src/locale/setlocale.c

   1 #include <locale.h>
   2 #include <stdlib.h>
   3 #include <string.h>
   4 #include "locale_impl.h"
   5 #include "libc.h"
   6 #include "atomic.h"
   7
   8 static char buf[LC_ALL*(LOCALE_NAME_MAX+1)];
   9
  10 static char *setlocale_one_unlocked(int cat, const char *name)
  11 {
  12         const struct __locale_map *lm;
  13
  14         if (name) libc.global_locale.cat[cat] = lm = __get_locale(cat, name);
  15         else lm = libc.global_locale.cat[cat];
  16
  17         return lm ? (char *)lm->name : "C";
  18 }
  19
  20 char *__strchrnul(const char *, int);
  21
  22 char *setlocale(int cat, const char *name)
  23 {
  24         static volatile int lock[2];
  25
  26         if ((unsigned)cat > LC_ALL) return 0;
  27
  28         LOCK(lock);
  29
  30         /* For LC_ALL, setlocale is required to return a string which
  31          * encodes the current setting for all categories. The format of
  32          * this string is unspecified, and only the following code, which
  33          * performs both the serialization and deserialization, depends
  34          * on the format, so it can easily be changed if needed. */
  35         if (cat == LC_ALL) {
  36                 int i;
  37                 if (name) {
  38                         char part[LOCALE_NAME_MAX+1] = "C.UTF-8";
  39                         const char *p = name;
  40                         for (i=0; i<LC_ALL; i++) {
  41                                 const char *z = __strchrnul(p, ';');
  42                                 if (z-p <= LOCALE_NAME_MAX) {
  43                                         memcpy(part, p, z-p);
  44                                         part[z-p] = 0;
  45                                         if (*z) p = z+1;
  46                                 }
  47                                 setlocale_one_unlocked(i, part);
  48                         }
  49                 }
  50                 char *s = buf;
  51                 for (i=0; i<LC_ALL; i++) {
  52                         const struct __locale_map *lm =
  53                                 libc.global_locale.cat[i];
  54                         const char *part = lm ? lm->name : "C";
  55                         size_t l = strlen(part);
  56                         memcpy(s, part, l);
  57                         s[l] = ';';
  58                         s += l+1;
  59                 }
  60                 *--s = 0;
  61                 UNLOCK(lock);
  62                 return buf;
  63         }
  64
  65         char *ret = setlocale_one_unlocked(cat, name);
  66
  67         UNLOCK(lock);
  68
  69         return ret;
  70 }