mainstore.c

操作系统实验源代码 用C++写的 包括 进程调度

//zhuchukongjianfenpei.c 
#include "stdio.h"
#include "stdlib.h"
#include "string.h"
#define MAX 32767
typedef struct node    /*设置分区描述器*/
{
    int address,size;
    struct node *next;
}RECT;
/*函数原型*/
RECT *assignment(RECT *head,int application);
void acceptment1(RECT *head,RECT *back1);
void acceptment2(RECT *head,RECT *back1) ;
int backcheck(RECT *head,RECT *back1);
void print(RECT *head);
/*变量声明*/
RECT *head,*back,*assign1,*p;
int application1,maxblocknum;
char way;
/*主函数*/
main()
{
    char choose[10];
    int check;
    head=malloc(sizeof(RECT)); /*建立可利用区表的初始状态*/
    p=malloc(sizeof(RECT));
    head->size=MAX;
    head->address=0;
    head->next=p;
    maxblocknum=1;
    p->size=MAX;
    p->address=0;
    p->next=NULL;
    print(head);   /*输出可利用表初始状态*/
    printf("Enter the way(best or first(b/f)\n");/*选择适应策略*/
    scanf("%c",&way);
    do{
       printf("Enter the assign or accept(as/ac)\n");
       scanf("%s",choose); /*选择分配或回收*/
       if(strcmp(choose,"as")==0) /*as为分配*/
       {
   printf("Input application:\n");
   scanf("%d",&application1);/*输入申请空间大小*/
   assign1=assignment(head,application1);/*调用分配函数*/
   if(assign1->address==-1)/*分配不成功*/
      printf("Too large application!,assign fails!!\n\n");
   else
      printf("Success!!ADDRESS=%5d\n",assign1->address); /*分配成功*/
   print(head); /*输出*/
       }
       else
   if(strcmp(choose,"ac")==0) /*回收*/
   {
      back=malloc(sizeof(RECT));
      printf("Input Adress and Size!!\n");
      scanf("%d%d",&back->address,&back->size);/*输入回收地址和大小*/
      check=backcheck(head,back); /*检查*/
      if(check==1)
      {
         if(tolower(way)=='f')/*首先适应算法*/
     acceptment1(head,back); /*首先适应*/
         else
     acceptment2(head,back);/*最佳适应*/
         print(head);
      }
   }
    }while(!strcmp(choose,"as")||!strcmp(choose,"ac"));
}
/*分配函数*/
RECT *assignment(RECT *head,int application)
{
    RECT *after,*before,*assign;
    assign=malloc(sizeof(RECT)); /*分配申请空间*/
    assign->size=application;
    assign->next=NULL;
    if(application>head->size||application<=0)
       assign->address=-1; /*申请无效*/
    else
    {
       before=head;
       after=head->next;
       while(after->size<application)/*查找适应的结点*/
       {
   before=before->next;
   after=after->next;
       }
       if(after->size==application) /*结点大小等于申请大小则完全分配*/
       {
   if(after->size==head->size)
      maxblocknum--;
   before->next=after->next;
   assign->address=after->address;
   free(after);
       }
       else
       {
   if(after->size==head->size) maxblocknum--;
   after->size=after->size-application; /*大于申请空间则截取相应大小分配*/
   assign->address=after->address+after->size;
   if(tolower(way)=='b')/*如果是最佳适应，将截取后剩余结点重新回收到合适位置*/
   {
      before->next=after->next;
      back=after;
      acceptment2(head,back);
   }
       }
       if(maxblocknum==0) /*修改最大数和头结点值*/
       {
   before=head;
   head->size=0;
   maxblocknum=1;
   while(before!=NULL)
   {
      if(before->size>head->size)
      {
         head->size=before->size;
         maxblocknum=1;
      }
      else
         if(before->size==head->size)
     maxblocknum++;
      before=before->next;
   }
       }
    }
    assign1=assign;
    return assign1; /*返回分配给用户的地址*/
}
void acceptment1(RECT *head,RECT *back1)/*首先适应*/
{
    RECT *before,*after;
    int insert;
    before=head;
    after=head->next;
    insert=0;
    while(!insert) /*将回收区插入空闲区表*/
    {
       if((after==NULL)||
   ((back1->address<=after->address)&&
     (back1->address>=before->address)))
       {
   before->next=back1;
   back1->next=after;
   insert=1;
       }
       else
       {
   before=before->next;
   after=after->next;
       }
    }
    if(back1->address==before->address+before->size)/*与上一块合并*/
    {
       before->size=before->size+back1->size;
       before->next=back1->next;
       free(back1);
       back1=before;
    }
    if(after!=NULL&&(after->address==back1->address+back1->size))
    {   /*与下一块合并*/
       back1->size=back1->size+after->size;
       back1->next=after->next;
       free(after);
    }
    if(head->size<back1->size) /*修改最大块值和最大块个数*/
    {
       head->size=back1->size;
       maxblocknum=1;
    }
    else
       if(head->size==back1->size)
   maxblocknum++;
}
/*最佳适应，back1为回收结点的地址*/
void acceptment2(RECT *head,RECT *back1)
{
    RECT *before,*after;
    int insert ;
    insert=0;
    before=head;
    after=head->next;
    if(head->next==NULL) /*如果可利用区表为空*/
    {
       head->size=back1->size;
       head->next=back1;
       maxblocknum++;
       back1->next=NULL;
    }
    else
    {
       while(after!=NULL) /*与上一块合并*/
       if(back1->address==after->size+after->address)
       {
   before->next=after->next;
   back->size=after->size+back1->size;
   free(after);
   after=NULL;
       }
       else
       {
   after=after->next;
   before=before->next;
       }
       before=head;
       after=head->next;
       while(after!=NULL)
       if(after->address==back1->size+back1->address) /*与下一块合并*/
       {
   back1->size=back1->size+after->size;
   before->next=after->next;
   free(after);
   after=NULL;
       }
       else
       {
   before=before->next;
   after=after->next;
       }
       before=head;/*将回收结点插入到合适的位置*/
       after=head->next;
       do{
   if(after==NULL||(after->size>back1->size))
   {
      before->next=back1;
      back1->next=after;
      insert=1;
   }
   else
   {
      before=before->next;
      after=after->next;
   }
       }while(!insert);
       if(head->size<back1->size) /*修改最大块值和最大块数*/
       {
   head->size=back1->size;
   maxblocknum++;
       }
       else
   if(head->size==back1->size)
      maxblocknum++;
    }
}

void print(RECT *head) /*输出链表*/
{
    RECT *before,*after;
    int index,k;
    before=head->next;
    index=1;
    if(head->next==NULL)
       printf("NO part for assignment!!\n");
    else
    {
       printf("*****index*******address********end*********size*****\n");
       while(before!=NULL)
       {
   printf("----------------------------------------------------\n");
   printf("      %-13d%-13d%-13d%-13d\n",index,before->address,before->address+before->size-1,before->size);
   printf("----------------------------------------------------\n");
   index++;
   before=before->next;
       }
    }
}
/*检查回收块的合法性，back1为要回收的结点地址*/
int backcheck(RECT *head,RECT *back1)
{
    RECT *before,*after;
    int check=1;
    if(back1->address<0||back1->size<0)
       check=0;/*地址和大小不能为负*/
    before=head->next;
    while((before!=NULL)&&check)/*地址不能和空闲区表中结点出现重叠*/
       if(((back1->address<before->address)
   &&(back1->address+back1->size>before->address))
   ||((back1->address>=before->address)
&&(back1->address<before->address+before->size)))
   check=0;
       else
   before=before->next;
    if(check==0)
       printf("Error input!!\n");
    return check;   /*返回检查结果*/
}