private long CollectStatistic(HashPage pg, HashStatistic stat, int height)
{
long totalHeight = 0;
stat.nPages += 1;
if (++height > stat.maxHeight)
{
stat.maxHeight = height;
}
foreach (object child in pg.items)
{
if (child is HashPage)
{
totalHeight += CollectStatistic((HashPage)child, stat, height);
}
else if (child != null)
{
int collisionChainLength = 0;
for (CollisionItem item = (CollisionItem)child; item != null; item = item.next)
{
collisionChainLength += 1;
}
if (stat.maxCollisionChainLength < collisionChainLength)
{
stat.maxCollisionChainLength = collisionChainLength;
}
stat.nItems += collisionChainLength;
stat.nChains += 1;
totalHeight += height;
}
}
return(totalHeight);
}
public override void Clear()
#endif
{
if (root != null)
{
root.Deallocate();
root = null;
nElems = 0;
Modify();
}
}
public void Remove(object key)
#endif
{
HashPage pg = root;
if (pg != null)
{
uint divisor = 1;
int hashCode = key.GetHashCode();
while (true)
{
int h = (int)((uint)hashCode / divisor % pageSize);
object child = pg.items[h];
if (child is HashPage)
{
pg = (HashPage)child;
divisor *= pageSize;
}
else
{
CollisionItem prev = null;
for (CollisionItem item = (CollisionItem)child; item != null; item = item.next)
{
if (item.hashCode == hashCode && item.key.Equals(key))
{
if (prev != null)
{
prev.next = item.next;
prev.Modify();
}
else
{
pg.items[h] = item.next;
pg.Modify();
}
nElems -= 1;
Modify();
#if USE_GENERICS
return(true);
#else
return;
#endif
}
prev = item;
}
break;
}
}
}
#if USE_GENERICS
return(false);
#endif
}
public void Reset()
{
currItem = null;
nextItem = null;
stack.Clear();
HashPage pg = hash.root;
if (pg != null)
{
int start = 0;
int sp = 0;
DepthFirst:
while (true)
{
for (int i = start; i < pg.items.Count; i++)
{
object child = pg.items[i];
if (child != null)
{
stack.Add(new StackElem(pg, i));
sp += 1;
if (child is HashPage)
{
pg = (HashPage)child;
start = 0;
goto DepthFirst;
}
else
{
nextItem = (CollisionItem)child;
return;
}
}
}
if (sp != 0)
{
StackElem top = (StackElem)stack[--sp];
stack.RemoveAt(sp);
pg = top.page;
start = top.pos + 1;
}
else
{
break;
}
}
}
}
public bool MoveNext()
{
if (nextItem != null)
{
currItem = nextItem;
if ((nextItem = nextItem.next) == null)
{
int sp = stack.Count;
do
{
StackElem top = (StackElem)stack[--sp];
stack.RemoveAt(sp);
HashPage pg = top.page;
int start = top.pos + 1;
DepthFirst:
while (true)
{
for (int i = start; i < pg.items.Count; i++)
{
object child = pg.items[i];
if (child != null)
{
stack.Add(new StackElem(pg, i));
sp += 1;
if (child is HashPage)
{
pg = (HashPage)child;
start = 0;
goto DepthFirst;
}
else
{
nextItem = (CollisionItem)child;
return(true);
}
}
}
break;
}
} while (sp != 0);
}
return(true);
}
return(false);
}
public bool TryGetValue(object key, out object val)
#endif
{
HashPage pg = root;
if (pg != null)
{
uint divisor = 1;
int hashCode = key.GetHashCode();
while (true)
{
int h = (int)((uint)hashCode / divisor % pageSize);
object child = pg.items[h];
if (child is HashPage)
{
pg = (HashPage)child;
divisor *= pageSize;
}
else
{
for (CollisionItem item = (CollisionItem)child; item != null; item = item.next)
{
if (item.hashCode == hashCode && item.key.Equals(key))
{
#if USE_GENERICS
val = (V)item.obj;
#else
val = item.obj;
#endif
return(true);
}
}
break;
}
}
}
val = null;
return(false);
}
internal StackElem(HashPage page, int pos)
{
this.page = page;
this.pos = pos;
}
public void Set(object key, object obj)
{
int hashCode = key.GetHashCode();
HashPage pg = root;
if (pg == null)
{
pg = new HashPage(Storage, pageSize);
int h = (int)((uint)hashCode % pageSize);
pg.items[h] = new CollisionItem(key, obj, hashCode);
root = pg;
nElems = 1;
Modify();
}
else
{
uint divisor = 1;
while (true)
{
int h = (int)((uint)hashCode / divisor % pageSize);
object child = pg.items[h];
if (child is HashPage)
{
pg = (HashPage)child;
divisor *= pageSize;
}
else
{
CollisionItem prev = null;
CollisionItem last = null;
int collisionChainLength = 0;
for (CollisionItem item = (CollisionItem)child; item != null; item = item.next)
{
if (item.hashCode == hashCode)
{
if (item.key.Equals(key))
{
item.obj = obj;
item.Modify();
return;
}
if (prev == null || prev.hashCode != hashCode)
{
collisionChainLength += 1;
}
prev = item;
}
else
{
collisionChainLength += 1;
}
last = item;
}
if (prev == null || prev.hashCode != hashCode)
{
collisionChainLength += 1;
}
if (collisionChainLength > loadFactor)
{
HashPage newPage = new HashPage(Storage, pageSize);
divisor *= pageSize;
CollisionItem next;
for (CollisionItem item = (CollisionItem)child; item != null; item = next)
{
next = item.next;
int hc = (int)((uint)item.hashCode / divisor % pageSize);
item.next = (CollisionItem)newPage.items[hc];
newPage.items[hc] = item;
item.Modify();
}
pg.items[h] = newPage;
pg.Modify();
pg = newPage;
}
else
{
CollisionItem newItem = new CollisionItem(key, obj, hashCode);
if (prev == null)
{
prev = last;
}
if (prev != null)
{
newItem.next = prev.next;
prev.next = newItem;
prev.Modify();
}
else
{
pg.items[h] = newItem;
pg.Modify();
}
nElems += 1;
Modify();
return;
}
}
}
}
}
