ref: c6bc9714dd9e3ba1e022327f607ea09c40440d3d
dir: /include/internal/stack_alloc.h/
/* Copyright (C) 2002 Jean-Marc Valin */
/**
@file stack_alloc.h
@brief Temporary memory allocation on stack
*/
/*
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
- Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
- Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
- Neither the name of the Xiph.org Foundation nor the names of its
contributors may be used to endorse or promote products derived from
this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR
CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef STACK_ALLOC_H
#define STACK_ALLOC_H
#ifdef WIN32
#include <malloc.h>
#else
#ifdef HAVE_ALLOCA_H
#include <alloca.h>
#else
#include <stdlib.h>
#endif
#endif
/**
* @def ALIGN(stack, size)
*
* Aligns the stack to a 'size' boundary
*
* @param stack Stack
* @param size New size boundary
*/
/**
* @def PUSH(stack, size, type)
*
* Allocates 'size' elements of type 'type' on the stack
*
* @param stack Stack
* @param size Number of elements
* @param type Type of element
*/
/**
* @def VARDECL(var)
*
* Declare variable on stack
*
* @param var Variable to declare
*/
/**
* @def ALLOC(var, size, type)
*
* Allocate 'size' elements of 'type' on stack
*
* @param var Name of variable to allocate
* @param size Number of elements
* @param type Type of element
*/
#ifdef ENABLE_VALGRIND
#include <valgrind/memcheck.h>
#define ALIGN(stack, size) ((stack) += ((size) - (long)(stack)) & ((size)-1))
#define PUSH(stack, size, type) \
(VALGRIND_MAKE_NOACCESS(stack, 1000), ALIGN((stack), sizeof(type)), \
VALGRIND_MAKE_WRITABLE(stack, ((size) * sizeof(type))), \
(stack) += ((size) * sizeof(type)), \
(type *)((stack) - ((size) * sizeof(type))))
#else
#define ALIGN(stack, size) ((stack) += ((size) - (long)(stack)) & ((size)-1))
#define PUSH(stack, size, type) \
(ALIGN((stack), sizeof(type)), (stack) += ((size) * sizeof(type)), \
(type *)((stack) - ((size) * sizeof(type))))
#endif
#if defined(VAR_ARRAYS)
#define VARDECL(var)
#define ALLOC(var, size, type) type var[size]
#elif defined(USE_ALLOCA)
#define VARDECL(var) var
#define ALLOC(var, size, type) var = alloca(sizeof(type) * (size))
#else
#define VARDECL(var) var
#define ALLOC(var, size, type) var = PUSH(stack, size, type)
#endif
#endif