实验4.cpp

操作系统实验 文件管理 实现建立目录

#include "iostream.h"
#include "stdlib.h"
#include "string.h"
#include <iomanip.h>
typedef struct node
{
	int suoyin;
	char name[20];
	int len;
	char type[10];
	int father;
	struct node *next;
	int child[20];
	int top;
}tree;
tree *root,*rr;
tree *thist=NULL;
int jilu=1;
void init()
{
	
	root=new node;
    root->father=0;
	root->suoyin=jilu;
	strcpy(root->type,"<dir>");
    strcpy(root->name,"C:\\"); 
    root->top=-1;
	rr=root;
	rr->next=NULL;
	jilu++;
	thist=root;
}
void md()
{
  
   char name[20];
   cin>>name;
   int flag=0;
   tree *yy;
   yy=thist->next;
   while(yy!=NULL)
   {
	   if(strcmp(yy->name,name)==0&&strcmp(yy->type,"<dir>")==0)
	   {
		   flag=1;
		   break;
	   }
	   else
		   yy=yy->next;
   }
   if(flag==1)
   {
	   cout<<"子目录或文件 "<<name<<" 已经存在。"<<endl;
   }
   else
   {
      tree *t1;
      t1=new node;
      strcpy(t1->name,name);
      strcpy(t1->type,"<dir>");
      t1->suoyin=jilu;
	  t1->father=thist->suoyin;
	  t1->top=-1;
	  rr->next=t1;
	  rr=t1;
	  rr->next=NULL;
	  thist->top++;
	  thist->child[thist->top]=jilu;
	  jilu++;  
	 }
}
void mk()
{
   char name[20];
   cin>>name;
   int flag=0;
   tree *yy;
   yy=thist->next;
   while(yy!=NULL)
   {
	   if(strcmp(yy->name,name)==0&&strcmp(yy->type,"file")==0)
	   {
		   flag=1;
		   break;
	   }
	   else
		   yy=yy->next;
   }
   if(flag==1)
   {
	   cout<<"子目录或文件 "<<name<<" 已经存在。"<<endl;
   }
   else
   {
       tree *t1;
       t1=new node;
       strcpy(t1->name,name);
	   t1->len=rand()%10;
	   t1->suoyin=jilu;
       t1->father=thist->suoyin;
	   t1->top=-1;
	   strcpy(t1->type,"file");
       rr->next=t1;
       rr=t1;
       rr->next=NULL;
	   thist->top++;
       thist->child[thist->top]=jilu;    
	   jilu++;
   }
}
void cd()
{
	char name[20];
    cin>>name;
	tree *t1;
	int flag=0;
	if(strcmp(name,"\\")==0)
	{
		thist=root;
	}
	else 
		if(strcmp(name,"..")==0)
		{
		   tree *yy;
		   yy=root;
           while(yy!=NULL)
		   {
	         if(yy->suoyin==thist->father)
			 {
		        thist=yy;
		        break;
			 }
	         else
		        yy=yy->next;
		   }

		}
	   else
	   {
	     for(int i=0;i<=thist->top;i++)
		 {
		     t1=thist->next;
		     while(t1!=NULL)
			 {
			      if(strcmp(t1->name,name)==0&&strcmp(t1->type,"<dir>")==0)
				  {
				     thist=t1;
			         flag=1;
				     break;
				  }
			      else
				       t1=t1->next ;
			 }
		 }	
	    if(flag==0)
		     cout<<"系统找不到指定路径。"<<endl;
	   }
}
void dir()
{
	tree *t1;
	int m=2,w=0;
    cout<<"            "<<thist->type<<setw(10)<<"."<<endl;
    cout<<"            "<<thist->type<<setw(10)<<".."<<endl;
    for(int i=0;i<=thist->top;i++)
	{
		t1=thist->next;
		while(t1!=NULL)
		{
            if(t1->suoyin==thist->child[i])
			{
			   if(strcmp(t1->type,"<dir>")==0)
			   {
				   cout<<"       "<<setw(10)<<t1->type<<setw(10)<<t1->name<<endl;
				   m++;
			   }
			   else 
			   {
				   cout<<"       "<<setw(10)<<t1->len<<setw(10)<<t1->name<<endl;
		    	   w++;
			   }
			   break;
			}
			else
				   t1=t1->next;
		}
	}
	cout<<setw(20)<<w<<"  个文件"<<endl;
	cout<<setw(20)<<m<<"  个目录"<<endl;

}
void rd()
{
	char name[20];
    cin>>name;
	tree *yy,*tmp,*t1;
	int flag=0;
	yy=thist->next;
	while(yy!=NULL)
	{
		if(strcmp(yy->name,name)==0&&strcmp(yy->type,"<dir>")==0)
		{
			tmp=yy;
			flag=1;
			break;
		}
		else  yy=yy->next ;
	}
	if(flag==0)
		cout<<"系统找不到指定文件。"<<endl;
	else
	{
		if(tmp->top!=-1)
			cout<<"目录不是空的。"<<endl;
		else
		{
             yy=root;
	         for(int i=0;i<=jilu;i++)
			 {
		            if(yy->suoyin==tmp->suoyin-1)
					{
		               	t1=yy;
		            	break;
					}
		            else  yy=yy->next ;
			 }
	         int j1,j;
	         for(j=0;j<=thist->top;j++)
			 {
		           if(thist->child[j]==tmp->suoyin)
				   {
		          	     j1=j;
			             break;
				   }
			 }
	         for(j=j1;j<=thist->top;j++)
			 {
		           thist->child[j]=thist->child[j+1];
			 }
	         if(tmp==rr)
			 {
	             	rr=t1;
		            rr->next=NULL;
			 }
	         else
		          t1->next=tmp->next ;
		}
		jilu--;
	}


}
void del()
{
	char name[20];
    cin>>name;
	tree *yy,*tmp,*t1;
	int flag=0;
	yy=thist;
	while(yy!=NULL)
	{
		if(strcmp(yy->name,name)==0&&strcmp(yy->type,"file")==0)
		{
			tmp=yy;
			flag=1;
			break;
		}
		else  yy=yy->next ;
	}
	if(flag==0)
		cout<<"系统找不到指定文件。"<<endl;
	else
	{
        yy=root;
	    for(int i=0;i<=jilu;i++)
		{
		       if(yy->suoyin==tmp->suoyin-1)
			   {
		          	t1=yy;
		        	break;
			   }
		       else  yy=yy->next ;
		}
	    int j1,j;
	    for(j=0;j<=thist->top;j++)
		{
		       if(thist->child[j]==tmp->suoyin)
			   {
		          	j1=j;
			        break;
			   }
		}
	    for(j=j1;j<=thist->top;j++)
		{
		    thist->child[j]=thist->child[j+1];
		}
	    if(tmp==rr)
		{
	           	rr=t1;
		        rr->next=NULL;
		}
	    else
		         t1->next=tmp->next ;
		jilu--;
	}
}
void main()
{
	init();
	cout<<"C:\\>";
	char a[4];
	do
	{
	     cin>>a;
         if(strcmp(a,"md")==0)
	              md();
	     else if(strcmp(a,"cd")==0)
	              cd();
         else if(strcmp(a,"rd")==0)
		          rd();
	     else if(strcmp(a,"mk")==0)
		          mk();
	     else if(strcmp(a,"dir")==0)
	              dir();
	     else if(strcmp(a,"del")==0)
		          del();
	     if(thist==root)
		     cout<<thist->name<<">";
	     else
		      cout<<"C:\\"<<thist->name<<">";
	}
	while(1);
}