ladybird/VirtualFileSystem/Ext2FileSystem.h
Andreas Kling 9cd0a34b5c BlockDevice -> DiskDevice.
BlockDevice was the wrong name for this abstraction, since a block device
is a type of file in a unix system, and we should use that name for that
concept in the fs implementation.
2018-10-16 11:21:49 +02:00

75 lines
3 KiB
C++

#pragma once
#include "DiskBackedFileSystem.h"
#include "UnixTypes.h"
#include <AK/Buffer.h>
#include <AK/OwnPtr.h>
struct ext2_group_desc;
struct ext2_inode;
struct ext2_super_block;
class Ext2FileSystem final : public DiskBackedFileSystem {
public:
static RetainPtr<Ext2FileSystem> create(RetainPtr<DiskDevice>&&);
virtual ~Ext2FileSystem() override;
private:
typedef unsigned BlockIndex;
typedef unsigned GroupIndex;
typedef unsigned InodeIndex;
explicit Ext2FileSystem(RetainPtr<DiskDevice>&&);
const ext2_super_block& superBlock() const;
const ext2_group_desc& blockGroupDescriptor(unsigned groupIndex) const;
unsigned firstBlockOfGroup(unsigned groupIndex) const;
unsigned inodesPerBlock() const;
unsigned inodesPerGroup() const;
unsigned blocksPerGroup() const;
unsigned inodeSize() const;
OwnPtr<ext2_inode> lookupExt2Inode(unsigned) const;
bool writeExt2Inode(unsigned, const ext2_inode&);
ByteBuffer readBlockContainingInode(unsigned inode, unsigned& blockIndex, unsigned& offset) const;
ByteBuffer readSuperBlock() const;
bool writeSuperBlock(const ext2_super_block&);
virtual bool initialize() override;
virtual const char* className() const override;
virtual InodeIdentifier rootInode() const override;
virtual bool writeInode(InodeIdentifier, const ByteBuffer&) override;
virtual bool enumerateDirectoryInode(InodeIdentifier, std::function<bool(const DirectoryEntry&)>) const override;
virtual InodeMetadata inodeMetadata(InodeIdentifier) const override;
virtual bool setModificationTime(InodeIdentifier, dword timestamp) override;
virtual InodeIdentifier createInode(InodeIdentifier parentInode, const String& name, Unix::mode_t, unsigned size) override;
virtual Unix::ssize_t readInodeBytes(InodeIdentifier, Unix::off_t offset, Unix::size_t count, byte* buffer) const override;
virtual InodeIdentifier makeDirectory(InodeIdentifier parentInode, const String& name, Unix::mode_t) override;
bool isDirectoryInode(unsigned) const;
unsigned allocateInode(unsigned preferredGroup, unsigned expectedSize);
Vector<BlockIndex> allocateBlocks(unsigned group, unsigned count);
unsigned groupIndexFromInode(unsigned) const;
Vector<unsigned> blockListForInode(const ext2_inode&) const;
void dumpBlockBitmap(unsigned groupIndex) const;
void dumpInodeBitmap(unsigned groupIndex) const;
template<typename F> void traverseInodeBitmap(unsigned groupIndex, F) const;
template<typename F> void traverseBlockBitmap(unsigned groupIndex, F) const;
bool addInodeToDirectory(unsigned directoryInode, unsigned inode, const String& name, byte fileType);
bool writeDirectoryInode(unsigned directoryInode, Vector<DirectoryEntry>&&);
bool setInodeAllocationState(unsigned inode, bool);
bool setBlockAllocationState(GroupIndex, BlockIndex, bool);
bool modifyLinkCount(InodeIndex, int delta);
unsigned m_blockGroupCount { 0 };
mutable ByteBuffer m_cachedSuperBlock;
mutable ByteBuffer m_cachedBlockGroupDescriptorTable;
};