Sweden-Number/dlls/ntdll/large_int.c

422 lines
12 KiB
C
Raw Normal View History

/*
* Large integer functions
*
* Copyright 2000 Alexandre Julliard
* Copyright 2003 Thomas Mertes
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include "windef.h"
#include "winternl.h"
/*
* Note: we use LONGLONG instead of LARGE_INTEGER, because
* the latter is a structure and the calling convention for
* returning a structure would not be binary-compatible.
*
* FIXME: for platforms that don't have a native LONGLONG type,
* we should define LONGLONG as a structure similar to LARGE_INTEGER
* and do everything by hand. You are welcome to do it...
*/
/******************************************************************************
* RtlLargeIntegerAdd (NTDLL.@)
*/
LONGLONG WINAPI RtlLargeIntegerAdd( LONGLONG a, LONGLONG b )
{
return a + b;
}
/******************************************************************************
* RtlLargeIntegerSubtract (NTDLL.@)
*/
LONGLONG WINAPI RtlLargeIntegerSubtract( LONGLONG a, LONGLONG b )
{
return a - b;
}
/******************************************************************************
* RtlLargeIntegerNegate (NTDLL.@)
*/
LONGLONG WINAPI RtlLargeIntegerNegate( LONGLONG a )
{
return -a;
}
/******************************************************************************
* RtlLargeIntegerShiftLeft (NTDLL.@)
*/
LONGLONG WINAPI RtlLargeIntegerShiftLeft( LONGLONG a, INT count )
{
return a << count;
}
/******************************************************************************
* RtlLargeIntegerShiftRight (NTDLL.@)
*/
LONGLONG WINAPI RtlLargeIntegerShiftRight( LONGLONG a, INT count )
{
return (ULONGLONG)a >> count;
}
/******************************************************************************
* RtlLargeIntegerArithmeticShift (NTDLL.@)
*/
LONGLONG WINAPI RtlLargeIntegerArithmeticShift( LONGLONG a, INT count )
{
/* FIXME: gcc does arithmetic shift here, but it may not be true on all platforms */
return a >> count;
}
/******************************************************************************
* RtlLargeIntegerDivide (NTDLL.@)
*
* FIXME: should it be signed division instead?
*/
ULONGLONG WINAPI RtlLargeIntegerDivide( ULONGLONG a, ULONGLONG b, ULONGLONG *rem )
{
ULONGLONG ret = a / b;
if (rem) *rem = a - ret * b;
return ret;
}
/******************************************************************************
* RtlConvertLongToLargeInteger (NTDLL.@)
*/
LONGLONG WINAPI RtlConvertLongToLargeInteger( LONG a )
{
return a;
}
/******************************************************************************
* RtlConvertUlongToLargeInteger (NTDLL.@)
*/
ULONGLONG WINAPI RtlConvertUlongToLargeInteger( ULONG a )
{
return a;
}
/******************************************************************************
* RtlEnlargedIntegerMultiply (NTDLL.@)
*/
LONGLONG WINAPI RtlEnlargedIntegerMultiply( INT a, INT b )
{
return (LONGLONG)a * b;
}
/******************************************************************************
* RtlEnlargedUnsignedMultiply (NTDLL.@)
*/
ULONGLONG WINAPI RtlEnlargedUnsignedMultiply( UINT a, UINT b )
{
return (ULONGLONG)a * b;
}
/******************************************************************************
* RtlEnlargedUnsignedDivide (NTDLL.@)
*/
UINT WINAPI RtlEnlargedUnsignedDivide( ULONGLONG a, UINT b, UINT *remptr )
{
#if defined(__i386__) && defined(__GNUC__)
UINT ret, rem, p1, p2;
p1 = a >> 32;
p2 = a & 0xffffffffLL;
__asm__("div %4,%%eax"
: "=a" (ret), "=d" (rem)
: "0" (p2), "1" (p1), "g" (b) );
if (remptr) *remptr = rem;
return ret;
#else
UINT ret = a / b;
if (remptr) *remptr = a % b;
return ret;
#endif
}
/******************************************************************************
* RtlExtendedLargeIntegerDivide (NTDLL.@)
*/
LONGLONG WINAPI RtlExtendedLargeIntegerDivide( LONGLONG a, INT b, INT *rem )
{
LONGLONG ret = a / b;
if (rem) *rem = a - b * ret;
return ret;
}
/******************************************************************************
* RtlExtendedIntegerMultiply (NTDLL.@)
*/
LONGLONG WINAPI RtlExtendedIntegerMultiply( LONGLONG a, INT b )
{
return a * b;
}
/******************************************************************************
* RtlExtendedMagicDivide (NTDLL.@)
*
* Allows replacing a division by a longlong constant with a multiplication by
* the inverse constant.
*
* RETURNS
* (dividend * inverse_divisor) >> (64 + shift)
*
* NOTES
* If the divisor of a division is constant, the constants inverse_divisor and
* shift must be chosen such that inverse_divisor = 2^(64 + shift) / divisor.
* Then we have RtlExtendedMagicDivide(dividend,inverse_divisor,shift) ==
* dividend * inverse_divisor / 2^(64 + shift) == dividend / divisor.
*
* The Parameter inverse_divisor although defined as LONGLONG is used as
* ULONGLONG.
*/
#define LOWER_32(A) ((A) & 0xffffffff)
#define UPPER_32(A) ((A) >> 32)
LONGLONG WINAPI RtlExtendedMagicDivide(
LONGLONG dividend, /* [I] Dividend to be divided by the constant divisor */
LONGLONG inverse_divisor, /* [I] Constant computed manually as 2^(64+shift) / divisor */
INT shift) /* [I] Constant shift chosen to make inverse_divisor as big as possible for 64 bits */
{
ULONGLONG dividend_high;
ULONGLONG dividend_low;
ULONGLONG inverse_divisor_high;
ULONGLONG inverse_divisor_low;
ULONGLONG ah_bl;
ULONGLONG al_bh;
LONGLONG result;
int positive;
if (dividend < 0) {
dividend_high = UPPER_32((ULONGLONG) -dividend);
dividend_low = LOWER_32((ULONGLONG) -dividend);
positive = 0;
} else {
dividend_high = UPPER_32((ULONGLONG) dividend);
dividend_low = LOWER_32((ULONGLONG) dividend);
positive = 1;
} /* if */
inverse_divisor_high = UPPER_32((ULONGLONG) inverse_divisor);
inverse_divisor_low = LOWER_32((ULONGLONG) inverse_divisor);
ah_bl = dividend_high * inverse_divisor_low;
al_bh = dividend_low * inverse_divisor_high;
result = (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))) >> shift);
if (positive) {
return result;
} else {
return -result;
} /* if */
}
/******************************************************************************
* RtlLargeIntegerToChar [NTDLL.@]
*
* Convert an unsigned large integer to a character string.
*
* RETURNS
* Success: STATUS_SUCCESS. str contains the converted number
* Failure: STATUS_INVALID_PARAMETER, if base is not 0, 2, 8, 10 or 16.
* STATUS_BUFFER_OVERFLOW, if str would be larger than length.
* STATUS_ACCESS_VIOLATION, if str is NULL.
*
* NOTES
* Instead of base 0 it uses 10 as base.
* Writes at most length characters to the string str.
* Str is '\0' terminated when length allowes it.
* When str fits exactly in length characters the '\0' is ommitted.
* If value_ptr is NULL it crashes, as the native function does.
*
* DIFFERENCES
* - Accept base 0 as 10 instead of crashing as native function does.
* - The native function does produce garbage or STATUS_BUFFER_OVERFLOW for
* base 2, 8 and 16 when the value is larger than 0xFFFFFFFF.
*/
NTSTATUS WINAPI RtlLargeIntegerToChar(
const ULONGLONG *value_ptr, /* [I] Pointer to the value to be converted */
ULONG base, /* [I] Number base for conversion (allowed 0, 2, 8, 10 or 16) */
ULONG length, /* [I] Length of the str buffer in bytes */
PCHAR str) /* [O] Destination for the converted value */
{
ULONGLONG value = *value_ptr;
CHAR buffer[65];
PCHAR pos;
CHAR digit;
ULONG len;
if (base == 0) {
base = 10;
} else if (base != 2 && base != 8 && base != 10 && base != 16) {
return STATUS_INVALID_PARAMETER;
} /* if */
pos = &buffer[64];
*pos = '\0';
do {
pos--;
digit = value % base;
value = value / base;
if (digit < 10) {
*pos = '0' + digit;
} else {
*pos = 'A' + digit - 10;
} /* if */
} while (value != 0L);
len = &buffer[64] - pos;
if (len > length) {
return STATUS_BUFFER_OVERFLOW;
} else if (str == NULL) {
return STATUS_ACCESS_VIOLATION;
} else if (len == length) {
memcpy(str, pos, len);
} else {
memcpy(str, pos, len + 1);
} /* if */
return STATUS_SUCCESS;
}
/**************************************************************************
* RtlInt64ToUnicodeString (NTDLL.@)
*
* Convert a large unsigned integer to a '\0' terminated unicode string.
*
* RETURNS
* Success: STATUS_SUCCESS. str contains the converted number
* Failure: STATUS_INVALID_PARAMETER, if base is not 0, 2, 8, 10 or 16.
* STATUS_BUFFER_OVERFLOW, if str is too small to hold the string
* (with the '\0' termination). In this case str->Length
* is set to the length, the string would have (which can
* be larger than the MaximumLength).
*
* NOTES
* Instead of base 0 it uses 10 as base.
* If str is NULL it crashes, as the native function does.
*
* DIFFERENCES
* - Accept base 0 as 10 instead of crashing as native function does.
* - Do not return STATUS_BUFFER_OVERFLOW when the string is long enough.
* The native function does this when the string would be longer than 31
* characters even when the string parameter is long enough.
* - The native function does produce garbage or STATUS_BUFFER_OVERFLOW for
* base 2, 8 and 16 when the value is larger than 0xFFFFFFFF.
*/
NTSTATUS WINAPI RtlInt64ToUnicodeString(
ULONGLONG value, /* [I] Value to be converted */
ULONG base, /* [I] Number base for conversion (allowed 0, 2, 8, 10 or 16) */
UNICODE_STRING *str) /* [O] Destination for the converted value */
{
WCHAR buffer[65];
PWCHAR pos;
WCHAR digit;
if (base == 0) {
base = 10;
} else if (base != 2 && base != 8 && base != 10 && base != 16) {
return STATUS_INVALID_PARAMETER;
} /* if */
pos = &buffer[64];
*pos = '\0';
do {
pos--;
digit = value % base;
value = value / base;
if (digit < 10) {
*pos = '0' + digit;
} else {
*pos = 'A' + digit - 10;
} /* if */
} while (value != 0L);
str->Length = (&buffer[64] - pos) * sizeof(WCHAR);
if (str->Length >= str->MaximumLength) {
return STATUS_BUFFER_OVERFLOW;
} else {
memcpy(str->Buffer, pos, str->Length + sizeof(WCHAR));
} /* if */
return STATUS_SUCCESS;
}
/******************************************************************************
* _alldiv (NTDLL.@)
*/
LONGLONG WINAPI _alldiv( LONGLONG a, LONGLONG b )
{
return a / b;
}
/******************************************************************************
* _allmul (NTDLL.@)
*/
LONGLONG WINAPI _allmul( LONGLONG a, LONGLONG b )
{
return a * b;
}
/******************************************************************************
* _allrem (NTDLL.@)
*/
LONGLONG WINAPI _allrem( LONGLONG a, LONGLONG b )
{
return a % b;
}
/******************************************************************************
* _aulldiv (NTDLL.@)
*/
ULONGLONG WINAPI _aulldiv( ULONGLONG a, ULONGLONG b )
{
return a / b;
}
/******************************************************************************
* _aullrem (NTDLL.@)
*/
ULONGLONG WINAPI _aullrem( ULONGLONG a, ULONGLONG b )
{
return a % b;
}