ext/Time/Piece/Piece.xs

   1 #ifdef __cplusplus
   2 #extern "C" {
   3 #endif
   4 #include "EXTERN.h"
   5 #include "perl.h"
   6 #include "XSUB.h"
   7 #include <time.h>
   8 #ifdef __cplusplus
   9 }
  10 #endif
  11
  12 /* XXX struct tm on some systems (SunOS4/BSD) contains extra (non POSIX)
  13  * fields for which we don't have Configure support yet:
  14  *   char *tm_zone;   -- abbreviation of timezone name
  15  *   long tm_gmtoff;  -- offset from GMT in seconds
  16  * To workaround core dumps from the uninitialised tm_zone we get the
  17  * system to give us a reasonable struct to copy.  This fix means that
  18  * strftime uses the tm_zone and tm_gmtoff values returned by
  19  * localtime(time()). That should give the desired result most of the
  20  * time. But probably not always!
  21  *
  22  * This is a temporary workaround to be removed once Configure
  23  * support is added and NETaa14816 is considered in full.
  24  * It does not address tzname aspects of NETaa14816.
  25  */
  26 #if !defined(HAS_GNULIBC)
  27 # ifndef STRUCT_TM_HASZONE
  28 #    define STRUCT_TM_HASZONE
  29 # else
  30 #    define USE_TM_GMTOFF
  31 # endif
  32 #endif
  33
  34 #define    DAYS_PER_YEAR    365
  35 #define    DAYS_PER_QYEAR    (4*DAYS_PER_YEAR+1)
  36 #define    DAYS_PER_CENT    (25*DAYS_PER_QYEAR-1)
  37 #define    DAYS_PER_QCENT    (4*DAYS_PER_CENT+1)
  38 #define    SECS_PER_HOUR    (60*60)
  39 #define    SECS_PER_DAY    (24*SECS_PER_HOUR)
  40 /* parentheses deliberately absent on these two, otherwise they don't work */
  41 #define    MONTH_TO_DAYS    153/5
  42 #define    DAYS_TO_MONTH    5/153
  43 /* offset to bias by March (month 4) 1st between month/mday & year finding */
  44 #define    YEAR_ADJUST    (4*MONTH_TO_DAYS+1)
  45 /* as used here, the algorithm leaves Sunday as day 1 unless we adjust it */
  46 #define    WEEKDAY_BIAS    6    /* (1+6)%7 makes Sunday 0 again */
  47
  48 #ifdef STRUCT_TM_HASZONE
  49 static void
  50 my_init_tm(struct tm *ptm)        /* see mktime, strftime and asctime    */
  51 {
  52     Time_t now;
  53     (void)time(&now);
  54     Copy(localtime(&now), ptm, 1, struct tm);
  55 }
  56
  57 #else
  58 # define my_init_tm(ptm)
  59 #endif
  60
  61 /*
  62  * my_mini_mktime - normalise struct tm values without the localtime()
  63  * semantics (and overhead) of mktime().
  64  */
  65 static void
  66 my_mini_mktime(struct tm *ptm)
  67 {
  68     int yearday;
  69     int secs;
  70     int month, mday, year, jday;
  71     int odd_cent, odd_year;
  72
  73 /*
  74  * Year/day algorithm notes:
  75  *
  76  * With a suitable offset for numeric value of the month, one can find
  77  * an offset into the year by considering months to have 30.6 (153/5) days,
  78  * using integer arithmetic (i.e., with truncation).  To avoid too much
  79  * messing about with leap days, we consider January and February to be
  80  * the 13th and 14th month of the previous year.  After that transformation,
  81  * we need the month index we use to be high by 1 from 'normal human' usage,
  82  * so the month index values we use run from 4 through 15.
  83  *
  84  * Given that, and the rules for the Gregorian calendar (leap years are those
  85  * divisible by 4 unless also divisible by 100, when they must be divisible
  86  * by 400 instead), we can simply calculate the number of days since some
  87  * arbitrary 'beginning of time' by futzing with the (adjusted) year number,
  88  * the days we derive from our month index, and adding in the day of the
  89  * month.  The value used here is not adjusted for the actual origin which
  90  * it normally would use (1 January A.D. 1), since we're not exposing it.
  91  * We're only building the value so we can turn around and get the
  92  * normalised values for the year, month, day-of-month, and day-of-year.
  93  *
  94  * For going backward, we need to bias the value we're using so that we find
  95  * the right year value.  (Basically, we don't want the contribution of
  96  * March 1st to the number to apply while deriving the year).  Having done
  97  * that, we 'count up' the contribution to the year number by accounting for
  98  * full quadracenturies (400-year periods) with their extra leap days, plus
  99  * the contribution from full centuries (to avoid counting in the lost leap
 100  * days), plus the contribution from full quad-years (to count in the normal
 101  * leap days), plus the leftover contribution from any non-leap years.
 102  * At this point, if we were working with an actual leap day, we'll have 0
 103  * days left over.  This is also true for March 1st, however.  So, we have
 104  * to special-case that result, and (earlier) keep track of the 'odd'
 105  * century and year contributions.  If we got 4 extra centuries in a qcent,
 106  * or 4 extra years in a qyear, then it's a leap day and we call it 29 Feb.
 107  * Otherwise, we add back in the earlier bias we removed (the 123 from
 108  * figuring in March 1st), find the month index (integer division by 30.6),
 109  * and the remainder is the day-of-month.  We then have to convert back to
 110  * 'real' months (including fixing January and February from being 14/15 in
 111  * the previous year to being in the proper year).  After that, to get
 112  * tm_yday, we work with the normalised year and get a new yearday value for
 113  * January 1st, which we subtract from the yearday value we had earlier,
 114  * representing the date we've re-built.  This is done from January 1
 115  * because tm_yday is 0-origin.
 116  *
 117  * Since POSIX time routines are only guaranteed to work for times since the
 118  * UNIX epoch (00:00:00 1 Jan 1970 UTC), the fact that this algorithm
 119  * applies Gregorian calendar rules even to dates before the 16th century
 120  * doesn't bother me.  Besides, you'd need cultural context for a given
 121  * date to know whether it was Julian or Gregorian calendar, and that's
 122  * outside the scope for this routine.  Since we convert back based on the
 123  * same rules we used to build the yearday, you'll only get strange results
 124  * for input which needed normalising, or for the 'odd' century years which
 125  * were leap years in the Julian calander but not in the Gregorian one.
 126  * I can live with that.
 127  *
 128  * This algorithm also fails to handle years before A.D. 1 gracefully, but
 129  * that's still outside the scope for POSIX time manipulation, so I don't
 130  * care.
 131  */
 132
 133     year = 1900 + ptm->tm_year;
 134     month = ptm->tm_mon;
 135     mday = ptm->tm_mday;
 136     /* allow given yday with no month & mday to dominate the result */
 137     if (ptm->tm_yday >= 0 && mday <= 0 && month <= 0) {
 138         month = 0;
 139         mday = 0;
 140         jday = 1 + ptm->tm_yday;
 141     }
 142     else {
 143         jday = 0;
 144     }
 145     if (month >= 2)
 146         month+=2;
 147     else
 148         month+=14, year--;
 149
 150     yearday = DAYS_PER_YEAR * year + year/4 - year/100 + year/400;
 151     yearday += month*MONTH_TO_DAYS + mday + jday;
 152     /*
 153      * Note that we don't know when leap-seconds were or will be,
 154      * so we have to trust the user if we get something which looks
 155      * like a sensible leap-second.  Wild values for seconds will
 156      * be rationalised, however.
 157      */
 158     if ((unsigned) ptm->tm_sec <= 60) {
 159         secs = 0;
 160     }
 161     else {
 162         secs = ptm->tm_sec;
 163         ptm->tm_sec = 0;
 164     }
 165     secs += 60 * ptm->tm_min;
 166     secs += SECS_PER_HOUR * ptm->tm_hour;
 167     if (secs < 0) {
 168         if (secs-(secs/SECS_PER_DAY*SECS_PER_DAY) < 0) {
 169             /* got negative remainder, but need positive time */
 170             /* back off an extra day to compensate */
 171             yearday += (secs/SECS_PER_DAY)-1;
 172             secs -= SECS_PER_DAY * (secs/SECS_PER_DAY - 1);
 173         }
 174         else {
 175             yearday += (secs/SECS_PER_DAY);
 176             secs -= SECS_PER_DAY * (secs/SECS_PER_DAY);
 177         }
 178     }
 179     else if (secs >= SECS_PER_DAY) {
 180         yearday += (secs/SECS_PER_DAY);
 181         secs %= SECS_PER_DAY;
 182     }
 183     ptm->tm_hour = secs/SECS_PER_HOUR;
 184     secs %= SECS_PER_HOUR;
 185     ptm->tm_min = secs/60;
 186     secs %= 60;
 187     ptm->tm_sec += secs;
 188     /* done with time of day effects */
 189     /*
 190      * The algorithm for yearday has (so far) left it high by 428.
 191      * To avoid mistaking a legitimate Feb 29 as Mar 1, we need to
 192      * bias it by 123 while trying to figure out what year it
 193      * really represents.  Even with this tweak, the reverse
 194      * translation fails for years before A.D. 0001.
 195      * It would still fail for Feb 29, but we catch that one below.
 196      */
 197     jday = yearday;    /* save for later fixup vis-a-vis Jan 1 */
 198     yearday -= YEAR_ADJUST;
 199     year = (yearday / DAYS_PER_QCENT) * 400;
 200     yearday %= DAYS_PER_QCENT;
 201     odd_cent = yearday / DAYS_PER_CENT;
 202     year += odd_cent * 100;
 203     yearday %= DAYS_PER_CENT;
 204     year += (yearday / DAYS_PER_QYEAR) * 4;
 205     yearday %= DAYS_PER_QYEAR;
 206     odd_year = yearday / DAYS_PER_YEAR;
 207     year += odd_year;
 208     yearday %= DAYS_PER_YEAR;
 209     if (!yearday && (odd_cent==4 || odd_year==4)) { /* catch Feb 29 */
 210         month = 1;
 211         yearday = 29;
 212     }
 213     else {
 214         yearday += YEAR_ADJUST;    /* recover March 1st crock */
 215         month = yearday*DAYS_TO_MONTH;
 216         yearday -= month*MONTH_TO_DAYS;
 217         /* recover other leap-year adjustment */
 218         if (month > 13) {
 219             month-=14;
 220             year++;
 221         }
 222         else {
 223             month-=2;
 224         }
 225     }
 226     ptm->tm_year = year - 1900;
 227     if (yearday) {
 228       ptm->tm_mday = yearday;
 229       ptm->tm_mon = month;
 230     }
 231     else {
 232       ptm->tm_mday = 31;
 233       ptm->tm_mon = month - 1;
 234     }
 235     /* re-build yearday based on Jan 1 to get tm_yday */
 236     year--;
 237     yearday = year*DAYS_PER_YEAR + year/4 - year/100 + year/400;
 238     yearday += 14*MONTH_TO_DAYS + 1;
 239     ptm->tm_yday = jday - yearday;
 240     /* fix tm_wday if not overridden by caller */
 241     ptm->tm_wday = (jday + WEEKDAY_BIAS) % 7;
 242 }
 243
 244 #if defined(WIN32) /* No strptime on Win32 */
 245 #define strncasecmp(x,y,n) strnicmp(x,y,n)
 246 #define alloca _alloca
 247 #include <time.h>
 248 #include <ctype.h>
 249 #include <string.h>
 250 #ifdef _THREAD_SAFE
 251 #include <pthread.h>
 252 #include "pthread_private.h"
 253 #endif /* _THREAD_SAFE */
 254
 255 static char * _strptime(const char *, const char *, struct tm *);
 256
 257 #ifdef _THREAD_SAFE
 258 static struct pthread_mutex     _gotgmt_mutexd = PTHREAD_MUTEX_STATIC_INITIALIZER;
 259 static pthread_mutex_t          gotgmt_mutex   = &_gotgmt_mutexd;
 260 #endif
 261 static int got_GMT;
 262
 263 #define asizeof(a)      (sizeof (a) / sizeof ((a)[0]))
 264
 265 struct lc_time_T {
 266     const char *    mon[12];
 267     const char *    month[12];
 268     const char *    wday[7];
 269     const char *    weekday[7];
 270     const char *    X_fmt;
 271     const char *    x_fmt;
 272     const char *    c_fmt;
 273     const char *    am;
 274     const char *    pm;
 275     const char *    date_fmt;
 276     const char *    alt_month[12];
 277     const char *    Ef_fmt;
 278     const char *    EF_fmt;
 279 };
 280
 281 struct lc_time_T _time_localebuf;
 282 int _time_using_locale;
 283
 284 const struct lc_time_T  _C_time_locale = {
 285         {
 286                 "Jan", "Feb", "Mar", "Apr", "May", "Jun",
 287                 "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
 288         }, {
 289                 "January", "February", "March", "April", "May", "June",
 290                 "July", "August", "September", "October", "November", "December"
 291         }, {
 292                 "Sun", "Mon", "Tue", "Wed",
 293                 "Thu", "Fri", "Sat"
 294         }, {
 295                 "Sunday", "Monday", "Tuesday", "Wednesday",
 296                 "Thursday", "Friday", "Saturday"
 297         },
 298
 299         /* X_fmt */
 300         "%H:%M:%S",
 301
 302         /*
 303         ** x_fmt
 304         ** Since the C language standard calls for
 305         ** "date, using locale's date format," anything goes.
 306         ** Using just numbers (as here) makes Quakers happier;
 307         ** it's also compatible with SVR4.
 308         */
 309         "%m/%d/%y",
 310
 311         /*
 312         ** c_fmt (ctime-compatible)
 313         ** Not used, just compatibility placeholder.
 314         */
 315         NULL,
 316
 317         /* am */
 318         "AM",
 319
 320         /* pm */
 321         "PM",
 322
 323         /* date_fmt */
 324         "%a %Ef %X %Z %Y",
 325
 326         {
 327                 "January", "February", "March", "April", "May", "June",
 328                 "July", "August", "September", "October", "November", "December"
 329         },
 330
 331         /* Ef_fmt
 332         ** To determine short months / day order
 333         */
 334         "%b %e",
 335
 336         /* EF_fmt
 337         ** To determine long months / day order
 338         */
 339         "%B %e"
 340 };
 341
 342 #define Locale (&_C_time_locale)
 343
 344 static char *
 345 _strptime(const char *buf, const char *fmt, struct tm *tm)
 346 {
 347         char c;
 348         const char *ptr;
 349         int i,
 350                 len;
 351         int Ealternative, Oalternative;
 352
 353         ptr = fmt;
 354         while (*ptr != 0) {
 355                 if (*buf == 0)
 356                         break;
 357
 358                 c = *ptr++;
 359
 360                 if (c != '%') {
 361                         if (isspace((unsigned char)c))
 362                                 while (*buf != 0 && isspace((unsigned char)*buf))
 363                                         buf++;
 364                         else if (c != *buf++)
 365                                 return 0;
 366                         continue;
 367                 }
 368
 369                 Ealternative = 0;
 370                 Oalternative = 0;
 371 label:
 372                 c = *ptr++;
 373                 switch (c) {
 374                 case 0:
 375                 case '%':
 376                         if (*buf++ != '%')
 377                                 return 0;
 378                         break;
 379
 380                 case '+':
 381                         buf = _strptime(buf, Locale->date_fmt, tm);
 382                         if (buf == 0)
 383                                 return 0;
 384                         break;
 385
 386                 case 'C':
 387                         if (!isdigit((unsigned char)*buf))
 388                                 return 0;
 389
 390                         /* XXX This will break for 3-digit centuries. */
 391                         len = 2;
 392                         for (i = 0; len && *buf != 0 && isdigit((unsigned char)*buf); buf++) {
 393                                 i *= 10;
 394                                 i += *buf - '0';
 395                                 len--;
 396                         }
 397                         if (i < 19)
 398                                 return 0;
 399
 400                         tm->tm_year = i * 100 - 1900;
 401                         break;
 402
 403                 case 'c':
 404                         /* NOTE: c_fmt is intentionally ignored */
 405                         buf = _strptime(buf, "%a %Ef %T %Y", tm);
 406                         if (buf == 0)
 407                                 return 0;
 408                         break;
 409
 410                 case 'D':
 411                         buf = _strptime(buf, "%m/%d/%y", tm);
 412                         if (buf == 0)
 413                                 return 0;
 414                         break;
 415
 416                 case 'E':
 417                         if (Ealternative || Oalternative)
 418                                 break;
 419                         Ealternative++;
 420                         goto label;
 421
 422                 case 'O':
 423                         if (Ealternative || Oalternative)
 424                                 break;
 425                         Oalternative++;
 426                         goto label;
 427
 428                 case 'F':
 429                 case 'f':
 430                         if (!Ealternative)
 431                                 break;
 432                         buf = _strptime(buf, (c == 'f') ? Locale->Ef_fmt : Locale->EF_fmt, tm);
 433                         if (buf == 0)
 434                                 return 0;
 435                         break;
 436
 437                 case 'R':
 438                         buf = _strptime(buf, "%H:%M", tm);
 439                         if (buf == 0)
 440                                 return 0;
 441                         break;
 442
 443                 case 'r':
 444                         buf = _strptime(buf, "%I:%M:%S %p", tm);
 445                         if (buf == 0)
 446                                 return 0;
 447                         break;
 448
 449                 case 'T':
 450                         buf = _strptime(buf, "%H:%M:%S", tm);
 451                         if (buf == 0)
 452                                 return 0;
 453                         break;
 454
 455                 case 'X':
 456                         buf = _strptime(buf, Locale->X_fmt, tm);
 457                         if (buf == 0)
 458                                 return 0;
 459                         break;
 460
 461                 case 'x':
 462                         buf = _strptime(buf, Locale->x_fmt, tm);
 463                         if (buf == 0)
 464                                 return 0;
 465                         break;
 466
 467                 case 'j':
 468                         if (!isdigit((unsigned char)*buf))
 469                                 return 0;
 470
 471                         len = 3;
 472                         for (i = 0; len && *buf != 0 && isdigit((unsigned char)*buf); buf++) {
 473                                 i *= 10;
 474                                 i += *buf - '0';
 475                                 len--;
 476                         }
 477                         if (i < 1 || i > 366)
 478                                 return 0;
 479
 480                         tm->tm_yday = i - 1;
 481                         break;
 482
 483                 case 'M':
 484                 case 'S':
 485                         if (*buf == 0 || isspace((unsigned char)*buf))
 486                                 break;
 487
 488                         if (!isdigit((unsigned char)*buf))
 489                                 return 0;
 490
 491                         len = 2;
 492                         for (i = 0; len && *buf != 0 && isdigit((unsigned char)*buf); buf++) {
 493                                 i *= 10;
 494                                 i += *buf - '0';
 495                                 len--;
 496                         }
 497
 498                         if (c == 'M') {
 499                                 if (i > 59)
 500                                         return 0;
 501                                 tm->tm_min = i;
 502                         } else {
 503                                 if (i > 60)
 504                                         return 0;
 505                                 tm->tm_sec = i;
 506                         }
 507
 508                         if (*buf != 0 && isspace((unsigned char)*buf))
 509                                 while (*ptr != 0 && !isspace((unsigned char)*ptr))
 510                                         ptr++;
 511                         break;
 512
 513                 case 'H':
 514                 case 'I':
 515                 case 'k':
 516                 case 'l':
 517                         /*
 518                          * Of these, %l is the only specifier explicitly
 519                          * documented as not being zero-padded.  However,
 520                          * there is no harm in allowing zero-padding.
 521                          *
 522                          * XXX The %l specifier may gobble one too many
 523                          * digits if used incorrectly.
 524                          */
 525                         if (!isdigit((unsigned char)*buf))
 526                                 return 0;
 527
 528                         len = 2;
 529                         for (i = 0; len && *buf != 0 && isdigit((unsigned char)*buf); buf++) {
 530                                 i *= 10;
 531                                 i += *buf - '0';
 532                                 len--;
 533                         }
 534                         if (c == 'H' || c == 'k') {
 535                                 if (i > 23)
 536                                         return 0;
 537                         } else if (i > 12)
 538                                 return 0;
 539
 540                         tm->tm_hour = i;
 541
 542                         if (*buf != 0 && isspace((unsigned char)*buf))
 543                                 while (*ptr != 0 && !isspace((unsigned char)*ptr))
 544                                         ptr++;
 545                         break;
 546
 547                 case 'p':
 548                         /*
 549                          * XXX This is bogus if parsed before hour-related
 550                          * specifiers.
 551                          */
 552                         len = strlen(Locale->am);
 553                         if (strncasecmp(buf, Locale->am, len) == 0) {
 554                                 if (tm->tm_hour > 12)
 555                                         return 0;
 556                                 if (tm->tm_hour == 12)
 557                                         tm->tm_hour = 0;
 558                                 buf += len;
 559                                 break;
 560                         }
 561
 562                         len = strlen(Locale->pm);
 563                         if (strncasecmp(buf, Locale->pm, len) == 0) {
 564                                 if (tm->tm_hour > 12)
 565                                         return 0;
 566                                 if (tm->tm_hour != 12)
 567                                         tm->tm_hour += 12;
 568                                 buf += len;
 569                                 break;
 570                         }
 571
 572                         return 0;
 573
 574                 case 'A':
 575                 case 'a':
 576                         for (i = 0; i < asizeof(Locale->weekday); i++) {
 577                                 if (c == 'A') {
 578                                         len = strlen(Locale->weekday[i]);
 579                                         if (strncasecmp(buf,
 580                                                         Locale->weekday[i],
 581                                                         len) == 0)
 582                                                 break;
 583                                 } else {
 584                                         len = strlen(Locale->wday[i]);
 585                                         if (strncasecmp(buf,
 586                                                         Locale->wday[i],
 587                                                         len) == 0)
 588                                                 break;
 589                                 }
 590                         }
 591                         if (i == asizeof(Locale->weekday))
 592                                 return 0;
 593
 594                         tm->tm_wday = i;
 595                         buf += len;
 596                         break;
 597
 598                 case 'U':
 599                 case 'W':
 600                         /*
 601                          * XXX This is bogus, as we can not assume any valid
 602                          * information present in the tm structure at this
 603                          * point to calculate a real value, so just check the
 604                          * range for now.
 605                          */
 606                         if (!isdigit((unsigned char)*buf))
 607                                 return 0;
 608
 609                         len = 2;
 610                         for (i = 0; len && *buf != 0 && isdigit((unsigned char)*buf); buf++) {
 611                                 i *= 10;
 612                                 i += *buf - '0';
 613                                 len--;
 614                         }
 615                         if (i > 53)
 616                                 return 0;
 617
 618                         if (*buf != 0 && isspace((unsigned char)*buf))
 619                                 while (*ptr != 0 && !isspace((unsigned char)*ptr))
 620                                         ptr++;
 621                         break;
 622
 623                 case 'w':
 624                         if (!isdigit((unsigned char)*buf))
 625                                 return 0;
 626
 627                         i = *buf - '0';
 628                         if (i > 6)
 629                                 return 0;
 630
 631                         tm->tm_wday = i;
 632
 633                         if (*buf != 0 && isspace((unsigned char)*buf))
 634                                 while (*ptr != 0 && !isspace((unsigned char)*ptr))
 635                                         ptr++;
 636                         break;
 637
 638                 case 'd':
 639                 case 'e':
 640                         /*
 641                          * The %e specifier is explicitly documented as not
 642                          * being zero-padded but there is no harm in allowing
 643                          * such padding.
 644                          *
 645                          * XXX The %e specifier may gobble one too many
 646                          * digits if used incorrectly.
 647                          */
 648                         if (!isdigit((unsigned char)*buf))
 649                                 return 0;
 650
 651                         len = 2;
 652                         for (i = 0; len && *buf != 0 && isdigit((unsigned char)*buf); buf++) {
 653                                 i *= 10;
 654                                 i += *buf - '0';
 655                                 len--;
 656                         }
 657                         if (i > 31)
 658                                 return 0;
 659
 660                         tm->tm_mday = i;
 661
 662                         if (*buf != 0 && isspace((unsigned char)*buf))
 663                                 while (*ptr != 0 && !isspace((unsigned char)*ptr))
 664                                         ptr++;
 665                         break;
 666
 667                 case 'B':
 668                 case 'b':
 669                 case 'h':
 670                         for (i = 0; i < asizeof(Locale->month); i++) {
 671                                 if (Oalternative) {
 672                                         if (c == 'B') {
 673                                                 len = strlen(Locale->alt_month[i]);
 674                                                 if (strncasecmp(buf,
 675                                                                 Locale->alt_month[i],
 676                                                                 len) == 0)
 677                                                         break;
 678                                         }
 679                                 } else {
 680                                         if (c == 'B') {
 681                                                 len = strlen(Locale->month[i]);
 682                                                 if (strncasecmp(buf,
 683                                                                 Locale->month[i],
 684                                                                 len) == 0)
 685                                                         break;
 686                                         } else {
 687                                                 len = strlen(Locale->mon[i]);
 688                                                 if (strncasecmp(buf,
 689                                                                 Locale->mon[i],
 690                                                                 len) == 0)
 691                                                         break;
 692                                         }
 693                                 }
 694                         }
 695                         if (i == asizeof(Locale->month))
 696                                 return 0;
 697
 698                         tm->tm_mon = i;
 699                         buf += len;
 700                         break;
 701
 702                 case 'm':
 703                         if (!isdigit((unsigned char)*buf))
 704                                 return 0;
 705
 706                         len = 2;
 707                         for (i = 0; len && *buf != 0 && isdigit((unsigned char)*buf); buf++) {
 708                                 i *= 10;
 709                                 i += *buf - '0';
 710                                 len--;
 711                         }
 712                         if (i < 1 || i > 12)
 713                                 return 0;
 714
 715                         tm->tm_mon = i - 1;
 716
 717                         if (*buf != 0 && isspace((unsigned char)*buf))
 718                                 while (*ptr != 0 && !isspace((unsigned char)*ptr))
 719                                         ptr++;
 720                         break;
 721
 722                 case 'Y':
 723                 case 'y':
 724                         if (*buf == 0 || isspace((unsigned char)*buf))
 725                                 break;
 726
 727                         if (!isdigit((unsigned char)*buf))
 728                                 return 0;
 729
 730                         len = (c == 'Y') ? 4 : 2;
 731                         for (i = 0; len && *buf != 0 && isdigit((unsigned char)*buf); buf++) {
 732                                 i *= 10;
 733                                 i += *buf - '0';
 734                                 len--;
 735                         }
 736                         if (c == 'Y')
 737                                 i -= 1900;
 738                         if (c == 'y' && i < 69)
 739                                 i += 100;
 740                         if (i < 0)
 741                                 return 0;
 742
 743                         tm->tm_year = i;
 744
 745                         if (*buf != 0 && isspace((unsigned char)*buf))
 746                                 while (*ptr != 0 && !isspace((unsigned char)*ptr))
 747                                         ptr++;
 748                         break;
 749
 750                 case 'Z':
 751                         {
 752                         const char *cp;
 753                         char *zonestr;
 754
 755                         for (cp = buf; *cp && isupper((unsigned char)*cp); ++cp)
 756                             {/*empty*/}
 757                         if (cp - buf) {
 758                                 zonestr = alloca(cp - buf + 1);
 759                                 strncpy(zonestr, buf, cp - buf);
 760                                 zonestr[cp - buf] = '\0';
 761                                 tzset();
 762                                 if (0 == strcmp(zonestr, "GMT")) {
 763                                     got_GMT = 1;
 764                                 } else {
 765                                     return 0;
 766                                 }
 767                                 buf += cp - buf;
 768                         }
 769                         }
 770                         break;
 771                 }
 772         }
 773         return (char *)buf;
 774 }
 775
 776
 777 char *
 778 strptime(const char *buf, const char *fmt, struct tm *tm)
 779 {
 780         char *ret;
 781
 782 #ifdef _THREAD_SAFE
 783 pthread_mutex_lock(&gotgmt_mutex);
 784 #endif
 785
 786         got_GMT = 0;
 787         ret = _strptime(buf, fmt, tm);
 788
 789 #ifdef _THREAD_SAFE
 790         pthread_mutex_unlock(&gotgmt_mutex);
 791 #endif
 792
 793         return ret;
 794 }
 795
 796 #endif /* Mac OS X */
 797
 798 MODULE = Time::Piece     PACKAGE = Time::Piece
 799
 800 PROTOTYPES: ENABLE
 801
 802 char *
 803 _strftime(fmt, sec, min, hour, mday, mon, year, wday = -1, yday = -1, isdst = -1)
 804     char *        fmt
 805     int        sec
 806     int        min
 807     int        hour
 808     int        mday
 809     int        mon
 810     int        year
 811     int        wday
 812     int        yday
 813     int        isdst
 814     CODE:
 815     {
 816         char tmpbuf[128];
 817         struct tm mytm;
 818         int len;
 819         memset(&mytm, 0, sizeof(mytm));
 820         my_init_tm(&mytm);    /* XXX workaround - see my_init_tm() above */
 821         mytm.tm_sec = sec;
 822         mytm.tm_min = min;
 823         mytm.tm_hour = hour;
 824         mytm.tm_mday = mday;
 825         mytm.tm_mon = mon;
 826         mytm.tm_year = year;
 827         mytm.tm_wday = wday;
 828         mytm.tm_yday = yday;
 829         mytm.tm_isdst = isdst;
 830         my_mini_mktime(&mytm);
 831         len = strftime(tmpbuf, sizeof tmpbuf, fmt, &mytm);
 832         /*
 833         ** The following is needed to handle to the situation where
 834         ** tmpbuf overflows.  Basically we want to allocate a buffer
 835         ** and try repeatedly.  The reason why it is so complicated
 836         ** is that getting a return value of 0 from strftime can indicate
 837         ** one of the following:
 838         ** 1. buffer overflowed,
 839         ** 2. illegal conversion specifier, or
 840         ** 3. the format string specifies nothing to be returned(not
 841         **      an error).  This could be because format is an empty string
 842         **    or it specifies %p that yields an empty string in some locale.
 843         ** If there is a better way to make it portable, go ahead by
 844         ** all means.
 845         */
 846         if ((len > 0 && len < sizeof(tmpbuf)) || (len == 0 && *fmt == '\0'))
 847         ST(0) = sv_2mortal(newSVpv(tmpbuf, len));
 848         else {
 849         /* Possibly buf overflowed - try again with a bigger buf */
 850         int     fmtlen = strlen(fmt);
 851         int    bufsize = fmtlen + sizeof(tmpbuf);
 852         char*     buf;
 853         int    buflen;
 854
 855         New(0, buf, bufsize, char);
 856         while (buf) {
 857             buflen = strftime(buf, bufsize, fmt, &mytm);
 858             if (buflen > 0 && buflen < bufsize)
 859             break;
 860             /* heuristic to prevent out-of-memory errors */
 861             if (bufsize > 100*fmtlen) {
 862             Safefree(buf);
 863             buf = NULL;
 864             break;
 865             }
 866             bufsize *= 2;
 867             Renew(buf, bufsize, char);
 868         }
 869         if (buf) {
 870             ST(0) = sv_2mortal(newSVpv(buf, buflen));
 871             Safefree(buf);
 872         }
 873         else
 874             ST(0) = sv_2mortal(newSVpv(tmpbuf, len));
 875         }
 876     }
 877
 878 void
 879 _tzset()
 880   PPCODE:
 881     tzset();
 882
 883
 884 void
 885 _strptime ( string, format )
 886         char * string
 887         char * format
 888   PREINIT:
 889        char tmpbuf[128];
 890        struct tm mytm;
 891        time_t t;
 892        char * remainder;
 893        int len;
 894        int tzdiff;
 895   PPCODE:
 896        t = 0;
 897        mytm = *gmtime(&t);
 898
 899        remainder = (char *)strptime(string, format, &mytm);
 900
 901        if (remainder == NULL) {
 902           croak("Error parsing time");
 903        }
 904
 905        if (*remainder != '\0') {
 906            warn("garbage at end of string in strptime: %s", remainder);
 907        }
 908
 909        my_mini_mktime(&mytm);
 910
 911   /* warn("tm: %d-%d-%d %d:%d:%d\n", mytm.tm_year, mytm.tm_mon, mytm.tm_mday, mytm.tm_hour, mytm.tm_min, mytm.tm_sec); */
 912
 913        EXTEND(SP, 11);
 914        PUSHs(sv_2mortal(newSViv(mytm.tm_sec)));
 915        PUSHs(sv_2mortal(newSViv(mytm.tm_min)));
 916        PUSHs(sv_2mortal(newSViv(mytm.tm_hour)));
 917        PUSHs(sv_2mortal(newSViv(mytm.tm_mday)));
 918        PUSHs(sv_2mortal(newSViv(mytm.tm_mon)));
 919        PUSHs(sv_2mortal(newSViv(mytm.tm_year)));
 920        PUSHs(sv_2mortal(newSViv(mytm.tm_wday)));
 921        PUSHs(sv_2mortal(newSViv(mytm.tm_yday)));
 922        /* isdst */
 923        PUSHs(sv_2mortal(newSViv(0)));
 924        /* epoch */
 925        PUSHs(sv_2mortal(newSViv(0)));
 926        /* islocal */
 927        PUSHs(sv_2mortal(newSViv(0)));