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/* |
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* Copyright (c) 1999-2006 Christophe Fillot. |
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* E-mail: cf@utc.fr |
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* |
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* mempool.c: Simple Memory Pools. |
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*/ |
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|
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#include <stdio.h> |
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#include <stdlib.h> |
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#include <string.h> |
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#include <stdarg.h> |
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#include <unistd.h> |
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#include <errno.h> |
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#include <signal.h> |
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#include <fcntl.h> |
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#include <ctype.h> |
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#include <time.h> |
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#include <sys/time.h> |
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#include <sys/stat.h> |
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#include <sys/types.h> |
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#include <assert.h> |
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|
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#include "utils.h" |
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#include "mempool.h" |
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|
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/* |
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* Internal function used to allocate a memory block, and do basic operations |
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* on it. It does not manipulate pools, so no mutex is needed. |
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*/ |
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static inline memblock_t *memblock_alloc(size_t size,int zeroed) |
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{ |
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memblock_t *block; |
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size_t total_size; |
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|
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total_size = size + sizeof(memblock_t); |
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if (!(block = malloc(total_size))) |
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return NULL; |
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|
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if (zeroed) |
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memset(block,0,total_size); |
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|
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block->tag = MEMBLOCK_TAG; |
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block->block_size = size; |
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block->prev = block->next = NULL; |
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return block; |
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} |
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|
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/* Insert block in linked list */ |
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static inline void memblock_insert(mempool_t *pool,memblock_t *block) |
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{ |
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MEMPOOL_LOCK(pool); |
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|
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pool->nr_blocks++; |
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pool->total_size += block->block_size; |
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|
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block->prev = NULL; |
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block->next = pool->block_list; |
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|
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if (block->next) |
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block->next->prev = block; |
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|
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pool->block_list = block; |
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|
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MEMPOOL_UNLOCK(pool); |
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} |
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|
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/* Remove block from linked list */ |
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static inline void memblock_delete(mempool_t *pool,memblock_t *block) |
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{ |
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MEMPOOL_LOCK(pool); |
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|
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pool->nr_blocks--; |
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pool->total_size -= block->block_size; |
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|
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if (!block->prev) |
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pool->block_list = block->next; |
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else |
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block->prev->next = block->next; |
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|
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if (block->next) |
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block->next->prev = block->prev; |
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|
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block->next = block->prev = NULL; |
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MEMPOOL_UNLOCK(pool); |
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} |
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|
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/* Allocate a new block in specified pool (internal function) */ |
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static inline void *mp_alloc_inline(mempool_t *pool,size_t size,int zeroed) |
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{ |
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memblock_t *block; |
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|
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if (!(block = memblock_alloc(size,zeroed))) |
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return NULL; |
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|
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block->pool = pool; |
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memblock_insert(pool,block); |
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return(block->data); |
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} |
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|
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/* Allocate a new block in specified pool */ |
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void *mp_alloc(mempool_t *pool,size_t size) |
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{ |
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return(mp_alloc_inline(pool,size,TRUE)); |
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} |
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|
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/* Allocate a new block which will not be zeroed */ |
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void *mp_alloc_n0(mempool_t *pool,size_t size) |
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{ |
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return(mp_alloc_inline(pool,size,FALSE)); |
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} |
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|
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/* Reallocate a block */ |
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void *mp_realloc(void *addr,size_t new_size) |
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{ |
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memblock_t *ptr,*block = (memblock_t *)addr - 1; |
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mempool_t *pool; |
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size_t total_size; |
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|
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assert(block->tag == MEMBLOCK_TAG); |
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pool = block->pool; |
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|
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/* remove this block from list */ |
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memblock_delete(pool,block); |
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|
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/* reallocate block with specified size */ |
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total_size = new_size + sizeof(memblock_t); |
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|
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if (!(ptr = realloc(block,total_size))) { |
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memblock_insert(pool,block); |
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return NULL; |
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} |
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|
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ptr->block_size = new_size; |
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memblock_insert(pool,ptr); |
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return ptr->data; |
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} |
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|
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/* Allocate a new memory block and copy data into it */ |
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void *mp_dup(mempool_t *pool,void *data,size_t size) |
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{ |
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void *p; |
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|
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if ((p = mp_alloc_n0(pool,size))) |
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memcpy(p,data,size); |
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|
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return p; |
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} |
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|
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/* Duplicate specified string and insert it in a memory pool */ |
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char *mp_strdup(mempool_t *pool,char *str) |
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{ |
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char *new_str; |
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|
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if ((new_str = mp_alloc(pool,strlen(str)+1)) == NULL) |
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return NULL; |
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|
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strcpy(new_str,str); |
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return new_str; |
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} |
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|
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/* Free block at specified address */ |
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int mp_free(void *addr) |
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{ |
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memblock_t *block = (memblock_t *)addr - 1; |
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mempool_t *pool; |
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|
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if (addr != NULL) { |
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assert(block->tag == MEMBLOCK_TAG); |
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pool = block->pool; |
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|
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memblock_delete(pool,block); |
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memset(block,0,sizeof(memblock_t)); |
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free(block); |
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} |
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|
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return(0); |
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} |
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|
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/* Free block at specified address and clean pointer */ |
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int mp_free_ptr(void *addr) |
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{ |
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void *p; |
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|
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assert(addr != NULL); |
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p = *(void **)addr; |
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*(void **)addr = NULL; |
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mp_free(p); |
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return(0); |
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} |
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|
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/* Free all blocks of specified pool */ |
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void mp_free_all_blocks(mempool_t *pool) |
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{ |
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memblock_t *block,*next; |
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|
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MEMPOOL_LOCK(pool); |
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|
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for(block=pool->block_list;block;block=next) { |
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next = block->next; |
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free(block); |
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} |
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|
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pool->block_list = NULL; |
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pool->nr_blocks = 0; |
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pool->total_size = 0; |
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|
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MEMPOOL_UNLOCK(pool); |
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} |
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|
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/* Free specified memory pool */ |
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void mp_free_pool(mempool_t *pool) |
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{ |
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mp_free_all_blocks(pool); |
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|
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if (!(pool->flags & MEMPOOL_FIXED)) |
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free(pool); |
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} |
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|
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/* Create a new pool in a fixed memory area */ |
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mempool_t *mp_create_fixed_pool(mempool_t *mp,char *name) |
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{ |
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memset(mp,0,sizeof(*mp)); |
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|
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if (pthread_mutex_init(&mp->lock,NULL) != 0) |
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return NULL; |
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|
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mp->name = name; |
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mp->block_list = NULL; |
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mp->flags = MEMPOOL_FIXED; |
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return mp; |
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} |
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|
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/* Create a new pool */ |
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mempool_t *mp_create_pool(char *name) |
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{ |
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mempool_t *mp = malloc(sizeof(*mp)); |
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|
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if (!mp || !mp_create_fixed_pool(mp,name)) { |
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free(mp); |
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return NULL; |
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} |
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|
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mp->flags = 0; /* clear "FIXED" flag */ |
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return mp; |
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} |