ladybird/Kernel/FileSystem/InodeMetadata.h
Tim Ledbetter ad984ba522 Kernel: Populate stat.st_dev with fsid
This allows userland programs to differentiate inodes on different
filesystems.
2023-10-01 13:34:41 +02:00

134 lines
4.7 KiB
C++

/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#pragma once
#include <AK/Error.h>
#include <AK/Span.h>
#include <AK/Time.h>
#include <Kernel/API/DeviceFileTypes.h>
#include <Kernel/FileSystem/InodeIdentifier.h>
#include <Kernel/Forward.h>
#include <Kernel/UnixTypes.h>
namespace Kernel {
class Process;
constexpr u64 encoded_device(MajorNumber major, MinorNumber minor)
{
return (minor.value() & 0xff) | (major.value() << 8) | ((minor.value() & ~0xff) << 12);
}
static inline MajorNumber major_from_encoded_device(dev_t dev) { return (dev & 0xfff00u) >> 8u; }
static inline MinorNumber minor_from_encoded_device(dev_t dev) { return (dev & 0xffu) | ((dev >> 12u) & 0xfff00u); }
inline bool is_directory(mode_t mode) { return (mode & S_IFMT) == S_IFDIR; }
inline bool is_character_device(mode_t mode) { return (mode & S_IFMT) == S_IFCHR; }
inline bool is_block_device(mode_t mode) { return (mode & S_IFMT) == S_IFBLK; }
inline bool is_regular_file(mode_t mode) { return (mode & S_IFMT) == S_IFREG; }
inline bool is_fifo(mode_t mode) { return (mode & S_IFMT) == S_IFIFO; }
inline bool is_symlink(mode_t mode) { return (mode & S_IFMT) == S_IFLNK; }
inline bool is_socket(mode_t mode) { return (mode & S_IFMT) == S_IFSOCK; }
inline bool is_sticky(mode_t mode) { return (mode & S_ISVTX) == S_ISVTX; }
inline bool is_setuid(mode_t mode) { return (mode & S_ISUID) == S_ISUID; }
inline bool is_setgid(mode_t mode) { return (mode & S_ISGID) == S_ISGID; }
enum class UseEffectiveIDs {
Yes,
No
};
struct InodeMetadata {
bool is_valid() const { return inode.is_valid(); }
bool may_read(Credentials const&, UseEffectiveIDs = UseEffectiveIDs::Yes) const;
bool may_write(Credentials const&, UseEffectiveIDs = UseEffectiveIDs::Yes) const;
bool may_execute(Credentials const&, UseEffectiveIDs = UseEffectiveIDs::Yes) const;
bool may_read(UserID u, GroupID g, ReadonlySpan<GroupID> eg) const
{
if (u == 0)
return true;
if (uid == u)
return (mode & S_IRUSR) == S_IRUSR;
if (gid == g || eg.contains_slow(gid))
return (mode & S_IRGRP) == S_IRGRP;
return (mode & S_IROTH) == S_IROTH;
}
bool may_write(UserID u, GroupID g, ReadonlySpan<GroupID> eg) const
{
if (u == 0)
return true;
if (uid == u)
return (mode & S_IWUSR) == S_IWUSR;
if (gid == g || eg.contains_slow(gid))
return (mode & S_IWGRP) == S_IWGRP;
return (mode & S_IWOTH) == S_IWOTH;
}
bool may_execute(UserID u, GroupID g, ReadonlySpan<GroupID> eg) const
{
if (u == 0)
return true;
if (uid == u)
return (mode & S_IXUSR) == S_IXUSR;
if (gid == g || eg.contains_slow(gid))
return (mode & S_IXGRP) == S_IXGRP;
return (mode & S_IXOTH) == S_IXOTH;
}
bool is_directory() const { return Kernel::is_directory(mode); }
bool is_character_device() const { return Kernel::is_character_device(mode); }
bool is_block_device() const { return Kernel::is_block_device(mode); }
bool is_device() const { return is_character_device() || is_block_device(); }
bool is_regular_file() const { return Kernel::is_regular_file(mode); }
bool is_fifo() const { return Kernel::is_fifo(mode); }
bool is_symlink() const { return Kernel::is_symlink(mode); }
bool is_socket() const { return Kernel::is_socket(mode); }
bool is_sticky() const { return Kernel::is_sticky(mode); }
bool is_setuid() const { return Kernel::is_setuid(mode); }
bool is_setgid() const { return Kernel::is_setgid(mode); }
ErrorOr<struct stat> stat() const
{
if (!is_valid())
return EIO;
struct stat buffer = {};
buffer.st_rdev = encoded_device(major_device, minor_device);
buffer.st_ino = inode.index().value();
buffer.st_mode = mode;
buffer.st_nlink = link_count;
buffer.st_uid = uid.value();
buffer.st_gid = gid.value();
buffer.st_dev = inode.fsid().value();
buffer.st_size = size;
buffer.st_blksize = block_size;
buffer.st_blocks = block_count;
buffer.st_atim = atime.to_timespec();
buffer.st_mtim = mtime.to_timespec();
buffer.st_ctim = ctime.to_timespec();
return buffer;
}
InodeIdentifier inode;
off_t size { 0 };
mode_t mode { 0 };
UserID uid { 0 };
GroupID gid { 0 };
nlink_t link_count { 0 };
UnixDateTime atime {};
UnixDateTime ctime {};
UnixDateTime mtime {};
UnixDateTime dtime {};
blkcnt_t block_count { 0 };
blksize_t block_size { 0 };
MajorNumber major_device { 0 };
MinorNumber minor_device { 0 };
};
}