1 /*
2 * Copyright (C) 1999-2000 Harri Porten (porten@kde.org)
3 * Copyright (C) 2006, 2007 Apple Inc. All rights reserved.
4 * Copyright (C) 2009 Google Inc. All rights reserved.
5 * Copyright (C) 2007-2009 Torch Mobile, Inc.
6 * Copyright (C) 2010 &yet, LLC. (nate@andyet.net)
7 *
8 * The Original Code is Mozilla Communicator client code, released
9 * March 31, 1998.
10 *
11 * The Initial Developer of the Original Code is
12 * Netscape Communications Corporation.
13 * Portions created by the Initial Developer are Copyright (C) 1998
14 * the Initial Developer. All Rights Reserved.
15 *
16 * This library is free software; you can redistribute it and/or
17 * modify it under the terms of the GNU Lesser General Public
18 * License as published by the Free Software Foundation; either
19 * version 2.1 of the License, or (at your option) any later version.
20 *
21 * This library is distributed in the hope that it will be useful,
22 * but WITHOUT ANY WARRANTY; without even the implied warranty of
23 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
24 * Lesser General Public License for more details.
25 *
26 * You should have received a copy of the GNU Lesser General Public
27 * License along with this library; if not, write to the Free Software
28 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
29 *
30 * Alternatively, the contents of this file may be used under the terms
31 * of either the Mozilla Public License Version 1.1, found at
32 * http://www.mozilla.org/MPL/ (the "MPL") or the GNU General Public
33 * License Version 2.0, found at http://www.fsf.org/copyleft/gpl.html
34 * (the "GPL"), in which case the provisions of the MPL or the GPL are
35 * applicable instead of those above. If you wish to allow use of your
36 * version of this file only under the terms of one of those two
37 * licenses (the MPL or the GPL) and not to allow others to use your
38 * version of this file under the LGPL, indicate your decision by
39 * deletingthe provisions above and replace them with the notice and
40 * other provisions required by the MPL or the GPL, as the case may be.
41 * If you do not delete the provisions above, a recipient may use your
42 * version of this file under any of the LGPL, the MPL or the GPL.
43
44 * Copyright 2006-2008 the V8 project authors. All rights reserved.
45 * Redistribution and use in source and binary forms, with or without
46 * modification, are permitted provided that the following conditions are
47 * met:
48 *
49 * * Redistributions of source code must retain the above copyright
50 * notice, this list of conditions and the following disclaimer.
51 * * Redistributions in binary form must reproduce the above
52 * copyright notice, this list of conditions and the following
53 * disclaimer in the documentation and/or other materials provided
54 * with the distribution.
55 * * Neither the name of Google Inc. nor the names of its
56 * contributors may be used to endorse or promote products derived
57 * from this software without specific prior written permission.
58 *
59 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
60 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
61 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
62 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
63 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
64 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
65 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
66 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
67 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
68 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
69 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
70 */
71
72 #include "config.h"
73 #include "DateMath.h"
74
75 #include "Assertions.h"
76 #include "ASCIICType.h"
77 #include "CurrentTime.h"
78 #include "MathExtras.h"
79 #include "StdLibExtras.h"
80 #include "StringExtras.h"
81
82 #include <algorithm>
83 #include <limits.h>
84 #include <limits>
85 #include <stdint.h>
86 #include <time.h>
87 #include <wtf/text/StringBuilder.h>
88
89 #if OS(WINDOWS)
90 #include <windows.h>
91 #endif
92
93 #if HAVE(ERRNO_H)
94 #include <errno.h>
95 #endif
96
97 #if HAVE(SYS_TIME_H)
98 #include <sys/time.h>
99 #endif
100
101 #if HAVE(SYS_TIMEB_H)
102 #include <sys/timeb.h>
103 #endif
104
105 using namespace WTF;
106
107 namespace WTF {
108
109 /* Constants */
110
111 static const double maxUnixTime = 2145859200.0; // 12/31/2037
112 // ECMAScript asks not to support for a date of which total
113 // millisecond value is larger than the following value.
114 // See 15.9.1.14 of ECMA-262 5th edition.
115 static const double maxECMAScriptTime = 8.64E15;
116
117 // Day of year for the first day of each month, where index 0 is January, and day 0 is January 1.
118 // First for non-leap years, then for leap years.
119 static const int firstDayOfMonth[2][12] = {
120 {0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334},
121 {0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335}
122 };
123
124 #if !OS(WINCE)
125 static inline void getLocalTime(const time_t* localTime, struct tm* localTM)
126 {
127 #if COMPILER(MINGW)
128 *localTM = *localtime(localTime);
129 #elif COMPILER(MSVC)
130 localtime_s(localTM, localTime);
131 #else
132 localtime_r(localTime, localTM);
133 #endif
134 }
135 #endif
136
137 bool isLeapYear(int year)
138 {
139 if (year % 4 != 0)
140 return false;
141 if (year % 400 == 0)
142 return true;
143 if (year % 100 == 0)
144 return false;
145 return true;
146 }
147
148 static inline int daysInYear(int year)
149 {
150 return 365 + isLeapYear(year);
151 }
152
153 static inline double daysFrom1970ToYear(int year)
154 {
155 // The Gregorian Calendar rules for leap years:
156 // Every fourth year is a leap year. 2004, 2008, and 2012 are leap years.
157 // However, every hundredth year is not a leap year. 1900 and 2100 are not leap years.
158 // Every four hundred years, there's a leap year after all. 2000 and 2400 are leap years.
159
160 static const int leapDaysBefore1971By4Rule = 1970 / 4;
161 static const int excludedLeapDaysBefore1971By100Rule = 1970 / 100;
162 static const int leapDaysBefore1971By400Rule = 1970 / 400;
163
164 const double yearMinusOne = year - 1;
165 const double yearsToAddBy4Rule = floor(yearMinusOne / 4.0) - leapDaysBefore1971By4Rule;
166 const double yearsToExcludeBy100Rule = floor(yearMinusOne / 100.0) - excludedLeapDaysBefore1971By100Rule;
167 const double yearsToAddBy400Rule = floor(yearMinusOne / 400.0) - leapDaysBefore1971By400Rule;
168
169 return 365.0 * (year - 1970) + yearsToAddBy4Rule - yearsToExcludeBy100Rule + yearsToAddBy400Rule;
170 }
171
172 double msToDays(double ms)
173 {
174 return floor(ms / msPerDay);
175 }
176
177 static void appendTwoDigitNumber(StringBuilder& builder, int number)
178 {
179 ASSERT(number >= 0);
180 ASSERT(number < 100);
181 builder.append(static_cast<LChar>('0' + number / 10));
182 builder.append(static_cast<LChar>('0' + number % 10));
183 }
184
185 int msToYear(double ms)
186 {
187 int approxYear = static_cast<int>(floor(ms / (msPerDay * 365.2425)) + 1970);
188 double msFromApproxYearTo1970 = msPerDay * daysFrom1970ToYear(approxYear);
189 if (msFromApproxYearTo1970 > ms)
190 return approxYear - 1;
191 if (msFromApproxYearTo1970 + msPerDay * daysInYear(approxYear) <= ms)
192 return approxYear + 1;
193 return approxYear;
194 }
195
196 int dayInYear(double ms, int year)
197 {
198 return static_cast<int>(msToDays(ms) - daysFrom1970ToYear(year));
199 }
200
201 static inline double msToMilliseconds(double ms)
202 {
203 double result = fmod(ms, msPerDay);
204 if (result < 0)
205 result += msPerDay;
206 return result;
207 }
208
209 int msToMinutes(double ms)
210 {
211 double result = fmod(floor(ms / msPerMinute), minutesPerHour);
212 if (result < 0)
213 result += minutesPerHour;
214 return static_cast<int>(result);
215 }
216
217 int msToHours(double ms)
218 {
219 double result = fmod(floor(ms/msPerHour), hoursPerDay);
220 if (result < 0)
221 result += hoursPerDay;
222 return static_cast<int>(result);
223 }
224
225 int monthFromDayInYear(int dayInYear, bool leapYear)
226 {
227 const int d = dayInYear;
228 int step;
229
230 if (d < (step = 31))
231 return 0;
232 step += (leapYear ? 29 : 28);
233 if (d < step)
234 return 1;
235 if (d < (step += 31))
236 return 2;
237 if (d < (step += 30))
238 return 3;
239 if (d < (step += 31))
240 return 4;
241 if (d < (step += 30))
242 return 5;
243 if (d < (step += 31))
244 return 6;
245 if (d < (step += 31))
246 return 7;
247 if (d < (step += 30))
248 return 8;
249 if (d < (step += 31))
250 return 9;
251 if (d < (step += 30))
252 return 10;
253 return 11;
254 }
255
256 static inline bool checkMonth(int dayInYear, int& startDayOfThisMonth, int& startDayOfNextMonth, int daysInThisMonth)
257 {
258 startDayOfThisMonth = startDayOfNextMonth;
259 startDayOfNextMonth += daysInThisMonth;
260 return (dayInYear <= startDayOfNextMonth);
261 }
262
263 int dayInMonthFromDayInYear(int dayInYear, bool leapYear)
264 {
265 const int d = dayInYear;
266 int step;
267 int next = 30;
268
269 if (d <= next)
270 return d + 1;
271 const int daysInFeb = (leapYear ? 29 : 28);
272 if (checkMonth(d, step, next, daysInFeb))
273 return d - step;
274 if (checkMonth(d, step, next, 31))
275 return d - step;
276 if (checkMonth(d, step, next, 30))
277 return d - step;
278 if (checkMonth(d, step, next, 31))
279 return d - step;
280 if (checkMonth(d, step, next, 30))
281 return d - step;
282 if (checkMonth(d, step, next, 31))
283 return d - step;
284 if (checkMonth(d, step, next, 31))
285 return d - step;
286 if (checkMonth(d, step, next, 30))
287 return d - step;
288 if (checkMonth(d, step, next, 31))
289 return d - step;
290 if (checkMonth(d, step, next, 30))
291 return d - step;
292 step = next;
293 return d - step;
294 }
295
296 int dayInYear(int year, int month, int day)
297 {
298 return firstDayOfMonth[isLeapYear(year)][month] + day - 1;
299 }
300
301 double dateToDaysFrom1970(int year, int month, int day)
302 {
303 year += month / 12;
304
305 month %= 12;
306 if (month < 0) {
307 month += 12;
308 --year;
309 }
310
311 double yearday = floor(daysFrom1970ToYear(year));
312 ASSERT((year >= 1970 && yearday >= 0) || (year < 1970 && yearday < 0));
313 return yearday + dayInYear(year, month, day);
314 }
315
316 // There is a hard limit at 2038 that we currently do not have a workaround
317 // for (rdar://problem/5052975).
318 static inline int maximumYearForDST()
319 {
320 return 2037;
321 }
322
323 static inline int minimumYearForDST()
324 {
325 // Because of the 2038 issue (see maximumYearForDST) if the current year is
326 // greater than the max year minus 27 (2010), we want to use the max year
327 // minus 27 instead, to ensure there is a range of 28 years that all years
328 // can map to.
329 return std::min(msToYear(jsCurrentTime()), maximumYearForDST() - 27) ;
330 }
331
332 /*
333 * Find an equivalent year for the one given, where equivalence is deterined by
334 * the two years having the same leapness and the first day of the year, falling
335 * on the same day of the week.
336 *
337 * This function returns a year between this current year and 2037, however this
338 * function will potentially return incorrect results if the current year is after
339 * 2010, (rdar://problem/5052975), if the year passed in is before 1900 or after
340 * 2100, (rdar://problem/5055038).
341 */
342 int equivalentYearForDST(int year)
343 {
344 // It is ok if the cached year is not the current year as long as the rules
345 // for DST did not change between the two years; if they did the app would need
346 // to be restarted.
347 static int minYear = minimumYearForDST();
348 int maxYear = maximumYearForDST();
349
350 int difference;
351 if (year > maxYear)
352 difference = minYear - year;
353 else if (year < minYear)
354 difference = maxYear - year;
355 else
356 return year;
357
358 int quotient = difference / 28;
359 int product = (quotient) * 28;
360
361 year += product;
362 ASSERT((year >= minYear && year <= maxYear) || (product - year == static_cast<int>(std::numeric_limits<double>::quiet_NaN())));
363 return year;
364 }
365
366 #if !HAVE(TM_GMTOFF)
367
368 static int32_t calculateUTCOffset()
369 {
370 #if OS(WINDOWS)
371 TIME_ZONE_INFORMATION timeZoneInformation;
372 GetTimeZoneInformation(&timeZoneInformation);
373 int32_t bias = timeZoneInformation.Bias + timeZoneInformation.StandardBias;
374 return -bias * 60 * 1000;
375 #else
376 time_t localTime = time(0);
377 tm localt;
378 getLocalTime(&localTime, &localt);
379
380 // Get the difference between this time zone and UTC on the 1st of January of this year.
381 localt.tm_sec = 0;
382 localt.tm_min = 0;
383 localt.tm_hour = 0;
384 localt.tm_mday = 1;
385 localt.tm_mon = 0;
386 // Not setting localt.tm_year!
387 localt.tm_wday = 0;
388 localt.tm_yday = 0;
389 localt.tm_isdst = 0;
390 #if HAVE(TM_GMTOFF)
391 localt.tm_gmtoff = 0;
392 #endif
393 #if HAVE(TM_ZONE)
394 localt.tm_zone = 0;
395 #endif
396
397 #if HAVE(TIMEGM)
398 time_t utcOffset = timegm(&localt) - mktime(&localt);
399 #else
400 // Using a canned date of 01/01/2009 on platforms with weaker date-handling foo.
401 localt.tm_year = 109;
402 time_t utcOffset = 1230768000 - mktime(&localt);
403 #endif
404
405 return static_cast<int32_t>(utcOffset * 1000);
406 #endif
407 }
408
409 #if OS(WINDOWS)
410 // Code taken from http://support.microsoft.com/kb/167296
411 static void UnixTimeToFileTime(time_t t, LPFILETIME pft)
412 {
413 // Note that LONGLONG is a 64-bit value
414 LONGLONG ll;
415
416 ll = Int32x32To64(t, 10000000) + 116444736000000000;
417 pft->dwLowDateTime = (DWORD)ll;
418 pft->dwHighDateTime = ll >> 32;
419 }
420 #endif
421
422 /*
423 * Get the DST offset for the time passed in.
424 */
425 static double calculateDSTOffset(time_t localTime, double utcOffset)
426 {
427 #if OS(WINCE)
428 UNUSED_PARAM(localTime);
429 UNUSED_PARAM(utcOffset);
430 return 0;
431 #elif OS(WINDOWS)
432 FILETIME utcFileTime;
433 UnixTimeToFileTime(localTime, &utcFileTime);
434 SYSTEMTIME utcSystemTime, localSystemTime;
435 FileTimeToSystemTime(&utcFileTime, &utcSystemTime);
436 SystemTimeToTzSpecificLocalTime(0, &utcSystemTime, &localSystemTime);
437
438 double offsetTime = (localTime * msPerSecond) + utcOffset;
439
440 // Offset from UTC but doesn't include DST obviously
441 int offsetHour = msToHours(offsetTime);
442 int offsetMinute = msToMinutes(offsetTime);
443
444 double diff = ((localSystemTime.wHour - offsetHour) * secondsPerHour) + ((localSystemTime.wMinute - offsetMinute) * 60);
445
446 // See: https://bugs.webkit.org/show_bug.cgi?id=137003
447 #if PLATFORM(JAVA)
448 if (diff < 0)
449 diff += secondsPerDay;
450 #endif
451
452 return diff * msPerSecond;
453 #else
454 //input is UTC so we have to shift back to local time to determine DST thus the + getUTCOffset()
455 double offsetTime = (localTime * msPerSecond) + utcOffset;
456
457 // Offset from UTC but doesn't include DST obviously
458 int offsetHour = msToHours(offsetTime);
459 int offsetMinute = msToMinutes(offsetTime);
460
461 tm localTM;
462 getLocalTime(&localTime, &localTM);
463
464 double diff = ((localTM.tm_hour - offsetHour) * secondsPerHour) + ((localTM.tm_min - offsetMinute) * 60);
465
466 if (diff < 0)
467 diff += secondsPerDay;
468
469 return (diff * msPerSecond);
470 #endif
471 }
472
473 #endif
474
475 // Returns combined offset in millisecond (UTC + DST).
476 LocalTimeOffset calculateLocalTimeOffset(double ms)
477 {
478 // On Mac OS X, the call to localtime (see calculateDSTOffset) will return historically accurate
479 // DST information (e.g. New Zealand did not have DST from 1946 to 1974) however the JavaScript
480 // standard explicitly dictates that historical information should not be considered when
481 // determining DST. For this reason we shift away from years that localtime can handle but would
482 // return historically accurate information.
483 int year = msToYear(ms);
484 int equivalentYear = equivalentYearForDST(year);
485 if (year != equivalentYear) {
486 bool leapYear = isLeapYear(year);
487 int dayInYearLocal = dayInYear(ms, year);
488 int dayInMonth = dayInMonthFromDayInYear(dayInYearLocal, leapYear);
489 int month = monthFromDayInYear(dayInYearLocal, leapYear);
490 double day = dateToDaysFrom1970(equivalentYear, month, dayInMonth);
491 ms = (day * msPerDay) + msToMilliseconds(ms);
492 }
493
494 double localTimeSeconds = ms / msPerSecond;
495 if (localTimeSeconds > maxUnixTime)
496 localTimeSeconds = maxUnixTime;
497 else if (localTimeSeconds < 0) // Go ahead a day to make localtime work (does not work with 0).
498 localTimeSeconds += secondsPerDay;
499 // FIXME: time_t has a potential problem in 2038.
500 time_t localTime = static_cast<time_t>(localTimeSeconds);
501
502 #if HAVE(TM_GMTOFF)
503 tm localTM;
504 getLocalTime(&localTime, &localTM);
505 return LocalTimeOffset(localTM.tm_isdst, localTM.tm_gmtoff * msPerSecond);
506 #else
507 double utcOffset = calculateUTCOffset();
508 double dstOffset = calculateDSTOffset(localTime, utcOffset);
509 return LocalTimeOffset(dstOffset, utcOffset + dstOffset);
510 #endif
511 }
512
513 void initializeDates()
514 {
515 #if !ASSERT_DISABLED
516 static bool alreadyInitialized;
517 ASSERT(!alreadyInitialized);
518 alreadyInitialized = true;
519 #endif
520
521 equivalentYearForDST(2000); // Need to call once to initialize a static used in this function.
522 }
523
524 static inline double ymdhmsToSeconds(int year, long mon, long day, long hour, long minute, double second)
525 {
526 double days = (day - 32075)
527 + floor(1461 * (year + 4800.0 + (mon - 14) / 12) / 4)
528 + 367 * (mon - 2 - (mon - 14) / 12 * 12) / 12
529 - floor(3 * ((year + 4900.0 + (mon - 14) / 12) / 100) / 4)
530 - 2440588;
531 return ((days * hoursPerDay + hour) * minutesPerHour + minute) * secondsPerMinute + second;
532 }
533
534 // We follow the recommendation of RFC 2822 to consider all
535 // obsolete time zones not listed here equivalent to "-0000".
536 static const struct KnownZone {
537 #if !OS(WINDOWS)
538 const
539 #endif
540 char tzName[4];
541 int tzOffset;
542 } known_zones[] = {
543 { "UT", 0 },
544 { "GMT", 0 },
545 { "EST", -300 },
546 { "EDT", -240 },
547 { "CST", -360 },
548 { "CDT", -300 },
549 { "MST", -420 },
550 { "MDT", -360 },
551 { "PST", -480 },
552 { "PDT", -420 }
553 };
554
555 inline static void skipSpacesAndComments(const char*& s)
556 {
557 int nesting = 0;
558 char ch;
559 while ((ch = *s)) {
560 if (!isASCIISpace(ch)) {
561 if (ch == '(')
562 nesting++;
563 else if (ch == ')' && nesting > 0)
564 nesting--;
565 else if (nesting == 0)
566 break;
567 }
568 s++;
569 }
570 }
571
572 // returns 0-11 (Jan-Dec); -1 on failure
573 static int findMonth(const char* monthStr)
574 {
575 ASSERT(monthStr);
576 char needle[4];
577 for (int i = 0; i < 3; ++i) {
578 if (!*monthStr)
579 return -1;
580 needle[i] = static_cast<char>(toASCIILower(*monthStr++));
581 }
582 needle[3] = '\0';
583 const char *haystack = "janfebmaraprmayjunjulaugsepoctnovdec";
584 const char *str = strstr(haystack, needle);
585 if (str) {
586 int position = static_cast<int>(str - haystack);
587 if (position % 3 == 0)
588 return position / 3;
589 }
590 return -1;
591 }
592
593 static bool parseInt(const char* string, char** stopPosition, int base, int* result)
594 {
595 long longResult = strtol(string, stopPosition, base);
596 // Avoid the use of errno as it is not available on Windows CE
597 if (string == *stopPosition || longResult <= std::numeric_limits<int>::min() || longResult >= std::numeric_limits<int>::max())
598 return false;
599 *result = static_cast<int>(longResult);
600 return true;
601 }
602
603 static bool parseLong(const char* string, char** stopPosition, int base, long* result)
604 {
605 *result = strtol(string, stopPosition, base);
606 // Avoid the use of errno as it is not available on Windows CE
607 if (string == *stopPosition || *result == std::numeric_limits<long>::min() || *result == std::numeric_limits<long>::max())
608 return false;
609 return true;
610 }
611
612 // Parses a date with the format YYYY[-MM[-DD]].
613 // Year parsing is lenient, allows any number of digits, and +/-.
614 // Returns 0 if a parse error occurs, else returns the end of the parsed portion of the string.
615 static char* parseES5DatePortion(const char* currentPosition, int& year, long& month, long& day)
616 {
617 char* postParsePosition;
618
619 // This is a bit more lenient on the year string than ES5 specifies:
620 // instead of restricting to 4 digits (or 6 digits with mandatory +/-),
621 // it accepts any integer value. Consider this an implementation fallback.
622 if (!parseInt(currentPosition, &postParsePosition, 10, &year))
623 return 0;
624
625 // Check for presence of -MM portion.
626 if (*postParsePosition != '-')
627 return postParsePosition;
628 currentPosition = postParsePosition + 1;
629
630 if (!isASCIIDigit(*currentPosition))
631 return 0;
632 if (!parseLong(currentPosition, &postParsePosition, 10, &month))
633 return 0;
634 if ((postParsePosition - currentPosition) != 2)
635 return 0;
636
637 // Check for presence of -DD portion.
638 if (*postParsePosition != '-')
639 return postParsePosition;
640 currentPosition = postParsePosition + 1;
641
642 if (!isASCIIDigit(*currentPosition))
643 return 0;
644 if (!parseLong(currentPosition, &postParsePosition, 10, &day))
645 return 0;
646 if ((postParsePosition - currentPosition) != 2)
647 return 0;
648 return postParsePosition;
649 }
650
651 // Parses a time with the format HH:mm[:ss[.sss]][Z|(+|-)00:00].
652 // Fractional seconds parsing is lenient, allows any number of digits.
653 // Returns 0 if a parse error occurs, else returns the end of the parsed portion of the string.
654 static char* parseES5TimePortion(char* currentPosition, long& hours, long& minutes, double& seconds, long& timeZoneSeconds)
655 {
656 char* postParsePosition;
657 if (!isASCIIDigit(*currentPosition))
658 return 0;
659 if (!parseLong(currentPosition, &postParsePosition, 10, &hours))
660 return 0;
661 if (*postParsePosition != ':' || (postParsePosition - currentPosition) != 2)
662 return 0;
663 currentPosition = postParsePosition + 1;
664
665 if (!isASCIIDigit(*currentPosition))
666 return 0;
667 if (!parseLong(currentPosition, &postParsePosition, 10, &minutes))
668 return 0;
669 if ((postParsePosition - currentPosition) != 2)
670 return 0;
671 currentPosition = postParsePosition;
672
673 // Seconds are optional.
674 if (*currentPosition == ':') {
675 ++currentPosition;
676
677 long intSeconds;
678 if (!isASCIIDigit(*currentPosition))
679 return 0;
680 if (!parseLong(currentPosition, &postParsePosition, 10, &intSeconds))
681 return 0;
682 if ((postParsePosition - currentPosition) != 2)
683 return 0;
684 seconds = intSeconds;
685 if (*postParsePosition == '.') {
686 currentPosition = postParsePosition + 1;
687
688 // In ECMA-262-5 it's a bit unclear if '.' can be present without milliseconds, but
689 // a reasonable interpretation guided by the given examples and RFC 3339 says "no".
690 // We check the next character to avoid reading +/- timezone hours after an invalid decimal.
691 if (!isASCIIDigit(*currentPosition))
692 return 0;
693
694 // We are more lenient than ES5 by accepting more or less than 3 fraction digits.
695 long fracSeconds;
696 if (!parseLong(currentPosition, &postParsePosition, 10, &fracSeconds))
697 return 0;
698
699 long numFracDigits = postParsePosition - currentPosition;
700 seconds += fracSeconds * pow(10.0, static_cast<double>(-numFracDigits));
701 }
702 currentPosition = postParsePosition;
703 }
704
705 if (*currentPosition == 'Z')
706 return currentPosition + 1;
707
708 bool tzNegative;
709 if (*currentPosition == '-')
710 tzNegative = true;
711 else if (*currentPosition == '+')
712 tzNegative = false;
713 else
714 return currentPosition; // no timezone
715 ++currentPosition;
716
717 long tzHours;
718 long tzHoursAbs;
719 long tzMinutes;
720
721 if (!isASCIIDigit(*currentPosition))
722 return 0;
723 if (!parseLong(currentPosition, &postParsePosition, 10, &tzHours))
724 return 0;
725 if (*postParsePosition != ':' || (postParsePosition - currentPosition) != 2)
726 return 0;
727 tzHoursAbs = labs(tzHours);
728 currentPosition = postParsePosition + 1;
729
730 if (!isASCIIDigit(*currentPosition))
731 return 0;
732 if (!parseLong(currentPosition, &postParsePosition, 10, &tzMinutes))
733 return 0;
734 if ((postParsePosition - currentPosition) != 2)
735 return 0;
736 currentPosition = postParsePosition;
737
738 if (tzHoursAbs > 24)
739 return 0;
740 if (tzMinutes < 0 || tzMinutes > 59)
741 return 0;
742
743 timeZoneSeconds = 60 * (tzMinutes + (60 * tzHoursAbs));
744 if (tzNegative)
745 timeZoneSeconds = -timeZoneSeconds;
746
747 return currentPosition;
748 }
749
750 double parseES5DateFromNullTerminatedCharacters(const char* dateString)
751 {
752 // This parses a date of the form defined in ECMA-262-5, section 15.9.1.15
753 // (similar to RFC 3339 / ISO 8601: YYYY-MM-DDTHH:mm:ss[.sss]Z).
754 // In most cases it is intentionally strict (e.g. correct field widths, no stray whitespace).
755
756 static const long daysPerMonth[12] = { 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
757
758 // The year must be present, but the other fields may be omitted - see ES5.1 15.9.1.15.
759 int year = 0;
760 long month = 1;
761 long day = 1;
762 long hours = 0;
763 long minutes = 0;
764 double seconds = 0;
765 long timeZoneSeconds = 0;
766
767 // Parse the date YYYY[-MM[-DD]]
768 char* currentPosition = parseES5DatePortion(dateString, year, month, day);
769 if (!currentPosition)
770 return std::numeric_limits<double>::quiet_NaN();
771 // Look for a time portion.
772 if (*currentPosition == 'T') {
773 // Parse the time HH:mm[:ss[.sss]][Z|(+|-)00:00]
774 currentPosition = parseES5TimePortion(currentPosition + 1, hours, minutes, seconds, timeZoneSeconds);
775 if (!currentPosition)
776 return std::numeric_limits<double>::quiet_NaN();
777 }
778 // Check that we have parsed all characters in the string.
779 if (*currentPosition)
780 return std::numeric_limits<double>::quiet_NaN();
781
782 // A few of these checks could be done inline above, but since many of them are interrelated
783 // we would be sacrificing readability to "optimize" the (presumably less common) failure path.
784 if (month < 1 || month > 12)
785 return std::numeric_limits<double>::quiet_NaN();
786 if (day < 1 || day > daysPerMonth[month - 1])
787 return std::numeric_limits<double>::quiet_NaN();
788 if (month == 2 && day > 28 && !isLeapYear(year))
789 return std::numeric_limits<double>::quiet_NaN();
790 if (hours < 0 || hours > 24)
791 return std::numeric_limits<double>::quiet_NaN();
792 if (hours == 24 && (minutes || seconds))
793 return std::numeric_limits<double>::quiet_NaN();
794 if (minutes < 0 || minutes > 59)
795 return std::numeric_limits<double>::quiet_NaN();
796 if (seconds < 0 || seconds >= 61)
797 return std::numeric_limits<double>::quiet_NaN();
798 if (seconds > 60) {
799 // Discard leap seconds by clamping to the end of a minute.
800 seconds = 60;
801 }
802
803 double dateSeconds = ymdhmsToSeconds(year, month, day, hours, minutes, seconds) - timeZoneSeconds;
804 return dateSeconds * msPerSecond;
805 }
806
807 // Odd case where 'exec' is allowed to be 0, to accomodate a caller in WebCore.
808 double parseDateFromNullTerminatedCharacters(const char* dateString, bool& haveTZ, int& offset)
809 {
810 haveTZ = false;
811 offset = 0;
812
813 // This parses a date in the form:
814 // Tuesday, 09-Nov-99 23:12:40 GMT
815 // or
816 // Sat, 01-Jan-2000 08:00:00 GMT
817 // or
818 // Sat, 01 Jan 2000 08:00:00 GMT
819 // or
820 // 01 Jan 99 22:00 +0100 (exceptions in rfc822/rfc2822)
821 // ### non RFC formats, added for Javascript:
822 // [Wednesday] January 09 1999 23:12:40 GMT
823 // [Wednesday] January 09 23:12:40 GMT 1999
824 //
825 // We ignore the weekday.
826
827 // Skip leading space
828 skipSpacesAndComments(dateString);
829
830 long month = -1;
831 const char *wordStart = dateString;
832 // Check contents of first words if not number
833 while (*dateString && !isASCIIDigit(*dateString)) {
834 if (isASCIISpace(*dateString) || *dateString == '(') {
835 if (dateString - wordStart >= 3)
836 month = findMonth(wordStart);
837 skipSpacesAndComments(dateString);
838 wordStart = dateString;
839 } else
840 dateString++;
841 }
842
843 // Missing delimiter between month and day (like "January29")?
844 if (month == -1 && wordStart != dateString)
845 month = findMonth(wordStart);
846
847 skipSpacesAndComments(dateString);
848
849 if (!*dateString)
850 return std::numeric_limits<double>::quiet_NaN();
851
852 // ' 09-Nov-99 23:12:40 GMT'
853 char* newPosStr;
854 long day;
855 if (!parseLong(dateString, &newPosStr, 10, &day))
856 return std::numeric_limits<double>::quiet_NaN();
857 dateString = newPosStr;
858
859 if (!*dateString)
860 return std::numeric_limits<double>::quiet_NaN();
861
862 if (day < 0)
863 return std::numeric_limits<double>::quiet_NaN();
864
865 int year = 0;
866 if (day > 31) {
867 // ### where is the boundary and what happens below?
868 if (*dateString != '/')
869 return std::numeric_limits<double>::quiet_NaN();
870 // looks like a YYYY/MM/DD date
871 if (!*++dateString)
872 return std::numeric_limits<double>::quiet_NaN();
873 if (day <= std::numeric_limits<int>::min() || day >= std::numeric_limits<int>::max())
874 return std::numeric_limits<double>::quiet_NaN();
875 year = static_cast<int>(day);
876 if (!parseLong(dateString, &newPosStr, 10, &month))
877 return std::numeric_limits<double>::quiet_NaN();
878 month -= 1;
879 dateString = newPosStr;
880 if (*dateString++ != '/' || !*dateString)
881 return std::numeric_limits<double>::quiet_NaN();
882 if (!parseLong(dateString, &newPosStr, 10, &day))
883 return std::numeric_limits<double>::quiet_NaN();
884 dateString = newPosStr;
885 } else if (*dateString == '/' && month == -1) {
886 dateString++;
887 // This looks like a MM/DD/YYYY date, not an RFC date.
888 month = day - 1; // 0-based
889 if (!parseLong(dateString, &newPosStr, 10, &day))
890 return std::numeric_limits<double>::quiet_NaN();
891 if (day < 1 || day > 31)
892 return std::numeric_limits<double>::quiet_NaN();
893 dateString = newPosStr;
894 if (*dateString == '/')
895 dateString++;
896 if (!*dateString)
897 return std::numeric_limits<double>::quiet_NaN();
898 } else {
899 if (*dateString == '-')
900 dateString++;
901
902 skipSpacesAndComments(dateString);
903
904 if (*dateString == ',')
905 dateString++;
906
907 if (month == -1) { // not found yet
908 month = findMonth(dateString);
909 if (month == -1)
910 return std::numeric_limits<double>::quiet_NaN();
911
912 while (*dateString && *dateString != '-' && *dateString != ',' && !isASCIISpace(*dateString))
913 dateString++;
914
915 if (!*dateString)
916 return std::numeric_limits<double>::quiet_NaN();
917
918 // '-99 23:12:40 GMT'
919 if (*dateString != '-' && *dateString != '/' && *dateString != ',' && !isASCIISpace(*dateString))
920 return std::numeric_limits<double>::quiet_NaN();
921 dateString++;
922 }
923 }
924
925 if (month < 0 || month > 11)
926 return std::numeric_limits<double>::quiet_NaN();
927
928 // '99 23:12:40 GMT'
929 if (year <= 0 && *dateString) {
930 if (!parseInt(dateString, &newPosStr, 10, &year))
931 return std::numeric_limits<double>::quiet_NaN();
932 }
933
934 // Don't fail if the time is missing.
935 long hour = 0;
936 long minute = 0;
937 long second = 0;
938 if (!*newPosStr)
939 dateString = newPosStr;
940 else {
941 // ' 23:12:40 GMT'
942 if (!(isASCIISpace(*newPosStr) || *newPosStr == ',')) {
943 if (*newPosStr != ':')
944 return std::numeric_limits<double>::quiet_NaN();
945 // There was no year; the number was the hour.
946 year = -1;
947 } else {
948 // in the normal case (we parsed the year), advance to the next number
949 dateString = ++newPosStr;
950 skipSpacesAndComments(dateString);
951 }
952
953 parseLong(dateString, &newPosStr, 10, &hour);
954 // Do not check for errno here since we want to continue
955 // even if errno was set becasue we are still looking
956 // for the timezone!
957
958 // Read a number? If not, this might be a timezone name.
959 if (newPosStr != dateString) {
960 dateString = newPosStr;
961
962 if (hour < 0 || hour > 23)
963 return std::numeric_limits<double>::quiet_NaN();
964
965 if (!*dateString)
966 return std::numeric_limits<double>::quiet_NaN();
967
968 // ':12:40 GMT'
969 if (*dateString++ != ':')
970 return std::numeric_limits<double>::quiet_NaN();
971
972 if (!parseLong(dateString, &newPosStr, 10, &minute))
973 return std::numeric_limits<double>::quiet_NaN();
974 dateString = newPosStr;
975
976 if (minute < 0 || minute > 59)
977 return std::numeric_limits<double>::quiet_NaN();
978
979 // ':40 GMT'
980 if (*dateString && *dateString != ':' && !isASCIISpace(*dateString))
981 return std::numeric_limits<double>::quiet_NaN();
982
983 // seconds are optional in rfc822 + rfc2822
984 if (*dateString ==':') {
985 dateString++;
986
987 if (!parseLong(dateString, &newPosStr, 10, &second))
988 return std::numeric_limits<double>::quiet_NaN();
989 dateString = newPosStr;
990
991 if (second < 0 || second > 59)
992 return std::numeric_limits<double>::quiet_NaN();
993 }
994
995 skipSpacesAndComments(dateString);
996
997 if (strncasecmp(dateString, "AM", 2) == 0) {
998 if (hour > 12)
999 return std::numeric_limits<double>::quiet_NaN();
1000 if (hour == 12)
1001 hour = 0;
1002 dateString += 2;
1003 skipSpacesAndComments(dateString);
1004 } else if (strncasecmp(dateString, "PM", 2) == 0) {
1005 if (hour > 12)
1006 return std::numeric_limits<double>::quiet_NaN();
1007 if (hour != 12)
1008 hour += 12;
1009 dateString += 2;
1010 skipSpacesAndComments(dateString);
1011 }
1012 }
1013 }
1014
1015 // The year may be after the time but before the time zone.
1016 if (isASCIIDigit(*dateString) && year == -1) {
1017 if (!parseInt(dateString, &newPosStr, 10, &year))
1018 return std::numeric_limits<double>::quiet_NaN();
1019 dateString = newPosStr;
1020 skipSpacesAndComments(dateString);
1021 }
1022
1023 // Don't fail if the time zone is missing.
1024 // Some websites omit the time zone (4275206).
1025 if (*dateString) {
1026 if (strncasecmp(dateString, "GMT", 3) == 0 || strncasecmp(dateString, "UTC", 3) == 0) {
1027 dateString += 3;
1028 haveTZ = true;
1029 }
1030
1031 if (*dateString == '+' || *dateString == '-') {
1032 int o;
1033 if (!parseInt(dateString, &newPosStr, 10, &o))
1034 return std::numeric_limits<double>::quiet_NaN();
1035 dateString = newPosStr;
1036
1037 if (o < -9959 || o > 9959)
1038 return std::numeric_limits<double>::quiet_NaN();
1039
1040 int sgn = (o < 0) ? -1 : 1;
1041 o = abs(o);
1042 if (*dateString != ':') {
1043 if (o >= 24)
1044 offset = ((o / 100) * 60 + (o % 100)) * sgn;
1045 else
1046 offset = o * 60 * sgn;
1047 } else { // GMT+05:00
1048 ++dateString; // skip the ':'
1049 int o2;
1050 if (!parseInt(dateString, &newPosStr, 10, &o2))
1051 return std::numeric_limits<double>::quiet_NaN();
1052 dateString = newPosStr;
1053 offset = (o * 60 + o2) * sgn;
1054 }
1055 haveTZ = true;
1056 } else {
1057 for (size_t i = 0; i < WTF_ARRAY_LENGTH(known_zones); ++i) {
1058 if (0 == strncasecmp(dateString, known_zones[i].tzName, strlen(known_zones[i].tzName))) {
1059 offset = known_zones[i].tzOffset;
1060 dateString += strlen(known_zones[i].tzName);
1061 haveTZ = true;
1062 break;
1063 }
1064 }
1065 }
1066 }
1067
1068 skipSpacesAndComments(dateString);
1069
1070 if (*dateString && year == -1) {
1071 if (!parseInt(dateString, &newPosStr, 10, &year))
1072 return std::numeric_limits<double>::quiet_NaN();
1073 dateString = newPosStr;
1074 skipSpacesAndComments(dateString);
1075 }
1076
1077 // Trailing garbage
1078 if (*dateString)
1079 return std::numeric_limits<double>::quiet_NaN();
1080
1081 // Y2K: Handle 2 digit years.
1082 if (year >= 0 && year < 100) {
1083 if (year < 50)
1084 year += 2000;
1085 else
1086 year += 1900;
1087 }
1088
1089 return ymdhmsToSeconds(year, month + 1, day, hour, minute, second) * msPerSecond;
1090 }
1091
1092 double parseDateFromNullTerminatedCharacters(const char* dateString)
1093 {
1094 bool haveTZ;
1095 int offset;
1096 double ms = parseDateFromNullTerminatedCharacters(dateString, haveTZ, offset);
1097 if (std::isnan(ms))
1098 return std::numeric_limits<double>::quiet_NaN();
1099
1100 // fall back to local timezone
1101 if (!haveTZ)
1102 offset = calculateLocalTimeOffset(ms).offset / msPerMinute;
1103
1104 return ms - (offset * msPerMinute);
1105 }
1106
1107 double timeClip(double t)
1108 {
1109 if (!std::isfinite(t))
1110 return std::numeric_limits<double>::quiet_NaN();
1111 if (fabs(t) > maxECMAScriptTime)
1112 return std::numeric_limits<double>::quiet_NaN();
1113 return trunc(t);
1114 }
1115
1116 // See http://tools.ietf.org/html/rfc2822#section-3.3 for more information.
1117 String makeRFC2822DateString(unsigned dayOfWeek, unsigned day, unsigned month, unsigned year, unsigned hours, unsigned minutes, unsigned seconds, int utcOffset)
1118 {
1119 StringBuilder stringBuilder;
1120 stringBuilder.append(weekdayName[dayOfWeek]);
1121 stringBuilder.appendLiteral(", ");
1122 stringBuilder.appendNumber(day);
1123 stringBuilder.append(' ');
1124 stringBuilder.append(monthName[month]);
1125 stringBuilder.append(' ');
1126 stringBuilder.appendNumber(year);
1127 stringBuilder.append(' ');
1128
1129 appendTwoDigitNumber(stringBuilder, hours);
1130 stringBuilder.append(':');
1131 appendTwoDigitNumber(stringBuilder, minutes);
1132 stringBuilder.append(':');
1133 appendTwoDigitNumber(stringBuilder, seconds);
1134 stringBuilder.append(' ');
1135
1136 stringBuilder.append(utcOffset > 0 ? '+' : '-');
1137 int absoluteUTCOffset = abs(utcOffset);
1138 appendTwoDigitNumber(stringBuilder, absoluteUTCOffset / 60);
1139 appendTwoDigitNumber(stringBuilder, absoluteUTCOffset % 60);
1140
1141 return stringBuilder.toString();
1142 }
1143
1144 } // namespace WTF