void AsyncPipeWriter::handleWrite() {
DestructorGuard dg(this);
assert(!queue_.empty());
do {
auto& front = queue_.front();
folly::IOBufQueue& curQueue = front.first;
DCHECK(!curQueue.empty());
// someday, support writev. The logic for partial writes is a bit complex
const IOBuf* head = curQueue.front();
CHECK(head->length());
#if _WIN32
// On Windows you can't call write on a socket.
ssize_t rc = folly::fileutil_detail::wrapNoInt(
send_internal, fd_, head->data(), head->length());
#else
ssize_t rc = folly::writeNoInt(fd_.toFd(), head->data(), head->length());
#endif
if (rc < 0) {
if (errno == EAGAIN || errno == EWOULDBLOCK) {
// pipe is full
VLOG(5) << "write blocked";
registerHandler(EventHandler::WRITE);
return;
} else {
failAllWrites(AsyncSocketException(
AsyncSocketException::INTERNAL_ERROR, "write failed", errno));
closeNow();
return;
}
} else if (rc == 0) {
registerHandler(EventHandler::WRITE);
return;
}
curQueue.trimStart(size_t(rc));
if (curQueue.empty()) {
auto cb = front.second;
queue_.pop_front();
if (cb) {
cb->writeSuccess();
}
} else {
VLOG(5) << "partial write blocked";
}
} while (!queue_.empty());
if (closeOnEmpty_) {
closeNow();
} else {
unregisterHandler();
}
}
// Low level interface
void Cpp2Channel::sendMessage(SendCallback* callback,
std::unique_ptr<folly::IOBuf>&& buf) {
// Callback may be null.
assert(buf);
if (!transport_->good()) {
VLOG(5) << "Channel is !good() in sendMessage";
// Callback must be last thing in sendMessage, or use guard
if (callback) {
callback->messageSendError(
folly::make_exception_wrapper<TTransportException>(
"Channel is !good()"));
}
return;
}
std::vector<SendCallback*> cbs;
if (callback) {
callback->sendQueued();
cbs.push_back(callback);
}
sendCallbacks_.push_back(std::move(cbs));
DestructorGuard dg(this);
auto future = pipeline_->write(std::move(buf));
future.then([this,dg](folly::Try<void>&& t) {
if (t.withException<TTransportException>(
[&](const TTransportException& ex) {
writeError(0, ex);
}) ||
t.withException<std::exception>(
[&](const std::exception& ex) {
writeError(0, TTransportException(ex.what()));
})) {
return;
}
else {
writeSuccess();
}
});
}