/* Copyright (C) 1991-1999, 2000, 2001, 2002, 2003

   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 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.

   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

   Lesser General Public License for more details.

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

   License along with the GNU C Library; if not, write to the Free

   Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA

   02110-1301 USA.  */

#ifdef HAVE_CONFIG_H

# include <config.h>

#endif

#ifdef _LIBC

# define HAVE_LIMITS_H 1

# define HAVE_MBLEN 1

# define HAVE_MBRLEN 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

# define MULTIBYTE_IS_FORMAT_SAFE 1

# define STDC_HEADERS 1

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

#endif

#if defined emacs && !defined HAVE_BCOPY

# define HAVE_MEMCPY 1

#endif

#include <ctype.h>

#ifdef TIME_T_IN_SYS_TYPES

#include <sys/types.h>		/* Some systems define `time_t' here.  */

#endif

#ifdef TIME_WITH_SYS_TIME

# include <sys/time.h>

# include <time.h>

#else

# ifdef HAVE_SYS_TIME_H

#  include <sys/time.h>

# else

#  include <time.h>

# endif

#endif

#if HAVE_TZNAME

#ifndef __MINGW32__

extern char *tzname[];

#endif

#endif

/* Do multibyte processing if multibytes 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 GNU C Library uses UTF8 multibyte

   encoding, which is safe for formats, but strftime.c can be used

   with other C libraries that use unsafe encodings.  */

#define DO_MULTIBYTE (HAVE_MBLEN && ! MULTIBYTE_IS_FORMAT_SAFE)

#if DO_MULTIBYTE

# if HAVE_MBRLEN

#  include <wchar.h>

# else

   /* Simulate mbrlen with mblen as best we can.  */

#  define mbstate_t int

#  define mbrlen(s, n, ps) mblen (s, n)

#  define mbsinit(ps) (*(ps) == 0)

# endif

  static const mbstate_t mbstate_zero;

#endif

#if HAVE_LIMITS_H

# include <limits.h>

#endif

#if STDC_HEADERS

# include <stddef.h>

# include <stdlib.h>

# include <string.h>

#else

# ifndef HAVE_MEMCPY

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

# 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

# if !defined STDC_HEADERS && !defined HAVE_MEMCPY

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

# else

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

# endif

# define STRLEN(s) strlen (s)

# ifdef _LIBC

#  define MEMPCPY(d, s, n) __mempcpy (d, s, n)

# else

#  ifndef HAVE_MEMPCPY

#   define MEMPCPY(d, s, n) ((void *) ((char *) memcpy (d, s, n) + (n)))

#  endif

# endif

#endif

#ifndef __P

# if defined __GNUC__ || (defined __STDC__ && __STDC__)

#  define __P(args) args

# else

#  define __P(args) ()

# endif  /* GCC.  */

#endif  /* Not __P.  */

#ifndef PTR

# ifdef __STDC__

#  define PTR void *

# else

#  define PTR char *

# endif

#endif

#ifndef CHAR_BIT

# define CHAR_BIT 8

#endif

#ifndef NULL

# define NULL 0

#endif

/* Test for checking whether a given type is signed or not.

   Some compilers issue a diagnostic about suspicious construct for

   a test that will always fail when comparing a value that can't be

   negative against 0 using `<' or `<=' operator.  */

/* #define TYPE_SIGNED(t) ((t) -1 < 0) */

#define TYPE_SIGNED(t) ((t) -1 < 1)

#ifndef INT_STRLEN_BOUND

/* Bound on length of the string representing an integer value of type t.

   Subtract one for the sign bit if t is signed;

   302 / 1000 is log10 (2) rounded up;

   add one for integer division truncation;

   add one more for a minus sign if t is signed.  */

#define INT_STRLEN_BOUND(t) \

 ((sizeof (t) * CHAR_BIT - TYPE_SIGNED (t)) * 302 / 1000 + 1 + TYPE_SIGNED (t))

#endif

#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 my_strftime_gmtime_r __gmtime_r

# define my_strftime_localtime_r __localtime_r

# define tzname __tzname

# define tzset __tzset

#else

/* If we're a strftime substitute in a GNU program, then prefer gmtime

   to gmtime_r, since many gmtime_r implementations are buggy.

   Similarly for localtime_r.  */

# if ! HAVE_TM_GMTOFF

static struct tm *my_strftime_gmtime_r __P ((const time_t *, struct tm *));

static struct tm *

my_strftime_gmtime_r (t, tp)

     const time_t *t;

     struct tm *tp;

{

  struct tm *l = gmtime (t);

  if (! l)

    return 0;

  *tp = *l;

  return tp;

}

# endif /* ! HAVE_TM_GMTOFF */

static struct tm *my_strftime_localtime_r __P ((const time_t *, struct tm *));

static struct tm *

my_strftime_localtime_r (t, tp)

     const time_t *t;

     struct tm *tp;

{

  struct tm *l = localtime (t);

  if (! l)

    return 0;

  *tp = *l;

  return tp;

}

#endif /* ! defined _LIBC */

#if !defined memset && !defined HAVE_MEMSET && !defined _LIBC

/* Some systems lack the `memset' function and we don't want to

   introduce additional dependencies.  */

/* The SGI compiler reportedly barfs on the trailing null

   if we use a string constant as the initializer.  28 June 1997, rms.  */

static const CHAR_T spaces[16] = /* "                " */

{

  L_(' '),L_(' '),L_(' '),L_(' '),L_(' '),L_(' '),L_(' '),L_(' '),

  L_(' '),L_(' '),L_(' '),L_(' '),L_(' '),L_(' '),L_(' '),L_(' ')

};

static const CHAR_T zeroes[16] = /* "0000000000000000" */

{

  L_('0'),L_('0'),L_('0'),L_('0'),L_('0'),L_('0'),L_('0'),L_('0'),

  L_('0'),L_('0'),L_('0'),L_('0'),L_('0'),L_('0'),L_('0'),L_('0')

};

# define memset_space(P, Len) \

  do {									      \

    int _len = (Len);							      \

									      \

    do									      \

      {									      \

	int _this = _len > 16 ? 16 : _len;				      \

	(P) = MEMPCPY ((P), spaces, _this * sizeof (CHAR_T));		      \

	_len -= _this;							      \

      }									      \

    while (_len > 0);							      \

  } while (0)

# define memset_zero(P, Len) \

  do {									      \

    int _len = (Len);							      \

									      \

    do									      \

      {									      \

	int _this = _len > 16 ? 16 : _len;				      \

	(P) = MEMPCPY ((P), zeroes, _this * sizeof (CHAR_T));		      \

	_len -= _this;							      \

      }									      \

    while (_len > 0);							      \

  } while (0)

#else

# ifdef 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

#endif

#define add(n, f)							      \

  do									      \

    {									      \

      int _n = (n);							      \

      int _delta = width - _n;						      \

      int _incr = _n + (_delta > 0 ? _delta : 0);			      \

      if ((size_t) _incr >= maxsize - i)				      \

	return 0;							      \

      if (p)								      \

	{								      \

	  if (_delta > 0)						      \

	    {								      \

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

		memset_zero (p, _delta);				      \

	      else							      \

		memset_space (p, _delta);				      \

	    }								      \

	  f;								      \

	  p += _n;							      \

	}								      \

      i += _incr;							      \

    } while (0)

#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 ((PTR) p, (const PTR) (s), _n))

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

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

  }

#endif

/* For gawk */

#undef TOLOWER

#undef TOUPPER

#undef ISDIGIT

#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 , loc

# define LOCALE_ARG , loc

# define LOCALE_PARAM_DECL  __locale_t loc;

# define LOCALE_PARAM_PROTO , __locale_t loc

# define HELPER_LOCALE_ARG  , current

#else

# define LOCALE_PARAM

# define LOCALE_PARAM_PROTO

# define LOCALE_ARG

# define LOCALE_PARAM_DECL

# 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 _LIBC

#  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

# else

#  define TOUPPER(Ch, L) (islower (Ch) ? toupper (Ch) : (Ch))

#  define TOLOWER(Ch, L) (isupper (Ch) ? tolower (Ch) : (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)

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

				    size_t len LOCALE_PARAM_PROTO));

static CHAR_T *

memcpy_lowcase (dest, src, len LOCALE_PARAM)

     CHAR_T *dest;

     const CHAR_T *src;

     size_t len;

     LOCALE_PARAM_DECL

{

  while (len-- > 0)

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

  return dest;

}

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

				    size_t len LOCALE_PARAM_PROTO));

static CHAR_T *

memcpy_uppcase (dest, src, len LOCALE_PARAM)

     CHAR_T *dest;

     const CHAR_T *src;

     size_t len;

     LOCALE_PARAM_DECL

{

  while (len-- > 0)

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

  return dest;

}

#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 __P ((const struct tm *, const struct tm *));

static int

tm_diff (a, b)

     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 = (a->tm_year >> 2) + (TM_YEAR_BASE >> 2) - ! (a->tm_year & 3);

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

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

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

  int a400 = a100 >> 2;

  int b400 = 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 __P ((int, int));

#ifdef __GNUC__

__inline__

#endif

static int

iso_week_days (yday, wday)

     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);

}

#if !(defined _NL_CURRENT || HAVE_STRFTIME)

static CHAR_T const weekday_name[][10] =

  {

    L_("Sunday"), L_("Monday"), L_("Tuesday"), L_("Wednesday"),

    L_("Thursday"), L_("Friday"), L_("Saturday")

  };

static CHAR_T const month_name[][10] =

  {

    L_("January"), L_("February"), L_("March"), L_("April"), L_("May"),

    L_("June"), L_("July"), L_("August"), L_("September"), L_("October"),

    L_("November"), L_("December")

  };

#endif

#ifdef emacs

# define my_strftime emacs_strftimeu

# define ut_argument , ut

# define ut_argument_spec int ut;

# define ut_argument_spec_iso , int ut

#else

# ifdef 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 ut_argument

# define ut_argument_spec

# define ut_argument_spec_iso

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

# define ut 0

#endif

#if !defined _LIBC && HAVE_TZNAME && HAVE_TZSET

  /* Solaris 2.5 tzset sometimes modifies the storage returned by localtime.

     Work around this bug by copying *tp before it might be munged.  */

  size_t _strftime_copytm __P ((char *, size_t, const char *,

			        const struct tm * ut_argument_spec_iso));

  size_t

  my_strftime (s, maxsize, format, tp ut_argument)

      CHAR_T *s;

      size_t maxsize;

      const CHAR_T *format;

      const struct tm *tp;

      ut_argument_spec

  {

    struct tm tmcopy;

    tmcopy = *tp;

    return _strftime_copytm (s, maxsize, format, &tmcopy ut_argument);

  }

# undef my_strftime

# define my_strftime _strftime_copytm

#endif

/* 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) UINT_MAX for MAXSIZE.  */

size_t

my_strftime (s, maxsize, format, tp ut_argument LOCALE_PARAM)

      CHAR_T *s;

      size_t maxsize;

      const CHAR_T *format;

      const struct tm *tp;

      ut_argument_spec

      LOCALE_PARAM_DECL

{

#if defined _LIBC && defined USE_IN_EXTENDED_LOCALE_MODEL

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

#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 *) _NL_CURRENT (LC_TIME, NLW(ABDAY_1) + tp->tm_wday))

# define f_wkday \

  ((const CHAR_T *) _NL_CURRENT (LC_TIME, NLW(DAY_1) + tp->tm_wday))

# define a_month \

  ((const CHAR_T *) _NL_CURRENT (LC_TIME, NLW(ABMON_1) + tp->tm_mon))

# define f_month \

  ((const CHAR_T *) _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)

#else

# if !HAVE_STRFTIME

#  define f_wkday (weekday_name[tp->tm_wday])

#  define f_month (month_name[tp->tm_mon])

#  define a_wkday f_wkday

#  define a_month f_month

#  define ampm (L_("AMPM") + 2 * (tp->tm_hour > 11))

  size_t aw_len = 3;

  size_t am_len = 3;

  size_t ap_len = 2;

# endif

#endif

  const char *zone;

  size_t i = 0;

  CHAR_T *p = s;

  const CHAR_T *f;

#if DO_MULTIBYTE && !defined COMPILE_WIDE

  const char *format_end = NULL;

#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 (ut)

    {

      if (! (zone && *zone))

	zone = "GMT";

    }

  else

    {

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

	 though strftime called tzset.  */

# if HAVE_TZSET

      tzset ();

# endif

    }

#endif

  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;		/* Max digits for numeric format.  */

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

      int negative_number;	/* 1 if the number is negative.  */

      const CHAR_T *subfmt;

      CHAR_T *bufp;

      CHAR_T buf[1 + (sizeof (int) < sizeof (time_t)

		      ? INT_STRLEN_BOUND (time_t)

		      : INT_STRLEN_BOUND (int))];

      int width = -1;

      int to_lowcase = 0;

      int to_uppcase = 0;

      int change_case = 0;

      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.  */

	  add (1, *p = *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_('%'))

	{

	  add (1, *p = *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 = 1;

	      continue;

	    case L_('#'):

	      change_case = 1;

	      continue;

	    default:

	      break;

	    }

	  break;

	}

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

      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) \

	  digits = d > width ? d : width;				      \

	  number_value = v; goto do_number

#define DO_NUMBER_SPACEPAD(d, v) \

	  digits = d > width ? d : width;				      \

	  number_value = v; goto do_number_spacepad

	case L_('%'):

	  if (modifier != 0)

	    goto bad_format;

	  add (1, *p = *f);

	  break;

	case L_('a'):

	  if (modifier != 0)

	    goto bad_format;

	  if (change_case)

	    {

	      to_uppcase = 1;

	      to_lowcase = 0;

	    }

#if defined _NL_CURRENT || !HAVE_STRFTIME

	  cpy (aw_len, a_wkday);

	  break;

#else

	  goto underlying_strftime;

#endif

	case 'A':

	  if (modifier != 0)

	    goto bad_format;

	  if (change_case)

	    {

	      to_uppcase = 1;

	      to_lowcase = 0;

	    }

#if defined _NL_CURRENT || !HAVE_STRFTIME

	  cpy (STRLEN (f_wkday), f_wkday);

	  break;

#else

	  goto underlying_strftime;

#endif

	case L_('b'):

	case L_('h'):

	  if (change_case)

	    {

	      to_uppcase = 1;

	      to_lowcase = 0;

	    }

	  if (modifier != 0)

	    goto bad_format;

#if defined _NL_CURRENT || !HAVE_STRFTIME

	  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 = 1;

	      to_lowcase = 0;

	    }

#if defined _NL_CURRENT || !HAVE_STRFTIME

	  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

# if HAVE_STRFTIME

	  goto underlying_strftime;

# else

	  subfmt = L_("%a %b %e %H:%M:%S %Y");

# endif

#endif

	subformat:

	  {