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       ProbeForRead(SystemTime,
 165                    sizeof(LARGE_INTEGER),
 166                    sizeof(ULONG));
 167       NewSystemTime = *SystemTime;
 168       if(PreviousTime != NULL)
 169       {
 170         ProbeForWrite(PreviousTime,
 171                       sizeof(LARGE_INTEGER),
 172                       sizeof(ULONG));
 173       }
 174     }
 175     _SEH_EXCEPT(_SEH_ExSystemExceptionFilter)
 176     {
 177       Status = _SEH_GetExceptionCode();
 178     }
 179     _SEH_END;
 180
 181     if(!NT_SUCCESS(Status))
 182     {
 183       return Status;
 184     }
 185   }
 186   else
 187   {
 188     NewSystemTime = *SystemTime;
 189   }
 190
 191   if(!SeSinglePrivilegeCheck(SeSystemtimePrivilege,
 192                              PreviousMode))
 193   {
 194     DPRINT1("NtSetSystemTime: Caller requires the SeSystemtimePrivilege privilege!\n");
 195     return STATUS_PRIVILEGE_NOT_HELD;
 196   }
 197
 198   if(PreviousTime != NULL)
 199   {
 200     KeQuerySystemTime(&OldSystemTime);
 201   }
 202
 203   ExSystemTimeToLocalTime(&NewSystemTime,
 204                           &LocalTime);
 205   RtlTimeToTimeFields(&LocalTime,
 206                       &TimeFields);
 207   HalSetRealTimeClock(&TimeFields);
 208
 209   /* Set system time */
 210   KiSetSystemTime(&NewSystemTime);
 211
 212   if(PreviousTime != NULL)
 213   {
 214     _SEH_TRY
 215     {
 216       *PreviousTime = OldSystemTime;
 217     }
 218     _SEH_EXCEPT(_SEH_ExSystemExceptionFilter)
 219     {
 220       Status = _SEH_GetExceptionCode();
 221     }
 222     _SEH_END;
 223   }
 224
 225   return STATUS_SUCCESS;
 226 }
 227
 228
 229 /*
 230  * FUNCTION: Retrieves the system time.
 231  * PARAMETERS:
 232  *          CurrentTime - Points to a variable that receives the current
 233  *          time of day in the standard time format.
 234  */
 235 NTSTATUS STDCALL
 236 NtQuerySystemTime(OUT PLARGE_INTEGER SystemTime)
 237 {
 238   KPROCESSOR_MODE PreviousMode;
 239   NTSTATUS Status = STATUS_SUCCESS;
 240
 241   PAGED_CODE();
 242
 243   PreviousMode = ExGetPreviousMode();
 244
 245   if(PreviousMode != KernelMode)
 246   {
 247     _SEH_TRY
 248     {
 249       ProbeForRead(SystemTime,
 250                    sizeof(LARGE_INTEGER),
 251                    sizeof(ULONG));
 252
 253       /* it's safe to pass the pointer directly to KeQuerySystemTime as it's just
 254          a basic copy to these pointer, if it raises an exception nothing dangerous
 255          can happen! */
 256       KeQuerySystemTime(SystemTime);
 257     }
 258     _SEH_EXCEPT(_SEH_ExSystemExceptionFilter)
 259     {
 260       Status = _SEH_GetExceptionCode();
 261     }
 262     _SEH_END;
 263   }
 264   else
 265   {
 266     KeQuerySystemTime(SystemTime);
 267   }
 268
 269   return Status;
 270 }
 271
 272
 273 /*
 274  * @implemented
 275  */
 276 VOID
 277 STDCALL
 278 ExLocalTimeToSystemTime (
 279         PLARGE_INTEGER  LocalTime,
 280         PLARGE_INTEGER  SystemTime
 281         )
 282 {
 283   SystemTime->QuadPart =
 284     LocalTime->QuadPart + ExpTimeZoneBias.QuadPart;
 285 }
 286
 287
 288 /*
 289  * @unimplemented
 290  */
 291 ULONG
 292 STDCALL
 293 ExSetTimerResolution (
 294     IN ULONG DesiredTime,
 295     IN BOOLEAN SetResolution
 296     )
 297 {
 298         UNIMPLEMENTED;
 299
 300     return 0;
 301 }
 302
 303
 304 /*
 305  * @implemented
 306  */
 307 VOID
 308 STDCALL
 309 ExSystemTimeToLocalTime (
 310         PLARGE_INTEGER  SystemTime,
 311         PLARGE_INTEGER  LocalTime
 312         )
 313 {
 314   LocalTime->QuadPart =
 315     SystemTime->QuadPart - ExpTimeZoneBias.QuadPart;
 316 }
 317
 318 /* EOF */