1 /*    locale.c
2  *
3  *    Copyright (C) 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001,
4  *    2002, 2003, 2005, 2006, 2007, 2008 by Larry Wall and others
5  *
6  *    You may distribute under the terms of either the GNU General Public
7  *    License or the Artistic License, as specified in the README file.
8  *
9  */
10 
11 /*
12  *      A Elbereth Gilthoniel,
13  *      silivren penna míriel
14  *      o menel aglar elenath!
15  *      Na-chaered palan-díriel
16  *      o galadhremmin ennorath,
17  *      Fanuilos, le linnathon
18  *      nef aear, si nef aearon!
19  *
20  *     [p.238 of _The Lord of the Rings_, II/i: "Many Meetings"]
21  */
22 
23 /* utility functions for handling locale-specific stuff like what
24  * character represents the decimal point.
25  *
26  * All C programs have an underlying locale.  Perl code generally doesn't pay
27  * any attention to it except within the scope of a 'use locale'.  For most
28  * categories, it accomplishes this by just using different operations if it is
29  * in such scope than if not.  However, various libc functions called by Perl
30  * are affected by the LC_NUMERIC category, so there are macros in perl.h that
31  * are used to toggle between the current locale and the C locale depending on
32  * the desired behavior of those functions at the moment.  And, LC_MESSAGES is
33  * switched to the C locale for outputting the message unless within the scope
34  * of 'use locale'.
35  *
36  * This code now has multi-thread-safe locale handling on systems that support
37  * that.  This is completely transparent to most XS code.  On earlier systems,
38  * it would be possible to emulate thread-safe locales, but this likely would
39  * involve a lot of locale switching, and would require XS code changes.
40  * Macros could be written so that the code wouldn't have to know which type of
41  * system is being used.  It's unlikely that we would ever do that, since most
42  * modern systems support thread-safe locales, but there was code written to
43  * this end, and is retained, #ifdef'd out.
44  */
45 
46 #include "EXTERN.h"
47 #define PERL_IN_LOCALE_C
48 #include "perl_langinfo.h"
49 #include "perl.h"
50 
51 #include "reentr.h"
52 
53 #ifdef I_WCHAR
54 #  include <wchar.h>
55 #endif
56 #ifdef I_WCTYPE
57 #  include <wctype.h>
58 #endif
59 
60 /* If the environment says to, we can output debugging information during
61  * initialization.  This is done before option parsing, and before any thread
62  * creation, so can be a file-level static */
63 #if ! defined(DEBUGGING)
64 #  define debug_initialization 0
65 #  define DEBUG_INITIALIZATION_set(v)
66 #else
67 static bool debug_initialization = FALSE;
68 #  define DEBUG_INITIALIZATION_set(v) (debug_initialization = v)
69 #endif
70 
71 
72 /* Returns the Unix errno portion; ignoring any others.  This is a macro here
73  * instead of putting it into perl.h, because unclear to khw what should be
74  * done generally. */
75 #define GET_ERRNO   saved_errno
76 
77 /* strlen() of a literal string constant.  We might want this more general,
78  * but using it in just this file for now.  A problem with more generality is
79  * the compiler warnings about comparing unlike signs */
80 #define STRLENs(s)  (sizeof("" s "") - 1)
81 
82 /* Is the C string input 'name' "C" or "POSIX"?  If so, and 'name' is the
83  * return of setlocale(), then this is extremely likely to be the C or POSIX
84  * locale.  However, the output of setlocale() is documented to be opaque, but
85  * the odds are extremely small that it would return these two strings for some
86  * other locale.  Note that VMS in these two locales includes many non-ASCII
87  * characters as controls and punctuation (below are hex bytes):
88  *   cntrl:  84-97 9B-9F
89  *   punct:  A1-A3 A5 A7-AB B0-B3 B5-B7 B9-BD BF-CF D1-DD DF-EF F1-FD
90  * Oddly, none there are listed as alphas, though some represent alphabetics
91  * http://www.nntp.perl.org/group/perl.perl5.porters/2013/02/msg198753.html */
92 #define isNAME_C_OR_POSIX(name)                                              \
93                              (   (name) != NULL                              \
94                               && (( *(name) == 'C' && (*(name + 1)) == '\0') \
95                                    || strEQ((name), "POSIX")))
96 
97 #ifdef USE_LOCALE
98 
99 /* This code keeps a LRU cache of the UTF-8ness of the locales it has so-far
100  * looked up.  This is in the form of a C string:  */
101 
102 #define UTF8NESS_SEP     "\v"
103 #define UTF8NESS_PREFIX  "\f"
104 
105 /* So, the string looks like:
106  *
107  *      \vC\a0\vPOSIX\a0\vam_ET\a0\vaf_ZA.utf8\a1\ven_US.UTF-8\a1\0
108  *
109  * where the digit 0 after the \a indicates that the locale starting just
110  * after the preceding \v is not UTF-8, and the digit 1 mean it is. */
111 
112 STATIC_ASSERT_DECL(STRLENs(UTF8NESS_SEP) == 1);
113 STATIC_ASSERT_DECL(STRLENs(UTF8NESS_PREFIX) == 1);
114 
115 #define C_and_POSIX_utf8ness    UTF8NESS_SEP "C"     UTF8NESS_PREFIX "0"    \
116                                 UTF8NESS_SEP "POSIX" UTF8NESS_PREFIX "0"
117 
118 /* The cache is initialized to C_and_POSIX_utf8ness at start up.  These are
119  * kept there always.  The remining portion of the cache is LRU, with the
120  * oldest looked-up locale at the tail end */
121 
122 STATIC char *
S_stdize_locale(pTHX_ char * locs)123 S_stdize_locale(pTHX_ char *locs)
124 {
125     /* Standardize the locale name from a string returned by 'setlocale',
126      * possibly modifying that string.
127      *
128      * The typical return value of setlocale() is either
129      * (1) "xx_YY" if the first argument of setlocale() is not LC_ALL
130      * (2) "xa_YY xb_YY ..." if the first argument of setlocale() is LC_ALL
131      *     (the space-separated values represent the various sublocales,
132      *      in some unspecified order).  This is not handled by this function.
133      *
134      * In some platforms it has a form like "LC_SOMETHING=Lang_Country.866\n",
135      * which is harmful for further use of the string in setlocale().  This
136      * function removes the trailing new line and everything up through the '='
137      * */
138 
139     const char * const s = strchr(locs, '=');
140     bool okay = TRUE;
141 
142     PERL_ARGS_ASSERT_STDIZE_LOCALE;
143 
144     if (s) {
145         const char * const t = strchr(s, '.');
146         okay = FALSE;
147         if (t) {
148             const char * const u = strchr(t, '\n');
149             if (u && (u[1] == 0)) {
150                 const STRLEN len = u - s;
151                 Move(s + 1, locs, len, char);
152                 locs[len] = 0;
153                 okay = TRUE;
154             }
155         }
156     }
157 
158     if (!okay)
159         Perl_croak(aTHX_ "Can't fix broken locale name \"%s\"", locs);
160 
161     return locs;
162 }
163 
164 /* Two parallel arrays; first the locale categories Perl uses on this system;
165  * the second array is their names.  These arrays are in mostly arbitrary
166  * order. */
167 
168 const int categories[] = {
169 
170 #    ifdef USE_LOCALE_NUMERIC
171                              LC_NUMERIC,
172 #    endif
173 #    ifdef USE_LOCALE_CTYPE
174                              LC_CTYPE,
175 #    endif
176 #    ifdef USE_LOCALE_COLLATE
177                              LC_COLLATE,
178 #    endif
179 #    ifdef USE_LOCALE_TIME
180                              LC_TIME,
181 #    endif
182 #    ifdef USE_LOCALE_MESSAGES
183                              LC_MESSAGES,
184 #    endif
185 #    ifdef USE_LOCALE_MONETARY
186                              LC_MONETARY,
187 #    endif
188 #    ifdef USE_LOCALE_ADDRESS
189                              LC_ADDRESS,
190 #    endif
191 #    ifdef USE_LOCALE_IDENTIFICATION
192                              LC_IDENTIFICATION,
193 #    endif
194 #    ifdef USE_LOCALE_MEASUREMENT
195                              LC_MEASUREMENT,
196 #    endif
197 #    ifdef USE_LOCALE_PAPER
198                              LC_PAPER,
199 #    endif
200 #    ifdef USE_LOCALE_TELEPHONE
201                              LC_TELEPHONE,
202 #    endif
203 #    ifdef USE_LOCALE_SYNTAX
204                              LC_SYNTAX,
205 #    endif
206 #    ifdef USE_LOCALE_TOD
207                              LC_TOD,
208 #    endif
209 #    ifdef LC_ALL
210                              LC_ALL,
211 #    endif
212                             -1  /* Placeholder because C doesn't allow a
213                                    trailing comma, and it would get complicated
214                                    with all the #ifdef's */
215 };
216 
217 /* The top-most real element is LC_ALL */
218 
219 const char * const category_names[] = {
220 
221 #    ifdef USE_LOCALE_NUMERIC
222                                  "LC_NUMERIC",
223 #    endif
224 #    ifdef USE_LOCALE_CTYPE
225                                  "LC_CTYPE",
226 #    endif
227 #    ifdef USE_LOCALE_COLLATE
228                                  "LC_COLLATE",
229 #    endif
230 #    ifdef USE_LOCALE_TIME
231                                  "LC_TIME",
232 #    endif
233 #    ifdef USE_LOCALE_MESSAGES
234                                  "LC_MESSAGES",
235 #    endif
236 #    ifdef USE_LOCALE_MONETARY
237                                  "LC_MONETARY",
238 #    endif
239 #    ifdef USE_LOCALE_ADDRESS
240                                  "LC_ADDRESS",
241 #    endif
242 #    ifdef USE_LOCALE_IDENTIFICATION
243                                  "LC_IDENTIFICATION",
244 #    endif
245 #    ifdef USE_LOCALE_MEASUREMENT
246                                  "LC_MEASUREMENT",
247 #    endif
248 #    ifdef USE_LOCALE_PAPER
249                                  "LC_PAPER",
250 #    endif
251 #    ifdef USE_LOCALE_TELEPHONE
252                                  "LC_TELEPHONE",
253 #    endif
254 #    ifdef USE_LOCALE_SYNTAX
255                                  "LC_SYNTAX",
256 #    endif
257 #    ifdef USE_LOCALE_TOD
258                                  "LC_TOD",
259 #    endif
260 #    ifdef LC_ALL
261                                  "LC_ALL",
262 #    endif
263                                  NULL  /* Placeholder */
264                             };
265 
266 #  ifdef LC_ALL
267 
268     /* On systems with LC_ALL, it is kept in the highest index position.  (-2
269      * to account for the final unused placeholder element.) */
270 #    define NOMINAL_LC_ALL_INDEX (C_ARRAY_LENGTH(categories) - 2)
271 
272 #  else
273 
274     /* On systems without LC_ALL, we pretend it is there, one beyond the real
275      * top element, hence in the unused placeholder element. */
276 #    define NOMINAL_LC_ALL_INDEX (C_ARRAY_LENGTH(categories) - 1)
277 
278 #  endif
279 
280 /* Pretending there is an LC_ALL element just above allows us to avoid most
281  * special cases.  Most loops through these arrays in the code below are
282  * written like 'for (i = 0; i < NOMINAL_LC_ALL_INDEX; i++)'.  They will work
283  * on either type of system.  But the code must be written to not access the
284  * element at 'LC_ALL_INDEX' except on platforms that have it.  This can be
285  * checked for at compile time by using the #define LC_ALL_INDEX which is only
286  * defined if we do have LC_ALL. */
287 
288 STATIC const char *
S_category_name(const int category)289 S_category_name(const int category)
290 {
291     unsigned int i;
292 
293 #ifdef LC_ALL
294 
295     if (category == LC_ALL) {
296         return "LC_ALL";
297     }
298 
299 #endif
300 
301     for (i = 0; i < NOMINAL_LC_ALL_INDEX; i++) {
302         if (category == categories[i]) {
303             return category_names[i];
304         }
305     }
306 
307     {
308         const char suffix[] = " (unknown)";
309         int temp = category;
310         Size_t length = sizeof(suffix) + 1;
311         char * unknown;
312         dTHX;
313 
314         if (temp < 0) {
315             length++;
316             temp = - temp;
317         }
318 
319         /* Calculate the number of digits */
320         while (temp >= 10) {
321             temp /= 10;
322             length++;
323         }
324 
325         Newx(unknown, length, char);
326         my_snprintf(unknown, length, "%d%s", category, suffix);
327         SAVEFREEPV(unknown);
328         return unknown;
329     }
330 }
331 
332 /* Now create LC_foo_INDEX #defines for just those categories on this system */
333 #  ifdef USE_LOCALE_NUMERIC
334 #    define LC_NUMERIC_INDEX            0
335 #    define _DUMMY_NUMERIC              LC_NUMERIC_INDEX
336 #  else
337 #    define _DUMMY_NUMERIC              -1
338 #  endif
339 #  ifdef USE_LOCALE_CTYPE
340 #    define LC_CTYPE_INDEX              _DUMMY_NUMERIC + 1
341 #    define _DUMMY_CTYPE                LC_CTYPE_INDEX
342 #  else
343 #    define _DUMMY_CTYPE                _DUMMY_NUMERIC
344 #  endif
345 #  ifdef USE_LOCALE_COLLATE
346 #    define LC_COLLATE_INDEX            _DUMMY_CTYPE + 1
347 #    define _DUMMY_COLLATE              LC_COLLATE_INDEX
348 #  else
349 #    define _DUMMY_COLLATE              _DUMMY_CTYPE
350 #  endif
351 #  ifdef USE_LOCALE_TIME
352 #    define LC_TIME_INDEX               _DUMMY_COLLATE + 1
353 #    define _DUMMY_TIME                 LC_TIME_INDEX
354 #  else
355 #    define _DUMMY_TIME                 _DUMMY_COLLATE
356 #  endif
357 #  ifdef USE_LOCALE_MESSAGES
358 #    define LC_MESSAGES_INDEX           _DUMMY_TIME + 1
359 #    define _DUMMY_MESSAGES             LC_MESSAGES_INDEX
360 #  else
361 #    define _DUMMY_MESSAGES             _DUMMY_TIME
362 #  endif
363 #  ifdef USE_LOCALE_MONETARY
364 #    define LC_MONETARY_INDEX           _DUMMY_MESSAGES + 1
365 #    define _DUMMY_MONETARY             LC_MONETARY_INDEX
366 #  else
367 #    define _DUMMY_MONETARY             _DUMMY_MESSAGES
368 #  endif
369 #  ifdef USE_LOCALE_ADDRESS
370 #    define LC_ADDRESS_INDEX            _DUMMY_MONETARY + 1
371 #    define _DUMMY_ADDRESS              LC_ADDRESS_INDEX
372 #  else
373 #    define _DUMMY_ADDRESS              _DUMMY_MONETARY
374 #  endif
375 #  ifdef USE_LOCALE_IDENTIFICATION
376 #    define LC_IDENTIFICATION_INDEX     _DUMMY_ADDRESS + 1
377 #    define _DUMMY_IDENTIFICATION       LC_IDENTIFICATION_INDEX
378 #  else
379 #    define _DUMMY_IDENTIFICATION       _DUMMY_ADDRESS
380 #  endif
381 #  ifdef USE_LOCALE_MEASUREMENT
382 #    define LC_MEASUREMENT_INDEX        _DUMMY_IDENTIFICATION + 1
383 #    define _DUMMY_MEASUREMENT          LC_MEASUREMENT_INDEX
384 #  else
385 #    define _DUMMY_MEASUREMENT          _DUMMY_IDENTIFICATION
386 #  endif
387 #  ifdef USE_LOCALE_PAPER
388 #    define LC_PAPER_INDEX              _DUMMY_MEASUREMENT + 1
389 #    define _DUMMY_PAPER                LC_PAPER_INDEX
390 #  else
391 #    define _DUMMY_PAPER                _DUMMY_MEASUREMENT
392 #  endif
393 #  ifdef USE_LOCALE_TELEPHONE
394 #    define LC_TELEPHONE_INDEX          _DUMMY_PAPER + 1
395 #    define _DUMMY_TELEPHONE            LC_TELEPHONE_INDEX
396 #  else
397 #    define _DUMMY_TELEPHONE            _DUMMY_PAPER
398 #  endif
399 #  ifdef USE_LOCALE_SYNTAX
400 #    define LC_SYNTAX_INDEX             _DUMMY_TELEPHONE + 1
401 #    define _DUMMY_SYNTAX               LC_SYNTAX_INDEX
402 #  else
403 #    define _DUMMY_SYNTAX               _DUMMY_TELEPHONE
404 #  endif
405 #  ifdef USE_LOCALE_TOD
406 #    define LC_TOD_INDEX                _DUMMY_SYNTAX + 1
407 #    define _DUMMY_TOD                  LC_TOD_INDEX
408 #  else
409 #    define _DUMMY_TOD                  _DUMMY_SYNTAX
410 #  endif
411 #  ifdef LC_ALL
412 #    define LC_ALL_INDEX                _DUMMY_TOD + 1
413 #  endif
414 #endif /* ifdef USE_LOCALE */
415 
416 /* Windows requres a customized base-level setlocale() */
417 #ifdef WIN32
418 #  define my_setlocale(cat, locale) win32_setlocale(cat, locale)
419 #else
420 #  define my_setlocale(cat, locale) setlocale(cat, locale)
421 #endif
422 
423 #ifndef USE_POSIX_2008_LOCALE
424 
425 /* "do_setlocale_c" is intended to be called when the category is a constant
426  * known at compile time; "do_setlocale_r", not known until run time  */
427 #  define do_setlocale_c(cat, locale) my_setlocale(cat, locale)
428 #  define do_setlocale_r(cat, locale) my_setlocale(cat, locale)
429 #  define FIX_GLIBC_LC_MESSAGES_BUG(i)
430 
431 #else   /* Below uses POSIX 2008 */
432 
433 /* We emulate setlocale with our own function.  LC_foo is not valid for the
434  * POSIX 2008 functions.  Instead LC_foo_MASK is used, which we use an array
435  * lookup to convert to.  At compile time we have defined LC_foo_INDEX as the
436  * proper offset into the array 'category_masks[]'.  At runtime, we have to
437  * search through the array (as the actual numbers may not be small contiguous
438  * positive integers which would lend themselves to array lookup). */
439 #  define do_setlocale_c(cat, locale)                                       \
440                         emulate_setlocale(cat, locale, cat ## _INDEX, TRUE)
441 #  define do_setlocale_r(cat, locale) emulate_setlocale(cat, locale, 0, FALSE)
442 
443 #  if ! defined(__GLIBC__) || ! defined(USE_LOCALE_MESSAGES)
444 
445 #    define FIX_GLIBC_LC_MESSAGES_BUG(i)
446 
447 #  else /* Invalidate glibc cache of loaded translations, see [perl #134264] */
448 
449 #    include <libintl.h>
450 #    define FIX_GLIBC_LC_MESSAGES_BUG(i)                                        \
451         STMT_START {                                                        \
452             if ((i) == LC_MESSAGES_INDEX) {                                 \
453                 textdomain(textdomain(NULL));                               \
454             }                                                               \
455         } STMT_END
456 
457 #  endif
458 
459 /* A third array, parallel to the ones above to map from category to its
460  * equivalent mask */
461 const int category_masks[] = {
462 #  ifdef USE_LOCALE_NUMERIC
463                                 LC_NUMERIC_MASK,
464 #  endif
465 #  ifdef USE_LOCALE_CTYPE
466                                 LC_CTYPE_MASK,
467 #  endif
468 #  ifdef USE_LOCALE_COLLATE
469                                 LC_COLLATE_MASK,
470 #  endif
471 #  ifdef USE_LOCALE_TIME
472                                 LC_TIME_MASK,
473 #  endif
474 #  ifdef USE_LOCALE_MESSAGES
475                                 LC_MESSAGES_MASK,
476 #  endif
477 #  ifdef USE_LOCALE_MONETARY
478                                 LC_MONETARY_MASK,
479 #  endif
480 #  ifdef USE_LOCALE_ADDRESS
481                                 LC_ADDRESS_MASK,
482 #  endif
483 #  ifdef USE_LOCALE_IDENTIFICATION
484                                 LC_IDENTIFICATION_MASK,
485 #  endif
486 #  ifdef USE_LOCALE_MEASUREMENT
487                                 LC_MEASUREMENT_MASK,
488 #  endif
489 #  ifdef USE_LOCALE_PAPER
490                                 LC_PAPER_MASK,
491 #  endif
492 #  ifdef USE_LOCALE_TELEPHONE
493                                 LC_TELEPHONE_MASK,
494 #  endif
495 #  ifdef USE_LOCALE_SYNTAX
496                                 LC_SYNTAX_MASK,
497 #  endif
498 #  ifdef USE_LOCALE_TOD
499                                 LC_TOD_MASK,
500 #  endif
501                                 /* LC_ALL can't be turned off by a Configure
502                                  * option, and in Posix 2008, should always be
503                                  * here, so compile it in unconditionally.
504                                  * This could catch some glitches at compile
505                                  * time */
506                                 LC_ALL_MASK
507                             };
508 
509 STATIC const char *
S_emulate_setlocale(const int category,const char * locale,unsigned int index,const bool is_index_valid)510 S_emulate_setlocale(const int category,
511                     const char * locale,
512                     unsigned int index,
513                     const bool is_index_valid
514                    )
515 {
516     /* This function effectively performs a setlocale() on just the current
517      * thread; thus it is thread-safe.  It does this by using the POSIX 2008
518      * locale functions to emulate the behavior of setlocale().  Similar to
519      * regular setlocale(), the return from this function points to memory that
520      * can be overwritten by other system calls, so needs to be copied
521      * immediately if you need to retain it.  The difference here is that
522      * system calls besides another setlocale() can overwrite it.
523      *
524      * By doing this, most locale-sensitive functions become thread-safe.  The
525      * exceptions are mostly those that return a pointer to static memory.
526      *
527      * This function takes the same parameters, 'category' and 'locale', that
528      * the regular setlocale() function does, but it also takes two additional
529      * ones.  This is because the 2008 functions don't use a category; instead
530      * they use a corresponding mask.  Because this function operates in both
531      * worlds, it may need one or the other or both.  This function can
532      * calculate the mask from the input category, but to avoid this
533      * calculation, if the caller knows at compile time what the mask is, it
534      * can pass it, setting 'is_index_valid' to TRUE; otherwise the mask
535      * parameter is ignored.
536      *
537      * POSIX 2008, for some sick reason, chose not to provide a method to find
538      * the category name of a locale.  Some vendors have created a
539      * querylocale() function to do just that.  This function is a lot simpler
540      * to implement on systems that have this.  Otherwise, we have to keep
541      * track of what the locale has been set to, so that we can return its
542      * name to emulate setlocale().  It's also possible for C code in some
543      * library to change the locale without us knowing it, though as of
544      * September 2017, there are no occurrences in CPAN of uselocale().  Some
545      * libraries do use setlocale(), but that changes the global locale, and
546      * threads using per-thread locales will just ignore those changes.
547      * Another problem is that without querylocale(), we have to guess at what
548      * was meant by setting a locale of "".  We handle this by not actually
549      * ever setting to "" (unless querylocale exists), but to emulate what we
550      * think should happen for "".
551      */
552 
553     int mask;
554     locale_t old_obj;
555     locale_t new_obj;
556     dTHX;
557 
558 #  ifdef DEBUGGING
559 
560     if (DEBUG_Lv_TEST || debug_initialization) {
561         PerlIO_printf(Perl_debug_log, "%s:%d: emulate_setlocale input=%d (%s), \"%s\", %d, %d\n", __FILE__, __LINE__, category, category_name(category), locale, index, is_index_valid);
562     }
563 
564 #  endif
565 
566     /* If the input mask might be incorrect, calculate the correct one */
567     if (! is_index_valid) {
568         unsigned int i;
569 
570 #  ifdef DEBUGGING
571 
572         if (DEBUG_Lv_TEST || debug_initialization) {
573             PerlIO_printf(Perl_debug_log, "%s:%d: finding index of category %d (%s)\n", __FILE__, __LINE__, category, category_name(category));
574         }
575 
576 #  endif
577 
578         for (i = 0; i <= LC_ALL_INDEX; i++) {
579             if (category == categories[i]) {
580                 index = i;
581                 goto found_index;
582             }
583         }
584 
585         /* Here, we don't know about this category, so can't handle it.
586          * Fallback to the early POSIX usages */
587         Perl_warner(aTHX_ packWARN(WARN_LOCALE),
588                             "Unknown locale category %d; can't set it to %s\n",
589                                                      category, locale);
590         return NULL;
591 
592       found_index: ;
593 
594 #  ifdef DEBUGGING
595 
596         if (DEBUG_Lv_TEST || debug_initialization) {
597             PerlIO_printf(Perl_debug_log, "%s:%d: index is %d for %s\n", __FILE__, __LINE__, index, category_name(category));
598         }
599 
600 #  endif
601 
602     }
603 
604     mask = category_masks[index];
605 
606 #  ifdef DEBUGGING
607 
608     if (DEBUG_Lv_TEST || debug_initialization) {
609         PerlIO_printf(Perl_debug_log, "%s:%d: category name is %s; mask is 0x%x\n", __FILE__, __LINE__, category_names[index], mask);
610     }
611 
612 #  endif
613 
614     /* If just querying what the existing locale is ... */
615     if (locale == NULL) {
616         locale_t cur_obj = uselocale((locale_t) 0);
617 
618 #  ifdef DEBUGGING
619 
620         if (DEBUG_Lv_TEST || debug_initialization) {
621             PerlIO_printf(Perl_debug_log, "%s:%d: emulate_setlocale querying %p\n", __FILE__, __LINE__, cur_obj);
622         }
623 
624 #  endif
625 
626         if (cur_obj == LC_GLOBAL_LOCALE) {
627             return my_setlocale(category, NULL);
628         }
629 
630 #  ifdef HAS_QUERYLOCALE
631 
632         return (char *) querylocale(mask, cur_obj);
633 
634 #  else
635 
636         /* If this assert fails, adjust the size of curlocales in intrpvar.h */
637         STATIC_ASSERT_STMT(C_ARRAY_LENGTH(PL_curlocales) > LC_ALL_INDEX);
638 
639 #    if   defined(_NL_LOCALE_NAME)                                          \
640      &&   defined(DEBUGGING)                                                \
641           /* On systems that accept any locale name, the real underlying    \
642            * locale is often returned by this internal function, so we      \
643            * can't use it */                                                \
644      && ! defined(SETLOCALE_ACCEPTS_ANY_LOCALE_NAME)
645         {
646             /* Internal glibc for querylocale(), but doesn't handle
647              * empty-string ("") locale properly; who knows what other
648              * glitches.  Check for it now, under debug. */
649 
650             char * temp_name = nl_langinfo_l(_NL_LOCALE_NAME(category),
651                                              uselocale((locale_t) 0));
652             /*
653             PerlIO_printf(Perl_debug_log, "%s:%d: temp_name=%s\n", __FILE__, __LINE__, temp_name ? temp_name : "NULL");
654             PerlIO_printf(Perl_debug_log, "%s:%d: index=%d\n", __FILE__, __LINE__, index);
655             PerlIO_printf(Perl_debug_log, "%s:%d: PL_curlocales[index]=%s\n", __FILE__, __LINE__, PL_curlocales[index]);
656             */
657             if (temp_name && PL_curlocales[index] && strNE(temp_name, "")) {
658                 if (         strNE(PL_curlocales[index], temp_name)
659                     && ! (   isNAME_C_OR_POSIX(temp_name)
660                           && isNAME_C_OR_POSIX(PL_curlocales[index]))) {
661 
662 #      ifdef USE_C_BACKTRACE
663 
664                     dump_c_backtrace(Perl_debug_log, 20, 1);
665 
666 #      endif
667 
668                     Perl_croak(aTHX_ "panic: Mismatch between what Perl thinks %s is"
669                                      " (%s) and what internal glibc thinks"
670                                      " (%s)\n", category_names[index],
671                                      PL_curlocales[index], temp_name);
672                 }
673 
674                 return temp_name;
675             }
676         }
677 
678 #    endif
679 
680         /* Without querylocale(), we have to use our record-keeping we've
681          *  done. */
682 
683         if (category != LC_ALL) {
684 
685 #    ifdef DEBUGGING
686 
687             if (DEBUG_Lv_TEST || debug_initialization) {
688                 PerlIO_printf(Perl_debug_log, "%s:%d: emulate_setlocale returning %s\n", __FILE__, __LINE__, PL_curlocales[index]);
689             }
690 
691 #    endif
692 
693             return PL_curlocales[index];
694         }
695         else {  /* For LC_ALL */
696             unsigned int i;
697             Size_t names_len = 0;
698             char * all_string;
699             bool are_all_categories_the_same_locale = TRUE;
700 
701             /* If we have a valid LC_ALL value, just return it */
702             if (PL_curlocales[LC_ALL_INDEX]) {
703 
704 #    ifdef DEBUGGING
705 
706                 if (DEBUG_Lv_TEST || debug_initialization) {
707                     PerlIO_printf(Perl_debug_log, "%s:%d: emulate_setlocale returning %s\n", __FILE__, __LINE__, PL_curlocales[LC_ALL_INDEX]);
708                 }
709 
710 #    endif
711 
712                 return PL_curlocales[LC_ALL_INDEX];
713             }
714 
715             /* Otherwise, we need to construct a string of name=value pairs.
716              * We use the glibc syntax, like
717              *      LC_NUMERIC=C;LC_TIME=en_US.UTF-8;...
718              *  First calculate the needed size.  Along the way, check if all
719              *  the locale names are the same */
720             for (i = 0; i < LC_ALL_INDEX; i++) {
721 
722 #    ifdef DEBUGGING
723 
724                 if (DEBUG_Lv_TEST || debug_initialization) {
725                     PerlIO_printf(Perl_debug_log, "%s:%d: emulate_setlocale i=%d, name=%s, locale=%s\n", __FILE__, __LINE__, i, category_names[i], PL_curlocales[i]);
726                 }
727 
728 #    endif
729 
730                 names_len += strlen(category_names[i])
731                           + 1                       /* '=' */
732                           + strlen(PL_curlocales[i])
733                           + 1;                      /* ';' */
734 
735                 if (i > 0 && strNE(PL_curlocales[i], PL_curlocales[i-1])) {
736                     are_all_categories_the_same_locale = FALSE;
737                 }
738             }
739 
740             /* If they are the same, we don't actually have to construct the
741              * string; we just make the entry in LC_ALL_INDEX valid, and be
742              * that single name */
743             if (are_all_categories_the_same_locale) {
744                 PL_curlocales[LC_ALL_INDEX] = savepv(PL_curlocales[0]);
745                 return PL_curlocales[LC_ALL_INDEX];
746             }
747 
748             names_len++;    /* Trailing '\0' */
749             SAVEFREEPV(Newx(all_string, names_len, char));
750             *all_string = '\0';
751 
752             /* Then fill in the string */
753             for (i = 0; i < LC_ALL_INDEX; i++) {
754 
755 #    ifdef DEBUGGING
756 
757                 if (DEBUG_Lv_TEST || debug_initialization) {
758                     PerlIO_printf(Perl_debug_log, "%s:%d: emulate_setlocale i=%d, name=%s, locale=%s\n", __FILE__, __LINE__, i, category_names[i], PL_curlocales[i]);
759                 }
760 
761 #    endif
762 
763                 my_strlcat(all_string, category_names[i], names_len);
764                 my_strlcat(all_string, "=", names_len);
765                 my_strlcat(all_string, PL_curlocales[i], names_len);
766                 my_strlcat(all_string, ";", names_len);
767             }
768 
769 #    ifdef DEBUGGING
770 
771             if (DEBUG_L_TEST || debug_initialization) {
772                 PerlIO_printf(Perl_debug_log, "%s:%d: emulate_setlocale returning %s\n", __FILE__, __LINE__, all_string);
773             }
774 
775     #endif
776 
777             return all_string;
778         }
779 
780 #    ifdef EINVAL
781 
782         SETERRNO(EINVAL, LIB_INVARG);
783 
784 #    endif
785 
786         return NULL;
787 
788 #  endif
789 
790     }   /* End of this being setlocale(LC_foo, NULL) */
791 
792     /* Here, we are switching locales. */
793 
794 #  ifndef HAS_QUERYLOCALE
795 
796     if (strEQ(locale, "")) {
797 
798         /* For non-querylocale() systems, we do the setting of "" ourselves to
799          * be sure that we really know what's going on.  We follow the Linux
800          * documented behavior (but if that differs from the actual behavior,
801          * this won't work exactly as the OS implements).  We go out and
802          * examine the environment based on our understanding of how the system
803          * works, and use that to figure things out */
804 
805         const char * const lc_all = PerlEnv_getenv("LC_ALL");
806 
807         /* Use any "LC_ALL" environment variable, as it overrides everything
808          * else. */
809         if (lc_all && strNE(lc_all, "")) {
810             locale = lc_all;
811         }
812         else {
813 
814             /* Otherwise, we need to dig deeper.  Unless overridden, the
815              * default is the LANG environment variable; if it doesn't exist,
816              * then "C" */
817 
818             const char * default_name;
819 
820             default_name = PerlEnv_getenv("LANG");
821 
822             if (! default_name || strEQ(default_name, "")) {
823                 default_name = "C";
824             }
825 
826             if (category != LC_ALL) {
827                 const char * const name = PerlEnv_getenv(category_names[index]);
828 
829                 /* Here we are setting a single category.  Assume will have the
830                  * default name */
831                 locale = default_name;
832 
833                 /* But then look for an overriding environment variable */
834                 if (name && strNE(name, "")) {
835                     locale = name;
836                 }
837             }
838             else {
839                 bool did_override = FALSE;
840                 unsigned int i;
841 
842                 /* Here, we are getting LC_ALL.  Any categories that don't have
843                  * a corresponding environment variable set should be set to
844                  * LANG, or to "C" if there is no LANG.  If no individual
845                  * categories differ from this, we can just set LC_ALL.  This
846                  * is buggy on systems that have extra categories that we don't
847                  * know about.  If there is an environment variable that sets
848                  * that category, we won't know to look for it, and so our use
849                  * of LANG or "C" improperly overrides it.  On the other hand,
850                  * if we don't do what is done here, and there is no
851                  * environment variable, the category's locale should be set to
852                  * LANG or "C".  So there is no good solution.  khw thinks the
853                  * best is to look at systems to see what categories they have,
854                  * and include them, and then to assume that we know the
855                  * complete set */
856 
857                 for (i = 0; i < LC_ALL_INDEX; i++) {
858                     const char * const env_override
859                                             = PerlEnv_getenv(category_names[i]);
860                     const char * this_locale = (   env_override
861                                                 && strNE(env_override, ""))
862                                                ? env_override
863                                                : default_name;
864                     if (! emulate_setlocale(categories[i], this_locale, i, TRUE))
865                     {
866                         return NULL;
867                     }
868 
869                     if (strNE(this_locale, default_name)) {
870                         did_override = TRUE;
871                     }
872                 }
873 
874                 /* If all the categories are the same, we can set LC_ALL to
875                  * that */
876                 if (! did_override) {
877                     locale = default_name;
878                 }
879                 else {
880 
881                     /* Here, LC_ALL is no longer valid, as some individual
882                      * categories don't match it.  We call ourselves
883                      * recursively, as that will execute the code that
884                      * generates the proper locale string for this situation.
885                      * We don't do the remainder of this function, as that is
886                      * to update our records, and we've just done that for the
887                      * individual categories in the loop above, and doing so
888                      * would cause LC_ALL to be done as well */
889                     return emulate_setlocale(LC_ALL, NULL, LC_ALL_INDEX, TRUE);
890                 }
891             }
892         }
893     }   /* End of this being setlocale(LC_foo, "") */
894     else if (strchr(locale, ';')) {
895 
896         /* LC_ALL may actually incude a conglomeration of various categories.
897          * Without querylocale, this code uses the glibc (as of this writing)
898          * syntax for representing that, but that is not a stable API, and
899          * other platforms do it differently, so we have to handle all cases
900          * ourselves */
901 
902         unsigned int i;
903         const char * s = locale;
904         const char * e = locale + strlen(locale);
905         const char * p = s;
906         const char * category_end;
907         const char * name_start;
908         const char * name_end;
909 
910         /* If the string that gives what to set doesn't include all categories,
911          * the omitted ones get set to "C".  To get this behavior, first set
912          * all the individual categories to "C", and override the furnished
913          * ones below */
914         for (i = 0; i < LC_ALL_INDEX; i++) {
915             if (! emulate_setlocale(categories[i], "C", i, TRUE)) {
916                 return NULL;
917             }
918         }
919 
920         while (s < e) {
921 
922             /* Parse through the category */
923             while (isWORDCHAR(*p)) {
924                 p++;
925             }
926             category_end = p;
927 
928             if (*p++ != '=') {
929                 Perl_croak(aTHX_
930                     "panic: %s: %d: Unexpected character in locale name '%02X",
931                     __FILE__, __LINE__, *(p-1));
932             }
933 
934             /* Parse through the locale name */
935             name_start = p;
936             while (p < e && *p != ';') {
937                 if (! isGRAPH(*p)) {
938                     Perl_croak(aTHX_
939                         "panic: %s: %d: Unexpected character in locale name '%02X",
940                         __FILE__, __LINE__, *(p-1));
941                 }
942                 p++;
943             }
944             name_end = p;
945 
946             /* Space past the semi-colon */
947             if (p < e) {
948                 p++;
949             }
950 
951             /* Find the index of the category name in our lists */
952             for (i = 0; i < LC_ALL_INDEX; i++) {
953                 char * individ_locale;
954 
955                 /* Keep going if this isn't the index.  The strnNE() avoids a
956                  * Perl_form(), but would fail if ever a category name could be
957                  * a substring of another one, like if there were a
958                  * "LC_TIME_DATE" */
959                 if strnNE(s, category_names[i], category_end - s) {
960                     continue;
961                 }
962 
963                 /* If this index is for the single category we're changing, we
964                  * have found the locale to set it to. */
965                 if (category == categories[i]) {
966                     locale = Perl_form(aTHX_ "%.*s",
967                                              (int) (name_end - name_start),
968                                              name_start);
969                     goto ready_to_set;
970                 }
971 
972                 assert(category == LC_ALL);
973                 individ_locale = Perl_form(aTHX_ "%.*s",
974                                     (int) (name_end - name_start), name_start);
975                 if (! emulate_setlocale(categories[i], individ_locale, i, TRUE))
976                 {
977                     return NULL;
978                 }
979             }
980 
981             s = p;
982         }
983 
984         /* Here we have set all the individual categories by recursive calls.
985          * These collectively should have fixed up LC_ALL, so can just query
986          * what that now is */
987         assert(category == LC_ALL);
988 
989         return do_setlocale_c(LC_ALL, NULL);
990     }   /* End of this being setlocale(LC_ALL,
991            "LC_CTYPE=foo;LC_NUMERIC=bar;...") */
992 
993   ready_to_set: ;
994 
995     /* Here at the end of having to deal with the absence of querylocale().
996      * Some cases have already been fully handled by recursive calls to this
997      * function.  But at this point, we haven't dealt with those, but are now
998      * prepared to, knowing what the locale name to set this category to is.
999      * This would have come for free if this system had had querylocale() */
1000 
1001 #  endif  /* end of ! querylocale */
1002 
1003     assert(PL_C_locale_obj);
1004 
1005     /* Switching locales generally entails freeing the current one's space (at
1006      * the C library's discretion).  We need to stop using that locale before
1007      * the switch.  So switch to a known locale object that we don't otherwise
1008      * mess with.  This returns the locale object in effect at the time of the
1009      * switch. */
1010     old_obj = uselocale(PL_C_locale_obj);
1011 
1012 #  ifdef DEBUGGING
1013 
1014     if (DEBUG_Lv_TEST || debug_initialization) {
1015         PerlIO_printf(Perl_debug_log, "%s:%d: emulate_setlocale was using %p\n", __FILE__, __LINE__, old_obj);
1016     }
1017 
1018 #  endif
1019 
1020     if (! old_obj) {
1021 
1022 #  ifdef DEBUGGING
1023 
1024         if (DEBUG_L_TEST || debug_initialization) {
1025             dSAVE_ERRNO;
1026             PerlIO_printf(Perl_debug_log, "%s:%d: emulate_setlocale switching to C failed: %d\n", __FILE__, __LINE__, GET_ERRNO);
1027             RESTORE_ERRNO;
1028         }
1029 
1030 #  endif
1031 
1032         return NULL;
1033     }
1034 
1035 #  ifdef DEBUGGING
1036 
1037     if (DEBUG_Lv_TEST || debug_initialization) {
1038         PerlIO_printf(Perl_debug_log,
1039                       "%s:%d: emulate_setlocale now using %p\n",
1040                       __FILE__, __LINE__, PL_C_locale_obj);
1041     }
1042 
1043 #  endif
1044 
1045     /* If this call is to switch to the LC_ALL C locale, it already exists, and
1046      * in fact, we already have switched to it (in preparation for what
1047      * normally is to come).  But since we're already there, continue to use
1048      * it instead of trying to create a new locale */
1049     if (mask == LC_ALL_MASK && isNAME_C_OR_POSIX(locale)) {
1050 
1051 #  ifdef DEBUGGING
1052 
1053         if (DEBUG_Lv_TEST || debug_initialization) {
1054             PerlIO_printf(Perl_debug_log,
1055                           "%s:%d: will stay in C object\n", __FILE__, __LINE__);
1056         }
1057 
1058 #  endif
1059 
1060         new_obj = PL_C_locale_obj;
1061 
1062         /* We already had switched to the C locale in preparation for freeing
1063          * 'old_obj' */
1064         if (old_obj != LC_GLOBAL_LOCALE && old_obj != PL_C_locale_obj) {
1065             freelocale(old_obj);
1066         }
1067     }
1068     else {
1069         /* If we weren't in a thread safe locale, set so that newlocale() below
1070          * which uses 'old_obj', uses an empty one.  Same for our reserved C
1071          * object.  The latter is defensive coding, so that, even if there is
1072          * some bug, we will never end up trying to modify either of these, as
1073          * if passed to newlocale(), they can be. */
1074         if (old_obj == LC_GLOBAL_LOCALE || old_obj == PL_C_locale_obj) {
1075             old_obj = (locale_t) 0;
1076         }
1077 
1078         /* Ready to create a new locale by modification of the exising one */
1079         new_obj = newlocale(mask, locale, old_obj);
1080 
1081         if (! new_obj) {
1082             dSAVE_ERRNO;
1083 
1084 #  ifdef DEBUGGING
1085 
1086             if (DEBUG_L_TEST || debug_initialization) {
1087                 PerlIO_printf(Perl_debug_log,
1088                               "%s:%d: emulate_setlocale creating new object"
1089                               " failed: %d\n", __FILE__, __LINE__, GET_ERRNO);
1090             }
1091 
1092 #  endif
1093 
1094             if (! uselocale(old_obj)) {
1095 
1096 #  ifdef DEBUGGING
1097 
1098                 if (DEBUG_L_TEST || debug_initialization) {
1099                     PerlIO_printf(Perl_debug_log,
1100                                   "%s:%d: switching back failed: %d\n",
1101                                   __FILE__, __LINE__, GET_ERRNO);
1102                 }
1103 
1104 #  endif
1105 
1106             }
1107             RESTORE_ERRNO;
1108             return NULL;
1109         }
1110 
1111 #  ifdef DEBUGGING
1112 
1113         if (DEBUG_Lv_TEST || debug_initialization) {
1114             PerlIO_printf(Perl_debug_log,
1115                           "%s:%d: emulate_setlocale created %p",
1116                           __FILE__, __LINE__, new_obj);
1117             if (old_obj) {
1118                 PerlIO_printf(Perl_debug_log,
1119                               "; should have freed %p", old_obj);
1120             }
1121             PerlIO_printf(Perl_debug_log, "\n");
1122         }
1123 
1124 #  endif
1125 
1126         /* And switch into it */
1127         if (! uselocale(new_obj)) {
1128             dSAVE_ERRNO;
1129 
1130 #  ifdef DEBUGGING
1131 
1132             if (DEBUG_L_TEST || debug_initialization) {
1133                 PerlIO_printf(Perl_debug_log,
1134                               "%s:%d: emulate_setlocale switching to new object"
1135                               " failed\n", __FILE__, __LINE__);
1136             }
1137 
1138 #  endif
1139 
1140             if (! uselocale(old_obj)) {
1141 
1142 #  ifdef DEBUGGING
1143 
1144                 if (DEBUG_L_TEST || debug_initialization) {
1145                     PerlIO_printf(Perl_debug_log,
1146                                   "%s:%d: switching back failed: %d\n",
1147                                   __FILE__, __LINE__, GET_ERRNO);
1148                 }
1149 
1150 #  endif
1151 
1152             }
1153             freelocale(new_obj);
1154             RESTORE_ERRNO;
1155             return NULL;
1156         }
1157     }
1158 
1159 #  ifdef DEBUGGING
1160 
1161     if (DEBUG_Lv_TEST || debug_initialization) {
1162         PerlIO_printf(Perl_debug_log,
1163                       "%s:%d: emulate_setlocale now using %p\n",
1164                       __FILE__, __LINE__, new_obj);
1165     }
1166 
1167 #  endif
1168 
1169     /* We are done, except for updating our records (if the system doesn't keep
1170      * them) and in the case of locale "", we don't actually know what the
1171      * locale that got switched to is, as it came from the environment.  So
1172      * have to find it */
1173 
1174 #  ifdef HAS_QUERYLOCALE
1175 
1176     if (strEQ(locale, "")) {
1177         locale = querylocale(mask, new_obj);
1178     }
1179 
1180 #  else
1181 
1182     /* Here, 'locale' is the return value */
1183 
1184     /* Without querylocale(), we have to update our records */
1185 
1186     if (category == LC_ALL) {
1187         unsigned int i;
1188 
1189         /* For LC_ALL, we change all individual categories to correspond */
1190                               /* PL_curlocales is a parallel array, so has same
1191                                * length as 'categories' */
1192         for (i = 0; i <= LC_ALL_INDEX; i++) {
1193             Safefree(PL_curlocales[i]);
1194             PL_curlocales[i] = savepv(locale);
1195         }
1196 
1197         FIX_GLIBC_LC_MESSAGES_BUG(LC_MESSAGES_INDEX);
1198     }
1199     else {
1200 
1201         /* For a single category, if it's not the same as the one in LC_ALL, we
1202          * nullify LC_ALL */
1203 
1204         if (PL_curlocales[LC_ALL_INDEX] && strNE(PL_curlocales[LC_ALL_INDEX], locale)) {
1205             Safefree(PL_curlocales[LC_ALL_INDEX]);
1206             PL_curlocales[LC_ALL_INDEX] = NULL;
1207         }
1208 
1209         /* Then update the category's record */
1210         Safefree(PL_curlocales[index]);
1211         PL_curlocales[index] = savepv(locale);
1212 
1213         FIX_GLIBC_LC_MESSAGES_BUG(index);
1214     }
1215 
1216 #  endif
1217 
1218     return locale;
1219 }
1220 
1221 #endif /* USE_POSIX_2008_LOCALE */
1222 
1223 #ifdef USE_LOCALE
1224 
1225 STATIC void
S_set_numeric_radix(pTHX_ const bool use_locale)1226 S_set_numeric_radix(pTHX_ const bool use_locale)
1227 {
1228     /* If 'use_locale' is FALSE, set to use a dot for the radix character.  If
1229      * TRUE, use the radix character derived from the current locale */
1230 
1231 #if defined(USE_LOCALE_NUMERIC) && (   defined(HAS_LOCALECONV)              \
1232                                     || defined(HAS_NL_LANGINFO))
1233 
1234     const char * radix = (use_locale)
1235                          ? my_nl_langinfo(RADIXCHAR, FALSE)
1236                                         /* FALSE => already in dest locale */
1237                          : ".";
1238 
1239         sv_setpv(PL_numeric_radix_sv, radix);
1240 
1241     /* If this is valid UTF-8 that isn't totally ASCII, and we are in
1242         * a UTF-8 locale, then mark the radix as being in UTF-8 */
1243     if (is_utf8_non_invariant_string((U8 *) SvPVX(PL_numeric_radix_sv),
1244                                             SvCUR(PL_numeric_radix_sv))
1245         && _is_cur_LC_category_utf8(LC_NUMERIC))
1246     {
1247         SvUTF8_on(PL_numeric_radix_sv);
1248     }
1249 
1250 #  ifdef DEBUGGING
1251 
1252     if (DEBUG_L_TEST || debug_initialization) {
1253         PerlIO_printf(Perl_debug_log, "Locale radix is '%s', ?UTF-8=%d\n",
1254                                            SvPVX(PL_numeric_radix_sv),
1255                                            cBOOL(SvUTF8(PL_numeric_radix_sv)));
1256     }
1257 
1258 #  endif
1259 #else
1260 
1261     PERL_UNUSED_ARG(use_locale);
1262 
1263 #endif /* USE_LOCALE_NUMERIC and can find the radix char */
1264 
1265 }
1266 
1267 STATIC void
S_new_numeric(pTHX_ const char * newnum)1268 S_new_numeric(pTHX_ const char *newnum)
1269 {
1270 
1271 #ifndef USE_LOCALE_NUMERIC
1272 
1273     PERL_UNUSED_ARG(newnum);
1274 
1275 #else
1276 
1277     /* Called after each libc setlocale() call affecting LC_NUMERIC, to tell
1278      * core Perl this and that 'newnum' is the name of the new locale.
1279      * It installs this locale as the current underlying default.
1280      *
1281      * The default locale and the C locale can be toggled between by use of the
1282      * set_numeric_underlying() and set_numeric_standard() functions, which
1283      * should probably not be called directly, but only via macros like
1284      * SET_NUMERIC_STANDARD() in perl.h.
1285      *
1286      * The toggling is necessary mainly so that a non-dot radix decimal point
1287      * character can be output, while allowing internal calculations to use a
1288      * dot.
1289      *
1290      * This sets several interpreter-level variables:
1291      * PL_numeric_name  The underlying locale's name: a copy of 'newnum'
1292      * PL_numeric_underlying  A boolean indicating if the toggled state is such
1293      *                  that the current locale is the program's underlying
1294      *                  locale
1295      * PL_numeric_standard An int indicating if the toggled state is such
1296      *                  that the current locale is the C locale or
1297      *                  indistinguishable from the C locale.  If non-zero, it
1298      *                  is in C; if > 1, it means it may not be toggled away
1299      *                  from C.
1300      * PL_numeric_underlying_is_standard   A bool kept by this function
1301      *                  indicating that the underlying locale and the standard
1302      *                  C locale are indistinguishable for the purposes of
1303      *                  LC_NUMERIC.  This happens when both of the above two
1304      *                  variables are true at the same time.  (Toggling is a
1305      *                  no-op under these circumstances.)  This variable is
1306      *                  used to avoid having to recalculate.
1307      */
1308 
1309     char *save_newnum;
1310 
1311     if (! newnum) {
1312         Safefree(PL_numeric_name);
1313         PL_numeric_name = NULL;
1314         PL_numeric_standard = TRUE;
1315         PL_numeric_underlying = TRUE;
1316         PL_numeric_underlying_is_standard = TRUE;
1317         return;
1318     }
1319 
1320     save_newnum = stdize_locale(savepv(newnum));
1321     PL_numeric_underlying = TRUE;
1322     PL_numeric_standard = isNAME_C_OR_POSIX(save_newnum);
1323 
1324 #ifndef TS_W32_BROKEN_LOCALECONV
1325 
1326     /* If its name isn't C nor POSIX, it could still be indistinguishable from
1327      * them.  But on broken Windows systems calling my_nl_langinfo() for
1328      * THOUSEP can currently (but rarely) cause a race, so avoid doing that,
1329      * and just always change the locale if not C nor POSIX on those systems */
1330     if (! PL_numeric_standard) {
1331         PL_numeric_standard = cBOOL(strEQ(".", my_nl_langinfo(RADIXCHAR,
1332                                             FALSE /* Don't toggle locale */  ))
1333                                  && strEQ("",  my_nl_langinfo(THOUSEP, FALSE)));
1334     }
1335 
1336 #endif
1337 
1338     /* Save the new name if it isn't the same as the previous one, if any */
1339     if (! PL_numeric_name || strNE(PL_numeric_name, save_newnum)) {
1340         Safefree(PL_numeric_name);
1341         PL_numeric_name = save_newnum;
1342     }
1343     else {
1344         Safefree(save_newnum);
1345     }
1346 
1347     PL_numeric_underlying_is_standard = PL_numeric_standard;
1348 
1349 #  ifdef HAS_POSIX_2008_LOCALE
1350 
1351     PL_underlying_numeric_obj = newlocale(LC_NUMERIC_MASK,
1352                                           PL_numeric_name,
1353                                           PL_underlying_numeric_obj);
1354 
1355 #endif
1356 
1357     if (DEBUG_L_TEST || debug_initialization) {
1358         PerlIO_printf(Perl_debug_log, "Called new_numeric with %s, PL_numeric_name=%s\n", newnum, PL_numeric_name);
1359     }
1360 
1361     /* Keep LC_NUMERIC in the C locale.  This is for XS modules, so they don't
1362      * have to worry about the radix being a non-dot.  (Core operations that
1363      * need the underlying locale change to it temporarily). */
1364     if (PL_numeric_standard) {
1365         set_numeric_radix(0);
1366     }
1367     else {
1368         set_numeric_standard();
1369     }
1370 
1371 #endif /* USE_LOCALE_NUMERIC */
1372 
1373 }
1374 
1375 void
Perl_set_numeric_standard(pTHX)1376 Perl_set_numeric_standard(pTHX)
1377 {
1378 
1379 #ifdef USE_LOCALE_NUMERIC
1380 
1381     /* Toggle the LC_NUMERIC locale to C.  Most code should use the macros like
1382      * SET_NUMERIC_STANDARD() in perl.h instead of calling this directly.  The
1383      * macro avoids calling this routine if toggling isn't necessary according
1384      * to our records (which could be wrong if some XS code has changed the
1385      * locale behind our back) */
1386 
1387 #  ifdef DEBUGGING
1388 
1389     if (DEBUG_L_TEST || debug_initialization) {
1390         PerlIO_printf(Perl_debug_log,
1391                           "Setting LC_NUMERIC locale to standard C\n");
1392     }
1393 
1394 #  endif
1395 
1396     do_setlocale_c(LC_NUMERIC, "C");
1397     PL_numeric_standard = TRUE;
1398     PL_numeric_underlying = PL_numeric_underlying_is_standard;
1399     set_numeric_radix(0);
1400 
1401 #endif /* USE_LOCALE_NUMERIC */
1402 
1403 }
1404 
1405 void
Perl_set_numeric_underlying(pTHX)1406 Perl_set_numeric_underlying(pTHX)
1407 {
1408 
1409 #ifdef USE_LOCALE_NUMERIC
1410 
1411     /* Toggle the LC_NUMERIC locale to the current underlying default.  Most
1412      * code should use the macros like SET_NUMERIC_UNDERLYING() in perl.h
1413      * instead of calling this directly.  The macro avoids calling this routine
1414      * if toggling isn't necessary according to our records (which could be
1415      * wrong if some XS code has changed the locale behind our back) */
1416 
1417 #  ifdef DEBUGGING
1418 
1419     if (DEBUG_L_TEST || debug_initialization) {
1420         PerlIO_printf(Perl_debug_log,
1421                           "Setting LC_NUMERIC locale to %s\n",
1422                           PL_numeric_name);
1423     }
1424 
1425 #  endif
1426 
1427     do_setlocale_c(LC_NUMERIC, PL_numeric_name);
1428     PL_numeric_standard = PL_numeric_underlying_is_standard;
1429     PL_numeric_underlying = TRUE;
1430     set_numeric_radix(! PL_numeric_standard);
1431 
1432 #endif /* USE_LOCALE_NUMERIC */
1433 
1434 }
1435 
1436 /*
1437  * Set up for a new ctype locale.
1438  */
1439 STATIC void
S_new_ctype(pTHX_ const char * newctype)1440 S_new_ctype(pTHX_ const char *newctype)
1441 {
1442 
1443 #ifndef USE_LOCALE_CTYPE
1444 
1445     PERL_UNUSED_ARG(newctype);
1446     PERL_UNUSED_CONTEXT;
1447 
1448 #else
1449 
1450     /* Called after each libc setlocale() call affecting LC_CTYPE, to tell
1451      * core Perl this and that 'newctype' is the name of the new locale.
1452      *
1453      * This function sets up the folding arrays for all 256 bytes, assuming
1454      * that tofold() is tolc() since fold case is not a concept in POSIX,
1455      *
1456      * Any code changing the locale (outside this file) should use
1457      * Perl_setlocale or POSIX::setlocale, which call this function.  Therefore
1458      * this function should be called directly only from this file and from
1459      * POSIX::setlocale() */
1460 
1461     unsigned int i;
1462 
1463     /* Don't check for problems if we are suppressing the warnings */
1464     bool check_for_problems = ckWARN_d(WARN_LOCALE) || UNLIKELY(DEBUG_L_TEST);
1465     bool maybe_utf8_turkic = FALSE;
1466 
1467     PERL_ARGS_ASSERT_NEW_CTYPE;
1468 
1469     /* We will replace any bad locale warning with 1) nothing if the new one is
1470      * ok; or 2) a new warning for the bad new locale */
1471     if (PL_warn_locale) {
1472         SvREFCNT_dec_NN(PL_warn_locale);
1473         PL_warn_locale = NULL;
1474     }
1475 
1476     PL_in_utf8_CTYPE_locale = _is_cur_LC_category_utf8(LC_CTYPE);
1477 
1478     /* A UTF-8 locale gets standard rules.  But note that code still has to
1479      * handle this specially because of the three problematic code points */
1480     if (PL_in_utf8_CTYPE_locale) {
1481         Copy(PL_fold_latin1, PL_fold_locale, 256, U8);
1482 
1483         /* UTF-8 locales can have special handling for 'I' and 'i' if they are
1484          * Turkic.  Make sure these two are the only anomalies.  (We don't use
1485          * towupper and towlower because they aren't in C89.) */
1486 
1487 #if defined(HAS_TOWUPPER) && defined (HAS_TOWLOWER)
1488 
1489         if (towupper('i') == 0x130 && towlower('I') == 0x131) {
1490 
1491 #else
1492 
1493         if (toupper('i') == 'i' && tolower('I') == 'I') {
1494 
1495 #endif
1496             check_for_problems = TRUE;
1497             maybe_utf8_turkic = TRUE;
1498         }
1499     }
1500 
1501     /* We don't populate the other lists if a UTF-8 locale, but do check that
1502      * everything works as expected, unless checking turned off */
1503     if (check_for_problems || ! PL_in_utf8_CTYPE_locale) {
1504         /* Assume enough space for every character being bad.  4 spaces each
1505          * for the 94 printable characters that are output like "'x' "; and 5
1506          * spaces each for "'\\' ", "'\t' ", and "'\n' "; plus a terminating
1507          * NUL */
1508         char bad_chars_list[ (94 * 4) + (3 * 5) + 1 ] = { '\0' };
1509         bool multi_byte_locale = FALSE;     /* Assume is a single-byte locale
1510                                                to start */
1511         unsigned int bad_count = 0;         /* Count of bad characters */
1512 
1513         for (i = 0; i < 256; i++) {
1514             if (! PL_in_utf8_CTYPE_locale) {
1515                 if (isupper(i))
1516                     PL_fold_locale[i] = (U8) tolower(i);
1517                 else if (islower(i))
1518                     PL_fold_locale[i] = (U8) toupper(i);
1519                 else
1520                     PL_fold_locale[i] = (U8) i;
1521             }
1522 
1523             /* If checking for locale problems, see if the native ASCII-range
1524              * printables plus \n and \t are in their expected categories in
1525              * the new locale.  If not, this could mean big trouble, upending
1526              * Perl's and most programs' assumptions, like having a
1527              * metacharacter with special meaning become a \w.  Fortunately,
1528              * it's very rare to find locales that aren't supersets of ASCII
1529              * nowadays.  It isn't a problem for most controls to be changed
1530              * into something else; we check only \n and \t, though perhaps \r
1531              * could be an issue as well. */
1532             if (    check_for_problems
1533                 && (isGRAPH_A(i) || isBLANK_A(i) || i == '\n'))
1534             {
1535                 bool is_bad = FALSE;
1536                 char name[4] = { '\0' };
1537 
1538                 /* Convert the name into a string */
1539                 if (isGRAPH_A(i)) {
1540                     name[0] = i;
1541                     name[1] = '\0';
1542                 }
1543                 else if (i == '\n') {
1544                     my_strlcpy(name, "\\n", sizeof(name));
1545                 }
1546                 else if (i == '\t') {
1547                     my_strlcpy(name, "\\t", sizeof(name));
1548                 }
1549                 else {
1550                     assert(i == ' ');
1551                     my_strlcpy(name, "' '", sizeof(name));
1552                 }
1553 
1554                 /* Check each possibe class */
1555                 if (UNLIKELY(cBOOL(isalnum(i)) != cBOOL(isALPHANUMERIC_A(i))))  {
1556                     is_bad = TRUE;
1557                     DEBUG_L(PerlIO_printf(Perl_debug_log,
1558                                           "isalnum('%s') unexpectedly is %d\n",
1559                                           name, cBOOL(isalnum(i))));
1560                 }
1561                 if (UNLIKELY(cBOOL(isalpha(i)) != cBOOL(isALPHA_A(i))))  {
1562                     is_bad = TRUE;
1563                     DEBUG_L(PerlIO_printf(Perl_debug_log,
1564                                           "isalpha('%s') unexpectedly is %d\n",
1565                                           name, cBOOL(isalpha(i))));
1566                 }
1567                 if (UNLIKELY(cBOOL(isdigit(i)) != cBOOL(isDIGIT_A(i))))  {
1568                     is_bad = TRUE;
1569                     DEBUG_L(PerlIO_printf(Perl_debug_log,
1570                                           "isdigit('%s') unexpectedly is %d\n",
1571                                           name, cBOOL(isdigit(i))));
1572                 }
1573                 if (UNLIKELY(cBOOL(isgraph(i)) != cBOOL(isGRAPH_A(i))))  {
1574                     is_bad = TRUE;
1575                     DEBUG_L(PerlIO_printf(Perl_debug_log,
1576                                           "isgraph('%s') unexpectedly is %d\n",
1577                                           name, cBOOL(isgraph(i))));
1578                 }
1579                 if (UNLIKELY(cBOOL(islower(i)) != cBOOL(isLOWER_A(i))))  {
1580                     is_bad = TRUE;
1581                     DEBUG_L(PerlIO_printf(Perl_debug_log,
1582                                           "islower('%s') unexpectedly is %d\n",
1583                                           name, cBOOL(islower(i))));
1584                 }
1585                 if (UNLIKELY(cBOOL(isprint(i)) != cBOOL(isPRINT_A(i))))  {
1586                     is_bad = TRUE;
1587                     DEBUG_L(PerlIO_printf(Perl_debug_log,
1588                                           "isprint('%s') unexpectedly is %d\n",
1589                                           name, cBOOL(isprint(i))));
1590                 }
1591                 if (UNLIKELY(cBOOL(ispunct(i)) != cBOOL(isPUNCT_A(i))))  {
1592                     is_bad = TRUE;
1593                     DEBUG_L(PerlIO_printf(Perl_debug_log,
1594                                           "ispunct('%s') unexpectedly is %d\n",
1595                                           name, cBOOL(ispunct(i))));
1596                 }
1597                 if (UNLIKELY(cBOOL(isspace(i)) != cBOOL(isSPACE_A(i))))  {
1598                     is_bad = TRUE;
1599                     DEBUG_L(PerlIO_printf(Perl_debug_log,
1600                                           "isspace('%s') unexpectedly is %d\n",
1601                                           name, cBOOL(isspace(i))));
1602                 }
1603                 if (UNLIKELY(cBOOL(isupper(i)) != cBOOL(isUPPER_A(i))))  {
1604                     is_bad = TRUE;
1605                     DEBUG_L(PerlIO_printf(Perl_debug_log,
1606                                           "isupper('%s') unexpectedly is %d\n",
1607                                           name, cBOOL(isupper(i))));
1608                 }
1609                 if (UNLIKELY(cBOOL(isxdigit(i))!= cBOOL(isXDIGIT_A(i))))  {
1610                     is_bad = TRUE;
1611                     DEBUG_L(PerlIO_printf(Perl_debug_log,
1612                                           "isxdigit('%s') unexpectedly is %d\n",
1613                                           name, cBOOL(isxdigit(i))));
1614                 }
1615                 if (UNLIKELY(tolower(i) != (int) toLOWER_A(i))) {
1616                     is_bad = TRUE;
1617                     DEBUG_L(PerlIO_printf(Perl_debug_log,
1618                             "tolower('%s')=0x%x instead of the expected 0x%x\n",
1619                             name, tolower(i), (int) toLOWER_A(i)));
1620                 }
1621                 if (UNLIKELY(toupper(i) != (int) toUPPER_A(i))) {
1622                     is_bad = TRUE;
1623                     DEBUG_L(PerlIO_printf(Perl_debug_log,
1624                             "toupper('%s')=0x%x instead of the expected 0x%x\n",
1625                             name, toupper(i), (int) toUPPER_A(i)));
1626                 }
1627                 if (UNLIKELY((i == '\n' && ! isCNTRL_LC(i))))  {
1628                     is_bad = TRUE;
1629                     DEBUG_L(PerlIO_printf(Perl_debug_log,
1630                                 "'\\n' (=%02X) is not a control\n", (int) i));
1631                 }
1632 
1633                 /* Add to the list;  Separate multiple entries with a blank */
1634                 if (is_bad) {
1635                     if (bad_count) {
1636                         my_strlcat(bad_chars_list, " ", sizeof(bad_chars_list));
1637                     }
1638                     my_strlcat(bad_chars_list, name, sizeof(bad_chars_list));
1639                     bad_count++;
1640                 }
1641             }
1642         }
1643 
1644         if (bad_count == 2 && maybe_utf8_turkic) {
1645             bad_count = 0;
1646             *bad_chars_list = '\0';
1647             PL_fold_locale['I'] = 'I';
1648             PL_fold_locale['i'] = 'i';
1649             PL_in_utf8_turkic_locale = TRUE;
1650             DEBUG_L(PerlIO_printf(Perl_debug_log, "%s:%d: %s is turkic\n",
1651                                                  __FILE__, __LINE__, newctype));
1652         }
1653         else {
1654             PL_in_utf8_turkic_locale = FALSE;
1655         }
1656 
1657 #  ifdef MB_CUR_MAX
1658 
1659         /* We only handle single-byte locales (outside of UTF-8 ones; so if
1660          * this locale requires more than one byte, there are going to be
1661          * problems. */
1662         DEBUG_Lv(PerlIO_printf(Perl_debug_log,
1663                  "%s:%d: check_for_problems=%d, MB_CUR_MAX=%d\n",
1664                  __FILE__, __LINE__, check_for_problems, (int) MB_CUR_MAX));
1665 
1666         if (   check_for_problems && MB_CUR_MAX > 1
1667             && ! PL_in_utf8_CTYPE_locale
1668 
1669                /* Some platforms return MB_CUR_MAX > 1 for even the "C"
1670                 * locale.  Just assume that the implementation for them (plus
1671                 * for POSIX) is correct and the > 1 value is spurious.  (Since
1672                 * these are specially handled to never be considered UTF-8
1673                 * locales, as long as this is the only problem, everything
1674                 * should work fine */
1675             && strNE(newctype, "C") && strNE(newctype, "POSIX"))
1676         {
1677             multi_byte_locale = TRUE;
1678         }
1679 
1680 #  endif
1681 
1682         /* If we found problems and we want them output, do so */
1683         if (   (UNLIKELY(bad_count) || UNLIKELY(multi_byte_locale))
1684             && (LIKELY(ckWARN_d(WARN_LOCALE)) || UNLIKELY(DEBUG_L_TEST)))
1685         {
1686             if (UNLIKELY(bad_count) && PL_in_utf8_CTYPE_locale) {
1687                 PL_warn_locale = Perl_newSVpvf(aTHX_
1688                      "Locale '%s' contains (at least) the following characters"
1689                      " which have\nunexpected meanings: %s\nThe Perl program"
1690                      " will use the expected meanings",
1691                       newctype, bad_chars_list);
1692             }
1693             else {
1694                 PL_warn_locale = Perl_newSVpvf(aTHX_
1695                              "Locale '%s' may not work well.%s%s%s\n",
1696                              newctype,
1697                              (multi_byte_locale)
1698                               ? "  Some characters in it are not recognized by"
1699                                 " Perl."
1700                               : "",
1701                              (bad_count)
1702                               ? "\nThe following characters (and maybe others)"
1703                                 " may not have the same meaning as the Perl"
1704                                 " program expects:\n"
1705                               : "",
1706                              (bad_count)
1707                               ? bad_chars_list
1708                               : ""
1709                             );
1710             }
1711 
1712 #  ifdef HAS_NL_LANGINFO
1713 
1714             Perl_sv_catpvf(aTHX_ PL_warn_locale, "; codeset=%s",
1715                                     /* parameter FALSE is a don't care here */
1716                                     my_nl_langinfo(CODESET, FALSE));
1717 
1718 #  endif
1719 
1720             Perl_sv_catpvf(aTHX_ PL_warn_locale, "\n");
1721 
1722             /* If we are actually in the scope of the locale or are debugging,
1723              * output the message now.  If not in that scope, we save the
1724              * message to be output at the first operation using this locale,
1725              * if that actually happens.  Most programs don't use locales, so
1726              * they are immune to bad ones.  */
1727             if (IN_LC(LC_CTYPE) || UNLIKELY(DEBUG_L_TEST)) {
1728 
1729                 /* The '0' below suppresses a bogus gcc compiler warning */
1730                 Perl_warner(aTHX_ packWARN(WARN_LOCALE), SvPVX(PL_warn_locale), 0);
1731 
1732                 if (IN_LC(LC_CTYPE)) {
1733                     SvREFCNT_dec_NN(PL_warn_locale);
1734                     PL_warn_locale = NULL;
1735                 }
1736             }
1737         }
1738     }
1739 
1740 #endif /* USE_LOCALE_CTYPE */
1741 
1742 }
1743 
1744 void
1745 Perl__warn_problematic_locale()
1746 {
1747 
1748 #ifdef USE_LOCALE_CTYPE
1749 
1750     dTHX;
1751 
1752     /* Internal-to-core function that outputs the message in PL_warn_locale,
1753      * and then NULLS it.  Should be called only through the macro
1754      * _CHECK_AND_WARN_PROBLEMATIC_LOCALE */
1755 
1756     if (PL_warn_locale) {
1757         Perl_ck_warner(aTHX_ packWARN(WARN_LOCALE),
1758                              SvPVX(PL_warn_locale),
1759                              0 /* dummy to avoid compiler warning */ );
1760         SvREFCNT_dec_NN(PL_warn_locale);
1761         PL_warn_locale = NULL;
1762     }
1763 
1764 #endif
1765 
1766 }
1767 
1768 STATIC void
1769 S_new_collate(pTHX_ const char *newcoll)
1770 {
1771 
1772 #ifndef USE_LOCALE_COLLATE
1773 
1774     PERL_UNUSED_ARG(newcoll);
1775     PERL_UNUSED_CONTEXT;
1776 
1777 #else
1778 
1779     /* Called after each libc setlocale() call affecting LC_COLLATE, to tell
1780      * core Perl this and that 'newcoll' is the name of the new locale.
1781      *
1782      * The design of locale collation is that every locale change is given an
1783      * index 'PL_collation_ix'.  The first time a string particpates in an
1784      * operation that requires collation while locale collation is active, it
1785      * is given PERL_MAGIC_collxfrm magic (via sv_collxfrm_flags()).  That
1786      * magic includes the collation index, and the transformation of the string
1787      * by strxfrm(), q.v.  That transformation is used when doing comparisons,
1788      * instead of the string itself.  If a string changes, the magic is
1789      * cleared.  The next time the locale changes, the index is incremented,
1790      * and so we know during a comparison that the transformation is not
1791      * necessarily still valid, and so is recomputed.  Note that if the locale
1792      * changes enough times, the index could wrap (a U32), and it is possible
1793      * that a transformation would improperly be considered valid, leading to
1794      * an unlikely bug */
1795 
1796     if (! newcoll) {
1797         if (PL_collation_name) {
1798             ++PL_collation_ix;
1799             Safefree(PL_collation_name);
1800             PL_collation_name = NULL;
1801         }
1802         PL_collation_standard = TRUE;
1803       is_standard_collation:
1804         PL_collxfrm_base = 0;
1805         PL_collxfrm_mult = 2;
1806         PL_in_utf8_COLLATE_locale = FALSE;
1807         PL_strxfrm_NUL_replacement = '\0';
1808         PL_strxfrm_max_cp = 0;
1809         return;
1810     }
1811 
1812     /* If this is not the same locale as currently, set the new one up */
1813     if (! PL_collation_name || strNE(PL_collation_name, newcoll)) {
1814         ++PL_collation_ix;
1815         Safefree(PL_collation_name);
1816         PL_collation_name = stdize_locale(savepv(newcoll));
1817         PL_collation_standard = isNAME_C_OR_POSIX(newcoll);
1818         if (PL_collation_standard) {
1819             goto is_standard_collation;
1820         }
1821 
1822         PL_in_utf8_COLLATE_locale = _is_cur_LC_category_utf8(LC_COLLATE);
1823         PL_strxfrm_NUL_replacement = '\0';
1824         PL_strxfrm_max_cp = 0;
1825 
1826         /* A locale collation definition includes primary, secondary, tertiary,
1827          * etc. weights for each character.  To sort, the primary weights are
1828          * used, and only if they compare equal, then the secondary weights are
1829          * used, and only if they compare equal, then the tertiary, etc.
1830          *
1831          * strxfrm() works by taking the input string, say ABC, and creating an
1832          * output transformed string consisting of first the primary weights,
1833          * A¹B¹C¹ followed by the secondary ones, A²B²C²; and then the
1834          * tertiary, etc, yielding A¹B¹C¹ A²B²C² A³B³C³ ....  Some characters
1835          * may not have weights at every level.  In our example, let's say B
1836          * doesn't have a tertiary weight, and A doesn't have a secondary
1837          * weight.  The constructed string is then going to be
1838          *  A¹B¹C¹ B²C² A³C³ ....
1839          * This has the desired effect that strcmp() will look at the secondary
1840          * or tertiary weights only if the strings compare equal at all higher
1841          * priority weights.  The spaces shown here, like in
1842          *  "A¹B¹C¹ A²B²C² "
1843          * are not just for readability.  In the general case, these must
1844          * actually be bytes, which we will call here 'separator weights'; and
1845          * they must be smaller than any other weight value, but since these
1846          * are C strings, only the terminating one can be a NUL (some
1847          * implementations may include a non-NUL separator weight just before
1848          * the NUL).  Implementations tend to reserve 01 for the separator
1849          * weights.  They are needed so that a shorter string's secondary
1850          * weights won't be misconstrued as primary weights of a longer string,
1851          * etc.  By making them smaller than any other weight, the shorter
1852          * string will sort first.  (Actually, if all secondary weights are
1853          * smaller than all primary ones, there is no need for a separator
1854          * weight between those two levels, etc.)
1855          *
1856          * The length of the transformed string is roughly a linear function of
1857          * the input string.  It's not exactly linear because some characters
1858          * don't have weights at all levels.  When we call strxfrm() we have to
1859          * allocate some memory to hold the transformed string.  The
1860          * calculations below try to find coefficients 'm' and 'b' for this
1861          * locale so that m*x + b equals how much space we need, given the size
1862          * of the input string in 'x'.  If we calculate too small, we increase
1863          * the size as needed, and call strxfrm() again, but it is better to
1864          * get it right the first time to avoid wasted expensive string
1865          * transformations. */
1866 
1867         {
1868             /* We use the string below to find how long the tranformation of it
1869              * is.  Almost all locales are supersets of ASCII, or at least the
1870              * ASCII letters.  We use all of them, half upper half lower,
1871              * because if we used fewer, we might hit just the ones that are
1872              * outliers in a particular locale.  Most of the strings being
1873              * collated will contain a preponderance of letters, and even if
1874              * they are above-ASCII, they are likely to have the same number of
1875              * weight levels as the ASCII ones.  It turns out that digits tend
1876              * to have fewer levels, and some punctuation has more, but those
1877              * are relatively sparse in text, and khw believes this gives a
1878              * reasonable result, but it could be changed if experience so
1879              * dictates. */
1880             const char longer[] = "ABCDEFGHIJKLMnopqrstuvwxyz";
1881             char * x_longer;        /* Transformed 'longer' */
1882             Size_t x_len_longer;    /* Length of 'x_longer' */
1883 
1884             char * x_shorter;   /* We also transform a substring of 'longer' */
1885             Size_t x_len_shorter;
1886 
1887             /* _mem_collxfrm() is used get the transformation (though here we
1888              * are interested only in its length).  It is used because it has
1889              * the intelligence to handle all cases, but to work, it needs some
1890              * values of 'm' and 'b' to get it started.  For the purposes of
1891              * this calculation we use a very conservative estimate of 'm' and
1892              * 'b'.  This assumes a weight can be multiple bytes, enough to
1893              * hold any UV on the platform, and there are 5 levels, 4 weight
1894              * bytes, and a trailing NUL.  */
1895             PL_collxfrm_base = 5;
1896             PL_collxfrm_mult = 5 * sizeof(UV);
1897 
1898             /* Find out how long the transformation really is */
1899             x_longer = _mem_collxfrm(longer,
1900                                      sizeof(longer) - 1,
1901                                      &x_len_longer,
1902 
1903                                      /* We avoid converting to UTF-8 in the
1904                                       * called function by telling it the
1905                                       * string is in UTF-8 if the locale is a
1906                                       * UTF-8 one.  Since the string passed
1907                                       * here is invariant under UTF-8, we can
1908                                       * claim it's UTF-8 even though it isn't.
1909                                       * */
1910                                      PL_in_utf8_COLLATE_locale);
1911             Safefree(x_longer);
1912 
1913             /* Find out how long the transformation of a substring of 'longer'
1914              * is.  Together the lengths of these transformations are
1915              * sufficient to calculate 'm' and 'b'.  The substring is all of
1916              * 'longer' except the first character.  This minimizes the chances
1917              * of being swayed by outliers */
1918             x_shorter = _mem_collxfrm(longer + 1,
1919                                       sizeof(longer) - 2,
1920                                       &x_len_shorter,
1921                                       PL_in_utf8_COLLATE_locale);
1922             Safefree(x_shorter);
1923 
1924             /* If the results are nonsensical for this simple test, the whole
1925              * locale definition is suspect.  Mark it so that locale collation
1926              * is not active at all for it.  XXX Should we warn? */
1927             if (   x_len_shorter == 0
1928                 || x_len_longer == 0
1929                 || x_len_shorter >= x_len_longer)
1930             {
1931                 PL_collxfrm_mult = 0;
1932                 PL_collxfrm_base = 0;
1933             }
1934             else {
1935                 SSize_t base;       /* Temporary */
1936 
1937                 /* We have both:    m * strlen(longer)  + b = x_len_longer
1938                  *                  m * strlen(shorter) + b = x_len_shorter;
1939                  * subtracting yields:
1940                  *          m * (strlen(longer) - strlen(shorter))
1941                  *                             = x_len_longer - x_len_shorter
1942                  * But we have set things up so that 'shorter' is 1 byte smaller
1943                  * than 'longer'.  Hence:
1944                  *          m = x_len_longer - x_len_shorter
1945                  *
1946                  * But if something went wrong, make sure the multiplier is at
1947                  * least 1.
1948                  */
1949                 if (x_len_longer > x_len_shorter) {
1950                     PL_collxfrm_mult = (STRLEN) x_len_longer - x_len_shorter;
1951                 }
1952                 else {
1953                     PL_collxfrm_mult = 1;
1954                 }
1955 
1956                 /*     mx + b = len
1957                  * so:      b = len - mx
1958                  * but in case something has gone wrong, make sure it is
1959                  * non-negative */
1960                 base = x_len_longer - PL_collxfrm_mult * (sizeof(longer) - 1);
1961                 if (base < 0) {
1962                     base = 0;
1963                 }
1964 
1965                 /* Add 1 for the trailing NUL */
1966                 PL_collxfrm_base = base + 1;
1967             }
1968 
1969 #  ifdef DEBUGGING
1970 
1971             if (DEBUG_L_TEST || debug_initialization) {
1972                 PerlIO_printf(Perl_debug_log,
1973                     "%s:%d: ?UTF-8 locale=%d; x_len_shorter=%zu, "
1974                     "x_len_longer=%zu,"
1975                     " collate multipler=%zu, collate base=%zu\n",
1976                     __FILE__, __LINE__,
1977                     PL_in_utf8_COLLATE_locale,
1978                     x_len_shorter, x_len_longer,
1979                     PL_collxfrm_mult, PL_collxfrm_base);
1980             }
1981 #  endif
1982 
1983         }
1984     }
1985 
1986 #endif /* USE_LOCALE_COLLATE */
1987 
1988 }
1989 
1990 #endif
1991 
1992 #ifdef WIN32
1993 
1994 #define USE_WSETLOCALE
1995 
1996 #ifdef USE_WSETLOCALE
1997 
1998 STATIC char *
1999 S_wrap_wsetlocale(pTHX_ int category, const char *locale) {
2000     wchar_t *wlocale;
2001     wchar_t *wresult;
2002     char *result;
2003 
2004     if (locale) {
2005         int req_size =
2006             MultiByteToWideChar(CP_UTF8, 0, locale, -1, NULL, 0);
2007 
2008         if (!req_size) {
2009             errno = EINVAL;
2010             return NULL;
2011         }
2012 
2013         Newx(wlocale, req_size, wchar_t);
2014         if (!MultiByteToWideChar(CP_UTF8, 0, locale, -1, wlocale, req_size)) {
2015             Safefree(wlocale);
2016             errno = EINVAL;
2017             return NULL;
2018         }
2019     }
2020     else {
2021         wlocale = NULL;
2022     }
2023     wresult = _wsetlocale(category, wlocale);
2024     Safefree(wlocale);
2025     if (wresult) {
2026         int req_size =
2027             WideCharToMultiByte(CP_UTF8, 0, wresult, -1, NULL, 0, NULL, NULL);
2028         Newx(result, req_size, char);
2029         SAVEFREEPV(result); /* is there something better we can do here? */
2030         if (!WideCharToMultiByte(CP_UTF8, 0, wresult, -1,
2031                                  result, req_size, NULL, NULL)) {
2032             errno = EINVAL;
2033             return NULL;
2034         }
2035     }
2036     else {
2037         result = NULL;
2038     }
2039 
2040     return result;
2041 }
2042 
2043 #endif
2044 
2045 STATIC char *
2046 S_win32_setlocale(pTHX_ int category, const char* locale)
2047 {
2048     /* This, for Windows, emulates POSIX setlocale() behavior.  There is no
2049      * difference between the two unless the input locale is "", which normally
2050      * means on Windows to get the machine default, which is set via the
2051      * computer's "Regional and Language Options" (or its current equivalent).
2052      * In POSIX, it instead means to find the locale from the user's
2053      * environment.  This routine changes the Windows behavior to first look in
2054      * the environment, and, if anything is found, use that instead of going to
2055      * the machine default.  If there is no environment override, the machine
2056      * default is used, by calling the real setlocale() with "".
2057      *
2058      * The POSIX behavior is to use the LC_ALL variable if set; otherwise to
2059      * use the particular category's variable if set; otherwise to use the LANG
2060      * variable. */
2061 
2062     bool override_LC_ALL = FALSE;
2063     char * result;
2064     unsigned int i;
2065 
2066     if (locale && strEQ(locale, "")) {
2067 
2068 #  ifdef LC_ALL
2069 
2070         locale = PerlEnv_getenv("LC_ALL");
2071         if (! locale) {
2072             if (category ==  LC_ALL) {
2073                 override_LC_ALL = TRUE;
2074             }
2075             else {
2076 
2077 #  endif
2078 
2079                 for (i = 0; i < NOMINAL_LC_ALL_INDEX; i++) {
2080                     if (category == categories[i]) {
2081                         locale = PerlEnv_getenv(category_names[i]);
2082                         goto found_locale;
2083                     }
2084                 }
2085 
2086                 locale = PerlEnv_getenv("LANG");
2087                 if (! locale) {
2088                     locale = "";
2089                 }
2090 
2091               found_locale: ;
2092 
2093 #  ifdef LC_ALL
2094 
2095             }
2096         }
2097 
2098 #  endif
2099 
2100     }
2101 
2102 #ifdef USE_WSETLOCALE
2103     result = S_wrap_wsetlocale(aTHX_ category, locale);
2104 #else
2105     result = setlocale(category, locale);
2106 #endif
2107     DEBUG_L(STMT_START {
2108                 dSAVE_ERRNO;
2109                 PerlIO_printf(Perl_debug_log, "%s:%d: %s\n", __FILE__, __LINE__,
2110                             setlocale_debug_string(category, locale, result));
2111                 RESTORE_ERRNO;
2112             } STMT_END);
2113 
2114     if (! override_LC_ALL)  {
2115         return result;
2116     }
2117 
2118     /* Here the input category was LC_ALL, and we have set it to what is in the
2119      * LANG variable or the system default if there is no LANG.  But these have
2120      * lower priority than the other LC_foo variables, so override it for each
2121      * one that is set.  (If they are set to "", it means to use the same thing
2122      * we just set LC_ALL to, so can skip) */
2123 
2124     for (i = 0; i < LC_ALL_INDEX; i++) {
2125         result = PerlEnv_getenv(category_names[i]);
2126         if (result && strNE(result, "")) {
2127 #ifdef USE_WSETLOCALE
2128             S_wrap_wsetlocale(aTHX_ categories[i], result);
2129 #else
2130             setlocale(categories[i], result);
2131 #endif
2132             DEBUG_Lv(PerlIO_printf(Perl_debug_log, "%s:%d: %s\n",
2133                 __FILE__, __LINE__,
2134                 setlocale_debug_string(categories[i], result, "not captured")));
2135         }
2136     }
2137 
2138     result = setlocale(LC_ALL, NULL);
2139     DEBUG_L(STMT_START {
2140                 dSAVE_ERRNO;
2141                 PerlIO_printf(Perl_debug_log, "%s:%d: %s\n",
2142                                __FILE__, __LINE__,
2143                                setlocale_debug_string(LC_ALL, NULL, result));
2144                 RESTORE_ERRNO;
2145             } STMT_END);
2146 
2147     return result;
2148 }
2149 
2150 #endif
2151 
2152 /*
2153 =for apidoc Perl_setlocale
2154 
2155 This is an (almost) drop-in replacement for the system L<C<setlocale(3)>>,
2156 taking the same parameters, and returning the same information, except that it
2157 returns the correct underlying C<LC_NUMERIC> locale.  Regular C<setlocale> will
2158 instead return C<C> if the underlying locale has a non-dot decimal point
2159 character, or a non-empty thousands separator for displaying floating point
2160 numbers.  This is because perl keeps that locale category such that it has a
2161 dot and empty separator, changing the locale briefly during the operations
2162 where the underlying one is required. C<Perl_setlocale> knows about this, and
2163 compensates; regular C<setlocale> doesn't.
2164 
2165 Another reason it isn't completely a drop-in replacement is that it is
2166 declared to return S<C<const char *>>, whereas the system setlocale omits the
2167 C<const> (presumably because its API was specified long ago, and can't be
2168 updated; it is illegal to change the information C<setlocale> returns; doing
2169 so leads to segfaults.)
2170 
2171 Finally, C<Perl_setlocale> works under all circumstances, whereas plain
2172 C<setlocale> can be completely ineffective on some platforms under some
2173 configurations.
2174 
2175 C<Perl_setlocale> should not be used to change the locale except on systems
2176 where the predefined variable C<${^SAFE_LOCALES}> is 1.  On some such systems,
2177 the system C<setlocale()> is ineffective, returning the wrong information, and
2178 failing to actually change the locale.  C<Perl_setlocale>, however works
2179 properly in all circumstances.
2180 
2181 The return points to a per-thread static buffer, which is overwritten the next
2182 time C<Perl_setlocale> is called from the same thread.
2183 
2184 =cut
2185 
2186 */
2187 
2188 const char *
2189 Perl_setlocale(const int category, const char * locale)
2190 {
2191     /* This wraps POSIX::setlocale() */
2192 
2193 #ifndef USE_LOCALE
2194 
2195     PERL_UNUSED_ARG(category);
2196     PERL_UNUSED_ARG(locale);
2197 
2198     return "C";
2199 
2200 #else
2201 
2202     const char * retval;
2203     const char * newlocale;
2204     dSAVEDERRNO;
2205     dTHX;
2206     DECLARATION_FOR_LC_NUMERIC_MANIPULATION;
2207 
2208 #ifdef USE_LOCALE_NUMERIC
2209 
2210     /* A NULL locale means only query what the current one is.  We have the
2211      * LC_NUMERIC name saved, because we are normally switched into the C
2212      * (or equivalent) locale for it.  For an LC_ALL query, switch back to get
2213      * the correct results.  All other categories don't require special
2214      * handling */
2215     if (locale == NULL) {
2216         if (category == LC_NUMERIC) {
2217 
2218             /* We don't have to copy this return value, as it is a per-thread
2219              * variable, and won't change until a future setlocale */
2220             return PL_numeric_name;
2221         }
2222 
2223 #  ifdef LC_ALL
2224 
2225         else if (category == LC_ALL) {
2226             STORE_LC_NUMERIC_FORCE_TO_UNDERLYING();
2227         }
2228 
2229 #  endif
2230 
2231     }
2232 
2233 #endif
2234 
2235     retval = save_to_buffer(do_setlocale_r(category, locale),
2236                             &PL_setlocale_buf, &PL_setlocale_bufsize, 0);
2237     SAVE_ERRNO;
2238 
2239 #if defined(USE_LOCALE_NUMERIC) && defined(LC_ALL)
2240 
2241     if (locale == NULL && category == LC_ALL) {
2242         RESTORE_LC_NUMERIC();
2243     }
2244 
2245 #endif
2246 
2247     DEBUG_L(PerlIO_printf(Perl_debug_log,
2248         "%s:%d: %s\n", __FILE__, __LINE__,
2249             setlocale_debug_string(category, locale, retval)));
2250 
2251     RESTORE_ERRNO;
2252 
2253     if (! retval) {
2254         return NULL;
2255     }
2256 
2257     /* If locale == NULL, we are just querying the state */
2258     if (locale == NULL) {
2259         return retval;
2260     }
2261 
2262     /* Now that have switched locales, we have to update our records to
2263      * correspond. */
2264 
2265     switch (category) {
2266 
2267 #ifdef USE_LOCALE_CTYPE
2268 
2269         case LC_CTYPE:
2270             new_ctype(retval);
2271             break;
2272 
2273 #endif
2274 #ifdef USE_LOCALE_COLLATE
2275 
2276         case LC_COLLATE:
2277             new_collate(retval);
2278             break;
2279 
2280 #endif
2281 #ifdef USE_LOCALE_NUMERIC
2282 
2283         case LC_NUMERIC:
2284             new_numeric(retval);
2285             break;
2286 
2287 #endif
2288 #ifdef LC_ALL
2289 
2290         case LC_ALL:
2291 
2292             /* LC_ALL updates all the things we care about.  The values may not
2293              * be the same as 'retval', as the locale "" may have set things
2294              * individually */
2295 
2296 #  ifdef USE_LOCALE_CTYPE
2297 
2298             newlocale = savepv(do_setlocale_c(LC_CTYPE, NULL));
2299             new_ctype(newlocale);
2300             Safefree(newlocale);
2301 
2302 #  endif /* USE_LOCALE_CTYPE */
2303 #  ifdef USE_LOCALE_COLLATE
2304 
2305             newlocale = savepv(do_setlocale_c(LC_COLLATE, NULL));
2306             new_collate(newlocale);
2307             Safefree(newlocale);
2308 
2309 #  endif
2310 #  ifdef USE_LOCALE_NUMERIC
2311 
2312             newlocale = savepv(do_setlocale_c(LC_NUMERIC, NULL));
2313             new_numeric(newlocale);
2314             Safefree(newlocale);
2315 
2316 #  endif /* USE_LOCALE_NUMERIC */
2317 #endif /* LC_ALL */
2318 
2319         default:
2320             break;
2321     }
2322 
2323     return retval;
2324 
2325 #endif
2326 
2327 }
2328 
2329 PERL_STATIC_INLINE const char *
2330 S_save_to_buffer(const char * string, char **buf, Size_t *buf_size, const Size_t offset)
2331 {
2332     /* Copy the NUL-terminated 'string' to 'buf' + 'offset'.  'buf' has size 'buf_size',
2333      * growing it if necessary */
2334 
2335     Size_t string_size;
2336 
2337     PERL_ARGS_ASSERT_SAVE_TO_BUFFER;
2338 
2339     if (! string) {
2340         return NULL;
2341     }
2342 
2343     string_size = strlen(string) + offset + 1;
2344 
2345     if (*buf_size == 0) {
2346         Newx(*buf, string_size, char);
2347         *buf_size = string_size;
2348     }
2349     else if (string_size > *buf_size) {
2350         Renew(*buf, string_size, char);
2351         *buf_size = string_size;
2352     }
2353 
2354     Copy(string, *buf + offset, string_size - offset, char);
2355     return *buf;
2356 }
2357 
2358 /*
2359 
2360 =for apidoc Perl_langinfo
2361 
2362 This is an (almost) drop-in replacement for the system C<L<nl_langinfo(3)>>,
2363 taking the same C<item> parameter values, and returning the same information.
2364 But it is more thread-safe than regular C<nl_langinfo()>, and hides the quirks
2365 of Perl's locale handling from your code, and can be used on systems that lack
2366 a native C<nl_langinfo>.
2367 
2368 Expanding on these:
2369 
2370 =over
2371 
2372 =item *
2373 
2374 The reason it isn't quite a drop-in replacement is actually an advantage.  The
2375 only difference is that it returns S<C<const char *>>, whereas plain
2376 C<nl_langinfo()> returns S<C<char *>>, but you are (only by documentation)
2377 forbidden to write into the buffer.  By declaring this C<const>, the compiler
2378 enforces this restriction, so if it is violated, you know at compilation time,
2379 rather than getting segfaults at runtime.
2380 
2381 =item *
2382 
2383 It delivers the correct results for the C<RADIXCHAR> and C<THOUSEP> items,
2384 without you having to write extra code.  The reason for the extra code would be
2385 because these are from the C<LC_NUMERIC> locale category, which is normally
2386 kept set by Perl so that the radix is a dot, and the separator is the empty
2387 string, no matter what the underlying locale is supposed to be, and so to get
2388 the expected results, you have to temporarily toggle into the underlying
2389 locale, and later toggle back.  (You could use plain C<nl_langinfo> and
2390 C<L</STORE_LC_NUMERIC_FORCE_TO_UNDERLYING>> for this but then you wouldn't get
2391 the other advantages of C<Perl_langinfo()>; not keeping C<LC_NUMERIC> in the C
2392 (or equivalent) locale would break a lot of CPAN, which is expecting the radix
2393 (decimal point) character to be a dot.)
2394 
2395 =item *
2396 
2397 The system function it replaces can have its static return buffer trashed,
2398 not only by a subsequent call to that function, but by a C<freelocale>,
2399 C<setlocale>, or other locale change.  The returned buffer of this function is
2400 not changed until the next call to it, so the buffer is never in a trashed
2401 state.
2402 
2403 =item *
2404 
2405 Its return buffer is per-thread, so it also is never overwritten by a call to
2406 this function from another thread;  unlike the function it replaces.
2407 
2408 =item *
2409 
2410 But most importantly, it works on systems that don't have C<nl_langinfo>, such
2411 as Windows, hence makes your code more portable.  Of the fifty-some possible
2412 items specified by the POSIX 2008 standard,
2413 L<http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/langinfo.h.html>,
2414 only one is completely unimplemented, though on non-Windows platforms, another
2415 significant one is also not implemented).  It uses various techniques to
2416 recover the other items, including calling C<L<localeconv(3)>>, and
2417 C<L<strftime(3)>>, both of which are specified in C89, so should be always be
2418 available.  Later C<strftime()> versions have additional capabilities; C<""> is
2419 returned for those not available on your system.
2420 
2421 It is important to note that when called with an item that is recovered by
2422 using C<localeconv>, the buffer from any previous explicit call to
2423 C<localeconv> will be overwritten.  This means you must save that buffer's
2424 contents if you need to access them after a call to this function.  (But note
2425 that you might not want to be using C<localeconv()> directly anyway, because of
2426 issues like the ones listed in the second item of this list (above) for
2427 C<RADIXCHAR> and C<THOUSEP>.  You can use the methods given in L<perlcall> to
2428 call L<POSIX/localeconv> and avoid all the issues, but then you have a hash to
2429 unpack).
2430 
2431 The details for those items which may deviate from what this emulation returns
2432 and what a native C<nl_langinfo()> would return are specified in
2433 L<I18N::Langinfo>.
2434 
2435 =back
2436 
2437 When using C<Perl_langinfo> on systems that don't have a native
2438 C<nl_langinfo()>, you must
2439 
2440  #include "perl_langinfo.h"
2441 
2442 before the C<perl.h> C<#include>.  You can replace your C<langinfo.h>
2443 C<#include> with this one.  (Doing it this way keeps out the symbols that plain
2444 C<langinfo.h> would try to import into the namespace for code that doesn't need
2445 it.)
2446 
2447 The original impetus for C<Perl_langinfo()> was so that code that needs to
2448 find out the current currency symbol, floating point radix character, or digit
2449 grouping separator can use, on all systems, the simpler and more
2450 thread-friendly C<nl_langinfo> API instead of C<L<localeconv(3)>> which is a
2451 pain to make thread-friendly.  For other fields returned by C<localeconv>, it
2452 is better to use the methods given in L<perlcall> to call
2453 L<C<POSIX::localeconv()>|POSIX/localeconv>, which is thread-friendly.
2454 
2455 =cut
2456 
2457 */
2458 
2459 const char *
2460 #ifdef HAS_NL_LANGINFO
2461 Perl_langinfo(const nl_item item)
2462 #else
2463 Perl_langinfo(const int item)
2464 #endif
2465 {
2466     return my_nl_langinfo(item, TRUE);
2467 }
2468 
2469 STATIC const char *
2470 #ifdef HAS_NL_LANGINFO
2471 S_my_nl_langinfo(const nl_item item, bool toggle)
2472 #else
2473 S_my_nl_langinfo(const int item, bool toggle)
2474 #endif
2475 {
2476     dTHX;
2477     const char * retval;
2478 
2479 #ifdef USE_LOCALE_NUMERIC
2480 
2481     /* We only need to toggle into the underlying LC_NUMERIC locale for these
2482      * two items, and only if not already there */
2483     if (toggle && ((   item != RADIXCHAR && item != THOUSEP)
2484                     || PL_numeric_underlying))
2485 
2486 #endif  /* No toggling needed if not using LC_NUMERIC */
2487 
2488         toggle = FALSE;
2489 
2490 #if defined(HAS_NL_LANGINFO) /* nl_langinfo() is available.  */
2491 #  if   ! defined(HAS_THREAD_SAFE_NL_LANGINFO_L)      \
2492      || ! defined(HAS_POSIX_2008_LOCALE)
2493 
2494     /* Here, use plain nl_langinfo(), switching to the underlying LC_NUMERIC
2495      * for those items dependent on it.  This must be copied to a buffer before
2496      * switching back, as some systems destroy the buffer when setlocale() is
2497      * called */
2498 
2499     {
2500         DECLARATION_FOR_LC_NUMERIC_MANIPULATION;
2501 
2502         if (toggle) {
2503             STORE_LC_NUMERIC_FORCE_TO_UNDERLYING();
2504         }
2505 
2506         /* Prevent interference from another thread executing this code
2507          * section. */
2508         NL_LANGINFO_LOCK;
2509 
2510         /* Copy to a per-thread buffer, which is also one that won't be
2511          * destroyed by a subsequent setlocale(), such as the
2512          * RESTORE_LC_NUMERIC may do just below. */
2513         retval = save_to_buffer(nl_langinfo(item),
2514                                 &PL_langinfo_buf, &PL_langinfo_bufsize, 0);
2515         NL_LANGINFO_UNLOCK;
2516 
2517         if (toggle) {
2518             RESTORE_LC_NUMERIC();
2519         }
2520     }
2521 
2522 #  else /* Use nl_langinfo_l(), avoiding both a mutex and changing the locale */
2523 
2524     {
2525         bool do_free = FALSE;
2526         locale_t cur = uselocale((locale_t) 0);
2527 
2528         if (cur == LC_GLOBAL_LOCALE) {
2529             cur = duplocale(LC_GLOBAL_LOCALE);
2530             do_free = TRUE;
2531         }
2532 
2533 #    ifdef USE_LOCALE_NUMERIC
2534 
2535         if (toggle) {
2536             if (PL_underlying_numeric_obj) {
2537                 cur = PL_underlying_numeric_obj;
2538             }
2539             else {
2540                 cur = newlocale(LC_NUMERIC_MASK, PL_numeric_name, cur);
2541                 do_free = TRUE;
2542             }
2543         }
2544 
2545 #    endif
2546 
2547         /* We have to save it to a buffer, because the freelocale() just below
2548          * can invalidate the internal one */
2549         retval = save_to_buffer(nl_langinfo_l(item, cur),
2550                                 &PL_langinfo_buf, &PL_langinfo_bufsize, 0);
2551 
2552         if (do_free) {
2553             freelocale(cur);
2554         }
2555     }
2556 
2557 #  endif
2558 
2559     if (strEQ(retval, "")) {
2560         if (item == YESSTR) {
2561             return "yes";
2562         }
2563         if (item == NOSTR) {
2564             return "no";
2565         }
2566     }
2567 
2568     return retval;
2569 
2570 #else   /* Below, emulate nl_langinfo as best we can */
2571 
2572     {
2573 
2574 #  ifdef HAS_LOCALECONV
2575 
2576         const struct lconv* lc;
2577         const char * temp;
2578         DECLARATION_FOR_LC_NUMERIC_MANIPULATION;
2579 
2580 #    ifdef TS_W32_BROKEN_LOCALECONV
2581 
2582         const char * save_global;
2583         const char * save_thread;
2584         int needed_size;
2585         char * ptr;
2586         char * e;
2587         char * item_start;
2588 
2589 #    endif
2590 #  endif
2591 #  ifdef HAS_STRFTIME
2592 
2593         struct tm tm;
2594         bool return_format = FALSE; /* Return the %format, not the value */
2595         const char * format;
2596 
2597 #  endif
2598 
2599         /* We copy the results to a per-thread buffer, even if not
2600          * multi-threaded.  This is in part to simplify this code, and partly
2601          * because we need a buffer anyway for strftime(), and partly because a
2602          * call of localeconv() could otherwise wipe out the buffer, and the
2603          * programmer would not be expecting this, as this is a nl_langinfo()
2604          * substitute after all, so s/he might be thinking their localeconv()
2605          * is safe until another localeconv() call. */
2606 
2607         switch (item) {
2608             Size_t len;
2609 
2610             /* This is unimplemented */
2611             case ERA:      /* For use with strftime() %E modifier */
2612 
2613             default:
2614                 return "";
2615 
2616             /* We use only an English set, since we don't know any more */
2617             case YESEXPR:   return "^[+1yY]";
2618             case YESSTR:    return "yes";
2619             case NOEXPR:    return "^[-0nN]";
2620             case NOSTR:     return "no";
2621 
2622             case CODESET:
2623 
2624 #  ifndef WIN32
2625 
2626                 /* On non-windows, this is unimplemented, in part because of
2627                  * inconsistencies between vendors.  The Darwin native
2628                  * nl_langinfo() implementation simply looks at everything past
2629                  * any dot in the name, but that doesn't work for other
2630                  * vendors.  Many Linux locales that don't have UTF-8 in their
2631                  * names really are UTF-8, for example; z/OS locales that do
2632                  * have UTF-8 in their names, aren't really UTF-8 */
2633                 return "";
2634 
2635 #  else
2636 
2637                 {   /* But on Windows, the name does seem to be consistent, so
2638                        use that. */
2639                     const char * p;
2640                     const char * first;
2641                     Size_t offset = 0;
2642                     const char * name = my_setlocale(LC_CTYPE, NULL);
2643 
2644                     if (isNAME_C_OR_POSIX(name)) {
2645                         return "ANSI_X3.4-1968";
2646                     }
2647 
2648                     /* Find the dot in the locale name */
2649                     first = (const char *) strchr(name, '.');
2650                     if (! first) {
2651                         first = name;
2652                         goto has_nondigit;
2653                     }
2654 
2655                     /* Look at everything past the dot */
2656                     first++;
2657                     p = first;
2658 
2659                     while (*p) {
2660                         if (! isDIGIT(*p)) {
2661                             goto has_nondigit;
2662                         }
2663 
2664                         p++;
2665                     }
2666 
2667                     /* Here everything past the dot is a digit.  Treat it as a
2668                      * code page */
2669                     retval = save_to_buffer("CP", &PL_langinfo_buf,
2670                                                 &PL_langinfo_bufsize, 0);
2671                     offset = STRLENs("CP");
2672 
2673                   has_nondigit:
2674 
2675                     retval = save_to_buffer(first, &PL_langinfo_buf,
2676                                             &PL_langinfo_bufsize, offset);
2677                 }
2678 
2679                 break;
2680 
2681 #  endif
2682 #  ifdef HAS_LOCALECONV
2683 
2684             case CRNCYSTR:
2685 
2686                 /* We don't bother with localeconv_l() because any system that
2687                  * has it is likely to also have nl_langinfo() */
2688 
2689                 LOCALECONV_LOCK;    /* Prevent interference with other threads
2690                                        using localeconv() */
2691 
2692 #    ifdef TS_W32_BROKEN_LOCALECONV
2693 
2694                 /* This is a workaround for a Windows bug prior to VS 15.
2695                  * What we do here is, while locked, switch to the global
2696                  * locale so localeconv() works; then switch back just before
2697                  * the unlock.  This can screw things up if some thread is
2698                  * already using the global locale while assuming no other is.
2699                  * A different workaround would be to call GetCurrencyFormat on
2700                  * a known value, and parse it; patches welcome
2701                  *
2702                  * We have to use LC_ALL instead of LC_MONETARY because of
2703                  * another bug in Windows */
2704 
2705                 save_thread = savepv(my_setlocale(LC_ALL, NULL));
2706                 _configthreadlocale(_DISABLE_PER_THREAD_LOCALE);
2707                 save_global= savepv(my_setlocale(LC_ALL, NULL));
2708                 my_setlocale(LC_ALL, save_thread);
2709 
2710 #    endif
2711 
2712                 lc = localeconv();
2713                 if (   ! lc
2714                     || ! lc->currency_symbol
2715                     || strEQ("", lc->currency_symbol))
2716                 {
2717                     LOCALECONV_UNLOCK;
2718                     return "";
2719                 }
2720 
2721                 /* Leave the first spot empty to be filled in below */
2722                 retval = save_to_buffer(lc->currency_symbol, &PL_langinfo_buf,
2723                                         &PL_langinfo_bufsize, 1);
2724                 if (lc->mon_decimal_point && strEQ(lc->mon_decimal_point, ""))
2725                 { /*  khw couldn't figure out how the localedef specifications
2726                       would show that the $ should replace the radix; this is
2727                       just a guess as to how it might work.*/
2728                     PL_langinfo_buf[0] = '.';
2729                 }
2730                 else if (lc->p_cs_precedes) {
2731                     PL_langinfo_buf[0] = '-';
2732                 }
2733                 else {
2734                     PL_langinfo_buf[0] = '+';
2735                 }
2736 
2737 #    ifdef TS_W32_BROKEN_LOCALECONV
2738 
2739                 my_setlocale(LC_ALL, save_global);
2740                 _configthreadlocale(_ENABLE_PER_THREAD_LOCALE);
2741                 my_setlocale(LC_ALL, save_thread);
2742                 Safefree(save_global);
2743                 Safefree(save_thread);
2744 
2745 #    endif
2746 
2747                 LOCALECONV_UNLOCK;
2748                 break;
2749 
2750 #    ifdef TS_W32_BROKEN_LOCALECONV
2751 
2752             case RADIXCHAR:
2753 
2754                 /* For this, we output a known simple floating point number to
2755                  * a buffer, and parse it, looking for the radix */
2756 
2757                 if (toggle) {
2758                     STORE_LC_NUMERIC_FORCE_TO_UNDERLYING();
2759                 }
2760 
2761                 if (PL_langinfo_bufsize < 10) {
2762                     PL_langinfo_bufsize = 10;
2763                     Renew(PL_langinfo_buf, PL_langinfo_bufsize, char);
2764                 }
2765 
2766                 needed_size = my_snprintf(PL_langinfo_buf, PL_langinfo_bufsize,
2767                                           "%.1f", 1.5);
2768                 if (needed_size >= (int) PL_langinfo_bufsize) {
2769                     PL_langinfo_bufsize = needed_size + 1;
2770                     Renew(PL_langinfo_buf, PL_langinfo_bufsize, char);
2771                     needed_size = my_snprintf(PL_langinfo_buf, PL_langinfo_bufsize,
2772                                              "%.1f", 1.5);
2773                     assert(needed_size < (int) PL_langinfo_bufsize);
2774                 }
2775 
2776                 ptr = PL_langinfo_buf;
2777                 e = PL_langinfo_buf + PL_langinfo_bufsize;
2778 
2779                 /* Find the '1' */
2780                 while (ptr < e && *ptr != '1') {
2781                     ptr++;
2782                 }
2783                 ptr++;
2784 
2785                 /* Find the '5' */
2786                 item_start = ptr;
2787                 while (ptr < e && *ptr != '5') {
2788                     ptr++;
2789                 }
2790 
2791                 /* Everything in between is the radix string */
2792                 if (ptr >= e) {
2793                     PL_langinfo_buf[0] = '?';
2794                     PL_langinfo_buf[1] = '\0';
2795                 }
2796                 else {
2797                     *ptr = '\0';
2798                     Move(item_start, PL_langinfo_buf, ptr - PL_langinfo_buf, char);
2799                 }
2800 
2801                 if (toggle) {
2802                     RESTORE_LC_NUMERIC();
2803                 }
2804 
2805                 retval = PL_langinfo_buf;
2806                 break;
2807 
2808 #    else
2809 
2810             case RADIXCHAR:     /* No special handling needed */
2811 
2812 #    endif
2813 
2814             case THOUSEP:
2815 
2816                 if (toggle) {
2817                     STORE_LC_NUMERIC_FORCE_TO_UNDERLYING();
2818                 }
2819 
2820                 LOCALECONV_LOCK;    /* Prevent interference with other threads
2821                                        using localeconv() */
2822 
2823 #    ifdef TS_W32_BROKEN_LOCALECONV
2824 
2825                 /* This should only be for the thousands separator.  A
2826                  * different work around would be to use GetNumberFormat on a
2827                  * known value and parse the result to find the separator */
2828                 save_thread = savepv(my_setlocale(LC_ALL, NULL));
2829                 _configthreadlocale(_DISABLE_PER_THREAD_LOCALE);
2830                 save_global = savepv(my_setlocale(LC_ALL, NULL));
2831                 my_setlocale(LC_ALL, save_thread);
2832 #      if 0
2833                 /* This is the start of code that for broken Windows replaces
2834                  * the above and below code, and instead calls
2835                  * GetNumberFormat() and then would parse that to find the
2836                  * thousands separator.  It needs to handle UTF-16 vs -8
2837                  * issues. */
2838 
2839                 needed_size = GetNumberFormatEx(PL_numeric_name, 0, "1234.5", NULL, PL_langinfo_buf, PL_langinfo_bufsize);
2840                 DEBUG_L(PerlIO_printf(Perl_debug_log,
2841                     "%s: %d: return from GetNumber, count=%d, val=%s\n",
2842                     __FILE__, __LINE__, needed_size, PL_langinfo_buf));
2843 
2844 #      endif
2845 #    endif
2846 
2847                 lc = localeconv();
2848                 if (! lc) {
2849                     temp = "";
2850                 }
2851                 else {
2852                     temp = (item == RADIXCHAR)
2853                              ? lc->decimal_point
2854                              : lc->thousands_sep;
2855                     if (! temp) {
2856                         temp = "";
2857                     }
2858                 }
2859 
2860                 retval = save_to_buffer(temp, &PL_langinfo_buf,
2861                                         &PL_langinfo_bufsize, 0);
2862 
2863 #    ifdef TS_W32_BROKEN_LOCALECONV
2864 
2865                 my_setlocale(LC_ALL, save_global);
2866                 _configthreadlocale(_ENABLE_PER_THREAD_LOCALE);
2867                 my_setlocale(LC_ALL, save_thread);
2868                 Safefree(save_global);
2869                 Safefree(save_thread);
2870 
2871 #    endif
2872 
2873                 LOCALECONV_UNLOCK;
2874 
2875                 if (toggle) {
2876                     RESTORE_LC_NUMERIC();
2877                 }
2878 
2879                 break;
2880 
2881 #  endif
2882 #  ifdef HAS_STRFTIME
2883 
2884             /* These are defined by C89, so we assume that strftime supports
2885              * them, and so are returned unconditionally; they may not be what
2886              * the locale actually says, but should give good enough results
2887              * for someone using them as formats (as opposed to trying to parse
2888              * them to figure out what the locale says).  The other format
2889              * items are actually tested to verify they work on the platform */
2890             case D_FMT:         return "%x";
2891             case T_FMT:         return "%X";
2892             case D_T_FMT:       return "%c";
2893 
2894             /* These formats are only available in later strfmtime's */
2895             case ERA_D_FMT: case ERA_T_FMT: case ERA_D_T_FMT: case T_FMT_AMPM:
2896 
2897             /* The rest can be gotten from most versions of strftime(). */
2898             case ABDAY_1: case ABDAY_2: case ABDAY_3:
2899             case ABDAY_4: case ABDAY_5: case ABDAY_6: case ABDAY_7:
2900             case ALT_DIGITS:
2901             case AM_STR: case PM_STR:
2902             case ABMON_1: case ABMON_2: case ABMON_3: case ABMON_4:
2903             case ABMON_5: case ABMON_6: case ABMON_7: case ABMON_8:
2904             case ABMON_9: case ABMON_10: case ABMON_11: case ABMON_12:
2905             case DAY_1: case DAY_2: case DAY_3: case DAY_4:
2906             case DAY_5: case DAY_6: case DAY_7:
2907             case MON_1: case MON_2: case MON_3: case MON_4:
2908             case MON_5: case MON_6: case MON_7: case MON_8:
2909             case MON_9: case MON_10: case MON_11: case MON_12:
2910 
2911                 init_tm(&tm);   /* Precaution against core dumps */
2912                 tm.tm_sec = 30;
2913                 tm.tm_min = 30;
2914                 tm.tm_hour = 6;
2915                 tm.tm_year = 2017 - 1900;
2916                 tm.tm_wday = 0;
2917                 tm.tm_mon = 0;
2918 
2919                 GCC_DIAG_IGNORE_STMT(-Wimplicit-fallthrough);
2920 
2921                 switch (item) {
2922                     default:
2923                         Perl_croak(aTHX_
2924                                     "panic: %s: %d: switch case: %d problem",
2925                                        __FILE__, __LINE__, item);
2926                         NOT_REACHED; /* NOTREACHED */
2927 
2928                     case PM_STR: tm.tm_hour = 18;
2929                     case AM_STR:
2930                         format = "%p";
2931                         break;
2932 
2933                     case ABDAY_7: tm.tm_wday++;
2934                     case ABDAY_6: tm.tm_wday++;
2935                     case ABDAY_5: tm.tm_wday++;
2936                     case ABDAY_4: tm.tm_wday++;
2937                     case ABDAY_3: tm.tm_wday++;
2938                     case ABDAY_2: tm.tm_wday++;
2939                     case ABDAY_1:
2940                         format = "%a";
2941                         break;
2942 
2943                     case DAY_7: tm.tm_wday++;
2944                     case DAY_6: tm.tm_wday++;
2945                     case DAY_5: tm.tm_wday++;
2946                     case DAY_4: tm.tm_wday++;
2947                     case DAY_3: tm.tm_wday++;
2948                     case DAY_2: tm.tm_wday++;
2949                     case DAY_1:
2950                         format = "%A";
2951                         break;
2952 
2953                     case ABMON_12: tm.tm_mon++;
2954                     case ABMON_11: tm.tm_mon++;
2955                     case ABMON_10: tm.tm_mon++;
2956                     case ABMON_9: tm.tm_mon++;
2957                     case ABMON_8: tm.tm_mon++;
2958                     case ABMON_7: tm.tm_mon++;
2959                     case ABMON_6: tm.tm_mon++;
2960                     case ABMON_5: tm.tm_mon++;
2961                     case ABMON_4: tm.tm_mon++;
2962                     case ABMON_3: tm.tm_mon++;
2963                     case ABMON_2: tm.tm_mon++;
2964                     case ABMON_1:
2965                         format = "%b";
2966                         break;
2967 
2968                     case MON_12: tm.tm_mon++;
2969                     case MON_11: tm.tm_mon++;
2970                     case MON_10: tm.tm_mon++;
2971                     case MON_9: tm.tm_mon++;
2972                     case MON_8: tm.tm_mon++;
2973                     case MON_7: tm.tm_mon++;
2974                     case MON_6: tm.tm_mon++;
2975                     case MON_5: tm.tm_mon++;
2976                     case MON_4: tm.tm_mon++;
2977                     case MON_3: tm.tm_mon++;
2978                     case MON_2: tm.tm_mon++;
2979                     case MON_1:
2980                         format = "%B";
2981                         break;
2982 
2983                     case T_FMT_AMPM:
2984                         format = "%r";
2985                         return_format = TRUE;
2986                         break;
2987 
2988                     case ERA_D_FMT:
2989                         format = "%Ex";
2990                         return_format = TRUE;
2991                         break;
2992 
2993                     case ERA_T_FMT:
2994                         format = "%EX";
2995                         return_format = TRUE;
2996                         break;
2997 
2998                     case ERA_D_T_FMT:
2999                         format = "%Ec";
3000                         return_format = TRUE;
3001                         break;
3002 
3003                     case ALT_DIGITS:
3004                         tm.tm_wday = 0;
3005                         format = "%Ow";	/* Find the alternate digit for 0 */
3006                         break;
3007                 }
3008 
3009                 GCC_DIAG_RESTORE_STMT;
3010 
3011                 /* We can't use my_strftime() because it doesn't look at
3012                  * tm_wday  */
3013                 while (0 == strftime(PL_langinfo_buf, PL_langinfo_bufsize,
3014                                      format, &tm))
3015                 {
3016                     /* A zero return means one of:
3017                      *  a)  there wasn't enough space in PL_langinfo_buf
3018                      *  b)  the format, like a plain %p, returns empty
3019                      *  c)  it was an illegal format, though some
3020                      *      implementations of strftime will just return the
3021                      *      illegal format as a plain character sequence.
3022                      *
3023                      *  To quickly test for case 'b)', try again but precede
3024                      *  the format with a plain character.  If that result is
3025                      *  still empty, the problem is either 'a)' or 'c)' */
3026 
3027                     Size_t format_size = strlen(format) + 1;
3028                     Size_t mod_size = format_size + 1;
3029                     char * mod_format;
3030                     char * temp_result;
3031 
3032                     Newx(mod_format, mod_size, char);
3033                     Newx(temp_result, PL_langinfo_bufsize, char);
3034                     *mod_format = ' ';
3035                     my_strlcpy(mod_format + 1, format, mod_size);
3036                     len = strftime(temp_result,
3037                                    PL_langinfo_bufsize,
3038                                    mod_format, &tm);
3039                     Safefree(mod_format);
3040                     Safefree(temp_result);
3041 
3042                     /* If 'len' is non-zero, it means that we had a case like
3043                      * %p which means the current locale doesn't use a.m. or
3044                      * p.m., and that is valid */
3045                     if (len == 0) {
3046 
3047                         /* Here, still didn't work.  If we get well beyond a
3048                          * reasonable size, bail out to prevent an infinite
3049                          * loop. */
3050 
3051                         if (PL_langinfo_bufsize > 100 * format_size) {
3052                             *PL_langinfo_buf = '\0';
3053                         }
3054                         else {
3055                             /* Double the buffer size to retry;  Add 1 in case
3056                              * original was 0, so we aren't stuck at 0.  */
3057                             PL_langinfo_bufsize *= 2;
3058                             PL_langinfo_bufsize++;
3059                             Renew(PL_langinfo_buf, PL_langinfo_bufsize, char);
3060                             continue;
3061                         }
3062                     }
3063 
3064                     break;
3065                 }
3066 
3067                 /* Here, we got a result.
3068                  *
3069                  * If the item is 'ALT_DIGITS', PL_langinfo_buf contains the
3070                  * alternate format for wday 0.  If the value is the same as
3071                  * the normal 0, there isn't an alternate, so clear the buffer.
3072                  * */
3073                 if (   item == ALT_DIGITS
3074                     && strEQ(PL_langinfo_buf, "0"))
3075                 {
3076                     *PL_langinfo_buf = '\0';
3077                 }
3078 
3079                 /* ALT_DIGITS is problematic.  Experiments on it showed that
3080                  * strftime() did not always work properly when going from
3081                  * alt-9 to alt-10.  Only a few locales have this item defined,
3082                  * and in all of them on Linux that khw was able to find,
3083                  * nl_langinfo() merely returned the alt-0 character, possibly
3084                  * doubled.  Most Unicode digits are in blocks of 10
3085                  * consecutive code points, so that is sufficient information
3086                  * for those scripts, as we can infer alt-1, alt-2, ....  But
3087                  * for a Japanese locale, a CJK ideographic 0 is returned, and
3088                  * the CJK digits are not in code point order, so you can't
3089                  * really infer anything.  The localedef for this locale did
3090                  * specify the succeeding digits, so that strftime() works
3091                  * properly on them, without needing to infer anything.  But
3092                  * the nl_langinfo() return did not give sufficient information
3093                  * for the caller to understand what's going on.  So until
3094                  * there is evidence that it should work differently, this
3095                  * returns the alt-0 string for ALT_DIGITS.
3096                  *
3097                  * wday was chosen because its range is all a single digit.
3098                  * Things like tm_sec have two digits as the minimum: '00' */
3099 
3100                 retval = PL_langinfo_buf;
3101 
3102                 /* If to return the format, not the value, overwrite the buffer
3103                  * with it.  But some strftime()s will keep the original format
3104                  * if illegal, so change those to "" */
3105                 if (return_format) {
3106                     if (strEQ(PL_langinfo_buf, format)) {
3107                         *PL_langinfo_buf = '\0';
3108                     }
3109                     else {
3110                         retval = save_to_buffer(format, &PL_langinfo_buf,
3111                                                 &PL_langinfo_bufsize, 0);
3112                     }
3113                 }
3114 
3115                 break;
3116 
3117 #  endif
3118 
3119         }
3120     }
3121 
3122     return retval;
3123 
3124 #endif
3125 
3126 }
3127 
3128 /*
3129  * Initialize locale awareness.
3130  */
3131 int
3132 Perl_init_i18nl10n(pTHX_ int printwarn)
3133 {
3134     /* printwarn is
3135      *
3136      *    0 if not to output warning when setup locale is bad
3137      *    1 if to output warning based on value of PERL_BADLANG
3138      *    >1 if to output regardless of PERL_BADLANG
3139      *
3140      * returns
3141      *    1 = set ok or not applicable,
3142      *    0 = fallback to a locale of lower priority
3143      *   -1 = fallback to all locales failed, not even to the C locale
3144      *
3145      * Under -DDEBUGGING, if the environment variable PERL_DEBUG_LOCALE_INIT is
3146      * set, debugging information is output.
3147      *
3148      * This looks more complicated than it is, mainly due to the #ifdefs and
3149      * error handling.
3150      *
3151      * Besides some asserts, data structure initialization, and specific
3152      * platform complications, this routine is effectively just two things.
3153      *
3154      *    a)    setlocale(LC_ALL, "");
3155      *
3156      * which sets LC_ALL to the values in the current environment.
3157      *
3158      * And for each individual category 'foo' whose value we care about:
3159      *
3160      *    b)    save_foo = setlocale(LC_foo, NULL); handle_foo(save_foo);
3161      *
3162      * (We don't tend to care about categories like LC_PAPER, for example.)
3163      *
3164      * But there are complications.  On systems without LC_ALL, it emulates
3165      * step a) by looping through all the categories, and doing
3166      *
3167      *    setlocale(LC_foo, "");
3168      *
3169      * on each.
3170      *
3171      * And it has to deal with if this is an embedded perl, whose locale
3172      * doesn't come from the environment, but has been set up by the caller.
3173      * This is pretty simply handled: the "" in the setlocale calls is not a
3174      * string constant, but a variable which is set to NULL in the embedded
3175      * case.
3176      *
3177      * But the major complication is handling failure and doing fallback.
3178      * There is an array, trial_locales, the elements of which are looped over
3179      * until the locale is successfully set.  The array is initialized with
3180      * just one element, for
3181      *      setlocale(LC_ALL, $NULL_or_empty)
3182      * If that works, as it almost always does, there's no more elements and
3183      * the loop iterates just the once.  Otherwise elements are added for each
3184      * of the environment variables that POSIX dictates should control the
3185      * program, in priority order, with a final one being "C".  The loop is
3186      * repeated until the first one succeeds.  If all fail, we limp along with
3187      * whatever state we got to.  If there is no LC_ALL, an inner loop is run
3188      * through all categories (making things look complex).
3189      *
3190      * A further complication is that Windows has an additional fallback, the
3191      * user-default ANSI code page obtained from the operating system.  This is
3192      * added as yet another loop iteration, just before the final "C"
3193      *
3194      * On Ultrix, the locale MUST come from the environment, so there is
3195      * preliminary code to set it.  I (khw) am not sure that it is necessary,
3196      * and that this couldn't be folded into the loop, but barring any real
3197      * platforms to test on, it's staying as-is
3198      */
3199 
3200     int ok = 1;
3201 
3202 #ifndef USE_LOCALE
3203 
3204     PERL_UNUSED_ARG(printwarn);
3205 
3206 #else  /* USE_LOCALE */
3207 #  ifdef __GLIBC__
3208 
3209     const char * const language = PerlEnv_getenv("LANGUAGE");
3210 
3211 #  endif
3212 
3213     /* NULL uses the existing already set up locale */
3214     const char * const setlocale_init = (PerlEnv_getenv("PERL_SKIP_LOCALE_INIT"))
3215                                         ? NULL
3216                                         : "";
3217     const char* trial_locales[5];   /* 5 = 1 each for "", LC_ALL, LANG, "", C */
3218     unsigned int trial_locales_count;
3219     const char * const lc_all     = PerlEnv_getenv("LC_ALL");
3220     const char * const lang       = PerlEnv_getenv("LANG");
3221     bool setlocale_failure = FALSE;
3222     unsigned int i;
3223 
3224     /* A later getenv() could zap this, so only use here */
3225     const char * const bad_lang_use_once = PerlEnv_getenv("PERL_BADLANG");
3226 
3227     const bool locwarn = (printwarn > 1
3228                           || (          printwarn
3229                               && (    ! bad_lang_use_once
3230                                   || (
3231                                          /* disallow with "" or "0" */
3232                                          *bad_lang_use_once
3233                                        && strNE("0", bad_lang_use_once)))));
3234 
3235     /* setlocale() return vals; not copied so must be looked at immediately */
3236     const char * sl_result[NOMINAL_LC_ALL_INDEX + 1];
3237 
3238     /* current locale for given category; should have been copied so aren't
3239      * volatile */
3240     const char * curlocales[NOMINAL_LC_ALL_INDEX + 1];
3241 
3242 #  ifdef WIN32
3243 
3244     /* In some systems you can find out the system default locale
3245      * and use that as the fallback locale. */
3246 #    define SYSTEM_DEFAULT_LOCALE
3247 #  endif
3248 #  ifdef SYSTEM_DEFAULT_LOCALE
3249 
3250     const char *system_default_locale = NULL;
3251 
3252 #  endif
3253 
3254 #  ifndef DEBUGGING
3255 #    define DEBUG_LOCALE_INIT(a,b,c)
3256 #  else
3257 
3258     DEBUG_INITIALIZATION_set(cBOOL(PerlEnv_getenv("PERL_DEBUG_LOCALE_INIT")));
3259 
3260 #    define DEBUG_LOCALE_INIT(category, locale, result)                     \
3261         STMT_START {                                                        \
3262                 if (debug_initialization) {                                 \
3263                     PerlIO_printf(Perl_debug_log,                           \
3264                                   "%s:%d: %s\n",                            \
3265                                   __FILE__, __LINE__,                       \
3266                                   setlocale_debug_string(category,          \
3267                                                           locale,           \
3268                                                           result));         \
3269                 }                                                           \
3270         } STMT_END
3271 
3272 /* Make sure the parallel arrays are properly set up */
3273 #    ifdef USE_LOCALE_NUMERIC
3274     assert(categories[LC_NUMERIC_INDEX] == LC_NUMERIC);
3275     assert(strEQ(category_names[LC_NUMERIC_INDEX], "LC_NUMERIC"));
3276 #      ifdef USE_POSIX_2008_LOCALE
3277     assert(category_masks[LC_NUMERIC_INDEX] == LC_NUMERIC_MASK);
3278 #      endif
3279 #    endif
3280 #    ifdef USE_LOCALE_CTYPE
3281     assert(categories[LC_CTYPE_INDEX] == LC_CTYPE);
3282     assert(strEQ(category_names[LC_CTYPE_INDEX], "LC_CTYPE"));
3283 #      ifdef USE_POSIX_2008_LOCALE
3284     assert(category_masks[LC_CTYPE_INDEX] == LC_CTYPE_MASK);
3285 #      endif
3286 #    endif
3287 #    ifdef USE_LOCALE_COLLATE
3288     assert(categories[LC_COLLATE_INDEX] == LC_COLLATE);
3289     assert(strEQ(category_names[LC_COLLATE_INDEX], "LC_COLLATE"));
3290 #      ifdef USE_POSIX_2008_LOCALE
3291     assert(category_masks[LC_COLLATE_INDEX] == LC_COLLATE_MASK);
3292 #      endif
3293 #    endif
3294 #    ifdef USE_LOCALE_TIME
3295     assert(categories[LC_TIME_INDEX] == LC_TIME);
3296     assert(strEQ(category_names[LC_TIME_INDEX], "LC_TIME"));
3297 #      ifdef USE_POSIX_2008_LOCALE
3298     assert(category_masks[LC_TIME_INDEX] == LC_TIME_MASK);
3299 #      endif
3300 #    endif
3301 #    ifdef USE_LOCALE_MESSAGES
3302     assert(categories[LC_MESSAGES_INDEX] == LC_MESSAGES);
3303     assert(strEQ(category_names[LC_MESSAGES_INDEX], "LC_MESSAGES"));
3304 #      ifdef USE_POSIX_2008_LOCALE
3305     assert(category_masks[LC_MESSAGES_INDEX] == LC_MESSAGES_MASK);
3306 #      endif
3307 #    endif
3308 #    ifdef USE_LOCALE_MONETARY
3309     assert(categories[LC_MONETARY_INDEX] == LC_MONETARY);
3310     assert(strEQ(category_names[LC_MONETARY_INDEX], "LC_MONETARY"));
3311 #      ifdef USE_POSIX_2008_LOCALE
3312     assert(category_masks[LC_MONETARY_INDEX] == LC_MONETARY_MASK);
3313 #      endif
3314 #    endif
3315 #    ifdef USE_LOCALE_ADDRESS
3316     assert(categories[LC_ADDRESS_INDEX] == LC_ADDRESS);
3317     assert(strEQ(category_names[LC_ADDRESS_INDEX], "LC_ADDRESS"));
3318 #      ifdef USE_POSIX_2008_LOCALE
3319     assert(category_masks[LC_ADDRESS_INDEX] == LC_ADDRESS_MASK);
3320 #      endif
3321 #    endif
3322 #    ifdef USE_LOCALE_IDENTIFICATION
3323     assert(categories[LC_IDENTIFICATION_INDEX] == LC_IDENTIFICATION);
3324     assert(strEQ(category_names[LC_IDENTIFICATION_INDEX], "LC_IDENTIFICATION"));
3325 #      ifdef USE_POSIX_2008_LOCALE
3326     assert(category_masks[LC_IDENTIFICATION_INDEX] == LC_IDENTIFICATION_MASK);
3327 #      endif
3328 #    endif
3329 #    ifdef USE_LOCALE_MEASUREMENT
3330     assert(categories[LC_MEASUREMENT_INDEX] == LC_MEASUREMENT);
3331     assert(strEQ(category_names[LC_MEASUREMENT_INDEX], "LC_MEASUREMENT"));
3332 #      ifdef USE_POSIX_2008_LOCALE
3333     assert(category_masks[LC_MEASUREMENT_INDEX] == LC_MEASUREMENT_MASK);
3334 #      endif
3335 #    endif
3336 #    ifdef USE_LOCALE_PAPER
3337     assert(categories[LC_PAPER_INDEX] == LC_PAPER);
3338     assert(strEQ(category_names[LC_PAPER_INDEX], "LC_PAPER"));
3339 #      ifdef USE_POSIX_2008_LOCALE
3340     assert(category_masks[LC_PAPER_INDEX] == LC_PAPER_MASK);
3341 #      endif
3342 #    endif
3343 #    ifdef USE_LOCALE_TELEPHONE
3344     assert(categories[LC_TELEPHONE_INDEX] == LC_TELEPHONE);
3345     assert(strEQ(category_names[LC_TELEPHONE_INDEX], "LC_TELEPHONE"));
3346 #      ifdef USE_POSIX_2008_LOCALE
3347     assert(category_masks[LC_TELEPHONE_INDEX] == LC_TELEPHONE_MASK);
3348 #      endif
3349 #    endif
3350 #    ifdef USE_LOCALE_SYNTAX
3351     assert(categories[LC_SYNTAX_INDEX] == LC_SYNTAX);
3352     assert(strEQ(category_names[LC_SYNTAX_INDEX], "LC_SYNTAX"));
3353 #      ifdef USE_POSIX_2008_LOCALE
3354     assert(category_masks[LC_SYNTAX_INDEX] == LC_SYNTAX_MASK);
3355 #      endif
3356 #    endif
3357 #    ifdef USE_LOCALE_TOD
3358     assert(categories[LC_TOD_INDEX] == LC_TOD);
3359     assert(strEQ(category_names[LC_TOD_INDEX], "LC_TOD"));
3360 #      ifdef USE_POSIX_2008_LOCALE
3361     assert(category_masks[LC_TOD_INDEX] == LC_TOD_MASK);
3362 #      endif
3363 #    endif
3364 #    ifdef LC_ALL
3365     assert(categories[LC_ALL_INDEX] == LC_ALL);
3366     assert(strEQ(category_names[LC_ALL_INDEX], "LC_ALL"));
3367     assert(NOMINAL_LC_ALL_INDEX == LC_ALL_INDEX);
3368 #      ifdef USE_POSIX_2008_LOCALE
3369     assert(category_masks[LC_ALL_INDEX] == LC_ALL_MASK);
3370 #      endif
3371 #    endif
3372 #  endif    /* DEBUGGING */
3373 
3374     /* Initialize the per-thread mbrFOO() state variables.  See POSIX.xs for
3375      * why these particular incantations are used. */
3376 #ifdef HAS_MBRLEN
3377     memzero(&PL_mbrlen_ps, sizeof(PL_mbrlen_ps));
3378 #endif
3379 #ifdef HAS_MBRTOWC
3380     memzero(&PL_mbrtowc_ps, sizeof(PL_mbrtowc_ps));
3381 #endif
3382 #ifdef HAS_WCTOMBR
3383     wcrtomb(NULL, L'\0', &PL_wcrtomb_ps);
3384 #endif
3385 
3386     /* Initialize the cache of the program's UTF-8ness for the always known
3387      * locales C and POSIX */
3388     my_strlcpy(PL_locale_utf8ness, C_and_POSIX_utf8ness,
3389                sizeof(PL_locale_utf8ness));
3390 
3391 #  ifdef USE_THREAD_SAFE_LOCALE
3392 #    ifdef WIN32
3393 
3394     _configthreadlocale(_ENABLE_PER_THREAD_LOCALE);
3395 
3396 #    endif
3397 #  endif
3398 #  ifdef USE_POSIX_2008_LOCALE
3399 
3400     PL_C_locale_obj = newlocale(LC_ALL_MASK, "C", (locale_t) 0);
3401     if (! PL_C_locale_obj) {
3402         Perl_croak_nocontext(
3403             "panic: Cannot create POSIX 2008 C locale object; errno=%d", errno);
3404     }
3405     if (DEBUG_Lv_TEST || debug_initialization) {
3406         PerlIO_printf(Perl_debug_log, "%s:%d: created C object %p\n", __FILE__, __LINE__, PL_C_locale_obj);
3407     }
3408 
3409 #  endif
3410 
3411 #  ifdef USE_LOCALE_NUMERIC
3412 
3413     PL_numeric_radix_sv = newSVpvs(".");
3414 
3415 #  endif
3416 
3417 #  if defined(USE_POSIX_2008_LOCALE) && ! defined(HAS_QUERYLOCALE)
3418 
3419     /* Initialize our records.  If we have POSIX 2008, we have LC_ALL */
3420     do_setlocale_c(LC_ALL, my_setlocale(LC_ALL, NULL));
3421 
3422 #  endif
3423 #  ifdef LOCALE_ENVIRON_REQUIRED
3424 
3425     /*
3426      * Ultrix setlocale(..., "") fails if there are no environment
3427      * variables from which to get a locale name.
3428      */
3429 
3430 #    ifndef LC_ALL
3431 #      error Ultrix without LC_ALL not implemented
3432 #    else
3433 
3434     {
3435         bool done = FALSE;
3436         if (lang) {
3437             sl_result[LC_ALL_INDEX] = do_setlocale_c(LC_ALL, setlocale_init);
3438             DEBUG_LOCALE_INIT(LC_ALL, setlocale_init, sl_result[LC_ALL_INDEX]);
3439             if (sl_result[LC_ALL_INDEX])
3440                 done = TRUE;
3441             else
3442                 setlocale_failure = TRUE;
3443         }
3444         if (! setlocale_failure) {
3445             const char * locale_param;
3446             for (i = 0; i < LC_ALL_INDEX; i++) {
3447                 locale_param = (! done && (lang || PerlEnv_getenv(category_names[i])))
3448                             ? setlocale_init
3449                             : NULL;
3450                 sl_result[i] = do_setlocale_r(categories[i], locale_param);
3451                 if (! sl_result[i]) {
3452                     setlocale_failure = TRUE;
3453                 }
3454                 DEBUG_LOCALE_INIT(categories[i], locale_param, sl_result[i]);
3455             }
3456         }
3457     }
3458 
3459 #    endif /* LC_ALL */
3460 #  endif /* LOCALE_ENVIRON_REQUIRED */
3461 
3462     /* We try each locale in the list until we get one that works, or exhaust
3463      * the list.  Normally the loop is executed just once.  But if setting the
3464      * locale fails, inside the loop we add fallback trials to the array and so
3465      * will execute the loop multiple times */
3466     trial_locales[0] = setlocale_init;
3467     trial_locales_count = 1;
3468 
3469     for (i= 0; i < trial_locales_count; i++) {
3470         const char * trial_locale = trial_locales[i];
3471 
3472         if (i > 0) {
3473 
3474             /* XXX This is to preserve old behavior for LOCALE_ENVIRON_REQUIRED
3475              * when i==0, but I (khw) don't think that behavior makes much
3476              * sense */
3477             setlocale_failure = FALSE;
3478 
3479 #  ifdef SYSTEM_DEFAULT_LOCALE
3480 #    ifdef WIN32    /* Note that assumes Win32 has LC_ALL */
3481 
3482             /* On Windows machines, an entry of "" after the 0th means to use
3483              * the system default locale, which we now proceed to get. */
3484             if (strEQ(trial_locale, "")) {
3485                 unsigned int j;
3486 
3487                 /* Note that this may change the locale, but we are going to do
3488                  * that anyway just below */
3489                 system_default_locale = do_setlocale_c(LC_ALL, "");
3490                 DEBUG_LOCALE_INIT(LC_ALL, "", system_default_locale);
3491 
3492                 /* Skip if invalid or if it's already on the list of locales to
3493                  * try */
3494                 if (! system_default_locale) {
3495                     goto next_iteration;
3496                 }
3497                 for (j = 0; j < trial_locales_count; j++) {
3498                     if (strEQ(system_default_locale, trial_locales[j])) {
3499                         goto next_iteration;
3500                     }
3501                 }
3502 
3503                 trial_locale = system_default_locale;
3504             }
3505 #    else
3506 #      error SYSTEM_DEFAULT_LOCALE only implemented for Win32
3507 #    endif
3508 #  endif /* SYSTEM_DEFAULT_LOCALE */
3509 
3510         }   /* For i > 0 */
3511 
3512 #  ifdef LC_ALL
3513 
3514         sl_result[LC_ALL_INDEX] = do_setlocale_c(LC_ALL, trial_locale);
3515         DEBUG_LOCALE_INIT(LC_ALL, trial_locale, sl_result[LC_ALL_INDEX]);
3516         if (! sl_result[LC_ALL_INDEX]) {
3517             setlocale_failure = TRUE;
3518         }
3519         else {
3520             /* Since LC_ALL succeeded, it should have changed all the other
3521              * categories it can to its value; so we massage things so that the
3522              * setlocales below just return their category's current values.
3523              * This adequately handles the case in NetBSD where LC_COLLATE may
3524              * not be defined for a locale, and setting it individually will
3525              * fail, whereas setting LC_ALL succeeds, leaving LC_COLLATE set to
3526              * the POSIX locale. */
3527             trial_locale = NULL;
3528         }
3529 
3530 #  endif /* LC_ALL */
3531 
3532         if (! setlocale_failure) {
3533             unsigned int j;
3534             for (j = 0; j < NOMINAL_LC_ALL_INDEX; j++) {
3535                 curlocales[j]
3536                         = savepv(do_setlocale_r(categories[j], trial_locale));
3537                 if (! curlocales[j]) {
3538                     setlocale_failure = TRUE;
3539                 }
3540                 DEBUG_LOCALE_INIT(categories[j], trial_locale, curlocales[j]);
3541             }
3542 
3543             if (LIKELY(! setlocale_failure)) {  /* All succeeded */
3544                 break;  /* Exit trial_locales loop */
3545             }
3546         }
3547 
3548         /* Here, something failed; will need to try a fallback. */
3549         ok = 0;
3550 
3551         if (i == 0) {
3552             unsigned int j;
3553 
3554             if (locwarn) { /* Output failure info only on the first one */
3555 
3556 #  ifdef LC_ALL
3557 
3558                 PerlIO_printf(Perl_error_log,
3559                 "perl: warning: Setting locale failed.\n");
3560 
3561 #  else /* !LC_ALL */
3562 
3563                 PerlIO_printf(Perl_error_log,
3564                 "perl: warning: Setting locale failed for the categories:\n\t");
3565 
3566                 for (j = 0; j < NOMINAL_LC_ALL_INDEX; j++) {
3567                     if (! curlocales[j]) {
3568                         PerlIO_printf(Perl_error_log, category_names[j]);
3569                     }
3570                     else {
3571                         Safefree(curlocales[j]);
3572                     }
3573                 }
3574 
3575 #  endif /* LC_ALL */
3576 
3577                 PerlIO_printf(Perl_error_log,
3578                     "perl: warning: Please check that your locale settings:\n");
3579 
3580 #  ifdef __GLIBC__
3581 
3582                 PerlIO_printf(Perl_error_log,
3583                             "\tLANGUAGE = %c%s%c,\n",
3584                             language ? '"' : '(',
3585                             language ? language : "unset",
3586                             language ? '"' : ')');
3587 #  endif
3588 
3589                 PerlIO_printf(Perl_error_log,
3590                             "\tLC_ALL = %c%s%c,\n",
3591                             lc_all ? '"' : '(',
3592                             lc_all ? lc_all : "unset",
3593                             lc_all ? '"' : ')');
3594 
3595 #  if defined(USE_ENVIRON_ARRAY)
3596 
3597                 {
3598                     char **e;
3599 
3600                     /* Look through the environment for any variables of the
3601                      * form qr/ ^ LC_ [A-Z]+ = /x, except LC_ALL which was
3602                      * already handled above.  These are assumed to be locale
3603                      * settings.  Output them and their values. */
3604                     for (e = environ; *e; e++) {
3605                         const STRLEN prefix_len = sizeof("LC_") - 1;
3606                         STRLEN uppers_len;
3607 
3608                         if (     strBEGINs(*e, "LC_")
3609                             && ! strBEGINs(*e, "LC_ALL=")
3610                             && (uppers_len = strspn(*e + prefix_len,
3611                                              "ABCDEFGHIJKLMNOPQRSTUVWXYZ"))
3612                             && ((*e)[prefix_len + uppers_len] == '='))
3613                         {
3614                             PerlIO_printf(Perl_error_log, "\t%.*s = \"%s\",\n",
3615                                 (int) (prefix_len + uppers_len), *e,
3616                                 *e + prefix_len + uppers_len + 1);
3617                         }
3618                     }
3619                 }
3620 
3621 #  else
3622 
3623                 PerlIO_printf(Perl_error_log,
3624                             "\t(possibly more locale environment variables)\n");
3625 
3626 #  endif
3627 
3628                 PerlIO_printf(Perl_error_log,
3629                             "\tLANG = %c%s%c\n",
3630                             lang ? '"' : '(',
3631                             lang ? lang : "unset",
3632                             lang ? '"' : ')');
3633 
3634                 PerlIO_printf(Perl_error_log,
3635                             "    are supported and installed on your system.\n");
3636             }
3637 
3638             /* Calculate what fallback locales to try.  We have avoided this
3639              * until we have to, because failure is quite unlikely.  This will
3640              * usually change the upper bound of the loop we are in.
3641              *
3642              * Since the system's default way of setting the locale has not
3643              * found one that works, We use Perl's defined ordering: LC_ALL,
3644              * LANG, and the C locale.  We don't try the same locale twice, so
3645              * don't add to the list if already there.  (On POSIX systems, the
3646              * LC_ALL element will likely be a repeat of the 0th element "",
3647              * but there's no harm done by doing it explicitly.
3648              *
3649              * Note that this tries the LC_ALL environment variable even on
3650              * systems which have no LC_ALL locale setting.  This may or may
3651              * not have been originally intentional, but there's no real need
3652              * to change the behavior. */
3653             if (lc_all) {
3654                 for (j = 0; j < trial_locales_count; j++) {
3655                     if (strEQ(lc_all, trial_locales[j])) {
3656                         goto done_lc_all;
3657                     }
3658                 }
3659                 trial_locales[trial_locales_count++] = lc_all;
3660             }
3661           done_lc_all:
3662 
3663             if (lang) {
3664                 for (j = 0; j < trial_locales_count; j++) {
3665                     if (strEQ(lang, trial_locales[j])) {
3666                         goto done_lang;
3667                     }
3668                 }
3669                 trial_locales[trial_locales_count++] = lang;
3670             }
3671           done_lang:
3672 
3673 #  if defined(WIN32) && defined(LC_ALL)
3674 
3675             /* For Windows, we also try the system default locale before "C".
3676              * (If there exists a Windows without LC_ALL we skip this because
3677              * it gets too complicated.  For those, the "C" is the next
3678              * fallback possibility).  The "" is the same as the 0th element of
3679              * the array, but the code at the loop above knows to treat it
3680              * differently when not the 0th */
3681             trial_locales[trial_locales_count++] = "";
3682 
3683 #  endif
3684 
3685             for (j = 0; j < trial_locales_count; j++) {
3686                 if (strEQ("C", trial_locales[j])) {
3687                     goto done_C;
3688                 }
3689             }
3690             trial_locales[trial_locales_count++] = "C";
3691 
3692           done_C: ;
3693         }   /* end of first time through the loop */
3694 
3695 #  ifdef WIN32
3696 
3697       next_iteration: ;
3698 
3699 #  endif
3700 
3701     }   /* end of looping through the trial locales */
3702 
3703     if (ok < 1) {   /* If we tried to fallback */
3704         const char* msg;
3705         if (! setlocale_failure) {  /* fallback succeeded */
3706            msg = "Falling back to";
3707         }
3708         else {  /* fallback failed */
3709             unsigned int j;
3710 
3711             /* We dropped off the end of the loop, so have to decrement i to
3712              * get back to the value the last time through */
3713             i--;
3714 
3715             ok = -1;
3716             msg = "Failed to fall back to";
3717 
3718             /* To continue, we should use whatever values we've got */
3719 
3720             for (j = 0; j < NOMINAL_LC_ALL_INDEX; j++) {
3721                 Safefree(curlocales[j]);
3722                 curlocales[j] = savepv(do_setlocale_r(categories[j], NULL));
3723                 DEBUG_LOCALE_INIT(categories[j], NULL, curlocales[j]);
3724             }
3725         }
3726 
3727         if (locwarn) {
3728             const char * description;
3729             const char * name = "";
3730             if (strEQ(trial_locales[i], "C")) {
3731                 description = "the standard locale";
3732                 name = "C";
3733             }
3734 
3735 #  ifdef SYSTEM_DEFAULT_LOCALE
3736 
3737             else if (strEQ(trial_locales[i], "")) {
3738                 description = "the system default locale";
3739                 if (system_default_locale) {
3740                     name = system_default_locale;
3741                 }
3742             }
3743 
3744 #  endif /* SYSTEM_DEFAULT_LOCALE */
3745 
3746             else {
3747                 description = "a fallback locale";
3748                 name = trial_locales[i];
3749             }
3750             if (name && strNE(name, "")) {
3751                 PerlIO_printf(Perl_error_log,
3752                     "perl: warning: %s %s (\"%s\").\n", msg, description, name);
3753             }
3754             else {
3755                 PerlIO_printf(Perl_error_log,
3756                                    "perl: warning: %s %s.\n", msg, description);
3757             }
3758         }
3759     } /* End of tried to fallback */
3760 
3761     /* Done with finding the locales; update our records */
3762 
3763 #  ifdef USE_LOCALE_CTYPE
3764 
3765     new_ctype(curlocales[LC_CTYPE_INDEX]);
3766 
3767 #  endif
3768 #  ifdef USE_LOCALE_COLLATE
3769 
3770     new_collate(curlocales[LC_COLLATE_INDEX]);
3771 
3772 #  endif
3773 #  ifdef USE_LOCALE_NUMERIC
3774 
3775     new_numeric(curlocales[LC_NUMERIC_INDEX]);
3776 
3777 #  endif
3778 
3779     for (i = 0; i < NOMINAL_LC_ALL_INDEX; i++) {
3780 
3781 #  if defined(USE_ITHREADS) && ! defined(USE_THREAD_SAFE_LOCALE)
3782 
3783         /* This caches whether each category's locale is UTF-8 or not.  This
3784          * may involve changing the locale.  It is ok to do this at
3785          * initialization time before any threads have started, but not later
3786          * unless thread-safe operations are used.
3787          * Caching means that if the program heeds our dictate not to change
3788          * locales in threaded applications, this data will remain valid, and
3789          * it may get queried without having to change locales.  If the
3790          * environment is such that all categories have the same locale, this
3791          * isn't needed, as the code will not change the locale; but this
3792          * handles the uncommon case where the environment has disparate
3793          * locales for the categories */
3794         (void) _is_cur_LC_category_utf8(categories[i]);
3795 
3796 #  endif
3797 
3798         Safefree(curlocales[i]);
3799     }
3800 
3801 #  if defined(USE_PERLIO) && defined(USE_LOCALE_CTYPE)
3802 
3803     /* Set PL_utf8locale to TRUE if using PerlIO _and_ the current LC_CTYPE
3804      * locale is UTF-8.  The call to new_ctype() just above has already
3805      * calculated the latter value and saved it in PL_in_utf8_CTYPE_locale. If
3806      * both PL_utf8locale and PL_unicode (set by -C or by $ENV{PERL_UNICODE})
3807      * are true, perl.c:S_parse_body() will turn on the PerlIO :utf8 layer on
3808      * STDIN, STDOUT, STDERR, _and_ the default open discipline.  */
3809     PL_utf8locale = PL_in_utf8_CTYPE_locale;
3810 
3811     /* Set PL_unicode to $ENV{PERL_UNICODE} if using PerlIO.
3812        This is an alternative to using the -C command line switch
3813        (the -C if present will override this). */
3814     {
3815          const char *p = PerlEnv_getenv("PERL_UNICODE");
3816          PL_unicode = p ? parse_unicode_opts(&p) : 0;
3817          if (PL_unicode & PERL_UNICODE_UTF8CACHEASSERT_FLAG)
3818              PL_utf8cache = -1;
3819     }
3820 
3821 #  endif
3822 #endif /* USE_LOCALE */
3823 #ifdef DEBUGGING
3824 
3825     /* So won't continue to output stuff */
3826     DEBUG_INITIALIZATION_set(FALSE);
3827 
3828 #endif
3829 
3830     return ok;
3831 }
3832 
3833 #ifdef USE_LOCALE_COLLATE
3834 
3835 char *
3836 Perl__mem_collxfrm(pTHX_ const char *input_string,
3837                          STRLEN len,    /* Length of 'input_string' */
3838                          STRLEN *xlen,  /* Set to length of returned string
3839                                            (not including the collation index
3840                                            prefix) */
3841                          bool utf8      /* Is the input in UTF-8? */
3842                    )
3843 {
3844 
3845     /* _mem_collxfrm() is a bit like strxfrm() but with two important
3846      * differences. First, it handles embedded NULs. Second, it allocates a bit
3847      * more memory than needed for the transformed data itself.  The real
3848      * transformed data begins at offset COLLXFRM_HDR_LEN.  *xlen is set to
3849      * the length of that, and doesn't include the collation index size.
3850      * Please see sv_collxfrm() to see how this is used. */
3851 
3852 #define COLLXFRM_HDR_LEN    sizeof(PL_collation_ix)
3853 
3854     char * s = (char *) input_string;
3855     STRLEN s_strlen = strlen(input_string);
3856     char *xbuf = NULL;
3857     STRLEN xAlloc;          /* xalloc is a reserved word in VC */
3858     STRLEN length_in_chars;
3859     bool first_time = TRUE; /* Cleared after first loop iteration */
3860 
3861     PERL_ARGS_ASSERT__MEM_COLLXFRM;
3862 
3863     /* Must be NUL-terminated */
3864     assert(*(input_string + len) == '\0');
3865 
3866     /* If this locale has defective collation, skip */
3867     if (PL_collxfrm_base == 0 && PL_collxfrm_mult == 0) {
3868         DEBUG_L(PerlIO_printf(Perl_debug_log,
3869                       "_mem_collxfrm: locale's collation is defective\n"));
3870         goto bad;
3871     }
3872 
3873     /* Replace any embedded NULs with the control that sorts before any others.
3874      * This will give as good as possible results on strings that don't
3875      * otherwise contain that character, but otherwise there may be
3876      * less-than-perfect results with that character and NUL.  This is
3877      * unavoidable unless we replace strxfrm with our own implementation. */
3878     if (UNLIKELY(s_strlen < len)) {   /* Only execute if there is an embedded
3879                                          NUL */
3880         char * e = s + len;
3881         char * sans_nuls;
3882         STRLEN sans_nuls_len;
3883         int try_non_controls;
3884         char this_replacement_char[] = "?\0";   /* Room for a two-byte string,
3885                                                    making sure 2nd byte is NUL.
3886                                                  */
3887         STRLEN this_replacement_len;
3888 
3889         /* If we don't know what non-NUL control character sorts lowest for
3890          * this locale, find it */
3891         if (PL_strxfrm_NUL_replacement == '\0') {
3892             int j;
3893             char * cur_min_x = NULL;    /* The min_char's xfrm, (except it also
3894                                            includes the collation index
3895                                            prefixed. */
3896 
3897             DEBUG_Lv(PerlIO_printf(Perl_debug_log, "Looking to replace NUL\n"));
3898 
3899             /* Unlikely, but it may be that no control will work to replace
3900              * NUL, in which case we instead look for any character.  Controls
3901              * are preferred because collation order is, in general, context
3902              * sensitive, with adjoining characters affecting the order, and
3903              * controls are less likely to have such interactions, allowing the
3904              * NUL-replacement to stand on its own.  (Another way to look at it
3905              * is to imagine what would happen if the NUL were replaced by a
3906              * combining character; it wouldn't work out all that well.) */
3907             for (try_non_controls = 0;
3908                  try_non_controls < 2;
3909                  try_non_controls++)
3910             {
3911                 /* Look through all legal code points (NUL isn't) */
3912                 for (j = 1; j < 256; j++) {
3913                     char * x;       /* j's xfrm plus collation index */
3914                     STRLEN x_len;   /* length of 'x' */
3915                     STRLEN trial_len = 1;
3916                     char cur_source[] = { '\0', '\0' };
3917 
3918                     /* Skip non-controls the first time through the loop.  The
3919                      * controls in a UTF-8 locale are the L1 ones */
3920                     if (! try_non_controls && (PL_in_utf8_COLLATE_locale)
3921                                                ? ! isCNTRL_L1(j)
3922                                                : ! isCNTRL_LC(j))
3923                     {
3924                         continue;
3925                     }
3926 
3927                     /* Create a 1-char string of the current code point */
3928                     cur_source[0] = (char) j;
3929 
3930                     /* Then transform it */
3931                     x = _mem_collxfrm(cur_source, trial_len, &x_len,
3932                                       0 /* The string is not in UTF-8 */);
3933 
3934                     /* Ignore any character that didn't successfully transform.
3935                      * */
3936                     if (! x) {
3937                         continue;
3938                     }
3939 
3940                     /* If this character's transformation is lower than
3941                      * the current lowest, this one becomes the lowest */
3942                     if (   cur_min_x == NULL
3943                         || strLT(x         + COLLXFRM_HDR_LEN,
3944                                  cur_min_x + COLLXFRM_HDR_LEN))
3945                     {
3946                         PL_strxfrm_NUL_replacement = j;
3947                         Safefree(cur_min_x);
3948                         cur_min_x = x;
3949                     }
3950                     else {
3951                         Safefree(x);
3952                     }
3953                 } /* end of loop through all 255 characters */
3954 
3955                 /* Stop looking if found */
3956                 if (cur_min_x) {
3957                     break;
3958                 }
3959 
3960                 /* Unlikely, but possible, if there aren't any controls that
3961                  * work in the locale, repeat the loop, looking for any
3962                  * character that works */
3963                 DEBUG_L(PerlIO_printf(Perl_debug_log,
3964                 "_mem_collxfrm: No control worked.  Trying non-controls\n"));
3965             } /* End of loop to try first the controls, then any char */
3966 
3967             if (! cur_min_x) {
3968                 DEBUG_L(PerlIO_printf(Perl_debug_log,
3969                     "_mem_collxfrm: Couldn't find any character to replace"
3970                     " embedded NULs in locale %s with", PL_collation_name));
3971                 goto bad;
3972             }
3973 
3974             DEBUG_L(PerlIO_printf(Perl_debug_log,
3975                     "_mem_collxfrm: Replacing embedded NULs in locale %s with "
3976                     "0x%02X\n", PL_collation_name, PL_strxfrm_NUL_replacement));
3977 
3978             Safefree(cur_min_x);
3979         } /* End of determining the character that is to replace NULs */
3980 
3981         /* If the replacement is variant under UTF-8, it must match the
3982          * UTF8-ness of the original */
3983         if ( ! UVCHR_IS_INVARIANT(PL_strxfrm_NUL_replacement) && utf8) {
3984             this_replacement_char[0] =
3985                                 UTF8_EIGHT_BIT_HI(PL_strxfrm_NUL_replacement);
3986             this_replacement_char[1] =
3987                                 UTF8_EIGHT_BIT_LO(PL_strxfrm_NUL_replacement);
3988             this_replacement_len = 2;
3989         }
3990         else {
3991             this_replacement_char[0] = PL_strxfrm_NUL_replacement;
3992             /* this_replacement_char[1] = '\0' was done at initialization */
3993             this_replacement_len = 1;
3994         }
3995 
3996         /* The worst case length for the replaced string would be if every
3997          * character in it is NUL.  Multiply that by the length of each
3998          * replacement, and allow for a trailing NUL */
3999         sans_nuls_len = (len * this_replacement_len) + 1;
4000         Newx(sans_nuls, sans_nuls_len, char);
4001         *sans_nuls = '\0';
4002 
4003         /* Replace each NUL with the lowest collating control.  Loop until have
4004          * exhausted all the NULs */
4005         while (s + s_strlen < e) {
4006             my_strlcat(sans_nuls, s, sans_nuls_len);
4007 
4008             /* Do the actual replacement */
4009             my_strlcat(sans_nuls, this_replacement_char, sans_nuls_len);
4010 
4011             /* Move past the input NUL */
4012             s += s_strlen + 1;
4013             s_strlen = strlen(s);
4014         }
4015 
4016         /* And add anything that trails the final NUL */
4017         my_strlcat(sans_nuls, s, sans_nuls_len);
4018 
4019         /* Switch so below we transform this modified string */
4020         s = sans_nuls;
4021         len = strlen(s);
4022     } /* End of replacing NULs */
4023 
4024     /* Make sure the UTF8ness of the string and locale match */
4025     if (utf8 != PL_in_utf8_COLLATE_locale) {
4026         /* XXX convert above Unicode to 10FFFF? */
4027         const char * const t = s;   /* Temporary so we can later find where the
4028                                        input was */
4029 
4030         /* Here they don't match.  Change the string's to be what the locale is
4031          * expecting */
4032 
4033         if (! utf8) { /* locale is UTF-8, but input isn't; upgrade the input */
4034             s = (char *) bytes_to_utf8((const U8 *) s, &len);
4035             utf8 = TRUE;
4036         }
4037         else {   /* locale is not UTF-8; but input is; downgrade the input */
4038 
4039             s = (char *) bytes_from_utf8((const U8 *) s, &len, &utf8);
4040 
4041             /* If the downgrade was successful we are done, but if the input
4042              * contains things that require UTF-8 to represent, have to do
4043              * damage control ... */
4044             if (UNLIKELY(utf8)) {
4045 
4046                 /* What we do is construct a non-UTF-8 string with
4047                  *  1) the characters representable by a single byte converted
4048                  *     to be so (if necessary);
4049                  *  2) and the rest converted to collate the same as the
4050                  *     highest collating representable character.  That makes
4051                  *     them collate at the end.  This is similar to how we
4052                  *     handle embedded NULs, but we use the highest collating
4053                  *     code point instead of the smallest.  Like the NUL case,
4054                  *     this isn't perfect, but is the best we can reasonably
4055                  *     do.  Every above-255 code point will sort the same as
4056                  *     the highest-sorting 0-255 code point.  If that code
4057                  *     point can combine in a sequence with some other code
4058                  *     points for weight calculations, us changing something to
4059                  *     be it can adversely affect the results.  But in most
4060                  *     cases, it should work reasonably.  And note that this is
4061                  *     really an illegal situation: using code points above 255
4062                  *     on a locale where only 0-255 are valid.  If two strings
4063                  *     sort entirely equal, then the sort order for the
4064                  *     above-255 code points will be in code point order. */
4065 
4066                 utf8 = FALSE;
4067 
4068                 /* If we haven't calculated the code point with the maximum
4069                  * collating order for this locale, do so now */
4070                 if (! PL_strxfrm_max_cp) {
4071                     int j;
4072 
4073                     /* The current transformed string that collates the
4074                      * highest (except it also includes the prefixed collation
4075                      * index. */
4076                     char * cur_max_x = NULL;
4077 
4078                     /* Look through all legal code points (NUL isn't) */
4079                     for (j = 1; j < 256; j++) {
4080                         char * x;
4081                         STRLEN x_len;
4082                         char cur_source[] = { '\0', '\0' };
4083 
4084                         /* Create a 1-char string of the current code point */
4085                         cur_source[0] = (char) j;
4086 
4087                         /* Then transform it */
4088                         x = _mem_collxfrm(cur_source, 1, &x_len, FALSE);
4089 
4090                         /* If something went wrong (which it shouldn't), just
4091                          * ignore this code point */
4092                         if (! x) {
4093                             continue;
4094                         }
4095 
4096                         /* If this character's transformation is higher than
4097                          * the current highest, this one becomes the highest */
4098                         if (   cur_max_x == NULL
4099                             || strGT(x         + COLLXFRM_HDR_LEN,
4100                                      cur_max_x + COLLXFRM_HDR_LEN))
4101                         {
4102                             PL_strxfrm_max_cp = j;
4103                             Safefree(cur_max_x);
4104                             cur_max_x = x;
4105                         }
4106                         else {
4107                             Safefree(x);
4108                         }
4109                     }
4110 
4111                     if (! cur_max_x) {
4112                         DEBUG_L(PerlIO_printf(Perl_debug_log,
4113                             "_mem_collxfrm: Couldn't find any character to"
4114                             " replace above-Latin1 chars in locale %s with",
4115                             PL_collation_name));
4116                         goto bad;
4117                     }
4118 
4119                     DEBUG_L(PerlIO_printf(Perl_debug_log,
4120                             "_mem_collxfrm: highest 1-byte collating character"
4121                             " in locale %s is 0x%02X\n",
4122                             PL_collation_name,
4123                             PL_strxfrm_max_cp));
4124 
4125                     Safefree(cur_max_x);
4126                 }
4127 
4128                 /* Here we know which legal code point collates the highest.
4129                  * We are ready to construct the non-UTF-8 string.  The length
4130                  * will be at least 1 byte smaller than the input string
4131                  * (because we changed at least one 2-byte character into a
4132                  * single byte), but that is eaten up by the trailing NUL */
4133                 Newx(s, len, char);
4134 
4135                 {
4136                     STRLEN i;
4137                     STRLEN d= 0;
4138                     char * e = (char *) t + len;
4139 
4140                     for (i = 0; i < len; i+= UTF8SKIP(t + i)) {
4141                         U8 cur_char = t[i];
4142                         if (UTF8_IS_INVARIANT(cur_char)) {
4143                             s[d++] = cur_char;
4144                         }
4145                         else if (UTF8_IS_NEXT_CHAR_DOWNGRADEABLE(t + i, e)) {
4146                             s[d++] = EIGHT_BIT_UTF8_TO_NATIVE(cur_char, t[i+1]);
4147                         }
4148                         else {  /* Replace illegal cp with highest collating
4149                                    one */
4150                             s[d++] = PL_strxfrm_max_cp;
4151                         }
4152                     }
4153                     s[d++] = '\0';
4154                     Renew(s, d, char);   /* Free up unused space */
4155                 }
4156             }
4157         }
4158 
4159         /* Here, we have constructed a modified version of the input.  It could
4160          * be that we already had a modified copy before we did this version.
4161          * If so, that copy is no longer needed */
4162         if (t != input_string) {
4163             Safefree(t);
4164         }
4165     }
4166 
4167     length_in_chars = (utf8)
4168                       ? utf8_length((U8 *) s, (U8 *) s + len)
4169                       : len;
4170 
4171     /* The first element in the output is the collation id, used by
4172      * sv_collxfrm(); then comes the space for the transformed string.  The
4173      * equation should give us a good estimate as to how much is needed */
4174     xAlloc = COLLXFRM_HDR_LEN
4175            + PL_collxfrm_base
4176            + (PL_collxfrm_mult * length_in_chars);
4177     Newx(xbuf, xAlloc, char);
4178     if (UNLIKELY(! xbuf)) {
4179         DEBUG_L(PerlIO_printf(Perl_debug_log,
4180                       "_mem_collxfrm: Couldn't malloc %zu bytes\n", xAlloc));
4181         goto bad;
4182     }
4183 
4184     /* Store the collation id */
4185     *(U32*)xbuf = PL_collation_ix;
4186 
4187     /* Then the transformation of the input.  We loop until successful, or we
4188      * give up */
4189     for (;;) {
4190 
4191         *xlen = strxfrm(xbuf + COLLXFRM_HDR_LEN, s, xAlloc - COLLXFRM_HDR_LEN);
4192 
4193         /* If the transformed string occupies less space than we told strxfrm()
4194          * was available, it means it successfully transformed the whole
4195          * string. */
4196         if (*xlen < xAlloc - COLLXFRM_HDR_LEN) {
4197 
4198             /* Some systems include a trailing NUL in the returned length.
4199              * Ignore it, using a loop in case multiple trailing NULs are
4200              * returned. */
4201             while (   (*xlen) > 0
4202                    && *(xbuf + COLLXFRM_HDR_LEN + (*xlen) - 1) == '\0')
4203             {
4204                 (*xlen)--;
4205             }
4206 
4207             /* If the first try didn't get it, it means our prediction was low.
4208              * Modify the coefficients so that we predict a larger value in any
4209              * future transformations */
4210             if (! first_time) {
4211                 STRLEN needed = *xlen + 1;   /* +1 For trailing NUL */
4212                 STRLEN computed_guess = PL_collxfrm_base
4213                                       + (PL_collxfrm_mult * length_in_chars);
4214 
4215                 /* On zero-length input, just keep current slope instead of
4216                  * dividing by 0 */
4217                 const STRLEN new_m = (length_in_chars != 0)
4218                                      ? needed / length_in_chars
4219                                      : PL_collxfrm_mult;
4220 
4221                 DEBUG_Lv(PerlIO_printf(Perl_debug_log,
4222                     "%s: %d: initial size of %zu bytes for a length "
4223                     "%zu string was insufficient, %zu needed\n",
4224                     __FILE__, __LINE__,
4225                     computed_guess, length_in_chars, needed));
4226 
4227                 /* If slope increased, use it, but discard this result for
4228                  * length 1 strings, as we can't be sure that it's a real slope
4229                  * change */
4230                 if (length_in_chars > 1 && new_m  > PL_collxfrm_mult) {
4231 
4232 #  ifdef DEBUGGING
4233 
4234                     STRLEN old_m = PL_collxfrm_mult;
4235                     STRLEN old_b = PL_collxfrm_base;
4236 
4237 #  endif
4238 
4239                     PL_collxfrm_mult = new_m;
4240                     PL_collxfrm_base = 1;   /* +1 For trailing NUL */
4241                     computed_guess = PL_collxfrm_base
4242                                     + (PL_collxfrm_mult * length_in_chars);
4243                     if (computed_guess < needed) {
4244                         PL_collxfrm_base += needed - computed_guess;
4245                     }
4246 
4247                     DEBUG_Lv(PerlIO_printf(Perl_debug_log,
4248                         "%s: %d: slope is now %zu; was %zu, base "
4249                         "is now %zu; was %zu\n",
4250                         __FILE__, __LINE__,
4251                         PL_collxfrm_mult, old_m,
4252                         PL_collxfrm_base, old_b));
4253                 }
4254                 else {  /* Slope didn't change, but 'b' did */
4255                     const STRLEN new_b = needed
4256                                         - computed_guess
4257                                         + PL_collxfrm_base;
4258                     DEBUG_Lv(PerlIO_printf(Perl_debug_log,
4259                         "%s: %d: base is now %zu; was %zu\n",
4260                         __FILE__, __LINE__,
4261                         new_b, PL_collxfrm_base));
4262                     PL_collxfrm_base = new_b;
4263                 }
4264             }
4265 
4266             break;
4267         }
4268 
4269         if (UNLIKELY(*xlen >= PERL_INT_MAX)) {
4270             DEBUG_L(PerlIO_printf(Perl_debug_log,
4271                   "_mem_collxfrm: Needed %zu bytes, max permissible is %u\n",
4272                   *xlen, PERL_INT_MAX));
4273             goto bad;
4274         }
4275 
4276         /* A well-behaved strxfrm() returns exactly how much space it needs
4277          * (usually not including the trailing NUL) when it fails due to not
4278          * enough space being provided.  Assume that this is the case unless
4279          * it's been proven otherwise */
4280         if (LIKELY(PL_strxfrm_is_behaved) && first_time) {
4281             xAlloc = *xlen + COLLXFRM_HDR_LEN + 1;
4282         }
4283         else { /* Here, either:
4284                 *  1)  The strxfrm() has previously shown bad behavior; or
4285                 *  2)  It isn't the first time through the loop, which means
4286                 *      that the strxfrm() is now showing bad behavior, because
4287                 *      we gave it what it said was needed in the previous
4288                 *      iteration, and it came back saying it needed still more.
4289                 *      (Many versions of cygwin fit this.  When the buffer size
4290                 *      isn't sufficient, they return the input size instead of
4291                 *      how much is needed.)
4292                 * Increase the buffer size by a fixed percentage and try again.
4293                 * */
4294             xAlloc += (xAlloc / 4) + 1;
4295             PL_strxfrm_is_behaved = FALSE;
4296 
4297 #  ifdef DEBUGGING
4298 
4299             if (DEBUG_Lv_TEST || debug_initialization) {
4300                 PerlIO_printf(Perl_debug_log,
4301                 "_mem_collxfrm required more space than previously calculated"
4302                 " for locale %s, trying again with new guess=%zu+%zu\n",
4303                 PL_collation_name,  COLLXFRM_HDR_LEN,
4304                 xAlloc - COLLXFRM_HDR_LEN);
4305             }
4306 
4307 #  endif
4308 
4309         }
4310 
4311         Renew(xbuf, xAlloc, char);
4312         if (UNLIKELY(! xbuf)) {
4313             DEBUG_L(PerlIO_printf(Perl_debug_log,
4314                       "_mem_collxfrm: Couldn't realloc %zu bytes\n", xAlloc));
4315             goto bad;
4316         }
4317 
4318         first_time = FALSE;
4319     }
4320 
4321 
4322 #  ifdef DEBUGGING
4323 
4324     if (DEBUG_Lv_TEST || debug_initialization) {
4325 
4326         print_collxfrm_input_and_return(s, s + len, xlen, utf8);
4327         PerlIO_printf(Perl_debug_log, "Its xfrm is:");
4328         PerlIO_printf(Perl_debug_log, "%s\n",
4329                       _byte_dump_string((U8 *) xbuf + COLLXFRM_HDR_LEN,
4330                        *xlen, 1));
4331     }
4332 
4333 #  endif
4334 
4335     /* Free up unneeded space; retain ehough for trailing NUL */
4336     Renew(xbuf, COLLXFRM_HDR_LEN + *xlen + 1, char);
4337 
4338     if (s != input_string) {
4339         Safefree(s);
4340     }
4341 
4342     return xbuf;
4343 
4344   bad:
4345 
4346 #  ifdef DEBUGGING
4347 
4348     if (DEBUG_Lv_TEST || debug_initialization) {
4349         print_collxfrm_input_and_return(s, s + len, NULL, utf8);
4350     }
4351 
4352 #  endif
4353 
4354     Safefree(xbuf);
4355     if (s != input_string) {
4356         Safefree(s);
4357     }
4358     *xlen = 0;
4359 
4360     return NULL;
4361 }
4362 
4363 #  ifdef DEBUGGING
4364 
4365 STATIC void
4366 S_print_collxfrm_input_and_return(pTHX_
4367                                   const char * const s,
4368                                   const char * const e,
4369                                   const STRLEN * const xlen,
4370                                   const bool is_utf8)
4371 {
4372 
4373     PERL_ARGS_ASSERT_PRINT_COLLXFRM_INPUT_AND_RETURN;
4374 
4375     PerlIO_printf(Perl_debug_log, "_mem_collxfrm[%" UVuf "]: returning ",
4376                                                         (UV)PL_collation_ix);
4377     if (xlen) {
4378         PerlIO_printf(Perl_debug_log, "%zu", *xlen);
4379     }
4380     else {
4381         PerlIO_printf(Perl_debug_log, "NULL");
4382     }
4383     PerlIO_printf(Perl_debug_log, " for locale '%s', string='",
4384                                                             PL_collation_name);
4385     print_bytes_for_locale(s, e, is_utf8);
4386 
4387     PerlIO_printf(Perl_debug_log, "'\n");
4388 }
4389 
4390 #  endif    /* DEBUGGING */
4391 #endif /* USE_LOCALE_COLLATE */
4392 #ifdef USE_LOCALE
4393 #  ifdef DEBUGGING
4394 
4395 STATIC void
4396 S_print_bytes_for_locale(pTHX_
4397                     const char * const s,
4398                     const char * const e,
4399                     const bool is_utf8)
4400 {
4401     const char * t = s;
4402     bool prev_was_printable = TRUE;
4403     bool first_time = TRUE;
4404 
4405     PERL_ARGS_ASSERT_PRINT_BYTES_FOR_LOCALE;
4406 
4407     while (t < e) {
4408         UV cp = (is_utf8)
4409                 ?  utf8_to_uvchr_buf((U8 *) t, e, NULL)
4410                 : * (U8 *) t;
4411         if (isPRINT(cp)) {
4412             if (! prev_was_printable) {
4413                 PerlIO_printf(Perl_debug_log, " ");
4414             }
4415             PerlIO_printf(Perl_debug_log, "%c", (U8) cp);
4416             prev_was_printable = TRUE;
4417         }
4418         else {
4419             if (! first_time) {
4420                 PerlIO_printf(Perl_debug_log, " ");
4421             }
4422             PerlIO_printf(Perl_debug_log, "%02" UVXf, cp);
4423             prev_was_printable = FALSE;
4424         }
4425         t += (is_utf8) ? UTF8SKIP(t) : 1;
4426         first_time = FALSE;
4427     }
4428 }
4429 
4430 #  endif   /* #ifdef DEBUGGING */
4431 
4432 STATIC const char *
4433 S_switch_category_locale_to_template(pTHX_ const int switch_category, const int template_category, const char * template_locale)
4434 {
4435     /* Changes the locale for LC_'switch_category" to that of
4436      * LC_'template_category', if they aren't already the same.  If not NULL,
4437      * 'template_locale' is the locale that 'template_category' is in.
4438      *
4439      * Returns a copy of the name of the original locale for 'switch_category'
4440      * so can be switched back to with the companion function
4441      * restore_switched_locale(),  (NULL if no restoral is necessary.) */
4442 
4443     char * restore_to_locale = NULL;
4444 
4445     if (switch_category == template_category) { /* No changes needed */
4446         return NULL;
4447     }
4448 
4449     /* Find the original locale of the category we may need to change, so that
4450      * it can be restored to later */
4451     restore_to_locale = stdize_locale(savepv(do_setlocale_r(switch_category,
4452                                                             NULL)));
4453     if (! restore_to_locale) {
4454         Perl_croak(aTHX_
4455              "panic: %s: %d: Could not find current %s locale, errno=%d\n",
4456                 __FILE__, __LINE__, category_name(switch_category), errno);
4457     }
4458 
4459     /* If the locale of the template category wasn't passed in, find it now */
4460     if (template_locale == NULL) {
4461         template_locale = do_setlocale_r(template_category, NULL);
4462         if (! template_locale) {
4463             Perl_croak(aTHX_
4464              "panic: %s: %d: Could not find current %s locale, errno=%d\n",
4465                    __FILE__, __LINE__, category_name(template_category), errno);
4466         }
4467     }
4468 
4469     /* It the locales are the same, there's nothing to do */
4470     if (strEQ(restore_to_locale, template_locale)) {
4471         Safefree(restore_to_locale);
4472 
4473         DEBUG_Lv(PerlIO_printf(Perl_debug_log, "%s locale unchanged as %s\n",
4474                             category_name(switch_category), template_locale));
4475 
4476         return NULL;
4477     }
4478 
4479     /* Finally, change the locale to the template one */
4480     if (! do_setlocale_r(switch_category, template_locale)) {
4481         Perl_croak(aTHX_
4482          "panic: %s: %d: Could not change %s locale to %s, errno=%d\n",
4483                             __FILE__, __LINE__, category_name(switch_category),
4484                                                        template_locale, errno);
4485     }
4486 
4487     DEBUG_Lv(PerlIO_printf(Perl_debug_log, "%s locale switched to %s\n",
4488                             category_name(switch_category), template_locale));
4489 
4490     return restore_to_locale;
4491 }
4492 
4493 STATIC void
4494 S_restore_switched_locale(pTHX_ const int category, const char * const original_locale)
4495 {
4496     /* Restores the locale for LC_'category' to 'original_locale' (which is a
4497      * copy that will be freed by this function), or do nothing if the latter
4498      * parameter is NULL */
4499 
4500     if (original_locale == NULL) {
4501         return;
4502     }
4503 
4504     if (! do_setlocale_r(category, original_locale)) {
4505         Perl_croak(aTHX_
4506              "panic: %s: %d: setlocale %s restore to %s failed, errno=%d\n",
4507                  __FILE__, __LINE__,
4508                              category_name(category), original_locale, errno);
4509     }
4510 
4511     Safefree(original_locale);
4512 }
4513 
4514 /* is_cur_LC_category_utf8 uses a small char buffer to avoid malloc/free */
4515 #define CUR_LC_BUFFER_SIZE  64
4516 
4517 bool
4518 Perl__is_cur_LC_category_utf8(pTHX_ int category)
4519 {
4520     /* Returns TRUE if the current locale for 'category' is UTF-8; FALSE
4521      * otherwise. 'category' may not be LC_ALL.  If the platform doesn't have
4522      * nl_langinfo(), nor MB_CUR_MAX, this employs a heuristic, which hence
4523      * could give the wrong result.  The result will very likely be correct for
4524      * languages that have commonly used non-ASCII characters, but for notably
4525      * English, it comes down to if the locale's name ends in something like
4526      * "UTF-8".  It errs on the side of not being a UTF-8 locale.
4527      *
4528      * If the platform is early C89, not containing mbtowc(), or we are
4529      * compiled to not pay attention to LC_CTYPE, this employs heuristics.
4530      * These work very well for non-Latin locales or those whose currency
4531      * symbol isn't a '$' nor plain ASCII text.  But without LC_CTYPE and at
4532      * least MB_CUR_MAX, English locales with an ASCII currency symbol depend
4533      * on the name containing UTF-8 or not. */
4534 
4535     /* Name of current locale corresponding to the input category */
4536     const char *save_input_locale = NULL;
4537 
4538     bool is_utf8 = FALSE;                /* The return value */
4539 
4540     /* The variables below are for the cache of previous lookups using this
4541      * function.  The cache is a C string, described at the definition for
4542      * 'C_and_POSIX_utf8ness'.
4543      *
4544      * The first part of the cache is fixed, for the C and POSIX locales.  The
4545      * varying part starts just after them. */
4546     char * utf8ness_cache = PL_locale_utf8ness + STRLENs(C_and_POSIX_utf8ness);
4547 
4548     Size_t utf8ness_cache_size; /* Size of the varying portion */
4549     Size_t input_name_len;      /* Length in bytes of save_input_locale */
4550     Size_t input_name_len_with_overhead;    /* plus extra chars used to store
4551                                                the name in the cache */
4552     char * delimited;           /* The name plus the delimiters used to store
4553                                    it in the cache */
4554     char buffer[CUR_LC_BUFFER_SIZE];        /* small buffer */
4555     char * name_pos;            /* position of 'delimited' in the cache, or 0
4556                                    if not there */
4557 
4558 
4559 #  ifdef LC_ALL
4560 
4561     assert(category != LC_ALL);
4562 
4563 #  endif
4564 
4565     /* Get the desired category's locale */
4566     save_input_locale = stdize_locale(savepv(do_setlocale_r(category, NULL)));
4567     if (! save_input_locale) {
4568         Perl_croak(aTHX_
4569              "panic: %s: %d: Could not find current %s locale, errno=%d\n",
4570                      __FILE__, __LINE__, category_name(category), errno);
4571     }
4572 
4573     DEBUG_L(PerlIO_printf(Perl_debug_log,
4574                           "Current locale for %s is %s\n",
4575                           category_name(category), save_input_locale));
4576 
4577     input_name_len = strlen(save_input_locale);
4578 
4579     /* In our cache, each name is accompanied by two delimiters and a single
4580      * utf8ness digit */
4581     input_name_len_with_overhead = input_name_len + 3;
4582 
4583     if ( input_name_len_with_overhead <= CUR_LC_BUFFER_SIZE ) {
4584         /* we can use the buffer, avoid a malloc */
4585         delimited = buffer;
4586     } else { /* need a malloc */
4587         /* Allocate and populate space for a copy of the name surrounded by the
4588          * delimiters */
4589         Newx(delimited, input_name_len_with_overhead, char);
4590     }
4591 
4592     delimited[0] = UTF8NESS_SEP[0];
4593     Copy(save_input_locale, delimited + 1, input_name_len, char);
4594     delimited[input_name_len+1] = UTF8NESS_PREFIX[0];
4595     delimited[input_name_len+2] = '\0';
4596 
4597     /* And see if that is in the cache */
4598     name_pos = instr(PL_locale_utf8ness, delimited);
4599     if (name_pos) {
4600         is_utf8 = *(name_pos + input_name_len_with_overhead - 1) - '0';
4601 
4602 #  ifdef DEBUGGING
4603 
4604         if (DEBUG_Lv_TEST || debug_initialization) {
4605             PerlIO_printf(Perl_debug_log, "UTF8ness for locale %s=%d, \n",
4606                                           save_input_locale, is_utf8);
4607         }
4608 
4609 #  endif
4610 
4611         /* And, if not already in that position, move it to the beginning of
4612          * the non-constant portion of the list, since it is the most recently
4613          * used.  (We don't have to worry about overflow, since just moving
4614          * existing names around) */
4615         if (name_pos > utf8ness_cache) {
4616             Move(utf8ness_cache,
4617                  utf8ness_cache + input_name_len_with_overhead,
4618                  name_pos - utf8ness_cache, char);
4619             Copy(delimited,
4620                  utf8ness_cache,
4621                  input_name_len_with_overhead - 1, char);
4622             utf8ness_cache[input_name_len_with_overhead - 1] = is_utf8 + '0';
4623         }
4624 
4625         /* free only when not using the buffer */
4626         if ( delimited != buffer ) Safefree(delimited);
4627         Safefree(save_input_locale);
4628         return is_utf8;
4629     }
4630 
4631     /* Here we don't have stored the utf8ness for the input locale.  We have to
4632      * calculate it */
4633 
4634 #  if        defined(USE_LOCALE_CTYPE)                                  \
4635      && (    defined(HAS_NL_LANGINFO)                                   \
4636          || (defined(HAS_MBTOWC) || defined(HAS_MBRTOWC)))
4637 
4638     {
4639         const char *original_ctype_locale
4640                         = switch_category_locale_to_template(LC_CTYPE,
4641                                                              category,
4642                                                              save_input_locale);
4643 
4644         /* Here the current LC_CTYPE is set to the locale of the category whose
4645          * information is desired.  This means that nl_langinfo() and mbtowc()
4646          * should give the correct results */
4647 
4648 #    ifdef MB_CUR_MAX  /* But we can potentially rule out UTF-8ness, avoiding
4649                           calling the functions if we have this */
4650 
4651             /* Standard UTF-8 needs at least 4 bytes to represent the maximum
4652              * Unicode code point. */
4653 
4654             DEBUG_L(PerlIO_printf(Perl_debug_log, "%s: %d: MB_CUR_MAX=%d\n",
4655                                        __FILE__, __LINE__, (int) MB_CUR_MAX));
4656             if ((unsigned) MB_CUR_MAX < STRLENs(MAX_UNICODE_UTF8)) {
4657                 is_utf8 = FALSE;
4658                 restore_switched_locale(LC_CTYPE, original_ctype_locale);
4659                 goto finish_and_return;
4660             }
4661 
4662 #    endif
4663 #    if defined(HAS_NL_LANGINFO)
4664 
4665         { /* The task is easiest if the platform has this POSIX 2001 function.
4666              Except on some platforms it can wrongly return "", so have to have
4667              a fallback.  And it can return that it's UTF-8, even if there are
4668              variances from that.  For example, Turkish locales may use the
4669              alternate dotted I rules, and sometimes it appears to be a
4670              defective locale definition.  XXX We should probably check for
4671              these in the Latin1 range and warn (but on glibc, requires
4672              iswalnum() etc. due to their not handling 80-FF correctly */
4673             const char *codeset = my_nl_langinfo(CODESET, FALSE);
4674                                           /* FALSE => already in dest locale */
4675 
4676             DEBUG_Lv(PerlIO_printf(Perl_debug_log,
4677                             "\tnllanginfo returned CODESET '%s'\n", codeset));
4678 
4679             if (codeset && strNE(codeset, "")) {
4680 
4681                               /* If the implementation of foldEQ() somehow were
4682                                * to change to not go byte-by-byte, this could
4683                                * read past end of string, as only one length is
4684                                * checked.  But currently, a premature NUL will
4685                                * compare false, and it will stop there */
4686                 is_utf8 = cBOOL(   foldEQ(codeset, STR_WITH_LEN("UTF-8"))
4687                                 || foldEQ(codeset, STR_WITH_LEN("UTF8")));
4688 
4689                 DEBUG_L(PerlIO_printf(Perl_debug_log,
4690                        "\tnllanginfo returned CODESET '%s'; ?UTF8 locale=%d\n",
4691                                                      codeset,         is_utf8));
4692                 restore_switched_locale(LC_CTYPE, original_ctype_locale);
4693                 goto finish_and_return;
4694             }
4695         }
4696 
4697 #    endif
4698 #    if defined(HAS_MBTOWC) || defined(HAS_MBRTOWC)
4699      /* We can see if this is a UTF-8-like locale if have mbtowc().  It was a
4700       * late adder to C89, so very likely to have it.  However, testing has
4701       * shown that, like nl_langinfo() above, there are locales that are not
4702       * strictly UTF-8 that this will return that they are */
4703 
4704         {
4705             wchar_t wc;
4706             int len;
4707             dSAVEDERRNO;
4708 
4709 #      if defined(HAS_MBRTOWC) && defined(USE_ITHREADS)
4710 
4711             mbstate_t ps;
4712 
4713 #      endif
4714 
4715             /* mbrtowc() and mbtowc() convert a byte string to a wide
4716              * character.  Feed a byte string to one of them and check that the
4717              * result is the expected Unicode code point */
4718 
4719 #      if defined(HAS_MBRTOWC) && defined(USE_ITHREADS)
4720             /* Prefer this function if available, as it's reentrant */
4721 
4722             memzero(&ps, sizeof(ps));;
4723             PERL_UNUSED_RESULT(mbrtowc(&wc, NULL, 0, &ps)); /* Reset any shift
4724                                                                state */
4725             SETERRNO(0, 0);
4726             len = mbrtowc(&wc, STR_WITH_LEN(REPLACEMENT_CHARACTER_UTF8), &ps);
4727             SAVE_ERRNO;
4728 
4729 #      else
4730 
4731             MBTOWC_LOCK;
4732             PERL_UNUSED_RESULT(mbtowc(&wc, NULL, 0));/* Reset any shift state */
4733             SETERRNO(0, 0);
4734             len = mbtowc(&wc, STR_WITH_LEN(REPLACEMENT_CHARACTER_UTF8));
4735             SAVE_ERRNO;
4736             MBTOWC_UNLOCK;
4737 
4738 #      endif
4739 
4740             RESTORE_ERRNO;
4741             DEBUG_Lv(PerlIO_printf(Perl_debug_log,
4742                     "\treturn from mbtowc; len=%d; code_point=%x; errno=%d\n",
4743                                    len,      (unsigned int) wc, GET_ERRNO));
4744 
4745             is_utf8 = cBOOL(   len == STRLENs(REPLACEMENT_CHARACTER_UTF8)
4746                             && wc == (wchar_t) UNICODE_REPLACEMENT);
4747         }
4748 
4749 #    endif
4750 
4751         restore_switched_locale(LC_CTYPE, original_ctype_locale);
4752         goto finish_and_return;
4753     }
4754 
4755 #  else
4756 
4757         /* Here, we must have a C89 compiler that doesn't have mbtowc().  Next
4758          * try looking at the currency symbol to see if it disambiguates
4759          * things.  Often that will be in the native script, and if the symbol
4760          * isn't in UTF-8, we know that the locale isn't.  If it is non-ASCII
4761          * UTF-8, we infer that the locale is too, as the odds of a non-UTF8
4762          * string being valid UTF-8 are quite small */
4763 
4764 #    ifdef USE_LOCALE_MONETARY
4765 
4766         /* If have LC_MONETARY, we can look at the currency symbol.  Often that
4767          * will be in the native script.  We do this one first because there is
4768          * just one string to examine, so potentially avoids work */
4769 
4770         {
4771             const char *original_monetary_locale
4772                         = switch_category_locale_to_template(LC_MONETARY,
4773                                                              category,
4774                                                              save_input_locale);
4775             bool only_ascii = FALSE;
4776             const U8 * currency_string
4777                             = (const U8 *) my_nl_langinfo(CRNCYSTR, FALSE);
4778                                       /* 2nd param not relevant for this item */
4779             const U8 * first_variant;
4780 
4781             assert(   *currency_string == '-'
4782                    || *currency_string == '+'
4783                    || *currency_string == '.');
4784 
4785             currency_string++;
4786 
4787             if (is_utf8_invariant_string_loc(currency_string, 0, &first_variant))
4788             {
4789                 DEBUG_L(PerlIO_printf(Perl_debug_log, "Couldn't get currency symbol for %s, or contains only ASCII; can't use for determining if UTF-8 locale\n", save_input_locale));
4790                 only_ascii = TRUE;
4791             }
4792             else {
4793                 is_utf8 = is_strict_utf8_string(first_variant, 0);
4794             }
4795 
4796             restore_switched_locale(LC_MONETARY, original_monetary_locale);
4797 
4798             if (! only_ascii) {
4799 
4800                 /* It isn't a UTF-8 locale if the symbol is not legal UTF-8;
4801                  * otherwise assume the locale is UTF-8 if and only if the symbol
4802                  * is non-ascii UTF-8. */
4803                 DEBUG_Lv(PerlIO_printf(Perl_debug_log, "\t?Currency symbol for %s is UTF-8=%d\n",
4804                                         save_input_locale, is_utf8));
4805                 goto finish_and_return;
4806             }
4807         }
4808 
4809 #    endif /* USE_LOCALE_MONETARY */
4810 #    if defined(HAS_STRFTIME) && defined(USE_LOCALE_TIME)
4811 
4812     /* Still haven't found a non-ASCII string to disambiguate UTF-8 or not.  Try
4813      * the names of the months and weekdays, timezone, and am/pm indicator */
4814         {
4815             const char *original_time_locale
4816                             = switch_category_locale_to_template(LC_TIME,
4817                                                                  category,
4818                                                                  save_input_locale);
4819             int hour = 10;
4820             bool is_dst = FALSE;
4821             int dom = 1;
4822             int month = 0;
4823             int i;
4824             char * formatted_time;
4825 
4826             /* Here the current LC_TIME is set to the locale of the category
4827              * whose information is desired.  Look at all the days of the week and
4828              * month names, and the timezone and am/pm indicator for UTF-8 variant
4829              * characters.  The first such a one found will tell us if the locale
4830              * is UTF-8 or not */
4831 
4832             for (i = 0; i < 7 + 12; i++) {  /* 7 days; 12 months */
4833                 formatted_time = my_strftime("%A %B %Z %p",
4834                                 0, 0, hour, dom, month, 2012 - 1900, 0, 0, is_dst);
4835                 if ( ! formatted_time
4836                     || is_utf8_invariant_string((U8 *) formatted_time, 0))
4837                 {
4838 
4839                     /* Here, we didn't find a non-ASCII.  Try the next time through
4840                      * with the complemented dst and am/pm, and try with the next
4841                      * weekday.  After we have gotten all weekdays, try the next
4842                      * month */
4843                     is_dst = ! is_dst;
4844                     hour = (hour + 12) % 24;
4845                     dom++;
4846                     if (i > 6) {
4847                         month++;
4848                     }
4849                     continue;
4850                 }
4851 
4852                 /* Here, we have a non-ASCII.  Return TRUE is it is valid UTF8;
4853                  * false otherwise.  But first, restore LC_TIME to its original
4854                  * locale if we changed it */
4855                 restore_switched_locale(LC_TIME, original_time_locale);
4856 
4857                 DEBUG_Lv(PerlIO_printf(Perl_debug_log, "\t?time-related strings for %s are UTF-8=%d\n",
4858                                     save_input_locale,
4859                                     is_utf8_string((U8 *) formatted_time, 0)));
4860                 is_utf8 = is_utf8_string((U8 *) formatted_time, 0);
4861                 goto finish_and_return;
4862             }
4863 
4864             /* Falling off the end of the loop indicates all the names were just
4865              * ASCII.  Go on to the next test.  If we changed it, restore LC_TIME
4866              * to its original locale */
4867             restore_switched_locale(LC_TIME, original_time_locale);
4868             DEBUG_Lv(PerlIO_printf(Perl_debug_log, "All time-related words for %s contain only ASCII; can't use for determining if UTF-8 locale\n", save_input_locale));
4869         }
4870 
4871 #    endif
4872 
4873 #    if 0 && defined(USE_LOCALE_MESSAGES) && defined(HAS_SYS_ERRLIST)
4874 
4875     /* This code is ifdefd out because it was found to not be necessary in testing
4876      * on our dromedary test machine, which has over 700 locales.  There, this
4877      * added no value to looking at the currency symbol and the time strings.  I
4878      * left it in so as to avoid rewriting it if real-world experience indicates
4879      * that dromedary is an outlier.  Essentially, instead of returning abpve if we
4880      * haven't found illegal utf8, we continue on and examine all the strerror()
4881      * messages on the platform for utf8ness.  If all are ASCII, we still don't
4882      * know the answer; but otherwise we have a pretty good indication of the
4883      * utf8ness.  The reason this doesn't help much is that the messages may not
4884      * have been translated into the locale.  The currency symbol and time strings
4885      * are much more likely to have been translated.  */
4886         {
4887             int e;
4888             bool non_ascii = FALSE;
4889             const char *original_messages_locale
4890                             = switch_category_locale_to_template(LC_MESSAGES,
4891                                                                  category,
4892                                                                  save_input_locale);
4893             const char * errmsg = NULL;
4894 
4895             /* Here the current LC_MESSAGES is set to the locale of the category
4896              * whose information is desired.  Look through all the messages.  We
4897              * can't use Strerror() here because it may expand to code that
4898              * segfaults in miniperl */
4899 
4900             for (e = 0; e <= sys_nerr; e++) {
4901                 errno = 0;
4902                 errmsg = sys_errlist[e];
4903                 if (errno || !errmsg) {
4904                     break;
4905                 }
4906                 errmsg = savepv(errmsg);
4907                 if (! is_utf8_invariant_string((U8 *) errmsg, 0)) {
4908                     non_ascii = TRUE;
4909                     is_utf8 = is_utf8_string((U8 *) errmsg, 0);
4910                     break;
4911                 }
4912             }
4913             Safefree(errmsg);
4914 
4915             restore_switched_locale(LC_MESSAGES, original_messages_locale);
4916 
4917             if (non_ascii) {
4918 
4919                 /* Any non-UTF-8 message means not a UTF-8 locale; if all are valid,
4920                  * any non-ascii means it is one; otherwise we assume it isn't */
4921                 DEBUG_Lv(PerlIO_printf(Perl_debug_log, "\t?error messages for %s are UTF-8=%d\n",
4922                                     save_input_locale,
4923                                     is_utf8));
4924                 goto finish_and_return;
4925             }
4926 
4927             DEBUG_L(PerlIO_printf(Perl_debug_log, "All error messages for %s contain only ASCII; can't use for determining if UTF-8 locale\n", save_input_locale));
4928         }
4929 
4930 #    endif
4931 #    ifndef EBCDIC  /* On os390, even if the name ends with "UTF-8', it isn't a
4932                    UTF-8 locale */
4933 
4934     /* As a last resort, look at the locale name to see if it matches
4935      * qr/UTF -?  * 8 /ix, or some other common locale names.  This "name", the
4936      * return of setlocale(), is actually defined to be opaque, so we can't
4937      * really rely on the absence of various substrings in the name to indicate
4938      * its UTF-8ness, but if it has UTF8 in the name, it is extremely likely to
4939      * be a UTF-8 locale.  Similarly for the other common names */
4940 
4941     {
4942         const Size_t final_pos = strlen(save_input_locale) - 1;
4943 
4944         if (final_pos >= 3) {
4945             const char *name = save_input_locale;
4946 
4947             /* Find next 'U' or 'u' and look from there */
4948             while ((name += strcspn(name, "Uu") + 1)
4949                                         <= save_input_locale + final_pos - 2)
4950             {
4951                 if (   isALPHA_FOLD_NE(*name, 't')
4952                     || isALPHA_FOLD_NE(*(name + 1), 'f'))
4953                 {
4954                     continue;
4955                 }
4956                 name += 2;
4957                 if (*(name) == '-') {
4958                     if ((name > save_input_locale + final_pos - 1)) {
4959                         break;
4960                     }
4961                     name++;
4962                 }
4963                 if (*(name) == '8') {
4964                     DEBUG_L(PerlIO_printf(Perl_debug_log,
4965                                         "Locale %s ends with UTF-8 in name\n",
4966                                         save_input_locale));
4967                     is_utf8 = TRUE;
4968                     goto finish_and_return;
4969                 }
4970             }
4971             DEBUG_L(PerlIO_printf(Perl_debug_log,
4972                                 "Locale %s doesn't end with UTF-8 in name\n",
4973                                     save_input_locale));
4974         }
4975 
4976 #      ifdef WIN32
4977 
4978         /* http://msdn.microsoft.com/en-us/library/windows/desktop/dd317756.aspx */
4979         if (memENDs(save_input_locale, final_pos, "65001")) {
4980             DEBUG_L(PerlIO_printf(Perl_debug_log,
4981                         "Locale %s ends with 65001 in name, is UTF-8 locale\n",
4982                         save_input_locale));
4983             is_utf8 = TRUE;
4984             goto finish_and_return;
4985         }
4986 
4987 #      endif
4988     }
4989 #    endif
4990 
4991     /* Other common encodings are the ISO 8859 series, which aren't UTF-8.  But
4992      * since we are about to return FALSE anyway, there is no point in doing
4993      * this extra work */
4994 
4995 #    if 0
4996     if (instr(save_input_locale, "8859")) {
4997         DEBUG_L(PerlIO_printf(Perl_debug_log,
4998                              "Locale %s has 8859 in name, not UTF-8 locale\n",
4999                              save_input_locale));
5000         is_utf8 = FALSE;
5001         goto finish_and_return;
5002     }
5003 #    endif
5004 
5005     DEBUG_L(PerlIO_printf(Perl_debug_log,
5006                           "Assuming locale %s is not a UTF-8 locale\n",
5007                                     save_input_locale));
5008     is_utf8 = FALSE;
5009 
5010 #  endif /* the code that is compiled when no modern LC_CTYPE */
5011 
5012   finish_and_return:
5013 
5014     /* Cache this result so we don't have to go through all this next time. */
5015     utf8ness_cache_size = sizeof(PL_locale_utf8ness)
5016                        - (utf8ness_cache - PL_locale_utf8ness);
5017 
5018     /* But we can't save it if it is too large for the total space available */
5019     if (LIKELY(input_name_len_with_overhead < utf8ness_cache_size)) {
5020         Size_t utf8ness_cache_len = strlen(utf8ness_cache);
5021 
5022         /* Here it can fit, but we may need to clear out the oldest cached
5023          * result(s) to do so.  Check */
5024         if (utf8ness_cache_len + input_name_len_with_overhead
5025                                                         >= utf8ness_cache_size)
5026         {
5027             /* Here we have to clear something out to make room for this.
5028              * Start looking at the rightmost place where it could fit and find
5029              * the beginning of the entry that extends past that. */
5030             char * cutoff = (char *) my_memrchr(utf8ness_cache,
5031                                                 UTF8NESS_SEP[0],
5032                                                 utf8ness_cache_size
5033                                               - input_name_len_with_overhead);
5034 
5035             assert(cutoff);
5036             assert(cutoff >= utf8ness_cache);
5037 
5038             /* This and all subsequent entries must be removed */
5039             *cutoff = '\0';
5040             utf8ness_cache_len = strlen(utf8ness_cache);
5041         }
5042 
5043         /* Make space for the new entry */
5044         Move(utf8ness_cache,
5045              utf8ness_cache + input_name_len_with_overhead,
5046              utf8ness_cache_len + 1 /* Incl. trailing NUL */, char);
5047 
5048         /* And insert it */
5049         Copy(delimited, utf8ness_cache, input_name_len_with_overhead - 1, char);
5050         utf8ness_cache[input_name_len_with_overhead - 1] = is_utf8 + '0';
5051 
5052         if ((PL_locale_utf8ness[strlen(PL_locale_utf8ness)-1] & ~1) != '0') {
5053             Perl_croak(aTHX_
5054              "panic: %s: %d: Corrupt utf8ness_cache=%s\nlen=%zu,"
5055              " inserted_name=%s, its_len=%zu\n",
5056                 __FILE__, __LINE__,
5057                 PL_locale_utf8ness, strlen(PL_locale_utf8ness),
5058                 delimited, input_name_len_with_overhead);
5059         }
5060     }
5061 
5062 #  ifdef DEBUGGING
5063 
5064     if (DEBUG_Lv_TEST) {
5065         const char * s = PL_locale_utf8ness;
5066 
5067         /* Audit the structure */
5068         while (s < PL_locale_utf8ness + strlen(PL_locale_utf8ness)) {
5069             const char *e;
5070 
5071             if (*s != UTF8NESS_SEP[0]) {
5072                 Perl_croak(aTHX_
5073                            "panic: %s: %d: Corrupt utf8ness_cache: missing"
5074                            " separator %.*s<-- HERE %s\n",
5075                            __FILE__, __LINE__,
5076                            (int) (s - PL_locale_utf8ness), PL_locale_utf8ness,
5077                            s);
5078             }
5079             s++;
5080             e = strchr(s, UTF8NESS_PREFIX[0]);
5081             if (! e) {
5082                 e = PL_locale_utf8ness + strlen(PL_locale_utf8ness);
5083                 Perl_croak(aTHX_
5084                            "panic: %s: %d: Corrupt utf8ness_cache: missing"
5085                            " separator %.*s<-- HERE %s\n",
5086                            __FILE__, __LINE__,
5087                            (int) (e - PL_locale_utf8ness), PL_locale_utf8ness,
5088                            e);
5089             }
5090             e++;
5091             if (*e != '0' && *e != '1') {
5092                 Perl_croak(aTHX_
5093                            "panic: %s: %d: Corrupt utf8ness_cache: utf8ness"
5094                            " must be [01] %.*s<-- HERE %s\n",
5095                            __FILE__, __LINE__,
5096                            (int) (e + 1 - PL_locale_utf8ness),
5097                            PL_locale_utf8ness, e + 1);
5098             }
5099             if (ninstr(PL_locale_utf8ness, s, s-1, e)) {
5100                 Perl_croak(aTHX_
5101                            "panic: %s: %d: Corrupt utf8ness_cache: entry"
5102                            " has duplicate %.*s<-- HERE %s\n",
5103                            __FILE__, __LINE__,
5104                            (int) (e - PL_locale_utf8ness), PL_locale_utf8ness,
5105                            e);
5106             }
5107             s = e + 1;
5108         }
5109     }
5110 
5111     if (DEBUG_Lv_TEST || debug_initialization) {
5112 
5113         PerlIO_printf(Perl_debug_log,
5114                 "PL_locale_utf8ness is now %s; returning %d\n",
5115                                      PL_locale_utf8ness, is_utf8);
5116     }
5117 
5118 #  endif
5119 
5120     /* free only when not using the buffer */
5121     if ( delimited != buffer ) Safefree(delimited);
5122     Safefree(save_input_locale);
5123     return is_utf8;
5124 }
5125 
5126 #endif
5127 
5128 bool
5129 Perl__is_in_locale_category(pTHX_ const bool compiling, const int category)
5130 {
5131     /* Internal function which returns if we are in the scope of a pragma that
5132      * enables the locale category 'category'.  'compiling' should indicate if
5133      * this is during the compilation phase (TRUE) or not (FALSE). */
5134 
5135     const COP * const cop = (compiling) ? &PL_compiling : PL_curcop;
5136 
5137     SV *these_categories = cop_hints_fetch_pvs(cop, "locale", 0);
5138     if (! these_categories || these_categories == &PL_sv_placeholder) {
5139         return FALSE;
5140     }
5141 
5142     /* The pseudo-category 'not_characters' is -1, so just add 1 to each to get
5143      * a valid unsigned */
5144     assert(category >= -1);
5145     return cBOOL(SvUV(these_categories) & (1U << (category + 1)));
5146 }
5147 
5148 char *
5149 Perl_my_strerror(pTHX_ const int errnum)
5150 {
5151     /* Returns a mortalized copy of the text of the error message associated
5152      * with 'errnum'.  It uses the current locale's text unless the platform
5153      * doesn't have the LC_MESSAGES category or we are not being called from
5154      * within the scope of 'use locale'.  In the former case, it uses whatever
5155      * strerror returns; in the latter case it uses the text from the C locale.
5156      *
5157      * The function just calls strerror(), but temporarily switches, if needed,
5158      * to the C locale */
5159 
5160     char *errstr;
5161 
5162 #ifndef USE_LOCALE_MESSAGES
5163 
5164     /* If platform doesn't have messages category, we don't do any switching to
5165      * the C locale; we just use whatever strerror() returns */
5166 
5167     errstr = savepv(Strerror(errnum));
5168 
5169 #else   /* Has locale messages */
5170 
5171     const bool within_locale_scope = IN_LC(LC_MESSAGES);
5172 
5173 #  ifndef USE_ITHREADS
5174 
5175     /* This function is trivial without threads. */
5176     if (within_locale_scope) {
5177         errstr = savepv(strerror(errnum));
5178     }
5179     else {
5180         const char * save_locale = savepv(do_setlocale_c(LC_MESSAGES, NULL));
5181 
5182         do_setlocale_c(LC_MESSAGES, "C");
5183         errstr = savepv(strerror(errnum));
5184         do_setlocale_c(LC_MESSAGES, save_locale);
5185         Safefree(save_locale);
5186     }
5187 
5188 #  elif   defined(USE_POSIX_2008_LOCALE)                      \
5189      &&   defined(HAS_STRERROR_L)
5190 
5191     /* This function is also trivial if we don't have to worry about thread
5192      * safety and have strerror_l(), as it handles the switch of locales so we
5193      * don't have to deal with that.  We don't have to worry about thread
5194      * safety if strerror_r() is also available.  Both it and strerror_l() are
5195      * thread-safe.  Plain strerror() isn't thread safe.  But on threaded
5196      * builds when strerror_r() is available, the apparent call to strerror()
5197      * below is actually a macro that behind-the-scenes calls strerror_r(). */
5198 
5199 #    ifdef HAS_STRERROR_R
5200 
5201     if (within_locale_scope) {
5202         errstr = savepv(strerror(errnum));
5203     }
5204     else {
5205         errstr = savepv(strerror_l(errnum, PL_C_locale_obj));
5206     }
5207 
5208 #    else
5209 
5210     /* Here we have strerror_l(), but not strerror_r() and we are on a
5211      * threaded-build.  We use strerror_l() for everything, constructing a
5212      * locale to pass to it if necessary */
5213 
5214     bool do_free = FALSE;
5215     locale_t locale_to_use;
5216 
5217     if (within_locale_scope) {
5218         locale_to_use = uselocale((locale_t) 0);
5219         if (locale_to_use == LC_GLOBAL_LOCALE) {
5220             locale_to_use = duplocale(LC_GLOBAL_LOCALE);
5221             do_free = TRUE;
5222         }
5223     }
5224     else {  /* Use C locale if not within 'use locale' scope */
5225         locale_to_use = PL_C_locale_obj;
5226     }
5227 
5228     errstr = savepv(strerror_l(errnum, locale_to_use));
5229 
5230     if (do_free) {
5231         freelocale(locale_to_use);
5232     }
5233 
5234 #    endif
5235 #  else /* Doesn't have strerror_l() */
5236 
5237     const char * save_locale = NULL;
5238     bool locale_is_C = FALSE;
5239 
5240     /* We have a critical section to prevent another thread from executing this
5241      * same code at the same time.  (On thread-safe perls, the LOCK is a
5242      * no-op.)  Since this is the only place in core that changes LC_MESSAGES
5243      * (unless the user has called setlocale(), this works to prevent races. */
5244     SETLOCALE_LOCK;
5245 
5246     DEBUG_Lv(PerlIO_printf(Perl_debug_log,
5247                             "my_strerror called with errnum %d\n", errnum));
5248     if (! within_locale_scope) {
5249         save_locale = do_setlocale_c(LC_MESSAGES, NULL);
5250         if (! save_locale) {
5251             SETLOCALE_UNLOCK;
5252             Perl_croak(aTHX_
5253                  "panic: %s: %d: Could not find current LC_MESSAGES locale,"
5254                  " errno=%d\n", __FILE__, __LINE__, errno);
5255         }
5256         else {
5257             locale_is_C = isNAME_C_OR_POSIX(save_locale);
5258 
5259             /* Switch to the C locale if not already in it */
5260             if (! locale_is_C) {
5261 
5262                 /* The setlocale() just below likely will zap 'save_locale', so
5263                  * create a copy.  */
5264                 save_locale = savepv(save_locale);
5265                 if (! do_setlocale_c(LC_MESSAGES, "C")) {
5266 
5267                     /* If, for some reason, the locale change failed, we
5268                      * soldier on as best as possible under the circumstances,
5269                      * using the current locale, and clear save_locale, so we
5270                      * don't try to change back.  On z/0S, all setlocale()
5271                      * calls fail after you've created a thread.  This is their
5272                      * way of making sure the entire process is always a single
5273                      * locale.  This means that 'use locale' is always in place
5274                      * for messages under these circumstances. */
5275                     Safefree(save_locale);
5276                     save_locale = NULL;
5277                 }
5278             }
5279         }
5280     }   /* end of ! within_locale_scope */
5281     else {
5282         DEBUG_Lv(PerlIO_printf(Perl_debug_log, "%s: %d: WITHIN locale scope\n",
5283                                                __FILE__, __LINE__));
5284     }
5285 
5286     DEBUG_Lv(PerlIO_printf(Perl_debug_log,
5287              "Any locale change has been done; about to call Strerror\n"));
5288     errstr = savepv(Strerror(errnum));
5289 
5290     if (! within_locale_scope) {
5291         if (save_locale && ! locale_is_C) {
5292             if (! do_setlocale_c(LC_MESSAGES, save_locale)) {
5293                 SETLOCALE_UNLOCK;
5294                 Perl_croak(aTHX_
5295                      "panic: %s: %d: setlocale restore to '%s' failed, errno=%d\n",
5296                              __FILE__, __LINE__, save_locale, errno);
5297             }
5298             Safefree(save_locale);
5299         }
5300     }
5301 
5302     SETLOCALE_UNLOCK;
5303 
5304 #  endif /* End of doesn't have strerror_l */
5305 #  ifdef DEBUGGING
5306 
5307     if (DEBUG_Lv_TEST) {
5308         PerlIO_printf(Perl_debug_log, "Strerror returned; saving a copy: '");
5309         print_bytes_for_locale(errstr, errstr + strlen(errstr), 0);
5310         PerlIO_printf(Perl_debug_log, "'\n");
5311     }
5312 
5313 #  endif
5314 #endif   /* End of does have locale messages */
5315 
5316     SAVEFREEPV(errstr);
5317     return errstr;
5318 }
5319 
5320 /*
5321 
5322 =for apidoc switch_to_global_locale
5323 
5324 On systems without locale support, or on typical single-threaded builds, or on
5325 platforms that do not support per-thread locale operations, this function does
5326 nothing.  On such systems that do have locale support, only a locale global to
5327 the whole program is available.
5328 
5329 On multi-threaded builds on systems that do have per-thread locale operations,
5330 this function converts the thread it is running in to use the global locale.
5331 This is for code that has not yet or cannot be updated to handle multi-threaded
5332 locale operation.  As long as only a single thread is so-converted, everything
5333 works fine, as all the other threads continue to ignore the global one, so only
5334 this thread looks at it.
5335 
5336 However, on Windows systems this isn't quite true prior to Visual Studio 15,
5337 at which point Microsoft fixed a bug.  A race can occur if you use the
5338 following operations on earlier Windows platforms:
5339 
5340 =over
5341 
5342 =item L<POSIX::localeconv|POSIX/localeconv>
5343 
5344 =item L<I18N::Langinfo>, items C<CRNCYSTR> and C<THOUSEP>
5345 
5346 =item L<perlapi/Perl_langinfo>, items C<CRNCYSTR> and C<THOUSEP>
5347 
5348 =back
5349 
5350 The first item is not fixable (except by upgrading to a later Visual Studio
5351 release), but it would be possible to work around the latter two items by using
5352 the Windows API functions C<GetNumberFormat> and C<GetCurrencyFormat>; patches
5353 welcome.
5354 
5355 Without this function call, threads that use the L<C<setlocale(3)>> system
5356 function will not work properly, as all the locale-sensitive functions will
5357 look at the per-thread locale, and C<setlocale> will have no effect on this
5358 thread.
5359 
5360 Perl code should convert to either call
5361 L<C<Perl_setlocale>|perlapi/Perl_setlocale> (which is a drop-in for the system
5362 C<setlocale>) or use the methods given in L<perlcall> to call
5363 L<C<POSIX::setlocale>|POSIX/setlocale>.  Either one will transparently properly
5364 handle all cases of single- vs multi-thread, POSIX 2008-supported or not.
5365 
5366 Non-Perl libraries, such as C<gtk>, that call the system C<setlocale> can
5367 continue to work if this function is called before transferring control to the
5368 library.
5369 
5370 Upon return from the code that needs to use the global locale,
5371 L<C<sync_locale()>|perlapi/sync_locale> should be called to restore the safe
5372 multi-thread operation.
5373 
5374 =cut
5375 */
5376 
5377 void
5378 Perl_switch_to_global_locale()
5379 {
5380 
5381 #ifdef USE_THREAD_SAFE_LOCALE
5382 #  ifdef WIN32
5383 
5384     _configthreadlocale(_DISABLE_PER_THREAD_LOCALE);
5385 
5386 #  else
5387 #    ifdef HAS_QUERYLOCALE
5388 
5389     setlocale(LC_ALL, querylocale(LC_ALL_MASK, uselocale((locale_t) 0)));
5390 
5391 #    else
5392 
5393     {
5394         unsigned int i;
5395 
5396         for (i = 0; i < LC_ALL_INDEX; i++) {
5397             setlocale(categories[i], do_setlocale_r(categories[i], NULL));
5398         }
5399     }
5400 
5401 #    endif
5402 
5403     uselocale(LC_GLOBAL_LOCALE);
5404 
5405 #  endif
5406 #endif
5407 
5408 }
5409 
5410 /*
5411 
5412 =for apidoc sync_locale
5413 
5414 L<C<Perl_setlocale>|perlapi/Perl_setlocale> can be used at any time to query or
5415 change the locale (though changing the locale is antisocial and dangerous on
5416 multi-threaded systems that don't have multi-thread safe locale operations.
5417 (See L<perllocale/Multi-threaded operation>).  Using the system
5418 L<C<setlocale(3)>> should be avoided.  Nevertheless, certain non-Perl libraries
5419 called from XS, such as C<Gtk> do so, and this can't be changed.  When the
5420 locale is changed by XS code that didn't use
5421 L<C<Perl_setlocale>|perlapi/Perl_setlocale>, Perl needs to be told that the
5422 locale has changed.  Use this function to do so, before returning to Perl.
5423 
5424 The return value is a boolean: TRUE if the global locale at the time of call
5425 was in effect; and FALSE if a per-thread locale was in effect.  This can be
5426 used by the caller that needs to restore things as-they-were to decide whether
5427 or not to call
5428 L<C<Perl_switch_to_global_locale>|perlapi/switch_to_global_locale>.
5429 
5430 =cut
5431 */
5432 
5433 bool
5434 Perl_sync_locale()
5435 {
5436 
5437 #ifndef USE_LOCALE
5438 
5439     return TRUE;
5440 
5441 #else
5442 
5443     const char * newlocale;
5444     dTHX;
5445 
5446 #  ifdef USE_POSIX_2008_LOCALE
5447 
5448     bool was_in_global_locale = FALSE;
5449     locale_t cur_obj = uselocale((locale_t) 0);
5450 
5451     /* On Windows, unless the foreign code has turned off the thread-safe
5452      * locale setting, any plain setlocale() will have affected what we see, so
5453      * no need to worry.  Otherwise, If the foreign code has done a plain
5454      * setlocale(), it will only affect the global locale on POSIX systems, but
5455      * will affect the */
5456     if (cur_obj == LC_GLOBAL_LOCALE) {
5457 
5458 #    ifdef HAS_QUERY_LOCALE
5459 
5460         do_setlocale_c(LC_ALL, setlocale(LC_ALL, NULL));
5461 
5462 #    else
5463 
5464         unsigned int i;
5465 
5466         /* We can't trust that we can read the LC_ALL format on the
5467          * platform, so do them individually */
5468         for (i = 0; i < LC_ALL_INDEX; i++) {
5469             do_setlocale_r(categories[i], setlocale(categories[i], NULL));
5470         }
5471 
5472 #    endif
5473 
5474         was_in_global_locale = TRUE;
5475     }
5476 
5477 #  else
5478 
5479     bool was_in_global_locale = TRUE;
5480 
5481 #  endif
5482 #  ifdef USE_LOCALE_CTYPE
5483 
5484     newlocale = savepv(do_setlocale_c(LC_CTYPE, NULL));
5485     DEBUG_Lv(PerlIO_printf(Perl_debug_log,
5486         "%s:%d: %s\n", __FILE__, __LINE__,
5487         setlocale_debug_string(LC_CTYPE, NULL, newlocale)));
5488     new_ctype(newlocale);
5489     Safefree(newlocale);
5490 
5491 #  endif /* USE_LOCALE_CTYPE */
5492 #  ifdef USE_LOCALE_COLLATE
5493 
5494     newlocale = savepv(do_setlocale_c(LC_COLLATE, NULL));
5495     DEBUG_Lv(PerlIO_printf(Perl_debug_log,
5496         "%s:%d: %s\n", __FILE__, __LINE__,
5497         setlocale_debug_string(LC_COLLATE, NULL, newlocale)));
5498     new_collate(newlocale);
5499     Safefree(newlocale);
5500 
5501 #  endif
5502 #  ifdef USE_LOCALE_NUMERIC
5503 
5504     newlocale = savepv(do_setlocale_c(LC_NUMERIC, NULL));
5505     DEBUG_Lv(PerlIO_printf(Perl_debug_log,
5506         "%s:%d: %s\n", __FILE__, __LINE__,
5507         setlocale_debug_string(LC_NUMERIC, NULL, newlocale)));
5508     new_numeric(newlocale);
5509     Safefree(newlocale);
5510 
5511 #  endif /* USE_LOCALE_NUMERIC */
5512 
5513     return was_in_global_locale;
5514 
5515 #endif
5516 
5517 }
5518 
5519 #if defined(DEBUGGING) && defined(USE_LOCALE)
5520 
5521 STATIC char *
5522 S_setlocale_debug_string(const int category,        /* category number,
5523                                                            like LC_ALL */
5524                             const char* const locale,   /* locale name */
5525 
5526                             /* return value from setlocale() when attempting to
5527                              * set 'category' to 'locale' */
5528                             const char* const retval)
5529 {
5530     /* Returns a pointer to a NUL-terminated string in static storage with
5531      * added text about the info passed in.  This is not thread safe and will
5532      * be overwritten by the next call, so this should be used just to
5533      * formulate a string to immediately print or savepv() on. */
5534 
5535     static char ret[256];
5536 
5537     my_strlcpy(ret, "setlocale(", sizeof(ret));
5538     my_strlcat(ret, category_name(category), sizeof(ret));
5539     my_strlcat(ret, ", ", sizeof(ret));
5540 
5541     if (locale) {
5542         my_strlcat(ret, "\"", sizeof(ret));
5543         my_strlcat(ret, locale, sizeof(ret));
5544         my_strlcat(ret, "\"", sizeof(ret));
5545     }
5546     else {
5547         my_strlcat(ret, "NULL", sizeof(ret));
5548     }
5549 
5550     my_strlcat(ret, ") returned ", sizeof(ret));
5551 
5552     if (retval) {
5553         my_strlcat(ret, "\"", sizeof(ret));
5554         my_strlcat(ret, retval, sizeof(ret));
5555         my_strlcat(ret, "\"", sizeof(ret));
5556     }
5557     else {
5558         my_strlcat(ret, "NULL", sizeof(ret));
5559     }
5560 
5561     assert(strlen(ret) < sizeof(ret));
5562 
5563     return ret;
5564 }
5565 
5566 #endif
5567 
5568 void
5569 Perl_thread_locale_init()
5570 {
5571     /* Called from a thread on startup*/
5572 
5573 #ifdef USE_THREAD_SAFE_LOCALE
5574 
5575     dTHX_DEBUGGING;
5576 
5577     /* C starts the new thread in the global C locale.  If we are thread-safe,
5578      * we want to not be in the global locale */
5579 
5580      DEBUG_L(PerlIO_printf(Perl_debug_log,
5581             "%s:%d: new thread, initial locale is %s; calling setlocale\n",
5582             __FILE__, __LINE__, setlocale(LC_ALL, NULL)));
5583 
5584 #  ifdef WIN32
5585 
5586     _configthreadlocale(_ENABLE_PER_THREAD_LOCALE);
5587 
5588 #  else
5589 
5590     Perl_setlocale(LC_ALL, "C");
5591 
5592 #  endif
5593 #endif
5594 
5595 }
5596 
5597 void
5598 Perl_thread_locale_term()
5599 {
5600     /* Called from a thread as it gets ready to terminate */
5601 
5602 #ifdef USE_THREAD_SAFE_LOCALE
5603 
5604     /* C starts the new thread in the global C locale.  If we are thread-safe,
5605      * we want to not be in the global locale */
5606 
5607 #  ifndef WIN32
5608 
5609     {   /* Free up */
5610         locale_t cur_obj = uselocale(LC_GLOBAL_LOCALE);
5611         if (cur_obj != LC_GLOBAL_LOCALE && cur_obj != PL_C_locale_obj) {
5612             freelocale(cur_obj);
5613         }
5614     }
5615 
5616 #  endif
5617 #endif
5618 
5619 }
5620 
5621 /*
5622  * ex: set ts=8 sts=4 sw=4 et:
5623  */
5624