ladybird/Kernel/Devices/DeviceManagement.h
Liav A 11ead5c84f Kernel: Get RefPtr<Device> from the DeviceManagement::get_device method
Instead of returning a raw pointer, which could be technically invalid
when using it in the caller function, we return a valid RefPtr of such
device.

This ensures that the code in DevPtsFS is now safe from a rare race
condition in which the SlavePTY device is gone but we still have a
pointer to it.
2024-03-13 15:33:47 -06:00

80 lines
2.6 KiB
C++

/*
* Copyright (c) 2021, Liav A. <liavalb@hotmail.co.il>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#pragma once
#include <AK/Badge.h>
#include <AK/Error.h>
#include <AK/OwnPtr.h>
#include <AK/Types.h>
#include <Kernel/API/DeviceEvent.h>
#include <Kernel/API/TimePage.h>
#include <Kernel/Arch/RegisterState.h>
#include <Kernel/Devices/CharacterDevice.h>
#include <Kernel/Devices/Device.h>
#include <Kernel/Devices/Generic/ConsoleDevice.h>
#include <Kernel/Devices/Generic/DeviceControlDevice.h>
#include <Kernel/Devices/Generic/NullDevice.h>
#include <Kernel/Library/LockRefPtr.h>
#include <Kernel/UnixTypes.h>
namespace Kernel {
class DeviceManagement {
public:
DeviceManagement();
static void initialize();
static DeviceManagement& the();
void attach_null_device(NullDevice const&);
void attach_device_control_device(DeviceControlDevice const&);
bool is_console_device_attached() const { return !m_console_device.is_null(); }
void attach_console_device(ConsoleDevice const&);
void after_inserting_device(Badge<Device>, Device&);
void before_device_removal(Badge<Device>, Device&);
void for_each(Function<void(Device&)>);
ErrorOr<void> try_for_each(Function<ErrorOr<void>(Device&)>);
RefPtr<Device> get_device(MajorNumber major, MinorNumber minor);
NullDevice const& null_device() const;
NullDevice& null_device();
ConsoleDevice const& console_device() const;
ConsoleDevice& console_device();
template<typename DeviceType, typename... Args>
static inline ErrorOr<NonnullLockRefPtr<DeviceType>> try_create_device(Args&&... args)
requires(requires(Args... args) { DeviceType::try_create(args...); })
{
auto device = TRY(DeviceType::try_create(forward<Args>(args)...));
TRY(device->after_inserting());
return device;
}
template<typename DeviceType, typename... Args>
static inline ErrorOr<NonnullLockRefPtr<DeviceType>> try_create_device(Args&&... args)
{
auto device = TRY(adopt_nonnull_lock_ref_or_enomem(new (nothrow) DeviceType(forward<Args>(args)...)));
TRY(device->after_inserting());
return device;
}
SpinlockProtected<CircularQueue<DeviceEvent, 100>, LockRank::None>& event_queue(Badge<DeviceControlDevice>);
private:
LockRefPtr<NullDevice> m_null_device;
LockRefPtr<ConsoleDevice> m_console_device;
LockRefPtr<DeviceControlDevice> m_device_control_device;
SpinlockProtected<HashMap<u64, Device*>, LockRank::None> m_devices {};
SpinlockProtected<CircularQueue<DeviceEvent, 100>, LockRank::None> m_event_queue {};
};
}