Open Mash Cross Reference
mash/tcl/net/relay.tcl

   
   # Copyright (c) 2003 The Regents of the University of California.
   # All rights reserved.
   #
   # Redistribution and use in source and binary forms, with or without
   # modification, are permitted provided that the following conditions are met:
   #
   # A. Redistributions of source code must retain the above copyright notice,
   #    this list of conditions and the following disclaimer.
  # B. Redistributions in binary form must reproduce the above copyright notice,
  #    this list of conditions and the following disclaimer in the documentation
  #    and/or other materials provided with the distribution.
  # C. Neither the names of the copyright holders nor the names of its
  #    contributors may be used to endorse or promote products derived from this
  #    software without specific prior written permission.
  #
  # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS''
  # AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  # IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  # ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR
  # ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  # DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  # SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  # CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  # OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  #
  # @(#) $Header: /usr/mash/src/repository/mash/mash-1/tcl/net/relay.tcl,v 1.1 2003/06/03 20:06:46 aswan Exp $
  
  
  #
  # RelayedNetwork and RelayedNetPort are split classes
  # defined mostly in C++.  They provide a simple way to
  # implement application-level (or peer-to-peer) multicast.
  # The RelayedNetwork class can be used in exactly the
  # same way as the NetworkManager class that joins an
  # rtp (or ssm, etc.) session via regular IPv4 UDP sockets.
  #
  # These classes provide the basic packet forwarding
  # services needed for application-level multicast but
  # no particular policy for constructing an
  # application-level multicast tree.  Such logic must
  # be implemented in a subclass of RelayedNetwork.
  # For an example, see the RelayedNetwork/Simple class
  # in which the multicast tree is statically specified
  # by the user when the application is run.
  #
  # XXX caveat hacker
  # This code is likely to change dramatically so don't
  # make any assumptions about the packet formats or
  # programming interfaces remaining as they are now...
  #
  
  RelayedNetPort instproc init { network portno } {
          $self next
          $self setup $network $portno
  }
  
  RelayedNetwork instproc init { spec session agent } {
          $self instvar session_ agent_ nchan_ data_port_ ctrl_port_
  
          $self next
          set session_ $session
          set agent_ $agent
  
          #XXX
          set nchan_ 1
          $agent_ set_maxchannel 1
  
          $self reset $spec
  
          for { set i 0 } { $i < $nchan_ } { incr i } {
                  set p [new RelayedNetPort $self [expr 2*$i]]
                  set data_port_($i) $p
                  $session_ data-net $p $i
  
                  set p [new RelayedNetPort $self [expr 2*$i + 1]]
                  set ctrl_port_($i) $p
                  $session_ ctrl-net $p $i
          }
  }
  
  RelayedNetwork instproc data-net args {
          if { $args == "" } {
                  set k 0
          } else {
                  set k $args
          }
          
          $self instvar data_port_
          return $data_port_($k)
  }
  
  RelayedNetwork instproc ctrl-net args {
          if { $args == "" } {
                  set k 0
          } else {
                  set k $args
          }
         
         $self instvar ctrl_port_
         return $ctrl_port_($k)
 }
 
 RelayedNetwork instproc set-subscription-level args {
         #XXX
 }
 
 RelayedNetwork instproc install-key key {
         #XXX
 }
 
 
 RelayedNetwork instproc usingRLM {} {
         return 0
 }
 
 RelayedNetwork instproc nchan {} {
         return [$self set nchan_]
 }
 
 RelayedNetwork instproc ismulticast {} {
         return 1
 }