ladybird/Kernel/FileSystem/TmpFS.h
Andreas Kling cda8f34876 Kernel/TmpFS: Remove inode map from TmpFS
The HashMap of InodeIndex->Inode in TmpFS only had one purpose: looking
up parent inodes by index.

Instead of using a map for this, we can simply give each inode a WeakPtr
to its parent inode. This saves us the trouble of dealing with the
fallibility of HashMap allocations, and it just generally simpler. :^)
2022-01-14 12:15:36 +01:00

88 lines
2.8 KiB
C++

/*
* Copyright (c) 2019-2020, Sergey Bugaev <bugaevc@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#pragma once
#include <Kernel/FileSystem/FileSystem.h>
#include <Kernel/FileSystem/Inode.h>
#include <Kernel/KBuffer.h>
namespace Kernel {
class TmpFSInode;
class TmpFS final : public FileSystem {
friend class TmpFSInode;
public:
virtual ~TmpFS() override;
static ErrorOr<NonnullRefPtr<TmpFS>> try_create();
virtual ErrorOr<void> initialize() override;
virtual StringView class_name() const override { return "TmpFS"sv; }
virtual bool supports_watchers() const override { return true; }
virtual Inode& root_inode() override;
private:
TmpFS();
RefPtr<TmpFSInode> m_root_inode;
unsigned m_next_inode_index { 1 };
unsigned next_inode_index();
};
class TmpFSInode final : public Inode {
friend class TmpFS;
public:
virtual ~TmpFSInode() override;
TmpFS& fs() { return static_cast<TmpFS&>(Inode::fs()); }
const TmpFS& fs() const { return static_cast<const TmpFS&>(Inode::fs()); }
// ^Inode
virtual ErrorOr<size_t> read_bytes(off_t, size_t, UserOrKernelBuffer& buffer, OpenFileDescription*) const override;
virtual InodeMetadata metadata() const override;
virtual ErrorOr<void> traverse_as_directory(Function<ErrorOr<void>(FileSystem::DirectoryEntryView const&)>) const override;
virtual ErrorOr<NonnullRefPtr<Inode>> lookup(StringView name) override;
virtual ErrorOr<void> flush_metadata() override;
virtual ErrorOr<size_t> write_bytes(off_t, size_t, const UserOrKernelBuffer& buffer, OpenFileDescription*) override;
virtual ErrorOr<NonnullRefPtr<Inode>> create_child(StringView name, mode_t, dev_t, UserID, GroupID) override;
virtual ErrorOr<void> add_child(Inode&, StringView name, mode_t) override;
virtual ErrorOr<void> remove_child(StringView name) override;
virtual ErrorOr<void> chmod(mode_t) override;
virtual ErrorOr<void> chown(UserID, GroupID) override;
virtual ErrorOr<void> truncate(u64) override;
virtual ErrorOr<void> set_atime(time_t) override;
virtual ErrorOr<void> set_ctime(time_t) override;
virtual ErrorOr<void> set_mtime(time_t) override;
private:
TmpFSInode(TmpFS& fs, const InodeMetadata& metadata, WeakPtr<TmpFSInode> parent);
static ErrorOr<NonnullRefPtr<TmpFSInode>> try_create(TmpFS&, InodeMetadata const& metadata, WeakPtr<TmpFSInode> parent);
static ErrorOr<NonnullRefPtr<TmpFSInode>> try_create_root(TmpFS&);
struct Child {
NonnullOwnPtr<KString> name;
NonnullRefPtr<TmpFSInode> inode;
IntrusiveListNode<Child> list_node {};
using List = IntrusiveList<&Child::list_node>;
};
Child* find_child_by_name(StringView);
InodeMetadata m_metadata;
WeakPtr<TmpFSInode> m_parent;
OwnPtr<KBuffer> m_content;
Child::List m_children;
};
}