CFDate.c

   1 /*
   2  * Copyright (c) 2014 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22  */
  23
  24 /*      CFDate.c
  25         Copyright (c) 1998-2013, Apple Inc. All rights reserved.
  26         Responsibility: Christopher Kane
  27 */
  28
  29 #include <CoreFoundation/CFDate.h>
  30 #include <CoreFoundation/CFTimeZone.h>
  31 #include <CoreFoundation/CFDictionary.h>
  32 #include <CoreFoundation/CFArray.h>
  33 #include <CoreFoundation/CFString.h>
  34 #include <CoreFoundation/CFNumber.h>
  35 #include "CFInternal.h"
  36 #include <math.h>
  37 #include <dispatch/dispatch.h>
  38
  39 #if DEPLOYMENT_TARGET_MACOSX || DEPLOYMENT_TARGET_EMBEDDED || DEPLOYMENT_TARGET_EMBEDDED_MINI || DEPLOYMENT_TARGET_LINUX
  40 #include <sys/time.h>
  41 #endif
  42
  43 #define DEFINE_CFDATE_FUNCTIONS 1
  44
  45 /* cjk: The Julian Date for the reference date is 2451910.5,
  46         I think, in case that's ever useful. */
  47
  48 #if DEFINE_CFDATE_FUNCTIONS
  49
  50 const CFTimeInterval kCFAbsoluteTimeIntervalSince1970 = 978307200.0L;
  51 const CFTimeInterval kCFAbsoluteTimeIntervalSince1904 = 3061152000.0L;
  52
  53 CF_PRIVATE double __CFTSRRate = 0.0;
  54 static double __CF1_TSRRate = 0.0;
  55
  56 CF_PRIVATE uint64_t __CFTimeIntervalToTSR(CFTimeInterval ti) {
  57     if ((ti * __CFTSRRate) > INT64_MAX / 2) return (INT64_MAX / 2);
  58     return (uint64_t)(ti * __CFTSRRate);
  59 }
  60
  61 CF_PRIVATE CFTimeInterval __CFTSRToTimeInterval(uint64_t tsr) {
  62     return (CFTimeInterval)((double)tsr * __CF1_TSRRate);
  63 }
  64
  65 CF_PRIVATE CFTimeInterval __CFTimeIntervalUntilTSR(uint64_t tsr) {
  66     CFDateGetTypeID();
  67     uint64_t now = mach_absolute_time();
  68     if (tsr >= now) {
  69         return __CFTSRToTimeInterval(tsr - now);
  70     } else {
  71         return -__CFTSRToTimeInterval(now - tsr);
  72     }
  73 }
  74
  75 // Technically this is 'TSR units' not a strict 'TSR' absolute time
  76 CF_PRIVATE uint64_t __CFTSRToNanoseconds(uint64_t tsr) {
  77     double tsrInNanoseconds = floor(tsr * __CF1_TSRRate * NSEC_PER_SEC);
  78     uint64_t ns = (uint64_t)tsrInNanoseconds;
  79     return ns;
  80 }
  81
  82 CF_PRIVATE dispatch_time_t __CFTSRToDispatchTime(uint64_t tsr) {
  83     uint64_t tsrInNanoseconds = __CFTSRToNanoseconds(tsr);
  84
  85     // It's important to clamp this value to INT64_MAX or it will become interpreted by dispatch_time as a relative value instead of absolute time
  86     if (tsrInNanoseconds > INT64_MAX - 1) tsrInNanoseconds = INT64_MAX - 1;
  87
  88     // 2nd argument of dispatch_time is a value in nanoseconds, but tsr does not equal nanoseconds on all platforms.
  89     return dispatch_time(1, (int64_t)tsrInNanoseconds);
  90 }
  91
  92 CFAbsoluteTime CFAbsoluteTimeGetCurrent(void) {
  93     CFAbsoluteTime ret;
  94     struct timeval tv;
  95     gettimeofday(&tv, NULL);
  96     ret = (CFTimeInterval)tv.tv_sec - kCFAbsoluteTimeIntervalSince1970;
  97     ret += (1.0E-6 * (CFTimeInterval)tv.tv_usec);
  98     return ret;
  99 }
 100
 101 CF_PRIVATE void __CFDateInitialize(void) {
 102 #if DEPLOYMENT_TARGET_MACOSX || DEPLOYMENT_TARGET_EMBEDDED || DEPLOYMENT_TARGET_EMBEDDED_MINI
 103     struct mach_timebase_info info;
 104     mach_timebase_info(&info);
 105     __CFTSRRate = (1.0E9 / (double)info.numer) * (double)info.denom;
 106     __CF1_TSRRate = 1.0 / __CFTSRRate;
 107 #elif DEPLOYMENT_TARGET_WINDOWS
 108     LARGE_INTEGER freq;
 109     if (!QueryPerformanceFrequency(&freq)) {
 110         HALT;
 111     }
 112     __CFTSRRate = (double)freq.QuadPart;
 113     __CF1_TSRRate = 1.0 / __CFTSRRate;
 114 #elif DEPLOYMENT_TARGET_LINUX
 115     struct timespec res;
 116     if (clock_getres(CLOCK_MONOTONIC, &res) != 0) {
 117         HALT;
 118     }
 119     __CFTSRRate = res.tv_sec + (1000000000 * res.tv_nsec);
 120     __CF1_TSRRate = 1.0 / __CFTSRRate;
 121 #else
 122 #error Unable to initialize date
 123 #endif
 124     CFDateGetTypeID(); // cause side-effects
 125 }
 126
 127 struct __CFDate {
 128     CFRuntimeBase _base;
 129     CFAbsoluteTime _time;       /* immutable */
 130 };
 131
 132 static Boolean __CFDateEqual(CFTypeRef cf1, CFTypeRef cf2) {
 133     CFDateRef date1 = (CFDateRef)cf1;
 134     CFDateRef date2 = (CFDateRef)cf2;
 135     if (date1->_time != date2->_time) return false;
 136     return true;
 137 }
 138
 139 static CFHashCode __CFDateHash(CFTypeRef cf) {
 140     CFDateRef date = (CFDateRef)cf;
 141     return (CFHashCode)(float)floor(date->_time);
 142 }
 143
 144 static CFStringRef __CFDateCopyDescription(CFTypeRef cf) {
 145     CFDateRef date = (CFDateRef)cf;
 146     return CFStringCreateWithFormat(CFGetAllocator(date), NULL, CFSTR("<CFDate %p [%p]>{time = %0.09g}"), cf, CFGetAllocator(date), date->_time);
 147 }
 148
 149 static CFTypeID __kCFDateTypeID = _kCFRuntimeNotATypeID;
 150
 151 static const CFRuntimeClass __CFDateClass = {
 152     0,
 153     "CFDate",
 154     NULL,       // init
 155     NULL,       // copy
 156     NULL,       // dealloc
 157     __CFDateEqual,
 158     __CFDateHash,
 159     NULL,       //
 160     __CFDateCopyDescription
 161 };
 162
 163 CFTypeID CFDateGetTypeID(void) {
 164     if (_kCFRuntimeNotATypeID == __kCFDateTypeID) __kCFDateTypeID = _CFRuntimeRegisterClass(&__CFDateClass);
 165     return __kCFDateTypeID;
 166 }
 167
 168 CFDateRef CFDateCreate(CFAllocatorRef allocator, CFAbsoluteTime at) {
 169     CFDateRef memory;
 170     uint32_t size;
 171     size = sizeof(struct __CFDate) - sizeof(CFRuntimeBase);
 172     memory = (CFDateRef)_CFRuntimeCreateInstance(allocator, CFDateGetTypeID(), size, NULL);
 173     if (NULL == memory) {
 174         return NULL;
 175     }
 176     ((struct __CFDate *)memory)->_time = at;
 177     return memory;
 178 }
 179
 180 CFTimeInterval CFDateGetAbsoluteTime(CFDateRef date) {
 181     CF_OBJC_FUNCDISPATCHV(CFDateGetTypeID(), CFTimeInterval, (NSDate *)date, timeIntervalSinceReferenceDate);
 182     __CFGenericValidateType(date, CFDateGetTypeID());
 183     return date->_time;
 184 }
 185
 186 CFTimeInterval CFDateGetTimeIntervalSinceDate(CFDateRef date, CFDateRef otherDate) {
 187     CF_OBJC_FUNCDISPATCHV(CFDateGetTypeID(), CFTimeInterval, (NSDate *)date, timeIntervalSinceDate:(NSDate *)otherDate);
 188     __CFGenericValidateType(date, CFDateGetTypeID());
 189     __CFGenericValidateType(otherDate, CFDateGetTypeID());
 190     return date->_time - otherDate->_time;
 191 }
 192
 193 CFComparisonResult CFDateCompare(CFDateRef date, CFDateRef otherDate, void *context) {
 194     CF_OBJC_FUNCDISPATCHV(CFDateGetTypeID(), CFComparisonResult, (NSDate *)date, compare:(NSDate *)otherDate);
 195     __CFGenericValidateType(date, CFDateGetTypeID());
 196     __CFGenericValidateType(otherDate, CFDateGetTypeID());
 197     if (date->_time < otherDate->_time) return kCFCompareLessThan;
 198     if (date->_time > otherDate->_time) return kCFCompareGreaterThan;
 199     return kCFCompareEqualTo;
 200 }
 201
 202 #endif
 203
 204 CF_INLINE int32_t __CFDoubleModToInt(double d, int32_t modulus) {
 205     int32_t result = (int32_t)(float)floor(d - floor(d / modulus) * modulus);
 206     if (result < 0) result += modulus;
 207     return result;
 208 }
 209
 210 CF_INLINE double __CFDoubleMod(double d, int32_t modulus) {
 211     double result = d - floor(d / modulus) * modulus;
 212     if (result < 0.0) result += (double)modulus;
 213     return result;
 214 }
 215
 216 static const uint8_t daysInMonth[16] = {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31, 0, 0, 0};
 217 static const uint16_t daysBeforeMonth[16] = {0, 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365, 0, 0};
 218 static const uint16_t daysAfterMonth[16] = {365, 334, 306, 275, 245, 214, 184, 153, 122, 92, 61, 31, 0, 0, 0, 0};
 219
 220 CF_INLINE bool isleap(int64_t year) {
 221     int64_t y = (year + 1) % 400;       /* correct to nearest multiple-of-400 year, then find the remainder */
 222     if (y < 0) y = -y;
 223     return (0 == (y & 3) && 100 != y && 200 != y && 300 != y);
 224 }
 225
 226 /* year arg is absolute year; Gregorian 2001 == year 0; 2001/1/1 = absolute date 0 */
 227 CF_INLINE uint8_t __CFDaysInMonth(int8_t month, int64_t year, bool leap) {
 228     return daysInMonth[month] + (2 == month && leap);
 229 }
 230
 231 /* year arg is absolute year; Gregorian 2001 == year 0; 2001/1/1 = absolute date 0 */
 232 CF_INLINE uint16_t __CFDaysBeforeMonth(int8_t month, int64_t year, bool leap) {
 233     return daysBeforeMonth[month] + (2 < month && leap);
 234 }
 235
 236 /* year arg is absolute year; Gregorian 2001 == year 0; 2001/1/1 = absolute date 0 */
 237 CF_INLINE uint16_t __CFDaysAfterMonth(int8_t month, int64_t year, bool leap) {
 238     return daysAfterMonth[month] + (month < 2 && leap);
 239 }
 240
 241 /* year arg is absolute year; Gregorian 2001 == year 0; 2001/1/1 = absolute date 0 */
 242 static void __CFYMDFromAbsolute(int64_t absolute, int64_t *year, int8_t *month, int8_t *day) {
 243     int64_t b = absolute / 146097; // take care of as many multiples of 400 years as possible
 244     int64_t y = b * 400;
 245     uint16_t ydays;
 246     absolute -= b * 146097;
 247     while (absolute < 0) {
 248         y -= 1;
 249         absolute += __CFDaysAfterMonth(0, y, isleap(y));
 250     }
 251     /* Now absolute is non-negative days to add to year */
 252     ydays = __CFDaysAfterMonth(0, y, isleap(y));
 253     while (ydays <= absolute) {
 254         y += 1;
 255         absolute -= ydays;
 256         ydays = __CFDaysAfterMonth(0, y, isleap(y));
 257     }
 258     /* Now we have year and days-into-year */
 259     if (year) *year = y;
 260     if (month || day) {
 261         int8_t m = absolute / 33 + 1; /* search from the approximation */
 262         bool leap = isleap(y);
 263         while (__CFDaysBeforeMonth(m + 1, y, leap) <= absolute) m++;
 264         if (month) *month = m;
 265         if (day) *day = absolute - __CFDaysBeforeMonth(m, y, leap) + 1;
 266     }
 267 }
 268
 269 /* year arg is absolute year; Gregorian 2001 == year 0; 2001/1/1 = absolute date 0 */
 270 static double __CFAbsoluteFromYMD(int64_t year, int8_t month, int8_t day) {
 271     double absolute = 0.0;
 272     int64_t idx;
 273     int64_t b = year / 400; // take care of as many multiples of 400 years as possible
 274     absolute += b * 146097.0;
 275     year -= b * 400;
 276     if (year < 0) {
 277         for (idx = year; idx < 0; idx++)
 278             absolute -= __CFDaysAfterMonth(0, idx, isleap(idx));
 279     } else {
 280         for (idx = 0; idx < year; idx++)
 281             absolute += __CFDaysAfterMonth(0, idx, isleap(idx));
 282     }
 283     /* Now add the days into the original year */
 284     absolute += __CFDaysBeforeMonth(month, year, isleap(year)) + day - 1;
 285     return absolute;
 286 }
 287
 288 Boolean CFGregorianDateIsValid(CFGregorianDate gdate, CFOptionFlags unitFlags) {
 289     if ((unitFlags & kCFGregorianUnitsYears) && (gdate.year <= 0)) return false;
 290     if ((unitFlags & kCFGregorianUnitsMonths) && (gdate.month < 1 || 12 < gdate.month)) return false;
 291     if ((unitFlags & kCFGregorianUnitsDays) && (gdate.day < 1 || 31 < gdate.day)) return false;
 292     if ((unitFlags & kCFGregorianUnitsHours) && (gdate.hour < 0 || 23 < gdate.hour)) return false;
 293     if ((unitFlags & kCFGregorianUnitsMinutes) && (gdate.minute < 0 || 59 < gdate.minute)) return false;
 294     if ((unitFlags & kCFGregorianUnitsSeconds) && (gdate.second < 0.0 || 60.0 <= gdate.second)) return false;
 295     if ((unitFlags & kCFGregorianUnitsDays) && (unitFlags & kCFGregorianUnitsMonths) && (unitFlags & kCFGregorianUnitsYears) && (__CFDaysInMonth(gdate.month, gdate.year - 2001, isleap(gdate.year - 2001)) < gdate.day)) return false;
 296     return true;
 297 }
 298
 299 CFAbsoluteTime CFGregorianDateGetAbsoluteTime(CFGregorianDate gdate, CFTimeZoneRef tz) {
 300     CFAbsoluteTime at;
 301     at = 86400.0 * __CFAbsoluteFromYMD(gdate.year - 2001, gdate.month, gdate.day);
 302     at += 3600.0 * gdate.hour + 60.0 * gdate.minute + gdate.second;
 303 #if DEPLOYMENT_TARGET_MACOSX || DEPLOYMENT_TARGET_EMBEDDED || DEPLOYMENT_TARGET_WINDOWS || DEPLOYMENT_TARGET_LINUX
 304     if (NULL != tz) {
 305         __CFGenericValidateType(tz, CFTimeZoneGetTypeID());
 306     }
 307     CFTimeInterval offset0, offset1;
 308     if (NULL != tz) {
 309         offset0 = CFTimeZoneGetSecondsFromGMT(tz, at);
 310         offset1 = CFTimeZoneGetSecondsFromGMT(tz, at - offset0);
 311         at -= offset1;
 312     }
 313 #endif
 314     return at;
 315 }
 316
 317 CFGregorianDate CFAbsoluteTimeGetGregorianDate(CFAbsoluteTime at, CFTimeZoneRef tz) {
 318     CFGregorianDate gdate;
 319     int64_t absolute, year;
 320     int8_t month, day;
 321     CFAbsoluteTime fixedat;
 322 #if DEPLOYMENT_TARGET_MACOSX || DEPLOYMENT_TARGET_EMBEDDED || DEPLOYMENT_TARGET_WINDOWS || DEPLOYMENT_TARGET_LINUX
 323     if (NULL != tz) {
 324         __CFGenericValidateType(tz, CFTimeZoneGetTypeID());
 325     }
 326     fixedat = at + (NULL != tz ? CFTimeZoneGetSecondsFromGMT(tz, at) : 0.0);
 327 #else
 328     fixedat = at;
 329 #endif
 330     absolute = (int64_t)floor(fixedat / 86400.0);
 331     __CFYMDFromAbsolute(absolute, &year, &month, &day);
 332     if (INT32_MAX - 2001 < year) year = INT32_MAX - 2001;
 333     gdate.year = year + 2001;
 334     gdate.month = month;
 335     gdate.day = day;
 336     gdate.hour = __CFDoubleModToInt(floor(fixedat / 3600.0), 24);
 337     gdate.minute = __CFDoubleModToInt(floor(fixedat / 60.0), 60);
 338     gdate.second = __CFDoubleMod(fixedat, 60);
 339     if (0.0 == gdate.second) gdate.second = 0.0;        // stomp out possible -0.0
 340     return gdate;
 341 }
 342
 343 /* Note that the units of years and months are not equal length, but are treated as such. */
 344 CFAbsoluteTime CFAbsoluteTimeAddGregorianUnits(CFAbsoluteTime at, CFTimeZoneRef tz, CFGregorianUnits units) {
 345     CFGregorianDate gdate;
 346     CFGregorianUnits working;
 347     CFAbsoluteTime candidate_at0, candidate_at1;
 348     uint8_t monthdays;
 349
 350 #if DEPLOYMENT_TARGET_MACOSX || DEPLOYMENT_TARGET_EMBEDDED || DEPLOYMENT_TARGET_WINDOWS || DEPLOYMENT_TARGET_LINUX
 351     if (NULL != tz) {
 352         __CFGenericValidateType(tz, CFTimeZoneGetTypeID());
 353     }
 354 #endif
 355
 356     /* Most people seem to expect years, then months, then days, etc.
 357         to be added in that order.  Thus, 27 April + (4 days, 1 month)
 358         = 31 May, and not 1 June. This is also relatively predictable.
 359
 360         On another issue, months not being equal length, people also
 361         seem to expect late day-of-month clamping (don't clamp as you
 362         go through months), but clamp before adding in the days. Late
 363         clamping is also more predictable given random starting points
 364         and random numbers of months added (ie Jan 31 + 2 months could
 365         be March 28 or March 29 in different years with aggressive
 366         clamping). Proportionality (28 Feb + 1 month = 31 March) is
 367         also not expected.
 368
 369         Also, people don't expect time zone transitions to have any
 370         effect when adding years and/or months and/or days, only.
 371         Hours, minutes, and seconds, though, are added in as humans
 372         would experience the passing of that time. What this means
 373         is that if the date, after adding years, months, and days
 374         lands on some date, and then adding hours, minutes, and
 375         seconds crosses a time zone transition, the time zone
 376         transition is accounted for. If adding years, months, and
 377         days gets the date into a different time zone offset period,
 378         that transition is not taken into account.
 379     */
 380     gdate = CFAbsoluteTimeGetGregorianDate(at, tz);
 381     /* We must work in a CFGregorianUnits, because the fields in the CFGregorianDate can easily overflow */
 382     working.years = gdate.year;
 383     working.months = gdate.month;
 384     working.days = gdate.day;
 385     working.years += units.years;
 386     working.months += units.months;
 387     while (12 < working.months) {
 388         working.months -= 12;
 389         working.years += 1;
 390     }
 391     while (working.months < 1) {
 392         working.months += 12;
 393         working.years -= 1;
 394     }
 395     monthdays = __CFDaysInMonth(working.months, working.years - 2001, isleap(working.years - 2001));
 396     if (monthdays < working.days) {     /* Clamp day to new month */
 397         working.days = monthdays;
 398     }
 399     working.days += units.days;
 400     while (monthdays < working.days) {
 401         working.months += 1;
 402         if (12 < working.months) {
 403             working.months -= 12;
 404             working.years += 1;
 405         }
 406         working.days -= monthdays;
 407         monthdays = __CFDaysInMonth(working.months, working.years - 2001, isleap(working.years - 2001));
 408     }
 409     while (working.days < 1) {
 410         working.months -= 1;
 411         if (working.months < 1) {
 412             working.months += 12;
 413             working.years -= 1;
 414         }
 415         monthdays = __CFDaysInMonth(working.months, working.years - 2001, isleap(working.years - 2001));
 416         working.days += monthdays;
 417     }
 418     gdate.year = working.years;
 419     gdate.month = working.months;
 420     gdate.day = working.days;
 421     /* Roll in hours, minutes, and seconds */
 422     candidate_at0 = CFGregorianDateGetAbsoluteTime(gdate, tz);
 423     candidate_at1 = candidate_at0 + 3600.0 * units.hours + 60.0 * units.minutes + units.seconds;
 424     /* If summing in the hours, minutes, and seconds delta pushes us
 425      * into a new time zone offset, that will automatically be taken
 426      * care of by the fact that we just add the raw time above. To
 427      * undo that effect, we'd have to get the time zone offsets for
 428      * candidate_at0 and candidate_at1 here, and subtract the
 429      * difference (offset1 - offset0) from candidate_at1. */
 430     return candidate_at1;
 431 }
 432
 433 /* at1 - at2.  The only constraint here is that this needs to be the inverse
 434 of CFAbsoluteTimeByAddingGregorianUnits(), but that's a very rigid constraint.
 435 Unfortunately, due to the nonuniformity of the year and month units, this
 436 inversion essentially has to approximate until it finds the answer. */
 437 CFGregorianUnits CFAbsoluteTimeGetDifferenceAsGregorianUnits(CFAbsoluteTime at1, CFAbsoluteTime at2, CFTimeZoneRef tz, CFOptionFlags unitFlags) {
 438     const int32_t seconds[5] = {366 * 24 * 3600, 31 * 24 * 3600, 24 * 3600, 3600, 60};
 439     CFGregorianUnits units = {0, 0, 0, 0, 0, 0.0};
 440     CFAbsoluteTime atold, atnew = at2;
 441     int32_t idx, incr;
 442     incr = (at2 < at1) ? 1 : -1;
 443     /* Successive approximation: years, then months, then days, then hours, then minutes. */
 444     for (idx = 0; idx < 5; idx++) {
 445         if (unitFlags & (1 << idx)) {
 446             ((int32_t *)&units)[idx] = -3 * incr + (int32_t)((at1 - atnew) / seconds[idx]);
 447             do {
 448                 atold = atnew;
 449                 ((int32_t *)&units)[idx] += incr;
 450                 atnew = CFAbsoluteTimeAddGregorianUnits(at2, tz, units);
 451             } while ((1 == incr && atnew <= at1) || (-1 == incr && at1 <= atnew));
 452             ((int32_t *)&units)[idx] -= incr;
 453             atnew = atold;
 454         }
 455     }
 456     if (unitFlags & kCFGregorianUnitsSeconds) {
 457         units.seconds = at1 - atnew;
 458     }
 459     if (0.0 == units.seconds) units.seconds = 0.0;      // stomp out possible -0.0
 460     return units;
 461 }
 462
 463 SInt32 CFAbsoluteTimeGetDayOfWeek(CFAbsoluteTime at, CFTimeZoneRef tz) {
 464     int64_t absolute;
 465     CFAbsoluteTime fixedat;
 466 #if DEPLOYMENT_TARGET_MACOSX || DEPLOYMENT_TARGET_EMBEDDED || DEPLOYMENT_TARGET_WINDOWS || DEPLOYMENT_TARGET_LINUX
 467     if (NULL != tz) {
 468         __CFGenericValidateType(tz, CFTimeZoneGetTypeID());
 469     }
 470     fixedat = at + (NULL != tz ? CFTimeZoneGetSecondsFromGMT(tz, at) : 0.0);
 471 #else
 472     fixedat = at;
 473 #endif
 474     absolute = (int64_t)floor(fixedat / 86400.0);
 475     return (absolute < 0) ? ((absolute + 1) % 7 + 7) : (absolute % 7 + 1); /* Monday = 1, etc. */
 476 }
 477
 478 SInt32 CFAbsoluteTimeGetDayOfYear(CFAbsoluteTime at, CFTimeZoneRef tz) {
 479     CFAbsoluteTime fixedat;
 480     int64_t absolute, year;
 481     int8_t month, day;
 482 #if DEPLOYMENT_TARGET_MACOSX || DEPLOYMENT_TARGET_EMBEDDED || DEPLOYMENT_TARGET_WINDOWS || DEPLOYMENT_TARGET_LINUX
 483     if (NULL != tz) {
 484         __CFGenericValidateType(tz, CFTimeZoneGetTypeID());
 485     }
 486     fixedat = at + (NULL != tz ? CFTimeZoneGetSecondsFromGMT(tz, at) : 0.0);
 487 #else
 488     fixedat = at;
 489 #endif
 490     absolute = (int64_t)floor(fixedat / 86400.0);
 491     __CFYMDFromAbsolute(absolute, &year, &month, &day);
 492     return __CFDaysBeforeMonth(month, year, isleap(year)) + day;
 493 }
 494
 495 /* "the first week of a year is the one which includes the first Thursday" (ISO 8601) */
 496 SInt32 CFAbsoluteTimeGetWeekOfYear(CFAbsoluteTime at, CFTimeZoneRef tz) {
 497     int64_t absolute, year;
 498     int8_t month, day;
 499     CFAbsoluteTime fixedat;
 500 #if DEPLOYMENT_TARGET_MACOSX || DEPLOYMENT_TARGET_EMBEDDED || DEPLOYMENT_TARGET_WINDOWS || DEPLOYMENT_TARGET_LINUX
 501     if (NULL != tz) {
 502         __CFGenericValidateType(tz, CFTimeZoneGetTypeID());
 503     }
 504     fixedat = at + (NULL != tz ? CFTimeZoneGetSecondsFromGMT(tz, at) : 0.0);
 505 #else
 506     fixedat = at;
 507 #endif
 508     absolute = (int64_t)floor(fixedat / 86400.0);
 509     __CFYMDFromAbsolute(absolute, &year, &month, &day);
 510     double absolute0101 = __CFAbsoluteFromYMD(year, 1, 1);
 511     int64_t dow0101 = __CFDoubleModToInt(absolute0101, 7) + 1;
 512     /* First three and last three days of a year can end up in a week of a different year */
 513     if (1 == month && day < 4) {
 514         if ((day < 4 && 5 == dow0101) || (day < 3 && 6 == dow0101) || (day < 2 && 7 == dow0101)) {
 515             return 53;
 516         }
 517     }
 518     if (12 == month && 28 < day) {
 519         double absolute20101 = __CFAbsoluteFromYMD(year + 1, 1, 1);
 520         int64_t dow20101 = __CFDoubleModToInt(absolute20101, 7) + 1;
 521         if ((28 < day && 4 == dow20101) || (29 < day && 3 == dow20101) || (30 < day && 2 == dow20101)) {
 522             return 1;
 523         }
 524     }
 525     /* Days into year, plus a week-shifting correction, divided by 7. First week is 1. */
 526     return (__CFDaysBeforeMonth(month, year, isleap(year)) + day + (dow0101 - 11) % 7 + 2) / 7 + 1;
 527 }
 528
 529