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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
#include "Win32SerialParityCheckStream.h"
#include <windows.h>
#include "SerialLogging.h"
#include "nsError.h"
#include "nsStreamUtils.h"
namespace mozilla::dom {
NS_IMPL_ISUPPORTS(Win32SerialParityCheckStream, nsIInputStream,
nsIAsyncInputStream)
Win32SerialParityCheckStream::Win32SerialParityCheckStream(
nsCOMPtr<nsIAsyncInputStream> aInner, UniqueFileHandle aCommHandle)
: mInner(std::move(aInner)), mCommHandle(std::move(aCommHandle)) {
MOZ_ASSERT(mCommHandle);
}
void Win32SerialParityCheckStream::CheckForParityError() {
if (MOZ_UNLIKELY(mParityErrorLatched)) {
return;
}
DWORD errors = 0;
if (ClearCommError(mCommHandle.get(), &errors, nullptr) &&
(errors & CE_RXPARITY)) {
MOZ_LOG(gWebSerialLog, LogLevel::Debug,
("Win32SerialParityCheckStream[%p] detected CE_RXPARITY", this));
mParityErrorLatched = true;
}
}
NS_IMETHODIMP Win32SerialParityCheckStream::ReadSegments(
nsWriteSegmentFun aWriter, void* aClosure, uint32_t aCount,
uint32_t* aResult) {
*aResult = 0;
if (MOZ_UNLIKELY(mParityErrorLatched)) {
return NS_ERROR_DOM_SERIAL_PARITY_ERROR;
}
nsresult rv = mInner->ReadSegments(aWriter, aClosure, aCount, aResult);
if (NS_SUCCEEDED(rv)) {
// If there is a parity error, record it so we can return it next time.
// We do this instead of returning the error now to avoid a confusing
// return from ReadSegments() that would return data but also an error.
CheckForParityError();
}
return rv;
}
NS_IMETHODIMP Win32SerialParityCheckStream::Read(char* aBuf, uint32_t aCount,
uint32_t* aResult) {
return ReadSegments(NS_CopySegmentToBuffer, aBuf, aCount, aResult);
}
NS_IMETHODIMP Win32SerialParityCheckStream::Available(uint64_t* aResult) {
if (MOZ_UNLIKELY(mParityErrorLatched)) {
return NS_ERROR_DOM_SERIAL_PARITY_ERROR;
}
return mInner->Available(aResult);
}
NS_IMETHODIMP Win32SerialParityCheckStream::StreamStatus() {
if (MOZ_UNLIKELY(mParityErrorLatched)) {
return NS_ERROR_DOM_SERIAL_PARITY_ERROR;
}
return mInner->StreamStatus();
}
NS_IMETHODIMP Win32SerialParityCheckStream::Close() { return mInner->Close(); }
NS_IMETHODIMP Win32SerialParityCheckStream::IsNonBlocking(bool* aResult) {
return mInner->IsNonBlocking(aResult);
}
NS_IMETHODIMP Win32SerialParityCheckStream::CloseWithStatus(nsresult aStatus) {
return mInner->CloseWithStatus(aStatus);
}
NS_IMETHODIMP Win32SerialParityCheckStream::AsyncWait(
nsIInputStreamCallback* aCallback, uint32_t aFlags,
uint32_t aRequestedCount, nsIEventTarget* aTarget) {
// We never buffer and never return WOULD_BLOCK while a parity error is
// latched (ReadSegments returns the error directly), so delegating the wait
// to the inner stream always wakes the consumer at the right time.
return mInner->AsyncWait(aCallback, aFlags, aRequestedCount, aTarget);
}
} // namespace mozilla::dom