proceeding_dispatch.cpp

操作系统实验

#include "stdio.h"
#include "stdlib.h"
#include "string.h"   
 
        struct   pcb{     /*进程控制块的结构*/   
        char   name[8];   
        int     runtime,needtime;
		int    priority;   
        char   status;   
        struct     pcb       *next;   
        };   
      struct   pcb   *s;   
      int   count=0;     /*运行所需要的总时间*/   
  /*创建若干进程,当输入进程需要运行的时间为0时停止输入*/   
  void  creatprocess(s)   
      {char     n[8];   
      int           time,prio;   
      struct     pcb       *p=s,*q;   
    
      while(1)     /*输入进程及其运行时间*/   
        {printf("\n   Please   input   the   name   of   the   process:");   
          scanf("%s",&n);   
          printf("Please   input   the   time   of   the   process:");   
          scanf("%d",&time); 
		  printf("please input the priority of the process:");
		  scanf("%d",& prio);  
          count+=time;   
          if(time==0)       break;     /*当输入进程需要运行的时间为0时停止输入*/   
          q=(struct     pcb   *)malloc(sizeof(struct       pcb));   
          strcpy(q->name,n);         /*初始化进程控制块*/   
          q->runtime=0;   
          q->needtime=time;
		  q->priority= prio;   
          q->status='Ready';   
          p->next=q;   
          p=p->next;
		  free(q);   
            }   
            
      }   
	  
/*将进程按优先权排序*/
void sort(&s)
{

}	  
	   
  /*打印子程序*/   
     void   printpcbline()   
        {struct   pcb   *p;   
            printf("\nname   runtime     needtime     status\n");   
          printf("%s\t%d\t%d\t%c\n",s->name,s->runtime,s->needtime,s->status);   
                                          p=s->next;   
          while(p!=s)   
        {     printf("%s\t%d\t%d\t%c\n",p->name,p->runtime,p->needtime,p->status);   
              p=p->next;   
        }   
  }   
 void runpcbline()/*模拟调度子程序*/   
  {       struct   pcb   *p;   
          int   c;   
      do{   s->runtime+=1;/*运行一次*/   
                    count=count-1;   
            if(s->runtime==s->needtime)/*该进程运行完成*/   
              {     s->status='E';   /*改变其状态*/   
                  printpcbline(     );   
                  p=s;   
              /*删除已完成的进程*/   
                if(s->next!=s)/*进程队列中不止一个进程*/   
  {   
      while(p->next!=s)   
          p=p->next;   
      p->next=s->next;   
  }   
  else   
      s=NULL;   
  if(s!=NULL)   
      s=s->next;   
                }   
            else     s=s->next;   
        if(s!=NULL)   
            printpcbline();   
        printf("   Is   there   a   new   pcb(1/0)?");   
          scanf("%d",&c);   
        printf("%c",c);   
        if(c==1)       {/*有新进程则插入队列*/   
           void insert();   
        printpcbline();   
          }   
      }while(count>0);   
    }   
  /*插入新进程*/   
void insert()   
  {   struct   pcb   *r,*p;   
    r=(struct   pcb*)malloc(sizeof(struct   pcb));   
    printf("Please   input   the   name   of   the   new   pcb:");   
    scanf("%s",r->name);   
    printf("\nPlease   input   the   needtime   of   the   new   pcb:");   
    scanf("%d",&r->needtime);   
    r->runtime=0;   
    r->status='R';   
    count+=r->needtime;   
  if(s!=NULL)   
  {   
      p=s;   
      while(p->next!=s)   p=p->next;   
      r->next=s;   
      p->next=r;   
  }   
  else   
  {s=r;   
    s->next=s;   
    }   
    
  }   
    
  main()   
  {s=(struct   pcb   *)malloc(sizeof(struct   pcb));
   s=NULL;   
    creatpcbline();   
    printpcbline();   
    runpcbline();   
    printf("All   the   process   has   finished!");   
     
  }