write0() — netty Function Reference

Source Code

codec-classes-quic/src/main/java/io/netty/handler/codec/quic/QuicheQuicStreamChannel.java lines 831–890

        private int write0(Object msg) throws Exception {
            if (type() == QuicStreamType.UNIDIRECTIONAL && !isLocalCreated()) {
                throw new UnsupportedOperationException(
                        "Writes on non-local created streams that are unidirectional are not supported");
            }
            if (finSent) {
                throw new ChannelOutputShutdownException("Fin was sent already");
            }

            final boolean fin;
            ByteBuf buffer;
            if (msg instanceof ByteBuf) {
                fin = false;
                buffer = (ByteBuf) msg;
            } else {
                QuicStreamFrame frame = (QuicStreamFrame) msg;
                fin = frame.hasFin();
                buffer = frame.content();
            }

            boolean readable = buffer.isReadable();
            if (!fin && !readable) {
                return 1;
            }

            boolean sendSomething = false;
            try {
                do {
                    int res = parent().streamSend(streamId(), buffer, fin);

                    // Update the capacity as well.
                    long cap = parent.streamCapacity(streamId());
                    if (cap >= 0) {
                        capacity = cap;
                    }
                    if (res < 0) {
                        return res;
                    }
                    if (readable && res == 0) {
                        return 0;
                    }
                    sendSomething = true;
                    buffer.skipBytes(res);
                } while (buffer.isReadable());

                if (fin) {
                    finSent = true;
                    outputShutdown = true;
                }
                return 1;
            } finally {
                // As we called quiche_conn_stream_send(...) we need to ensure we will call quiche_conn_send(...) either
                // now or we will do so once we see the channelReadComplete event.
                //
                // See https://docs.rs/quiche/0.6.0/quiche/struct.Connection.html#method.send
                if (sendSomething) {
                    parent.connectionSendAndFlush();
                }
            }
        }