/*
* regional.c -- region based memory allocator.
*
* Copyright (c) 2001-2006, NLnet Labs. All rights reserved.
*
* Copyright (c) 2007, NLnet Labs. All rights reserved.
*
* This software is open source.
*
* 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 NLNET LABS 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 COPYRIGHT
* HOLDER 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.
*/
/**
* \file
* Regional allocator. Allocates small portions of of larger chunks.
*/
#include "config.h"
#include "util/log.h"
#include "util/regional.h"
#ifdef ALIGNMENT
# undef ALIGNMENT
#endif
/** increase size until it fits alignment of s bytes */
#define ALIGN_UP(x, s) (((x) + s - 1) & (~(s - 1)))
/** what size to align on; make sure a char* fits in it. */
#define ALIGNMENT (sizeof(uint64_t))
/** Default reasonable size for chunks */
#define REGIONAL_CHUNK_SIZE 8192
#ifdef UNBOUND_ALLOC_NONREGIONAL
/** All objects allocated outside of chunks, for debug */
#define REGIONAL_LARGE_OBJECT_SIZE 0
#else
/** Default size for large objects - allocated outside of chunks. */
#define REGIONAL_LARGE_OBJECT_SIZE 2048
#endif
struct regional*
regional_create(void)
{
return regional_create_custom(REGIONAL_CHUNK_SIZE);
}
/** init regional struct with first block */
static void
regional_init(struct regional* r)
{
size_t a = ALIGN_UP(sizeof(struct regional), ALIGNMENT);
r->data = (char*)r + a;
r->available = r->first_size - a;
r->next = NULL;
r->large_list = NULL;
r->total_large = 0;
}
struct regional*
regional_create_custom(size_t size)
{
struct regional* r = (struct regional*)malloc(size);
log_assert(sizeof(struct regional) <= size);
if(!r) return NULL;
r->first_size = size;
regional_init(r);
return r;
}
void
regional_free_all(struct regional *r)
{
char* p = r->next, *np;
while(p) {
np = *(char**)p;
free(p);
p = np;
}
p = r->large_list;
while(p) {
np = *(char**)p;
free(p);
p = np;
}
regional_init(r);
}
void
regional_destroy(struct regional *r)
{
if(!r) return;
regional_free_all(r);
free(r);
}
void *
regional_alloc(struct regional *r, size_t size)
{
size_t a = ALIGN_UP(size, ALIGNMENT);
void *s;
/* large objects */
if(a > REGIONAL_LARGE_OBJECT_SIZE) {
s = malloc(ALIGNMENT + size);
if(!s) return NULL;
r->total_large += ALIGNMENT+size;
*(char**)s = r->large_list;
r->large_list = (char*)s;
return (char*)s+ALIGNMENT;
}
/* create a new chunk */
if(a > r->available) {
s = malloc(REGIONAL_CHUNK_SIZE);
if(!s) return NULL;
*(char**)s = r->next;
r->next = (char*)s;
r->data = (char*)s + ALIGNMENT;
r->available = REGIONAL_CHUNK_SIZE - ALIGNMENT;
}
/* put in this chunk */
r->available -= a;
s = r->data;
r->data += a;
return s;
}
void *
regional_alloc_init(struct regional* r, const void *init, size_t size)
{
void *s = regional_alloc(r, size);
if(!s) return NULL;
memcpy(s, init, size);
return s;
}
void *
regional_alloc_zero(struct regional *r, size_t size)
{
void *s = regional_alloc(r, size);
if(!s) return NULL;
memset(s, 0, size);
return s;
}
char *
regional_strdup(struct regional *r, const char *string)
{
return (char*)regional_alloc_init(r, string, strlen(string)+1);
}
/**
* reasonably slow, but stats and get_mem are not supposed to be fast
* count the number of chunks in use
*/
static size_t
count_chunks(struct regional* r)
{
size_t c = 1;
char* p = r->next;
while(p) {
c++;
p = *(char**)p;
}
return c;
}
/**
* also reasonably slow, counts the number of large objects
*/
static size_t
count_large(struct regional* r)
{
size_t c = 0;
char* p = r->large_list;
while(p) {
c++;
p = *(char**)p;
}
return c;
}
void
regional_log_stats(struct regional *r)
{
/* some basic assertions put here (non time critical code) */
log_assert(ALIGNMENT >= sizeof(char*));
log_assert(REGIONAL_CHUNK_SIZE > ALIGNMENT);
log_assert(REGIONAL_CHUNK_SIZE-ALIGNMENT > REGIONAL_LARGE_OBJECT_SIZE);
log_assert(REGIONAL_CHUNK_SIZE >= sizeof(struct regional));
/* debug print */
log_info("regional %u chunks, %u large",
(unsigned)count_chunks(r), (unsigned)count_large(r));
}
size_t
regional_get_mem(struct regional* r)
{
return r->first_size + (count_chunks(r)-1)*REGIONAL_CHUNK_SIZE
+ r->total_large;
}
