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utf8.c: Static fnc always passed non-null
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a0ed51b3
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1/* utf8.c
2 *
1129b882 3 * Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008
b94e2f88 4 * by Larry Wall and others
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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/*
4ac71550
TC
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 *
cdad3b53 16 * [p.603 of _The Lord of the Rings_, IV/I: "The Taming of Sméagol"]
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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,
4ac71550 20 * as is the custom in the West, if you wish to be answered?'
cdad3b53 21 * --Gandalf, addressing Théoden's door wardens
4ac71550
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22 *
23 * [p.508 of _The Lord of the Rings_, III/vi: "The King of the Golden Hall"]
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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.
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27 *
28 * [p.512 of _The Lord of the Rings_, III/vi: "The King of the Golden Hall"]
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29 */
30
31#include "EXTERN.h"
864dbfa3 32#define PERL_IN_UTF8_C
a0ed51b3 33#include "perl.h"
b992490d 34#include "invlist_inline.h"
afde5508 35#include "uni_keywords.h"
a0ed51b3 36
806547a7 37static const char malformed_text[] = "Malformed UTF-8 character";
27da23d5 38static const char unees[] =
806547a7 39 "Malformed UTF-8 character (unexpected end of string)";
fb7e7255
KW
40
41/* Be sure to synchronize this message with the similar one in regcomp.c */
760c7c2f 42static const char cp_above_legal_max[] =
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43 "Use of code point 0x%" UVXf " is not allowed; the"
44 " permissible max is 0x%" UVXf;
760c7c2f 45
d22ec717 46#define MAX_EXTERNALLY_LEGAL_CP ((UV) (IV_MAX))
901b21bf 47
48ef279e 48/*
ccfc67b7 49=head1 Unicode Support
7fefc6c1 50These are various utility functions for manipulating UTF8-encoded
72d33970 51strings. For the uninitiated, this is a method of representing arbitrary
61296642 52Unicode characters as a variable number of bytes, in such a way that
56da48f7
DM
53characters in the ASCII range are unmodified, and a zero byte never appears
54within non-zero characters.
166f8a29 55
eaf7a4d2
CS
56=cut
57*/
58
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59void
60Perl__force_out_malformed_utf8_message(pTHX_
61 const U8 *const p, /* First byte in UTF-8 sequence */
62 const U8 * const e, /* Final byte in sequence (may include
63 multiple chars */
64 const U32 flags, /* Flags to pass to utf8n_to_uvchr(),
65 usually 0, or some DISALLOW flags */
66 const bool die_here) /* If TRUE, this function does not return */
67{
68 /* This core-only function is to be called when a malformed UTF-8 character
69 * is found, in order to output the detailed information about the
70 * malformation before dieing. The reason it exists is for the occasions
71 * when such a malformation is fatal, but warnings might be turned off, so
72 * that normally they would not be actually output. This ensures that they
73 * do get output. Because a sequence may be malformed in more than one
74 * way, multiple messages may be generated, so we can't make them fatal, as
75 * that would cause the first one to die.
76 *
77 * Instead we pretend -W was passed to perl, then die afterwards. The
78 * flexibility is here to return to the caller so they can finish up and
79 * die themselves */
80 U32 errors;
81
82 PERL_ARGS_ASSERT__FORCE_OUT_MALFORMED_UTF8_MESSAGE;
83
84 ENTER;
c15a80f3 85 SAVEI8(PL_dowarn);
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86 SAVESPTR(PL_curcop);
87
88 PL_dowarn = G_WARN_ALL_ON|G_WARN_ON;
89 if (PL_curcop) {
90 PL_curcop->cop_warnings = pWARN_ALL;
91 }
92
93 (void) utf8n_to_uvchr_error(p, e - p, NULL, flags & ~UTF8_CHECK_ONLY, &errors);
94
95 LEAVE;
96
97 if (! errors) {
98 Perl_croak(aTHX_ "panic: _force_out_malformed_utf8_message should"
99 " be called only when there are errors found");
100 }
101
102 if (die_here) {
103 Perl_croak(aTHX_ "Malformed UTF-8 character (fatal)");
104 }
105}
106
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107STATIC HV *
108S_new_msg_hv(pTHX_ const char * const message, /* The message text */
109 U32 categories, /* Packed warning categories */
110 U32 flag) /* Flag associated with this message */
111{
112 /* Creates, populates, and returns an HV* that describes an error message
113 * for the translators between UTF8 and code point */
114
115 SV* msg_sv = newSVpv(message, 0);
116 SV* category_sv = newSVuv(categories);
117 SV* flag_bit_sv = newSVuv(flag);
118
119 HV* msg_hv = newHV();
120
121 PERL_ARGS_ASSERT_NEW_MSG_HV;
122
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123 (void) hv_stores(msg_hv, "text", msg_sv);
124 (void) hv_stores(msg_hv, "warn_categories", category_sv);
125 (void) hv_stores(msg_hv, "flag_bit", flag_bit_sv);
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126
127 return msg_hv;
128}
129
eaf7a4d2 130/*
378516de 131=for apidoc uvoffuni_to_utf8_flags
eebe1485 132
a27992cc 133THIS FUNCTION SHOULD BE USED IN ONLY VERY SPECIALIZED CIRCUMSTANCES.
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134Instead, B<Almost all code should use L</uvchr_to_utf8> or
135L</uvchr_to_utf8_flags>>.
a27992cc 136
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137This function is like them, but the input is a strict Unicode
138(as opposed to native) code point. Only in very rare circumstances should code
139not be using the native code point.
949cf498 140
efa9cd84 141For details, see the description for L</uvchr_to_utf8_flags>.
949cf498 142
eebe1485
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143=cut
144*/
145
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146U8 *
147Perl_uvoffuni_to_utf8_flags(pTHX_ U8 *d, UV uv, const UV flags)
148{
149 PERL_ARGS_ASSERT_UVOFFUNI_TO_UTF8_FLAGS;
150
151 return uvoffuni_to_utf8_flags_msgs(d, uv, flags, NULL);
152}
153
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154/* All these formats take a single UV code point argument */
155const char surrogate_cp_format[] = "UTF-16 surrogate U+%04" UVXf;
156const char nonchar_cp_format[] = "Unicode non-character U+%04" UVXf
157 " is not recommended for open interchange";
158const char super_cp_format[] = "Code point 0x%" UVXf " is not Unicode,"
159 " may not be portable";
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160const char perl_extended_cp_format[] = "Code point 0x%" UVXf " is not" \
161 " Unicode, requires a Perl extension," \
162 " and so is not portable";
c94c2f39 163
33f38593 164#define HANDLE_UNICODE_SURROGATE(uv, flags, msgs) \
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165 STMT_START { \
166 if (flags & UNICODE_WARN_SURROGATE) { \
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167 U32 category = packWARN(WARN_SURROGATE); \
168 const char * format = surrogate_cp_format; \
169 if (msgs) { \
170 *msgs = new_msg_hv(Perl_form(aTHX_ format, uv), \
171 category, \
172 UNICODE_GOT_SURROGATE); \
173 } \
174 else { \
175 Perl_ck_warner_d(aTHX_ category, format, uv); \
176 } \
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177 } \
178 if (flags & UNICODE_DISALLOW_SURROGATE) { \
179 return NULL; \
180 } \
181 } STMT_END;
182
33f38593 183#define HANDLE_UNICODE_NONCHAR(uv, flags, msgs) \
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184 STMT_START { \
185 if (flags & UNICODE_WARN_NONCHAR) { \
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186 U32 category = packWARN(WARN_NONCHAR); \
187 const char * format = nonchar_cp_format; \
188 if (msgs) { \
189 *msgs = new_msg_hv(Perl_form(aTHX_ format, uv), \
190 category, \
191 UNICODE_GOT_NONCHAR); \
192 } \
193 else { \
194 Perl_ck_warner_d(aTHX_ category, format, uv); \
195 } \
8ee1cdcb
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196 } \
197 if (flags & UNICODE_DISALLOW_NONCHAR) { \
198 return NULL; \
199 } \
200 } STMT_END;
201
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202/* Use shorter names internally in this file */
203#define SHIFT UTF_ACCUMULATION_SHIFT
204#undef MARK
205#define MARK UTF_CONTINUATION_MARK
206#define MASK UTF_CONTINUATION_MASK
207
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208/*
209=for apidoc uvchr_to_utf8_flags_msgs
210
211THIS FUNCTION SHOULD BE USED IN ONLY VERY SPECIALIZED CIRCUMSTANCES.
212
213Most code should use C<L</uvchr_to_utf8_flags>()> rather than call this directly.
214
215This function is for code that wants any warning and/or error messages to be
216returned to the caller rather than be displayed. All messages that would have
884a31ee 217been displayed if all lexical warnings are enabled will be returned.
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218
219It is just like C<L</uvchr_to_utf8_flags>> but it takes an extra parameter
220placed after all the others, C<msgs>. If this parameter is 0, this function
221behaves identically to C<L</uvchr_to_utf8_flags>>. Otherwise, C<msgs> should
222be a pointer to an C<HV *> variable, in which this function creates a new HV to
223contain any appropriate messages. The hash has three key-value pairs, as
224follows:
225
226=over 4
227
228=item C<text>
229
230The text of the message as a C<SVpv>.
231
232=item C<warn_categories>
233
234The warning category (or categories) packed into a C<SVuv>.
235
236=item C<flag>
237
238A single flag bit associated with this message, in a C<SVuv>.
239The bit corresponds to some bit in the C<*errors> return value,
240such as C<UNICODE_GOT_SURROGATE>.
241
242=back
243
244It's important to note that specifying this parameter as non-null will cause
245any warnings this function would otherwise generate to be suppressed, and
246instead be placed in C<*msgs>. The caller can check the lexical warnings state
247(or not) when choosing what to do with the returned messages.
248
249The caller, of course, is responsible for freeing any returned HV.
250
251=cut
252*/
253
254/* Undocumented; we don't want people using this. Instead they should use
255 * uvchr_to_utf8_flags_msgs() */
dfe13c55 256U8 *
33f38593 257Perl_uvoffuni_to_utf8_flags_msgs(pTHX_ U8 *d, UV uv, const UV flags, HV** msgs)
a0ed51b3 258{
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259 PERL_ARGS_ASSERT_UVOFFUNI_TO_UTF8_FLAGS_MSGS;
260
261 if (msgs) {
262 *msgs = NULL;
263 }
7918f24d 264
2d1545e5 265 if (OFFUNI_IS_INVARIANT(uv)) {
4c8cd605 266 *d++ = LATIN1_TO_NATIVE(uv);
d9432125
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267 return d;
268 }
facc1dc2 269
3ea68d71 270 if (uv <= MAX_UTF8_TWO_BYTE) {
facc1dc2
KW
271 *d++ = I8_TO_NATIVE_UTF8(( uv >> SHIFT) | UTF_START_MARK(2));
272 *d++ = I8_TO_NATIVE_UTF8(( uv & MASK) | MARK);
3ea68d71
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273 return d;
274 }
d9432125 275
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276 /* Not 2-byte; test for and handle 3-byte result. In the test immediately
277 * below, the 16 is for start bytes E0-EF (which are all the possible ones
278 * for 3 byte characters). The 2 is for 2 continuation bytes; these each
279 * contribute SHIFT bits. This yields 0x4000 on EBCDIC platforms, 0x1_0000
280 * on ASCII; so 3 bytes covers the range 0x400-0x3FFF on EBCDIC;
281 * 0x800-0xFFFF on ASCII */
282 if (uv < (16 * (1U << (2 * SHIFT)))) {
283 *d++ = I8_TO_NATIVE_UTF8(( uv >> ((3 - 1) * SHIFT)) | UTF_START_MARK(3));
284 *d++ = I8_TO_NATIVE_UTF8(((uv >> ((2 - 1) * SHIFT)) & MASK) | MARK);
285 *d++ = I8_TO_NATIVE_UTF8(( uv /* (1 - 1) */ & MASK) | MARK);
286
287#ifndef EBCDIC /* These problematic code points are 4 bytes on EBCDIC, so
288 aren't tested here */
289 /* The most likely code points in this range are below the surrogates.
290 * Do an extra test to quickly exclude those. */
291 if (UNLIKELY(uv >= UNICODE_SURROGATE_FIRST)) {
292 if (UNLIKELY( UNICODE_IS_32_CONTIGUOUS_NONCHARS(uv)
293 || UNICODE_IS_END_PLANE_NONCHAR_GIVEN_NOT_SUPER(uv)))
294 {
33f38593 295 HANDLE_UNICODE_NONCHAR(uv, flags, msgs);
8ee1cdcb
KW
296 }
297 else if (UNLIKELY(UNICODE_IS_SURROGATE(uv))) {
33f38593 298 HANDLE_UNICODE_SURROGATE(uv, flags, msgs);
760c7c2f 299 }
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300 }
301#endif
302 return d;
303 }
304
305 /* Not 3-byte; that means the code point is at least 0x1_0000 on ASCII
306 * platforms, and 0x4000 on EBCDIC. There are problematic cases that can
307 * happen starting with 4-byte characters on ASCII platforms. We unify the
308 * code for these with EBCDIC, even though some of them require 5-bytes on
309 * those, because khw believes the code saving is worth the very slight
310 * performance hit on these high EBCDIC code points. */
311
312 if (UNLIKELY(UNICODE_IS_SUPER(uv))) {
d22ec717
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313 if (UNLIKELY(uv > MAX_EXTERNALLY_LEGAL_CP)) {
314 Perl_croak(aTHX_ cp_above_legal_max, uv, MAX_EXTERNALLY_LEGAL_CP);
a5bf80e0 315 }
33f38593
KW
316 if ( (flags & UNICODE_WARN_SUPER)
317 || ( (flags & UNICODE_WARN_PERL_EXTENDED)
0a8a1a5b 318 && UNICODE_IS_PERL_EXTENDED(uv)))
a5bf80e0 319 {
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320 const char * format = super_cp_format;
321 U32 category = packWARN(WARN_NON_UNICODE);
322 U32 flag = UNICODE_GOT_SUPER;
323
324 /* Choose the more dire applicable warning */
325 if (UNICODE_IS_PERL_EXTENDED(uv)) {
326 format = perl_extended_cp_format;
327 if (flags & (UNICODE_WARN_PERL_EXTENDED
328 |UNICODE_DISALLOW_PERL_EXTENDED))
329 {
330 flag = UNICODE_GOT_PERL_EXTENDED;
331 }
332 }
a5bf80e0 333
33f38593
KW
334 if (msgs) {
335 *msgs = new_msg_hv(Perl_form(aTHX_ format, uv),
336 category, flag);
337 }
338 else {
339 Perl_ck_warner_d(aTHX_ packWARN(WARN_NON_UNICODE), format, uv);
340 }
a5bf80e0 341 }
56576a04 342 if ( (flags & UNICODE_DISALLOW_SUPER)
0a8a1a5b
KW
343 || ( (flags & UNICODE_DISALLOW_PERL_EXTENDED)
344 && UNICODE_IS_PERL_EXTENDED(uv)))
a5bf80e0
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345 {
346 return NULL;
347 }
348 }
ba6ed43c 349 else if (UNLIKELY(UNICODE_IS_END_PLANE_NONCHAR_GIVEN_NOT_SUPER(uv))) {
33f38593 350 HANDLE_UNICODE_NONCHAR(uv, flags, msgs);
507b9800 351 }
d9432125 352
ba6ed43c
KW
353 /* Test for and handle 4-byte result. In the test immediately below, the
354 * 8 is for start bytes F0-F7 (which are all the possible ones for 4 byte
355 * characters). The 3 is for 3 continuation bytes; these each contribute
356 * SHIFT bits. This yields 0x4_0000 on EBCDIC platforms, 0x20_0000 on
357 * ASCII, so 4 bytes covers the range 0x4000-0x3_FFFF on EBCDIC;
358 * 0x1_0000-0x1F_FFFF on ASCII */
359 if (uv < (8 * (1U << (3 * SHIFT)))) {
360 *d++ = I8_TO_NATIVE_UTF8(( uv >> ((4 - 1) * SHIFT)) | UTF_START_MARK(4));
361 *d++ = I8_TO_NATIVE_UTF8(((uv >> ((3 - 1) * SHIFT)) & MASK) | MARK);
362 *d++ = I8_TO_NATIVE_UTF8(((uv >> ((2 - 1) * SHIFT)) & MASK) | MARK);
363 *d++ = I8_TO_NATIVE_UTF8(( uv /* (1 - 1) */ & MASK) | MARK);
364
365#ifdef EBCDIC /* These were handled on ASCII platforms in the code for 3-byte
366 characters. The end-plane non-characters for EBCDIC were
367 handled just above */
368 if (UNLIKELY(UNICODE_IS_32_CONTIGUOUS_NONCHARS(uv))) {
33f38593 369 HANDLE_UNICODE_NONCHAR(uv, flags, msgs);
d528804a 370 }
ba6ed43c 371 else if (UNLIKELY(UNICODE_IS_SURROGATE(uv))) {
33f38593 372 HANDLE_UNICODE_SURROGATE(uv, flags, msgs);
ba6ed43c
KW
373 }
374#endif
375
376 return d;
377 }
378
379 /* Not 4-byte; that means the code point is at least 0x20_0000 on ASCII
380 * platforms, and 0x4000 on EBCDIC. At this point we switch to a loop
381 * format. The unrolled version above turns out to not save all that much
382 * time, and at these high code points (well above the legal Unicode range
383 * on ASCII platforms, and well above anything in common use in EBCDIC),
384 * khw believes that less code outweighs slight performance gains. */
385
d9432125 386 {
5aaebcb3 387 STRLEN len = OFFUNISKIP(uv);
1d72bdf6
NIS
388 U8 *p = d+len-1;
389 while (p > d) {
957a9e81
KW
390 *p-- = I8_TO_NATIVE_UTF8((uv & MASK) | MARK);
391 uv >>= SHIFT;
1d72bdf6 392 }
4c8cd605 393 *p = I8_TO_NATIVE_UTF8((uv & UTF_START_MASK(len)) | UTF_START_MARK(len));
1d72bdf6
NIS
394 return d+len;
395 }
a0ed51b3 396}
a5bf80e0 397
646ca15d 398/*
07693fe6
KW
399=for apidoc uvchr_to_utf8
400
bcb1a2d4 401Adds the UTF-8 representation of the native code point C<uv> to the end
f2fc1b45 402of the string C<d>; C<d> should have at least C<UVCHR_SKIP(uv)+1> (up to
c749c9fd
KW
403C<UTF8_MAXBYTES+1>) free bytes available. The return value is the pointer to
404the byte after the end of the new character. In other words,
07693fe6
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405
406 d = uvchr_to_utf8(d, uv);
407
408is the recommended wide native character-aware way of saying
409
410 *(d++) = uv;
411
d22ec717
KW
412This function accepts any code point from 0..C<IV_MAX> as input.
413C<IV_MAX> is typically 0x7FFF_FFFF in a 32-bit word.
760c7c2f
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414
415It is possible to forbid or warn on non-Unicode code points, or those that may
416be problematic by using L</uvchr_to_utf8_flags>.
de69f3af 417
07693fe6
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418=cut
419*/
420
de69f3af
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421/* This is also a macro */
422PERL_CALLCONV U8* Perl_uvchr_to_utf8(pTHX_ U8 *d, UV uv);
423
07693fe6
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424U8 *
425Perl_uvchr_to_utf8(pTHX_ U8 *d, UV uv)
426{
de69f3af 427 return uvchr_to_utf8(d, uv);
07693fe6
KW
428}
429
de69f3af
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430/*
431=for apidoc uvchr_to_utf8_flags
432
433Adds the UTF-8 representation of the native code point C<uv> to the end
f2fc1b45 434of the string C<d>; C<d> should have at least C<UVCHR_SKIP(uv)+1> (up to
c749c9fd
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435C<UTF8_MAXBYTES+1>) free bytes available. The return value is the pointer to
436the byte after the end of the new character. In other words,
de69f3af
KW
437
438 d = uvchr_to_utf8_flags(d, uv, flags);
439
440or, in most cases,
441
442 d = uvchr_to_utf8_flags(d, uv, 0);
443
444This is the Unicode-aware way of saying
445
446 *(d++) = uv;
447
d22ec717
KW
448If C<flags> is 0, this function accepts any code point from 0..C<IV_MAX> as
449input. C<IV_MAX> is typically 0x7FFF_FFFF in a 32-bit word.
760c7c2f
KW
450
451Specifying C<flags> can further restrict what is allowed and not warned on, as
452follows:
de69f3af 453
796b6530 454If C<uv> is a Unicode surrogate code point and C<UNICODE_WARN_SURROGATE> is set,
7ee537e6
KW
455the function will raise a warning, provided UTF8 warnings are enabled. If
456instead C<UNICODE_DISALLOW_SURROGATE> is set, the function will fail and return
457NULL. If both flags are set, the function will both warn and return NULL.
de69f3af 458
760c7c2f
KW
459Similarly, the C<UNICODE_WARN_NONCHAR> and C<UNICODE_DISALLOW_NONCHAR> flags
460affect how the function handles a Unicode non-character.
93e6dbd6 461
760c7c2f
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462And likewise, the C<UNICODE_WARN_SUPER> and C<UNICODE_DISALLOW_SUPER> flags
463affect the handling of code points that are above the Unicode maximum of
4640x10FFFF. Languages other than Perl may not be able to accept files that
465contain these.
93e6dbd6
KW
466
467The flag C<UNICODE_WARN_ILLEGAL_INTERCHANGE> selects all three of
468the above WARN flags; and C<UNICODE_DISALLOW_ILLEGAL_INTERCHANGE> selects all
ecc1615f
KW
469three DISALLOW flags. C<UNICODE_DISALLOW_ILLEGAL_INTERCHANGE> restricts the
470allowed inputs to the strict UTF-8 traditionally defined by Unicode.
471Similarly, C<UNICODE_WARN_ILLEGAL_C9_INTERCHANGE> and
472C<UNICODE_DISALLOW_ILLEGAL_C9_INTERCHANGE> are shortcuts to select the
473above-Unicode and surrogate flags, but not the non-character ones, as
474defined in
475L<Unicode Corrigendum #9|http://www.unicode.org/versions/corrigendum9.html>.
476See L<perlunicode/Noncharacter code points>.
93e6dbd6 477
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478Extremely high code points were never specified in any standard, and require an
479extension to UTF-8 to express, which Perl does. It is likely that programs
480written in something other than Perl would not be able to read files that
481contain these; nor would Perl understand files written by something that uses a
482different extension. For these reasons, there is a separate set of flags that
483can warn and/or disallow these extremely high code points, even if other
484above-Unicode ones are accepted. They are the C<UNICODE_WARN_PERL_EXTENDED>
485and C<UNICODE_DISALLOW_PERL_EXTENDED> flags. For more information see
486L</C<UTF8_GOT_PERL_EXTENDED>>. Of course C<UNICODE_DISALLOW_SUPER> will
487treat all above-Unicode code points, including these, as malformations. (Note
488that the Unicode standard considers anything above 0x10FFFF to be illegal, but
489there are standards predating it that allow up to 0x7FFF_FFFF (2**31 -1))
490
491A somewhat misleadingly named synonym for C<UNICODE_WARN_PERL_EXTENDED> is
492retained for backward compatibility: C<UNICODE_WARN_ABOVE_31_BIT>. Similarly,
493C<UNICODE_DISALLOW_ABOVE_31_BIT> is usable instead of the more accurately named
7c4a22ed
KW
494C<UNICODE_DISALLOW_PERL_EXTENDED>. The names are misleading because on EBCDIC
495platforms,these flags can apply to code points that actually do fit in 31 bits.
496The new names accurately describe the situation in all cases.
de69f3af 497
de69f3af
KW
498=cut
499*/
500
501/* This is also a macro */
502PERL_CALLCONV U8* Perl_uvchr_to_utf8_flags(pTHX_ U8 *d, UV uv, UV flags);
503
07693fe6
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504U8 *
505Perl_uvchr_to_utf8_flags(pTHX_ U8 *d, UV uv, UV flags)
506{
de69f3af 507 return uvchr_to_utf8_flags(d, uv, flags);
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508}
509
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510#ifndef UV_IS_QUAD
511
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512STATIC int
513S_is_utf8_cp_above_31_bits(const U8 * const s,
514 const U8 * const e,
515 const bool consider_overlongs)
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516{
517 /* Returns TRUE if the first code point represented by the Perl-extended-
518 * UTF-8-encoded string starting at 's', and looking no further than 'e -
519 * 1' doesn't fit into 31 bytes. That is, that if it is >= 2**31.
520 *
521 * The function handles the case where the input bytes do not include all
522 * the ones necessary to represent a full character. That is, they may be
523 * the intial bytes of the representation of a code point, but possibly
524 * the final ones necessary for the complete representation may be beyond
525 * 'e - 1'.
526 *
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527 * The function also can handle the case where the input is an overlong
528 * sequence. If 'consider_overlongs' is 0, the function assumes the
529 * input is not overlong, without checking, and will return based on that
530 * assumption. If this parameter is 1, the function will go to the trouble
531 * of figuring out if it actually evaluates to above or below 31 bits.
83dc0f42 532 *
e050c007 533 * The sequence is otherwise assumed to be well-formed, without checking.
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534 */
535
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536 const STRLEN len = e - s;
537 int is_overlong;
538
539 PERL_ARGS_ASSERT_IS_UTF8_CP_ABOVE_31_BITS;
540
541 assert(! UTF8_IS_INVARIANT(*s) && e > s);
542
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543#ifdef EBCDIC
544
e050c007 545 PERL_UNUSED_ARG(consider_overlongs);
83dc0f42 546
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547 /* On the EBCDIC code pages we handle, only the native start byte 0xFE can
548 * mean a 32-bit or larger code point (0xFF is an invariant). 0xFE can
549 * also be the start byte for a 31-bit code point; we need at least 2
550 * bytes, and maybe up through 8 bytes, to determine that. (It can also be
551 * the start byte for an overlong sequence, but for 30-bit or smaller code
552 * points, so we don't have to worry about overlongs on EBCDIC.) */
553 if (*s != 0xFE) {
554 return 0;
555 }
83dc0f42 556
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557 if (len == 1) {
558 return -1;
559 }
83dc0f42 560
e050c007 561#else
83dc0f42 562
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563 /* On ASCII, FE and FF are the only start bytes that can evaluate to
564 * needing more than 31 bits. */
565 if (LIKELY(*s < 0xFE)) {
566 return 0;
567 }
83dc0f42 568
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569 /* What we have left are FE and FF. Both of these require more than 31
570 * bits unless they are for overlongs. */
571 if (! consider_overlongs) {
572 return 1;
573 }
83dc0f42 574
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575 /* Here, we have FE or FF. If the input isn't overlong, it evaluates to
576 * above 31 bits. But we need more than one byte to discern this, so if
577 * passed just the start byte, it could be an overlong evaluating to
578 * smaller */
579 if (len == 1) {
580 return -1;
581 }
83dc0f42 582
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583 /* Having excluded len==1, and knowing that FE and FF are both valid start
584 * bytes, we can call the function below to see if the sequence is
585 * overlong. (We don't need the full generality of the called function,
586 * but for these huge code points, speed shouldn't be a consideration, and
587 * the compiler does have enough information, since it's static to this
588 * file, to optimize to just the needed parts.) */
589 is_overlong = is_utf8_overlong_given_start_byte_ok(s, len);
83dc0f42 590
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591 /* If it isn't overlong, more than 31 bits are required. */
592 if (is_overlong == 0) {
593 return 1;
594 }
83dc0f42 595
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596 /* If it is indeterminate if it is overlong, return that */
597 if (is_overlong < 0) {
598 return -1;
599 }
600
601 /* Here is overlong. Such a sequence starting with FE is below 31 bits, as
602 * the max it can be is 2**31 - 1 */
603 if (*s == 0xFE) {
604 return 0;
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605 }
606
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607#endif
608
609 /* Here, ASCII and EBCDIC rejoin:
610 * On ASCII: We have an overlong sequence starting with FF
611 * On EBCDIC: We have a sequence starting with FE. */
612
613 { /* For C89, use a block so the declaration can be close to its use */
614
615#ifdef EBCDIC
616
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617 /* U+7FFFFFFF (2 ** 31 - 1)
618 * [0] [1] [2] [3] [4] [5] [6] [7] [8] [9] 10 11 12 13
619 * IBM-1047: \xFE\x41\x41\x41\x41\x41\x41\x42\x73\x73\x73\x73\x73\x73
620 * IBM-037: \xFE\x41\x41\x41\x41\x41\x41\x42\x72\x72\x72\x72\x72\x72
621 * POSIX-BC: \xFE\x41\x41\x41\x41\x41\x41\x42\x75\x75\x75\x75\x75\x75
622 * I8: \xFF\xA0\xA0\xA0\xA0\xA0\xA0\xA1\xBF\xBF\xBF\xBF\xBF\xBF
623 * U+80000000 (2 ** 31):
624 * IBM-1047: \xFE\x41\x41\x41\x41\x41\x41\x43\x41\x41\x41\x41\x41\x41
625 * IBM-037: \xFE\x41\x41\x41\x41\x41\x41\x43\x41\x41\x41\x41\x41\x41
626 * POSIX-BC: \xFE\x41\x41\x41\x41\x41\x41\x43\x41\x41\x41\x41\x41\x41
627 * I8: \xFF\xA0\xA0\xA0\xA0\xA0\xA0\xA2\xA0\xA0\xA0\xA0\xA0\xA0
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628 *
629 * and since we know that *s = \xfe, any continuation sequcence
630 * following it that is gt the below is above 31 bits
631 [0] [1] [2] [3] [4] [5] [6] */
632 const U8 conts_for_highest_30_bit[] = "\x41\x41\x41\x41\x41\x41\x42";
633
634#else
635
636 /* FF overlong for U+7FFFFFFF (2 ** 31 - 1)
637 * ASCII: \xFF\x80\x80\x80\x80\x80\x80\x81\xBF\xBF\xBF\xBF\xBF
638 * FF overlong for U+80000000 (2 ** 31):
639 * ASCII: \xFF\x80\x80\x80\x80\x80\x80\x82\x80\x80\x80\x80\x80
640 * and since we know that *s = \xff, any continuation sequcence
641 * following it that is gt the below is above 30 bits
642 [0] [1] [2] [3] [4] [5] [6] */
643 const U8 conts_for_highest_30_bit[] = "\x80\x80\x80\x80\x80\x80\x81";
5f995336 644
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645
646#endif
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647 const STRLEN conts_len = sizeof(conts_for_highest_30_bit) - 1;
648 const STRLEN cmp_len = MIN(conts_len, len - 1);
649
650 /* Now compare the continuation bytes in s with the ones we have
651 * compiled in that are for the largest 30 bit code point. If we have
652 * enough bytes available to determine the answer, or the bytes we do
653 * have differ from them, we can compare the two to get a definitive
654 * answer (Note that in UTF-EBCDIC, the two lowest possible
655 * continuation bytes are \x41 and \x42.) */
656 if (cmp_len >= conts_len || memNE(s + 1,
657 conts_for_highest_30_bit,
658 cmp_len))
659 {
660 return cBOOL(memGT(s + 1, conts_for_highest_30_bit, cmp_len));
661 }
83dc0f42 662
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663 /* Here, all the bytes we have are the same as the highest 30-bit code
664 * point, but we are missing so many bytes that we can't make the
665 * determination */
666 return -1;
667 }
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668}
669
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670#endif
671
d6be65ae 672PERL_STATIC_INLINE int
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673S_is_utf8_overlong_given_start_byte_ok(const U8 * const s, const STRLEN len)
674{
d6be65ae
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675 /* Returns an int indicating whether or not the UTF-8 sequence from 's' to
676 * 's' + 'len' - 1 is an overlong. It returns 1 if it is an overlong; 0 if
677 * it isn't, and -1 if there isn't enough information to tell. This last
678 * return value can happen if the sequence is incomplete, missing some
679 * trailing bytes that would form a complete character. If there are
680 * enough bytes to make a definitive decision, this function does so.
681 * Usually 2 bytes sufficient.
682 *
683 * Overlongs can occur whenever the number of continuation bytes changes.
684 * That means whenever the number of leading 1 bits in a start byte
685 * increases from the next lower start byte. That happens for start bytes
686 * C0, E0, F0, F8, FC, FE, and FF. On modern perls, the following illegal
687 * start bytes have already been excluded, so don't need to be tested here;
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688 * ASCII platforms: C0, C1
689 * EBCDIC platforms C0, C1, C2, C3, C4, E0
d6be65ae 690 */
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691
692 const U8 s0 = NATIVE_UTF8_TO_I8(s[0]);
693 const U8 s1 = NATIVE_UTF8_TO_I8(s[1]);
694
695 PERL_ARGS_ASSERT_IS_UTF8_OVERLONG_GIVEN_START_BYTE_OK;
696 assert(len > 1 && UTF8_IS_START(*s));
697
698 /* Each platform has overlongs after the start bytes given above (expressed
699 * in I8 for EBCDIC). What constitutes an overlong varies by platform, but
700 * the logic is the same, except the E0 overlong has already been excluded
701 * on EBCDIC platforms. The values below were found by manually
702 * inspecting the UTF-8 patterns. See the tables in utf8.h and
703 * utfebcdic.h. */
704
705# ifdef EBCDIC
706# define F0_ABOVE_OVERLONG 0xB0
707# define F8_ABOVE_OVERLONG 0xA8
708# define FC_ABOVE_OVERLONG 0xA4
709# define FE_ABOVE_OVERLONG 0xA2
710# define FF_OVERLONG_PREFIX "\xfe\x41\x41\x41\x41\x41\x41\x41"
711 /* I8(0xfe) is FF */
712# else
713
714 if (s0 == 0xE0 && UNLIKELY(s1 < 0xA0)) {
d6be65ae 715 return 1;
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716 }
717
718# define F0_ABOVE_OVERLONG 0x90
719# define F8_ABOVE_OVERLONG 0x88
720# define FC_ABOVE_OVERLONG 0x84
721# define FE_ABOVE_OVERLONG 0x82
722# define FF_OVERLONG_PREFIX "\xff\x80\x80\x80\x80\x80\x80"
723# endif
724
725
726 if ( (s0 == 0xF0 && UNLIKELY(s1 < F0_ABOVE_OVERLONG))
727 || (s0 == 0xF8 && UNLIKELY(s1 < F8_ABOVE_OVERLONG))
728 || (s0 == 0xFC && UNLIKELY(s1 < FC_ABOVE_OVERLONG))
729 || (s0 == 0xFE && UNLIKELY(s1 < FE_ABOVE_OVERLONG)))
730 {
d6be65ae 731 return 1;
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732 }
733
b0b342d4 734 /* Check for the FF overlong */
d6be65ae 735 return isFF_OVERLONG(s, len);
b0b342d4
KW
736}
737
8d6204cc 738PERL_STATIC_INLINE int
b0b342d4
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739S_isFF_OVERLONG(const U8 * const s, const STRLEN len)
740{
8d6204cc
KW
741 /* Returns an int indicating whether or not the UTF-8 sequence from 's' to
742 * 'e' - 1 is an overlong beginning with \xFF. It returns 1 if it is; 0 if
743 * it isn't, and -1 if there isn't enough information to tell. This last
744 * return value can happen if the sequence is incomplete, missing some
745 * trailing bytes that would form a complete character. If there are
746 * enough bytes to make a definitive decision, this function does so. */
747
b0b342d4 748 PERL_ARGS_ASSERT_ISFF_OVERLONG;
12a4bed3 749
8d6204cc
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750 /* To be an FF overlong, all the available bytes must match */
751 if (LIKELY(memNE(s, FF_OVERLONG_PREFIX,
752 MIN(len, sizeof(FF_OVERLONG_PREFIX) - 1))))
753 {
754 return 0;
755 }
756
757 /* To be an FF overlong sequence, all the bytes in FF_OVERLONG_PREFIX must
758 * be there; what comes after them doesn't matter. See tables in utf8.h,
b0b342d4 759 * utfebcdic.h. */
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760 if (len >= sizeof(FF_OVERLONG_PREFIX) - 1) {
761 return 1;
762 }
12a4bed3 763
8d6204cc
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764 /* The missing bytes could cause the result to go one way or the other, so
765 * the result is indeterminate */
766 return -1;
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767}
768
d22ec717 769#if defined(UV_IS_QUAD) /* These assume IV_MAX is 2**63-1 */
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770# ifdef EBCDIC /* Actually is I8 */
771# define HIGHEST_REPRESENTABLE_UTF8 \
d22ec717 772 "\xFF\xA7\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF"
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773# else
774# define HIGHEST_REPRESENTABLE_UTF8 \
d22ec717 775 "\xFF\x80\x87\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF"
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776# endif
777#endif
778
c285bbc4 779PERL_STATIC_INLINE int
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780S_does_utf8_overflow(const U8 * const s,
781 const U8 * e,
782 const bool consider_overlongs)
a77c906e 783{
c285bbc4 784 /* Returns an int indicating whether or not the UTF-8 sequence from 's' to
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785 * 'e' - 1 would overflow an IV on this platform; that is if it represents
786 * a code point larger than the highest representable code point. It
787 * returns 1 if it does overflow; 0 if it doesn't, and -1 if there isn't
788 * enough information to tell. This last return value can happen if the
789 * sequence is incomplete, missing some trailing bytes that would form a
790 * complete character. If there are enough bytes to make a definitive
791 * decision, this function does so.
c285bbc4 792 *
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793 * If 'consider_overlongs' is TRUE, the function checks for the possibility
794 * that the sequence is an overlong that doesn't overflow. Otherwise, it
795 * assumes the sequence is not an overlong. This can give different
796 * results only on ASCII 32-bit platforms.
797 *
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798 * (For ASCII platforms, we could use memcmp() because we don't have to
799 * convert each byte to I8, but it's very rare input indeed that would
800 * approach overflow, so the loop below will likely only get executed once.)
801 *
802 * 'e' - 1 must not be beyond a full character. */
a77c906e 803
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804
805 PERL_ARGS_ASSERT_DOES_UTF8_OVERFLOW;
806 assert(s <= e && s + UTF8SKIP(s) >= e);
807
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808#if ! defined(UV_IS_QUAD)
809
810 return is_utf8_cp_above_31_bits(s, e, consider_overlongs);
811
812#else
813
814 PERL_UNUSED_ARG(consider_overlongs);
815
816 {
817 const STRLEN len = e - s;
818 const U8 *x;
819 const U8 * y = (const U8 *) HIGHEST_REPRESENTABLE_UTF8;
820
821 for (x = s; x < e; x++, y++) {
822
823 if (UNLIKELY(NATIVE_UTF8_TO_I8(*x) == *y)) {
824 continue;
825 }
826
827 /* If this byte is larger than the corresponding highest UTF-8
828 * byte, the sequence overflow; otherwise the byte is less than,
829 * and so the sequence doesn't overflow */
830 return NATIVE_UTF8_TO_I8(*x) > *y;
831
832 }
833
834 /* Got to the end and all bytes are the same. If the input is a whole
835 * character, it doesn't overflow. And if it is a partial character,
836 * there's not enough information to tell */
837 if (len < sizeof(HIGHEST_REPRESENTABLE_UTF8) - 1) {
838 return -1;
839 }
840
841 return 0;
842 }
843
844#endif
845
846}
847
848#if 0
849
850/* This is the portions of the above function that deal with UV_MAX instead of
851 * IV_MAX. They are left here in case we want to combine them so that internal
852 * uses can have larger code points. The only logic difference is that the
853 * 32-bit EBCDIC platform is treate like the 64-bit, and the 32-bit ASCII has
854 * different logic.
855 */
856
857/* Anything larger than this will overflow the word if it were converted into a UV */
858#if defined(UV_IS_QUAD)
859# ifdef EBCDIC /* Actually is I8 */
860# define HIGHEST_REPRESENTABLE_UTF8 \
861 "\xFF\xAF\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF"
862# else
863# define HIGHEST_REPRESENTABLE_UTF8 \
864 "\xFF\x80\x8F\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF"
865# endif
866#else /* 32-bit */
867# ifdef EBCDIC
868# define HIGHEST_REPRESENTABLE_UTF8 \
869 "\xFF\xA0\xA0\xA0\xA0\xA0\xA0\xA3\xBF\xBF\xBF\xBF\xBF\xBF"
870# else
871# define HIGHEST_REPRESENTABLE_UTF8 "\xFE\x83\xBF\xBF\xBF\xBF\xBF"
872# endif
873#endif
874
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875#if ! defined(UV_IS_QUAD) && ! defined(EBCDIC)
876
877 /* On 32 bit ASCII machines, many overlongs that start with FF don't
878 * overflow */
e050c007 879 if (consider_overlongs && isFF_OVERLONG(s, len) > 0) {
c285bbc4
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880
881 /* To be such an overlong, the first bytes of 's' must match
882 * FF_OVERLONG_PREFIX, which is "\xff\x80\x80\x80\x80\x80\x80". If we
883 * don't have any additional bytes available, the sequence, when
884 * completed might or might not fit in 32 bits. But if we have that
885 * next byte, we can tell for sure. If it is <= 0x83, then it does
886 * fit. */
887 if (len <= sizeof(FF_OVERLONG_PREFIX) - 1) {
888 return -1;
889 }
890
891 return s[sizeof(FF_OVERLONG_PREFIX) - 1] > 0x83;
a77c906e
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892 }
893
d22ec717
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894/* Starting with the #else, the rest of the function is identical except
895 * 1. we need to move the 'len' declaration to be global to the function
896 * 2. the endif move to just after the UNUSED_ARG.
897 * An empty endif is given just below to satisfy the preprocessor
898 */
a77c906e
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899#endif
900
d22ec717 901#endif
a77c906e 902
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903#undef F0_ABOVE_OVERLONG
904#undef F8_ABOVE_OVERLONG
905#undef FC_ABOVE_OVERLONG
906#undef FE_ABOVE_OVERLONG
907#undef FF_OVERLONG_PREFIX
908
35f8c9bd 909STRLEN
edc2c47a 910Perl__is_utf8_char_helper(const U8 * const s, const U8 * e, const U32 flags)
35f8c9bd 911{
2b479609 912 STRLEN len;
12a4bed3 913 const U8 *x;
35f8c9bd 914
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915 /* A helper function that should not be called directly.
916 *
917 * This function returns non-zero if the string beginning at 's' and
918 * looking no further than 'e - 1' is well-formed Perl-extended-UTF-8 for a
919 * code point; otherwise it returns 0. The examination stops after the
920 * first code point in 's' is validated, not looking at the rest of the
921 * input. If 'e' is such that there are not enough bytes to represent a
922 * complete code point, this function will return non-zero anyway, if the
923 * bytes it does have are well-formed UTF-8 as far as they go, and aren't
924 * excluded by 'flags'.
925 *
926 * A non-zero return gives the number of bytes required to represent the
927 * code point. Be aware that if the input is for a partial character, the
928 * return will be larger than 'e - s'.
929 *
930 * This function assumes that the code point represented is UTF-8 variant.
56576a04
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931 * The caller should have excluded the possibility of it being invariant
932 * before calling this function.
2b479609
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933 *
934 * 'flags' can be 0, or any combination of the UTF8_DISALLOW_foo flags
935 * accepted by L</utf8n_to_uvchr>. If non-zero, this function will return
936 * 0 if the code point represented is well-formed Perl-extended-UTF-8, but
937 * disallowed by the flags. If the input is only for a partial character,
938 * the function will return non-zero if there is any sequence of
939 * well-formed UTF-8 that, when appended to the input sequence, could
940 * result in an allowed code point; otherwise it returns 0. Non characters
941 * cannot be determined based on partial character input. But many of the
942 * other excluded types can be determined with just the first one or two
943 * bytes.
944 *
945 */
946
947 PERL_ARGS_ASSERT__IS_UTF8_CHAR_HELPER;
948
949 assert(0 == (flags & ~(UTF8_DISALLOW_ILLEGAL_INTERCHANGE
d044b7a7 950 |UTF8_DISALLOW_PERL_EXTENDED)));
2b479609 951 assert(! UTF8_IS_INVARIANT(*s));
35f8c9bd 952
2b479609 953 /* A variant char must begin with a start byte */
35f8c9bd
KW
954 if (UNLIKELY(! UTF8_IS_START(*s))) {
955 return 0;
956 }
957
edc2c47a
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958 /* Examine a maximum of a single whole code point */
959 if (e - s > UTF8SKIP(s)) {
960 e = s + UTF8SKIP(s);
961 }
962
2b479609
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963 len = e - s;
964
965 if (flags && isUTF8_POSSIBLY_PROBLEMATIC(*s)) {
966 const U8 s0 = NATIVE_UTF8_TO_I8(s[0]);
35f8c9bd 967
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968 /* Here, we are disallowing some set of largish code points, and the
969 * first byte indicates the sequence is for a code point that could be
970 * in the excluded set. We generally don't have to look beyond this or
971 * the second byte to see if the sequence is actually for one of the
972 * excluded classes. The code below is derived from this table:
973 *
2b479609
KW
974 * UTF-8 UTF-EBCDIC I8
975 * U+D800: \xED\xA0\x80 \xF1\xB6\xA0\xA0 First surrogate
976 * U+DFFF: \xED\xBF\xBF \xF1\xB7\xBF\xBF Final surrogate
977 * U+110000: \xF4\x90\x80\x80 \xF9\xA2\xA0\xA0\xA0 First above Unicode
978 *
56576a04
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979 * Keep in mind that legal continuation bytes range between \x80..\xBF
980 * for UTF-8, and \xA0..\xBF for I8. Anything above those aren't
981 * continuation bytes. Hence, we don't have to test the upper edge
982 * because if any of those is encountered, the sequence is malformed,
983 * and would fail elsewhere in this function.
984 *
985 * The code here likewise assumes that there aren't other
986 * malformations; again the function should fail elsewhere because of
987 * these. For example, an overlong beginning with FC doesn't actually
988 * have to be a super; it could actually represent a small code point,
989 * even U+0000. But, since overlongs (and other malformations) are
990 * illegal, the function should return FALSE in either case.
2b479609
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991 */
992
993#ifdef EBCDIC /* On EBCDIC, these are actually I8 bytes */
994# define FIRST_START_BYTE_THAT_IS_DEFINITELY_SUPER 0xFA
19794540 995# define IS_UTF8_2_BYTE_SUPER(s0, s1) ((s0) == 0xF9 && (s1) >= 0xA2)
2b479609 996
19794540
KW
997# define IS_UTF8_2_BYTE_SURROGATE(s0, s1) ((s0) == 0xF1 \
998 /* B6 and B7 */ \
999 && ((s1) & 0xFE ) == 0xB6)
57ff5f59 1000# define isUTF8_PERL_EXTENDED(s) (*s == I8_TO_NATIVE_UTF8(0xFF))
2b479609
KW
1001#else
1002# define FIRST_START_BYTE_THAT_IS_DEFINITELY_SUPER 0xF5
19794540
KW
1003# define IS_UTF8_2_BYTE_SUPER(s0, s1) ((s0) == 0xF4 && (s1) >= 0x90)
1004# define IS_UTF8_2_BYTE_SURROGATE(s0, s1) ((s0) == 0xED && (s1) >= 0xA0)
57ff5f59 1005# define isUTF8_PERL_EXTENDED(s) (*s >= 0xFE)
2b479609
KW
1006#endif
1007
1008 if ( (flags & UTF8_DISALLOW_SUPER)
ddb65933
KW
1009 && UNLIKELY(s0 >= FIRST_START_BYTE_THAT_IS_DEFINITELY_SUPER))
1010 {
2b479609
KW
1011 return 0; /* Above Unicode */
1012 }
1013
d044b7a7 1014 if ( (flags & UTF8_DISALLOW_PERL_EXTENDED)
57ff5f59 1015 && UNLIKELY(isUTF8_PERL_EXTENDED(s)))
2b479609 1016 {
57ff5f59 1017 return 0;
2b479609
KW
1018 }
1019
1020 if (len > 1) {
1021 const U8 s1 = NATIVE_UTF8_TO_I8(s[1]);
1022
1023 if ( (flags & UTF8_DISALLOW_SUPER)
19794540 1024 && UNLIKELY(IS_UTF8_2_BYTE_SUPER(s0, s1)))
2b479609
KW
1025 {
1026 return 0; /* Above Unicode */
1027 }
1028
1029 if ( (flags & UTF8_DISALLOW_SURROGATE)
19794540 1030 && UNLIKELY(IS_UTF8_2_BYTE_SURROGATE(s0, s1)))
2b479609
KW
1031 {
1032 return 0; /* Surrogate */
1033 }
1034
1035 if ( (flags & UTF8_DISALLOW_NONCHAR)
1036 && UNLIKELY(UTF8_IS_NONCHAR(s, e)))
1037 {
1038 return 0; /* Noncharacter code point */
1039 }
1040 }
1041 }
1042
1043 /* Make sure that all that follows are continuation bytes */
35f8c9bd
KW
1044 for (x = s + 1; x < e; x++) {
1045 if (UNLIKELY(! UTF8_IS_CONTINUATION(*x))) {
1046 return 0;
1047 }
1048 }
1049
af13dd8a 1050 /* Here is syntactically valid. Next, make sure this isn't the start of an
12a4bed3 1051 * overlong. */
d6be65ae 1052 if (len > 1 && is_utf8_overlong_given_start_byte_ok(s, len) > 0) {
12a4bed3 1053 return 0;
af13dd8a
KW
1054 }
1055
12a4bed3
KW
1056 /* And finally, that the code point represented fits in a word on this
1057 * platform */
e050c007
KW
1058 if (0 < does_utf8_overflow(s, e,
1059 0 /* Don't consider overlongs */
1060 ))
1061 {
12a4bed3 1062 return 0;
35f8c9bd
KW
1063 }
1064
2b479609 1065 return UTF8SKIP(s);
35f8c9bd
KW
1066}
1067
7e2f38b2 1068char *
63ab03b3 1069Perl__byte_dump_string(pTHX_ const U8 * const start, const STRLEN len, const bool format)
7cf8d05d
KW
1070{
1071 /* Returns a mortalized C string that is a displayable copy of the 'len'
63ab03b3 1072 * bytes starting at 'start'. 'format' gives how to display each byte.
7e2f38b2
KW
1073 * Currently, there are only two formats, so it is currently a bool:
1074 * 0 \xab
1075 * 1 ab (that is a space between two hex digit bytes)
1076 */
7cf8d05d
KW
1077
1078 const STRLEN output_len = 4 * len + 1; /* 4 bytes per each input, plus a
1079 trailing NUL */
63ab03b3
KW
1080 const U8 * s = start;
1081 const U8 * const e = start + len;
7cf8d05d
KW
1082 char * output;
1083 char * d;
1084
1085 PERL_ARGS_ASSERT__BYTE_DUMP_STRING;
1086
1087 Newx(output, output_len, char);
1088 SAVEFREEPV(output);
1089
1090 d = output;
63ab03b3 1091 for (s = start; s < e; s++) {
7cf8d05d
KW
1092 const unsigned high_nibble = (*s & 0xF0) >> 4;
1093 const unsigned low_nibble = (*s & 0x0F);
1094
7e2f38b2 1095 if (format) {
63ab03b3
KW
1096 if (s > start) {
1097 *d++ = ' ';
1098 }
7e2f38b2
KW
1099 }
1100 else {
1101 *d++ = '\\';
1102 *d++ = 'x';
1103 }
7cf8d05d
KW
1104
1105 if (high_nibble < 10) {
1106 *d++ = high_nibble + '0';
1107 }
1108 else {
1109 *d++ = high_nibble - 10 + 'a';
1110 }
1111
1112 if (low_nibble < 10) {
1113 *d++ = low_nibble + '0';
1114 }
1115 else {
1116 *d++ = low_nibble - 10 + 'a';
1117 }
1118 }
1119
1120 *d = '\0';
1121 return output;
1122}
1123
806547a7 1124PERL_STATIC_INLINE char *
7cf8d05d
KW
1125S_unexpected_non_continuation_text(pTHX_ const U8 * const s,
1126
421da25c 1127 /* Max number of bytes to print */
3cc6a05e 1128 STRLEN print_len,
7cf8d05d
KW
1129
1130 /* Which one is the non-continuation */
1131 const STRLEN non_cont_byte_pos,
1132
1133 /* How many bytes should there be? */
1134 const STRLEN expect_len)
806547a7
KW
1135{
1136 /* Return the malformation warning text for an unexpected continuation
1137 * byte. */
1138
7cf8d05d 1139 const char * const where = (non_cont_byte_pos == 1)
806547a7 1140 ? "immediately"
7cf8d05d
KW
1141 : Perl_form(aTHX_ "%d bytes",
1142 (int) non_cont_byte_pos);
421da25c
KW
1143 const U8 * x = s + non_cont_byte_pos;
1144 const U8 * e = s + print_len;
806547a7
KW
1145
1146 PERL_ARGS_ASSERT_UNEXPECTED_NON_CONTINUATION_TEXT;
1147
7cf8d05d
KW
1148 /* We don't need to pass this parameter, but since it has already been
1149 * calculated, it's likely faster to pass it; verify under DEBUGGING */
1150 assert(expect_len == UTF8SKIP(s));
1151
421da25c
KW
1152 /* As a defensive coding measure, don't output anything past a NUL. Such
1153 * bytes shouldn't be in the middle of a malformation, and could mark the
1154 * end of the allocated string, and what comes after is undefined */
1155 for (; x < e; x++) {
1156 if (*x == '\0') {
1157 x++; /* Output this particular NUL */
1158 break;
1159 }
1160 }
1161
7cf8d05d
KW
1162 return Perl_form(aTHX_ "%s: %s (unexpected non-continuation byte 0x%02x,"
1163 " %s after start byte 0x%02x; need %d bytes, got %d)",
1164 malformed_text,
421da25c 1165 _byte_dump_string(s, x - s, 0),
7cf8d05d
KW
1166 *(s + non_cont_byte_pos),
1167 where,
1168 *s,
1169 (int) expect_len,
1170 (int) non_cont_byte_pos);
806547a7
KW
1171}
1172
35f8c9bd
KW
1173/*
1174
de69f3af 1175=for apidoc utf8n_to_uvchr
378516de
KW
1176
1177THIS FUNCTION SHOULD BE USED IN ONLY VERY SPECIALIZED CIRCUMSTANCES.
de69f3af 1178Most code should use L</utf8_to_uvchr_buf>() rather than call this directly.
67e989fb 1179
9041c2e3 1180Bottom level UTF-8 decode routine.
de69f3af 1181Returns the native code point value of the first character in the string C<s>,
746afd53
KW
1182which is assumed to be in UTF-8 (or UTF-EBCDIC) encoding, and no longer than
1183C<curlen> bytes; C<*retlen> (if C<retlen> isn't NULL) will be set to
1184the length, in bytes, of that character.
949cf498
KW
1185
1186The value of C<flags> determines the behavior when C<s> does not point to a
2b5e7bc2
KW
1187well-formed UTF-8 character. If C<flags> is 0, encountering a malformation
1188causes zero to be returned and C<*retlen> is set so that (S<C<s> + C<*retlen>>)
1189is the next possible position in C<s> that could begin a non-malformed
1190character. Also, if UTF-8 warnings haven't been lexically disabled, a warning
1191is raised. Some UTF-8 input sequences may contain multiple malformations.
1192This function tries to find every possible one in each call, so multiple
56576a04 1193warnings can be raised for the same sequence.
949cf498
KW
1194
1195Various ALLOW flags can be set in C<flags> to allow (and not warn on)
1196individual types of malformations, such as the sequence being overlong (that
1197is, when there is a shorter sequence that can express the same code point;
1198overlong sequences are expressly forbidden in the UTF-8 standard due to
1199potential security issues). Another malformation example is the first byte of
1200a character not being a legal first byte. See F<utf8.h> for the list of such
94953955
KW
1201flags. Even if allowed, this function generally returns the Unicode
1202REPLACEMENT CHARACTER when it encounters a malformation. There are flags in
1203F<utf8.h> to override this behavior for the overlong malformations, but don't
1204do that except for very specialized purposes.
949cf498 1205
796b6530 1206The C<UTF8_CHECK_ONLY> flag overrides the behavior when a non-allowed (by other
949cf498
KW
1207flags) malformation is found. If this flag is set, the routine assumes that
1208the caller will raise a warning, and this function will silently just set
d088425d
KW
1209C<retlen> to C<-1> (cast to C<STRLEN>) and return zero.
1210
75200dff 1211Note that this API requires disambiguation between successful decoding a C<NUL>
796b6530 1212character, and an error return (unless the C<UTF8_CHECK_ONLY> flag is set), as
111fa700
KW
1213in both cases, 0 is returned, and, depending on the malformation, C<retlen> may
1214be set to 1. To disambiguate, upon a zero return, see if the first byte of
1215C<s> is 0 as well. If so, the input was a C<NUL>; if not, the input had an
f9380377 1216error. Or you can use C<L</utf8n_to_uvchr_error>>.
949cf498
KW
1217
1218Certain code points are considered problematic. These are Unicode surrogates,
746afd53 1219Unicode non-characters, and code points above the Unicode maximum of 0x10FFFF.
949cf498 1220By default these are considered regular code points, but certain situations
ecc1615f
KW
1221warrant special handling for them, which can be specified using the C<flags>
1222parameter. If C<flags> contains C<UTF8_DISALLOW_ILLEGAL_INTERCHANGE>, all
1223three classes are treated as malformations and handled as such. The flags
1224C<UTF8_DISALLOW_SURROGATE>, C<UTF8_DISALLOW_NONCHAR>, and
1225C<UTF8_DISALLOW_SUPER> (meaning above the legal Unicode maximum) can be set to
1226disallow these categories individually. C<UTF8_DISALLOW_ILLEGAL_INTERCHANGE>
1227restricts the allowed inputs to the strict UTF-8 traditionally defined by
1228Unicode. Use C<UTF8_DISALLOW_ILLEGAL_C9_INTERCHANGE> to use the strictness
1229definition given by
1230L<Unicode Corrigendum #9|http://www.unicode.org/versions/corrigendum9.html>.
1231The difference between traditional strictness and C9 strictness is that the
1232latter does not forbid non-character code points. (They are still discouraged,
1233however.) For more discussion see L<perlunicode/Noncharacter code points>.
1234
1235The flags C<UTF8_WARN_ILLEGAL_INTERCHANGE>,
1236C<UTF8_WARN_ILLEGAL_C9_INTERCHANGE>, C<UTF8_WARN_SURROGATE>,
796b6530
KW
1237C<UTF8_WARN_NONCHAR>, and C<UTF8_WARN_SUPER> will cause warning messages to be
1238raised for their respective categories, but otherwise the code points are
1239considered valid (not malformations). To get a category to both be treated as
1240a malformation and raise a warning, specify both the WARN and DISALLOW flags.
949cf498 1241(But note that warnings are not raised if lexically disabled nor if
796b6530 1242C<UTF8_CHECK_ONLY> is also specified.)
949cf498 1243
57ff5f59
KW
1244Extremely high code points were never specified in any standard, and require an
1245extension to UTF-8 to express, which Perl does. It is likely that programs
1246written in something other than Perl would not be able to read files that
1247contain these; nor would Perl understand files written by something that uses a
1248different extension. For these reasons, there is a separate set of flags that
1249can warn and/or disallow these extremely high code points, even if other
1250above-Unicode ones are accepted. They are the C<UTF8_WARN_PERL_EXTENDED> and
1251C<UTF8_DISALLOW_PERL_EXTENDED> flags. For more information see
1252L</C<UTF8_GOT_PERL_EXTENDED>>. Of course C<UTF8_DISALLOW_SUPER> will treat all
1253above-Unicode code points, including these, as malformations.
1254(Note that the Unicode standard considers anything above 0x10FFFF to be
1255illegal, but there are standards predating it that allow up to 0x7FFF_FFFF
1256(2**31 -1))
1257
1258A somewhat misleadingly named synonym for C<UTF8_WARN_PERL_EXTENDED> is
1259retained for backward compatibility: C<UTF8_WARN_ABOVE_31_BIT>. Similarly,
1260C<UTF8_DISALLOW_ABOVE_31_BIT> is usable instead of the more accurately named
1261C<UTF8_DISALLOW_PERL_EXTENDED>. The names are misleading because these flags
1262can apply to code points that actually do fit in 31 bits. This happens on
1263EBCDIC platforms, and sometimes when the L<overlong
1264malformation|/C<UTF8_GOT_LONG>> is also present. The new names accurately
1265describe the situation in all cases.
1266
ab8e6d41 1267
949cf498
KW
1268All other code points corresponding to Unicode characters, including private
1269use and those yet to be assigned, are never considered malformed and never
1270warn.
67e989fb 1271
37607a96 1272=cut
f9380377
KW
1273
1274Also implemented as a macro in utf8.h
1275*/
1276
1277UV
e6a4ffc3
KW
1278Perl_utf8n_to_uvchr(const U8 *s,
1279 STRLEN curlen,
1280 STRLEN *retlen,
1281 const U32 flags)
f9380377
KW
1282{
1283 PERL_ARGS_ASSERT_UTF8N_TO_UVCHR;
1284
1285 return utf8n_to_uvchr_error(s, curlen, retlen, flags, NULL);
1286}
1287
1288/*
1289
1290=for apidoc utf8n_to_uvchr_error
1291
1292THIS FUNCTION SHOULD BE USED IN ONLY VERY SPECIALIZED CIRCUMSTANCES.
1293Most code should use L</utf8_to_uvchr_buf>() rather than call this directly.
1294
1295This function is for code that needs to know what the precise malformation(s)
37657a5b
KW
1296are when an error is found. If you also need to know the generated warning
1297messages, use L</utf8n_to_uvchr_msgs>() instead.
f9380377
KW
1298
1299It is like C<L</utf8n_to_uvchr>> but it takes an extra parameter placed after
1300all the others, C<errors>. If this parameter is 0, this function behaves
1301identically to C<L</utf8n_to_uvchr>>. Otherwise, C<errors> should be a pointer
1302to a C<U32> variable, which this function sets to indicate any errors found.
1303Upon return, if C<*errors> is 0, there were no errors found. Otherwise,
1304C<*errors> is the bit-wise C<OR> of the bits described in the list below. Some
1305of these bits will be set if a malformation is found, even if the input
7a65503b 1306C<flags> parameter indicates that the given malformation is allowed; those
f9380377
KW
1307exceptions are noted:
1308
1309=over 4
1310
57ff5f59 1311=item C<UTF8_GOT_PERL_EXTENDED>
f9380377 1312
57ff5f59
KW
1313The input sequence is not standard UTF-8, but a Perl extension. This bit is
1314set only if the input C<flags> parameter contains either the
1315C<UTF8_DISALLOW_PERL_EXTENDED> or the C<UTF8_WARN_PERL_EXTENDED> flags.
1316
1317Code points above 0x7FFF_FFFF (2**31 - 1) were never specified in any standard,
1318and so some extension must be used to express them. Perl uses a natural
1319extension to UTF-8 to represent the ones up to 2**36-1, and invented a further
1320extension to represent even higher ones, so that any code point that fits in a
132164-bit word can be represented. Text using these extensions is not likely to
1322be portable to non-Perl code. We lump both of these extensions together and
1323refer to them as Perl extended UTF-8. There exist other extensions that people
1324have invented, incompatible with Perl's.
1325
1326On EBCDIC platforms starting in Perl v5.24, the Perl extension for representing
1327extremely high code points kicks in at 0x3FFF_FFFF (2**30 -1), which is lower
1328than on ASCII. Prior to that, code points 2**31 and higher were simply
1329unrepresentable, and a different, incompatible method was used to represent
1330code points between 2**30 and 2**31 - 1.
1331
1332On both platforms, ASCII and EBCDIC, C<UTF8_GOT_PERL_EXTENDED> is set if
1333Perl extended UTF-8 is used.
1334
1335In earlier Perls, this bit was named C<UTF8_GOT_ABOVE_31_BIT>, which you still
1336may use for backward compatibility. That name is misleading, as this flag may
1337be set when the code point actually does fit in 31 bits. This happens on
1338EBCDIC platforms, and sometimes when the L<overlong
1339malformation|/C<UTF8_GOT_LONG>> is also present. The new name accurately
1340describes the situation in all cases.
f9380377
KW
1341
1342=item C<UTF8_GOT_CONTINUATION>
1343
1344The input sequence was malformed in that the first byte was a a UTF-8
1345continuation byte.
1346
1347=item C<UTF8_GOT_EMPTY>
1348
1349The input C<curlen> parameter was 0.
1350
1351=item C<UTF8_GOT_LONG>
1352
1353The input sequence was malformed in that there is some other sequence that
1354evaluates to the same code point, but that sequence is shorter than this one.
1355
fecaf136
KW
1356Until Unicode 3.1, it was legal for programs to accept this malformation, but
1357it was discovered that this created security issues.
1358
f9380377
KW
1359=item C<UTF8_GOT_NONCHAR>
1360
1361The code point represented by the input UTF-8 sequence is for a Unicode
1362non-character code point.
1363This bit is set only if the input C<flags> parameter contains either the
1364C<UTF8_DISALLOW_NONCHAR> or the C<UTF8_WARN_NONCHAR> flags.
1365
1366=item C<UTF8_GOT_NON_CONTINUATION>
1367
1368The input sequence was malformed in that a non-continuation type byte was found
1369in a position where only a continuation type one should be.
1370
1371=item C<UTF8_GOT_OVERFLOW>
1372
1373The input sequence was malformed in that it is for a code point that is not
d22ec717 1374representable in the number of bits available in an IV on the current platform.
f9380377
KW
1375
1376=item C<UTF8_GOT_SHORT>
1377
1378The input sequence was malformed in that C<curlen> is smaller than required for
1379a complete sequence. In other words, the input is for a partial character
1380sequence.
1381
1382=item C<UTF8_GOT_SUPER>
1383
1384The input sequence was malformed in that it is for a non-Unicode code point;
1385that is, one above the legal Unicode maximum.
1386This bit is set only if the input C<flags> parameter contains either the
1387C<UTF8_DISALLOW_SUPER> or the C<UTF8_WARN_SUPER> flags.
1388
1389=item C<UTF8_GOT_SURROGATE>
1390
1391The input sequence was malformed in that it is for a -Unicode UTF-16 surrogate
1392code point.
1393This bit is set only if the input C<flags> parameter contains either the
1394C<UTF8_DISALLOW_SURROGATE> or the C<UTF8_WARN_SURROGATE> flags.
1395
1396=back
1397
133551d8
KW
1398To do your own error handling, call this function with the C<UTF8_CHECK_ONLY>
1399flag to suppress any warnings, and then examine the C<*errors> return.
1400
f9380377 1401=cut
37657a5b
KW
1402
1403Also implemented as a macro in utf8.h
37607a96 1404*/
67e989fb 1405
a0ed51b3 1406UV
e6a4ffc3 1407Perl_utf8n_to_uvchr_error(const U8 *s,
37657a5b
KW
1408 STRLEN curlen,
1409 STRLEN *retlen,
1410 const U32 flags,
1411 U32 * errors)
1412{
1413 PERL_ARGS_ASSERT_UTF8N_TO_UVCHR_ERROR;
1414
1415 return utf8n_to_uvchr_msgs(s, curlen, retlen, flags, errors, NULL);
1416}
1417
1418/*
1419
1420=for apidoc utf8n_to_uvchr_msgs
1421
1422THIS FUNCTION SHOULD BE USED IN ONLY VERY SPECIALIZED CIRCUMSTANCES.
1423Most code should use L</utf8_to_uvchr_buf>() rather than call this directly.
1424
1425This function is for code that needs to know what the precise malformation(s)
1426are when an error is found, and wants the corresponding warning and/or error
1427messages to be returned to the caller rather than be displayed. All messages
1428that would have been displayed if all lexcial warnings are enabled will be
1429returned.
1430
1431It is just like C<L</utf8n_to_uvchr_error>> but it takes an extra parameter
1432placed after all the others, C<msgs>. If this parameter is 0, this function
1433behaves identically to C<L</utf8n_to_uvchr_error>>. Otherwise, C<msgs> should
1434be a pointer to an C<AV *> variable, in which this function creates a new AV to
1435contain any appropriate messages. The elements of the array are ordered so
1436that the first message that would have been displayed is in the 0th element,
1437and so on. Each element is a hash with three key-value pairs, as follows:
1438
1439=over 4
1440
1441=item C<text>
1442
1443The text of the message as a C<SVpv>.
1444
1445=item C<warn_categories>
1446
1447The warning category (or categories) packed into a C<SVuv>.
1448
1449=item C<flag>
1450
1451A single flag bit associated with this message, in a C<SVuv>.
1452The bit corresponds to some bit in the C<*errors> return value,
1453such as C<UTF8_GOT_LONG>.
1454
1455=back
1456
1457It's important to note that specifying this parameter as non-null will cause
1458any warnings this function would otherwise generate to be suppressed, and
1459instead be placed in C<*msgs>. The caller can check the lexical warnings state
1460(or not) when choosing what to do with the returned messages.
1461
1462If the flag C<UTF8_CHECK_ONLY> is passed, no warnings are generated, and hence
1463no AV is created.
1464
1465The caller, of course, is responsible for freeing any returned AV.
1466
1467=cut
1468*/
1469
1470UV
e6a4ffc3 1471Perl__utf8n_to_uvchr_msgs_helper(const U8 *s,
37657a5b
KW
1472 STRLEN curlen,
1473 STRLEN *retlen,
1474 const U32 flags,
1475 U32 * errors,
1476 AV ** msgs)
a0ed51b3 1477{
d4c19fe8 1478 const U8 * const s0 = s;
2b9519f0 1479 const U8 * send = s0 + curlen;
5af9f822
KW
1480 U32 possible_problems; /* A bit is set here for each potential problem
1481 found as we go along */
1482 UV uv;
1483 STRLEN expectlen; /* How long should this sequence be? */
1484 STRLEN avail_len; /* When input is too short, gives what that is */
1485 U32 discard_errors; /* Used to save branches when 'errors' is NULL; this
1486 gets set and discarded */
a0dbb045 1487
2b5e7bc2
KW
1488 /* The below are used only if there is both an overlong malformation and a
1489 * too short one. Otherwise the first two are set to 's0' and 'send', and
1490 * the third not used at all */
5af9f822 1491 U8 * adjusted_s0;
e9f2c446
KW
1492 U8 temp_char_buf[UTF8_MAXBYTES + 1]; /* Used to avoid a Newx in this
1493 routine; see [perl #130921] */
5af9f822 1494 UV uv_so_far;
e6a4ffc3 1495 dTHX;
5af9f822 1496
e6a4ffc3 1497 PERL_ARGS_ASSERT__UTF8N_TO_UVCHR_MSGS_HELPER;
5af9f822
KW
1498
1499 /* Here, is one of: a) malformed; b) a problematic code point (surrogate,
1500 * non-unicode, or nonchar); or c) on ASCII platforms, one of the Hangul
1501 * syllables that the dfa doesn't properly handle. Quickly dispose of the
1502 * final case. */
1503
1504#ifndef EBCDIC
1505
1506 /* Each of the affected Hanguls starts with \xED */
1507
1508 if (is_HANGUL_ED_utf8_safe(s0, send)) {
1509 if (retlen) {
1510 *retlen = 3;
1511 }
1512 if (errors) {
1513 *errors = 0;
1514 }
1515 if (msgs) {
1516 *msgs = NULL;
1517 }
1518
1519 return ((0xED & UTF_START_MASK(3)) << (2 * UTF_ACCUMULATION_SHIFT))
1520 | ((s0[1] & UTF_CONTINUATION_MASK) << UTF_ACCUMULATION_SHIFT)
1521 | (s0[2] & UTF_CONTINUATION_MASK);
1522 }
1523
1524#endif
1525
1526 /* In conjunction with the exhaustive tests that can be enabled in
1527 * APItest/t/utf8_warn_base.pl, this can make sure the dfa does precisely
1528 * what it is intended to do, and that no flaws in it are masked by
1529 * dropping down and executing the code below
1530 assert(! isUTF8_CHAR(s0, send)
1531 || UTF8_IS_SURROGATE(s0, send)
1532 || UTF8_IS_SUPER(s0, send)
1533 || UTF8_IS_NONCHAR(s0,send));
1534 */
1535
1536 s = s0;
1537 uv = *s0;
1538 possible_problems = 0;
1539 expectlen = 0;
1540 avail_len = 0;
1541 discard_errors = 0;
1542 adjusted_s0 = (U8 *) s0;
1543 uv_so_far = 0;
1544
f9380377
KW
1545 if (errors) {
1546 *errors = 0;
1547 }
1548 else {
1549 errors = &discard_errors;
1550 }
a0dbb045 1551
eb83ed87
KW
1552 /* The order of malformation tests here is important. We should consume as
1553 * few bytes as possible in order to not skip any valid character. This is
1554 * required by the Unicode Standard (section 3.9 of Unicode 6.0); see also
1555 * http://unicode.org/reports/tr36 for more discussion as to why. For
1556 * example, once we've done a UTF8SKIP, we can tell the expected number of
1557 * bytes, and could fail right off the bat if the input parameters indicate
1558 * that there are too few available. But it could be that just that first
1559 * byte is garbled, and the intended character occupies fewer bytes. If we
1560 * blindly assumed that the first byte is correct, and skipped based on
1561 * that number, we could skip over a valid input character. So instead, we
1562 * always examine the sequence byte-by-byte.
1563 *
1564 * We also should not consume too few bytes, otherwise someone could inject
1565 * things. For example, an input could be deliberately designed to
1566 * overflow, and if this code bailed out immediately upon discovering that,
e2660c54 1567 * returning to the caller C<*retlen> pointing to the very next byte (one
eb83ed87
KW
1568 * which is actually part of of the overflowing sequence), that could look
1569 * legitimate to the caller, which could discard the initial partial
2b5e7bc2
KW
1570 * sequence and process the rest, inappropriately.
1571 *
1572 * Some possible input sequences are malformed in more than one way. This
1573 * function goes to lengths to try to find all of them. This is necessary
1574 * for correctness, as the inputs may allow one malformation but not
1575 * another, and if we abandon searching for others after finding the
1576 * allowed one, we could allow in something that shouldn't have been.
1577 */
eb83ed87 1578
b5b9af04 1579 if (UNLIKELY(curlen == 0)) {
2b5e7bc2
KW
1580 possible_problems |= UTF8_GOT_EMPTY;
1581 curlen = 0;
5a48568d 1582 uv = UNICODE_REPLACEMENT;
2b5e7bc2 1583 goto ready_to_handle_errors;
0c443dc2
JH
1584 }
1585
eb83ed87
KW
1586 expectlen = UTF8SKIP(s);
1587
1588 /* A well-formed UTF-8 character, as the vast majority of calls to this
1589 * function will be for, has this expected length. For efficiency, set
1590 * things up here to return it. It will be overriden only in those rare
1591 * cases where a malformation is found */
1592 if (retlen) {
1593 *retlen = expectlen;
1594 }
1595
eb83ed87 1596 /* A continuation character can't start a valid sequence */
b5b9af04 1597 if (UNLIKELY(UTF8_IS_CONTINUATION(uv))) {
2b5e7bc2
KW
1598 possible_problems |= UTF8_GOT_CONTINUATION;
1599 curlen = 1;
1600 uv = UNICODE_REPLACEMENT;
1601 goto ready_to_handle_errors;
ba210ebe 1602 }
9041c2e3 1603
dcd27b3c 1604 /* Here is not a continuation byte, nor an invariant. The only thing left
ddb65933
KW
1605 * is a start byte (possibly for an overlong). (We can't use UTF8_IS_START
1606 * because it excludes start bytes like \xC0 that always lead to
1607 * overlongs.) */
dcd27b3c 1608
534752c1
KW
1609 /* Convert to I8 on EBCDIC (no-op on ASCII), then remove the leading bits
1610 * that indicate the number of bytes in the character's whole UTF-8
1611 * sequence, leaving just the bits that are part of the value. */
1612 uv = NATIVE_UTF8_TO_I8(uv) & UTF_START_MASK(expectlen);
ba210ebe 1613
e308b348
KW
1614 /* Setup the loop end point, making sure to not look past the end of the
1615 * input string, and flag it as too short if the size isn't big enough. */
e308b348
KW
1616 if (UNLIKELY(curlen < expectlen)) {
1617 possible_problems |= UTF8_GOT_SHORT;
1618 avail_len = curlen;
e308b348
KW
1619 }
1620 else {
2b9519f0 1621 send = (U8*) s0 + expectlen;
e308b348 1622 }
e308b348 1623
eb83ed87 1624 /* Now, loop through the remaining bytes in the character's sequence,
e308b348 1625 * accumulating each into the working value as we go. */
eb83ed87 1626 for (s = s0 + 1; s < send; s++) {
b5b9af04 1627 if (LIKELY(UTF8_IS_CONTINUATION(*s))) {
8850bf83 1628 uv = UTF8_ACCUMULATE(uv, *s);
2b5e7bc2
KW
1629 continue;
1630 }
1631
1632 /* Here, found a non-continuation before processing all expected bytes.
1633 * This byte indicates the beginning of a new character, so quit, even
1634 * if allowing this malformation. */
2b5e7bc2 1635 possible_problems |= UTF8_GOT_NON_CONTINUATION;
e308b348 1636 break;
eb83ed87
KW
1637 } /* End of loop through the character's bytes */
1638
1639 /* Save how many bytes were actually in the character */
1640 curlen = s - s0;
1641
2b5e7bc2
KW
1642 /* Note that there are two types of too-short malformation. One is when
1643 * there is actual wrong data before the normal termination of the
1644 * sequence. The other is that the sequence wasn't complete before the end
1645 * of the data we are allowed to look at, based on the input 'curlen'.
1646 * This means that we were passed data for a partial character, but it is
1647 * valid as far as we saw. The other is definitely invalid. This
1648 * distinction could be important to a caller, so the two types are kept
15b010f0
KW
1649 * separate.
1650 *
1651 * A convenience macro that matches either of the too-short conditions. */
1652# define UTF8_GOT_TOO_SHORT (UTF8_GOT_SHORT|UTF8_GOT_NON_CONTINUATION)
1653
1654 if (UNLIKELY(possible_problems & UTF8_GOT_TOO_SHORT)) {
1655 uv_so_far = uv;
1656 uv = UNICODE_REPLACEMENT;
1657 }
2b5e7bc2 1658
08e73697
KW
1659 /* Check for overflow. The algorithm requires us to not look past the end
1660 * of the current character, even if partial, so the upper limit is 's' */
e050c007
KW
1661 if (UNLIKELY(0 < does_utf8_overflow(s0, s,
1662 1 /* Do consider overlongs */
1663 )))
1664 {
2b5e7bc2
KW
1665 possible_problems |= UTF8_GOT_OVERFLOW;
1666 uv = UNICODE_REPLACEMENT;
eb83ed87 1667 }
eb83ed87 1668
2b5e7bc2
KW
1669 /* Check for overlong. If no problems so far, 'uv' is the correct code
1670 * point value. Simply see if it is expressible in fewer bytes. Otherwise
1671 * we must look at the UTF-8 byte sequence itself to see if it is for an
1672 * overlong */
1673 if ( ( LIKELY(! possible_problems)
1674 && UNLIKELY(expectlen > (STRLEN) OFFUNISKIP(uv)))
56576a04 1675 || ( UNLIKELY(possible_problems)
2b5e7bc2
KW
1676 && ( UNLIKELY(! UTF8_IS_START(*s0))
1677 || ( curlen > 1
d6be65ae 1678 && UNLIKELY(0 < is_utf8_overlong_given_start_byte_ok(s0,
08e73697 1679 s - s0))))))
2f8f112e 1680 {
2b5e7bc2
KW
1681 possible_problems |= UTF8_GOT_LONG;
1682
abc28b54 1683 if ( UNLIKELY( possible_problems & UTF8_GOT_TOO_SHORT)
56576a04 1684
abc28b54
KW
1685 /* The calculation in the 'true' branch of this 'if'
1686 * below won't work if overflows, and isn't needed
1687 * anyway. Further below we handle all overflow
1688 * cases */
1689 && LIKELY(! (possible_problems & UTF8_GOT_OVERFLOW)))
1690 {
2b5e7bc2
KW
1691 UV min_uv = uv_so_far;
1692 STRLEN i;
1693
1694 /* Here, the input is both overlong and is missing some trailing
1695 * bytes. There is no single code point it could be for, but there
1696 * may be enough information present to determine if what we have
1697 * so far is for an unallowed code point, such as for a surrogate.
56576a04
KW
1698 * The code further below has the intelligence to determine this,
1699 * but just for non-overlong UTF-8 sequences. What we do here is
1700 * calculate the smallest code point the input could represent if
1701 * there were no too short malformation. Then we compute and save
1702 * the UTF-8 for that, which is what the code below looks at
1703 * instead of the raw input. It turns out that the smallest such
1704 * code point is all we need. */
2b5e7bc2
KW
1705 for (i = curlen; i < expectlen; i++) {
1706 min_uv = UTF8_ACCUMULATE(min_uv,
1707 I8_TO_NATIVE_UTF8(UTF_CONTINUATION_MARK));
1708 }
1709
e9f2c446 1710 adjusted_s0 = temp_char_buf;
57ff5f59 1711 (void) uvoffuni_to_utf8_flags(adjusted_s0, min_uv, 0);
2b5e7bc2 1712 }
eb83ed87
KW
1713 }
1714
56576a04
KW
1715 /* Here, we have found all the possible problems, except for when the input
1716 * is for a problematic code point not allowed by the input parameters. */
1717
06188866
KW
1718 /* uv is valid for overlongs */
1719 if ( ( ( LIKELY(! (possible_problems & ~UTF8_GOT_LONG))
1720
1721 /* isn't problematic if < this */
1722 && uv >= UNICODE_SURROGATE_FIRST)
2b5e7bc2 1723 || ( UNLIKELY(possible_problems)
d60baaa7
KW
1724
1725 /* if overflow, we know without looking further
1726 * precisely which of the problematic types it is,
1727 * and we deal with those in the overflow handling
1728 * code */
1729 && LIKELY(! (possible_problems & UTF8_GOT_OVERFLOW))
57ff5f59
KW
1730 && ( isUTF8_POSSIBLY_PROBLEMATIC(*adjusted_s0)
1731 || UNLIKELY(isUTF8_PERL_EXTENDED(s0)))))
760c7c2f
KW
1732 && ((flags & ( UTF8_DISALLOW_NONCHAR
1733 |UTF8_DISALLOW_SURROGATE
1734 |UTF8_DISALLOW_SUPER
d044b7a7 1735 |UTF8_DISALLOW_PERL_EXTENDED
760c7c2f
KW
1736 |UTF8_WARN_NONCHAR
1737 |UTF8_WARN_SURROGATE
1738 |UTF8_WARN_SUPER
d22ec717 1739 |UTF8_WARN_PERL_EXTENDED))))
eb83ed87 1740 {
2b5e7bc2
KW
1741 /* If there were no malformations, or the only malformation is an
1742 * overlong, 'uv' is valid */
1743 if (LIKELY(! (possible_problems & ~UTF8_GOT_LONG))) {
1744 if (UNLIKELY(UNICODE_IS_SURROGATE(uv))) {
1745 possible_problems |= UTF8_GOT_SURROGATE;
1746 }
1747 else if (UNLIKELY(uv > PERL_UNICODE_MAX)) {
1748 possible_problems |= UTF8_GOT_SUPER;
1749 }
1750 else if (UNLIKELY(UNICODE_IS_NONCHAR(uv))) {
1751 possible_problems |= UTF8_GOT_NONCHAR;
1752 }
1753 }
1754 else { /* Otherwise, need to look at the source UTF-8, possibly
1755 adjusted to be non-overlong */
1756
1757 if (UNLIKELY(NATIVE_UTF8_TO_I8(*adjusted_s0)
1758 >= FIRST_START_BYTE_THAT_IS_DEFINITELY_SUPER))
ea5ced44 1759 {
2b5e7bc2
KW
1760 possible_problems |= UTF8_GOT_SUPER;
1761 }
1762 else if (curlen > 1) {
1763 if (UNLIKELY(IS_UTF8_2_BYTE_SUPER(
1764 NATIVE_UTF8_TO_I8(*adjusted_s0),
1765 NATIVE_UTF8_TO_I8(*(adjusted_s0 + 1)))))
ea5ced44 1766 {
2b5e7bc2 1767 possible_problems |= UTF8_GOT_SUPER;
ea5ced44 1768 }
2b5e7bc2
KW
1769 else if (UNLIKELY(IS_UTF8_2_BYTE_SURROGATE(
1770 NATIVE_UTF8_TO_I8(*adjusted_s0),
1771 NATIVE_UTF8_TO_I8(*(adjusted_s0 + 1)))))
1772 {
1773 possible_problems |= UTF8_GOT_SURROGATE;
ea5ced44
KW
1774 }
1775 }
c0236afe 1776
2b5e7bc2
KW
1777 /* We need a complete well-formed UTF-8 character to discern
1778 * non-characters, so can't look for them here */
1779 }
1780 }
949cf498 1781
2b5e7bc2
KW
1782 ready_to_handle_errors:
1783
1784 /* At this point:
1785 * curlen contains the number of bytes in the sequence that
1786 * this call should advance the input by.
e308b348
KW
1787 * avail_len gives the available number of bytes passed in, but
1788 * only if this is less than the expected number of
1789 * bytes, based on the code point's start byte.
2b5e7bc2
KW
1790 * possible_problems' is 0 if there weren't any problems; otherwise a bit
1791 * is set in it for each potential problem found.
1792 * uv contains the code point the input sequence
1793 * represents; or if there is a problem that prevents
1794 * a well-defined value from being computed, it is
1795 * some subsitute value, typically the REPLACEMENT
1796 * CHARACTER.
1797 * s0 points to the first byte of the character
56576a04
KW
1798 * s points to just after were we left off processing
1799 * the character
1800 * send points to just after where that character should
1801 * end, based on how many bytes the start byte tells
1802 * us should be in it, but no further than s0 +
1803 * avail_len
2b5e7bc2 1804 */
eb83ed87 1805
2b5e7bc2
KW
1806 if (UNLIKELY(possible_problems)) {
1807 bool disallowed = FALSE;
1808 const U32 orig_problems = possible_problems;
1809
37657a5b
KW
1810 if (msgs) {
1811 *msgs = NULL;
1812 }
1813
2b5e7bc2
KW
1814 while (possible_problems) { /* Handle each possible problem */
1815 UV pack_warn = 0;
1816 char * message = NULL;
37657a5b 1817 U32 this_flag_bit = 0;
2b5e7bc2
KW
1818
1819 /* Each 'if' clause handles one problem. They are ordered so that
1820 * the first ones' messages will be displayed before the later
6c64cd9d
KW
1821 * ones; this is kinda in decreasing severity order. But the
1822 * overlong must come last, as it changes 'uv' looked at by the
1823 * others */
2b5e7bc2
KW
1824 if (possible_problems & UTF8_GOT_OVERFLOW) {
1825
56576a04
KW
1826 /* Overflow means also got a super and are using Perl's
1827 * extended UTF-8, but we handle all three cases here */
2b5e7bc2 1828 possible_problems
d044b7a7 1829 &= ~(UTF8_GOT_OVERFLOW|UTF8_GOT_SUPER|UTF8_GOT_PERL_EXTENDED);
f9380377
KW
1830 *errors |= UTF8_GOT_OVERFLOW;
1831
1832 /* But the API says we flag all errors found */
1833 if (flags & (UTF8_WARN_SUPER|UTF8_DISALLOW_SUPER)) {
1834 *errors |= UTF8_GOT_SUPER;
1835 }
ddb65933 1836 if (flags
d044b7a7 1837 & (UTF8_WARN_PERL_EXTENDED|UTF8_DISALLOW_PERL_EXTENDED))
ddb65933 1838 {
d044b7a7 1839 *errors |= UTF8_GOT_PERL_EXTENDED;
f9380377 1840 }
2b5e7bc2 1841
d60baaa7 1842 /* Disallow if any of the three categories say to */
56576a04 1843 if ( ! (flags & UTF8_ALLOW_OVERFLOW)
d60baaa7 1844 || (flags & ( UTF8_DISALLOW_SUPER
d044b7a7 1845 |UTF8_DISALLOW_PERL_EXTENDED)))
d60baaa7
KW
1846 {
1847 disallowed = TRUE;
1848 }
1849
d22ec717
KW
1850 /* Likewise, warn if any say to */
1851 if ( ! (flags & UTF8_ALLOW_OVERFLOW)
1852 || (flags & (UTF8_WARN_SUPER|UTF8_WARN_PERL_EXTENDED)))
d60baaa7 1853 {
2b5e7bc2 1854
ddb65933
KW
1855 /* The warnings code explicitly says it doesn't handle the
1856 * case of packWARN2 and two categories which have
1857 * parent-child relationship. Even if it works now to
1858 * raise the warning if either is enabled, it wouldn't
1859 * necessarily do so in the future. We output (only) the
56576a04 1860 * most dire warning */
ddb65933 1861 if (! (flags & UTF8_CHECK_ONLY)) {
37657a5b 1862 if (msgs || ckWARN_d(WARN_UTF8)) {
ddb65933
KW
1863 pack_warn = packWARN(WARN_UTF8);
1864 }
37657a5b 1865 else if (msgs || ckWARN_d(WARN_NON_UNICODE)) {
ddb65933
KW
1866 pack_warn = packWARN(WARN_NON_UNICODE);
1867 }
1868 if (pack_warn) {
1869 message = Perl_form(aTHX_ "%s: %s (overflows)",
1870 malformed_text,
05b9033b 1871 _byte_dump_string(s0, curlen, 0));
37657a5b 1872 this_flag_bit = UTF8_GOT_OVERFLOW;
ddb65933 1873 }
2b5e7bc2
KW
1874 }
1875 }
1876 }
1877 else if (possible_problems & UTF8_GOT_EMPTY) {
1878 possible_problems &= ~UTF8_GOT_EMPTY;
f9380377 1879 *errors |= UTF8_GOT_EMPTY;
2b5e7bc2
KW
1880
1881 if (! (flags & UTF8_ALLOW_EMPTY)) {
d1f8d421
KW
1882
1883 /* This so-called malformation is now treated as a bug in
1884 * the caller. If you have nothing to decode, skip calling
1885 * this function */
1886 assert(0);
1887
2b5e7bc2 1888 disallowed = TRUE;
37657a5b
KW
1889 if ( (msgs
1890 || ckWARN_d(WARN_UTF8)) && ! (flags & UTF8_CHECK_ONLY))
1891 {
2b5e7bc2
KW
1892 pack_warn = packWARN(WARN_UTF8);
1893 message = Perl_form(aTHX_ "%s (empty string)",
1894 malformed_text);
37657a5b 1895 this_flag_bit = UTF8_GOT_EMPTY;
2b5e7bc2
KW
1896 }
1897 }
1898 }
1899 else if (possible_problems & UTF8_GOT_CONTINUATION) {
1900 possible_problems &= ~UTF8_GOT_CONTINUATION;
f9380377 1901 *errors |= UTF8_GOT_CONTINUATION;
2b5e7bc2
KW
1902
1903 if (! (flags & UTF8_ALLOW_CONTINUATION)) {
1904 disallowed = TRUE;
37657a5b
KW
1905 if (( msgs
1906 || ckWARN_d(WARN_UTF8)) && ! (flags & UTF8_CHECK_ONLY))
1907 {
2b5e7bc2
KW
1908 pack_warn = packWARN(WARN_UTF8);
1909 message = Perl_form(aTHX_
1910 "%s: %s (unexpected continuation byte 0x%02x,"
1911 " with no preceding start byte)",
1912 malformed_text,
7e2f38b2 1913 _byte_dump_string(s0, 1, 0), *s0);
37657a5b 1914 this_flag_bit = UTF8_GOT_CONTINUATION;
2b5e7bc2
KW
1915 }
1916 }
1917 }
2b5e7bc2
KW
1918 else if (possible_problems & UTF8_GOT_SHORT) {
1919 possible_problems &= ~UTF8_GOT_SHORT;
f9380377 1920 *errors |= UTF8_GOT_SHORT;
2b5e7bc2
KW
1921
1922 if (! (flags & UTF8_ALLOW_SHORT)) {
1923 disallowed = TRUE;
37657a5b
KW
1924 if (( msgs
1925 || ckWARN_d(WARN_UTF8)) && ! (flags & UTF8_CHECK_ONLY))
1926 {
2b5e7bc2
KW
1927 pack_warn = packWARN(WARN_UTF8);
1928 message = Perl_form(aTHX_
56576a04
KW
1929 "%s: %s (too short; %d byte%s available, need %d)",
1930 malformed_text,
1931 _byte_dump_string(s0, send - s0, 0),
1932 (int)avail_len,
1933 avail_len == 1 ? "" : "s",
1934 (int)expectlen);
37657a5b 1935 this_flag_bit = UTF8_GOT_SHORT;
2b5e7bc2
KW
1936 }
1937 }
ba210ebe 1938
2b5e7bc2 1939 }
e308b348
KW
1940 else if (possible_problems & UTF8_GOT_NON_CONTINUATION) {
1941 possible_problems &= ~UTF8_GOT_NON_CONTINUATION;
1942 *errors |= UTF8_GOT_NON_CONTINUATION;
1943
1944 if (! (flags & UTF8_ALLOW_NON_CONTINUATION)) {
1945 disallowed = TRUE;
37657a5b
KW
1946 if (( msgs
1947 || ckWARN_d(WARN_UTF8)) && ! (flags & UTF8_CHECK_ONLY))
1948 {
99a765e9
KW
1949
1950 /* If we don't know for sure that the input length is
1951 * valid, avoid as much as possible reading past the
1952 * end of the buffer */
1953 int printlen = (flags & _UTF8_NO_CONFIDENCE_IN_CURLEN)
1954 ? s - s0
1955 : send - s0;
e308b348
KW
1956 pack_warn = packWARN(WARN_UTF8);
1957 message = Perl_form(aTHX_ "%s",
1958 unexpected_non_continuation_text(s0,
99a765e9 1959 printlen,
e308b348
KW
1960 s - s0,
1961 (int) expectlen));
37657a5b 1962 this_flag_bit = UTF8_GOT_NON_CONTINUATION;
e308b348
KW
1963 }
1964 }
1965 }
2b5e7bc2
KW
1966 else if (possible_problems & UTF8_GOT_SURROGATE) {
1967 possible_problems &= ~UTF8_GOT_SURROGATE;
1968
f9380377
KW
1969 if (flags & UTF8_WARN_SURROGATE) {
1970 *errors |= UTF8_GOT_SURROGATE;
1971
1972 if ( ! (flags & UTF8_CHECK_ONLY)
37657a5b 1973 && (msgs || ckWARN_d(WARN_SURROGATE)))
f9380377 1974 {
2b5e7bc2
KW
1975 pack_warn = packWARN(WARN_SURROGATE);
1976
1977 /* These are the only errors that can occur with a
1978 * surrogate when the 'uv' isn't valid */
1979 if (orig_problems & UTF8_GOT_TOO_SHORT) {
1980 message = Perl_form(aTHX_
1981 "UTF-16 surrogate (any UTF-8 sequence that"
1982 " starts with \"%s\" is for a surrogate)",
7e2f38b2 1983 _byte_dump_string(s0, curlen, 0));
2b5e7bc2
KW
1984 }
1985 else {
c94c2f39 1986 message = Perl_form(aTHX_ surrogate_cp_format, uv);
2b5e7bc2 1987 }
37657a5b 1988 this_flag_bit = UTF8_GOT_SURROGATE;
f9380377 1989 }
2b5e7bc2 1990 }
ba210ebe 1991
2b5e7bc2
KW
1992 if (flags & UTF8_DISALLOW_SURROGATE) {
1993 disallowed = TRUE;
f9380377 1994 *errors |= UTF8_GOT_SURROGATE;
2b5e7bc2
KW
1995 }
1996 }
1997 else if (possible_problems & UTF8_GOT_SUPER) {
1998 possible_problems &= ~UTF8_GOT_SUPER;
949cf498 1999
f9380377
KW
2000 if (flags & UTF8_WARN_SUPER) {
2001 *errors |= UTF8_GOT_SUPER;
2002
2003 if ( ! (flags & UTF8_CHECK_ONLY)
37657a5b 2004 && (msgs || ckWARN_d(WARN_NON_UNICODE)))
f9380377 2005 {
2b5e7bc2
KW
2006 pack_warn = packWARN(WARN_NON_UNICODE);
2007
2008 if (orig_problems & UTF8_GOT_TOO_SHORT) {
2009 message = Perl_form(aTHX_
2010 "Any UTF-8 sequence that starts with"
2011 " \"%s\" is for a non-Unicode code point,"
2012 " may not be portable",
7e2f38b2 2013 _byte_dump_string(s0, curlen, 0));
2b5e7bc2
KW
2014 }
2015 else {
c94c2f39 2016 message = Perl_form(aTHX_ super_cp_format, uv);
2b5e7bc2 2017 }
37657a5b 2018 this_flag_bit = UTF8_GOT_SUPER;
f9380377 2019 }
2b5e7bc2 2020 }
ba210ebe 2021
57ff5f59
KW
2022 /* Test for Perl's extended UTF-8 after the regular SUPER ones,
2023 * and before possibly bailing out, so that the more dire
2024 * warning will override the regular one. */
2025 if (UNLIKELY(isUTF8_PERL_EXTENDED(s0))) {
2b5e7bc2 2026 if ( ! (flags & UTF8_CHECK_ONLY)
d044b7a7 2027 && (flags & (UTF8_WARN_PERL_EXTENDED|UTF8_WARN_SUPER))
37657a5b 2028 && (msgs || ckWARN_d(WARN_NON_UNICODE)))
2b5e7bc2 2029 {
db0f09e6 2030 pack_warn = packWARN(WARN_NON_UNICODE);
2b5e7bc2 2031
57ff5f59
KW
2032 /* If it is an overlong that evaluates to a code point
2033 * that doesn't have to use the Perl extended UTF-8, it
2034 * still used it, and so we output a message that
2035 * doesn't refer to the code point. The same is true
2036 * if there was a SHORT malformation where the code
2037 * point is not valid. In that case, 'uv' will have
2038 * been set to the REPLACEMENT CHAR, and the message
2039 * below without the code point in it will be selected
2040 * */
2041 if (UNICODE_IS_PERL_EXTENDED(uv)) {
2b5e7bc2 2042 message = Perl_form(aTHX_
57ff5f59 2043 perl_extended_cp_format, uv);
2b5e7bc2
KW
2044 }
2045 else {
2046 message = Perl_form(aTHX_
57ff5f59
KW
2047 "Any UTF-8 sequence that starts with"
2048 " \"%s\" is a Perl extension, and"
2049 " so is not portable",
2050 _byte_dump_string(s0, curlen, 0));
2b5e7bc2 2051 }
37657a5b 2052 this_flag_bit = UTF8_GOT_PERL_EXTENDED;
2b5e7bc2
KW
2053 }
2054
d044b7a7
KW
2055 if (flags & ( UTF8_WARN_PERL_EXTENDED
2056 |UTF8_DISALLOW_PERL_EXTENDED))
ddb65933 2057 {
d044b7a7 2058 *errors |= UTF8_GOT_PERL_EXTENDED;
f9380377 2059
d044b7a7 2060 if (flags & UTF8_DISALLOW_PERL_EXTENDED) {
f9380377
KW
2061 disallowed = TRUE;
2062 }
2b5e7bc2
KW
2063 }
2064 }
eb83ed87 2065
2b5e7bc2 2066 if (flags & UTF8_DISALLOW_SUPER) {
f9380377 2067 *errors |= UTF8_GOT_SUPER;
2b5e7bc2
KW
2068 disallowed = TRUE;
2069 }
2b5e7bc2
KW
2070 }
2071 else if (possible_problems & UTF8_GOT_NONCHAR) {
2072 possible_problems &= ~UTF8_GOT_NONCHAR;
ba210ebe 2073
f9380377
KW
2074 if (flags & UTF8_WARN_NONCHAR) {
2075 *errors |= UTF8_GOT_NONCHAR;
2076
2077 if ( ! (flags & UTF8_CHECK_ONLY)
37657a5b 2078 && (msgs || ckWARN_d(WARN_NONCHAR)))
f9380377 2079 {
2b5e7bc2
KW
2080 /* The code above should have guaranteed that we don't
2081 * get here with errors other than overlong */
2082 assert (! (orig_problems
2083 & ~(UTF8_GOT_LONG|UTF8_GOT_NONCHAR)));
2084
2085 pack_warn = packWARN(WARN_NONCHAR);
c94c2f39 2086 message = Perl_form(aTHX_ nonchar_cp_format, uv);
37657a5b 2087 this_flag_bit = UTF8_GOT_NONCHAR;
f9380377 2088 }
2b5e7bc2 2089 }
5b311467 2090
2b5e7bc2
KW
2091 if (flags & UTF8_DISALLOW_NONCHAR) {
2092 disallowed = TRUE;
f9380377 2093 *errors |= UTF8_GOT_NONCHAR;
2b5e7bc2 2094 }
6c64cd9d
KW
2095 }
2096 else if (possible_problems & UTF8_GOT_LONG) {
2097 possible_problems &= ~UTF8_GOT_LONG;
2098 *errors |= UTF8_GOT_LONG;
2099
2100 if (flags & UTF8_ALLOW_LONG) {
2101
2102 /* We don't allow the actual overlong value, unless the
2103 * special extra bit is also set */
2104 if (! (flags & ( UTF8_ALLOW_LONG_AND_ITS_VALUE
2105 & ~UTF8_ALLOW_LONG)))
2106 {
2107 uv = UNICODE_REPLACEMENT;
2108 }
2109 }
2110 else {
2111 disallowed = TRUE;
2112
37657a5b
KW
2113 if (( msgs
2114 || ckWARN_d(WARN_UTF8)) && ! (flags & UTF8_CHECK_ONLY))
2115 {
6c64cd9d
KW
2116 pack_warn = packWARN(WARN_UTF8);
2117
2118 /* These error types cause 'uv' to be something that
2119 * isn't what was intended, so can't use it in the
2120 * message. The other error types either can't
2121 * generate an overlong, or else the 'uv' is valid */
2122 if (orig_problems &
2123 (UTF8_GOT_TOO_SHORT|UTF8_GOT_OVERFLOW))
2124 {
2125 message = Perl_form(aTHX_
2126 "%s: %s (any UTF-8 sequence that starts"
2127 " with \"%s\" is overlong which can and"
2128 " should be represented with a"
2129 " different, shorter sequence)",
2130 malformed_text,
2131 _byte_dump_string(s0, send - s0, 0),
2132 _byte_dump_string(s0, curlen, 0));
2133 }
2134 else {
2135 U8 tmpbuf[UTF8_MAXBYTES+1];
1be62ab9
KW
2136 const U8 * const e = uvoffuni_to_utf8_flags(tmpbuf,
2137 uv, 0);
d819dc50
KW
2138 /* Don't use U+ for non-Unicode code points, which
2139 * includes those in the Latin1 range */
2140 const char * preface = ( uv > PERL_UNICODE_MAX
2141#ifdef EBCDIC
2142 || uv <= 0xFF
2143#endif
2144 )
2145 ? "0x"
2146 : "U+";
6c64cd9d
KW
2147 message = Perl_form(aTHX_
2148 "%s: %s (overlong; instead use %s to represent"
2149 " %s%0*" UVXf ")",
2150 malformed_text,
2151 _byte_dump_string(s0, send - s0, 0),
2152 _byte_dump_string(tmpbuf, e - tmpbuf, 0),
2153 preface,
2154 ((uv < 256) ? 2 : 4), /* Field width of 2 for
2155 small code points */
1be62ab9 2156 UNI_TO_NATIVE(uv));
6c64cd9d 2157 }
37657a5b 2158 this_flag_bit = UTF8_GOT_LONG;
6c64cd9d
KW
2159 }
2160 }
2b5e7bc2
KW
2161 } /* End of looking through the possible flags */
2162
2163 /* Display the message (if any) for the problem being handled in
2164 * this iteration of the loop */
2165 if (message) {
37657a5b 2166 if (msgs) {
37657a5b
KW
2167 assert(this_flag_bit);
2168
2169 if (*msgs == NULL) {
2170 *msgs = newAV();
2171 }
2172
bb07812e
KW
2173 av_push(*msgs, newRV_noinc((SV*) new_msg_hv(message,
2174 pack_warn,
2175 this_flag_bit)));
37657a5b
KW
2176 }
2177 else if (PL_op)
2b5e7bc2
KW
2178 Perl_warner(aTHX_ pack_warn, "%s in %s", message,
2179 OP_DESC(PL_op));
2180 else
2181 Perl_warner(aTHX_ pack_warn, "%s", message);
2182 }
ddb65933 2183 } /* End of 'while (possible_problems)' */
a0dbb045 2184
2b5e7bc2
KW
2185 /* Since there was a possible problem, the returned length may need to
2186 * be changed from the one stored at the beginning of this function.
2187 * Instead of trying to figure out if that's needed, just do it. */
2188 if (retlen) {
2189 *retlen = curlen;
2190 }
a0dbb045 2191
2b5e7bc2
KW
2192 if (disallowed) {
2193 if (flags & UTF8_CHECK_ONLY && retlen) {
2194 *retlen = ((STRLEN) -1);
2195 }
2196 return 0;
2197 }
eb83ed87 2198 }
ba210ebe 2199
2b5e7bc2 2200 return UNI_TO_NATIVE(uv);
a0ed51b3
LW
2201}
2202
8e84507e 2203/*
ec5f19d0
KW
2204=for apidoc utf8_to_uvchr_buf
2205
2206Returns the native code point of the first character in the string C<s> which
2207is assumed to be in UTF-8 encoding; C<send> points to 1 beyond the end of C<s>.
524080c4 2208C<*retlen> will be set to the length, in bytes, of that character.
ec5f19d0 2209
524080c4
KW
2210If C<s> does not point to a well-formed UTF-8 character and UTF8 warnings are
2211enabled, zero is returned and C<*retlen> is set (if C<retlen> isn't
796b6530 2212C<NULL>) to -1. If those warnings are off, the computed value, if well-defined
173db420 2213(or the Unicode REPLACEMENT CHARACTER if not), is silently returned, and
796b6530 2214C<*retlen> is set (if C<retlen> isn't C<NULL>) so that (S<C<s> + C<*retlen>>) is
173db420 2215the next possible position in C<s> that could begin a non-malformed character.
de69f3af 2216See L</utf8n_to_uvchr> for details on when the REPLACEMENT CHARACTER is
173db420 2217returned.
ec5f19d0
KW
2218
2219=cut
52be2536
KW
2220
2221Also implemented as a macro in utf8.h
2222
ec5f19d0
KW
2223*/
2224
2225
2226UV
2227Perl_utf8_to_uvchr_buf(pTHX_ const U8 *s, const U8 *send, STRLEN *retlen)
2228{
7f974d7e
KW
2229 PERL_ARGS_ASSERT_UTF8_TO_UVCHR_BUF;
2230
ec5f19d0
KW
2231 assert(s < send);
2232
2233 return utf8n_to_uvchr(s, send - s, retlen,
ddb65933 2234 ckWARN_d(WARN_UTF8) ? 0 : UTF8_ALLOW_ANY);
ec5f19d0
KW
2235}
2236
52be2536
KW
2237/* This is marked as deprecated
2238 *
ec5f19d0
KW
2239=for apidoc utf8_to_uvuni_buf
2240
de69f3af
KW
2241Only in very rare circumstances should code need to be dealing in Unicode
2242(as opposed to native) code points. In those few cases, use
07dfe0a4
KW
2243C<L<NATIVE_TO_UNI(utf8_to_uvchr_buf(...))|/utf8_to_uvchr_buf>> instead. If you
2244are not absolutely sure this is one of those cases, then assume it isn't and
2245use plain C<utf8_to_uvchr_buf> instead.
4f83cdcd
KW
2246
2247Returns the Unicode (not-native) code point of the first character in the
2248string C<s> which
ec5f19d0
KW
2249is assumed to be in UTF-8 encoding; C<send> points to 1 beyond the end of C<s>.
2250C<retlen> will be set to the length, in bytes, of that character.
2251
524080c4
KW
2252If C<s> does not point to a well-formed UTF-8 character and UTF8 warnings are
2253enabled, zero is returned and C<*retlen> is set (if C<retlen> isn't
2254NULL) to -1. If those warnings are off, the computed value if well-defined (or
2255the Unicode REPLACEMENT CHARACTER, if not) is silently returned, and C<*retlen>
2256is set (if C<retlen> isn't NULL) so that (S<C<s> + C<*retlen>>) is the
2257next possible position in C<s> that could begin a non-malformed character.
de69f3af 2258See L</utf8n_to_uvchr> for details on when the REPLACEMENT CHARACTER is returned.
ec5f19d0
KW
2259
2260=cut
2261*/
2262
2263UV
2264Perl_utf8_to_uvuni_buf(pTHX_ const U8 *s, const U8 *send, STRLEN *retlen)
2265{
2266 PERL_ARGS_ASSERT_UTF8_TO_UVUNI_BUF;
2267
2268 assert(send > s);
2269
5962d97e 2270 return NATIVE_TO_UNI(utf8_to_uvchr_buf(s, send, retlen));
ec5f19d0
KW
2271}
2272
b76347f2 2273/*
87cea99e 2274=for apidoc utf8_length
b76347f2 2275
b2e7ed74
KW
2276Returns the number of characters in the sequence of UTF-8-encoded bytes starting
2277at C<s> and ending at the byte just before C<e>. If <s> and <e> point to the
2278same place, it returns 0 with no warning raised.
2279
2280If C<e E<lt> s> or if the scan would end up past C<e>, it raises a UTF8 warning
2281and returns the number of valid characters.
b76347f2
JH
2282
2283=cut
2284*/
2285
2286STRLEN
35a4481c 2287Perl_utf8_length(pTHX_ const U8 *s, const U8 *e)
b76347f2
JH
2288{
2289 STRLEN len = 0;
2290
7918f24d
NC
2291 PERL_ARGS_ASSERT_UTF8_LENGTH;
2292
8850bf83
JH
2293 /* Note: cannot use UTF8_IS_...() too eagerly here since e.g.
2294 * the bitops (especially ~) can create illegal UTF-8.
2295 * In other words: in Perl UTF-8 is not just for Unicode. */
2296
a3b680e6
AL
2297 if (e < s)
2298 goto warn_and_return;
b76347f2 2299 while (s < e) {
4cbf4130 2300 s += UTF8SKIP(s);
8e91ec7f
AV
2301 len++;
2302 }
2303
2304 if (e != s) {
2305 len--;
2306 warn_and_return:
9b387841
NC
2307 if (PL_op)
2308 Perl_ck_warner_d(aTHX_ packWARN(WARN_UTF8),
2309 "%s in %s", unees, OP_DESC(PL_op));
2310 else
61a12c31 2311 Perl_ck_warner_d(aTHX_ packWARN(WARN_UTF8), "%s", unees);
b76347f2
JH
2312 }
2313
2314 return len;
2315}
2316
b06226ff 2317/*
fed3ba5d
NC
2318=for apidoc bytes_cmp_utf8
2319
a1433954 2320Compares the sequence of characters (stored as octets) in C<b>, C<blen> with the
72d33970
FC
2321sequence of characters (stored as UTF-8)
2322in C<u>, C<ulen>. Returns 0 if they are
fed3ba5d
NC
2323equal, -1 or -2 if the first string is less than the second string, +1 or +2
2324if the first string is greater than the second string.
2325
2326-1 or +1 is returned if the shorter string was identical to the start of the
72d33970
FC
2327longer string. -2 or +2 is returned if
2328there was a difference between characters
fed3ba5d
NC
2329within the strings.
2330
2331=cut
2332*/
2333
2334int
2335Perl_bytes_cmp_utf8(pTHX_ const U8 *b, STRLEN blen, const U8 *u, STRLEN ulen)
2336{
2337 const U8 *const bend = b + blen;
2338 const U8 *const uend = u + ulen;
2339
2340 PERL_ARGS_ASSERT_BYTES_CMP_UTF8;
fed3ba5d
NC
2341
2342 while (b < bend && u < uend) {
2343 U8 c = *u++;
2344 if (!UTF8_IS_INVARIANT(c)) {
2345 if (UTF8_IS_DOWNGRADEABLE_START(c)) {
2346 if (u < uend) {
2347 U8 c1 = *u++;
2348 if (UTF8_IS_CONTINUATION(c1)) {
a62b247b 2349 c = EIGHT_BIT_UTF8_TO_NATIVE(c, c1);
fed3ba5d 2350 } else {
2b5e7bc2 2351 /* diag_listed_as: Malformed UTF-8 character%s */
fed3ba5d 2352 Perl_ck_warner_d(aTHX_ packWARN(WARN_UTF8),
56576a04
KW
2353 "%s %s%s",
2354 unexpected_non_continuation_text(u - 2, 2, 1, 2),
2355 PL_op ? " in " : "",
2356 PL_op ? OP_DESC(PL_op) : "");
fed3ba5d
NC
2357 return -2;
2358 }
2359 } else {
2360 if (PL_op)
2361 Perl_ck_warner_d(aTHX_ packWARN(WARN_UTF8),
2362 "%s in %s", unees, OP_DESC(PL_op));
2363 else
61a12c31 2364 Perl_ck_warner_d(aTHX_ packWARN(WARN_UTF8), "%s", unees);
fed3ba5d
NC
2365 return -2; /* Really want to return undef :-) */
2366 }
2367 } else {
2368 return -2;
2369 }
2370 }
2371 if (*b != c) {
2372 return *b < c ? -2 : +2;
2373 }
2374 ++b;
2375 }
2376
2377 if (b == bend && u == uend)
2378 return 0;
2379
2380 return b < bend ? +1 : -1;
2381}
2382
2383/*
87cea99e 2384=for apidoc utf8_to_bytes
6940069f 2385
3bc0c78c 2386Converts a string C<"s"> of length C<*lenp> from UTF-8 into native byte encoding.
a1433954 2387Unlike L</bytes_to_utf8>, this over-writes the original string, and
09af0336 2388updates C<*lenp> to contain the new length.
3bc0c78c
KW
2389Returns zero on failure (leaving C<"s"> unchanged) setting C<*lenp> to -1.
2390
2391Upon successful return, the number of variants in the string can be computed by
23b37b12
KW
2392having saved the value of C<*lenp> before the call, and subtracting the
2393after-call value of C<*lenp> from it.
6940069f 2394
a1433954 2395If you need a copy of the string, see L</bytes_from_utf8>.
95be277c 2396
6940069f
GS
2397=cut
2398*/
2399
2400U8 *
09af0336 2401Perl_utf8_to_bytes(pTHX_ U8 *s, STRLEN *lenp)
6940069f 2402{
9fe0d3c2 2403 U8 * first_variant;
246fae53 2404
7918f24d 2405 PERL_ARGS_ASSERT_UTF8_TO_BYTES;
81611534 2406 PERL_UNUSED_CONTEXT;
7918f24d 2407
9fe0d3c2 2408 /* This is a no-op if no variants at all in the input */
09af0336 2409 if (is_utf8_invariant_string_loc(s, *lenp, (const U8 **) &first_variant)) {
9fe0d3c2
KW
2410 return s;
2411 }
2412
2413 {
3c5aa262 2414 U8 * const save = s;
09af0336 2415 U8 * const send = s + *lenp;
3c5aa262
KW
2416 U8 * d;
2417
2418 /* Nothing before the first variant needs to be changed, so start the real
2419 * work there */
2420 s = first_variant;
2421 while (s < send) {
2422 if (! UTF8_IS_INVARIANT(*s)) {
2423 if (! UTF8_IS_NEXT_CHAR_DOWNGRADEABLE(s, send)) {
09af0336 2424 *lenp = ((STRLEN) -1);
3c5aa262
KW
2425 return 0;
2426 }
2427 s++;
d59937ca
KW
2428 }
2429 s++;
dcad2880 2430 }
dcad2880 2431
3c5aa262
KW
2432 /* Is downgradable, so do it */
2433 d = s = first_variant;
2434 while (s < send) {
2435 U8 c = *s++;
2436 if (! UVCHR_IS_INVARIANT(c)) {
2437 /* Then it is two-byte encoded */
2438 c = EIGHT_BIT_UTF8_TO_NATIVE(c, *s);
2439 s++;
2440 }
2441 *d++ = c;
2442 }
2443 *d = '\0';
09af0336 2444 *lenp = d - save;
3c5aa262
KW
2445
2446 return save;
9fe0d3c2 2447 }
6940069f
GS
2448}
2449
2450/*
87cea99e 2451=for apidoc bytes_from_utf8
f9a63242 2452
09af0336 2453Converts a potentially UTF-8 encoded string C<s> of length C<*lenp> into native
41ae6089 2454byte encoding. On input, the boolean C<*is_utf8p> gives whether or not C<s> is
4f3d592d
KW
2455actually encoded in UTF-8.
2456
2457Unlike L</utf8_to_bytes> but like L</bytes_to_utf8>, this is non-destructive of
2458the input string.
2459
41ae6089
KW
2460Do nothing if C<*is_utf8p> is 0, or if there are code points in the string
2461not expressible in native byte encoding. In these cases, C<*is_utf8p> and
09af0336 2462C<*lenp> are unchanged, and the return value is the original C<s>.
4f3d592d 2463
41ae6089 2464Otherwise, C<*is_utf8p> is set to 0, and the return value is a pointer to a
4f3d592d 2465newly created string containing a downgraded copy of C<s>, and whose length is
9ff99fb3
KW
2466returned in C<*lenp>, updated. The new string is C<NUL>-terminated. The
2467caller is responsible for arranging for the memory used by this string to get
2468freed.
f9a63242 2469
3bc0c78c 2470Upon successful return, the number of variants in the string can be computed by
23b37b12
KW
2471having saved the value of C<*lenp> before the call, and subtracting the
2472after-call value of C<*lenp> from it.
3bc0c78c 2473
37607a96 2474=cut
976c1b08
KW
2475
2476There is a macro that avoids this function call, but this is retained for
2477anyone who calls it with the Perl_ prefix */
f9a63242
JH
2478
2479U8 *
41ae6089 2480Perl_bytes_from_utf8(pTHX_ const U8 *s, STRLEN *lenp, bool *is_utf8p)
f9a63242 2481{
7918f24d 2482 PERL_ARGS_ASSERT_BYTES_FROM_UTF8;
96a5add6 2483 PERL_UNUSED_CONTEXT;
f9a63242 2484
976c1b08
KW
2485 return bytes_from_utf8_loc(s, lenp, is_utf8p, NULL);
2486}
2487
2488/*
2489No = here because currently externally undocumented
2490for apidoc bytes_from_utf8_loc
2491
2492Like C<L</bytes_from_utf8>()>, but takes an extra parameter, a pointer to where
2493to store the location of the first character in C<"s"> that cannot be
2494converted to non-UTF8.
2495
2496If that parameter is C<NULL>, this function behaves identically to
2497C<bytes_from_utf8>.
2498
2499Otherwise if C<*is_utf8p> is 0 on input, the function behaves identically to
2500C<bytes_from_utf8>, except it also sets C<*first_non_downgradable> to C<NULL>.
2501
2502Otherwise, the function returns a newly created C<NUL>-terminated string
2503containing the non-UTF8 equivalent of the convertible first portion of
2504C<"s">. C<*lenp> is set to its length, not including the terminating C<NUL>.
2505If the entire input string was converted, C<*is_utf8p> is set to a FALSE value,
2506and C<*first_non_downgradable> is set to C<NULL>.
2507
2508Otherwise, C<*first_non_downgradable> set to point to the first byte of the
2509first character in the original string that wasn't converted. C<*is_utf8p> is
2510unchanged. Note that the new string may have length 0.
2511
2512Another way to look at it is, if C<*first_non_downgradable> is non-C<NULL> and
2513C<*is_utf8p> is TRUE, this function starts at the beginning of C<"s"> and
2514converts as many characters in it as possible stopping at the first one it
385b74be 2515finds that can't be converted to non-UTF-8. C<*first_non_downgradable> is
976c1b08
KW
2516set to point to that. The function returns the portion that could be converted
2517in a newly created C<NUL>-terminated string, and C<*lenp> is set to its length,
2518not including the terminating C<NUL>. If the very first character in the
2519original could not be converted, C<*lenp> will be 0, and the new string will
2520contain just a single C<NUL>. If the entire input string was converted,
2521C<*is_utf8p> is set to FALSE and C<*first_non_downgradable> is set to C<NULL>.
2522
2523Upon successful return, the number of variants in the converted portion of the
2524string can be computed by having saved the value of C<*lenp> before the call,
2525and subtracting the after-call value of C<*lenp> from it.
2526
2527=cut
2528
2529
2530*/
2531
2532U8 *
2533Perl_bytes_from_utf8_loc(const U8 *s, STRLEN *lenp, bool *is_utf8p, const U8** first_unconverted)
2534{
2535 U8 *d;
2536 const U8 *original = s;
2537 U8 *converted_start;
2538 const U8 *send = s + *lenp;
f9a63242 2539
976c1b08 2540 PERL_ARGS_ASSERT_BYTES_FROM_UTF8_LOC;
170a1c22 2541
976c1b08
KW
2542 if (! *is_utf8p) {
2543 if (first_unconverted) {
2544 *first_unconverted = NULL;
2545 }
2546
2547 return (U8 *) original;
2548 }
2549
2550 Newx(d, (*lenp) + 1, U8);
2551
2552 converted_start = d;
7299a045
KW
2553 while (s < send) {
2554 U8 c = *s++;
2555 if (! UTF8_IS_INVARIANT(c)) {
976c1b08
KW
2556
2557 /* Then it is multi-byte encoded. If the code point is above 0xFF,
2558 * have to stop now */
2559 if (UNLIKELY (! UTF8_IS_NEXT_CHAR_DOWNGRADEABLE(s - 1, send))) {
2560 if (first_unconverted) {
2561 *first_unconverted = s - 1;
2562 goto finish_and_return;
2563 }
2564 else {
2565 Safefree(converted_start);
2566 return (U8 *) original;
2567 }
2568 }
2569
7299a045
KW
2570 c = EIGHT_BIT_UTF8_TO_NATIVE(c, *s);
2571 s++;
38af28cf 2572 }
7299a045
KW
2573 *d++ = c;
2574 }
170a1c22 2575
976c1b08
KW
2576 /* Here, converted the whole of the input */
2577 *is_utf8p = FALSE;
2578 if (first_unconverted) {
2579 *first_unconverted = NULL;
170a1c22 2580 }
976c1b08
KW
2581
2582 finish_and_return:
46a08a6f
KW
2583 *d = '\0';
2584 *lenp = d - converted_start;
976c1b08
KW
2585
2586 /* Trim unused space */
2587 Renew(converted_start, *lenp + 1, U8);
2588
2589 return converted_start;
f9a63242
JH
2590}
2591
2592/*
87cea99e 2593=for apidoc bytes_to_utf8
6940069f 2594
09af0336 2595Converts a string C<s> of length C<*lenp> bytes from the native encoding into
ff97e5cf 2596UTF-8.
09af0336 2597Returns a pointer to the newly-created string, and sets C<*lenp> to
9ff99fb3
KW
2598reflect the new length in bytes. The caller is responsible for arranging for
2599the memory used by this string to get freed.
6940069f 2600
3bc0c78c 2601Upon successful return, the number of variants in the string can be computed by
23b37b12 2602having saved the value of C<*lenp> before the call, and subtracting it from the
3bc0c78c
KW
2603after-call value of C<*lenp>.
2604
75200dff 2605A C<NUL> character will be written after the end of the string.
2bbc8d55
SP
2606
2607If you want to convert to UTF-8 from encodings other than
2608the native (Latin1 or EBCDIC),
a1433954 2609see L</sv_recode_to_utf8>().
c9ada85f 2610
497711e7 2611=cut
6940069f
GS
2612*/
2613
2614U8*
09af0336 2615Perl_bytes_to_utf8(pTHX_ const U8 *s, STRLEN *lenp)
6940069f 2616{
09af0336 2617 const U8 * const send = s + (*lenp);
6940069f
GS
2618 U8 *d;
2619 U8 *dst;
7918f24d
NC
2620
2621 PERL_ARGS_ASSERT_BYTES_TO_UTF8;
96a5add6 2622 PERL_UNUSED_CONTEXT;
6940069f 2623
09af0336 2624 Newx(d, (*lenp) * 2 + 1, U8);
6940069f
GS
2625 dst = d;
2626
2627 while (s < send) {
55d09dc8
KW
2628 append_utf8_from_native_byte(*s, &d);
2629 s++;
6940069f 2630 }
2e11cf67 2631
6940069f 2632 *d = '\0';
09af0336 2633 *lenp = d-dst;
2e11cf67
KW
2634
2635 /* Trim unused space */
2636 Renew(dst, *lenp + 1, U8);
2637
6940069f
GS
2638 return dst;
2639}
2640
a0ed51b3 2641/*
624504c5
KW
2642 * Convert native (big-endian) UTF-16 to UTF-8. For reversed (little-endian),
2643 * use utf16_to_utf8_reversed().
a0ed51b3 2644 *
624504c5
KW
2645 * UTF-16 requires 2 bytes for every code point below 0x10000; otherwise 4 bytes.
2646 * UTF-8 requires 1-3 bytes for every code point below 0x1000; otherwise 4 bytes.
2647 * UTF-EBCDIC requires 1-4 bytes for every code point below 0x1000; otherwise 4-5 bytes.
2648 *
2649 * These functions don't check for overflow. The worst case is every code
2650 * point in the input is 2 bytes, and requires 4 bytes on output. (If the code
2651 * is never going to run in EBCDIC, it is 2 bytes requiring 3 on output.) Therefore the
2652 * destination must be pre-extended to 2 times the source length.
2653 *
2654 * Do not use in-place. We optimize for native, for obvious reasons. */
a0ed51b3
LW
2655
2656U8*
dea0fc0b 2657Perl_utf16_to_utf8(pTHX_ U8* p, U8* d, I32 bytelen, I32 *newlen)
a0ed51b3 2658{
dea0fc0b
JH
2659 U8* pend;
2660 U8* dstart = d;
2661
7918f24d
NC
2662 PERL_ARGS_ASSERT_UTF16_TO_UTF8;
2663
dea0fc0b 2664 if (bytelen & 1)
56576a04
KW
2665 Perl_croak(aTHX_ "panic: utf16_to_utf8: odd bytelen %" UVuf,
2666 (UV)bytelen);
dea0fc0b
JH
2667
2668 pend = p + bytelen;
2669
a0ed51b3 2670 while (p < pend) {
dea0fc0b
JH
2671 UV uv = (p[0] << 8) + p[1]; /* UTF-16BE */
2672 p += 2;
2d1545e5 2673 if (OFFUNI_IS_INVARIANT(uv)) {
56d37426 2674 *d++ = LATIN1_TO_NATIVE((U8) uv);
a0ed51b3
LW
2675 continue;
2676 }
56d37426
KW
2677 if (uv <= MAX_UTF8_TWO_BYTE) {
2678 *d++ = UTF8_TWO_BYTE_HI(UNI_TO_NATIVE(uv));
2679 *d++ = UTF8_TWO_BYTE_LO(UNI_TO_NATIVE(uv));
a0ed51b3
LW
2680 continue;
2681 }
ffd0a9d3 2682
46956fad
KW
2683#define FIRST_HIGH_SURROGATE UNICODE_SURROGATE_FIRST
2684#define LAST_HIGH_SURROGATE 0xDBFF
2685#define FIRST_LOW_SURROGATE 0xDC00
2686#define LAST_LOW_SURROGATE UNICODE_SURROGATE_LAST
ffd0a9d3 2687#define FIRST_IN_PLANE1 0x10000
e23c50db
KW
2688
2689 /* This assumes that most uses will be in the first Unicode plane, not
2690 * needing surrogates */
2691 if (UNLIKELY(uv >= UNICODE_SURROGATE_FIRST
2692 && uv <= UNICODE_SURROGATE_LAST))
2693 {
2694 if (UNLIKELY(p >= pend) || UNLIKELY(uv > LAST_HIGH_SURROGATE)) {
2695 Perl_croak(aTHX_ "Malformed UTF-16 surrogate");
2696 }
2697 else {
01ea242b 2698 UV low = (p[0] << 8) + p[1];
e23c50db
KW
2699 if ( UNLIKELY(low < FIRST_LOW_SURROGATE)
2700 || UNLIKELY(low > LAST_LOW_SURROGATE))
2701 {
01ea242b 2702 Perl_croak(aTHX_ "Malformed UTF-16 surrogate");
e23c50db
KW
2703 }
2704 p += 2;
46956fad 2705 uv = ((uv - FIRST_HIGH_SURROGATE) << 10)
ffd0a9d3 2706 + (low - FIRST_LOW_SURROGATE) + FIRST_IN_PLANE1;
01ea242b 2707 }
a0ed51b3 2708 }
56d37426
KW
2709#ifdef EBCDIC
2710 d = uvoffuni_to_utf8_flags(d, uv, 0);
2711#else
ffd0a9d3 2712 if (uv < FIRST_IN_PLANE1) {
eb160463
GS
2713 *d++ = (U8)(( uv >> 12) | 0xe0);
2714 *d++ = (U8)(((uv >> 6) & 0x3f) | 0x80);
2715 *d++ = (U8)(( uv & 0x3f) | 0x80);
a0ed51b3
LW
2716 continue;
2717 }
2718 else {
eb160463
GS
2719 *d++ = (U8)(( uv >> 18) | 0xf0);
2720 *d++ = (U8)(((uv >> 12) & 0x3f) | 0x80);
2721 *d++ = (U8)(((uv >> 6) & 0x3f) | 0x80);
2722 *d++ = (U8)(( uv & 0x3f) | 0x80);
a0ed51b3
LW
2723 continue;
2724 }
56d37426 2725#endif
a0ed51b3 2726 }
dea0fc0b 2727 *newlen = d - dstart;
a0ed51b3
LW
2728 return d;
2729}
2730
2731/* Note: this one is slightly destructive of the source. */
2732
2733U8*
dea0fc0b 2734Perl_utf16_to_utf8_reversed(pTHX_ U8* p, U8* d, I32 bytelen, I32 *newlen)
a0ed51b3
LW
2735{
2736 U8* s = (U8*)p;
d4c19fe8 2737 U8* const send = s + bytelen;
7918f24d
NC
2738
2739 PERL_ARGS_ASSERT_UTF16_TO_UTF8_REVERSED;
2740
e0ea5e2d 2741 if (bytelen & 1)
147e3846 2742 Perl_croak(aTHX_ "panic: utf16_to_utf8_reversed: odd bytelen %" UVuf,
e0ea5e2d
NC
2743 (UV)bytelen);
2744
a0ed51b3 2745 while (s < send) {
d4c19fe8 2746 const U8 tmp = s[0];
a0ed51b3
LW
2747 s[0] = s[1];
2748 s[1] = tmp;
2749 s += 2;
2750 }
dea0fc0b 2751 return utf16_to_utf8(p, d, bytelen, newlen);
a0ed51b3
LW
2752}
2753
922e8cb4
KW
2754bool
2755Perl__is_uni_FOO(pTHX_ const U8 classnum, const UV c)
2756{
dc31b55c 2757 return _invlist_contains_cp(PL_XPosix_ptrs[classnum], c);
922e8cb4
KW
2758}
2759
f9ae8fb6
JD
2760/* Internal function so we can deprecate the external one, and call
2761 this one from other deprecated functions in this file */
2762
f2645549
KW
2763bool
2764Perl__is_utf8_idstart(pTHX_ const U8 *p)
61b19385 2765{
f2645549 2766 PERL_ARGS_ASSERT__IS_UTF8_IDSTART;
61b19385
KW
2767
2768 if (*p == '_')
2769 return TRUE;
af0d7385
KW
2770 return is_utf8_common(p, NULL,
2771 "This is buggy if this gets used",
2772 PL_utf8_idstart);
61b19385
KW
2773}
2774
5092f92a 2775bool
eba68aa0
KW
2776Perl__is_uni_perl_idcont(pTHX_ UV c)
2777{
c12658c9 2778 return _invlist_contains_cp(PL_utf8_perl_idcont, c);
eba68aa0
KW
2779}
2780
2781bool
f91dcd13
KW
2782Perl__is_uni_perl_idstart(pTHX_ UV c)
2783{
c12658c9 2784 return _invlist_contains_cp(PL_utf8_perl_idstart, c);
f91dcd13
KW
2785}
2786
3a4c58c9 2787UV
56576a04
KW
2788Perl__to_upper_title_latin1(pTHX_ const U8 c, U8* p, STRLEN *lenp,
2789 const char S_or_s)
3a4c58c9
KW
2790{
2791 /* We have the latin1-range values compiled into the core, so just use
4a4088c4 2792 * those, converting the result to UTF-8. The only difference between upper
3a4c58c9
KW
2793 * and title case in this range is that LATIN_SMALL_LETTER_SHARP_S is
2794 * either "SS" or "Ss". Which one to use is passed into the routine in
2795 * 'S_or_s' to avoid a test */
2796
2797 UV converted = toUPPER_LATIN1_MOD(c);
2798
2799 PERL_ARGS_ASSERT__TO_UPPER_TITLE_LATIN1;
2800
2801 assert(S_or_s == 'S' || S_or_s == 's');
2802
6f2d5cbc 2803 if (UVCHR_IS_INVARIANT(converted)) { /* No difference between the two for
f4cd282c 2804 characters in this range */
3a4c58c9
KW
2805 *p = (U8) converted;
2806 *lenp = 1;
2807 return converted;
2808 }
2809
2810 /* toUPPER_LATIN1_MOD gives the correct results except for three outliers,
2811 * which it maps to one of them, so as to only have to have one check for
2812 * it in the main case */
2813 if (UNLIKELY(converted == LATIN_SMALL_LETTER_Y_WITH_DIAERESIS)) {
2814 switch (c) {
2815 case LATIN_SMALL_LETTER_Y_WITH_DIAERESIS:
2816 converted = LATIN_CAPITAL_LETTER_Y_WITH_DIAERESIS;
2817 break;
2818 case MICRO_SIGN:
2819 converted = GREEK_CAPITAL_LETTER_MU;
2820 break;
79e064b9
KW
2821#if UNICODE_MAJOR_VERSION > 2 \
2822 || (UNICODE_MAJOR_VERSION == 2 && UNICODE_DOT_VERSION >= 1 \
2823 && UNICODE_DOT_DOT_VERSION >= 8)
3a4c58c9
KW
2824 case LATIN_SMALL_LETTER_SHARP_S:
2825 *(p)++ = 'S';
2826 *p = S_or_s;
2827 *lenp = 2;
2828 return 'S';
79e064b9 2829#endif
3a4c58c9 2830 default:
56576a04
KW
2831 Perl_croak(aTHX_ "panic: to_upper_title_latin1 did not expect"
2832 " '%c' to map to '%c'",
2833 c, LATIN_SMALL_LETTER_Y_WITH_DIAERESIS);
e5964223 2834 NOT_REACHED; /* NOTREACHED */
3a4c58c9
KW
2835 }
2836 }
2837
2838 *(p)++ = UTF8_TWO_BYTE_HI(converted);
2839 *p = UTF8_TWO_BYTE_LO(converted);
2840 *lenp = 2;
2841
2842 return converted;
2843}
2844
fe63c520
KW
2845/* If compiled on an early Unicode version, there may not be auxiliary tables
2846 * */
2847#ifndef HAS_UC_AUX_TABLES
2848# define UC_AUX_TABLE_ptrs NULL
2849# define UC_AUX_TABLE_lengths NULL
2850#endif
2851#ifndef HAS_TC_AUX_TABLES
2852# define TC_AUX_TABLE_ptrs NULL
2853# define TC_AUX_TABLE_lengths NULL
2854#endif
2855#ifndef HAS_LC_AUX_TABLES
2856# define LC_AUX_TABLE_ptrs NULL
2857# define LC_AUX_TABLE_lengths NULL
2858#endif
2859#ifndef HAS_CF_AUX_TABLES
2860# define CF_AUX_TABLE_ptrs NULL
2861# define CF_AUX_TABLE_lengths NULL
2862#endif
2863#ifndef HAS_UC_AUX_TABLES
2864# define UC_AUX_TABLE_ptrs NULL
2865# define UC_AUX_TABLE_lengths NULL
2866#endif
2867
50bda2c3
KW
2868/* Call the function to convert a UTF-8 encoded character to the specified case.
2869 * Note that there may be more than one character in the result.
6fa2f9bc
KW
2870 * 's' is a pointer to the first byte of the input character
2871 * 'd' will be set to the first byte of the string of changed characters. It
50bda2c3 2872 * needs to have space for UTF8_MAXBYTES_CASE+1 bytes
6fa2f9bc 2873 * 'lenp' will be set to the length in bytes of the string of changed characters
50bda2c3 2874 *
56576a04 2875 * The functions return the ordinal of the first character in the string of
6fa2f9bc 2876 * 'd' */
56576a04 2877#define CALL_UPPER_CASE(uv, s, d, lenp) \
8946fcd9
KW
2878 _to_utf8_case(uv, s, d, lenp, PL_utf8_toupper, \
2879 Uppercase_Mapping_invmap, \
2880 UC_AUX_TABLE_ptrs, \
2881 UC_AUX_TABLE_lengths, \
2882 "uppercase")
56576a04 2883#define CALL_TITLE_CASE(uv, s, d, lenp) \
8946fcd9
KW
2884 _to_utf8_case(uv, s, d, lenp, PL_utf8_totitle, \
2885 Titlecase_Mapping_invmap, \
2886 TC_AUX_TABLE_ptrs, \
2887 TC_AUX_TABLE_lengths, \
2888 "titlecase")
56576a04 2889#define CALL_LOWER_CASE(uv, s, d, lenp) \
8946fcd9
KW
2890 _to_utf8_case(uv, s, d, lenp, PL_utf8_tolower, \
2891 Lowercase_Mapping_invmap, \
2892 LC_AUX_TABLE_ptrs, \
2893 LC_AUX_TABLE_lengths, \
2894 "lowercase")
2895
50bda2c3 2896
b9992569
KW
2897/* This additionally has the input parameter 'specials', which if non-zero will
2898 * cause this to use the specials hash for folding (meaning get full case
50bda2c3 2899 * folding); otherwise, when zero, this implies a simple case fold */
56576a04 2900#define CALL_FOLD_CASE(uv, s, d, lenp, specials) \
8946fcd9
KW
2901 (specials) \
2902 ? _to_utf8_case(uv, s, d, lenp, PL_utf8_tofold, \
2903 Case_Folding_invmap, \
2904 CF_AUX_TABLE_ptrs, \
2905 CF_AUX_TABLE_lengths, \
2906 "foldcase") \
2907 : _to_utf8_case(uv, s, d, lenp, PL_utf8_tosimplefold, \
2908 Simple_Case_Folding_invmap, \
2909 NULL, NULL, \
2910 "foldcase")
c3fd2246 2911
84afefe6
JH
2912UV
2913Perl_to_uni_upper(pTHX_ UV c, U8* p, STRLEN *lenp)
a0ed51b3 2914{
a1433954
KW
2915 /* Convert the Unicode character whose ordinal is <c> to its uppercase
2916 * version and store that in UTF-8 in <p> and its length in bytes in <lenp>.
2917 * Note that the <p> needs to be at least UTF8_MAXBYTES_CASE+1 bytes since
c3fd2246
KW
2918 * the changed version may be longer than the original character.
2919 *
2920 * The ordinal of the first character of the changed version is returned
2921 * (but note, as explained above, that there may be more.) */
2922
7918f24d
NC
2923 PERL_ARGS_ASSERT_TO_UNI_UPPER;
2924
3a4c58c9
KW
2925 if (c < 256) {
2926 return _to_upper_title_latin1((U8) c, p, lenp, 'S');
2927 }
2928
0ebc6274 2929 uvchr_to_utf8(p, c);
b9992569 2930 return CALL_UPPER_CASE(c, p, p, lenp);
a0ed51b3
LW
2931}
2932
84afefe6
JH
2933UV
2934Perl_to_uni_title(pTHX_ UV c, U8* p, STRLEN *lenp)
a0ed51b3 2935{
7918f24d
NC
2936 PERL_ARGS_ASSERT_TO_UNI_TITLE;
2937
3a4c58c9
KW
2938 if (c < 256) {
2939 return _to_upper_title_latin1((U8) c, p, lenp, 's');
2940 }
2941
0ebc6274 2942 uvchr_to_utf8(p, c);
b9992569 2943 return CALL_TITLE_CASE(c, p, p, lenp);
a0ed51b3
LW
2944}
2945
afc16117 2946STATIC U8
eaf412bf 2947S_to_lower_latin1(const U8 c, U8* p, STRLEN *lenp, const char dummy)
afc16117
KW
2948{
2949 /* We have the latin1-range values compiled into the core, so just use
4a4088c4 2950 * those, converting the result to UTF-8. Since the result is always just
a1433954 2951 * one character, we allow <p> to be NULL */
afc16117
KW
2952
2953 U8 converted = toLOWER_LATIN1(c);
2954
eaf412bf
KW
2955 PERL_UNUSED_ARG(dummy);
2956
afc16117 2957 if (p != NULL) {
6f2d5cbc 2958 if (NATIVE_BYTE_IS_INVARIANT(converted)) {
afc16117
KW
2959 *p = converted;
2960 *lenp = 1;
2961 }
2962 else {
430c9760
KW
2963 /* Result is known to always be < 256, so can use the EIGHT_BIT
2964 * macros */
2965 *p = UTF8_EIGHT_BIT_HI(converted);
2966 *(p+1) = UTF8_EIGHT_BIT_LO(converted);
afc16117
KW
2967 *lenp = 2;
2968 }
2969 }
2970 return converted;
2971}
2972
84afefe6
JH
2973UV
2974Perl_to_uni_lower(pTHX_ UV c, U8* p, STRLEN *lenp)
a0ed51b3 2975{
7918f24d
NC
2976 PERL_ARGS_ASSERT_TO_UNI_LOWER;
2977
afc16117 2978 if (c < 256) {
eaf412bf 2979 return to_lower_latin1((U8) c, p, lenp, 0 /* 0 is a dummy arg */ );
bca00c02
KW
2980 }
2981
afc16117 2982 uvchr_to_utf8(p, c);
b9992569 2983 return CALL_LOWER_CASE(c, p, p, lenp);
a0ed51b3
LW
2984}
2985
84afefe6 2986UV
7c0ab950 2987Perl__to_fold_latin1(const U8 c, U8* p, STRLEN *lenp, const unsigned int flags)
a1dde8de 2988{
51910141 2989 /* Corresponds to to_lower_latin1(); <flags> bits meanings:
1ca267a5 2990 * FOLD_FLAGS_NOMIX_ASCII iff non-ASCII to ASCII folds are prohibited
51910141 2991 * FOLD_FLAGS_FULL iff full folding is to be used;
1ca267a5
KW
2992 *
2993 * Not to be used for locale folds
51910141 2994 */
f673fad4 2995
a1dde8de
KW
2996 UV converted;
2997
2998 PERL_ARGS_ASSERT__TO_FOLD_LATIN1;
2999
1ca267a5
KW
3000 assert (! (flags & FOLD_FLAGS_LOCALE));
3001
659a7c2d 3002 if (UNLIKELY(c == MICRO_SIGN)) {
a1dde8de
KW
3003 converted = GREEK_SMALL_LETTER_MU;
3004 }
9b63e895
KW
3005#if UNICODE_MAJOR_VERSION > 3 /* no multifolds in early Unicode */ \
3006 || (UNICODE_MAJOR_VERSION == 3 && ( UNICODE_DOT_VERSION > 0) \
3007 || UNICODE_DOT_DOT_VERSION > 0)
659a7c2d
KW
3008 else if ( (flags & FOLD_FLAGS_FULL)
3009 && UNLIKELY(c == LATIN_SMALL_LETTER_SHARP_S))
3010 {
1ca267a5
KW
3011 /* If can't cross 127/128 boundary, can't return "ss"; instead return
3012 * two U+017F characters, as fc("\df") should eq fc("\x{17f}\x{17f}")
3013 * under those circumstances. */
3014 if (flags & FOLD_FLAGS_NOMIX_ASCII) {
3015 *lenp = 2 * sizeof(LATIN_SMALL_LETTER_LONG_S_UTF8) - 2;
3016 Copy(LATIN_SMALL_LETTER_LONG_S_UTF8 LATIN_SMALL_LETTER_LONG_S_UTF8,
3017 p, *lenp, U8);
3018 return LATIN_SMALL_LETTER_LONG_S;
3019 }
3020 else {
4f489194
KW
3021 *(p)++ = 's';
3022 *p = 's';
3023 *lenp = 2;
3024 return 's';
1ca267a5 3025 }
a1dde8de 3026 }
9b63e895 3027#endif
a1dde8de
KW
3028 else { /* In this range the fold of all other characters is their lower
3029 case */
3030 converted = toLOWER_LATIN1(c);
3031 }
3032
6f2d5cbc 3033 if (UVCHR_IS_INVARIANT(converted)) {
a1dde8de
KW
3034 *p = (U8) converted;
3035 *lenp = 1;
3036 }
3037 else {
3038 *(p)++ = UTF8_TWO_BYTE_HI(converted);
3039 *p = UTF8_TWO_BYTE_LO(converted);
3040 *lenp = 2;
3041 }
3042
3043 return converted;
3044}
3045
3046UV
31f05a37 3047Perl__to_uni_fold_flags(pTHX_ UV c, U8* p, STRLEN *lenp, U8 flags)
84afefe6 3048{
4b593389 3049
a0270393
KW
3050 /* Not currently externally documented, and subject to change
3051 * <flags> bits meanings:
3052 * FOLD_FLAGS_FULL iff full folding is to be used;
31f05a37
KW
3053 * FOLD_FLAGS_LOCALE is set iff the rules from the current underlying
3054 * locale are to be used.
a0270393
KW
3055 * FOLD_FLAGS_NOMIX_ASCII iff non-ASCII to ASCII folds are prohibited
3056 */
4b593389 3057
36bb2ab6 3058 PERL_ARGS_ASSERT__TO_UNI_FOLD_FLAGS;
7918f24d 3059
780fcc9f 3060 if (flags & FOLD_FLAGS_LOCALE) {
8b7358b9
KW
3061 /* Treat a UTF-8 locale as not being in locale at all, except for
3062 * potentially warning */
3063 _CHECK_AND_WARN_PROBLEMATIC_LOCALE;
780fcc9f
KW
3064 if (IN_UTF8_CTYPE_LOCALE) {
3065 flags &= ~FOLD_FLAGS_LOCALE;
3066 }
3067 else {
e7b7ac46 3068 goto needs_full_generality;
780fcc9f 3069 }
31f05a37
KW
3070 }
3071
a1dde8de 3072 if (c < 256) {
e7b7ac46 3073 return _to_fold_latin1((U8) c, p, lenp,
31f05a37 3074 flags & (FOLD_FLAGS_FULL | FOLD_FLAGS_NOMIX_ASCII));
a1dde8de
KW
3075 }
3076
2f306ab9 3077 /* Here, above 255. If no special needs, just use the macro */
a0270393
KW
3078 if ( ! (flags & (FOLD_FLAGS_LOCALE|FOLD_FLAGS_NOMIX_ASCII))) {
3079 uvchr_to_utf8(p, c);
b9992569 3080 return CALL_FOLD_CASE(c, p, p, lenp, flags & FOLD_FLAGS_FULL);
a0270393 3081 }
567b353c 3082 else { /* Otherwise, _toFOLD_utf8_flags has the intelligence to deal with
a0270393
KW
3083 the special flags. */
3084 U8 utf8_c[UTF8_MAXBYTES + 1];
e7b7ac46
KW
3085
3086 needs_full_generality:
a0270393 3087 uvchr_to_utf8(utf8_c, c);
56576a04
KW
3088 return _toFOLD_utf8_flags(utf8_c, utf8_c + sizeof(utf8_c),
3089 p, lenp, flags);
a0270393 3090 }
84afefe6
JH
3091}
3092
26483009 3093PERL_STATIC_INLINE bool
5141f98e 3094S_is_utf8_common(pTHX_ const U8 *const p, SV **swash,
f25ce844 3095 const char *const swashname, SV* const invlist)
bde6a22d 3096{
ea317ccb
KW
3097 /* returns a boolean giving whether or not the UTF8-encoded character that
3098 * starts at <p> is in the swash indicated by <swashname>. <swash>
3099 * contains a pointer to where the swash indicated by <swashname>
3100 * is to be stored; which this routine will do, so that future calls will
f25ce844
KW
3101 * look at <*swash> and only generate a swash if it is not null. <invlist>
3102 * is NULL or an inversion list that defines the swash. If not null, it
3103 * saves time during initialization of the swash.
ea317ccb
KW
3104 *
3105 * Note that it is assumed that the buffer length of <p> is enough to
3106 * contain all the bytes that comprise the character. Thus, <*p> should
3107 * have been checked before this call for mal-formedness enough to assure
3108 * that. */
3109
7918f24d
NC
3110 PERL_ARGS_ASSERT_IS_UTF8_COMMON;
3111
492a624f 3112 /* The API should have included a length for the UTF-8 character in <p>,
28123549 3113 * but it doesn't. We therefore assume that p has been validated at least
492a624f
KW
3114 * as far as there being enough bytes available in it to accommodate the
3115 * character without reading beyond the end, and pass that number on to the
3116 * validating routine */
6302f837 3117 if (! isUTF8_CHAR(p, p + UTF8SKIP(p))) {
86ae6e94 3118 _force_out_malformed_utf8_message(p, p + UTF8SKIP(p),
99a765e9 3119 _UTF8_NO_CONFIDENCE_IN_CURLEN,
86ae6e94
KW
3120 1 /* Die */ );
3121 NOT_REACHED; /* NOTREACHED */
28123549 3122 }
86ae6e94 3123
dc31b55c
KW
3124 if (invlist) {
3125 return _invlist_contains_cp(invlist, valid_utf8_to_uvchr(p, NULL));
3126 }
3127
af0d7385
KW
3128 assert(swash);
3129
87367d5f
KW
3130 if (!*swash) {
3131 U8 flags = _CORE_SWASH_INIT_ACCEPT_INVLIST;
f25ce844
KW
3132 *swash = _core_swash_init("utf8",
3133
3134 /* Only use the name if there is no inversion
3135 * list; otherwise will go out to disk */
3136 (invlist) ? "" : swashname,
3137
3138 &PL_sv_undef, 1, 0, invlist, &flags);
87367d5f 3139 }
28123549 3140
bde6a22d
NC
3141 return swash_fetch(*swash, p, TRUE) != 0;
3142}
3143
da8c1a98 3144PERL_STATIC_INLINE bool
56576a04
KW
3145S_is_utf8_common_with_len(pTHX_ const U8 *const p, const U8 * const e,
3146 SV **swash, const char *const swashname,
3147 SV* const invlist)
da8c1a98
KW
3148{
3149 /* returns a boolean giving whether or not the UTF8-encoded character that
3150 * starts at <p>, and extending no further than <e - 1> is in the swash
3151 * indicated by <swashname>. <swash> contains a pointer to where the swash
3152 * indicated by <swashname> is to be stored; which this routine will do, so
3153 * that future calls will look at <*swash> and only generate a swash if it
3154 * is not null. <invlist> is NULL or an inversion list that defines the
3155 * swash. If not null, it saves time during initialization of the swash.
3156 */
3157
3158 PERL_ARGS_ASSERT_IS_UTF8_COMMON_WITH_LEN;
3159
3160 if (! isUTF8_CHAR(p, e)) {
3161 _force_out_malformed_utf8_message(p, e, 0, 1);
3162 NOT_REACHED; /* NOTREACHED */
3163 }
3164
dc31b55c
KW
3165 if (invlist) {
3166 return _invlist_contains_cp(invlist, valid_utf8_to_uvchr(p, NULL));
3167 }
3168
af0d7385
KW
3169 assert(swash);
3170
da8c1a98
KW
3171 if (!*swash) {
3172 U8 flags = _CORE_SWASH_INIT_ACCEPT_INVLIST;
3173 *swash = _core_swash_init("utf8",
3174
3175 /* Only use the name if there is no inversion
3176 * list; otherwise will go out to disk */
3177 (invlist) ? "" : swashname,
3178
3179 &PL_sv_undef, 1, 0, invlist, &flags);
3180 }
3181
3182 return swash_fetch(*swash, p, TRUE) != 0;
3183}
3184
34aeb2e9
KW
3185STATIC void
3186S_warn_on_first_deprecated_use(pTHX_ const char * const name,
3187 const char * const alternative,
3188 const bool use_locale,
3189 const char * const file,
3190 const unsigned line)
3191{
3192 const char * key;
3193
3194 PERL_ARGS_ASSERT_WARN_ON_FIRST_DEPRECATED_USE;
3195
3196 if (ckWARN_d(WARN_DEPRECATED)) {
3197
3198 key = Perl_form(aTHX_ "%s;%d;%s;%d", name, use_locale, file, line);
3199 if (! hv_fetch(PL_seen_deprecated_macro, key, strlen(key), 0)) {
3200 if (! PL_seen_deprecated_macro) {
3201 PL_seen_deprecated_macro = newHV();
3202 }
3203 if (! hv_store(PL_seen_deprecated_macro, key,
3204 strlen(key), &PL_sv_undef, 0))
3205 {
3206 Perl_croak(aTHX_ "panic: hv_store() unexpectedly failed");
3207 }
3208
c44e9413 3209 if (instr(file, "mathoms.c")) {
607313a1
KW
3210 Perl_warner(aTHX_ WARN_DEPRECATED,
3211 "In %s, line %d, starting in Perl v5.30, %s()"
3212 " will be removed. Avoid this message by"
3213 " converting to use %s().\n",
3214 file, line, name, alternative);
3215 }
3216 else {
34aeb2e9
KW
3217 Perl_warner(aTHX_ WARN_DEPRECATED,
3218 "In %s, line %d, starting in Perl v5.30, %s() will"
3219 " require an additional parameter. Avoid this"
3220 " message by converting to use %s().\n",
3221 file, line, name, alternative);
607313a1 3222 }
34aeb2e9
KW
3223 }
3224 }
3225}
3226
bde6a22d 3227bool
34aeb2e9 3228Perl__is_utf8_FOO(pTHX_ U8 classnum,
be99e2c2 3229 const U8 * const p,
34aeb2e9
KW
3230 const char * const name,
3231 const char * const alternative,
3232 const bool use_utf8,
3233 const bool use_locale,
3234 const char * const file,
3235 const unsigned line)
922e8cb4 3236{
922e8cb4
KW
3237 PERL_ARGS_ASSERT__IS_UTF8_FOO;
3238
34aeb2e9
KW
3239 warn_on_first_deprecated_use(name, alternative, use_locale, file, line);
3240
3241 if (use_utf8 && UTF8_IS_ABOVE_LATIN1(*p)) {
34aeb2e9
KW
3242
3243 switch (classnum) {
3244 case _CC_WORDCHAR:
3245 case _CC_DIGIT:
3246 case _CC_ALPHA:
3247 case _CC_LOWER:
3248 case _CC_UPPER:
3249 case _CC_PUNCT:
3250 case _CC_PRINT:
3251 case _CC_ALPHANUMERIC:
3252 case _CC_GRAPH:
3253 case _CC_CASED:
3254
3255 return is_utf8_common(p,
af0d7385
KW
3256 NULL,
3257 "This is buggy if this gets used",
34aeb2e9
KW
3258 PL_XPosix_ptrs[classnum]);
3259
3260 case _CC_SPACE:
3261 return is_XPERLSPACE_high(p);
3262 case _CC_BLANK:
3263 return is_HORIZWS_high(p);
3264 case _CC_XDIGIT:
3265 return is_XDIGIT_high(p);
3266 case _CC_CNTRL:
3267 return 0;
3268 case _CC_ASCII:
3269 return 0;
3270 case _CC_VERTSPACE:
3271 return is_VERTWS_high(p);
3272 case _CC_IDFIRST:
af0d7385
KW
3273 return is_utf8_common(p, NULL,
3274 "This is buggy if this gets used",
3275 PL_utf8_perl_idstart);
34aeb2e9 3276 case _CC_IDCONT:
af0d7385
KW
3277 return is_utf8_common(p, NULL,
3278 "This is buggy if this gets used",
3279 PL_utf8_perl_idcont);
34aeb2e9
KW
3280 }
3281 }
3282
3283 /* idcont is the same as wordchar below 256 */
3284 if (classnum == _CC_IDCONT) {
3285 classnum = _CC_WORDCHAR;
3286 }
3287 else if (classnum == _CC_IDFIRST) {
3288 if (*p == '_') {
3289 return TRUE;
3290 }
3291 classnum = _CC_ALPHA;
3292 }
3293
3294 if (! use_locale) {
3295 if (! use_utf8 || UTF8_IS_INVARIANT(*p)) {
3296 return _generic_isCC(*p, classnum);
3297 }
922e8cb4 3298
34aeb2e9
KW
3299 return _generic_isCC(EIGHT_BIT_UTF8_TO_NATIVE(*p, *(p + 1 )), classnum);
3300 }
3301 else {
3302 if (! use_utf8 || UTF8_IS_INVARIANT(*p)) {
3303 return isFOO_lc(classnum, *p);
3304 }
3305
3306 return isFOO_lc(classnum, EIGHT_BIT_UTF8_TO_NATIVE(*p, *(p + 1 )));
3307 }
3308
3309 NOT_REACHED; /* NOTREACHED */
922e8cb4
KW
3310}
3311
3312bool
da8c1a98
KW
3313Perl__is_utf8_FOO_with_len(pTHX_ const U8 classnum, const U8 *p,
3314 const U8 * const e)
3315{
3316 PERL_ARGS_ASSERT__IS_UTF8_FOO_WITH_LEN;
3317
af0d7385
KW
3318 return is_utf8_common_with_len(p, e, NULL,
3319 "This is buggy if this gets used",
da8c1a98
KW
3320 PL_XPosix_ptrs[classnum]);
3321}
3322
3323bool
da8c1a98
KW
3324Perl__is_utf8_perl_idstart_with_len(pTHX_ const U8 *p, const U8 * const e)
3325{
da8c1a98
KW
3326 PERL_ARGS_ASSERT__IS_UTF8_PERL_IDSTART_WITH_LEN;
3327
af0d7385
KW
3328 return is_utf8_common_with_len(p, e, NULL,
3329 "This is buggy if this gets used",
3330 PL_utf8_perl_idstart);
da8c1a98
KW
3331}
3332
3333bool
f2645549 3334Perl__is_utf8_xidstart(pTHX_ const U8 *p)
c11ff943 3335{
f2645549 3336 PERL_ARGS_ASSERT__IS_UTF8_XIDSTART;
c11ff943
KW
3337
3338 if (*p == '_')
3339 return TRUE;
f25ce844 3340 return is_utf8_common(p, &PL_utf8_xidstart, "XIdStart", NULL);
c11ff943
KW
3341}
3342
3343bool
da8c1a98
KW
3344Perl__is_utf8_perl_idcont_with_len(pTHX_ const U8 *p, const U8 * const e)
3345{
da8c1a98
KW
3346 PERL_ARGS_ASSERT__IS_UTF8_PERL_IDCONT_WITH_LEN;
3347
af0d7385
KW
3348 return is_utf8_common_with_len(p, e, NULL,
3349 "This is buggy if this gets used",
3350 PL_utf8_perl_idcont);
da8c1a98
KW
3351}
3352
3353bool
f2645549 3354Perl__is_utf8_idcont(pTHX_ const U8 *p)
82686b01 3355{
f2645549 3356 PERL_ARGS_ASSERT__IS_UTF8_IDCONT;
7918f24d 3357
f25ce844 3358 return is_utf8_common(p, &PL_utf8_idcont, "IdContinue", NULL);
a0ed51b3
LW
3359}
3360
3361bool
f2645549 3362Perl__is_utf8_xidcont(pTHX_ const U8 *p)
c11ff943 3363{
f2645549 3364 PERL_ARGS_ASSERT__IS_UTF8_XIDCONT;
c11ff943 3365
5062866a 3366 return is_utf8_common(p, &PL_utf8_xidcont, "XIdContinue", NULL);
c11ff943
KW
3367}
3368
3369bool
7dbf68d2
KW
3370Perl__is_utf8_mark(pTHX_ const U8 *p)
3371{
7dbf68d2
KW
3372 PERL_ARGS_ASSERT__IS_UTF8_MARK;
3373
f25ce844 3374 return is_utf8_common(p, &PL_utf8_mark, "IsM", NULL);
7dbf68d2
KW
3375}
3376
6a4a25f4 3377STATIC UV
30613bdc
KW
3378S__to_utf8_case(pTHX_ const UV uv1, const U8 *p,
3379 U8* ustrp, STRLEN *lenp,
341bb5b7 3380 SV *invlist, const int * const invmap,
e39a4130 3381 const unsigned int * const * const aux_tables,
30613bdc
KW
3382 const U8 * const aux_table_lengths,
3383 const char * const normal)
b9992569 3384{
0134edef 3385 STRLEN len = 0;
7918f24d 3386
30613bdc
KW
3387 /* Change the case of code point 'uv1' whose UTF-8 representation (assumed
3388 * by this routine to be valid) begins at 'p'. 'normal' is a string to use
3389 * to name the new case in any generated messages, as a fallback if the
3390 * operation being used is not available. The new case is given by the
3391 * data structures in the remaining arguments.
3392 *
3393 * On return 'ustrp' points to '*lenp' UTF-8 encoded bytes representing the
3394 * entire changed case string, and the return value is the first code point
3395 * in that string */
3396
b9992569 3397 PERL_ARGS_ASSERT__TO_UTF8_CASE;
7918f24d 3398
36eaa811
KW
3399 /* For code points that don't change case, we already know that the output
3400 * of this function is the unchanged input, so we can skip doing look-ups
3401 * for them. Unfortunately the case-changing code points are scattered
3402 * around. But there are some long consecutive ranges where there are no
3403 * case changing code points. By adding tests, we can eliminate the lookup
3404 * for all the ones in such ranges. This is currently done here only for
3405 * just a few cases where the scripts are in common use in modern commerce
3406 * (and scripts adjacent to those which can be included without additional
3407 * tests). */
3408
3409 if (uv1 >= 0x0590) {
3410 /* This keeps from needing further processing the code points most
3411 * likely to be used in the following non-cased scripts: Hebrew,
3412 * Arabic, Syriac, Thaana, NKo, Samaritan, Mandaic, Devanagari,
3413 * Bengali, Gurmukhi, Gujarati, Oriya, Tamil, Telugu, Kannada,
3414 * Malayalam, Sinhala, Thai, Lao, Tibetan, Myanmar */
3415 if (uv1 < 0x10A0) {
3416 goto cases_to_self;
3417 }
3418
3419 /* The following largish code point ranges also don't have case
3420 * changes, but khw didn't think they warranted extra tests to speed
3421 * them up (which would slightly slow down everything else above them):
3422 * 1100..139F Hangul Jamo, Ethiopic
3423 * 1400..1CFF Unified Canadian Aboriginal Syllabics, Ogham, Runic,
3424 * Tagalog, Hanunoo, Buhid, Tagbanwa, Khmer, Mongolian,
3425 * Limbu, Tai Le, New Tai Lue, Buginese, Tai Tham,
3426 * Combining Diacritical Marks Extended, Balinese,
3427 * Sundanese, Batak, Lepcha, Ol Chiki
3428 * 2000..206F General Punctuation
3429 */
3430
3431 if (uv1 >= 0x2D30) {
3432
3433 /* This keeps the from needing further processing the code points
3434 * most likely to be used in the following non-cased major scripts:
3435 * CJK, Katakana, Hiragana, plus some less-likely scripts.
3436 *
3437 * (0x2D30 above might have to be changed to 2F00 in the unlikely
3438 * event that Unicode eventually allocates the unused block as of
3439 * v8.0 2FE0..2FEF to code points that are cased. khw has verified
3440 * that the test suite will start having failures to alert you
3441 * should that happen) */
3442 if (uv1 < 0xA640) {
3443 goto cases_to_self;
3444 }
3445
3446 if (uv1 >= 0xAC00) {
3447 if (UNLIKELY(UNICODE_IS_SURROGATE(uv1))) {
5af9bc97
KW
3448 if (ckWARN_d(WARN_SURROGATE)) {
3449 const char* desc = (PL_op) ? OP_DESC(PL_op) : normal;
3450 Perl_warner(aTHX_ packWARN(WARN_SURROGATE),
56576a04
KW
3451 "Operation \"%s\" returns its argument for"
3452 " UTF-16 surrogate U+%04" UVXf, desc, uv1);
5af9bc97
KW
3453 }
3454 goto cases_to_self;
3455 }
36eaa811
KW
3456
3457 /* AC00..FAFF Catches Hangul syllables and private use, plus
3458 * some others */
3459 if (uv1 < 0xFB00) {
3460 goto cases_to_self;
36eaa811
KW
3461 }
3462
5af9bc97 3463 if (UNLIKELY(UNICODE_IS_SUPER(uv1))) {
d22ec717
KW
3464 if (UNLIKELY(uv1 > MAX_EXTERNALLY_LEGAL_CP)) {
3465 Perl_croak(aTHX_ cp_above_legal_max, uv1,
3466 MAX_EXTERNALLY_LEGAL_CP);
5af9bc97
KW
3467 }
3468 if (ckWARN_d(WARN_NON_UNICODE)) {
3469 const char* desc = (PL_op) ? OP_DESC(PL_op) : normal;
3470 Perl_warner(aTHX_ packWARN(WARN_NON_UNICODE),
56576a04
KW
3471 "Operation \"%s\" returns its argument for"
3472 " non-Unicode code point 0x%04" UVXf, desc, uv1);
5af9bc97
KW
3473 }
3474 goto cases_to_self;
3475 }
3bfc1e70
KW
3476#ifdef HIGHEST_CASE_CHANGING_CP_FOR_USE_ONLY_BY_UTF8_DOT_C
3477 if (UNLIKELY(uv1
3478 > HIGHEST_CASE_CHANGING_CP_FOR_USE_ONLY_BY_UTF8_DOT_C))
3479 {
3480
56576a04
KW
3481 /* As of Unicode 10.0, this means we avoid swash creation
3482 * for anything beyond high Plane 1 (below emojis) */
3bfc1e70
KW
3483 goto cases_to_self;
3484 }
3485#endif
36eaa811
KW
3486 }
3487 }
9ae3ac1a 3488
36eaa811 3489 /* Note that non-characters are perfectly legal, so no warning should
8946fcd9 3490 * be given. */
9ae3ac1a
KW
3491 }
3492
8946fcd9
KW
3493 {
3494 unsigned int i;
e39a4130 3495 const unsigned int * cp_list;
8946fcd9
KW
3496 U8 * d;
3497 SSize_t index = _invlist_search(invlist, uv1);
3498 IV base = invmap[index];
0134edef 3499
30613bdc
KW
3500 /* The data structures are set up so that if 'base' is non-negative,
3501 * the case change is 1-to-1; and if 0, the change is to itself */
8946fcd9
KW
3502 if (base >= 0) {
3503 IV lc;
b08cf34e 3504
8946fcd9
KW
3505 if (base == 0) {
3506 goto cases_to_self;
4a8240a3 3507 }
4a8240a3 3508
30613bdc 3509 /* This computes, e.g. lc(H) as 'H - A + a', using the lc table */
8946fcd9
KW
3510 lc = base + uv1 - invlist_array(invlist)[index];
3511 *lenp = uvchr_to_utf8(ustrp, lc) - ustrp;
3512 return lc;
3513 }
1feea2c7 3514
30613bdc
KW
3515 /* Here 'base' is negative. That means the mapping is 1-to-many, and
3516 * requires an auxiliary table look up. abs(base) gives the index into
3517 * a list of such tables which points to the proper aux table. And a
3518 * parallel list gives the length of each corresponding aux table. */
8946fcd9 3519 cp_list = aux_tables[-base];
30613bdc
KW
3520
3521 /* Create the string of UTF-8 from the mapped-to code points */
8946fcd9
KW
3522 d = ustrp;
3523 for (i = 0; i < aux_table_lengths[-base]; i++) {
3524 d = uvchr_to_utf8(d, cp_list[i]);
cbe07460 3525 }
8946fcd9
KW
3526 *d = '\0';
3527 *lenp = d - ustrp;
3528
3529 return cp_list[0];
cbe07460
KW
3530 }
3531
3532 /* Here, there was no mapping defined, which means that the code point maps
3533 * to itself. Return the inputs */
e24dfe9c 3534 cases_to_self:
bfdf22ec 3535 len = UTF8SKIP(p);
ca9fab46
KW
3536 if (p != ustrp) { /* Don't copy onto itself */
3537 Copy(p, ustrp, len, U8);
3538 }
0134edef 3539
c404ed8c 3540 *lenp = len;
2a37f04d 3541
f4cd282c 3542 return uv1;
cbe07460 3543
a0ed51b3
LW
3544}
3545
b74fe592 3546Size_t
e39a4130
KW
3547Perl__inverse_folds(pTHX_ const UV cp, unsigned int * first_folds_to,
3548 const unsigned int ** remaining_folds_to)
b74fe592
KW
3549{
3550 /* Returns the count of the number of code points that fold to the input
3551 * 'cp' (besides itself).
3552 *
3553 * If the return is 0, there is nothing else that folds to it, and
3554 * '*first_folds_to' is set to 0, and '*remaining_folds_to' is set to NULL.
3555 *
3556 * If the return is 1, '*first_folds_to' is set to the single code point,
3557 * and '*remaining_folds_to' is set to NULL.
3558 *
3559 * Otherwise, '*first_folds_to' is set to a code point, and
3560 * '*remaining_fold_to' is set to an array that contains the others. The
3561 * length of this array is the returned count minus 1.
3562 *
3563 * The reason for this convolution is to avoid having to deal with
3564 * allocating and freeing memory. The lists are already constructed, so
3565 * the return can point to them, but single code points aren't, so would
3566 * need to be constructed if we didn't employ something like this API */
3567
3568 SSize_t index = _invlist_search(PL_utf8_foldclosures, cp);
3569 int base = _Perl_IVCF_invmap[index];
3570
3571 PERL_ARGS_ASSERT__INVERSE_FOLDS;
3572
3573 if (base == 0) { /* No fold */
3574 *first_folds_to = 0;
3575 *remaining_folds_to = NULL;
3576 return 0;
3577 }
3578
3579#ifndef HAS_IVCF_AUX_TABLES /* This Unicode version only has 1-1 folds */
3580
3581 assert(base > 0);
3582
3583#else
3584
3585 if (UNLIKELY(base < 0)) { /* Folds to more than one character */
3586
3587 /* The data structure is set up so that the absolute value of 'base' is
3588 * an index into a table of pointers to arrays, with the array
3589 * corresponding to the index being the list of code points that fold
3590 * to 'cp', and the parallel array containing the length of the list
3591 * array */
3592 *first_folds_to = IVCF_AUX_TABLE_ptrs[-base][0];
3593 *remaining_folds_to = IVCF_AUX_TABLE_ptrs[-base] + 1; /* +1 excludes
3594 *first_folds_to
3595 */
3596 return IVCF_AUX_TABLE_lengths[-base];
3597 }
3598
3599#endif
3600
3601 /* Only the single code point. This works like 'fc(G) = G - A + a' */
3602 *first_folds_to = base + cp - invlist_array(PL_utf8_foldclosures)[index];
3603 *remaining_folds_to = NULL;
3604 return 1;
3605}
3606
051a06d4 3607STATIC UV
56576a04
KW
3608S_check_locale_boundary_crossing(pTHX_ const U8* const p, const UV result,
3609 U8* const ustrp, STRLEN *lenp)
051a06d4 3610{
4a4088c4 3611 /* This is called when changing the case of a UTF-8-encoded character above
31f05a37
KW
3612 * the Latin1 range, and the operation is in a non-UTF-8 locale. If the
3613 * result contains a character that crosses the 255/256 boundary, disallow
3614 * the change, and return the original code point. See L<perlfunc/lc> for
3615 * why;
051a06d4 3616 *
a1433954
KW
3617 * p points to the original string whose case was changed; assumed
3618 * by this routine to be well-formed
051a06d4 3619 * result the code point of the first character in the changed-case string
56576a04
KW
3620 * ustrp points to the changed-case string (<result> represents its
3621 * first char)
051a06d4
KW
3622 * lenp points to the length of <ustrp> */
3623
3624 UV original; /* To store the first code point of <p> */
3625
3626 PERL_ARGS_ASSERT_CHECK_LOCALE_BOUNDARY_CROSSING;
3627
a4f12ed7 3628 assert(UTF8_IS_ABOVE_LATIN1(*p));
051a06d4
KW
3629
3630 /* We know immediately if the first character in the string crosses the
5e45c680 3631 * boundary, so can skip testing */
051a06d4
KW
3632 if (result > 255) {
3633
3634 /* Look at every character in the result; if any cross the
3635 * boundary, the whole thing is disallowed */
3636 U8* s = ustrp + UTF8SKIP(ustrp);
3637 U8* e = ustrp + *lenp;
3638 while (s < e) {
a4f12ed7 3639 if (! UTF8_IS_ABOVE_LATIN1(*s)) {
051a06d4
KW
3640 goto bad_crossing;
3641 }
3642 s += UTF8SKIP(s);
3643 }
3644
613abc6d
KW
3645 /* Here, no characters crossed, result is ok as-is, but we warn. */
3646 _CHECK_AND_OUTPUT_WIDE_LOCALE_UTF8_MSG(p, p + UTF8SKIP(p));
051a06d4
KW
3647 return result;
3648 }
3649
7b52d656 3650 bad_crossing:
051a06d4
KW
3651
3652 /* Failed, have to return the original */
4b88fb76 3653 original = valid_utf8_to_uvchr(p, lenp);
ab0b796c
KW
3654
3655 /* diag_listed_as: Can't do %s("%s") on non-UTF-8 locale; resolved to "%s". */
3656 Perl_ck_warner(aTHX_ packWARN(WARN_LOCALE),
56576a04
KW
3657 "Can't do %s(\"\\x{%" UVXf "}\") on non-UTF-8"
3658 " locale; resolved to \"\\x{%" UVXf "}\".",
357aadde 3659 OP_DESC(PL_op),
ab0b796c
KW
3660 original,
3661 original);
051a06d4
KW
3662 Copy(p, ustrp, *lenp, char);
3663 return original;
3664}
3665
607313a1
KW
3666STATIC U32
3667S_check_and_deprecate(pTHX_ const U8 *p,
3668 const U8 **e,
3669 const unsigned int type, /* See below */
3670 const bool use_locale, /* Is this a 'LC_'
3671 macro call? */
3672 const char * const file,
3673 const unsigned line)
3674{
3675 /* This is a temporary function to deprecate the unsafe calls to the case
3676 * changing macros and functions. It keeps all the special stuff in just
3677 * one place.
3678 *
3679 * It updates *e with the pointer to the end of the input string. If using
3680 * the old-style macros, *e is NULL on input, and so this function assumes
3681 * the input string is long enough to hold the entire UTF-8 sequence, and
3682 * sets *e accordingly, but it then returns a flag to pass the
3683 * utf8n_to_uvchr(), to tell it that this size is a guess, and to avoid
3684 * using the full length if possible.
3685 *
3686 * It also does the assert that *e > p when *e is not NULL. This should be
3687 * migrated to the callers when this function gets deleted.
3688 *
3689 * The 'type' parameter is used for the caller to specify which case
3690 * changing function this is called from: */
3691
3692# define DEPRECATE_TO_UPPER 0
3693# define DEPRECATE_TO_TITLE 1
3694# define DEPRECATE_TO_LOWER 2
3695# define DEPRECATE_TO_FOLD 3
3696
3697 U32 utf8n_flags = 0;
3698 const char * name;
3699 const char * alternative;
3700
3701 PERL_ARGS_ASSERT_CHECK_AND_DEPRECATE;
3702
3703 if (*e == NULL) {
3704 utf8n_flags = _UTF8_NO_CONFIDENCE_IN_CURLEN;
3705 *e = p + UTF8SKIP(p);
3706
3707 /* For mathoms.c calls, we use the function name we know is stored
c44e9413 3708 * there. It could be part of a larger path */
607313a1 3709 if (type == DEPRECATE_TO_UPPER) {
c44e9413 3710 name = instr(file, "mathoms.c")
607313a1
KW
3711 ? "to_utf8_upper"
3712 : "toUPPER_utf8";
3713 alternative = "toUPPER_utf8_safe";
3714 }
3715 else if (type == DEPRECATE_TO_TITLE) {
c44e9413 3716 name = instr(file, "mathoms.c")
607313a1
KW
3717 ? "to_utf8_title"
3718 : "toTITLE_utf8";
3719 alternative = "toTITLE_utf8_safe";
3720 }
3721 else if (type == DEPRECATE_TO_LOWER) {
c44e9413 3722 name = instr(file, "mathoms.c")
607313a1
KW
3723 ? "to_utf8_lower"
3724 : "toLOWER_utf8";
3725 alternative = "toLOWER_utf8_safe";
3726 }
3727 else if (type == DEPRECATE_TO_FOLD) {
c44e9413 3728 name = instr(file, "mathoms.c")