Attribute dir access kernel interface abstraction

* Introduce interface AttributeDirectoryCookie and currently only
  implementation UnpackingAttributeDirectoryCookie. This is an interface
  for reading/rewinding an attribute directory.
* Add abstract virtual Node::OpenAttributeDirectory() method that
  returns an AttributeDirectoryCookie and implement it for derived
  classes.
* In the kernel interface attribute directory hooks use
  AttributeDirectoryCookie now.

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

@@ -0,0 +1,12 @@
+/*
+ * Copyright 2011, Ingo Weinhold, ingo_weinhold@gmx.de.
+ * Distributed under the terms of the MIT License.
+ */
+
+
+#include "AttributeDirectoryCookie.h"
+
+
+AttributeDirectoryCookie::~AttributeDirectoryCookie()
+{
+}

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

@@ -0,0 +1,26 @@
+/*
+ * Copyright 2011, Ingo Weinhold, ingo_weinhold@gmx.de.
+ * Distributed under the terms of the MIT License.
+ */
+#ifndef ATTRIBUTE_DIRECTORY_COOKIE_H
+#define ATTRIBUTE_DIRECTORY_COOKIE_H
+
+
+#include <dirent.h>
+
+#include <SupportDefs.h>
+
+
+class AttributeDirectoryCookie {
+public:
+	virtual						~AttributeDirectoryCookie();
+
+	virtual	status_t			Close() = 0;
+	virtual	status_t			Read(dev_t volumeID, ino_t nodeID,
+									struct dirent* buffer, size_t bufferSize,
+									uint32* _count) = 0;
+	virtual	status_t			Rewind() = 0;
+};
+
+
+#endif	// ATTRIBUTE_DIRECTORY_COOKIE_H

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

@@ -8,6 +8,7 @@
 
 #include "DebugSupport.h"
 #include "UnpackingAttributeCookie.h"
+#include "UnpackingAttributeDirectoryCookie.h"
 #include "Utils.h"
 
 
@@ -172,6 +173,14 @@ Directory::ReadSymlink(void* buffer, size_t* bufferSize)
 }
 
 
+status_t
+Directory::OpenAttributeDirectory(AttributeDirectoryCookie*& _cookie)
+{
+	return UnpackingAttributeDirectoryCookie::Open(fPackageDirectories.Head(),
+		_cookie);
+}
+
+
 status_t
 Directory::OpenAttribute(const char* name, int openMode,
 	AttributeCookie*& _cookie)

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

@@ -51,6 +51,8 @@ public:
 	virtual	status_t			ReadSymlink(void* buffer,
 									size_t* bufferSize);
 
+	virtual	status_t			OpenAttributeDirectory(
+									AttributeDirectoryCookie*& _cookie);
 	virtual	status_t			OpenAttribute(const char* name, int openMode,
 									AttributeCookie*& _cookie);
 

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

@@ -8,6 +8,7 @@ UsePrivateHeaders shared ;
 
 HAIKU_PACKAGE_FS_SOURCES =
 	AttributeCookie.cpp
+	AttributeDirectoryCookie.cpp
 	BlockBufferCacheKernel.cpp
 	DebugSupport.cpp
 	Dependency.cpp
@@ -28,6 +29,7 @@ HAIKU_PACKAGE_FS_SOURCES =
 	PackageSymlink.cpp
 	Resolvable.cpp
 	UnpackingAttributeCookie.cpp
+	UnpackingAttributeDirectoryCookie.cpp
 	Version.cpp
 	Volume.cpp
 ;

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

@@ -11,6 +11,7 @@
 #include <algorithm>
 
 #include "UnpackingAttributeCookie.h"
+#include "UnpackingAttributeDirectoryCookie.h"
 #include "Utils.h"
 
 
@@ -194,6 +195,14 @@ LeafNode::ReadSymlink(void* buffer, size_t* bufferSize)
 }
 
 
+status_t
+LeafNode::OpenAttributeDirectory(AttributeDirectoryCookie*& _cookie)
+{
+	return UnpackingAttributeDirectoryCookie::Open(fPackageNodes.Head(),
+		_cookie);
+}
+
+
 status_t
 LeafNode::OpenAttribute(const char* name, int openMode,
 	AttributeCookie*& _cookie)

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

@@ -38,6 +38,8 @@ public:
 	virtual	status_t			ReadSymlink(void* buffer,
 									size_t* bufferSize);
 
+	virtual	status_t			OpenAttributeDirectory(
+									AttributeDirectoryCookie*& _cookie);
 	virtual	status_t			OpenAttribute(const char* name, int openMode,
 									AttributeCookie*& _cookie);
 

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

@@ -18,6 +18,7 @@
 
 
 class AttributeCookie;
+class AttributeDirectoryCookie;
 class Directory;
 class PackageNode;
 
@@ -64,6 +65,8 @@ public:
 	virtual	status_t			ReadSymlink(void* buffer,
 									size_t* bufferSize) = 0;
 
+	virtual	status_t			OpenAttributeDirectory(
+									AttributeDirectoryCookie*& _cookie) = 0;
 	virtual	status_t			OpenAttribute(const char* name, int openMode,
 									AttributeCookie*& _cookie) = 0;
 

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

@@ -0,0 +1,116 @@
+/*
+ * Copyright 2011, Ingo Weinhold, ingo_weinhold@gmx.de.
+ * Distributed under the terms of the MIT License.
+ */
+
+
+#include "UnpackingAttributeDirectoryCookie.h"
+
+#include "DebugSupport.h"
+#include "PackageNode.h"
+#include "Utils.h"
+
+
+UnpackingAttributeDirectoryCookie::UnpackingAttributeDirectoryCookie(
+	PackageNode* packageNode)
+	:
+	fPackageNode(packageNode),
+	fAttribute(NULL)
+{
+	if (fPackageNode != NULL) {
+		fPackageNode->AcquireReference();
+		fAttribute = fPackageNode->Attributes().Head();
+	}
+}
+
+
+UnpackingAttributeDirectoryCookie::~UnpackingAttributeDirectoryCookie()
+{
+	if (fPackageNode != NULL)
+		fPackageNode->ReleaseReference();
+}
+
+
+/*static*/ status_t
+UnpackingAttributeDirectoryCookie::Open(PackageNode* packageNode,
+	AttributeDirectoryCookie*& _cookie)
+{
+	UnpackingAttributeDirectoryCookie* cookie = new(std::nothrow)
+		UnpackingAttributeDirectoryCookie(packageNode);
+	if (cookie == NULL)
+		return B_NO_MEMORY;
+
+	_cookie = cookie;
+	return B_OK;
+}
+
+
+status_t
+UnpackingAttributeDirectoryCookie::Close()
+{
+	return B_OK;
+}
+
+
+status_t
+UnpackingAttributeDirectoryCookie::Read(dev_t volumeID, ino_t nodeID,
+	struct dirent* buffer, size_t bufferSize, uint32* _count)
+{
+	uint32 maxCount = *_count;
+	uint32 count = 0;
+
+	dirent* previousEntry = NULL;
+
+	while (fAttribute != NULL) {
+		// don't read more entries than requested
+		if (count >= maxCount)
+			break;
+
+		// align the buffer for subsequent entries
+		if (count > 0) {
+			addr_t offset = (addr_t)buffer % 8;
+			if (offset > 0) {
+				offset = 8 - offset;
+				if (bufferSize <= offset)
+					break;
+
+				previousEntry->d_reclen += offset;
+				buffer = (dirent*)((addr_t)buffer + offset);
+				bufferSize -= offset;
+			}
+		}
+
+		// fill in the entry name -- checks whether the entry fits into the
+		// buffer
+		const char* name = fAttribute->Name();
+		if (!set_dirent_name(buffer, bufferSize, name, strlen(name))) {
+			if (count == 0)
+				RETURN_ERROR(B_BUFFER_OVERFLOW);
+			break;
+		}
+
+		// fill in the other data
+		buffer->d_dev = volumeID;
+		buffer->d_ino = nodeID;
+
+		count++;
+		previousEntry = buffer;
+		bufferSize -= buffer->d_reclen;
+		buffer = (dirent*)((addr_t)buffer + buffer->d_reclen);
+
+		fAttribute = fPackageNode->Attributes().GetNext(fAttribute);
+	}
+
+	*_count = count;
+	return B_OK;
+}
+
+
+status_t
+UnpackingAttributeDirectoryCookie::Rewind()
+{
+	if (fPackageNode != NULL)
+		fAttribute = fPackageNode->Attributes().Head();
+
+	return B_OK;
+}

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

@@ -0,0 +1,39 @@
+/*
+ * Copyright 2011, Ingo Weinhold, ingo_weinhold@gmx.de.
+ * Distributed under the terms of the MIT License.
+ */
+#ifndef UNPACKING_ATTRIBUTE_DIRECTORY_COOKIE_H
+#define UNPACKING_ATTRIBUTE_DIRECTORY_COOKIE_H
+
+
+#include "AttributeDirectoryCookie.h"
+
+
+struct dirent;
+
+class PackageNode;
+class PackageNodeAttribute;
+
+
+class UnpackingAttributeDirectoryCookie : public AttributeDirectoryCookie {
+public:
+								UnpackingAttributeDirectoryCookie(
+									PackageNode* packageNode);
+	virtual						~UnpackingAttributeDirectoryCookie();
+
+	static	status_t			Open(PackageNode* packageNode,
+									AttributeDirectoryCookie*& _cookie);
+
+	virtual	status_t			Close();
+	virtual	status_t			Read(dev_t volumeID, ino_t nodeID,
+									struct dirent* buffer, size_t bufferSize,
+									uint32* _count);
+	virtual	status_t			Rewind();
+
+private:
+			PackageNode*		fPackageNode;
+			PackageNodeAttribute* fAttribute;
+};
+
+
+#endif	// UNPACKING_ATTRIBUTE_DIRECTORY_COOKIE_H

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

@@ -18,6 +18,7 @@
 #include <AutoDeleter.h>
 
 #include "AttributeCookie.h"
+#include "AttributeDirectoryCookie.h"
 #include "DebugSupport.h"
 #include "Directory.h"
 #include "GlobalFactory.h"
@@ -663,50 +664,6 @@ packagefs_rewind_dir(fs_volume* fsVolume, fs_vnode* fsNode, void* _cookie)
 // #pragma mark - Attribute Directories
 
 
-struct AttributeDirectoryCookie {
-	Node*					node;
-	PackageNode*			packageNode;
-	PackageNodeAttribute*	attribute;
-
-	AttributeDirectoryCookie(Node* node)
-		:
-		node(node),
-		packageNode(node->GetPackageNode()),
-		attribute(NULL)
-	{
-		if (packageNode != NULL) {
-			packageNode->AcquireReference();
-			attribute = packageNode->Attributes().Head();
-		}
-	}
-
-	~AttributeDirectoryCookie()
-	{
-		if (packageNode != NULL)
-			packageNode->ReleaseReference();
-	}
-
-	PackageNodeAttribute* Current() const
-	{
-		return attribute;
-	}
-
-	void Next()
-	{
-		if (attribute == NULL)
-			return;
-
-		attribute = packageNode->Attributes().GetNext(attribute);
-	}
-
-	void Rewind()
-	{
-		if (packageNode != NULL)
-			attribute = packageNode->Attributes().Head();
-	}
-};
-
-
 status_t
 packagefs_open_attr_dir(fs_volume* fsVolume, fs_vnode* fsNode, void** _cookie)
 {
@@ -722,10 +679,10 @@ packagefs_open_attr_dir(fs_volume* fsVolume, fs_vnode* fsNode, void** _cookie)
 
 	// create a cookie
 	NodeReadLocker nodeLocker(node);
-	AttributeDirectoryCookie* cookie
-		= new(std::nothrow) AttributeDirectoryCookie(node);
-	if (cookie == NULL)
-		RETURN_ERROR(B_NO_MEMORY);
+	AttributeDirectoryCookie* cookie;
+	error = node->OpenAttributeDirectory(cookie);
+	if (error != B_OK)
+		RETURN_ERROR(error);
 
 	*_cookie = cookie;
 	return B_OK;
@@ -735,7 +692,8 @@ packagefs_open_attr_dir(fs_volume* fsVolume, fs_vnode* fsNode, void** _cookie)
 status_t
 packagefs_close_attr_dir(fs_volume* fsVolume, fs_vnode* fsNode, void* _cookie)
 {
-	return B_OK;
+	AttributeDirectoryCookie* cookie = (AttributeDirectoryCookie*)_cookie;
+	return cookie->Close();
 }
 
 
@@ -771,53 +729,7 @@ packagefs_read_attr_dir(fs_volume* fsVolume, fs_vnode* fsNode, void* _cookie,
 	TOUCH(volume);
 	TOUCH(node);
 
-	uint32 maxCount = *_count;
-	uint32 count = 0;
-
-	dirent* previousEntry = NULL;
-
-	while (PackageNodeAttribute* attribute = cookie->Current()) {
-		// don't read more entries than requested
-		if (count >= maxCount)
-			break;
-
-		// align the buffer for subsequent entries
-		if (count > 0) {
-			addr_t offset = (addr_t)buffer % 8;
-			if (offset > 0) {
-				offset = 8 - offset;
-				if (bufferSize <= offset)
-					break;
-
-				previousEntry->d_reclen += offset;
-				buffer = (dirent*)((addr_t)buffer + offset);
-				bufferSize -= offset;
-			}
-		}
-
-		// fill in the entry name -- checks whether the entry fits into the
-		// buffer
-		const char* name = attribute->Name();
-		if (!set_dirent_name(buffer, bufferSize, name, strlen(name))) {
-			if (count == 0)
-				RETURN_ERROR(B_BUFFER_OVERFLOW);
-			break;
-		}
-
-		// fill in the other data
-		buffer->d_dev = volume->ID();
-		buffer->d_ino = node->ID();
-
-		count++;
-		previousEntry = buffer;
-		bufferSize -= buffer->d_reclen;
-		buffer = (dirent*)((addr_t)buffer + buffer->d_reclen);
-
-		cookie->Next();
-	}
-
-	*_count = count;
-	return B_OK;
+	return cookie->Read(volume->ID(), node->ID(), buffer, bufferSize, _count);
 }
 
 
@@ -833,9 +745,7 @@ packagefs_rewind_attr_dir(fs_volume* fsVolume, fs_vnode* fsNode, void* _cookie)
 	TOUCH(volume);
 	TOUCH(node);
 
-	cookie->Rewind();
-
-	return B_OK;
+	return cookie->Rewind();
 }