jcs.org
Serenity Operating System
1/*
2 * Copyright (c) 2021, Andreas Kling <kling@serenityos.org>
3 *
4 * SPDX-License-Identifier: BSD-2-Clause
5 */
6
7#include <Kernel/FileSystem/AnonymousFile.h>
8#include <Kernel/FileSystem/OpenFileDescription.h>
9#include <Kernel/Memory/AnonymousVMObject.h>
10#include <Kernel/Process.h>
11
12namespace Kernel {
13
14ErrorOr<FlatPtr> Process::sys$anon_create(size_t size, int options)
15{
16 VERIFY_NO_PROCESS_BIG_LOCK(this);
17 TRY(require_promise(Pledge::stdio));
18
19 if (!size)
20 return EINVAL;
21
22 if (size % PAGE_SIZE)
23 return EINVAL;
24
25 if (size > NumericLimits<ssize_t>::max())
26 return EINVAL;
27
28 auto vmobject = TRY(Memory::AnonymousVMObject::try_create_purgeable_with_size(size, AllocationStrategy::AllocateNow));
29 auto anon_file = TRY(AnonymousFile::try_create(move(vmobject)));
30 auto description = TRY(OpenFileDescription::try_create(move(anon_file)));
31
32 description->set_writable(true);
33 description->set_readable(true);
34
35 u32 fd_flags = 0;
36 if (options & O_CLOEXEC)
37 fd_flags |= FD_CLOEXEC;
38
39 return m_fds.with_exclusive([&](auto& fds) -> ErrorOr<FlatPtr> {
40 auto new_fd = TRY(fds.allocate());
41 fds[new_fd.fd].set(description, fd_flags);
42 return new_fd.fd;
43 });
44}
45
46}