mirror of
https://github.com/Unidata/netcdf-c.git
synced 2024-12-27 08:49:16 +08:00
85 lines
1.9 KiB
C
85 lines
1.9 KiB
C
/*
|
|
* Copyright 1997, University Corporation for Atmospheric Research
|
|
* See netcdf/COPYRIGHT file for copying and redistribution conditions.
|
|
*/
|
|
/* $Id: onstack.h,v 2.7 2006/09/15 20:40:39 ed Exp $ */
|
|
|
|
#ifndef _ONSTACK_H_
|
|
#define _ONSTACK_H_
|
|
/**
|
|
* This file provides definitions which allow us to
|
|
* "allocate" arrays on the stack where possible.
|
|
* (Where not possible, malloc and free are used.)
|
|
*
|
|
* The macro ALLOC_ONSTACK(name, type, nelems) is used to declare
|
|
* an array of 'type' named 'name' which is 'nelems' long.
|
|
* FREE_ONSTACK(name) is placed at the end of the scope of 'name'
|
|
* to call 'free' if necessary.
|
|
*
|
|
* The macro ALLOC_ONSTACK wraps a call to alloca() on most systems.
|
|
*/
|
|
|
|
#ifdef _WIN32
|
|
#ifdef HAVE_MALLOC_H
|
|
#undef HAVE_ALLOCA
|
|
#define HAVE_ALLOCA 1
|
|
#include <malloc.h>
|
|
#endif
|
|
#endif
|
|
|
|
#ifdef HAVE_ALLOCA
|
|
/*
|
|
* Implementation based on alloca()
|
|
*/
|
|
|
|
#if defined(__GNUC__)
|
|
# if !defined(alloca)
|
|
# define alloca __builtin_alloca
|
|
# endif
|
|
#else
|
|
# ifdef HAVE_ALLOCA_H
|
|
# include <alloca.h>
|
|
# elif defined(_AIX)
|
|
# pragma alloca
|
|
# endif /* HAVE_ALLOCA_H */
|
|
#endif /* __GNUC__ */
|
|
|
|
# if !defined(ALLOCA_ARG_T)
|
|
# define ALLOCA_ARG_T int /* the usual type of the alloca argument */
|
|
# endif
|
|
|
|
# define ALLOC_ONSTACK(name, type, nelems) \
|
|
type *const name = (type *) alloca((ALLOCA_ARG_T)((nelems) * sizeof(type)))
|
|
|
|
# define FREE_ONSTACK(name)
|
|
|
|
#elif defined(_CRAYC) && !defined(__crayx1) && !__cplusplus && __STDC__ > 1
|
|
/*
|
|
* Cray C allows sizing of arrays with non-constant values.
|
|
*/
|
|
|
|
# define ALLOC_ONSTACK(name, type, nelems) \
|
|
type name[nelems]
|
|
|
|
# define FREE_ONSTACK(name)
|
|
|
|
#elif defined(_WIN32) || defined(_WIN64)
|
|
#include <malloc.h>
|
|
#undef ALLOCA_ARG_T
|
|
# define ALLOCA_ARG_T size_t
|
|
|
|
#else
|
|
/*
|
|
* Default implementation. When all else fails, use malloc/free.
|
|
*/
|
|
|
|
# define ALLOC_ONSTACK(name, type, nelems) \
|
|
type *const name = (type *) malloc((nelems) * sizeof(type))
|
|
|
|
# define FREE_ONSTACK(name) \
|
|
free(name)
|
|
|
|
#endif
|
|
|
|
#endif /* _ONSTACK_H_ */
|