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 INIT_FUNCTION
  31 ExpInitTimeZoneInfo(VOID)
  32 {
  33   LARGE_INTEGER CurrentTime;
  34   NTSTATUS Status;
  35
  36   /* Read time zone information from the registry */
  37   Status = RtlQueryTimeZoneInformation(&ExpTimeZoneInfo);
  38   if (!NT_SUCCESS(Status))
  39     {
  40       memset(&ExpTimeZoneInfo, 0, sizeof(TIME_ZONE_INFORMATION));
  41
  42       ExpTimeZoneBias.QuadPart = (LONGLONG)0;
  43       ExpTimeZoneId = TIME_ZONE_ID_UNKNOWN;
  44     }
  45   else
  46     {
  47       /* FIXME: Calculate transition dates */
  48
  49       ExpTimeZoneBias.QuadPart =
  50         ((LONGLONG)(ExpTimeZoneInfo.Bias + ExpTimeZoneInfo.StandardBias)) * TICKSPERMINUTE;
  51       ExpTimeZoneId = TIME_ZONE_ID_STANDARD;
  52     }
  53
  54   SharedUserData->TimeZoneBias.High1Time = ExpTimeZoneBias.u.HighPart;
  55   SharedUserData->TimeZoneBias.High2Time = ExpTimeZoneBias.u.HighPart;
  56   SharedUserData->TimeZoneBias.LowPart = ExpTimeZoneBias.u.LowPart;
  57   SharedUserData->TimeZoneId = ExpTimeZoneId;
  58
  59   /* Convert boot time from local time to UTC */
  60   SystemBootTime.QuadPart += ExpTimeZoneBias.QuadPart;
  61
  62   /* Convert sytem time from local time to UTC */
  63   do
  64     {
  65       CurrentTime.u.HighPart = SharedUserData->SystemTime.High1Time;
  66       CurrentTime.u.LowPart = SharedUserData->SystemTime.LowPart;
  67     }
  68   while (CurrentTime.u.HighPart != SharedUserData->SystemTime.High2Time);
  69
  70   CurrentTime.QuadPart += ExpTimeZoneBias.QuadPart;
  71
  72   SharedUserData->SystemTime.LowPart = CurrentTime.u.LowPart;
  73   SharedUserData->SystemTime.High1Time = CurrentTime.u.HighPart;
  74   SharedUserData->SystemTime.High2Time = CurrentTime.u.HighPart;
  75 }
  76
  77
  78 NTSTATUS
  79 ExpSetTimeZoneInformation(PTIME_ZONE_INFORMATION TimeZoneInformation)
  80 {
  81   LARGE_INTEGER LocalTime;
  82   LARGE_INTEGER SystemTime;
  83   TIME_FIELDS TimeFields;
  84
  85   DPRINT("ExpSetTimeZoneInformation() called\n");
  86
  87   DPRINT("Old time zone bias: %d minutes\n",
  88          ExpTimeZoneInfo.Bias);
  89   DPRINT("Old time zone standard bias: %d minutes\n",
  90          ExpTimeZoneInfo.StandardBias);
  91
  92   DPRINT("New time zone bias: %d minutes\n",
  93          TimeZoneInformation->Bias);
  94   DPRINT("New time zone standard bias: %d minutes\n",
  95          TimeZoneInformation->StandardBias);
  96
  97   /* Get the local time */
  98   HalQueryRealTimeClock(&TimeFields);
  99   RtlTimeFieldsToTime(&TimeFields,
 100                       &LocalTime);
 101
 102   /* FIXME: Calculate transition dates */
 103
 104   ExpTimeZoneBias.QuadPart =
 105     ((LONGLONG)(TimeZoneInformation->Bias + TimeZoneInformation->StandardBias)) * TICKSPERMINUTE;
 106   ExpTimeZoneId = TIME_ZONE_ID_STANDARD;
 107
 108   memcpy(&ExpTimeZoneInfo,
 109          TimeZoneInformation,
 110          sizeof(TIME_ZONE_INFORMATION));
 111
 112   /* Set the new time zone information */
 113   SharedUserData->TimeZoneBias.High1Time = ExpTimeZoneBias.u.HighPart;
 114   SharedUserData->TimeZoneBias.High2Time = ExpTimeZoneBias.u.HighPart;
 115   SharedUserData->TimeZoneBias.LowPart = ExpTimeZoneBias.u.LowPart;
 116   SharedUserData->TimeZoneId = ExpTimeZoneId;
 117
 118   DPRINT("New time zone bias: %I64d minutes\n",
 119          ExpTimeZoneBias.QuadPart / TICKSPERMINUTE);
 120
 121   /* Calculate the new system time */
 122   ExLocalTimeToSystemTime(&LocalTime,
 123                           &SystemTime);
 124
 125   /* Set the new system time */
 126   KiSetSystemTime(&SystemTime);
 127
 128   DPRINT("ExpSetTimeZoneInformation() done\n");
 129
 130   return STATUS_SUCCESS;
 131 }
 132
 133
 134 /*
 135  * FUNCTION: Sets the system time.
 136  * PARAMETERS:
 137  *        NewTime - Points to a variable that specified the new time
 138  *        of day in the standard time format.
 139  *        OldTime - Optionally points to a variable that receives the
 140  *        old time of day in the standard time format.
 141  * RETURNS: Status
 142  */
 143 NTSTATUS STDCALL
 144 NtSetSystemTime(IN PLARGE_INTEGER SystemTime,
 145                 OUT PLARGE_INTEGER PreviousTime OPTIONAL)
 146 {
 147   LARGE_INTEGER OldSystemTime;
 148   LARGE_INTEGER NewSystemTime;
 149   LARGE_INTEGER LocalTime;
 150   TIME_FIELDS TimeFields;
 151   KPROCESSOR_MODE PreviousMode;
 152   NTSTATUS Status = STATUS_SUCCESS;
 153
 154   PAGED_CODE();
 155
 156   PreviousMode = ExGetPreviousMode();
 157
 158   if(PreviousMode != KernelMode)
 159   {
 160     _SEH_TRY
 161     {
 162       ProbeForRead(SystemTime,
 163                    sizeof(LARGE_INTEGER),
 164                    sizeof(ULONG));
 165       NewSystemTime = *SystemTime;
 166       if(PreviousTime != NULL)
 167       {
 168         ProbeForWrite(PreviousTime,
 169                       sizeof(LARGE_INTEGER),
 170                       sizeof(ULONG));
 171       }
 172     }
 173     _SEH_HANDLE
 174     {
 175       Status = _SEH_GetExceptionCode();
 176     }
 177     _SEH_END;
 178
 179     if(!NT_SUCCESS(Status))
 180     {
 181       return Status;
 182     }
 183   }
 184   else
 185   {
 186     NewSystemTime = *SystemTime;
 187   }
 188
 189   if(!SeSinglePrivilegeCheck(SeSystemtimePrivilege,
 190                              PreviousMode))
 191   {
 192     DPRINT1("NtSetSystemTime: Caller requires the SeSystemtimePrivilege privilege!\n");
 193     return STATUS_PRIVILEGE_NOT_HELD;
 194   }
 195
 196   if(PreviousTime != NULL)
 197   {
 198     KeQuerySystemTime(&OldSystemTime);
 199   }
 200
 201   ExSystemTimeToLocalTime(&NewSystemTime,
 202                           &LocalTime);
 203   RtlTimeToTimeFields(&LocalTime,
 204                       &TimeFields);
 205   HalSetRealTimeClock(&TimeFields);
 206
 207   /* Set system time */
 208   KiSetSystemTime(&NewSystemTime);
 209
 210   if(PreviousTime != NULL)
 211   {
 212     _SEH_TRY
 213     {
 214       *PreviousTime = OldSystemTime;
 215     }
 216     _SEH_HANDLE
 217     {
 218       Status = _SEH_GetExceptionCode();
 219     }
 220     _SEH_END;
 221   }
 222
 223   return STATUS_SUCCESS;
 224 }
 225
 226
 227 /*
 228  * FUNCTION: Retrieves the system time.
 229  * PARAMETERS:
 230  *          CurrentTime - Points to a variable that receives the current
 231  *          time of day in the standard time format.
 232  */
 233 NTSTATUS STDCALL
 234 NtQuerySystemTime(OUT PLARGE_INTEGER SystemTime)
 235 {
 236   KPROCESSOR_MODE PreviousMode;
 237   NTSTATUS Status = STATUS_SUCCESS;
 238
 239   PAGED_CODE();
 240
 241   PreviousMode = ExGetPreviousMode();
 242
 243   if(PreviousMode != KernelMode)
 244   {
 245     _SEH_TRY
 246     {
 247       ProbeForRead(SystemTime,
 248                    sizeof(LARGE_INTEGER),
 249                    sizeof(ULONG));
 250
 251       /* it's safe to pass the pointer directly to KeQuerySystemTime as it's just
 252          a basic copy to these pointer, if it raises an exception nothing dangerous
 253          can happen! */
 254       KeQuerySystemTime(SystemTime);
 255     }
 256     _SEH_HANDLE
 257     {
 258       Status = _SEH_GetExceptionCode();
 259     }
 260     _SEH_END;
 261   }
 262   else
 263   {
 264     KeQuerySystemTime(SystemTime);
 265   }
 266
 267   return Status;
 268 }
 269
 270
 271 /*
 272  * @implemented
 273  */
 274 VOID
 275 STDCALL
 276 ExLocalTimeToSystemTime (
 277         PLARGE_INTEGER  LocalTime,
 278         PLARGE_INTEGER  SystemTime
 279         )
 280 {
 281   SystemTime->QuadPart =
 282     LocalTime->QuadPart + ExpTimeZoneBias.QuadPart;
 283 }
 284
 285
 286 /*
 287  * @unimplemented
 288  */
 289 ULONG
 290 STDCALL
 291 ExSetTimerResolution (
 292     IN ULONG DesiredTime,
 293     IN BOOLEAN SetResolution
 294     )
 295 {
 296         UNIMPLEMENTED;
 297
 298     return 0;
 299 }
 300
 301
 302 /*
 303  * @implemented
 304  */
 305 VOID
 306 STDCALL
 307 ExSystemTimeToLocalTime (
 308         PLARGE_INTEGER  SystemTime,
 309         PLARGE_INTEGER  LocalTime
 310         )
 311 {
 312   LocalTime->QuadPart =
 313     SystemTime->QuadPart - ExpTimeZoneBias.QuadPart;
 314 }
 315
 316 /* EOF */