dchain.hpp

一款运行于ARM上的文件系统

//                        文件名：DChain.hpp
//文本：
//         本文件提供双向链表类，该链表中的每一个结构有两个指针，一个指向上一
//      个结构，另一个指向下一个结构，最后一个结构的指向下一个结构的指针指向0
//      ，由此构成一个循环链表结构。
//
//
//
//
//
//创建人：陈子牙
//创建日期：2006/04/15

#ifndef ERR
#define ERR -1
#endif
#define OK   1



//
//                        双向链表类
//
//
//
//
//
//
template <class Type>
class CDchainP{
protected:
//
//双向链表子项类
//
//
//
//
template <class Type>
class CDchainInfoP{
public:
    int hchain;                  //该子项的唯一标识符
    CDchainInfoP<Type>* p_next_note;    //指向下一个链表子项的指针
    CDchainInfoP<Type>* p_last_note;    //指向上一个链表子项的指针
public:
    Type* ptype;          //指向数据结构的指针
};




    int m_count;                            //用于记录该链表中子项的数目
    int m_handcount;                        //用于给每个链表子项赋值
    CDchainInfoP<Type>* p_first_item;              //指向第一个链表子项的指针
    CDchainInfoP<Type>* p_end_item;                //指向最后一个链表子项的指针
    CDchainInfoP<Type>* p_current_item;
public:
    //
    //
    //
    CDchainP()
    {
        m_count=0;
        m_handcount=0;
        p_first_item=(CDchainInfoP<Type>*)0;
        p_end_item=(CDchainInfoP<Type>*)0;
        p_current_item=(CDchainInfoP<Type>*)0;
    }
    //
    //
    //
    ~CDchainP()
    {
        CDchainInfoP<Type>* pcurrent=p_first_item;
        for(int i=0;i<m_count;i++)
        {
            
        }
    }




    //在链表尾插入数据
    //输入参数：
    //返回参数：
    //版本：    V1.0.0
    int fnAddItem(Type* pdat)
    {
        CDchainInfoP<Type> *newchain=new CDchainInfoP<Type>;
        newchain->ptype=pdat;
        if(m_count==0)
        {
            newchain->p_last_note=0;
            newchain->p_next_note=0;
            p_first_item=newchain;
            p_end_item=newchain;
            p_current_item=newchain;
        }
        else
        {
            newchain->p_last_note=p_end_item;
            newchain->p_next_note=0;
            p_end_item->p_next_note=newchain;
            p_end_item=newchain;
        }
        ++m_handcount;
        ++m_count;
        newchain->hchain=m_handcount;
        return m_handcount;
    }




    //以顺序位置为变量插入数据
    //输入参数：
    //返回参数：
    //版本：    V1.0.0
    int fnAddItem(Type* pdat,int sequence)
    {int i=0;
        CDchainInfoP<Type> *newchain=new CDchainInfoP<Type>;
        CDchainInfoP<Type>* pcurrent=p_first_item;
        newchain->ptype=pdat;
        if(m_count==0)
        {
            return fnAddItem(pdat);
        }
        else
        {
            if(sequence ==  0)
        	{
                newchain->p_last_note=0;
                newchain->p_next_note=p_first_item;
                pcurrent->p_last_note=newchain;
                p_first_item=newchain;
                ++m_handcount;
                ++m_count;
                newchain->hchain=m_handcount;
                return m_handcount;
        	}
            else if(sequence >= m_count)
        	{
                return fnAddItem(pdat);
        	}
            else
            { 
                while(++i<sequence)
            	{
                    pcurrent=pcurrent->p_next_note;
            	}
                newchain->p_last_note=pcurrent;
                newchain->p_next_note=pcurrent->p_next_note;
                (pcurrent->p_next_note)->p_last_note=newchain;
                pcurrent->p_next_note=newchain;
                ++m_handcount;
                ++m_count;
                newchain->hchain=m_handcount;
                return m_handcount;
        	}
        }
    }




    //以句柄删除数据
    //输入参数：
    //返回参数：
    //版本：    V1.0.0
    void fnDelItem(int hchain)
    {int i=0;
     CDchainInfoP<Type>* pcurrent=p_first_item;
     p_current_item=p_first_item;
        if(m_count==0)
        {
            return;
        }
        if(m_count==1)
        {
            p_first_item=0;
            p_end_item=0;
            p_current_item=0;
            m_count--;
            delete pcurrent;
            return ;
        }
        for(i=0;i<m_count;i++)
        {
            if(pcurrent->hchain==hchain)
        	{
               
               if(i==0)
               {
                   (pcurrent->p_next_note)->p_last_note=0;
                    m_count--;
                   delete pcurrent;
                   return;
               }
               if(i==m_count-1)
               {
                   (pcurrent->p_last_note)->p_next_note=0;
                    m_count--;
                   delete pcurrent;
                   return;
               }
                   (pcurrent->p_next_note)->p_last_note=pcurrent->p_last_note;
                   (pcurrent->p_last_note)->p_next_note=pcurrent->p_next_note;
                   m_count--;
               delete pcurrent;
               return;
        	}
            pcurrent=pcurrent->p_next_note;
        }
    }



    //以顺序位置删除数据
    //输入参数：
    //返回参数：
    //版本：    V1.0.0
    int fnDelItemWithSequence(int sequence)
    {
        CDchainInfoP<Type>* pcurrent=p_first_item;
        p_current_item=p_first_item;
        if(m_count==0)
        {
            return  ERR;
        }
        if(m_count==1)
        {
            p_first_item=0;
            p_end_item=0;
            p_current_item=0;
            m_count--;
            delete pcurrent;
            return OK;
        }
            if(sequence==m_count-1)
        	{
                pcurrent=p_end_item;
                (p_end_item->p_last_note)->p_next_note=0;
                p_end_item=p_end_item->p_last_note;
                m_count--;
                delete pcurrent;
                return OK;
        	}
            if(sequence==0)
        	{
                (p_first_item->p_next_note)->p_last_note=0;
                p_first_item=p_first_item->p_next_note;
                m_count--;
                delete pcurrent;
                return OK;
        	}

            if(sequence >= m_count)
                return ERR;
            int i=0;
            while(i++<sequence)
        	{
                pcurrent=pcurrent->p_next_note;
        	}
            m_count--;
            (pcurrent->p_last_note)->p_next_note=pcurrent->p_next_note;
            (pcurrent->p_next_note)->p_last_note=pcurrent->p_last_note;
            delete pcurrent;
            return OK;
    }




    //以句柄获取数据
    //输入参数：
    //返回参数：
    //版本：    V1.0.0
    Type* fnGet(int hchain)
    {
     CDchainInfoP<Type>* pcurrent=p_first_item;
        for(int i=0;i<m_count;i++)
        {
            if(pcurrent->hchain==hchain)
        	{
                return pcurrent->ptype;
        	}
            pcurrent=pcurrent->p_next_note;
        }
        return   (Type*)0;
    }




    //以顺序位置获取数据
    //输入参数：
    //返回参数：
    //版本：    V1.0.0
    Type* operator [](int sequence)
    {
        CDchainInfoP<Type>* pcurrent=p_first_item;
        if(sequence >= m_count)
            return (Type*)0;
                for(int i=0;i<sequence;i++)
            	{
                    pcurrent=pcurrent->p_next_note;
            	}
                return pcurrent->ptype;
    }




    //获取结构的数目
    //输入参数：
    //返回参数：
    //版本：    V1.0.0
    int fnCount(void)
    {
        return   m_count;
    }



    //获取下一个结构的指针
    //输入参数：
    //返回参数：
    //版本：    V1.0.0
    Type* operator ++()
    {
        if(m_count==0)
           return(0);
        if(p_current_item!=0)
        {
            if(p_current_item->p_next_note==0)
        	{
                return 0;
        	}
            else
        	{
                p_current_item=p_current_item->p_next_note;
                return(p_current_item->ptype);
        	}
        }
        else
            return 0;
    }


    //获取上一个结构的指针
    //输入参数：
    //返回参数：
    //版本：    V1.0.0
    Type* operator --()
    {
        if(m_count==0)
           return(0);
        if(p_current_item!=0)
        {
            if(p_current_item->p_last_note==0)
        	{
                return 0;
        	}
            else
        	{
                p_current_item=p_current_item->p_last_note;
                return(p_current_item->ptype);
        	}
        }
        else
            return 0;
    }


    //
    //输入参数：
    //返回参数：
    //版本：    V1.0.0
    void fnprintf(void)
    {CDchainInfoP<Type>* pcurrent=p_first_item;
    cout<<"m_count    :"<<m_count<<endl;
    cout<<"m_handcount:"<<m_handcount<<endl;
    cout<<"p_first_item:"<<p_first_item<<endl;
    cout<<"p_end_item:"<<p_end_item<<endl;
while(pcurrent!=0)
    {
        cout<<"$$"<<endl;
        cout<<"pcurrent->this:        "<<pcurrent<<endl;
        cout<<"pcurrent->hchain:      "<<pcurrent->hchain<<endl;
        cout<<"pcurrent->p_next_note: "<<pcurrent->p_next_note<<endl;
        cout<<"pcurrent->p_last_note: "<<pcurrent->p_last_note<<endl;
        cout<<"pcurrent->ptype:       "<<pcurrent->ptype<<endl;
        cout<<"$$"<<endl;
        pcurrent=pcurrent->p_next_note;
    }
    }
};


/*
 *
 *
 *
 *
 *
 8
 *
 *
 *
 *
 *
 *
 *
 *
 *
 */