dlls/ntdll/time.c

   1 /*
   2  * Conversion between Time and TimeFields
   3  *
   4  * RtlTimeToTimeFields, RtlTimeFieldsToTime and defines are taken from ReactOS and
   5  * adapted to wine with special permissions of the author
   6  * Rex Jolliff (rex@lvcablemodem.com)
   7  *
   8  *
   9  */
  10
  11 #include <string.h>
  12 #include "ntddk.h"
  13 #include "debugtools.h"
  14 #include "file.h"
  15
  16 DEFAULT_DEBUG_CHANNEL(ntdll)
  17
  18 #define TICKSPERSEC        10000000
  19 #define TICKSPERMSEC       10000
  20 #define SECSPERDAY         86400
  21 #define SECSPERHOUR        3600
  22 #define SECSPERMIN         60
  23 #define MINSPERHOUR        60
  24 #define HOURSPERDAY        24
  25 #define EPOCHWEEKDAY       0
  26 #define DAYSPERWEEK        7
  27 #define EPOCHYEAR          1601
  28 #define DAYSPERNORMALYEAR  365
  29 #define DAYSPERLEAPYEAR    366
  30 #define MONSPERYEAR        12
  31
  32 static const int YearLengths[2] = {DAYSPERNORMALYEAR, DAYSPERLEAPYEAR};
  33 static const int MonthLengths[2][MONSPERYEAR] =
  34 {
  35         { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 },
  36         { 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }
  37 };
  38
  39 static inline int IsLeapYear(int Year)
  40 {
  41         return Year % 4 == 0 && (Year % 100 != 0 || Year % 400 == 0) ? 1 : 0;
  42 }
  43
  44 static inline void NormalizeTimeFields(CSHORT *FieldToNormalize, CSHORT *CarryField,int Modulus)
  45 {
  46         *FieldToNormalize = (CSHORT) (*FieldToNormalize - Modulus);
  47         *CarryField = (CSHORT) (*CarryField + 1);
  48 }
  49
  50 /******************************************************************************
  51  *  RtlTimeToTimeFields         [NTDLL.265]
  52  *
  53  */
  54
  55 VOID WINAPI RtlTimeToTimeFields(
  56         PLARGE_INTEGER liTime,
  57         PTIME_FIELDS TimeFields)
  58 {
  59         const int *Months;
  60         int LeapSecondCorrections, SecondsInDay, CurYear;
  61         int LeapYear, CurMonth, GMTOffset;
  62         long int Days;
  63         long long int Time = *(long long int *)&liTime;
  64
  65         /* Extract millisecond from time and convert time into seconds */
  66         TimeFields->Milliseconds = (CSHORT) ((Time % TICKSPERSEC) / TICKSPERMSEC);
  67         Time = Time / TICKSPERSEC;
  68
  69         /* FIXME: Compute the number of leap second corrections here */
  70         LeapSecondCorrections = 0;
  71
  72         /* FIXME: get the GMT offset here */
  73         GMTOffset = 0;
  74
  75         /* Split the time into days and seconds within the day */
  76         Days = Time / SECSPERDAY;
  77         SecondsInDay = Time % SECSPERDAY;
  78
  79         /* Adjust the values for GMT and leap seconds */
  80         SecondsInDay += (GMTOffset - LeapSecondCorrections);
  81         while (SecondsInDay < 0)
  82         { SecondsInDay += SECSPERDAY;
  83           Days--;
  84         }
  85         while (SecondsInDay >= SECSPERDAY)
  86         { SecondsInDay -= SECSPERDAY;
  87           Days++;
  88         }
  89
  90         /* compute time of day */
  91         TimeFields->Hour = (CSHORT) (SecondsInDay / SECSPERHOUR);
  92         SecondsInDay = SecondsInDay % SECSPERHOUR;
  93         TimeFields->Minute = (CSHORT) (SecondsInDay / SECSPERMIN);
  94         TimeFields->Second = (CSHORT) (SecondsInDay % SECSPERMIN);
  95
  96         /* FIXME: handle the possibility that we are on a leap second (i.e. Second = 60) */
  97
  98         /* compute day of week */
  99         TimeFields->Weekday = (CSHORT) ((EPOCHWEEKDAY + Days) % DAYSPERWEEK);
 100
 101         /* compute year */
 102         CurYear = EPOCHYEAR;
 103         /* FIXME: handle calendar modifications */
 104         while (1)
 105         { LeapYear = IsLeapYear(CurYear);
 106           if (Days < (long) YearLengths[LeapYear])
 107           { break;
 108           }
 109           CurYear++;
 110           Days = Days - (long) YearLengths[LeapYear];
 111         }
 112         TimeFields->Year = (CSHORT) CurYear;
 113
 114         /* Compute month of year */
 115         Months = MonthLengths[LeapYear];
 116         for (CurMonth = 0; Days >= (long) Months[CurMonth]; CurMonth++)
 117           Days = Days - (long) Months[CurMonth];
 118         TimeFields->Month = (CSHORT) (CurMonth + 1);
 119         TimeFields->Day = (CSHORT) (Days + 1);
 120 }
 121 /******************************************************************************
 122  *  RtlTimeFieldsToTime         [NTDLL.265]
 123  *
 124  */
 125 BOOLEAN WINAPI RtlTimeFieldsToTime(
 126         PTIME_FIELDS tfTimeFields,
 127         PLARGE_INTEGER Time)
 128 {
 129         int CurYear, CurMonth;
 130         long long int rcTime;
 131         TIME_FIELDS TimeFields = *tfTimeFields;
 132
 133         rcTime = 0;
 134
 135         /* FIXME: normalize the TIME_FIELDS structure here */
 136         while (TimeFields.Second >= SECSPERMIN)
 137         { NormalizeTimeFields(&TimeFields.Second, &TimeFields.Minute, SECSPERMIN);
 138         }
 139         while (TimeFields.Minute >= MINSPERHOUR)
 140         { NormalizeTimeFields(&TimeFields.Minute, &TimeFields.Hour, MINSPERHOUR);
 141         }
 142         while (TimeFields.Hour >= HOURSPERDAY)
 143         { NormalizeTimeFields(&TimeFields.Hour, &TimeFields.Day, HOURSPERDAY);
 144         }
 145         while (TimeFields.Day > MonthLengths[IsLeapYear(TimeFields.Year)][TimeFields.Month - 1])
 146         { NormalizeTimeFields(&TimeFields.Day, &TimeFields.Month, SECSPERMIN);
 147         }
 148         while (TimeFields.Month > MONSPERYEAR)
 149         { NormalizeTimeFields(&TimeFields.Month, &TimeFields.Year, MONSPERYEAR);
 150         }
 151
 152         /* FIXME: handle calendar corrections here */
 153         for (CurYear = EPOCHYEAR; CurYear < TimeFields.Year; CurYear++)
 154         { rcTime += YearLengths[IsLeapYear(CurYear)];
 155         }
 156         for (CurMonth = 1; CurMonth < TimeFields.Month; CurMonth++)
 157         { rcTime += MonthLengths[IsLeapYear(CurYear)][CurMonth - 1];
 158         }
 159         rcTime += TimeFields.Day - 1;
 160         rcTime *= SECSPERDAY;
 161         rcTime += TimeFields.Hour * SECSPERHOUR + TimeFields.Minute * SECSPERMIN + TimeFields.Second;
 162         rcTime *= TICKSPERSEC;
 163         rcTime += TimeFields.Milliseconds * TICKSPERMSEC;
 164         *Time = *(LARGE_INTEGER *)&rcTime;
 165
 166         return TRUE;
 167 }
 168 /************* end of code by Rex Jolliff (rex@lvcablemodem.com) *******************/
 169
 170 /******************************************************************************
 171  *  RtlSystemTimeToLocalTime    [NTDLL]
 172  */
 173 VOID WINAPI RtlSystemTimeToLocalTime(
 174         IN  PLARGE_INTEGER SystemTime,
 175         OUT PLARGE_INTEGER LocalTime)
 176 {
 177         FIXME("(%p, %p),stub!\n",SystemTime,LocalTime);
 178
 179         memcpy (LocalTime, SystemTime, sizeof (PLARGE_INTEGER));
 180 }
 181 /******************************************************************************
 182  *  RtlTimeToSecondsSince1980           [NTDLL]
 183  */
 184 BOOLEAN WINAPI RtlTimeToSecondsSince1980(
 185         LPFILETIME ft,
 186         LPDWORD timeret)
 187 {
 188         /* 1980 = 1970+10*365 days +  29. februar 1972 + 29.februar 1976 */
 189         *timeret = DOSFS_FileTimeToUnixTime(ft,NULL) - (10*365+2)*24*3600;
 190         return 1;
 191 }
 192
 193 /******************************************************************************
 194  *  RtlTimeToSecondsSince1970           [NTDLL]
 195  */
 196 BOOLEAN WINAPI RtlTimeToSecondsSince1970(
 197         LPFILETIME ft,
 198         LPDWORD timeret)
 199 {
 200         *timeret = DOSFS_FileTimeToUnixTime(ft,NULL);
 201         return 1;
 202 }
 203
 204 /******************************************************************************
 205  * RtlTimeToElapsedTimeFields [NTDLL.502]
 206  * FIXME: prototype guessed
 207  */
 208 VOID WINAPI RtlTimeToElapsedTimeFields(
 209         PLARGE_INTEGER liTime,
 210         PTIME_FIELDS TimeFields)
 211 {
 212         FIXME("(%p,%p): stub\n",liTime,TimeFields);
 213 }