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      1 /* Portions are Copyright (C) 2011 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/logging.h"
     67 #include "base/third_party/nspr/prtime.h"
     68 #include "build/build_config.h"
     69 
     70 #if defined(OS_WIN)
     71 #include <windows.h>
     72 #elif defined(OS_MACOSX)
     73 #include <CoreFoundation/CoreFoundation.h>
     74 #endif
     75 #include <errno.h>  /* for EINVAL */
     76 #include <time.h>
     77 
     78 /* Implements the Unix localtime_r() function for windows */
     79 #if defined(OS_WIN)
     80 static void localtime_r(const time_t* secs, struct tm* time) {
     81   (void) localtime_s(time, secs);
     82 }
     83 #endif
     84 
     85 /*
     86  *------------------------------------------------------------------------
     87  *
     88  * PR_ImplodeTime --
     89  *
     90  *     Cf. time_t mktime(struct tm *tp)
     91  *     Note that 1 year has < 2^25 seconds.  So an PRInt32 is large enough.
     92  *
     93  *------------------------------------------------------------------------
     94  */
     95 PRTime
     96 PR_ImplodeTime(const PRExplodedTime *exploded)
     97 {
     98     // This is important, we want to make sure multiplications are
     99     // done with the correct precision.
    100     static const PRTime kSecondsToMicroseconds = static_cast<PRTime>(1000000);
    101 #if defined(OS_WIN)
    102    // Create the system struct representing our exploded time.
    103     SYSTEMTIME st = {0};
    104     FILETIME ft = {0};
    105     ULARGE_INTEGER uli = {0};
    106 
    107     st.wYear = exploded->tm_year;
    108     st.wMonth = exploded->tm_month + 1;
    109     st.wDayOfWeek = exploded->tm_wday;
    110     st.wDay = exploded->tm_mday;
    111     st.wHour = exploded->tm_hour;
    112     st.wMinute = exploded->tm_min;
    113     st.wSecond = exploded->tm_sec;
    114     st.wMilliseconds = exploded->tm_usec/1000;
    115      // Convert to FILETIME.
    116     if (!SystemTimeToFileTime(&st, &ft)) {
    117       NOTREACHED() << "Unable to convert time";
    118       return 0;
    119     }
    120     // Apply offsets.
    121     uli.LowPart = ft.dwLowDateTime;
    122     uli.HighPart = ft.dwHighDateTime;
    123     // Convert from Windows epoch to NSPR epoch, and 100-nanoseconds units
    124     // to microsecond units.
    125     PRTime result =
    126         static_cast<PRTime>((uli.QuadPart / 10) - 11644473600000000i64);
    127     // Adjust for time zone and dst.  Convert from seconds to microseconds.
    128     result -= (exploded->tm_params.tp_gmt_offset +
    129                exploded->tm_params.tp_dst_offset) * kSecondsToMicroseconds;
    130     return result;
    131 #elif defined(OS_MACOSX)
    132     // Create the system struct representing our exploded time.
    133     CFGregorianDate gregorian_date;
    134     gregorian_date.year = exploded->tm_year;
    135     gregorian_date.month = exploded->tm_month + 1;
    136     gregorian_date.day = exploded->tm_mday;
    137     gregorian_date.hour = exploded->tm_hour;
    138     gregorian_date.minute = exploded->tm_min;
    139     gregorian_date.second = exploded->tm_sec;
    140 
    141     // Compute |absolute_time| in seconds, correct for gmt and dst
    142     // (note the combined offset will be negative when we need to add it), then
    143     // convert to microseconds which is what PRTime expects.
    144     CFAbsoluteTime absolute_time =
    145         CFGregorianDateGetAbsoluteTime(gregorian_date, NULL);
    146     PRTime result = static_cast<PRTime>(absolute_time);
    147     result -= exploded->tm_params.tp_gmt_offset +
    148               exploded->tm_params.tp_dst_offset;
    149     result += kCFAbsoluteTimeIntervalSince1970;  // PRTime epoch is 1970
    150     result *= kSecondsToMicroseconds;
    151     result += exploded->tm_usec;
    152     return result;
    153 #elif defined(OS_POSIX)
    154     struct tm exp_tm = {0};
    155     exp_tm.tm_sec  = exploded->tm_sec;
    156     exp_tm.tm_min  = exploded->tm_min;
    157     exp_tm.tm_hour = exploded->tm_hour;
    158     exp_tm.tm_mday = exploded->tm_mday;
    159     exp_tm.tm_mon  = exploded->tm_month;
    160     exp_tm.tm_year = exploded->tm_year - 1900;
    161 
    162     time_t absolute_time = timegm(&exp_tm);
    163 
    164     // If timegm returned -1.  Since we don't pass it a time zone, the only
    165     // valid case of returning -1 is 1 second before Epoch (Dec 31, 1969).
    166     if (absolute_time == -1 &&
    167         !(exploded->tm_year == 1969 && exploded->tm_month == 11 &&
    168         exploded->tm_mday == 31 && exploded->tm_hour == 23 &&
    169         exploded->tm_min == 59 && exploded->tm_sec == 59)) {
    170       // If we get here, time_t must be 32 bits.
    171       // Date was possibly too far in the future and would overflow.  Return
    172       // the most future date possible (year 2038).
    173       if (exploded->tm_year >= 1970)
    174         return INT_MAX * kSecondsToMicroseconds;
    175       // Date was possibly too far in the past and would underflow.  Return
    176       // the most past date possible (year 1901).
    177       return INT_MIN * kSecondsToMicroseconds;
    178     }
    179 
    180     PRTime result = static_cast<PRTime>(absolute_time);
    181     result -= exploded->tm_params.tp_gmt_offset +
    182               exploded->tm_params.tp_dst_offset;
    183     result *= kSecondsToMicroseconds;
    184     result += exploded->tm_usec;
    185     return result;
    186 #else
    187 #error No PR_ImplodeTime implemented on your platform.
    188 #endif
    189 }
    190 
    191 /*
    192  * The COUNT_LEAPS macro counts the number of leap years passed by
    193  * till the start of the given year Y.  At the start of the year 4
    194  * A.D. the number of leap years passed by is 0, while at the start of
    195  * the year 5 A.D. this count is 1. The number of years divisible by
    196  * 100 but not divisible by 400 (the non-leap years) is deducted from
    197  * the count to get the correct number of leap years.
    198  *
    199  * The COUNT_DAYS macro counts the number of days since 01/01/01 till the
    200  * start of the given year Y. The number of days at the start of the year
    201  * 1 is 0 while the number of days at the start of the year 2 is 365
    202  * (which is ((2)-1) * 365) and so on. The reference point is 01/01/01
    203  * midnight 00:00:00.
    204  */
    205 
    206 #define COUNT_LEAPS(Y)   ( ((Y)-1)/4 - ((Y)-1)/100 + ((Y)-1)/400 )
    207 #define COUNT_DAYS(Y)  ( ((Y)-1)*365 + COUNT_LEAPS(Y) )
    208 #define DAYS_BETWEEN_YEARS(A, B)  (COUNT_DAYS(B) - COUNT_DAYS(A))
    209 
    210 /*
    211  * Static variables used by functions in this file
    212  */
    213 
    214 /*
    215  * The following array contains the day of year for the last day of
    216  * each month, where index 1 is January, and day 0 is January 1.
    217  */
    218 
    219 static const int lastDayOfMonth[2][13] = {
    220     {-1, 30, 58, 89, 119, 150, 180, 211, 242, 272, 303, 333, 364},
    221     {-1, 30, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365}
    222 };
    223 
    224 /*
    225  * The number of days in a month
    226  */
    227 
    228 static const PRInt8 nDays[2][12] = {
    229     {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31},
    230     {31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}
    231 };
    232 
    233 /*
    234  *-------------------------------------------------------------------------
    235  *
    236  * IsLeapYear --
    237  *
    238  *     Returns 1 if the year is a leap year, 0 otherwise.
    239  *
    240  *-------------------------------------------------------------------------
    241  */
    242 
    243 static int IsLeapYear(PRInt16 year)
    244 {
    245     if ((year % 4 == 0 && year % 100 != 0) || year % 400 == 0)
    246         return 1;
    247     else
    248         return 0;
    249 }
    250 
    251 /*
    252  * 'secOffset' should be less than 86400 (i.e., a day).
    253  * 'time' should point to a normalized PRExplodedTime.
    254  */
    255 
    256 static void
    257 ApplySecOffset(PRExplodedTime *time, PRInt32 secOffset)
    258 {
    259     time->tm_sec += secOffset;
    260 
    261     /* Note that in this implementation we do not count leap seconds */
    262     if (time->tm_sec < 0 || time->tm_sec >= 60) {
    263         time->tm_min += time->tm_sec / 60;
    264         time->tm_sec %= 60;
    265         if (time->tm_sec < 0) {
    266             time->tm_sec += 60;
    267             time->tm_min--;
    268         }
    269     }
    270 
    271     if (time->tm_min < 0 || time->tm_min >= 60) {
    272         time->tm_hour += time->tm_min / 60;
    273         time->tm_min %= 60;
    274         if (time->tm_min < 0) {
    275             time->tm_min += 60;
    276             time->tm_hour--;
    277         }
    278     }
    279 
    280     if (time->tm_hour < 0) {
    281         /* Decrement mday, yday, and wday */
    282         time->tm_hour += 24;
    283         time->tm_mday--;
    284         time->tm_yday--;
    285         if (time->tm_mday < 1) {
    286             time->tm_month--;
    287             if (time->tm_month < 0) {
    288                 time->tm_month = 11;
    289                 time->tm_year--;
    290                 if (IsLeapYear(time->tm_year))
    291                     time->tm_yday = 365;
    292                 else
    293                     time->tm_yday = 364;
    294             }
    295             time->tm_mday = nDays[IsLeapYear(time->tm_year)][time->tm_month];
    296         }
    297         time->tm_wday--;
    298         if (time->tm_wday < 0)
    299             time->tm_wday = 6;
    300     } else if (time->tm_hour > 23) {
    301         /* Increment mday, yday, and wday */
    302         time->tm_hour -= 24;
    303         time->tm_mday++;
    304         time->tm_yday++;
    305         if (time->tm_mday >
    306                 nDays[IsLeapYear(time->tm_year)][time->tm_month]) {
    307             time->tm_mday = 1;
    308             time->tm_month++;
    309             if (time->tm_month > 11) {
    310                 time->tm_month = 0;
    311                 time->tm_year++;
    312                 time->tm_yday = 0;
    313             }
    314         }
    315         time->tm_wday++;
    316         if (time->tm_wday > 6)
    317             time->tm_wday = 0;
    318     }
    319 }
    320 
    321 void
    322 PR_NormalizeTime(PRExplodedTime *time, PRTimeParamFn params)
    323 {
    324     int daysInMonth;
    325     PRInt32 numDays;
    326 
    327     /* Get back to GMT */
    328     time->tm_sec -= time->tm_params.tp_gmt_offset
    329             + time->tm_params.tp_dst_offset;
    330     time->tm_params.tp_gmt_offset = 0;
    331     time->tm_params.tp_dst_offset = 0;
    332 
    333     /* Now normalize GMT */
    334 
    335     if (time->tm_usec < 0 || time->tm_usec >= 1000000) {
    336         time->tm_sec +=  time->tm_usec / 1000000;
    337         time->tm_usec %= 1000000;
    338         if (time->tm_usec < 0) {
    339             time->tm_usec += 1000000;
    340             time->tm_sec--;
    341         }
    342     }
    343 
    344     /* Note that we do not count leap seconds in this implementation */
    345     if (time->tm_sec < 0 || time->tm_sec >= 60) {
    346         time->tm_min += time->tm_sec / 60;
    347         time->tm_sec %= 60;
    348         if (time->tm_sec < 0) {
    349             time->tm_sec += 60;
    350             time->tm_min--;
    351         }
    352     }
    353 
    354     if (time->tm_min < 0 || time->tm_min >= 60) {
    355         time->tm_hour += time->tm_min / 60;
    356         time->tm_min %= 60;
    357         if (time->tm_min < 0) {
    358             time->tm_min += 60;
    359             time->tm_hour--;
    360         }
    361     }
    362 
    363     if (time->tm_hour < 0 || time->tm_hour >= 24) {
    364         time->tm_mday += time->tm_hour / 24;
    365         time->tm_hour %= 24;
    366         if (time->tm_hour < 0) {
    367             time->tm_hour += 24;
    368             time->tm_mday--;
    369         }
    370     }
    371 
    372     /* Normalize month and year before mday */
    373     if (time->tm_month < 0 || time->tm_month >= 12) {
    374         time->tm_year += time->tm_month / 12;
    375         time->tm_month %= 12;
    376         if (time->tm_month < 0) {
    377             time->tm_month += 12;
    378             time->tm_year--;
    379         }
    380     }
    381 
    382     /* Now that month and year are in proper range, normalize mday */
    383 
    384     if (time->tm_mday < 1) {
    385         /* mday too small */
    386         do {
    387             /* the previous month */
    388             time->tm_month--;
    389             if (time->tm_month < 0) {
    390                 time->tm_month = 11;
    391                 time->tm_year--;
    392             }
    393             time->tm_mday += nDays[IsLeapYear(time->tm_year)][time->tm_month];
    394         } while (time->tm_mday < 1);
    395     } else {
    396         daysInMonth = nDays[IsLeapYear(time->tm_year)][time->tm_month];
    397         while (time->tm_mday > daysInMonth) {
    398             /* mday too large */
    399             time->tm_mday -= daysInMonth;
    400             time->tm_month++;
    401             if (time->tm_month > 11) {
    402                 time->tm_month = 0;
    403                 time->tm_year++;
    404             }
    405             daysInMonth = nDays[IsLeapYear(time->tm_year)][time->tm_month];
    406         }
    407     }
    408 
    409     /* Recompute yday and wday */
    410     time->tm_yday = time->tm_mday +
    411             lastDayOfMonth[IsLeapYear(time->tm_year)][time->tm_month];
    412 
    413     numDays = DAYS_BETWEEN_YEARS(1970, time->tm_year) + time->tm_yday;
    414     time->tm_wday = (numDays + 4) % 7;
    415     if (time->tm_wday < 0) {
    416         time->tm_wday += 7;
    417     }
    418 
    419     /* Recompute time parameters */
    420 
    421     time->tm_params = params(time);
    422 
    423     ApplySecOffset(time, time->tm_params.tp_gmt_offset
    424             + time->tm_params.tp_dst_offset);
    425 }
    426 
    427 /*
    428  *------------------------------------------------------------------------
    429  *
    430  * PR_GMTParameters --
    431  *
    432  *     Returns the PRTimeParameters for Greenwich Mean Time.
    433  *     Trivially, both the tp_gmt_offset and tp_dst_offset fields are 0.
    434  *
    435  *------------------------------------------------------------------------
    436  */
    437 
    438 PRTimeParameters
    439 PR_GMTParameters(const PRExplodedTime *gmt)
    440 {
    441 #if defined(XP_MAC)
    442 #pragma unused (gmt)
    443 #endif
    444 
    445     PRTimeParameters retVal = { 0, 0 };
    446     return retVal;
    447 }
    448 
    449 /*
    450  * The following code implements PR_ParseTimeString().  It is based on
    451  * ns/lib/xp/xp_time.c, revision 1.25, by Jamie Zawinski <jwz (at) netscape.com>.
    452  */
    453 
    454 /*
    455  * We only recognize the abbreviations of a small subset of time zones
    456  * in North America, Europe, and Japan.
    457  *
    458  * PST/PDT: Pacific Standard/Daylight Time
    459  * MST/MDT: Mountain Standard/Daylight Time
    460  * CST/CDT: Central Standard/Daylight Time
    461  * EST/EDT: Eastern Standard/Daylight Time
    462  * AST: Atlantic Standard Time
    463  * NST: Newfoundland Standard Time
    464  * GMT: Greenwich Mean Time
    465  * BST: British Summer Time
    466  * MET: Middle Europe Time
    467  * EET: Eastern Europe Time
    468  * JST: Japan Standard Time
    469  */
    470 
    471 typedef enum
    472 {
    473   TT_UNKNOWN,
    474 
    475   TT_SUN, TT_MON, TT_TUE, TT_WED, TT_THU, TT_FRI, TT_SAT,
    476 
    477   TT_JAN, TT_FEB, TT_MAR, TT_APR, TT_MAY, TT_JUN,
    478   TT_JUL, TT_AUG, TT_SEP, TT_OCT, TT_NOV, TT_DEC,
    479 
    480   TT_PST, TT_PDT, TT_MST, TT_MDT, TT_CST, TT_CDT, TT_EST, TT_EDT,
    481   TT_AST, TT_NST, TT_GMT, TT_BST, TT_MET, TT_EET, TT_JST
    482 } TIME_TOKEN;
    483 
    484 /*
    485  * This parses a time/date string into a PRTime
    486  * (microseconds after "1-Jan-1970 00:00:00 GMT").
    487  * It returns PR_SUCCESS on success, and PR_FAILURE
    488  * if the time/date string can't be parsed.
    489  *
    490  * Many formats are handled, including:
    491  *
    492  *   14 Apr 89 03:20:12
    493  *   14 Apr 89 03:20 GMT
    494  *   Fri, 17 Mar 89 4:01:33
    495  *   Fri, 17 Mar 89 4:01 GMT
    496  *   Mon Jan 16 16:12 PDT 1989
    497  *   Mon Jan 16 16:12 +0130 1989
    498  *   6 May 1992 16:41-JST (Wednesday)
    499  *   22-AUG-1993 10:59:12.82
    500  *   22-AUG-1993 10:59pm
    501  *   22-AUG-1993 12:59am
    502  *   22-AUG-1993 12:59 PM
    503  *   Friday, August 04, 1995 3:54 PM
    504  *   06/21/95 04:24:34 PM
    505  *   20/06/95 21:07
    506  *   95-06-08 19:32:48 EDT
    507  *
    508  * If the input string doesn't contain a description of the timezone,
    509  * we consult the `default_to_gmt' to decide whether the string should
    510  * be interpreted relative to the local time zone (PR_FALSE) or GMT (PR_TRUE).
    511  * The correct value for this argument depends on what standard specified
    512  * the time string which you are parsing.
    513  */
    514 
    515 PRStatus
    516 PR_ParseTimeString(
    517         const char *string,
    518         PRBool default_to_gmt,
    519         PRTime *result_imploded)
    520 {
    521   PRExplodedTime tm;
    522   PRExplodedTime *result = &tm;
    523   TIME_TOKEN dotw = TT_UNKNOWN;
    524   TIME_TOKEN month = TT_UNKNOWN;
    525   TIME_TOKEN zone = TT_UNKNOWN;
    526   int zone_offset = -1;
    527   int dst_offset = 0;
    528   int date = -1;
    529   PRInt32 year = -1;
    530   int hour = -1;
    531   int min = -1;
    532   int sec = -1;
    533 
    534   const char *rest = string;
    535 
    536   int iterations = 0;
    537 
    538   PR_ASSERT(string && result);
    539   if (!string || !result) return PR_FAILURE;
    540 
    541   while (*rest)
    542         {
    543 
    544           if (iterations++ > 1000)
    545                 {
    546                   return PR_FAILURE;
    547                 }
    548 
    549           switch (*rest)
    550                 {
    551                 case 'a': case 'A':
    552                   if (month == TT_UNKNOWN &&
    553                           (rest[1] == 'p' || rest[1] == 'P') &&
    554                           (rest[2] == 'r' || rest[2] == 'R'))
    555                         month = TT_APR;
    556                   else if (zone == TT_UNKNOWN &&
    557                                    (rest[1] == 's' || rest[1] == 'S') &&
    558                                    (rest[2] == 't' || rest[2] == 'T'))
    559                         zone = TT_AST;
    560                   else if (month == TT_UNKNOWN &&
    561                                    (rest[1] == 'u' || rest[1] == 'U') &&
    562                                    (rest[2] == 'g' || rest[2] == 'G'))
    563                         month = TT_AUG;
    564                   break;
    565                 case 'b': case 'B':
    566                   if (zone == TT_UNKNOWN &&
    567                           (rest[1] == 's' || rest[1] == 'S') &&
    568                           (rest[2] == 't' || rest[2] == 'T'))
    569                         zone = TT_BST;
    570                   break;
    571                 case 'c': case 'C':
    572                   if (zone == TT_UNKNOWN &&
    573                           (rest[1] == 'd' || rest[1] == 'D') &&
    574                           (rest[2] == 't' || rest[2] == 'T'))
    575                         zone = TT_CDT;
    576                   else if (zone == TT_UNKNOWN &&
    577                                    (rest[1] == 's' || rest[1] == 'S') &&
    578                                    (rest[2] == 't' || rest[2] == 'T'))
    579                         zone = TT_CST;
    580                   break;
    581                 case 'd': case 'D':
    582                   if (month == TT_UNKNOWN &&
    583                           (rest[1] == 'e' || rest[1] == 'E') &&
    584                           (rest[2] == 'c' || rest[2] == 'C'))
    585                         month = TT_DEC;
    586                   break;
    587                 case 'e': case 'E':
    588                   if (zone == TT_UNKNOWN &&
    589                           (rest[1] == 'd' || rest[1] == 'D') &&
    590                           (rest[2] == 't' || rest[2] == 'T'))
    591                         zone = TT_EDT;
    592                   else if (zone == TT_UNKNOWN &&
    593                                    (rest[1] == 'e' || rest[1] == 'E') &&
    594                                    (rest[2] == 't' || rest[2] == 'T'))
    595                         zone = TT_EET;
    596                   else if (zone == TT_UNKNOWN &&
    597                                    (rest[1] == 's' || rest[1] == 'S') &&
    598                                    (rest[2] == 't' || rest[2] == 'T'))
    599                         zone = TT_EST;
    600                   break;
    601                 case 'f': case 'F':
    602                   if (month == TT_UNKNOWN &&
    603                           (rest[1] == 'e' || rest[1] == 'E') &&
    604                           (rest[2] == 'b' || rest[2] == 'B'))
    605                         month = TT_FEB;
    606                   else if (dotw == TT_UNKNOWN &&
    607                                    (rest[1] == 'r' || rest[1] == 'R') &&
    608                                    (rest[2] == 'i' || rest[2] == 'I'))
    609                         dotw = TT_FRI;
    610                   break;
    611                 case 'g': case 'G':
    612                   if (zone == TT_UNKNOWN &&
    613                           (rest[1] == 'm' || rest[1] == 'M') &&
    614                           (rest[2] == 't' || rest[2] == 'T'))
    615                         zone = TT_GMT;
    616                   break;
    617                 case 'j': case 'J':
    618                   if (month == TT_UNKNOWN &&
    619                           (rest[1] == 'a' || rest[1] == 'A') &&
    620                           (rest[2] == 'n' || rest[2] == 'N'))
    621                         month = TT_JAN;
    622                   else if (zone == TT_UNKNOWN &&
    623                                    (rest[1] == 's' || rest[1] == 'S') &&
    624                                    (rest[2] == 't' || rest[2] == 'T'))
    625                         zone = TT_JST;
    626                   else if (month == TT_UNKNOWN &&
    627                                    (rest[1] == 'u' || rest[1] == 'U') &&
    628                                    (rest[2] == 'l' || rest[2] == 'L'))
    629                         month = TT_JUL;
    630                   else if (month == TT_UNKNOWN &&
    631                                    (rest[1] == 'u' || rest[1] == 'U') &&
    632                                    (rest[2] == 'n' || rest[2] == 'N'))
    633                         month = TT_JUN;
    634                   break;
    635                 case 'm': case 'M':
    636                   if (month == TT_UNKNOWN &&
    637                           (rest[1] == 'a' || rest[1] == 'A') &&
    638                           (rest[2] == 'r' || rest[2] == 'R'))
    639                         month = TT_MAR;
    640                   else if (month == TT_UNKNOWN &&
    641                                    (rest[1] == 'a' || rest[1] == 'A') &&
    642                                    (rest[2] == 'y' || rest[2] == 'Y'))
    643                         month = TT_MAY;
    644                   else if (zone == TT_UNKNOWN &&
    645                                    (rest[1] == 'd' || rest[1] == 'D') &&
    646                                    (rest[2] == 't' || rest[2] == 'T'))
    647                         zone = TT_MDT;
    648                   else if (zone == TT_UNKNOWN &&
    649                                    (rest[1] == 'e' || rest[1] == 'E') &&
    650                                    (rest[2] == 't' || rest[2] == 'T'))
    651                         zone = TT_MET;
    652                   else if (dotw == TT_UNKNOWN &&
    653                                    (rest[1] == 'o' || rest[1] == 'O') &&
    654                                    (rest[2] == 'n' || rest[2] == 'N'))
    655                         dotw = TT_MON;
    656                   else if (zone == TT_UNKNOWN &&
    657                                    (rest[1] == 's' || rest[1] == 'S') &&
    658                                    (rest[2] == 't' || rest[2] == 'T'))
    659                         zone = TT_MST;
    660                   break;
    661                 case 'n': case 'N':
    662                   if (month == TT_UNKNOWN &&
    663                           (rest[1] == 'o' || rest[1] == 'O') &&
    664                           (rest[2] == 'v' || rest[2] == 'V'))
    665                         month = TT_NOV;
    666                   else if (zone == TT_UNKNOWN &&
    667                                    (rest[1] == 's' || rest[1] == 'S') &&
    668                                    (rest[2] == 't' || rest[2] == 'T'))
    669                         zone = TT_NST;
    670                   break;
    671                 case 'o': case 'O':
    672                   if (month == TT_UNKNOWN &&
    673                           (rest[1] == 'c' || rest[1] == 'C') &&
    674                           (rest[2] == 't' || rest[2] == 'T'))
    675                         month = TT_OCT;
    676                   break;
    677                 case 'p': case 'P':
    678                   if (zone == TT_UNKNOWN &&
    679                           (rest[1] == 'd' || rest[1] == 'D') &&
    680                           (rest[2] == 't' || rest[2] == 'T'))
    681                         zone = TT_PDT;
    682                   else if (zone == TT_UNKNOWN &&
    683                                    (rest[1] == 's' || rest[1] == 'S') &&
    684                                    (rest[2] == 't' || rest[2] == 'T'))
    685                         zone = TT_PST;
    686                   break;
    687                 case 's': case 'S':
    688                   if (dotw == TT_UNKNOWN &&
    689                           (rest[1] == 'a' || rest[1] == 'A') &&
    690                           (rest[2] == 't' || rest[2] == 'T'))
    691                         dotw = TT_SAT;
    692                   else if (month == TT_UNKNOWN &&
    693                                    (rest[1] == 'e' || rest[1] == 'E') &&
    694                                    (rest[2] == 'p' || rest[2] == 'P'))
    695                         month = TT_SEP;
    696                   else if (dotw == TT_UNKNOWN &&
    697                                    (rest[1] == 'u' || rest[1] == 'U') &&
    698                                    (rest[2] == 'n' || rest[2] == 'N'))
    699                         dotw = TT_SUN;
    700                   break;
    701                 case 't': case 'T':
    702                   if (dotw == TT_UNKNOWN &&
    703                           (rest[1] == 'h' || rest[1] == 'H') &&
    704                           (rest[2] == 'u' || rest[2] == 'U'))
    705                         dotw = TT_THU;
    706                   else if (dotw == TT_UNKNOWN &&
    707                                    (rest[1] == 'u' || rest[1] == 'U') &&
    708                                    (rest[2] == 'e' || rest[2] == 'E'))
    709                         dotw = TT_TUE;
    710                   break;
    711                 case 'u': case 'U':
    712                   if (zone == TT_UNKNOWN &&
    713                           (rest[1] == 't' || rest[1] == 'T') &&
    714                           !(rest[2] >= 'A' && rest[2] <= 'Z') &&
    715                           !(rest[2] >= 'a' && rest[2] <= 'z'))
    716                         /* UT is the same as GMT but UTx is not. */
    717                         zone = TT_GMT;
    718                   break;
    719                 case 'w': case 'W':
    720                   if (dotw == TT_UNKNOWN &&
    721                           (rest[1] == 'e' || rest[1] == 'E') &&
    722                           (rest[2] == 'd' || rest[2] == 'D'))
    723                         dotw = TT_WED;
    724                   break;
    725 
    726                 case '+': case '-':
    727                   {
    728                         const char *end;
    729                         int sign;
    730                         if (zone_offset != -1)
    731                           {
    732                                 /* already got one... */
    733                                 rest++;
    734                                 break;
    735                           }
    736                         if (zone != TT_UNKNOWN && zone != TT_GMT)
    737                           {
    738                                 /* GMT+0300 is legal, but PST+0300 is not. */
    739                                 rest++;
    740                                 break;
    741                           }
    742 
    743                         sign = ((*rest == '+') ? 1 : -1);
    744                         rest++; /* move over sign */
    745                         end = rest;
    746                         while (*end >= '0' && *end <= '9')
    747                           end++;
    748                         if (rest == end) /* no digits here */
    749                           break;
    750 
    751                         if ((end - rest) == 4)
    752                           /* offset in HHMM */
    753                           zone_offset = (((((rest[0]-'0')*10) + (rest[1]-'0')) * 60) +
    754                                                          (((rest[2]-'0')*10) + (rest[3]-'0')));
    755                         else if ((end - rest) == 2)
    756                           /* offset in hours */
    757                           zone_offset = (((rest[0]-'0')*10) + (rest[1]-'0')) * 60;
    758                         else if ((end - rest) == 1)
    759                           /* offset in hours */
    760                           zone_offset = (rest[0]-'0') * 60;
    761                         else
    762                           /* 3 or >4 */
    763                           break;
    764 
    765                         zone_offset *= sign;
    766                         zone = TT_GMT;
    767                         break;
    768                   }
    769 
    770                 case '0': case '1': case '2': case '3': case '4':
    771                 case '5': case '6': case '7': case '8': case '9':
    772                   {
    773                         int tmp_hour = -1;
    774                         int tmp_min = -1;
    775                         int tmp_sec = -1;
    776                         const char *end = rest + 1;
    777                         while (*end >= '0' && *end <= '9')
    778                           end++;
    779 
    780                         /* end is now the first character after a range of digits. */
    781 
    782                         if (*end == ':')
    783                           {
    784                                 if (hour >= 0 && min >= 0) /* already got it */
    785                                   break;
    786 
    787                                 /* We have seen "[0-9]+:", so this is probably HH:MM[:SS] */
    788                                 if ((end - rest) > 2)
    789                                   /* it is [0-9][0-9][0-9]+: */
    790                                   break;
    791                                 else if ((end - rest) == 2)
    792                                   tmp_hour = ((rest[0]-'0')*10 +
    793                                                           (rest[1]-'0'));
    794                                 else
    795                                   tmp_hour = (rest[0]-'0');
    796 
    797                                 /* move over the colon, and parse minutes */
    798 
    799                                 rest = ++end;
    800                                 while (*end >= '0' && *end <= '9')
    801                                   end++;
    802 
    803                                 if (end == rest)
    804                                   /* no digits after first colon? */
    805                                   break;
    806                                 else if ((end - rest) > 2)
    807                                   /* it is [0-9][0-9][0-9]+: */
    808                                   break;
    809                                 else if ((end - rest) == 2)
    810                                   tmp_min = ((rest[0]-'0')*10 +
    811                                                          (rest[1]-'0'));
    812                                 else
    813                                   tmp_min = (rest[0]-'0');
    814 
    815                                 /* now go for seconds */
    816                                 rest = end;
    817                                 if (*rest == ':')
    818                                   rest++;
    819                                 end = rest;
    820                                 while (*end >= '0' && *end <= '9')
    821                                   end++;
    822 
    823                                 if (end == rest)
    824                                   /* no digits after second colon - that's ok. */
    825                                   ;
    826                                 else if ((end - rest) > 2)
    827                                   /* it is [0-9][0-9][0-9]+: */
    828                                   break;
    829                                 else if ((end - rest) == 2)
    830                                   tmp_sec = ((rest[0]-'0')*10 +
    831                                                          (rest[1]-'0'));
    832                                 else
    833                                   tmp_sec = (rest[0]-'0');
    834 
    835                                 /* If we made it here, we've parsed hour and min,
    836                                    and possibly sec, so it worked as a unit. */
    837 
    838                                 /* skip over whitespace and see if there's an AM or PM
    839                                    directly following the time.
    840                                  */
    841                                 if (tmp_hour <= 12)
    842                                   {
    843                                         const char *s = end;
    844                                         while (*s && (*s == ' ' || *s == '\t'))
    845                                           s++;
    846                                         if ((s[0] == 'p' || s[0] == 'P') &&
    847                                                 (s[1] == 'm' || s[1] == 'M'))
    848                                           /* 10:05pm == 22:05, and 12:05pm == 12:05 */
    849                                           tmp_hour = (tmp_hour == 12 ? 12 : tmp_hour + 12);
    850                                         else if (tmp_hour == 12 &&
    851                                                          (s[0] == 'a' || s[0] == 'A') &&
    852                                                          (s[1] == 'm' || s[1] == 'M'))
    853                                           /* 12:05am == 00:05 */
    854                                           tmp_hour = 0;
    855                                   }
    856 
    857                                 hour = tmp_hour;
    858                                 min = tmp_min;
    859                                 sec = tmp_sec;
    860                                 rest = end;
    861                                 break;
    862                           }
    863                         else if ((*end == '/' || *end == '-') &&
    864                                          end[1] >= '0' && end[1] <= '9')
    865                           {
    866                                 /* Perhaps this is 6/16/95, 16/6/95, 6-16-95, or 16-6-95
    867                                    or even 95-06-05...
    868                                    #### But it doesn't handle 1995-06-22.
    869                                  */
    870                                 int n1, n2, n3;
    871                                 const char *s;
    872 
    873                                 if (month != TT_UNKNOWN)
    874                                   /* if we saw a month name, this can't be. */
    875                                   break;
    876 
    877                                 s = rest;
    878 
    879                                 n1 = (*s++ - '0');                                /* first 1 or 2 digits */
    880                                 if (*s >= '0' && *s <= '9')
    881                                   n1 = n1*10 + (*s++ - '0');
    882 
    883                                 if (*s != '/' && *s != '-')                /* slash */
    884                                   break;
    885                                 s++;
    886 
    887                                 if (*s < '0' || *s > '9')                /* second 1 or 2 digits */
    888                                   break;
    889                                 n2 = (*s++ - '0');
    890                                 if (*s >= '0' && *s <= '9')
    891                                   n2 = n2*10 + (*s++ - '0');
    892 
    893                                 if (*s != '/' && *s != '-')                /* slash */
    894                                   break;
    895                                 s++;
    896 
    897                                 if (*s < '0' || *s > '9')                /* third 1, 2, 4, or 5 digits */
    898                                   break;
    899                                 n3 = (*s++ - '0');
    900                                 if (*s >= '0' && *s <= '9')
    901                                   n3 = n3*10 + (*s++ - '0');
    902 
    903                                 if (*s >= '0' && *s <= '9')            /* optional digits 3, 4, and 5 */
    904                                   {
    905                                         n3 = n3*10 + (*s++ - '0');
    906                                         if (*s < '0' || *s > '9')
    907                                           break;
    908                                         n3 = n3*10 + (*s++ - '0');
    909                                         if (*s >= '0' && *s <= '9')
    910                                           n3 = n3*10 + (*s++ - '0');
    911                                   }
    912 
    913                                 if ((*s >= '0' && *s <= '9') ||        /* followed by non-alphanum */
    914                                         (*s >= 'A' && *s <= 'Z') ||
    915                                         (*s >= 'a' && *s <= 'z'))
    916                                   break;
    917 
    918                                 /* Ok, we parsed three 1-2 digit numbers, with / or -
    919                                    between them.  Now decide what the hell they are
    920                                    (DD/MM/YY or MM/DD/YY or YY/MM/DD.)
    921                                  */
    922 
    923                                 if (n1 > 31 || n1 == 0)  /* must be YY/MM/DD */
    924                                   {
    925                                         if (n2 > 12) break;
    926                                         if (n3 > 31) break;
    927                                         year = n1;
    928                                         if (year < 70)
    929                                             year += 2000;
    930                                         else if (year < 100)
    931                                             year += 1900;
    932                                         month = (TIME_TOKEN)(n2 + ((int)TT_JAN) - 1);
    933                                         date = n3;
    934                                         rest = s;
    935                                         break;
    936                                   }
    937 
    938                                 if (n1 > 12 && n2 > 12)  /* illegal */
    939                                   {
    940                                         rest = s;
    941                                         break;
    942                                   }
    943 
    944                                 if (n3 < 70)
    945                                     n3 += 2000;
    946                                 else if (n3 < 100)
    947                                     n3 += 1900;
    948 
    949                                 if (n1 > 12)  /* must be DD/MM/YY */
    950                                   {
    951                                         date = n1;
    952                                         month = (TIME_TOKEN)(n2 + ((int)TT_JAN) - 1);
    953                                         year = n3;
    954                                   }
    955                                 else                  /* assume MM/DD/YY */
    956                                   {
    957                                         /* #### In the ambiguous case, should we consult the
    958                                            locale to find out the local default? */
    959                                         month = (TIME_TOKEN)(n1 + ((int)TT_JAN) - 1);
    960                                         date = n2;
    961                                         year = n3;
    962                                   }
    963                                 rest = s;
    964                           }
    965                         else if ((*end >= 'A' && *end <= 'Z') ||
    966                                          (*end >= 'a' && *end <= 'z'))
    967                           /* Digits followed by non-punctuation - what's that? */
    968                           ;
    969                         else if ((end - rest) == 5)                /* five digits is a year */
    970                           year = (year < 0
    971                                           ? ((rest[0]-'0')*10000L +
    972                                                  (rest[1]-'0')*1000L +
    973                                                  (rest[2]-'0')*100L +
    974                                                  (rest[3]-'0')*10L +
    975                                                  (rest[4]-'0'))
    976                                           : year);
    977                         else if ((end - rest) == 4)                /* four digits is a year */
    978                           year = (year < 0
    979                                           ? ((rest[0]-'0')*1000L +
    980                                                  (rest[1]-'0')*100L +
    981                                                  (rest[2]-'0')*10L +
    982                                                  (rest[3]-'0'))
    983                                           : year);
    984                         else if ((end - rest) == 2)                /* two digits - date or year */
    985                           {
    986                                 int n = ((rest[0]-'0')*10 +
    987                                                  (rest[1]-'0'));
    988                                 /* If we don't have a date (day of the month) and we see a number
    989                                      less than 32, then assume that is the date.
    990 
    991                                          Otherwise, if we have a date and not a year, assume this is the
    992                                          year.  If it is less than 70, then assume it refers to the 21st
    993                                          century.  If it is two digits (>= 70), assume it refers to this
    994                                          century.  Otherwise, assume it refers to an unambiguous year.
    995 
    996                                          The world will surely end soon.
    997                                    */
    998                                 if (date < 0 && n < 32)
    999                                   date = n;
   1000                                 else if (year < 0)
   1001                                   {
   1002                                         if (n < 70)
   1003                                           year = 2000 + n;
   1004                                         else if (n < 100)
   1005                                           year = 1900 + n;
   1006                                         else
   1007                                           year = n;
   1008                                   }
   1009                                 /* else what the hell is this. */
   1010                           }
   1011                         else if ((end - rest) == 1)                /* one digit - date */
   1012                           date = (date < 0 ? (rest[0]-'0') : date);
   1013                         /* else, three or more than five digits - what's that? */
   1014 
   1015                         break;
   1016                   }
   1017                 }
   1018 
   1019           /* Skip to the end of this token, whether we parsed it or not.
   1020                  Tokens are delimited by whitespace, or ,;-/
   1021                  But explicitly not :+-.
   1022            */
   1023           while (*rest &&
   1024                          *rest != ' ' && *rest != '\t' &&
   1025                          *rest != ',' && *rest != ';' &&
   1026                          *rest != '-' && *rest != '+' &&
   1027                          *rest != '/' &&
   1028                          *rest != '(' && *rest != ')' && *rest != '[' && *rest != ']')
   1029                 rest++;
   1030           /* skip over uninteresting chars. */
   1031         SKIP_MORE:
   1032           while (*rest &&
   1033                          (*rest == ' ' || *rest == '\t' ||
   1034                           *rest == ',' || *rest == ';' || *rest == '/' ||
   1035                           *rest == '(' || *rest == ')' || *rest == '[' || *rest == ']'))
   1036                 rest++;
   1037 
   1038           /* "-" is ignored at the beginning of a token if we have not yet
   1039                  parsed a year (e.g., the second "-" in "30-AUG-1966"), or if
   1040                  the character after the dash is not a digit. */
   1041           if (*rest == '-' && ((rest > string && isalpha(rest[-1]) && year < 0)
   1042               || rest[1] < '0' || rest[1] > '9'))
   1043                 {
   1044                   rest++;
   1045                   goto SKIP_MORE;
   1046                 }
   1047 
   1048         }
   1049 
   1050   if (zone != TT_UNKNOWN && zone_offset == -1)
   1051         {
   1052           switch (zone)
   1053                 {
   1054                 case TT_PST: zone_offset = -8 * 60; break;
   1055                 case TT_PDT: zone_offset = -8 * 60; dst_offset = 1 * 60; break;
   1056                 case TT_MST: zone_offset = -7 * 60; break;
   1057                 case TT_MDT: zone_offset = -7 * 60; dst_offset = 1 * 60; break;
   1058                 case TT_CST: zone_offset = -6 * 60; break;
   1059                 case TT_CDT: zone_offset = -6 * 60; dst_offset = 1 * 60; break;
   1060                 case TT_EST: zone_offset = -5 * 60; break;
   1061                 case TT_EDT: zone_offset = -5 * 60; dst_offset = 1 * 60; break;
   1062                 case TT_AST: zone_offset = -4 * 60; break;
   1063                 case TT_NST: zone_offset = -3 * 60 - 30; break;
   1064                 case TT_GMT: zone_offset =  0 * 60; break;
   1065                 case TT_BST: zone_offset =  0 * 60; dst_offset = 1 * 60; break;
   1066                 case TT_MET: zone_offset =  1 * 60; break;
   1067                 case TT_EET: zone_offset =  2 * 60; break;
   1068                 case TT_JST: zone_offset =  9 * 60; break;
   1069                 default:
   1070                   PR_ASSERT (0);
   1071                   break;
   1072                 }
   1073         }
   1074 
   1075   /* If we didn't find a year, month, or day-of-the-month, we can't
   1076          possibly parse this, and in fact, mktime() will do something random
   1077          (I'm seeing it return "Tue Feb  5 06:28:16 2036", which is no doubt
   1078          a numerologically significant date... */
   1079   if (month == TT_UNKNOWN || date == -1 || year == -1 || year > PR_INT16_MAX)
   1080       return PR_FAILURE;
   1081 
   1082   memset(result, 0, sizeof(*result));
   1083   if (sec != -1)
   1084         result->tm_sec = sec;
   1085   if (min != -1)
   1086         result->tm_min = min;
   1087   if (hour != -1)
   1088         result->tm_hour = hour;
   1089   if (date != -1)
   1090         result->tm_mday = date;
   1091   if (month != TT_UNKNOWN)
   1092         result->tm_month = (((int)month) - ((int)TT_JAN));
   1093   if (year != -1)
   1094         result->tm_year = year;
   1095   if (dotw != TT_UNKNOWN)
   1096         result->tm_wday = (((int)dotw) - ((int)TT_SUN));
   1097   /*
   1098    * Mainly to compute wday and yday, but normalized time is also required
   1099    * by the check below that works around a Visual C++ 2005 mktime problem.
   1100    */
   1101   PR_NormalizeTime(result, PR_GMTParameters);
   1102   /* The remaining work is to set the gmt and dst offsets in tm_params. */
   1103 
   1104   if (zone == TT_UNKNOWN && default_to_gmt)
   1105         {
   1106           /* No zone was specified, so pretend the zone was GMT. */
   1107           zone = TT_GMT;
   1108           zone_offset = 0;
   1109         }
   1110 
   1111   if (zone_offset == -1)
   1112          {
   1113            /* no zone was specified, and we're to assume that everything
   1114              is local. */
   1115           struct tm localTime;
   1116           time_t secs;
   1117 
   1118           PR_ASSERT(result->tm_month > -1 &&
   1119                     result->tm_mday > 0 &&
   1120                     result->tm_hour > -1 &&
   1121                     result->tm_min > -1 &&
   1122                     result->tm_sec > -1);
   1123 
   1124             /*
   1125              * To obtain time_t from a tm structure representing the local
   1126              * time, we call mktime().  However, we need to see if we are
   1127              * on 1-Jan-1970 or before.  If we are, we can't call mktime()
   1128              * because mktime() will crash on win16. In that case, we
   1129              * calculate zone_offset based on the zone offset at
   1130              * 00:00:00, 2 Jan 1970 GMT, and subtract zone_offset from the
   1131              * date we are parsing to transform the date to GMT.  We also
   1132              * do so if mktime() returns (time_t) -1 (time out of range).
   1133            */
   1134 
   1135           /* month, day, hours, mins and secs are always non-negative
   1136              so we dont need to worry about them. */
   1137           if(result->tm_year >= 1970)
   1138                 {
   1139                   PRInt64 usec_per_sec;
   1140 
   1141                   localTime.tm_sec = result->tm_sec;
   1142                   localTime.tm_min = result->tm_min;
   1143                   localTime.tm_hour = result->tm_hour;
   1144                   localTime.tm_mday = result->tm_mday;
   1145                   localTime.tm_mon = result->tm_month;
   1146                   localTime.tm_year = result->tm_year - 1900;
   1147                   /* Set this to -1 to tell mktime "I don't care".  If you set
   1148                      it to 0 or 1, you are making assertions about whether the
   1149                      date you are handing it is in daylight savings mode or not;
   1150                      and if you're wrong, it will "fix" it for you. */
   1151                   localTime.tm_isdst = -1;
   1152 
   1153 #if _MSC_VER == 1400  /* 1400 = Visual C++ 2005 (8.0) */
   1154                   /*
   1155                    * mktime will return (time_t) -1 if the input is a date
   1156                    * after 23:59:59, December 31, 3000, US Pacific Time (not
   1157                    * UTC as documented):
   1158                    * http://msdn.microsoft.com/en-us/library/d1y53h2a(VS.80).aspx
   1159                    * But if the year is 3001, mktime also invokes the invalid
   1160                    * parameter handler, causing the application to crash.  This
   1161                    * problem has been reported in
   1162                    * http://connect.microsoft.com/VisualStudio/feedback/ViewFeedback.aspx?FeedbackID=266036.
   1163                    * We avoid this crash by not calling mktime if the date is
   1164                    * out of range.  To use a simple test that works in any time
   1165                    * zone, we consider year 3000 out of range as well.  (See
   1166                    * bug 480740.)
   1167                    */
   1168                   if (result->tm_year >= 3000) {
   1169                       /* Emulate what mktime would have done. */
   1170                       errno = EINVAL;
   1171                       secs = (time_t) -1;
   1172                   } else {
   1173                       secs = mktime(&localTime);
   1174                   }
   1175 #else
   1176                   secs = mktime(&localTime);
   1177 #endif
   1178                   if (secs != (time_t) -1)
   1179                     {
   1180                       PRTime usecs64;
   1181                       LL_I2L(usecs64, secs);
   1182                       LL_I2L(usec_per_sec, PR_USEC_PER_SEC);
   1183                       LL_MUL(usecs64, usecs64, usec_per_sec);
   1184                       *result_imploded = usecs64;
   1185                       return PR_SUCCESS;
   1186                     }
   1187                 }
   1188 
   1189                 /* So mktime() can't handle this case.  We assume the
   1190                    zone_offset for the date we are parsing is the same as
   1191                    the zone offset on 00:00:00 2 Jan 1970 GMT. */
   1192                 secs = 86400;
   1193                 localtime_r(&secs, &localTime);
   1194                 zone_offset = localTime.tm_min
   1195                               + 60 * localTime.tm_hour
   1196                               + 1440 * (localTime.tm_mday - 2);
   1197         }
   1198 
   1199   result->tm_params.tp_gmt_offset = zone_offset * 60;
   1200   result->tm_params.tp_dst_offset = dst_offset * 60;
   1201 
   1202   *result_imploded = PR_ImplodeTime(result);
   1203   return PR_SUCCESS;
   1204 }
   1205