recvmsgComplete() — netty Function Reference

Source Code

transport-classes-io_uring/src/main/java/io/netty/channel/uring/IoUringDatagramChannel.java lines 422–469

        private void recvmsgComplete(ChannelPipeline pipeline, IoUringRecvByteAllocatorHandle allocHandle,
                                      ByteBuf byteBuf, int res, int flags, int idx, int outstanding)
                throws IOException {
            MsgHdrMemory hdr = recvmsgHdrs.hdr(idx);
            if (res < 0) {
                if (res != Native.ERRNO_ECANCELED_NEGATIVE) {
                    // If res is negative we should pass it to ioResult(...) which will either throw
                    // or convert it to 0 if we could not read because the socket was not readable.
                    allocHandle.lastBytesRead(ioResult("io_uring recvmsg", res));
                }
            } else {
                allocHandle.lastBytesRead(res);
                if (hdr.hasPort(IoUringDatagramChannel.this)) {
                    allocHandle.incMessagesRead(1);
                    DatagramPacket packet = hdr.get(
                            IoUringDatagramChannel.this, registration().attachment(), byteBuf, res);
                    pipeline.fireChannelRead(packet);
                }
            }

            // Reset the id as this read was completed and so don't need to be cancelled later.
            recvmsgHdrs.setId(idx, MsgHdrMemoryArray.NO_ID);
            if (outstanding == 0) {
                // There are no outstanding completion events, release the readBuffer and see if we need to schedule
                // another one or if the user will do it.
                this.readBuffer.release();
                this.readBuffer = null;
                recvmsgHdrs.clear();

                if (res != Native.ERRNO_ECANCELED_NEGATIVE) {
                    if (allocHandle.lastBytesRead() > 0 &&
                            allocHandle.continueReading(UncheckedBooleanSupplier.TRUE_SUPPLIER) &&
                            // If IORING_CQE_F_SOCK_NONEMPTY is supported we should check for it first before
                            // trying to schedule a read. If it's supported and not part of the flags we know for sure
                            // that the next read (which would be using Native.MSG_DONTWAIT) will complete without
                            // be able to read any data. This is useless work and we can skip it.
                            (!IoUring.isCqeFSockNonEmptySupported() ||
                                    (flags & Native.IORING_CQE_F_SOCK_NONEMPTY) != 0)) {
                        // Let's schedule another read.
                        scheduleRead(false);
                    } else {
                        // the read was completed with EAGAIN.
                        allocHandle.readComplete();
                        pipeline.fireChannelReadComplete();
                    }
                }
            }
        }