1 /* 2 * Copyright (C) 1999-2000 Harri Porten (porten (at) 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 (at) 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(SYS_TIME_H) 94 #include <sys/time.h> 95 #endif 96 97 using namespace WTF; 98 99 namespace WTF { 100 101 /* Constants */ 102 103 static const double minutesPerDay = 24.0 * 60.0; 104 static const double secondsPerDay = 24.0 * 60.0 * 60.0; 105 static const double secondsPerYear = 24.0 * 60.0 * 60.0 * 365.0; 106 107 static const double usecPerSec = 1000000.0; 108 109 static const double maxUnixTime = 2145859200.0; // 12/31/2037 110 // ECMAScript asks not to support for a date of which total 111 // millisecond value is larger than the following value. 112 // See 15.9.1.14 of ECMA-262 5th edition. 113 static const double maxECMAScriptTime = 8.64E15; 114 115 // Day of year for the first day of each month, where index 0 is January, and day 0 is January 1. 116 // First for non-leap years, then for leap years. 117 static const int firstDayOfMonth[2][12] = { 118 {0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334}, 119 {0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335} 120 }; 121 122 static inline void getLocalTime(const time_t* localTime, struct tm* localTM) 123 { 124 #if COMPILER(MSVC) 125 localtime_s(localTM, localTime); 126 #else 127 localtime_r(localTime, localTM); 128 #endif 129 } 130 131 bool isLeapYear(int year) 132 { 133 if (year % 4 != 0) 134 return false; 135 if (year % 400 == 0) 136 return true; 137 if (year % 100 == 0) 138 return false; 139 return true; 140 } 141 142 static inline int daysInYear(int year) 143 { 144 return 365 + isLeapYear(year); 145 } 146 147 static inline double daysFrom1970ToYear(int year) 148 { 149 // The Gregorian Calendar rules for leap years: 150 // Every fourth year is a leap year. 2004, 2008, and 2012 are leap years. 151 // However, every hundredth year is not a leap year. 1900 and 2100 are not leap years. 152 // Every four hundred years, there's a leap year after all. 2000 and 2400 are leap years. 153 154 static const int leapDaysBefore1971By4Rule = 1970 / 4; 155 static const int excludedLeapDaysBefore1971By100Rule = 1970 / 100; 156 static const int leapDaysBefore1971By400Rule = 1970 / 400; 157 158 const double yearMinusOne = year - 1; 159 const double yearsToAddBy4Rule = floor(yearMinusOne / 4.0) - leapDaysBefore1971By4Rule; 160 const double yearsToExcludeBy100Rule = floor(yearMinusOne / 100.0) - excludedLeapDaysBefore1971By100Rule; 161 const double yearsToAddBy400Rule = floor(yearMinusOne / 400.0) - leapDaysBefore1971By400Rule; 162 163 return 365.0 * (year - 1970) + yearsToAddBy4Rule - yearsToExcludeBy100Rule + yearsToAddBy400Rule; 164 } 165 166 double msToDays(double ms) 167 { 168 return floor(ms / msPerDay); 169 } 170 171 static String twoDigitStringFromNumber(int number) 172 { 173 ASSERT(number >= 0 && number < 100); 174 if (number > 9) 175 return String::number(number); 176 return "0" + String::number(number); 177 } 178 179 int msToYear(double ms) 180 { 181 int approxYear = static_cast<int>(floor(ms / (msPerDay * 365.2425)) + 1970); 182 double msFromApproxYearTo1970 = msPerDay * daysFrom1970ToYear(approxYear); 183 if (msFromApproxYearTo1970 > ms) 184 return approxYear - 1; 185 if (msFromApproxYearTo1970 + msPerDay * daysInYear(approxYear) <= ms) 186 return approxYear + 1; 187 return approxYear; 188 } 189 190 int dayInYear(double ms, int year) 191 { 192 return static_cast<int>(msToDays(ms) - daysFrom1970ToYear(year)); 193 } 194 195 static inline double msToMilliseconds(double ms) 196 { 197 double result = fmod(ms, msPerDay); 198 if (result < 0) 199 result += msPerDay; 200 return result; 201 } 202 203 int msToMinutes(double ms) 204 { 205 double result = fmod(floor(ms / msPerMinute), minutesPerHour); 206 if (result < 0) 207 result += minutesPerHour; 208 return static_cast<int>(result); 209 } 210 211 int msToHours(double ms) 212 { 213 double result = fmod(floor(ms/msPerHour), hoursPerDay); 214 if (result < 0) 215 result += hoursPerDay; 216 return static_cast<int>(result); 217 } 218 219 int monthFromDayInYear(int dayInYear, bool leapYear) 220 { 221 const int d = dayInYear; 222 int step; 223 224 if (d < (step = 31)) 225 return 0; 226 step += (leapYear ? 29 : 28); 227 if (d < step) 228 return 1; 229 if (d < (step += 31)) 230 return 2; 231 if (d < (step += 30)) 232 return 3; 233 if (d < (step += 31)) 234 return 4; 235 if (d < (step += 30)) 236 return 5; 237 if (d < (step += 31)) 238 return 6; 239 if (d < (step += 31)) 240 return 7; 241 if (d < (step += 30)) 242 return 8; 243 if (d < (step += 31)) 244 return 9; 245 if (d < (step += 30)) 246 return 10; 247 return 11; 248 } 249 250 static inline bool checkMonth(int dayInYear, int& startDayOfThisMonth, int& startDayOfNextMonth, int daysInThisMonth) 251 { 252 startDayOfThisMonth = startDayOfNextMonth; 253 startDayOfNextMonth += daysInThisMonth; 254 return (dayInYear <= startDayOfNextMonth); 255 } 256 257 int dayInMonthFromDayInYear(int dayInYear, bool leapYear) 258 { 259 const int d = dayInYear; 260 int step; 261 int next = 30; 262 263 if (d <= next) 264 return d + 1; 265 const int daysInFeb = (leapYear ? 29 : 28); 266 if (checkMonth(d, step, next, daysInFeb)) 267 return d - step; 268 if (checkMonth(d, step, next, 31)) 269 return d - step; 270 if (checkMonth(d, step, next, 30)) 271 return d - step; 272 if (checkMonth(d, step, next, 31)) 273 return d - step; 274 if (checkMonth(d, step, next, 30)) 275 return d - step; 276 if (checkMonth(d, step, next, 31)) 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, 30)) 285 return d - step; 286 step = next; 287 return d - step; 288 } 289 290 int dayInYear(int year, int month, int day) 291 { 292 return firstDayOfMonth[isLeapYear(year)][month] + day - 1; 293 } 294 295 double dateToDaysFrom1970(int year, int month, int day) 296 { 297 year += month / 12; 298 299 month %= 12; 300 if (month < 0) { 301 month += 12; 302 --year; 303 } 304 305 double yearday = floor(daysFrom1970ToYear(year)); 306 ASSERT((year >= 1970 && yearday >= 0) || (year < 1970 && yearday < 0)); 307 return yearday + dayInYear(year, month, day); 308 } 309 310 // There is a hard limit at 2038 that we currently do not have a workaround 311 // for (rdar://problem/5052975). 312 static inline int maximumYearForDST() 313 { 314 return 2037; 315 } 316 317 static inline int minimumYearForDST() 318 { 319 // Because of the 2038 issue (see maximumYearForDST) if the current year is 320 // greater than the max year minus 27 (2010), we want to use the max year 321 // minus 27 instead, to ensure there is a range of 28 years that all years 322 // can map to. 323 return std::min(msToYear(jsCurrentTime()), maximumYearForDST() - 27) ; 324 } 325 326 /* 327 * Find an equivalent year for the one given, where equivalence is deterined by 328 * the two years having the same leapness and the first day of the year, falling 329 * on the same day of the week. 330 * 331 * This function returns a year between this current year and 2037, however this 332 * function will potentially return incorrect results if the current year is after 333 * 2010, (rdar://problem/5052975), if the year passed in is before 1900 or after 334 * 2100, (rdar://problem/5055038). 335 */ 336 int equivalentYearForDST(int year) 337 { 338 // It is ok if the cached year is not the current year as long as the rules 339 // for DST did not change between the two years; if they did the app would need 340 // to be restarted. 341 static int minYear = minimumYearForDST(); 342 int maxYear = maximumYearForDST(); 343 344 int difference; 345 if (year > maxYear) 346 difference = minYear - year; 347 else if (year < minYear) 348 difference = maxYear - year; 349 else 350 return year; 351 352 int quotient = difference / 28; 353 int product = (quotient) * 28; 354 355 year += product; 356 ASSERT((year >= minYear && year <= maxYear) || (product - year == static_cast<int>(std::numeric_limits<double>::quiet_NaN()))); 357 return year; 358 } 359 360 int32_t calculateUTCOffset() 361 { 362 #if OS(WINDOWS) 363 TIME_ZONE_INFORMATION timeZoneInformation; 364 GetTimeZoneInformation(&timeZoneInformation); 365 int32_t bias = timeZoneInformation.Bias + timeZoneInformation.StandardBias; 366 return -bias * 60 * 1000; 367 #else 368 time_t localTime = time(0); 369 tm localt; 370 getLocalTime(&localTime, &localt); 371 372 // Get the difference between this time zone and UTC on the 1st of January of this year. 373 localt.tm_sec = 0; 374 localt.tm_min = 0; 375 localt.tm_hour = 0; 376 localt.tm_mday = 1; 377 localt.tm_mon = 0; 378 // Not setting localt.tm_year! 379 localt.tm_wday = 0; 380 localt.tm_yday = 0; 381 localt.tm_isdst = 0; 382 #if HAVE(TM_GMTOFF) 383 localt.tm_gmtoff = 0; 384 #endif 385 #if HAVE(TM_ZONE) 386 localt.tm_zone = 0; 387 #endif 388 389 #if HAVE(TIMEGM) 390 time_t utcOffset = timegm(&localt) - mktime(&localt); 391 #else 392 // Using a canned date of 01/01/2009 on platforms with weaker date-handling foo. 393 localt.tm_year = 109; 394 time_t utcOffset = 1230768000 - mktime(&localt); 395 #endif 396 397 return static_cast<int32_t>(utcOffset * 1000); 398 #endif 399 } 400 401 /* 402 * Get the DST offset for the time passed in. 403 */ 404 static double calculateDSTOffsetSimple(double localTimeSeconds, double utcOffset) 405 { 406 if (localTimeSeconds > maxUnixTime) 407 localTimeSeconds = maxUnixTime; 408 else if (localTimeSeconds < 0) // Go ahead a day to make localtime work (does not work with 0) 409 localTimeSeconds += secondsPerDay; 410 411 //input is UTC so we have to shift back to local time to determine DST thus the + getUTCOffset() 412 double offsetTime = (localTimeSeconds * msPerSecond) + utcOffset; 413 414 // Offset from UTC but doesn't include DST obviously 415 int offsetHour = msToHours(offsetTime); 416 int offsetMinute = msToMinutes(offsetTime); 417 418 // FIXME: time_t has a potential problem in 2038 419 time_t localTime = static_cast<time_t>(localTimeSeconds); 420 421 tm localTM; 422 getLocalTime(&localTime, &localTM); 423 424 double diff = ((localTM.tm_hour - offsetHour) * secondsPerHour) + ((localTM.tm_min - offsetMinute) * 60); 425 426 if (diff < 0) 427 diff += secondsPerDay; 428 429 return (diff * msPerSecond); 430 } 431 432 // Get the DST offset, given a time in UTC 433 double calculateDSTOffset(double ms, double utcOffset) 434 { 435 // On Mac OS X, the call to localtime (see calculateDSTOffsetSimple) will return historically accurate 436 // DST information (e.g. New Zealand did not have DST from 1946 to 1974) however the JavaScript 437 // standard explicitly dictates that historical information should not be considered when 438 // determining DST. For this reason we shift away from years that localtime can handle but would 439 // return historically accurate information. 440 int year = msToYear(ms); 441 int equivalentYear = equivalentYearForDST(year); 442 if (year != equivalentYear) { 443 bool leapYear = isLeapYear(year); 444 int dayInYearLocal = dayInYear(ms, year); 445 int dayInMonth = dayInMonthFromDayInYear(dayInYearLocal, leapYear); 446 int month = monthFromDayInYear(dayInYearLocal, leapYear); 447 double day = dateToDaysFrom1970(equivalentYear, month, dayInMonth); 448 ms = (day * msPerDay) + msToMilliseconds(ms); 449 } 450 451 return calculateDSTOffsetSimple(ms / msPerSecond, utcOffset); 452 } 453 454 void initializeDates() 455 { 456 #if !ASSERT_DISABLED 457 static bool alreadyInitialized; 458 ASSERT(!alreadyInitialized); 459 alreadyInitialized = true; 460 #endif 461 462 equivalentYearForDST(2000); // Need to call once to initialize a static used in this function. 463 } 464 465 static inline double ymdhmsToSeconds(int year, long mon, long day, long hour, long minute, double second) 466 { 467 double days = (day - 32075) 468 + floor(1461 * (year + 4800.0 + (mon - 14) / 12) / 4) 469 + 367 * (mon - 2 - (mon - 14) / 12 * 12) / 12 470 - floor(3 * ((year + 4900.0 + (mon - 14) / 12) / 100) / 4) 471 - 2440588; 472 return ((days * hoursPerDay + hour) * minutesPerHour + minute) * secondsPerMinute + second; 473 } 474 475 // We follow the recommendation of RFC 2822 to consider all 476 // obsolete time zones not listed here equivalent to "-0000". 477 static const struct KnownZone { 478 #if !OS(WINDOWS) 479 const 480 #endif 481 char tzName[4]; 482 int tzOffset; 483 } known_zones[] = { 484 { "UT", 0 }, 485 { "GMT", 0 }, 486 { "EST", -300 }, 487 { "EDT", -240 }, 488 { "CST", -360 }, 489 { "CDT", -300 }, 490 { "MST", -420 }, 491 { "MDT", -360 }, 492 { "PST", -480 }, 493 { "PDT", -420 } 494 }; 495 496 inline static void skipSpacesAndComments(const char*& s) 497 { 498 int nesting = 0; 499 char ch; 500 while ((ch = *s)) { 501 if (!isASCIISpace(ch)) { 502 if (ch == '(') 503 nesting++; 504 else if (ch == ')' && nesting > 0) 505 nesting--; 506 else if (nesting == 0) 507 break; 508 } 509 s++; 510 } 511 } 512 513 // returns 0-11 (Jan-Dec); -1 on failure 514 static int findMonth(const char* monthStr) 515 { 516 ASSERT(monthStr); 517 char needle[4]; 518 for (int i = 0; i < 3; ++i) { 519 if (!*monthStr) 520 return -1; 521 needle[i] = static_cast<char>(toASCIILower(*monthStr++)); 522 } 523 needle[3] = '\0'; 524 const char *haystack = "janfebmaraprmayjunjulaugsepoctnovdec"; 525 const char *str = strstr(haystack, needle); 526 if (str) { 527 int position = static_cast<int>(str - haystack); 528 if (position % 3 == 0) 529 return position / 3; 530 } 531 return -1; 532 } 533 534 static bool parseInt(const char* string, char** stopPosition, int base, int* result) 535 { 536 long longResult = strtol(string, stopPosition, base); 537 // Avoid the use of errno as it is not available on Windows CE 538 if (string == *stopPosition || longResult <= std::numeric_limits<int>::min() || longResult >= std::numeric_limits<int>::max()) 539 return false; 540 *result = static_cast<int>(longResult); 541 return true; 542 } 543 544 static bool parseLong(const char* string, char** stopPosition, int base, long* result) 545 { 546 *result = strtol(string, stopPosition, base); 547 // Avoid the use of errno as it is not available on Windows CE 548 if (string == *stopPosition || *result == std::numeric_limits<long>::min() || *result == std::numeric_limits<long>::max()) 549 return false; 550 return true; 551 } 552 553 // Parses a date with the format YYYY[-MM[-DD]]. 554 // Year parsing is lenient, allows any number of digits, and +/-. 555 // Returns 0 if a parse error occurs, else returns the end of the parsed portion of the string. 556 static char* parseES5DatePortion(const char* currentPosition, int& year, long& month, long& day) 557 { 558 char* postParsePosition; 559 560 // This is a bit more lenient on the year string than ES5 specifies: 561 // instead of restricting to 4 digits (or 6 digits with mandatory +/-), 562 // it accepts any integer value. Consider this an implementation fallback. 563 if (!parseInt(currentPosition, &postParsePosition, 10, &year)) 564 return 0; 565 566 // Check for presence of -MM portion. 567 if (*postParsePosition != '-') 568 return postParsePosition; 569 currentPosition = postParsePosition + 1; 570 571 if (!isASCIIDigit(*currentPosition)) 572 return 0; 573 if (!parseLong(currentPosition, &postParsePosition, 10, &month)) 574 return 0; 575 if ((postParsePosition - currentPosition) != 2) 576 return 0; 577 578 // Check for presence of -DD portion. 579 if (*postParsePosition != '-') 580 return postParsePosition; 581 currentPosition = postParsePosition + 1; 582 583 if (!isASCIIDigit(*currentPosition)) 584 return 0; 585 if (!parseLong(currentPosition, &postParsePosition, 10, &day)) 586 return 0; 587 if ((postParsePosition - currentPosition) != 2) 588 return 0; 589 return postParsePosition; 590 } 591 592 // Parses a time with the format HH:mm[:ss[.sss]][Z|(+|-)00:00]. 593 // Fractional seconds parsing is lenient, allows any number of digits. 594 // Returns 0 if a parse error occurs, else returns the end of the parsed portion of the string. 595 static char* parseES5TimePortion(char* currentPosition, long& hours, long& minutes, double& seconds, long& timeZoneSeconds) 596 { 597 char* postParsePosition; 598 if (!isASCIIDigit(*currentPosition)) 599 return 0; 600 if (!parseLong(currentPosition, &postParsePosition, 10, &hours)) 601 return 0; 602 if (*postParsePosition != ':' || (postParsePosition - currentPosition) != 2) 603 return 0; 604 currentPosition = postParsePosition + 1; 605 606 if (!isASCIIDigit(*currentPosition)) 607 return 0; 608 if (!parseLong(currentPosition, &postParsePosition, 10, &minutes)) 609 return 0; 610 if ((postParsePosition - currentPosition) != 2) 611 return 0; 612 currentPosition = postParsePosition; 613 614 // Seconds are optional. 615 if (*currentPosition == ':') { 616 ++currentPosition; 617 618 long intSeconds; 619 if (!isASCIIDigit(*currentPosition)) 620 return 0; 621 if (!parseLong(currentPosition, &postParsePosition, 10, &intSeconds)) 622 return 0; 623 if ((postParsePosition - currentPosition) != 2) 624 return 0; 625 seconds = intSeconds; 626 if (*postParsePosition == '.') { 627 currentPosition = postParsePosition + 1; 628 629 // In ECMA-262-5 it's a bit unclear if '.' can be present without milliseconds, but 630 // a reasonable interpretation guided by the given examples and RFC 3339 says "no". 631 // We check the next character to avoid reading +/- timezone hours after an invalid decimal. 632 if (!isASCIIDigit(*currentPosition)) 633 return 0; 634 635 // We are more lenient than ES5 by accepting more or less than 3 fraction digits. 636 long fracSeconds; 637 if (!parseLong(currentPosition, &postParsePosition, 10, &fracSeconds)) 638 return 0; 639 640 long numFracDigits = postParsePosition - currentPosition; 641 seconds += fracSeconds * pow(10.0, static_cast<double>(-numFracDigits)); 642 } 643 currentPosition = postParsePosition; 644 } 645 646 if (*currentPosition == 'Z') 647 return currentPosition + 1; 648 649 bool tzNegative; 650 if (*currentPosition == '-') 651 tzNegative = true; 652 else if (*currentPosition == '+') 653 tzNegative = false; 654 else 655 return currentPosition; // no timezone 656 ++currentPosition; 657 658 long tzHours; 659 long tzHoursAbs; 660 long tzMinutes; 661 662 if (!isASCIIDigit(*currentPosition)) 663 return 0; 664 if (!parseLong(currentPosition, &postParsePosition, 10, &tzHours)) 665 return 0; 666 if (*postParsePosition != ':' || (postParsePosition - currentPosition) != 2) 667 return 0; 668 tzHoursAbs = labs(tzHours); 669 currentPosition = postParsePosition + 1; 670 671 if (!isASCIIDigit(*currentPosition)) 672 return 0; 673 if (!parseLong(currentPosition, &postParsePosition, 10, &tzMinutes)) 674 return 0; 675 if ((postParsePosition - currentPosition) != 2) 676 return 0; 677 currentPosition = postParsePosition; 678 679 if (tzHoursAbs > 24) 680 return 0; 681 if (tzMinutes < 0 || tzMinutes > 59) 682 return 0; 683 684 timeZoneSeconds = 60 * (tzMinutes + (60 * tzHoursAbs)); 685 if (tzNegative) 686 timeZoneSeconds = -timeZoneSeconds; 687 688 return currentPosition; 689 } 690 691 double parseES5DateFromNullTerminatedCharacters(const char* dateString) 692 { 693 // This parses a date of the form defined in ECMA-262-5, section 15.9.1.15 694 // (similar to RFC 3339 / ISO 8601: YYYY-MM-DDTHH:mm:ss[.sss]Z). 695 // In most cases it is intentionally strict (e.g. correct field widths, no stray whitespace). 696 697 static const long daysPerMonth[12] = { 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }; 698 699 // The year must be present, but the other fields may be omitted - see ES5.1 15.9.1.15. 700 int year = 0; 701 long month = 1; 702 long day = 1; 703 long hours = 0; 704 long minutes = 0; 705 double seconds = 0; 706 long timeZoneSeconds = 0; 707 708 // Parse the date YYYY[-MM[-DD]] 709 char* currentPosition = parseES5DatePortion(dateString, year, month, day); 710 if (!currentPosition) 711 return std::numeric_limits<double>::quiet_NaN(); 712 // Look for a time portion. 713 if (*currentPosition == 'T') { 714 // Parse the time HH:mm[:ss[.sss]][Z|(+|-)00:00] 715 currentPosition = parseES5TimePortion(currentPosition + 1, hours, minutes, seconds, timeZoneSeconds); 716 if (!currentPosition) 717 return std::numeric_limits<double>::quiet_NaN(); 718 } 719 // Check that we have parsed all characters in the string. 720 if (*currentPosition) 721 return std::numeric_limits<double>::quiet_NaN(); 722 723 // A few of these checks could be done inline above, but since many of them are interrelated 724 // we would be sacrificing readability to "optimize" the (presumably less common) failure path. 725 if (month < 1 || month > 12) 726 return std::numeric_limits<double>::quiet_NaN(); 727 if (day < 1 || day > daysPerMonth[month - 1]) 728 return std::numeric_limits<double>::quiet_NaN(); 729 if (month == 2 && day > 28 && !isLeapYear(year)) 730 return std::numeric_limits<double>::quiet_NaN(); 731 if (hours < 0 || hours > 24) 732 return std::numeric_limits<double>::quiet_NaN(); 733 if (hours == 24 && (minutes || seconds)) 734 return std::numeric_limits<double>::quiet_NaN(); 735 if (minutes < 0 || minutes > 59) 736 return std::numeric_limits<double>::quiet_NaN(); 737 if (seconds < 0 || seconds >= 61) 738 return std::numeric_limits<double>::quiet_NaN(); 739 if (seconds > 60) { 740 // Discard leap seconds by clamping to the end of a minute. 741 seconds = 60; 742 } 743 744 double dateSeconds = ymdhmsToSeconds(year, month, day, hours, minutes, seconds) - timeZoneSeconds; 745 return dateSeconds * msPerSecond; 746 } 747 748 // Odd case where 'exec' is allowed to be 0, to accomodate a caller in WebCore. 749 double parseDateFromNullTerminatedCharacters(const char* dateString, bool& haveTZ, int& offset) 750 { 751 haveTZ = false; 752 offset = 0; 753 754 // This parses a date in the form: 755 // Tuesday, 09-Nov-99 23:12:40 GMT 756 // or 757 // Sat, 01-Jan-2000 08:00:00 GMT 758 // or 759 // Sat, 01 Jan 2000 08:00:00 GMT 760 // or 761 // 01 Jan 99 22:00 +0100 (exceptions in rfc822/rfc2822) 762 // ### non RFC formats, added for Javascript: 763 // [Wednesday] January 09 1999 23:12:40 GMT 764 // [Wednesday] January 09 23:12:40 GMT 1999 765 // 766 // We ignore the weekday. 767 768 // Skip leading space 769 skipSpacesAndComments(dateString); 770 771 long month = -1; 772 const char *wordStart = dateString; 773 // Check contents of first words if not number 774 while (*dateString && !isASCIIDigit(*dateString)) { 775 if (isASCIISpace(*dateString) || *dateString == '(') { 776 if (dateString - wordStart >= 3) 777 month = findMonth(wordStart); 778 skipSpacesAndComments(dateString); 779 wordStart = dateString; 780 } else 781 dateString++; 782 } 783 784 // Missing delimiter between month and day (like "January29")? 785 if (month == -1 && wordStart != dateString) 786 month = findMonth(wordStart); 787 788 skipSpacesAndComments(dateString); 789 790 if (!*dateString) 791 return std::numeric_limits<double>::quiet_NaN(); 792 793 // ' 09-Nov-99 23:12:40 GMT' 794 char* newPosStr; 795 long day; 796 if (!parseLong(dateString, &newPosStr, 10, &day)) 797 return std::numeric_limits<double>::quiet_NaN(); 798 dateString = newPosStr; 799 800 if (!*dateString) 801 return std::numeric_limits<double>::quiet_NaN(); 802 803 if (day < 0) 804 return std::numeric_limits<double>::quiet_NaN(); 805 806 int year = 0; 807 if (day > 31) { 808 // ### where is the boundary and what happens below? 809 if (*dateString != '/') 810 return std::numeric_limits<double>::quiet_NaN(); 811 // looks like a YYYY/MM/DD date 812 if (!*++dateString) 813 return std::numeric_limits<double>::quiet_NaN(); 814 if (day <= std::numeric_limits<int>::min() || day >= std::numeric_limits<int>::max()) 815 return std::numeric_limits<double>::quiet_NaN(); 816 year = static_cast<int>(day); 817 if (!parseLong(dateString, &newPosStr, 10, &month)) 818 return std::numeric_limits<double>::quiet_NaN(); 819 month -= 1; 820 dateString = newPosStr; 821 if (*dateString++ != '/' || !*dateString) 822 return std::numeric_limits<double>::quiet_NaN(); 823 if (!parseLong(dateString, &newPosStr, 10, &day)) 824 return std::numeric_limits<double>::quiet_NaN(); 825 dateString = newPosStr; 826 } else if (*dateString == '/' && month == -1) { 827 dateString++; 828 // This looks like a MM/DD/YYYY date, not an RFC date. 829 month = day - 1; // 0-based 830 if (!parseLong(dateString, &newPosStr, 10, &day)) 831 return std::numeric_limits<double>::quiet_NaN(); 832 if (day < 1 || day > 31) 833 return std::numeric_limits<double>::quiet_NaN(); 834 dateString = newPosStr; 835 if (*dateString == '/') 836 dateString++; 837 if (!*dateString) 838 return std::numeric_limits<double>::quiet_NaN(); 839 } else { 840 if (*dateString == '-') 841 dateString++; 842 843 skipSpacesAndComments(dateString); 844 845 if (*dateString == ',') 846 dateString++; 847 848 if (month == -1) { // not found yet 849 month = findMonth(dateString); 850 if (month == -1) 851 return std::numeric_limits<double>::quiet_NaN(); 852 853 while (*dateString && *dateString != '-' && *dateString != ',' && !isASCIISpace(*dateString)) 854 dateString++; 855 856 if (!*dateString) 857 return std::numeric_limits<double>::quiet_NaN(); 858 859 // '-99 23:12:40 GMT' 860 if (*dateString != '-' && *dateString != '/' && *dateString != ',' && !isASCIISpace(*dateString)) 861 return std::numeric_limits<double>::quiet_NaN(); 862 dateString++; 863 } 864 } 865 866 if (month < 0 || month > 11) 867 return std::numeric_limits<double>::quiet_NaN(); 868 869 // '99 23:12:40 GMT' 870 if (year <= 0 && *dateString) { 871 if (!parseInt(dateString, &newPosStr, 10, &year)) 872 return std::numeric_limits<double>::quiet_NaN(); 873 } 874 875 // Don't fail if the time is missing. 876 long hour = 0; 877 long minute = 0; 878 long second = 0; 879 if (!*newPosStr) 880 dateString = newPosStr; 881 else { 882 // ' 23:12:40 GMT' 883 if (!(isASCIISpace(*newPosStr) || *newPosStr == ',')) { 884 if (*newPosStr != ':') 885 return std::numeric_limits<double>::quiet_NaN(); 886 // There was no year; the number was the hour. 887 year = -1; 888 } else { 889 // in the normal case (we parsed the year), advance to the next number 890 dateString = ++newPosStr; 891 skipSpacesAndComments(dateString); 892 } 893 894 parseLong(dateString, &newPosStr, 10, &hour); 895 // Do not check for errno here since we want to continue 896 // even if errno was set becasue we are still looking 897 // for the timezone! 898 899 // Read a number? If not, this might be a timezone name. 900 if (newPosStr != dateString) { 901 dateString = newPosStr; 902 903 if (hour < 0 || hour > 23) 904 return std::numeric_limits<double>::quiet_NaN(); 905 906 if (!*dateString) 907 return std::numeric_limits<double>::quiet_NaN(); 908 909 // ':12:40 GMT' 910 if (*dateString++ != ':') 911 return std::numeric_limits<double>::quiet_NaN(); 912 913 if (!parseLong(dateString, &newPosStr, 10, &minute)) 914 return std::numeric_limits<double>::quiet_NaN(); 915 dateString = newPosStr; 916 917 if (minute < 0 || minute > 59) 918 return std::numeric_limits<double>::quiet_NaN(); 919 920 // ':40 GMT' 921 if (*dateString && *dateString != ':' && !isASCIISpace(*dateString)) 922 return std::numeric_limits<double>::quiet_NaN(); 923 924 // seconds are optional in rfc822 + rfc2822 925 if (*dateString ==':') { 926 dateString++; 927 928 if (!parseLong(dateString, &newPosStr, 10, &second)) 929 return std::numeric_limits<double>::quiet_NaN(); 930 dateString = newPosStr; 931 932 if (second < 0 || second > 59) 933 return std::numeric_limits<double>::quiet_NaN(); 934 } 935 936 skipSpacesAndComments(dateString); 937 938 if (strncasecmp(dateString, "AM", 2) == 0) { 939 if (hour > 12) 940 return std::numeric_limits<double>::quiet_NaN(); 941 if (hour == 12) 942 hour = 0; 943 dateString += 2; 944 skipSpacesAndComments(dateString); 945 } else if (strncasecmp(dateString, "PM", 2) == 0) { 946 if (hour > 12) 947 return std::numeric_limits<double>::quiet_NaN(); 948 if (hour != 12) 949 hour += 12; 950 dateString += 2; 951 skipSpacesAndComments(dateString); 952 } 953 } 954 } 955 956 // The year may be after the time but before the time zone. 957 if (isASCIIDigit(*dateString) && year == -1) { 958 if (!parseInt(dateString, &newPosStr, 10, &year)) 959 return std::numeric_limits<double>::quiet_NaN(); 960 dateString = newPosStr; 961 skipSpacesAndComments(dateString); 962 } 963 964 // Don't fail if the time zone is missing. 965 // Some websites omit the time zone (4275206). 966 if (*dateString) { 967 if (strncasecmp(dateString, "GMT", 3) == 0 || strncasecmp(dateString, "UTC", 3) == 0) { 968 dateString += 3; 969 haveTZ = true; 970 } 971 972 if (*dateString == '+' || *dateString == '-') { 973 int o; 974 if (!parseInt(dateString, &newPosStr, 10, &o)) 975 return std::numeric_limits<double>::quiet_NaN(); 976 dateString = newPosStr; 977 978 if (o < -9959 || o > 9959) 979 return std::numeric_limits<double>::quiet_NaN(); 980 981 int sgn = (o < 0) ? -1 : 1; 982 o = abs(o); 983 if (*dateString != ':') { 984 if (o >= 24) 985 offset = ((o / 100) * 60 + (o % 100)) * sgn; 986 else 987 offset = o * 60 * sgn; 988 } else { // GMT+05:00 989 ++dateString; // skip the ':' 990 int o2; 991 if (!parseInt(dateString, &newPosStr, 10, &o2)) 992 return std::numeric_limits<double>::quiet_NaN(); 993 dateString = newPosStr; 994 offset = (o * 60 + o2) * sgn; 995 } 996 haveTZ = true; 997 } else { 998 for (size_t i = 0; i < WTF_ARRAY_LENGTH(known_zones); ++i) { 999 if (0 == strncasecmp(dateString, known_zones[i].tzName, strlen(known_zones[i].tzName))) { 1000 offset = known_zones[i].tzOffset; 1001 dateString += strlen(known_zones[i].tzName); 1002 haveTZ = true; 1003 break; 1004 } 1005 } 1006 } 1007 } 1008 1009 skipSpacesAndComments(dateString); 1010 1011 if (*dateString && year == -1) { 1012 if (!parseInt(dateString, &newPosStr, 10, &year)) 1013 return std::numeric_limits<double>::quiet_NaN(); 1014 dateString = newPosStr; 1015 skipSpacesAndComments(dateString); 1016 } 1017 1018 // Trailing garbage 1019 if (*dateString) 1020 return std::numeric_limits<double>::quiet_NaN(); 1021 1022 // Y2K: Handle 2 digit years. 1023 if (year >= 0 && year < 100) { 1024 if (year < 50) 1025 year += 2000; 1026 else 1027 year += 1900; 1028 } 1029 1030 return ymdhmsToSeconds(year, month + 1, day, hour, minute, second) * msPerSecond; 1031 } 1032 1033 double parseDateFromNullTerminatedCharacters(const char* dateString) 1034 { 1035 bool haveTZ; 1036 int offset; 1037 double ms = parseDateFromNullTerminatedCharacters(dateString, haveTZ, offset); 1038 if (std::isnan(ms)) 1039 return std::numeric_limits<double>::quiet_NaN(); 1040 1041 // fall back to local timezone 1042 if (!haveTZ) { 1043 double utcOffset = calculateUTCOffset(); 1044 double dstOffset = calculateDSTOffset(ms, utcOffset); 1045 offset = (utcOffset + dstOffset) / msPerMinute; 1046 } 1047 return ms - (offset * msPerMinute); 1048 } 1049 1050 double timeClip(double t) 1051 { 1052 if (!std::isfinite(t)) 1053 return std::numeric_limits<double>::quiet_NaN(); 1054 if (fabs(t) > maxECMAScriptTime) 1055 return std::numeric_limits<double>::quiet_NaN(); 1056 return trunc(t); 1057 } 1058 1059 // See http://tools.ietf.org/html/rfc2822#section-3.3 for more information. 1060 String makeRFC2822DateString(unsigned dayOfWeek, unsigned day, unsigned month, unsigned year, unsigned hours, unsigned minutes, unsigned seconds, int utcOffset) 1061 { 1062 StringBuilder stringBuilder; 1063 stringBuilder.append(weekdayName[dayOfWeek]); 1064 stringBuilder.appendLiteral(", "); 1065 stringBuilder.appendNumber(day); 1066 stringBuilder.append(' '); 1067 stringBuilder.append(monthName[month]); 1068 stringBuilder.append(' '); 1069 stringBuilder.appendNumber(year); 1070 stringBuilder.append(' '); 1071 1072 stringBuilder.append(twoDigitStringFromNumber(hours)); 1073 stringBuilder.append(':'); 1074 stringBuilder.append(twoDigitStringFromNumber(minutes)); 1075 stringBuilder.append(':'); 1076 stringBuilder.append(twoDigitStringFromNumber(seconds)); 1077 stringBuilder.append(' '); 1078 1079 stringBuilder.append(utcOffset > 0 ? '+' : '-'); 1080 int absoluteUTCOffset = abs(utcOffset); 1081 stringBuilder.append(twoDigitStringFromNumber(absoluteUTCOffset / 60)); 1082 stringBuilder.append(twoDigitStringFromNumber(absoluteUTCOffset % 60)); 1083 1084 return stringBuilder.toString(); 1085 } 1086 1087 } // namespace WTF 1088