libc-top-half/musl/src/locale/newlocale.c

   1 #include <stdlib.h>
   2 #include <string.h>
   3 #if defined(__wasilibc_unmodified_upstream) || defined(_REENTRANT)
   4 #include <pthread.h>
   5 #endif
   6 #include "locale_impl.h"
   7 #include "lock.h"
   8
   9 #define malloc __libc_malloc
  10 #define calloc undef
  11 #define realloc undef
  12 #define free undef
  13
  14 static int default_locale_init_done;
  15 static struct __locale_struct default_locale, default_ctype_locale;
  16
  17 int __loc_is_allocated(locale_t loc)
  18 {
  19         return loc && loc != C_LOCALE && loc != UTF8_LOCALE
  20                 && loc != &default_locale && loc != &default_ctype_locale;
  21 }
  22
  23 static locale_t do_newlocale(int mask, const char *name, locale_t loc)
  24 {
  25         struct __locale_struct tmp;
  26
  27         for (int i=0; i<LC_ALL; i++) {
  28                 tmp.cat[i] = (!(mask & (1<<i)) && loc) ? loc->cat[i] :
  29                         __get_locale(i, (mask & (1<<i)) ? name : "");
  30                 if (tmp.cat[i] == LOC_MAP_FAILED)
  31                         return 0;
  32         }
  33
  34         /* For locales with allocated storage, modify in-place. */
  35         if (__loc_is_allocated(loc)) {
  36                 *loc = tmp;
  37                 return loc;
  38         }
  39
  40         /* Otherwise, first see if we can use one of the builtin locales.
  41          * This makes the common usage case for newlocale, getting a C locale
  42          * with predictable behavior, very fast, and more importantly, fail-safe. */
  43         if (!memcmp(&tmp, C_LOCALE, sizeof tmp)) return C_LOCALE;
  44         if (!memcmp(&tmp, UTF8_LOCALE, sizeof tmp)) return UTF8_LOCALE;
  45
  46         /* And provide builtins for the initial default locale, and a
  47          * variant of the C locale honoring the default locale's encoding. */
  48         if (!default_locale_init_done) {
  49                 for (int i=0; i<LC_ALL; i++)
  50                         default_locale.cat[i] = __get_locale(i, "");
  51                 default_ctype_locale.cat[LC_CTYPE] = default_locale.cat[LC_CTYPE];
  52                 default_locale_init_done = 1;
  53         }
  54         if (!memcmp(&tmp, &default_locale, sizeof tmp)) return &default_locale;
  55         if (!memcmp(&tmp, &default_ctype_locale, sizeof tmp))
  56                 return &default_ctype_locale;
  57
  58         /* If no builtin locale matched, attempt to allocate and copy. */
  59         if ((loc = malloc(sizeof *loc))) *loc = tmp;
  60
  61         return loc;
  62 }
  63
  64 locale_t __newlocale(int mask, const char *name, locale_t loc)
  65 {
  66         LOCK(__locale_lock);
  67         loc = do_newlocale(mask, name, loc);
  68         UNLOCK(__locale_lock);
  69         return loc;
  70 }
  71
  72 weak_alias(__newlocale, newlocale);