strongswan/src/libstrongswan/utils/utils/align.c

63 lines
1.4 KiB
C

/*
* Copyright (C) 2008-2014 Tobias Brunner
* Copyright (C) 2005-2008 Martin Willi
* HSR Hochschule fuer Technik Rapperswil
*
* 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. See <http://www.fsf.org/copyleft/gpl.txt>.
*
* 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.
*/
#include <utils/utils.h>
#include <utils/debug.h>
/**
* Described in header.
*/
void* malloc_align(size_t size, uint8_t align)
{
uint8_t pad;
void *ptr;
if (align == 0)
{
align = 1;
}
ptr = malloc(align + sizeof(pad) + size);
if (!ptr)
{
return NULL;
}
/* store padding length just before data, down to the allocation boundary
* to do some verification during free_align() */
pad = align - ((uintptr_t)ptr % align);
memset(ptr, pad, pad);
return ptr + pad;
}
/**
* Described in header.
*/
void free_align(void *ptr)
{
uint8_t pad, *pos;
pos = ptr - 1;
/* verify padding to check any corruption */
for (pad = *pos; (void*)pos >= ptr - pad; pos--)
{
if (*pos != pad)
{
DBG1(DBG_LIB, "!!!! invalid free_align() !!!!");
return;
}
}
free(ptr - pad);
}