cmpt.c

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# endif
#endif

/* Status of lookup: do we use the locale data or the raw data?  */
enum locale_status { not, loc, raw };


#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
     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));
}

static char *
#ifdef _LIBC
internal_function
#endif
strptime_internal __P ((const char *buf, const char *format, struct tm *tm,
                        enum locale_status *decided));

static char *
#ifdef _LIBC
internal_function
#endif
strptime_internal (rp, fmt, tm, decided)
     const char *rp;
     const char *fmt;
     struct tm *tm;
     enum locale_status *decided;
{
#ifdef _NL_CURRENT
  const char *rp_backup;
#endif
  int cnt;
  size_t val;
  int have_I, is_pm;
  int century, want_century;
  int have_wday, want_xday;
  int have_yday;
  int have_mon, have_mday;

  have_I = is_pm = 0;
  century = -1;
  want_century = 0;
  have_wday = want_xday = have_yday = have_mon = have_mday = 0;

  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;
#ifndef _NL_CURRENT
      /* We need this for handling the `E' modifier.  */
    start_over:
#endif

#ifdef _NL_CURRENT
      /* Make back up of current processing pointer.  */
      rp_backup = rp;
#endif

      switch (*fmt++)
        {
        case '%':
          /* Match the `%' character itself.  */
          match_char ('%', *rp++);
          break;
        case 'a':
        case 'A':
          /* Match day of week.  */
          for (cnt = 0; cnt < 7; ++cnt)
            {
#ifdef _NL_CURRENT
              if (*decided !=raw)
                {
                  if (match_string (_NL_CURRENT (LC_TIME, DAY_1 + cnt), rp))
                    {
                      if (*decided == not
                          && strcmp (_NL_CURRENT (LC_TIME, DAY_1 + cnt),
                                     weekday_name[cnt]))
                        *decided = loc;
                      break;
                    }
                  if (match_string (_NL_CURRENT (LC_TIME, ABDAY_1 + cnt), rp))
                    {
                      if (*decided == not
                          && strcmp (_NL_CURRENT (LC_TIME, ABDAY_1 + cnt),
                                     ab_weekday_name[cnt]))
                        *decided = loc;
                      break;
                    }
                }
#endif
              if (*decided != loc
                  && (match_string (weekday_name[cnt], rp)
                      || match_string (ab_weekday_name[cnt], rp)))
                {
                  *decided = raw;
                  break;
                }
            }
          if (cnt == 7)
            /* Does not match a weekday name.  */
            return NULL;
          tm->tm_wday = cnt;
          have_wday = 1;
          break;
        case 'b':
        case 'B':
        case 'h':
          /* Match month name.  */
          for (cnt = 0; cnt < 12; ++cnt)
            {
#ifdef _NL_CURRENT
              if (*decided !=raw)
                {
                  if (match_string (_NL_CURRENT (LC_TIME, MON_1 + cnt), rp))
                    {
                      if (*decided == not
                          && strcmp (_NL_CURRENT (LC_TIME, MON_1 + cnt),
                                     month_name[cnt]))
                        *decided = loc;
                      break;
                    }
                  if (match_string (_NL_CURRENT (LC_TIME, ABMON_1 + cnt), rp))
                    {
                      if (*decided == not
                          && strcmp (_NL_CURRENT (LC_TIME, ABMON_1 + cnt),
                                     ab_month_name[cnt]))
                        *decided = loc;
                      break;
                    }
                }
#endif
              if (match_string (month_name[cnt], rp)
                  || match_string (ab_month_name[cnt], rp))
                {
                  *decided = raw;
                  break;
                }
            }
          if (cnt == 12)
            /* Does not match a month name.  */
            return NULL;
          tm->tm_mon = cnt;
          want_xday = 1;
          break;
        case 'c':
          /* Match locale's date and time format.  */
#ifdef _NL_CURRENT
          if (*decided != raw)
            {
              if (!recursive (_NL_CURRENT (LC_TIME, D_T_FMT)))
                {
                  if (*decided == loc)
                    return NULL;
                  else
                    rp = rp_backup;
                }
              else
                {
                  if (*decided == not &&
                      strcmp (_NL_CURRENT (LC_TIME, D_T_FMT), HERE_D_T_FMT))
                    *decided = loc;
                  want_xday = 1;
                  break;
                }
              *decided = raw;
            }
#endif
          if (!recursive (HERE_D_T_FMT))
            return NULL;
          want_xday = 1;
          break;
        case 'C':
          /* Match century number.  */
          get_number (0, 99, 2);
          century = val;
          want_xday = 1;
          break;
        case 'd':
        case 'e':
          /* Match day of month.  */
          get_number (1, 31, 2);
          tm->tm_mday = val;
          have_mday = 1;
          want_xday = 1;
          break;
        case 'F':
          if (!recursive ("%Y-%m-%d"))
            return NULL;
          want_xday = 1;
          break;
        case 'x':
#ifdef _NL_CURRENT
          if (*decided != raw)
            {
              if (!recursive (_NL_CURRENT (LC_TIME, D_FMT)))
                {
                  if (*decided == loc)
                    return NULL;
                  else
                    rp = rp_backup;
                }
              else
                {
                  if (*decided == not
                      && strcmp (_NL_CURRENT (LC_TIME, D_FMT), HERE_D_FMT))
                    *decided = loc;
                  want_xday = 1;
                  break;
                }
              *decided = raw;
            }
#endif
          /* Fall through.  */
        case 'D':
          /* Match standard day format.  */
          if (!recursive (HERE_D_FMT))
            return NULL;
          want_xday = 1;
          break;
        case 'k':
        case 'H':
          /* Match hour in 24-hour clock.  */
          get_number (0, 23, 2);
          tm->tm_hour = val;
          have_I = 0;
          break;
        case 'I':
          /* Match hour in 12-hour clock.  */
          get_number (1, 12, 2);
          tm->tm_hour = val % 12;
          have_I = 1;
          break;
        case 'j':
          /* Match day number of year.  */
          get_number (1, 366, 3);
          tm->tm_yday = val - 1;
          have_yday = 1;
          break;
        case 'm':
          /* Match number of month.  */
          get_number (1, 12, 2);
          tm->tm_mon = val - 1;
          have_mon = 1;
          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 (*decided != raw)
            {
              if (match_string (_NL_CURRENT (LC_TIME, AM_STR), rp))
                {
                  if (strcmp (_NL_CURRENT (LC_TIME, AM_STR), HERE_AM_STR))
                    *decided = loc;
                  break;
                }
              if (match_string (_NL_CURRENT (LC_TIME, PM_STR), rp))
                {
                  if (strcmp (_NL_CURRENT (LC_TIME, PM_STR), HERE_PM_STR))
                    *decided = loc;
                  is_pm = 1;
                  break;
                }
              *decided = raw;
            }
#endif
          if (!match_string (HERE_AM_STR, rp))
            {
              if (match_string (HERE_PM_STR, rp))
                is_pm = 1;
              else
                return NULL;
            }
          break;
        case 'r':
#ifdef _NL_CURRENT
          if (*decided != raw)
            {
              if (!recursive (_NL_CURRENT (LC_TIME, T_FMT_AMPM)))
                {
                  if (*decided == loc)
                    return NULL;
                  else
                    rp = rp_backup;
                }
              else
                {
                  if (*decided == not &&
                      strcmp (_NL_CURRENT (LC_TIME, T_FMT_AMPM),
                              HERE_T_FMT_AMPM))
                    *decided = loc;
                  break;
                }
              *decided = raw;
            }
#endif
          if (!recursive (HERE_T_FMT_AMPM))
            return NULL;
          break;
        case 'R':
          if (!recursive ("%H:%M"))