chain.h

来自「AMLOGIC DPF source code」· C头文件 代码 · 共 204 行

/*******************************************************************
 * 
 *  Copyright C 2005 by Amlogic, Inc. All Rights Reserved.
 *
 *  Description: 
 *
 *  Author: Amlogic Software
 *  Created: Fri Nov 11 01:04:28 2005
 *
 *******************************************************************/
/*  chain.h
 *
 *  This include file contains all the constants and structures associated
 *  with the Doubly Linked Chain Handler.
 *
 *  COPYRIGHT (c) 1989-1999.
 *  On-Line Applications Research Corporation (OAR).
 *
 *  The license and distribution terms for this file may be
 *  found in the file LICENSE in this distribution or at
 *  http://www.avfs.com/license/LICENSE.
 *
 *  chain.h,v 1.11.6.1 2003/09/04 18:55:05 joel Exp
 */

#ifndef __AVFS_CHAIN_h
#define __AVFS_CHAIN_h

#ifdef __cplusplus
extern "C" {
#endif

//#include <avfs/score/address.h>
//porting
#include "address.h"

/*
 *  This is used to manage each element (node) which is placed
 *  on a chain.
 *
 *  NOTE:  Typically, a more complicated structure will use the
 *         chain package.  The more complicated structure will
 *         include a chain node as the first element in its
 *         control structure.  It will then call the chain package
 *         with a pointer to that node element.  The node pointer
 *         and the higher level structure start at the same address
 *         so the user can cast the pointers back and forth.
 *
 */

typedef struct Chain_Node_struct Chain_Node;

struct Chain_Node_struct {
  Chain_Node *next;
  Chain_Node *previous;
};

/*
 *  This is used to manage a chain.  A chain consists of a doubly
 *  linked list of zero or more nodes.
 *
 *  NOTE:  This implementation does not require special checks for
 *         manipulating the first and last elements on the chain.
 *         To accomplish this the chain control structure is
 *         treated as two overlapping chain nodes.  The permanent
 *         head of the chain overlays a node structure on the
 *         first and permanent_null fields.  The permanent tail
 *         of the chain overlays a node structure on the
 *         permanent_null and last elements of the structure.
 *
 */

typedef union Chain_Control_S
{
		struct {
	      Chain_Node *first;
	      Chain_Node *permanent_null;
	      Chain_Node *last;
	    } chain_node;
	    struct {
	      Chain_Node  head;
	      Chain_Node *head_dummy;
	    } chain_head;
	    struct{
	      Chain_Node *tail_dummy;
	      Chain_Node  tail;
	    } chain_tail;
} Chain_Control;

/*
 *  _Chain_Initialize
 *
 *  DESCRIPTION:
 *
 *  This routine initializes the_chain structure to manage the
 *  contiguous array of number_nodes nodes which starts at
 *  starting_address.  Each node is of node_size bytes.
 *
 */

void _Chain_Initialize(
  Chain_Control *the_chain,
  void          *starting_address,
  unsigned32     number_nodes,
  unsigned32     node_size
);

/*
 *  _Chain_Get_first_unprotected
 */
Chain_Node *_Chain_Get_first_unprotected(
  Chain_Control *the_chain
);

/*
 *  _Chain_Extract
 *
 *  DESCRIPTION:
 *
 *  This routine extracts the_node from the chain on which it resides.
 *  It disables interrupts to insure the atomicity of the
 *  extract operation.
 *
 */

void _Chain_Extract(
  Chain_Node *the_node
);

/*
 *  _Chain_Get
 *
 *  DESCRIPTION:
 *
 *  This function removes the first node from the_chain and returns
 *  a pointer to that node.  If the_chain is empty, then NULL is returned.
 *  It disables interrupts to insure the atomicity of the
 *  get operation.
 *
 */

Chain_Node *_Chain_Get(
  Chain_Control *the_chain
);

/*
 *  _Chain_Insert
 *
 *  DESCRIPTION:
 *
 *  This routine inserts the_node on a chain immediately following
 *  after_node.  It disables interrupts to insure the atomicity
 *  of the extract operation.
 *
 */

void _Chain_Insert(
  Chain_Node *after_node,
  Chain_Node *the_node
);

/*
 *  _Chain_Append
 *
 *  DESCRIPTION:
 *
 *  This routine appends the_node onto the end of the_chain.
 *  It disables interrupts to insure the atomicity of the
 *  append operation.
 *
 */

void _Chain_Append(
  Chain_Control *the_chain,
  Chain_Node    *the_node
);


boolean _Chain_Is_empty(
  Chain_Control *the_chain
);

Chain_Node *_Chain_Get_first_unprotected(
  Chain_Control *the_chain
);

void _Chain_Initialize_empty(
  Chain_Control *the_chain
);

#ifndef __AVFS_APPLICATION__
//#include <avfs/score/chain.inl>
//porting
//#include <chain.inl>
//#include <chain_.h>
#endif

#ifdef __cplusplus
}
#endif

#endif
/* end of include file */