static inline void segmentalloc(int total_size, int request) {
int i, flevel = 0, size = total_size;
if (total_size < request) {
puts(" * Result:");
puts(" * The system don't have enough free memory");
puts(" * Suggession : Go for VIRTUAL MEMORY");
return;
}
while (1) {
if (request <= size && div2(size) < request) {
break;
} else {
size = div2(size);
flevel++;
}
}
for (i = power_2(flevel) - 1; i <= (power_2(flevel + 1) - 2); i++) {
if (tree[i] == 0 && place(i)) {
tree[i] = request;
makedivided(i);
puts(" * Result : Successful Allocation");
break;
}
}
if (i == power_2(flevel + 1) - 1) {
puts(" * Result :");
puts(" * The system don't have enough free memory");
puts(" * Suggession : Go for VIRTUAL Memory Mode");
}
}
int segmentalloc(int totalsize,int request)
{
#ifdef DEBUG
printf("\n Inside the allocation routine:\n");
#endif
flevel=0; //everytime I come to allocation I reset flevel to 0
if(request>totalsize)
{
//check if requested size > total size
printf(" * Requesting more than total memory ??? \n");
printf(" * Requested memory size= %d,total memory size=%d ", request,totalsize);
printf("\n Press a key to continue...");
getchar();
return 0; // Should I return 0 here ?
}
// DEBUG let us see the array at beginning
while(1) // This infinite loop is safe as we have already checked requesd size vs total size
{
#ifdef DEBUG
printf("Requested memory size= %d, current memory block size being examined=%d ", request,totalsize);
#endif
if((request<=totalsize) && (request>(totalsize/2)))
break; // found the right buddy level to check the availability of memory
else
{
#ifdef DEBUG
printf("\n Not yet found the right block; tree level=%d ; current memory block is : %d \n",flevel,totalsize);
#endif
//go dividing till you reach the right level
totalsize/=2;
flevel++;
}
} //end of while
#ifdef DEBUG
printf("\n correct tree level found=%d ; memory block to be allocated is : %d \n",flevel,totalsize);
#endif
// Check at level=flevel of the tree from left to right to see where the match is happening
for(i=power(2,flevel)-1;i<=(power(2,flevel+1)-2);i++) // this formula is corrected provided root node =0
{
#ifdef DEBUG
printf("DEBG : In allocation : value of i=%d\n",i);
#endif
if(tree[i]==0 ) // && place(i) same thing ?? place(i) will return 1 if available
{
// I am storing block which is allocated
incrementNode();
tree[i]=totalsize;
//this is also the place to record the no of nodes that are allocated at a tree level
incrementArray(total_level_alloc,flevel);
#ifdef DEBUG
printf("\n DBG: allocated ; flevel= %d, current value=%d",flevel,total_level_alloc[flevel]);
#endif
makedivided(i); // without this, the allocation will NOT show
printf(" \n ......Successful Allocation.......... \n");
break;
}
//Here it comes out at least once after exhausting this loop
if(i==power(2,flevel+1)-1) // first element in the next level
{
printf(" Result : ");
printf("* NOT enough free memory\n");
totalsize=0;
}
} //end of for
#ifdef DEBUG
debug_print();
#endif
return totalsize; // return the value that has been successfully allocated
}
