public void initialize(List <MemorySlot> free_slots)
{
processes = new List <Process>();
freeSlots = new List <MemorySlot>();
allocatedSlots = new List <MemorySlot>();
free_slots.Sort();
int lastAddress = 0;
foreach (MemorySlot slot in free_slots)
{
if (slot.start > lastAddress)
{
Process process = new Process("Allocated", slot.start - lastAddress);
MemorySlot newSlot = new MemorySlot(lastAddress, slot.start - lastAddress, process);
addSlot(newSlot, allocatedSlots);
processes.Add(process);
}
addFreeSlot(slot);
lastAddress = slot.start + slot.size;
}
if (memorySize - lastAddress > 0)
{
Process process = new Process("Allocated", memorySize - lastAddress);
MemorySlot newSlot = new MemorySlot(lastAddress, memorySize - lastAddress, process);
addSlot(newSlot, allocatedSlots);
processes.Add(process);
}
}
public bool allocate(String name, int size)
{
MemorySlot freeSlot = findSlot(size);
if (freeSlot != null)
{
int allocationStart = freeSlot.start;
int remainingSize = freeSlot.size - size;
int remainingStart = freeSlot.start + size;
removeSlot(freeSlot, freeSlots);
if (remainingSize > 0)
{
addFreeSlot(new MemorySlot(remainingStart, remainingSize));
}
Process process = new Process(name, size);
addSlot(new MemorySlot(allocationStart, size, process), allocatedSlots);
processes.Add(process);
return(true);
}
return(false);
}
private MemorySlot mergeSlots(MemorySlot slot1, MemorySlot slot2)
{
int start1 = slot1.start;
int end1 = slot1.start + slot1.size;
int start2 = slot2.start;
int end2 = slot2.start + slot2.size;
if (start1 > start2)
{
int tmp;
tmp = start2;
start2 = start1;
start1 = tmp;
tmp = end1;
end1 = end2;
end2 = tmp;
}
if (start2 > end1)
{
return(null);
}
int start = start1;
int end = end1 > end2 ? end1 : end2;
return(new MemorySlot(start, end - start));
}
private bool isBetter(MemorySlot s1, MemorySlot s2, int algorithm)
{
if (algorithm == FIRST_FIT)
{
return(s1.start < s2.start);
}
else if (algorithm == BEST_FIT)
{
return(s1.size < s2.size);
}
else if (algorithm == WORST_FIT)
{
return(s1.size > s2.size);
}
return(false);
}
private void button_add_Click(object sender, EventArgs e)
{
int start = int.Parse(textBox_start.Text);
int size = int.Parse(textBox_size.Text);
int end = start + size;
MemorySlot slot = new MemorySlot(start, size);
holes.Add(slot);
listBox_holes.Items.Add(slot);
button_Initialize.Enabled = listBox_holes.Items.Count != 0;
textBox_start.Text = end.ToString();
if (end > int.Parse(textBox_memorySize.Text))
{
textBox_memorySize.Text = end.ToString();
}
}
public void addSlot(MemorySlot slot, List <MemorySlot> slots)
{
if (slots.Count == 0)
{
slots.Add(slot);
}
else
{
for (int i = 0; i < slots.Count; i++)
{
if (isBetter(slot, slots[i], algorithm))
{
slots.Insert(i, slot);
return;
}
}
slots.Add(slot);
}
}
public void deallocate(Process process)
{
//Process process = processes[index];
MemorySlot allocatedSlot = null;
foreach (MemorySlot slot in allocatedSlots)
{
if (slot.process == process)
{
allocatedSlot = slot;
break;
}
}
removeSlot(allocatedSlot, allocatedSlots);
MemorySlot freeSlot = new MemorySlot(allocatedSlot.start, allocatedSlot.size);
addFreeSlot(freeSlot);
processes.Remove(process);
}
private void addFreeSlot(MemorySlot slot)
{
addSlot(slot, freeSlots);
List <MemorySlot> mergingList = new List <MemorySlot>();
// Search for mergable slots
foreach (MemorySlot s in freeSlots)
{
if (mergeSlots(slot, s) != null)
{
mergingList.Add(s);
}
}
foreach (MemorySlot s in mergingList)
{
slot = mergeSlots(slot, s);
removeSlot(s, freeSlots);
}
addSlot(slot, freeSlots);
}
private void DrawSlot(Graphics g, Panel panel, MemorySlot slot, int memorySize, Color color)
{
int startAddress = slot.start;
int endAddress = slot.start + slot.size;
string slotText = "Free";
if (slot.process != null)
{
slotText = slot.process.name;
}
slotText = slotText + " - " + slot.size.ToString() + " B";
Pen pen = new Pen(Color.Black, 2);
SolidBrush textBrush = new SolidBrush(Color.FromArgb(255 - color.R, 255 - color.G, 255 - color.B));
SolidBrush addressBrush = new SolidBrush(Color.Black);
StringFormat sf = new StringFormat();
sf.FormatFlags = StringFormatFlags.DirectionRightToLeft;
int VMargin = 10;
int totalHeight = panel.Height - VMargin * 2;
int slotWidth = panel.Width * 60 / 100;
int slotHeight = totalHeight * (endAddress - startAddress) / memorySize;
Point leftTop = new Point(panel.Width * 5 / 100, VMargin + totalHeight * startAddress / memorySize);
Point leftBottom = new Point(leftTop.X, leftTop.Y + slotHeight);
Point rightBottom = new Point(leftTop.X + slotWidth, leftTop.Y + slotHeight);
Point rightTop = new Point(leftTop.X + slotWidth, leftTop.Y);
Point centerPoint = new Point(leftTop.X + slotWidth / 2, leftTop.Y + slotHeight / 2);
Point slotTextPosition = centerPoint;
Point addressPosition = new Point(rightBottom.X + 10, rightBottom.Y - 10);
// Draw slot borders
g.DrawLine(pen, leftTop, leftBottom);
g.DrawLine(pen, rightTop, rightBottom);
g.DrawLine(pen, leftTop, rightTop);
g.DrawLine(pen, leftBottom, rightBottom);
// Fill slot background
g.FillRectangle(new SolidBrush(color), leftTop.X, leftTop.Y, slotWidth, slotHeight);
// Print process name
if (slotHeight > 16)
{
slotTextPosition.X += slotText.Count() * 6 / 2;
slotTextPosition.Y -= 8;
g.DrawString(slotText, this.Font, textBrush, slotTextPosition, sf);
}
// Print address label
String addressText = "0x" + endAddress.ToString("X");
if (slotHeight > 8)
{
addressPosition.X += addressText.Count() * 6;
g.DrawString(addressText, this.Font, addressBrush, addressPosition, sf);
}
}
public void removeSlot(MemorySlot slot, List <MemorySlot> slots)
{
slots.Remove(slot);
}
