00001 /* -*- Mode:C++; c-basic-offset:8; tab-width:8; indent-tabs-mode:t -*- */ 00002 /* 00003 * Copyright (c) 1997 Regents of the University of California. 00004 * All rights reserved. 00005 * 00006 * Redistribution and use in source and binary forms, with or without 00007 * modification, are permitted provided that the following conditions 00008 * are met: 00009 * 1. Redistributions of source code must retain the above copyright 00010 * notice, this list of conditions and the following disclaimer. 00011 * 2. Redistributions in binary form must reproduce the above copyright 00012 * notice, this list of conditions and the following disclaimer in the 00013 * documentation and/or other materials provided with the distribution. 00014 * 3. All advertising materials mentioning features or use of this software 00015 * must display the following acknowledgement: 00016 * This product includes software developed by the MASH Research 00017 * Group at the University of California Berkeley. 00018 * 4. Neither the name of the University nor of the Research Group may be 00019 * used to endorse or promote products derived from this software without 00020 * specific prior written permission. 00021 * 00022 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 00023 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 00024 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 00025 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 00026 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 00027 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 00028 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 00029 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 00030 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 00031 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 00032 * SUCH DAMAGE. 00033 * 00034 * @(#) $Header: /cvsroot/nsnam/ns-2/common/flags.h,v 1.19 2004/10/28 01:20:10 sfloyd Exp $ 00035 */ 00036 00037 /* 00038 * contains a "flags header", which is common to each packet 00039 */ 00040 00041 #ifndef ns_flags_h 00042 #define ns_flags_h 00043 00044 #include "config.h" 00045 #include "packet.h" 00046 00047 struct hdr_flags { 00048 unsigned char ecn_; /* transport receiver notifying 00049 * transport sender of ECN 00050 * (ECN Echo bit in TCP header) */ 00051 unsigned char ecn_to_echo_; /* ecn to be echoed back in the * 00052 * opposite direction * 00053 * (CE bit in IP header) */ 00054 unsigned char eln_; /* explicit loss notification (snoop) */ 00055 unsigned char fs_; /* tcp fast start (work in progress --venkat) */ 00056 unsigned char no_ts_; /* don't use the tstamp of this pkt for rtt */ 00057 unsigned char pri_; /* unused */ 00058 unsigned char ecn_capable_; /* an ecn-capable tranport * 00059 * (ECT bit in IP header) */ 00060 unsigned char cong_action_; /* Congestion Action. Transport 00061 * sender notifying transport 00062 * receiver of responses to congestion. 00063 * (CWR bit in TCP header) */ 00064 unsigned char qs_; /* Packet is from Quick-Start window, i.e. 00065 * a window following an approved QS request. 00066 */ 00067 /* 00068 * these functions use the newer ECN names but leaves the actual field 00069 * names above to maintain backward compat 00070 */ 00071 unsigned char& ect() { return ecn_capable_; } 00072 /* (ECT bit in IP header) */ 00073 unsigned char& ecnecho() { return ecn_; } 00074 /* (ECN Echo bit in TCP header) */ 00075 unsigned char& ce() { return ecn_to_echo_; } 00076 /* (CE bit in IP header) */ 00077 unsigned char& cong_action() { return cong_action_; } 00078 /* (CWR bit in TCP header-old name) */ 00079 unsigned char& cwr() { return cong_action_; } 00080 /* (CWR bit in TCP header) */ 00081 00082 unsigned char& qs() { return qs_; } /* Quick-Start packet */ 00083 00084 static int offset_; 00085 inline static int& offset() { return offset_; } 00086 inline static hdr_flags* access(const Packet* p) { 00087 return (hdr_flags*) p->access(offset_); 00088 } 00089 }; 00090 00091 #endif