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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  * Unit tests are in base/time/pr_time_unittest.cc.
66  */
67 
68 #include "base/logging.h"
69 #include "base/third_party/nspr/prtime.h"
70 #include "build/build_config.h"
71 
72 #if defined(OS_WIN)
73 #include <windows.h>
74 #elif defined(OS_MACOSX)
75 #include <CoreFoundation/CoreFoundation.h>
76 #elif defined(OS_ANDROID)
77 #include <ctype.h>
78 #include "base/os_compat_android.h"  // For timegm()
79 #elif defined(OS_NACL)
80 #include "base/os_compat_nacl.h"  // For timegm()
81 #endif
82 #include <errno.h>  /* for EINVAL */
83 #include <time.h>
84 
85 /* Implements the Unix localtime_r() function for windows */
86 #if defined(OS_WIN)
localtime_r(const time_t * secs,struct tm * time)87 static void localtime_r(const time_t* secs, struct tm* time) {
88   (void) localtime_s(time, secs);
89 }
90 #endif
91 
92 /*
93  *------------------------------------------------------------------------
94  *
95  * PR_ImplodeTime --
96  *
97  *     Cf. time_t mktime(struct tm *tp)
98  *     Note that 1 year has < 2^25 seconds.  So an PRInt32 is large enough.
99  *
100  *------------------------------------------------------------------------
101  */
102 PRTime
PR_ImplodeTime(const PRExplodedTime * exploded)103 PR_ImplodeTime(const PRExplodedTime *exploded)
104 {
105     // This is important, we want to make sure multiplications are
106     // done with the correct precision.
107     static const PRTime kSecondsToMicroseconds = static_cast<PRTime>(1000000);
108 #if defined(OS_WIN)
109    // Create the system struct representing our exploded time.
110     SYSTEMTIME st = {0};
111     FILETIME ft = {0};
112     ULARGE_INTEGER uli = {0};
113 
114     st.wYear = exploded->tm_year;
115     st.wMonth = exploded->tm_month + 1;
116     st.wDayOfWeek = exploded->tm_wday;
117     st.wDay = exploded->tm_mday;
118     st.wHour = exploded->tm_hour;
119     st.wMinute = exploded->tm_min;
120     st.wSecond = exploded->tm_sec;
121     st.wMilliseconds = exploded->tm_usec/1000;
122      // Convert to FILETIME.
123     if (!SystemTimeToFileTime(&st, &ft)) {
124       NOTREACHED() << "Unable to convert time";
125       return 0;
126     }
127     // Apply offsets.
128     uli.LowPart = ft.dwLowDateTime;
129     uli.HighPart = ft.dwHighDateTime;
130     // Convert from Windows epoch to NSPR epoch, and 100-nanoseconds units
131     // to microsecond units.
132     PRTime result =
133         static_cast<PRTime>((uli.QuadPart / 10) - 11644473600000000i64);
134     // Adjust for time zone and dst.  Convert from seconds to microseconds.
135     result -= (exploded->tm_params.tp_gmt_offset +
136                exploded->tm_params.tp_dst_offset) * kSecondsToMicroseconds;
137     // Add microseconds that cannot be represented in |st|.
138     result += exploded->tm_usec % 1000;
139     return result;
140 #elif defined(OS_MACOSX)
141     // Create the system struct representing our exploded time.
142     CFGregorianDate gregorian_date;
143     gregorian_date.year = exploded->tm_year;
144     gregorian_date.month = exploded->tm_month + 1;
145     gregorian_date.day = exploded->tm_mday;
146     gregorian_date.hour = exploded->tm_hour;
147     gregorian_date.minute = exploded->tm_min;
148     gregorian_date.second = exploded->tm_sec;
149 
150     // Compute |absolute_time| in seconds, correct for gmt and dst
151     // (note the combined offset will be negative when we need to add it), then
152     // convert to microseconds which is what PRTime expects.
153     CFAbsoluteTime absolute_time =
154         CFGregorianDateGetAbsoluteTime(gregorian_date, NULL);
155     PRTime result = static_cast<PRTime>(absolute_time);
156     result -= exploded->tm_params.tp_gmt_offset +
157               exploded->tm_params.tp_dst_offset;
158     result += kCFAbsoluteTimeIntervalSince1970;  // PRTime epoch is 1970
159     result *= kSecondsToMicroseconds;
160     result += exploded->tm_usec;
161     return result;
162 #elif defined(OS_POSIX)
163     struct tm exp_tm = {0};
164     exp_tm.tm_sec  = exploded->tm_sec;
165     exp_tm.tm_min  = exploded->tm_min;
166     exp_tm.tm_hour = exploded->tm_hour;
167     exp_tm.tm_mday = exploded->tm_mday;
168     exp_tm.tm_mon  = exploded->tm_month;
169     exp_tm.tm_year = exploded->tm_year - 1900;
170 
171     time_t absolute_time = timegm(&exp_tm);
172 
173     // If timegm returned -1.  Since we don't pass it a time zone, the only
174     // valid case of returning -1 is 1 second before Epoch (Dec 31, 1969).
175     if (absolute_time == -1 &&
176         !(exploded->tm_year == 1969 && exploded->tm_month == 11 &&
177         exploded->tm_mday == 31 && exploded->tm_hour == 23 &&
178         exploded->tm_min == 59 && exploded->tm_sec == 59)) {
179       // If we get here, time_t must be 32 bits.
180       // Date was possibly too far in the future and would overflow.  Return
181       // the most future date possible (year 2038).
182       if (exploded->tm_year >= 1970)
183         return INT_MAX * kSecondsToMicroseconds;
184       // Date was possibly too far in the past and would underflow.  Return
185       // the most past date possible (year 1901).
186       return INT_MIN * kSecondsToMicroseconds;
187     }
188 
189     PRTime result = static_cast<PRTime>(absolute_time);
190     result -= exploded->tm_params.tp_gmt_offset +
191               exploded->tm_params.tp_dst_offset;
192     result *= kSecondsToMicroseconds;
193     result += exploded->tm_usec;
194     return result;
195 #else
196 #error No PR_ImplodeTime implemented on your platform.
197 #endif
198 }
199 
200 /*
201  * The COUNT_LEAPS macro counts the number of leap years passed by
202  * till the start of the given year Y.  At the start of the year 4
203  * A.D. the number of leap years passed by is 0, while at the start of
204  * the year 5 A.D. this count is 1. The number of years divisible by
205  * 100 but not divisible by 400 (the non-leap years) is deducted from
206  * the count to get the correct number of leap years.
207  *
208  * The COUNT_DAYS macro counts the number of days since 01/01/01 till the
209  * start of the given year Y. The number of days at the start of the year
210  * 1 is 0 while the number of days at the start of the year 2 is 365
211  * (which is ((2)-1) * 365) and so on. The reference point is 01/01/01
212  * midnight 00:00:00.
213  */
214 
215 #define COUNT_LEAPS(Y)   ( ((Y)-1)/4 - ((Y)-1)/100 + ((Y)-1)/400 )
216 #define COUNT_DAYS(Y)  ( ((Y)-1)*365 + COUNT_LEAPS(Y) )
217 #define DAYS_BETWEEN_YEARS(A, B)  (COUNT_DAYS(B) - COUNT_DAYS(A))
218 
219 /*
220  * Static variables used by functions in this file
221  */
222 
223 /*
224  * The following array contains the day of year for the last day of
225  * each month, where index 1 is January, and day 0 is January 1.
226  */
227 
228 static const int lastDayOfMonth[2][13] = {
229     {-1, 30, 58, 89, 119, 150, 180, 211, 242, 272, 303, 333, 364},
230     {-1, 30, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365}
231 };
232 
233 /*
234  * The number of days in a month
235  */
236 
237 static const PRInt8 nDays[2][12] = {
238     {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31},
239     {31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}
240 };
241 
242 /*
243  *-------------------------------------------------------------------------
244  *
245  * IsLeapYear --
246  *
247  *     Returns 1 if the year is a leap year, 0 otherwise.
248  *
249  *-------------------------------------------------------------------------
250  */
251 
IsLeapYear(PRInt16 year)252 static int IsLeapYear(PRInt16 year)
253 {
254     if ((year % 4 == 0 && year % 100 != 0) || year % 400 == 0)
255         return 1;
256     else
257         return 0;
258 }
259 
260 /*
261  * 'secOffset' should be less than 86400 (i.e., a day).
262  * 'time' should point to a normalized PRExplodedTime.
263  */
264 
265 static void
ApplySecOffset(PRExplodedTime * time,PRInt32 secOffset)266 ApplySecOffset(PRExplodedTime *time, PRInt32 secOffset)
267 {
268     time->tm_sec += secOffset;
269 
270     /* Note that in this implementation we do not count leap seconds */
271     if (time->tm_sec < 0 || time->tm_sec >= 60) {
272         time->tm_min += time->tm_sec / 60;
273         time->tm_sec %= 60;
274         if (time->tm_sec < 0) {
275             time->tm_sec += 60;
276             time->tm_min--;
277         }
278     }
279 
280     if (time->tm_min < 0 || time->tm_min >= 60) {
281         time->tm_hour += time->tm_min / 60;
282         time->tm_min %= 60;
283         if (time->tm_min < 0) {
284             time->tm_min += 60;
285             time->tm_hour--;
286         }
287     }
288 
289     if (time->tm_hour < 0) {
290         /* Decrement mday, yday, and wday */
291         time->tm_hour += 24;
292         time->tm_mday--;
293         time->tm_yday--;
294         if (time->tm_mday < 1) {
295             time->tm_month--;
296             if (time->tm_month < 0) {
297                 time->tm_month = 11;
298                 time->tm_year--;
299                 if (IsLeapYear(time->tm_year))
300                     time->tm_yday = 365;
301                 else
302                     time->tm_yday = 364;
303             }
304             time->tm_mday = nDays[IsLeapYear(time->tm_year)][time->tm_month];
305         }
306         time->tm_wday--;
307         if (time->tm_wday < 0)
308             time->tm_wday = 6;
309     } else if (time->tm_hour > 23) {
310         /* Increment mday, yday, and wday */
311         time->tm_hour -= 24;
312         time->tm_mday++;
313         time->tm_yday++;
314         if (time->tm_mday >
315                 nDays[IsLeapYear(time->tm_year)][time->tm_month]) {
316             time->tm_mday = 1;
317             time->tm_month++;
318             if (time->tm_month > 11) {
319                 time->tm_month = 0;
320                 time->tm_year++;
321                 time->tm_yday = 0;
322             }
323         }
324         time->tm_wday++;
325         if (time->tm_wday > 6)
326             time->tm_wday = 0;
327     }
328 }
329 
330 void
PR_NormalizeTime(PRExplodedTime * time,PRTimeParamFn params)331 PR_NormalizeTime(PRExplodedTime *time, PRTimeParamFn params)
332 {
333     int daysInMonth;
334     PRInt32 numDays;
335 
336     /* Get back to GMT */
337     time->tm_sec -= time->tm_params.tp_gmt_offset
338             + time->tm_params.tp_dst_offset;
339     time->tm_params.tp_gmt_offset = 0;
340     time->tm_params.tp_dst_offset = 0;
341 
342     /* Now normalize GMT */
343 
344     if (time->tm_usec < 0 || time->tm_usec >= 1000000) {
345         time->tm_sec +=  time->tm_usec / 1000000;
346         time->tm_usec %= 1000000;
347         if (time->tm_usec < 0) {
348             time->tm_usec += 1000000;
349             time->tm_sec--;
350         }
351     }
352 
353     /* Note that we do not count leap seconds in this implementation */
354     if (time->tm_sec < 0 || time->tm_sec >= 60) {
355         time->tm_min += time->tm_sec / 60;
356         time->tm_sec %= 60;
357         if (time->tm_sec < 0) {
358             time->tm_sec += 60;
359             time->tm_min--;
360         }
361     }
362 
363     if (time->tm_min < 0 || time->tm_min >= 60) {
364         time->tm_hour += time->tm_min / 60;
365         time->tm_min %= 60;
366         if (time->tm_min < 0) {
367             time->tm_min += 60;
368             time->tm_hour--;
369         }
370     }
371 
372     if (time->tm_hour < 0 || time->tm_hour >= 24) {
373         time->tm_mday += time->tm_hour / 24;
374         time->tm_hour %= 24;
375         if (time->tm_hour < 0) {
376             time->tm_hour += 24;
377             time->tm_mday--;
378         }
379     }
380 
381     /* Normalize month and year before mday */
382     if (time->tm_month < 0 || time->tm_month >= 12) {
383         time->tm_year += time->tm_month / 12;
384         time->tm_month %= 12;
385         if (time->tm_month < 0) {
386             time->tm_month += 12;
387             time->tm_year--;
388         }
389     }
390 
391     /* Now that month and year are in proper range, normalize mday */
392 
393     if (time->tm_mday < 1) {
394         /* mday too small */
395         do {
396             /* the previous month */
397             time->tm_month--;
398             if (time->tm_month < 0) {
399                 time->tm_month = 11;
400                 time->tm_year--;
401             }
402             time->tm_mday += nDays[IsLeapYear(time->tm_year)][time->tm_month];
403         } while (time->tm_mday < 1);
404     } else {
405         daysInMonth = nDays[IsLeapYear(time->tm_year)][time->tm_month];
406         while (time->tm_mday > daysInMonth) {
407             /* mday too large */
408             time->tm_mday -= daysInMonth;
409             time->tm_month++;
410             if (time->tm_month > 11) {
411                 time->tm_month = 0;
412                 time->tm_year++;
413             }
414             daysInMonth = nDays[IsLeapYear(time->tm_year)][time->tm_month];
415         }
416     }
417 
418     /* Recompute yday and wday */
419     time->tm_yday = time->tm_mday +
420             lastDayOfMonth[IsLeapYear(time->tm_year)][time->tm_month];
421 
422     numDays = DAYS_BETWEEN_YEARS(1970, time->tm_year) + time->tm_yday;
423     time->tm_wday = (numDays + 4) % 7;
424     if (time->tm_wday < 0) {
425         time->tm_wday += 7;
426     }
427 
428     /* Recompute time parameters */
429 
430     time->tm_params = params(time);
431 
432     ApplySecOffset(time, time->tm_params.tp_gmt_offset
433             + time->tm_params.tp_dst_offset);
434 }
435 
436 /*
437  *------------------------------------------------------------------------
438  *
439  * PR_GMTParameters --
440  *
441  *     Returns the PRTimeParameters for Greenwich Mean Time.
442  *     Trivially, both the tp_gmt_offset and tp_dst_offset fields are 0.
443  *
444  *------------------------------------------------------------------------
445  */
446 
447 PRTimeParameters
PR_GMTParameters(const PRExplodedTime * gmt)448 PR_GMTParameters(const PRExplodedTime *gmt)
449 {
450     PRTimeParameters retVal = { 0, 0 };
451     return retVal;
452 }
453 
454 /*
455  * The following code implements PR_ParseTimeString().  It is based on
456  * ns/lib/xp/xp_time.c, revision 1.25, by Jamie Zawinski <jwz@netscape.com>.
457  */
458 
459 /*
460  * We only recognize the abbreviations of a small subset of time zones
461  * in North America, Europe, and Japan.
462  *
463  * PST/PDT: Pacific Standard/Daylight Time
464  * MST/MDT: Mountain Standard/Daylight Time
465  * CST/CDT: Central Standard/Daylight Time
466  * EST/EDT: Eastern Standard/Daylight Time
467  * AST: Atlantic Standard Time
468  * NST: Newfoundland Standard Time
469  * GMT: Greenwich Mean Time
470  * BST: British Summer Time
471  * MET: Middle Europe Time
472  * EET: Eastern Europe Time
473  * JST: Japan Standard Time
474  */
475 
476 typedef enum
477 {
478   TT_UNKNOWN,
479 
480   TT_SUN, TT_MON, TT_TUE, TT_WED, TT_THU, TT_FRI, TT_SAT,
481 
482   TT_JAN, TT_FEB, TT_MAR, TT_APR, TT_MAY, TT_JUN,
483   TT_JUL, TT_AUG, TT_SEP, TT_OCT, TT_NOV, TT_DEC,
484 
485   TT_PST, TT_PDT, TT_MST, TT_MDT, TT_CST, TT_CDT, TT_EST, TT_EDT,
486   TT_AST, TT_NST, TT_GMT, TT_BST, TT_MET, TT_EET, TT_JST
487 } TIME_TOKEN;
488 
489 /*
490  * This parses a time/date string into a PRTime
491  * (microseconds after "1-Jan-1970 00:00:00 GMT").
492  * It returns PR_SUCCESS on success, and PR_FAILURE
493  * if the time/date string can't be parsed.
494  *
495  * Many formats are handled, including:
496  *
497  *   14 Apr 89 03:20:12
498  *   14 Apr 89 03:20 GMT
499  *   Fri, 17 Mar 89 4:01:33
500  *   Fri, 17 Mar 89 4:01 GMT
501  *   Mon Jan 16 16:12 PDT 1989
502  *   Mon Jan 16 16:12 +0130 1989
503  *   6 May 1992 16:41-JST (Wednesday)
504  *   22-AUG-1993 10:59:12.82
505  *   22-AUG-1993 10:59pm
506  *   22-AUG-1993 12:59am
507  *   22-AUG-1993 12:59 PM
508  *   Friday, August 04, 1995 3:54 PM
509  *   06/21/95 04:24:34 PM
510  *   20/06/95 21:07
511  *   95-06-08 19:32:48 EDT
512  *   1995-06-17T23:11:25.342156Z
513  *
514  * If the input string doesn't contain a description of the timezone,
515  * we consult the `default_to_gmt' to decide whether the string should
516  * be interpreted relative to the local time zone (PR_FALSE) or GMT (PR_TRUE).
517  * The correct value for this argument depends on what standard specified
518  * the time string which you are parsing.
519  */
520 
521 PRStatus
PR_ParseTimeString(const char * string,PRBool default_to_gmt,PRTime * result_imploded)522 PR_ParseTimeString(
523         const char *string,
524         PRBool default_to_gmt,
525         PRTime *result_imploded)
526 {
527   PRExplodedTime tm;
528   PRExplodedTime *result = &tm;
529   TIME_TOKEN dotw = TT_UNKNOWN;
530   TIME_TOKEN month = TT_UNKNOWN;
531   TIME_TOKEN zone = TT_UNKNOWN;
532   int zone_offset = -1;
533   int dst_offset = 0;
534   int date = -1;
535   PRInt32 year = -1;
536   int hour = -1;
537   int min = -1;
538   int sec = -1;
539   int usec = -1;
540 
541   const char *rest = string;
542 
543   int iterations = 0;
544 
545   PR_ASSERT(string && result);
546   if (!string || !result) return PR_FAILURE;
547 
548   while (*rest)
549         {
550 
551           if (iterations++ > 1000)
552                 {
553                   return PR_FAILURE;
554                 }
555 
556           switch (*rest)
557                 {
558                 case 'a': case 'A':
559                   if (month == TT_UNKNOWN &&
560                           (rest[1] == 'p' || rest[1] == 'P') &&
561                           (rest[2] == 'r' || rest[2] == 'R'))
562                         month = TT_APR;
563                   else if (zone == TT_UNKNOWN &&
564                                    (rest[1] == 's' || rest[1] == 'S') &&
565                                    (rest[2] == 't' || rest[2] == 'T'))
566                         zone = TT_AST;
567                   else if (month == TT_UNKNOWN &&
568                                    (rest[1] == 'u' || rest[1] == 'U') &&
569                                    (rest[2] == 'g' || rest[2] == 'G'))
570                         month = TT_AUG;
571                   break;
572                 case 'b': case 'B':
573                   if (zone == TT_UNKNOWN &&
574                           (rest[1] == 's' || rest[1] == 'S') &&
575                           (rest[2] == 't' || rest[2] == 'T'))
576                         zone = TT_BST;
577                   break;
578                 case 'c': case 'C':
579                   if (zone == TT_UNKNOWN &&
580                           (rest[1] == 'd' || rest[1] == 'D') &&
581                           (rest[2] == 't' || rest[2] == 'T'))
582                         zone = TT_CDT;
583                   else if (zone == TT_UNKNOWN &&
584                                    (rest[1] == 's' || rest[1] == 'S') &&
585                                    (rest[2] == 't' || rest[2] == 'T'))
586                         zone = TT_CST;
587                   break;
588                 case 'd': case 'D':
589                   if (month == TT_UNKNOWN &&
590                           (rest[1] == 'e' || rest[1] == 'E') &&
591                           (rest[2] == 'c' || rest[2] == 'C'))
592                         month = TT_DEC;
593                   break;
594                 case 'e': case 'E':
595                   if (zone == TT_UNKNOWN &&
596                           (rest[1] == 'd' || rest[1] == 'D') &&
597                           (rest[2] == 't' || rest[2] == 'T'))
598                         zone = TT_EDT;
599                   else if (zone == TT_UNKNOWN &&
600                                    (rest[1] == 'e' || rest[1] == 'E') &&
601                                    (rest[2] == 't' || rest[2] == 'T'))
602                         zone = TT_EET;
603                   else if (zone == TT_UNKNOWN &&
604                                    (rest[1] == 's' || rest[1] == 'S') &&
605                                    (rest[2] == 't' || rest[2] == 'T'))
606                         zone = TT_EST;
607                   break;
608                 case 'f': case 'F':
609                   if (month == TT_UNKNOWN &&
610                           (rest[1] == 'e' || rest[1] == 'E') &&
611                           (rest[2] == 'b' || rest[2] == 'B'))
612                         month = TT_FEB;
613                   else if (dotw == TT_UNKNOWN &&
614                                    (rest[1] == 'r' || rest[1] == 'R') &&
615                                    (rest[2] == 'i' || rest[2] == 'I'))
616                         dotw = TT_FRI;
617                   break;
618                 case 'g': case 'G':
619                   if (zone == TT_UNKNOWN &&
620                           (rest[1] == 'm' || rest[1] == 'M') &&
621                           (rest[2] == 't' || rest[2] == 'T'))
622                         zone = TT_GMT;
623                   break;
624                 case 'j': case 'J':
625                   if (month == TT_UNKNOWN &&
626                           (rest[1] == 'a' || rest[1] == 'A') &&
627                           (rest[2] == 'n' || rest[2] == 'N'))
628                         month = TT_JAN;
629                   else if (zone == TT_UNKNOWN &&
630                                    (rest[1] == 's' || rest[1] == 'S') &&
631                                    (rest[2] == 't' || rest[2] == 'T'))
632                         zone = TT_JST;
633                   else if (month == TT_UNKNOWN &&
634                                    (rest[1] == 'u' || rest[1] == 'U') &&
635                                    (rest[2] == 'l' || rest[2] == 'L'))
636                         month = TT_JUL;
637                   else if (month == TT_UNKNOWN &&
638                                    (rest[1] == 'u' || rest[1] == 'U') &&
639                                    (rest[2] == 'n' || rest[2] == 'N'))
640                         month = TT_JUN;
641                   break;
642                 case 'm': case 'M':
643                   if (month == TT_UNKNOWN &&
644                           (rest[1] == 'a' || rest[1] == 'A') &&
645                           (rest[2] == 'r' || rest[2] == 'R'))
646                         month = TT_MAR;
647                   else if (month == TT_UNKNOWN &&
648                                    (rest[1] == 'a' || rest[1] == 'A') &&
649                                    (rest[2] == 'y' || rest[2] == 'Y'))
650                         month = TT_MAY;
651                   else if (zone == TT_UNKNOWN &&
652                                    (rest[1] == 'd' || rest[1] == 'D') &&
653                                    (rest[2] == 't' || rest[2] == 'T'))
654                         zone = TT_MDT;
655                   else if (zone == TT_UNKNOWN &&
656                                    (rest[1] == 'e' || rest[1] == 'E') &&
657                                    (rest[2] == 't' || rest[2] == 'T'))
658                         zone = TT_MET;
659                   else if (dotw == TT_UNKNOWN &&
660                                    (rest[1] == 'o' || rest[1] == 'O') &&
661                                    (rest[2] == 'n' || rest[2] == 'N'))
662                         dotw = TT_MON;
663                   else if (zone == TT_UNKNOWN &&
664                                    (rest[1] == 's' || rest[1] == 'S') &&
665                                    (rest[2] == 't' || rest[2] == 'T'))
666                         zone = TT_MST;
667                   break;
668                 case 'n': case 'N':
669                   if (month == TT_UNKNOWN &&
670                           (rest[1] == 'o' || rest[1] == 'O') &&
671                           (rest[2] == 'v' || rest[2] == 'V'))
672                         month = TT_NOV;
673                   else if (zone == TT_UNKNOWN &&
674                                    (rest[1] == 's' || rest[1] == 'S') &&
675                                    (rest[2] == 't' || rest[2] == 'T'))
676                         zone = TT_NST;
677                   break;
678                 case 'o': case 'O':
679                   if (month == TT_UNKNOWN &&
680                           (rest[1] == 'c' || rest[1] == 'C') &&
681                           (rest[2] == 't' || rest[2] == 'T'))
682                         month = TT_OCT;
683                   break;
684                 case 'p': case 'P':
685                   if (zone == TT_UNKNOWN &&
686                           (rest[1] == 'd' || rest[1] == 'D') &&
687                           (rest[2] == 't' || rest[2] == 'T'))
688                         zone = TT_PDT;
689                   else if (zone == TT_UNKNOWN &&
690                                    (rest[1] == 's' || rest[1] == 'S') &&
691                                    (rest[2] == 't' || rest[2] == 'T'))
692                         zone = TT_PST;
693                   break;
694                 case 's': case 'S':
695                   if (dotw == TT_UNKNOWN &&
696                           (rest[1] == 'a' || rest[1] == 'A') &&
697                           (rest[2] == 't' || rest[2] == 'T'))
698                         dotw = TT_SAT;
699                   else if (month == TT_UNKNOWN &&
700                                    (rest[1] == 'e' || rest[1] == 'E') &&
701                                    (rest[2] == 'p' || rest[2] == 'P'))
702                         month = TT_SEP;
703                   else if (dotw == TT_UNKNOWN &&
704                                    (rest[1] == 'u' || rest[1] == 'U') &&
705                                    (rest[2] == 'n' || rest[2] == 'N'))
706                         dotw = TT_SUN;
707                   break;
708                 case 't': case 'T':
709                   if (dotw == TT_UNKNOWN &&
710                           (rest[1] == 'h' || rest[1] == 'H') &&
711                           (rest[2] == 'u' || rest[2] == 'U'))
712                         dotw = TT_THU;
713                   else if (dotw == TT_UNKNOWN &&
714                                    (rest[1] == 'u' || rest[1] == 'U') &&
715                                    (rest[2] == 'e' || rest[2] == 'E'))
716                         dotw = TT_TUE;
717                   break;
718                 case 'u': case 'U':
719                   if (zone == TT_UNKNOWN &&
720                           (rest[1] == 't' || rest[1] == 'T') &&
721                           !(rest[2] >= 'A' && rest[2] <= 'Z') &&
722                           !(rest[2] >= 'a' && rest[2] <= 'z'))
723                         /* UT is the same as GMT but UTx is not. */
724                         zone = TT_GMT;
725                   break;
726                 case 'w': case 'W':
727                   if (dotw == TT_UNKNOWN &&
728                           (rest[1] == 'e' || rest[1] == 'E') &&
729                           (rest[2] == 'd' || rest[2] == 'D'))
730                         dotw = TT_WED;
731                   break;
732 
733                 case '+': case '-':
734                   {
735                         const char *end;
736                         int sign;
737                         if (zone_offset != -1)
738                           {
739                                 /* already got one... */
740                                 rest++;
741                                 break;
742                           }
743                         if (zone != TT_UNKNOWN && zone != TT_GMT)
744                           {
745                                 /* GMT+0300 is legal, but PST+0300 is not. */
746                                 rest++;
747                                 break;
748                           }
749 
750                         sign = ((*rest == '+') ? 1 : -1);
751                         rest++; /* move over sign */
752                         end = rest;
753                         while (*end >= '0' && *end <= '9')
754                           end++;
755                         if (rest == end) /* no digits here */
756                           break;
757 
758                         if ((end - rest) == 4)
759                           /* offset in HHMM */
760                           zone_offset = (((((rest[0]-'0')*10) + (rest[1]-'0')) * 60) +
761                                                          (((rest[2]-'0')*10) + (rest[3]-'0')));
762                         else if ((end - rest) == 2)
763                           /* offset in hours */
764                           zone_offset = (((rest[0]-'0')*10) + (rest[1]-'0')) * 60;
765                         else if ((end - rest) == 1)
766                           /* offset in hours */
767                           zone_offset = (rest[0]-'0') * 60;
768                         else
769                           /* 3 or >4 */
770                           break;
771 
772                         zone_offset *= sign;
773                         zone = TT_GMT;
774                         break;
775                   }
776 
777                 case '0': case '1': case '2': case '3': case '4':
778                 case '5': case '6': case '7': case '8': case '9':
779                   {
780                         int tmp_hour = -1;
781                         int tmp_min = -1;
782                         int tmp_sec = -1;
783                         int tmp_usec = -1;
784                         const char *end = rest + 1;
785                         while (*end >= '0' && *end <= '9')
786                           end++;
787 
788                         /* end is now the first character after a range of digits. */
789 
790                         if (*end == ':')
791                           {
792                                 if (hour >= 0 && min >= 0) /* already got it */
793                                   break;
794 
795                                 /* We have seen "[0-9]+:", so this is probably HH:MM[:SS] */
796                                 if ((end - rest) > 2)
797                                   /* it is [0-9][0-9][0-9]+: */
798                                   break;
799                                 else if ((end - rest) == 2)
800                                   tmp_hour = ((rest[0]-'0')*10 +
801                                                           (rest[1]-'0'));
802                                 else
803                                   tmp_hour = (rest[0]-'0');
804 
805                                 /* move over the colon, and parse minutes */
806 
807                                 rest = ++end;
808                                 while (*end >= '0' && *end <= '9')
809                                   end++;
810 
811                                 if (end == rest)
812                                   /* no digits after first colon? */
813                                   break;
814                                 else if ((end - rest) > 2)
815                                   /* it is [0-9][0-9][0-9]+: */
816                                   break;
817                                 else if ((end - rest) == 2)
818                                   tmp_min = ((rest[0]-'0')*10 +
819                                                          (rest[1]-'0'));
820                                 else
821                                   tmp_min = (rest[0]-'0');
822 
823                                 /* now go for seconds */
824                                 rest = end;
825                                 if (*rest == ':')
826                                   rest++;
827                                 end = rest;
828                                 while (*end >= '0' && *end <= '9')
829                                   end++;
830 
831                                 if (end == rest)
832                                   /* no digits after second colon - that's ok. */
833                                   ;
834                                 else if ((end - rest) > 2)
835                                   /* it is [0-9][0-9][0-9]+: */
836                                   break;
837                                 else if ((end - rest) == 2)
838                                   tmp_sec = ((rest[0]-'0')*10 +
839                                                          (rest[1]-'0'));
840                                 else
841                                   tmp_sec = (rest[0]-'0');
842 
843                                 /* fractional second */
844                                 rest = end;
845                                 if (*rest == '.')
846                                   {
847                                     rest++;
848                                     end++;
849                                     tmp_usec = 0;
850                                     /* use up to 6 digits, skip over the rest */
851                                     while (*end >= '0' && *end <= '9')
852                                       {
853                                         if (end - rest < 6)
854                                           tmp_usec = tmp_usec * 10 + *end - '0';
855                                         end++;
856                                       }
857                                     int ndigits = end - rest;
858                                     while (ndigits++ < 6)
859                                       tmp_usec *= 10;
860                                     rest = end;
861                                   }
862 
863                                 if (*rest == 'Z')
864                                   {
865                                     zone = TT_GMT;
866                                     rest++;
867                                   }
868                                 else if (tmp_hour <= 12)
869                                   {
870                                     /* If we made it here, we've parsed hour and min,
871                                        and possibly sec, so the current token is a time.
872                                        Now skip over whitespace and see if there's an AM
873                                        or PM directly following the time.
874                                     */
875                                         const char *s = end;
876                                         while (*s && (*s == ' ' || *s == '\t'))
877                                           s++;
878                                         if ((s[0] == 'p' || s[0] == 'P') &&
879                                                 (s[1] == 'm' || s[1] == 'M'))
880                                           /* 10:05pm == 22:05, and 12:05pm == 12:05 */
881                                           tmp_hour = (tmp_hour == 12 ? 12 : tmp_hour + 12);
882                                         else if (tmp_hour == 12 &&
883                                                          (s[0] == 'a' || s[0] == 'A') &&
884                                                          (s[1] == 'm' || s[1] == 'M'))
885                                           /* 12:05am == 00:05 */
886                                           tmp_hour = 0;
887                                   }
888 
889                                 hour = tmp_hour;
890                                 min = tmp_min;
891                                 sec = tmp_sec;
892                                 usec = tmp_usec;
893                                 rest = end;
894                                 break;
895                           }
896                         else if ((*end == '/' || *end == '-') &&
897                                          end[1] >= '0' && end[1] <= '9')
898                           {
899                                 /* Perhaps this is 6/16/95, 16/6/95, 6-16-95, or 16-6-95
900                                    or even 95-06-05 or 1995-06-22.
901                                  */
902                                 int n1, n2, n3;
903                                 const char *s;
904 
905                                 if (month != TT_UNKNOWN)
906                                   /* if we saw a month name, this can't be. */
907                                   break;
908 
909                                 s = rest;
910 
911                                 n1 = (*s++ - '0');                                /* first 1, 2 or 4 digits */
912                                 if (*s >= '0' && *s <= '9')
913                                   {
914                                     n1 = n1*10 + (*s++ - '0');
915 
916                                     if (*s >= '0' && *s <= '9')            /* optional digits 3 and 4 */
917                                       {
918                                         n1 = n1*10 + (*s++ - '0');
919                                         if (*s < '0' || *s > '9')
920                                           break;
921                                         n1 = n1*10 + (*s++ - '0');
922                                       }
923                                   }
924 
925                                 if (*s != '/' && *s != '-')                /* slash */
926                                   break;
927                                 s++;
928 
929                                 if (*s < '0' || *s > '9')                /* second 1 or 2 digits */
930                                   break;
931                                 n2 = (*s++ - '0');
932                                 if (*s >= '0' && *s <= '9')
933                                   n2 = n2*10 + (*s++ - '0');
934 
935                                 if (*s != '/' && *s != '-')                /* slash */
936                                   break;
937                                 s++;
938 
939                                 if (*s < '0' || *s > '9')                /* third 1, 2, 4, or 5 digits */
940                                   break;
941                                 n3 = (*s++ - '0');
942                                 if (*s >= '0' && *s <= '9')
943                                   n3 = n3*10 + (*s++ - '0');
944 
945                                 if (*s >= '0' && *s <= '9')            /* optional digits 3, 4, and 5 */
946                                   {
947                                         n3 = n3*10 + (*s++ - '0');
948                                         if (*s < '0' || *s > '9')
949                                           break;
950                                         n3 = n3*10 + (*s++ - '0');
951                                         if (*s >= '0' && *s <= '9')
952                                           n3 = n3*10 + (*s++ - '0');
953                                   }
954 
955                                 if (*s == 'T' && s[1] >= '0' && s[1] <= '9')
956                                   /* followed by ISO 8601 T delimiter and number is ok */
957                                   ;
958                                 else if ((*s >= '0' && *s <= '9') ||
959                                          (*s >= 'A' && *s <= 'Z') ||
960                                          (*s >= 'a' && *s <= 'z'))
961                                   /* but other alphanumerics are not ok */
962                                   break;
963 
964                                 /* Ok, we parsed three multi-digit numbers, with / or -
965                                    between them.  Now decide what the hell they are
966                                    (DD/MM/YY or MM/DD/YY or [YY]YY/MM/DD.)
967                                  */
968 
969                                 if (n1 > 31 || n1 == 0)  /* must be [YY]YY/MM/DD */
970                                   {
971                                         if (n2 > 12) break;
972                                         if (n3 > 31) break;
973                                         year = n1;
974                                         if (year < 70)
975                                             year += 2000;
976                                         else if (year < 100)
977                                             year += 1900;
978                                         month = (TIME_TOKEN)(n2 + ((int)TT_JAN) - 1);
979                                         date = n3;
980                                         rest = s;
981                                         break;
982                                   }
983 
984                                 if (n1 > 12 && n2 > 12)  /* illegal */
985                                   {
986                                         rest = s;
987                                         break;
988                                   }
989 
990                                 if (n3 < 70)
991                                     n3 += 2000;
992                                 else if (n3 < 100)
993                                     n3 += 1900;
994 
995                                 if (n1 > 12)  /* must be DD/MM/YY */
996                                   {
997                                         date = n1;
998                                         month = (TIME_TOKEN)(n2 + ((int)TT_JAN) - 1);
999                                         year = n3;
1000                                   }
1001                                 else                  /* assume MM/DD/YY */
1002                                   {
1003                                         /* #### In the ambiguous case, should we consult the
1004                                            locale to find out the local default? */
1005                                         month = (TIME_TOKEN)(n1 + ((int)TT_JAN) - 1);
1006                                         date = n2;
1007                                         year = n3;
1008                                   }
1009                                 rest = s;
1010                           }
1011                         else if ((*end >= 'A' && *end <= 'Z') ||
1012                                          (*end >= 'a' && *end <= 'z'))
1013                           /* Digits followed by non-punctuation - what's that? */
1014                           ;
1015                         else if ((end - rest) == 5)                /* five digits is a year */
1016                           year = (year < 0
1017                                           ? ((rest[0]-'0')*10000L +
1018                                                  (rest[1]-'0')*1000L +
1019                                                  (rest[2]-'0')*100L +
1020                                                  (rest[3]-'0')*10L +
1021                                                  (rest[4]-'0'))
1022                                           : year);
1023                         else if ((end - rest) == 4)                /* four digits is a year */
1024                           year = (year < 0
1025                                           ? ((rest[0]-'0')*1000L +
1026                                                  (rest[1]-'0')*100L +
1027                                                  (rest[2]-'0')*10L +
1028                                                  (rest[3]-'0'))
1029                                           : year);
1030                         else if ((end - rest) == 2)                /* two digits - date or year */
1031                           {
1032                                 int n = ((rest[0]-'0')*10 +
1033                                                  (rest[1]-'0'));
1034                                 /* If we don't have a date (day of the month) and we see a number
1035                                      less than 32, then assume that is the date.
1036 
1037                                          Otherwise, if we have a date and not a year, assume this is the
1038                                          year.  If it is less than 70, then assume it refers to the 21st
1039                                          century.  If it is two digits (>= 70), assume it refers to this
1040                                          century.  Otherwise, assume it refers to an unambiguous year.
1041 
1042                                          The world will surely end soon.
1043                                    */
1044                                 if (date < 0 && n < 32)
1045                                   date = n;
1046                                 else if (year < 0)
1047                                   {
1048                                         if (n < 70)
1049                                           year = 2000 + n;
1050                                         else if (n < 100)
1051                                           year = 1900 + n;
1052                                         else
1053                                           year = n;
1054                                   }
1055                                 /* else what the hell is this. */
1056                           }
1057                         else if ((end - rest) == 1)                /* one digit - date */
1058                           date = (date < 0 ? (rest[0]-'0') : date);
1059                         /* else, three or more than five digits - what's that? */
1060 
1061                         break;
1062                   }   /* case '0' .. '9' */
1063                 }   /* switch */
1064 
1065           /* Skip to the end of this token, whether we parsed it or not.
1066              Tokens are delimited by whitespace, or ,;-+/()[] but explicitly not .:
1067              'T' is also treated as delimiter when followed by a digit (ISO 8601).
1068            */
1069           while (*rest &&
1070                          *rest != ' ' && *rest != '\t' &&
1071                          *rest != ',' && *rest != ';' &&
1072                          *rest != '-' && *rest != '+' &&
1073                          *rest != '/' &&
1074                          *rest != '(' && *rest != ')' && *rest != '[' && *rest != ']' &&
1075                          !(*rest == 'T' && rest[1] >= '0' && rest[1] <= '9')
1076                 )
1077                 rest++;
1078           /* skip over uninteresting chars. */
1079         SKIP_MORE:
1080           while (*rest == ' ' || *rest == '\t' ||
1081                  *rest == ',' || *rest == ';' || *rest == '/' ||
1082                  *rest == '(' || *rest == ')' || *rest == '[' || *rest == ']')
1083                 rest++;
1084 
1085           /* "-" is ignored at the beginning of a token if we have not yet
1086                  parsed a year (e.g., the second "-" in "30-AUG-1966"), or if
1087                  the character after the dash is not a digit. */
1088           if (*rest == '-' && ((rest > string &&
1089               isalpha((unsigned char)rest[-1]) && year < 0) ||
1090               rest[1] < '0' || rest[1] > '9'))
1091                 {
1092                   rest++;
1093                   goto SKIP_MORE;
1094                 }
1095 
1096           /* Skip T that may precede ISO 8601 time. */
1097           if (*rest == 'T' && rest[1] >= '0' && rest[1] <= '9')
1098             rest++;
1099         }   /* while */
1100 
1101   if (zone != TT_UNKNOWN && zone_offset == -1)
1102         {
1103           switch (zone)
1104                 {
1105                 case TT_PST: zone_offset = -8 * 60; break;
1106                 case TT_PDT: zone_offset = -8 * 60; dst_offset = 1 * 60; break;
1107                 case TT_MST: zone_offset = -7 * 60; break;
1108                 case TT_MDT: zone_offset = -7 * 60; dst_offset = 1 * 60; break;
1109                 case TT_CST: zone_offset = -6 * 60; break;
1110                 case TT_CDT: zone_offset = -6 * 60; dst_offset = 1 * 60; break;
1111                 case TT_EST: zone_offset = -5 * 60; break;
1112                 case TT_EDT: zone_offset = -5 * 60; dst_offset = 1 * 60; break;
1113                 case TT_AST: zone_offset = -4 * 60; break;
1114                 case TT_NST: zone_offset = -3 * 60 - 30; break;
1115                 case TT_GMT: zone_offset =  0 * 60; break;
1116                 case TT_BST: zone_offset =  0 * 60; dst_offset = 1 * 60; break;
1117                 case TT_MET: zone_offset =  1 * 60; break;
1118                 case TT_EET: zone_offset =  2 * 60; break;
1119                 case TT_JST: zone_offset =  9 * 60; break;
1120                 default:
1121                   PR_ASSERT (0);
1122                   break;
1123                 }
1124         }
1125 
1126   /* If we didn't find a year, month, or day-of-the-month, we can't
1127          possibly parse this, and in fact, mktime() will do something random
1128          (I'm seeing it return "Tue Feb  5 06:28:16 2036", which is no doubt
1129          a numerologically significant date... */
1130   if (month == TT_UNKNOWN || date == -1 || year == -1 || year > PR_INT16_MAX)
1131       return PR_FAILURE;
1132 
1133   memset(result, 0, sizeof(*result));
1134   if (usec != -1)
1135         result->tm_usec = usec;
1136   if (sec != -1)
1137         result->tm_sec = sec;
1138   if (min != -1)
1139         result->tm_min = min;
1140   if (hour != -1)
1141         result->tm_hour = hour;
1142   if (date != -1)
1143         result->tm_mday = date;
1144   if (month != TT_UNKNOWN)
1145         result->tm_month = (((int)month) - ((int)TT_JAN));
1146   if (year != -1)
1147         result->tm_year = year;
1148   if (dotw != TT_UNKNOWN)
1149         result->tm_wday = (((int)dotw) - ((int)TT_SUN));
1150   /*
1151    * Mainly to compute wday and yday, but normalized time is also required
1152    * by the check below that works around a Visual C++ 2005 mktime problem.
1153    */
1154   PR_NormalizeTime(result, PR_GMTParameters);
1155   /* The remaining work is to set the gmt and dst offsets in tm_params. */
1156 
1157   if (zone == TT_UNKNOWN && default_to_gmt)
1158         {
1159           /* No zone was specified, so pretend the zone was GMT. */
1160           zone = TT_GMT;
1161           zone_offset = 0;
1162         }
1163 
1164   if (zone_offset == -1)
1165          {
1166            /* no zone was specified, and we're to assume that everything
1167              is local. */
1168           struct tm localTime;
1169           time_t secs;
1170 
1171           PR_ASSERT(result->tm_month > -1 &&
1172                     result->tm_mday > 0 &&
1173                     result->tm_hour > -1 &&
1174                     result->tm_min > -1 &&
1175                     result->tm_sec > -1);
1176 
1177             /*
1178              * To obtain time_t from a tm structure representing the local
1179              * time, we call mktime().  However, we need to see if we are
1180              * on 1-Jan-1970 or before.  If we are, we can't call mktime()
1181              * because mktime() will crash on win16. In that case, we
1182              * calculate zone_offset based on the zone offset at
1183              * 00:00:00, 2 Jan 1970 GMT, and subtract zone_offset from the
1184              * date we are parsing to transform the date to GMT.  We also
1185              * do so if mktime() returns (time_t) -1 (time out of range).
1186            */
1187 
1188           /* month, day, hours, mins and secs are always non-negative
1189              so we dont need to worry about them. */
1190           if (result->tm_year >= 1970)
1191                 {
1192                   localTime.tm_sec = result->tm_sec;
1193                   localTime.tm_min = result->tm_min;
1194                   localTime.tm_hour = result->tm_hour;
1195                   localTime.tm_mday = result->tm_mday;
1196                   localTime.tm_mon = result->tm_month;
1197                   localTime.tm_year = result->tm_year - 1900;
1198                   /* Set this to -1 to tell mktime "I don't care".  If you set
1199                      it to 0 or 1, you are making assertions about whether the
1200                      date you are handing it is in daylight savings mode or not;
1201                      and if you're wrong, it will "fix" it for you. */
1202                   localTime.tm_isdst = -1;
1203 
1204 #if _MSC_VER == 1400  /* 1400 = Visual C++ 2005 (8.0) */
1205                   /*
1206                    * mktime will return (time_t) -1 if the input is a date
1207                    * after 23:59:59, December 31, 3000, US Pacific Time (not
1208                    * UTC as documented):
1209                    * http://msdn.microsoft.com/en-us/library/d1y53h2a(VS.80).aspx
1210                    * But if the year is 3001, mktime also invokes the invalid
1211                    * parameter handler, causing the application to crash.  This
1212                    * problem has been reported in
1213                    * http://connect.microsoft.com/VisualStudio/feedback/ViewFeedback.aspx?FeedbackID=266036.
1214                    * We avoid this crash by not calling mktime if the date is
1215                    * out of range.  To use a simple test that works in any time
1216                    * zone, we consider year 3000 out of range as well.  (See
1217                    * bug 480740.)
1218                    */
1219                   if (result->tm_year >= 3000) {
1220                       /* Emulate what mktime would have done. */
1221                       errno = EINVAL;
1222                       secs = (time_t) -1;
1223                   } else {
1224                       secs = mktime(&localTime);
1225                   }
1226 #else
1227                   secs = mktime(&localTime);
1228 #endif
1229                   if (secs != (time_t) -1)
1230                     {
1231                       *result_imploded = (PRInt64)secs * PR_USEC_PER_SEC;
1232                       *result_imploded += result->tm_usec;
1233                       return PR_SUCCESS;
1234                     }
1235                 }
1236 
1237                 /* So mktime() can't handle this case.  We assume the
1238                    zone_offset for the date we are parsing is the same as
1239                    the zone offset on 00:00:00 2 Jan 1970 GMT. */
1240                 secs = 86400;
1241                 localtime_r(&secs, &localTime);
1242                 zone_offset = localTime.tm_min
1243                               + 60 * localTime.tm_hour
1244                               + 1440 * (localTime.tm_mday - 2);
1245         }
1246 
1247   result->tm_params.tp_gmt_offset = zone_offset * 60;
1248   result->tm_params.tp_dst_offset = dst_offset * 60;
1249 
1250   *result_imploded = PR_ImplodeTime(result);
1251   return PR_SUCCESS;
1252 }
1253