Re: message handling

You must send a RPY or an ANS/NUL sequence.  It is the correct behavior
not to process the next MSG before the previous message is completed.

-bill

On Tue, Jul 05, 2005 at 05:17:49PM +0200, Daan Hoogland wrote:
> LS,
> 
> A collegue of mine wrote a patch to beepcore-java's ChannelImpl. The
> issue we had was that it was not possible to not reply to a message and
> then send a second message from the same peer. The specifications say
> that it should be possible to send zero (or more) replies, so we felt
> this patch was legal. Any ideas anybody?
> 
> -- 
> <insert value="your favorite astute quote" id="sigquote" />
> -----------------------------
> Daan Hoogland
> software architect
> -----------------------------
> [email protected]
> 0620442544
> www.luminis.nl
> -----------------------------
> <or ref="sigquote" />
> 

> diff -ur beepcore-0.9.08/src/org/beepcore/beep/core/ChannelImpl.java beepcore/src/org/beepcore/beep/core/ChannelImpl.java
> --- beepcore-0.9.08/src/org/beepcore/beep/core/ChannelImpl.java	2003-11-18 08:28:46.000000000 +0100
> +++ beepcore/src/org/beepcore/beep/core/ChannelImpl.java	2005-07-05 14:58:31.000000000 +0200
> @@ -351,17 +351,36 @@
>          return this.session;
>      }
>  
> -    public void run() {
> -        MessageMSGImpl m;
> -        synchronized (recvMSGQueue) {
> -                m = (MessageMSGImpl) recvMSGQueue.getFirst();
> -                synchronized (m) {
> -                    m.setNotified();
> -                }
> -        }
> -
> -        handler.receiveMSG(m);
> -    }
> +     /**
> +      * Handles first unnotified message in received-message-queue by delivering it to the current
> +      * request handler. The message is set notified. If the queue is empty, or all messages are 
> +      * already notified, nothing is done.   
> +      */
> +      public void run() {
> +          boolean messageFound = false;
> +          MessageMSGImpl message = null;
> +          // find unnotified message
> +          synchronized (recvMSGQueue) {
> +              for (Iterator messageIter = recvMSGQueue.iterator(); messageIter.hasNext();) {
> +                  MessageMSGImpl currentMessage  = (MessageMSGImpl) messageIter.next();
> +                  // if message has not been handled yet
> +                  if (!currentMessage.isNotified()) {
> +                      currentMessage.setNotified();
> +                      message = currentMessage;
> +                      messageFound = true;
> +                      break;
> +                  }
> +              }
> +          }
> +          // deliver message to request handler if unnotified message has been found
> +          if (messageFound) 
> +              handler.receiveMSG(message);
> +          else 
> +              log.warn("All messages in queue has already been delivered to the request handler");
> +     }
> +    
> +    
> +    
>  
>      /**
>       * Sends a message of type MSG.
> @@ -485,10 +504,12 @@
>                      m = (MessageMSGImpl) recvMSGQueue.getLast();
>  
>                      if (m.getMsgno() != frame.getMsgno()) {
> +                        // frame does not belong to previous message
>                          m = null;
>                      }
>                  }
>  
> +                // if frame belongs to previous message
>                  if (m != null) {
>                      /// Move this code to DataStream...
>                      Iterator i = frame.getPayload();
> @@ -504,24 +525,42 @@
>                      
>                      return;
>                  }
> -
> +                // else if frame does not belong to previous message 
>                  m = new MessageMSGImpl(this, frame.getMsgno(),
>                                         new InputDataStream(this));
>  
> -                m.setNotified();
> +                // assumption: 
> +                //      notified message means message has been delivered to request handler
> +                // change: 
> +                //      disabled statement below and notify message only after it has been 
> +                //      retreived from the queue for delivery to the request handler, see run() 
> +                //      method
> +                
> +                // m.setNotified();
>  
>                  Iterator i = frame.getPayload();
>                  while (i.hasNext()) {
>                      m.getDataStream().add((BufferSegment)i.next());
>                  }
>  
> +                // if frame is last (and here also first!): frame contains complete message
>                  if (frame.isLast()) {
>                      m.getDataStream().setComplete();
>                  }
> -
> +                
>                  recvMSGQueue.addLast(m);
>                  
> -                if (recvMSGQueue.size() == 1) {
> +                // assumption: 
> +                //      received-message-queue can contain several messages since a message 
> +                //      is only removed if it is of type MESSAGE_TYPE_RPY, MESSAGE_TYPE_ERR or 
> +                //      MESSAGE_TYPE_NUL. Messages of type MESSAGE_TYPE_MSG will never be removed 
> +                //      from the queue.
> +                // change: 
> +                //      changed statement 'if (recvMSGQueue.size() == 1) {' into
> +                //      'if (recvMSGQueue.size() > 0) {'
> +                
> +                // if message queue contains at least 1 message
> +                if (recvMSGQueue.size() > 0) {
>                      try {
>                          callbackQueue.execute(this);
>                      } catch (InterruptedException e) {



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