reactos/ntoskrnl/ps/i386/psldt.c

114 lines
3.1 KiB
C

/*
* PROJECT: ReactOS Kernel
* LICENSE: GPL - See COPYING in the top level directory
* FILE: ntoskrnl/ps/i386/psldt.c
* PURPOSE: LDT support for x86
* PROGRAMMERS: Stefan Ginsberg (stefan.ginsberg@reactos.org)
*/
/* INCLUDES ******************************************************************/
#include <ntoskrnl.h>
#define NDEBUG
#include <debug.h>
/* FUNCTIONS *****************************************************************/
VOID
NTAPI
PspDeleteLdt(PEPROCESS Process)
{
/* FIXME - LdtInformation must be null as long as we don't implement VDMs */
ASSERT(Process->LdtInformation == NULL);
}
VOID
NTAPI
PspDeleteVdmObjects(PEPROCESS Process)
{
/* If there are no VDM objects, just exit */
if (Process->VdmObjects == NULL)
return;
/* FIXME: Need to do more than just freeing the main VdmObjects member! */
UNIMPLEMENTED;
/* Free VDM objects */
ExFreePoolWithTag(Process->VdmObjects, ' eK');
Process->VdmObjects = NULL;
}
NTSTATUS
NTAPI
PspQueryDescriptorThread(IN PETHREAD Thread,
IN PVOID ThreadInformation,
IN ULONG ThreadInformationLength,
OUT PULONG ReturnLength OPTIONAL)
{
DESCRIPTOR_TABLE_ENTRY DescriptorEntry;
LDT_ENTRY Descriptor;
NTSTATUS Status;
PAGED_CODE();
/* Verify the size */
if (ThreadInformationLength != sizeof(DESCRIPTOR_TABLE_ENTRY))
{
/* Fail */
return STATUS_INFO_LENGTH_MISMATCH;
}
/* Enter SEH for the copy */
_SEH2_TRY
{
/* Get the descriptor */
RtlCopyMemory(&DescriptorEntry,
ThreadInformation,
sizeof(DESCRIPTOR_TABLE_ENTRY));
}
_SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
{
/* Return the exception code */
_SEH2_YIELD(return _SEH2_GetExceptionCode());
}
_SEH2_END;
/* Check if this is a GDT selector */
if (!(DescriptorEntry.Selector & 0x4))
{
/* Get the GDT entry */
Status = Ke386GetGdtEntryThread(&Thread->Tcb,
DescriptorEntry.Selector & 0xFFFFFFF8,
(PKGDTENTRY)&Descriptor);
if (!NT_SUCCESS(Status)) return Status;
/* Enter SEH for the copy */
_SEH2_TRY
{
/* Copy the GDT entry to caller */
RtlCopyMemory(&((PDESCRIPTOR_TABLE_ENTRY)ThreadInformation)->
Descriptor,
&Descriptor,
sizeof(LDT_ENTRY));
if (ReturnLength) *ReturnLength = sizeof(LDT_ENTRY);
}
_SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
{
/* Return the exception code */
_SEH2_YIELD(return _SEH2_GetExceptionCode());
}
_SEH2_END;
/* Success */
Status = STATUS_SUCCESS;
}
else
{
/* This is only supported for VDM, which we don't implement */
ASSERT(Thread->ThreadsProcess->LdtInformation == NULL);
Status = STATUS_NO_LDT;
}
/* Return status to caller */
return Status;
}