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Implemented RtlExtendedMagicDivide() and RtlSelfRelativeToAbsoluteSD(). Patch by Marc Schuetz.

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svn path=/trunk/; revision=4815
This commit is contained in:
Eric Kohl 2003-06-01 18:14:24 +00:00
parent b036cea0eb
commit 25758f18d9
2 changed files with 120 additions and 9 deletions
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71
reactos/lib/ntdll/rtl/largeint.c
View file

@ -1,4 +1,4 @@
/* $Id: largeint.c,v 1.10 2002/12/08 15:57:39 robd Exp $
/* $Id: largeint.c,v 1.11 2003/06/01 18:14:24 ekohl Exp $
*
* COPYRIGHT: See COPYING in the top level directory
* PROJECT: ReactOS kernel
@ -119,14 +119,77 @@ RtlExtendedLargeIntegerDivide (
return RC;
}
LARGE_INTEGER
STDCALL
/******************************************************************************
* RtlExtendedMagicDivide
*
* Allows replacing a division by a longlong constant with a multiplication by
* the inverse constant.
*
* RETURNS
* (Dividend * MagicDivisor) >> (64 + ShiftCount)
*
* NOTES
* If the divisor of a division is constant, the constants MagicDivisor and
* shift must be chosen such that
* MagicDivisor = 2^(64 + ShiftCount) / Divisor.
*
* Then we have RtlExtendedMagicDivide(Dividend,MagicDivisor,ShiftCount) ==
* Dividend * MagicDivisor / 2^(64 + ShiftCount) == Dividend / Divisor.
*
* The Parameter MagicDivisor although defined as LONGLONG is used as
* ULONGLONG.
*/
#define LOWER_32(A) ((A) & 0xffffffff)
#define UPPER_32(A) ((A) >> 32)
LARGE_INTEGER STDCALL
RtlExtendedMagicDivide (LARGE_INTEGER Dividend,
LARGE_INTEGER MagicDivisor,
CCHAR ShiftCount)
{
UNIMPLEMENTED;
ULONGLONG dividend_high;
ULONGLONG dividend_low;
ULONGLONG inverse_divisor_high;
ULONGLONG inverse_divisor_low;
ULONGLONG ah_bl;
ULONGLONG al_bh;
LARGE_INTEGER result;
BOOLEAN positive;
if (Dividend.QuadPart < 0)
{
dividend_high = UPPER_32((ULONGLONG) -Dividend.QuadPart);
dividend_low = LOWER_32((ULONGLONG) -Dividend.QuadPart);
positive = FALSE;
}
else
{
dividend_high = UPPER_32((ULONGLONG) Dividend.QuadPart);
dividend_low = LOWER_32((ULONGLONG) Dividend.QuadPart);
positive = TRUE;
}
inverse_divisor_high = UPPER_32((ULONGLONG) MagicDivisor.QuadPart);
inverse_divisor_low = LOWER_32((ULONGLONG) MagicDivisor.QuadPart);
ah_bl = dividend_high * inverse_divisor_low;
al_bh = dividend_low * inverse_divisor_high;
result.QuadPart =
(LONGLONG) ((dividend_high * inverse_divisor_high +
UPPER_32(ah_bl) +
UPPER_32(al_bh) +
UPPER_32(LOWER_32(ah_bl) + LOWER_32(al_bh) +
UPPER_32(dividend_low * inverse_divisor_low))) >> ShiftCount);
if (!positive)
{
result.QuadPart = -result.QuadPart;
}
return result;
}
LARGE_INTEGER
STDCALL

52
reactos/lib/ntdll/rtl/sd.c
View file

@ -1,4 +1,4 @@
/* $Id: sd.c,v 1.9 2002/09/08 10:23:06 chorns Exp $
/* $Id: sd.c,v 1.10 2003/06/01 18:14:24 ekohl Exp $
*
* COPYRIGHT: See COPYING in the top level directory
* PROJECT: ReactOS kernel
@ -641,6 +641,7 @@ RtlSetSaclSecurityDescriptor(PSECURITY_DESCRIPTOR SecurityDescriptor,
return(STATUS_SUCCESS);
}
NTSTATUS STDCALL
RtlSelfRelativeToAbsoluteSD(PSECURITY_DESCRIPTOR RelSD,
PSECURITY_DESCRIPTOR AbsSD,
@ -654,7 +655,54 @@ RtlSelfRelativeToAbsoluteSD(PSECURITY_DESCRIPTOR RelSD,
PSID Group,
PDWORD GroupSize)
{
UNIMPLEMENTED;
ULONG TotalSize;
ULONG OwnerLength;
ULONG GroupLength;
ULONG DaclLength;
ULONG SaclLength;
PSID pOwner;
PSID pGroup;
PACL pDacl;
PACL pSacl;
if (!(RelSD->Control & SE_SELF_RELATIVE))
return STATUS_BAD_DESCRIPTOR_FORMAT;
RtlpQuerySecurityDescriptor (RelSD,
&pOwner,
&OwnerLength,
&pGroup,
&GroupLength,
&pDacl,
&DaclLength,
&pSacl,
&SaclLength);
if (OwnerLength > *OwnerSize ||
GroupLength > *GroupSize ||
DaclLength > *DaclSize ||
SaclLength > *SaclSize)
return STATUS_BUFFER_TOO_SMALL;
memmove (Owner, pOwner, OwnerLength);
memmove (Group, pGroup, GroupLength);
memmove (Dacl, pDacl, DaclLength);
memmove (Sacl, pSacl, SaclLength);
memmove (AbsSD, RelSD, sizeof (SECURITY_DESCRIPTOR));
AbsSD->Control &= ~SE_SELF_RELATIVE;
AbsSD->Owner = Owner;
AbsSD->Group = Group;
AbsSD->Dacl = Dacl;
AbsSD->Sacl = Sacl;
*OwnerSize = OwnerLength;
*GroupSize = GroupLength;
*DaclSize = DaclLength;
*SaclSize = SaclLength;
return STATUS_SUCCESS;
}
/* EOF */