/* 本程序包括:死锁检测算法
VC++调试通过
#include<stdio.h>
#include<iostream.h>
#include<string.h>
const int MAXQUEUE=100; //定义表的最大行数
typedef struct node{
int resource;
int process;
}cell;
cell occupy[MAXQUEUE];
int occupy_quantity;
cell wait[MAXQUEUE];
int wait_quantity;
//初始化函数
void initial()
{
int i;
for(i=0;i<MAXQUEUE;i++){
occupy[i].process=-1;
occupy[i].resource=-1;
wait[i].process=-1;
wait[i].resource=-1;
}
occupy_quantity=0;
wait_quantity=0;
}
//读数据文件
int readData()
{
FILE *fp;
char fname[20];
int i;
cout<<"请输入资源分配表文件的文件名:"<<endl;
strcpy(fname,"10trouble1.txt");
//cin>>fname;
if((fp=fopen(fname,"r"))==NULL){
cout<<"错误,文件打不开,请检查文件名:)"<<endl;
return 0;
}
else{
while(!feof(fp)){
fscanf(fp,"%d %d",&occupy[occupy_quantity].resource,&occupy[occupy_quantity].process);
occupy_quantity++;
}
}
cout<<"请输入进程等待表文件的文件名:"<<endl;
strcpy(fname,"10trouble2.txt");
//cin>>fname;
if((fp=fopen(fname,"r"))==NULL){
cout<<"错误,文件打不开,请检查文件名:)"<<endl;
return 0;
}
else{
while(!feof(fp)){
fscanf(fp,"%d %d",&wait[wait_quantity].process,&wait[wait_quantity].resource);
wait_quantity++;
}
}
//输出所读入的数据
cout<<endl<<endl<<"输出所读入的数据"<<endl;
cout<<"━━━━━━━━━━━━━━━━━━━━━━━"<<endl;
cout<<"资源分配表"<<endl;
cout<<"资源编号 进程编号"<<endl;
for(i=0;i<occupy_quantity;i++){
cout<<" "<<occupy[i].resource<<" "<<occupy[i].process<<endl;
}
cout<<"───────────────────────"<<endl;
cout<<"进程等待表"<<endl;
cout<<"进程编号 资源编号"<<endl;
for(i=0;i<wait_quantity;i++){
cout<<" "<<wait[i].resource<<" "<<wait[i].process<<endl;
}
return 1;
}
//检测
void check()
{
int table[MAXQUEUE][MAXQUEUE];
int table1[MAXQUEUE][MAXQUEUE];
int i,j,k;
int flag,t,p;
int max_process;
//初始化表格
for(i=0;i<MAXQUEUE;i++){
for(j=0;j<MAXQUEUE;j++){
table[i][j]=0;
table1[i][j]=0;
}
}
//先找到进程最大编号
max_process=-1;
for(i=0;i<occupy_quantity;i++){
if(occupy[i].process>max_process){
max_process=occupy[i].process;
}
}
for(i=0;i<wait_quantity;i++){
if(wait[i].process>max_process){
max_process=wait[i].process;
}
}
for(i=0;i<wait_quantity;i++){
for(j=0;j<occupy_quantity;j++){
if(wait[i].resource==occupy[j].resource){
table[wait[i].process][occupy[j].process]=1;
table1[wait[i].process][occupy[j].process]=1;
}
}
}
cout<<"初始等待占用表:"<<endl;
for(i=0;i<max_process+1;i++){
for(j=0;j<max_process+1;j++){
cout<<table[i][j]<<" ";
}
cout<<endl;
}
cout<<endl;
for(i=0;i<max_process+1;i++){
for(j=0;j<max_process+1;j++){
for(k=0;k<max_process+1;k++){
table[i][j]=table[i][j]||(table[i][k]&&table[k][j]);
}
}
}
cout<<"检测后的等待占用表:"<<endl;
for(i=0;i<max_process+1;i++){
for(j=0;j<max_process+1;j++){
cout<<table[i][j]<<" ";
}
cout<<endl;
}
flag=-1;
for(i=0;i<max_process+1;i++){
if(table[i][i]==1){
flag=i;
break;
}
}
cout<<endl<<endl<<"检测结果"<<endl;
cout<<"───────────────────"<<endl;
if(flag!=-1){
cout<<"存在死锁"<<endl;
cout<<"进程循环等待队列:";
p=flag; //存在进程循环等待队列的那一进程
//进程循环等待队列中的所有进程是table表中的这一行是1的进程,只是顺序要再确定
t=1;
while(t){
cout<<p<<" ";
for(j=0;j<max_process+1;j++){
if(table1[p][j]==1){
if(table[j][flag]==1){
p=j;
break;
}
}
}
if(p==flag)t=0;
}
cout<<flag<<endl;
}
else{
cout<<"不存在死锁"<<endl;
}
}
//显示版权信息函数
void version()
{
cout<<endl<<endl;
cout<<" ┏━━━━━━━━━━━━━━━━━━━━━━━┓"<<endl;
cout<<" ┃ 死 锁 检 测 算 法 ┃"<<endl;
cout<<" ┠───────────────────────┨"<<endl;
cout<<" ┃ (c)All Right Reserved Neo ┃"<<endl;
cout<<" ┃ sony006@163.com ┃"<<endl;
cout<<" ┃ version 2004 build 1122 ┃"<<endl;
cout<<" ┗━━━━━━━━━━━━━━━━━━━━━━━┛"<<endl;
cout<<endl<<endl;
}
void main()
{
int flag;
version();
initial();
flag=readData();
if(flag)check();
}
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