Add size index support

* Add class SizeIndex.
* Create and add an instance of it in Volume mount.

src/add-ons/kernel/file_systems/packagefs/Jamfile

@@ -38,6 +38,7 @@ HAIKU_PACKAGE_FS_SOURCES =
 	PackageSymlink.cpp
 	Resolvable.cpp
 	ResolvableFamily.cpp
+	SizeIndex.cpp
 	UnpackingAttributeCookie.cpp
 	UnpackingAttributeDirectoryCookie.cpp
 	UnpackingDirectory.cpp

src/add-ons/kernel/file_systems/packagefs/SizeIndex.cpp

@@ -0,0 +1,288 @@
+/*
+ * Copyright 2011, Ingo Weinhold, [email protected].
+ * Distributed under the terms of the MIT License.
+ */
+
+
+#include "SizeIndex.h"
+
+#include <new>
+
+#include <TypeConstants.h>
+
+#include <util/SinglyLinkedList.h>
+#include <util/TwoKeyAVLTree.h>
+
+#include "DebugSupport.h"
+#include "IndexImpl.h"
+#include "Node.h"
+#include "Volume.h"
+
+
+// #pragma mark - SizeIndexPrimaryKey
+
+
+class SizeIndexPrimaryKey {
+public:
+	SizeIndexPrimaryKey(Node* node, off_t size)
+		:
+		node(node),
+		size(size)
+	{
+	}
+
+	SizeIndexPrimaryKey(Node* node)
+		:
+		node(node),
+		size(node->FileSize())
+	{
+	}
+
+	SizeIndexPrimaryKey(off_t size)
+		:
+		node(NULL),
+		size(size)
+	{
+	}
+
+	Node*	node;
+	off_t	size;
+};
+
+
+// #pragma mark - SizeIndexGetPrimaryKey
+
+
+class SizeIndexGetPrimaryKey {
+public:
+	inline SizeIndexPrimaryKey operator()(Node* a)
+	{
+		return SizeIndexPrimaryKey(a);
+	}
+
+	inline SizeIndexPrimaryKey operator()(Node* a) const
+	{
+		return SizeIndexPrimaryKey(a);
+	}
+};
+
+
+// #pragma mark - SizeIndexPrimaryKeyCompare
+
+
+class SizeIndexPrimaryKeyCompare {
+public:
+	inline int operator()(const SizeIndexPrimaryKey &a,
+		const SizeIndexPrimaryKey &b) const
+	{
+		if (a.node != NULL && a.node == b.node)
+			return 0;
+		if (a.size < b.size)
+			return -1;
+		if (a.size > b.size)
+			return 1;
+		return 0;
+	}
+};
+
+
+// #pragma mark - NodeTree
+
+
+typedef TwoKeyAVLTree<Node*, SizeIndexPrimaryKey, SizeIndexPrimaryKeyCompare,
+	SizeIndexGetPrimaryKey> _NodeTree;
+class SizeIndex::NodeTree : public _NodeTree {};
+
+
+// #pragma mark - IteratorList
+
+
+class SizeIndex::IteratorList : public SinglyLinkedList<Iterator> {};
+
+
+// #pragma mark - Iterator
+
+
+struct SizeIndex::IteratorPolicy {
+	typedef SizeIndex				Index;
+	typedef off_t					Value;
+	typedef SizeIndex::NodeTree		NodeTree;
+
+	static NodeTree* GetNodeTree(Index* index)
+	{
+		return index->fNodes;
+	}
+
+	static void GetNodeValue(Node* node, void* buffer, size_t* _keyLength)
+	{
+		*(off_t*)buffer = node->FileSize();
+		*_keyLength = sizeof(off_t);
+	}
+};
+
+
+class SizeIndex::Iterator : public GenericIndexIterator<IteratorPolicy>,
+	public SinglyLinkedListLinkImpl<Iterator> {
+public:
+	virtual	void				NodeChanged(Node* node, uint32 statFields,
+									const OldNodeAttributes& oldAttributes);
+};
+
+
+// #pragma mark - SizeIndex
+
+
+SizeIndex::SizeIndex()
+	:
+	Index(),
+	fNodes(NULL),
+	fIteratorsToUpdate(NULL)
+{
+}
+
+
+SizeIndex::~SizeIndex()
+{
+	if (IsListening())
+		fVolume->RemoveNodeListener(this);
+
+	ASSERT(fIteratorsToUpdate->IsEmpty());
+
+	delete fIteratorsToUpdate;
+	delete fNodes;
+}
+
+
+status_t
+SizeIndex::Init(Volume* volume)
+{
+	status_t error = Index::Init(volume, "size", B_INT64_TYPE, true,
+		sizeof(off_t));
+	if (error != B_OK)
+		return error;
+
+	fVolume->AddNodeListener(this, NULL);
+
+	fNodes = new(std::nothrow) NodeTree;
+	fIteratorsToUpdate = new(std::nothrow) IteratorList;
+	if (fNodes == NULL || fIteratorsToUpdate == NULL)
+		return B_NO_MEMORY;
+
+	return B_OK;
+}
+
+
+int32
+SizeIndex::CountEntries() const
+{
+	return fNodes->CountItems();
+}
+
+
+void
+SizeIndex::NodeAdded(Node* node)
+{
+	fNodes->Insert(node);
+}
+
+
+void
+SizeIndex::NodeRemoved(Node* node)
+{
+	fNodes->Remove(node, node);
+}
+
+
+void
+SizeIndex::NodeChanged(Node* node, uint32 statFields,
+	const OldNodeAttributes& oldAttributes)
+{
+	IteratorList iterators;
+	iterators.MoveFrom(fIteratorsToUpdate);
+
+	off_t oldSize = oldAttributes.FileSize();
+	off_t newSize = node->FileSize();
+	if (newSize == oldSize)
+		return;
+
+	NodeTree::Iterator nodeIterator;
+	Node** foundNode = fNodes->Find(SizeIndexPrimaryKey(node, oldSize), node,
+		&nodeIterator);
+
+	if (foundNode == NULL || *foundNode != node)
+		return;
+
+	// move the iterators that point to the node to the previous node
+	for (IteratorList::Iterator it = iterators.GetIterator();
+			Iterator* iterator = it.Next();) {
+		iterator->NodeChangeBegin(node);
+	}
+
+	// remove and re-insert the node
+	nodeIterator.Remove();
+	if (fNodes->Insert(node) != B_OK) {
+		fIteratorsToUpdate->MakeEmpty();
+		return;
+	}
+
+	// Move the iterators to the next node again. If the node hasn't changed
+	// its place, they will point to it again, otherwise to the node originally
+	// succeeding it.
+	for (IteratorList::Iterator it = iterators.GetIterator();
+			Iterator* iterator = it.Next();) {
+		iterator->NodeChangeEnd(node);
+	}
+
+	// update live queries
+	fVolume->UpdateLiveQueries(node, Name(), Type(),
+		(const uint8*)&oldSize, sizeof(oldSize), (const uint8*)&newSize,
+		sizeof(newSize));
+}
+
+
+AbstractIndexIterator*
+SizeIndex::InternalGetIterator()
+{
+	Iterator* iterator = new(std::nothrow) Iterator;
+	if (iterator != NULL) {
+		if (!iterator->SetTo(this, 0, true)) {
+			delete iterator;
+			iterator = NULL;
+		}
+	}
+	return iterator;
+}
+
+
+AbstractIndexIterator*
+SizeIndex::InternalFind(const void* key, size_t length)
+{
+	if (!key || length != sizeof(off_t))
+		return NULL;
+	Iterator* iterator = new(std::nothrow) Iterator;
+	if (iterator != NULL) {
+		if (!iterator->SetTo(this, *(const off_t*)key)) {
+			delete iterator;
+			iterator = NULL;
+		}
+	}
+	return iterator;
+}
+
+
+void
+SizeIndex::_AddIteratorToUpdate(Iterator* iterator)
+{
+	fIteratorsToUpdate->Add(iterator);
+}
+
+
+// #pragma mark - Iterator
+
+
+void
+SizeIndex::Iterator::NodeChanged(Node* node, uint32 statFields,
+	const OldNodeAttributes& oldAttributes)
+{
+	fIndex->_AddIteratorToUpdate(this);
+}

src/add-ons/kernel/file_systems/packagefs/SizeIndex.h

@@ -0,0 +1,51 @@
+/*
+ * Copyright 2011, Ingo Weinhold, [email protected].
+ * Distributed under the terms of the MIT License.
+ */
+#ifndef SIZE_INDEX_H
+#define SIZE_INDEX_H
+
+
+#include "Index.h"
+#include "NodeListener.h"
+
+
+class SizeIndex : public Index, private NodeListener {
+public:
+								SizeIndex();
+	virtual						~SizeIndex();
+
+			status_t			Init(Volume* volume);
+
+	virtual	int32				CountEntries() const;
+
+private:
+	virtual	void				NodeAdded(Node* node);
+	virtual	void				NodeRemoved(Node* node);
+	virtual	void				NodeChanged(Node* node, uint32 statFields,
+									const OldNodeAttributes& oldAttributes);
+
+protected:
+	virtual	AbstractIndexIterator* InternalGetIterator();
+	virtual	AbstractIndexIterator* InternalFind(const void* key,
+									size_t length);
+
+private:
+			struct IteratorPolicy;
+			class Iterator;
+			class IteratorList;
+			class NodeTree;
+			friend class Iterator;
+			friend struct IteratorPolicy;
+
+private:
+			void				_AddIteratorToUpdate(Iterator* iterator);
+// 			void				_RemoveIterator(Iterator* iterator);
+
+private:
+			NodeTree*			fNodes;
+			IteratorList*		fIteratorsToUpdate;
+};
+
+
+#endif	// SIZE_INDEX_H

src/add-ons/kernel/file_systems/packagefs/Volume.cpp

@@ -41,6 +41,7 @@
 #include "PackageLinksDirectory.h"
 #include "PackageSymlink.h"
 #include "Resolvable.h"
+#include "SizeIndex.h"
 #include "UnpackingLeafNode.h"
 #include "UnpackingDirectory.h"
 #include "Version.h"
@@ -510,17 +511,34 @@ Volume::Mount(const char* parameterString)
 		RETURN_ERROR(error);
 
 	// create the name index
-	NameIndex* index = new(std::nothrow) NameIndex;
-	if (index == NULL)
-		RETURN_ERROR(B_NO_MEMORY);
+	{
+		NameIndex* index = new(std::nothrow) NameIndex;
+		if (index == NULL)
+			RETURN_ERROR(B_NO_MEMORY);
 
-	error = index->Init(this);
-	if (error != B_OK) {
-		delete index;
-		RETURN_ERROR(error);
+		error = index->Init(this);
+		if (error != B_OK) {
+			delete index;
+			RETURN_ERROR(error);
+		}
+
+		fIndices.Insert(index);
 	}
 
-	fIndices.Insert(index);
+	// create the size index
+	{
+		SizeIndex* index = new(std::nothrow) SizeIndex;
+		if (index == NULL)
+			RETURN_ERROR(B_NO_MEMORY);
+
+		error = index->Init(this);
+		if (error != B_OK) {
+			delete index;
+			RETURN_ERROR(error);
+		}
+
+		fIndices.Insert(index);
+	}
 
 	// get the mount parameters
 	const char* packages = NULL;