/**
* Copyright (C) 2008 Happy Fish / YuQing
*
* FastDFS may be copied only under the terms of the GNU General
* Public License V3, which may be found in the FastDFS source kit.
* Please visit the FastDFS Home Page http://www.csource.org/ for more detail.
**/

//fast_mblock.h

#ifndef _FAST_MBLOCK_H
#define _FAST_MBLOCK_H

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <pthread.h>
#include "common_define.h"
#include "chain.h"

/* free node chain */ 
struct fast_mblock_node
{
	struct fast_mblock_node *next;
    int recycle_timestamp;
	char data[0];   //the data buffer
};

/* malloc chain */
struct fast_mblock_malloc
{
	struct fast_mblock_malloc *next;
};

struct fast_mblock_chain {
	struct fast_mblock_node *head;
	struct fast_mblock_node *tail;
};

typedef int (*fast_mblock_alloc_init_func)(void *element);

struct fast_mblock_man
{
	struct fast_mblock_node *free_chain_head;    //free node chain
    struct fast_mblock_chain delay_free_chain;   //delay free node chain
	struct fast_mblock_malloc *malloc_chain_head; //malloc chain to be freed
    fast_mblock_alloc_init_func alloc_init_func;
	int element_size;         //element size
	int alloc_elements_once;  //alloc elements once
    int total_count;          //total element count
    bool need_lock;
	pthread_mutex_t lock;     //the lock for read / write free node chain
};

#define fast_mblock_to_node_ptr(data_ptr) \
        (struct fast_mblock_node *)((char *)data_ptr - ((size_t)(char *) \
                    &((struct fast_mblock_node *)0)->data))

#ifdef __cplusplus
extern "C" {
#endif

#define fast_mblock_init(mblock, element_size, alloc_elements_once) \
    fast_mblock_init_ex(mblock, element_size, alloc_elements_once, NULL, true)

/**
mblock init
parameters:
	mblock: the mblock pointer
	element_size: element size, such as sizeof(struct xxx)
	alloc_elements_once: malloc elements once, 0 for malloc 1MB memory once
return error no, 0 for success, != 0 fail
*/
int fast_mblock_init_ex(struct fast_mblock_man *mblock, const int element_size,
		const int alloc_elements_once, fast_mblock_alloc_init_func init_func,
        const bool need_lock);

/**
mblock destroy
parameters:
	mblock: the mblock pointer
*/
void fast_mblock_destroy(struct fast_mblock_man *mblock);

/**
alloc a node from the mblock
parameters:
	mblock: the mblock pointer
return the alloced node, return NULL if fail
*/
struct fast_mblock_node *fast_mblock_alloc(struct fast_mblock_man *mblock);

/**
free a node (put a node to the mblock)
parameters:
	mblock: the mblock pointer
	pNode: the node to free
return 0 for success, return none zero if fail
*/
int fast_mblock_free(struct fast_mblock_man *mblock,
		     struct fast_mblock_node *pNode);

/**
delay free a node (put a node to the mblock)
parameters:
	mblock: the mblock pointer
	pNode: the node to free
    delay: delay seconds to free
return 0 for success, return none zero if fail
*/
int fast_mblock_delay_free(struct fast_mblock_man *mblock,
		     struct fast_mblock_node *pNode, const int delay);

/**
alloc a object from the mblock
parameters:
	mblock: the mblock pointer
return the alloced object, return NULL if fail
*/
static inline void *fast_mblock_alloc_object(struct fast_mblock_man *mblock)
{
    struct fast_mblock_node *node;
    node = fast_mblock_alloc(mblock);
    if (node == NULL)
    {
        return NULL;
    }
    return node->data;
}

/**
free a object (put the object to the mblock)
parameters:
	mblock: the mblock pointer
	object: the object to free
return 0 for success, return none zero if fail
*/
static inline int fast_mblock_free_object(struct fast_mblock_man *mblock,
        void *object)
{
    return fast_mblock_free(mblock, fast_mblock_to_node_ptr(object));
}

/**
delay free a object (put a node to the mblock)
parameters:
	mblock: the mblock pointer
	pNode: the node to free
    delay: delay seconds to free
return 0 for success, return none zero if fail
*/
static inline int fast_mblock_delay_free_object(struct fast_mblock_man *mblock,
        void *object, const int delay)
{
    return fast_mblock_delay_free(mblock, fast_mblock_to_node_ptr(object), delay);
}

/**
get node count of the mblock
parameters:
	mblock: the mblock pointer
return the free node count of the mblock, return -1 if fail
*/
int fast_mblock_free_count(struct fast_mblock_man *mblock);

/**
get delay free node count of the mblock
parameters:
	mblock: the mblock pointer
return the delay free node count of the mblock, return -1 if fail
*/
int fast_mblock_delay_free_count(struct fast_mblock_man *mblock);

#define fast_mblock_total_count(mblock) (mblock)->total_count

#ifdef __cplusplus
}
#endif

#endif