Open Mash Cross Reference
mash/tcl/indiva/lib/ascp-service.tcl

   # ascp-service.tcl --

   #

   #       Service side of ASCP protocol.

   #

   # Copyright (c) 1998-2002 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/indiva/lib/ascp-service.tcl,v 1.2 2002/07/11 19:32:55 weitsang Exp $

  
  import ASCP
  import MashTimer
  import MashSoftState
  
  Class ASCP/Service -superclass ASCP
  
  ASCP/Service instproc init { spec bw srv_inst } {
      $self next $spec $bw
      $self set srv_inst_ $srv_inst
  
      $self instvar client_
      $self announce_alive
      new MashTimer/ConstBW 2000 "$self announce_alive" $bw
      set client_ [new MashSoftState/Adaptive 1 16000 "$self exit" 8]
  
      $self set on_exit_callback_ ""
  }
  
  ASCP/Service instproc agent_type {} {
      return "s"
  }
  
  ASCP/Service instproc process_packet { addr packet } {
  
      $self instvar agent_ srv_inst_ client_
  
      # Ignore packets that are not for us.

      if { [$packet service_instance] != $srv_inst_ } {
          #delete $packet

          return
      }
  
      if { [$packet agent_type] == "c" } {
          switch -exact -- [$packet operation] {
              alive {
                  $self announce_alive
                  $client_ refresh
              }
              bye {
                  # client say bye bye.  

                  # We should not exit here, because there may be more than 1 client

                  # using our service.

              }
          }
      } else {
          # Duplicate server announcement.

          if { [string compare [$packet agent_id] [$self agent_id]] < 0 } {
              $self exit
          }
      }
      #delete $packet

  }
  
  
  ASCP/Service instproc announce_alive { } {
      set packet [new ASCPPacket]
      $packet agent_type [$self agent_type]
      $packet agent_id [$self agent_id]
      $packet service_instance [$self service_instance]
      $packet args [$self args]
      $packet operation "alive"
  
      $self announce [$packet to_string]
      delete $packet
  }
  
  
 # 

 # Callback when we failed to receive alive message from a client.

 #

 ASCP/Service instproc on_exit {callback} {
     $self instvar on_exit_callback_
     lappend on_exit_callback_ $callback
 }
 
 
 ASCP/Service instproc exit {} {
     $self bye
     $self instvar on_exit_callback_
     foreach cb $on_exit_callback_ {
         eval $cb
     }
     exit 0
 }
 
 ASCP/Service instproc service_instance {} {
     $self instvar srv_inst_
     return $srv_inst_
 }
 
 ASCP/Service instproc agent_id {} {
     global argv0
     return "[lindex [file split $argv0] end]:[pid]:${self}@[info hostname]:[$self control_port]"
 }
 
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