/* mpool.c memory pool management
*
* Copyright (c) 1994-2008 Carnegie Mellon University. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. 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.
*
* 3. The name "Carnegie Mellon University" must not be used to
* endorse or promote products derived from this software without
* prior written permission. For permission or any legal
* details, please contact
* Carnegie Mellon University
* Center for Technology Transfer and Enterprise Creation
* 4615 Forbes Avenue
* Suite 302
* Pittsburgh, PA 15213
* (412) 268-7393, fax: (412) 268-7395
* innovation@andrew.cmu.edu
*
* 4. Redistributions of any form whatsoever must retain the following
* acknowledgment:
* "This product includes software developed by Computing Services
* at Carnegie Mellon University (http://www.cmu.edu/computing/)."
*
* CARNEGIE MELLON UNIVERSITY DISCLAIMS ALL WARRANTIES WITH REGARD TO
* THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS, IN NO EVENT SHALL CARNEGIE MELLON UNIVERSITY BE LIABLE
* FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
* AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
* OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include <config.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <stdio.h>
#include <string.h>
#include <signal.h>
#include <stdlib.h>
#include "mpool.h"
#include "xmalloc.h"
#include "exitcodes.h"
struct mpool
{
struct mpool_blob *blob;
};
struct mpool_blob
{
size_t size;
unsigned char *base; /* Base of allocated section */
unsigned char *ptr; /* End of allocated section */
struct mpool_blob *next; /* Next Pool */
};
static struct mpool_blob *new_mpool_blob(size_t size)
{
struct mpool_blob *blob = xmalloc(sizeof(struct mpool_blob));
if(!size) size = DEFAULT_MPOOL_SIZE;
blob->base = blob->ptr = xmalloc(size);
blob->size = size;
blob->next = NULL;
return blob;
}
/* Create a new pool */
EXPORTED struct mpool *new_mpool(size_t size)
{
struct mpool *ret = xmalloc(sizeof(struct mpool));
ret->blob = new_mpool_blob(size);
return ret;
}
/* Free a pool */
EXPORTED void free_mpool(struct mpool *pool)
{
struct mpool_blob *p, *p_next;
if (!pool) return;
if (!pool->blob) {
fatal("memory pool without a blob", EC_TEMPFAIL);
return;
}
p = pool->blob;
while(p) {
p_next = p->next;
free(p->base);
free(p);
p = p_next;
}
free(pool);
}
#ifdef ROUNDUP
#undef ROUNDUP
#endif
/* round up to the next multiple of 16 bytes if necessary */
/* 0xFF...FFF0 = ~0 ^ 0xF */
#define ROUNDUP(num) (((num) + 15) & (~((unsigned long) 0x0) ^ 0xF))
/* Allocate from a pool */
EXPORTED void *mpool_malloc(struct mpool *pool, size_t size)
{
void *ret = NULL;
struct mpool_blob *p;
size_t remain;
if(!pool || !pool->blob) {
fatal("mpool_malloc called without a valid pool", EC_TEMPFAIL);
}
if(!size) {
/* This is legal under ANSI C, so we should allow it too */
size = 1;
}
p = pool->blob;
/* This is a bit tricky, not only do we have to make sure that the current
* pool has enough room, we need to be sure that we haven't rounded p->ptr
* outside of the current pool anyway */
remain = p->size - ((char *)p->ptr - (char *)p->base);
if (remain < size ||
(char *) p->ptr > (p->size + (char *) p->base)) {
/* Need a new pool */
struct mpool_blob *new_pool;
size_t new_pool_size = 2 * ((size > p->size) ? size : p->size);
new_pool = new_mpool_blob(new_pool_size);
new_pool->next = p;
p = pool->blob = new_pool;
}
ret = p->ptr;
/* make sure that the next thing we allocate is align on
a ROUNDUP boundary */
p->ptr = p->base + ROUNDUP(p->ptr - p->base + size);
return ret;
}
EXPORTED char *mpool_strndup(struct mpool *pool, const char *str, size_t n)
{
char *ret;
if(!str) return NULL;
ret = mpool_malloc(pool, n+1);
strncpy(ret, str, n);
ret[n] = '\0';
return ret;
}
EXPORTED char *mpool_strdup(struct mpool *pool, const char *str)
{
size_t len;
if(!str) return NULL;
len = strlen(str);
return mpool_strndup(pool, str, len);
}