ladybird/Kernel/FileSystem/Inode.h
Brian Gianforcaro 234c6ae32d Kernel: Change Inode::{read/write}_bytes interface to KResultOr<ssize_t>
The error handling in all these cases was still using the old style
negative values to indicate errors. We have a nicer solution for this
now with KResultOr<T>. This change switches the interface and then all
implementers to use the new style.
2021-05-02 13:27:37 +02:00

129 lines
4.3 KiB
C++

/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#pragma once
#include <AK/Function.h>
#include <AK/HashTable.h>
#include <AK/InlineLinkedList.h>
#include <AK/RefCounted.h>
#include <AK/String.h>
#include <AK/WeakPtr.h>
#include <Kernel/FileSystem/FIFO.h>
#include <Kernel/FileSystem/FileSystem.h>
#include <Kernel/FileSystem/InodeIdentifier.h>
#include <Kernel/FileSystem/InodeMetadata.h>
#include <Kernel/Forward.h>
#include <Kernel/KResult.h>
#include <Kernel/Lock.h>
namespace Kernel {
class Inode : public RefCounted<Inode>
, public Weakable<Inode>
, public InlineLinkedListNode<Inode> {
friend class VFS;
friend class FS;
public:
virtual ~Inode();
virtual void one_ref_left() { }
FS& fs() { return m_fs; }
const FS& fs() const { return m_fs; }
unsigned fsid() const { return m_fs.fsid(); }
InodeIndex index() const { return m_index; }
size_t size() const { return metadata().size; }
bool is_symlink() const { return metadata().is_symlink(); }
bool is_directory() const { return metadata().is_directory(); }
bool is_character_device() const { return metadata().is_character_device(); }
mode_t mode() const { return metadata().mode; }
InodeIdentifier identifier() const { return { fsid(), index() }; }
virtual InodeMetadata metadata() const = 0;
KResultOr<NonnullOwnPtr<KBuffer>> read_entire(FileDescription* = nullptr) const;
virtual KResult attach(FileDescription&) { return KSuccess; }
virtual void detach(FileDescription&) { }
virtual void did_seek(FileDescription&, off_t) { }
virtual KResultOr<ssize_t> read_bytes(off_t, ssize_t, UserOrKernelBuffer& buffer, FileDescription*) const = 0;
virtual KResult traverse_as_directory(Function<bool(const FS::DirectoryEntryView&)>) const = 0;
virtual RefPtr<Inode> lookup(StringView name) = 0;
virtual KResultOr<ssize_t> write_bytes(off_t, ssize_t, const UserOrKernelBuffer& data, FileDescription*) = 0;
virtual KResultOr<NonnullRefPtr<Inode>> create_child(const String& name, mode_t, dev_t, uid_t, gid_t) = 0;
virtual KResult add_child(Inode&, const StringView& name, mode_t) = 0;
virtual KResult remove_child(const StringView& name) = 0;
virtual KResultOr<size_t> directory_entry_count() const = 0;
virtual KResult chmod(mode_t) = 0;
virtual KResult chown(uid_t, gid_t) = 0;
virtual KResult truncate(u64) { return KSuccess; }
virtual KResultOr<NonnullRefPtr<Custody>> resolve_as_link(Custody& base, RefPtr<Custody>* out_parent, int options, int symlink_recursion_level) const;
virtual KResultOr<int> get_block_address(int) { return ENOTSUP; }
LocalSocket* socket() { return m_socket.ptr(); }
const LocalSocket* socket() const { return m_socket.ptr(); }
bool bind_socket(LocalSocket&);
bool unbind_socket();
virtual FileDescription* preopen_fd() { return nullptr; };
bool is_metadata_dirty() const { return m_metadata_dirty; }
virtual KResult set_atime(time_t);
virtual KResult set_ctime(time_t);
virtual KResult set_mtime(time_t);
virtual KResult increment_link_count();
virtual KResult decrement_link_count();
virtual void flush_metadata() = 0;
void will_be_destroyed();
void set_shared_vmobject(SharedInodeVMObject&);
RefPtr<SharedInodeVMObject> shared_vmobject() const;
bool is_shared_vmobject(const SharedInodeVMObject&) const;
static InlineLinkedList<Inode>& all_with_lock();
static void sync();
bool has_watchers() const { return !m_watchers.is_empty(); }
void register_watcher(Badge<InodeWatcher>, InodeWatcher&);
void unregister_watcher(Badge<InodeWatcher>, InodeWatcher&);
NonnullRefPtr<FIFO> fifo();
// For InlineLinkedListNode.
Inode* m_next { nullptr };
Inode* m_prev { nullptr };
static SpinLock<u32>& all_inodes_lock();
protected:
Inode(FS& fs, InodeIndex);
void set_metadata_dirty(bool);
KResult prepare_to_write_data();
void did_add_child(const InodeIdentifier&);
void did_remove_child(const InodeIdentifier&);
mutable Lock m_lock { "Inode" };
private:
FS& m_fs;
InodeIndex m_index { 0 };
WeakPtr<SharedInodeVMObject> m_shared_vmobject;
RefPtr<LocalSocket> m_socket;
HashTable<InodeWatcher*> m_watchers;
bool m_metadata_dirty { false };
RefPtr<FIFO> m_fifo;
};
}