/* Copyright (C) 1991-2017 Free Software Foundation, Inc.

   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or

   modify it under the terms of the GNU General Public

   License as published by the Free Software Foundation; either

   version 3 of the License, or (at your option) any later version.

   The GNU C Library 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

   General Public License for more details.

   You should have received a copy of the GNU General Public

   License along with the GNU C Library; if not, see

   <http://www.gnu.org/licenses/>.  */

#ifdef _LIBC

# define USE_IN_EXTENDED_LOCALE_MODEL 1

# define HAVE_STRUCT_ERA_ENTRY 1

# define HAVE_TM_GMTOFF 1

# define HAVE_TM_ZONE 1

# define HAVE_TZNAME 1

# define HAVE_TZSET 1

# include "../locale/localeinfo.h"

#else

# include <config.h>

# if FPRINTFTIME

#  include "fprintftime.h"

# else

#  include "strftime.h"

# endif

# include "time-internal.h"

#endif

#include <ctype.h>

#include <time.h>

#if HAVE_TZNAME && !HAVE_DECL_TZNAME

extern char *tzname[];

#endif

/* Do multibyte processing if multibyte encodings are supported, unless

   multibyte sequences are safe in formats.  Multibyte sequences are

   safe if they cannot contain byte sequences that look like format

   conversion specifications.  The multibyte encodings used by the

   C library on the various platforms (UTF-8, GB2312, GBK, CP936,

   GB18030, EUC-TW, BIG5, BIG5-HKSCS, CP950, EUC-JP, EUC-KR, CP949,

   SHIFT_JIS, CP932, JOHAB) are safe for formats, because the byte '%'

   cannot occur in a multibyte character except in the first byte.

   The DEC-HANYU encoding used on OSF/1 is not safe for formats, but

   this encoding has never been seen in real-life use, so we ignore

   it.  */

#if !(defined __osf__ && 0)

# define MULTIBYTE_IS_FORMAT_SAFE 1

#endif

#define DO_MULTIBYTE (! MULTIBYTE_IS_FORMAT_SAFE)

#if DO_MULTIBYTE

# include <wchar.h>

  static const mbstate_t mbstate_zero;

#endif

#include <limits.h>

#include <stddef.h>

#include <stdlib.h>

#include <string.h>

#include <stdbool.h>

#ifndef FALLTHROUGH

# if __GNUC__ < 7

#  define FALLTHROUGH ((void) 0)

# else

#  define FALLTHROUGH __attribute__ ((__fallthrough__))

# endif

#endif

#ifdef COMPILE_WIDE

# include <endian.h>

# define CHAR_T wchar_t

# define UCHAR_T unsigned int

# define L_(Str) L##Str

# define NLW(Sym) _NL_W##Sym

# define MEMCPY(d, s, n) __wmemcpy (d, s, n)

# define STRLEN(s) __wcslen (s)

#else

# define CHAR_T char

# define UCHAR_T unsigned char

# define L_(Str) Str

# define NLW(Sym) Sym

# define MEMCPY(d, s, n) memcpy (d, s, n)

# define STRLEN(s) strlen (s)

#endif

/* Shift A right by B bits portably, by dividing A by 2**B and

   truncating towards minus infinity.  A and B should be free of side

   effects, and B should be in the range 0 <= B <= INT_BITS - 2, where

   INT_BITS is the number of useful bits in an int.  GNU code can

   assume that INT_BITS is at least 32.

   ISO C99 says that A >> B is implementation-defined if A < 0.  Some

   implementations (e.g., UNICOS 9.0 on a Cray Y-MP EL) don't shift

   right in the usual way when A < 0, so SHR falls back on division if

   ordinary A >> B doesn't seem to be the usual signed shift.  */

#define SHR(a, b)       \

  (-1 >> 1 == -1        \

   ? (a) >> (b)         \

   : (a) / (1 << (b)) - ((a) % (1 << (b)) < 0))

/* Bound on length of the string representing an integer type or expression T.

   Subtract 1 for the sign bit if t is signed; log10 (2.0) < 146/485;

   add 1 for integer division truncation; add 1 more for a minus sign

   if needed.  */

#define INT_STRLEN_BOUND(t) \

  ((sizeof (t) * CHAR_BIT - 1) * 146 / 485 + 2)

#define TM_YEAR_BASE 1900

#ifndef __isleap

/* Nonzero if YEAR is a leap year (every 4 years,

   except every 100th isn't, and every 400th is).  */

# define __isleap(year) \

  ((year) % 4 == 0 && ((year) % 100 != 0 || (year) % 400 == 0))

#endif

#ifdef _LIBC

# define mktime_z(tz, tm) mktime (tm)

# define tzname __tzname

# define tzset __tzset

#endif

#ifndef FPRINTFTIME

# define FPRINTFTIME 0

#endif

#if FPRINTFTIME

# define STREAM_OR_CHAR_T FILE

# define STRFTIME_ARG(x) /* empty */

#else

# define STREAM_OR_CHAR_T CHAR_T

# define STRFTIME_ARG(x) x,

#endif

#if FPRINTFTIME

# define memset_byte(P, Len, Byte) \

  do { size_t _i; for (_i = 0; _i < Len; _i++) fputc (Byte, P); } while (0)

# define memset_space(P, Len) memset_byte (P, Len, ' ')

# define memset_zero(P, Len) memset_byte (P, Len, '0')

#elif defined COMPILE_WIDE

# define memset_space(P, Len) (wmemset (P, L' ', Len), (P) += (Len))

# define memset_zero(P, Len) (wmemset (P, L'0', Len), (P) += (Len))

#else

# define memset_space(P, Len) (memset (P, ' ', Len), (P) += (Len))

# define memset_zero(P, Len) (memset (P, '0', Len), (P) += (Len))

#endif

#if FPRINTFTIME

# define advance(P, N)

#else

# define advance(P, N) ((P) += (N))

#endif

#define add(n, f)                                                             \

  do                                                                          \

    {                                                                         \

      size_t _n = (n);                                                        \

      size_t _w = (width < 0 ? 0 : width);                                    \

      size_t _incr = _n < _w ? _w : _n;                                       \

      if (_incr >= maxsize - i)                                               \

        return 0;                                                             \

      if (p)                                                                  \

        {                                                                     \

          if (digits == 0 && _n < _w)                                         \

            {                                                                 \

              size_t _delta = width - _n;                                     \

              if (pad == L_('0'))                                             \

                memset_zero (p, _delta);                                      \

              else                                                            \

                memset_space (p, _delta);                                     \

            }                                                                 \

          f;                                                                  \

          advance (p, _n);                                                    \

        }                                                                     \

      i += _incr;                                                             \

    } while (0)

#if FPRINTFTIME

# define add1(C) add (1, fputc (C, p))

#else

# define add1(C) add (1, *p = C)

#endif

#if FPRINTFTIME

# define cpy(n, s) \

    add ((n),                                                                 \

     do                                                                       \

       {                                                                      \

         if (to_lowcase)                                                      \

           fwrite_lowcase (p, (s), _n);                                       \

         else if (to_uppcase)                                                 \

           fwrite_uppcase (p, (s), _n);                                       \

         else                                                                 \

           {                                                                  \

             /* Ignore the value of fwrite.  The caller can determine whether \

                an error occurred by inspecting ferror (P).  All known fwrite \

                implementations set the stream's error indicator when they    \

                fail due to ENOMEM etc., even though C11 and POSIX.1-2008 do  \

                not require this.  */                                         \

             fwrite (s, _n, 1, p);                                            \

           }                                                                  \

       }                                                                      \

     while (0)                                                                \

    )

#else

# define cpy(n, s)                                                            \

    add ((n),                                                                 \

         if (to_lowcase)                                                      \

           memcpy_lowcase (p, (s), _n LOCALE_ARG);                            \

         else if (to_uppcase)                                                 \

           memcpy_uppcase (p, (s), _n LOCALE_ARG);                            \

         else                                                                 \

           MEMCPY ((void *) p, (void const *) (s), _n))

#endif

#ifdef COMPILE_WIDE

# ifndef USE_IN_EXTENDED_LOCALE_MODEL

#  undef __mbsrtowcs_l

#  define __mbsrtowcs_l(d, s, l, st, loc) __mbsrtowcs (d, s, l, st)

# endif

# define widen(os, ws, l) \

  {                                                                           \

    mbstate_t __st;                                                           \

    const char *__s = os;                                                     \

    memset (&__st, '\0', sizeof (__st));                                      \

    l = __mbsrtowcs_l (NULL, &__s, 0, &__st, loc);                            \

    ws = (wchar_t *) alloca ((l + 1) * sizeof (wchar_t));                     \

    (void) __mbsrtowcs_l (ws, &__s, l, &__st, loc);                           \

  }

#endif

#if defined _LIBC && defined USE_IN_EXTENDED_LOCALE_MODEL

/* We use this code also for the extended locale handling where the

   function gets as an additional argument the locale which has to be

   used.  To access the values we have to redefine the _NL_CURRENT

   macro.  */

# define strftime               __strftime_l

# define wcsftime               __wcsftime_l

# undef _NL_CURRENT

# define _NL_CURRENT(category, item) \

  (current->values[_NL_ITEM_INDEX (item)].string)

# define LOCALE_PARAM , __locale_t loc

# define LOCALE_ARG , loc

# define HELPER_LOCALE_ARG  , current

#else

# define LOCALE_PARAM

# define LOCALE_ARG

# ifdef _LIBC

#  define HELPER_LOCALE_ARG , _NL_CURRENT_DATA (LC_TIME)

# else

#  define HELPER_LOCALE_ARG

# endif

#endif

#ifdef COMPILE_WIDE

# ifdef USE_IN_EXTENDED_LOCALE_MODEL

#  define TOUPPER(Ch, L) __towupper_l (Ch, L)

#  define TOLOWER(Ch, L) __towlower_l (Ch, L)

# else

#  define TOUPPER(Ch, L) towupper (Ch)

#  define TOLOWER(Ch, L) towlower (Ch)

# endif

#else

# ifdef USE_IN_EXTENDED_LOCALE_MODEL

#  define TOUPPER(Ch, L) __toupper_l (Ch, L)

#  define TOLOWER(Ch, L) __tolower_l (Ch, L)

# else

#  define TOUPPER(Ch, L) toupper (Ch)

#  define TOLOWER(Ch, L) tolower (Ch)

# endif

#endif

/* We don't use 'isdigit' here since the locale dependent

   interpretation is not what we want here.  We only need to accept

   the arabic digits in the ASCII range.  One day there is perhaps a

   more reliable way to accept other sets of digits.  */

#define ISDIGIT(Ch) ((unsigned int) (Ch) - L_('0') <= 9)

#if FPRINTFTIME

static void

fwrite_lowcase (FILE *fp, const CHAR_T *src, size_t len)

{

  while (len-- > 0)

    {

      fputc (TOLOWER ((UCHAR_T) *src, loc), fp);

      ++src;

    }

}

static void

fwrite_uppcase (FILE *fp, const CHAR_T *src, size_t len)

{

  while (len-- > 0)

    {

      fputc (TOUPPER ((UCHAR_T) *src, loc), fp);

      ++src;

    }

}

#else

static CHAR_T *memcpy_lowcase (CHAR_T *dest, const CHAR_T *src,

                               size_t len LOCALE_PARAM);

static CHAR_T *

memcpy_lowcase (CHAR_T *dest, const CHAR_T *src, size_t len LOCALE_PARAM)

{

  while (len-- > 0)

    dest[len] = TOLOWER ((UCHAR_T) src[len], loc);

  return dest;

}

static CHAR_T *memcpy_uppcase (CHAR_T *dest, const CHAR_T *src,

                               size_t len LOCALE_PARAM);

static CHAR_T *

memcpy_uppcase (CHAR_T *dest, const CHAR_T *src, size_t len LOCALE_PARAM)

{

  while (len-- > 0)

    dest[len] = TOUPPER ((UCHAR_T) src[len], loc);

  return dest;

}

#endif

#if ! HAVE_TM_GMTOFF

/* Yield the difference between *A and *B,

   measured in seconds, ignoring leap seconds.  */

# define tm_diff ftime_tm_diff

static int tm_diff (const struct tm *, const struct tm *);

static int

tm_diff (const struct tm *a, const struct tm *b)

{

  /* Compute intervening leap days correctly even if year is negative.

     Take care to avoid int overflow in leap day calculations,

     but it's OK to assume that A and B are close to each other.  */

  int a4 = SHR (a->tm_year, 2) + SHR (TM_YEAR_BASE, 2) - ! (a->tm_year & 3);

  int b4 = SHR (b->tm_year, 2) + SHR (TM_YEAR_BASE, 2) - ! (b->tm_year & 3);

  int a100 = a4 / 25 - (a4 % 25 < 0);

  int b100 = b4 / 25 - (b4 % 25 < 0);

  int a400 = SHR (a100, 2);

  int b400 = SHR (b100, 2);

  int intervening_leap_days = (a4 - b4) - (a100 - b100) + (a400 - b400);

  int years = a->tm_year - b->tm_year;

  int days = (365 * years + intervening_leap_days

              + (a->tm_yday - b->tm_yday));

  return (60 * (60 * (24 * days + (a->tm_hour - b->tm_hour))

                + (a->tm_min - b->tm_min))

          + (a->tm_sec - b->tm_sec));

}

#endif /* ! HAVE_TM_GMTOFF */

/* The number of days from the first day of the first ISO week of this

   year to the year day YDAY with week day WDAY.  ISO weeks start on

   Monday; the first ISO week has the year's first Thursday.  YDAY may

   be as small as YDAY_MINIMUM.  */

#define ISO_WEEK_START_WDAY 1 /* Monday */

#define ISO_WEEK1_WDAY 4 /* Thursday */

#define YDAY_MINIMUM (-366)

static int iso_week_days (int, int);

#ifdef __GNUC__

__inline__

#endif

static int

iso_week_days (int yday, int wday)

{

  /* Add enough to the first operand of % to make it nonnegative.  */

  int big_enough_multiple_of_7 = (-YDAY_MINIMUM / 7 + 2) * 7;

  return (yday

          - (yday - wday + ISO_WEEK1_WDAY + big_enough_multiple_of_7) % 7

          + ISO_WEEK1_WDAY - ISO_WEEK_START_WDAY);

}

/* When compiling this file, GNU applications can #define my_strftime

   to a symbol (typically nstrftime) to get an extended strftime with

   extra arguments TZ and NS.  */

#if FPRINTFTIME

# undef my_strftime

# define my_strftime fprintftime

#endif

#ifdef my_strftime

# undef HAVE_TZSET

# define extra_args , tz, ns

# define extra_args_spec , timezone_t tz, int ns

#else

# if defined COMPILE_WIDE

#  define my_strftime wcsftime

#  define nl_get_alt_digit _nl_get_walt_digit

# else

#  define my_strftime strftime

#  define nl_get_alt_digit _nl_get_alt_digit

# endif

# define extra_args

# define extra_args_spec

/* We don't have this information in general.  */

# define tz 1

# define ns 0

#endif

static size_t __strftime_internal (STREAM_OR_CHAR_T *, STRFTIME_ARG (size_t)

                                   const CHAR_T *, const struct tm *,

                                   bool, bool *

                                   extra_args_spec LOCALE_PARAM);

/* Write information from TP into S according to the format

   string FORMAT, writing no more that MAXSIZE characters

   (including the terminating '\0') and returning number of

   characters written.  If S is NULL, nothing will be written

   anywhere, so to determine how many characters would be

   written, use NULL for S and (size_t) -1 for MAXSIZE.  */

size_t

my_strftime (STREAM_OR_CHAR_T *s, STRFTIME_ARG (size_t maxsize)

             const CHAR_T *format,

             const struct tm *tp extra_args_spec LOCALE_PARAM)

{

  bool tzset_called = false;

  return __strftime_internal (s, STRFTIME_ARG (maxsize) format, tp,

                              false, &tzset_called extra_args LOCALE_ARG);

}

#if defined _LIBC && ! FPRINTFTIME

libc_hidden_def (my_strftime)

#endif

/* Just like my_strftime, above, but with two more parameters.

   UPCASE indicate that the result should be converted to upper case,

   and *TZSET_CALLED indicates whether tzset has been called here.  */

static size_t

__strftime_internal (STREAM_OR_CHAR_T *s, STRFTIME_ARG (size_t maxsize)

                     const CHAR_T *format,

                     const struct tm *tp, bool upcase, bool *tzset_called

                     extra_args_spec LOCALE_PARAM)

{

#if defined _LIBC && defined USE_IN_EXTENDED_LOCALE_MODEL

  struct __locale_data *const current = loc->__locales[LC_TIME];

#endif

#if FPRINTFTIME

  size_t maxsize = (size_t) -1;

#endif

  int hour12 = tp->tm_hour;

#ifdef _NL_CURRENT

  /* We cannot make the following values variables since we must delay

     the evaluation of these values until really needed since some

     expressions might not be valid in every situation.  The 'struct tm'

     might be generated by a strptime() call that initialized

     only a few elements.  Dereference the pointers only if the format

     requires this.  Then it is ok to fail if the pointers are invalid.  */

# define a_wkday \

  ((const CHAR_T *) (tp->tm_wday < 0 || tp->tm_wday > 6                      \

                     ? "?" : _NL_CURRENT (LC_TIME, NLW(ABDAY_1) + tp->tm_wday)))

# define f_wkday \

  ((const CHAR_T *) (tp->tm_wday < 0 || tp->tm_wday > 6                      \

                     ? "?" : _NL_CURRENT (LC_TIME, NLW(DAY_1) + tp->tm_wday)))

# define a_month \

  ((const CHAR_T *) (tp->tm_mon < 0 || tp->tm_mon > 11                       \

                     ? "?" : _NL_CURRENT (LC_TIME, NLW(ABMON_1) + tp->tm_mon)))

# define f_month \

  ((const CHAR_T *) (tp->tm_mon < 0 || tp->tm_mon > 11                       \

                     ? "?" : _NL_CURRENT (LC_TIME, NLW(MON_1) + tp->tm_mon)))

# define ampm \

  ((const CHAR_T *) _NL_CURRENT (LC_TIME, tp->tm_hour > 11                    \

                                 ? NLW(PM_STR) : NLW(AM_STR)))

# define aw_len STRLEN (a_wkday)

# define am_len STRLEN (a_month)

# define ap_len STRLEN (ampm)

#endif

#if HAVE_TZNAME

  char **tzname_vec = tzname;

#endif

  const char *zone;

  size_t i = 0;

  STREAM_OR_CHAR_T *p = s;

  const CHAR_T *f;

#if DO_MULTIBYTE && !defined COMPILE_WIDE

  const char *format_end = NULL;

#endif

#if ! defined _LIBC && ! HAVE_RUN_TZSET_TEST

  /* Solaris 2.5.x and 2.6 tzset sometimes modify the storage returned

     by localtime.  On such systems, we must either use the tzset and

     localtime wrappers to work around the bug (which sets

     HAVE_RUN_TZSET_TEST) or make a copy of the structure.  */

  struct tm copy = *tp;

  tp = ©

#endif

  zone = NULL;

#if HAVE_TM_ZONE

  /* The POSIX test suite assumes that setting

     the environment variable TZ to a new value before calling strftime()

     will influence the result (the %Z format) even if the information in

     TP is computed with a totally different time zone.

     This is bogus: though POSIX allows bad behavior like this,

     POSIX does not require it.  Do the right thing instead.  */

  zone = (const char *) tp->tm_zone;

#endif

#if HAVE_TZNAME

  if (!tz)

    {

      if (! (zone && *zone))

        zone = "GMT";

    }

  else

    {

# if !HAVE_TM_ZONE

      /* Infer the zone name from *TZ instead of from TZNAME.  */

      tzname_vec = tz->tzname_copy;

# endif

    }

  /* The tzset() call might have changed the value.  */

  if (!(zone && *zone) && tp->tm_isdst >= 0)

    {

      /* POSIX.1 requires that local time zone information be used as

         though strftime called tzset.  */

# if HAVE_TZSET

      if (!*tzset_called)

        {

          tzset ();

          *tzset_called = true;

        }

# endif

      zone = tzname_vec[tp->tm_isdst != 0];

    }

#endif

  if (! zone)

    zone = "";

  if (hour12 > 12)

    hour12 -= 12;

  else

    if (hour12 == 0)

      hour12 = 12;

  for (f = format; *f != '\0'; ++f)

    {

      int pad = 0;              /* Padding for number ('-', '_', or 0).  */

      int modifier;             /* Field modifier ('E', 'O', or 0).  */

      int digits = 0;           /* Max digits for numeric format.  */

      int number_value;         /* Numeric value to be printed.  */

      unsigned int u_number_value; /* (unsigned int) number_value.  */

      bool negative_number;     /* The number is negative.  */

      bool always_output_a_sign; /* +/- should always be output.  */

      int tz_colon_mask;        /* Bitmask of where ':' should appear.  */

      const CHAR_T *subfmt;

      CHAR_T sign_char;

      CHAR_T *bufp;

      CHAR_T buf[1

                 + 2 /* for the two colons in a %::z or %:::z time zone */

                 + (sizeof (int) < sizeof (time_t)

                    ? INT_STRLEN_BOUND (time_t)

                    : INT_STRLEN_BOUND (int))];

      int width = -1;

      bool to_lowcase = false;

      bool to_uppcase = upcase;

      size_t colons;

      bool change_case = false;

      int format_char;

#if DO_MULTIBYTE && !defined COMPILE_WIDE

      switch (*f)

        {

        case L_('%'):

          break;

        case L_('\b'): case L_('\t'): case L_('\n'):

        case L_('\v'): case L_('\f'): case L_('\r'):

        case L_(' '): case L_('!'): case L_('"'): case L_('#'): case L_('&'):

        case L_('\''): case L_('('): case L_(')'): case L_('*'): case L_('+'):

        case L_(','): case L_('-'): case L_('.'): case L_('/'): case L_('0'):

        case L_('1'): case L_('2'): case L_('3'): case L_('4'): case L_('5'):

        case L_('6'): case L_('7'): case L_('8'): case L_('9'): case L_(':'):

        case L_(';'): case L_('<'): case L_('='): case L_('>'): case L_('?'):

        case L_('A'): case L_('B'): case L_('C'): case L_('D'): case L_('E'):

        case L_('F'): case L_('G'): case L_('H'): case L_('I'): case L_('J'):

        case L_('K'): case L_('L'): case L_('M'): case L_('N'): case L_('O'):

        case L_('P'): case L_('Q'): case L_('R'): case L_('S'): case L_('T'):

        case L_('U'): case L_('V'): case L_('W'): case L_('X'): case L_('Y'):

        case L_('Z'): case L_('['): case L_('\\'): case L_(']'): case L_('^'):

        case L_('_'): case L_('a'): case L_('b'): case L_('c'): case L_('d'):

        case L_('e'): case L_('f'): case L_('g'): case L_('h'): case L_('i'):

        case L_('j'): case L_('k'): case L_('l'): case L_('m'): case L_('n'):

        case L_('o'): case L_('p'): case L_('q'): case L_('r'): case L_('s'):

        case L_('t'): case L_('u'): case L_('v'): case L_('w'): case L_('x'):

        case L_('y'): case L_('z'): case L_('{'): case L_('|'): case L_('}'):

        case L_('~'):

          /* The C Standard requires these 98 characters (plus '%') to

             be in the basic execution character set.  None of these

             characters can start a multibyte sequence, so they need

             not be analyzed further.  */

          add1 (*f);

          continue;

        default:

          /* Copy this multibyte sequence until we reach its end, find

             an error, or come back to the initial shift state.  */

          {

            mbstate_t mbstate = mbstate_zero;

            size_t len = 0;

            size_t fsize;

            if (! format_end)

              format_end = f + strlen (f) + 1;

            fsize = format_end - f;

            do

              {

                size_t bytes = mbrlen (f + len, fsize - len, &mbstate);

                if (bytes == 0)

                  break;

                if (bytes == (size_t) -2)

                  {

                    len += strlen (f + len);

                    break;

                  }

                if (bytes == (size_t) -1)

                  {

                    len++;

                    break;

                  }

                len += bytes;

              }

            while (! mbsinit (&mbstate));

            cpy (len, f);

            f += len - 1;

            continue;

          }

        }

#else /* ! DO_MULTIBYTE */

      /* Either multibyte encodings are not supported, they are

         safe for formats, so any non-'%' byte can be copied through,

         or this is the wide character version.  */

      if (*f != L_('%'))

        {

          add1 (*f);

          continue;

        }

#endif /* ! DO_MULTIBYTE */

      /* Check for flags that can modify a format.  */

      while (1)

        {

          switch (*++f)

            {

              /* This influences the number formats.  */

            case L_('_'):

            case L_('-'):

            case L_('0'):

              pad = *f;

              continue;

              /* This changes textual output.  */

            case L_('^'):

              to_uppcase = true;

              continue;

            case L_('#'):

              change_case = true;

              continue;

            default:

              break;

            }

          break;

        }

      /* As a GNU extension we allow the field width to be specified.  */

      if (ISDIGIT (*f))

        {

          width = 0;

          do

            {

              if (width > INT_MAX / 10

                  || (width == INT_MAX / 10 && *f - L_('0') > INT_MAX % 10))

                /* Avoid overflow.  */

                width = INT_MAX;

              else

                {

                  width *= 10;

                  width += *f - L_('0');

                }

              ++f;

            }

          while (ISDIGIT (*f));

        }

      /* Check for modifiers.  */

      switch (*f)

        {

        case L_('E'):

        case L_('O'):

          modifier = *f++;

          break;

        default:

          modifier = 0;

          break;

        }

      /* Now do the specified format.  */

      format_char = *f;

      switch (format_char)

        {

#define DO_NUMBER(d, v) \

          do                                                                  \

            {                                                                 \

              digits = d;                                                     \

              number_value = v;                                               \

              goto do_number;                                                 \

            }                                                                 \

          while (0)

#define DO_SIGNED_NUMBER(d, negative, v) \

          do                                                                  \

            {                                                                 \

              digits = d;                                                     \

              negative_number = negative;                                     \

              u_number_value = v;                                             \

              goto do_signed_number;                                          \

            }                                                                 \

          while (0)

          /* The mask is not what you might think.

             When the ordinal i'th bit is set, insert a colon

             before the i'th digit of the time zone representation.  */

#define DO_TZ_OFFSET(d, mask, v) \

          do                                                                  \

            {                                                                 \

              digits = d;                                                     \

              tz_colon_mask = mask;                                           \

              u_number_value = v;                                             \

              goto do_tz_offset;                                              \

            }                                                                 \

          while (0)

#define DO_NUMBER_SPACEPAD(d, v) \

          do                                                                  \

            {                                                                 \

              digits = d;                                                     \

              number_value = v;                                               \

              goto do_number_spacepad;                                        \

            }                                                                 \

          while (0)

        case L_('%'):

          if (modifier != 0)

            goto bad_format;

          add1 (*f);

          break;

        case L_('a'):

          if (modifier != 0)

            goto bad_format;

          if (change_case)

            {

              to_uppcase = true;

              to_lowcase = false;

            }

#ifdef _NL_CURRENT

          cpy (aw_len, a_wkday);

          break;

#else

          goto underlying_strftime;

#endif

        case 'A':

          if (modifier != 0)

            goto bad_format;

          if (change_case)

            {

              to_uppcase = true;

              to_lowcase = false;

            }

#ifdef _NL_CURRENT

          cpy (STRLEN (f_wkday), f_wkday);

          break;

#else

          goto underlying_strftime;

#endif

        case L_('b'):

        case L_('h'):

          if (change_case)

            {

              to_uppcase = true;

              to_lowcase = false;

            }

          if (modifier != 0)

            goto bad_format;

#ifdef _NL_CURRENT

          cpy (am_len, a_month);

          break;

#else

          goto underlying_strftime;

#endif

        case L_('B'):

          if (modifier != 0)

            goto bad_format;

          if (change_case)

            {

              to_uppcase = true;

              to_lowcase = false;

            }

#ifdef _NL_CURRENT

          cpy (STRLEN (f_month), f_month);

          break;

#else

          goto underlying_strftime;

#endif

        case L_('c'):

          if (modifier == L_('O'))

            goto bad_format;

#ifdef _NL_CURRENT

          if (! (modifier == 'E'

                 && (*(subfmt =

                       (const CHAR_T *) _NL_CURRENT (LC_TIME,

                                                     NLW(ERA_D_T_FMT)))

                     != '\0')))

            subfmt = (const CHAR_T *) _NL_CURRENT (LC_TIME, NLW(D_T_FMT));

#else

          goto underlying_strftime;

#endif

        subformat:

          {

            size_t len = __strftime_internal (NULL, STRFTIME_ARG ((size_t) -1)

                                              subfmt,

                                              tp, to_uppcase, tzset_called

                                              extra_args LOCALE_ARG);

            add (len, __strftime_internal (p,

                                           STRFTIME_ARG (maxsize - i)

                                           subfmt,

                                           tp, to_uppcase, tzset_called

                                           extra_args LOCALE_ARG));

          }

          break;

#if !(defined _NL_CURRENT && HAVE_STRUCT_ERA_ENTRY)

        underlying_strftime:

          {

            /* The relevant information is available only via the

               underlying strftime implementation, so use that.  */

            char ufmt[5];

            char *u = ufmt;

            char ubuf[1024]; /* enough for any single format in practice */

            size_t len;

            /* Make sure we're calling the actual underlying strftime.

               In some cases, config.h contains something like

               "#define strftime rpl_strftime".  */

# ifdef strftime

#  undef strftime

            size_t strftime ();

# endif

            /* The space helps distinguish strftime failure from empty