//
// New processes are allocated memory in the main_memory array.
//
void memory_allocate(PCB new_arrival)
{
int PID = new_arrival.get_id();
int requested_memory = new_arrival.get_size();
int free_memory = 0;
while(main_memory[free_memory] != 0)
free_memory++;
if((MEM_SIZE - free_memory) >= requested_memory)
for(int i = free_memory; i < free_memory + requested_memory; i++)
main_memory[i] = PID;
else
{
if (DEBUG) cout << "(memory_allocate): ERROR Not enough memory for process " << PID << endl;
}
// Memory has been allocated, update UI.
state_changed_flag = true;
}
//
// Processes that are finished running have their memory removed.
// Remaining memory is then shifted down.
//
void memory_deallocate(PCB finished_process)
{
int i = 0;
int j;
int PID = finished_process.get_id();
while(main_memory[i] != PID)
i++;
j = i;
while(main_memory[j] == PID)
{
main_memory[j] = 0;
j++;
}
while(main_memory[j] != 0 && j < MEM_SIZE)
{
main_memory[i] = main_memory[j];
main_memory[j] = 0;
i++;
j++;
}
// Memory has been deallocated, update UI.
state_changed_flag = true;
}