890 U8*
Perl_utf16_to_utf8(pTHX_ U8 * p,U8 * d,Size_t bytelen,Size_t * newlen)2891 Perl_utf16_to_utf8(pTHX_ U8* p, U8* d, Size_t bytelen, Size_t *newlen)
2892 {
2893 PERL_ARGS_ASSERT_UTF16_TO_UTF8;
2894
2895 return utf16_to_utf8(p, d, bytelen, newlen);
2896 }
2897
2898 U8*
Perl_utf16_to_utf8_reversed(pTHX_ U8 * p,U8 * d,Size_t bytelen,Size_t * newlen)2899 Perl_utf16_to_utf8_reversed(pTHX_ U8* p, U8* d, Size_t bytelen, Size_t *newlen)
2900 {
2901 PERL_ARGS_ASSERT_UTF16_TO_UTF8_REVERSED;
2902
2903 return utf16_to_utf8_reversed(p, d, bytelen, newlen);
2904 }
2905
2906 /*
2907 * Convert UTF-8 to native UTF-16. Called via the macros utf8_to_utf16() for
2908 * big-endian and utf8_to_utf16_reversed() for little-endian,
2909 *
2910 * 's' is the UTF-8 input string, passed as a pointer to U8.
2911 * 'bytelen' is its length
2912 * 'd' is the pointer to the destination buffer, currently passed as U8 *. The
2913 * caller must ensure that the space is large enough. The maximum
2914 * expansion factor is 2 times 'bytelen'. This happens when the input is
2915 * entirely single-byte ASCII, expanding to two-byte UTF-16.
2916 * '*newlen' will contain the number of bytes this function filled of 'd'.
2917 * 'high_byte' is 0 if UTF-16BE; 1 if UTF-16LE
2918 * 'low_byte' is 1 if UTF-16BE; 0 if UTF-16LE
2919 *
2920 * Do not use in-place. */
2921 U8*
Perl_utf8_to_utf16_base(pTHX_ U8 * s,U8 * d,Size_t bytelen,Size_t * newlen,const bool high_byte,const bool low_byte)2922 Perl_utf8_to_utf16_base(pTHX_ U8* s, U8* d, Size_t bytelen, Size_t *newlen,
2923 const bool high_byte, /* Which of next two bytes
2924 is high order */
2925 const bool low_byte)
2926 {
2927 U8* send;
2928 U8* dstart = d;
2929
2930 PERL_ARGS_ASSERT_UTF8_TO_UTF16_BASE;
2931
2932 send = s + bytelen;
2933
2934 while (s < send) {
2935 STRLEN retlen;
2936 UV uv = utf8n_to_uvchr(s, send - s, &retlen,
2937 /* No surrogates nor above-Unicode */
2938 UTF8_DISALLOW_ILLEGAL_C9_INTERCHANGE);
2939
2940 /* The modern method is to keep going with malformed input,
2941 * substituting the REPLACEMENT CHARACTER */
2942 if (UNLIKELY(uv == 0 && *s != '\0')) {
2943 uv = UNICODE_REPLACEMENT;
2944 }
2945
2946 if (uv >= FIRST_IN_PLANE1) { /* Requires a surrogate pair */
2947
2948 /* From https://unicode.org/faq/utf_bom.html#utf16-4 */
2949 U32 high_surrogate = (uv >> 10) - (FIRST_IN_PLANE1 >> 10)
2950 + FIRST_HIGH_SURROGATE;
2951
2952 /* (The bool is cast to U8 because on platforms where a bool is
2953 * implemented as a signed char, a compiler warning may be
2954 * generated) */
2955 d[(U8) high_byte] = high_surrogate >> 8;
2956 d[(U8) low_byte] = high_surrogate & nBIT_MASK(8);
2957 d += 2;
2958
2959 /* The low surrogate is the lower 10 bits plus the offset */
2960 uv &= nBIT_MASK(10);
2961 uv += FIRST_LOW_SURROGATE;
2962
2963 /* Drop down to output the low surrogate like it were a
2964 * non-surrogate */
2965 }
2966
2967 d[(U8) high_byte] = uv >> 8;
2968 d[(U8) low_byte] = uv & nBIT_MASK(8);
2969 d += 2;
2970
2971 s += retlen;
2972 }
2973
2974 *newlen = d - dstart;
2975 return d;
2976 }
2977
2978 bool
Perl__is_uni_FOO(pTHX_ const U8 classnum,const UV c)2979 Perl__is_uni_FOO(pTHX_ const U8 classnum, const UV c)
2980 {
2981 return _invlist_contains_cp(PL_XPosix_ptrs[classnum], c);
2982 }
2983
2984 bool
Perl__is_uni_perl_idcont(pTHX_ UV c)2985 Perl__is_uni_perl_idcont(pTHX_ UV c)
2986 {
2987 return _invlist_contains_cp(PL_utf8_perl_idcont, c);
2988 }
2989
2990 bool
Perl__is_uni_perl_idstart(pTHX_ UV c)2991 Perl__is_uni_perl_idstart(pTHX_ UV c)
2992 {
2993 return _invlist_contains_cp(PL_utf8_perl_idstart, c);
2994 }
2995
2996 UV
Perl__to_upper_title_latin1(pTHX_ const U8 c,U8 * p,STRLEN * lenp,const char S_or_s)2997 Perl__to_upper_title_latin1(pTHX_ const U8 c, U8* p, STRLEN *lenp,
2998 const char S_or_s)
2999 {
3000 /* We have the latin1-range values compiled into the core, so just use
3001 * those, converting the result to UTF-8. The only difference between upper
3002 * and title case in this range is that LATIN_SMALL_LETTER_SHARP_S is
3003 * either "SS" or "Ss". Which one to use is passed into the routine in
3004 * 'S_or_s' to avoid a test */
3005
3006 UV converted = toUPPER_LATIN1_MOD(c);
3007
3008 PERL_ARGS_ASSERT__TO_UPPER_TITLE_LATIN1;
3009
3010 assert(S_or_s == 'S' || S_or_s == 's');
3011
3012 if (UVCHR_IS_INVARIANT(converted)) { /* No difference between the two for
3013 characters in this range */
3014 *p = (U8) converted;
3015 *lenp = 1;
3016 return converted;
3017 }
3018
3019 /* toUPPER_LATIN1_MOD gives the correct results except for three outliers,
3020 * which it maps to one of them, so as to only have to have one check for
3021 * it in the main case */
3022 if (UNLIKELY(converted == LATIN_SMALL_LETTER_Y_WITH_DIAERESIS)) {
3023 switch (c) {
3024 case LATIN_SMALL_LETTER_Y_WITH_DIAERESIS:
3025 converted = LATIN_CAPITAL_LETTER_Y_WITH_DIAERESIS;
3026 break;
3027 case MICRO_SIGN:
3028 converted = GREEK_CAPITAL_LETTER_MU;
3029 break;
3030 #if UNICODE_MAJOR_VERSION > 2 \
3031 || (UNICODE_MAJOR_VERSION == 2 && UNICODE_DOT_VERSION >= 1 \
3032 && UNICODE_DOT_DOT_VERSION >= 8)
3033 case LATIN_SMALL_LETTER_SHARP_S:
3034 *(p)++ = 'S';
3035 *p = S_or_s;
3036 *lenp = 2;
3037 return 'S';
3038 #endif
3039 default:
3040 Perl_croak(aTHX_ "panic: to_upper_title_latin1 did not expect"
3041 " '%c' to map to '%c'",
3042 c, LATIN_SMALL_LETTER_Y_WITH_DIAERESIS);
3043 NOT_REACHED; /* NOTREACHED */
3044 }
3045 }
3046
3047 *(p)++ = UTF8_TWO_BYTE_HI(converted);
3048 *p = UTF8_TWO_BYTE_LO(converted);
3049 *lenp = 2;
3050
3051 return converted;
3052 }
3053
3054 /* If compiled on an early Unicode version, there may not be auxiliary tables
3055 * */
3056 #ifndef HAS_UC_AUX_TABLES
3057 # define UC_AUX_TABLE_ptrs NULL
3058 # define UC_AUX_TABLE_lengths NULL
3059 #endif
3060 #ifndef HAS_TC_AUX_TABLES
3061 # define TC_AUX_TABLE_ptrs NULL
3062 # define TC_AUX_TABLE_lengths NULL
3063 #endif
3064 #ifndef HAS_LC_AUX_TABLES
3065 # define LC_AUX_TABLE_ptrs NULL
3066 # define LC_AUX_TABLE_lengths NULL
3067 #endif
3068 #ifndef HAS_CF_AUX_TABLES
3069 # define CF_AUX_TABLE_ptrs NULL
3070 # define CF_AUX_TABLE_lengths NULL
3071 #endif
3072
3073 /* Call the function to convert a UTF-8 encoded character to the specified case.
3074 * Note that there may be more than one character in the result.
3075 * 's' is a pointer to the first byte of the input character
3076 * 'd' will be set to the first byte of the string of changed characters. It
3077 * needs to have space for UTF8_MAXBYTES_CASE+1 bytes
3078 * 'lenp' will be set to the length in bytes of the string of changed characters
3079 *
3080 * The functions return the ordinal of the first character in the string of
3081 * 'd' */
3082 #define CALL_UPPER_CASE(uv, s, d, lenp) \
3083 _to_utf8_case(uv, s, d, lenp, PL_utf8_toupper, \
3084 Uppercase_Mapping_invmap, \
3085 UC_AUX_TABLE_ptrs, \
3086 UC_AUX_TABLE_lengths, \
3087 "uppercase")
3088 #define CALL_TITLE_CASE(uv, s, d, lenp) \
3089 _to_utf8_case(uv, s, d, lenp, PL_utf8_totitle, \
3090 Titlecase_Mapping_invmap, \
3091 TC_AUX_TABLE_ptrs, \
3092 TC_AUX_TABLE_lengths, \
3093 "titlecase")
3094 #define CALL_LOWER_CASE(uv, s, d, lenp) \
3095 _to_utf8_case(uv, s, d, lenp, PL_utf8_tolower, \
3096 Lowercase_Mapping_invmap, \
3097 LC_AUX_TABLE_ptrs, \
3098 LC_AUX_TABLE_lengths, \
3099 "lowercase")
3100
3101
3102 /* This additionally has the input parameter 'specials', which if non-zero will
3103 * cause this to use the specials hash for folding (meaning get full case
3104 * folding); otherwise, when zero, this implies a simple case fold */
3105 #define CALL_FOLD_CASE(uv, s, d, lenp, specials) \
3106 (specials) \
3107 ? _to_utf8_case(uv, s, d, lenp, PL_utf8_tofold, \
3108 Case_Folding_invmap, \
3109 CF_AUX_TABLE_ptrs, \
3110 CF_AUX_TABLE_lengths, \
3111 "foldcase") \
3112 : _to_utf8_case(uv, s, d, lenp, PL_utf8_tosimplefold, \
3113 Simple_Case_Folding_invmap, \
3114 NULL, NULL, \
3115 "foldcase")
3116
3117 UV
Perl_to_uni_upper(pTHX_ UV c,U8 * p,STRLEN * lenp)3118 Perl_to_uni_upper(pTHX_ UV c, U8* p, STRLEN *lenp)
3119 {
3120 /* Convert the Unicode character whose ordinal is <c> to its uppercase
3121 * version and store that in UTF-8 in <p> and its length in bytes in <lenp>.
3122 * Note that the <p> needs to be at least UTF8_MAXBYTES_CASE+1 bytes since
3123 * the changed version may be longer than the original character.
3124 *
3125 * The ordinal of the first character of the changed version is returned
3126 * (but note, as explained above, that there may be more.) */
3127
3128 PERL_ARGS_ASSERT_TO_UNI_UPPER;
3129
3130 if (c < 256) {
3131 return _to_upper_title_latin1((U8) c, p, lenp, 'S');
3132 }
3133
3134 return CALL_UPPER_CASE(c, NULL, p, lenp);
3135 }
3136
3137 UV
Perl_to_uni_title(pTHX_ UV c,U8 * p,STRLEN * lenp)3138 Perl_to_uni_title(pTHX_ UV c, U8* p, STRLEN *lenp)
3139 {
3140 PERL_ARGS_ASSERT_TO_UNI_TITLE;
3141
3142 if (c < 256) {
3143 return _to_upper_title_latin1((U8) c, p, lenp, 's');
3144 }
3145
3146 return CALL_TITLE_CASE(c, NULL, p, lenp);
3147 }
3148
3149 STATIC U8
S_to_lower_latin1(const U8 c,U8 * p,STRLEN * lenp,const char dummy)3150 S_to_lower_latin1(const U8 c, U8* p, STRLEN *lenp, const char dummy)
3151 {
3152 /* We have the latin1-range values compiled into the core, so just use
3153 * those, converting the result to UTF-8. Since the result is always just
3154 * one character, we allow <p> to be NULL */
3155
3156 U8 converted = toLOWER_LATIN1(c);
3157
3158 PERL_UNUSED_ARG(dummy);
3159
3160 if (p != NULL) {
3161 if (NATIVE_BYTE_IS_INVARIANT(converted)) {
3162 *p = converted;
3163 *lenp = 1;
3164 }
3165 else {
3166 /* Result is known to always be < 256, so can use the EIGHT_BIT
3167 * macros */
3168 *p = UTF8_EIGHT_BIT_HI(converted);
3169 *(p+1) = UTF8_EIGHT_BIT_LO(converted);
3170 *lenp = 2;
3171 }
3172 }
3173 return converted;
3174 }
3175
3176 UV
Perl_to_uni_lower(pTHX_ UV c,U8 * p,STRLEN * lenp)3177 Perl_to_uni_lower(pTHX_ UV c, U8* p, STRLEN *lenp)
3178 {
3179 PERL_ARGS_ASSERT_TO_UNI_LOWER;
3180
3181 if (c < 256) {
3182 return to_lower_latin1((U8) c, p, lenp, 0 /* 0 is a dummy arg */ );
3183 }
3184
3185 return CALL_LOWER_CASE(c, NULL, p, lenp);
3186 }
3187
3188 UV
Perl__to_fold_latin1(const U8 c,U8 * p,STRLEN * lenp,const unsigned int flags)3189 Perl__to_fold_latin1(const U8 c, U8* p, STRLEN *lenp, const unsigned int flags)
3190 {
3191 /* Corresponds to to_lower_latin1(); <flags> bits meanings:
3192 * FOLD_FLAGS_NOMIX_ASCII iff non-ASCII to ASCII folds are prohibited
3193 * FOLD_FLAGS_FULL iff full folding is to be used;
3194 *
3195 * Not to be used for locale folds
3196 */
3197
3198 UV converted;
3199
3200 PERL_ARGS_ASSERT__TO_FOLD_LATIN1;
3201
3202 assert (! (flags & FOLD_FLAGS_LOCALE));
3203
3204 if (UNLIKELY(c == MICRO_SIGN)) {
3205 converted = GREEK_SMALL_LETTER_MU;
3206 }
3207 #if UNICODE_MAJOR_VERSION > 3 /* no multifolds in early Unicode */ \
3208 || (UNICODE_MAJOR_VERSION == 3 && ( UNICODE_DOT_VERSION > 0) \
3209 || UNICODE_DOT_DOT_VERSION > 0)
3210 else if ( (flags & FOLD_FLAGS_FULL)
3211 && UNLIKELY(c == LATIN_SMALL_LETTER_SHARP_S))
3212 {
3213 /* If can't cross 127/128 boundary, can't return "ss"; instead return
3214 * two U+017F characters, as fc("\df") should eq fc("\x{17f}\x{17f}")
3215 * under those circumstances. */
3216 if (flags & FOLD_FLAGS_NOMIX_ASCII) {
3217 *lenp = 2 * STRLENs(LATIN_SMALL_LETTER_LONG_S_UTF8);
3218 Copy(LATIN_SMALL_LETTER_LONG_S_UTF8 LATIN_SMALL_LETTER_LONG_S_UTF8,
3219 p, *lenp, U8);
3220 return LATIN_SMALL_LETTER_LONG_S;
3221 }
3222 else {
3223 *(p)++ = 's';
3224 *p = 's';
3225 *lenp = 2;
3226 return 's';
3227 }
3228 }
3229 #endif
3230 else { /* In this range the fold of all other characters is their lower
3231 case */
3232 converted = toLOWER_LATIN1(c);
3233 }
3234
3235 if (UVCHR_IS_INVARIANT(converted)) {
3236 *p = (U8) converted;
3237 *lenp = 1;
3238 }
3239 else {
3240 *(p)++ = UTF8_TWO_BYTE_HI(converted);
3241 *p = UTF8_TWO_BYTE_LO(converted);
3242 *lenp = 2;
3243 }
3244
3245 return converted;
3246 }
3247
3248 UV
Perl__to_uni_fold_flags(pTHX_ UV c,U8 * p,STRLEN * lenp,U8 flags)3249 Perl__to_uni_fold_flags(pTHX_ UV c, U8* p, STRLEN *lenp, U8 flags)
3250 {
3251
3252 /* Not currently externally documented, and subject to change
3253 * <flags> bits meanings:
3254 * FOLD_FLAGS_FULL iff full folding is to be used;
3255 * FOLD_FLAGS_LOCALE is set iff the rules from the current underlying
3256 * locale are to be used.
3257 * FOLD_FLAGS_NOMIX_ASCII iff non-ASCII to ASCII folds are prohibited
3258 */
3259
3260 PERL_ARGS_ASSERT__TO_UNI_FOLD_FLAGS;
3261
3262 if (flags & FOLD_FLAGS_LOCALE) {
3263 /* Treat a non-Turkic UTF-8 locale as not being in locale at all,
3264 * except for potentially warning */
3265 CHECK_AND_WARN_PROBLEMATIC_LOCALE_;
3266 if (IN_UTF8_CTYPE_LOCALE && ! IN_UTF8_TURKIC_LOCALE) {
3267 flags &= ~FOLD_FLAGS_LOCALE;
3268 }
3269 else {
3270 goto needs_full_generality;
3271 }
3272 }
3273
3274 if (c < 256) {
3275 return _to_fold_latin1((U8) c, p, lenp,
3276 flags & (FOLD_FLAGS_FULL | FOLD_FLAGS_NOMIX_ASCII));
3277 }
3278
3279 /* Here, above 255. If no special needs, just use the macro */
3280 if ( ! (flags & (FOLD_FLAGS_LOCALE|FOLD_FLAGS_NOMIX_ASCII))) {
3281 return CALL_FOLD_CASE(c, NULL, p, lenp, flags & FOLD_FLAGS_FULL);
3282 }
3283 else { /* Otherwise, _toFOLD_utf8_flags has the intelligence to deal with
3284 the special flags. */
3285 U8 utf8_c[UTF8_MAXBYTES + 1];
3286
3287 needs_full_generality:
3288 uvchr_to_utf8(utf8_c, c);
3289 return _toFOLD_utf8_flags(utf8_c, utf8_c + C_ARRAY_LENGTH(utf8_c),
3290 p, lenp, flags);
3291 }
3292 }
3293
3294 PERL_STATIC_INLINE bool
S_is_utf8_common(pTHX_ const U8 * const p,const U8 * const e,SV * const invlist)3295 S_is_utf8_common(pTHX_ const U8 *const p, const U8 * const e,
3296 SV* const invlist)
3297 {
3298 /* returns a boolean giving whether or not the UTF8-encoded character that
3299 * starts at <p>, and extending no further than <e - 1> is in the inversion
3300 * list <invlist>. */
3301
3302 UV cp = utf8n_to_uvchr(p, e - p, NULL, 0);
3303
3304 PERL_ARGS_ASSERT_IS_UTF8_COMMON;
3305
3306 if (cp == 0 && (p >= e || *p != '\0')) {
3307 _force_out_malformed_utf8_message(p, e, 0, 1);
3308 NOT_REACHED; /* NOTREACHED */
3309 }
3310
3311 assert(invlist);
3312 return _invlist_contains_cp(invlist, cp);
3313 }
3314
3315 #if 0 /* Not currently used, but may be needed in the future */
PERLVAR(I,seen_deprecated_macro,HV *)3316 PERLVAR(I, seen_deprecated_macro, HV *)
3317
3318 STATIC void
3319 S_warn_on_first_deprecated_use(pTHX_ U32 category,
3320 const char * const name,
3321 const char * const alternative,
3322 const bool use_locale,
3323 const char * const file,
3324 const unsigned line)
3325 {
3326 const char * key;
3327
3328 PERL_ARGS_ASSERT_WARN_ON_FIRST_DEPRECATED_USE;
3329
3330 if (ckWARN_d(category)) {
3331
3332 key = Perl_form(aTHX_ "%s;%d;%s;%d", name, use_locale, file, line);
3333 if (! hv_fetch(PL_seen_deprecated_macro, key, strlen(key), 0)) {
3334 if (! PL_seen_deprecated_macro) {
3335 PL_seen_deprecated_macro = newHV();
3336 }
3337 if (! hv_store(PL_seen_deprecated_macro, key,
3338 strlen(key), &PL_sv_undef, 0))
3339 {
3340 Perl_croak(aTHX_ "panic: hv_store() unexpectedly failed");
3341 }
3342
3343 if (instr(file, "mathoms.c")) {
3344 Perl_warner(aTHX_ category,
3345 "In %s, line %d, starting in Perl v5.32, %s()"
3346 " will be removed. Avoid this message by"
3347 " converting to use %s().\n",
3348 file, line, name, alternative);
3349 }
3350 else {
3351 Perl_warner(aTHX_ category,
3352 "In %s, line %d, starting in Perl v5.32, %s() will"
3353 " require an additional parameter. Avoid this"
3354 " message by converting to use %s().\n",
3355 file, line, name, alternative);
3356 }
3357 }
3358 }
3359 }
3360 #endif
3361
3362 bool
Perl__is_utf8_FOO(pTHX_ const U8 classnum,const U8 * p,const U8 * const e)3363 Perl__is_utf8_FOO(pTHX_ const U8 classnum, const U8 *p, const U8 * const e)
3364 {
3365 PERL_ARGS_ASSERT__IS_UTF8_FOO;
3366
3367 return is_utf8_common(p, e, PL_XPosix_ptrs[classnum]);
3368 }
3369
3370 bool
Perl__is_utf8_perl_idstart(pTHX_ const U8 * p,const U8 * const e)3371 Perl__is_utf8_perl_idstart(pTHX_ const U8 *p, const U8 * const e)
3372 {
3373 PERL_ARGS_ASSERT__IS_UTF8_PERL_IDSTART;
3374
3375 return is_utf8_common(p, e, PL_utf8_perl_idstart);
3376 }
3377
3378 bool
Perl__is_utf8_perl_idcont(pTHX_ const U8 * p,const U8 * const e)3379 Perl__is_utf8_perl_idcont(pTHX_ const U8 *p, const U8 * const e)
3380 {
3381 PERL_ARGS_ASSERT__IS_UTF8_PERL_IDCONT;
3382
3383 return is_utf8_common(p, e, PL_utf8_perl_idcont);
3384 }
3385
3386 STATIC UV
S_to_case_cp_list(pTHX_ const UV original,const U32 ** const remaining_list,Size_t * remaining_count,SV * invlist,const I32 * const invmap,const U32 * const * const aux_tables,const U8 * const aux_table_lengths,const char * const normal)3387 S_to_case_cp_list(pTHX_
3388 const UV original,
3389 const U32 ** const remaining_list,
3390 Size_t * remaining_count,
3391 SV *invlist, const I32 * const invmap,
3392 const U32 * const * const aux_tables,
3393 const U8 * const aux_table_lengths,
3394 const char * const normal)
3395 {
3396 SSize_t index;
3397 I32 base;
3398
3399 /* Calculate the changed case of code point 'original'. The first code
3400 * point of the changed case is returned.
3401 *
3402 * If 'remaining_count' is not NULL, *remaining_count will be set to how
3403 * many *other* code points are in the changed case. If non-zero and
3404 * 'remaining_list' is also not NULL, *remaining_list will be set to point
3405 * to a non-modifiable array containing the second and potentially third
3406 * code points in the changed case. (Unicode guarantees a maximum of 3.)
3407 * Note that this means that *remaining_list is undefined unless there are
3408 * multiple code points, and the caller has chosen to find out how many by
3409 * making 'remaining_count' not NULL.
3410 *
3411 * 'normal' is a string to use to name the new case in any generated
3412 * messages, as a fallback if the operation being used is not available.
3413 *
3414 * The casing to use is given by the data structures in the remaining
3415 * arguments.
3416 */
3417
3418 PERL_ARGS_ASSERT_TO_CASE_CP_LIST;
3419
3420 /* 'index' is guaranteed to be non-negative, as this is an inversion map
3421 * that covers all possible inputs. See [perl #133365] */
3422 index = _invlist_search(invlist, original);
3423 base = invmap[index];
3424
3425 /* Most likely, the case change will contain just a single code point */
3426 if (remaining_count) {
3427 *remaining_count = 0;
3428 }
3429
3430 if (LIKELY(base == 0)) { /* 0 => original was unchanged by casing */
3431
3432 /* At this bottom level routine is where we warn about illegal code
3433 * points */
3434 if (isUNICODE_POSSIBLY_PROBLEMATIC(original)) {
3435 if (UNLIKELY(UNICODE_IS_SURROGATE(original))) {
3436 if (ckWARN_d(WARN_SURROGATE)) {
3437 const char* desc = (PL_op) ? OP_DESC(PL_op) : normal;
3438 Perl_warner(aTHX_ packWARN(WARN_SURROGATE),
3439 "Operation \"%s\" returns its argument for"
3440 " UTF-16 surrogate U+%04" UVXf, desc, original);
3441 }
3442 }
3443 else if (UNLIKELY(UNICODE_IS_SUPER(original))) {
3444 if (UNLIKELY(original > MAX_LEGAL_CP)) {
3445 Perl_croak(aTHX_ "%s", form_cp_too_large_msg(16, NULL, 0, original));
3446 }
3447 if (ckWARN_d(WARN_NON_UNICODE)) {
3448 const char* desc = (PL_op) ? OP_DESC(PL_op) : normal;
3449 Perl_warner(aTHX_ packWARN(WARN_NON_UNICODE),
3450 "Operation \"%s\" returns its argument for"
3451 " non-Unicode code point 0x%04" UVXf, desc, original);
3452 }
3453 }
3454
3455 /* Note that non-characters are perfectly legal, so no warning
3456 * should be given. */
3457 }
3458
3459 return original;
3460 }
3461
3462 if (LIKELY(base > 0)) { /* means original mapped to a single code point,
3463 different from itself */
3464 return base + original - invlist_array(invlist)[index];
3465 }
3466
3467 /* Here 'base' is negative. That means the mapping is 1-to-many, and
3468 * requires an auxiliary table look up. abs(base) gives the index into a
3469 * list of such tables which points to the proper aux table. And a
3470 * parallel list gives the length of each corresponding aux table. Skip
3471 * the first entry in the *remaining returns, as it is returned by the
3472 * function. */
3473 base = -base;
3474 if (remaining_count) {
3475 *remaining_count = (Size_t) (aux_table_lengths[base] - 1);
3476
3477 if (remaining_list) {
3478 *remaining_list = aux_tables[base] + 1;
3479 }
3480 }
3481
3482 return (UV) aux_tables[base][0];
3483 }
3484
3485 STATIC UV
S__to_utf8_case(pTHX_ const UV original,const U8 * p,U8 * ustrp,STRLEN * lenp,SV * invlist,const I32 * const invmap,const U32 * const * const aux_tables,const U8 * const aux_table_lengths,const char * const normal)3486 S__to_utf8_case(pTHX_ const UV original, const U8 *p,
3487 U8* ustrp, STRLEN *lenp,
3488 SV *invlist, const I32 * const invmap,
3489 const U32 * const * const aux_tables,
3490 const U8 * const aux_table_lengths,
3491 const char * const normal)
3492 {
3493 /* Change the case of code point 'original'. If 'p' is non-NULL, it points to
3494 * the beginning of the (assumed to be valid) UTF-8 representation of
3495 * 'original'. 'normal' is a string to use to name the new case in any
3496 * generated messages, as a fallback if the operation being used is not
3497 * available. The new case is given by the data structures in the
3498 * remaining arguments.
3499 *
3500 * On return 'ustrp' points to '*lenp' UTF-8 encoded bytes representing the
3501 * entire changed case string, and the return value is the first code point
3502 * in that string
3503 *
3504 * Note that the <ustrp> needs to be at least UTF8_MAXBYTES_CASE+1 bytes
3505 * since the changed version may be longer than the original character. */
3506
3507 const U32 * remaining_list;
3508 Size_t remaining_count;
3509 UV first = to_case_cp_list(original,
3510 &remaining_list, &remaining_count,
3511 invlist, invmap,
3512 aux_tables, aux_table_lengths,
3513 normal);
3514
3515 PERL_ARGS_ASSERT__TO_UTF8_CASE;
3516
3517 /* If the code point maps to itself and we already have its representation,
3518 * copy it instead of recalculating */
3519 if (original == first && p) {
3520 *lenp = UTF8SKIP(p);
3521
3522 if (p != ustrp) { /* Don't copy onto itself */
3523 Copy(p, ustrp, *lenp, U8);
3524 }
3525 }
3526 else {
3527 U8 * d = ustrp;
3528 Size_t i;
3529
3530 d = uvchr_to_utf8(d, first);
3531
3532 for (i = 0; i < remaining_count; i++) {
3533 d = uvchr_to_utf8(d, remaining_list[i]);
3534 }
3535
3536 *d = '\0';
3537 *lenp = d - ustrp;
3538 }
3539
3540 return first;
3541 }
3542
3543 Size_t
Perl__inverse_folds(pTHX_ const UV cp,U32 * first_folds_to,const U32 ** remaining_folds_to)3544 Perl__inverse_folds(pTHX_ const UV cp, U32 * first_folds_to,
3545 const U32 ** remaining_folds_to)
3546 {
3547 /* Returns the count of the number of code points that fold to the input
3548 * 'cp' (besides itself).
3549 *
3550 * If the return is 0, there is nothing else that folds to it, and
3551 * '*first_folds_to' is set to 0, and '*remaining_folds_to' is set to NULL.
3552 *
3553 * If the return is 1, '*first_folds_to' is set to the single code point,
3554 * and '*remaining_folds_to' is set to NULL.
3555 *
3556 * Otherwise, '*first_folds_to' is set to a code point, and
3557 * '*remaining_fold_to' is set to an array that contains the others. The
3558 * length of this array is the returned count minus 1.
3559 *
3560 * The reason for this convolution is to avoid having to deal with
3561 * allocating and freeing memory. The lists are already constructed, so
3562 * the return can point to them, but single code points aren't, so would
3563 * need to be constructed if we didn't employ something like this API
3564 *
3565 * The code points returned by this function are all legal Unicode, which
3566 * occupy at most 21 bits, and so a U32 is sufficient, and the lists are
3567 * constructed with this size (to save space and memory), and we return
3568 * pointers, so they must be this size */
3569
3570 /* 'index' is guaranteed to be non-negative, as this is an inversion map
3571 * that covers all possible inputs. See [perl #133365] */
3572 SSize_t index = _invlist_search(PL_utf8_foldclosures, cp);
3573 I32 base = _Perl_IVCF_invmap[index];
3574
3575 PERL_ARGS_ASSERT__INVERSE_FOLDS;
3576
3577 if (base == 0) { /* No fold */
3578 *first_folds_to = 0;
3579 *remaining_folds_to = NULL;
3580 return 0;
3581 }
3582
3583 #ifndef HAS_IVCF_AUX_TABLES /* This Unicode version only has 1-1 folds */
3584
3585 assert(base > 0);
3586
3587 #else
3588
3589 if (UNLIKELY(base < 0)) { /* Folds to more than one character */
3590
3591 /* The data structure is set up so that the absolute value of 'base' is
3592 * an index into a table of pointers to arrays, with the array
3593 * corresponding to the index being the list of code points that fold
3594 * to 'cp', and the parallel array containing the length of the list
3595 * array */
3596 *first_folds_to = IVCF_AUX_TABLE_ptrs[-base][0];
3597 *remaining_folds_to = IVCF_AUX_TABLE_ptrs[-base] + 1;
3598 /* +1 excludes first_folds_to */
3599 return IVCF_AUX_TABLE_lengths[-base];
3600 }
3601
3602 #endif
3603
3604 /* Only the single code point. This works like 'fc(G) = G - A + a' */
3605 *first_folds_to = (U32) (base + cp
3606 - invlist_array(PL_utf8_foldclosures)[index]);
3607 *remaining_folds_to = NULL;
3608 return 1;
3609 }
3610
3611 STATIC UV
S_check_locale_boundary_crossing(pTHX_ const U8 * const p,const UV result,U8 * const ustrp,STRLEN * lenp)3612 S_check_locale_boundary_crossing(pTHX_ const U8* const p, const UV result,
3613 U8* const ustrp, STRLEN *lenp)
3614 {
3615 /* This is called when changing the case of a UTF-8-encoded character above
3616 * the Latin1 range, and the operation is in a non-UTF-8 locale. If the
3617 * result contains a character that crosses the 255/256 boundary, disallow
3618 * the change, and return the original code point. See L<perlfunc/lc> for
3619 * why;
3620 *
3621 * p points to the original string whose case was changed; assumed
3622 * by this routine to be well-formed
3623 * result the code point of the first character in the changed-case string
3624 * ustrp points to the changed-case string (<result> represents its
3625 * first char)
3626 * lenp points to the length of <ustrp> */
3627
3628 UV original; /* To store the first code point of <p> */
3629
3630 PERL_ARGS_ASSERT_CHECK_LOCALE_BOUNDARY_CROSSING;
3631
3632 assert(UTF8_IS_ABOVE_LATIN1(*p));
3633
3634 /* We know immediately if the first character in the string crosses the
3635 * boundary, so can skip testing */
3636 if (result > 255) {
3637
3638 /* Look at every character in the result; if any cross the
3639 * boundary, the whole thing is disallowed */
3640 U8* s = ustrp + UTF8SKIP(ustrp);
3641 U8* e = ustrp + *lenp;
3642 while (s < e) {
3643 if (! UTF8_IS_ABOVE_LATIN1(*s)) {
3644 goto bad_crossing;
3645 }
3646 s += UTF8SKIP(s);
3647 }
3648
3649 /* Here, no characters crossed, result is ok as-is, but we warn. */
3650 _CHECK_AND_OUTPUT_WIDE_LOCALE_UTF8_MSG(p, p + UTF8SKIP(p));
3651 return result;
3652 }
3653
3654 bad_crossing:
3655
3656 /* Failed, have to return the original */
3657 original = valid_utf8_to_uvchr(p, lenp);
3658
3659 /* diag_listed_as: Can't do %s("%s") on non-UTF-8 locale; resolved to "%s". */
3660 Perl_ck_warner(aTHX_ packWARN(WARN_LOCALE),
3661 "Can't do %s(\"\\x{%" UVXf "}\") on non-UTF-8"
3662 " locale; resolved to \"\\x{%" UVXf "}\".",
3663 OP_DESC(PL_op),
3664 original,
3665 original);
3666 Copy(p, ustrp, *lenp, char);
3667 return original;
3668 }
3669
3670 STATIC UV
S_turkic_fc(pTHX_ const U8 * const p,const U8 * const e,U8 * ustrp,STRLEN * lenp)3671 S_turkic_fc(pTHX_ const U8 * const p, const U8 * const e,
3672 U8 * ustrp, STRLEN *lenp)
3673 {
3674 /* Returns 0 if the foldcase of the input UTF-8 encoded sequence from
3675 * p0..e-1 according to Turkic rules is the same as for non-Turkic.
3676 * Otherwise, it returns the first code point of the Turkic foldcased
3677 * sequence, and the entire sequence will be stored in *ustrp. ustrp will
3678 * contain *lenp bytes
3679 *
3680 * Turkic differs only from non-Turkic in that 'i' and LATIN CAPITAL LETTER
3681 * I WITH DOT ABOVE form a case pair, as do 'I' and LATIN SMALL LETTER
3682 * DOTLESS I */
3683
3684 PERL_ARGS_ASSERT_TURKIC_FC;
3685 assert(e > p);
3686
3687 if (UNLIKELY(*p == 'I')) {
3688 *lenp = 2;
3689 ustrp[0] = UTF8_TWO_BYTE_HI(LATIN_SMALL_LETTER_DOTLESS_I);
3690 ustrp[1] = UTF8_TWO_BYTE_LO(LATIN_SMALL_LETTER_DOTLESS_I);
3691 return LATIN_SMALL_LETTER_DOTLESS_I;
3692 }
3693
3694 if (UNLIKELY(memBEGINs(p, e - p,
3695 LATIN_CAPITAL_LETTER_I_WITH_DOT_ABOVE_UTF8)))
3696 {
3697 *lenp = 1;
3698 *ustrp = 'i';
3699 return 'i';
3700 }
3701
3702 return 0;
3703 }
3704
3705 STATIC UV
S_turkic_lc(pTHX_ const U8 * const p0,const U8 * const e,U8 * ustrp,STRLEN * lenp)3706 S_turkic_lc(pTHX_ const U8 * const p0, const U8 * const e,
3707 U8 * ustrp, STRLEN *lenp)
3708 {
3709 /* Returns 0 if the lowercase of the input UTF-8 encoded sequence from
3710 * p0..e-1 according to Turkic rules is the same as for non-Turkic.
3711 * Otherwise, it returns the first code point of the Turkic lowercased
3712 * sequence, and the entire sequence will be stored in *ustrp. ustrp will
3713 * contain *lenp bytes */
3714
3715 PERL_ARGS_ASSERT_TURKIC_LC;
3716 assert(e > p0);
3717
3718 /* A 'I' requires context as to what to do */
3719 if (UNLIKELY(*p0 == 'I')) {
3720 const U8 * p = p0 + 1;
3721
3722 /* According to the Unicode SpecialCasing.txt file, a capital 'I'
3723 * modified by a dot above lowercases to 'i' even in turkic locales. */
3724 while (p < e) {
3725 UV cp;
3726
3727 if (memBEGINs(p, e - p, COMBINING_DOT_ABOVE_UTF8)) {
3728 ustrp[0] = 'i';
3729 *lenp = 1;
3730 return 'i';
3731 }
3732
3733 /* For the dot above to modify the 'I', it must be part of a
3734 * combining sequence immediately following the 'I', and no other
3735 * modifier with a ccc of 230 may intervene */
3736 cp = utf8_to_uvchr_buf(p, e, NULL);
3737 if (! _invlist_contains_cp(PL_CCC_non0_non230, cp)) {
3738 break;
3739 }
3740
3741 /* Here the combining sequence continues */
3742 p += UTF8SKIP(p);
3743 }
3744 }
3745
3746 /* In all other cases the lc is the same as the fold */
3747 return turkic_fc(p0, e, ustrp, lenp);
3748 }
3749
3750 STATIC UV
S_turkic_uc(pTHX_ const U8 * const p,const U8 * const e,U8 * ustrp,STRLEN * lenp)3751 S_turkic_uc(pTHX_ const U8 * const p, const U8 * const e,
3752 U8 * ustrp, STRLEN *lenp)
3753 {
3754 /* Returns 0 if the upper or title-case of the input UTF-8 encoded sequence
3755 * from p0..e-1 according to Turkic rules is the same as for non-Turkic.
3756 * Otherwise, it returns the first code point of the Turkic upper or
3757 * title-cased sequence, and the entire sequence will be stored in *ustrp.
3758 * ustrp will contain *lenp bytes
3759 *
3760 * Turkic differs only from non-Turkic in that 'i' and LATIN CAPITAL LETTER
3761 * I WITH DOT ABOVE form a case pair, as do 'I' and LATIN SMALL LETTER
3762 * DOTLESS I */
3763
3764 PERL_ARGS_ASSERT_TURKIC_UC;
3765 assert(e > p);
3766
3767 if (*p == 'i') {
3768 *lenp = 2;
3769 ustrp[0] = UTF8_TWO_BYTE_HI(LATIN_CAPITAL_LETTER_I_WITH_DOT_ABOVE);
3770 ustrp[1] = UTF8_TWO_BYTE_LO(LATIN_CAPITAL_LETTER_I_WITH_DOT_ABOVE);
3771 return LATIN_CAPITAL_LETTER_I_WITH_DOT_ABOVE;
3772 }
3773
3774 if (memBEGINs(p, e - p, LATIN_SMALL_LETTER_DOTLESS_I_UTF8)) {
3775 *lenp = 1;
3776 *ustrp = 'I';
3777 return 'I';
3778 }
3779
3780 return 0;
3781 }
3782
3783 /* The process for changing the case is essentially the same for the four case
3784 * change types, except there are complications for folding. Otherwise the
3785 * difference is only which case to change to. To make sure that they all do
3786 * the same thing, the bodies of the functions are extracted out into the
3787 * following two macros. The functions are written with the same variable
3788 * names, and these are known and used inside these macros. It would be
3789 * better, of course, to have inline functions to do it, but since different
3790 * macros are called, depending on which case is being changed to, this is not
3791 * feasible in C (to khw's knowledge). Two macros are created so that the fold
3792 * function can start with the common start macro, then finish with its special
3793 * handling; while the other three cases can just use the common end macro.
3794 *
3795 * The algorithm is to use the proper (passed in) macro or function to change
3796 * the case for code points that are below 256. The macro is used if using
3797 * locale rules for the case change; the function if not. If the code point is
3798 * above 255, it is computed from the input UTF-8, and another macro is called
3799 * to do the conversion. If necessary, the output is converted to UTF-8. If
3800 * using a locale, we have to check that the change did not cross the 255/256
3801 * boundary, see check_locale_boundary_crossing() for further details.
3802 *
3803 * The macros are split with the correct case change for the below-256 case
3804 * stored into 'result', and in the middle of an else clause for the above-255
3805 * case. At that point in the 'else', 'result' is not the final result, but is
3806 * the input code point calculated from the UTF-8. The fold code needs to
3807 * realize all this and take it from there.
3808 *
3809 * To deal with Turkic locales, the function specified by the parameter
3810 * 'turkic' is called when appropriate.
3811 *
3812 * If you read the two macros as sequential, it's easier to understand what's
3813 * going on. */
3814 #define CASE_CHANGE_BODY_START(locale_flags, libc_change_function, L1_func, \
3815 L1_func_extra_param, turkic) \
3816 \
3817 if (flags & (locale_flags)) { \
3818 CHECK_AND_WARN_PROBLEMATIC_LOCALE_; \
3819 if (IN_UTF8_CTYPE_LOCALE) { \
3820 if (UNLIKELY(IN_UTF8_TURKIC_LOCALE)) { \
3821 UV ret = turkic(p, e, ustrp, lenp); \
3822 if (ret) return ret; \
3823 } \
3824 \
3825 /* Otherwise, treat a UTF-8 locale as not being in locale at \
3826 * all */ \
3827 flags &= ~(locale_flags); \
3828 } \
3829 } \
3830 \
3831 if (UTF8_IS_INVARIANT(*p)) { \
3832 if (flags & (locale_flags)) { \
3833 result = libc_change_function(*p); \
3834 } \
3835 else { \
3836 return L1_func(*p, ustrp, lenp, L1_func_extra_param); \
3837 } \
3838 } \
3839 else if UTF8_IS_NEXT_CHAR_DOWNGRADEABLE(p, e) { \
3840 U8 c = EIGHT_BIT_UTF8_TO_NATIVE(*p, *(p+1)); \
3841 if (flags & (locale_flags)) { \
3842 result = libc_change_function(c); \
3843 } \
3844 else { \
3845 return L1_func(c, ustrp, lenp, L1_func_extra_param); \
3846 } \
3847 } \
3848 else { /* malformed UTF-8 or ord above 255 */ \
3849 STRLEN len_result; \
3850 result = utf8n_to_uvchr(p, e - p, &len_result, UTF8_CHECK_ONLY); \
3851 if (len_result == (STRLEN) -1) { \
3852 _force_out_malformed_utf8_message(p, e, 0, 1 /* Die */ ); \
3853 }
3854
3855 #define CASE_CHANGE_BODY_END(locale_flags, change_macro) \
3856 result = change_macro(result, p, ustrp, lenp); \
3857 \
3858 if (flags & (locale_flags)) { \
3859 result = check_locale_boundary_crossing(p, result, ustrp, lenp); \
3860 } \
3861 return result; \
3862 } \
3863 \
3864 /* Here, used locale rules. Convert back to UTF-8 */ \
3865 if (UTF8_IS_INVARIANT(result)) { \
3866 *ustrp = (U8) result; \
3867 *lenp = 1; \
3868 } \
3869 else { \
3870 *ustrp = UTF8_EIGHT_BIT_HI((U8) result); \
3871 *(ustrp + 1) = UTF8_EIGHT_BIT_LO((U8) result); \
3872 *lenp = 2; \
3873 } \
3874 \
3875 return result;
3876
3877 /* Not currently externally documented, and subject to change:
3878 * <flags> is set iff the rules from the current underlying locale are to
3879 * be used. */
3880
3881 UV
Perl__to_utf8_upper_flags(pTHX_ const U8 * p,const U8 * e,U8 * ustrp,STRLEN * lenp,bool flags)3882 Perl__to_utf8_upper_flags(pTHX_ const U8 *p,
3883 const U8 *e,
3884 U8* ustrp,
3885 STRLEN *lenp,
3886 bool flags)
3887 {
3888 UV result;
3889
3890 PERL_ARGS_ASSERT__TO_UTF8_UPPER_FLAGS;
3891
3892 /* ~0 makes anything non-zero in 'flags' mean we are using locale rules */
3893 /* 2nd char of uc(U+DF) is 'S' */
3894 CASE_CHANGE_BODY_START(~0, toupper, _to_upper_title_latin1, 'S',
3895 turkic_uc);
3896 CASE_CHANGE_BODY_END (~0, CALL_UPPER_CASE);
3897 }
3898
3899 /* Not currently externally documented, and subject to change:
3900 * <flags> is set iff the rules from the current underlying locale are to be
3901 * used. Since titlecase is not defined in POSIX, for other than a
3902 * UTF-8 locale, uppercase is used instead for code points < 256.
3903 */
3904
3905 UV
Perl__to_utf8_title_flags(pTHX_ const U8 * p,const U8 * e,U8 * ustrp,STRLEN * lenp,bool flags)3906 Perl__to_utf8_title_flags(pTHX_ const U8 *p,
3907 const U8 *e,
3908 U8* ustrp,
3909 STRLEN *lenp,
3910 bool flags)
3911 {
3912 UV result;
3913
3914 PERL_ARGS_ASSERT__TO_UTF8_TITLE_FLAGS;
3915
3916 /* 2nd char of ucfirst(U+DF) is 's' */
3917 CASE_CHANGE_BODY_START(~0, toupper, _to_upper_title_latin1, 's',
3918 turkic_uc);
3919 CASE_CHANGE_BODY_END (~0, CALL_TITLE_CASE);
3920 }
3921
3922 /* Not currently externally documented, and subject to change:
3923 * <flags> is set iff the rules from the current underlying locale are to
3924 * be used.
3925 */
3926
3927 UV
Perl__to_utf8_lower_flags(pTHX_ const U8 * p,const U8 * e,U8 * ustrp,STRLEN * lenp,bool flags)3928 Perl__to_utf8_lower_flags(pTHX_ const U8 *p,
3929 const U8 *e,
3930 U8* ustrp,
3931 STRLEN *lenp,
3932 bool flags)
3933 {
3934 UV result;
3935
3936 PERL_ARGS_ASSERT__TO_UTF8_LOWER_FLAGS;
3937
3938 CASE_CHANGE_BODY_START(~0, tolower, to_lower_latin1, 0 /* 0 is dummy */,
3939 turkic_lc);
3940 CASE_CHANGE_BODY_END (~0, CALL_LOWER_CASE)
3941 }
3942
3943 /* Not currently externally documented, and subject to change,
3944 * in <flags>
3945 * bit FOLD_FLAGS_LOCALE is set iff the rules from the current underlying
3946 * locale are to be used.
3947 * bit FOLD_FLAGS_FULL is set iff full case folds are to be used;
3948 * otherwise simple folds
3949 * bit FOLD_FLAGS_NOMIX_ASCII is set iff folds of non-ASCII to ASCII are
3950 * prohibited
3951 */
3952
3953 UV
Perl__to_utf8_fold_flags(pTHX_ const U8 * p,const U8 * e,U8 * ustrp,STRLEN * lenp,U8 flags)3954 Perl__to_utf8_fold_flags(pTHX_ const U8 *p,
3955 const U8 *e,
3956 U8* ustrp,
3957 STRLEN *lenp,
3958 U8 flags)
3959 {
3960 UV result;
3961
3962 PERL_ARGS_ASSERT__TO_UTF8_FOLD_FLAGS;
3963
3964 /* These are mutually exclusive */
3965 assert (! ((flags & FOLD_FLAGS_LOCALE) && (flags & FOLD_FLAGS_NOMIX_ASCII)));
3966
3967 assert(p != ustrp); /* Otherwise overwrites */
3968
3969 CASE_CHANGE_BODY_START(FOLD_FLAGS_LOCALE, tolower, _to_fold_latin1,
3970 ((flags) & (FOLD_FLAGS_FULL | FOLD_FLAGS_NOMIX_ASCII)),
3971 turkic_fc);
3972
3973 result = CALL_FOLD_CASE(result, p, ustrp, lenp, flags & FOLD_FLAGS_FULL);
3974
3975 if (flags & FOLD_FLAGS_LOCALE) {
3976
3977 # define LONG_S_T LATIN_SMALL_LIGATURE_LONG_S_T_UTF8
3978 # ifdef LATIN_CAPITAL_LETTER_SHARP_S_UTF8
3979 # define CAP_SHARP_S LATIN_CAPITAL_LETTER_SHARP_S_UTF8
3980
3981 /* Special case these two characters, as what normally gets
3982 * returned under locale doesn't work */
3983 if (memBEGINs((char *) p, e - p, CAP_SHARP_S))
3984 {
3985 /* diag_listed_as: Can't do %s("%s") on non-UTF-8 locale; resolved to "%s". */
3986 Perl_ck_warner(aTHX_ packWARN(WARN_LOCALE),
3987 "Can't do fc(\"\\x{1E9E}\") on non-UTF-8 locale; "
3988 "resolved to \"\\x{17F}\\x{17F}\".");
3989 goto return_long_s;
3990 }
3991 else
3992 #endif
3993 if (memBEGINs((char *) p, e - p, LONG_S_T))
3994 {
3995 /* diag_listed_as: Can't do %s("%s") on non-UTF-8 locale; resolved to "%s". */
3996 Perl_ck_warner(aTHX_ packWARN(WARN_LOCALE),
3997 "Can't do fc(\"\\x{FB05}\") on non-UTF-8 locale; "
3998 "resolved to \"\\x{FB06}\".");
3999 goto return_ligature_st;
4000 }
4001
4002 #if UNICODE_MAJOR_VERSION == 3 \
4003 && UNICODE_DOT_VERSION == 0 \
4004 && UNICODE_DOT_DOT_VERSION == 1
4005 # define DOTTED_I LATIN_CAPITAL_LETTER_I_WITH_DOT_ABOVE_UTF8
4006
4007 /* And special case this on this Unicode version only, for the same
4008 * reaons the other two are special cased. They would cross the
4009 * 255/256 boundary which is forbidden under /l, and so the code
4010 * wouldn't catch that they are equivalent (which they are only in
4011 * this release) */
4012 else if (memBEGINs((char *) p, e - p, DOTTED_I)) {
4013 /* diag_listed_as: Can't do %s("%s") on non-UTF-8 locale; resolved to "%s". */
4014 Perl_ck_warner(aTHX_ packWARN(WARN_LOCALE),
4015 "Can't do fc(\"\\x{0130}\") on non-UTF-8 locale; "
4016 "resolved to \"\\x{0131}\".");
4017 goto return_dotless_i;
4018 }
4019 #endif
4020
4021 return check_locale_boundary_crossing(p, result, ustrp, lenp);
4022 }
4023 else if (! (flags & FOLD_FLAGS_NOMIX_ASCII)) {
4024 return result;
4025 }
4026 else {
4027 /* This is called when changing the case of a UTF-8-encoded
4028 * character above the ASCII range, and the result should not
4029 * contain an ASCII character. */
4030
4031 UV original; /* To store the first code point of <p> */
4032
4033 /* Look at every character in the result; if any cross the
4034 * boundary, the whole thing is disallowed */
4035 U8* s = ustrp;
4036 U8* send = ustrp + *lenp;
4037 while (s < send) {
4038 if (isASCII(*s)) {
4039 /* Crossed, have to return the original */
4040 original = valid_utf8_to_uvchr(p, lenp);
4041
4042 /* But in these instances, there is an alternative we can
4043 * return that is valid */
4044 if (original == LATIN_SMALL_LETTER_SHARP_S
4045 #ifdef LATIN_CAPITAL_LETTER_SHARP_S /* not defined in early Unicode releases */
4046 || original == LATIN_CAPITAL_LETTER_SHARP_S
4047 #endif
4048 ) {
4049 goto return_long_s;
4050 }
4051 else if (original == LATIN_SMALL_LIGATURE_LONG_S_T) {
4052 goto return_ligature_st;
4053 }
4054 #if UNICODE_MAJOR_VERSION == 3 \
4055 && UNICODE_DOT_VERSION == 0 \
4056 && UNICODE_DOT_DOT_VERSION == 1
4057
4058 else if (original == LATIN_CAPITAL_LETTER_I_WITH_DOT_ABOVE) {
4059 goto return_dotless_i;
4060 }
4061 #endif
4062 Copy(p, ustrp, *lenp, char);
4063 return original;
4064 }
4065 s += UTF8SKIP(s);
4066 }
4067
4068 /* Here, no characters crossed, result is ok as-is */
4069 return result;
4070 }
4071 }
4072
4073 /* Here, used locale rules. Convert back to UTF-8 */
4074 if (UTF8_IS_INVARIANT(result)) {
4075 *ustrp = (U8) result;
4076 *lenp = 1;
4077 }
4078 else {
4079 *ustrp = UTF8_EIGHT_BIT_HI((U8) result);
4080 *(ustrp + 1) = UTF8_EIGHT_BIT_LO((U8) result);
4081 *lenp = 2;
4082 }
4083
4084 return result;
4085
4086 return_long_s:
4087 /* Certain folds to 'ss' are prohibited by the options, but they do allow
4088 * folds to a string of two of these characters. By returning this
4089 * instead, then, e.g.,
4090 * fc("\x{1E9E}") eq fc("\x{17F}\x{17F}")
4091 * works. */
4092
4093 *lenp = 2 * STRLENs(LATIN_SMALL_LETTER_LONG_S_UTF8);
4094 Copy(LATIN_SMALL_LETTER_LONG_S_UTF8 LATIN_SMALL_LETTER_LONG_S_UTF8,
4095 ustrp, *lenp, U8);
4096 return LATIN_SMALL_LETTER_LONG_S;
4097
4098 return_ligature_st:
4099 /* Two folds to 'st' are prohibited by the options; instead we pick one and
4100 * have the other one fold to it */
4101
4102 *lenp = STRLENs(LATIN_SMALL_LIGATURE_ST_UTF8);
4103 Copy(LATIN_SMALL_LIGATURE_ST_UTF8, ustrp, *lenp, U8);
4104 return LATIN_SMALL_LIGATURE_ST;
4105
4106 #if UNICODE_MAJOR_VERSION == 3 \
4107 && UNICODE_DOT_VERSION == 0 \
4108 && UNICODE_DOT_DOT_VERSION == 1
4109
4110 return_dotless_i:
4111 *lenp = STRLENs(LATIN_SMALL_LETTER_DOTLESS_I_UTF8);
4112 Copy(LATIN_SMALL_LETTER_DOTLESS_I_UTF8, ustrp, *lenp, U8);
4113 return LATIN_SMALL_LETTER_DOTLESS_I;
4114
4115 #endif
4116
4117 }
4118
4119 bool
4120 Perl_check_utf8_print(pTHX_ const U8* s, const STRLEN len)
4121 {
4122 /* May change: warns if surrogates, non-character code points, or
4123 * non-Unicode code points are in 's' which has length 'len' bytes.
4124 * Returns TRUE if none found; FALSE otherwise. The only other validity
4125 * check is to make sure that this won't exceed the string's length nor
4126 * overflow */
4127
4128 const U8* const e = s + len;
4129 bool ok = TRUE;
4130
4131 PERL_ARGS_ASSERT_CHECK_UTF8_PRINT;
4132
4133 while (s < e) {
4134 if (UTF8SKIP(s) > len) {
4135 Perl_ck_warner_d(aTHX_ packWARN(WARN_UTF8),
4136 "%s in %s", unees, PL_op ? OP_DESC(PL_op) : "print");
4137 return FALSE;
4138 }
4139 if (UNLIKELY(isUTF8_POSSIBLY_PROBLEMATIC(*s))) {
4140 if (UNLIKELY(UTF8_IS_SUPER(s, e))) {
4141 if ( ckWARN_d(WARN_NON_UNICODE)
4142 || UNLIKELY(0 < does_utf8_overflow(s, s + len,
4143 0 /* Don't consider overlongs */
4144 )))
4145 {
4146 /* A side effect of this function will be to warn */
4147 (void) utf8n_to_uvchr(s, e - s, NULL, UTF8_WARN_SUPER);
4148 ok = FALSE;
4149 }
4150 }
4151 else if (UNLIKELY(UTF8_IS_SURROGATE(s, e))) {
4152 if (ckWARN_d(WARN_SURROGATE)) {
4153 /* This has a different warning than the one the called
4154 * function would output, so can't just call it, unlike we
4155 * do for the non-chars and above-unicodes */
4156 UV uv = utf8_to_uvchr_buf(s, e, NULL);
4157 Perl_warner(aTHX_ packWARN(WARN_SURROGATE),
4158 "Unicode surrogate U+%04" UVXf " is illegal in UTF-8",
4159 uv);
4160 ok = FALSE;
4161 }
4162 }
4163 else if ( UNLIKELY(UTF8_IS_NONCHAR(s, e))
4164 && (ckWARN_d(WARN_NONCHAR)))
4165 {
4166 /* A side effect of this function will be to warn */
4167 (void) utf8n_to_uvchr(s, e - s, NULL, UTF8_WARN_NONCHAR);
4168 ok = FALSE;
4169 }
4170 }
4171 s += UTF8SKIP(s);
4172 }
4173
4174 return ok;
4175 }
4176
4177 /*
4178 =for apidoc pv_uni_display
4179
4180 Build to the scalar C<dsv> a displayable version of the UTF-8 encoded string
4181 C<spv>, length C<len>, the displayable version being at most C<pvlim> bytes
4182 long (if longer, the rest is truncated and C<"..."> will be appended).
4183
4184 The C<flags> argument can have C<UNI_DISPLAY_ISPRINT> set to display
4185 C<isPRINT()>able characters as themselves, C<UNI_DISPLAY_BACKSLASH>
4186 to display the C<\\[nrfta\\]> as the backslashed versions (like C<"\n">)
4187 (C<UNI_DISPLAY_BACKSLASH> is preferred over C<UNI_DISPLAY_ISPRINT> for C<"\\">).
4188 C<UNI_DISPLAY_QQ> (and its alias C<UNI_DISPLAY_REGEX>) have both
4189 C<UNI_DISPLAY_BACKSLASH> and C<UNI_DISPLAY_ISPRINT> turned on.
4190
4191 Additionally, there is now C<UNI_DISPLAY_BACKSPACE> which allows C<\b> for a
4192 backspace, but only when C<UNI_DISPLAY_BACKSLASH> also is set.
4193
4194 The pointer to the PV of the C<dsv> is returned.
4195
4196 See also L</sv_uni_display>.
4197
4198 =for apidoc Amnh||UNI_DISPLAY_BACKSLASH
4199 =for apidoc Amnh||UNI_DISPLAY_BACKSPACE
4200 =for apidoc Amnh||UNI_DISPLAY_ISPRINT
4201 =for apidoc Amnh||UNI_DISPLAY_QQ
4202 =for apidoc Amnh||UNI_DISPLAY_REGEX
4203 =cut
4204 */
4205 char *
4206 Perl_pv_uni_display(pTHX_ SV *dsv, const U8 *spv, STRLEN len, STRLEN pvlim,
4207 UV flags)
4208 {
4209 int truncated = 0;
4210 const char *s, *e;
4211
4212 PERL_ARGS_ASSERT_PV_UNI_DISPLAY;
4213
4214 SvPVCLEAR(dsv);
4215 SvUTF8_off(dsv);
4216 for (s = (const char *)spv, e = s + len; s < e; s += UTF8SKIP(s)) {
4217 UV u;
4218 bool ok = 0;
4219
4220 if (pvlim && SvCUR(dsv) >= pvlim) {
4221 truncated++;
4222 break;
4223 }
4224 u = utf8_to_uvchr_buf((U8*)s, (U8*)e, 0);
4225 if (u < 256) {
4226 const U8 c = (U8) u;
4227 if (flags & UNI_DISPLAY_BACKSLASH) {
4228 if ( isMNEMONIC_CNTRL(c)
4229 && ( c != '\b'
4230 || (flags & UNI_DISPLAY_BACKSPACE)))
4231 {
4232 const char * mnemonic = cntrl_to_mnemonic(c);
4233 sv_catpvn(dsv, mnemonic, strlen(mnemonic));
4234 ok = 1;
4235 }
4236 else if (c == '\\') {
4237 sv_catpvs(dsv, "\\\\");
4238 ok = 1;
4239 }
4240 }
4241 /* isPRINT() is the locale-blind version. */
4242 if (!ok && (flags & UNI_DISPLAY_ISPRINT) && isPRINT(c)) {
4243 const char string = c;
4244 sv_catpvn(dsv, &string, 1);
4245 ok = 1;
4246 }
4247 }
4248 if (!ok)
4249 Perl_sv_catpvf(aTHX_ dsv, "\\x{%" UVxf "}", u);
4250 }
4251 if (truncated)
4252 sv_catpvs(dsv, "...");
4253
4254 return SvPVX(dsv);
4255 }
4256
4257 /*
4258 =for apidoc sv_uni_display
4259
4260 Build to the scalar C<dsv> a displayable version of the scalar C<sv>,
4261 the displayable version being at most C<pvlim> bytes long
4262 (if longer, the rest is truncated and "..." will be appended).
4263
4264 The C<flags> argument is as in L</pv_uni_display>().
4265
4266 The pointer to the PV of the C<dsv> is returned.
4267
4268 =cut
4269 */
4270 char *
4271 Perl_sv_uni_display(pTHX_ SV *dsv, SV *ssv, STRLEN pvlim, UV flags)
4272 {
4273 const char * const ptr =
4274 isREGEXP(ssv) ? RX_WRAPPED((REGEXP*)ssv) : SvPVX_const(ssv);
4275
4276 PERL_ARGS_ASSERT_SV_UNI_DISPLAY;
4277
4278 return Perl_pv_uni_display(aTHX_ dsv, (const U8*)ptr,
4279 SvCUR(ssv), pvlim, flags);
4280 }
4281
4282 /*
4283 =for apidoc foldEQ_utf8
4284
4285 Returns true if the leading portions of the strings C<s1> and C<s2> (either or
4286 both of which may be in UTF-8) are the same case-insensitively; false
4287 otherwise. How far into the strings to compare is determined by other input
4288 parameters.
4289
4290 If C<u1> is true, the string C<s1> is assumed to be in UTF-8-encoded Unicode;
4291 otherwise it is assumed to be in native 8-bit encoding. Correspondingly for
4292 C<u2> with respect to C<s2>.
4293
4294 If the byte length C<l1> is non-zero, it says how far into C<s1> to check for
4295 fold equality. In other words, C<s1>+C<l1> will be used as a goal to reach.
4296 The scan will not be considered to be a match unless the goal is reached, and
4297 scanning won't continue past that goal. Correspondingly for C<l2> with respect
4298 to C<s2>.
4299
4300 If C<pe1> is non-C<NULL> and the pointer it points to is not C<NULL>, that
4301 pointer is considered an end pointer to the position 1 byte past the maximum
4302 point in C<s1> beyond which scanning will not continue under any circumstances.
4303 (This routine assumes that UTF-8 encoded input strings are not malformed;
4304 malformed input can cause it to read past C<pe1>). This means that if both
4305 C<l1> and C<pe1> are specified, and C<pe1> is less than C<s1>+C<l1>, the match
4306 will never be successful because it can never
4307 get as far as its goal (and in fact is asserted against). Correspondingly for
4308 C<pe2> with respect to C<s2>.
4309
4310 At least one of C<s1> and C<s2> must have a goal (at least one of C<l1> and
4311 C<l2> must be non-zero), and if both do, both have to be
4312 reached for a successful match. Also, if the fold of a character is multiple
4313 characters, all of them must be matched (see tr21 reference below for
4314 'folding').
4315
4316 Upon a successful match, if C<pe1> is non-C<NULL>,
4317 it will be set to point to the beginning of the I<next> character of C<s1>
4318 beyond what was matched. Correspondingly for C<pe2> and C<s2>.
4319
4320 For case-insensitiveness, the "casefolding" of Unicode is used
4321 instead of upper/lowercasing both the characters, see
4322 L<https://www.unicode.org/reports/tr21/> (Case Mappings).
4323
4324 =for apidoc Cmnh||FOLDEQ_UTF8_NOMIX_ASCII
4325 =for apidoc Cmnh||FOLDEQ_LOCALE
4326 =for apidoc Cmnh||FOLDEQ_S1_ALREADY_FOLDED
4327 =for apidoc Cmnh||FOLDEQ_S1_FOLDS_SANE
4328 =for apidoc Cmnh||FOLDEQ_S2_ALREADY_FOLDED
4329 =for apidoc Cmnh||FOLDEQ_S2_FOLDS_SANE
4330
4331 =cut */
4332
4333 /* A flags parameter has been added which may change, and hence isn't
4334 * externally documented. Currently it is:
4335 * 0 for as-documented above
4336 * FOLDEQ_UTF8_NOMIX_ASCII meaning that if a non-ASCII character folds to an
4337 ASCII one, to not match
4338 * FOLDEQ_LOCALE is set iff the rules from the current underlying
4339 * locale are to be used.
4340 * FOLDEQ_S1_ALREADY_FOLDED s1 has already been folded before calling this
4341 * routine. This allows that step to be skipped.
4342 * Currently, this requires s1 to be encoded as UTF-8
4343 * (u1 must be true), which is asserted for.
4344 * FOLDEQ_S1_FOLDS_SANE With either NOMIX_ASCII or LOCALE, no folds may
4345 * cross certain boundaries. Hence, the caller should
4346 * let this function do the folding instead of
4347 * pre-folding. This code contains an assertion to
4348 * that effect. However, if the caller knows what
4349 * it's doing, it can pass this flag to indicate that,
4350 * and the assertion is skipped.
4351 * FOLDEQ_S2_ALREADY_FOLDED Similar to FOLDEQ_S1_ALREADY_FOLDED, but applies
4352 * to s2, and s2 doesn't have to be UTF-8 encoded.
4353 * This introduces an asymmetry to save a few branches
4354 * in a loop. Currently, this is not a problem, as
4355 * never are both inputs pre-folded. Simply call this
4356 * function with the pre-folded one as the second
4357 * string.
4358 * FOLDEQ_S2_FOLDS_SANE
4359 */
4360
4361 I32
4362 Perl_foldEQ_utf8_flags(pTHX_ const char *s1, char **pe1, UV l1, bool u1,
4363 const char *s2, char **pe2, UV l2, bool u2,
4364 U32 flags)
4365 {
4366 const U8 *p1 = (const U8*)s1; /* Point to current char */
4367 const U8 *p2 = (const U8*)s2;
4368 const U8 *g1 = NULL; /* goal for s1 */
4369 const U8 *g2 = NULL;
4370 const U8 *e1 = NULL; /* Don't scan s1 past this */
4371 U8 *f1 = NULL; /* Point to current folded */
4372 const U8 *e2 = NULL;
4373 U8 *f2 = NULL;
4374 STRLEN n1 = 0, n2 = 0; /* Number of bytes in current char */
4375 U8 foldbuf1[UTF8_MAXBYTES_CASE+1];
4376 U8 foldbuf2[UTF8_MAXBYTES_CASE+1];
4377 U8 flags_for_folder = FOLD_FLAGS_FULL;
4378
4379 PERL_ARGS_ASSERT_FOLDEQ_UTF8_FLAGS;
4380
4381 assert( ! ( (flags & (FOLDEQ_UTF8_NOMIX_ASCII | FOLDEQ_LOCALE))
4382 && (( (flags & FOLDEQ_S1_ALREADY_FOLDED)
4383 && !(flags & FOLDEQ_S1_FOLDS_SANE))
4384 || ( (flags & FOLDEQ_S2_ALREADY_FOLDED)
4385 && !(flags & FOLDEQ_S2_FOLDS_SANE)))));
4386 /* The algorithm is to trial the folds without regard to the flags on
4387 * the first line of the above assert(), and then see if the result
4388 * violates them. This means that the inputs can't be pre-folded to a
4389 * violating result, hence the assert. This could be changed, with the
4390 * addition of extra tests here for the already-folded case, which would
4391 * slow it down. That cost is more than any possible gain for when these
4392 * flags are specified, as the flags indicate /il or /iaa matching which
4393 * is less common than /iu, and I (khw) also believe that real-world /il
4394 * and /iaa matches are most likely to involve code points 0-255, and this
4395 * function only under rare conditions gets called for 0-255. */
4396
4397 if (flags & FOLDEQ_LOCALE) {
4398 if (IN_UTF8_CTYPE_LOCALE) {
4399 if (UNLIKELY(IN_UTF8_TURKIC_LOCALE)) {
4400 flags_for_folder |= FOLD_FLAGS_LOCALE;
4401 }
4402 else {
4403 flags &= ~FOLDEQ_LOCALE;
4404 }
4405 }
4406 else {
4407 flags_for_folder |= FOLD_FLAGS_LOCALE;
4408 }
4409 }
4410 if (flags & FOLDEQ_UTF8_NOMIX_ASCII) {
4411 flags_for_folder |= FOLD_FLAGS_NOMIX_ASCII;
4412 }
4413
4414 if (pe1) {
4415 e1 = *(U8**)pe1;
4416 }
4417
4418 if (l1) {
4419 g1 = (const U8*)s1 + l1;
4420 }
4421
4422 if (pe2) {
4423 e2 = *(U8**)pe2;
4424 }
4425
4426 if (l2) {
4427 g2 = (const U8*)s2 + l2;
4428 }
4429
4430 /* Must have at least one goal */
4431 assert(g1 || g2);
4432
4433 if (g1) {
4434
4435 /* Will never match if goal is out-of-bounds */
4436 assert(! e1 || e1 >= g1);
4437
4438 /* Here, there isn't an end pointer, or it is beyond the goal. We
4439 * only go as far as the goal */
4440 e1 = g1;
4441 }
4442 else {
4443 assert(e1); /* Must have an end for looking at s1 */
4444 }
4445
4446 /* Same for goal for s2 */
4447 if (g2) {
4448 assert(! e2 || e2 >= g2);
4449 e2 = g2;
4450 }
4451 else {
4452 assert(e2);
4453 }
4454
4455 /* If both operands are already folded, we could just do a memEQ on the
4456 * whole strings at once, but it would be better if the caller realized
4457 * this and didn't even call us */
4458
4459 /* Look through both strings, a character at a time */
4460 while (p1 < e1 && p2 < e2) {
4461
4462 /* If at the beginning of a new character in s1, get its fold to use
4463 * and the length of the fold. */
4464 if (n1 == 0) {
4465 if (flags & FOLDEQ_S1_ALREADY_FOLDED) {
4466 f1 = (U8 *) p1;
4467 assert(u1);
4468 n1 = UTF8SKIP(f1);
4469 }
4470 else {
4471 if (isASCII(*p1) && ! (flags & FOLDEQ_LOCALE)) {
4472
4473 /* We have to forbid mixing ASCII with non-ASCII if the
4474 * flags so indicate. And, we can short circuit having to
4475 * call the general functions for this common ASCII case,
4476 * all of whose non-locale folds are also ASCII, and hence
4477 * UTF-8 invariants, so the UTF8ness of the strings is not
4478 * relevant. */
4479 if ((flags & FOLDEQ_UTF8_NOMIX_ASCII) && ! isASCII(*p2)) {
4480 return 0;
4481 }
4482 n1 = 1;
4483 *foldbuf1 = toFOLD(*p1);
4484 }
4485 else if (u1) {
4486 _toFOLD_utf8_flags(p1, e1, foldbuf1, &n1, flags_for_folder);
4487 }
4488 else { /* Not UTF-8, get UTF-8 fold */
4489 _to_uni_fold_flags(*p1, foldbuf1, &n1, flags_for_folder);
4490 }
4491 f1 = foldbuf1;
4492 }
4493 }
4494
4495 if (n2 == 0) { /* Same for s2 */
4496 if (flags & FOLDEQ_S2_ALREADY_FOLDED) {
4497
4498 /* Point to the already-folded character. But for non-UTF-8
4499 * variants, convert to UTF-8 for the algorithm below */
4500 if (UTF8_IS_INVARIANT(*p2)) {
4501 f2 = (U8 *) p2;
4502 n2 = 1;
4503 }
4504 else if (u2) {
4505 f2 = (U8 *) p2;
4506 n2 = UTF8SKIP(f2);
4507 }
4508 else {
4509 foldbuf2[0] = UTF8_EIGHT_BIT_HI(*p2);
4510 foldbuf2[1] = UTF8_EIGHT_BIT_LO(*p2);
4511 f2 = foldbuf2;
4512 n2 = 2;
4513 }
4514 }
4515 else {
4516 if (isASCII(*p2) && ! (flags & FOLDEQ_LOCALE)) {
4517 if ((flags & FOLDEQ_UTF8_NOMIX_ASCII) && ! isASCII(*p1)) {
4518 return 0;
4519 }
4520 n2 = 1;
4521 *foldbuf2 = toFOLD(*p2);
4522 }
4523 else if (u2) {
4524 _toFOLD_utf8_flags(p2, e2, foldbuf2, &n2, flags_for_folder);
4525 }
4526 else {
4527 _to_uni_fold_flags(*p2, foldbuf2, &n2, flags_for_folder);
4528 }
4529 f2 = foldbuf2;
4530 }
4531 }
4532
4533 /* Here f1 and f2 point to the beginning of the strings to compare.
4534 * These strings are the folds of the next character from each input
4535 * string, stored in UTF-8. */
4536
4537 /* While there is more to look for in both folds, see if they
4538 * continue to match */
4539 while (n1 && n2) {
4540 U8 fold_length = UTF8SKIP(f1);
4541 if (fold_length != UTF8SKIP(f2)
4542 || (fold_length == 1 && *f1 != *f2) /* Short circuit memNE
4543 function call for single
4544 byte */
4545 || memNE((char*)f1, (char*)f2, fold_length))
4546 {
4547 return 0; /* mismatch */
4548 }
4549
4550 /* Here, they matched, advance past them */
4551 n1 -= fold_length;
4552 f1 += fold_length;
4553 n2 -= fold_length;
4554 f2 += fold_length;
4555 }
4556
4557 /* When reach the end of any fold, advance the input past it */
4558 if (n1 == 0) {
4559 p1 += u1 ? UTF8SKIP(p1) : 1;
4560 }
4561 if (n2 == 0) {
4562 p2 += u2 ? UTF8SKIP(p2) : 1;
4563 }
4564 } /* End of loop through both strings */
4565
4566 /* A match is defined by each scan that specified an explicit length
4567 * reaching its final goal, and the other not having matched a partial
4568 * character (which can happen when the fold of a character is more than one
4569 * character). */
4570 if (! ((g1 == 0 || p1 == g1) && (g2 == 0 || p2 == g2)) || n1 || n2) {
4571 return 0;
4572 }
4573
4574 /* Successful match. Set output pointers */
4575 if (pe1) {
4576 *pe1 = (char*)p1;
4577 }
4578 if (pe2) {
4579 *pe2 = (char*)p2;
4580 }
4581 return 1;
4582 }
4583
4584 /*
4585 * ex: set ts=8 sts=4 sw=4 et:
4586 */
4587