updateSendWindowSize() — netty Function Reference

Source Code

codec-http/src/main/java/io/netty/handler/codec/spdy/SpdySessionHandler.java lines 744–798

    private void updateSendWindowSize(final ChannelHandlerContext ctx, int streamId, int deltaWindowSize) {
        spdySession.updateSendWindowSize(streamId, deltaWindowSize);

        while (true) {
            // Check if we have unblocked a stalled stream
            SpdySession.PendingWrite pendingWrite = spdySession.getPendingWrite(streamId);
            if (pendingWrite == null) {
                return;
            }

            SpdyDataFrame spdyDataFrame = pendingWrite.spdyDataFrame;
            int dataFrameSize = spdyDataFrame.content().readableBytes();
            int writeStreamId = spdyDataFrame.streamId();
            int sendWindowSize = spdySession.getSendWindowSize(writeStreamId);
            int sessionSendWindowSize = spdySession.getSendWindowSize(SPDY_SESSION_STREAM_ID);
            sendWindowSize = Math.min(sendWindowSize, sessionSendWindowSize);

            if (sendWindowSize <= 0) {
                return;
            } else if (sendWindowSize < dataFrameSize) {
                // We can send a partial frame
                spdySession.updateSendWindowSize(writeStreamId, -1 * sendWindowSize);
                spdySession.updateSendWindowSize(SPDY_SESSION_STREAM_ID, -1 * sendWindowSize);

                // Create a partial data frame whose length is the current window size
                SpdyDataFrame partialDataFrame = new DefaultSpdyDataFrame(
                        writeStreamId, spdyDataFrame.content().readRetainedSlice(sendWindowSize));

                // The transfer window size is pre-decremented when sending a data frame downstream.
                ctx.writeAndFlush(partialDataFrame).addListener(future -> {
                    if (!future.isSuccess()) {
                        issueSessionError(ctx, SpdySessionStatus.INTERNAL_ERROR);
                    }
                });
            } else {
                // Window size is large enough to send entire data frame
                spdySession.removePendingWrite(writeStreamId);
                spdySession.updateSendWindowSize(writeStreamId, -1 * dataFrameSize);
                spdySession.updateSendWindowSize(SPDY_SESSION_STREAM_ID, -1 * dataFrameSize);

                // Close the local side of the stream if this is the last frame
                if (spdyDataFrame.isLast()) {
                    halfCloseStream(writeStreamId, false, pendingWrite.promise);
                }

                // The transfer window size is pre-decremented when sending a data frame downstream.
                // Close the session on write failures that leave the transfer window in a corrupt state.
                ctx.writeAndFlush(spdyDataFrame, pendingWrite.promise).addListener(future -> {
                    if (!future.isSuccess()) {
                        issueSessionError(ctx, SpdySessionStatus.INTERNAL_ERROR);
                    }
                });
            }
        }
    }