ladybird/Kernel/Syscalls/open.cpp
Andreas Kling ac71775de5 Kernel: Make all syscall functions return KResultOr<T>
This makes it a lot easier to return errors since we no longer have to
worry about negating EFOO errors and can just return them flat.
2021-03-01 13:54:32 +01:00

111 lines
3.6 KiB
C++

/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <Kernel/Debug.h>
#include <Kernel/FileSystem/Custody.h>
#include <Kernel/FileSystem/FileDescription.h>
#include <Kernel/FileSystem/VirtualFileSystem.h>
#include <Kernel/Process.h>
namespace Kernel {
KResultOr<int> Process::sys$open(Userspace<const Syscall::SC_open_params*> user_params)
{
Syscall::SC_open_params params;
if (!copy_from_user(&params, user_params))
return EFAULT;
int dirfd = params.dirfd;
int options = params.options;
u16 mode = params.mode;
if (options & O_NOFOLLOW_NOERROR)
return EINVAL;
if (options & O_UNLINK_INTERNAL)
return EINVAL;
if (options & O_WRONLY)
REQUIRE_PROMISE(wpath);
else if (options & O_RDONLY)
REQUIRE_PROMISE(rpath);
if (options & O_CREAT)
REQUIRE_PROMISE(cpath);
// Ignore everything except permission bits.
mode &= 0777;
auto path = get_syscall_path_argument(params.path);
if (path.is_error())
return path.error();
dbgln_if(IO_DEBUG, "sys$open(dirfd={}, path='{}', options={}, mode={})", dirfd, path.value(), options, mode);
int fd = alloc_fd();
if (fd < 0)
return fd;
RefPtr<Custody> base;
if (dirfd == AT_FDCWD) {
base = current_directory();
} else {
auto base_description = file_description(dirfd);
if (!base_description)
return EBADF;
if (!base_description->is_directory())
return ENOTDIR;
if (!base_description->custody())
return EINVAL;
base = base_description->custody();
}
auto result = VFS::the().open(path.value(), options, mode & ~umask(), *base);
if (result.is_error())
return result.error();
auto description = result.value();
if (description->inode() && description->inode()->socket())
return ENXIO;
u32 fd_flags = (options & O_CLOEXEC) ? FD_CLOEXEC : 0;
m_fds[fd].set(move(description), fd_flags);
return fd;
}
KResultOr<int> Process::sys$close(int fd)
{
REQUIRE_PROMISE(stdio);
auto description = file_description(fd);
dbgln_if(IO_DEBUG, "sys$close({}) {}", fd, description.ptr());
if (!description)
return EBADF;
int rc = description->close();
m_fds[fd] = {};
return rc;
}
}