/* nl_langinfo() replacement: query locale dependent information.

   Copyright (C) 2007-2026 Free Software Foundation, Inc.

   This file is free software: you can redistribute it and/or modify

   it under the terms of the GNU Lesser General Public License as

   published by the Free Software Foundation; either version 2.1 of the

   License, or (at your option) any later version.

   This file is distributed in the hope that it will be useful,

   but WITHOUT ANY WARRANTY; without even the implied warranty of

   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

   GNU Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public License

   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */

#include <config.h>

/* Specification.  */

#include <langinfo.h>

#include <locale.h>

#include <stdlib.h>

#include <string.h>

#if defined _WIN32 && ! defined __CYGWIN__

# define WIN32_LEAN_AND_MEAN  /* avoid including junk */

# include <windows.h>

# include <stdio.h>

#endif

#if REPLACE_NL_LANGINFO && !NL_LANGINFO_MTSAFE

# if AVOID_ANY_THREADS

/* The option '--disable-threads' explicitly requests no locking.  */

# elif defined _WIN32 && !defined __CYGWIN__

#  define WIN32_LEAN_AND_MEAN  /* avoid including junk */

#  include <windows.h>

# elif HAVE_PTHREAD_API

#  include <pthread.h>

#  if HAVE_THREADS_H && HAVE_WEAK_SYMBOLS

#   include <threads.h>

#   pragma weak thrd_exit

#   define c11_threads_in_use() (thrd_exit != NULL)

#  else

#   define c11_threads_in_use() 0

#  endif

# elif HAVE_THREADS_H

#  include <threads.h>

# endif

#endif

/* nl_langinfo() must be multithread-safe.  To achieve this without using

   thread-local storage:

     1. We use a specific static buffer for each possible argument.

        So that different threads can call nl_langinfo with different arguments,

        without interfering.

     2. We use a simple strcpy or memcpy to fill this static buffer.  Filling it

        through, for example, strcpy + strcat would not be guaranteed to leave

        the buffer's contents intact if another thread is currently accessing

        it.  If necessary, the contents is first assembled in a stack-allocated

        buffer.  */

#if !REPLACE_NL_LANGINFO || GNULIB_defined_CODESET

/* Return the codeset of the current locale, if this is easily deducible.

   Otherwise, return "".  */

static char *

ctype_codeset (void)

{

  /* This function is only used on platforms which don't have uselocale().

     Therefore we don't need to look at the per-thread locale first, here.  */

  static char result[2 + 10 + 1];

  char locale[SETLOCALE_NULL_MAX];

  if (setlocale_null_r (LC_CTYPE, locale, sizeof (locale)))

    locale[0] = '\0';

  char buf[2 + 10 + 1];

  char *codeset = buf;

  codeset[0] = '\0';

  if (locale[0])

    {

      /* If the locale name contains an encoding after the dot, return it.  */

      char *dot = strchr (locale, '.');

      if (dot)

        {

          /* Look for the possible @... trailer and remove it, if any.  */

          char *codeset_start = dot + 1;

          char const *modifier = strchr (codeset_start, '@');

          if (! modifier)

            codeset = codeset_start;

          else

            {

              size_t codesetlen = modifier - codeset_start;

              if (codesetlen < sizeof buf)

                {

                  codeset = memcpy (buf, codeset_start, codesetlen);

                  codeset[codesetlen] = '\0';

                }

            }

        }

    }

# if defined _WIN32 && ! defined __CYGWIN__

  /* If setlocale is successful, it returns the number of the

     codepage, as a string.  Otherwise, fall back on Windows API

     GetACP, which returns the locale's codepage as a number (although

     this doesn't change according to what the 'setlocale' call specified).

     Either way, prepend "CP" to make it a valid codeset name.  */

  size_t codesetlen = strlen (codeset);

  if (0 < codesetlen && codesetlen < sizeof buf - 2)

    memmove (buf + 2, codeset, codesetlen + 1);

  else

    sprintf (buf + 2, "%u", GetACP ());

  /* For a locale name such as "French_France.65001", in Windows 10,

     setlocale now returns "French_France.utf8" instead.  */

  if (streq (buf + 2, "65001") || streq (buf + 2, "utf8"))

    return (char *) "UTF-8";

  else

    {

      memcpy (buf, "CP", 2);

      strcpy (result, buf);

      return result;

    }

# else

  strcpy (result, codeset);

  return result;

#endif

}

#endif

#if REPLACE_NL_LANGINFO

/* Override nl_langinfo with support for added nl_item values.  */

# undef nl_langinfo

/* Without locking, on Solaris 11.3, test-nl_langinfo-mt fails, with message

   "thread5 disturbed by threadN!", even when threadN invokes only

      nl_langinfo (CODESET);

      nl_langinfo (CRNCYSTR);

   Similarly on Solaris 10 and macOS 26.  */

# if !NL_LANGINFO_MTSAFE /* macOS, Solaris */

#  ifdef __sun /* Solaris */

#   define ITEMS (MAXSTRMSG + 1)

#  else /* macOS */

#   define ITEMS (CRNCYSTR + 20)

#  endif

#  define MAX_RESULT_LEN 80

static char *

nl_langinfo_unlocked (nl_item item)

{

  static char result[ITEMS][MAX_RESULT_LEN];

  /* The result of nl_langinfo is in storage that can be overwritten by

     other calls to nl_langinfo.  */

  char *tmp = nl_langinfo (item);

  if (item >= 0 && item < ITEMS && tmp != NULL)

    {

      size_t tmp_len = strlen (tmp);

      if (tmp_len < MAX_RESULT_LEN)

        strcpy (result[item], tmp);

      else

        {

          /* Produce a truncated result.  Oh well...  */

          result[item][MAX_RESULT_LEN - 1] = '\0';

          memcpy (result[item], tmp, MAX_RESULT_LEN - 1);

        }

      return result[item];

    }

  else

    return tmp;

}

/* Use a lock, so that no two threads can invoke nl_langinfo_unlocked

   at the same time.  */

/* Prohibit renaming this symbol.  */

#  undef gl_get_nl_langinfo_lock

#  if AVOID_ANY_THREADS

/* The option '--disable-threads' explicitly requests no locking.  */

#   define nl_langinfo_with_lock nl_langinfo_unlocked

#  elif defined _WIN32 && !defined __CYGWIN__

extern __declspec(dllimport) CRITICAL_SECTION *gl_get_nl_langinfo_lock (void);

static char *

nl_langinfo_with_lock (nl_item item)

{

  CRITICAL_SECTION *lock = gl_get_nl_langinfo_lock ();

  EnterCriticalSection (lock);

  char *ret = nl_langinfo_unlocked (item);

  LeaveCriticalSection (lock);

  return ret;

}

#  elif HAVE_PTHREAD_API

extern

#   if defined _WIN32 || defined __CYGWIN__

  __declspec(dllimport)

#   endif

  pthread_mutex_t *gl_get_nl_langinfo_lock (void);

#   if HAVE_WEAK_SYMBOLS /* musl libc, FreeBSD, NetBSD, OpenBSD, Haiku */

     /* Avoid the need to link with '-lpthread'.  */

#    pragma weak pthread_mutex_lock

#    pragma weak pthread_mutex_unlock

     /* Determine whether libpthread is in use.  */

#    pragma weak pthread_mutexattr_gettype

     /* See the comments in lock.h.  */

#    define pthread_in_use() \

       (pthread_mutexattr_gettype != NULL || c11_threads_in_use ())

#   else

#    define pthread_in_use() 1

#   endif

static char *

nl_langinfo_with_lock (nl_item item)

{

  if (pthread_in_use())

    {

      pthread_mutex_t *lock = gl_get_nl_langinfo_lock ();

      if (pthread_mutex_lock (lock))

        abort ();

      char *ret = nl_langinfo_unlocked (item);

      if (pthread_mutex_unlock (lock))

        abort ();

      return ret;

    }

  else

    return nl_langinfo_unlocked (item);

}

#  elif HAVE_THREADS_H

extern mtx_t *gl_get_nl_langinfo_lock (void);

static char *

nl_langinfo_with_lock (nl_item item)

{

  mtx_t *lock = gl_get_nl_langinfo_lock ();

  if (mtx_lock (lock) != thrd_success)

    abort ();

  char *ret = nl_langinfo_unlocked (item);

  if (mtx_unlock (lock) != thrd_success)

    abort ();

  return ret;

}

#  endif

# else

/* On other platforms, no lock is needed.  */

#  define nl_langinfo_with_lock nl_langinfo

# endif

char *

rpl_nl_langinfo (nl_item item)

{

  switch (item)

    {

# if GNULIB_defined_CODESET

    case CODESET:

      return ctype_codeset ();

# endif

# if GNULIB_defined_ALTMON

    case ALTMON_1:

    case ALTMON_2:

    case ALTMON_3:

    case ALTMON_4:

    case ALTMON_5:

    case ALTMON_6:

    case ALTMON_7:

    case ALTMON_8:

    case ALTMON_9:

    case ALTMON_10:

    case ALTMON_11:

    case ALTMON_12:

      /* We don't ship the appropriate localizations with gnulib.  Therefore,

         treat ALTMON_i like MON_i.  */

      item = item - ALTMON_1 + MON_1;

      break;

# endif

# if GNULIB_defined_ABALTMON

    case ABALTMON_1:

    case ABALTMON_2:

    case ABALTMON_3:

    case ABALTMON_4:

    case ABALTMON_5:

    case ABALTMON_6:

    case ABALTMON_7:

    case ABALTMON_8:

    case ABALTMON_9:

    case ABALTMON_10:

    case ABALTMON_11:

    case ABALTMON_12:

      /* We don't ship the appropriate localizations with gnulib.  Therefore,

         treat ABALTMON_i like ABMON_i.  */

      item = item - ABALTMON_1 + ABMON_1;

      break;

# endif

# if GNULIB_defined_ERA

    case ERA:

      /* The format is not standardized.  In glibc it is a sequence of strings

         of the form "direction:offset:start_date:end_date:era_name:era_format"

         with an empty string at the end.  */

      return (char *) "";

    case ERA_D_FMT:

      /* The %Ex conversion in strftime behaves like %x if the locale does not

         have an alternative time format.  */

      item = D_FMT;

      break;

    case ERA_D_T_FMT:

      /* The %Ec conversion in strftime behaves like %c if the locale does not

         have an alternative time format.  */

      item = D_T_FMT;

      break;

    case ERA_T_FMT:

      /* The %EX conversion in strftime behaves like %X if the locale does not

         have an alternative time format.  */

      item = T_FMT;

      break;

    case ALT_DIGITS:

      /* The format is not standardized.  In glibc it is a sequence of 10

         strings, appended in memory.  */

      return (char *) "\0\0\0\0\0\0\0\0\0\0";

# endif

    default:

      break;

    }

  return nl_langinfo_with_lock (item);

}

#else

/* Provide nl_langinfo from scratch, either for native MS-Windows, or

   for old Unix platforms without locales, such as Linux libc5 or

   BeOS.  */

# include <time.h>

char *

nl_langinfo (nl_item item)

{

  char buf[100];

  struct tm tmm = { 0 };

  switch (item)

    {

    /* nl_langinfo items of the LC_CTYPE category */

    case CODESET:

      {

        char *codeset = ctype_codeset ();

        if (*codeset)

          return codeset;

      }

# ifdef __BEOS__

      return (char *) "UTF-8";

# else

      return (char *) "ISO-8859-1";

# endif

    /* nl_langinfo items of the LC_NUMERIC category */

    case RADIXCHAR:

      return localeconv () ->decimal_point;

    case THOUSEP:

      return localeconv () ->thousands_sep;

# ifdef GROUPING

    case GROUPING:

      return localeconv () ->grouping;

# endif

    /* nl_langinfo items of the LC_TIME category.

       TODO: Really use the locale.  */

    case D_T_FMT:

    case ERA_D_T_FMT:

      return (char *) "%a %b %e %H:%M:%S %Y";

    case D_FMT:

    case ERA_D_FMT:

      return (char *) "%m/%d/%y";

    case T_FMT:

    case ERA_T_FMT:

      return (char *) "%H:%M:%S";

    case T_FMT_AMPM:

      return (char *) "%I:%M:%S %p";

    case AM_STR:

      {

        static char result[80];

        if (!strftime (buf, sizeof result, "%p", &tmm))

          return (char *) "AM";

        strcpy (result, buf);

        return result;

      }

    case PM_STR:

      {

        static char result[80];

        tmm.tm_hour = 12;

        if (!strftime (buf, sizeof result, "%p", &tmm))

          return (char *) "PM";

        strcpy (result, buf);

        return result;

      }

    case DAY_1:

    case DAY_2:

    case DAY_3:

    case DAY_4:

    case DAY_5:

    case DAY_6:

    case DAY_7:

      {

        static char result[7][50];

        static char const days[][sizeof "Wednesday"] = {

          "Sunday", "Monday", "Tuesday", "Wednesday", "Thursday",

          "Friday", "Saturday"

        };

        tmm.tm_wday = item - DAY_1;

        if (!strftime (buf, sizeof result[0], "%A", &tmm))

          return (char *) days[item - DAY_1];

        strcpy (result[item - DAY_1], buf);

        return result[item - DAY_1];

      }

    case ABDAY_1:

    case ABDAY_2:

    case ABDAY_3:

    case ABDAY_4:

    case ABDAY_5:

    case ABDAY_6:

    case ABDAY_7:

      {

        static char result[7][30];

        static char const abdays[][sizeof "Sun"] = {

          "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"

        };

        tmm.tm_wday = item - ABDAY_1;

        if (!strftime (buf, sizeof result[0], "%a", &tmm))

          return (char *) abdays[item - ABDAY_1];

        strcpy (result[item - ABDAY_1], buf);

        return result[item - ABDAY_1];

      }

    {

      static char const months[][sizeof "September"] = {

        "January", "February", "March", "April", "May", "June", "July",

        "August", "September", "October", "November", "December"

      };

      case MON_1:

      case MON_2:

      case MON_3:

      case MON_4:

      case MON_5:

      case MON_6:

      case MON_7:

      case MON_8:

      case MON_9:

      case MON_10:

      case MON_11:

      case MON_12:

        {

          static char result[12][50];

          tmm.tm_mon = item - MON_1;

          if (!strftime (buf, sizeof result[0], "%B", &tmm))

            return (char *) months[item - MON_1];

          strcpy (result[item - MON_1], buf);

          return result[item - MON_1];

        }

      case ALTMON_1:

      case ALTMON_2:

      case ALTMON_3:

      case ALTMON_4:

      case ALTMON_5:

      case ALTMON_6:

      case ALTMON_7:

      case ALTMON_8:

      case ALTMON_9:

      case ALTMON_10:

      case ALTMON_11:

      case ALTMON_12:

        {

          static char result[12][50];

          tmm.tm_mon = item - ALTMON_1;

          /* The platforms without nl_langinfo() don't support strftime with

             %OB.  We don't even need to try.  */

          #if 0

          if (!strftime (buf, sizeof result[0], "%OB", &tmm))

          #endif

            if (!strftime (buf, sizeof result[0], "%B", &tmm))

              return (char *) months[item - ALTMON_1];

          strcpy (result[item - ALTMON_1], buf);

          return result[item - ALTMON_1];

        }

    }

    {

      static char const abmonths[][sizeof "Jan"] = {

        "Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul",

        "Aug", "Sep", "Oct", "Nov", "Dec"

      };

      case ABMON_1:

      case ABMON_2:

      case ABMON_3:

      case ABMON_4:

      case ABMON_5:

      case ABMON_6:

      case ABMON_7:

      case ABMON_8:

      case ABMON_9:

      case ABMON_10:

      case ABMON_11:

      case ABMON_12:

        {

          static char result[12][30];

          tmm.tm_mon = item - ABMON_1;

          if (!strftime (buf, sizeof result[0], "%b", &tmm))

            return (char *) abmonths[item - ABMON_1];

          strcpy (result[item - ABMON_1], buf);

          return result[item - ABMON_1];

        }

      case ABALTMON_1:

      case ABALTMON_2:

      case ABALTMON_3:

      case ABALTMON_4:

      case ABALTMON_5:

      case ABALTMON_6:

      case ABALTMON_7:

      case ABALTMON_8:

      case ABALTMON_9:

      case ABALTMON_10:

      case ABALTMON_11:

      case ABALTMON_12:

        {

          static char result[12][50];

          tmm.tm_mon = item - ABALTMON_1;

          /* The platforms without nl_langinfo() don't support strftime with

             %Ob.  We don't even need to try.  */

          #if 0

          if (!strftime (buf, sizeof result[0], "%Ob", &tmm))

          #endif

            if (!strftime (buf, sizeof result[0], "%b", &tmm))

              return (char *) abmonths[item - ABALTMON_1];

          strcpy (result[item - ABALTMON_1], buf);

          return result[item - ABALTMON_1];

        }

    }

    case ERA:

      return (char *) "";

    case ALT_DIGITS:

      return (char *) "\0\0\0\0\0\0\0\0\0\0";

    /* nl_langinfo items of the LC_MONETARY category.  */

    case CRNCYSTR:

      return localeconv () ->currency_symbol;

# ifdef INT_CURR_SYMBOL

    case INT_CURR_SYMBOL:

      return localeconv () ->int_curr_symbol;

    case MON_DECIMAL_POINT:

      return localeconv () ->mon_decimal_point;

    case MON_THOUSANDS_SEP:

      return localeconv () ->mon_thousands_sep;

    case MON_GROUPING:

      return localeconv () ->mon_grouping;

    case POSITIVE_SIGN:

      return localeconv () ->positive_sign;

    case NEGATIVE_SIGN:

      return localeconv () ->negative_sign;

    case FRAC_DIGITS:

      return & localeconv () ->frac_digits;

    case INT_FRAC_DIGITS:

      return & localeconv () ->int_frac_digits;

    case P_CS_PRECEDES:

      return & localeconv () ->p_cs_precedes;

    case N_CS_PRECEDES:

      return & localeconv () ->n_cs_precedes;

    case P_SEP_BY_SPACE:

      return & localeconv () ->p_sep_by_space;

    case N_SEP_BY_SPACE:

      return & localeconv () ->n_sep_by_space;

    case P_SIGN_POSN:

      return & localeconv () ->p_sign_posn;

    case N_SIGN_POSN:

      return & localeconv () ->n_sign_posn;

# endif

    /* nl_langinfo items of the LC_MESSAGES category

       TODO: Really use the locale. */

    case YESEXPR:

      return (char *) "^[yY]";

    case NOEXPR:

      return (char *) "^[nN]";

    default:

      return (char *) "";

    }

}

#endif