mirror of
https://github.com/LadybirdBrowser/ladybird.git
synced 2025-06-06 02:12:52 +00:00
79fa9765ca
We now use AK::Error and AK::ErrorOr<T> in both kernel and userspace! This was a slightly tedious refactoring that took a long time, so it's not unlikely that some bugs crept in. Nevertheless, it does pass basic functionality testing, and it's just real nice to finally see the same pattern in all contexts. :^)
115 lines
3.6 KiB
C++
115 lines
3.6 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 {
|
|
|
|
using BlockFlags = Thread::FileBlocker::BlockFlags;
|
|
|
|
static ErrorOr<OpenFileDescription*> open_readable_file_description(Process::OpenFileDescriptions const& fds, int fd)
|
|
{
|
|
auto description = TRY(fds.open_file_description(fd));
|
|
if (!description->is_readable())
|
|
return EBADF;
|
|
if (description->is_directory())
|
|
return EISDIR;
|
|
return description;
|
|
}
|
|
|
|
static ErrorOr<void> check_blocked_read(OpenFileDescription* description)
|
|
{
|
|
if (description->is_blocking()) {
|
|
if (!description->can_read()) {
|
|
auto unblock_flags = BlockFlags::None;
|
|
if (Thread::current()->block<Thread::ReadBlocker>({}, *description, unblock_flags).was_interrupted())
|
|
return EINTR;
|
|
if (!has_flag(unblock_flags, BlockFlags::Read))
|
|
return EAGAIN;
|
|
// TODO: handle exceptions in unblock_flags
|
|
}
|
|
}
|
|
return {};
|
|
}
|
|
|
|
ErrorOr<FlatPtr> Process::sys$readv(int fd, Userspace<const struct iovec*> iov, int iov_count)
|
|
{
|
|
VERIFY_PROCESS_BIG_LOCK_ACQUIRED(this)
|
|
REQUIRE_PROMISE(stdio);
|
|
if (iov_count < 0)
|
|
return EINVAL;
|
|
|
|
// Arbitrary pain threshold.
|
|
if (iov_count > (int)MiB)
|
|
return EFAULT;
|
|
|
|
u64 total_length = 0;
|
|
Vector<iovec, 32> vecs;
|
|
if (!vecs.try_resize(iov_count))
|
|
return ENOMEM;
|
|
TRY(copy_n_from_user(vecs.data(), iov, iov_count));
|
|
for (auto& vec : vecs) {
|
|
total_length += vec.iov_len;
|
|
if (total_length > NumericLimits<i32>::max())
|
|
return EINVAL;
|
|
}
|
|
|
|
auto description = TRY(open_readable_file_description(fds(), fd));
|
|
|
|
int nread = 0;
|
|
for (auto& vec : vecs) {
|
|
TRY(check_blocked_read(description));
|
|
auto buffer = UserOrKernelBuffer::for_user_buffer((u8*)vec.iov_base, vec.iov_len);
|
|
if (!buffer.has_value())
|
|
return EFAULT;
|
|
auto nread_here = TRY(description->read(buffer.value(), vec.iov_len));
|
|
nread += nread_here;
|
|
}
|
|
|
|
return nread;
|
|
}
|
|
|
|
ErrorOr<FlatPtr> Process::sys$read(int fd, Userspace<u8*> buffer, size_t size)
|
|
{
|
|
VERIFY_PROCESS_BIG_LOCK_ACQUIRED(this)
|
|
REQUIRE_PROMISE(stdio);
|
|
if (size == 0)
|
|
return 0;
|
|
if (size > NumericLimits<ssize_t>::max())
|
|
return EINVAL;
|
|
dbgln_if(IO_DEBUG, "sys$read({}, {}, {})", fd, buffer.ptr(), size);
|
|
auto description = TRY(open_readable_file_description(fds(), fd));
|
|
TRY(check_blocked_read(description));
|
|
auto user_buffer = UserOrKernelBuffer::for_user_buffer(buffer, size);
|
|
if (!user_buffer.has_value())
|
|
return EFAULT;
|
|
return TRY(description->read(user_buffer.value(), size));
|
|
}
|
|
|
|
ErrorOr<FlatPtr> Process::sys$pread(int fd, Userspace<u8*> buffer, size_t size, off_t offset)
|
|
{
|
|
VERIFY_PROCESS_BIG_LOCK_ACQUIRED(this)
|
|
REQUIRE_PROMISE(stdio);
|
|
if (size == 0)
|
|
return 0;
|
|
if (size > NumericLimits<ssize_t>::max())
|
|
return EINVAL;
|
|
if (offset < 0)
|
|
return EINVAL;
|
|
dbgln_if(IO_DEBUG, "sys$pread({}, {}, {}, {})", fd, buffer.ptr(), size, offset);
|
|
auto description = TRY(open_readable_file_description(fds(), fd));
|
|
if (!description->file().is_seekable())
|
|
return EINVAL;
|
|
TRY(check_blocked_read(description));
|
|
auto user_buffer = UserOrKernelBuffer::for_user_buffer(buffer, size);
|
|
if (!user_buffer.has_value())
|
|
return EFAULT;
|
|
return TRY(description->read(user_buffer.value(), offset, size));
|
|
}
|
|
|
|
}
|