操作系统课的实验（银行家算法）#include "malloc.h"
#include "stdio.h"
#include "stdlib.h"
#define alloclen sizeof(struct allocation)
#define maxlen sizeof(struct max)
#define avalen sizeof(struct available)
#define needlen sizeof(struct need)
#define finilen sizeof(struct finish)
#define pathlen sizeof(struct path)
struct allocation
{
int value;
struct allocation *next;
};
struct max
{
int value;
struct max *next;
};
struct available /*可用资源数*/
{
int value;
struct available *next;
};
struct need /*需求资源数*/
{
int value;
struct need *next;
};
struct path
{
int value;
struct path *next;
};
struct finish
{
int stat;
struct finish *next;
};
int main()
{
int row,colum,status=0,i,j,t,temp,processtest;
struct allocation *allochead,*alloc1,*alloc2,*alloctemp;
struct max *maxhead,*maxium1,*maxium2,*maxtemp;
struct available *avahead,*available1,*available2,*workhead,*work1,*work2,*worktemp,*worktemp1;
struct need *needhead,*need1,*need2,*needtemp;
struct finish *finihead,*finish1,*finish2,*finishtemp;
struct path *pathhead,*path1,*path2;
printf("\n请输入系统资源的种类数:");
scanf("%d",&colum);
printf("请输入现时内存中的进程数:");
scanf("%d",&row);
printf("请输入已分配资源矩阵:\n");
for(i=0;i<row;i++)
{
for (j=0;j<colum;j++)
{
printf("请输入已分配给进程 p%d 的 %c 种系统资源:",i,'A'+j);
if(status==0)
{
allochead=alloc1=alloc2=(struct allocation*)malloc(alloclen);
alloc1->next=alloc2->next=NULL;
scanf("%d",&allochead->value);
status++;
}
else
{
alloc2=(struct allocation *)malloc(alloclen);
scanf("%d,%d",&alloc2->value);
if(status==1)
{
allochead->next=alloc2;
status++;
}
alloc1->next=alloc2;
alloc1=alloc2;
}
}
}
alloc2->next=NULL;
status=0;
printf("请输入最大需求矩阵:\n");
for(i=0;i<row;i++)
{
for (j=0;j<colum;j++)
{
printf("请输入进程 p%d 种类 %c 系统资源最大需求:",i,'A'+j);
if(status==0)
{
maxhead=maxium1=maxium2=(struct max*)malloc(maxlen);
maxium1->next=maxium2->next=NULL;
scanf("%d",&maxium1->value);
status++;
}
else
{
maxium2=(struct max *)malloc(maxlen);
scanf("%d,%d",&maxium2->value);
if(status==1)
{
maxhead->next=maxium2;
status++;
}
maxium1->next=maxium2;
maxium1=maxium2;
}
}
}
maxium2->next=NULL;
status=0;
printf("请输入现时系统剩余的资源矩阵:\n");
for (j=0;j<colum;j++)
{
printf("种类 %c 的系统资源剩余:",'A'+j);
if(status==0)
{
avahead=available1=available2=(struct available*)malloc(avalen);
workhead=work1=work2=(struct available*)malloc(avalen);
available1->next=available2->next=NULL;
work1->next=work2->next=NULL;
scanf("%d",&available1->value);
work1->value=available1->value;
status++;
}
else
{
available2=(struct available*)malloc(avalen);
work2=(struct available*)malloc(avalen);
scanf("%d,%d",&available2->value);
work2->value=available2->value;
if(status==1)
{
avahead->next=available2;
workhead->next=work2;
status++;
}
available1->next=available2;
available1=available2;
work1->next=work2;
work1=work2;
}
}
available2->next=NULL;
work2->next=NULL;
status=0;
alloctemp=allochead;
maxtemp=maxhead;
for(i=0;i<row;i++)
for (j=0;j<colum;j++)
{
if(status==0)
{
needhead=need1=need2=(struct need*)malloc(needlen);
need1->next=need2->next=NULL;
need1->value=maxtemp->value-alloctemp->value;
status++;
}
else
{
need2=(struct need *)malloc(needlen);
need2->value=(maxtemp->value)-(alloctemp->value);
if(status==1)
{
needhead->next=need2;
status++;
}
need1->next=need2;
need1=need2;
}
maxtemp=maxtemp->next;
alloctemp=alloctemp->next;
}
need2->next=NULL;
status=0;
for(i=0;i<row;i++)
{
if(status==0)
{
finihead=finish1=finish2=(struct finish*)malloc(finilen);
finish1->next=finish2->next=NULL;
finish1->stat=0;
status++;
}
else
{
finish2=(struct finish*)malloc(finilen);
finish2->stat=0;
if(status==1)
{
finihead->next=finish2;
status++;
}
finish1->next=finish2;
finish1=finish2;
}
}
finish2->next=NULL; /*Initialization compleated*/
status=0;
processtest=0;
for(temp=0;temp<row;temp++)
{
alloctemp=allochead;
needtemp=needhead;
finishtemp=finihead;
worktemp=workhead;
for(i=0;i<row;i++)
{
worktemp1=worktemp;
if(finishtemp->stat==0)
{
for(j=0;j<colum;j++,needtemp=needtemp->next,worktemp=worktemp->next)
if(needtemp->value<=worktemp->value)
processtest++;
if(processtest==colum)
{
for(j=0;j<colum;j++)
{
worktemp1->value+=alloctemp->value;
worktemp1=worktemp1->next;
alloctemp=alloctemp->next;
}
if(status==0)
{
pathhead=path1=path2=(struct path*)malloc(pathlen);
path1->next=path2->next=NULL;
path1->value=i;
status++;
}
else
{
path2=(struct path*)malloc(pathlen);
path2->value=i;
if(status==1)
{
pathhead->next=path2;
status++;
}
path1->next=path2;
path1=path2;
}
finishtemp->stat=1;
}
else
{
for(t=0;t<colum;t++)
alloctemp=alloctemp->next;
finishtemp->stat=0;
}
}
else
for(t=0;t<colum;t++)
{
needtemp=needtemp->next;
alloctemp=alloctemp->next;
}
processtest=0;
worktemp=workhead;
finishtemp=finishtemp->next;
}
}
path2->next=NULL;
finishtemp=finihead;
for(temp=0;temp<row;temp++)
{
if(finishtemp->stat==0)
{
printf("\n系统处于非安全状态!\n");
exit(0);
}
finishtemp=finishtemp->next;
}
printf("\n系统处于安全状态.\n");
printf("\n安全序列为: \n");
do
{
printf("p%d ",pathhead->value);
}
while(pathhead=pathhead->next);
printf("\n");
return 0;
}
#include "string.h"
#include <stdio.h>
#include <stdlib.h>
#define M 5
#define N 3
#define FALSE 0
#define TRUE 1
/*M个进程对N类资源最大资源需求量*/
int MAX[M][N]={{7,5,3},{3,2,2},{9,0,2},{2,2,2},{4,3,3}};
/*系统可用资源数*/
int AVAILABLE[N]={10,5,7};
/*M个进程对N类资源最大资源需求量*/
int ALLOCATION[M][N]={{0,0,0},{0,0,0},{0,0,0},{0,0,0},{0,0,0}};
/*M个进程已经得到N类资源的资源量 */
int NEED[M][N]={{7,5,3},{3,2,2},{9,0,2},{2,2,2},{4,3,3}};
/*M个进程还需要N类资源的资源量*/
int Request[N]={0,0,0};
void main()
{
int i=0,j=0;
char flag='Y';
void showdata();
void changdata(int);
void rstordata(int);
int chkerr(int);
showdata();
while(flag=='Y'||flag=='y')
{
i=-1;
while(i<0||i>=M)
{
printf("请输入需申请资源的进程号（从0到");
printf("%d",M-1);
printf("，否则重输入!）:");
scanf("%d",&i);
if(i<0||i>=M)printf("输入的进程号不存在，重新输入!\n");
}
printf("请输入进程");
printf("%d",i);
printf("申请的资源数\n");
for (j=0;j<N;j++)
{
printf("资源");
printf("%d",j);
printf(":");
scanf("%d",&Request[j]);
if(Request[j]>NEED[i][j])
{
printf("进程");
printf("%d",i);
printf("申请的资源数大于进程");
printf("%d",i);
printf("还需要");
printf("%d",j);
printf("类资源的资源量!申请不合理，出错!请重新选择!\n");
/*printf("申请不合理，出错!请重新选择!\n");*/
flag='N';
break;
}
else
{
if(Request[j]>AVAILABLE[j])
{
printf("进程");
printf("%d",i);
printf("申请的资源数大于系统可用");
printf("%d",j);
printf("类资源的资源量!申请不合理，出错!请重新选择!\n");
/*printf("申请不合理，出错!请重新选择!\n");*/
flag='N';
break;
}
}
}
if(flag=='Y'||flag=='y')
{
changdata(i);
if(chkerr(i))
{
rstordata(i);
showdata();
}
else
showdata();
}
else
showdata();
printf("\n");
printf("是否继续银行家算法演示,按'Y'或'y'键继续,按'N'或'n'键退出演示: ");
scanf("%c",&flag);
}
}
void showdata()
{
int i,j;
printf("系统可用的资源数为:\n");
printf(" ");
for (j=0;j<N;j++){
printf(" 资源");
printf("%d",j);
printf(":");
printf("%d",AVAILABLE[j]);
/*printf("\n");*/
/* cout<<endl;
// cout<<"各进程资源的最大需求量:"<<endl<<endl;
// for (i=0;i<M;i++)
// {
// cout<<"进程"<<i<<":";
// for (j=0;j<N;j++)cout<<" 资源"<<j<<": "<<MAX[i][j];
// cout<<endl;
*/ }
printf("\n");
printf("各进程还需要的资源量:\n");
for (i=0;i<M;i++)
{
printf(" 进程");
printf("%d",i);
printf(":");
for (j=0;j<N;j++){
printf("资源");
printf("%d",j);
printf(":");
printf("%d",NEED[i][j]);
/*printf("\n");*/
}
printf("\n");
}
printf("各进程已经得到的资源量: \n");
for (i=0;i<M;i++)
{
printf(" 进程");
printf("%d",i);
/*printf(":\n");*/
for (j=0;j<N;j++){
printf("资源");
printf("%d",j);
printf(":");
printf("%d",ALLOCATION[i][j]);
/*printf("\n");*/
}
printf("\n");
}
}
void changdata(int k)
{
int j;
for (j=0;j<N;j++)
{
AVAILABLE[j]=AVAILABLE[j]-Request[j];
ALLOCATION[k][j]=ALLOCATION[k][j]+Request[j];
NEED[k][j]=NEED[k][j]-Request[j];
}
};
void rstordata(int k)
{
int j;
for (j=0;j<N;j++)
{
AVAILABLE[j]=AVAILABLE[j]+Request[j];
ALLOCATION[k][j]=ALLOCATION[k][j]-Request[j];
NEED[k][j]=NEED[k][j]+Request[j];
}
};
int chkerr(int s)
{
int WORK,FINISH[M],temp[M];
int i,j,k=0;
for(i=0;i<M;i++)FINISH[i]=FALSE;
for(j=0;j<N;j++)
{
WORK=AVAILABLE[j];
i=s;
while(i<M)
{
if (FINISH[i]==FALSE&&NEED[i][j]<=WORK)
{
WORK=WORK+ALLOCATION[i][j];
FINISH[i]=TRUE;
temp[k]=i;
k++;
i=0;
}
else
{
i++;
}
}
for(i=0;i<M;i++)
if(FINISH[i]==FALSE)
{
printf("\n");
printf("系统不安全!!! 本次资源申请不成功!!!\n");
printf("\n");
return 1;
}
}
printf("\n");
printf("经安全性检查，系统安全，本次分配成功。\n");
printf("\n");
printf(" 本次安全序列：");
for(i=0;i<M;i++){
printf("进程");
printf("%d",temp[i]);
printf("->");
}
printf("\n");
return 0;
}
