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/*
* Copyright (c) 1996-1999 University of Utah and the Flux Group.
* All rights reserved.
*
* This file is part of the Flux OSKit. The OSKit is free software, also known
* as "open source;" you can redistribute it and/or modify it under the terms
* of the GNU General Public License (GPL), version 2, as published by the Free
* Software Foundation (FSF). To explore alternate licensing terms, contact
* the University of Utah at csl-dist@cs.utah.edu or +1-801-585-3271.
*
* The OSKit 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 GPL for more details. You should have
* received a copy of the GPL along with the OSKit; see the file COPYING. If
* not, write to the FSF, 59 Temple Place #330, Boston, MA 02111-1307, USA.
*/
/*
* Implemement memdebug_free()
*/
#include <assert.h>
#include <string.h>
#include <oskit/lmm.h>
#include "memdebug.h"
/*
* memdebug_free()
*
* returns -1 if there was an error. 0 otherwise.
*/
int
memdebug_free(void* mem, int wipeval, char caller, int blocksize, char *file, int line)
{
memdebug_mhead *head;
memdebug_mtail *tail;
int rc;
#if ALLOW_MORALLY_QUESTIONABLE_PRACTICE
/* free(NULL) is technically legal. */
if (!mem) return 0;
#else
if (!mem)
{
memdebug_info_dump("MEMDEBUG BOGOSITY: Tried to free(NULL) at",
file, line);
return -1;
}
#endif
head = (memdebug_mhead*)mem - 1;
tail = (memdebug_mtail*)((void*)(head + 1) + head->size);
/*
* Do the "already free" check here, as the memdebug_ptrchk() message
* isn't appropriate.
*/
if (head->magic == FREE_MAGIC)
{
memdebug_info_dump("MEMDEBUG BOGOSITY: Block has already been free()'d; detected at",
file, line);
memdebug_bogosity(head);
}
/*
* Do the standard set of sanity checks on the raw memory pointer.
*/
rc = memdebug_traced_ptrchk(mem, file, line);
if (rc)
{
memdebug_printf("--Detected during free()\n");
#if 0
/*
* enable this if you want a trace of the stack at the
* point where the free is called
*/
dump_stack_trace_bis(memdebug_printf, 20);
#endif
/* Only bail on really bad errors */
if (rc == -1)
return -1;
}
DPRINTF("Doing free()-specific checks.\n");
/*
* Make sure the user isn't smalloc()'ing and free()'ing or
* vice-versa.
*/
if ((caller == SMALLOC_CALLER) &&
(!(head->flags & SMALLOC_CREATED)))
{
memdebug_printf("MEMDEBUG BOGOSITY:"
" sfree() of block allocated by malloc() ");
memdebug_info_dump("at", file, line);
memdebug_bogosity(head);
/* Don't return, we can continue and do the correct thing. */
}
else if ((caller == MALLOC_CALLER)
&& (head->flags & SMALLOC_CREATED))
{
memdebug_printf("MEMDEBUG BOGOSITY:"
" free() of block allocated by smalloc() ");
memdebug_info_dump("at", file, line);
memdebug_bogosity(head);
/* Don't return, we can continue and do the correct thing. */
}
/*
* If this is an sfree() call, then check to make sure the
* user is passing in the correct size.
*/
if ((blocksize != -1) && (blocksize != head->size))
{
memdebug_printf("MEMDEBUG BOGOSITY:"
" sfree()'ing a block with incorrect size, %d (should be %u) ",
blocksize, head->size);
memdebug_info_dump("at", file, line);
memdebug_bogosity(head);
/* Don't return, we can continue and do the correct thing. */
}
/* Remove the block from the allocated list. Keep thread-safe.*/
mem_lock();
head->next->prev = head->prev;
head->prev->next = head->next;
mem_unlock();
/* Mark the block freed. */
head->magic = FREE_MAGIC;
tail->magic = FREE_MAGIC;
/*
* Fill the freed block with bogus data to reveal reads from
* freed memory blocks.
*/
memset(mem, wipeval, head->size);
/* Free it. */
memdebug_untraced_free(head,
head->size + sizeof(memdebug_mhead) +
sizeof(memdebug_mtail));
DPRINTF("finished.\n");
return 0;
}
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