NT4/public/sdk/inc/crt/varargs.h
2020-09-30 17:12:29 +02:00

164 lines
4.4 KiB
C

/***
*varargs.h - XENIX style macros for variable argument functions
*
* Copyright (c) 1985-1995, Microsoft Corporation. All rights reserved.
*
*Purpose:
* This file defines XENIX style macros for accessing arguments of a
* function which takes a variable number of arguments.
* [System V]
*
* [Public]
*
****/
#if _MSC_VER > 1000
#pragma once
#endif
#ifndef _INC_VARARGS
#define _INC_VARARGS
#if !defined(_WIN32) && !defined(_MAC)
#error ERROR: Only Mac or Win32 targets supported!
#endif
#ifdef _MSC_VER
/*
* Currently, all MS C compilers for Win32 platforms default to 8 byte
* alignment.
*/
#pragma pack(push,8)
#endif /* _MSC_VER */
#ifdef __cplusplus
extern "C" {
#endif
#if __STDC__
#error varargs.h incompatible with ANSI (use stdarg.h)
#endif
#ifndef _VA_LIST_DEFINED
#ifdef _M_ALPHA
typedef struct {
char *a0; /* pointer to first homed integer argument */
int offset; /* byte offset of next parameter */
} va_list;
#else
typedef char *va_list;
#endif
#define _VA_LIST_DEFINED
#endif
#if defined(_M_IX86)
/*
* define a macro to compute the size of a type, variable or expression,
* rounded up to the nearest multiple of sizeof(int). This number is its
* size as function argument (Intel architecture). Note that the macro
* depends on sizeof(int) being a power of 2!
*/
#define _INTSIZEOF(n) ( (sizeof(n) + sizeof(int) - 1) & ~(sizeof(int) - 1) )
#define va_dcl va_list va_alist;
#define va_start(ap) ap = (va_list)&va_alist
#define va_arg(ap,t) ( *(t *)((ap += _INTSIZEOF(t)) - _INTSIZEOF(t)) )
#define va_end(ap) ap = (va_list)0
#elif defined(_M_MRX000) /* _MIPS_ */
#define va_dcl int va_alist;
#define va_start(list) list = (char *) &va_alist
#define va_end(list)
#define va_arg(list, mode) ((mode *)(list =\
(char *) ((((int)list + (__builtin_alignof(mode)<=4?3:7)) &\
(__builtin_alignof(mode)<=4?-4:-8))+sizeof(mode))))[-1]
/* +++++++++++++++++++++++++++++++++++++++++++
Because of parameter passing conventions in C:
use mode=int for char, and short types
use mode=double for float types
use a pointer for array types
+++++++++++++++++++++++++++++++++++++++++++ */
#elif defined(_M_ALPHA)
/*
* The Alpha compiler supports two builtin functions that are used to
* implement stdarg/varargs. The __builtin_va_start function is used
* by va_start to initialize the data structure that locates the next
* argument. The __builtin_isfloat function is used by va_arg to pick
* which part of the home area a given register argument is stored in.
* The home area is where up to six integer and/or six floating point
* register arguments are stored down (so they can also be referenced
* by a pointer like any arguments passed on the stack).
*/
extern void * __builtin_va_start(va_list, ...);
#define va_dcl long va_alist;
#define va_start(list) __builtin_va_start(list, va_alist, 0)
#define va_end(list)
#define va_arg(list, mode) \
( *( ((list).offset += ((int)sizeof(mode) + 7) & -8) , \
(mode *)((list).a0 + (list).offset - \
((__builtin_isfloat(mode) && (list).offset <= (6 * 8)) ? \
(6 * 8) + 8 : ((int)sizeof(mode) + 7) & -8) \
) \
) \
)
#elif defined(_M_PPC)
/*
* define a macro to compute the size of a type, variable or expression,
* rounded up to the nearest multiple of sizeof(int). This number is its
* size as function argument (PPC architecture). Note that the macro
* depends on sizeof(int) being a power of 2!
*/
/* this is for LITTLE-ENDIAN PowerPC */
/* bytes that a type occupies in the argument list */
#define _INTSIZEOF(n) ( (sizeof(n) + sizeof(int) - 1) & ~(sizeof(int) - 1) )
/* return 'ap' adjusted for type 't' in arglist */
#define _ALIGNIT(ap,t) \
((((int)(ap))+(sizeof(t)<8?3:7)) & (sizeof(t)<8?~3:~7))
#define va_dcl va_list va_alist;
#define va_start(ap) ap = (va_list)&va_alist
#define va_arg(ap,t) ( *(t *)((ap = (char *) (_ALIGNIT(ap, t) + _INTSIZEOF(t))) - _INTSIZEOF(t)) )
#define va_end(ap) ap = (va_list)0
#else
/* A guess at the proper definitions for other platforms */
#define _INTSIZEOF(n) ( (sizeof(n) + sizeof(int) - 1) & ~(sizeof(int) - 1) )
#define va_dcl va_list va_alist;
#define va_start(ap) ap = (va_list)&va_alist
#define va_arg(ap,t) ( *(t *)((ap += _INTSIZEOF(t)) - _INTSIZEOF(t)) )
#define va_end(ap) ap = (va_list)0
#endif
#ifdef __cplusplus
}
#endif
#ifdef _MSC_VER
#pragma pack(pop)
#endif /* _MSC_VER */
#endif /* _INC_VARARGS */