/* Copyright (C) 2002-2018 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, see

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

#ifdef HAVE_CONFIG_H

# include <config.h>

#endif

#include <assert.h>

#include <ctype.h>

#include <langinfo.h>

#include <limits.h>

#include <string.h>

#include <time.h>

#include <stdbool.h>

#ifdef _LIBC

# define HAVE_LOCALTIME_R 0

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

#endif

#if ! HAVE_LOCALTIME_R && ! defined localtime_r

# ifdef _LIBC

#  define localtime_r __localtime_r

# else

/* Approximate localtime_r as best we can in its absence.  */

#  define localtime_r my_localtime_r

static struct tm *localtime_r (const time_t *, struct tm *);

static struct tm *

localtime_r (const time_t *t, struct tm *tp)

{

  struct tm *l = localtime (t);

  if (! l)

    return 0;

  *tp = *l;

  return tp;

}

# endif /* ! _LIBC */

#endif /* ! HAVE_LOCALTIME_R && ! defined (localtime_r) */

#define match_char(ch1, ch2) if (ch1 != ch2) return NULL

#if defined __GNUC__ && __GNUC__ >= 2

# define match_string(cs1, s2) \

  ({ size_t len = strlen (cs1);						      \

     int result = __strncasecmp_l ((cs1), (s2), len, locale) == 0;	      \

     if (result) (s2) += len;						      \

     result; })

#else

/* Oh come on.  Get a reasonable compiler.  */

# define match_string(cs1, s2) \

  (strncasecmp ((cs1), (s2), strlen (cs1)) ? 0 : ((s2) += strlen (cs1), 1))

#endif

/* We intentionally do not use isdigit() for testing because this will

   lead to problems with the wide character version.  */

#define get_number(from, to, n) \

  do {									      \

    int __n = n;							      \

    val = 0;								      \

    while (ISSPACE (*rp))						      \

      ++rp;								      \

    if (*rp < '0' || *rp > '9')						      \

      return NULL;							      \

    do {								      \

      val *= 10;							      \

      val += *rp++ - '0';						      \

    } while (--__n > 0 && val * 10 <= to && *rp >= '0' && *rp <= '9');	      \

    if (val < from || val > to)						      \

      return NULL;							      \

  } while (0)

#ifdef _NL_CURRENT

# define get_alt_number(from, to, n) \

  ({									      \

     __label__ do_normal;						      \

									      \

     if (s.decided != raw)						      \

       {								      \

	 val = _nl_parse_alt_digit (&rp HELPER_LOCALE_ARG);		      \

	 if (val == -1 && s.decided != loc)				      \

	   {								      \

	     s.decided = loc;						      \

	     goto do_normal;						      \

	   }								      \

	if (val < from || val > to)					      \

	  return NULL;							      \

       }								      \

     else								      \

       {								      \

       do_normal:							      \

	 get_number (from, to, n);					      \

       }								      \

    0;									      \

  })

#else

# define get_alt_number(from, to, n) \

  /* We don't have the alternate representation.  */			      \

  get_number(from, to, n)

#endif

#define recursive(new_fmt) \

  (*(new_fmt) != '\0'							      \

   && (rp = __strptime_internal (rp, (new_fmt), tm, &s LOCALE_ARG)) != NULL)

#ifdef _LIBC

/* This is defined in locale/C-time.c in the GNU libc.  */

extern const struct __locale_data _nl_C_LC_TIME attribute_hidden;

# define weekday_name (&_nl_C_LC_TIME.values[_NL_ITEM_INDEX (DAY_1)].string)

# define ab_weekday_name \

  (&_nl_C_LC_TIME.values[_NL_ITEM_INDEX (ABDAY_1)].string)

# define month_name (&_nl_C_LC_TIME.values[_NL_ITEM_INDEX (MON_1)].string)

# define ab_month_name (&_nl_C_LC_TIME.values[_NL_ITEM_INDEX (ABMON_1)].string)

# define alt_month_name \

  (&_nl_C_LC_TIME.values[_NL_ITEM_INDEX (ALTMON_1)].string)

# define ab_alt_month_name \

  (&_nl_C_LC_TIME.values[_NL_ITEM_INDEX (_NL_ABALTMON_1)].string)

# define HERE_D_T_FMT (_nl_C_LC_TIME.values[_NL_ITEM_INDEX (D_T_FMT)].string)

# define HERE_D_FMT (_nl_C_LC_TIME.values[_NL_ITEM_INDEX (D_FMT)].string)

# define HERE_AM_STR (_nl_C_LC_TIME.values[_NL_ITEM_INDEX (AM_STR)].string)

# define HERE_PM_STR (_nl_C_LC_TIME.values[_NL_ITEM_INDEX (PM_STR)].string)

# define HERE_T_FMT_AMPM \

  (_nl_C_LC_TIME.values[_NL_ITEM_INDEX (T_FMT_AMPM)].string)

# define HERE_T_FMT (_nl_C_LC_TIME.values[_NL_ITEM_INDEX (T_FMT)].string)

# define strncasecmp(s1, s2, n) __strncasecmp (s1, s2, n)

#else

static char const weekday_name[][10] =

  {

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

    "Thursday", "Friday", "Saturday"

  };

static char const ab_weekday_name[][4] =

  {

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

  };

static char const month_name[][10] =

  {

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

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

  };

static char const ab_month_name[][4] =

  {

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

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

  };

# define HERE_D_T_FMT "%a %b %e %H:%M:%S %Y"

# define HERE_D_FMT "%m/%d/%y"

# define HERE_AM_STR "AM"

# define HERE_PM_STR "PM"

# define HERE_T_FMT_AMPM "%I:%M:%S %p"

# define HERE_T_FMT "%H:%M:%S"

static const unsigned short int __mon_yday[2][13] =

  {

    /* Normal years.  */

    { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365 },

    /* Leap years.  */

    { 0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335, 366 }

  };

#endif

#if defined _LIBC

/* 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 strptime		__strptime_l

# undef _NL_CURRENT

# define _NL_CURRENT(category, item) \

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

# undef _NL_CURRENT_WORD

# define _NL_CURRENT_WORD(category, item) \

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

# define LOCALE_PARAM , locale_t locale

# define LOCALE_ARG , locale

# define HELPER_LOCALE_ARG , current

# define ISSPACE(Ch) __isspace_l (Ch, locale)

#else

# define LOCALE_PARAM

# define LOCALE_ARG

# define HELPER_LOCALE_ARG

# define ISSPACE(Ch) isspace (Ch)

#endif

#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

/* Compute the day of the week.  */

static void

day_of_the_week (struct tm *tm)

{

  /* We know that January 1st 1970 was a Thursday (= 4).  Compute the

     difference between this data in the one on TM and so determine

     the weekday.  */

  int corr_year = 1900 + tm->tm_year - (tm->tm_mon < 2);

  int wday = (-473

	      + (365 * (tm->tm_year - 70))

	      + (corr_year / 4)

	      - ((corr_year / 4) / 25) + ((corr_year / 4) % 25 < 0)

	      + (((corr_year / 4) / 25) / 4)

	      + __mon_yday[0][tm->tm_mon]

	      + tm->tm_mday - 1);

  tm->tm_wday = ((wday % 7) + 7) % 7;

}

/* Compute the day of the year.  */

static void

day_of_the_year (struct tm *tm)

{

  tm->tm_yday = (__mon_yday[__isleap (1900 + tm->tm_year)][tm->tm_mon]

		 + (tm->tm_mday - 1));

}

#ifdef _LIBC

char *

#else

static char *

#endif

__strptime_internal (const char *rp, const char *fmt, struct tm *tmp,

		     void *statep LOCALE_PARAM)

{

#ifdef _LIBC

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

#endif

  const char *rp_backup;

  const char *rp_longest;

  int cnt;

  int cnt_longest;

  size_t val;

  size_t num_eras;

  struct era_entry *era = NULL;

  enum ptime_locale_status { not, loc, raw } decided_longest;

  struct __strptime_state

  {

    unsigned int have_I : 1;

    unsigned int have_wday : 1;

    unsigned int have_yday : 1;

    unsigned int have_mon : 1;

    unsigned int have_mday : 1;

    unsigned int have_uweek : 1;

    unsigned int have_wweek : 1;

    unsigned int is_pm : 1;

    unsigned int want_century : 1;

    unsigned int want_era : 1;

    unsigned int want_xday : 1;

    enum ptime_locale_status decided : 2;

    signed char week_no;

    signed char century;

    int era_cnt;

  } s;

  struct tm tmb;

  struct tm *tm;

  if (statep == NULL)

    {

      memset (&s, 0, sizeof (s));

      s.century = -1;

      s.era_cnt = -1;

#ifdef _NL_CURRENT

      s.decided = not;

#else

      s.decided = raw;

#endif

      tm = tmp;

    }

  else

    {

      s = *(struct __strptime_state *) statep;

      tmb = *tmp;

      tm = &tm;;

    }

  while (*fmt != '\0')

    {

      /* A white space in the format string matches 0 more or white

	 space in the input string.  */

      if (ISSPACE (*fmt))

	{

	  while (ISSPACE (*rp))

	    ++rp;

	  ++fmt;

	  continue;

	}

      /* Any character but `%' must be matched by the same character

	 in the iput string.  */

      if (*fmt != '%')

	{

	  match_char (*fmt++, *rp++);

	  continue;

	}

      ++fmt;

      /* We discard strftime modifiers.  */

      while (*fmt == '-' || *fmt == '_' || *fmt == '0'

	     || *fmt == '^' || *fmt == '#')

	++fmt;

      /* And field width.  */

      while (*fmt >= '0' && *fmt <= '9')

	++fmt;

      /* In some cases, modifiers are handled by adjusting state and

         then restarting the switch statement below.  */

    start_over:

      /* Make back up of current processing pointer.  */

      rp_backup = rp;

      switch (*fmt++)

	{

	case '%':

	  /* Match the `%' character itself.  */

	  match_char ('%', *rp++);

	  break;

	case 'a':

	case 'A':

	  /* Match day of week.  */

	  rp_longest = NULL;

	  decided_longest = s.decided;

	  cnt_longest = -1;

	  for (cnt = 0; cnt < 7; ++cnt)

	    {

	      const char *trp;

#ifdef _NL_CURRENT

	      if (s.decided !=raw)

		{

		  trp = rp;

		  if (match_string (_NL_CURRENT (LC_TIME, DAY_1 + cnt), trp)

		      && trp > rp_longest)

		    {

		      rp_longest = trp;

		      cnt_longest = cnt;

		      if (s.decided == not

			  && strcmp (_NL_CURRENT (LC_TIME, DAY_1 + cnt),

				     weekday_name[cnt]))

			decided_longest = loc;

		    }

		  trp = rp;

		  if (match_string (_NL_CURRENT (LC_TIME, ABDAY_1 + cnt), trp)

		      && trp > rp_longest)

		    {

		      rp_longest = trp;

		      cnt_longest = cnt;

		      if (s.decided == not

			  && strcmp (_NL_CURRENT (LC_TIME, ABDAY_1 + cnt),

				     ab_weekday_name[cnt]))

			decided_longest = loc;

		    }

		}

#endif

	      if (s.decided != loc

		  && (((trp = rp, match_string (weekday_name[cnt], trp))

		       && trp > rp_longest)

		      || ((trp = rp, match_string (ab_weekday_name[cnt], rp))

			  && trp > rp_longest)))

		{

		  rp_longest = trp;

		  cnt_longest = cnt;

		  decided_longest = raw;

		}

	    }

	  if (rp_longest == NULL)

	    /* Does not match a weekday name.  */

	    return NULL;

	  rp = rp_longest;

	  s.decided = decided_longest;

	  tm->tm_wday = cnt_longest;

	  s.have_wday = 1;

	  break;

	case 'b':

	case 'B':

	case 'h':

	  /* Match month name.  */

	  rp_longest = NULL;

	  decided_longest = s.decided;

	  cnt_longest = -1;

	  for (cnt = 0; cnt < 12; ++cnt)

	    {

	      const char *trp;

#ifdef _NL_CURRENT

	      if (s.decided !=raw)

		{

		  trp = rp;

		  if (match_string (_NL_CURRENT (LC_TIME, MON_1 + cnt), trp)

		      && trp > rp_longest)

		    {

		      rp_longest = trp;

		      cnt_longest = cnt;

		      if (s.decided == not

			  && strcmp (_NL_CURRENT (LC_TIME, MON_1 + cnt),

				     month_name[cnt]))

			decided_longest = loc;

		    }

		  trp = rp;

		  if (match_string (_NL_CURRENT (LC_TIME, ABMON_1 + cnt), trp)

		      && trp > rp_longest)

		    {

		      rp_longest = trp;

		      cnt_longest = cnt;

		      if (s.decided == not

			  && strcmp (_NL_CURRENT (LC_TIME, ABMON_1 + cnt),

				     ab_month_name[cnt]))

			decided_longest = loc;

		    }

#ifdef _LIBC

		  /* Now check the alt month.  */

		  trp = rp;

		  if (match_string (_NL_CURRENT (LC_TIME, ALTMON_1 + cnt), trp)

		      && trp > rp_longest)

		    {

		      rp_longest = trp;

		      cnt_longest = cnt;

		      if (s.decided == not

			  && strcmp (_NL_CURRENT (LC_TIME, ALTMON_1 + cnt),

				     alt_month_name[cnt]))

			decided_longest = loc;

		    }

		  trp = rp;

		  if (match_string (_NL_CURRENT (LC_TIME, _NL_ABALTMON_1 + cnt),

				    trp)

		      && trp > rp_longest)

		    {

		      rp_longest = trp;

		      cnt_longest = cnt;

		      if (s.decided == not

			  && strcmp (_NL_CURRENT (LC_TIME, _NL_ABALTMON_1 + cnt),

				     alt_month_name[cnt]))

			decided_longest = loc;

		    }

#endif

		}

#endif

	      if (s.decided != loc

		  && (((trp = rp, match_string (month_name[cnt], trp))

		       && trp > rp_longest)

		      || ((trp = rp, match_string (ab_month_name[cnt], trp))

			  && trp > rp_longest)

#ifdef _LIBC

		      || ((trp = rp, match_string (alt_month_name[cnt], trp))

			  && trp > rp_longest)

		      || ((trp = rp, match_string (ab_alt_month_name[cnt], trp))

			  && trp > rp_longest)

#endif

	      ))

		{

		  rp_longest = trp;

		  cnt_longest = cnt;

		  decided_longest = raw;

		}

	    }

	  if (rp_longest == NULL)

	    /* Does not match a month name.  */

	    return NULL;

	  rp = rp_longest;

	  s.decided = decided_longest;

	  tm->tm_mon = cnt_longest;

	  s.have_mon = 1;

	  s.want_xday = 1;

	  break;

	case 'c':

	  /* Match locale's date and time format.  */

#ifdef _NL_CURRENT

	  if (s.decided != raw)

	    {

	      if (!recursive (_NL_CURRENT (LC_TIME, D_T_FMT)))

		{

		  if (s.decided == loc)

		    return NULL;

		  else

		    rp = rp_backup;

		}

	      else

		{

		  if (s.decided == not &&

		      strcmp (_NL_CURRENT (LC_TIME, D_T_FMT), HERE_D_T_FMT))

		    s.decided = loc;

		  s.want_xday = 1;

		  break;

		}

	      s.decided = raw;

	    }

#endif

	  if (!recursive (HERE_D_T_FMT))

	    return NULL;

	  s.want_xday = 1;

	  break;

	case 'C':

	  /* Match century number.  */

	match_century:

	  get_number (0, 99, 2);

	  s.century = val;

	  s.want_xday = 1;

	  break;

	case 'd':

	case 'e':

	  /* Match day of month.  */

	  get_number (1, 31, 2);

	  tm->tm_mday = val;

	  s.have_mday = 1;

	  s.want_xday = 1;

	  break;

	case 'F':

	  if (!recursive ("%Y-%m-%d"))

	    return NULL;

	  s.want_xday = 1;

	  break;

	case 'x':

#ifdef _NL_CURRENT

	  if (s.decided != raw)

	    {

	      if (!recursive (_NL_CURRENT (LC_TIME, D_FMT)))

		{

		  if (s.decided == loc)

		    return NULL;

		  else

		    rp = rp_backup;

		}

	      else

		{

		  if (s.decided == not

		      && strcmp (_NL_CURRENT (LC_TIME, D_FMT), HERE_D_FMT))

		    s.decided = loc;

		  s.want_xday = 1;

		  break;

		}

	      s.decided = raw;

	    }

#endif

	  /* Fall through.  */

	case 'D':

	  /* Match standard day format.  */

	  if (!recursive (HERE_D_FMT))

	    return NULL;

	  s.want_xday = 1;

	  break;

	case 'k':

	case 'H':

	  /* Match hour in 24-hour clock.  */

	  get_number (0, 23, 2);

	  tm->tm_hour = val;

	  s.have_I = 0;

	  break;

	case 'l':

	  /* Match hour in 12-hour clock.  GNU extension.  */

	case 'I':

	  /* Match hour in 12-hour clock.  */

	  get_number (1, 12, 2);

	  tm->tm_hour = val % 12;

	  s.have_I = 1;

	  break;

	case 'j':

	  /* Match day number of year.  */

	  get_number (1, 366, 3);

	  tm->tm_yday = val - 1;

	  s.have_yday = 1;

	  break;

	case 'm':

	  /* Match number of month.  */

	  get_number (1, 12, 2);

	  tm->tm_mon = val - 1;

	  s.have_mon = 1;

	  s.want_xday = 1;

	  break;

	case 'M':

	  /* Match minute.  */

	  get_number (0, 59, 2);

	  tm->tm_min = val;

	  break;

	case 'n':

	case 't':

	  /* Match any white space.  */

	  while (ISSPACE (*rp))

	    ++rp;

	  break;

	case 'p':

	  /* Match locale's equivalent of AM/PM.  */

#ifdef _NL_CURRENT

	  if (s.decided != raw)

	    {

	      if (match_string (_NL_CURRENT (LC_TIME, AM_STR), rp))

		{

		  if (strcmp (_NL_CURRENT (LC_TIME, AM_STR), HERE_AM_STR))

		    s.decided = loc;

		  s.is_pm = 0;

		  break;

		}

	      if (match_string (_NL_CURRENT (LC_TIME, PM_STR), rp))

		{

		  if (strcmp (_NL_CURRENT (LC_TIME, PM_STR), HERE_PM_STR))

		    s.decided = loc;

		  s.is_pm = 1;

		  break;

		}

	      s.decided = raw;

	    }

#endif

	  if (!match_string (HERE_AM_STR, rp))

	    {

	      if (match_string (HERE_PM_STR, rp))

		s.is_pm = 1;

	      else

		return NULL;

	    }

	  else

	    s.is_pm = 0;

	  break;

	case 'r':

#ifdef _NL_CURRENT

	  if (s.decided != raw)

	    {

	      if (!recursive (_NL_CURRENT (LC_TIME, T_FMT_AMPM)))

		{

		  if (s.decided == loc)

		    return NULL;

		  else

		    rp = rp_backup;

		}

	      else

		{

		  if (s.decided == not &&

		      strcmp (_NL_CURRENT (LC_TIME, T_FMT_AMPM),

			      HERE_T_FMT_AMPM))

		    s.decided = loc;

		  break;

		}

	      s.decided = raw;

	    }

#endif

	  if (!recursive (HERE_T_FMT_AMPM))

	    return NULL;

	  break;

	case 'R':

	  if (!recursive ("%H:%M"))

	    return NULL;

	  break;

	case 's':

	  {

	    /* The number of seconds may be very high so we cannot use

	       the `get_number' macro.  Instead read the number

	       character for character and construct the result while

	       doing this.  */

	    time_t secs = 0;

	    if (*rp < '0' || *rp > '9')

	      /* We need at least one digit.  */

	      return NULL;

	    do

	      {

		secs *= 10;

		secs += *rp++ - '0';

	      }

	    while (*rp >= '0' && *rp <= '9');

	    if (localtime_r (&secs, tm) == NULL)

	      /* Error in function.  */

	      return NULL;

	  }

	  break;

	case 'S':

	  get_number (0, 61, 2);

	  tm->tm_sec = val;

	  break;

	case 'X':

#ifdef _NL_CURRENT

	  if (s.decided != raw)

	    {

	      if (!recursive (_NL_CURRENT (LC_TIME, T_FMT)))

		{

		  if (s.decided == loc)

		    return NULL;

		  else

		    rp = rp_backup;

		}

	      else

		{

		  if (strcmp (_NL_CURRENT (LC_TIME, T_FMT), HERE_T_FMT))

		    s.decided = loc;

		  break;

		}

	      s.decided = raw;

	    }

#endif

	  /* Fall through.  */

	case 'T':

	  if (!recursive (HERE_T_FMT))

	    return NULL;

	  break;

	case 'u':

	  get_number (1, 7, 1);

	  tm->tm_wday = val % 7;

	  s.have_wday = 1;

	  break;

	case 'g':

	  get_number (0, 99, 2);

	  /* XXX This cannot determine any field in TM.  */

	  break;

	case 'G':

	  if (*rp < '0' || *rp > '9')

	    return NULL;

	  /* XXX Ignore the number since we would need some more

	     information to compute a real date.  */

	  do

	    ++rp;

	  while (*rp >= '0' && *rp <= '9');

	  break;

	case 'U':

	  get_number (0, 53, 2);

	  s.week_no = val;

	  s.have_uweek = 1;

	  break;

	case 'W':

	  get_number (0, 53, 2);

	  s.week_no = val;

	  s.have_wweek = 1;

	  break;

	case 'V':

	  get_number (0, 53, 2);

	  /* XXX This cannot determine any field in TM without some

	     information.  */

	  break;

	case 'w':

	  /* Match number of weekday.  */

	  get_number (0, 6, 1);

	  tm->tm_wday = val;

	  s.have_wday = 1;

	  break;

	case 'y':

	match_year_in_century:

	  /* Match year within century.  */

	  get_number (0, 99, 2);

	  /* The "Year 2000: The Millennium Rollover" paper suggests that

	     values in the range 69-99 refer to the twentieth century.  */

	  tm->tm_year = val >= 69 ? val : val + 100;

	  /* Indicate that we want to use the century, if specified.  */

	  s.want_century = 1;

	  s.want_xday = 1;

	  break;

	case 'Y':

	  /* Match year including century number.  */

	  get_number (0, 9999, 4);

	  tm->tm_year = val - 1900;

	  s.want_century = 0;

	  s.want_xday = 1;

	  break;

	case 'Z':

	  /* Read timezone but perform no conversion.  */

	  while (ISSPACE (*rp))

	    rp++;

	  while (!ISSPACE (*rp) && *rp != '\0')

	    rp++;

	  break;

	case 'z':

	  /* We recognize four formats:

	     1. Two digits specify hours.

	     2. Four digits specify hours and minutes.

	     3. Two digits, ':', and two digits specify hours and minutes.

	     4. 'Z' is equivalent to +0000.  */

	  {

	    val = 0;

	    while (ISSPACE (*rp))

	      ++rp;

	    if (*rp == 'Z')

	      {

		++rp;

		tm->tm_gmtoff = 0;

		break;

	      }

	    if (*rp != '+' && *rp != '-')

	      return NULL;

	    bool neg = *rp++ == '-';

	    int n = 0;

	    while (n < 4 && *rp >= '0' && *rp <= '9')

	      {

		val = val * 10 + *rp++ - '0';

		++n;

		if (*rp == ':' && n == 2 && isdigit (*(rp + 1)))

		  ++rp;

	      }

	    if (n == 2)

	      val *= 100;

	    else if (n != 4)

	      /* Only two or four digits recognized.  */

	      return NULL;

	    else if (val % 100 >= 60)

	      /* Minutes valid range is 0 through 59.  */

	      return NULL;

	    tm->tm_gmtoff = (val / 100) * 3600 + (val % 100) * 60;

	    if (neg)

	      tm->tm_gmtoff = -tm->tm_gmtoff;

	  }

	  break;

	case 'E':

#ifdef _NL_CURRENT

	  switch (*fmt++)

	    {

	    case 'c':

	      /* Match locale's alternate date and time format.  */

	      if (s.decided != raw)

		{

		  const char *fmt = _NL_CURRENT (LC_TIME, ERA_D_T_FMT);

		  if (*fmt == '\0')

		    fmt = _NL_CURRENT (LC_TIME, D_T_FMT);

		  if (!recursive (fmt))

		    {

		      if (s.decided == loc)

			return NULL;

		      else

			rp = rp_backup;

		    }

		  else

		    {

		      if (strcmp (fmt, HERE_D_T_FMT))

			s.decided = loc;

		      s.want_xday = 1;

		      break;

		    }

		  s.decided = raw;

		}

	      /* The C locale has no era information, so use the

		 normal representation.  */

	      if (!recursive (HERE_D_T_FMT))

		return NULL;

	      s.want_xday = 1;

	      break;

	    case 'C':

	      if (s.decided != raw)

		{

		  if (s.era_cnt >= 0)

		    {

		      era = _nl_select_era_entry (s.era_cnt HELPER_LOCALE_ARG);

		      if (era != NULL && match_string (era->era_name, rp))

			{

			  s.decided = loc;

			  break;

			}

		      else

			return NULL;

		    }

		  num_eras = _NL_CURRENT_WORD (LC_TIME,

					       _NL_TIME_ERA_NUM_ENTRIES);

		  for (s.era_cnt = 0; s.era_cnt < (int) num_eras;

		       ++s.era_cnt, rp = rp_backup)

		    {

		      era = _nl_select_era_entry (s.era_cnt

						  HELPER_LOCALE_ARG);

		      if (era != NULL && match_string (era->era_name, rp))

			{

			  s.decided = loc;

			  break;

			}

		    }

		  if (s.era_cnt != (int) num_eras)

		    break;