/*------------------------------------------------------------------------
* University: UESTC
* Student: 鲁立虹
* Number: 2406202002
* Create Date: 2007-6-21
* Program Name: deadLock
* Description: deadLock Algorithm.
*
*------------------------------------------------------------------------
*/
# <stdio.h>
# M 3 //资源种类数
# N 4 //进程数
reg[N],r1[N];
count,c;
/*------------------------------------------------------------------------
*画线
*------------------------------------------------------------------------
*/
void line{
prf("------------------------------------------------------------------------\n");
}
/*------------------------------------------------------------------------
*输入各数据,max,alloc,res
*------------------------------------------------------------------------
*/
void input( max[N] , alloc[N], res){ i,j;
//输入各资源数目
prf("Enter the amount of each res:\n");
for(i=0; i<M; i)
scanf("%d",&res );
line;
//输入各进程需求各资源最大数
prf("Enter the biggest number of each res that each process want:\n");
for(i=0; i<N; i)
for(j=0; j<M; j)
scanf("%d",&max [j]);
line;
//输入各进程已经得到资源数
prf("Enter the number of each res that each process get:\n");
for(i=0; i<N; i)
for(j=0; j<M; j)
scanf("%d",&alloc [j]);
line;
}
/*------------------------------------------------------------------------
*计算数据ar
*------------------------------------------------------------------------
*/
void cal( max[N] , alloc[N], res, ar){ i,j;
pr ={M*0}; //进程占有各资源数 //计算pr
for(i=0; i<N; i)
for(j=0; j<M; j)
pr[j] alloc [j];
//计算ar
for(i=0; i<M; i)
ar = res - pr ;
}
/*------------------------------------------------------------------------
*显示进程资源状态
*------------------------------------------------------------------------
*/
void show( max[N] , alloc[N], ar){ i,j;
prf("Available Res:\n");
prf("R1\tR2\tR3\t\n");
for(i=0; i<M; i)
prf("%d\t",ar );
prf("\n");
line;
prf("\t\tMax\t\t|\tAllocation\n");
prf("\tR1\tR2\tR3\t|\tR1\tR2\tR3\n");
for(i=0; i<N; i){
prf("P%d\t",i+1);
for(j=0; j<M; j)
prf("%d\t",max [j]);
prf("|\t");
for(j=0; j<M; j)
prf("%d\t",alloc [j]);
prf("\n");
}
}
/*------------------------------------------------------------------------
* a<b?1:0
*------------------------------------------------------------------------
*/
small( a , b){ i,sign;

sign = 0;
for(i=0; i<M; i)
(a <=b )
sign;
(sign M) 1;
0;
}
/*------------------------------------------------------------------------
*在reg中搜索dig,有返回1无返回0
*------------------------------------------------------------------------
*/
look( reg[N], dig){
i;
sign;
sign = 0;
for(i=0; i<N; i)
(reg dig)
sign;
(!sign)
0;

1;
}
/*------------------------------------------------------------------------
*检查计算机系统是否安全,如果安全返回1不安全返回0
*------------------------------------------------------------------------
*/
safe( max[N] , alloc[N], ar){ i,j;
sign;
need[N] ; //need [j],进程Pi需要资源Rj数 temp ;
sign = 0;
for(i=0; i<N; i)
for(j=0; j<M; j)
need [j] = max [j] - alloc [j];
(c < N)
for(i=0; i<N; i){
(!look(r1,i))
(small(need ,ar)){
r1[c] = i;
for(j=0; j<M; j)
temp[j] = alloc [j]+ar[j];
sign = safe(max,alloc,temp);
(sign)
reg[count] = i;

r1[--c] = -1;
}
}

for(i=0; i<N; i){
(!look(reg,i))
(small(need ,ar)){
reg[count] = i;
sign = 1;
}
}
sign;
}
/*------------------------------------------------------------------------
*检查安全
*------------------------------------------------------------------------
*/
checkSafe( max[N] , alloc[N], ar){ i;
sign;

count = 0;
c = 0;
for(i=0; i<N; i){
reg = -1;
r1 = -1;
}

sign = safe(max,alloc,ar);

(sign){
prf("The system is safe.\n");
prf("The safe route:");
for(i=N-1; i>0; i--)
prf("P%d->",reg +1);
prf("P%d\n",reg +1);
line;
1;
}

{
prf("The system is unsafe. Input again.\n");
line;
0;
}
}
/*------------------------------------------------------------------------
*
*------------------------------------------------------------------------
*/
{
i,j;
p;
sign;
max[N] ; //max [j],进程Pi需要资源Rj最大数 alloc[N] ; //alloc [j],进程Pi已得到资源Rj数 alloc1[N] ; res ; //各资源数目 ar ; //系统现有各资源数 ar1 ; request ; //某进程请求资源数
do{
input(max,alloc,res); //输入各数据
cal(max,alloc,res,ar); //计算need,ar
show(max,alloc,ar); //显示进程资源状态
sign = checkSafe(max,alloc,ar); //检查安全
}while(!sign);

//输入发出请求进程号,请求资源
prf("P request R, Enter the process and each res, then check it.\n");
prf("If you want to end, evaluate P=0\n");
for( ; ; ){
line;
for(i=0; i<N; i)
for(j=0; j<M; j)
alloc1 [j] = alloc [j];
prf("Enter P(1-%d):",N);
scanf("%d",&p);
(!p) ;
prf("Enter request res:");
for(i=0; i<M; i)
scanf("%d",&request );
(small(request,ar)){
for(i=0; i<M; i){
alloc1[p-1] = request + alloc1[p-1] ;
ar1 = ar - request ;
}
sign = checkSafe(max,alloc1,ar1);
(sign){
prf("Request Successfully. After requesting:\n");
show(max,alloc1,ar1);
}
}

prf("Unsuccessfully request.");
}
}