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      1 /* Portions are Copyright (C) 2007 Google Inc */
      2 /* ***** BEGIN LICENSE BLOCK *****
      3  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
      4  *
      5  * The contents of this file are subject to the Mozilla Public License Version
      6  * 1.1 (the "License"); you may not use this file except in compliance with
      7  * the License. You may obtain a copy of the License at
      8  * http://www.mozilla.org/MPL/
      9  *
     10  * Software distributed under the License is distributed on an "AS IS" basis,
     11  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
     12  * for the specific language governing rights and limitations under the
     13  * License.
     14  *
     15  * The Original Code is the Netscape Portable Runtime (NSPR).
     16  *
     17  * The Initial Developer of the Original Code is
     18  * Netscape Communications Corporation.
     19  * Portions created by the Initial Developer are Copyright (C) 1998-2000
     20  * the Initial Developer. All Rights Reserved.
     21  *
     22  * Contributor(s):
     23  *
     24  * Alternatively, the contents of this file may be used under the terms of
     25  * either the GNU General Public License Version 2 or later (the "GPL"), or
     26  * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
     27  * in which case the provisions of the GPL or the LGPL are applicable instead
     28  * of those above. If you wish to allow use of your version of this file only
     29  * under the terms of either the GPL or the LGPL, and not to allow others to
     30  * use your version of this file under the terms of the MPL, indicate your
     31  * decision by deleting the provisions above and replace them with the notice
     32  * and other provisions required by the GPL or the LGPL. If you do not delete
     33  * the provisions above, a recipient may use your version of this file under
     34  * the terms of any one of the MPL, the GPL or the LGPL.
     35  *
     36  * ***** END LICENSE BLOCK ***** */
     37 
     38 /*
     39  * prtime.cc --
     40  * NOTE: The original nspr file name is prtime.c
     41  *
     42  *     NSPR date and time functions
     43  *
     44  * CVS revision 3.37
     45  */
     46 
     47 /*
     48  * The following functions were copied from the NSPR prtime.c file.
     49  * PR_ParseTimeString
     50  *   We inlined the new PR_ParseTimeStringToExplodedTime function to avoid
     51  *   copying PR_ExplodeTime and PR_LocalTimeParameters.  (The PR_ExplodeTime
     52  *   and PR_ImplodeTime calls cancel each other out.)
     53  * PR_NormalizeTime
     54  * PR_GMTParameters
     55  * PR_ImplodeTime
     56  *   This was modified to use the Win32 SYSTEMTIME/FILETIME structures
     57  *   and the timezone offsets are applied to the FILETIME structure.
     58  * All types and macros are defined in the base/third_party/prtime.h file.
     59  * These have been copied from the following nspr files. We have only copied
     60  * over the types we need.
     61  * 1. prtime.h
     62  * 2. prtypes.h
     63  * 3. prlong.h
     64  */
     65 
     66 #include "base/third_party/nspr/prtime.h"
     67 #include "build/build_config.h"
     68 
     69 #if defined(OS_WIN)
     70 #include <windows.h>
     71 #elif defined(OS_MACOSX)
     72 #include <CoreFoundation/CoreFoundation.h>
     73 #endif
     74 #include <errno.h>  /* for EINVAL */
     75 #include <time.h>
     76 
     77 /* Implements the Unix localtime_r() function for windows */
     78 #if defined(OS_WIN)
     79 static void localtime_r(const time_t* secs, struct tm* time) {
     80   (void) localtime_s(time, secs);
     81 }
     82 #endif
     83 
     84 /*
     85  *------------------------------------------------------------------------
     86  *
     87  * PR_ImplodeTime --
     88  *
     89  *     Cf. time_t mktime(struct tm *tp)
     90  *     Note that 1 year has < 2^25 seconds.  So an PRInt32 is large enough.
     91  *
     92  *------------------------------------------------------------------------
     93  */
     94 PRTime
     95 PR_ImplodeTime(const PRExplodedTime *exploded)
     96 {
     97     // This is important, we want to make sure multiplications are
     98     // done with the correct precision.
     99     static const PRTime kSecondsToMicroseconds = static_cast<PRTime>(1000000);
    100 #if defined(OS_WIN)
    101    // Create the system struct representing our exploded time.
    102     SYSTEMTIME st = {0};
    103     FILETIME ft = {0};
    104     ULARGE_INTEGER uli = {0};
    105 
    106     st.wYear = exploded->tm_year;
    107     st.wMonth = exploded->tm_month + 1;
    108     st.wDayOfWeek = exploded->tm_wday;
    109     st.wDay = exploded->tm_mday;
    110     st.wHour = exploded->tm_hour;
    111     st.wMinute = exploded->tm_min;
    112     st.wSecond = exploded->tm_sec;
    113     st.wMilliseconds = exploded->tm_usec/1000;
    114      // Convert to FILETIME.
    115     if (!SystemTimeToFileTime(&st, &ft)) {
    116       NOTREACHED() << "Unable to convert time";
    117       return 0;
    118     }
    119     // Apply offsets.
    120     uli.LowPart = ft.dwLowDateTime;
    121     uli.HighPart = ft.dwHighDateTime;
    122     // Convert from Windows epoch to NSPR epoch, and 100-nanoseconds units
    123     // to microsecond units.
    124     PRTime result =
    125         static_cast<PRTime>((uli.QuadPart / 10) - 11644473600000000i64);
    126     // Adjust for time zone and dst.  Convert from seconds to microseconds.
    127     result -= (exploded->tm_params.tp_gmt_offset +
    128                exploded->tm_params.tp_dst_offset) * kSecondsToMicroseconds;
    129     return result;
    130 #elif defined(OS_MACOSX)
    131     // Create the system struct representing our exploded time.
    132     CFGregorianDate gregorian_date;
    133     gregorian_date.year = exploded->tm_year;
    134     gregorian_date.month = exploded->tm_month + 1;
    135     gregorian_date.day = exploded->tm_mday;
    136     gregorian_date.hour = exploded->tm_hour;
    137     gregorian_date.minute = exploded->tm_min;
    138     gregorian_date.second = exploded->tm_sec;
    139 
    140     // Compute |absolute_time| in seconds, correct for gmt and dst
    141     // (note the combined offset will be negative when we need to add it), then
    142     // convert to microseconds which is what PRTime expects.
    143     CFAbsoluteTime absolute_time =
    144         CFGregorianDateGetAbsoluteTime(gregorian_date, NULL);
    145     PRTime result = static_cast<PRTime>(absolute_time);
    146     result -= exploded->tm_params.tp_gmt_offset +
    147               exploded->tm_params.tp_dst_offset;
    148     result += kCFAbsoluteTimeIntervalSince1970;  // PRTime epoch is 1970
    149     result *= kSecondsToMicroseconds;
    150     result += exploded->tm_usec;
    151     return result;
    152 #elif defined(OS_POSIX)
    153     struct tm exp_tm = {0};
    154     exp_tm.tm_sec  = exploded->tm_sec;
    155     exp_tm.tm_min  = exploded->tm_min;
    156     exp_tm.tm_hour = exploded->tm_hour;
    157     exp_tm.tm_mday = exploded->tm_mday;
    158     exp_tm.tm_mon  = exploded->tm_month;
    159     exp_tm.tm_year = exploded->tm_year - 1900;
    160 
    161     time_t absolute_time = timegm(&exp_tm);
    162 
    163     // If timegm returned -1.  Since we don't pass it a time zone, the only
    164     // valid case of returning -1 is 1 second before Epoch (Dec 31, 1969).
    165     if (absolute_time == -1 &&
    166         !(exploded->tm_year == 1969 && exploded->tm_month == 11 &&
    167         exploded->tm_mday == 31 && exploded->tm_hour == 23 &&
    168         exploded->tm_min == 59 && exploded->tm_sec == 59)) {
    169       // If we get here, time_t must be 32 bits.
    170       // Date was possibly too far in the future and would overflow.  Return
    171       // the most future date possible (year 2038).
    172       if (exploded->tm_year >= 1970)
    173         return INT_MAX * kSecondsToMicroseconds;
    174       // Date was possibly too far in the past and would underflow.  Return
    175       // the most past date possible (year 1901).
    176       return INT_MIN * kSecondsToMicroseconds;
    177     }
    178 
    179     PRTime result = static_cast<PRTime>(absolute_time);
    180     result -= exploded->tm_params.tp_gmt_offset +
    181               exploded->tm_params.tp_dst_offset;
    182     result *= kSecondsToMicroseconds;
    183     result += exploded->tm_usec;
    184     return result;
    185 #else
    186 #error No PR_ImplodeTime implemented on your platform.
    187 #endif
    188 }
    189 
    190 /*
    191  * The COUNT_LEAPS macro counts the number of leap years passed by
    192  * till the start of the given year Y.  At the start of the year 4
    193  * A.D. the number of leap years passed by is 0, while at the start of
    194  * the year 5 A.D. this count is 1. The number of years divisible by
    195  * 100 but not divisible by 400 (the non-leap years) is deducted from
    196  * the count to get the correct number of leap years.
    197  *
    198  * The COUNT_DAYS macro counts the number of days since 01/01/01 till the
    199  * start of the given year Y. The number of days at the start of the year
    200  * 1 is 0 while the number of days at the start of the year 2 is 365
    201  * (which is ((2)-1) * 365) and so on. The reference point is 01/01/01
    202  * midnight 00:00:00.
    203  */
    204 
    205 #define COUNT_LEAPS(Y)   ( ((Y)-1)/4 - ((Y)-1)/100 + ((Y)-1)/400 )
    206 #define COUNT_DAYS(Y)  ( ((Y)-1)*365 + COUNT_LEAPS(Y) )
    207 #define DAYS_BETWEEN_YEARS(A, B)  (COUNT_DAYS(B) - COUNT_DAYS(A))
    208 
    209 /*
    210  * Static variables used by functions in this file
    211  */
    212 
    213 /*
    214  * The following array contains the day of year for the last day of
    215  * each month, where index 1 is January, and day 0 is January 1.
    216  */
    217 
    218 static const int lastDayOfMonth[2][13] = {
    219     {-1, 30, 58, 89, 119, 150, 180, 211, 242, 272, 303, 333, 364},
    220     {-1, 30, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365}
    221 };
    222 
    223 /*
    224  * The number of days in a month
    225  */
    226 
    227 static const PRInt8 nDays[2][12] = {
    228     {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31},
    229     {31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}
    230 };
    231 
    232 /*
    233  *-------------------------------------------------------------------------
    234  *
    235  * IsLeapYear --
    236  *
    237  *     Returns 1 if the year is a leap year, 0 otherwise.
    238  *
    239  *-------------------------------------------------------------------------
    240  */
    241 
    242 static int IsLeapYear(PRInt16 year)
    243 {
    244     if ((year % 4 == 0 && year % 100 != 0) || year % 400 == 0)
    245         return 1;
    246     else
    247         return 0;
    248 }
    249 
    250 /*
    251  * 'secOffset' should be less than 86400 (i.e., a day).
    252  * 'time' should point to a normalized PRExplodedTime.
    253  */
    254 
    255 static void
    256 ApplySecOffset(PRExplodedTime *time, PRInt32 secOffset)
    257 {
    258     time->tm_sec += secOffset;
    259 
    260     /* Note that in this implementation we do not count leap seconds */
    261     if (time->tm_sec < 0 || time->tm_sec >= 60) {
    262         time->tm_min += time->tm_sec / 60;
    263         time->tm_sec %= 60;
    264         if (time->tm_sec < 0) {
    265             time->tm_sec += 60;
    266             time->tm_min--;
    267         }
    268     }
    269 
    270     if (time->tm_min < 0 || time->tm_min >= 60) {
    271         time->tm_hour += time->tm_min / 60;
    272         time->tm_min %= 60;
    273         if (time->tm_min < 0) {
    274             time->tm_min += 60;
    275             time->tm_hour--;
    276         }
    277     }
    278 
    279     if (time->tm_hour < 0) {
    280         /* Decrement mday, yday, and wday */
    281         time->tm_hour += 24;
    282         time->tm_mday--;
    283         time->tm_yday--;
    284         if (time->tm_mday < 1) {
    285             time->tm_month--;
    286             if (time->tm_month < 0) {
    287                 time->tm_month = 11;
    288                 time->tm_year--;
    289                 if (IsLeapYear(time->tm_year))
    290                     time->tm_yday = 365;
    291                 else
    292                     time->tm_yday = 364;
    293             }
    294             time->tm_mday = nDays[IsLeapYear(time->tm_year)][time->tm_month];
    295         }
    296         time->tm_wday--;
    297         if (time->tm_wday < 0)
    298             time->tm_wday = 6;
    299     } else if (time->tm_hour > 23) {
    300         /* Increment mday, yday, and wday */
    301         time->tm_hour -= 24;
    302         time->tm_mday++;
    303         time->tm_yday++;
    304         if (time->tm_mday >
    305                 nDays[IsLeapYear(time->tm_year)][time->tm_month]) {
    306             time->tm_mday = 1;
    307             time->tm_month++;
    308             if (time->tm_month > 11) {
    309                 time->tm_month = 0;
    310                 time->tm_year++;
    311                 time->tm_yday = 0;
    312             }
    313         }
    314         time->tm_wday++;
    315         if (time->tm_wday > 6)
    316             time->tm_wday = 0;
    317     }
    318 }
    319 
    320 void
    321 PR_NormalizeTime(PRExplodedTime *time, PRTimeParamFn params)
    322 {
    323     int daysInMonth;
    324     PRInt32 numDays;
    325 
    326     /* Get back to GMT */
    327     time->tm_sec -= time->tm_params.tp_gmt_offset
    328             + time->tm_params.tp_dst_offset;
    329     time->tm_params.tp_gmt_offset = 0;
    330     time->tm_params.tp_dst_offset = 0;
    331 
    332     /* Now normalize GMT */
    333 
    334     if (time->tm_usec < 0 || time->tm_usec >= 1000000) {
    335         time->tm_sec +=  time->tm_usec / 1000000;
    336         time->tm_usec %= 1000000;
    337         if (time->tm_usec < 0) {
    338             time->tm_usec += 1000000;
    339             time->tm_sec--;
    340         }
    341     }
    342 
    343     /* Note that we do not count leap seconds in this implementation */
    344     if (time->tm_sec < 0 || time->tm_sec >= 60) {
    345         time->tm_min += time->tm_sec / 60;
    346         time->tm_sec %= 60;
    347         if (time->tm_sec < 0) {
    348             time->tm_sec += 60;
    349             time->tm_min--;
    350         }
    351     }
    352 
    353     if (time->tm_min < 0 || time->tm_min >= 60) {
    354         time->tm_hour += time->tm_min / 60;
    355         time->tm_min %= 60;
    356         if (time->tm_min < 0) {
    357             time->tm_min += 60;
    358             time->tm_hour--;
    359         }
    360     }
    361 
    362     if (time->tm_hour < 0 || time->tm_hour >= 24) {
    363         time->tm_mday += time->tm_hour / 24;
    364         time->tm_hour %= 24;
    365         if (time->tm_hour < 0) {
    366             time->tm_hour += 24;
    367             time->tm_mday--;
    368         }
    369     }
    370 
    371     /* Normalize month and year before mday */
    372     if (time->tm_month < 0 || time->tm_month >= 12) {
    373         time->tm_year += time->tm_month / 12;
    374         time->tm_month %= 12;
    375         if (time->tm_month < 0) {
    376             time->tm_month += 12;
    377             time->tm_year--;
    378         }
    379     }
    380 
    381     /* Now that month and year are in proper range, normalize mday */
    382 
    383     if (time->tm_mday < 1) {
    384         /* mday too small */
    385         do {
    386             /* the previous month */
    387             time->tm_month--;
    388             if (time->tm_month < 0) {
    389                 time->tm_month = 11;
    390                 time->tm_year--;
    391             }
    392             time->tm_mday += nDays[IsLeapYear(time->tm_year)][time->tm_month];
    393         } while (time->tm_mday < 1);
    394     } else {
    395         daysInMonth = nDays[IsLeapYear(time->tm_year)][time->tm_month];
    396         while (time->tm_mday > daysInMonth) {
    397             /* mday too large */
    398             time->tm_mday -= daysInMonth;
    399             time->tm_month++;
    400             if (time->tm_month > 11) {
    401                 time->tm_month = 0;
    402                 time->tm_year++;
    403             }
    404             daysInMonth = nDays[IsLeapYear(time->tm_year)][time->tm_month];
    405         }
    406     }
    407 
    408     /* Recompute yday and wday */
    409     time->tm_yday = time->tm_mday +
    410             lastDayOfMonth[IsLeapYear(time->tm_year)][time->tm_month];
    411 
    412     numDays = DAYS_BETWEEN_YEARS(1970, time->tm_year) + time->tm_yday;
    413     time->tm_wday = (numDays + 4) % 7;
    414     if (time->tm_wday < 0) {
    415         time->tm_wday += 7;
    416     }
    417 
    418     /* Recompute time parameters */
    419 
    420     time->tm_params = params(time);
    421 
    422     ApplySecOffset(time, time->tm_params.tp_gmt_offset
    423             + time->tm_params.tp_dst_offset);
    424 }
    425 
    426 /*
    427  *------------------------------------------------------------------------
    428  *
    429  * PR_GMTParameters --
    430  *
    431  *     Returns the PRTimeParameters for Greenwich Mean Time.
    432  *     Trivially, both the tp_gmt_offset and tp_dst_offset fields are 0.
    433  *
    434  *------------------------------------------------------------------------
    435  */
    436 
    437 PRTimeParameters
    438 PR_GMTParameters(const PRExplodedTime *gmt)
    439 {
    440 #if defined(XP_MAC)
    441 #pragma unused (gmt)
    442 #endif
    443 
    444     PRTimeParameters retVal = { 0, 0 };
    445     return retVal;
    446 }
    447 
    448 /*
    449  * The following code implements PR_ParseTimeString().  It is based on
    450  * ns/lib/xp/xp_time.c, revision 1.25, by Jamie Zawinski <jwz (at) netscape.com>.
    451  */
    452 
    453 /*
    454  * We only recognize the abbreviations of a small subset of time zones
    455  * in North America, Europe, and Japan.
    456  *
    457  * PST/PDT: Pacific Standard/Daylight Time
    458  * MST/MDT: Mountain Standard/Daylight Time
    459  * CST/CDT: Central Standard/Daylight Time
    460  * EST/EDT: Eastern Standard/Daylight Time
    461  * AST: Atlantic Standard Time
    462  * NST: Newfoundland Standard Time
    463  * GMT: Greenwich Mean Time
    464  * BST: British Summer Time
    465  * MET: Middle Europe Time
    466  * EET: Eastern Europe Time
    467  * JST: Japan Standard Time
    468  */
    469 
    470 typedef enum
    471 {
    472   TT_UNKNOWN,
    473 
    474   TT_SUN, TT_MON, TT_TUE, TT_WED, TT_THU, TT_FRI, TT_SAT,
    475 
    476   TT_JAN, TT_FEB, TT_MAR, TT_APR, TT_MAY, TT_JUN,
    477   TT_JUL, TT_AUG, TT_SEP, TT_OCT, TT_NOV, TT_DEC,
    478 
    479   TT_PST, TT_PDT, TT_MST, TT_MDT, TT_CST, TT_CDT, TT_EST, TT_EDT,
    480   TT_AST, TT_NST, TT_GMT, TT_BST, TT_MET, TT_EET, TT_JST
    481 } TIME_TOKEN;
    482 
    483 /*
    484  * This parses a time/date string into a PRTime
    485  * (microseconds after "1-Jan-1970 00:00:00 GMT").
    486  * It returns PR_SUCCESS on success, and PR_FAILURE
    487  * if the time/date string can't be parsed.
    488  *
    489  * Many formats are handled, including:
    490  *
    491  *   14 Apr 89 03:20:12
    492  *   14 Apr 89 03:20 GMT
    493  *   Fri, 17 Mar 89 4:01:33
    494  *   Fri, 17 Mar 89 4:01 GMT
    495  *   Mon Jan 16 16:12 PDT 1989
    496  *   Mon Jan 16 16:12 +0130 1989
    497  *   6 May 1992 16:41-JST (Wednesday)
    498  *   22-AUG-1993 10:59:12.82
    499  *   22-AUG-1993 10:59pm
    500  *   22-AUG-1993 12:59am
    501  *   22-AUG-1993 12:59 PM
    502  *   Friday, August 04, 1995 3:54 PM
    503  *   06/21/95 04:24:34 PM
    504  *   20/06/95 21:07
    505  *   95-06-08 19:32:48 EDT
    506  *
    507  * If the input string doesn't contain a description of the timezone,
    508  * we consult the `default_to_gmt' to decide whether the string should
    509  * be interpreted relative to the local time zone (PR_FALSE) or GMT (PR_TRUE).
    510  * The correct value for this argument depends on what standard specified
    511  * the time string which you are parsing.
    512  */
    513 
    514 PRStatus
    515 PR_ParseTimeString(
    516         const char *string,
    517         PRBool default_to_gmt,
    518         PRTime *result_imploded)
    519 {
    520   PRExplodedTime tm;
    521   PRExplodedTime *result = &tm;
    522   TIME_TOKEN dotw = TT_UNKNOWN;
    523   TIME_TOKEN month = TT_UNKNOWN;
    524   TIME_TOKEN zone = TT_UNKNOWN;
    525   int zone_offset = -1;
    526   int dst_offset = 0;
    527   int date = -1;
    528   PRInt32 year = -1;
    529   int hour = -1;
    530   int min = -1;
    531   int sec = -1;
    532 
    533   const char *rest = string;
    534 
    535   int iterations = 0;
    536 
    537   PR_ASSERT(string && result);
    538   if (!string || !result) return PR_FAILURE;
    539 
    540   while (*rest)
    541         {
    542 
    543           if (iterations++ > 1000)
    544                 {
    545                   return PR_FAILURE;
    546                 }
    547 
    548           switch (*rest)
    549                 {
    550                 case 'a': case 'A':
    551                   if (month == TT_UNKNOWN &&
    552                           (rest[1] == 'p' || rest[1] == 'P') &&
    553                           (rest[2] == 'r' || rest[2] == 'R'))
    554                         month = TT_APR;
    555                   else if (zone == TT_UNKNOWN &&
    556                                    (rest[1] == 's' || rest[1] == 'S') &&
    557                                    (rest[2] == 't' || rest[2] == 'T'))
    558                         zone = TT_AST;
    559                   else if (month == TT_UNKNOWN &&
    560                                    (rest[1] == 'u' || rest[1] == 'U') &&
    561                                    (rest[2] == 'g' || rest[2] == 'G'))
    562                         month = TT_AUG;
    563                   break;
    564                 case 'b': case 'B':
    565                   if (zone == TT_UNKNOWN &&
    566                           (rest[1] == 's' || rest[1] == 'S') &&
    567                           (rest[2] == 't' || rest[2] == 'T'))
    568                         zone = TT_BST;
    569                   break;
    570                 case 'c': case 'C':
    571                   if (zone == TT_UNKNOWN &&
    572                           (rest[1] == 'd' || rest[1] == 'D') &&
    573                           (rest[2] == 't' || rest[2] == 'T'))
    574                         zone = TT_CDT;
    575                   else if (zone == TT_UNKNOWN &&
    576                                    (rest[1] == 's' || rest[1] == 'S') &&
    577                                    (rest[2] == 't' || rest[2] == 'T'))
    578                         zone = TT_CST;
    579                   break;
    580                 case 'd': case 'D':
    581                   if (month == TT_UNKNOWN &&
    582                           (rest[1] == 'e' || rest[1] == 'E') &&
    583                           (rest[2] == 'c' || rest[2] == 'C'))
    584                         month = TT_DEC;
    585                   break;
    586                 case 'e': case 'E':
    587                   if (zone == TT_UNKNOWN &&
    588                           (rest[1] == 'd' || rest[1] == 'D') &&
    589                           (rest[2] == 't' || rest[2] == 'T'))
    590                         zone = TT_EDT;
    591                   else if (zone == TT_UNKNOWN &&
    592                                    (rest[1] == 'e' || rest[1] == 'E') &&
    593                                    (rest[2] == 't' || rest[2] == 'T'))
    594                         zone = TT_EET;
    595                   else if (zone == TT_UNKNOWN &&
    596                                    (rest[1] == 's' || rest[1] == 'S') &&
    597                                    (rest[2] == 't' || rest[2] == 'T'))
    598                         zone = TT_EST;
    599                   break;
    600                 case 'f': case 'F':
    601                   if (month == TT_UNKNOWN &&
    602                           (rest[1] == 'e' || rest[1] == 'E') &&
    603                           (rest[2] == 'b' || rest[2] == 'B'))
    604                         month = TT_FEB;
    605                   else if (dotw == TT_UNKNOWN &&
    606                                    (rest[1] == 'r' || rest[1] == 'R') &&
    607                                    (rest[2] == 'i' || rest[2] == 'I'))
    608                         dotw = TT_FRI;
    609                   break;
    610                 case 'g': case 'G':
    611                   if (zone == TT_UNKNOWN &&
    612                           (rest[1] == 'm' || rest[1] == 'M') &&
    613                           (rest[2] == 't' || rest[2] == 'T'))
    614                         zone = TT_GMT;
    615                   break;
    616                 case 'j': case 'J':
    617                   if (month == TT_UNKNOWN &&
    618                           (rest[1] == 'a' || rest[1] == 'A') &&
    619                           (rest[2] == 'n' || rest[2] == 'N'))
    620                         month = TT_JAN;
    621                   else if (zone == TT_UNKNOWN &&
    622                                    (rest[1] == 's' || rest[1] == 'S') &&
    623                                    (rest[2] == 't' || rest[2] == 'T'))
    624                         zone = TT_JST;
    625                   else if (month == TT_UNKNOWN &&
    626                                    (rest[1] == 'u' || rest[1] == 'U') &&
    627                                    (rest[2] == 'l' || rest[2] == 'L'))
    628                         month = TT_JUL;
    629                   else if (month == TT_UNKNOWN &&
    630                                    (rest[1] == 'u' || rest[1] == 'U') &&
    631                                    (rest[2] == 'n' || rest[2] == 'N'))
    632                         month = TT_JUN;
    633                   break;
    634                 case 'm': case 'M':
    635                   if (month == TT_UNKNOWN &&
    636                           (rest[1] == 'a' || rest[1] == 'A') &&
    637                           (rest[2] == 'r' || rest[2] == 'R'))
    638                         month = TT_MAR;
    639                   else if (month == TT_UNKNOWN &&
    640                                    (rest[1] == 'a' || rest[1] == 'A') &&
    641                                    (rest[2] == 'y' || rest[2] == 'Y'))
    642                         month = TT_MAY;
    643                   else if (zone == TT_UNKNOWN &&
    644                                    (rest[1] == 'd' || rest[1] == 'D') &&
    645                                    (rest[2] == 't' || rest[2] == 'T'))
    646                         zone = TT_MDT;
    647                   else if (zone == TT_UNKNOWN &&
    648                                    (rest[1] == 'e' || rest[1] == 'E') &&
    649                                    (rest[2] == 't' || rest[2] == 'T'))
    650                         zone = TT_MET;
    651                   else if (dotw == TT_UNKNOWN &&
    652                                    (rest[1] == 'o' || rest[1] == 'O') &&
    653                                    (rest[2] == 'n' || rest[2] == 'N'))
    654                         dotw = TT_MON;
    655                   else if (zone == TT_UNKNOWN &&
    656                                    (rest[1] == 's' || rest[1] == 'S') &&
    657                                    (rest[2] == 't' || rest[2] == 'T'))
    658                         zone = TT_MST;
    659                   break;
    660                 case 'n': case 'N':
    661                   if (month == TT_UNKNOWN &&
    662                           (rest[1] == 'o' || rest[1] == 'O') &&
    663                           (rest[2] == 'v' || rest[2] == 'V'))
    664                         month = TT_NOV;
    665                   else if (zone == TT_UNKNOWN &&
    666                                    (rest[1] == 's' || rest[1] == 'S') &&
    667                                    (rest[2] == 't' || rest[2] == 'T'))
    668                         zone = TT_NST;
    669                   break;
    670                 case 'o': case 'O':
    671                   if (month == TT_UNKNOWN &&
    672                           (rest[1] == 'c' || rest[1] == 'C') &&
    673                           (rest[2] == 't' || rest[2] == 'T'))
    674                         month = TT_OCT;
    675                   break;
    676                 case 'p': case 'P':
    677                   if (zone == TT_UNKNOWN &&
    678                           (rest[1] == 'd' || rest[1] == 'D') &&
    679                           (rest[2] == 't' || rest[2] == 'T'))
    680                         zone = TT_PDT;
    681                   else if (zone == TT_UNKNOWN &&
    682                                    (rest[1] == 's' || rest[1] == 'S') &&
    683                                    (rest[2] == 't' || rest[2] == 'T'))
    684                         zone = TT_PST;
    685                   break;
    686                 case 's': case 'S':
    687                   if (dotw == TT_UNKNOWN &&
    688                           (rest[1] == 'a' || rest[1] == 'A') &&
    689                           (rest[2] == 't' || rest[2] == 'T'))
    690                         dotw = TT_SAT;
    691                   else if (month == TT_UNKNOWN &&
    692                                    (rest[1] == 'e' || rest[1] == 'E') &&
    693                                    (rest[2] == 'p' || rest[2] == 'P'))
    694                         month = TT_SEP;
    695                   else if (dotw == TT_UNKNOWN &&
    696                                    (rest[1] == 'u' || rest[1] == 'U') &&
    697                                    (rest[2] == 'n' || rest[2] == 'N'))
    698                         dotw = TT_SUN;
    699                   break;
    700                 case 't': case 'T':
    701                   if (dotw == TT_UNKNOWN &&
    702                           (rest[1] == 'h' || rest[1] == 'H') &&
    703                           (rest[2] == 'u' || rest[2] == 'U'))
    704                         dotw = TT_THU;
    705                   else if (dotw == TT_UNKNOWN &&
    706                                    (rest[1] == 'u' || rest[1] == 'U') &&
    707                                    (rest[2] == 'e' || rest[2] == 'E'))
    708                         dotw = TT_TUE;
    709                   break;
    710                 case 'u': case 'U':
    711                   if (zone == TT_UNKNOWN &&
    712                           (rest[1] == 't' || rest[1] == 'T') &&
    713                           !(rest[2] >= 'A' && rest[2] <= 'Z') &&
    714                           !(rest[2] >= 'a' && rest[2] <= 'z'))
    715                         /* UT is the same as GMT but UTx is not. */
    716                         zone = TT_GMT;
    717                   break;
    718                 case 'w': case 'W':
    719                   if (dotw == TT_UNKNOWN &&
    720                           (rest[1] == 'e' || rest[1] == 'E') &&
    721                           (rest[2] == 'd' || rest[2] == 'D'))
    722                         dotw = TT_WED;
    723                   break;
    724 
    725                 case '+': case '-':
    726                   {
    727                         const char *end;
    728                         int sign;
    729                         if (zone_offset != -1)
    730                           {
    731                                 /* already got one... */
    732                                 rest++;
    733                                 break;
    734                           }
    735                         if (zone != TT_UNKNOWN && zone != TT_GMT)
    736                           {
    737                                 /* GMT+0300 is legal, but PST+0300 is not. */
    738                                 rest++;
    739                                 break;
    740                           }
    741 
    742                         sign = ((*rest == '+') ? 1 : -1);
    743                         rest++; /* move over sign */
    744                         end = rest;
    745                         while (*end >= '0' && *end <= '9')
    746                           end++;
    747                         if (rest == end) /* no digits here */
    748                           break;
    749 
    750                         if ((end - rest) == 4)
    751                           /* offset in HHMM */
    752                           zone_offset = (((((rest[0]-'0')*10) + (rest[1]-'0')) * 60) +
    753                                                          (((rest[2]-'0')*10) + (rest[3]-'0')));
    754                         else if ((end - rest) == 2)
    755                           /* offset in hours */
    756                           zone_offset = (((rest[0]-'0')*10) + (rest[1]-'0')) * 60;
    757                         else if ((end - rest) == 1)
    758                           /* offset in hours */
    759                           zone_offset = (rest[0]-'0') * 60;
    760                         else
    761                           /* 3 or >4 */
    762                           break;
    763 
    764                         zone_offset *= sign;
    765                         zone = TT_GMT;
    766                         break;
    767                   }
    768 
    769                 case '0': case '1': case '2': case '3': case '4':
    770                 case '5': case '6': case '7': case '8': case '9':
    771                   {
    772                         int tmp_hour = -1;
    773                         int tmp_min = -1;
    774                         int tmp_sec = -1;
    775                         const char *end = rest + 1;
    776                         while (*end >= '0' && *end <= '9')
    777                           end++;
    778 
    779                         /* end is now the first character after a range of digits. */
    780 
    781                         if (*end == ':')
    782                           {
    783                                 if (hour >= 0 && min >= 0) /* already got it */
    784                                   break;
    785 
    786                                 /* We have seen "[0-9]+:", so this is probably HH:MM[:SS] */
    787                                 if ((end - rest) > 2)
    788                                   /* it is [0-9][0-9][0-9]+: */
    789                                   break;
    790                                 else if ((end - rest) == 2)
    791                                   tmp_hour = ((rest[0]-'0')*10 +
    792                                                           (rest[1]-'0'));
    793                                 else
    794                                   tmp_hour = (rest[0]-'0');
    795 
    796                                 /* move over the colon, and parse minutes */
    797 
    798                                 rest = ++end;
    799                                 while (*end >= '0' && *end <= '9')
    800                                   end++;
    801 
    802                                 if (end == rest)
    803                                   /* no digits after first colon? */
    804                                   break;
    805                                 else if ((end - rest) > 2)
    806                                   /* it is [0-9][0-9][0-9]+: */
    807                                   break;
    808                                 else if ((end - rest) == 2)
    809                                   tmp_min = ((rest[0]-'0')*10 +
    810                                                          (rest[1]-'0'));
    811                                 else
    812                                   tmp_min = (rest[0]-'0');
    813 
    814                                 /* now go for seconds */
    815                                 rest = end;
    816                                 if (*rest == ':')
    817                                   rest++;
    818                                 end = rest;
    819                                 while (*end >= '0' && *end <= '9')
    820                                   end++;
    821 
    822                                 if (end == rest)
    823                                   /* no digits after second colon - that's ok. */
    824                                   ;
    825                                 else if ((end - rest) > 2)
    826                                   /* it is [0-9][0-9][0-9]+: */
    827                                   break;
    828                                 else if ((end - rest) == 2)
    829                                   tmp_sec = ((rest[0]-'0')*10 +
    830                                                          (rest[1]-'0'));
    831                                 else
    832                                   tmp_sec = (rest[0]-'0');
    833 
    834                                 /* If we made it here, we've parsed hour and min,
    835                                    and possibly sec, so it worked as a unit. */
    836 
    837                                 /* skip over whitespace and see if there's an AM or PM
    838                                    directly following the time.
    839                                  */
    840                                 if (tmp_hour <= 12)
    841                                   {
    842                                         const char *s = end;
    843                                         while (*s && (*s == ' ' || *s == '\t'))
    844                                           s++;
    845                                         if ((s[0] == 'p' || s[0] == 'P') &&
    846                                                 (s[1] == 'm' || s[1] == 'M'))
    847                                           /* 10:05pm == 22:05, and 12:05pm == 12:05 */
    848                                           tmp_hour = (tmp_hour == 12 ? 12 : tmp_hour + 12);
    849                                         else if (tmp_hour == 12 &&
    850                                                          (s[0] == 'a' || s[0] == 'A') &&
    851                                                          (s[1] == 'm' || s[1] == 'M'))
    852                                           /* 12:05am == 00:05 */
    853                                           tmp_hour = 0;
    854                                   }
    855 
    856                                 hour = tmp_hour;
    857                                 min = tmp_min;
    858                                 sec = tmp_sec;
    859                                 rest = end;
    860                                 break;
    861                           }
    862                         else if ((*end == '/' || *end == '-') &&
    863                                          end[1] >= '0' && end[1] <= '9')
    864                           {
    865                                 /* Perhaps this is 6/16/95, 16/6/95, 6-16-95, or 16-6-95
    866                                    or even 95-06-05...
    867                                    #### But it doesn't handle 1995-06-22.
    868                                  */
    869                                 int n1, n2, n3;
    870                                 const char *s;
    871 
    872                                 if (month != TT_UNKNOWN)
    873                                   /* if we saw a month name, this can't be. */
    874                                   break;
    875 
    876                                 s = rest;
    877 
    878                                 n1 = (*s++ - '0');                                /* first 1 or 2 digits */
    879                                 if (*s >= '0' && *s <= '9')
    880                                   n1 = n1*10 + (*s++ - '0');
    881 
    882                                 if (*s != '/' && *s != '-')                /* slash */
    883                                   break;
    884                                 s++;
    885 
    886                                 if (*s < '0' || *s > '9')                /* second 1 or 2 digits */
    887                                   break;
    888                                 n2 = (*s++ - '0');
    889                                 if (*s >= '0' && *s <= '9')
    890                                   n2 = n2*10 + (*s++ - '0');
    891 
    892                                 if (*s != '/' && *s != '-')                /* slash */
    893                                   break;
    894                                 s++;
    895 
    896                                 if (*s < '0' || *s > '9')                /* third 1, 2, 4, or 5 digits */
    897                                   break;
    898                                 n3 = (*s++ - '0');
    899                                 if (*s >= '0' && *s <= '9')
    900                                   n3 = n3*10 + (*s++ - '0');
    901 
    902                                 if (*s >= '0' && *s <= '9')            /* optional digits 3, 4, and 5 */
    903                                   {
    904                                         n3 = n3*10 + (*s++ - '0');
    905                                         if (*s < '0' || *s > '9')
    906                                           break;
    907                                         n3 = n3*10 + (*s++ - '0');
    908                                         if (*s >= '0' && *s <= '9')
    909                                           n3 = n3*10 + (*s++ - '0');
    910                                   }
    911 
    912                                 if ((*s >= '0' && *s <= '9') ||        /* followed by non-alphanum */
    913                                         (*s >= 'A' && *s <= 'Z') ||
    914                                         (*s >= 'a' && *s <= 'z'))
    915                                   break;
    916 
    917                                 /* Ok, we parsed three 1-2 digit numbers, with / or -
    918                                    between them.  Now decide what the hell they are
    919                                    (DD/MM/YY or MM/DD/YY or YY/MM/DD.)
    920                                  */
    921 
    922                                 if (n1 > 31 || n1 == 0)  /* must be YY/MM/DD */
    923                                   {
    924                                         if (n2 > 12) break;
    925                                         if (n3 > 31) break;
    926                                         year = n1;
    927                                         if (year < 70)
    928                                             year += 2000;
    929                                         else if (year < 100)
    930                                             year += 1900;
    931                                         month = (TIME_TOKEN)(n2 + ((int)TT_JAN) - 1);
    932                                         date = n3;
    933                                         rest = s;
    934                                         break;
    935                                   }
    936 
    937                                 if (n1 > 12 && n2 > 12)  /* illegal */
    938                                   {
    939                                         rest = s;
    940                                         break;
    941                                   }
    942 
    943                                 if (n3 < 70)
    944                                     n3 += 2000;
    945                                 else if (n3 < 100)
    946                                     n3 += 1900;
    947 
    948                                 if (n1 > 12)  /* must be DD/MM/YY */
    949                                   {
    950                                         date = n1;
    951                                         month = (TIME_TOKEN)(n2 + ((int)TT_JAN) - 1);
    952                                         year = n3;
    953                                   }
    954                                 else                  /* assume MM/DD/YY */
    955                                   {
    956                                         /* #### In the ambiguous case, should we consult the
    957                                            locale to find out the local default? */
    958                                         month = (TIME_TOKEN)(n1 + ((int)TT_JAN) - 1);
    959                                         date = n2;
    960                                         year = n3;
    961                                   }
    962                                 rest = s;
    963                           }
    964                         else if ((*end >= 'A' && *end <= 'Z') ||
    965                                          (*end >= 'a' && *end <= 'z'))
    966                           /* Digits followed by non-punctuation - what's that? */
    967                           ;
    968                         else if ((end - rest) == 5)                /* five digits is a year */
    969                           year = (year < 0
    970                                           ? ((rest[0]-'0')*10000L +
    971                                                  (rest[1]-'0')*1000L +
    972                                                  (rest[2]-'0')*100L +
    973                                                  (rest[3]-'0')*10L +
    974                                                  (rest[4]-'0'))
    975                                           : year);
    976                         else if ((end - rest) == 4)                /* four digits is a year */
    977                           year = (year < 0
    978                                           ? ((rest[0]-'0')*1000L +
    979                                                  (rest[1]-'0')*100L +
    980                                                  (rest[2]-'0')*10L +
    981                                                  (rest[3]-'0'))
    982                                           : year);
    983                         else if ((end - rest) == 2)                /* two digits - date or year */
    984                           {
    985                                 int n = ((rest[0]-'0')*10 +
    986                                                  (rest[1]-'0'));
    987                                 /* If we don't have a date (day of the month) and we see a number
    988                                      less than 32, then assume that is the date.
    989 
    990                                          Otherwise, if we have a date and not a year, assume this is the
    991                                          year.  If it is less than 70, then assume it refers to the 21st
    992                                          century.  If it is two digits (>= 70), assume it refers to this
    993                                          century.  Otherwise, assume it refers to an unambiguous year.
    994 
    995                                          The world will surely end soon.
    996                                    */
    997                                 if (date < 0 && n < 32)
    998                                   date = n;
    999                                 else if (year < 0)
   1000                                   {
   1001                                         if (n < 70)
   1002                                           year = 2000 + n;
   1003                                         else if (n < 100)
   1004                                           year = 1900 + n;
   1005                                         else
   1006                                           year = n;
   1007                                   }
   1008                                 /* else what the hell is this. */
   1009                           }
   1010                         else if ((end - rest) == 1)                /* one digit - date */
   1011                           date = (date < 0 ? (rest[0]-'0') : date);
   1012                         /* else, three or more than five digits - what's that? */
   1013 
   1014                         break;
   1015                   }
   1016                 }
   1017 
   1018           /* Skip to the end of this token, whether we parsed it or not.
   1019                  Tokens are delimited by whitespace, or ,;-/
   1020                  But explicitly not :+-.
   1021            */
   1022           while (*rest &&
   1023                          *rest != ' ' && *rest != '\t' &&
   1024                          *rest != ',' && *rest != ';' &&
   1025                          *rest != '-' && *rest != '+' &&
   1026                          *rest != '/' &&
   1027                          *rest != '(' && *rest != ')' && *rest != '[' && *rest != ']')
   1028                 rest++;
   1029           /* skip over uninteresting chars. */
   1030         SKIP_MORE:
   1031           while (*rest &&
   1032                          (*rest == ' ' || *rest == '\t' ||
   1033                           *rest == ',' || *rest == ';' || *rest == '/' ||
   1034                           *rest == '(' || *rest == ')' || *rest == '[' || *rest == ']'))
   1035                 rest++;
   1036 
   1037           /* "-" is ignored at the beginning of a token if we have not yet
   1038                  parsed a year (e.g., the second "-" in "30-AUG-1966"), or if
   1039                  the character after the dash is not a digit. */
   1040           if (*rest == '-' && ((rest > string && isalpha(rest[-1]) && year < 0)
   1041               || rest[1] < '0' || rest[1] > '9'))
   1042                 {
   1043                   rest++;
   1044                   goto SKIP_MORE;
   1045                 }
   1046 
   1047         }
   1048 
   1049   if (zone != TT_UNKNOWN && zone_offset == -1)
   1050         {
   1051           switch (zone)
   1052                 {
   1053                 case TT_PST: zone_offset = -8 * 60; break;
   1054                 case TT_PDT: zone_offset = -8 * 60; dst_offset = 1 * 60; break;
   1055                 case TT_MST: zone_offset = -7 * 60; break;
   1056                 case TT_MDT: zone_offset = -7 * 60; dst_offset = 1 * 60; break;
   1057                 case TT_CST: zone_offset = -6 * 60; break;
   1058                 case TT_CDT: zone_offset = -6 * 60; dst_offset = 1 * 60; break;
   1059                 case TT_EST: zone_offset = -5 * 60; break;
   1060                 case TT_EDT: zone_offset = -5 * 60; dst_offset = 1 * 60; break;
   1061                 case TT_AST: zone_offset = -4 * 60; break;
   1062                 case TT_NST: zone_offset = -3 * 60 - 30; break;
   1063                 case TT_GMT: zone_offset =  0 * 60; break;
   1064                 case TT_BST: zone_offset =  0 * 60; dst_offset = 1 * 60; break;
   1065                 case TT_MET: zone_offset =  1 * 60; break;
   1066                 case TT_EET: zone_offset =  2 * 60; break;
   1067                 case TT_JST: zone_offset =  9 * 60; break;
   1068                 default:
   1069                   PR_ASSERT (0);
   1070                   break;
   1071                 }
   1072         }
   1073 
   1074   /* If we didn't find a year, month, or day-of-the-month, we can't
   1075          possibly parse this, and in fact, mktime() will do something random
   1076          (I'm seeing it return "Tue Feb  5 06:28:16 2036", which is no doubt
   1077          a numerologically significant date... */
   1078   if (month == TT_UNKNOWN || date == -1 || year == -1 || year > PR_INT16_MAX)
   1079       return PR_FAILURE;
   1080 
   1081   memset(result, 0, sizeof(*result));
   1082   if (sec != -1)
   1083         result->tm_sec = sec;
   1084   if (min != -1)
   1085         result->tm_min = min;
   1086   if (hour != -1)
   1087         result->tm_hour = hour;
   1088   if (date != -1)
   1089         result->tm_mday = date;
   1090   if (month != TT_UNKNOWN)
   1091         result->tm_month = (((int)month) - ((int)TT_JAN));
   1092   if (year != -1)
   1093         result->tm_year = year;
   1094   if (dotw != TT_UNKNOWN)
   1095         result->tm_wday = (((int)dotw) - ((int)TT_SUN));
   1096   /*
   1097    * Mainly to compute wday and yday, but normalized time is also required
   1098    * by the check below that works around a Visual C++ 2005 mktime problem.
   1099    */
   1100   PR_NormalizeTime(result, PR_GMTParameters);
   1101   /* The remaining work is to set the gmt and dst offsets in tm_params. */
   1102 
   1103   if (zone == TT_UNKNOWN && default_to_gmt)
   1104         {
   1105           /* No zone was specified, so pretend the zone was GMT. */
   1106           zone = TT_GMT;
   1107           zone_offset = 0;
   1108         }
   1109 
   1110   if (zone_offset == -1)
   1111          {
   1112            /* no zone was specified, and we're to assume that everything
   1113              is local. */
   1114           struct tm localTime;
   1115           time_t secs;
   1116 
   1117           PR_ASSERT(result->tm_month > -1 &&
   1118                     result->tm_mday > 0 &&
   1119                     result->tm_hour > -1 &&
   1120                     result->tm_min > -1 &&
   1121                     result->tm_sec > -1);
   1122 
   1123             /*
   1124              * To obtain time_t from a tm structure representing the local
   1125              * time, we call mktime().  However, we need to see if we are
   1126              * on 1-Jan-1970 or before.  If we are, we can't call mktime()
   1127              * because mktime() will crash on win16. In that case, we
   1128              * calculate zone_offset based on the zone offset at
   1129              * 00:00:00, 2 Jan 1970 GMT, and subtract zone_offset from the
   1130              * date we are parsing to transform the date to GMT.  We also
   1131              * do so if mktime() returns (time_t) -1 (time out of range).
   1132            */
   1133 
   1134           /* month, day, hours, mins and secs are always non-negative
   1135              so we dont need to worry about them. */
   1136           if(result->tm_year >= 1970)
   1137                 {
   1138                   PRInt64 usec_per_sec;
   1139 
   1140                   localTime.tm_sec = result->tm_sec;
   1141                   localTime.tm_min = result->tm_min;
   1142                   localTime.tm_hour = result->tm_hour;
   1143                   localTime.tm_mday = result->tm_mday;
   1144                   localTime.tm_mon = result->tm_month;
   1145                   localTime.tm_year = result->tm_year - 1900;
   1146                   /* Set this to -1 to tell mktime "I don't care".  If you set
   1147                      it to 0 or 1, you are making assertions about whether the
   1148                      date you are handing it is in daylight savings mode or not;
   1149                      and if you're wrong, it will "fix" it for you. */
   1150                   localTime.tm_isdst = -1;
   1151 
   1152 #if _MSC_VER == 1400  /* 1400 = Visual C++ 2005 (8.0) */
   1153                   /*
   1154                    * mktime will return (time_t) -1 if the input is a date
   1155                    * after 23:59:59, December 31, 3000, US Pacific Time (not
   1156                    * UTC as documented):
   1157                    * http://msdn.microsoft.com/en-us/library/d1y53h2a(VS.80).aspx
   1158                    * But if the year is 3001, mktime also invokes the invalid
   1159                    * parameter handler, causing the application to crash.  This
   1160                    * problem has been reported in
   1161                    * http://connect.microsoft.com/VisualStudio/feedback/ViewFeedback.aspx?FeedbackID=266036.
   1162                    * We avoid this crash by not calling mktime if the date is
   1163                    * out of range.  To use a simple test that works in any time
   1164                    * zone, we consider year 3000 out of range as well.  (See
   1165                    * bug 480740.)
   1166                    */
   1167                   if (result->tm_year >= 3000) {
   1168                       /* Emulate what mktime would have done. */
   1169                       errno = EINVAL;
   1170                       secs = (time_t) -1;
   1171                   } else {
   1172                       secs = mktime(&localTime);
   1173                   }
   1174 #else
   1175                   secs = mktime(&localTime);
   1176 #endif
   1177                   if (secs != (time_t) -1)
   1178                     {
   1179                       PRTime usecs64;
   1180                       LL_I2L(usecs64, secs);
   1181                       LL_I2L(usec_per_sec, PR_USEC_PER_SEC);
   1182                       LL_MUL(usecs64, usecs64, usec_per_sec);
   1183                       *result_imploded = usecs64;
   1184                       return PR_SUCCESS;
   1185                     }
   1186                 }
   1187 
   1188                 /* So mktime() can't handle this case.  We assume the
   1189                    zone_offset for the date we are parsing is the same as
   1190                    the zone offset on 00:00:00 2 Jan 1970 GMT. */
   1191                 secs = 86400;
   1192                 localtime_r(&secs, &localTime);
   1193                 zone_offset = localTime.tm_min
   1194                               + 60 * localTime.tm_hour
   1195                               + 1440 * (localTime.tm_mday - 2);
   1196         }
   1197 
   1198   result->tm_params.tp_gmt_offset = zone_offset * 60;
   1199   result->tm_params.tp_dst_offset = dst_offset * 60;
   1200 
   1201   *result_imploded = PR_ImplodeTime(result);
   1202   return PR_SUCCESS;
   1203 }
   1204