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  * PROGRAMMER:      David Welch (welch@mcmail.com)
   8  * UPDATE HISTORY:
   9  *                  Created 22/05/98
  10  */
  11
  12 /* INCLUDES *****************************************************************/
  13
  14 #include <ntoskrnl.h>
  15 #define NDEBUG
  16 #include <internal/debug.h>
  17
  18
  19 #define TICKSPERMINUTE  600000000
  20
  21 /* GLOBALS ******************************************************************/
  22
  23 /* Note: Bias[minutes] = UTC - local time */
  24 TIME_ZONE_INFORMATION ExpTimeZoneInfo;
  25 LARGE_INTEGER ExpTimeZoneBias;
  26 ULONG ExpTimeZoneId;
  27
  28
  29 /* FUNCTIONS ****************************************************************/
  30
  31 VOID INIT_FUNCTION
  32 ExpInitTimeZoneInfo(VOID)
  33 {
  34   LARGE_INTEGER CurrentTime;
  35   NTSTATUS Status;
  36
  37   /* Read time zone information from the registry */
  38   Status = RtlQueryTimeZoneInformation(&ExpTimeZoneInfo);
  39   if (!NT_SUCCESS(Status))
  40     {
  41       memset(&ExpTimeZoneInfo, 0, sizeof(TIME_ZONE_INFORMATION));
  42
  43       ExpTimeZoneBias.QuadPart = (LONGLONG)0;
  44       ExpTimeZoneId = TIME_ZONE_ID_UNKNOWN;
  45     }
  46   else
  47     {
  48       /* FIXME: Calculate transition dates */
  49
  50       ExpTimeZoneBias.QuadPart =
  51         ((LONGLONG)(ExpTimeZoneInfo.Bias + ExpTimeZoneInfo.StandardBias)) * TICKSPERMINUTE;
  52       ExpTimeZoneId = TIME_ZONE_ID_STANDARD;
  53     }
  54
  55   SharedUserData->TimeZoneBias.High1Time = ExpTimeZoneBias.u.HighPart;
  56   SharedUserData->TimeZoneBias.High2Time = ExpTimeZoneBias.u.HighPart;
  57   SharedUserData->TimeZoneBias.LowPart = ExpTimeZoneBias.u.LowPart;
  58   SharedUserData->TimeZoneId = ExpTimeZoneId;
  59
  60   /* Convert boot time from local time to UTC */
  61   SystemBootTime.QuadPart += ExpTimeZoneBias.QuadPart;
  62
  63   /* Convert sytem time from local time to UTC */
  64   do
  65     {
  66       CurrentTime.u.HighPart = SharedUserData->SystemTime.High1Time;
  67       CurrentTime.u.LowPart = SharedUserData->SystemTime.LowPart;
  68     }
  69   while (CurrentTime.u.HighPart != SharedUserData->SystemTime.High2Time);
  70
  71   CurrentTime.QuadPart += ExpTimeZoneBias.QuadPart;
  72
  73   SharedUserData->SystemTime.LowPart = CurrentTime.u.LowPart;
  74   SharedUserData->SystemTime.High1Time = CurrentTime.u.HighPart;
  75   SharedUserData->SystemTime.High2Time = CurrentTime.u.HighPart;
  76 }
  77
  78
  79 NTSTATUS
  80 ExpSetTimeZoneInformation(PTIME_ZONE_INFORMATION TimeZoneInformation)
  81 {
  82   LARGE_INTEGER LocalTime;
  83   LARGE_INTEGER SystemTime;
  84   TIME_FIELDS TimeFields;
  85
  86   DPRINT("ExpSetTimeZoneInformation() called\n");
  87
  88   DPRINT("Old time zone bias: %d minutes\n",
  89          ExpTimeZoneInfo.Bias);
  90   DPRINT("Old time zone standard bias: %d minutes\n",
  91          ExpTimeZoneInfo.StandardBias);
  92
  93   DPRINT("New time zone bias: %d minutes\n",
  94          TimeZoneInformation->Bias);
  95   DPRINT("New time zone standard bias: %d minutes\n",
  96          TimeZoneInformation->StandardBias);
  97
  98   /* Get the local time */
  99   HalQueryRealTimeClock(&TimeFields);
 100   RtlTimeFieldsToTime(&TimeFields,
 101                       &LocalTime);
 102
 103   /* FIXME: Calculate transition dates */
 104
 105   ExpTimeZoneBias.QuadPart =
 106     ((LONGLONG)(TimeZoneInformation->Bias + TimeZoneInformation->StandardBias)) * TICKSPERMINUTE;
 107   ExpTimeZoneId = TIME_ZONE_ID_STANDARD;
 108
 109   memcpy(&ExpTimeZoneInfo,
 110          TimeZoneInformation,
 111          sizeof(TIME_ZONE_INFORMATION));
 112
 113   /* Set the new time zone information */
 114   SharedUserData->TimeZoneBias.High1Time = ExpTimeZoneBias.u.HighPart;
 115   SharedUserData->TimeZoneBias.High2Time = ExpTimeZoneBias.u.HighPart;
 116   SharedUserData->TimeZoneBias.LowPart = ExpTimeZoneBias.u.LowPart;
 117   SharedUserData->TimeZoneId = ExpTimeZoneId;
 118
 119   DPRINT("New time zone bias: %I64d minutes\n",
 120          ExpTimeZoneBias.QuadPart / TICKSPERMINUTE);
 121
 122   /* Calculate the new system time */
 123   ExLocalTimeToSystemTime(&LocalTime,
 124                           &SystemTime);
 125
 126   /* Set the new system time */
 127   KiSetSystemTime(&SystemTime);
 128
 129   DPRINT("ExpSetTimeZoneInformation() done\n");
 130
 131   return STATUS_SUCCESS;
 132 }
 133
 134
 135 /*
 136  * FUNCTION: Sets the system time.
 137  * PARAMETERS:
 138  *        NewTime - Points to a variable that specified the new time
 139  *        of day in the standard time format.
 140  *        OldTime - Optionally points to a variable that receives the
 141  *        old time of day in the standard time format.
 142  * RETURNS: Status
 143  */
 144 NTSTATUS STDCALL
 145 NtSetSystemTime(IN PLARGE_INTEGER SystemTime,
 146                 OUT PLARGE_INTEGER PreviousTime OPTIONAL)
 147 {
 148   LARGE_INTEGER OldSystemTime;
 149   LARGE_INTEGER NewSystemTime;
 150   LARGE_INTEGER LocalTime;
 151   TIME_FIELDS TimeFields;
 152   KPROCESSOR_MODE PreviousMode;
 153   NTSTATUS Status = STATUS_SUCCESS;
 154
 155   PreviousMode = ExGetPreviousMode();
 156
 157   if(PreviousMode != KernelMode)
 158   {
 159     _SEH_TRY
 160     {
 161       ProbeForRead(SystemTime,
 162                    sizeof(LARGE_INTEGER),
 163                    sizeof(ULONG));
 164       NewSystemTime = *SystemTime;
 165       if(PreviousTime != NULL)
 166       {
 167         ProbeForWrite(PreviousTime,
 168                       sizeof(LARGE_INTEGER),
 169                       sizeof(ULONG));
 170       }
 171     }
 172     _SEH_HANDLE
 173     {
 174       Status = _SEH_GetExceptionCode();
 175     }
 176     _SEH_END;
 177
 178     if(!NT_SUCCESS(Status))
 179     {
 180       return Status;
 181     }
 182   }
 183   else
 184   {
 185     NewSystemTime = *SystemTime;
 186   }
 187
 188   if(!SeSinglePrivilegeCheck(SeSystemtimePrivilege,
 189                              PreviousMode))
 190   {
 191     DPRINT1("NtSetSystemTime: Caller requires the SeSystemtimePrivilege privilege!\n");
 192     return STATUS_PRIVILEGE_NOT_HELD;
 193   }
 194
 195   if(PreviousTime != NULL)
 196   {
 197     KeQuerySystemTime(&OldSystemTime);
 198   }
 199
 200   ExSystemTimeToLocalTime(&NewSystemTime,
 201                           &LocalTime);
 202   RtlTimeToTimeFields(&LocalTime,
 203                       &TimeFields);
 204   HalSetRealTimeClock(&TimeFields);
 205
 206   /* Set system time */
 207   KiSetSystemTime(&NewSystemTime);
 208
 209   if(PreviousTime != NULL)
 210   {
 211     _SEH_TRY
 212     {
 213       *PreviousTime = OldSystemTime;
 214     }
 215     _SEH_HANDLE
 216     {
 217       Status = _SEH_GetExceptionCode();
 218     }
 219     _SEH_END;
 220   }
 221
 222   return STATUS_SUCCESS;
 223 }
 224
 225
 226 /*
 227  * FUNCTION: Retrieves the system time.
 228  * PARAMETERS:
 229  *          CurrentTime - Points to a variable that receives the current
 230  *          time of day in the standard time format.
 231  */
 232 NTSTATUS STDCALL
 233 NtQuerySystemTime(OUT PLARGE_INTEGER SystemTime)
 234 {
 235   KPROCESSOR_MODE PreviousMode;
 236   NTSTATUS Status = STATUS_SUCCESS;
 237
 238   PreviousMode = ExGetPreviousMode();
 239
 240   if(PreviousMode != KernelMode)
 241   {
 242     _SEH_TRY
 243     {
 244       ProbeForRead(SystemTime,
 245                    sizeof(LARGE_INTEGER),
 246                    sizeof(ULONG));
 247
 248       /* it's safe to pass the pointer directly to KeQuerySystemTime as it's just
 249          a basic copy to these pointer, if it raises an exception nothing dangerous
 250          can happen! */
 251       KeQuerySystemTime(SystemTime);
 252     }
 253     _SEH_HANDLE
 254     {
 255       Status = _SEH_GetExceptionCode();
 256     }
 257     _SEH_END;
 258   }
 259   else
 260   {
 261     KeQuerySystemTime(SystemTime);
 262   }
 263
 264   return Status;
 265 }
 266
 267
 268 /*
 269  * @implemented
 270  */
 271 VOID
 272 STDCALL
 273 ExLocalTimeToSystemTime (
 274         PLARGE_INTEGER  LocalTime,
 275         PLARGE_INTEGER  SystemTime
 276         )
 277 {
 278   SystemTime->QuadPart =
 279     LocalTime->QuadPart + ExpTimeZoneBias.QuadPart;
 280 }
 281
 282
 283 /*
 284  * @unimplemented
 285  */
 286 ULONG
 287 STDCALL
 288 ExSetTimerResolution (
 289     IN ULONG DesiredTime,
 290     IN BOOLEAN SetResolution
 291     )
 292 {
 293         UNIMPLEMENTED;
 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 */