time/strptime_l.c

   1 /* Copyright (C) 2002-2017 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, see
  16    <http://www.gnu.org/licenses/>.  */
  17
  18 #ifdef HAVE_CONFIG_H
  19 # include <config.h>
  20 #endif
  21
  22 #include <assert.h>
  23 #include <ctype.h>
  24 #include <langinfo.h>
  25 #include <limits.h>
  26 #include <string.h>
  27 #include <time.h>
  28 #include <stdbool.h>
  29
  30 #ifdef _LIBC
  31 # define HAVE_LOCALTIME_R 0
  32 # include "../locale/localeinfo.h"
  33 #endif
  34
  35
  36 #if ! HAVE_LOCALTIME_R && ! defined localtime_r
  37 # ifdef _LIBC
  38 #  define localtime_r __localtime_r
  39 # else
  40 /* Approximate localtime_r as best we can in its absence.  */
  41 #  define localtime_r my_localtime_r
  42 static struct tm *localtime_r (const time_t *, struct tm *);
  43 static struct tm *
  44 localtime_r (const time_t *t, struct tm *tp)
  45 {
  46   struct tm *l = localtime (t);
  47   if (! l)
  48     return 0;
  49   *tp = *l;
  50   return tp;
  51 }
  52 # endif /* ! _LIBC */
  53 #endif /* ! HAVE_LOCALTIME_R && ! defined (localtime_r) */
  54
  55
  56 #define match_char(ch1, ch2) if (ch1 != ch2) return NULL
  57 #if defined __GNUC__ && __GNUC__ >= 2
  58 # define match_string(cs1, s2) \
  59   ({ size_t len = strlen (cs1);                                               \
  60      int result = __strncasecmp_l ((cs1), (s2), len, locale) == 0;            \
  61      if (result) (s2) += len;                                                 \
  62      result; })
  63 #else
  64 /* Oh come on.  Get a reasonable compiler.  */
  65 # define match_string(cs1, s2) \
  66   (strncasecmp ((cs1), (s2), strlen (cs1)) ? 0 : ((s2) += strlen (cs1), 1))
  67 #endif
  68 /* We intentionally do not use isdigit() for testing because this will
  69    lead to problems with the wide character version.  */
  70 #define get_number(from, to, n) \
  71   do {                                                                        \
  72     int __n = n;                                                              \
  73     val = 0;                                                                  \
  74     while (ISSPACE (*rp))                                                     \
  75       ++rp;                                                                   \
  76     if (*rp < '0' || *rp > '9')                                               \
  77       return NULL;                                                            \
  78     do {                                                                      \
  79       val *= 10;                                                              \
  80       val += *rp++ - '0';                                                     \
  81     } while (--__n > 0 && val * 10 <= to && *rp >= '0' && *rp <= '9');        \
  82     if (val < from || val > to)                                               \
  83       return NULL;                                                            \
  84   } while (0)
  85 #ifdef _NL_CURRENT
  86 # define get_alt_number(from, to, n) \
  87   ({                                                                          \
  88      __label__ do_normal;                                                     \
  89                                                                               \
  90      if (s.decided != raw)                                                    \
  91        {                                                                      \
  92          val = _nl_parse_alt_digit (&rp HELPER_LOCALE_ARG);                   \
  93          if (val == -1 && s.decided != loc)                                   \
  94            {                                                                  \
  95              s.decided = loc;                                                 \
  96              goto do_normal;                                                  \
  97            }                                                                  \
  98         if (val < from || val > to)                                           \
  99           return NULL;                                                        \
 100        }                                                                      \
 101      else                                                                     \
 102        {                                                                      \
 103        do_normal:                                                             \
 104          get_number (from, to, n);                                            \
 105        }                                                                      \
 106     0;                                                                        \
 107   })
 108 #else
 109 # define get_alt_number(from, to, n) \
 110   /* We don't have the alternate representation.  */                          \
 111   get_number(from, to, n)
 112 #endif
 113 #define recursive(new_fmt) \
 114   (*(new_fmt) != '\0'                                                         \
 115    && (rp = __strptime_internal (rp, (new_fmt), tm, &s LOCALE_ARG)) != NULL)
 116
 117
 118 #ifdef _LIBC
 119 /* This is defined in locale/C-time.c in the GNU libc.  */
 120 extern const struct __locale_data _nl_C_LC_TIME attribute_hidden;
 121
 122 # define weekday_name (&_nl_C_LC_TIME.values[_NL_ITEM_INDEX (DAY_1)].string)
 123 # define ab_weekday_name \
 124   (&_nl_C_LC_TIME.values[_NL_ITEM_INDEX (ABDAY_1)].string)
 125 # define month_name (&_nl_C_LC_TIME.values[_NL_ITEM_INDEX (MON_1)].string)
 126 # define ab_month_name (&_nl_C_LC_TIME.values[_NL_ITEM_INDEX (ABMON_1)].string)
 127 # define HERE_D_T_FMT (_nl_C_LC_TIME.values[_NL_ITEM_INDEX (D_T_FMT)].string)
 128 # define HERE_D_FMT (_nl_C_LC_TIME.values[_NL_ITEM_INDEX (D_FMT)].string)
 129 # define HERE_AM_STR (_nl_C_LC_TIME.values[_NL_ITEM_INDEX (AM_STR)].string)
 130 # define HERE_PM_STR (_nl_C_LC_TIME.values[_NL_ITEM_INDEX (PM_STR)].string)
 131 # define HERE_T_FMT_AMPM \
 132   (_nl_C_LC_TIME.values[_NL_ITEM_INDEX (T_FMT_AMPM)].string)
 133 # define HERE_T_FMT (_nl_C_LC_TIME.values[_NL_ITEM_INDEX (T_FMT)].string)
 134
 135 # define strncasecmp(s1, s2, n) __strncasecmp (s1, s2, n)
 136 #else
 137 static char const weekday_name[][10] =
 138   {
 139     "Sunday", "Monday", "Tuesday", "Wednesday",
 140     "Thursday", "Friday", "Saturday"
 141   };
 142 static char const ab_weekday_name[][4] =
 143   {
 144     "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"
 145   };
 146 static char const month_name[][10] =
 147   {
 148     "January", "February", "March", "April", "May", "June",
 149     "July", "August", "September", "October", "November", "December"
 150   };
 151 static char const ab_month_name[][4] =
 152   {
 153     "Jan", "Feb", "Mar", "Apr", "May", "Jun",
 154     "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
 155   };
 156 # define HERE_D_T_FMT "%a %b %e %H:%M:%S %Y"
 157 # define HERE_D_FMT "%m/%d/%y"
 158 # define HERE_AM_STR "AM"
 159 # define HERE_PM_STR "PM"
 160 # define HERE_T_FMT_AMPM "%I:%M:%S %p"
 161 # define HERE_T_FMT "%H:%M:%S"
 162
 163 static const unsigned short int __mon_yday[2][13] =
 164   {
 165     /* Normal years.  */
 166     { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365 },
 167     /* Leap years.  */
 168     { 0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335, 366 }
 169   };
 170 #endif
 171
 172 #if defined _LIBC
 173 /* We use this code also for the extended locale handling where the
 174    function gets as an additional argument the locale which has to be
 175    used.  To access the values we have to redefine the _NL_CURRENT
 176    macro.  */
 177 # define strptime               __strptime_l
 178 # undef _NL_CURRENT
 179 # define _NL_CURRENT(category, item) \
 180   (current->values[_NL_ITEM_INDEX (item)].string)
 181 # undef _NL_CURRENT_WORD
 182 # define _NL_CURRENT_WORD(category, item) \
 183   (current->values[_NL_ITEM_INDEX (item)].word)
 184 # define LOCALE_PARAM , locale_t locale
 185 # define LOCALE_ARG , locale
 186 # define HELPER_LOCALE_ARG , current
 187 # define ISSPACE(Ch) __isspace_l (Ch, locale)
 188 #else
 189 # define LOCALE_PARAM
 190 # define LOCALE_ARG
 191 # define HELPER_LOCALE_ARG
 192 # define ISSPACE(Ch) isspace (Ch)
 193 #endif
 194
 195
 196
 197
 198 #ifndef __isleap
 199 /* Nonzero if YEAR is a leap year (every 4 years,
 200    except every 100th isn't, and every 400th is).  */
 201 # define __isleap(year) \
 202   ((year) % 4 == 0 && ((year) % 100 != 0 || (year) % 400 == 0))
 203 #endif
 204
 205 /* Compute the day of the week.  */
 206 static void
 207 day_of_the_week (struct tm *tm)
 208 {
 209   /* We know that January 1st 1970 was a Thursday (= 4).  Compute the
 210      difference between this data in the one on TM and so determine
 211      the weekday.  */
 212   int corr_year = 1900 + tm->tm_year - (tm->tm_mon < 2);
 213   int wday = (-473
 214               + (365 * (tm->tm_year - 70))
 215               + (corr_year / 4)
 216               - ((corr_year / 4) / 25) + ((corr_year / 4) % 25 < 0)
 217               + (((corr_year / 4) / 25) / 4)
 218               + __mon_yday[0][tm->tm_mon]
 219               + tm->tm_mday - 1);
 220   tm->tm_wday = ((wday % 7) + 7) % 7;
 221 }
 222
 223 /* Compute the day of the year.  */
 224 static void
 225 day_of_the_year (struct tm *tm)
 226 {
 227   tm->tm_yday = (__mon_yday[__isleap (1900 + tm->tm_year)][tm->tm_mon]
 228                  + (tm->tm_mday - 1));
 229 }
 230
 231
 232 #ifdef _LIBC
 233 char *
 234 #else
 235 static char *
 236 #endif
 237 __strptime_internal (const char *rp, const char *fmt, struct tm *tmp,
 238                      void *statep LOCALE_PARAM)
 239 {
 240 #ifdef _LIBC
 241   struct __locale_data *const current = locale->__locales[LC_TIME];
 242 #endif
 243
 244   const char *rp_backup;
 245   const char *rp_longest;
 246   int cnt;
 247   int cnt_longest;
 248   size_t val;
 249   size_t num_eras;
 250   struct era_entry *era = NULL;
 251   enum ptime_locale_status { not, loc, raw } decided_longest;
 252   struct __strptime_state
 253   {
 254     unsigned int have_I : 1;
 255     unsigned int have_wday : 1;
 256     unsigned int have_yday : 1;
 257     unsigned int have_mon : 1;
 258     unsigned int have_mday : 1;
 259     unsigned int have_uweek : 1;
 260     unsigned int have_wweek : 1;
 261     unsigned int is_pm : 1;
 262     unsigned int want_century : 1;
 263     unsigned int want_era : 1;
 264     unsigned int want_xday : 1;
 265     enum ptime_locale_status decided : 2;
 266     signed char week_no;
 267     signed char century;
 268     int era_cnt;
 269   } s;
 270   struct tm tmb;
 271   struct tm *tm;
 272
 273   if (statep == NULL)
 274     {
 275       memset (&s, 0, sizeof (s));
 276       s.century = -1;
 277       s.era_cnt = -1;
 278 #ifdef _NL_CURRENT
 279       s.decided = not;
 280 #else
 281       s.decided = raw;
 282 #endif
 283       tm = tmp;
 284     }
 285   else
 286     {
 287       s = *(struct __strptime_state *) statep;
 288       tmb = *tmp;
 289       tm = &tmb;
 290     }
 291
 292   while (*fmt != '\0')
 293     {
 294       /* A white space in the format string matches 0 more or white
 295          space in the input string.  */
 296       if (ISSPACE (*fmt))
 297         {
 298           while (ISSPACE (*rp))
 299             ++rp;
 300           ++fmt;
 301           continue;
 302         }
 303
 304       /* Any character but `%' must be matched by the same character
 305          in the iput string.  */
 306       if (*fmt != '%')
 307         {
 308           match_char (*fmt++, *rp++);
 309           continue;
 310         }
 311
 312       ++fmt;
 313       /* We discard strftime modifiers.  */
 314       while (*fmt == '-' || *fmt == '_' || *fmt == '0'
 315              || *fmt == '^' || *fmt == '#')
 316         ++fmt;
 317
 318       /* And field width.  */
 319       while (*fmt >= '0' && *fmt <= '9')
 320         ++fmt;
 321
 322 #ifndef _NL_CURRENT
 323       /* We need this for handling the `E' modifier.  */
 324     start_over:
 325 #endif
 326
 327       /* Make back up of current processing pointer.  */
 328       rp_backup = rp;
 329
 330       switch (*fmt++)
 331         {
 332         case '%':
 333           /* Match the `%' character itself.  */
 334           match_char ('%', *rp++);
 335           break;
 336         case 'a':
 337         case 'A':
 338           /* Match day of week.  */
 339           rp_longest = NULL;
 340           decided_longest = s.decided;
 341           cnt_longest = -1;
 342           for (cnt = 0; cnt < 7; ++cnt)
 343             {
 344               const char *trp;
 345 #ifdef _NL_CURRENT
 346               if (s.decided !=raw)
 347                 {
 348                   trp = rp;
 349                   if (match_string (_NL_CURRENT (LC_TIME, DAY_1 + cnt), trp)
 350                       && trp > rp_longest)
 351                     {
 352                       rp_longest = trp;
 353                       cnt_longest = cnt;
 354                       if (s.decided == not
 355                           && strcmp (_NL_CURRENT (LC_TIME, DAY_1 + cnt),
 356                                      weekday_name[cnt]))
 357                         decided_longest = loc;
 358                     }
 359                   trp = rp;
 360                   if (match_string (_NL_CURRENT (LC_TIME, ABDAY_1 + cnt), trp)
 361                       && trp > rp_longest)
 362                     {
 363                       rp_longest = trp;
 364                       cnt_longest = cnt;
 365                       if (s.decided == not
 366                           && strcmp (_NL_CURRENT (LC_TIME, ABDAY_1 + cnt),
 367                                      ab_weekday_name[cnt]))
 368                         decided_longest = loc;
 369                     }
 370                 }
 371 #endif
 372               if (s.decided != loc
 373                   && (((trp = rp, match_string (weekday_name[cnt], trp))
 374                        && trp > rp_longest)
 375                       || ((trp = rp, match_string (ab_weekday_name[cnt], rp))
 376                           && trp > rp_longest)))
 377                 {
 378                   rp_longest = trp;
 379                   cnt_longest = cnt;
 380                   decided_longest = raw;
 381                 }
 382             }
 383           if (rp_longest == NULL)
 384             /* Does not match a weekday name.  */
 385             return NULL;
 386           rp = rp_longest;
 387           s.decided = decided_longest;
 388           tm->tm_wday = cnt_longest;
 389           s.have_wday = 1;
 390           break;
 391         case 'b':
 392         case 'B':
 393         case 'h':
 394           /* Match month name.  */
 395           rp_longest = NULL;
 396           decided_longest = s.decided;
 397           cnt_longest = -1;
 398           for (cnt = 0; cnt < 12; ++cnt)
 399             {
 400               const char *trp;
 401 #ifdef _NL_CURRENT
 402               if (s.decided !=raw)
 403                 {
 404                   trp = rp;
 405                   if (match_string (_NL_CURRENT (LC_TIME, MON_1 + cnt), trp)
 406                       && trp > rp_longest)
 407                     {
 408                       rp_longest = trp;
 409                       cnt_longest = cnt;
 410                       if (s.decided == not
 411                           && strcmp (_NL_CURRENT (LC_TIME, MON_1 + cnt),
 412                                      month_name[cnt]))
 413                         decided_longest = loc;
 414                     }
 415                   trp = rp;
 416                   if (match_string (_NL_CURRENT (LC_TIME, ABMON_1 + cnt), trp)
 417                       && trp > rp_longest)
 418                     {
 419                       rp_longest = trp;
 420                       cnt_longest = cnt;
 421                       if (s.decided == not
 422                           && strcmp (_NL_CURRENT (LC_TIME, ABMON_1 + cnt),
 423                                      ab_month_name[cnt]))
 424                         decided_longest = loc;
 425                     }
 426                 }
 427 #endif
 428               if (s.decided != loc
 429                   && (((trp = rp, match_string (month_name[cnt], trp))
 430                        && trp > rp_longest)
 431                       || ((trp = rp, match_string (ab_month_name[cnt], trp))
 432                           && trp > rp_longest)))
 433                 {
 434                   rp_longest = trp;
 435                   cnt_longest = cnt;
 436                   decided_longest = raw;
 437                 }
 438             }
 439           if (rp_longest == NULL)
 440             /* Does not match a month name.  */
 441             return NULL;
 442           rp = rp_longest;
 443           s.decided = decided_longest;
 444           tm->tm_mon = cnt_longest;
 445           s.have_mon = 1;
 446           s.want_xday = 1;
 447           break;
 448         case 'c':
 449           /* Match locale's date and time format.  */
 450 #ifdef _NL_CURRENT
 451           if (s.decided != raw)
 452             {
 453               if (!recursive (_NL_CURRENT (LC_TIME, D_T_FMT)))
 454                 {
 455                   if (s.decided == loc)
 456                     return NULL;
 457                   else
 458                     rp = rp_backup;
 459                 }
 460               else
 461                 {
 462                   if (s.decided == not &&
 463                       strcmp (_NL_CURRENT (LC_TIME, D_T_FMT), HERE_D_T_FMT))
 464                     s.decided = loc;
 465                   s.want_xday = 1;
 466                   break;
 467                 }
 468               s.decided = raw;
 469             }
 470 #endif
 471           if (!recursive (HERE_D_T_FMT))
 472             return NULL;
 473           s.want_xday = 1;
 474           break;
 475         case 'C':
 476           /* Match century number.  */
 477         match_century:
 478           get_number (0, 99, 2);
 479           s.century = val;
 480           s.want_xday = 1;
 481           break;
 482         case 'd':
 483         case 'e':
 484           /* Match day of month.  */
 485           get_number (1, 31, 2);
 486           tm->tm_mday = val;
 487           s.have_mday = 1;
 488           s.want_xday = 1;
 489           break;
 490         case 'F':
 491           if (!recursive ("%Y-%m-%d"))
 492             return NULL;
 493           s.want_xday = 1;
 494           break;
 495         case 'x':
 496 #ifdef _NL_CURRENT
 497           if (s.decided != raw)
 498             {
 499               if (!recursive (_NL_CURRENT (LC_TIME, D_FMT)))
 500                 {
 501                   if (s.decided == loc)
 502                     return NULL;
 503                   else
 504                     rp = rp_backup;
 505                 }
 506               else
 507                 {
 508                   if (s.decided == not
 509                       && strcmp (_NL_CURRENT (LC_TIME, D_FMT), HERE_D_FMT))
 510                     s.decided = loc;
 511                   s.want_xday = 1;
 512                   break;
 513                 }
 514               s.decided = raw;
 515             }
 516 #endif
 517           /* Fall through.  */
 518         case 'D':
 519           /* Match standard day format.  */
 520           if (!recursive (HERE_D_FMT))
 521             return NULL;
 522           s.want_xday = 1;
 523           break;
 524         case 'k':
 525         case 'H':
 526           /* Match hour in 24-hour clock.  */
 527           get_number (0, 23, 2);
 528           tm->tm_hour = val;
 529           s.have_I = 0;
 530           break;
 531         case 'l':
 532           /* Match hour in 12-hour clock.  GNU extension.  */
 533         case 'I':
 534           /* Match hour in 12-hour clock.  */
 535           get_number (1, 12, 2);
 536           tm->tm_hour = val % 12;
 537           s.have_I = 1;
 538           break;
 539         case 'j':
 540           /* Match day number of year.  */
 541           get_number (1, 366, 3);
 542           tm->tm_yday = val - 1;
 543           s.have_yday = 1;
 544           break;
 545         case 'm':
 546           /* Match number of month.  */
 547           get_number (1, 12, 2);
 548           tm->tm_mon = val - 1;
 549           s.have_mon = 1;
 550           s.want_xday = 1;
 551           break;
 552         case 'M':
 553           /* Match minute.  */
 554           get_number (0, 59, 2);
 555           tm->tm_min = val;
 556           break;
 557         case 'n':
 558         case 't':
 559           /* Match any white space.  */
 560           while (ISSPACE (*rp))
 561             ++rp;
 562           break;
 563         case 'p':
 564           /* Match locale's equivalent of AM/PM.  */
 565 #ifdef _NL_CURRENT
 566           if (s.decided != raw)
 567             {
 568               if (match_string (_NL_CURRENT (LC_TIME, AM_STR), rp))
 569                 {
 570                   if (strcmp (_NL_CURRENT (LC_TIME, AM_STR), HERE_AM_STR))
 571                     s.decided = loc;
 572                   s.is_pm = 0;
 573                   break;
 574                 }
 575               if (match_string (_NL_CURRENT (LC_TIME, PM_STR), rp))
 576                 {
 577                   if (strcmp (_NL_CURRENT (LC_TIME, PM_STR), HERE_PM_STR))
 578                     s.decided = loc;
 579                   s.is_pm = 1;
 580                   break;
 581                 }
 582               s.decided = raw;
 583             }
 584 #endif
 585           if (!match_string (HERE_AM_STR, rp))
 586             {
 587               if (match_string (HERE_PM_STR, rp))
 588                 s.is_pm = 1;
 589               else
 590                 return NULL;
 591             }
 592           else
 593             s.is_pm = 0;
 594           break;
 595         case 'r':
 596 #ifdef _NL_CURRENT
 597           if (s.decided != raw)
 598             {
 599               if (!recursive (_NL_CURRENT (LC_TIME, T_FMT_AMPM)))
 600                 {
 601                   if (s.decided == loc)
 602                     return NULL;
 603                   else
 604                     rp = rp_backup;
 605                 }
 606               else
 607                 {
 608                   if (s.decided == not &&
 609                       strcmp (_NL_CURRENT (LC_TIME, T_FMT_AMPM),
 610                               HERE_T_FMT_AMPM))
 611                     s.decided = loc;
 612                   break;
 613                 }
 614               s.decided = raw;
 615             }
 616 #endif
 617           if (!recursive (HERE_T_FMT_AMPM))
 618             return NULL;
 619           break;
 620         case 'R':
 621           if (!recursive ("%H:%M"))
 622             return NULL;
 623           break;
 624         case 's':
 625           {
 626             /* The number of seconds may be very high so we cannot use
 627                the `get_number' macro.  Instead read the number
 628                character for character and construct the result while
 629                doing this.  */
 630             time_t secs = 0;
 631             if (*rp < '0' || *rp > '9')
 632               /* We need at least one digit.  */
 633               return NULL;
 634
 635             do
 636               {
 637                 secs *= 10;
 638                 secs += *rp++ - '0';
 639               }
 640             while (*rp >= '0' && *rp <= '9');
 641
 642             if (localtime_r (&secs, tm) == NULL)
 643               /* Error in function.  */
 644               return NULL;
 645           }
 646           break;
 647         case 'S':
 648           get_number (0, 61, 2);
 649           tm->tm_sec = val;
 650           break;
 651         case 'X':
 652 #ifdef _NL_CURRENT
 653           if (s.decided != raw)
 654             {
 655               if (!recursive (_NL_CURRENT (LC_TIME, T_FMT)))
 656                 {
 657                   if (s.decided == loc)
 658                     return NULL;
 659                   else
 660                     rp = rp_backup;
 661                 }
 662               else
 663                 {
 664                   if (strcmp (_NL_CURRENT (LC_TIME, T_FMT), HERE_T_FMT))
 665                     s.decided = loc;
 666                   break;
 667                 }
 668               s.decided = raw;
 669             }
 670 #endif
 671           /* Fall through.  */
 672         case 'T':
 673           if (!recursive (HERE_T_FMT))
 674             return NULL;
 675           break;
 676         case 'u':
 677           get_number (1, 7, 1);
 678           tm->tm_wday = val % 7;
 679           s.have_wday = 1;
 680           break;
 681         case 'g':
 682           get_number (0, 99, 2);
 683           /* XXX This cannot determine any field in TM.  */
 684           break;
 685         case 'G':
 686           if (*rp < '0' || *rp > '9')
 687             return NULL;
 688           /* XXX Ignore the number since we would need some more
 689              information to compute a real date.  */
 690           do
 691             ++rp;
 692           while (*rp >= '0' && *rp <= '9');
 693           break;
 694         case 'U':
 695           get_number (0, 53, 2);
 696           s.week_no = val;
 697           s.have_uweek = 1;
 698           break;
 699         case 'W':
 700           get_number (0, 53, 2);
 701           s.week_no = val;
 702           s.have_wweek = 1;
 703           break;
 704         case 'V':
 705           get_number (0, 53, 2);
 706           /* XXX This cannot determine any field in TM without some
 707              information.  */
 708           break;
 709         case 'w':
 710           /* Match number of weekday.  */
 711           get_number (0, 6, 1);
 712           tm->tm_wday = val;
 713           s.have_wday = 1;
 714           break;
 715         case 'y':
 716         match_year_in_century:
 717           /* Match year within century.  */
 718           get_number (0, 99, 2);
 719           /* The "Year 2000: The Millennium Rollover" paper suggests that
 720              values in the range 69-99 refer to the twentieth century.  */
 721           tm->tm_year = val >= 69 ? val : val + 100;
 722           /* Indicate that we want to use the century, if specified.  */
 723           s.want_century = 1;
 724           s.want_xday = 1;
 725           break;
 726         case 'Y':
 727           /* Match year including century number.  */
 728           get_number (0, 9999, 4);
 729           tm->tm_year = val - 1900;
 730           s.want_century = 0;
 731           s.want_xday = 1;
 732           break;
 733         case 'Z':
 734           /* Read timezone but perform no conversion.  */
 735           while (ISSPACE (*rp))
 736             rp++;
 737           while (!ISSPACE (*rp) && *rp != '\0')
 738             rp++;
 739           break;
 740         case 'z':
 741           /* We recognize four formats:
 742              1. Two digits specify hours.
 743              2. Four digits specify hours and minutes.
 744              3. Two digits, ':', and two digits specify hours and minutes.
 745              4. 'Z' is equivalent to +0000.  */
 746           {
 747             val = 0;
 748             while (ISSPACE (*rp))
 749               ++rp;
 750             if (*rp == 'Z')
 751               {
 752                 ++rp;
 753                 tm->tm_gmtoff = 0;
 754                 break;
 755               }
 756             if (*rp != '+' && *rp != '-')
 757               return NULL;
 758             bool neg = *rp++ == '-';
 759             int n = 0;
 760             while (n < 4 && *rp >= '0' && *rp <= '9')
 761               {
 762                 val = val * 10 + *rp++ - '0';
 763                 ++n;
 764                 if (*rp == ':' && n == 2 && isdigit (*(rp + 1)))
 765                   ++rp;
 766               }
 767             if (n == 2)
 768               val *= 100;
 769             else if (n != 4)
 770               /* Only two or four digits recognized.  */
 771               return NULL;
 772             else if (val % 100 >= 60)
 773               /* Minutes valid range is 0 through 59.  */
 774               return NULL;
 775             tm->tm_gmtoff = (val / 100) * 3600 + (val % 100) * 60;
 776             if (neg)
 777               tm->tm_gmtoff = -tm->tm_gmtoff;
 778           }
 779           break;
 780         case 'E':
 781 #ifdef _NL_CURRENT
 782           switch (*fmt++)
 783             {
 784             case 'c':
 785               /* Match locale's alternate date and time format.  */
 786               if (s.decided != raw)
 787                 {
 788                   const char *fmt = _NL_CURRENT (LC_TIME, ERA_D_T_FMT);
 789
 790                   if (*fmt == '\0')
 791                     fmt = _NL_CURRENT (LC_TIME, D_T_FMT);
 792
 793                   if (!recursive (fmt))
 794                     {
 795                       if (s.decided == loc)
 796                         return NULL;
 797                       else
 798                         rp = rp_backup;
 799                     }
 800                   else
 801                     {
 802                       if (strcmp (fmt, HERE_D_T_FMT))
 803                         s.decided = loc;
 804                       s.want_xday = 1;
 805                       break;
 806                     }
 807                   s.decided = raw;
 808                 }
 809               /* The C locale has no era information, so use the
 810                  normal representation.  */
 811               if (!recursive (HERE_D_T_FMT))
 812                 return NULL;
 813               s.want_xday = 1;
 814               break;
 815             case 'C':
 816               if (s.decided != raw)
 817                 {
 818                   if (s.era_cnt >= 0)
 819                     {
 820                       era = _nl_select_era_entry (s.era_cnt HELPER_LOCALE_ARG);
 821                       if (era != NULL && match_string (era->era_name, rp))
 822                         {
 823                           s.decided = loc;
 824                           break;
 825                         }
 826                       else
 827                         return NULL;
 828                     }
 829
 830                   num_eras = _NL_CURRENT_WORD (LC_TIME,
 831                                                _NL_TIME_ERA_NUM_ENTRIES);
 832                   for (s.era_cnt = 0; s.era_cnt < (int) num_eras;
 833                        ++s.era_cnt, rp = rp_backup)
 834                     {
 835                       era = _nl_select_era_entry (s.era_cnt
 836                                                   HELPER_LOCALE_ARG);
 837                       if (era != NULL && match_string (era->era_name, rp))
 838                         {
 839                           s.decided = loc;
 840                           break;
 841                         }
 842                     }
 843                   if (s.era_cnt != (int) num_eras)
 844                     break;
 845
 846                   s.era_cnt = -1;
 847                   if (s.decided == loc)
 848                     return NULL;
 849
 850                   s.decided = raw;
 851                 }
 852               /* The C locale has no era information, so use the
 853                  normal representation.  */
 854               goto match_century;
 855             case 'y':
 856               if (s.decided != raw)
 857                 {
 858                   get_number(0, 9999, 4);
 859                   tm->tm_year = val;
 860                   s.want_era = 1;
 861                   s.want_xday = 1;
 862                   s.want_century = 1;
 863
 864                   if (s.era_cnt >= 0)
 865                     {
 866                       assert (s.decided == loc);
 867
 868                       era = _nl_select_era_entry (s.era_cnt HELPER_LOCALE_ARG);
 869                       bool match = false;
 870                       if (era != NULL)
 871                         {
 872                           int delta = ((tm->tm_year - era->offset)
 873                                        * era->absolute_direction);
 874                           match = (delta >= 0
 875                                    && delta < (((int64_t) era->stop_date[0]
 876                                                 - (int64_t) era->start_date[0])
 877                                                * era->absolute_direction));
 878                         }
 879                       if (! match)
 880                         return NULL;
 881
 882                       break;
 883                     }
 884
 885                   num_eras = _NL_CURRENT_WORD (LC_TIME,
 886                                                _NL_TIME_ERA_NUM_ENTRIES);
 887                   for (s.era_cnt = 0; s.era_cnt < (int) num_eras; ++s.era_cnt)
 888                     {
 889                       era = _nl_select_era_entry (s.era_cnt
 890                                                   HELPER_LOCALE_ARG);
 891                       if (era != NULL)
 892                         {
 893                           int delta = ((tm->tm_year - era->offset)
 894                                        * era->absolute_direction);
 895                           if (delta >= 0
 896                               && delta < (((int64_t) era->stop_date[0]
 897                                            - (int64_t) era->start_date[0])
 898                                           * era->absolute_direction))
 899                             {
 900                               s.decided = loc;
 901                               break;
 902                             }
 903                         }
 904                     }
 905                   if (s.era_cnt != (int) num_eras)
 906                     break;
 907
 908                   s.era_cnt = -1;
 909                   if (s.decided == loc)
 910                     return NULL;
 911
 912                   s.decided = raw;
 913                 }
 914
 915               goto match_year_in_century;
 916             case 'Y':
 917               if (s.decided != raw)
 918                 {
 919                   num_eras = _NL_CURRENT_WORD (LC_TIME,
 920                                                _NL_TIME_ERA_NUM_ENTRIES);
 921                   for (s.era_cnt = 0; s.era_cnt < (int) num_eras;
 922                        ++s.era_cnt, rp = rp_backup)
 923                     {
 924                       era = _nl_select_era_entry (s.era_cnt HELPER_LOCALE_ARG);
 925                       if (era != NULL && recursive (era->era_format))
 926                         break;
 927                     }
 928                   if (s.era_cnt == (int) num_eras)
 929                     {
 930                       s.era_cnt = -1;
 931                       if (s.decided == loc)
 932                         return NULL;
 933                       else
 934                         rp = rp_backup;
 935                     }
 936                   else
 937                     {
 938                       s.decided = loc;
 939                       break;
 940                     }
 941
 942                   s.decided = raw;
 943                 }
 944               get_number (0, 9999, 4);
 945               tm->tm_year = val - 1900;
 946               s.want_century = 0;
 947               s.want_xday = 1;
 948               break;
 949             case 'x':
 950               if (s.decided != raw)
 951                 {
 952                   const char *fmt = _NL_CURRENT (LC_TIME, ERA_D_FMT);
 953
 954                   if (*fmt == '\0')
 955                     fmt = _NL_CURRENT (LC_TIME, D_FMT);
 956
 957                   if (!recursive (fmt))
 958                     {
 959                       if (s.decided == loc)
 960                         return NULL;
 961                       else
 962                         rp = rp_backup;
 963                     }
 964                   else
 965                     {
 966                       if (strcmp (fmt, HERE_D_FMT))
 967                         s.decided = loc;
 968                       break;
 969                     }
 970                   s.decided = raw;
 971                 }
 972               if (!recursive (HERE_D_FMT))
 973                 return NULL;
 974               break;
 975             case 'X':
 976               if (s.decided != raw)
 977                 {
 978                   const char *fmt = _NL_CURRENT (LC_TIME, ERA_T_FMT);
 979
 980                   if (*fmt == '\0')
 981                     fmt = _NL_CURRENT (LC_TIME, T_FMT);
 982
 983                   if (!recursive (fmt))
 984                     {
 985                       if (s.decided == loc)
 986                         return NULL;
 987                       else
 988                         rp = rp_backup;
 989                     }
 990                   else
 991                     {
 992                       if (strcmp (fmt, HERE_T_FMT))
 993                         s.decided = loc;
 994                       break;
 995                     }
 996                   s.decided = raw;
 997                 }
 998               if (!recursive (HERE_T_FMT))
 999                 return NULL;
1000               break;
1001             default:
1002               return NULL;
1003             }
1004           break;
1005 #else
1006           /* We have no information about the era format.  Just use
1007              the normal format.  */
1008           if (*fmt != 'c' && *fmt != 'C' && *fmt != 'y' && *fmt != 'Y'
1009               && *fmt != 'x' && *fmt != 'X')
1010             /* This is an illegal format.  */
1011             return NULL;
1012
1013           goto start_over;
1014 #endif
1015         case 'O':
1016           switch (*fmt++)
1017             {
1018             case 'd':
1019             case 'e':
1020               /* Match day of month using alternate numeric symbols.  */
1021               get_alt_number (1, 31, 2);
1022               tm->tm_mday = val;
1023               s.have_mday = 1;
1024               s.want_xday = 1;
1025               break;
1026             case 'H':
1027               /* Match hour in 24-hour clock using alternate numeric
1028                  symbols.  */
1029               get_alt_number (0, 23, 2);
1030               tm->tm_hour = val;
1031               s.have_I = 0;
1032               break;
1033             case 'I':
1034               /* Match hour in 12-hour clock using alternate numeric
1035                  symbols.  */
1036               get_alt_number (1, 12, 2);
1037               tm->tm_hour = val % 12;
1038               s.have_I = 1;
1039               break;
1040             case 'm':
1041               /* Match month using alternate numeric symbols.  */
1042               get_alt_number (1, 12, 2);
1043               tm->tm_mon = val - 1;
1044               s.have_mon = 1;
1045               s.want_xday = 1;
1046               break;
1047             case 'M':
1048               /* Match minutes using alternate numeric symbols.  */
1049               get_alt_number (0, 59, 2);
1050               tm->tm_min = val;
1051               break;
1052             case 'S':
1053               /* Match seconds using alternate numeric symbols.  */
1054               get_alt_number (0, 61, 2);
1055               tm->tm_sec = val;
1056               break;
1057             case 'U':
1058               get_alt_number (0, 53, 2);
1059               s.week_no = val;
1060               s.have_uweek = 1;
1061               break;
1062             case 'W':
1063               get_alt_number (0, 53, 2);
1064               s.week_no = val;
1065               s.have_wweek = 1;
1066               break;
1067             case 'V':
1068               get_alt_number (0, 53, 2);
1069               /* XXX This cannot determine any field in TM without
1070                  further information.  */
1071               break;
1072             case 'w':
1073               /* Match number of weekday using alternate numeric symbols.  */
1074               get_alt_number (0, 6, 1);
1075               tm->tm_wday = val;
1076               s.have_wday = 1;
1077               break;
1078             case 'y':
1079               /* Match year within century using alternate numeric symbols.  */
1080               get_alt_number (0, 99, 2);
1081               tm->tm_year = val >= 69 ? val : val + 100;
1082               s.want_xday = 1;
1083               break;
1084             default:
1085               return NULL;
1086             }
1087           break;
1088         default:
1089           return NULL;
1090         }
1091     }
1092
1093   if (statep != NULL)
1094     {
1095       /* Recursive invocation, returning success, so
1096          update parent's struct tm and state.  */
1097       *(struct __strptime_state *) statep = s;
1098       *tmp = tmb;
1099       return (char *) rp;
1100     }
1101
1102   if (s.have_I && s.is_pm)
1103     tm->tm_hour += 12;
1104
1105   if (s.century != -1)
1106     {
1107       if (s.want_century)
1108         tm->tm_year = tm->tm_year % 100 + (s.century - 19) * 100;
1109       else
1110         /* Only the century, but not the year.  Strange, but so be it.  */
1111         tm->tm_year = (s.century - 19) * 100;
1112     }
1113
1114   if (s.era_cnt != -1)
1115     {
1116       era = _nl_select_era_entry (s.era_cnt HELPER_LOCALE_ARG);
1117       if (era == NULL)
1118         return NULL;
1119       if (s.want_era)
1120         tm->tm_year = (era->start_date[0]
1121                        + ((tm->tm_year - era->offset)
1122                           * era->absolute_direction));
1123       else
1124         /* Era start year assumed.  */
1125         tm->tm_year = era->start_date[0];
1126     }
1127   else
1128     if (s.want_era)
1129       {
1130         /* No era found but we have seen an E modifier.  Rectify some
1131            values.  */
1132         if (s.want_century && s.century == -1 && tm->tm_year < 69)
1133           tm->tm_year += 100;
1134       }
1135
1136   if (s.want_xday && !s.have_wday)
1137     {
1138       if ( !(s.have_mon && s.have_mday) && s.have_yday)
1139         {
1140           /* We don't have tm_mon and/or tm_mday, compute them.  */
1141           int t_mon = 0;
1142           while (__mon_yday[__isleap(1900 + tm->tm_year)][t_mon] <= tm->tm_yday)
1143               t_mon++;
1144           if (!s.have_mon)
1145               tm->tm_mon = t_mon - 1;
1146           if (!s.have_mday)
1147               tm->tm_mday =
1148                 (tm->tm_yday
1149                  - __mon_yday[__isleap(1900 + tm->tm_year)][t_mon - 1] + 1);
1150           s.have_mon = 1;
1151           s.have_mday = 1;
1152         }
1153       /* Don't crash in day_of_the_week if tm_mon is uninitialized.  */
1154       if (s.have_mon || (unsigned) tm->tm_mon <= 11)
1155         day_of_the_week (tm);
1156     }
1157
1158   if (s.want_xday && !s.have_yday && (s.have_mon || (unsigned) tm->tm_mon <= 11))
1159     day_of_the_year (tm);
1160
1161   if ((s.have_uweek || s.have_wweek) && s.have_wday)
1162     {
1163       int save_wday = tm->tm_wday;
1164       int save_mday = tm->tm_mday;
1165       int save_mon = tm->tm_mon;
1166       int w_offset = s.have_uweek ? 0 : 1;
1167
1168       tm->tm_mday = 1;
1169       tm->tm_mon = 0;
1170       day_of_the_week (tm);
1171       if (s.have_mday)
1172         tm->tm_mday = save_mday;
1173       if (s.have_mon)
1174         tm->tm_mon = save_mon;
1175
1176       if (!s.have_yday)
1177         tm->tm_yday = ((7 - (tm->tm_wday - w_offset)) % 7
1178                        + (s.week_no - 1) * 7
1179                        + (save_wday - w_offset + 7) % 7);
1180
1181       if (!s.have_mday || !s.have_mon)
1182         {
1183           int t_mon = 0;
1184           while (__mon_yday[__isleap(1900 + tm->tm_year)][t_mon]
1185                  <= tm->tm_yday)
1186             t_mon++;
1187           if (!s.have_mon)
1188             tm->tm_mon = t_mon - 1;
1189           if (!s.have_mday)
1190               tm->tm_mday =
1191                 (tm->tm_yday
1192                  - __mon_yday[__isleap(1900 + tm->tm_year)][t_mon - 1] + 1);
1193         }
1194
1195       tm->tm_wday = save_wday;
1196     }
1197
1198   return (char *) rp;
1199 }
1200
1201
1202 char *
1203 strptime (const char *buf, const char *format, struct tm *tm LOCALE_PARAM)
1204 {
1205   return __strptime_internal (buf, format, tm, NULL LOCALE_ARG);
1206 }
1207
1208 #ifdef _LIBC
1209 weak_alias (__strptime_l, strptime_l)
1210 #endif