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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
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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"
a0ed51b3 35
806547a7 36static const char malformed_text[] = "Malformed UTF-8 character";
27da23d5 37static const char unees[] =
806547a7 38 "Malformed UTF-8 character (unexpected end of string)";
760c7c2f 39static const char cp_above_legal_max[] =
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40 "Use of code point 0x%" UVXf " is not allowed; the"
41 " permissible max is 0x%" UVXf;
760c7c2f 42
d22ec717 43#define MAX_EXTERNALLY_LEGAL_CP ((UV) (IV_MAX))
901b21bf 44
48ef279e 45/*
ccfc67b7 46=head1 Unicode Support
7fefc6c1 47These are various utility functions for manipulating UTF8-encoded
72d33970 48strings. For the uninitiated, this is a method of representing arbitrary
61296642 49Unicode characters as a variable number of bytes, in such a way that
56da48f7
DM
50characters in the ASCII range are unmodified, and a zero byte never appears
51within non-zero characters.
166f8a29 52
eaf7a4d2
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53=cut
54*/
55
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56void
57Perl__force_out_malformed_utf8_message(pTHX_
58 const U8 *const p, /* First byte in UTF-8 sequence */
59 const U8 * const e, /* Final byte in sequence (may include
60 multiple chars */
61 const U32 flags, /* Flags to pass to utf8n_to_uvchr(),
62 usually 0, or some DISALLOW flags */
63 const bool die_here) /* If TRUE, this function does not return */
64{
65 /* This core-only function is to be called when a malformed UTF-8 character
66 * is found, in order to output the detailed information about the
67 * malformation before dieing. The reason it exists is for the occasions
68 * when such a malformation is fatal, but warnings might be turned off, so
69 * that normally they would not be actually output. This ensures that they
70 * do get output. Because a sequence may be malformed in more than one
71 * way, multiple messages may be generated, so we can't make them fatal, as
72 * that would cause the first one to die.
73 *
74 * Instead we pretend -W was passed to perl, then die afterwards. The
75 * flexibility is here to return to the caller so they can finish up and
76 * die themselves */
77 U32 errors;
78
79 PERL_ARGS_ASSERT__FORCE_OUT_MALFORMED_UTF8_MESSAGE;
80
81 ENTER;
c15a80f3 82 SAVEI8(PL_dowarn);
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83 SAVESPTR(PL_curcop);
84
85 PL_dowarn = G_WARN_ALL_ON|G_WARN_ON;
86 if (PL_curcop) {
87 PL_curcop->cop_warnings = pWARN_ALL;
88 }
89
90 (void) utf8n_to_uvchr_error(p, e - p, NULL, flags & ~UTF8_CHECK_ONLY, &errors);
91
92 LEAVE;
93
94 if (! errors) {
95 Perl_croak(aTHX_ "panic: _force_out_malformed_utf8_message should"
96 " be called only when there are errors found");
97 }
98
99 if (die_here) {
100 Perl_croak(aTHX_ "Malformed UTF-8 character (fatal)");
101 }
102}
103
eaf7a4d2 104/*
378516de 105=for apidoc uvoffuni_to_utf8_flags
eebe1485 106
a27992cc 107THIS FUNCTION SHOULD BE USED IN ONLY VERY SPECIALIZED CIRCUMSTANCES.
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108Instead, B<Almost all code should use L</uvchr_to_utf8> or
109L</uvchr_to_utf8_flags>>.
a27992cc 110
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111This function is like them, but the input is a strict Unicode
112(as opposed to native) code point. Only in very rare circumstances should code
113not be using the native code point.
949cf498 114
efa9cd84 115For details, see the description for L</uvchr_to_utf8_flags>.
949cf498 116
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117=cut
118*/
119
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120/* All these formats take a single UV code point argument */
121const char surrogate_cp_format[] = "UTF-16 surrogate U+%04" UVXf;
122const char nonchar_cp_format[] = "Unicode non-character U+%04" UVXf
123 " is not recommended for open interchange";
124const char super_cp_format[] = "Code point 0x%" UVXf " is not Unicode,"
125 " may not be portable";
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126const char perl_extended_cp_format[] = "Code point 0x%" UVXf " is not" \
127 " Unicode, requires a Perl extension," \
128 " and so is not portable";
c94c2f39 129
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130#define HANDLE_UNICODE_SURROGATE(uv, flags) \
131 STMT_START { \
132 if (flags & UNICODE_WARN_SURROGATE) { \
133 Perl_ck_warner_d(aTHX_ packWARN(WARN_SURROGATE), \
c94c2f39 134 surrogate_cp_format, uv); \
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135 } \
136 if (flags & UNICODE_DISALLOW_SURROGATE) { \
137 return NULL; \
138 } \
139 } STMT_END;
140
141#define HANDLE_UNICODE_NONCHAR(uv, flags) \
142 STMT_START { \
143 if (flags & UNICODE_WARN_NONCHAR) { \
144 Perl_ck_warner_d(aTHX_ packWARN(WARN_NONCHAR), \
c94c2f39 145 nonchar_cp_format, uv); \
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146 } \
147 if (flags & UNICODE_DISALLOW_NONCHAR) { \
148 return NULL; \
149 } \
150 } STMT_END;
151
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152/* Use shorter names internally in this file */
153#define SHIFT UTF_ACCUMULATION_SHIFT
154#undef MARK
155#define MARK UTF_CONTINUATION_MARK
156#define MASK UTF_CONTINUATION_MASK
157
dfe13c55 158U8 *
4b31b634 159Perl_uvoffuni_to_utf8_flags(pTHX_ U8 *d, UV uv, const UV flags)
a0ed51b3 160{
378516de 161 PERL_ARGS_ASSERT_UVOFFUNI_TO_UTF8_FLAGS;
7918f24d 162
2d1545e5 163 if (OFFUNI_IS_INVARIANT(uv)) {
4c8cd605 164 *d++ = LATIN1_TO_NATIVE(uv);
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165 return d;
166 }
facc1dc2 167
3ea68d71 168 if (uv <= MAX_UTF8_TWO_BYTE) {
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169 *d++ = I8_TO_NATIVE_UTF8(( uv >> SHIFT) | UTF_START_MARK(2));
170 *d++ = I8_TO_NATIVE_UTF8(( uv & MASK) | MARK);
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171 return d;
172 }
d9432125 173
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174 /* Not 2-byte; test for and handle 3-byte result. In the test immediately
175 * below, the 16 is for start bytes E0-EF (which are all the possible ones
176 * for 3 byte characters). The 2 is for 2 continuation bytes; these each
177 * contribute SHIFT bits. This yields 0x4000 on EBCDIC platforms, 0x1_0000
178 * on ASCII; so 3 bytes covers the range 0x400-0x3FFF on EBCDIC;
179 * 0x800-0xFFFF on ASCII */
180 if (uv < (16 * (1U << (2 * SHIFT)))) {
181 *d++ = I8_TO_NATIVE_UTF8(( uv >> ((3 - 1) * SHIFT)) | UTF_START_MARK(3));
182 *d++ = I8_TO_NATIVE_UTF8(((uv >> ((2 - 1) * SHIFT)) & MASK) | MARK);
183 *d++ = I8_TO_NATIVE_UTF8(( uv /* (1 - 1) */ & MASK) | MARK);
184
185#ifndef EBCDIC /* These problematic code points are 4 bytes on EBCDIC, so
186 aren't tested here */
187 /* The most likely code points in this range are below the surrogates.
188 * Do an extra test to quickly exclude those. */
189 if (UNLIKELY(uv >= UNICODE_SURROGATE_FIRST)) {
190 if (UNLIKELY( UNICODE_IS_32_CONTIGUOUS_NONCHARS(uv)
191 || UNICODE_IS_END_PLANE_NONCHAR_GIVEN_NOT_SUPER(uv)))
192 {
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193 HANDLE_UNICODE_NONCHAR(uv, flags);
194 }
195 else if (UNLIKELY(UNICODE_IS_SURROGATE(uv))) {
196 HANDLE_UNICODE_SURROGATE(uv, flags);
760c7c2f 197 }
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198 }
199#endif
200 return d;
201 }
202
203 /* Not 3-byte; that means the code point is at least 0x1_0000 on ASCII
204 * platforms, and 0x4000 on EBCDIC. There are problematic cases that can
205 * happen starting with 4-byte characters on ASCII platforms. We unify the
206 * code for these with EBCDIC, even though some of them require 5-bytes on
207 * those, because khw believes the code saving is worth the very slight
208 * performance hit on these high EBCDIC code points. */
209
210 if (UNLIKELY(UNICODE_IS_SUPER(uv))) {
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211 if (UNLIKELY(uv > MAX_EXTERNALLY_LEGAL_CP)) {
212 Perl_croak(aTHX_ cp_above_legal_max, uv, MAX_EXTERNALLY_LEGAL_CP);
a5bf80e0 213 }
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214 if ( (flags & UNICODE_WARN_SUPER)
215 || ( (flags & UNICODE_WARN_PERL_EXTENDED)
216 && UNICODE_IS_PERL_EXTENDED(uv)))
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217 {
218 Perl_ck_warner_d(aTHX_ packWARN(WARN_NON_UNICODE),
219
220 /* Choose the more dire applicable warning */
d044b7a7 221 (UNICODE_IS_PERL_EXTENDED(uv))
57ff5f59 222 ? perl_extended_cp_format
c94c2f39 223 : super_cp_format,
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224 uv);
225 }
56576a04 226 if ( (flags & UNICODE_DISALLOW_SUPER)
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227 || ( (flags & UNICODE_DISALLOW_PERL_EXTENDED)
228 && UNICODE_IS_PERL_EXTENDED(uv)))
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229 {
230 return NULL;
231 }
232 }
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233 else if (UNLIKELY(UNICODE_IS_END_PLANE_NONCHAR_GIVEN_NOT_SUPER(uv))) {
234 HANDLE_UNICODE_NONCHAR(uv, flags);
507b9800 235 }
d9432125 236
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237 /* Test for and handle 4-byte result. In the test immediately below, the
238 * 8 is for start bytes F0-F7 (which are all the possible ones for 4 byte
239 * characters). The 3 is for 3 continuation bytes; these each contribute
240 * SHIFT bits. This yields 0x4_0000 on EBCDIC platforms, 0x20_0000 on
241 * ASCII, so 4 bytes covers the range 0x4000-0x3_FFFF on EBCDIC;
242 * 0x1_0000-0x1F_FFFF on ASCII */
243 if (uv < (8 * (1U << (3 * SHIFT)))) {
244 *d++ = I8_TO_NATIVE_UTF8(( uv >> ((4 - 1) * SHIFT)) | UTF_START_MARK(4));
245 *d++ = I8_TO_NATIVE_UTF8(((uv >> ((3 - 1) * SHIFT)) & MASK) | MARK);
246 *d++ = I8_TO_NATIVE_UTF8(((uv >> ((2 - 1) * SHIFT)) & MASK) | MARK);
247 *d++ = I8_TO_NATIVE_UTF8(( uv /* (1 - 1) */ & MASK) | MARK);
248
249#ifdef EBCDIC /* These were handled on ASCII platforms in the code for 3-byte
250 characters. The end-plane non-characters for EBCDIC were
251 handled just above */
252 if (UNLIKELY(UNICODE_IS_32_CONTIGUOUS_NONCHARS(uv))) {
253 HANDLE_UNICODE_NONCHAR(uv, flags);
d528804a 254 }
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255 else if (UNLIKELY(UNICODE_IS_SURROGATE(uv))) {
256 HANDLE_UNICODE_SURROGATE(uv, flags);
257 }
258#endif
259
260 return d;
261 }
262
263 /* Not 4-byte; that means the code point is at least 0x20_0000 on ASCII
264 * platforms, and 0x4000 on EBCDIC. At this point we switch to a loop
265 * format. The unrolled version above turns out to not save all that much
266 * time, and at these high code points (well above the legal Unicode range
267 * on ASCII platforms, and well above anything in common use in EBCDIC),
268 * khw believes that less code outweighs slight performance gains. */
269
d9432125 270 {
5aaebcb3 271 STRLEN len = OFFUNISKIP(uv);
1d72bdf6
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272 U8 *p = d+len-1;
273 while (p > d) {
4c8cd605 274 *p-- = I8_TO_NATIVE_UTF8((uv & UTF_CONTINUATION_MASK) | UTF_CONTINUATION_MARK);
1d72bdf6
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275 uv >>= UTF_ACCUMULATION_SHIFT;
276 }
4c8cd605 277 *p = I8_TO_NATIVE_UTF8((uv & UTF_START_MASK(len)) | UTF_START_MARK(len));
1d72bdf6
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278 return d+len;
279 }
a0ed51b3 280}
a5bf80e0 281
646ca15d 282/*
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283=for apidoc uvchr_to_utf8
284
bcb1a2d4 285Adds the UTF-8 representation of the native code point C<uv> to the end
f2fc1b45 286of the string C<d>; C<d> should have at least C<UVCHR_SKIP(uv)+1> (up to
c749c9fd
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287C<UTF8_MAXBYTES+1>) free bytes available. The return value is the pointer to
288the byte after the end of the new character. In other words,
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289
290 d = uvchr_to_utf8(d, uv);
291
292is the recommended wide native character-aware way of saying
293
294 *(d++) = uv;
295
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296This function accepts any code point from 0..C<IV_MAX> as input.
297C<IV_MAX> is typically 0x7FFF_FFFF in a 32-bit word.
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298
299It is possible to forbid or warn on non-Unicode code points, or those that may
300be problematic by using L</uvchr_to_utf8_flags>.
de69f3af 301
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302=cut
303*/
304
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305/* This is also a macro */
306PERL_CALLCONV U8* Perl_uvchr_to_utf8(pTHX_ U8 *d, UV uv);
307
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308U8 *
309Perl_uvchr_to_utf8(pTHX_ U8 *d, UV uv)
310{
de69f3af 311 return uvchr_to_utf8(d, uv);
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312}
313
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314/*
315=for apidoc uvchr_to_utf8_flags
316
317Adds the UTF-8 representation of the native code point C<uv> to the end
f2fc1b45 318of the string C<d>; C<d> should have at least C<UVCHR_SKIP(uv)+1> (up to
c749c9fd
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319C<UTF8_MAXBYTES+1>) free bytes available. The return value is the pointer to
320the byte after the end of the new character. In other words,
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321
322 d = uvchr_to_utf8_flags(d, uv, flags);
323
324or, in most cases,
325
326 d = uvchr_to_utf8_flags(d, uv, 0);
327
328This is the Unicode-aware way of saying
329
330 *(d++) = uv;
331
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332If C<flags> is 0, this function accepts any code point from 0..C<IV_MAX> as
333input. C<IV_MAX> is typically 0x7FFF_FFFF in a 32-bit word.
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334
335Specifying C<flags> can further restrict what is allowed and not warned on, as
336follows:
de69f3af 337
796b6530 338If C<uv> is a Unicode surrogate code point and C<UNICODE_WARN_SURROGATE> is set,
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339the function will raise a warning, provided UTF8 warnings are enabled. If
340instead C<UNICODE_DISALLOW_SURROGATE> is set, the function will fail and return
341NULL. If both flags are set, the function will both warn and return NULL.
de69f3af 342
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343Similarly, the C<UNICODE_WARN_NONCHAR> and C<UNICODE_DISALLOW_NONCHAR> flags
344affect how the function handles a Unicode non-character.
93e6dbd6 345
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346And likewise, the C<UNICODE_WARN_SUPER> and C<UNICODE_DISALLOW_SUPER> flags
347affect the handling of code points that are above the Unicode maximum of
3480x10FFFF. Languages other than Perl may not be able to accept files that
349contain these.
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350
351The flag C<UNICODE_WARN_ILLEGAL_INTERCHANGE> selects all three of
352the above WARN flags; and C<UNICODE_DISALLOW_ILLEGAL_INTERCHANGE> selects all
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353three DISALLOW flags. C<UNICODE_DISALLOW_ILLEGAL_INTERCHANGE> restricts the
354allowed inputs to the strict UTF-8 traditionally defined by Unicode.
355Similarly, C<UNICODE_WARN_ILLEGAL_C9_INTERCHANGE> and
356C<UNICODE_DISALLOW_ILLEGAL_C9_INTERCHANGE> are shortcuts to select the
357above-Unicode and surrogate flags, but not the non-character ones, as
358defined in
359L<Unicode Corrigendum #9|http://www.unicode.org/versions/corrigendum9.html>.
360See L<perlunicode/Noncharacter code points>.
93e6dbd6 361
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362Extremely high code points were never specified in any standard, and require an
363extension to UTF-8 to express, which Perl does. It is likely that programs
364written in something other than Perl would not be able to read files that
365contain these; nor would Perl understand files written by something that uses a
366different extension. For these reasons, there is a separate set of flags that
367can warn and/or disallow these extremely high code points, even if other
368above-Unicode ones are accepted. They are the C<UNICODE_WARN_PERL_EXTENDED>
369and C<UNICODE_DISALLOW_PERL_EXTENDED> flags. For more information see
370L</C<UTF8_GOT_PERL_EXTENDED>>. Of course C<UNICODE_DISALLOW_SUPER> will
371treat all above-Unicode code points, including these, as malformations. (Note
372that the Unicode standard considers anything above 0x10FFFF to be illegal, but
373there are standards predating it that allow up to 0x7FFF_FFFF (2**31 -1))
374
375A somewhat misleadingly named synonym for C<UNICODE_WARN_PERL_EXTENDED> is
376retained for backward compatibility: C<UNICODE_WARN_ABOVE_31_BIT>. Similarly,
377C<UNICODE_DISALLOW_ABOVE_31_BIT> is usable instead of the more accurately named
378C<UNICODE_DISALLOW_PERL_EXTENDED>. The names are misleading because these
379flags can apply to code points that actually do fit in 31 bits. This happens
380on EBCDIC platforms, and sometimes when the L<overlong
381malformation|/C<UTF8_GOT_LONG>> is also present. The new names accurately
382describe the situation in all cases.
de69f3af 383
de69f3af
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384=cut
385*/
386
387/* This is also a macro */
388PERL_CALLCONV U8* Perl_uvchr_to_utf8_flags(pTHX_ U8 *d, UV uv, UV flags);
389
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390U8 *
391Perl_uvchr_to_utf8_flags(pTHX_ U8 *d, UV uv, UV flags)
392{
de69f3af 393 return uvchr_to_utf8_flags(d, uv, flags);
07693fe6
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394}
395
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396#ifndef UV_IS_QUAD
397
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398STATIC int
399S_is_utf8_cp_above_31_bits(const U8 * const s,
400 const U8 * const e,
401 const bool consider_overlongs)
83dc0f42
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402{
403 /* Returns TRUE if the first code point represented by the Perl-extended-
404 * UTF-8-encoded string starting at 's', and looking no further than 'e -
405 * 1' doesn't fit into 31 bytes. That is, that if it is >= 2**31.
406 *
407 * The function handles the case where the input bytes do not include all
408 * the ones necessary to represent a full character. That is, they may be
409 * the intial bytes of the representation of a code point, but possibly
410 * the final ones necessary for the complete representation may be beyond
411 * 'e - 1'.
412 *
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413 * The function also can handle the case where the input is an overlong
414 * sequence. If 'consider_overlongs' is 0, the function assumes the
415 * input is not overlong, without checking, and will return based on that
416 * assumption. If this parameter is 1, the function will go to the trouble
417 * of figuring out if it actually evaluates to above or below 31 bits.
83dc0f42 418 *
e050c007 419 * The sequence is otherwise assumed to be well-formed, without checking.
83dc0f42
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420 */
421
e050c007
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422 const STRLEN len = e - s;
423 int is_overlong;
424
425 PERL_ARGS_ASSERT_IS_UTF8_CP_ABOVE_31_BITS;
426
427 assert(! UTF8_IS_INVARIANT(*s) && e > s);
428
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429#ifdef EBCDIC
430
e050c007 431 PERL_UNUSED_ARG(consider_overlongs);
83dc0f42 432
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433 /* On the EBCDIC code pages we handle, only the native start byte 0xFE can
434 * mean a 32-bit or larger code point (0xFF is an invariant). 0xFE can
435 * also be the start byte for a 31-bit code point; we need at least 2
436 * bytes, and maybe up through 8 bytes, to determine that. (It can also be
437 * the start byte for an overlong sequence, but for 30-bit or smaller code
438 * points, so we don't have to worry about overlongs on EBCDIC.) */
439 if (*s != 0xFE) {
440 return 0;
441 }
83dc0f42 442
e050c007
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443 if (len == 1) {
444 return -1;
445 }
83dc0f42 446
e050c007 447#else
83dc0f42 448
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449 /* On ASCII, FE and FF are the only start bytes that can evaluate to
450 * needing more than 31 bits. */
451 if (LIKELY(*s < 0xFE)) {
452 return 0;
453 }
83dc0f42 454
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455 /* What we have left are FE and FF. Both of these require more than 31
456 * bits unless they are for overlongs. */
457 if (! consider_overlongs) {
458 return 1;
459 }
83dc0f42 460
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461 /* Here, we have FE or FF. If the input isn't overlong, it evaluates to
462 * above 31 bits. But we need more than one byte to discern this, so if
463 * passed just the start byte, it could be an overlong evaluating to
464 * smaller */
465 if (len == 1) {
466 return -1;
467 }
83dc0f42 468
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469 /* Having excluded len==1, and knowing that FE and FF are both valid start
470 * bytes, we can call the function below to see if the sequence is
471 * overlong. (We don't need the full generality of the called function,
472 * but for these huge code points, speed shouldn't be a consideration, and
473 * the compiler does have enough information, since it's static to this
474 * file, to optimize to just the needed parts.) */
475 is_overlong = is_utf8_overlong_given_start_byte_ok(s, len);
83dc0f42 476
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477 /* If it isn't overlong, more than 31 bits are required. */
478 if (is_overlong == 0) {
479 return 1;
480 }
83dc0f42 481
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482 /* If it is indeterminate if it is overlong, return that */
483 if (is_overlong < 0) {
484 return -1;
485 }
486
487 /* Here is overlong. Such a sequence starting with FE is below 31 bits, as
488 * the max it can be is 2**31 - 1 */
489 if (*s == 0xFE) {
490 return 0;
83dc0f42
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491 }
492
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493#endif
494
495 /* Here, ASCII and EBCDIC rejoin:
496 * On ASCII: We have an overlong sequence starting with FF
497 * On EBCDIC: We have a sequence starting with FE. */
498
499 { /* For C89, use a block so the declaration can be close to its use */
500
501#ifdef EBCDIC
502
5f995336
KW
503 /* U+7FFFFFFF (2 ** 31 - 1)
504 * [0] [1] [2] [3] [4] [5] [6] [7] [8] [9] 10 11 12 13
505 * IBM-1047: \xFE\x41\x41\x41\x41\x41\x41\x42\x73\x73\x73\x73\x73\x73
506 * IBM-037: \xFE\x41\x41\x41\x41\x41\x41\x42\x72\x72\x72\x72\x72\x72
507 * POSIX-BC: \xFE\x41\x41\x41\x41\x41\x41\x42\x75\x75\x75\x75\x75\x75
508 * I8: \xFF\xA0\xA0\xA0\xA0\xA0\xA0\xA1\xBF\xBF\xBF\xBF\xBF\xBF
509 * U+80000000 (2 ** 31):
510 * IBM-1047: \xFE\x41\x41\x41\x41\x41\x41\x43\x41\x41\x41\x41\x41\x41
511 * IBM-037: \xFE\x41\x41\x41\x41\x41\x41\x43\x41\x41\x41\x41\x41\x41
512 * POSIX-BC: \xFE\x41\x41\x41\x41\x41\x41\x43\x41\x41\x41\x41\x41\x41
513 * I8: \xFF\xA0\xA0\xA0\xA0\xA0\xA0\xA2\xA0\xA0\xA0\xA0\xA0\xA0
e050c007
KW
514 *
515 * and since we know that *s = \xfe, any continuation sequcence
516 * following it that is gt the below is above 31 bits
517 [0] [1] [2] [3] [4] [5] [6] */
518 const U8 conts_for_highest_30_bit[] = "\x41\x41\x41\x41\x41\x41\x42";
519
520#else
521
522 /* FF overlong for U+7FFFFFFF (2 ** 31 - 1)
523 * ASCII: \xFF\x80\x80\x80\x80\x80\x80\x81\xBF\xBF\xBF\xBF\xBF
524 * FF overlong for U+80000000 (2 ** 31):
525 * ASCII: \xFF\x80\x80\x80\x80\x80\x80\x82\x80\x80\x80\x80\x80
526 * and since we know that *s = \xff, any continuation sequcence
527 * following it that is gt the below is above 30 bits
528 [0] [1] [2] [3] [4] [5] [6] */
529 const U8 conts_for_highest_30_bit[] = "\x80\x80\x80\x80\x80\x80\x81";
5f995336 530
83dc0f42
KW
531
532#endif
e050c007
KW
533 const STRLEN conts_len = sizeof(conts_for_highest_30_bit) - 1;
534 const STRLEN cmp_len = MIN(conts_len, len - 1);
535
536 /* Now compare the continuation bytes in s with the ones we have
537 * compiled in that are for the largest 30 bit code point. If we have
538 * enough bytes available to determine the answer, or the bytes we do
539 * have differ from them, we can compare the two to get a definitive
540 * answer (Note that in UTF-EBCDIC, the two lowest possible
541 * continuation bytes are \x41 and \x42.) */
542 if (cmp_len >= conts_len || memNE(s + 1,
543 conts_for_highest_30_bit,
544 cmp_len))
545 {
546 return cBOOL(memGT(s + 1, conts_for_highest_30_bit, cmp_len));
547 }
83dc0f42 548
e050c007
KW
549 /* Here, all the bytes we have are the same as the highest 30-bit code
550 * point, but we are missing so many bytes that we can't make the
551 * determination */
552 return -1;
553 }
83dc0f42
KW
554}
555
57ff5f59
KW
556#endif
557
d6be65ae 558PERL_STATIC_INLINE int
12a4bed3
KW
559S_is_utf8_overlong_given_start_byte_ok(const U8 * const s, const STRLEN len)
560{
d6be65ae
KW
561 /* Returns an int indicating whether or not the UTF-8 sequence from 's' to
562 * 's' + 'len' - 1 is an overlong. It returns 1 if it is an overlong; 0 if
563 * it isn't, and -1 if there isn't enough information to tell. This last
564 * return value can happen if the sequence is incomplete, missing some
565 * trailing bytes that would form a complete character. If there are
566 * enough bytes to make a definitive decision, this function does so.
567 * Usually 2 bytes sufficient.
568 *
569 * Overlongs can occur whenever the number of continuation bytes changes.
570 * That means whenever the number of leading 1 bits in a start byte
571 * increases from the next lower start byte. That happens for start bytes
572 * C0, E0, F0, F8, FC, FE, and FF. On modern perls, the following illegal
573 * start bytes have already been excluded, so don't need to be tested here;
12a4bed3
KW
574 * ASCII platforms: C0, C1
575 * EBCDIC platforms C0, C1, C2, C3, C4, E0
d6be65ae 576 */
12a4bed3
KW
577
578 const U8 s0 = NATIVE_UTF8_TO_I8(s[0]);
579 const U8 s1 = NATIVE_UTF8_TO_I8(s[1]);
580
581 PERL_ARGS_ASSERT_IS_UTF8_OVERLONG_GIVEN_START_BYTE_OK;
582 assert(len > 1 && UTF8_IS_START(*s));
583
584 /* Each platform has overlongs after the start bytes given above (expressed
585 * in I8 for EBCDIC). What constitutes an overlong varies by platform, but
586 * the logic is the same, except the E0 overlong has already been excluded
587 * on EBCDIC platforms. The values below were found by manually
588 * inspecting the UTF-8 patterns. See the tables in utf8.h and
589 * utfebcdic.h. */
590
591# ifdef EBCDIC
592# define F0_ABOVE_OVERLONG 0xB0
593# define F8_ABOVE_OVERLONG 0xA8
594# define FC_ABOVE_OVERLONG 0xA4
595# define FE_ABOVE_OVERLONG 0xA2
596# define FF_OVERLONG_PREFIX "\xfe\x41\x41\x41\x41\x41\x41\x41"
597 /* I8(0xfe) is FF */
598# else
599
600 if (s0 == 0xE0 && UNLIKELY(s1 < 0xA0)) {
d6be65ae 601 return 1;
12a4bed3
KW
602 }
603
604# define F0_ABOVE_OVERLONG 0x90
605# define F8_ABOVE_OVERLONG 0x88
606# define FC_ABOVE_OVERLONG 0x84
607# define FE_ABOVE_OVERLONG 0x82
608# define FF_OVERLONG_PREFIX "\xff\x80\x80\x80\x80\x80\x80"
609# endif
610
611
612 if ( (s0 == 0xF0 && UNLIKELY(s1 < F0_ABOVE_OVERLONG))
613 || (s0 == 0xF8 && UNLIKELY(s1 < F8_ABOVE_OVERLONG))
614 || (s0 == 0xFC && UNLIKELY(s1 < FC_ABOVE_OVERLONG))
615 || (s0 == 0xFE && UNLIKELY(s1 < FE_ABOVE_OVERLONG)))
616 {
d6be65ae 617 return 1;
12a4bed3
KW
618 }
619
b0b342d4 620 /* Check for the FF overlong */
d6be65ae 621 return isFF_OVERLONG(s, len);
b0b342d4
KW
622}
623
8d6204cc 624PERL_STATIC_INLINE int
b0b342d4
KW
625S_isFF_OVERLONG(const U8 * const s, const STRLEN len)
626{
8d6204cc
KW
627 /* Returns an int indicating whether or not the UTF-8 sequence from 's' to
628 * 'e' - 1 is an overlong beginning with \xFF. It returns 1 if it is; 0 if
629 * it isn't, and -1 if there isn't enough information to tell. This last
630 * return value can happen if the sequence is incomplete, missing some
631 * trailing bytes that would form a complete character. If there are
632 * enough bytes to make a definitive decision, this function does so. */
633
b0b342d4 634 PERL_ARGS_ASSERT_ISFF_OVERLONG;
12a4bed3 635
8d6204cc
KW
636 /* To be an FF overlong, all the available bytes must match */
637 if (LIKELY(memNE(s, FF_OVERLONG_PREFIX,
638 MIN(len, sizeof(FF_OVERLONG_PREFIX) - 1))))
639 {
640 return 0;
641 }
642
643 /* To be an FF overlong sequence, all the bytes in FF_OVERLONG_PREFIX must
644 * be there; what comes after them doesn't matter. See tables in utf8.h,
b0b342d4 645 * utfebcdic.h. */
8d6204cc
KW
646 if (len >= sizeof(FF_OVERLONG_PREFIX) - 1) {
647 return 1;
648 }
12a4bed3 649
8d6204cc
KW
650 /* The missing bytes could cause the result to go one way or the other, so
651 * the result is indeterminate */
652 return -1;
12a4bed3
KW
653}
654
d22ec717 655#if defined(UV_IS_QUAD) /* These assume IV_MAX is 2**63-1 */
a77c906e
KW
656# ifdef EBCDIC /* Actually is I8 */
657# define HIGHEST_REPRESENTABLE_UTF8 \
d22ec717 658 "\xFF\xA7\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF"
a77c906e
KW
659# else
660# define HIGHEST_REPRESENTABLE_UTF8 \
d22ec717 661 "\xFF\x80\x87\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF"
a77c906e
KW
662# endif
663#endif
664
c285bbc4 665PERL_STATIC_INLINE int
e050c007
KW
666S_does_utf8_overflow(const U8 * const s,
667 const U8 * e,
668 const bool consider_overlongs)
a77c906e 669{
c285bbc4 670 /* Returns an int indicating whether or not the UTF-8 sequence from 's' to
d22ec717
KW
671 * 'e' - 1 would overflow an IV on this platform; that is if it represents
672 * a code point larger than the highest representable code point. It
673 * returns 1 if it does overflow; 0 if it doesn't, and -1 if there isn't
674 * enough information to tell. This last return value can happen if the
675 * sequence is incomplete, missing some trailing bytes that would form a
676 * complete character. If there are enough bytes to make a definitive
677 * decision, this function does so.
c285bbc4 678 *
e050c007
KW
679 * If 'consider_overlongs' is TRUE, the function checks for the possibility
680 * that the sequence is an overlong that doesn't overflow. Otherwise, it
681 * assumes the sequence is not an overlong. This can give different
682 * results only on ASCII 32-bit platforms.
683 *
c285bbc4
KW
684 * (For ASCII platforms, we could use memcmp() because we don't have to
685 * convert each byte to I8, but it's very rare input indeed that would
686 * approach overflow, so the loop below will likely only get executed once.)
687 *
688 * 'e' - 1 must not be beyond a full character. */
a77c906e 689
a77c906e
KW
690
691 PERL_ARGS_ASSERT_DOES_UTF8_OVERFLOW;
692 assert(s <= e && s + UTF8SKIP(s) >= e);
693
d22ec717
KW
694#if ! defined(UV_IS_QUAD)
695
696 return is_utf8_cp_above_31_bits(s, e, consider_overlongs);
697
698#else
699
700 PERL_UNUSED_ARG(consider_overlongs);
701
702 {
703 const STRLEN len = e - s;
704 const U8 *x;
705 const U8 * y = (const U8 *) HIGHEST_REPRESENTABLE_UTF8;
706
707 for (x = s; x < e; x++, y++) {
708
709 if (UNLIKELY(NATIVE_UTF8_TO_I8(*x) == *y)) {
710 continue;
711 }
712
713 /* If this byte is larger than the corresponding highest UTF-8
714 * byte, the sequence overflow; otherwise the byte is less than,
715 * and so the sequence doesn't overflow */
716 return NATIVE_UTF8_TO_I8(*x) > *y;
717
718 }
719
720 /* Got to the end and all bytes are the same. If the input is a whole
721 * character, it doesn't overflow. And if it is a partial character,
722 * there's not enough information to tell */
723 if (len < sizeof(HIGHEST_REPRESENTABLE_UTF8) - 1) {
724 return -1;
725 }
726
727 return 0;
728 }
729
730#endif
731
732}
733
734#if 0
735
736/* This is the portions of the above function that deal with UV_MAX instead of
737 * IV_MAX. They are left here in case we want to combine them so that internal
738 * uses can have larger code points. The only logic difference is that the
739 * 32-bit EBCDIC platform is treate like the 64-bit, and the 32-bit ASCII has
740 * different logic.
741 */
742
743/* Anything larger than this will overflow the word if it were converted into a UV */
744#if defined(UV_IS_QUAD)
745# ifdef EBCDIC /* Actually is I8 */
746# define HIGHEST_REPRESENTABLE_UTF8 \
747 "\xFF\xAF\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF"
748# else
749# define HIGHEST_REPRESENTABLE_UTF8 \
750 "\xFF\x80\x8F\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF\xBF"
751# endif
752#else /* 32-bit */
753# ifdef EBCDIC
754# define HIGHEST_REPRESENTABLE_UTF8 \
755 "\xFF\xA0\xA0\xA0\xA0\xA0\xA0\xA3\xBF\xBF\xBF\xBF\xBF\xBF"
756# else
757# define HIGHEST_REPRESENTABLE_UTF8 "\xFE\x83\xBF\xBF\xBF\xBF\xBF"
758# endif
759#endif
760
a77c906e
KW
761#if ! defined(UV_IS_QUAD) && ! defined(EBCDIC)
762
763 /* On 32 bit ASCII machines, many overlongs that start with FF don't
764 * overflow */
e050c007 765 if (consider_overlongs && isFF_OVERLONG(s, len) > 0) {
c285bbc4
KW
766
767 /* To be such an overlong, the first bytes of 's' must match
768 * FF_OVERLONG_PREFIX, which is "\xff\x80\x80\x80\x80\x80\x80". If we
769 * don't have any additional bytes available, the sequence, when
770 * completed might or might not fit in 32 bits. But if we have that
771 * next byte, we can tell for sure. If it is <= 0x83, then it does
772 * fit. */
773 if (len <= sizeof(FF_OVERLONG_PREFIX) - 1) {
774 return -1;
775 }
776
777 return s[sizeof(FF_OVERLONG_PREFIX) - 1] > 0x83;
a77c906e
KW
778 }
779
d22ec717
KW
780/* Starting with the #else, the rest of the function is identical except
781 * 1. we need to move the 'len' declaration to be global to the function
782 * 2. the endif move to just after the UNUSED_ARG.
783 * An empty endif is given just below to satisfy the preprocessor
784 */
a77c906e
KW
785#endif
786
d22ec717 787#endif
a77c906e 788
12a4bed3
KW
789#undef F0_ABOVE_OVERLONG
790#undef F8_ABOVE_OVERLONG
791#undef FC_ABOVE_OVERLONG
792#undef FE_ABOVE_OVERLONG
793#undef FF_OVERLONG_PREFIX
794
35f8c9bd 795STRLEN
edc2c47a 796Perl__is_utf8_char_helper(const U8 * const s, const U8 * e, const U32 flags)
35f8c9bd 797{
2b479609 798 STRLEN len;
12a4bed3 799 const U8 *x;
35f8c9bd 800
2b479609
KW
801 /* A helper function that should not be called directly.
802 *
803 * This function returns non-zero if the string beginning at 's' and
804 * looking no further than 'e - 1' is well-formed Perl-extended-UTF-8 for a
805 * code point; otherwise it returns 0. The examination stops after the
806 * first code point in 's' is validated, not looking at the rest of the
807 * input. If 'e' is such that there are not enough bytes to represent a
808 * complete code point, this function will return non-zero anyway, if the
809 * bytes it does have are well-formed UTF-8 as far as they go, and aren't
810 * excluded by 'flags'.
811 *
812 * A non-zero return gives the number of bytes required to represent the
813 * code point. Be aware that if the input is for a partial character, the
814 * return will be larger than 'e - s'.
815 *
816 * This function assumes that the code point represented is UTF-8 variant.
56576a04
KW
817 * The caller should have excluded the possibility of it being invariant
818 * before calling this function.
2b479609
KW
819 *
820 * 'flags' can be 0, or any combination of the UTF8_DISALLOW_foo flags
821 * accepted by L</utf8n_to_uvchr>. If non-zero, this function will return
822 * 0 if the code point represented is well-formed Perl-extended-UTF-8, but
823 * disallowed by the flags. If the input is only for a partial character,
824 * the function will return non-zero if there is any sequence of
825 * well-formed UTF-8 that, when appended to the input sequence, could
826 * result in an allowed code point; otherwise it returns 0. Non characters
827 * cannot be determined based on partial character input. But many of the
828 * other excluded types can be determined with just the first one or two
829 * bytes.
830 *
831 */
832
833 PERL_ARGS_ASSERT__IS_UTF8_CHAR_HELPER;
834
835 assert(0 == (flags & ~(UTF8_DISALLOW_ILLEGAL_INTERCHANGE
d044b7a7 836 |UTF8_DISALLOW_PERL_EXTENDED)));
2b479609 837 assert(! UTF8_IS_INVARIANT(*s));
35f8c9bd 838
2b479609 839 /* A variant char must begin with a start byte */
35f8c9bd
KW
840 if (UNLIKELY(! UTF8_IS_START(*s))) {
841 return 0;
842 }
843
edc2c47a
KW
844 /* Examine a maximum of a single whole code point */
845 if (e - s > UTF8SKIP(s)) {
846 e = s + UTF8SKIP(s);
847 }
848
2b479609
KW
849 len = e - s;
850
851 if (flags && isUTF8_POSSIBLY_PROBLEMATIC(*s)) {
852 const U8 s0 = NATIVE_UTF8_TO_I8(s[0]);
35f8c9bd 853
56576a04
KW
854 /* Here, we are disallowing some set of largish code points, and the
855 * first byte indicates the sequence is for a code point that could be
856 * in the excluded set. We generally don't have to look beyond this or
857 * the second byte to see if the sequence is actually for one of the
858 * excluded classes. The code below is derived from this table:
859 *
2b479609
KW
860 * UTF-8 UTF-EBCDIC I8
861 * U+D800: \xED\xA0\x80 \xF1\xB6\xA0\xA0 First surrogate
862 * U+DFFF: \xED\xBF\xBF \xF1\xB7\xBF\xBF Final surrogate
863 * U+110000: \xF4\x90\x80\x80 \xF9\xA2\xA0\xA0\xA0 First above Unicode
864 *
56576a04
KW
865 * Keep in mind that legal continuation bytes range between \x80..\xBF
866 * for UTF-8, and \xA0..\xBF for I8. Anything above those aren't
867 * continuation bytes. Hence, we don't have to test the upper edge
868 * because if any of those is encountered, the sequence is malformed,
869 * and would fail elsewhere in this function.
870 *
871 * The code here likewise assumes that there aren't other
872 * malformations; again the function should fail elsewhere because of
873 * these. For example, an overlong beginning with FC doesn't actually
874 * have to be a super; it could actually represent a small code point,
875 * even U+0000. But, since overlongs (and other malformations) are
876 * illegal, the function should return FALSE in either case.
2b479609
KW
877 */
878
879#ifdef EBCDIC /* On EBCDIC, these are actually I8 bytes */
880# define FIRST_START_BYTE_THAT_IS_DEFINITELY_SUPER 0xFA
19794540 881# define IS_UTF8_2_BYTE_SUPER(s0, s1) ((s0) == 0xF9 && (s1) >= 0xA2)
2b479609 882
19794540
KW
883# define IS_UTF8_2_BYTE_SURROGATE(s0, s1) ((s0) == 0xF1 \
884 /* B6 and B7 */ \
885 && ((s1) & 0xFE ) == 0xB6)
57ff5f59 886# define isUTF8_PERL_EXTENDED(s) (*s == I8_TO_NATIVE_UTF8(0xFF))
2b479609
KW
887#else
888# define FIRST_START_BYTE_THAT_IS_DEFINITELY_SUPER 0xF5
19794540
KW
889# define IS_UTF8_2_BYTE_SUPER(s0, s1) ((s0) == 0xF4 && (s1) >= 0x90)
890# define IS_UTF8_2_BYTE_SURROGATE(s0, s1) ((s0) == 0xED && (s1) >= 0xA0)
57ff5f59 891# define isUTF8_PERL_EXTENDED(s) (*s >= 0xFE)
2b479609
KW
892#endif
893
894 if ( (flags & UTF8_DISALLOW_SUPER)
ddb65933
KW
895 && UNLIKELY(s0 >= FIRST_START_BYTE_THAT_IS_DEFINITELY_SUPER))
896 {
2b479609
KW
897 return 0; /* Above Unicode */
898 }
899
d044b7a7 900 if ( (flags & UTF8_DISALLOW_PERL_EXTENDED)
57ff5f59 901 && UNLIKELY(isUTF8_PERL_EXTENDED(s)))
2b479609 902 {
57ff5f59 903 return 0;
2b479609
KW
904 }
905
906 if (len > 1) {
907 const U8 s1 = NATIVE_UTF8_TO_I8(s[1]);
908
909 if ( (flags & UTF8_DISALLOW_SUPER)
19794540 910 && UNLIKELY(IS_UTF8_2_BYTE_SUPER(s0, s1)))
2b479609
KW
911 {
912 return 0; /* Above Unicode */
913 }
914
915 if ( (flags & UTF8_DISALLOW_SURROGATE)
19794540 916 && UNLIKELY(IS_UTF8_2_BYTE_SURROGATE(s0, s1)))
2b479609
KW
917 {
918 return 0; /* Surrogate */
919 }
920
921 if ( (flags & UTF8_DISALLOW_NONCHAR)
922 && UNLIKELY(UTF8_IS_NONCHAR(s, e)))
923 {
924 return 0; /* Noncharacter code point */
925 }
926 }
927 }
928
929 /* Make sure that all that follows are continuation bytes */
35f8c9bd
KW
930 for (x = s + 1; x < e; x++) {
931 if (UNLIKELY(! UTF8_IS_CONTINUATION(*x))) {
932 return 0;
933 }
934 }
935
af13dd8a 936 /* Here is syntactically valid. Next, make sure this isn't the start of an
12a4bed3 937 * overlong. */
d6be65ae 938 if (len > 1 && is_utf8_overlong_given_start_byte_ok(s, len) > 0) {
12a4bed3 939 return 0;
af13dd8a
KW
940 }
941
12a4bed3
KW
942 /* And finally, that the code point represented fits in a word on this
943 * platform */
e050c007
KW
944 if (0 < does_utf8_overflow(s, e,
945 0 /* Don't consider overlongs */
946 ))
947 {
12a4bed3 948 return 0;
35f8c9bd
KW
949 }
950
2b479609 951 return UTF8SKIP(s);
35f8c9bd
KW
952}
953
7e2f38b2 954char *
63ab03b3 955Perl__byte_dump_string(pTHX_ const U8 * const start, const STRLEN len, const bool format)
7cf8d05d
KW
956{
957 /* Returns a mortalized C string that is a displayable copy of the 'len'
63ab03b3 958 * bytes starting at 'start'. 'format' gives how to display each byte.
7e2f38b2
KW
959 * Currently, there are only two formats, so it is currently a bool:
960 * 0 \xab
961 * 1 ab (that is a space between two hex digit bytes)
962 */
7cf8d05d
KW
963
964 const STRLEN output_len = 4 * len + 1; /* 4 bytes per each input, plus a
965 trailing NUL */
63ab03b3
KW
966 const U8 * s = start;
967 const U8 * const e = start + len;
7cf8d05d
KW
968 char * output;
969 char * d;
970
971 PERL_ARGS_ASSERT__BYTE_DUMP_STRING;
972
973 Newx(output, output_len, char);
974 SAVEFREEPV(output);
975
976 d = output;
63ab03b3 977 for (s = start; s < e; s++) {
7cf8d05d
KW
978 const unsigned high_nibble = (*s & 0xF0) >> 4;
979 const unsigned low_nibble = (*s & 0x0F);
980
7e2f38b2 981 if (format) {
63ab03b3
KW
982 if (s > start) {
983 *d++ = ' ';
984 }
7e2f38b2
KW
985 }
986 else {
987 *d++ = '\\';
988 *d++ = 'x';
989 }
7cf8d05d
KW
990
991 if (high_nibble < 10) {
992 *d++ = high_nibble + '0';
993 }
994 else {
995 *d++ = high_nibble - 10 + 'a';
996 }
997
998 if (low_nibble < 10) {
999 *d++ = low_nibble + '0';
1000 }
1001 else {
1002 *d++ = low_nibble - 10 + 'a';
1003 }
1004 }
1005
1006 *d = '\0';
1007 return output;
1008}
1009
806547a7 1010PERL_STATIC_INLINE char *
7cf8d05d
KW
1011S_unexpected_non_continuation_text(pTHX_ const U8 * const s,
1012
1013 /* How many bytes to print */
3cc6a05e 1014 STRLEN print_len,
7cf8d05d
KW
1015
1016 /* Which one is the non-continuation */
1017 const STRLEN non_cont_byte_pos,
1018
1019 /* How many bytes should there be? */
1020 const STRLEN expect_len)
806547a7
KW
1021{
1022 /* Return the malformation warning text for an unexpected continuation
1023 * byte. */
1024
7cf8d05d 1025 const char * const where = (non_cont_byte_pos == 1)
806547a7 1026 ? "immediately"
7cf8d05d
KW
1027 : Perl_form(aTHX_ "%d bytes",
1028 (int) non_cont_byte_pos);
806547a7
KW
1029
1030 PERL_ARGS_ASSERT_UNEXPECTED_NON_CONTINUATION_TEXT;
1031
7cf8d05d
KW
1032 /* We don't need to pass this parameter, but since it has already been
1033 * calculated, it's likely faster to pass it; verify under DEBUGGING */
1034 assert(expect_len == UTF8SKIP(s));
1035
1036 return Perl_form(aTHX_ "%s: %s (unexpected non-continuation byte 0x%02x,"
1037 " %s after start byte 0x%02x; need %d bytes, got %d)",
1038 malformed_text,
7e2f38b2 1039 _byte_dump_string(s, print_len, 0),
7cf8d05d
KW
1040 *(s + non_cont_byte_pos),
1041 where,
1042 *s,
1043 (int) expect_len,
1044 (int) non_cont_byte_pos);
806547a7
KW
1045}
1046
35f8c9bd
KW
1047/*
1048
de69f3af 1049=for apidoc utf8n_to_uvchr
378516de
KW
1050
1051THIS FUNCTION SHOULD BE USED IN ONLY VERY SPECIALIZED CIRCUMSTANCES.
de69f3af 1052Most code should use L</utf8_to_uvchr_buf>() rather than call this directly.
67e989fb 1053
9041c2e3 1054Bottom level UTF-8 decode routine.
de69f3af 1055Returns the native code point value of the first character in the string C<s>,
746afd53
KW
1056which is assumed to be in UTF-8 (or UTF-EBCDIC) encoding, and no longer than
1057C<curlen> bytes; C<*retlen> (if C<retlen> isn't NULL) will be set to
1058the length, in bytes, of that character.
949cf498
KW
1059
1060The value of C<flags> determines the behavior when C<s> does not point to a
2b5e7bc2
KW
1061well-formed UTF-8 character. If C<flags> is 0, encountering a malformation
1062causes zero to be returned and C<*retlen> is set so that (S<C<s> + C<*retlen>>)
1063is the next possible position in C<s> that could begin a non-malformed
1064character. Also, if UTF-8 warnings haven't been lexically disabled, a warning
1065is raised. Some UTF-8 input sequences may contain multiple malformations.
1066This function tries to find every possible one in each call, so multiple
56576a04 1067warnings can be raised for the same sequence.
949cf498
KW
1068
1069Various ALLOW flags can be set in C<flags> to allow (and not warn on)
1070individual types of malformations, such as the sequence being overlong (that
1071is, when there is a shorter sequence that can express the same code point;
1072overlong sequences are expressly forbidden in the UTF-8 standard due to
1073potential security issues). Another malformation example is the first byte of
1074a character not being a legal first byte. See F<utf8.h> for the list of such
94953955
KW
1075flags. Even if allowed, this function generally returns the Unicode
1076REPLACEMENT CHARACTER when it encounters a malformation. There are flags in
1077F<utf8.h> to override this behavior for the overlong malformations, but don't
1078do that except for very specialized purposes.
949cf498 1079
796b6530 1080The C<UTF8_CHECK_ONLY> flag overrides the behavior when a non-allowed (by other
949cf498
KW
1081flags) malformation is found. If this flag is set, the routine assumes that
1082the caller will raise a warning, and this function will silently just set
d088425d
KW
1083C<retlen> to C<-1> (cast to C<STRLEN>) and return zero.
1084
75200dff 1085Note that this API requires disambiguation between successful decoding a C<NUL>
796b6530 1086character, and an error return (unless the C<UTF8_CHECK_ONLY> flag is set), as
111fa700
KW
1087in both cases, 0 is returned, and, depending on the malformation, C<retlen> may
1088be set to 1. To disambiguate, upon a zero return, see if the first byte of
1089C<s> is 0 as well. If so, the input was a C<NUL>; if not, the input had an
f9380377 1090error. Or you can use C<L</utf8n_to_uvchr_error>>.
949cf498
KW
1091
1092Certain code points are considered problematic. These are Unicode surrogates,
746afd53 1093Unicode non-characters, and code points above the Unicode maximum of 0x10FFFF.
949cf498 1094By default these are considered regular code points, but certain situations
ecc1615f
KW
1095warrant special handling for them, which can be specified using the C<flags>
1096parameter. If C<flags> contains C<UTF8_DISALLOW_ILLEGAL_INTERCHANGE>, all
1097three classes are treated as malformations and handled as such. The flags
1098C<UTF8_DISALLOW_SURROGATE>, C<UTF8_DISALLOW_NONCHAR>, and
1099C<UTF8_DISALLOW_SUPER> (meaning above the legal Unicode maximum) can be set to
1100disallow these categories individually. C<UTF8_DISALLOW_ILLEGAL_INTERCHANGE>
1101restricts the allowed inputs to the strict UTF-8 traditionally defined by
1102Unicode. Use C<UTF8_DISALLOW_ILLEGAL_C9_INTERCHANGE> to use the strictness
1103definition given by
1104L<Unicode Corrigendum #9|http://www.unicode.org/versions/corrigendum9.html>.
1105The difference between traditional strictness and C9 strictness is that the
1106latter does not forbid non-character code points. (They are still discouraged,
1107however.) For more discussion see L<perlunicode/Noncharacter code points>.
1108
1109The flags C<UTF8_WARN_ILLEGAL_INTERCHANGE>,
1110C<UTF8_WARN_ILLEGAL_C9_INTERCHANGE>, C<UTF8_WARN_SURROGATE>,
796b6530
KW
1111C<UTF8_WARN_NONCHAR>, and C<UTF8_WARN_SUPER> will cause warning messages to be
1112raised for their respective categories, but otherwise the code points are
1113considered valid (not malformations). To get a category to both be treated as
1114a malformation and raise a warning, specify both the WARN and DISALLOW flags.
949cf498 1115(But note that warnings are not raised if lexically disabled nor if
796b6530 1116C<UTF8_CHECK_ONLY> is also specified.)
949cf498 1117
57ff5f59
KW
1118Extremely high code points were never specified in any standard, and require an
1119extension to UTF-8 to express, which Perl does. It is likely that programs
1120written in something other than Perl would not be able to read files that
1121contain these; nor would Perl understand files written by something that uses a
1122different extension. For these reasons, there is a separate set of flags that
1123can warn and/or disallow these extremely high code points, even if other
1124above-Unicode ones are accepted. They are the C<UTF8_WARN_PERL_EXTENDED> and
1125C<UTF8_DISALLOW_PERL_EXTENDED> flags. For more information see
1126L</C<UTF8_GOT_PERL_EXTENDED>>. Of course C<UTF8_DISALLOW_SUPER> will treat all
1127above-Unicode code points, including these, as malformations.
1128(Note that the Unicode standard considers anything above 0x10FFFF to be
1129illegal, but there are standards predating it that allow up to 0x7FFF_FFFF
1130(2**31 -1))
1131
1132A somewhat misleadingly named synonym for C<UTF8_WARN_PERL_EXTENDED> is
1133retained for backward compatibility: C<UTF8_WARN_ABOVE_31_BIT>. Similarly,
1134C<UTF8_DISALLOW_ABOVE_31_BIT> is usable instead of the more accurately named
1135C<UTF8_DISALLOW_PERL_EXTENDED>. The names are misleading because these flags
1136can apply to code points that actually do fit in 31 bits. This happens on
1137EBCDIC platforms, and sometimes when the L<overlong
1138malformation|/C<UTF8_GOT_LONG>> is also present. The new names accurately
1139describe the situation in all cases.
1140
ab8e6d41 1141
949cf498
KW
1142All other code points corresponding to Unicode characters, including private
1143use and those yet to be assigned, are never considered malformed and never
1144warn.
67e989fb 1145
37607a96 1146=cut
f9380377
KW
1147
1148Also implemented as a macro in utf8.h
1149*/
1150
1151UV
1152Perl_utf8n_to_uvchr(pTHX_ const U8 *s,
1153 STRLEN curlen,
1154 STRLEN *retlen,
1155 const U32 flags)
1156{
1157 PERL_ARGS_ASSERT_UTF8N_TO_UVCHR;
1158
1159 return utf8n_to_uvchr_error(s, curlen, retlen, flags, NULL);
1160}
1161
1162/*
1163
1164=for apidoc utf8n_to_uvchr_error
1165
1166THIS FUNCTION SHOULD BE USED IN ONLY VERY SPECIALIZED CIRCUMSTANCES.
1167Most code should use L</utf8_to_uvchr_buf>() rather than call this directly.
1168
1169This function is for code that needs to know what the precise malformation(s)
1170are when an error is found.
1171
1172It is like C<L</utf8n_to_uvchr>> but it takes an extra parameter placed after
1173all the others, C<errors>. If this parameter is 0, this function behaves
1174identically to C<L</utf8n_to_uvchr>>. Otherwise, C<errors> should be a pointer
1175to a C<U32> variable, which this function sets to indicate any errors found.
1176Upon return, if C<*errors> is 0, there were no errors found. Otherwise,
1177C<*errors> is the bit-wise C<OR> of the bits described in the list below. Some
1178of these bits will be set if a malformation is found, even if the input
7a65503b 1179C<flags> parameter indicates that the given malformation is allowed; those
f9380377
KW
1180exceptions are noted:
1181
1182=over 4
1183
57ff5f59 1184=item C<UTF8_GOT_PERL_EXTENDED>
f9380377 1185
57ff5f59
KW
1186The input sequence is not standard UTF-8, but a Perl extension. This bit is
1187set only if the input C<flags> parameter contains either the
1188C<UTF8_DISALLOW_PERL_EXTENDED> or the C<UTF8_WARN_PERL_EXTENDED> flags.
1189
1190Code points above 0x7FFF_FFFF (2**31 - 1) were never specified in any standard,
1191and so some extension must be used to express them. Perl uses a natural
1192extension to UTF-8 to represent the ones up to 2**36-1, and invented a further
1193extension to represent even higher ones, so that any code point that fits in a
119464-bit word can be represented. Text using these extensions is not likely to
1195be portable to non-Perl code. We lump both of these extensions together and
1196refer to them as Perl extended UTF-8. There exist other extensions that people
1197have invented, incompatible with Perl's.
1198
1199On EBCDIC platforms starting in Perl v5.24, the Perl extension for representing
1200extremely high code points kicks in at 0x3FFF_FFFF (2**30 -1), which is lower
1201than on ASCII. Prior to that, code points 2**31 and higher were simply
1202unrepresentable, and a different, incompatible method was used to represent
1203code points between 2**30 and 2**31 - 1.
1204
1205On both platforms, ASCII and EBCDIC, C<UTF8_GOT_PERL_EXTENDED> is set if
1206Perl extended UTF-8 is used.
1207
1208In earlier Perls, this bit was named C<UTF8_GOT_ABOVE_31_BIT>, which you still
1209may use for backward compatibility. That name is misleading, as this flag may
1210be set when the code point actually does fit in 31 bits. This happens on
1211EBCDIC platforms, and sometimes when the L<overlong
1212malformation|/C<UTF8_GOT_LONG>> is also present. The new name accurately
1213describes the situation in all cases.
f9380377
KW
1214
1215=item C<UTF8_GOT_CONTINUATION>
1216
1217The input sequence was malformed in that the first byte was a a UTF-8
1218continuation byte.
1219
1220=item C<UTF8_GOT_EMPTY>
1221
1222The input C<curlen> parameter was 0.
1223
1224=item C<UTF8_GOT_LONG>
1225
1226The input sequence was malformed in that there is some other sequence that
1227evaluates to the same code point, but that sequence is shorter than this one.
1228
fecaf136
KW
1229Until Unicode 3.1, it was legal for programs to accept this malformation, but
1230it was discovered that this created security issues.
1231
f9380377
KW
1232=item C<UTF8_GOT_NONCHAR>
1233
1234The code point represented by the input UTF-8 sequence is for a Unicode
1235non-character code point.
1236This bit is set only if the input C<flags> parameter contains either the
1237C<UTF8_DISALLOW_NONCHAR> or the C<UTF8_WARN_NONCHAR> flags.
1238
1239=item C<UTF8_GOT_NON_CONTINUATION>
1240
1241The input sequence was malformed in that a non-continuation type byte was found
1242in a position where only a continuation type one should be.
1243
1244=item C<UTF8_GOT_OVERFLOW>
1245
1246The input sequence was malformed in that it is for a code point that is not
d22ec717 1247representable in the number of bits available in an IV on the current platform.
f9380377
KW
1248
1249=item C<UTF8_GOT_SHORT>
1250
1251The input sequence was malformed in that C<curlen> is smaller than required for
1252a complete sequence. In other words, the input is for a partial character
1253sequence.
1254
1255=item C<UTF8_GOT_SUPER>
1256
1257The input sequence was malformed in that it is for a non-Unicode code point;
1258that is, one above the legal Unicode maximum.
1259This bit is set only if the input C<flags> parameter contains either the
1260C<UTF8_DISALLOW_SUPER> or the C<UTF8_WARN_SUPER> flags.
1261
1262=item C<UTF8_GOT_SURROGATE>
1263
1264The input sequence was malformed in that it is for a -Unicode UTF-16 surrogate
1265code point.
1266This bit is set only if the input C<flags> parameter contains either the
1267C<UTF8_DISALLOW_SURROGATE> or the C<UTF8_WARN_SURROGATE> flags.
1268
1269=back
1270
133551d8
KW
1271To do your own error handling, call this function with the C<UTF8_CHECK_ONLY>
1272flag to suppress any warnings, and then examine the C<*errors> return.
1273
f9380377 1274=cut
37607a96 1275*/
67e989fb 1276
a0ed51b3 1277UV
f9380377
KW
1278Perl_utf8n_to_uvchr_error(pTHX_ const U8 *s,
1279 STRLEN curlen,
1280 STRLEN *retlen,
1281 const U32 flags,
1282 U32 * errors)
a0ed51b3 1283{
d4c19fe8 1284 const U8 * const s0 = s;
2b5e7bc2
KW
1285 U8 * send = NULL; /* (initialized to silence compilers' wrong
1286 warning) */
1287 U32 possible_problems = 0; /* A bit is set here for each potential problem
1288 found as we go along */
eb83ed87 1289 UV uv = *s;
2b5e7bc2
KW
1290 STRLEN expectlen = 0; /* How long should this sequence be?
1291 (initialized to silence compilers' wrong
1292 warning) */
e308b348 1293 STRLEN avail_len = 0; /* When input is too short, gives what that is */
f9380377
KW
1294 U32 discard_errors = 0; /* Used to save branches when 'errors' is NULL;
1295 this gets set and discarded */
a0dbb045 1296
2b5e7bc2
KW
1297 /* The below are used only if there is both an overlong malformation and a
1298 * too short one. Otherwise the first two are set to 's0' and 'send', and
1299 * the third not used at all */
1300 U8 * adjusted_s0 = (U8 *) s0;
e9f2c446
KW
1301 U8 temp_char_buf[UTF8_MAXBYTES + 1]; /* Used to avoid a Newx in this
1302 routine; see [perl #130921] */
2b5e7bc2 1303 UV uv_so_far = 0; /* (Initialized to silence compilers' wrong warning) */
7918f24d 1304
f9380377
KW
1305 PERL_ARGS_ASSERT_UTF8N_TO_UVCHR_ERROR;
1306
1307 if (errors) {
1308 *errors = 0;
1309 }
1310 else {
1311 errors = &discard_errors;
1312 }
a0dbb045 1313
eb83ed87
KW
1314 /* The order of malformation tests here is important. We should consume as
1315 * few bytes as possible in order to not skip any valid character. This is
1316 * required by the Unicode Standard (section 3.9 of Unicode 6.0); see also
1317 * http://unicode.org/reports/tr36 for more discussion as to why. For
1318 * example, once we've done a UTF8SKIP, we can tell the expected number of
1319 * bytes, and could fail right off the bat if the input parameters indicate
1320 * that there are too few available. But it could be that just that first
1321 * byte is garbled, and the intended character occupies fewer bytes. If we
1322 * blindly assumed that the first byte is correct, and skipped based on
1323 * that number, we could skip over a valid input character. So instead, we
1324 * always examine the sequence byte-by-byte.
1325 *
1326 * We also should not consume too few bytes, otherwise someone could inject
1327 * things. For example, an input could be deliberately designed to
1328 * overflow, and if this code bailed out immediately upon discovering that,
e2660c54 1329 * returning to the caller C<*retlen> pointing to the very next byte (one
eb83ed87
KW
1330 * which is actually part of of the overflowing sequence), that could look
1331 * legitimate to the caller, which could discard the initial partial
2b5e7bc2
KW
1332 * sequence and process the rest, inappropriately.
1333 *
1334 * Some possible input sequences are malformed in more than one way. This
1335 * function goes to lengths to try to find all of them. This is necessary
1336 * for correctness, as the inputs may allow one malformation but not
1337 * another, and if we abandon searching for others after finding the
1338 * allowed one, we could allow in something that shouldn't have been.
1339 */
eb83ed87 1340
b5b9af04 1341 if (UNLIKELY(curlen == 0)) {
2b5e7bc2
KW
1342 possible_problems |= UTF8_GOT_EMPTY;
1343 curlen = 0;
5a48568d 1344 uv = UNICODE_REPLACEMENT;
2b5e7bc2 1345 goto ready_to_handle_errors;
0c443dc2
JH
1346 }
1347
eb83ed87
KW
1348 expectlen = UTF8SKIP(s);
1349
1350 /* A well-formed UTF-8 character, as the vast majority of calls to this
1351 * function will be for, has this expected length. For efficiency, set
1352 * things up here to return it. It will be overriden only in those rare
1353 * cases where a malformation is found */
1354 if (retlen) {
1355 *retlen = expectlen;
1356 }
1357
1358 /* An invariant is trivially well-formed */
1d72bdf6 1359 if (UTF8_IS_INVARIANT(uv)) {
de69f3af 1360 return uv;
a0ed51b3 1361 }
67e989fb 1362
eb83ed87 1363 /* A continuation character can't start a valid sequence */
b5b9af04 1364 if (UNLIKELY(UTF8_IS_CONTINUATION(uv))) {
2b5e7bc2
KW
1365 possible_problems |= UTF8_GOT_CONTINUATION;
1366 curlen = 1;
1367 uv = UNICODE_REPLACEMENT;
1368 goto ready_to_handle_errors;
ba210ebe 1369 }
9041c2e3 1370
dcd27b3c 1371 /* Here is not a continuation byte, nor an invariant. The only thing left
ddb65933
KW
1372 * is a start byte (possibly for an overlong). (We can't use UTF8_IS_START
1373 * because it excludes start bytes like \xC0 that always lead to
1374 * overlongs.) */
dcd27b3c 1375
534752c1
KW
1376 /* Convert to I8 on EBCDIC (no-op on ASCII), then remove the leading bits
1377 * that indicate the number of bytes in the character's whole UTF-8
1378 * sequence, leaving just the bits that are part of the value. */
1379 uv = NATIVE_UTF8_TO_I8(uv) & UTF_START_MASK(expectlen);
ba210ebe 1380
e308b348
KW
1381 /* Setup the loop end point, making sure to not look past the end of the
1382 * input string, and flag it as too short if the size isn't big enough. */
1383 send = (U8*) s0;
1384 if (UNLIKELY(curlen < expectlen)) {
1385 possible_problems |= UTF8_GOT_SHORT;
1386 avail_len = curlen;
1387 send += curlen;
1388 }
1389 else {
1390 send += expectlen;
1391 }
e308b348 1392
eb83ed87 1393 /* Now, loop through the remaining bytes in the character's sequence,
e308b348 1394 * accumulating each into the working value as we go. */
eb83ed87 1395 for (s = s0 + 1; s < send; s++) {
b5b9af04 1396 if (LIKELY(UTF8_IS_CONTINUATION(*s))) {
8850bf83 1397 uv = UTF8_ACCUMULATE(uv, *s);
2b5e7bc2
KW
1398 continue;
1399 }
1400
1401 /* Here, found a non-continuation before processing all expected bytes.
1402 * This byte indicates the beginning of a new character, so quit, even
1403 * if allowing this malformation. */
2b5e7bc2 1404 possible_problems |= UTF8_GOT_NON_CONTINUATION;
e308b348 1405 break;
eb83ed87
KW
1406 } /* End of loop through the character's bytes */
1407
1408 /* Save how many bytes were actually in the character */
1409 curlen = s - s0;
1410
2b5e7bc2
KW
1411 /* Note that there are two types of too-short malformation. One is when
1412 * there is actual wrong data before the normal termination of the
1413 * sequence. The other is that the sequence wasn't complete before the end
1414 * of the data we are allowed to look at, based on the input 'curlen'.
1415 * This means that we were passed data for a partial character, but it is
1416 * valid as far as we saw. The other is definitely invalid. This
1417 * distinction could be important to a caller, so the two types are kept
15b010f0
KW
1418 * separate.
1419 *
1420 * A convenience macro that matches either of the too-short conditions. */
1421# define UTF8_GOT_TOO_SHORT (UTF8_GOT_SHORT|UTF8_GOT_NON_CONTINUATION)
1422
1423 if (UNLIKELY(possible_problems & UTF8_GOT_TOO_SHORT)) {
1424 uv_so_far = uv;
1425 uv = UNICODE_REPLACEMENT;
1426 }
2b5e7bc2 1427
08e73697
KW
1428 /* Check for overflow. The algorithm requires us to not look past the end
1429 * of the current character, even if partial, so the upper limit is 's' */
e050c007
KW
1430 if (UNLIKELY(0 < does_utf8_overflow(s0, s,
1431 1 /* Do consider overlongs */
1432 )))
1433 {
2b5e7bc2
KW
1434 possible_problems |= UTF8_GOT_OVERFLOW;
1435 uv = UNICODE_REPLACEMENT;
eb83ed87 1436 }
eb83ed87 1437
2b5e7bc2
KW
1438 /* Check for overlong. If no problems so far, 'uv' is the correct code
1439 * point value. Simply see if it is expressible in fewer bytes. Otherwise
1440 * we must look at the UTF-8 byte sequence itself to see if it is for an
1441 * overlong */
1442 if ( ( LIKELY(! possible_problems)
1443 && UNLIKELY(expectlen > (STRLEN) OFFUNISKIP(uv)))
56576a04 1444 || ( UNLIKELY(possible_problems)
2b5e7bc2
KW
1445 && ( UNLIKELY(! UTF8_IS_START(*s0))
1446 || ( curlen > 1
d6be65ae 1447 && UNLIKELY(0 < is_utf8_overlong_given_start_byte_ok(s0,
08e73697 1448 s - s0))))))
2f8f112e 1449 {
2b5e7bc2
KW
1450 possible_problems |= UTF8_GOT_LONG;
1451
abc28b54 1452 if ( UNLIKELY( possible_problems & UTF8_GOT_TOO_SHORT)
56576a04 1453
abc28b54
KW
1454 /* The calculation in the 'true' branch of this 'if'
1455 * below won't work if overflows, and isn't needed
1456 * anyway. Further below we handle all overflow
1457 * cases */
1458 && LIKELY(! (possible_problems & UTF8_GOT_OVERFLOW)))
1459 {
2b5e7bc2
KW
1460 UV min_uv = uv_so_far;
1461 STRLEN i;
1462
1463 /* Here, the input is both overlong and is missing some trailing
1464 * bytes. There is no single code point it could be for, but there
1465 * may be enough information present to determine if what we have
1466 * so far is for an unallowed code point, such as for a surrogate.
56576a04
KW
1467 * The code further below has the intelligence to determine this,
1468 * but just for non-overlong UTF-8 sequences. What we do here is
1469 * calculate the smallest code point the input could represent if
1470 * there were no too short malformation. Then we compute and save
1471 * the UTF-8 for that, which is what the code below looks at
1472 * instead of the raw input. It turns out that the smallest such
1473 * code point is all we need. */
2b5e7bc2
KW
1474 for (i = curlen; i < expectlen; i++) {
1475 min_uv = UTF8_ACCUMULATE(min_uv,
1476 I8_TO_NATIVE_UTF8(UTF_CONTINUATION_MARK));
1477 }
1478
e9f2c446 1479 adjusted_s0 = temp_char_buf;
57ff5f59 1480 (void) uvoffuni_to_utf8_flags(adjusted_s0, min_uv, 0);
2b5e7bc2 1481 }
eb83ed87
KW
1482 }
1483
56576a04
KW
1484 /* Here, we have found all the possible problems, except for when the input
1485 * is for a problematic code point not allowed by the input parameters. */
1486
06188866
KW
1487 /* uv is valid for overlongs */
1488 if ( ( ( LIKELY(! (possible_problems & ~UTF8_GOT_LONG))
1489
1490 /* isn't problematic if < this */
1491 && uv >= UNICODE_SURROGATE_FIRST)
2b5e7bc2 1492 || ( UNLIKELY(possible_problems)
d60baaa7
KW
1493
1494 /* if overflow, we know without looking further
1495 * precisely which of the problematic types it is,
1496 * and we deal with those in the overflow handling
1497 * code */
1498 && LIKELY(! (possible_problems & UTF8_GOT_OVERFLOW))
57ff5f59
KW
1499 && ( isUTF8_POSSIBLY_PROBLEMATIC(*adjusted_s0)
1500 || UNLIKELY(isUTF8_PERL_EXTENDED(s0)))))
760c7c2f
KW
1501 && ((flags & ( UTF8_DISALLOW_NONCHAR
1502 |UTF8_DISALLOW_SURROGATE
1503 |UTF8_DISALLOW_SUPER
d044b7a7 1504 |UTF8_DISALLOW_PERL_EXTENDED
760c7c2f
KW
1505 |UTF8_WARN_NONCHAR
1506 |UTF8_WARN_SURROGATE
1507 |UTF8_WARN_SUPER
d22ec717 1508 |UTF8_WARN_PERL_EXTENDED))))
eb83ed87 1509 {
2b5e7bc2
KW
1510 /* If there were no malformations, or the only malformation is an
1511 * overlong, 'uv' is valid */
1512 if (LIKELY(! (possible_problems & ~UTF8_GOT_LONG))) {
1513 if (UNLIKELY(UNICODE_IS_SURROGATE(uv))) {
1514 possible_problems |= UTF8_GOT_SURROGATE;
1515 }
1516 else if (UNLIKELY(uv > PERL_UNICODE_MAX)) {
1517 possible_problems |= UTF8_GOT_SUPER;
1518 }
1519 else if (UNLIKELY(UNICODE_IS_NONCHAR(uv))) {
1520 possible_problems |= UTF8_GOT_NONCHAR;
1521 }
1522 }
1523 else { /* Otherwise, need to look at the source UTF-8, possibly
1524 adjusted to be non-overlong */
1525
1526 if (UNLIKELY(NATIVE_UTF8_TO_I8(*adjusted_s0)
1527 >= FIRST_START_BYTE_THAT_IS_DEFINITELY_SUPER))
ea5ced44 1528 {
2b5e7bc2
KW
1529 possible_problems |= UTF8_GOT_SUPER;
1530 }
1531 else if (curlen > 1) {
1532 if (UNLIKELY(IS_UTF8_2_BYTE_SUPER(
1533 NATIVE_UTF8_TO_I8(*adjusted_s0),
1534 NATIVE_UTF8_TO_I8(*(adjusted_s0 + 1)))))
ea5ced44 1535 {
2b5e7bc2 1536 possible_problems |= UTF8_GOT_SUPER;
ea5ced44 1537 }
2b5e7bc2
KW
1538 else if (UNLIKELY(IS_UTF8_2_BYTE_SURROGATE(
1539 NATIVE_UTF8_TO_I8(*adjusted_s0),
1540 NATIVE_UTF8_TO_I8(*(adjusted_s0 + 1)))))
1541 {
1542 possible_problems |= UTF8_GOT_SURROGATE;
ea5ced44
KW
1543 }
1544 }
c0236afe 1545
2b5e7bc2
KW
1546 /* We need a complete well-formed UTF-8 character to discern
1547 * non-characters, so can't look for them here */
1548 }
1549 }
949cf498 1550
2b5e7bc2
KW
1551 ready_to_handle_errors:
1552
1553 /* At this point:
1554 * curlen contains the number of bytes in the sequence that
1555 * this call should advance the input by.
e308b348
KW
1556 * avail_len gives the available number of bytes passed in, but
1557 * only if this is less than the expected number of
1558 * bytes, based on the code point's start byte.
2b5e7bc2
KW
1559 * possible_problems' is 0 if there weren't any problems; otherwise a bit
1560 * is set in it for each potential problem found.
1561 * uv contains the code point the input sequence
1562 * represents; or if there is a problem that prevents
1563 * a well-defined value from being computed, it is
1564 * some subsitute value, typically the REPLACEMENT
1565 * CHARACTER.
1566 * s0 points to the first byte of the character
56576a04
KW
1567 * s points to just after were we left off processing
1568 * the character
1569 * send points to just after where that character should
1570 * end, based on how many bytes the start byte tells
1571 * us should be in it, but no further than s0 +
1572 * avail_len
2b5e7bc2 1573 */
eb83ed87 1574
2b5e7bc2
KW
1575 if (UNLIKELY(possible_problems)) {
1576 bool disallowed = FALSE;
1577 const U32 orig_problems = possible_problems;
1578
1579 while (possible_problems) { /* Handle each possible problem */
1580 UV pack_warn = 0;
1581 char * message = NULL;
1582
1583 /* Each 'if' clause handles one problem. They are ordered so that
1584 * the first ones' messages will be displayed before the later
6c64cd9d
KW
1585 * ones; this is kinda in decreasing severity order. But the
1586 * overlong must come last, as it changes 'uv' looked at by the
1587 * others */
2b5e7bc2
KW
1588 if (possible_problems & UTF8_GOT_OVERFLOW) {
1589
56576a04
KW
1590 /* Overflow means also got a super and are using Perl's
1591 * extended UTF-8, but we handle all three cases here */
2b5e7bc2 1592 possible_problems
d044b7a7 1593 &= ~(UTF8_GOT_OVERFLOW|UTF8_GOT_SUPER|UTF8_GOT_PERL_EXTENDED);
f9380377
KW
1594 *errors |= UTF8_GOT_OVERFLOW;
1595
1596 /* But the API says we flag all errors found */
1597 if (flags & (UTF8_WARN_SUPER|UTF8_DISALLOW_SUPER)) {
1598 *errors |= UTF8_GOT_SUPER;
1599 }
ddb65933 1600 if (flags
d044b7a7 1601 & (UTF8_WARN_PERL_EXTENDED|UTF8_DISALLOW_PERL_EXTENDED))
ddb65933 1602 {
d044b7a7 1603 *errors |= UTF8_GOT_PERL_EXTENDED;
f9380377 1604 }
2b5e7bc2 1605
d60baaa7 1606 /* Disallow if any of the three categories say to */
56576a04 1607 if ( ! (flags & UTF8_ALLOW_OVERFLOW)
d60baaa7 1608 || (flags & ( UTF8_DISALLOW_SUPER
d044b7a7 1609 |UTF8_DISALLOW_PERL_EXTENDED)))
d60baaa7
KW
1610 {
1611 disallowed = TRUE;
1612 }
1613
d22ec717
KW
1614 /* Likewise, warn if any say to */
1615 if ( ! (flags & UTF8_ALLOW_OVERFLOW)
1616 || (flags & (UTF8_WARN_SUPER|UTF8_WARN_PERL_EXTENDED)))
d60baaa7 1617 {
2b5e7bc2 1618
ddb65933
KW
1619 /* The warnings code explicitly says it doesn't handle the
1620 * case of packWARN2 and two categories which have
1621 * parent-child relationship. Even if it works now to
1622 * raise the warning if either is enabled, it wouldn't
1623 * necessarily do so in the future. We output (only) the
56576a04 1624 * most dire warning */
ddb65933
KW
1625 if (! (flags & UTF8_CHECK_ONLY)) {
1626 if (ckWARN_d(WARN_UTF8)) {
1627 pack_warn = packWARN(WARN_UTF8);
1628 }
1629 else if (ckWARN_d(WARN_NON_UNICODE)) {
1630 pack_warn = packWARN(WARN_NON_UNICODE);
1631 }
1632 if (pack_warn) {
1633 message = Perl_form(aTHX_ "%s: %s (overflows)",
1634 malformed_text,
05b9033b 1635 _byte_dump_string(s0, curlen, 0));
ddb65933 1636 }
2b5e7bc2
KW
1637 }
1638 }
1639 }
1640 else if (possible_problems & UTF8_GOT_EMPTY) {
1641 possible_problems &= ~UTF8_GOT_EMPTY;
f9380377 1642 *errors |= UTF8_GOT_EMPTY;
2b5e7bc2
KW
1643
1644 if (! (flags & UTF8_ALLOW_EMPTY)) {
d1f8d421
KW
1645
1646 /* This so-called malformation is now treated as a bug in
1647 * the caller. If you have nothing to decode, skip calling
1648 * this function */
1649 assert(0);
1650
2b5e7bc2
KW
1651 disallowed = TRUE;
1652 if (ckWARN_d(WARN_UTF8) && ! (flags & UTF8_CHECK_ONLY)) {
1653 pack_warn = packWARN(WARN_UTF8);
1654 message = Perl_form(aTHX_ "%s (empty string)",
1655 malformed_text);
1656 }
1657 }
1658 }
1659 else if (possible_problems & UTF8_GOT_CONTINUATION) {
1660 possible_problems &= ~UTF8_GOT_CONTINUATION;
f9380377 1661 *errors |= UTF8_GOT_CONTINUATION;
2b5e7bc2
KW
1662
1663 if (! (flags & UTF8_ALLOW_CONTINUATION)) {
1664 disallowed = TRUE;
1665 if (ckWARN_d(WARN_UTF8) && ! (flags & UTF8_CHECK_ONLY)) {
1666 pack_warn = packWARN(WARN_UTF8);
1667 message = Perl_form(aTHX_
1668 "%s: %s (unexpected continuation byte 0x%02x,"
1669 " with no preceding start byte)",
1670 malformed_text,
7e2f38b2 1671 _byte_dump_string(s0, 1, 0), *s0);
2b5e7bc2
KW
1672 }
1673 }
1674 }
2b5e7bc2
KW
1675 else if (possible_problems & UTF8_GOT_SHORT) {
1676 possible_problems &= ~UTF8_GOT_SHORT;
f9380377 1677 *errors |= UTF8_GOT_SHORT;
2b5e7bc2
KW
1678
1679 if (! (flags & UTF8_ALLOW_SHORT)) {
1680 disallowed = TRUE;
1681 if (ckWARN_d(WARN_UTF8) && ! (flags & UTF8_CHECK_ONLY)) {
1682 pack_warn = packWARN(WARN_UTF8);
1683 message = Perl_form(aTHX_
56576a04
KW
1684 "%s: %s (too short; %d byte%s available, need %d)",
1685 malformed_text,
1686 _byte_dump_string(s0, send - s0, 0),
1687 (int)avail_len,
1688 avail_len == 1 ? "" : "s",
1689 (int)expectlen);
2b5e7bc2
KW
1690 }
1691 }
ba210ebe 1692
2b5e7bc2 1693 }
e308b348
KW
1694 else if (possible_problems & UTF8_GOT_NON_CONTINUATION) {
1695 possible_problems &= ~UTF8_GOT_NON_CONTINUATION;
1696 *errors |= UTF8_GOT_NON_CONTINUATION;
1697
1698 if (! (flags & UTF8_ALLOW_NON_CONTINUATION)) {
1699 disallowed = TRUE;
1700 if (ckWARN_d(WARN_UTF8) && ! (flags & UTF8_CHECK_ONLY)) {
99a765e9
KW
1701
1702 /* If we don't know for sure that the input length is
1703 * valid, avoid as much as possible reading past the
1704 * end of the buffer */
1705 int printlen = (flags & _UTF8_NO_CONFIDENCE_IN_CURLEN)
1706 ? s - s0
1707 : send - s0;
e308b348
KW
1708 pack_warn = packWARN(WARN_UTF8);
1709 message = Perl_form(aTHX_ "%s",
1710 unexpected_non_continuation_text(s0,
99a765e9 1711 printlen,
e308b348
KW
1712 s - s0,
1713 (int) expectlen));
1714 }
1715 }
1716 }
2b5e7bc2
KW
1717 else if (possible_problems & UTF8_GOT_SURROGATE) {
1718 possible_problems &= ~UTF8_GOT_SURROGATE;
1719
f9380377
KW
1720 if (flags & UTF8_WARN_SURROGATE) {
1721 *errors |= UTF8_GOT_SURROGATE;
1722
1723 if ( ! (flags & UTF8_CHECK_ONLY)
1724 && ckWARN_d(WARN_SURROGATE))
1725 {
2b5e7bc2
KW
1726 pack_warn = packWARN(WARN_SURROGATE);
1727
1728 /* These are the only errors that can occur with a
1729 * surrogate when the 'uv' isn't valid */
1730 if (orig_problems & UTF8_GOT_TOO_SHORT) {
1731 message = Perl_form(aTHX_
1732 "UTF-16 surrogate (any UTF-8 sequence that"
1733 " starts with \"%s\" is for a surrogate)",
7e2f38b2 1734 _byte_dump_string(s0, curlen, 0));
2b5e7bc2
KW
1735 }
1736 else {
c94c2f39 1737 message = Perl_form(aTHX_ surrogate_cp_format, uv);
2b5e7bc2 1738 }
f9380377 1739 }
2b5e7bc2 1740 }
ba210ebe 1741
2b5e7bc2
KW
1742 if (flags & UTF8_DISALLOW_SURROGATE) {
1743 disallowed = TRUE;
f9380377 1744 *errors |= UTF8_GOT_SURROGATE;
2b5e7bc2
KW
1745 }
1746 }
1747 else if (possible_problems & UTF8_GOT_SUPER) {
1748 possible_problems &= ~UTF8_GOT_SUPER;
949cf498 1749
f9380377
KW
1750 if (flags & UTF8_WARN_SUPER) {
1751 *errors |= UTF8_GOT_SUPER;
1752
1753 if ( ! (flags & UTF8_CHECK_ONLY)
1754 && ckWARN_d(WARN_NON_UNICODE))
1755 {
2b5e7bc2
KW
1756 pack_warn = packWARN(WARN_NON_UNICODE);
1757
1758 if (orig_problems & UTF8_GOT_TOO_SHORT) {
1759 message = Perl_form(aTHX_
1760 "Any UTF-8 sequence that starts with"
1761 " \"%s\" is for a non-Unicode code point,"
1762 " may not be portable",
7e2f38b2 1763 _byte_dump_string(s0, curlen, 0));
2b5e7bc2
KW
1764 }
1765 else {
c94c2f39 1766 message = Perl_form(aTHX_ super_cp_format, uv);
2b5e7bc2 1767 }
f9380377 1768 }
2b5e7bc2 1769 }
ba210ebe 1770
57ff5f59
KW
1771 /* Test for Perl's extended UTF-8 after the regular SUPER ones,
1772 * and before possibly bailing out, so that the more dire
1773 * warning will override the regular one. */
1774 if (UNLIKELY(isUTF8_PERL_EXTENDED(s0))) {
2b5e7bc2 1775 if ( ! (flags & UTF8_CHECK_ONLY)
d044b7a7 1776 && (flags & (UTF8_WARN_PERL_EXTENDED|UTF8_WARN_SUPER))
db0f09e6 1777 && ckWARN_d(WARN_NON_UNICODE))
2b5e7bc2 1778 {
db0f09e6 1779 pack_warn = packWARN(WARN_NON_UNICODE);
2b5e7bc2 1780
57ff5f59
KW
1781 /* If it is an overlong that evaluates to a code point
1782 * that doesn't have to use the Perl extended UTF-8, it
1783 * still used it, and so we output a message that
1784 * doesn't refer to the code point. The same is true
1785 * if there was a SHORT malformation where the code
1786 * point is not valid. In that case, 'uv' will have
1787 * been set to the REPLACEMENT CHAR, and the message
1788 * below without the code point in it will be selected
1789 * */
1790 if (UNICODE_IS_PERL_EXTENDED(uv)) {
2b5e7bc2 1791 message = Perl_form(aTHX_
57ff5f59 1792 perl_extended_cp_format, uv);
2b5e7bc2
KW
1793 }
1794 else {
1795 message = Perl_form(aTHX_
57ff5f59
KW
1796 "Any UTF-8 sequence that starts with"
1797 " \"%s\" is a Perl extension, and"
1798 " so is not portable",
1799 _byte_dump_string(s0, curlen, 0));
2b5e7bc2
KW
1800 }
1801 }
1802
d044b7a7
KW
1803 if (flags & ( UTF8_WARN_PERL_EXTENDED
1804 |UTF8_DISALLOW_PERL_EXTENDED))
ddb65933 1805 {
d044b7a7 1806 *errors |= UTF8_GOT_PERL_EXTENDED;
f9380377 1807
d044b7a7 1808 if (flags & UTF8_DISALLOW_PERL_EXTENDED) {
f9380377
KW
1809 disallowed = TRUE;
1810 }
2b5e7bc2
KW
1811 }
1812 }
eb83ed87 1813
2b5e7bc2 1814 if (flags & UTF8_DISALLOW_SUPER) {
f9380377 1815 *errors |= UTF8_GOT_SUPER;
2b5e7bc2
KW
1816 disallowed = TRUE;
1817 }
2b5e7bc2
KW
1818 }
1819 else if (possible_problems & UTF8_GOT_NONCHAR) {
1820 possible_problems &= ~UTF8_GOT_NONCHAR;
ba210ebe 1821
f9380377
KW
1822 if (flags & UTF8_WARN_NONCHAR) {
1823 *errors |= UTF8_GOT_NONCHAR;
1824
1825 if ( ! (flags & UTF8_CHECK_ONLY)
1826 && ckWARN_d(WARN_NONCHAR))
1827 {
2b5e7bc2
KW
1828 /* The code above should have guaranteed that we don't
1829 * get here with errors other than overlong */
1830 assert (! (orig_problems
1831 & ~(UTF8_GOT_LONG|UTF8_GOT_NONCHAR)));
1832
1833 pack_warn = packWARN(WARN_NONCHAR);
c94c2f39 1834 message = Perl_form(aTHX_ nonchar_cp_format, uv);
f9380377 1835 }
2b5e7bc2 1836 }
5b311467 1837
2b5e7bc2
KW
1838 if (flags & UTF8_DISALLOW_NONCHAR) {
1839 disallowed = TRUE;
f9380377 1840 *errors |= UTF8_GOT_NONCHAR;
2b5e7bc2 1841 }
6c64cd9d
KW
1842 }
1843 else if (possible_problems & UTF8_GOT_LONG) {
1844 possible_problems &= ~UTF8_GOT_LONG;
1845 *errors |= UTF8_GOT_LONG;
1846
1847 if (flags & UTF8_ALLOW_LONG) {
1848
1849 /* We don't allow the actual overlong value, unless the
1850 * special extra bit is also set */
1851 if (! (flags & ( UTF8_ALLOW_LONG_AND_ITS_VALUE
1852 & ~UTF8_ALLOW_LONG)))
1853 {
1854 uv = UNICODE_REPLACEMENT;
1855 }
1856 }
1857 else {
1858 disallowed = TRUE;
1859
1860 if (ckWARN_d(WARN_UTF8) && ! (flags & UTF8_CHECK_ONLY)) {
1861 pack_warn = packWARN(WARN_UTF8);
1862
1863 /* These error types cause 'uv' to be something that
1864 * isn't what was intended, so can't use it in the
1865 * message. The other error types either can't
1866 * generate an overlong, or else the 'uv' is valid */
1867 if (orig_problems &
1868 (UTF8_GOT_TOO_SHORT|UTF8_GOT_OVERFLOW))
1869 {
1870 message = Perl_form(aTHX_
1871 "%s: %s (any UTF-8 sequence that starts"
1872 " with \"%s\" is overlong which can and"
1873 " should be represented with a"
1874 " different, shorter sequence)",
1875 malformed_text,
1876 _byte_dump_string(s0, send - s0, 0),
1877 _byte_dump_string(s0, curlen, 0));
1878 }
1879 else {
1880 U8 tmpbuf[UTF8_MAXBYTES+1];
1be62ab9
KW
1881 const U8 * const e = uvoffuni_to_utf8_flags(tmpbuf,
1882 uv, 0);
d819dc50
KW
1883 /* Don't use U+ for non-Unicode code points, which
1884 * includes those in the Latin1 range */
1885 const char * preface = ( uv > PERL_UNICODE_MAX
1886#ifdef EBCDIC
1887 || uv <= 0xFF
1888#endif
1889 )
1890 ? "0x"
1891 : "U+";
6c64cd9d
KW
1892 message = Perl_form(aTHX_
1893 "%s: %s (overlong; instead use %s to represent"
1894 " %s%0*" UVXf ")",
1895 malformed_text,
1896 _byte_dump_string(s0, send - s0, 0),
1897 _byte_dump_string(tmpbuf, e - tmpbuf, 0),
1898 preface,
1899 ((uv < 256) ? 2 : 4), /* Field width of 2 for
1900 small code points */
1be62ab9 1901 UNI_TO_NATIVE(uv));
6c64cd9d
KW
1902 }
1903 }
1904 }
2b5e7bc2
KW
1905 } /* End of looking through the possible flags */
1906
1907 /* Display the message (if any) for the problem being handled in
1908 * this iteration of the loop */
1909 if (message) {
1910 if (PL_op)
1911 Perl_warner(aTHX_ pack_warn, "%s in %s", message,
1912 OP_DESC(PL_op));
1913 else
1914 Perl_warner(aTHX_ pack_warn, "%s", message);
1915 }
ddb65933 1916 } /* End of 'while (possible_problems)' */
a0dbb045 1917
2b5e7bc2
KW
1918 /* Since there was a possible problem, the returned length may need to
1919 * be changed from the one stored at the beginning of this function.
1920 * Instead of trying to figure out if that's needed, just do it. */
1921 if (retlen) {
1922 *retlen = curlen;
1923 }
a0dbb045 1924
2b5e7bc2
KW
1925 if (disallowed) {
1926 if (flags & UTF8_CHECK_ONLY && retlen) {
1927 *retlen = ((STRLEN) -1);
1928 }
1929 return 0;
1930 }
eb83ed87 1931 }
ba210ebe 1932
2b5e7bc2 1933 return UNI_TO_NATIVE(uv);
a0ed51b3
LW
1934}
1935
8e84507e 1936/*
ec5f19d0
KW
1937=for apidoc utf8_to_uvchr_buf
1938
1939Returns the native code point of the first character in the string C<s> which
1940is assumed to be in UTF-8 encoding; C<send> points to 1 beyond the end of C<s>.
524080c4 1941C<*retlen> will be set to the length, in bytes, of that character.
ec5f19d0 1942
524080c4
KW
1943If C<s> does not point to a well-formed UTF-8 character and UTF8 warnings are
1944enabled, zero is returned and C<*retlen> is set (if C<retlen> isn't
796b6530 1945C<NULL>) to -1. If those warnings are off, the computed value, if well-defined
173db420 1946(or the Unicode REPLACEMENT CHARACTER if not), is silently returned, and
796b6530 1947C<*retlen> is set (if C<retlen> isn't C<NULL>) so that (S<C<s> + C<*retlen>>) is
173db420 1948the next possible position in C<s> that could begin a non-malformed character.
de69f3af 1949See L</utf8n_to_uvchr> for details on when the REPLACEMENT CHARACTER is
173db420 1950returned.
ec5f19d0
KW
1951
1952=cut
52be2536
KW
1953
1954Also implemented as a macro in utf8.h
1955
ec5f19d0
KW
1956*/
1957
1958
1959UV
1960Perl_utf8_to_uvchr_buf(pTHX_ const U8 *s, const U8 *send, STRLEN *retlen)
1961{
7f974d7e
KW
1962 PERL_ARGS_ASSERT_UTF8_TO_UVCHR_BUF;
1963
ec5f19d0
KW
1964 assert(s < send);
1965
1966 return utf8n_to_uvchr(s, send - s, retlen,
ddb65933 1967 ckWARN_d(WARN_UTF8) ? 0 : UTF8_ALLOW_ANY);
ec5f19d0
KW
1968}
1969
52be2536
KW
1970/* This is marked as deprecated
1971 *
ec5f19d0
KW
1972=for apidoc utf8_to_uvuni_buf
1973
de69f3af
KW
1974Only in very rare circumstances should code need to be dealing in Unicode
1975(as opposed to native) code points. In those few cases, use
1976C<L<NATIVE_TO_UNI(utf8_to_uvchr_buf(...))|/utf8_to_uvchr_buf>> instead.
4f83cdcd
KW
1977
1978Returns the Unicode (not-native) code point of the first character in the
1979string C<s> which
ec5f19d0
KW
1980is assumed to be in UTF-8 encoding; C<send> points to 1 beyond the end of C<s>.
1981C<retlen> will be set to the length, in bytes, of that character.
1982
524080c4
KW
1983If C<s> does not point to a well-formed UTF-8 character and UTF8 warnings are
1984enabled, zero is returned and C<*retlen> is set (if C<retlen> isn't
1985NULL) to -1. If those warnings are off, the computed value if well-defined (or
1986the Unicode REPLACEMENT CHARACTER, if not) is silently returned, and C<*retlen>
1987is set (if C<retlen> isn't NULL) so that (S<C<s> + C<*retlen>>) is the
1988next possible position in C<s> that could begin a non-malformed character.
de69f3af 1989See L</utf8n_to_uvchr> for details on when the REPLACEMENT CHARACTER is returned.
ec5f19d0
KW
1990
1991=cut
1992*/
1993
1994UV
1995Perl_utf8_to_uvuni_buf(pTHX_ const U8 *s, const U8 *send, STRLEN *retlen)
1996{
1997 PERL_ARGS_ASSERT_UTF8_TO_UVUNI_BUF;
1998
1999 assert(send > s);
2000
5962d97e 2001 return NATIVE_TO_UNI(utf8_to_uvchr_buf(s, send, retlen));
ec5f19d0
KW
2002}
2003
b76347f2 2004/*
87cea99e 2005=for apidoc utf8_length
b76347f2 2006
b2e7ed74
KW
2007Returns the number of characters in the sequence of UTF-8-encoded bytes starting
2008at C<s> and ending at the byte just before C<e>. If <s> and <e> point to the
2009same place, it returns 0 with no warning raised.
2010
2011If C<e E<lt> s> or if the scan would end up past C<e>, it raises a UTF8 warning
2012and returns the number of valid characters.
b76347f2
JH
2013
2014=cut
2015*/
2016
2017STRLEN
35a4481c 2018Perl_utf8_length(pTHX_ const U8 *s, const U8 *e)
b76347f2
JH
2019{
2020 STRLEN len = 0;
2021
7918f24d
NC
2022 PERL_ARGS_ASSERT_UTF8_LENGTH;
2023
8850bf83
JH
2024 /* Note: cannot use UTF8_IS_...() too eagerly here since e.g.
2025 * the bitops (especially ~) can create illegal UTF-8.
2026 * In other words: in Perl UTF-8 is not just for Unicode. */
2027
a3b680e6
AL
2028 if (e < s)
2029 goto warn_and_return;
b76347f2 2030 while (s < e) {
4cbf4130 2031 s += UTF8SKIP(s);
8e91ec7f
AV
2032 len++;
2033 }
2034
2035 if (e != s) {
2036 len--;
2037 warn_and_return:
9b387841
NC
2038 if (PL_op)
2039 Perl_ck_warner_d(aTHX_ packWARN(WARN_UTF8),
2040 "%s in %s", unees, OP_DESC(PL_op));
2041 else
61a12c31 2042 Perl_ck_warner_d(aTHX_ packWARN(WARN_UTF8), "%s", unees);
b76347f2
JH
2043 }
2044
2045 return len;
2046}
2047
b06226ff 2048/*
fed3ba5d
NC
2049=for apidoc bytes_cmp_utf8
2050
a1433954 2051Compares the sequence of characters (stored as octets) in C<b>, C<blen> with the
72d33970
FC
2052sequence of characters (stored as UTF-8)
2053in C<u>, C<ulen>. Returns 0 if they are
fed3ba5d
NC
2054equal, -1 or -2 if the first string is less than the second string, +1 or +2
2055if the first string is greater than the second string.
2056
2057-1 or +1 is returned if the shorter string was identical to the start of the
72d33970
FC
2058longer string. -2 or +2 is returned if
2059there was a difference between characters
fed3ba5d
NC
2060within the strings.
2061
2062=cut
2063*/
2064
2065int
2066Perl_bytes_cmp_utf8(pTHX_ const U8 *b, STRLEN blen, const U8 *u, STRLEN ulen)
2067{
2068 const U8 *const bend = b + blen;
2069 const U8 *const uend = u + ulen;
2070
2071 PERL_ARGS_ASSERT_BYTES_CMP_UTF8;
fed3ba5d
NC
2072
2073 while (b < bend && u < uend) {
2074 U8 c = *u++;
2075 if (!UTF8_IS_INVARIANT(c)) {
2076 if (UTF8_IS_DOWNGRADEABLE_START(c)) {
2077 if (u < uend) {
2078 U8 c1 = *u++;
2079 if (UTF8_IS_CONTINUATION(c1)) {
a62b247b 2080 c = EIGHT_BIT_UTF8_TO_NATIVE(c, c1);
fed3ba5d 2081 } else {
2b5e7bc2 2082 /* diag_listed_as: Malformed UTF-8 character%s */
fed3ba5d 2083 Perl_ck_warner_d(aTHX_ packWARN(WARN_UTF8),
56576a04
KW
2084 "%s %s%s",
2085 unexpected_non_continuation_text(u - 2, 2, 1, 2),
2086 PL_op ? " in " : "",
2087 PL_op ? OP_DESC(PL_op) : "");
fed3ba5d
NC
2088 return -2;
2089 }
2090 } else {
2091 if (PL_op)
2092 Perl_ck_warner_d(aTHX_ packWARN(WARN_UTF8),
2093 "%s in %s", unees, OP_DESC(PL_op));
2094 else
61a12c31 2095 Perl_ck_warner_d(aTHX_ packWARN(WARN_UTF8), "%s", unees);
fed3ba5d
NC
2096 return -2; /* Really want to return undef :-) */
2097 }
2098 } else {
2099 return -2;
2100 }
2101 }
2102 if (*b != c) {
2103 return *b < c ? -2 : +2;
2104 }
2105 ++b;
2106 }
2107
2108 if (b == bend && u == uend)
2109 return 0;
2110
2111 return b < bend ? +1 : -1;
2112}
2113
2114/*
87cea99e 2115=for apidoc utf8_to_bytes
6940069f 2116
3bc0c78c 2117Converts a string C<"s"> of length C<*lenp> from UTF-8 into native byte encoding.
a1433954 2118Unlike L</bytes_to_utf8>, this over-writes the original string, and
09af0336 2119updates C<*lenp> to contain the new length.
3bc0c78c
KW
2120Returns zero on failure (leaving C<"s"> unchanged) setting C<*lenp> to -1.
2121
2122Upon successful return, the number of variants in the string can be computed by
23b37b12
KW
2123having saved the value of C<*lenp> before the call, and subtracting the
2124after-call value of C<*lenp> from it.
6940069f 2125
a1433954 2126If you need a copy of the string, see L</bytes_from_utf8>.
95be277c 2127
6940069f
GS
2128=cut
2129*/
2130
2131U8 *
09af0336 2132Perl_utf8_to_bytes(pTHX_ U8 *s, STRLEN *lenp)
6940069f 2133{
9fe0d3c2 2134 U8 * first_variant;
246fae53 2135
7918f24d 2136 PERL_ARGS_ASSERT_UTF8_TO_BYTES;
81611534 2137 PERL_UNUSED_CONTEXT;
7918f24d 2138
9fe0d3c2 2139 /* This is a no-op if no variants at all in the input */
09af0336 2140 if (is_utf8_invariant_string_loc(s, *lenp, (const U8 **) &first_variant)) {
9fe0d3c2
KW
2141 return s;
2142 }
2143
2144 {
3c5aa262 2145 U8 * const save = s;
09af0336 2146 U8 * const send = s + *lenp;
3c5aa262
KW
2147 U8 * d;
2148
2149 /* Nothing before the first variant needs to be changed, so start the real
2150 * work there */
2151 s = first_variant;
2152 while (s < send) {
2153 if (! UTF8_IS_INVARIANT(*s)) {
2154 if (! UTF8_IS_NEXT_CHAR_DOWNGRADEABLE(s, send)) {
09af0336 2155 *lenp = ((STRLEN) -1);
3c5aa262
KW
2156 return 0;
2157 }
2158 s++;
d59937ca
KW
2159 }
2160 s++;
dcad2880 2161 }
dcad2880 2162
3c5aa262
KW
2163 /* Is downgradable, so do it */
2164 d = s = first_variant;
2165 while (s < send) {
2166 U8 c = *s++;
2167 if (! UVCHR_IS_INVARIANT(c)) {
2168 /* Then it is two-byte encoded */
2169 c = EIGHT_BIT_UTF8_TO_NATIVE(c, *s);
2170 s++;
2171 }
2172 *d++ = c;
2173 }
2174 *d = '\0';
09af0336 2175 *lenp = d - save;
3c5aa262
KW
2176
2177 return save;
9fe0d3c2 2178 }
6940069f
GS
2179}
2180
2181/*
87cea99e 2182=for apidoc bytes_from_utf8
f9a63242 2183
09af0336 2184Converts a potentially UTF-8 encoded string C<s> of length C<*lenp> into native
41ae6089 2185byte encoding. On input, the boolean C<*is_utf8p> gives whether or not C<s> is
4f3d592d
KW
2186actually encoded in UTF-8.
2187
2188Unlike L</utf8_to_bytes> but like L</bytes_to_utf8>, this is non-destructive of
2189the input string.
2190
41ae6089
KW
2191Do nothing if C<*is_utf8p> is 0, or if there are code points in the string
2192not expressible in native byte encoding. In these cases, C<*is_utf8p> and
09af0336 2193C<*lenp> are unchanged, and the return value is the original C<s>.
4f3d592d 2194
41ae6089 2195Otherwise, C<*is_utf8p> is set to 0, and the return value is a pointer to a
4f3d592d 2196newly created string containing a downgraded copy of C<s>, and whose length is
23b37b12 2197returned in C<*lenp>, updated. The new string is C<NUL>-terminated.
f9a63242 2198
3bc0c78c 2199Upon successful return, the number of variants in the string can be computed by
23b37b12
KW
2200having saved the value of C<*lenp> before the call, and subtracting the
2201after-call value of C<*lenp> from it.
3bc0c78c 2202
37607a96 2203=cut
976c1b08
KW
2204
2205There is a macro that avoids this function call, but this is retained for
2206anyone who calls it with the Perl_ prefix */
f9a63242
JH
2207
2208U8 *
41ae6089 2209Perl_bytes_from_utf8(pTHX_ const U8 *s, STRLEN *lenp, bool *is_utf8p)
f9a63242 2210{
7918f24d 2211 PERL_ARGS_ASSERT_BYTES_FROM_UTF8;
96a5add6 2212 PERL_UNUSED_CONTEXT;
f9a63242 2213
976c1b08
KW
2214 return bytes_from_utf8_loc(s, lenp, is_utf8p, NULL);
2215}
2216
2217/*
2218No = here because currently externally undocumented
2219for apidoc bytes_from_utf8_loc
2220
2221Like C<L</bytes_from_utf8>()>, but takes an extra parameter, a pointer to where
2222to store the location of the first character in C<"s"> that cannot be
2223converted to non-UTF8.
2224
2225If that parameter is C<NULL>, this function behaves identically to
2226C<bytes_from_utf8>.
2227
2228Otherwise if C<*is_utf8p> is 0 on input, the function behaves identically to
2229C<bytes_from_utf8>, except it also sets C<*first_non_downgradable> to C<NULL>.
2230
2231Otherwise, the function returns a newly created C<NUL>-terminated string
2232containing the non-UTF8 equivalent of the convertible first portion of
2233C<"s">. C<*lenp> is set to its length, not including the terminating C<NUL>.
2234If the entire input string was converted, C<*is_utf8p> is set to a FALSE value,
2235and C<*first_non_downgradable> is set to C<NULL>.
2236
2237Otherwise, C<*first_non_downgradable> set to point to the first byte of the
2238first character in the original string that wasn't converted. C<*is_utf8p> is
2239unchanged. Note that the new string may have length 0.
2240
2241Another way to look at it is, if C<*first_non_downgradable> is non-C<NULL> and
2242C<*is_utf8p> is TRUE, this function starts at the beginning of C<"s"> and
2243converts as many characters in it as possible stopping at the first one it
385b74be 2244finds that can't be converted to non-UTF-8. C<*first_non_downgradable> is
976c1b08
KW
2245set to point to that. The function returns the portion that could be converted
2246in a newly created C<NUL>-terminated string, and C<*lenp> is set to its length,
2247not including the terminating C<NUL>. If the very first character in the
2248original could not be converted, C<*lenp> will be 0, and the new string will
2249contain just a single C<NUL>. If the entire input string was converted,
2250C<*is_utf8p> is set to FALSE and C<*first_non_downgradable> is set to C<NULL>.
2251
2252Upon successful return, the number of variants in the converted portion of the
2253string can be computed by having saved the value of C<*lenp> before the call,
2254and subtracting the after-call value of C<*lenp> from it.
2255
2256=cut
2257
2258
2259*/
2260
2261U8 *
2262Perl_bytes_from_utf8_loc(const U8 *s, STRLEN *lenp, bool *is_utf8p, const U8** first_unconverted)
2263{
2264 U8 *d;
2265 const U8 *original = s;
2266 U8 *converted_start;
2267 const U8 *send = s + *lenp;
f9a63242 2268
976c1b08 2269 PERL_ARGS_ASSERT_BYTES_FROM_UTF8_LOC;
170a1c22 2270
976c1b08
KW
2271 if (! *is_utf8p) {
2272 if (first_unconverted) {
2273 *first_unconverted = NULL;
2274 }
2275
2276 return (U8 *) original;
2277 }
2278
2279 Newx(d, (*lenp) + 1, U8);
2280
2281 converted_start = d;
7299a045
KW
2282 while (s < send) {
2283 U8 c = *s++;
2284 if (! UTF8_IS_INVARIANT(c)) {
976c1b08
KW
2285
2286 /* Then it is multi-byte encoded. If the code point is above 0xFF,
2287 * have to stop now */
2288 if (UNLIKELY (! UTF8_IS_NEXT_CHAR_DOWNGRADEABLE(s - 1, send))) {
2289 if (first_unconverted) {
2290 *first_unconverted = s - 1;
2291 goto finish_and_return;
2292 }
2293 else {
2294 Safefree(converted_start);
2295 return (U8 *) original;
2296 }
2297 }
2298
7299a045
KW
2299 c = EIGHT_BIT_UTF8_TO_NATIVE(c, *s);
2300 s++;
38af28cf 2301 }
7299a045
KW
2302 *d++ = c;
2303 }
170a1c22 2304
976c1b08
KW
2305 /* Here, converted the whole of the input */
2306 *is_utf8p = FALSE;
2307 if (first_unconverted) {
2308 *first_unconverted = NULL;
170a1c22 2309 }
976c1b08
KW
2310
2311 finish_and_return:
46a08a6f
KW
2312 *d = '\0';
2313 *lenp = d - converted_start;
976c1b08
KW
2314
2315 /* Trim unused space */
2316 Renew(converted_start, *lenp + 1, U8);
2317
2318 return converted_start;
f9a63242
JH
2319}
2320
2321/*
87cea99e 2322=for apidoc bytes_to_utf8
6940069f 2323
09af0336 2324Converts a string C<s> of length C<*lenp> bytes from the native encoding into
ff97e5cf 2325UTF-8.
09af0336 2326Returns a pointer to the newly-created string, and sets C<*lenp> to
ff97e5cf 2327reflect the new length in bytes.
6940069f 2328
3bc0c78c 2329Upon successful return, the number of variants in the string can be computed by
23b37b12 2330having saved the value of C<*lenp> before the call, and subtracting it from the
3bc0c78c
KW
2331after-call value of C<*lenp>.
2332
75200dff 2333A C<NUL> character will be written after the end of the string.
2bbc8d55
SP
2334
2335If you want to convert to UTF-8 from encodings other than
2336the native (Latin1 or EBCDIC),
a1433954 2337see L</sv_recode_to_utf8>().
c9ada85f 2338
497711e7 2339=cut
6940069f
GS
2340*/
2341
2342U8*
09af0336 2343Perl_bytes_to_utf8(pTHX_ const U8 *s, STRLEN *lenp)
6940069f 2344{
09af0336 2345 const U8 * const send = s + (*lenp);
6940069f
GS
2346 U8 *d;
2347 U8 *dst;
7918f24d
NC
2348
2349 PERL_ARGS_ASSERT_BYTES_TO_UTF8;
96a5add6 2350 PERL_UNUSED_CONTEXT;
6940069f 2351
09af0336 2352 Newx(d, (*lenp) * 2 + 1, U8);
6940069f
GS
2353 dst = d;
2354
2355 while (s < send) {
55d09dc8
KW
2356 append_utf8_from_native_byte(*s, &d);
2357 s++;
6940069f 2358 }
2e11cf67 2359
6940069f 2360 *d = '\0';
09af0336 2361 *lenp = d-dst;
2e11cf67
KW
2362
2363 /* Trim unused space */
2364 Renew(dst, *lenp + 1, U8);
2365
6940069f
GS
2366 return dst;
2367}
2368
a0ed51b3 2369/*
624504c5
KW
2370 * Convert native (big-endian) UTF-16 to UTF-8. For reversed (little-endian),
2371 * use utf16_to_utf8_reversed().
a0ed51b3 2372 *
624504c5
KW
2373 * UTF-16 requires 2 bytes for every code point below 0x10000; otherwise 4 bytes.
2374 * UTF-8 requires 1-3 bytes for every code point below 0x1000; otherwise 4 bytes.
2375 * UTF-EBCDIC requires 1-4 bytes for every code point below 0x1000; otherwise 4-5 bytes.
2376 *
2377 * These functions don't check for overflow. The worst case is every code
2378 * point in the input is 2 bytes, and requires 4 bytes on output. (If the code
2379 * is never going to run in EBCDIC, it is 2 bytes requiring 3 on output.) Therefore the
2380 * destination must be pre-extended to 2 times the source length.
2381 *
2382 * Do not use in-place. We optimize for native, for obvious reasons. */
a0ed51b3
LW
2383
2384U8*
dea0fc0b 2385Perl_utf16_to_utf8(pTHX_ U8* p, U8* d, I32 bytelen, I32 *newlen)
a0ed51b3 2386{
dea0fc0b
JH
2387 U8* pend;
2388 U8* dstart = d;
2389
7918f24d
NC
2390 PERL_ARGS_ASSERT_UTF16_TO_UTF8;
2391
dea0fc0b 2392 if (bytelen & 1)
56576a04
KW
2393 Perl_croak(aTHX_ "panic: utf16_to_utf8: odd bytelen %" UVuf,
2394 (UV)bytelen);
dea0fc0b
JH
2395
2396 pend = p + bytelen;
2397
a0ed51b3 2398 while (p < pend) {
dea0fc0b
JH
2399 UV uv = (p[0] << 8) + p[1]; /* UTF-16BE */
2400 p += 2;
2d1545e5 2401 if (OFFUNI_IS_INVARIANT(uv)) {
56d37426 2402 *d++ = LATIN1_TO_NATIVE((U8) uv);
a0ed51b3
LW
2403 continue;
2404 }
56d37426
KW
2405 if (uv <= MAX_UTF8_TWO_BYTE) {
2406 *d++ = UTF8_TWO_BYTE_HI(UNI_TO_NATIVE(uv));
2407 *d++ = UTF8_TWO_BYTE_LO(UNI_TO_NATIVE(uv));
a0ed51b3
LW
2408 continue;
2409 }
ffd0a9d3 2410
46956fad
KW
2411#define FIRST_HIGH_SURROGATE UNICODE_SURROGATE_FIRST
2412#define LAST_HIGH_SURROGATE 0xDBFF
2413#define FIRST_LOW_SURROGATE 0xDC00
2414#define LAST_LOW_SURROGATE UNICODE_SURROGATE_LAST
ffd0a9d3 2415#define FIRST_IN_PLANE1 0x10000
e23c50db
KW
2416
2417 /* This assumes that most uses will be in the first Unicode plane, not
2418 * needing surrogates */
2419 if (UNLIKELY(uv >= UNICODE_SURROGATE_FIRST
2420 && uv <= UNICODE_SURROGATE_LAST))
2421 {
2422 if (UNLIKELY(p >= pend) || UNLIKELY(uv > LAST_HIGH_SURROGATE)) {
2423 Perl_croak(aTHX_ "Malformed UTF-16 surrogate");
2424 }
2425 else {
01ea242b 2426 UV low = (p[0] << 8) + p[1];
e23c50db
KW
2427 if ( UNLIKELY(low < FIRST_LOW_SURROGATE)
2428 || UNLIKELY(low > LAST_LOW_SURROGATE))
2429 {
01ea242b 2430 Perl_croak(aTHX_ "Malformed UTF-16 surrogate");
e23c50db
KW
2431 }
2432 p += 2;
46956fad 2433 uv = ((uv - FIRST_HIGH_SURROGATE) << 10)
ffd0a9d3 2434 + (low - FIRST_LOW_SURROGATE) + FIRST_IN_PLANE1;
01ea242b 2435 }
a0ed51b3 2436 }
56d37426
KW
2437#ifdef EBCDIC
2438 d = uvoffuni_to_utf8_flags(d, uv, 0);
2439#else
ffd0a9d3 2440 if (uv < FIRST_IN_PLANE1) {
eb160463
GS
2441 *d++ = (U8)(( uv >> 12) | 0xe0);
2442 *d++ = (U8)(((uv >> 6) & 0x3f) | 0x80);
2443 *d++ = (U8)(( uv & 0x3f) | 0x80);
a0ed51b3
LW
2444 continue;
2445 }
2446 else {
eb160463
GS
2447 *d++ = (U8)(( uv >> 18) | 0xf0);
2448 *d++ = (U8)(((uv >> 12) & 0x3f) | 0x80);
2449 *d++ = (U8)(((uv >> 6) & 0x3f) | 0x80);
2450 *d++ = (U8)(( uv & 0x3f) | 0x80);
a0ed51b3
LW
2451 continue;
2452 }
56d37426 2453#endif
a0ed51b3 2454 }
dea0fc0b 2455 *newlen = d - dstart;
a0ed51b3
LW
2456 return d;
2457}
2458
2459/* Note: this one is slightly destructive of the source. */
2460
2461U8*
dea0fc0b 2462Perl_utf16_to_utf8_reversed(pTHX_ U8* p, U8* d, I32 bytelen, I32 *newlen)
a0ed51b3
LW
2463{
2464 U8* s = (U8*)p;
d4c19fe8 2465 U8* const send = s + bytelen;
7918f24d
NC
2466
2467 PERL_ARGS_ASSERT_UTF16_TO_UTF8_REVERSED;
2468
e0ea5e2d 2469 if (bytelen & 1)
147e3846 2470 Perl_croak(aTHX_ "panic: utf16_to_utf8_reversed: odd bytelen %" UVuf,
e0ea5e2d
NC
2471 (UV)bytelen);
2472
a0ed51b3 2473 while (s < send) {
d4c19fe8 2474 const U8 tmp = s[0];
a0ed51b3
LW
2475 s[0] = s[1];
2476 s[1] = tmp;
2477 s += 2;
2478 }
dea0fc0b 2479 return utf16_to_utf8(p, d, bytelen, newlen);
a0ed51b3
LW
2480}
2481
922e8cb4
KW
2482bool
2483Perl__is_uni_FOO(pTHX_ const U8 classnum, const UV c)
2484{
2485 U8 tmpbuf[UTF8_MAXBYTES+1];
2486 uvchr_to_utf8(tmpbuf, c);
da8c1a98 2487 return _is_utf8_FOO_with_len(classnum, tmpbuf, tmpbuf + sizeof(tmpbuf));
922e8cb4
KW
2488}
2489
f9ae8fb6
JD
2490/* Internal function so we can deprecate the external one, and call
2491 this one from other deprecated functions in this file */
2492
f2645549
KW
2493bool
2494Perl__is_utf8_idstart(pTHX_ const U8 *p)
61b19385 2495{
f2645549 2496 PERL_ARGS_ASSERT__IS_UTF8_IDSTART;
61b19385
KW
2497
2498 if (*p == '_')
2499 return TRUE;
f25ce844 2500 return is_utf8_common(p, &PL_utf8_idstart, "IdStart", NULL);
61b19385
KW
2501}
2502
5092f92a 2503bool
eba68aa0
KW
2504Perl__is_uni_perl_idcont(pTHX_ UV c)
2505{
2506 U8 tmpbuf[UTF8_MAXBYTES+1];
2507 uvchr_to_utf8(tmpbuf, c);
da8c1a98 2508 return _is_utf8_perl_idcont_with_len(tmpbuf, tmpbuf + sizeof(tmpbuf));
eba68aa0
KW
2509}
2510
2511bool
f91dcd13
KW
2512Perl__is_uni_perl_idstart(pTHX_ UV c)
2513{
2514 U8 tmpbuf[UTF8_MAXBYTES+1];
2515 uvchr_to_utf8(tmpbuf, c);
da8c1a98 2516 return _is_utf8_perl_idstart_with_len(tmpbuf, tmpbuf + sizeof(tmpbuf));
f91dcd13
KW
2517}
2518
3a4c58c9 2519UV
56576a04
KW
2520Perl__to_upper_title_latin1(pTHX_ const U8 c, U8* p, STRLEN *lenp,
2521 const char S_or_s)
3a4c58c9
KW
2522{
2523 /* We have the latin1-range values compiled into the core, so just use
4a4088c4 2524 * those, converting the result to UTF-8. The only difference between upper
3a4c58c9
KW
2525 * and title case in this range is that LATIN_SMALL_LETTER_SHARP_S is
2526 * either "SS" or "Ss". Which one to use is passed into the routine in
2527 * 'S_or_s' to avoid a test */
2528
2529 UV converted = toUPPER_LATIN1_MOD(c);
2530
2531 PERL_ARGS_ASSERT__TO_UPPER_TITLE_LATIN1;
2532
2533 assert(S_or_s == 'S' || S_or_s == 's');
2534
6f2d5cbc 2535 if (UVCHR_IS_INVARIANT(converted)) { /* No difference between the two for
f4cd282c 2536 characters in this range */
3a4c58c9
KW
2537 *p = (U8) converted;
2538 *lenp = 1;
2539 return converted;
2540 }
2541
2542 /* toUPPER_LATIN1_MOD gives the correct results except for three outliers,
2543 * which it maps to one of them, so as to only have to have one check for
2544 * it in the main case */
2545 if (UNLIKELY(converted == LATIN_SMALL_LETTER_Y_WITH_DIAERESIS)) {
2546 switch (c) {
2547 case LATIN_SMALL_LETTER_Y_WITH_DIAERESIS:
2548 converted = LATIN_CAPITAL_LETTER_Y_WITH_DIAERESIS;
2549 break;
2550 case MICRO_SIGN:
2551 converted = GREEK_CAPITAL_LETTER_MU;
2552 break;
79e064b9
KW
2553#if UNICODE_MAJOR_VERSION > 2 \
2554 || (UNICODE_MAJOR_VERSION == 2 && UNICODE_DOT_VERSION >= 1 \
2555 && UNICODE_DOT_DOT_VERSION >= 8)
3a4c58c9
KW
2556 case LATIN_SMALL_LETTER_SHARP_S:
2557 *(p)++ = 'S';
2558 *p = S_or_s;
2559 *lenp = 2;
2560 return 'S';
79e064b9 2561#endif
3a4c58c9 2562 default:
56576a04
KW
2563 Perl_croak(aTHX_ "panic: to_upper_title_latin1 did not expect"
2564 " '%c' to map to '%c'",
2565 c, LATIN_SMALL_LETTER_Y_WITH_DIAERESIS);
e5964223 2566 NOT_REACHED; /* NOTREACHED */
3a4c58c9
KW
2567 }
2568 }
2569
2570 *(p)++ = UTF8_TWO_BYTE_HI(converted);
2571 *p = UTF8_TWO_BYTE_LO(converted);
2572 *lenp = 2;
2573
2574 return converted;
2575}
2576
50bda2c3
KW
2577/* Call the function to convert a UTF-8 encoded character to the specified case.
2578 * Note that there may be more than one character in the result.
2579 * INP is a pointer to the first byte of the input character
2580 * OUTP will be set to the first byte of the string of changed characters. It
2581 * needs to have space for UTF8_MAXBYTES_CASE+1 bytes
2582 * LENP will be set to the length in bytes of the string of changed characters
2583 *
56576a04
KW
2584 * The functions return the ordinal of the first character in the string of
2585 * OUTP */
2586#define CALL_UPPER_CASE(uv, s, d, lenp) \
2587 _to_utf8_case(uv, s, d, lenp, &PL_utf8_toupper, "ToUc", "")
2588#define CALL_TITLE_CASE(uv, s, d, lenp) \
2589 _to_utf8_case(uv, s, d, lenp, &PL_utf8_totitle, "ToTc", "")
2590#define CALL_LOWER_CASE(uv, s, d, lenp) \
2591 _to_utf8_case(uv, s, d, lenp, &PL_utf8_tolower, "ToLc", "")
50bda2c3 2592
b9992569
KW
2593/* This additionally has the input parameter 'specials', which if non-zero will
2594 * cause this to use the specials hash for folding (meaning get full case
50bda2c3 2595 * folding); otherwise, when zero, this implies a simple case fold */
56576a04
KW
2596#define CALL_FOLD_CASE(uv, s, d, lenp, specials) \
2597_to_utf8_case(uv, s, d, lenp, &PL_utf8_tofold, "ToCf", (specials) ? "" : NULL)
c3fd2246 2598
84afefe6
JH
2599UV
2600Perl_to_uni_upper(pTHX_ UV c, U8* p, STRLEN *lenp)
a0ed51b3 2601{
a1433954
KW
2602 /* Convert the Unicode character whose ordinal is <c> to its uppercase
2603 * version and store that in UTF-8 in <p> and its length in bytes in <lenp>.
2604 * Note that the <p> needs to be at least UTF8_MAXBYTES_CASE+1 bytes since
c3fd2246
KW
2605 * the changed version may be longer than the original character.
2606 *
2607 * The ordinal of the first character of the changed version is returned
2608 * (but note, as explained above, that there may be more.) */
2609
7918f24d
NC
2610 PERL_ARGS_ASSERT_TO_UNI_UPPER;
2611
3a4c58c9
KW
2612 if (c < 256) {
2613 return _to_upper_title_latin1((U8) c, p, lenp, 'S');
2614 }
2615
0ebc6274 2616 uvchr_to_utf8(p, c);
b9992569 2617 return CALL_UPPER_CASE(c, p, p, lenp);
a0ed51b3
LW
2618}
2619
84afefe6
JH
2620UV
2621Perl_to_uni_title(pTHX_ UV c, U8* p, STRLEN *lenp)
a0ed51b3 2622{
7918f24d
NC
2623 PERL_ARGS_ASSERT_TO_UNI_TITLE;
2624
3a4c58c9
KW
2625 if (c < 256) {
2626 return _to_upper_title_latin1((U8) c, p, lenp, 's');
2627 }
2628
0ebc6274 2629 uvchr_to_utf8(p, c);
b9992569 2630 return CALL_TITLE_CASE(c, p, p, lenp);
a0ed51b3
LW
2631}
2632
afc16117 2633STATIC U8
eaf412bf 2634S_to_lower_latin1(const U8 c, U8* p, STRLEN *lenp, const char dummy)
afc16117
KW
2635{
2636 /* We have the latin1-range values compiled into the core, so just use
4a4088c4 2637 * those, converting the result to UTF-8. Since the result is always just
a1433954 2638 * one character, we allow <p> to be NULL */
afc16117
KW
2639
2640 U8 converted = toLOWER_LATIN1(c);
2641
eaf412bf
KW
2642 PERL_UNUSED_ARG(dummy);
2643
afc16117 2644 if (p != NULL) {
6f2d5cbc 2645 if (NATIVE_BYTE_IS_INVARIANT(converted)) {
afc16117
KW
2646 *p = converted;
2647 *lenp = 1;
2648 }
2649 else {
430c9760
KW
2650 /* Result is known to always be < 256, so can use the EIGHT_BIT
2651 * macros */
2652 *p = UTF8_EIGHT_BIT_HI(converted);
2653 *(p+1) = UTF8_EIGHT_BIT_LO(converted);
afc16117
KW
2654 *lenp = 2;
2655 }
2656 }
2657 return converted;
2658}
2659
84afefe6
JH
2660UV
2661Perl_to_uni_lower(pTHX_ UV c, U8* p, STRLEN *lenp)
a0ed51b3 2662{
7918f24d
NC
2663 PERL_ARGS_ASSERT_TO_UNI_LOWER;
2664
afc16117 2665 if (c < 256) {
eaf412bf 2666 return to_lower_latin1((U8) c, p, lenp, 0 /* 0 is a dummy arg */ );
bca00c02
KW
2667 }
2668
afc16117 2669 uvchr_to_utf8(p, c);
b9992569 2670 return CALL_LOWER_CASE(c, p, p, lenp);
a0ed51b3
LW
2671}
2672
84afefe6 2673UV
56576a04
KW
2674Perl__to_fold_latin1(pTHX_ const U8 c, U8* p, STRLEN *lenp,
2675 const unsigned int flags)
a1dde8de 2676{
51910141 2677 /* Corresponds to to_lower_latin1(); <flags> bits meanings:
1ca267a5 2678 * FOLD_FLAGS_NOMIX_ASCII iff non-ASCII to ASCII folds are prohibited
51910141 2679 * FOLD_FLAGS_FULL iff full folding is to be used;
1ca267a5
KW
2680 *
2681 * Not to be used for locale folds
51910141 2682 */
f673fad4 2683
a1dde8de
KW
2684 UV converted;
2685
2686 PERL_ARGS_ASSERT__TO_FOLD_LATIN1;
81611534 2687 PERL_UNUSED_CONTEXT;
a1dde8de 2688
1ca267a5
KW
2689 assert (! (flags & FOLD_FLAGS_LOCALE));
2690
659a7c2d 2691 if (UNLIKELY(c == MICRO_SIGN)) {
a1dde8de
KW
2692 converted = GREEK_SMALL_LETTER_MU;
2693 }
9b63e895
KW
2694#if UNICODE_MAJOR_VERSION > 3 /* no multifolds in early Unicode */ \
2695 || (UNICODE_MAJOR_VERSION == 3 && ( UNICODE_DOT_VERSION > 0) \
2696 || UNICODE_DOT_DOT_VERSION > 0)
659a7c2d
KW
2697 else if ( (flags & FOLD_FLAGS_FULL)
2698 && UNLIKELY(c == LATIN_SMALL_LETTER_SHARP_S))
2699 {
1ca267a5
KW
2700 /* If can't cross 127/128 boundary, can't return "ss"; instead return
2701 * two U+017F characters, as fc("\df") should eq fc("\x{17f}\x{17f}")
2702 * under those circumstances. */
2703 if (flags & FOLD_FLAGS_NOMIX_ASCII) {
2704 *lenp = 2 * sizeof(LATIN_SMALL_LETTER_LONG_S_UTF8) - 2;
2705 Copy(LATIN_SMALL_LETTER_LONG_S_UTF8 LATIN_SMALL_LETTER_LONG_S_UTF8,
2706 p, *lenp, U8);
2707 return LATIN_SMALL_LETTER_LONG_S;
2708 }
2709 else {
4f489194
KW
2710 *(p)++ = 's';
2711 *p = 's';
2712 *lenp = 2;
2713 return 's';
1ca267a5 2714 }
a1dde8de 2715 }
9b63e895 2716#endif
a1dde8de
KW
2717 else { /* In this range the fold of all other characters is their lower
2718 case */
2719 converted = toLOWER_LATIN1(c);
2720 }
2721
6f2d5cbc 2722 if (UVCHR_IS_INVARIANT(converted)) {
a1dde8de
KW
2723 *p = (U8) converted;
2724 *lenp = 1;
2725 }
2726 else {
2727 *(p)++ = UTF8_TWO_BYTE_HI(converted);
2728 *p = UTF8_TWO_BYTE_LO(converted);
2729 *lenp = 2;
2730 }
2731
2732 return converted;
2733}
2734
2735UV
31f05a37 2736Perl__to_uni_fold_flags(pTHX_ UV c, U8* p, STRLEN *lenp, U8 flags)
84afefe6 2737{
4b593389 2738
a0270393
KW
2739 /* Not currently externally documented, and subject to change
2740 * <flags> bits meanings:
2741 * FOLD_FLAGS_FULL iff full folding is to be used;
31f05a37
KW
2742 * FOLD_FLAGS_LOCALE is set iff the rules from the current underlying
2743 * locale are to be used.
a0270393
KW
2744 * FOLD_FLAGS_NOMIX_ASCII iff non-ASCII to ASCII folds are prohibited
2745 */
4b593389 2746
36bb2ab6 2747 PERL_ARGS_ASSERT__TO_UNI_FOLD_FLAGS;
7918f24d 2748
780fcc9f
KW
2749 if (flags & FOLD_FLAGS_LOCALE) {
2750 /* Treat a UTF-8 locale as not being in locale at all */
2751 if (IN_UTF8_CTYPE_LOCALE) {
2752 flags &= ~FOLD_FLAGS_LOCALE;
2753 }
2754 else {
2755 _CHECK_AND_WARN_PROBLEMATIC_LOCALE;
e7b7ac46 2756 goto needs_full_generality;
780fcc9f 2757 }
31f05a37
KW
2758 }
2759
a1dde8de 2760 if (c < 256) {
e7b7ac46 2761 return _to_fold_latin1((U8) c, p, lenp,
31f05a37 2762 flags & (FOLD_FLAGS_FULL | FOLD_FLAGS_NOMIX_ASCII));
a1dde8de
KW
2763 }
2764
2f306ab9 2765 /* Here, above 255. If no special needs, just use the macro */
a0270393
KW
2766 if ( ! (flags & (FOLD_FLAGS_LOCALE|FOLD_FLAGS_NOMIX_ASCII))) {
2767 uvchr_to_utf8(p, c);
b9992569 2768 return CALL_FOLD_CASE(c, p, p, lenp, flags & FOLD_FLAGS_FULL);
a0270393 2769 }
567b353c 2770 else { /* Otherwise, _toFOLD_utf8_flags has the intelligence to deal with
a0270393
KW
2771 the special flags. */
2772 U8 utf8_c[UTF8_MAXBYTES + 1];
e7b7ac46
KW
2773
2774 needs_full_generality:
a0270393 2775 uvchr_to_utf8(utf8_c, c);
56576a04
KW
2776 return _toFOLD_utf8_flags(utf8_c, utf8_c + sizeof(utf8_c),
2777 p, lenp, flags);
a0270393 2778 }
84afefe6
JH
2779}
2780
26483009 2781PERL_STATIC_INLINE bool
5141f98e 2782S_is_utf8_common(pTHX_ const U8 *const p, SV **swash,
f25ce844 2783 const char *const swashname, SV* const invlist)
bde6a22d 2784{
ea317ccb
KW
2785 /* returns a boolean giving whether or not the UTF8-encoded character that
2786 * starts at <p> is in the swash indicated by <swashname>. <swash>
2787 * contains a pointer to where the swash indicated by <swashname>
2788 * is to be stored; which this routine will do, so that future calls will
f25ce844
KW
2789 * look at <*swash> and only generate a swash if it is not null. <invlist>
2790 * is NULL or an inversion list that defines the swash. If not null, it
2791 * saves time during initialization of the swash.
ea317ccb
KW
2792 *
2793 * Note that it is assumed that the buffer length of <p> is enough to
2794 * contain all the bytes that comprise the character. Thus, <*p> should
2795 * have been checked before this call for mal-formedness enough to assure
2796 * that. */
2797
7918f24d
NC
2798 PERL_ARGS_ASSERT_IS_UTF8_COMMON;
2799
492a624f 2800 /* The API should have included a length for the UTF-8 character in <p>,
28123549 2801 * but it doesn't. We therefore assume that p has been validated at least
492a624f
KW
2802 * as far as there being enough bytes available in it to accommodate the
2803 * character without reading beyond the end, and pass that number on to the
2804 * validating routine */
6302f837 2805 if (! isUTF8_CHAR(p, p + UTF8SKIP(p))) {
86ae6e94 2806 _force_out_malformed_utf8_message(p, p + UTF8SKIP(p),
99a765e9 2807 _UTF8_NO_CONFIDENCE_IN_CURLEN,
86ae6e94
KW
2808 1 /* Die */ );
2809 NOT_REACHED; /* NOTREACHED */
28123549 2810 }
86ae6e94 2811
87367d5f
KW
2812 if (!*swash) {
2813 U8 flags = _CORE_SWASH_INIT_ACCEPT_INVLIST;
f25ce844
KW
2814 *swash = _core_swash_init("utf8",
2815
2816 /* Only use the name if there is no inversion
2817 * list; otherwise will go out to disk */
2818 (invlist) ? "" : swashname,
2819
2820 &PL_sv_undef, 1, 0, invlist, &flags);
87367d5f 2821 }
28123549 2822
bde6a22d
NC
2823 return swash_fetch(*swash, p, TRUE) != 0;
2824}
2825
da8c1a98 2826PERL_STATIC_INLINE bool
56576a04
KW
2827S_is_utf8_common_with_len(pTHX_ const U8 *const p, const U8 * const e,
2828 SV **swash, const char *const swashname,
2829 SV* const invlist)
da8c1a98
KW
2830{
2831 /* returns a boolean giving whether or not the UTF8-encoded character that
2832 * starts at <p>, and extending no further than <e - 1> is in the swash
2833 * indicated by <swashname>. <swash> contains a pointer to where the swash
2834 * indicated by <swashname> is to be stored; which this routine will do, so
2835 * that future calls will look at <*swash> and only generate a swash if it
2836 * is not null. <invlist> is NULL or an inversion list that defines the
2837 * swash. If not null, it saves time during initialization of the swash.
2838 */
2839
2840 PERL_ARGS_ASSERT_IS_UTF8_COMMON_WITH_LEN;
2841
2842 if (! isUTF8_CHAR(p, e)) {
2843 _force_out_malformed_utf8_message(p, e, 0, 1);
2844 NOT_REACHED; /* NOTREACHED */
2845 }
2846
2847 if (!*swash) {
2848 U8 flags = _CORE_SWASH_INIT_ACCEPT_INVLIST;
2849 *swash = _core_swash_init("utf8",
2850
2851 /* Only use the name if there is no inversion
2852 * list; otherwise will go out to disk */
2853 (invlist) ? "" : swashname,
2854
2855 &PL_sv_undef, 1, 0, invlist, &flags);
2856 }
2857
2858 return swash_fetch(*swash, p, TRUE) != 0;
2859}
2860
34aeb2e9
KW
2861STATIC void
2862S_warn_on_first_deprecated_use(pTHX_ const char * const name,
2863 const char * const alternative,
2864 const bool use_locale,
2865 const char * const file,
2866 const unsigned line)
2867{
2868 const char * key;
2869
2870 PERL_ARGS_ASSERT_WARN_ON_FIRST_DEPRECATED_USE;
2871
2872 if (ckWARN_d(WARN_DEPRECATED)) {
2873
2874 key = Perl_form(aTHX_ "%s;%d;%s;%d", name, use_locale, file, line);
2875 if (! hv_fetch(PL_seen_deprecated_macro, key, strlen(key), 0)) {
2876 if (! PL_seen_deprecated_macro) {
2877 PL_seen_deprecated_macro = newHV();
2878 }
2879 if (! hv_store(PL_seen_deprecated_macro, key,
2880 strlen(key), &PL_sv_undef, 0))
2881 {
2882 Perl_croak(aTHX_ "panic: hv_store() unexpectedly failed");
2883 }
2884
c44e9413 2885 if (instr(file, "mathoms.c")) {
607313a1
KW
2886 Perl_warner(aTHX_ WARN_DEPRECATED,
2887 "In %s, line %d, starting in Perl v5.30, %s()"
2888 " will be removed. Avoid this message by"
2889 " converting to use %s().\n",
2890 file, line, name, alternative);
2891 }
2892 else {
34aeb2e9
KW
2893 Perl_warner(aTHX_ WARN_DEPRECATED,
2894 "In %s, line %d, starting in Perl v5.30, %s() will"
2895 " require an additional parameter. Avoid this"
2896 " message by converting to use %s().\n",
2897 file, line, name, alternative);
607313a1 2898 }
34aeb2e9
KW
2899 }
2900 }
2901}
2902
bde6a22d 2903bool
34aeb2e9 2904Perl__is_utf8_FOO(pTHX_ U8 classnum,
be99e2c2 2905 const U8 * const p,
34aeb2e9
KW
2906 const char * const name,
2907 const char * const alternative,
2908 const bool use_utf8,
2909 const bool use_locale,
2910 const char * const file,
2911 const unsigned line)
922e8cb4 2912{
922e8cb4
KW
2913 PERL_ARGS_ASSERT__IS_UTF8_FOO;
2914
34aeb2e9
KW
2915 warn_on_first_deprecated_use(name, alternative, use_locale, file, line);
2916
2917 if (use_utf8 && UTF8_IS_ABOVE_LATIN1(*p)) {
34aeb2e9
KW
2918
2919 switch (classnum) {
2920 case _CC_WORDCHAR:
2921 case _CC_DIGIT:
2922 case _CC_ALPHA:
2923 case _CC_LOWER:
2924 case _CC_UPPER:
2925 case _CC_PUNCT:
2926 case _CC_PRINT:
2927 case _CC_ALPHANUMERIC:
2928 case _CC_GRAPH:
2929 case _CC_CASED:
2930
2931 return is_utf8_common(p,
2932 &PL_utf8_swash_ptrs[classnum],
2933 swash_property_names[classnum],
2934 PL_XPosix_ptrs[classnum]);
2935
2936 case _CC_SPACE:
2937 return is_XPERLSPACE_high(p);
2938 case _CC_BLANK:
2939 return is_HORIZWS_high(p);
2940 case _CC_XDIGIT:
2941 return is_XDIGIT_high(p);
2942 case _CC_CNTRL:
2943 return 0;
2944 case _CC_ASCII:
2945 return 0;
2946 case _CC_VERTSPACE:
2947 return is_VERTWS_high(p);
2948 case _CC_IDFIRST:
2949 if (! PL_utf8_perl_idstart) {
22f0498f
KW
2950 PL_utf8_perl_idstart
2951 = _new_invlist_C_array(_Perl_IDStart_invlist);
34aeb2e9 2952 }
22f0498f
KW
2953 return is_utf8_common(p, &PL_utf8_perl_idstart,
2954 "_Perl_IDStart", NULL);
34aeb2e9
KW
2955 case _CC_IDCONT:
2956 if (! PL_utf8_perl_idcont) {
22f0498f
KW
2957 PL_utf8_perl_idcont
2958 = _new_invlist_C_array(_Perl_IDCont_invlist);
34aeb2e9 2959 }
22f0498f
KW
2960 return is_utf8_common(p, &PL_utf8_perl_idcont,
2961 "_Perl_IDCont", NULL);
34aeb2e9
KW
2962 }
2963 }
2964
2965 /* idcont is the same as wordchar below 256 */
2966 if (classnum == _CC_IDCONT) {
2967 classnum = _CC_WORDCHAR;
2968 }
2969 else if (classnum == _CC_IDFIRST) {
2970 if (*p == '_') {
2971 return TRUE;
2972 }
2973 classnum = _CC_ALPHA;
2974 }
2975
2976 if (! use_locale) {
2977 if (! use_utf8 || UTF8_IS_INVARIANT(*p)) {
2978 return _generic_isCC(*p, classnum);
2979 }
922e8cb4 2980
34aeb2e9
KW
2981 return _generic_isCC(EIGHT_BIT_UTF8_TO_NATIVE(*p, *(p + 1 )), classnum);
2982 }
2983 else {
2984 if (! use_utf8 || UTF8_IS_INVARIANT(*p)) {
2985 return isFOO_lc(classnum, *p);
2986 }
2987
2988 return isFOO_lc(classnum, EIGHT_BIT_UTF8_TO_NATIVE(*p, *(p + 1 )));
2989 }
2990
2991 NOT_REACHED; /* NOTREACHED */
922e8cb4
KW
2992}
2993
2994bool
da8c1a98
KW
2995Perl__is_utf8_FOO_with_len(pTHX_ const U8 classnum, const U8 *p,
2996 const U8 * const e)
2997{
2998 PERL_ARGS_ASSERT__IS_UTF8_FOO_WITH_LEN;
2999
3000 assert(classnum < _FIRST_NON_SWASH_CC);
3001
3002 return is_utf8_common_with_len(p,
3003 e,
3004 &PL_utf8_swash_ptrs[classnum],
3005 swash_property_names[classnum],
3006 PL_XPosix_ptrs[classnum]);
3007}
3008
3009bool
da8c1a98
KW
3010Perl__is_utf8_perl_idstart_with_len(pTHX_ const U8 *p, const U8 * const e)
3011{
3012 SV* invlist = NULL;
3013
3014 PERL_ARGS_ASSERT__IS_UTF8_PERL_IDSTART_WITH_LEN;
3015
3016 if (! PL_utf8_perl_idstart) {
3017 invlist = _new_invlist_C_array(_Perl_IDStart_invlist);
3018 }
3019 return is_utf8_common_with_len(p, e, &PL_utf8_perl_idstart,
3020 "_Perl_IDStart", invlist);
3021}
3022
3023bool
f2645549 3024Perl__is_utf8_xidstart(pTHX_ const U8 *p)
c11ff943 3025{
f2645549 3026 PERL_ARGS_ASSERT__IS_UTF8_XIDSTART;
c11ff943
KW
3027
3028 if (*p == '_')
3029 return TRUE;
f25ce844 3030 return is_utf8_common(p, &PL_utf8_xidstart, "XIdStart", NULL);
c11ff943
KW
3031}
3032
3033bool
da8c1a98
KW
3034Perl__is_utf8_perl_idcont_with_len(pTHX_ const U8 *p, const U8 * const e)
3035{
3036 SV* invlist = NULL;
3037
3038 PERL_ARGS_ASSERT__IS_UTF8_PERL_IDCONT_WITH_LEN;
3039
3040 if (! PL_utf8_perl_idcont) {
3041 invlist = _new_invlist_C_array(_Perl_IDCont_invlist);
3042 }
3043 return is_utf8_common_with_len(p, e, &PL_utf8_perl_idcont,
3044 "_Perl_IDCont", invlist);
3045}
3046
3047bool
f2645549 3048Perl__is_utf8_idcont(pTHX_ const U8 *p)
82686b01 3049{
f2645549 3050 PERL_ARGS_ASSERT__IS_UTF8_IDCONT;
7918f24d 3051
f25ce844 3052 return is_utf8_common(p, &PL_utf8_idcont, "IdContinue", NULL);
a0ed51b3
LW
3053}
3054
3055bool
f2645549 3056Perl__is_utf8_xidcont(pTHX_ const U8 *p)
c11ff943 3057{
f2645549 3058 PERL_ARGS_ASSERT__IS_UTF8_XIDCONT;
c11ff943 3059
f25ce844 3060 return is_utf8_common(p, &PL_utf8_idcont, "XIdContinue", NULL);
c11ff943
KW
3061}
3062
3063bool
7dbf68d2
KW
3064Perl__is_utf8_mark(pTHX_ const U8 *p)
3065{
7dbf68d2
KW
3066 PERL_ARGS_ASSERT__IS_UTF8_MARK;
3067
f25ce844 3068 return is_utf8_common(p, &PL_utf8_mark, "IsM", NULL);
7dbf68d2
KW
3069}
3070
b9992569 3071 /* change namve uv1 to 'from' */
6a4a25f4 3072STATIC UV
b9992569
KW
3073S__to_utf8_case(pTHX_ const UV uv1, const U8 *p, U8* ustrp, STRLEN *lenp,
3074 SV **swashp, const char *normal, const char *special)
3075{
0134edef 3076 STRLEN len = 0;
7918f24d 3077
b9992569 3078 PERL_ARGS_ASSERT__TO_UTF8_CASE;
7918f24d 3079
36eaa811
KW
3080 /* For code points that don't change case, we already know that the output
3081 * of this function is the unchanged input, so we can skip doing look-ups
3082 * for them. Unfortunately the case-changing code points are scattered
3083 * around. But there are some long consecutive ranges where there are no
3084 * case changing code points. By adding tests, we can eliminate the lookup
3085 * for all the ones in such ranges. This is currently done here only for
3086 * just a few cases where the scripts are in common use in modern commerce
3087 * (and scripts adjacent to those which can be included without additional
3088 * tests). */
3089
3090 if (uv1 >= 0x0590) {
3091 /* This keeps from needing further processing the code points most
3092 * likely to be used in the following non-cased scripts: Hebrew,
3093 * Arabic, Syriac, Thaana, NKo, Samaritan, Mandaic, Devanagari,
3094 * Bengali, Gurmukhi, Gujarati, Oriya, Tamil, Telugu, Kannada,
3095 * Malayalam, Sinhala, Thai, Lao, Tibetan, Myanmar */
3096 if (uv1 < 0x10A0) {
3097 goto cases_to_self;
3098 }
3099
3100 /* The following largish code point ranges also don't have case
3101 * changes, but khw didn't think they warranted extra tests to speed
3102 * them up (which would slightly slow down everything else above them):
3103 * 1100..139F Hangul Jamo, Ethiopic
3104 * 1400..1CFF Unified Canadian Aboriginal Syllabics, Ogham, Runic,
3105 * Tagalog, Hanunoo, Buhid, Tagbanwa, Khmer, Mongolian,
3106 * Limbu, Tai Le, New Tai Lue, Buginese, Tai Tham,
3107 * Combining Diacritical Marks Extended, Balinese,
3108 * Sundanese, Batak, Lepcha, Ol Chiki
3109 * 2000..206F General Punctuation
3110 */
3111
3112 if (uv1 >= 0x2D30) {
3113
3114 /* This keeps the from needing further processing the code points
3115 * most likely to be used in the following non-cased major scripts:
3116 * CJK, Katakana, Hiragana, plus some less-likely scripts.
3117 *
3118 * (0x2D30 above might have to be changed to 2F00 in the unlikely
3119 * event that Unicode eventually allocates the unused block as of
3120 * v8.0 2FE0..2FEF to code points that are cased. khw has verified
3121 * that the test suite will start having failures to alert you
3122 * should that happen) */
3123 if (uv1 < 0xA640) {
3124 goto cases_to_self;
3125 }
3126
3127 if (uv1 >= 0xAC00) {
3128 if (UNLIKELY(UNICODE_IS_SURROGATE(uv1))) {
5af9bc97
KW
3129 if (ckWARN_d(WARN_SURROGATE)) {
3130 const char* desc = (PL_op) ? OP_DESC(PL_op) : normal;
3131 Perl_warner(aTHX_ packWARN(WARN_SURROGATE),
56576a04
KW
3132 "Operation \"%s\" returns its argument for"
3133 " UTF-16 surrogate U+%04" UVXf, desc, uv1);
5af9bc97
KW
3134 }
3135 goto cases_to_self;
3136 }
36eaa811
KW
3137
3138 /* AC00..FAFF Catches Hangul syllables and private use, plus
3139 * some others */
3140 if (uv1 < 0xFB00) {
3141 goto cases_to_self;
3142
3143 }
3144
5af9bc97 3145 if (UNLIKELY(UNICODE_IS_SUPER(uv1))) {
d22ec717
KW
3146 if (UNLIKELY(uv1 > MAX_EXTERNALLY_LEGAL_CP)) {
3147 Perl_croak(aTHX_ cp_above_legal_max, uv1,
3148 MAX_EXTERNALLY_LEGAL_CP);
5af9bc97
KW
3149 }
3150 if (ckWARN_d(WARN_NON_UNICODE)) {
3151 const char* desc = (PL_op) ? OP_DESC(PL_op) : normal;
3152 Perl_warner(aTHX_ packWARN(WARN_NON_UNICODE),
56576a04
KW
3153 "Operation \"%s\" returns its argument for"
3154 " non-Unicode code point 0x%04" UVXf, desc, uv1);
5af9bc97
KW
3155 }
3156 goto cases_to_self;
3157 }
3bfc1e70
KW
3158#ifdef HIGHEST_CASE_CHANGING_CP_FOR_USE_ONLY_BY_UTF8_DOT_C
3159 if (UNLIKELY(uv1
3160 > HIGHEST_CASE_CHANGING_CP_FOR_USE_ONLY_BY_UTF8_DOT_C))
3161 {
3162
56576a04
KW
3163 /* As of Unicode 10.0, this means we avoid swash creation
3164 * for anything beyond high Plane 1 (below emojis) */
3bfc1e70
KW
3165 goto cases_to_self;
3166 }
3167#endif
36eaa811
KW
3168 }
3169 }
9ae3ac1a 3170
36eaa811
KW
3171 /* Note that non-characters are perfectly legal, so no warning should
3172 * be given. There are so few of them, that it isn't worth the extra
3173 * tests to avoid swash creation */
9ae3ac1a
KW
3174 }
3175
0134edef 3176 if (!*swashp) /* load on-demand */
56576a04
KW
3177 *swashp = _core_swash_init("utf8", normal, &PL_sv_undef,
3178 4, 0, NULL, NULL);
0134edef 3179
a6f87d8c 3180 if (special) {
0134edef 3181 /* It might be "special" (sometimes, but not always,
2a37f04d 3182 * a multicharacter mapping) */
4a8240a3 3183 HV *hv = NULL;
b08cf34e
JH
3184 SV **svp;
3185
4a8240a3
KW
3186 /* If passed in the specials name, use that; otherwise use any
3187 * given in the swash */
3188 if (*special != '\0') {
3189 hv = get_hv(special, 0);
3190 }
3191 else {
3192 svp = hv_fetchs(MUTABLE_HV(SvRV(*swashp)), "SPECIALS", 0);
3193 if (svp) {
3194 hv = MUTABLE_HV(SvRV(*svp));
3195 }
3196 }
3197
176fe009 3198 if (hv
5f560d8a 3199 && (svp = hv_fetch(hv, (const char*)p, UVCHR_SKIP(uv1), FALSE))
176fe009
KW
3200 && (*svp))
3201 {
cfd0369c 3202 const char *s;
47654450 3203
cfd0369c 3204 s = SvPV_const(*svp, len);
47654450 3205 if (len == 1)
f4cd282c 3206 /* EIGHTBIT */
c80e42f3 3207 len = uvchr_to_utf8(ustrp, *(U8*)s) - ustrp;
2a37f04d 3208 else {
d2dcd0fb 3209 Copy(s, ustrp, len, U8);
29e98929 3210 }
983ffd37 3211 }
0134edef
JH
3212 }
3213
3214 if (!len && *swashp) {
4a4088c4 3215 const UV uv2 = swash_fetch(*swashp, p, TRUE /* => is UTF-8 */);
d4c19fe8 3216
0134edef
JH
3217 if (uv2) {
3218 /* It was "normal" (a single character mapping). */
f4cd282c 3219 len = uvchr_to_utf8(ustrp, uv2) - ustrp;
2a37f04d
JH
3220 }
3221 }
1feea2c7 3222
cbe07460
KW
3223 if (len) {
3224 if (lenp) {
3225 *lenp = len;
3226 }
3227 return valid_utf8_to_uvchr(ustrp, 0);
3228 }
3229
3230 /* Here, there was no mapping defined, which means that the code point maps
3231 * to itself. Return the inputs */
e24dfe9c 3232 cases_to_self:
bfdf22ec 3233 len = UTF8SKIP(p);
ca9fab46
KW
3234 if (p != ustrp) { /* Don't copy onto itself */
3235 Copy(p, ustrp, len, U8);
3236 }
0134edef 3237
2a37f04d
JH
3238 if (lenp)
3239 *lenp = len;
3240
f4cd282c 3241 return uv1;
cbe07460 3242
a0ed51b3
LW
3243}
3244
051a06d4 3245STATIC UV
56576a04
KW
3246S_check_locale_boundary_crossing(pTHX_ const U8* const p, const UV result,
3247 U8* const ustrp, STRLEN *lenp)
051a06d4 3248{
4a4088c4 3249 /* This is called when changing the case of a UTF-8-encoded character above
31f05a37
KW
3250 * the Latin1 range, and the operation is in a non-UTF-8 locale. If the
3251 * result contains a character that crosses the 255/256 boundary, disallow
3252 * the change, and return the original code point. See L<perlfunc/lc> for
3253 * why;
051a06d4 3254 *
a1433954
KW
3255 * p points to the original string whose case was changed; assumed
3256 * by this routine to be well-formed
051a06d4 3257 * result the code point of the first character in the changed-case string
56576a04
KW
3258 * ustrp points to the changed-case string (<result> represents its
3259 * first char)
051a06d4
KW
3260 * lenp points to the length of <ustrp> */
3261
3262 UV original; /* To store the first code point of <p> */
3263
3264 PERL_ARGS_ASSERT_CHECK_LOCALE_BOUNDARY_CROSSING;
3265
a4f12ed7 3266 assert(UTF8_IS_ABOVE_LATIN1(*p));
051a06d4
KW
3267
3268 /* We know immediately if the first character in the string crosses the
3269 * boundary, so can skip */
3270 if (result > 255) {
3271
3272 /* Look at every character in the result; if any cross the
3273 * boundary, the whole thing is disallowed */
3274 U8* s = ustrp + UTF8SKIP(ustrp);
3275 U8* e = ustrp + *lenp;
3276 while (s < e) {
a4f12ed7 3277 if (! UTF8_IS_ABOVE_LATIN1(*s)) {
051a06d4
KW
3278 goto bad_crossing;
3279 }
3280 s += UTF8SKIP(s);
3281 }
3282
613abc6d
KW
3283 /* Here, no characters crossed, result is ok as-is, but we warn. */
3284 _CHECK_AND_OUTPUT_WIDE_LOCALE_UTF8_MSG(p, p + UTF8SKIP(p));
051a06d4
KW
3285 return result;
3286 }
3287
7b52d656 3288 bad_crossing:
051a06d4
KW
3289
3290 /* Failed, have to return the original */
4b88fb76 3291 original = valid_utf8_to_uvchr(p, lenp);
ab0b796c
KW
3292
3293 /* diag_listed_as: Can't do %s("%s") on non-UTF-8 locale; resolved to "%s". */
3294 Perl_ck_warner(aTHX_ packWARN(WARN_LOCALE),
56576a04
KW
3295 "Can't do %s(\"\\x{%" UVXf "}\") on non-UTF-8"
3296 " locale; resolved to \"\\x{%" UVXf "}\".",
357aadde 3297 OP_DESC(PL_op),
ab0b796c
KW
3298 original,
3299 original);
051a06d4
KW
3300 Copy(p, ustrp, *lenp, char);
3301 return original;
3302}
3303
607313a1
KW
3304STATIC U32
3305S_check_and_deprecate(pTHX_ const U8 *p,
3306 const U8 **e,
3307 const unsigned int type, /* See below */
3308 const bool use_locale, /* Is this a 'LC_'
3309 macro call? */
3310 const char * const file,
3311 const unsigned line)
3312{
3313 /* This is a temporary function to deprecate the unsafe calls to the case
3314 * changing macros and functions. It keeps all the special stuff in just
3315 * one place.
3316 *
3317 * It updates *e with the pointer to the end of the input string. If using
3318 * the old-style macros, *e is NULL on input, and so this function assumes
3319 * the input string is long enough to hold the entire UTF-8 sequence, and
3320 * sets *e accordingly, but it then returns a flag to pass the
3321 * utf8n_to_uvchr(), to tell it that this size is a guess, and to avoid
3322 * using the full length if possible.
3323 *
3324 * It also does the assert that *e > p when *e is not NULL. This should be
3325 * migrated to the callers when this function gets deleted.
3326 *
3327 * The 'type' parameter is used for the caller to specify which case
3328 * changing function this is called from: */
3329
3330# define DEPRECATE_TO_UPPER 0
3331# define DEPRECATE_TO_TITLE 1
3332# define DEPRECATE_TO_LOWER 2
3333# define DEPRECATE_TO_FOLD 3
3334
3335 U32 utf8n_flags = 0;
3336 const char * name;
3337 const char * alternative;
3338
3339 PERL_ARGS_ASSERT_CHECK_AND_DEPRECATE;
3340
3341 if (*e == NULL) {
3342 utf8n_flags = _UTF8_NO_CONFIDENCE_IN_CURLEN;
3343 *e = p + UTF8SKIP(p);
3344
3345 /* For mathoms.c calls, we use the function name we know is stored
c44e9413 3346 * there. It could be part of a larger path */
607313a1 3347 if (type == DEPRECATE_TO_UPPER) {
c44e9413 3348 name = instr(file, "mathoms.c")
607313a1
KW
3349 ? "to_utf8_upper"
3350 : "toUPPER_utf8";
3351 alternative = "toUPPER_utf8_safe";
3352 }
3353 else if (type == DEPRECATE_TO_TITLE) {
c44e9413 3354 name = instr(file, "mathoms.c")
607313a1
KW
3355 ? "to_utf8_title"
3356 : "toTITLE_utf8";
3357 alternative = "toTITLE_utf8_safe";
3358 }
3359 else if (type == DEPRECATE_TO_LOWER) {
c44e9413 3360 name = instr(file, "mathoms.c")
607313a1
KW
3361 ? "to_utf8_lower"
3362 : "toLOWER_utf8";
3363 alternative = "toLOWER_utf8_safe";
3364 }
3365 else if (type == DEPRECATE_TO_FOLD) {
c44e9413 3366 name = instr(file, "mathoms.c")
607313a1
KW
3367 ? "to_utf8_fold"
3368 : "toFOLD_utf8";
3369 alternative = "toFOLD_utf8_safe";
3370 }
3371 else Perl_croak(aTHX_ "panic: Unexpected case change type");
3372
3373 warn_on_first_deprecated_use(name, alternative, use_locale, file, line);
3374 }
3375 else {
3376 assert (p < *e);
3377 }
3378
3379 return utf8n_flags;
3380}
3381
eaf412bf
KW
3382/* The process for changing the case is essentially the same for the four case
3383 * change types, except there are complications for folding. Otherwise the
3384 * difference is only which case to change to. To make sure that they all do
3385 * the same thing, the bodies of the functions are extracted out into the
3386 * following two macros. The functions are written with the same variable
3387 * names, and these are known and used inside these macros. It would be
3388 * better, of course, to have inline functions to do it, but since different
3389 * macros are called, depending on which case is being changed to, this is not
3390 * feasible in C (to khw's knowledge). Two macros are created so that the fold
3391 * function can start with the common start macro, then finish with its special
3392 * handling; while the other three cases can just use the common end macro.
3393 *
3394 * The algorithm is to use the proper (passed in) macro or function to change
3395 * the case for code points that are below 256. The macro is used if using
3396 * locale rules for the case change; the function if not. If the code point is
3397 * above 255, it is computed from the input UTF-8, and another macro is called
3398 * to do the conversion. If necessary, the output is converted to UTF-8. If
3399 * using a locale, we have to check that the change did not cross the 255/256
3400 * boundary, see check_locale_boundary_crossing() for further details.
3401 *
3402 * The macros are split with the correct case change for the below-256 case
3403 * stored into 'result', and in the middle of an else clause for the above-255
3404 * case. At that point in the 'else', 'result' is not the final result, but is
3405 * the input code point calculated from the UTF-8. The fold code needs to
3406 * realize all this and take it from there.
3407 *
3408 * If you read the two macros as sequential, it's easier to understand what's
3409 * going on. */
3410#define CASE_CHANGE_BODY_START(locale_flags, LC_L1_change_macro, L1_func, \
3411 L1_func_extra_param) \
a239b1e2 3412 \
eaf412bf
KW
3413 if (flags & (locale_flags)) { \
3414 /* Treat a UTF-8 locale as not being in locale at all */ \
3415 if (IN_UTF8_CTYPE_LOCALE) { \
3416 flags &= ~(locale_flags); \
3417 } \
3418 else { \
3419 _CHECK_AND_WARN_PROBLEMATIC_LOCALE; \
3420 } \
3421 } \
3422 \
3423 if (UTF8_IS_INVARIANT(*p)) { \
3424 if (flags & (locale_flags)) { \
3425 result = LC_L1_change_macro(*p); \
3426 } \
3427 else { \
3428 return L1_func(*p, ustrp, lenp, L1_func_extra_param); \
3429 } \
3430 } \
a239b1e2 3431 else if UTF8_IS_NEXT_CHAR_DOWNGRADEABLE(p, e) { \
eaf412bf
KW
3432 if (flags & (locale_flags)) { \
3433 result = LC_L1_change_macro(EIGHT_BIT_UTF8_TO_NATIVE(*p, \
3434 *(p+1))); \
3435 } \
3436 else { \
3437 return L1_func(EIGHT_BIT_UTF8_TO_NATIVE(*p, *(p+1)), \
3438 ustrp, lenp, L1_func_extra_param); \
3439 } \
3440 } \
fa8ab374
KW
3441 else { /* malformed UTF-8 or ord above 255 */ \
3442 STRLEN len_result; \
fa8ab374
KW
3443 result = utf8n_to_uvchr(p, e - p, &len_result, UTF8_CHECK_ONLY); \
3444 if (len_result == (STRLEN) -1) { \
607313a1
KW
3445 _force_out_malformed_utf8_message(p, e, utf8n_flags, \
3446 1 /* Die */ ); \
fa8ab374 3447 }
eaf412bf
KW
3448
3449#define CASE_CHANGE_BODY_END(locale_flags, change_macro) \
3450 result = change_macro(result, p, ustrp, lenp); \
3451 \
3452 if (flags & (locale_flags)) { \
3453 result = check_locale_boundary_crossing(p, result, ustrp, lenp); \
3454 } \
3455 return result; \
3456 } \
3457 \
3458 /* Here, used locale rules. Convert back to UTF-8 */ \
3459 if (UTF8_IS_INVARIANT(result)) { \
3460 *ustrp = (U8) result; \
3461 *lenp = 1; \
3462 } \
3463 else { \
3464 *ustrp = UTF8_EIGHT_BIT_HI((U8) result); \
3465 *(ustrp + 1) = UTF8_EIGHT_BIT_LO((U8) result); \
3466 *lenp = 2; \
3467 } \
3468 \
3469 return result;
3470
d3e79532 3471/*
87cea99e 3472=for apidoc to_utf8_upper
d3e79532 3473
a239b1e2 3474Instead use L</toUPPER_utf8_safe>.
a1433954 3475
d3e79532
JH
3476=cut */
3477
051a06d4 3478/* Not currently externally documented, and subject to change:
31f05a37
KW
3479 * <flags> is set iff iff the rules from the current underlying locale are to
3480 * be used. */
051a06d4 3481
2104c8d9 3482UV
607313a1
KW
3483Perl__to_utf8_upper_flags(pTHX_ const U8 *p,
3484 const U8 *e,
3485 U8* ustrp,
3486 STRLEN *lenp,
3487 bool flags,
3488 const char * const file,
3489 const int line)
a0ed51b3 3490{
051a06d4 3491 UV result;
607313a1
KW
3492 const U32 utf8n_flags = check_and_deprecate(p, &e, DEPRECATE_TO_UPPER,
3493 cBOOL(flags), file, line);
051a06d4
KW
3494
3495 PERL_ARGS_ASSERT__TO_UTF8_UPPER_FLAGS;
7918f24d 3496
eaf412bf
KW
3497 /* ~0 makes anything non-zero in 'flags' mean we are using locale rules */
3498 /* 2nd char of uc(U+DF) is 'S' */
3499 CASE_CHANGE_BODY_START(~0, toUPPER_LC, _to_upper_title_latin1, 'S');
3500 CASE_CHANGE_BODY_END (~0, CALL_UPPER_CASE);
983ffd37 3501}
a0ed51b3 3502
d3e79532 3503/*
87cea99e 3504=for apidoc to_utf8_title
d3e79532 3505
a239b1e2 3506Instead use L</toTITLE_utf8_safe>.
a1433954 3507
d3e79532
JH
3508=cut */
3509
051a06d4 3510/* Not currently externally documented, and subject to change:
31f05a37
KW
3511 * <flags> is set iff the rules from the current underlying locale are to be
3512 * used. Since titlecase is not defined in POSIX, for other than a
3513 * UTF-8 locale, uppercase is used instead for code points < 256.
445bf929 3514 */
051a06d4 3515
983ffd37 3516UV
607313a1
KW
3517Perl__to_utf8_title_flags(pTHX_ const U8 *p,
3518 const U8 *e,
3519 U8* ustrp,
3520 STRLEN *lenp,
3521 bool flags,
3522 const char * const file,
3523 const int line)
983ffd37 3524{
051a06d4 3525 UV result;
607313a1
KW
3526 const U32 utf8n_flags = check_and_deprecate(p, &e, DEPRECATE_TO_TITLE,
3527 cBOOL(flags), file, line);
051a06d4
KW
3528
3529 PERL_ARGS_ASSERT__TO_UTF8_TITLE_FLAGS;
7918f24d 3530
eaf412bf
KW
3531 /* 2nd char of ucfirst(U+DF) is 's' */
3532 CASE_CHANGE_BODY_START(~0, toUPPER_LC, _to_upper_title_latin1, 's');
3533 CASE_CHANGE_BODY_END (~0, CALL_TITLE_CASE);
a0ed51b3
LW
3534}
3535
d3e79532 3536/*
87cea99e 3537=for apidoc to_utf8_lower
d3e79532 3538
a239b1e2 3539Instead use L</toLOWER_utf8_safe>.
a1433954 3540
d3e79532
JH
3541=cut */
3542
051a06d4 3543/* Not currently externally documented, and subject to change:
31f05a37
KW
3544 * <flags> is set iff iff the rules from the current underlying locale are to
3545 * be used.
3546 */
051a06d4 3547
2104c8d9 3548UV
607313a1
KW
3549Perl__to_utf8_lower_flags(pTHX_ const U8 *p,
3550 const U8 *e,
3551 U8* ustrp,
3552 STRLEN *lenp,
3553 bool flags,
3554 const char * const file,
3555 const int line)
a0ed51b3 3556{
051a06d4 3557 UV result;
607313a1
KW
3558 const U32 utf8n_flags = check_and_deprecate(p, &e, DEPRECATE_TO_LOWER,
3559 cBOOL(flags), file, line);
051a06d4 3560
051a06d4 3561 PERL_ARGS_ASSERT__TO_UTF8_LOWER_FLAGS;
7918f24d 3562
eaf412bf
KW
3563 CASE_CHANGE_BODY_START(~0, toLOWER_LC, to_lower_latin1, 0 /* 0 is dummy */)
3564 CASE_CHANGE_BODY_END (~0, CALL_LOWER_CASE)
b4e400f9
JH
3565}
3566
d3e79532 3567/*
87cea99e 3568=for apidoc to_utf8_fold
d3e79532 3569
a239b1e2 3570Instead use L</toFOLD_utf8_safe>.
a1433954 3571
d3e79532
JH
3572=cut */
3573
051a06d4
KW
3574/* Not currently externally documented, and subject to change,
3575 * in <flags>
31f05a37
KW
3576 * bit FOLD_FLAGS_LOCALE is set iff the rules from the current underlying
3577 * locale are to be used.
051a06d4
KW
3578 * bit FOLD_FLAGS_FULL is set iff full case folds are to be used;
3579 * otherwise simple folds
a0270393
KW
3580 * bit FOLD_FLAGS_NOMIX_ASCII is set iff folds of non-ASCII to ASCII are
3581 * prohibited
445bf929 3582 */
36bb2ab6 3583
b4e400f9 3584UV
607313a1
KW
3585Perl__to_utf8_fold_flags(pTHX_ const U8 *p,
3586 const U8 *e,
3587 U8* ustrp,
3588 STRLEN *lenp,
3589 U8 flags,
3590 const char * const file,
3591 const int line)
b4e400f9 3592{
051a06d4 3593 UV result;
607313a1
KW
3594 const U32 utf8n_flags = check_and_deprecate(p, &e, DEPRECATE_TO_FOLD,
3595 cBOOL(flags), file, line);
051a06d4 3596
36bb2ab6 3597 PERL_ARGS_ASSERT__TO_UTF8_FOLD_FLAGS;
7918f24d 3598
a0270393
KW
3599 /* These are mutually exclusive */
3600 assert (! ((flags & FOLD_FLAGS_LOCALE) && (flags & FOLD_FLAGS_NOMIX_ASCII)));
3601
50ba90ff
KW
3602 assert(p != ustrp); /* Otherwise overwrites */
3603
eaf412bf
KW
3604 CASE_CHANGE_BODY_START(FOLD_FLAGS_LOCALE, toFOLD_LC, _to_fold_latin1,
3605 ((flags) & (FOLD_FLAGS_FULL | FOLD_FLAGS_NOMIX_ASCII)));
31f05a37 3606
eaf412bf 3607 result = CALL_FOLD_CASE(result, p, ustrp, lenp, flags & FOLD_FLAGS_FULL);
a1dde8de 3608
1ca267a5
KW
3609 if (flags & FOLD_FLAGS_LOCALE) {
3610
76f2ffcd 3611# define LONG_S_T LATIN_SMALL_LIGATURE_LONG_S_T_UTF8
0766489e
KW
3612# ifdef LATIN_CAPITAL_LETTER_SHARP_S_UTF8
3613# define CAP_SHARP_S LATIN_CAPITAL_LETTER_SHARP_S_UTF8
76f2ffcd 3614
538e84ed
KW
3615 /* Special case these two characters, as what normally gets
3616 * returned under locale doesn't work */
b59bf0b2 3617 if (memEQs((char *) p, UTF8SKIP(p), CAP_SHARP_S))
1ca267a5 3618 {
ab0b796c
KW
3619 /* diag_listed_as: Can't do %s("%s") on non-UTF-8 locale; resolved to "%s". */
3620 Perl_ck_warner(aTHX_ packWARN(WARN_LOCALE),
3621 "Can't do fc(\"\\x{1E9E}\") on non-UTF-8 locale; "
3622 "resolved to \"\\x{17F}\\x{17F}\".");
1ca267a5
KW
3623 goto return_long_s;
3624 }
0766489e
KW
3625 else
3626#endif
b59bf0b2 3627 if (memEQs((char *) p, UTF8SKIP(p), LONG_S_T))
9fc2026f 3628 {
ab0b796c
KW
3629 /* diag_listed_as: Can't do %s("%s") on non-UTF-8 locale; resolved to "%s". */
3630 Perl_ck_warner(aTHX_ packWARN(WARN_LOCALE),
3631 "Can't do fc(\"\\x{FB05}\") on non-UTF-8 locale; "
3632 "resolved to \"\\x{FB06}\".");
9fc2026f
KW
3633 goto return_ligature_st;
3634 }
74894415
KW
3635
3636#if UNICODE_MAJOR_VERSION == 3 \
3637 && UNICODE_DOT_VERSION == 0 \
3638 && UNICODE_DOT_DOT_VERSION == 1
3639# define DOTTED_I LATIN_CAPITAL_LETTER_I_WITH_DOT_ABOVE_UTF8
3640
3641 /* And special case this on this Unicode version only, for the same
3642 * reaons the other two are special cased. They would cross the
3643 * 255/256 boundary which is forbidden under /l, and so the code
3644 * wouldn't catch that they are equivalent (which they are only in
3645 * this release) */
b59bf0b2 3646 else if (memEQs((char *) p, UTF8SKIP(p), DOTTED_I)) {
74894415
KW
3647 /* diag_listed_as: Can't do %s("%s") on non-UTF-8 locale; resolved to "%s". */
3648 Perl_ck_warner(aTHX_ packWARN(WARN_LOCALE),
3649 "Can't do fc(\"\\x{0130}\") on non-UTF-8 locale; "
3650 "resolved to \"\\x{0131}\".");
3651 goto return_dotless_i;
3652 }
3653#endif
3654
357aadde 3655 return check_locale_boundary_crossing(p, result, ustrp, lenp);
051a06d4 3656 }
a0270393
KW
3657 else if (! (flags & FOLD_FLAGS_NOMIX_ASCII)) {
3658 return result;
3659 }
3660 else {
4a4088c4 3661 /* This is called when changing the case of a UTF-8-encoded
9fc2026f
KW
3662 * character above the ASCII range, and the result should not
3663 * contain an ASCII character. */
a0270393
KW
3664
3665 UV original; /* To store the first code point of <p> */
3666
3667 /* Look at every character in the result; if any cross the
3668 * boundary, the whole thing is disallowed */
3669 U8* s = ustrp;
3670 U8* e = ustrp + *lenp;
3671 while (s < e) {
3672 if (isASCII(*s)) {
3673 /* Crossed, have to return the original */
3674 original = valid_utf8_to_uvchr(p, lenp);
1ca267a5 3675
9fc2026f 3676 /* But in these instances, there is an alternative we can
1ca267a5 3677 * return that is valid */
0766489e
KW
3678 if (original == LATIN_SMALL_LETTER_SHARP_S
3679#ifdef LATIN_CAPITAL_LETTER_SHARP_S /* not defined in early Unicode releases */
3680 || original == LATIN_CAPITAL_LETTER_SHARP_S
3681#endif
3682 ) {
1ca267a5
KW
3683 goto return_long_s;
3684 }
9fc2026f
KW
3685 else if (original == LATIN_SMALL_LIGATURE_LONG_S_T) {
3686 goto return_ligature_st;
3687 }
74894415
KW
3688#if UNICODE_MAJOR_VERSION == 3 \
3689 && UNICODE_DOT_VERSION == 0 \
3690 && UNICODE_DOT_DOT_VERSION == 1
3691
3692 else if (original == LATIN_CAPITAL_LETTER_I_WITH_DOT_ABOVE) {
3693 goto return_dotless_i;
3694 }
3695#endif
a0270393
KW
3696 Copy(p, ustrp, *lenp, char);
3697 return original;
3698 }
3699 s += UTF8SKIP(s);
3700 }
051a06d4 3701
a0270393
KW