Banker's Algorithm in C

#include<stdio.h> #include<stdlib.h>

void print(int x[][10],int n,int m){ int i,j; for(i=0;i<n;i++){ printf("\n"); for(j=0;j<m;j++){ printf("%d\t",x[i][j]); } } }

//Resource Request algorithm void res_request(int A[10][10],int N[10][10],int AV[10][10],int pid,int m) { int reqmat[1][10]; int i; printf("\n Enter additional request :- \n"); for(i=0;i<m;i++){ printf(" Request for resource %d : ",i+1); scanf("%d",&reqmat[0][i]); }

for(i=0;i<m;i++)
	if(reqmat[0][i] > N[pid][i]){
		printf("\n Error encountered.\n");
		exit(0);
}

for(i=0;i<m;i++)
	if(reqmat[0][i] > AV[0][i]){
		printf("\n Resources unavailable.\n");
		exit(0);
	}

for(i=0;i<m;i++){
	AV[0][i]-=reqmat[0][i];
	A[pid][i]+=reqmat[0][i];
	N[pid][i]-=reqmat[0][i];
}

}

//Safety algorithm int safety(int A[][10],int N[][10],int AV[1][10],int n,int m,int a[]){

int i,j,k,x=0;
int F[10],W[1][10];
int pflag=0,flag=0;
for(i=0;i<n;i++)
	F[i]=0;
for(i=0;i<m;i++)
	W[0][i]=AV[0][i];

for(k=0;k<n;k++){
	for(i=0;i<n;i++){
		if(F[i] == 0){
			flag=0;
			for(j=0;j<m;j++){
				if(N[i][j] > W[0][j])
					flag=1;
			}
			if(flag == 0 && F[i] == 0){
				for(j=0;j<m;j++)
					W[0][j]+=A[i][j];
				F[i]=1;
				pflag++;
				a[x++]=i;
			}
		}
	}
	if(pflag == n)
		return 1;
}
return 0;

}

//Banker's Algorithm void accept(int A[][10],int N[][10],int M[10][10],int W[1][10],int *n,int *m){ int i,j; printf("\n Enter total no. of processes : "); scanf("%d",n); printf("\n Enter total no. of resources : "); scanf("%d",m); for(i=0;i<*n;i++){ printf("\n Process %d\n",i+1); for(j=0;j<*m;j++){ printf(" Allocation for resource %d : ",j+1); scanf("%d",&A[i][j]); printf(" Maximum for resource %d : ",j+1); scanf("%d",&M[i][j]); } } printf("\n Available resources : \n"); for(i=0;i<*m;i++){ printf(" Resource %d : ",i+1); scanf("%d",&W[0][i]); }

for(i=0;i<*n;i++)
	for(j=0;j<*m;j++)
		N[i][j]=M[i][j]-A[i][j];

printf("\n Allocation Matrix");
print(A,*n,*m);
printf("\n Maximum Requirement Matrix");
print(M,*n,*m);
printf("\n Need Matrix");
print(N,*n,*m);

}

int banker(int A[][10],int N[][10],int W[1][10],int n,int m){ int j,i,a[10]; j=safety(A,N,W,n,m,a); if(j != 0 ){ printf("\n\n"); for(i=0;i<n;i++) printf(" P%d ",a[i]); printf("\n A safety sequence has been detected.\n"); return 1; }else{ printf("\n Deadlock has occured.\n"); return 0; } }

int main(){ int ret; int A[10][10]; int M[10][10]; int N[10][10]; int W[1][10]; int n,m,pid,ch; printf("\n DEADLOCK AVOIDANCE USING BANKER'S ALGORITHM\n"); accept(A,N,M,W,&n,&m); ret=banker(A,N,W,n,m); if(ret !=0 ){ printf("\n Do you want make an additional request ? (1=Yes|0=No)"); scanf("%d",&ch); if(ch == 1){ printf("\n Enter process no. : "); scanf("%d",&pid); res_request(A,N,W,pid-1,m); ret=banker(A,N,W,n,m); if(ret == 0 ) exit(0); } }else exit(0); return 0; }