IMPLEMENTATION OF FILE ALLOCATION STRATEGIES

PROGRAM CODING to implement File allocation
#include<stdio.h>
#include<stdlib.h>
struct list
{
 int datano;
 char *name;
 struct list *next;
 }*hf,*lf,*ha[10],*la[10];
int m,n;
int size;


struct file
{
 char name[20];
 int size;
 int nob;
 }f[10];


struct index
{
 int datano;
 char *name;
 struct list **link;
 struct index *next;
}*h,*l;


int a[200],g=0;


void createfree()
{
 int i;
 hf=(struct list*)malloc(sizeof(struct list));
 hf->next=NULL;
 for(i=1;i<=m;i++)
 {
  struct list*node=(struct list*)malloc(sizeof(struct list));
  node->datano=i;
  node->name=NULL;
  node->next=NULL;
  if(i==1)
  hf->next=node;
  else
  lf->next=node;
  lf=node;
  
 }
 }


  void createind()
{
 int i;
 h=(struct index*)malloc(sizeof(struct index));
 h->next=NULL;
 for(i=0;i<n;i++)
 {
  struct index *node=(struct index*)malloc(sizeof(struct index));
  node->datano=i;
  node->name=NULL;
  node->next=NULL;
  node->link=NULL;
  if(i==0)
  h->next=node;
  else
  l->next=node;
l=node;
 }
}

void read()
{
 int i;
 printf("\nEnter the no of blocks in the disk:--\n");
 scanf("%d",&m);
 printf("\nEnter the size of each block:--\n");
 scanf("%d",&size);
 printf("\nEnter the number of files:--\n"); 
 scanf("%d",&n);
 for(i=0;i<n;i++)
 {
  printf("\nEnter the file of %d name:--",i+1);
  scanf("%s",f[i].name);
  printf("\nEnter the size of file %d:--",i+1);
  scanf("%d",&f[i].size);
  if(f[i].size%size==0)
  f[i].nob=f[i].size/size;
  else
  f[i].nob=f[i].size/size+1;
  }
}


void gen(int z)
{
 int i=0,r,j;
 srand(z);
 for(i=0;i<200;i++)
 {
  r=(rand()%200+1);
  for(j=0;j<i;j++)
  if(r==a[j])
  break;
  if(j==i)
  {
    a[i]=r;
  }
 else
 i--;
 } 
}




void contiguous()
{
 int i,j,g=1;
 struct list *temp;
 for(i=0;i<n;i++)
 {
  ha[i]=(struct list*)malloc(sizeof(struct list));
  for(j=0;j<f[i].nob;j++)
  {
   struct list *node=(struct list*)malloc(sizeof(struct list));
   node->datano=g;
   g++;
   node->name=f[i].name;
   node->next=NULL;
   if(j==0)
    ha[i]->next=node;
    else
    la[i]->next=node;
    la[i]=node;
  }
  }
temp=hf;
for(i=0;i<g;i++)
temp=temp->next;
hf->next=temp;
}


void dele(int r)
{
struct list *t;
for(t=hf;t!=NULL;t=t->next)
if(t->next->datano==r)
{
t->next=t->next->next;
break;
}
}


void linked()
{
int r=1,i,j,k=0;
struct list *t;
for(i=0;i<n;i++)
{
ha[i]=(struct list*)malloc(sizeof(struct list));
for(j=0;j<f[i].nob;j++)
{
r=a[k];
k++;
dele(r);
struct list *node=(struct list*)malloc(sizeof(struct list));
node->datano=r;
node->name=f[i].name;
node->next=NULL;
if(j==0)
ha[i]->next=node;
else
la[i]->next=node;
la[i]=node;
}
}
}


void indexed()
{
 int r=1,i,j,k=0;
 struct index *t;
 for(i=0;i<n;i++)
 {
   ha[i]=(struct list*)malloc(sizeof(struct list));
   for(j=0;j<f[i].nob;j++)
   {
     a:
     r=a[k];
     k++;
     if(r<(n+1))
     goto a;


     dele(r);
     struct list*node=(struct list*)malloc(sizeof(struct list));
     node->datano=r;
     node->name=f[i].name;
     node->next=NULL;
     if(j==0)
     ha[i]->next=node;
     else
     la[i]->next=node;
     la[i]=node;
  }
}
 t=h->next;
 for(i=0;i<n;i++)
 {
   t->name=f[i].name;
   t->datano=i+1;
   t->link=&ha[i];
   t=t->next;
   }
}


void contdis()
{
int i;
printf("\n\n\t Filename\t start\t Length\n");
for(i=0;i<n;i++)
{
printf("\t\t%s\t",f[i].name);
printf("\t%d\t\t",ha[i]->next->datano);
printf("%d\n",f[i].nob);
}
}


void linkdis()
{
int i,j;
printf("\n\n\t Filename\t start\t End\n");
for(i=0;i<n;i++)
{
printf("\t\t%s\t\t",f[i].name);
printf("%d\t",ha[i]->next->datano);
printf("%d\n",la[i]->datano);
}


struct list *t;
printf("\n\n INDIVIDUAL FILE LISTING:-");
printf("\n\t Filename \t datablocks\n");


for(i=0;i<n;i++)
{
printf("\n%s",f[i].name);
for(t=ha[i]->next;t!=NULL;t=t->next)
{
printf("-->%d",t->datano);
}
}
}


void indexdis()
{
int i;
struct index *temp;
temp=h->next;
printf("\n\t FILE NAME \t BLOCK INDEXED\n");
for(i=0;i<n;i++)
{
printf("\t\t%s",f[i].name);
printf("\t\t\t%d\n",temp->datano);
temp=temp->next;
}
struct list *t;
printf("\n\n INDEX TABLE LISTING:-");
printf("\n FILENAME  INDEXED BLOCK");
for(i=0;i<n;i++)
{
printf("\n%s  \n",f[i].name);
for(t=ha[i]->next;t!=NULL;t=t->next)
printf("\t\t%d\n",t->datano);
}
}


int main()
{
int z,ch;
read();
createfree();
gen(z);


do
{
printf("\n\tFILE ALLOCATION TECHNIQUES\n1.CONTIGUOUS\n2.LINKED\n3.INDEXED\n4.EXIT\n\tEnter your choice:-");
scanf("%d",&ch);
switch(ch)
{


case 1:
contiguous();
contdis();
createfree();
break;


case 2:
gen(z);
z++;
linked();
linkdis();
createfree();
break;


case 3:
gen(z);
z++;
createind();
indexed();
indexdis();
createfree();
break;


case 4:
exit(1);


}
}while(ch!=4);
}