packagefs: Refactor UnpackingAttributeDirectoryCookie

Pull out a reusable base class AutoPackageAttributeDirectoryCookie.

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

@@ -22,6 +22,7 @@ HAIKU_PACKAGE_FS_SOURCES =
 	AttributeCookie.cpp
 	AttributeDirectoryCookie.cpp
 	AttributeIndex.cpp
+	AutoPackageAttributeDirectoryCookie.cpp
 	AutoPackageAttributes.cpp
 	BlockBufferPoolKernel.cpp
 	CachedDataReader.cpp

src/add-ons/kernel/file_systems/packagefs/nodes/AutoPackageAttributeDirectoryCookie.cpp

@@ -0,0 +1,110 @@
+/*
+ * Copyright 2011-2013, Ingo Weinhold, [email protected].
+ * Distributed under the terms of the MIT License.
+ */
+
+
+#include "AutoPackageAttributeDirectoryCookie.h"
+
+#include "DebugSupport.h"
+#include "Utils.h"
+
+
+AutoPackageAttributeDirectoryCookie::AutoPackageAttributeDirectoryCookie()
+	:
+	fState(AUTO_PACKAGE_ATTRIBUTE_ENUM_FIRST)
+{
+}
+
+
+AutoPackageAttributeDirectoryCookie::~AutoPackageAttributeDirectoryCookie()
+{
+}
+
+
+status_t
+AutoPackageAttributeDirectoryCookie::Read(dev_t volumeID, ino_t nodeID,
+	struct dirent* buffer, size_t bufferSize, uint32* _count)
+{
+	uint32 maxCount = *_count;
+	uint32 count = 0;
+
+	dirent* previousEntry = NULL;
+
+	String customAttributeName = CurrentCustomAttributeName();
+
+	while (fState < AUTO_PACKAGE_ATTRIBUTE_ENUM_COUNT
+		|| !customAttributeName.IsEmpty()) {
+		// 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;
+			}
+		}
+
+		// get the attribute name
+		const String& name = fState < AUTO_PACKAGE_ATTRIBUTE_ENUM_COUNT
+			? AutoPackageAttributes::NameForAttribute(
+				(AutoPackageAttribute)fState)
+			: customAttributeName;
+
+		// fill in the entry name -- checks whether the entry fits into the
+		// buffer
+		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);
+
+		if (fState < AUTO_PACKAGE_ATTRIBUTE_ENUM_COUNT)
+			fState++;
+		else
+			customAttributeName = NextCustomAttributeName();
+	}
+
+	*_count = count;
+	return B_OK;
+}
+
+
+status_t
+AutoPackageAttributeDirectoryCookie::Rewind()
+{
+	fState = AUTO_PACKAGE_ATTRIBUTE_ENUM_FIRST;
+
+	return B_OK;
+}
+
+
+String
+AutoPackageAttributeDirectoryCookie::CurrentCustomAttributeName()
+{
+	return String();
+}
+
+
+String
+AutoPackageAttributeDirectoryCookie::NextCustomAttributeName()
+{
+	return String();
+}

src/add-ons/kernel/file_systems/packagefs/nodes/AutoPackageAttributeDirectoryCookie.h

@@ -0,0 +1,41 @@
+/*
+ * Copyright 2011-2013, Ingo Weinhold, [email protected].
+ * Distributed under the terms of the MIT License.
+ */
+#ifndef AUTO_PACKAGE_ATTRIBUTE_DIRECTORY_COOKIE_H
+#define AUTO_PACKAGE_ATTRIBUTE_DIRECTORY_COOKIE_H
+
+
+#include "AttributeDirectoryCookie.h"
+#include "AutoPackageAttributes.h"
+
+
+/*!
+	When used for nodes that only have the automatic package attributes, the
+	class can be used as is. Otherwise subclassing is required.
+	Derived classes need to override Rewind() to rewind to their first
+	attribute, but also call the base class version. Furthermore they must
+	implement CurrentCustomAttributeName() to return the current attribute's
+	name and NextCustomAttributeName() to iterate to the next attribute and
+	return its name.
+*/
+class AutoPackageAttributeDirectoryCookie : public AttributeDirectoryCookie {
+public:
+								AutoPackageAttributeDirectoryCookie();
+	virtual						~AutoPackageAttributeDirectoryCookie();
+
+	virtual	status_t			Read(dev_t volumeID, ino_t nodeID,
+									struct dirent* buffer, size_t bufferSize,
+									uint32* _count);
+	virtual	status_t			Rewind();
+
+protected:
+	virtual	String				CurrentCustomAttributeName();
+	virtual	String				NextCustomAttributeName();
+
+private:
+			uint32				fState;
+};
+
+
+#endif	// AUTO_PACKAGE_ATTRIBUTE_DIRECTORY_COOKIE_H

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

@@ -8,15 +8,14 @@
 
 #include "DebugSupport.h"
 #include "PackageNode.h"
-#include "Utils.h"
 
 
 UnpackingAttributeDirectoryCookie::UnpackingAttributeDirectoryCookie(
 	PackageNode* packageNode)
 	:
+	AutoPackageAttributeDirectoryCookie(),
 	fPackageNode(packageNode),
-	fAttribute(NULL),
+	fAttribute(NULL)
-	fState(AUTO_PACKAGE_ATTRIBUTE_ENUM_FIRST)
 {
 	if (fPackageNode != NULL) {
 		fPackageNode->AcquireReference();
@@ -46,75 +45,27 @@ UnpackingAttributeDirectoryCookie::Open(PackageNode* packageNode,
 }
 
 
-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 (fState < AUTO_PACKAGE_ATTRIBUTE_ENUM_COUNT || 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;
-			}
-		}
-
-		// get the attribute name
-		const String& name = fState < AUTO_PACKAGE_ATTRIBUTE_ENUM_COUNT
-			? AutoPackageAttributes::NameForAttribute(
-				(AutoPackageAttribute)fState)
-			: fAttribute->Name();
-
-		// fill in the entry name -- checks whether the entry fits into the
-		// buffer
-		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);
-
-		if (fState < AUTO_PACKAGE_ATTRIBUTE_ENUM_COUNT)
-			fState++;
-		else
-			fAttribute = fPackageNode->Attributes().GetNext(fAttribute);
-	}
-
-	*_count = count;
-	return B_OK;
-}
-
-
 status_t
 UnpackingAttributeDirectoryCookie::Rewind()
 {
 	if (fPackageNode != NULL)
 		fAttribute = fPackageNode->Attributes().Head();
 
-	fState = AUTO_PACKAGE_ATTRIBUTE_ENUM_FIRST;
+	return AutoPackageAttributeDirectoryCookie::Rewind();
-
+}
-	return B_OK;
+
+
+String
+UnpackingAttributeDirectoryCookie::CurrentCustomAttributeName()
+{
+	return fAttribute != NULL ? fAttribute->Name() : String();
+}
+
+
+String
+UnpackingAttributeDirectoryCookie::NextCustomAttributeName()
+{
+	if (fAttribute != NULL)
+		fAttribute = fPackageNode->Attributes().GetNext(fAttribute);
+	return fAttribute != NULL ? fAttribute->Name() : String();
 }

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

@@ -6,17 +6,15 @@
 #define UNPACKING_ATTRIBUTE_DIRECTORY_COOKIE_H
 
 
-#include "AttributeDirectoryCookie.h"
+#include "AutoPackageAttributeDirectoryCookie.h"
-#include "AutoPackageAttributes.h"
 
 
-struct dirent;
-
 class PackageNode;
 class PackageNodeAttribute;
 
 
-class UnpackingAttributeDirectoryCookie : public AttributeDirectoryCookie {
+class UnpackingAttributeDirectoryCookie
+	: public AutoPackageAttributeDirectoryCookie {
 public:
 								UnpackingAttributeDirectoryCookie(
 									PackageNode* packageNode);
@@ -25,15 +23,15 @@ public:
 	static	status_t			Open(PackageNode* packageNode,
 									AttributeDirectoryCookie*& _cookie);
 
-	virtual	status_t			Read(dev_t volumeID, ino_t nodeID,
-									struct dirent* buffer, size_t bufferSize,
-									uint32* _count);
 	virtual	status_t			Rewind();
 
+protected:
+	virtual	String				CurrentCustomAttributeName();
+	virtual	String				NextCustomAttributeName();
+
 private:
 			PackageNode*		fPackageNode;
 			PackageNodeAttribute* fAttribute;
-			uint32				fState;
 };