/*** *varargs.h - XENIX style macros for variable argument functions * * Copyright (c) 1985-1994, 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] * ****/ #ifndef _INC_VARARGS #define _INC_VARARGS #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) \ ) \ ) \ ) #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 #endif /* _INC_VARARGS */