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 <math.h> 86 #include <stdlib.h> 87 #include <time.h> 88 #include "wtf/text/StringBuilder.h" 89 90 #if OS(WIN) 91 #include <windows.h> 92 #endif 93 94 #if HAVE(SYS_TIME_H) 95 #include <sys/time.h> 96 #endif 97 98 using namespace WTF; 99 100 namespace WTF { 101 102 /* Constants */ 103 104 static const double hoursPerDay = 24.0; 105 static const double secondsPerDay = 24.0 * 60.0 * 60.0; 106 107 static const double maxUnixTime = 2145859200.0; // 12/31/2037 108 109 // Day of year for the first day of each month, where index 0 is January, and day 0 is January 1. 110 // First for non-leap years, then for leap years. 111 static const int firstDayOfMonth[2][12] = { 112 {0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334}, 113 {0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335} 114 }; 115 116 static inline void getLocalTime(const time_t* localTime, struct tm* localTM) 117 { 118 #if COMPILER(MSVC) 119 localtime_s(localTM, localTime); 120 #else 121 localtime_r(localTime, localTM); 122 #endif 123 } 124 125 bool isLeapYear(int year) 126 { 127 if (year % 4 != 0) 128 return false; 129 if (year % 400 == 0) 130 return true; 131 if (year % 100 == 0) 132 return false; 133 return true; 134 } 135 136 static inline int daysInYear(int year) 137 { 138 return 365 + isLeapYear(year); 139 } 140 141 static inline double daysFrom1970ToYear(int year) 142 { 143 // The Gregorian Calendar rules for leap years: 144 // Every fourth year is a leap year. 2004, 2008, and 2012 are leap years. 145 // However, every hundredth year is not a leap year. 1900 and 2100 are not leap years. 146 // Every four hundred years, there's a leap year after all. 2000 and 2400 are leap years. 147 148 static const int leapDaysBefore1971By4Rule = 1970 / 4; 149 static const int excludedLeapDaysBefore1971By100Rule = 1970 / 100; 150 static const int leapDaysBefore1971By400Rule = 1970 / 400; 151 152 const double yearMinusOne = year - 1; 153 const double yearsToAddBy4Rule = floor(yearMinusOne / 4.0) - leapDaysBefore1971By4Rule; 154 const double yearsToExcludeBy100Rule = floor(yearMinusOne / 100.0) - excludedLeapDaysBefore1971By100Rule; 155 const double yearsToAddBy400Rule = floor(yearMinusOne / 400.0) - leapDaysBefore1971By400Rule; 156 157 return 365.0 * (year - 1970) + yearsToAddBy4Rule - yearsToExcludeBy100Rule + yearsToAddBy400Rule; 158 } 159 160 static double msToDays(double ms) 161 { 162 return floor(ms / msPerDay); 163 } 164 165 static void appendTwoDigitNumber(StringBuilder& builder, int number) 166 { 167 ASSERT(number >= 0 && number < 100); 168 if (number <= 9) 169 builder.append('0'); 170 builder.appendNumber(number); 171 } 172 173 int msToYear(double ms) 174 { 175 int approxYear = static_cast<int>(floor(ms / (msPerDay * 365.2425)) + 1970); 176 double msFromApproxYearTo1970 = msPerDay * daysFrom1970ToYear(approxYear); 177 if (msFromApproxYearTo1970 > ms) 178 return approxYear - 1; 179 if (msFromApproxYearTo1970 + msPerDay * daysInYear(approxYear) <= ms) 180 return approxYear + 1; 181 return approxYear; 182 } 183 184 int dayInYear(double ms, int year) 185 { 186 return static_cast<int>(msToDays(ms) - daysFrom1970ToYear(year)); 187 } 188 189 static inline double msToMilliseconds(double ms) 190 { 191 double result = fmod(ms, msPerDay); 192 if (result < 0) 193 result += msPerDay; 194 return result; 195 } 196 197 int monthFromDayInYear(int dayInYear, bool leapYear) 198 { 199 const int d = dayInYear; 200 int step; 201 202 if (d < (step = 31)) 203 return 0; 204 step += (leapYear ? 29 : 28); 205 if (d < step) 206 return 1; 207 if (d < (step += 31)) 208 return 2; 209 if (d < (step += 30)) 210 return 3; 211 if (d < (step += 31)) 212 return 4; 213 if (d < (step += 30)) 214 return 5; 215 if (d < (step += 31)) 216 return 6; 217 if (d < (step += 31)) 218 return 7; 219 if (d < (step += 30)) 220 return 8; 221 if (d < (step += 31)) 222 return 9; 223 if (d < (step += 30)) 224 return 10; 225 return 11; 226 } 227 228 static inline bool checkMonth(int dayInYear, int& startDayOfThisMonth, int& startDayOfNextMonth, int daysInThisMonth) 229 { 230 startDayOfThisMonth = startDayOfNextMonth; 231 startDayOfNextMonth += daysInThisMonth; 232 return (dayInYear <= startDayOfNextMonth); 233 } 234 235 int dayInMonthFromDayInYear(int dayInYear, bool leapYear) 236 { 237 const int d = dayInYear; 238 int step; 239 int next = 30; 240 241 if (d <= next) 242 return d + 1; 243 const int daysInFeb = (leapYear ? 29 : 28); 244 if (checkMonth(d, step, next, daysInFeb)) 245 return d - step; 246 if (checkMonth(d, step, next, 31)) 247 return d - step; 248 if (checkMonth(d, step, next, 30)) 249 return d - step; 250 if (checkMonth(d, step, next, 31)) 251 return d - step; 252 if (checkMonth(d, step, next, 30)) 253 return d - step; 254 if (checkMonth(d, step, next, 31)) 255 return d - step; 256 if (checkMonth(d, step, next, 31)) 257 return d - step; 258 if (checkMonth(d, step, next, 30)) 259 return d - step; 260 if (checkMonth(d, step, next, 31)) 261 return d - step; 262 if (checkMonth(d, step, next, 30)) 263 return d - step; 264 step = next; 265 return d - step; 266 } 267 268 int dayInYear(int year, int month, int day) 269 { 270 return firstDayOfMonth[isLeapYear(year)][month] + day - 1; 271 } 272 273 double dateToDaysFrom1970(int year, int month, int day) 274 { 275 year += month / 12; 276 277 month %= 12; 278 if (month < 0) { 279 month += 12; 280 --year; 281 } 282 283 double yearday = floor(daysFrom1970ToYear(year)); 284 ASSERT((year >= 1970 && yearday >= 0) || (year < 1970 && yearday < 0)); 285 return yearday + dayInYear(year, month, day); 286 } 287 288 // There is a hard limit at 2038 that we currently do not have a workaround 289 // for (rdar://problem/5052975). 290 static inline int maximumYearForDST() 291 { 292 return 2037; 293 } 294 295 static inline double jsCurrentTime() 296 { 297 // JavaScript doesn't recognize fractions of a millisecond. 298 return floor(WTF::currentTimeMS()); 299 } 300 301 static inline int minimumYearForDST() 302 { 303 // Because of the 2038 issue (see maximumYearForDST) if the current year is 304 // greater than the max year minus 27 (2010), we want to use the max year 305 // minus 27 instead, to ensure there is a range of 28 years that all years 306 // can map to. 307 return std::min(msToYear(jsCurrentTime()), maximumYearForDST() - 27) ; 308 } 309 310 /* 311 * Find an equivalent year for the one given, where equivalence is deterined by 312 * the two years having the same leapness and the first day of the year, falling 313 * on the same day of the week. 314 * 315 * This function returns a year between this current year and 2037, however this 316 * function will potentially return incorrect results if the current year is after 317 * 2010, (rdar://problem/5052975), if the year passed in is before 1900 or after 318 * 2100, (rdar://problem/5055038). 319 */ 320 static int equivalentYearForDST(int year) 321 { 322 // It is ok if the cached year is not the current year as long as the rules 323 // for DST did not change between the two years; if they did the app would need 324 // to be restarted. 325 static int minYear = minimumYearForDST(); 326 int maxYear = maximumYearForDST(); 327 328 int difference; 329 if (year > maxYear) 330 difference = minYear - year; 331 else if (year < minYear) 332 difference = maxYear - year; 333 else 334 return year; 335 336 int quotient = difference / 28; 337 int product = (quotient) * 28; 338 339 year += product; 340 ASSERT((year >= minYear && year <= maxYear) || (product - year == static_cast<int>(std::numeric_limits<double>::quiet_NaN()))); 341 return year; 342 } 343 344 static double calculateUTCOffset() 345 { 346 #if OS(WIN) 347 TIME_ZONE_INFORMATION timeZoneInformation; 348 GetTimeZoneInformation(&timeZoneInformation); 349 int32_t bias = timeZoneInformation.Bias + timeZoneInformation.StandardBias; 350 return -bias * 60 * 1000; 351 #else 352 time_t localTime = time(0); 353 tm localt; 354 getLocalTime(&localTime, &localt); 355 356 // tm_gmtoff includes any daylight savings offset, so subtract it. 357 return static_cast<double>(localt.tm_gmtoff * msPerSecond - (localt.tm_isdst > 0 ? msPerHour : 0)); 358 #endif 359 } 360 361 /* 362 * Get the DST offset for the time passed in. 363 */ 364 static double calculateDSTOffsetSimple(double localTimeSeconds, double utcOffset) 365 { 366 if (localTimeSeconds > maxUnixTime) 367 localTimeSeconds = maxUnixTime; 368 else if (localTimeSeconds < 0) // Go ahead a day to make localtime work (does not work with 0) 369 localTimeSeconds += secondsPerDay; 370 371 // FIXME: time_t has a potential problem in 2038 372 time_t localTime = static_cast<time_t>(localTimeSeconds); 373 374 tm localTM; 375 getLocalTime(&localTime, &localTM); 376 377 return localTM.tm_isdst > 0 ? msPerHour : 0; 378 } 379 380 // Get the DST offset, given a time in UTC 381 static double calculateDSTOffset(double ms, double utcOffset) 382 { 383 // On Mac OS X, the call to localtime (see calculateDSTOffsetSimple) will return historically accurate 384 // DST information (e.g. New Zealand did not have DST from 1946 to 1974) however the JavaScript 385 // standard explicitly dictates that historical information should not be considered when 386 // determining DST. For this reason we shift away from years that localtime can handle but would 387 // return historically accurate information. 388 int year = msToYear(ms); 389 int equivalentYear = equivalentYearForDST(year); 390 if (year != equivalentYear) { 391 bool leapYear = isLeapYear(year); 392 int dayInYearLocal = dayInYear(ms, year); 393 int dayInMonth = dayInMonthFromDayInYear(dayInYearLocal, leapYear); 394 int month = monthFromDayInYear(dayInYearLocal, leapYear); 395 double day = dateToDaysFrom1970(equivalentYear, month, dayInMonth); 396 ms = (day * msPerDay) + msToMilliseconds(ms); 397 } 398 399 return calculateDSTOffsetSimple(ms / msPerSecond, utcOffset); 400 } 401 402 void initializeDates() 403 { 404 #if ENABLE(ASSERT) 405 static bool alreadyInitialized; 406 ASSERT(!alreadyInitialized); 407 alreadyInitialized = true; 408 #endif 409 410 equivalentYearForDST(2000); // Need to call once to initialize a static used in this function. 411 } 412 413 static inline double ymdhmsToSeconds(int year, long mon, long day, long hour, long minute, double second) 414 { 415 double days = (day - 32075) 416 + floor(1461 * (year + 4800.0 + (mon - 14) / 12) / 4) 417 + 367 * (mon - 2 - (mon - 14) / 12 * 12) / 12 418 - floor(3 * ((year + 4900.0 + (mon - 14) / 12) / 100) / 4) 419 - 2440588; 420 return ((days * hoursPerDay + hour) * minutesPerHour + minute) * secondsPerMinute + second; 421 } 422 423 // We follow the recommendation of RFC 2822 to consider all 424 // obsolete time zones not listed here equivalent to "-0000". 425 static const struct KnownZone { 426 #if !OS(WIN) 427 const 428 #endif 429 char tzName[4]; 430 int tzOffset; 431 } known_zones[] = { 432 { "UT", 0 }, 433 { "GMT", 0 }, 434 { "EST", -300 }, 435 { "EDT", -240 }, 436 { "CST", -360 }, 437 { "CDT", -300 }, 438 { "MST", -420 }, 439 { "MDT", -360 }, 440 { "PST", -480 }, 441 { "PDT", -420 } 442 }; 443 444 inline static void skipSpacesAndComments(const char*& s) 445 { 446 int nesting = 0; 447 char ch; 448 while ((ch = *s)) { 449 if (!isASCIISpace(ch)) { 450 if (ch == '(') 451 nesting++; 452 else if (ch == ')' && nesting > 0) 453 nesting--; 454 else if (nesting == 0) 455 break; 456 } 457 s++; 458 } 459 } 460 461 // returns 0-11 (Jan-Dec); -1 on failure 462 static int findMonth(const char* monthStr) 463 { 464 ASSERT(monthStr); 465 char needle[4]; 466 for (int i = 0; i < 3; ++i) { 467 if (!*monthStr) 468 return -1; 469 needle[i] = static_cast<char>(toASCIILower(*monthStr++)); 470 } 471 needle[3] = '\0'; 472 const char *haystack = "janfebmaraprmayjunjulaugsepoctnovdec"; 473 const char *str = strstr(haystack, needle); 474 if (str) { 475 int position = static_cast<int>(str - haystack); 476 if (position % 3 == 0) 477 return position / 3; 478 } 479 return -1; 480 } 481 482 static bool parseInt(const char* string, char** stopPosition, int base, int* result) 483 { 484 long longResult = strtol(string, stopPosition, base); 485 // Avoid the use of errno as it is not available on Windows CE 486 if (string == *stopPosition || longResult <= std::numeric_limits<int>::min() || longResult >= std::numeric_limits<int>::max()) 487 return false; 488 *result = static_cast<int>(longResult); 489 return true; 490 } 491 492 static bool parseLong(const char* string, char** stopPosition, int base, long* result) 493 { 494 *result = strtol(string, stopPosition, base); 495 // Avoid the use of errno as it is not available on Windows CE 496 if (string == *stopPosition || *result == std::numeric_limits<long>::min() || *result == std::numeric_limits<long>::max()) 497 return false; 498 return true; 499 } 500 501 // Odd case where 'exec' is allowed to be 0, to accomodate a caller in WebCore. 502 static double parseDateFromNullTerminatedCharacters(const char* dateString, bool& haveTZ, int& offset) 503 { 504 haveTZ = false; 505 offset = 0; 506 507 // This parses a date in the form: 508 // Tuesday, 09-Nov-99 23:12:40 GMT 509 // or 510 // Sat, 01-Jan-2000 08:00:00 GMT 511 // or 512 // Sat, 01 Jan 2000 08:00:00 GMT 513 // or 514 // 01 Jan 99 22:00 +0100 (exceptions in rfc822/rfc2822) 515 // ### non RFC formats, added for Javascript: 516 // [Wednesday] January 09 1999 23:12:40 GMT 517 // [Wednesday] January 09 23:12:40 GMT 1999 518 // 519 // We ignore the weekday. 520 521 // Skip leading space 522 skipSpacesAndComments(dateString); 523 524 long month = -1; 525 const char *wordStart = dateString; 526 // Check contents of first words if not number 527 while (*dateString && !isASCIIDigit(*dateString)) { 528 if (isASCIISpace(*dateString) || *dateString == '(') { 529 if (dateString - wordStart >= 3) 530 month = findMonth(wordStart); 531 skipSpacesAndComments(dateString); 532 wordStart = dateString; 533 } else 534 dateString++; 535 } 536 537 // Missing delimiter between month and day (like "January29")? 538 if (month == -1 && wordStart != dateString) 539 month = findMonth(wordStart); 540 541 skipSpacesAndComments(dateString); 542 543 if (!*dateString) 544 return std::numeric_limits<double>::quiet_NaN(); 545 546 // ' 09-Nov-99 23:12:40 GMT' 547 char* newPosStr; 548 long day; 549 if (!parseLong(dateString, &newPosStr, 10, &day)) 550 return std::numeric_limits<double>::quiet_NaN(); 551 dateString = newPosStr; 552 553 if (!*dateString) 554 return std::numeric_limits<double>::quiet_NaN(); 555 556 if (day < 0) 557 return std::numeric_limits<double>::quiet_NaN(); 558 559 int year = 0; 560 if (day > 31) { 561 // ### where is the boundary and what happens below? 562 if (*dateString != '/') 563 return std::numeric_limits<double>::quiet_NaN(); 564 // looks like a YYYY/MM/DD date 565 if (!*++dateString) 566 return std::numeric_limits<double>::quiet_NaN(); 567 if (day <= std::numeric_limits<int>::min() || day >= std::numeric_limits<int>::max()) 568 return std::numeric_limits<double>::quiet_NaN(); 569 year = static_cast<int>(day); 570 if (!parseLong(dateString, &newPosStr, 10, &month)) 571 return std::numeric_limits<double>::quiet_NaN(); 572 month -= 1; 573 dateString = newPosStr; 574 if (*dateString++ != '/' || !*dateString) 575 return std::numeric_limits<double>::quiet_NaN(); 576 if (!parseLong(dateString, &newPosStr, 10, &day)) 577 return std::numeric_limits<double>::quiet_NaN(); 578 dateString = newPosStr; 579 } else if (*dateString == '/' && month == -1) { 580 dateString++; 581 // This looks like a MM/DD/YYYY date, not an RFC date. 582 month = day - 1; // 0-based 583 if (!parseLong(dateString, &newPosStr, 10, &day)) 584 return std::numeric_limits<double>::quiet_NaN(); 585 if (day < 1 || day > 31) 586 return std::numeric_limits<double>::quiet_NaN(); 587 dateString = newPosStr; 588 if (*dateString == '/') 589 dateString++; 590 if (!*dateString) 591 return std::numeric_limits<double>::quiet_NaN(); 592 } else { 593 if (*dateString == '-') 594 dateString++; 595 596 skipSpacesAndComments(dateString); 597 598 if (*dateString == ',') 599 dateString++; 600 601 if (month == -1) { // not found yet 602 month = findMonth(dateString); 603 if (month == -1) 604 return std::numeric_limits<double>::quiet_NaN(); 605 606 while (*dateString && *dateString != '-' && *dateString != ',' && !isASCIISpace(*dateString)) 607 dateString++; 608 609 if (!*dateString) 610 return std::numeric_limits<double>::quiet_NaN(); 611 612 // '-99 23:12:40 GMT' 613 if (*dateString != '-' && *dateString != '/' && *dateString != ',' && !isASCIISpace(*dateString)) 614 return std::numeric_limits<double>::quiet_NaN(); 615 dateString++; 616 } 617 } 618 619 if (month < 0 || month > 11) 620 return std::numeric_limits<double>::quiet_NaN(); 621 622 // '99 23:12:40 GMT' 623 if (year <= 0 && *dateString) { 624 if (!parseInt(dateString, &newPosStr, 10, &year)) 625 return std::numeric_limits<double>::quiet_NaN(); 626 } 627 628 // Don't fail if the time is missing. 629 long hour = 0; 630 long minute = 0; 631 long second = 0; 632 if (!*newPosStr) 633 dateString = newPosStr; 634 else { 635 // ' 23:12:40 GMT' 636 if (!(isASCIISpace(*newPosStr) || *newPosStr == ',')) { 637 if (*newPosStr != ':') 638 return std::numeric_limits<double>::quiet_NaN(); 639 // There was no year; the number was the hour. 640 year = -1; 641 } else { 642 // in the normal case (we parsed the year), advance to the next number 643 dateString = ++newPosStr; 644 skipSpacesAndComments(dateString); 645 } 646 647 parseLong(dateString, &newPosStr, 10, &hour); 648 // Do not check for errno here since we want to continue 649 // even if errno was set becasue we are still looking 650 // for the timezone! 651 652 // Read a number? If not, this might be a timezone name. 653 if (newPosStr != dateString) { 654 dateString = newPosStr; 655 656 if (hour < 0 || hour > 23) 657 return std::numeric_limits<double>::quiet_NaN(); 658 659 if (!*dateString) 660 return std::numeric_limits<double>::quiet_NaN(); 661 662 // ':12:40 GMT' 663 if (*dateString++ != ':') 664 return std::numeric_limits<double>::quiet_NaN(); 665 666 if (!parseLong(dateString, &newPosStr, 10, &minute)) 667 return std::numeric_limits<double>::quiet_NaN(); 668 dateString = newPosStr; 669 670 if (minute < 0 || minute > 59) 671 return std::numeric_limits<double>::quiet_NaN(); 672 673 // ':40 GMT' 674 if (*dateString && *dateString != ':' && !isASCIISpace(*dateString)) 675 return std::numeric_limits<double>::quiet_NaN(); 676 677 // seconds are optional in rfc822 + rfc2822 678 if (*dateString ==':') { 679 dateString++; 680 681 if (!parseLong(dateString, &newPosStr, 10, &second)) 682 return std::numeric_limits<double>::quiet_NaN(); 683 dateString = newPosStr; 684 685 if (second < 0 || second > 59) 686 return std::numeric_limits<double>::quiet_NaN(); 687 } 688 689 skipSpacesAndComments(dateString); 690 691 if (strncasecmp(dateString, "AM", 2) == 0) { 692 if (hour > 12) 693 return std::numeric_limits<double>::quiet_NaN(); 694 if (hour == 12) 695 hour = 0; 696 dateString += 2; 697 skipSpacesAndComments(dateString); 698 } else if (strncasecmp(dateString, "PM", 2) == 0) { 699 if (hour > 12) 700 return std::numeric_limits<double>::quiet_NaN(); 701 if (hour != 12) 702 hour += 12; 703 dateString += 2; 704 skipSpacesAndComments(dateString); 705 } 706 } 707 } 708 709 // The year may be after the time but before the time zone. 710 if (isASCIIDigit(*dateString) && year == -1) { 711 if (!parseInt(dateString, &newPosStr, 10, &year)) 712 return std::numeric_limits<double>::quiet_NaN(); 713 dateString = newPosStr; 714 skipSpacesAndComments(dateString); 715 } 716 717 // Don't fail if the time zone is missing. 718 // Some websites omit the time zone (4275206). 719 if (*dateString) { 720 if (strncasecmp(dateString, "GMT", 3) == 0 || strncasecmp(dateString, "UTC", 3) == 0) { 721 dateString += 3; 722 haveTZ = true; 723 } 724 725 if (*dateString == '+' || *dateString == '-') { 726 int o; 727 if (!parseInt(dateString, &newPosStr, 10, &o)) 728 return std::numeric_limits<double>::quiet_NaN(); 729 dateString = newPosStr; 730 731 if (o < -9959 || o > 9959) 732 return std::numeric_limits<double>::quiet_NaN(); 733 734 int sgn = (o < 0) ? -1 : 1; 735 o = abs(o); 736 if (*dateString != ':') { 737 if (o >= 24) 738 offset = ((o / 100) * 60 + (o % 100)) * sgn; 739 else 740 offset = o * 60 * sgn; 741 } else { // GMT+05:00 742 ++dateString; // skip the ':' 743 int o2; 744 if (!parseInt(dateString, &newPosStr, 10, &o2)) 745 return std::numeric_limits<double>::quiet_NaN(); 746 dateString = newPosStr; 747 offset = (o * 60 + o2) * sgn; 748 } 749 haveTZ = true; 750 } else { 751 for (size_t i = 0; i < WTF_ARRAY_LENGTH(known_zones); ++i) { 752 if (0 == strncasecmp(dateString, known_zones[i].tzName, strlen(known_zones[i].tzName))) { 753 offset = known_zones[i].tzOffset; 754 dateString += strlen(known_zones[i].tzName); 755 haveTZ = true; 756 break; 757 } 758 } 759 } 760 } 761 762 skipSpacesAndComments(dateString); 763 764 if (*dateString && year == -1) { 765 if (!parseInt(dateString, &newPosStr, 10, &year)) 766 return std::numeric_limits<double>::quiet_NaN(); 767 dateString = newPosStr; 768 skipSpacesAndComments(dateString); 769 } 770 771 // Trailing garbage 772 if (*dateString) 773 return std::numeric_limits<double>::quiet_NaN(); 774 775 // Y2K: Handle 2 digit years. 776 if (year >= 0 && year < 100) { 777 if (year < 50) 778 year += 2000; 779 else 780 year += 1900; 781 } 782 783 return ymdhmsToSeconds(year, month + 1, day, hour, minute, second) * msPerSecond; 784 } 785 786 double parseDateFromNullTerminatedCharacters(const char* dateString) 787 { 788 bool haveTZ; 789 int offset; 790 double ms = parseDateFromNullTerminatedCharacters(dateString, haveTZ, offset); 791 if (std::isnan(ms)) 792 return std::numeric_limits<double>::quiet_NaN(); 793 794 // fall back to local timezone 795 if (!haveTZ) { 796 double utcOffset = calculateUTCOffset(); 797 double dstOffset = calculateDSTOffset(ms, utcOffset); 798 offset = (utcOffset + dstOffset) / msPerMinute; 799 } 800 return ms - (offset * msPerMinute); 801 } 802 803 // See http://tools.ietf.org/html/rfc2822#section-3.3 for more information. 804 String makeRFC2822DateString(unsigned dayOfWeek, unsigned day, unsigned month, unsigned year, unsigned hours, unsigned minutes, unsigned seconds, int utcOffset) 805 { 806 StringBuilder stringBuilder; 807 stringBuilder.append(weekdayName[dayOfWeek]); 808 stringBuilder.appendLiteral(", "); 809 stringBuilder.appendNumber(day); 810 stringBuilder.append(' '); 811 stringBuilder.append(monthName[month]); 812 stringBuilder.append(' '); 813 stringBuilder.appendNumber(year); 814 stringBuilder.append(' '); 815 816 appendTwoDigitNumber(stringBuilder, hours); 817 stringBuilder.append(':'); 818 appendTwoDigitNumber(stringBuilder, minutes); 819 stringBuilder.append(':'); 820 appendTwoDigitNumber(stringBuilder, seconds); 821 stringBuilder.append(' '); 822 823 stringBuilder.append(utcOffset > 0 ? '+' : '-'); 824 int absoluteUTCOffset = abs(utcOffset); 825 appendTwoDigitNumber(stringBuilder, absoluteUTCOffset / 60); 826 appendTwoDigitNumber(stringBuilder, absoluteUTCOffset % 60); 827 828 return stringBuilder.toString(); 829 } 830 831 double convertToLocalTime(double ms) 832 { 833 double utcOffset = calculateUTCOffset(); 834 double dstOffset = calculateDSTOffset(ms, utcOffset); 835 return (ms + utcOffset + dstOffset); 836 } 837 838 } // namespace WTF 839
