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 #if defined (ALLOC_PRAGMA)
  21 #pragma alloc_text(INIT, ExpInitTimeZoneInfo)
  22 #endif
  23
  24 /* GLOBALS ******************************************************************/
  25
  26 /* Note: Bias[minutes] = UTC - local time */
  27 TIME_ZONE_INFORMATION ExpTimeZoneInfo;
  28 LARGE_INTEGER ExpTimeZoneBias;
  29 ULONG ExpTimeZoneId;
  30
  31
  32 /* FUNCTIONS ****************************************************************/
  33
  34 VOID
  35 INIT_FUNCTION
  36 STDCALL
  37 ExpInitTimeZoneInfo(VOID)
  38 {
  39   LARGE_INTEGER CurrentTime;
  40   NTSTATUS Status;
  41
  42   /* Read time zone information from the registry */
  43   Status = RtlQueryTimeZoneInformation(&ExpTimeZoneInfo);
  44   if (!NT_SUCCESS(Status))
  45     {
  46       memset(&ExpTimeZoneInfo, 0, sizeof(TIME_ZONE_INFORMATION));
  47
  48       ExpTimeZoneBias.QuadPart = (LONGLONG)0;
  49       ExpTimeZoneId = TIME_ZONE_ID_UNKNOWN;
  50     }
  51   else
  52     {
  53       /* FIXME: Calculate transition dates */
  54
  55       ExpTimeZoneBias.QuadPart =
  56         ((LONGLONG)(ExpTimeZoneInfo.Bias + ExpTimeZoneInfo.StandardBias)) * TICKSPERMINUTE;
  57       ExpTimeZoneId = TIME_ZONE_ID_STANDARD;
  58     }
  59
  60   SharedUserData->TimeZoneBias.High1Time = ExpTimeZoneBias.u.HighPart;
  61   SharedUserData->TimeZoneBias.High2Time = ExpTimeZoneBias.u.HighPart;
  62   SharedUserData->TimeZoneBias.LowPart = ExpTimeZoneBias.u.LowPart;
  63   SharedUserData->TimeZoneId = ExpTimeZoneId;
  64
  65   /* Convert boot time from local time to UTC */
  66   SystemBootTime.QuadPart += ExpTimeZoneBias.QuadPart;
  67
  68   /* Convert sytem time from local time to UTC */
  69   do
  70     {
  71       CurrentTime.u.HighPart = SharedUserData->SystemTime.High1Time;
  72       CurrentTime.u.LowPart = SharedUserData->SystemTime.LowPart;
  73     }
  74   while (CurrentTime.u.HighPart != SharedUserData->SystemTime.High2Time);
  75
  76   CurrentTime.QuadPart += ExpTimeZoneBias.QuadPart;
  77
  78   SharedUserData->SystemTime.LowPart = CurrentTime.u.LowPart;
  79   SharedUserData->SystemTime.High1Time = CurrentTime.u.HighPart;
  80   SharedUserData->SystemTime.High2Time = CurrentTime.u.HighPart;
  81 }
  82
  83
  84 NTSTATUS
  85 ExpSetTimeZoneInformation(PTIME_ZONE_INFORMATION TimeZoneInformation)
  86 {
  87   LARGE_INTEGER LocalTime;
  88   LARGE_INTEGER SystemTime;
  89   TIME_FIELDS TimeFields;
  90
  91   DPRINT("ExpSetTimeZoneInformation() called\n");
  92
  93   DPRINT("Old time zone bias: %d minutes\n",
  94          ExpTimeZoneInfo.Bias);
  95   DPRINT("Old time zone standard bias: %d minutes\n",
  96          ExpTimeZoneInfo.StandardBias);
  97
  98   DPRINT("New time zone bias: %d minutes\n",
  99          TimeZoneInformation->Bias);
 100   DPRINT("New time zone standard bias: %d minutes\n",
 101          TimeZoneInformation->StandardBias);
 102
 103   /* Get the local time */
 104   HalQueryRealTimeClock(&TimeFields);
 105   RtlTimeFieldsToTime(&TimeFields,
 106                       &LocalTime);
 107
 108   /* FIXME: Calculate transition dates */
 109
 110   ExpTimeZoneBias.QuadPart =
 111     ((LONGLONG)(TimeZoneInformation->Bias + TimeZoneInformation->StandardBias)) * TICKSPERMINUTE;
 112   ExpTimeZoneId = TIME_ZONE_ID_STANDARD;
 113
 114   memcpy(&ExpTimeZoneInfo,
 115          TimeZoneInformation,
 116          sizeof(TIME_ZONE_INFORMATION));
 117
 118   /* Set the new time zone information */
 119   SharedUserData->TimeZoneBias.High1Time = ExpTimeZoneBias.u.HighPart;
 120   SharedUserData->TimeZoneBias.High2Time = ExpTimeZoneBias.u.HighPart;
 121   SharedUserData->TimeZoneBias.LowPart = ExpTimeZoneBias.u.LowPart;
 122   SharedUserData->TimeZoneId = ExpTimeZoneId;
 123
 124   DPRINT("New time zone bias: %I64d minutes\n",
 125          ExpTimeZoneBias.QuadPart / TICKSPERMINUTE);
 126
 127   /* Calculate the new system time */
 128   ExLocalTimeToSystemTime(&LocalTime,
 129                           &SystemTime);
 130
 131   /* Set the new system time */
 132   KiSetSystemTime(&SystemTime);
 133
 134   DPRINT("ExpSetTimeZoneInformation() done\n");
 135
 136   return STATUS_SUCCESS;
 137 }
 138
 139
 140 /*
 141  * FUNCTION: Sets the system time.
 142  * PARAMETERS:
 143  *        NewTime - Points to a variable that specified the new time
 144  *        of day in the standard time format.
 145  *        OldTime - Optionally points to a variable that receives the
 146  *        old time of day in the standard time format.
 147  * RETURNS: Status
 148  */
 149 NTSTATUS STDCALL
 150 NtSetSystemTime(IN PLARGE_INTEGER SystemTime,
 151                 OUT PLARGE_INTEGER PreviousTime OPTIONAL)
 152 {
 153   LARGE_INTEGER OldSystemTime;
 154   LARGE_INTEGER NewSystemTime;
 155   LARGE_INTEGER LocalTime;
 156   TIME_FIELDS TimeFields;
 157   KPROCESSOR_MODE PreviousMode;
 158   NTSTATUS Status = STATUS_SUCCESS;
 159
 160   PAGED_CODE();
 161
 162   PreviousMode = ExGetPreviousMode();
 163
 164   if(PreviousMode != KernelMode)
 165   {
 166     _SEH_TRY
 167     {
 168       NewSystemTime = ProbeForReadLargeInteger(SystemTime);
 169       if(PreviousTime != NULL)
 170       {
 171         ProbeForWriteLargeInteger(PreviousTime);
 172       }
 173     }
 174     _SEH_EXCEPT(_SEH_ExSystemExceptionFilter)
 175     {
 176       Status = _SEH_GetExceptionCode();
 177     }
 178     _SEH_END;
 179
 180     if(!NT_SUCCESS(Status))
 181     {
 182       return Status;
 183     }
 184   }
 185   else
 186   {
 187     NewSystemTime = *SystemTime;
 188   }
 189
 190   if(!SeSinglePrivilegeCheck(SeSystemtimePrivilege,
 191                              PreviousMode))
 192   {
 193     DPRINT1("NtSetSystemTime: Caller requires the SeSystemtimePrivilege privilege!\n");
 194     return STATUS_PRIVILEGE_NOT_HELD;
 195   }
 196
 197   if(PreviousTime != NULL)
 198   {
 199     KeQuerySystemTime(&OldSystemTime);
 200   }
 201
 202   ExSystemTimeToLocalTime(&NewSystemTime,
 203                           &LocalTime);
 204   RtlTimeToTimeFields(&LocalTime,
 205                       &TimeFields);
 206   HalSetRealTimeClock(&TimeFields);
 207
 208   /* Set system time */
 209   KiSetSystemTime(&NewSystemTime);
 210
 211   if(PreviousTime != NULL)
 212   {
 213     _SEH_TRY
 214     {
 215       *PreviousTime = OldSystemTime;
 216     }
 217     _SEH_EXCEPT(_SEH_ExSystemExceptionFilter)
 218     {
 219       Status = _SEH_GetExceptionCode();
 220     }
 221     _SEH_END;
 222   }
 223
 224   return STATUS_SUCCESS;
 225 }
 226
 227
 228 /*
 229  * FUNCTION: Retrieves the system time.
 230  * PARAMETERS:
 231  *          CurrentTime - Points to a variable that receives the current
 232  *          time of day in the standard time format.
 233  */
 234 NTSTATUS STDCALL
 235 NtQuerySystemTime(OUT PLARGE_INTEGER SystemTime)
 236 {
 237   KPROCESSOR_MODE PreviousMode;
 238   NTSTATUS Status = STATUS_SUCCESS;
 239
 240   PAGED_CODE();
 241
 242   PreviousMode = ExGetPreviousMode();
 243
 244   if(PreviousMode != KernelMode)
 245   {
 246     _SEH_TRY
 247     {
 248       ProbeForWriteLargeInteger(SystemTime);
 249
 250       /* it's safe to pass the pointer directly to KeQuerySystemTime as it's just
 251          a basic copy to these pointer, if it raises an exception nothing dangerous
 252          can happen! */
 253       KeQuerySystemTime(SystemTime);
 254     }
 255     _SEH_EXCEPT(_SEH_ExSystemExceptionFilter)
 256     {
 257       Status = _SEH_GetExceptionCode();
 258     }
 259     _SEH_END;
 260   }
 261   else
 262   {
 263     KeQuerySystemTime(SystemTime);
 264   }
 265
 266   return Status;
 267 }
 268
 269
 270 /*
 271  * @implemented
 272  */
 273 VOID
 274 STDCALL
 275 ExLocalTimeToSystemTime (
 276         PLARGE_INTEGER  LocalTime,
 277         PLARGE_INTEGER  SystemTime
 278         )
 279 {
 280   SystemTime->QuadPart =
 281     LocalTime->QuadPart + ExpTimeZoneBias.QuadPart;
 282 }
 283
 284
 285 /*
 286  * @unimplemented
 287  */
 288 ULONG
 289 STDCALL
 290 ExSetTimerResolution (
 291     IN ULONG DesiredTime,
 292     IN BOOLEAN SetResolution
 293     )
 294 {
 295         UNIMPLEMENTED;
 296
 297     return 0;
 298 }
 299
 300
 301 /*
 302  * @implemented
 303  */
 304 VOID
 305 STDCALL
 306 ExSystemTimeToLocalTime (
 307         PLARGE_INTEGER  SystemTime,
 308         PLARGE_INTEGER  LocalTime
 309         )
 310 {
 311   LocalTime->QuadPart =
 312     SystemTime->QuadPart - ExpTimeZoneBias.QuadPart;
 313 }
 314
 315 /* EOF */