mirror of
https://github.com/LadybirdBrowser/ladybird.git
synced 2024-11-26 09:30:24 +00:00
286984750e
Now that support for 32-bit x86 has been removed, we don't have to worry about the top half of `off_t`/`u64` values being chopped off when we try to pass them in registers. Therefore, we no longer need the workaround of pointers to stack-allocated values to syscalls. Note that this changes the system call ABI, so statically linked programs will have to be re-linked.
116 lines
4 KiB
C++
116 lines
4 KiB
C++
/*
|
|
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
|
|
*
|
|
* SPDX-License-Identifier: BSD-2-Clause
|
|
*/
|
|
|
|
#include <AK/NumericLimits.h>
|
|
#include <Kernel/Debug.h>
|
|
#include <Kernel/FileSystem/OpenFileDescription.h>
|
|
#include <Kernel/Tasks/Process.h>
|
|
|
|
namespace Kernel {
|
|
|
|
ErrorOr<FlatPtr> Process::sys$pwritev(int fd, Userspace<const struct iovec*> iov, int iov_count, off_t base_offset)
|
|
{
|
|
VERIFY_PROCESS_BIG_LOCK_ACQUIRED(this);
|
|
TRY(require_promise(Pledge::stdio));
|
|
if (iov_count < 0)
|
|
return EINVAL;
|
|
|
|
if (iov_count > IOV_MAX)
|
|
return EFAULT;
|
|
|
|
u64 total_length = 0;
|
|
Vector<iovec, 32> vecs;
|
|
TRY(vecs.try_resize(iov_count));
|
|
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_file_description(fd));
|
|
if (!description->is_writable())
|
|
return EBADF;
|
|
// NOTE: Negative offset means "operate like writev" which seeks the file.
|
|
if (base_offset >= 0 && !description->file().is_seekable())
|
|
return EINVAL;
|
|
|
|
int nwritten = 0;
|
|
off_t current_offset = base_offset;
|
|
for (auto& vec : vecs) {
|
|
auto buffer = TRY(UserOrKernelBuffer::for_user_buffer((u8*)vec.iov_base, vec.iov_len));
|
|
auto result = do_write(*description, buffer, vec.iov_len, base_offset >= 0 ? current_offset : Optional<off_t> {});
|
|
if (result.is_error()) {
|
|
if (nwritten == 0)
|
|
return result.release_error();
|
|
return nwritten;
|
|
}
|
|
nwritten += result.value();
|
|
current_offset += result.value();
|
|
}
|
|
|
|
return nwritten;
|
|
}
|
|
|
|
ErrorOr<FlatPtr> Process::do_write(OpenFileDescription& description, UserOrKernelBuffer const& data, size_t data_size, Optional<off_t> offset)
|
|
{
|
|
size_t total_nwritten = 0;
|
|
|
|
if (description.should_append() && description.file().is_seekable()) {
|
|
TRY(description.seek(0, SEEK_END));
|
|
}
|
|
|
|
while (total_nwritten < data_size) {
|
|
while (!description.can_write()) {
|
|
if (!description.is_blocking()) {
|
|
if (total_nwritten > 0)
|
|
return total_nwritten;
|
|
return EAGAIN;
|
|
}
|
|
auto unblock_flags = Thread::FileBlocker::BlockFlags::None;
|
|
if (Thread::current()->block<Thread::WriteBlocker>({}, description, unblock_flags).was_interrupted()) {
|
|
if (total_nwritten == 0)
|
|
return EINTR;
|
|
}
|
|
// TODO: handle exceptions in unblock_flags
|
|
}
|
|
auto nwritten_or_error = offset.has_value()
|
|
? description.write(offset.value() + total_nwritten, data.offset(total_nwritten), data_size - total_nwritten)
|
|
: description.write(data.offset(total_nwritten), data_size - total_nwritten);
|
|
if (nwritten_or_error.is_error()) {
|
|
if (total_nwritten > 0)
|
|
return total_nwritten;
|
|
if (nwritten_or_error.error().code() == EAGAIN)
|
|
continue;
|
|
if (nwritten_or_error.error().code() == EPIPE)
|
|
Thread::current()->send_signal(SIGPIPE, &Process::current());
|
|
return nwritten_or_error.release_error();
|
|
}
|
|
VERIFY(nwritten_or_error.value() > 0);
|
|
total_nwritten += nwritten_or_error.value();
|
|
}
|
|
return total_nwritten;
|
|
}
|
|
|
|
ErrorOr<FlatPtr> Process::sys$write(int fd, Userspace<u8 const*> data, size_t size)
|
|
{
|
|
VERIFY_PROCESS_BIG_LOCK_ACQUIRED(this);
|
|
TRY(require_promise(Pledge::stdio));
|
|
if (size == 0)
|
|
return 0;
|
|
if (size > NumericLimits<ssize_t>::max())
|
|
return EINVAL;
|
|
|
|
dbgln_if(IO_DEBUG, "sys$write({}, {}, {})", fd, data.ptr(), size);
|
|
auto description = TRY(open_file_description(fd));
|
|
if (!description->is_writable())
|
|
return EBADF;
|
|
|
|
auto buffer = TRY(UserOrKernelBuffer::for_user_buffer(data, static_cast<size_t>(size)));
|
|
return do_write(*description, buffer, size);
|
|
}
|
|
|
|
}
|