ladybird/Kernel/FileSystem/TmpFS.h
Andreas Kling 280694bb46 Kernel: Update atime/ctime/mtime timestamps atomically
Instead of having three separate APIs (one for each timestamp),
there's now only Inode::update_timestamps() and it takes 3x optional
timestamps. The non-empty timestamps are updated while holding the inode
mutex, and the outside world no longer has to look at intermediate
timestamp states.
2022-08-22 17:56:03 +02:00

86 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<NonnullLockRefPtr<FileSystem>> 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();
LockRefPtr<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()); }
TmpFS const& fs() const { return static_cast<TmpFS const&>(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<NonnullLockRefPtr<Inode>> lookup(StringView name) override;
virtual ErrorOr<void> flush_metadata() override;
virtual ErrorOr<size_t> write_bytes(off_t, size_t, UserOrKernelBuffer const& buffer, OpenFileDescription*) override;
virtual ErrorOr<NonnullLockRefPtr<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> update_timestamps(Optional<time_t> atime, Optional<time_t> ctime, Optional<time_t> mtime) override;
private:
TmpFSInode(TmpFS& fs, InodeMetadata const& metadata, LockWeakPtr<TmpFSInode> parent);
static ErrorOr<NonnullLockRefPtr<TmpFSInode>> try_create(TmpFS&, InodeMetadata const& metadata, LockWeakPtr<TmpFSInode> parent);
static ErrorOr<NonnullLockRefPtr<TmpFSInode>> try_create_root(TmpFS&);
struct Child {
NonnullOwnPtr<KString> name;
NonnullLockRefPtr<TmpFSInode> inode;
IntrusiveListNode<Child> list_node {};
using List = IntrusiveList<&Child::list_node>;
};
Child* find_child_by_name(StringView);
InodeMetadata m_metadata;
LockWeakPtr<TmpFSInode> m_parent;
OwnPtr<KBuffer> m_content;
Child::List m_children;
};
}