/*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
*
* Copyright 2021 Mike Becker, Olaf Wintermann 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.
*
* 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 mempool.h
* \brief Interface for memory pool implementations.
* \author Mike Becker
* \author Olaf Wintermann
* \copyright 2-Clause BSD License
*/
#ifndef UCX_MEMPOOL_H
#define UCX_MEMPOOL_H
#include "common.h"
#include "allocator.h"
#ifdef __cplusplus
extern "C" {
#endif
/** Internal structure for pooled memory. */
struct cx_mempool_memory_s;
/**
* The basic structure of a memory pool.
* Should be the first member of an actual memory pool implementation.
*/
struct cx_mempool_s {
/** The provided allocator. */
CxAllocator const *allocator;
/**
* A destructor that shall be automatically registered for newly allocated memory.
* This destructor MUST NOT free the memory.
*/
cx_destructor_func auto_destr;
/** Array of pooled memory. */
struct cx_mempool_memory_s **data;
/** Number of pooled memory items. */
size_t size;
/** Memory pool capacity. */
size_t capacity;
};
/**
* Common type for all memory pool implementations.
*/
typedef struct cx_mempool_s CxMempool;
/**
* Creates an array-based memory pool with a shared destructor function.
*
* This destructor MUST NOT free the memory.
*
* @param capacity the initial capacity of the pool
* @param destr the destructor function to use for allocated memory
* @return the created memory pool or \c NULL if allocation failed
*/
__attribute__((__warn_unused_result__))
CxMempool *cxMempoolCreate(size_t capacity, cx_destructor_func destr);
/**
* Creates a basic array-based memory pool.
*
* @param capacity the initial capacity of the pool
* @return the created memory pool or \c NULL if allocation failed
*/
__attribute__((__warn_unused_result__))
static inline CxMempool *cxBasicMempoolCreate(size_t capacity) {
return cxMempoolCreate(capacity, NULL);
}
/**
* Destroys a memory pool and frees the managed memory.
*
* @param pool the memory pool to destroy
*/
__attribute__((__nonnull__))
void cxMempoolDestroy(CxMempool *pool);
/**
* Sets the destructor function for a specific allocated memory object.
*
* If the memory is not managed by a UCX memory pool, the behavior is undefined.
* The destructor MUST NOT free the memory.
*
* @param memory the object allocated in the pool
* @param fnc the destructor function
*/
__attribute__((__nonnull__))
void cxMempoolSetDestructor(
void *memory,
cx_destructor_func fnc
);
/**
* Registers foreign memory with this pool.
*
* The destructor, in contrast to memory allocated by the pool, MUST free the memory.
*
* A small portion of memory will be allocated to register the information in the pool.
* If that allocation fails, this function will return non-zero.
*
* @param pool the pool
* @param memory the object allocated in the pool
* @param destr the destructor function
* @return zero on success, non-zero on failure
*/
__attribute__((__nonnull__))
int cxMempoolRegister(
CxMempool *pool,
void *memory,
cx_destructor_func destr
);
#ifdef __cplusplus
} // extern "C"
#endif
#endif // UCX_MEMPOOL_H