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/*
* Copyright (c) Xerox Corporation 1998. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
* Linking this file statically or dynamically with other modules is making
* a combined work based on this file. Thus, the terms and conditions of
* the GNU General Public License cover the whole combination.
*
* In addition, as a special exception, the copyright holders of this file
* give you permission to combine this file with free software programs or
* libraries that are released under the GNU LGPL and with code included in
* the standard release of ns-2 under the Apache 2.0 license or under
* otherwise-compatible licenses with advertising requirements (or modified
* versions of such code, with unchanged license). You may copy and
* distribute such a system following the terms of the GNU GPL for this
* file and the licenses of the other code concerned, provided that you
* include the source code of that other code when and as the GNU GPL
* requires distribution of source code.
*
* Note that people who make modified versions of this file are not
* obligated to grant this special exception for their modified versions;
* it is their choice whether to do so. The GNU General Public License
* gives permission to release a modified version without this exception;
* this exception also makes it possible to release a modified version
* which carries forward this exception.
*
* $Header: /cvsroot/nsnam/ns-2/webcache/inval-agent.cc,v 1.14 2005/08/26 05:05:31 tomh Exp $
*/
//
// Agents used to send and receive invalidation records
//
#include "inval-agent.h"
#include "ip.h"
#include "http.h"
// Implementation 1: Invalidation via multicast heartbeat
int hdr_inval::offset_;
static class HttpInvalHeaderClass : public PacketHeaderClass {
public:
HttpInvalHeaderClass() : PacketHeaderClass("PacketHeader/HttpInval",
sizeof(hdr_inval)) {
bind_offset(&hdr_inval::offset_);
}
} class_httpinvalhdr;
static class HttpInvalClass : public TclClass {
public:
HttpInvalClass() : TclClass("Agent/HttpInval") {}
TclObject* create(int, const char*const*) {
return (new HttpInvalAgent());
}
} class_httpinval_agent;
HttpInvalAgent::HttpInvalAgent() : Agent(PT_INVAL)
{
// It should be initialized to the same as tcpip_base_hdr_size_
bind("inval_hdr_size_", &inval_hdr_size_);
}
void HttpInvalAgent::recv(Packet *pkt, Handler*)
{
hdr_ip *ip = hdr_ip::access(pkt);
if ((ip->saddr() == addr()) && (ip->sport() == port()))
// XXX Why do we need this?
return;
if (app_ == 0)
return;
hdr_inval *ih = hdr_inval::access(pkt);
((HttpApp*)app_)->process_data(ih->size(), pkt->userdata());
Packet::free(pkt);
}
// Send a list of invalidation records in user data area
// realsize: the claimed size
// datasize: the actual size of user data, used to allocate packet
void HttpInvalAgent::send(int realsize, AppData* data)
{
Packet *pkt = allocpkt(data->size());
hdr_inval *ih = hdr_inval::access(pkt);
ih->size() = data->size();
pkt->setdata(data);
// Set packet size proportional to the number of invalidations
hdr_cmn *ch = hdr_cmn::access(pkt);
ch->size() = inval_hdr_size_ + realsize;
Agent::send(pkt, 0);
}
// Implementation 2: Invalidation via TCP.
static class HttpUInvalClass : public TclClass {
public:
HttpUInvalClass() : TclClass("Application/TcpApp/HttpInval") {}
TclObject* create(int argc, const char*const* argv) {
if (argc != 5)
return NULL;
Agent *a = (Agent *)TclObject::lookup(argv[4]);
a->set_pkttype(PT_INVAL); // It's TCP but used for invalidation
if (a == NULL)
return NULL;
return (new HttpUInvalAgent(a));
}
} class_httpuinval_agent;
void HttpUInvalAgent::process_data(int size, AppData* data)
{
target_->process_data(size, data);
}
int HttpUInvalAgent::command(int argc, const char*const* argv)
{
if (strcmp(argv[1], "set-app") == 0) {
// Compatibility interface
HttpApp* c =
(HttpApp*)TclObject::lookup(argv[2]);
target_ = (Process *)c;
return TCL_OK;
}
return TcpApp::command(argc, argv);
}
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