windows-nt/Source/XPSP1/NT/multimedia/media/avi/mciwnd.16/muldiv32.h
2020-09-26 16:20:57 +08:00

59 lines
1.7 KiB
C

//==========================================================================;
//
// THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY
// KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A PARTICULAR
// PURPOSE.
//
// Copyright (c) 1993, 1994 Microsoft Corporation. All Rights Reserved.
//
//--------------------------------------------------------------------------;
//
// muldiv32.h
//
// Description: math routines for 32 bit signed and unsiged numbers.
//
// MulDiv32(a,b,c) = (a * b) / c (round down, signed)
//
// MulDivRD(a,b,c) = (a * b) / c (round down, unsigned)
// MulDivRN(a,b,c) = (a * b + c/2) / c (round nearest, unsigned)
// MulDivRU(a,b,c) = (a * b + c-1) / c (round up, unsigned)
//
// Description:
//
// History:
// 9/21/93 cjp [curtisp]
// 9/23/93 stl [toddla]
//
//==========================================================================;
#ifndef _INC_MULDIV32
#define _INC_MULDIV32
#ifdef __cplusplus
extern "C"
{
#endif
extern LONG FAR PASCAL MulDiv32(LONG a,LONG b,LONG c);
extern DWORD FAR PASCAL MulDivRN(DWORD a,DWORD b,DWORD c);
extern DWORD FAR PASCAL MulDivRD(DWORD a,DWORD b,DWORD c);
extern DWORD FAR PASCAL MulDivRU(DWORD a,DWORD b,DWORD c);
#if defined(WIN32) || defined(_WIN32)
// GDI32s MulDiv is the same as MulDivRN
#define MulDivRN(a,b,c) (DWORD)MulDiv((LONG)(a),(LONG)(b),(LONG)(c))
#endif
//
// some code references these by other names.
//
#define muldiv32 MulDivRN
#define muldivrd32 MulDivRD
#define muldivru32 MulDivRU
#ifdef __cplusplus
}
#endif
#endif // _INC_MULDIV32