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 internal_function
 235 #else
 236 static char *
 237 #endif
 238 __strptime_internal (const char *rp, const char *fmt, struct tm *tmp,
 239                      void *statep LOCALE_PARAM)
 240 {
 241 #ifdef _LIBC
 242   struct __locale_data *const current = locale->__locales[LC_TIME];
 243 #endif
 244
 245   const char *rp_backup;
 246   const char *rp_longest;
 247   int cnt;
 248   int cnt_longest;
 249   size_t val;
 250   size_t num_eras;
 251   struct era_entry *era = NULL;
 252   enum ptime_locale_status { not, loc, raw } decided_longest;
 253   struct __strptime_state
 254   {
 255     unsigned int have_I : 1;
 256     unsigned int have_wday : 1;
 257     unsigned int have_yday : 1;
 258     unsigned int have_mon : 1;
 259     unsigned int have_mday : 1;
 260     unsigned int have_uweek : 1;
 261     unsigned int have_wweek : 1;
 262     unsigned int is_pm : 1;
 263     unsigned int want_century : 1;
 264     unsigned int want_era : 1;
 265     unsigned int want_xday : 1;
 266     enum ptime_locale_status decided : 2;
 267     signed char week_no;
 268     signed char century;
 269     int era_cnt;
 270   } s;
 271   struct tm tmb;
 272   struct tm *tm;
 273
 274   if (statep == NULL)
 275     {
 276       memset (&s, 0, sizeof (s));
 277       s.century = -1;
 278       s.era_cnt = -1;
 279 #ifdef _NL_CURRENT
 280       s.decided = not;
 281 #else
 282       s.decided = raw;
 283 #endif
 284       tm = tmp;
 285     }
 286   else
 287     {
 288       s = *(struct __strptime_state *) statep;
 289       tmb = *tmp;
 290       tm = &tmb;
 291     }
 292
 293   while (*fmt != '\0')
 294     {
 295       /* A white space in the format string matches 0 more or white
 296          space in the input string.  */
 297       if (ISSPACE (*fmt))
 298         {
 299           while (ISSPACE (*rp))
 300             ++rp;
 301           ++fmt;
 302           continue;
 303         }
 304
 305       /* Any character but `%' must be matched by the same character
 306          in the iput string.  */
 307       if (*fmt != '%')
 308         {
 309           match_char (*fmt++, *rp++);
 310           continue;
 311         }
 312
 313       ++fmt;
 314       /* We discard strftime modifiers.  */
 315       while (*fmt == '-' || *fmt == '_' || *fmt == '0'
 316              || *fmt == '^' || *fmt == '#')
 317         ++fmt;
 318
 319       /* And field width.  */
 320       while (*fmt >= '0' && *fmt <= '9')
 321         ++fmt;
 322
 323 #ifndef _NL_CURRENT
 324       /* We need this for handling the `E' modifier.  */
 325     start_over:
 326 #endif
 327
 328       /* Make back up of current processing pointer.  */
 329       rp_backup = rp;
 330
 331       switch (*fmt++)
 332         {
 333         case '%':
 334           /* Match the `%' character itself.  */
 335           match_char ('%', *rp++);
 336           break;
 337         case 'a':
 338         case 'A':
 339           /* Match day of week.  */
 340           rp_longest = NULL;
 341           decided_longest = s.decided;
 342           cnt_longest = -1;
 343           for (cnt = 0; cnt < 7; ++cnt)
 344             {
 345               const char *trp;
 346 #ifdef _NL_CURRENT
 347               if (s.decided !=raw)
 348                 {
 349                   trp = rp;
 350                   if (match_string (_NL_CURRENT (LC_TIME, DAY_1 + cnt), trp)
 351                       && trp > rp_longest)
 352                     {
 353                       rp_longest = trp;
 354                       cnt_longest = cnt;
 355                       if (s.decided == not
 356                           && strcmp (_NL_CURRENT (LC_TIME, DAY_1 + cnt),
 357                                      weekday_name[cnt]))
 358                         decided_longest = loc;
 359                     }
 360                   trp = rp;
 361                   if (match_string (_NL_CURRENT (LC_TIME, ABDAY_1 + cnt), trp)
 362                       && trp > rp_longest)
 363                     {
 364                       rp_longest = trp;
 365                       cnt_longest = cnt;
 366                       if (s.decided == not
 367                           && strcmp (_NL_CURRENT (LC_TIME, ABDAY_1 + cnt),
 368                                      ab_weekday_name[cnt]))
 369                         decided_longest = loc;
 370                     }
 371                 }
 372 #endif
 373               if (s.decided != loc
 374                   && (((trp = rp, match_string (weekday_name[cnt], trp))
 375                        && trp > rp_longest)
 376                       || ((trp = rp, match_string (ab_weekday_name[cnt], rp))
 377                           && trp > rp_longest)))
 378                 {
 379                   rp_longest = trp;
 380                   cnt_longest = cnt;
 381                   decided_longest = raw;
 382                 }
 383             }
 384           if (rp_longest == NULL)
 385             /* Does not match a weekday name.  */
 386             return NULL;
 387           rp = rp_longest;
 388           s.decided = decided_longest;
 389           tm->tm_wday = cnt_longest;
 390           s.have_wday = 1;
 391           break;
 392         case 'b':
 393         case 'B':
 394         case 'h':
 395           /* Match month name.  */
 396           rp_longest = NULL;
 397           decided_longest = s.decided;
 398           cnt_longest = -1;
 399           for (cnt = 0; cnt < 12; ++cnt)
 400             {
 401               const char *trp;
 402 #ifdef _NL_CURRENT
 403               if (s.decided !=raw)
 404                 {
 405                   trp = rp;
 406                   if (match_string (_NL_CURRENT (LC_TIME, MON_1 + cnt), trp)
 407                       && trp > rp_longest)
 408                     {
 409                       rp_longest = trp;
 410                       cnt_longest = cnt;
 411                       if (s.decided == not
 412                           && strcmp (_NL_CURRENT (LC_TIME, MON_1 + cnt),
 413                                      month_name[cnt]))
 414                         decided_longest = loc;
 415                     }
 416                   trp = rp;
 417                   if (match_string (_NL_CURRENT (LC_TIME, ABMON_1 + cnt), trp)
 418                       && trp > rp_longest)
 419                     {
 420                       rp_longest = trp;
 421                       cnt_longest = cnt;
 422                       if (s.decided == not
 423                           && strcmp (_NL_CURRENT (LC_TIME, ABMON_1 + cnt),
 424                                      ab_month_name[cnt]))
 425                         decided_longest = loc;
 426                     }
 427                 }
 428 #endif
 429               if (s.decided != loc
 430                   && (((trp = rp, match_string (month_name[cnt], trp))
 431                        && trp > rp_longest)
 432                       || ((trp = rp, match_string (ab_month_name[cnt], trp))
 433                           && trp > rp_longest)))
 434                 {
 435                   rp_longest = trp;
 436                   cnt_longest = cnt;
 437                   decided_longest = raw;
 438                 }
 439             }
 440           if (rp_longest == NULL)
 441             /* Does not match a month name.  */
 442             return NULL;
 443           rp = rp_longest;
 444           s.decided = decided_longest;
 445           tm->tm_mon = cnt_longest;
 446           s.have_mon = 1;
 447           s.want_xday = 1;
 448           break;
 449         case 'c':
 450           /* Match locale's date and time format.  */
 451 #ifdef _NL_CURRENT
 452           if (s.decided != raw)
 453             {
 454               if (!recursive (_NL_CURRENT (LC_TIME, D_T_FMT)))
 455                 {
 456                   if (s.decided == loc)
 457                     return NULL;
 458                   else
 459                     rp = rp_backup;
 460                 }
 461               else
 462                 {
 463                   if (s.decided == not &&
 464                       strcmp (_NL_CURRENT (LC_TIME, D_T_FMT), HERE_D_T_FMT))
 465                     s.decided = loc;
 466                   s.want_xday = 1;
 467                   break;
 468                 }
 469               s.decided = raw;
 470             }
 471 #endif
 472           if (!recursive (HERE_D_T_FMT))
 473             return NULL;
 474           s.want_xday = 1;
 475           break;
 476         case 'C':
 477           /* Match century number.  */
 478         match_century:
 479           get_number (0, 99, 2);
 480           s.century = val;
 481           s.want_xday = 1;
 482           break;
 483         case 'd':
 484         case 'e':
 485           /* Match day of month.  */
 486           get_number (1, 31, 2);
 487           tm->tm_mday = val;
 488           s.have_mday = 1;
 489           s.want_xday = 1;
 490           break;
 491         case 'F':
 492           if (!recursive ("%Y-%m-%d"))
 493             return NULL;
 494           s.want_xday = 1;
 495           break;
 496         case 'x':
 497 #ifdef _NL_CURRENT
 498           if (s.decided != raw)
 499             {
 500               if (!recursive (_NL_CURRENT (LC_TIME, D_FMT)))
 501                 {
 502                   if (s.decided == loc)
 503                     return NULL;
 504                   else
 505                     rp = rp_backup;
 506                 }
 507               else
 508                 {
 509                   if (s.decided == not
 510                       && strcmp (_NL_CURRENT (LC_TIME, D_FMT), HERE_D_FMT))
 511                     s.decided = loc;
 512                   s.want_xday = 1;
 513                   break;
 514                 }
 515               s.decided = raw;
 516             }
 517 #endif
 518           /* Fall through.  */
 519         case 'D':
 520           /* Match standard day format.  */
 521           if (!recursive (HERE_D_FMT))
 522             return NULL;
 523           s.want_xday = 1;
 524           break;
 525         case 'k':
 526         case 'H':
 527           /* Match hour in 24-hour clock.  */
 528           get_number (0, 23, 2);
 529           tm->tm_hour = val;
 530           s.have_I = 0;
 531           break;
 532         case 'l':
 533           /* Match hour in 12-hour clock.  GNU extension.  */
 534         case 'I':
 535           /* Match hour in 12-hour clock.  */
 536           get_number (1, 12, 2);
 537           tm->tm_hour = val % 12;
 538           s.have_I = 1;
 539           break;
 540         case 'j':
 541           /* Match day number of year.  */
 542           get_number (1, 366, 3);
 543           tm->tm_yday = val - 1;
 544           s.have_yday = 1;
 545           break;
 546         case 'm':
 547           /* Match number of month.  */
 548           get_number (1, 12, 2);
 549           tm->tm_mon = val - 1;
 550           s.have_mon = 1;
 551           s.want_xday = 1;
 552           break;
 553         case 'M':
 554           /* Match minute.  */
 555           get_number (0, 59, 2);
 556           tm->tm_min = val;
 557           break;
 558         case 'n':
 559         case 't':
 560           /* Match any white space.  */
 561           while (ISSPACE (*rp))
 562             ++rp;
 563           break;
 564         case 'p':
 565           /* Match locale's equivalent of AM/PM.  */
 566 #ifdef _NL_CURRENT
 567           if (s.decided != raw)
 568             {
 569               if (match_string (_NL_CURRENT (LC_TIME, AM_STR), rp))
 570                 {
 571                   if (strcmp (_NL_CURRENT (LC_TIME, AM_STR), HERE_AM_STR))
 572                     s.decided = loc;
 573                   s.is_pm = 0;
 574                   break;
 575                 }
 576               if (match_string (_NL_CURRENT (LC_TIME, PM_STR), rp))
 577                 {
 578                   if (strcmp (_NL_CURRENT (LC_TIME, PM_STR), HERE_PM_STR))
 579                     s.decided = loc;
 580                   s.is_pm = 1;
 581                   break;
 582                 }
 583               s.decided = raw;
 584             }
 585 #endif
 586           if (!match_string (HERE_AM_STR, rp))
 587             {
 588               if (match_string (HERE_PM_STR, rp))
 589                 s.is_pm = 1;
 590               else
 591                 return NULL;
 592             }
 593           else
 594             s.is_pm = 0;
 595           break;
 596         case 'r':
 597 #ifdef _NL_CURRENT
 598           if (s.decided != raw)
 599             {
 600               if (!recursive (_NL_CURRENT (LC_TIME, T_FMT_AMPM)))
 601                 {
 602                   if (s.decided == loc)
 603                     return NULL;
 604                   else
 605                     rp = rp_backup;
 606                 }
 607               else
 608                 {
 609                   if (s.decided == not &&
 610                       strcmp (_NL_CURRENT (LC_TIME, T_FMT_AMPM),
 611                               HERE_T_FMT_AMPM))
 612                     s.decided = loc;
 613                   break;
 614                 }
 615               s.decided = raw;
 616             }
 617 #endif
 618           if (!recursive (HERE_T_FMT_AMPM))
 619             return NULL;
 620           break;
 621         case 'R':
 622           if (!recursive ("%H:%M"))
 623             return NULL;
 624           break;
 625         case 's':
 626           {
 627             /* The number of seconds may be very high so we cannot use
 628                the `get_number' macro.  Instead read the number
 629                character for character and construct the result while
 630                doing this.  */
 631             time_t secs = 0;
 632             if (*rp < '0' || *rp > '9')
 633               /* We need at least one digit.  */
 634               return NULL;
 635
 636             do
 637               {
 638                 secs *= 10;
 639                 secs += *rp++ - '0';
 640               }
 641             while (*rp >= '0' && *rp <= '9');
 642
 643             if (localtime_r (&secs, tm) == NULL)
 644               /* Error in function.  */
 645               return NULL;
 646           }
 647           break;
 648         case 'S':
 649           get_number (0, 61, 2);
 650           tm->tm_sec = val;
 651           break;
 652         case 'X':
 653 #ifdef _NL_CURRENT
 654           if (s.decided != raw)
 655             {
 656               if (!recursive (_NL_CURRENT (LC_TIME, T_FMT)))
 657                 {
 658                   if (s.decided == loc)
 659                     return NULL;
 660                   else
 661                     rp = rp_backup;
 662                 }
 663               else
 664                 {
 665                   if (strcmp (_NL_CURRENT (LC_TIME, T_FMT), HERE_T_FMT))
 666                     s.decided = loc;
 667                   break;
 668                 }
 669               s.decided = raw;
 670             }
 671 #endif
 672           /* Fall through.  */
 673         case 'T':
 674           if (!recursive (HERE_T_FMT))
 675             return NULL;
 676           break;
 677         case 'u':
 678           get_number (1, 7, 1);
 679           tm->tm_wday = val % 7;
 680           s.have_wday = 1;
 681           break;
 682         case 'g':
 683           get_number (0, 99, 2);
 684           /* XXX This cannot determine any field in TM.  */
 685           break;
 686         case 'G':
 687           if (*rp < '0' || *rp > '9')
 688             return NULL;
 689           /* XXX Ignore the number since we would need some more
 690              information to compute a real date.  */
 691           do
 692             ++rp;
 693           while (*rp >= '0' && *rp <= '9');
 694           break;
 695         case 'U':
 696           get_number (0, 53, 2);
 697           s.week_no = val;
 698           s.have_uweek = 1;
 699           break;
 700         case 'W':
 701           get_number (0, 53, 2);
 702           s.week_no = val;
 703           s.have_wweek = 1;
 704           break;
 705         case 'V':
 706           get_number (0, 53, 2);
 707           /* XXX This cannot determine any field in TM without some
 708              information.  */
 709           break;
 710         case 'w':
 711           /* Match number of weekday.  */
 712           get_number (0, 6, 1);
 713           tm->tm_wday = val;
 714           s.have_wday = 1;
 715           break;
 716         case 'y':
 717         match_year_in_century:
 718           /* Match year within century.  */
 719           get_number (0, 99, 2);
 720           /* The "Year 2000: The Millennium Rollover" paper suggests that
 721              values in the range 69-99 refer to the twentieth century.  */
 722           tm->tm_year = val >= 69 ? val : val + 100;
 723           /* Indicate that we want to use the century, if specified.  */
 724           s.want_century = 1;
 725           s.want_xday = 1;
 726           break;
 727         case 'Y':
 728           /* Match year including century number.  */
 729           get_number (0, 9999, 4);
 730           tm->tm_year = val - 1900;
 731           s.want_century = 0;
 732           s.want_xday = 1;
 733           break;
 734         case 'Z':
 735           /* Read timezone but perform no conversion.  */
 736           while (ISSPACE (*rp))
 737             rp++;
 738           while (!ISSPACE (*rp) && *rp != '\0')
 739             rp++;
 740           break;
 741         case 'z':
 742           /* We recognize four formats:
 743              1. Two digits specify hours.
 744              2. Four digits specify hours and minutes.
 745              3. Two digits, ':', and two digits specify hours and minutes.
 746              4. 'Z' is equivalent to +0000.  */
 747           {
 748             val = 0;
 749             while (ISSPACE (*rp))
 750               ++rp;
 751             if (*rp == 'Z')
 752               {
 753                 ++rp;
 754                 tm->tm_gmtoff = 0;
 755                 break;
 756               }
 757             if (*rp != '+' && *rp != '-')
 758               return NULL;
 759             bool neg = *rp++ == '-';
 760             int n = 0;
 761             while (n < 4 && *rp >= '0' && *rp <= '9')
 762               {
 763                 val = val * 10 + *rp++ - '0';
 764                 ++n;
 765                 if (*rp == ':' && n == 2 && isdigit (*(rp + 1)))
 766                   ++rp;
 767               }
 768             if (n == 2)
 769               val *= 100;
 770             else if (n != 4)
 771               /* Only two or four digits recognized.  */
 772               return NULL;
 773             else if (val % 100 >= 60)
 774               /* Minutes valid range is 0 through 59.  */
 775               return NULL;
 776             tm->tm_gmtoff = (val / 100) * 3600 + (val % 100) * 60;
 777             if (neg)
 778               tm->tm_gmtoff = -tm->tm_gmtoff;
 779           }
 780           break;
 781         case 'E':
 782 #ifdef _NL_CURRENT
 783           switch (*fmt++)
 784             {
 785             case 'c':
 786               /* Match locale's alternate date and time format.  */
 787               if (s.decided != raw)
 788                 {
 789                   const char *fmt = _NL_CURRENT (LC_TIME, ERA_D_T_FMT);
 790
 791                   if (*fmt == '\0')
 792                     fmt = _NL_CURRENT (LC_TIME, D_T_FMT);
 793
 794                   if (!recursive (fmt))
 795                     {
 796                       if (s.decided == loc)
 797                         return NULL;
 798                       else
 799                         rp = rp_backup;
 800                     }
 801                   else
 802                     {
 803                       if (strcmp (fmt, HERE_D_T_FMT))
 804                         s.decided = loc;
 805                       s.want_xday = 1;
 806                       break;
 807                     }
 808                   s.decided = raw;
 809                 }
 810               /* The C locale has no era information, so use the
 811                  normal representation.  */
 812               if (!recursive (HERE_D_T_FMT))
 813                 return NULL;
 814               s.want_xday = 1;
 815               break;
 816             case 'C':
 817               if (s.decided != raw)
 818                 {
 819                   if (s.era_cnt >= 0)
 820                     {
 821                       era = _nl_select_era_entry (s.era_cnt HELPER_LOCALE_ARG);
 822                       if (era != NULL && match_string (era->era_name, rp))
 823                         {
 824                           s.decided = loc;
 825                           break;
 826                         }
 827                       else
 828                         return NULL;
 829                     }
 830
 831                   num_eras = _NL_CURRENT_WORD (LC_TIME,
 832                                                _NL_TIME_ERA_NUM_ENTRIES);
 833                   for (s.era_cnt = 0; s.era_cnt < (int) num_eras;
 834                        ++s.era_cnt, rp = rp_backup)
 835                     {
 836                       era = _nl_select_era_entry (s.era_cnt
 837                                                   HELPER_LOCALE_ARG);
 838                       if (era != NULL && match_string (era->era_name, rp))
 839                         {
 840                           s.decided = loc;
 841                           break;
 842                         }
 843                     }
 844                   if (s.era_cnt != (int) num_eras)
 845                     break;
 846
 847                   s.era_cnt = -1;
 848                   if (s.decided == loc)
 849                     return NULL;
 850
 851                   s.decided = raw;
 852                 }
 853               /* The C locale has no era information, so use the
 854                  normal representation.  */
 855               goto match_century;
 856             case 'y':
 857               if (s.decided != raw)
 858                 {
 859                   get_number(0, 9999, 4);
 860                   tm->tm_year = val;
 861                   s.want_era = 1;
 862                   s.want_xday = 1;
 863                   s.want_century = 1;
 864
 865                   if (s.era_cnt >= 0)
 866                     {
 867                       assert (s.decided == loc);
 868
 869                       era = _nl_select_era_entry (s.era_cnt HELPER_LOCALE_ARG);
 870                       bool match = false;
 871                       if (era != NULL)
 872                         {
 873                           int delta = ((tm->tm_year - era->offset)
 874                                        * era->absolute_direction);
 875                           match = (delta >= 0
 876                                    && delta < (((int64_t) era->stop_date[0]
 877                                                 - (int64_t) era->start_date[0])
 878                                                * era->absolute_direction));
 879                         }
 880                       if (! match)
 881                         return NULL;
 882
 883                       break;
 884                     }
 885
 886                   num_eras = _NL_CURRENT_WORD (LC_TIME,
 887                                                _NL_TIME_ERA_NUM_ENTRIES);
 888                   for (s.era_cnt = 0; s.era_cnt < (int) num_eras; ++s.era_cnt)
 889                     {
 890                       era = _nl_select_era_entry (s.era_cnt
 891                                                   HELPER_LOCALE_ARG);
 892                       if (era != NULL)
 893                         {
 894                           int delta = ((tm->tm_year - era->offset)
 895                                        * era->absolute_direction);
 896                           if (delta >= 0
 897                               && delta < (((int64_t) era->stop_date[0]
 898                                            - (int64_t) era->start_date[0])
 899                                           * era->absolute_direction))
 900                             {
 901                               s.decided = loc;
 902                               break;
 903                             }
 904                         }
 905                     }
 906                   if (s.era_cnt != (int) num_eras)
 907                     break;
 908
 909                   s.era_cnt = -1;
 910                   if (s.decided == loc)
 911                     return NULL;
 912
 913                   s.decided = raw;
 914                 }
 915
 916               goto match_year_in_century;
 917             case 'Y':
 918               if (s.decided != raw)
 919                 {
 920                   num_eras = _NL_CURRENT_WORD (LC_TIME,
 921                                                _NL_TIME_ERA_NUM_ENTRIES);
 922                   for (s.era_cnt = 0; s.era_cnt < (int) num_eras;
 923                        ++s.era_cnt, rp = rp_backup)
 924                     {
 925                       era = _nl_select_era_entry (s.era_cnt HELPER_LOCALE_ARG);
 926                       if (era != NULL && recursive (era->era_format))
 927                         break;
 928                     }
 929                   if (s.era_cnt == (int) num_eras)
 930                     {
 931                       s.era_cnt = -1;
 932                       if (s.decided == loc)
 933                         return NULL;
 934                       else
 935                         rp = rp_backup;
 936                     }
 937                   else
 938                     {
 939                       s.decided = loc;
 940                       break;
 941                     }
 942
 943                   s.decided = raw;
 944                 }
 945               get_number (0, 9999, 4);
 946               tm->tm_year = val - 1900;
 947               s.want_century = 0;
 948               s.want_xday = 1;
 949               break;
 950             case 'x':
 951               if (s.decided != raw)
 952                 {
 953                   const char *fmt = _NL_CURRENT (LC_TIME, ERA_D_FMT);
 954
 955                   if (*fmt == '\0')
 956                     fmt = _NL_CURRENT (LC_TIME, D_FMT);
 957
 958                   if (!recursive (fmt))
 959                     {
 960                       if (s.decided == loc)
 961                         return NULL;
 962                       else
 963                         rp = rp_backup;
 964                     }
 965                   else
 966                     {
 967                       if (strcmp (fmt, HERE_D_FMT))
 968                         s.decided = loc;
 969                       break;
 970                     }
 971                   s.decided = raw;
 972                 }
 973               if (!recursive (HERE_D_FMT))
 974                 return NULL;
 975               break;
 976             case 'X':
 977               if (s.decided != raw)
 978                 {
 979                   const char *fmt = _NL_CURRENT (LC_TIME, ERA_T_FMT);
 980
 981                   if (*fmt == '\0')
 982                     fmt = _NL_CURRENT (LC_TIME, T_FMT);
 983
 984                   if (!recursive (fmt))
 985                     {
 986                       if (s.decided == loc)
 987                         return NULL;
 988                       else
 989                         rp = rp_backup;
 990                     }
 991                   else
 992                     {
 993                       if (strcmp (fmt, HERE_T_FMT))
 994                         s.decided = loc;
 995                       break;
 996                     }
 997                   s.decided = raw;
 998                 }
 999               if (!recursive (HERE_T_FMT))
1000                 return NULL;
1001               break;
1002             default:
1003               return NULL;
1004             }
1005           break;
1006 #else
1007           /* We have no information about the era format.  Just use
1008              the normal format.  */
1009           if (*fmt != 'c' && *fmt != 'C' && *fmt != 'y' && *fmt != 'Y'
1010               && *fmt != 'x' && *fmt != 'X')
1011             /* This is an illegal format.  */
1012             return NULL;
1013
1014           goto start_over;
1015 #endif
1016         case 'O':
1017           switch (*fmt++)
1018             {
1019             case 'd':
1020             case 'e':
1021               /* Match day of month using alternate numeric symbols.  */
1022               get_alt_number (1, 31, 2);
1023               tm->tm_mday = val;
1024               s.have_mday = 1;
1025               s.want_xday = 1;
1026               break;
1027             case 'H':
1028               /* Match hour in 24-hour clock using alternate numeric
1029                  symbols.  */
1030               get_alt_number (0, 23, 2);
1031               tm->tm_hour = val;
1032               s.have_I = 0;
1033               break;
1034             case 'I':
1035               /* Match hour in 12-hour clock using alternate numeric
1036                  symbols.  */
1037               get_alt_number (1, 12, 2);
1038               tm->tm_hour = val % 12;
1039               s.have_I = 1;
1040               break;
1041             case 'm':
1042               /* Match month using alternate numeric symbols.  */
1043               get_alt_number (1, 12, 2);
1044               tm->tm_mon = val - 1;
1045               s.have_mon = 1;
1046               s.want_xday = 1;
1047               break;
1048             case 'M':
1049               /* Match minutes using alternate numeric symbols.  */
1050               get_alt_number (0, 59, 2);
1051               tm->tm_min = val;
1052               break;
1053             case 'S':
1054               /* Match seconds using alternate numeric symbols.  */
1055               get_alt_number (0, 61, 2);
1056               tm->tm_sec = val;
1057               break;
1058             case 'U':
1059               get_alt_number (0, 53, 2);
1060               s.week_no = val;
1061               s.have_uweek = 1;
1062               break;
1063             case 'W':
1064               get_alt_number (0, 53, 2);
1065               s.week_no = val;
1066               s.have_wweek = 1;
1067               break;
1068             case 'V':
1069               get_alt_number (0, 53, 2);
1070               /* XXX This cannot determine any field in TM without
1071                  further information.  */
1072               break;
1073             case 'w':
1074               /* Match number of weekday using alternate numeric symbols.  */
1075               get_alt_number (0, 6, 1);
1076               tm->tm_wday = val;
1077               s.have_wday = 1;
1078               break;
1079             case 'y':
1080               /* Match year within century using alternate numeric symbols.  */
1081               get_alt_number (0, 99, 2);
1082               tm->tm_year = val >= 69 ? val : val + 100;
1083               s.want_xday = 1;
1084               break;
1085             default:
1086               return NULL;
1087             }
1088           break;
1089         default:
1090           return NULL;
1091         }
1092     }
1093
1094   if (statep != NULL)
1095     {
1096       /* Recursive invocation, returning success, so
1097          update parent's struct tm and state.  */
1098       *(struct __strptime_state *) statep = s;
1099       *tmp = tmb;
1100       return (char *) rp;
1101     }
1102
1103   if (s.have_I && s.is_pm)
1104     tm->tm_hour += 12;
1105
1106   if (s.century != -1)
1107     {
1108       if (s.want_century)
1109         tm->tm_year = tm->tm_year % 100 + (s.century - 19) * 100;
1110       else
1111         /* Only the century, but not the year.  Strange, but so be it.  */
1112         tm->tm_year = (s.century - 19) * 100;
1113     }
1114
1115   if (s.era_cnt != -1)
1116     {
1117       era = _nl_select_era_entry (s.era_cnt HELPER_LOCALE_ARG);
1118       if (era == NULL)
1119         return NULL;
1120       if (s.want_era)
1121         tm->tm_year = (era->start_date[0]
1122                        + ((tm->tm_year - era->offset)
1123                           * era->absolute_direction));
1124       else
1125         /* Era start year assumed.  */
1126         tm->tm_year = era->start_date[0];
1127     }
1128   else
1129     if (s.want_era)
1130       {
1131         /* No era found but we have seen an E modifier.  Rectify some
1132            values.  */
1133         if (s.want_century && s.century == -1 && tm->tm_year < 69)
1134           tm->tm_year += 100;
1135       }
1136
1137   if (s.want_xday && !s.have_wday)
1138     {
1139       if ( !(s.have_mon && s.have_mday) && s.have_yday)
1140         {
1141           /* We don't have tm_mon and/or tm_mday, compute them.  */
1142           int t_mon = 0;
1143           while (__mon_yday[__isleap(1900 + tm->tm_year)][t_mon] <= tm->tm_yday)
1144               t_mon++;
1145           if (!s.have_mon)
1146               tm->tm_mon = t_mon - 1;
1147           if (!s.have_mday)
1148               tm->tm_mday =
1149                 (tm->tm_yday
1150                  - __mon_yday[__isleap(1900 + tm->tm_year)][t_mon - 1] + 1);
1151           s.have_mon = 1;
1152           s.have_mday = 1;
1153         }
1154       /* Don't crash in day_of_the_week if tm_mon is uninitialized.  */
1155       if (s.have_mon || (unsigned) tm->tm_mon <= 11)
1156         day_of_the_week (tm);
1157     }
1158
1159   if (s.want_xday && !s.have_yday && (s.have_mon || (unsigned) tm->tm_mon <= 11))
1160     day_of_the_year (tm);
1161
1162   if ((s.have_uweek || s.have_wweek) && s.have_wday)
1163     {
1164       int save_wday = tm->tm_wday;
1165       int save_mday = tm->tm_mday;
1166       int save_mon = tm->tm_mon;
1167       int w_offset = s.have_uweek ? 0 : 1;
1168
1169       tm->tm_mday = 1;
1170       tm->tm_mon = 0;
1171       day_of_the_week (tm);
1172       if (s.have_mday)
1173         tm->tm_mday = save_mday;
1174       if (s.have_mon)
1175         tm->tm_mon = save_mon;
1176
1177       if (!s.have_yday)
1178         tm->tm_yday = ((7 - (tm->tm_wday - w_offset)) % 7
1179                        + (s.week_no - 1) * 7
1180                        + (save_wday - w_offset + 7) % 7);
1181
1182       if (!s.have_mday || !s.have_mon)
1183         {
1184           int t_mon = 0;
1185           while (__mon_yday[__isleap(1900 + tm->tm_year)][t_mon]
1186                  <= tm->tm_yday)
1187             t_mon++;
1188           if (!s.have_mon)
1189             tm->tm_mon = t_mon - 1;
1190           if (!s.have_mday)
1191               tm->tm_mday =
1192                 (tm->tm_yday
1193                  - __mon_yday[__isleap(1900 + tm->tm_year)][t_mon - 1] + 1);
1194         }
1195
1196       tm->tm_wday = save_wday;
1197     }
1198
1199   return (char *) rp;
1200 }
1201
1202
1203 char *
1204 strptime (const char *buf, const char *format, struct tm *tm LOCALE_PARAM)
1205 {
1206   return __strptime_internal (buf, format, tm, NULL LOCALE_ARG);
1207 }
1208
1209 #ifdef _LIBC
1210 weak_alias (__strptime_l, strptime_l)
1211 #endif