ladybird/Kernel/Syscalls/lseek.cpp

24 lines
658 B
C++

/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <Kernel/FileSystem/OpenFileDescription.h>
#include <Kernel/Tasks/Process.h>
namespace Kernel {
ErrorOr<FlatPtr> Process::sys$lseek(int fd, Userspace<off_t*> userspace_offset, int whence)
{
VERIFY_NO_PROCESS_BIG_LOCK(this);
TRY(require_promise(Pledge::stdio));
auto description = TRY(open_file_description(fd));
off_t offset;
TRY(copy_from_user(&offset, userspace_offset));
auto seek_result = TRY(description->seek(offset, whence));
TRY(copy_to_user(userspace_offset, &seek_result));
return 0;
}
}