ladybird/Kernel/Syscalls/fcntl.cpp
Brian Gianforcaro bad6d50b86 Kernel: Use Process::require_promise() instead of REQUIRE_PROMISE()
This change lays the foundation for making the require_promise return
an error hand handling the process abort outside of the syscall
implementations, to avoid cases where we would leak resources.

It also has the advantage that it makes removes a gs pointer read
to look up the current thread, then process for every syscall. We
can instead go through the Process this pointer in most cases.
2021-12-29 18:08:15 +01:00

55 lines
1.5 KiB
C++

/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <Kernel/Debug.h>
#include <Kernel/FileSystem/OpenFileDescription.h>
#include <Kernel/Process.h>
namespace Kernel {
ErrorOr<FlatPtr> Process::sys$fcntl(int fd, int cmd, u32 arg)
{
VERIFY_PROCESS_BIG_LOCK_ACQUIRED(this);
require_promise(Pledge::stdio);
dbgln_if(IO_DEBUG, "sys$fcntl: fd={}, cmd={}, arg={}", fd, cmd, arg);
auto description = TRY(fds().open_file_description(fd));
// NOTE: The FD flags are not shared between OpenFileDescription objects.
// This means that dup() doesn't copy the FD_CLOEXEC flag!
switch (cmd) {
case F_DUPFD: {
int arg_fd = (int)arg;
if (arg_fd < 0)
return EINVAL;
auto fd_allocation = TRY(m_fds.allocate(arg_fd));
m_fds[fd_allocation.fd].set(*description);
return fd_allocation.fd;
}
case F_GETFD:
return m_fds[fd].flags();
case F_SETFD:
m_fds[fd].set_flags(arg);
break;
case F_GETFL:
return description->file_flags();
case F_SETFL:
description->set_file_flags(arg);
break;
case F_ISTTY:
return description->is_tty();
case F_GETLK:
TRY(description->get_flock(Userspace<flock*>(arg)));
return 0;
case F_SETLK:
TRY(description->apply_flock(Process::current(), Userspace<const flock*>(arg)));
return 0;
default:
return EINVAL;
}
return 0;
}
}