public FoundPage Find(MemorySlice key)
{
for (int i = 0; i < _cache.Length; i++)
{
var page = _cache[i];
if (page == null)
continue;
var first = page.FirstKey;
var last = page.LastKey;
switch (key.Options)
{
case SliceOptions.BeforeAllKeys:
if (first.Options == SliceOptions.BeforeAllKeys)
return page;
break;
case SliceOptions.AfterAllKeys:
if (last.Options == SliceOptions.AfterAllKeys)
return page;
break;
case SliceOptions.Key:
if ((first.Options != SliceOptions.BeforeAllKeys && key.Compare(first) < 0))
continue;
if (last.Options != SliceOptions.AfterAllKeys && key.Compare(last) > 0)
continue;
return page;
default:
throw new ArgumentException(key.Options.ToString());
}
}
return null;
}
public FoundPage Find(MemorySlice key)
{
int position = current;
int itemsLeft = _cacheSize;
while (itemsLeft > 0)
{
var page = _cache[position % _cacheSize];
if (page == null)
{
itemsLeft--;
position++;
continue;
}
var first = page.FirstKey;
var last = page.LastKey;
switch (key.Options)
{
case SliceOptions.Key:
if ((first.Options != SliceOptions.BeforeAllKeys && key.Compare(first) < 0))
{
break;
}
if (last.Options != SliceOptions.AfterAllKeys && key.Compare(last) > 0)
{
break;
}
return(page);
case SliceOptions.BeforeAllKeys:
if (first.Options == SliceOptions.BeforeAllKeys)
{
return(page);
}
break;
case SliceOptions.AfterAllKeys:
if (last.Options == SliceOptions.AfterAllKeys)
{
return(page);
}
break;
default:
throw new ArgumentException(key.Options.ToString());
}
itemsLeft--;
position++;
}
return(null);
}
public FoundPage Find(MemorySlice key)
{
for (int i = 0; i < _cache.Length; i++)
{
var page = _cache[i];
if (page == null)
{
continue;
}
var first = page.FirstKey;
var last = page.LastKey;
switch (key.Options)
{
case SliceOptions.BeforeAllKeys:
if (first.Options == SliceOptions.BeforeAllKeys)
{
return(page);
}
break;
case SliceOptions.AfterAllKeys:
if (last.Options == SliceOptions.AfterAllKeys)
{
return(page);
}
break;
case SliceOptions.Key:
if ((first.Options != SliceOptions.BeforeAllKeys && key.Compare(first) < 0))
{
continue;
}
if (last.Options != SliceOptions.AfterAllKeys && key.Compare(last) > 0)
{
continue;
}
return(page);
default:
throw new ArgumentException(key.Options.ToString());
}
}
return(null);
}
public FoundPage Find(MemorySlice key)
{
int position = current;
int itemsLeft = _cacheSize;
while ( itemsLeft > 0 )
{
var page = _cache[position % _cacheSize];
if (page == null)
{
itemsLeft--;
position++;
continue;
}
var first = page.FirstKey;
var last = page.LastKey;
switch (key.Options)
{
case SliceOptions.Key:
if ((first.Options != SliceOptions.BeforeAllKeys && key.Compare(first) < 0))
break;
if (last.Options != SliceOptions.AfterAllKeys && key.Compare(last) > 0)
break;
return page;
case SliceOptions.BeforeAllKeys:
if (first.Options == SliceOptions.BeforeAllKeys)
return page;
break;
case SliceOptions.AfterAllKeys:
if (last.Options == SliceOptions.AfterAllKeys)
return page;
break;
default:
throw new ArgumentException(key.Options.ToString());
}
itemsLeft--;
position++;
}
return null;
}
private NodeHeader* SearchPrefixed( MemorySlice key )
{
key.PrepareForSearching();
int numberOfEntries = NumberOfEntries;
if (numberOfEntries == 0)
{
LastSearchPosition = 0;
LastMatch = 1;
return null;
}
switch (key.Options)
{
case SliceOptions.Key:
{
var pageKey = CreateNewEmptyKey();
if (numberOfEntries == 1)
{
var node = GetNode(0);
SetNodeKey(node, ref pageKey);
LastMatch = key.Compare(pageKey);
LastSearchPosition = LastMatch > 0 ? 1 : 0;
return LastSearchPosition == 0 ? node : null;
}
int low = IsLeaf ? 0 : 1;
int high = numberOfEntries - 1;
int position = 0;
while (low <= high)
{
position = (low + high) >> 1;
var node = (NodeHeader*)(_base + KeysOffsets[position]);
SetNodeKey(node, ref pageKey);
LastMatch = key.Compare(pageKey);
if (LastMatch == 0)
break;
if (LastMatch > 0)
low = position + 1;
else
high = position - 1;
}
if (LastMatch > 0) // found entry less than key
{
position++; // move to the smallest entry larger than the key
}
Debug.Assert(position < ushort.MaxValue);
LastSearchPosition = position;
if (position >= numberOfEntries)
return null;
return GetNode(position);
}
case SliceOptions.BeforeAllKeys:
{
LastSearchPosition = 0;
LastMatch = 1;
return GetNode(0);
}
case SliceOptions.AfterAllKeys:
{
LastMatch = -1;
LastSearchPosition = numberOfEntries - 1;
return GetNode(LastSearchPosition);
}
default:
throw new NotSupportedException("This SliceOptions is not supported. Make sure you have updated this code when adding a new one.");
}
}
private NodeHeader *SearchPrefixed(MemorySlice key)
{
key.PrepareForSearching();
int numberOfEntries = NumberOfEntries;
if (numberOfEntries == 0)
{
LastSearchPosition = 0;
LastMatch = 1;
return(null);
}
switch (key.Options)
{
case SliceOptions.Key:
{
var pageKey = CreateNewEmptyKey();
if (numberOfEntries == 1)
{
var node = GetNode(0);
SetNodeKey(node, ref pageKey);
LastMatch = key.Compare(pageKey);
LastSearchPosition = LastMatch > 0 ? 1 : 0;
return(LastSearchPosition == 0 ? node : null);
}
int low = IsLeaf ? 0 : 1;
int high = numberOfEntries - 1;
int position = 0;
while (low <= high)
{
position = (low + high) >> 1;
var node = (NodeHeader *)(_base + KeysOffsets[position]);
SetNodeKey(node, ref pageKey);
LastMatch = key.Compare(pageKey);
if (LastMatch == 0)
{
break;
}
if (LastMatch > 0)
{
low = position + 1;
}
else
{
high = position - 1;
}
}
if (LastMatch > 0) // found entry less than key
{
position++; // move to the smallest entry larger than the key
}
Debug.Assert(position < ushort.MaxValue);
LastSearchPosition = position;
if (position >= numberOfEntries)
{
return(null);
}
return(GetNode(position));
}
case SliceOptions.BeforeAllKeys:
{
LastSearchPosition = 0;
LastMatch = 1;
return(GetNode(0));
}
case SliceOptions.AfterAllKeys:
{
LastMatch = -1;
LastSearchPosition = numberOfEntries - 1;
return(GetNode(LastSearchPosition));
}
default:
throw new NotSupportedException("This SliceOptions is not supported. Make sure you have updated this code when adding a new one.");
}
}
public NodeHeader *Search(MemorySlice key)
{
if (KeysPrefixed)
{
key.PrepareForSearching();
}
if (NumberOfEntries == 0)
{
LastSearchPosition = 0;
LastMatch = 1;
return(null);
}
if (key.Options == SliceOptions.BeforeAllKeys)
{
LastSearchPosition = 0;
LastMatch = 1;
return(GetNode(0));
}
if (key.Options == SliceOptions.AfterAllKeys)
{
LastMatch = -1;
LastSearchPosition = NumberOfEntries - 1;
return(GetNode(LastSearchPosition));
}
var pageKey = CreateNewEmptyKey();
if (NumberOfEntries == 1)
{
SetNodeKey(GetNode(0), ref pageKey);
LastMatch = key.Compare(pageKey);
LastSearchPosition = LastMatch > 0 ? 1 : 0;
return(LastSearchPosition == 0 ? GetNode(0) : null);
}
int low = IsLeaf ? 0 : 1;
int high = NumberOfEntries - 1;
int position = 0;
while (low <= high)
{
position = (low + high) >> 1;
var node = (NodeHeader *)(_base + KeysOffsets[position]);
SetNodeKey(node, ref pageKey);
LastMatch = key.Compare(pageKey);
if (LastMatch == 0)
{
break;
}
if (LastMatch > 0)
{
low = position + 1;
}
else
{
high = position - 1;
}
}
if (LastMatch > 0) // found entry less than key
{
position++; // move to the smallest entry larger than the key
}
Debug.Assert(position < ushort.MaxValue);
LastSearchPosition = position;
if (position >= NumberOfEntries)
{
return(null);
}
return(GetNode(position));
}
public NodeHeader* Search(MemorySlice key)
{
if(KeysPrefixed)
key.PrepareForSearching();
if (NumberOfEntries == 0)
{
LastSearchPosition = 0;
LastMatch = 1;
return null;
}
if (key.Options == SliceOptions.BeforeAllKeys)
{
LastSearchPosition = 0;
LastMatch = 1;
return GetNode(0);
}
if (key.Options == SliceOptions.AfterAllKeys)
{
LastMatch = -1;
LastSearchPosition = NumberOfEntries - 1;
return GetNode(LastSearchPosition);
}
var pageKey = CreateNewEmptyKey();
if (NumberOfEntries == 1)
{
SetNodeKey(GetNode(0), ref pageKey);
LastMatch = key.Compare(pageKey);
LastSearchPosition = LastMatch > 0 ? 1 : 0;
return LastSearchPosition == 0 ? GetNode(0) : null;
}
int low = IsLeaf ? 0 : 1;
int high = NumberOfEntries - 1;
int position = 0;
while (low <= high)
{
position = (low + high) >> 1;
var node = (NodeHeader*)(_base + KeysOffsets[position]);
SetNodeKey(node, ref pageKey);
LastMatch = key.Compare(pageKey);
if (LastMatch == 0)
break;
if (LastMatch > 0)
low = position + 1;
else
high = position - 1;
}
if (LastMatch > 0) // found entry less than key
{
position++; // move to the smallest entry larger than the key
}
Debug.Assert(position < ushort.MaxValue);
LastSearchPosition = position;
if (position >= NumberOfEntries)
return null;
return GetNode(position);
}