ladybird/Kernel/Devices/Device.h
Jesse 401c87a0cc Kernel: mount system call (#396)
It is now possible to mount ext2 `DiskDevice` devices under Serenity on
any folder in the root filesystem. Currently any user can do this with
any permissions. There's a fair amount of assumptions made here too,
that might not be too good, but can be worked on in the future. This is
a good start to allow more dynamic operation under the OS itself.

It is also currently impossible to unmount and such, and devices will
fail to mount in Linux as the FS 'needs to be cleaned'. I'll work on
getting `umount` done ASAP to rectify this (as well as working on less
assumption-making in the mount syscall. We don't want to just be able
to mount DiskDevices!). This could probably be fixed with some `-t`
flag or something similar.
2019-08-02 15:18:47 +02:00

41 lines
1.1 KiB
C++

#pragma once
// Device is the base class of everything that lives in the /dev directory.
//
// All Devices will automatically register with the VFS.
// To expose a Device to the filesystem, simply pass two unique numbers to the constructor,
// and then mknod a file in /dev with those numbers.
//
// There are two main subclasses:
// - BlockDevice (random access)
// - CharacterDevice (sequential)
#include <Kernel/FileSystem/File.h>
#include <Kernel/UnixTypes.h>
class Device : public File {
public:
virtual ~Device() override;
unsigned major() const { return m_major; }
unsigned minor() const { return m_minor; }
virtual String absolute_path(const FileDescription&) const override;
uid_t uid() const { return m_uid; }
uid_t gid() const { return m_gid; }
virtual bool is_device() const override { return true; }
virtual bool is_disk_device() const { return false; }
protected:
Device(unsigned major, unsigned minor);
void set_uid(uid_t uid) { m_uid = uid; }
void set_gid(gid_t gid) { m_gid = gid; }
private:
unsigned m_major { 0 };
unsigned m_minor { 0 };
uid_t m_uid { 0 };
gid_t m_gid { 0 };
};