ladybird/Kernel/TTY/MasterPTY.h
Ben Wiederhake c05c5a7ff4 Kernel: Clarify ambiguous {File,Description}::absolute_path
Found due to smelly code in InodeFile::absolute_path.

In particular, this replaces the following misleading methods:

File::absolute_path
This method *never* returns an actual path, and if called on an
InodeFile (which is impossible), it would VERIFY_NOT_REACHED().

OpenFileDescription::try_serialize_absolute_path
OpenFileDescription::absolute_path
These methods do not guarantee to return an actual path (just like the
other method), and just like Custody::absolute_path they do not
guarantee accuracy. In particular, just renaming the method made a
TOCTOU bug obvious.

The new method signatures use KResultOr, just like
try_serialize_absolute_path() already did.
2021-10-31 12:06:28 +01:00

50 lines
1.7 KiB
C++

/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#pragma once
#include <AK/Badge.h>
#include <Kernel/Devices/CharacterDevice.h>
#include <Kernel/DoubleBuffer.h>
namespace Kernel {
class SlavePTY;
class MasterPTY final : public CharacterDevice {
public:
static KResultOr<NonnullRefPtr<MasterPTY>> try_create(unsigned index);
virtual ~MasterPTY() override;
unsigned index() const { return m_index; }
String pts_name() const;
KResultOr<size_t> on_slave_write(const UserOrKernelBuffer&, size_t);
bool can_write_from_slave() const;
void notify_slave_closed(Badge<SlavePTY>);
bool is_closed() const { return m_closed; }
virtual KResultOr<NonnullOwnPtr<KString>> pseudo_path(const OpenFileDescription&) const override;
private:
explicit MasterPTY(unsigned index, NonnullOwnPtr<DoubleBuffer> buffer);
// ^CharacterDevice
virtual KResultOr<size_t> read(OpenFileDescription&, u64, UserOrKernelBuffer&, size_t) override;
virtual KResultOr<size_t> write(OpenFileDescription&, u64, const UserOrKernelBuffer&, size_t) override;
virtual bool can_read(const OpenFileDescription&, size_t) const override;
virtual bool can_write(const OpenFileDescription&, size_t) const override;
virtual KResult close() override;
virtual bool is_master_pty() const override { return true; }
virtual KResult ioctl(OpenFileDescription&, unsigned request, Userspace<void*> arg) override;
virtual StringView class_name() const override { return "MasterPTY"sv; }
RefPtr<SlavePTY> m_slave;
unsigned m_index;
bool m_closed { false };
NonnullOwnPtr<DoubleBuffer> m_buffer;
String m_pts_name;
};
}