/**********************************************************************
*********************************************************************/
async void B_Start_Clicked(object sender, EventArgs e)
{
BuddySystem.endProcess = false;
//check if there was a vailid input
if (e_ProcessSize.Text != null && ValidateMemoryRequestInput())
{
bool bfound = BuddySystem.AllocateBlock(Int32.Parse(e_ProcessSize.Text), p_ProcessNames.SelectedItem.ToString());
//if fitting blocksize was found
if (bfound)
{
BuddySystem.availableProcesses.Remove(p_ProcessNames.SelectedItem.ToString());
BuddySystem.activeProcesses.Add(p_ProcessNames.SelectedItem.ToString());
await Navigation.PopModalAsync(); // close Modal
}
else
{
await DisplayAlert("Alert", "Process doesn't fit in memory", "OK");
await Navigation.PopModalAsync(); // close Modal
}
}
else if (e_ProcessSize.Text == null)
{
await DisplayAlert("Alert", "Please enter a process size", "OK");
}
else if (!ValidateMemoryRequestInput())
{
await DisplayAlert("Alert", "Please enter a valid process size (only integers >= " + minimumProcessSize + ")", "OK");
}
}
/**********************************************************************
*********************************************************************/
async void B_End_Clicked(object sender, EventArgs e)
{
BuddySystem.endProcess = true;
BuddySystem.activeProcesses.Remove(p_ProcessNames.SelectedItem.ToString());
BuddySystem.availableProcesses.Add(p_ProcessNames.SelectedItem.ToString());
BuddySystem.DeallocateBlock(p_ProcessNames.SelectedItem.ToString());
await Navigation.PopModalAsync(); // close Modal
}
//METHODS
/**********************************************************************
*********************************************************************/
//checks if there is a block, in which the process could possibly fit in
public static bool AllocateBlock(int processSize, String processName)
{
currentProcess = processName;
//find the fitting block size
int blockSize = BuddySystem.FindFittingBlockSize(processSize); //is 0 when process is bigger than the whole memory
//does such a block exist? or a bigger one?
int block = (int)absoluteMemorySize + 1; //bigger than all blocks ever available
int index = -1;
//find the block clostest(and still bigger) to requested blocksize
for (int i = 0; i < buddySystem.Count; i++)
{
int dummy = buddySystem[i].GetBlockSize();
if (dummy >= blockSize && dummy < block && buddySystem[i].GetFree())
{
block = dummy;
index = i;
}
}
//process bigger than memory or a blog with fitting size doesn't exist
if (index == -1 || blockSize == 0)
{
return(false);
}
//block fits perfectly
if (block == blockSize && buddySystem[index].GetFree())
{
buddySystem[index].OccupyBlock(processName, processSize);
AddBuddySystemCell();
b_Restart.IsEnabled = true;
return(true);
}
//blocksize found but has to be split
if (block > blockSize && buddySystem[index].GetFree())
{
SplitBlock(index, blockSize);
buddySystem[index].OccupyBlock(processName, processSize);
AddBuddySystemCell();
b_Restart.IsEnabled = true;
return(true);
}
return(false);
}
