HugeAllocator.hxx

/*
 * Copyright (C) 2003-2014 The Music Player Daemon Project
 * http://www.musicpd.org
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#ifndef MPD_HUGE_ALLOCATOR_HXX
#define MPD_HUGE_ALLOCATOR_HXX

#include "Compiler.h"

#include <stddef.h>

#ifdef __linux__

/**
 * Allocate a huge amount of memory.  This will be done in a way that
 * allows giving the memory back to the kernel as soon as we don't
 * need it anymore.  On the downside, this call is expensive.
 */
gcc_malloc
void *
HugeAllocate(size_t size);

/**
 * @param p an allocation returned by HugeAllocate()
 * @param size the allocation's size as passed to HugeAllocate()
 */
void
HugeFree(void *p, size_t size);

/**
 * Discard any data stored in the allocation and give the memory back
 * to the kernel.  After returning, the allocation still exists and
 * can be reused at any time, but its contents are undefined.
 *
 * @param p an allocation returned by HugeAllocate()
 * @param size the allocation's size as passed to HugeAllocate()
 */
void
HugeDiscard(void *p, size_t size);

#else

/* not Linux: fall back to standard C calls */

#include <stdlib.h>

gcc_malloc
static inline void *
HugeAllocate(size_t size)
{
	return malloc(size);
}

static inline void
HugeFree(void *p, size_t)
{
	free(p);
}

static inline void
HugeDiscard(void *, size_t)
{
}

#endif

#endif