gecko-dev/cmd/winfe/cast.h
1998-03-28 02:44:41 +00:00

139 lines
3.7 KiB
C

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*-
*
* The contents of this file are subject to the Netscape Public License
* Version 1.0 (the "NPL"); you may not use this file except in
* compliance with the NPL. You may obtain a copy of the NPL at
* http://www.mozilla.org/NPL/
*
* Software distributed under the NPL is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the NPL
* for the specific language governing rights and limitations under the
* NPL.
*
* The Initial Developer of this code under the NPL is Netscape
* Communications Corporation. Portions created by Netscape are
* Copyright (C) 1998 Netscape Communications Corporation. All Rights
* Reserved.
*/
#ifndef __CAST_H
#define __CAST_H
// To handle casts between the various windows
// platforms.
// We use these macros/inline functions instead of just
// casting directly so that we can manipulate their
// behaviour on a broad scale, and very customized
// behaviour can be achieved if you need to range
// check values in debug mode, etc.
// PAY ATTENTION, OR WE'RE ALL DEAD:
// The use of inline functions is to avoid the over evaluation
// problem (common to macros) when repeating parameters
// in doing a computation.
// i.e.
// #define EVAL(a) ((a) + (a))
//
// EVAL(a *= a + a);
// However, by using inline function, it is not possible
// to provide every possible cast operation that macros
// do cover. This is a known shortfall. Templates were
// the solution, but it's not clear that we'll ever have
// a 16 bit compiler which supports templates. You will
// have to implement each needed cast seperately. You
// can mostly avoid the problem by using the largest possible
// data type.
// To turn off all casting in the front end which
// utilizes these macros, define NO_CAST, and get
// ready for a boatload of warnings.
//#define NO_CAST
// Now onto the show.
// GAB 09-13-95
// Native integer cast, good for use in WinAPI calls.
// In debug, we camp on you if we actually lose bits, as it
// is ambiguous if we should hold the top limit to MAXINT
// or if we should just take the lower sizeof(int) bytes
// and ignore the rest.
#ifndef NO_CAST
#ifndef _DEBUG
#define CASTINT(a) ((int)(a))
#else
inline int CASTINT(long a) {
int b = (int)a;
ASSERT(a == (long)b);
return(b);
}
#endif
#else
#define CASTINT(a) (a)
#endif
// Native unsigned cast.
// In debug, we camp on you if we actually lose bits.
#ifndef NO_CAST
#ifndef _DEBUG
#define CASTUINT(a) ((unsigned)(a))
#else
inline unsigned CASTUINT(long a) {
unsigned b = (unsigned)a;
ASSERT(a == (long)b);
return(b);
}
#endif
#else
#define CASTUINT(a) (a)
#endif
#ifndef NO_CAST
#ifndef _DEBUG
#define CASTSIZE_T(a) ((size_t)(a))
#else
inline size_t CASTSIZE_T(long a) {
size_t b = (size_t)a;
ASSERT(a == (long)b);
return(b);
}
#endif
#else
#define CASTSIZE_T(a) (a)
#endif
#ifndef NO_CAST
#ifndef _DEBUG
#define CASTDWORD(a) ((DWORD)(a))
#else
inline DWORD CASTDWORD(long a) {
DWORD b = (DWORD)a;
ASSERT(a == (long)b);
return(b);
}
#endif
#else
#define CASTDWORD(a) (a)
#endif
// NCAPI data from URL_Struct
#define NCAPIDATA(pUrl) ((CNcapiUrlData *)(pUrl)->ncapi_data)
// Context casts
#define CX2VOID(pContext, CastFromClassCX) ((void *)((CAbstractCX *)((CastFromClassCX *)(pContext))))
#define VOID2CX(pVoid, CastToClassCX) ((CastToClassCX *)((CAbstractCX *)((void *)(pVoid))))
#define ABSTRACTCX(pXPCX) ((pXPCX)->fe.cx)
#define BOOKMARKCX(pXPCX) ((CNewBookmarkWnd *)((pXPCX)->fe.cx))
#define WINCX(pXPCX) ((CWinCX *)((pXPCX)->fe.cx))
#define CXDC(pXPCX) ((CDCCX *)((pXPCX)->fe.cx))
#define PANECX(pXPCX) ((CPaneCX *)((pXPCX)->fe.cx))
#endif // __CAST_H