ladybird/Kernel/Syscalls/stat.cpp
Liav A 7c87891c06 Kernel: Don't copy a Vector<FileDescriptionAndFlags>
Instead of copying a Vector everytime we need to enumerate a Process'
file descriptions, we can just temporarily lock so it won't change.
2021-06-29 20:53:59 +02:00

63 lines
1.8 KiB
C++

/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <AK/NonnullRefPtrVector.h>
#include <Kernel/FileSystem/Custody.h>
#include <Kernel/FileSystem/FileDescription.h>
#include <Kernel/FileSystem/VirtualFileSystem.h>
#include <Kernel/Process.h>
namespace Kernel {
KResultOr<FlatPtr> Process::sys$fstat(int fd, Userspace<stat*> user_statbuf)
{
REQUIRE_PROMISE(stdio);
auto description = fds().file_description(fd);
if (!description)
return EBADF;
stat buffer = {};
int rc = description->stat(buffer);
if (!copy_to_user(user_statbuf, &buffer))
return EFAULT;
return rc;
}
KResultOr<FlatPtr> Process::sys$stat(Userspace<const Syscall::SC_stat_params*> user_params)
{
REQUIRE_PROMISE(rpath);
Syscall::SC_stat_params params;
if (!copy_from_user(&params, user_params))
return EFAULT;
auto path = get_syscall_path_argument(params.path);
if (path.is_error())
return path.error();
RefPtr<Custody> base;
if (params.dirfd == AT_FDCWD) {
base = current_directory();
} else {
auto base_description = fds().file_description(params.dirfd);
if (!base_description)
return EBADF;
if (!base_description->is_directory())
return ENOTDIR;
if (!base_description->custody())
return EINVAL;
base = base_description->custody();
}
auto metadata_or_error = VFS::the().lookup_metadata(path.value()->view(), *base, params.follow_symlinks ? 0 : O_NOFOLLOW_NOERROR);
if (metadata_or_error.is_error())
return metadata_or_error.error();
stat statbuf;
auto result = metadata_or_error.value().stat(statbuf);
if (result.is_error())
return result;
if (!copy_to_user(params.statbuf, &statbuf))
return EFAULT;
return 0;
}
}