reactos/ntoskrnl/ex/time.c

   1 /* $Id$
   2  *
   3  * COPYRIGHT:       See COPYING in the top level directory
   4  * PROJECT:         ReactOS kernel
   5  * FILE:            ntoskrnl/ex/time.c
   6  * PURPOSE:         Time
   7  *
   8  * PROGRAMMERS:     David Welch (welch@mcmail.com)
   9  */
  10
  11 /* INCLUDES *****************************************************************/
  12
  13 #include <ntoskrnl.h>
  14 #define NDEBUG
  15 #include <internal/debug.h>
  16
  17
  18 #define TICKSPERMINUTE  600000000
  19
  20 /* GLOBALS ******************************************************************/
  21
  22 /* Note: Bias[minutes] = UTC - local time */
  23 TIME_ZONE_INFORMATION ExpTimeZoneInfo;
  24 LARGE_INTEGER ExpTimeZoneBias;
  25 ULONG ExpTimeZoneId;
  26
  27
  28 /* FUNCTIONS ****************************************************************/
  29
  30 VOID
  31 INIT_FUNCTION
  32 STDCALL
  33 ExpInitTimeZoneInfo(VOID)
  34 {
  35   LARGE_INTEGER CurrentTime;
  36   NTSTATUS Status;
  37
  38   /* Read time zone information from the registry */
  39   Status = RtlQueryTimeZoneInformation(&ExpTimeZoneInfo);
  40   if (!NT_SUCCESS(Status))
  41     {
  42       memset(&ExpTimeZoneInfo, 0, sizeof(TIME_ZONE_INFORMATION));
  43
  44       ExpTimeZoneBias.QuadPart = (LONGLONG)0;
  45       ExpTimeZoneId = TIME_ZONE_ID_UNKNOWN;
  46     }
  47   else
  48     {
  49       /* FIXME: Calculate transition dates */
  50
  51       ExpTimeZoneBias.QuadPart =
  52         ((LONGLONG)(ExpTimeZoneInfo.Bias + ExpTimeZoneInfo.StandardBias)) * TICKSPERMINUTE;
  53       ExpTimeZoneId = TIME_ZONE_ID_STANDARD;
  54     }
  55
  56   SharedUserData->TimeZoneBias.High1Time = ExpTimeZoneBias.u.HighPart;
  57   SharedUserData->TimeZoneBias.High2Time = ExpTimeZoneBias.u.HighPart;
  58   SharedUserData->TimeZoneBias.LowPart = ExpTimeZoneBias.u.LowPart;
  59   SharedUserData->TimeZoneId = ExpTimeZoneId;
  60
  61   /* Convert boot time from local time to UTC */
  62   SystemBootTime.QuadPart += ExpTimeZoneBias.QuadPart;
  63
  64   /* Convert sytem time from local time to UTC */
  65   do
  66     {
  67       CurrentTime.u.HighPart = SharedUserData->SystemTime.High1Time;
  68       CurrentTime.u.LowPart = SharedUserData->SystemTime.LowPart;
  69     }
  70   while (CurrentTime.u.HighPart != SharedUserData->SystemTime.High2Time);
  71
  72   CurrentTime.QuadPart += ExpTimeZoneBias.QuadPart;
  73
  74   SharedUserData->SystemTime.LowPart = CurrentTime.u.LowPart;
  75   SharedUserData->SystemTime.High1Time = CurrentTime.u.HighPart;
  76   SharedUserData->SystemTime.High2Time = CurrentTime.u.HighPart;
  77 }
  78
  79
  80 NTSTATUS
  81 ExpSetTimeZoneInformation(PTIME_ZONE_INFORMATION TimeZoneInformation)
  82 {
  83   LARGE_INTEGER LocalTime;
  84   LARGE_INTEGER SystemTime;
  85   TIME_FIELDS TimeFields;
  86
  87   DPRINT("ExpSetTimeZoneInformation() called\n");
  88
  89   DPRINT("Old time zone bias: %d minutes\n",
  90          ExpTimeZoneInfo.Bias);
  91   DPRINT("Old time zone standard bias: %d minutes\n",
  92          ExpTimeZoneInfo.StandardBias);
  93
  94   DPRINT("New time zone bias: %d minutes\n",
  95          TimeZoneInformation->Bias);
  96   DPRINT("New time zone standard bias: %d minutes\n",
  97          TimeZoneInformation->StandardBias);
  98
  99   /* Get the local time */
 100   HalQueryRealTimeClock(&TimeFields);
 101   RtlTimeFieldsToTime(&TimeFields,
 102                       &LocalTime);
 103
 104   /* FIXME: Calculate transition dates */
 105
 106   ExpTimeZoneBias.QuadPart =
 107     ((LONGLONG)(TimeZoneInformation->Bias + TimeZoneInformation->StandardBias)) * TICKSPERMINUTE;
 108   ExpTimeZoneId = TIME_ZONE_ID_STANDARD;
 109
 110   memcpy(&ExpTimeZoneInfo,
 111          TimeZoneInformation,
 112          sizeof(TIME_ZONE_INFORMATION));
 113
 114   /* Set the new time zone information */
 115   SharedUserData->TimeZoneBias.High1Time = ExpTimeZoneBias.u.HighPart;
 116   SharedUserData->TimeZoneBias.High2Time = ExpTimeZoneBias.u.HighPart;
 117   SharedUserData->TimeZoneBias.LowPart = ExpTimeZoneBias.u.LowPart;
 118   SharedUserData->TimeZoneId = ExpTimeZoneId;
 119
 120   DPRINT("New time zone bias: %I64d minutes\n",
 121          ExpTimeZoneBias.QuadPart / TICKSPERMINUTE);
 122
 123   /* Calculate the new system time */
 124   ExLocalTimeToSystemTime(&LocalTime,
 125                           &SystemTime);
 126
 127   /* Set the new system time */
 128   KiSetSystemTime(&SystemTime);
 129
 130   DPRINT("ExpSetTimeZoneInformation() done\n");
 131
 132   return STATUS_SUCCESS;
 133 }
 134
 135
 136 /*
 137  * FUNCTION: Sets the system time.
 138  * PARAMETERS:
 139  *        NewTime - Points to a variable that specified the new time
 140  *        of day in the standard time format.
 141  *        OldTime - Optionally points to a variable that receives the
 142  *        old time of day in the standard time format.
 143  * RETURNS: Status
 144  */
 145 NTSTATUS STDCALL
 146 NtSetSystemTime(IN PLARGE_INTEGER SystemTime,
 147                 OUT PLARGE_INTEGER PreviousTime OPTIONAL)
 148 {
 149   LARGE_INTEGER OldSystemTime;
 150   LARGE_INTEGER NewSystemTime;
 151   LARGE_INTEGER LocalTime;
 152   TIME_FIELDS TimeFields;
 153   KPROCESSOR_MODE PreviousMode;
 154   NTSTATUS Status = STATUS_SUCCESS;
 155
 156   PAGED_CODE();
 157
 158   PreviousMode = ExGetPreviousMode();
 159
 160   if(PreviousMode != KernelMode)
 161   {
 162     _SEH_TRY
 163     {
 164       NewSystemTime = ProbeForReadLargeInteger(SystemTime);
 165       if(PreviousTime != NULL)
 166       {
 167         ProbeForWriteLargeInteger(PreviousTime);
 168       }
 169     }
 170     _SEH_EXCEPT(_SEH_ExSystemExceptionFilter)
 171     {
 172       Status = _SEH_GetExceptionCode();
 173     }
 174     _SEH_END;
 175
 176     if(!NT_SUCCESS(Status))
 177     {
 178       return Status;
 179     }
 180   }
 181   else
 182   {
 183     NewSystemTime = *SystemTime;
 184   }
 185
 186   if(!SeSinglePrivilegeCheck(SeSystemtimePrivilege,
 187                              PreviousMode))
 188   {
 189     DPRINT1("NtSetSystemTime: Caller requires the SeSystemtimePrivilege privilege!\n");
 190     return STATUS_PRIVILEGE_NOT_HELD;
 191   }
 192
 193   if(PreviousTime != NULL)
 194   {
 195     KeQuerySystemTime(&OldSystemTime);
 196   }
 197
 198   ExSystemTimeToLocalTime(&NewSystemTime,
 199                           &LocalTime);
 200   RtlTimeToTimeFields(&LocalTime,
 201                       &TimeFields);
 202   HalSetRealTimeClock(&TimeFields);
 203
 204   /* Set system time */
 205   KiSetSystemTime(&NewSystemTime);
 206
 207   if(PreviousTime != NULL)
 208   {
 209     _SEH_TRY
 210     {
 211       *PreviousTime = OldSystemTime;
 212     }
 213     _SEH_EXCEPT(_SEH_ExSystemExceptionFilter)
 214     {
 215       Status = _SEH_GetExceptionCode();
 216     }
 217     _SEH_END;
 218   }
 219
 220   return STATUS_SUCCESS;
 221 }
 222
 223
 224 /*
 225  * FUNCTION: Retrieves the system time.
 226  * PARAMETERS:
 227  *          CurrentTime - Points to a variable that receives the current
 228  *          time of day in the standard time format.
 229  */
 230 NTSTATUS STDCALL
 231 NtQuerySystemTime(OUT PLARGE_INTEGER SystemTime)
 232 {
 233   KPROCESSOR_MODE PreviousMode;
 234   NTSTATUS Status = STATUS_SUCCESS;
 235
 236   PAGED_CODE();
 237
 238   PreviousMode = ExGetPreviousMode();
 239
 240   if(PreviousMode != KernelMode)
 241   {
 242     _SEH_TRY
 243     {
 244       ProbeForWriteLargeInteger(SystemTime);
 245
 246       /* it's safe to pass the pointer directly to KeQuerySystemTime as it's just
 247          a basic copy to these pointer, if it raises an exception nothing dangerous
 248          can happen! */
 249       KeQuerySystemTime(SystemTime);
 250     }
 251     _SEH_EXCEPT(_SEH_ExSystemExceptionFilter)
 252     {
 253       Status = _SEH_GetExceptionCode();
 254     }
 255     _SEH_END;
 256   }
 257   else
 258   {
 259     KeQuerySystemTime(SystemTime);
 260   }
 261
 262   return Status;
 263 }
 264
 265
 266 /*
 267  * @implemented
 268  */
 269 VOID
 270 STDCALL
 271 ExLocalTimeToSystemTime (
 272         PLARGE_INTEGER  LocalTime,
 273         PLARGE_INTEGER  SystemTime
 274         )
 275 {
 276   SystemTime->QuadPart =
 277     LocalTime->QuadPart + ExpTimeZoneBias.QuadPart;
 278 }
 279
 280
 281 /*
 282  * @unimplemented
 283  */
 284 ULONG
 285 STDCALL
 286 ExSetTimerResolution (
 287     IN ULONG DesiredTime,
 288     IN BOOLEAN SetResolution
 289     )
 290 {
 291         UNIMPLEMENTED;
 292
 293     return 0;
 294 }
 295
 296
 297 /*
 298  * @implemented
 299  */
 300 VOID
 301 STDCALL
 302 ExSystemTimeToLocalTime (
 303         PLARGE_INTEGER  SystemTime,
 304         PLARGE_INTEGER  LocalTime
 305         )
 306 {
 307   LocalTime->QuadPart =
 308     SystemTime->QuadPart - ExpTimeZoneBias.QuadPart;
 309 }
 310
 311 /* EOF */