Note that some of the IRIX problems might no longer exist - and get rid

of the libpcap patch, as it's incorporated into current versions of
libpcap.


git-svn-id: http://anonsvn.wireshark.org/wireshark/trunk@11758 f5534014-38df-0310-8fa8-9805f1628bb7

README.irix

@@ -1,7 +1,7 @@
 $Id$
 
 1. Some problems seen by one person who tried to build Ethereal on IRIX;
-your mileage may vary.
+your mileage may vary.  Some comments hae been added.
 
 To: ethereal-dev@zing.org
 Subject: Re: [ethereal-dev] Ethereal on SGI
@@ -36,6 +36,11 @@ PROBLEM #1
    BETTER SOLUTION:  Modify configure to support RPATH for more platforms
                      than Solaris.
 
+[NOTE: configure is generated from configure.in and acinclude.m4, and
+all the linking stuff is done by libtool.  We don't recommend the
+LD_LIBRARY_PATH hack - perhaps we did so in the past, but we don't do so
+now.]
+
 ==========
 PROBLEM #2
 ==========
@@ -57,6 +62,10 @@ PROBLEM #2
 
 Randall
 
+[NOTE: we don't use the __P macro ourselves; some of the SNMP libraries
+might, but that's a bug in the libraries if they require you to define
+__P in order to use them.]
+
 ===============================================================================
 
 Problem #1:
@@ -115,127 +124,11 @@ Problem #3 (same as Problem #1):
 
 2. Patches to libpcap that may be necessary
 
-On IRIX, the libpcap library uses, in "pcap_open_live()", the snapshot
-length passed in, without reducing it to be less than or equal to the
-MTU of the interface.  If the snapshot length is larger than the
-interface MTU, IRIX will return an error; this means that, for example,
-the Ethereal default snapshot length of 65535, chosen so that all of the
-packet is captured, will not work.
-
-Here is a patch to libpcap 0.4 source that should fix that problem.  If
-it doesn't fix the problem, or if it reduces the snapshot length below
-the MTU (so that a snapshot length of 65535 doesn't capture all the data
-in the packets), please report this to ethereal-dev@ethereal.com, so
-that we know that it didn't work - we'll probably send you debugging
-patches in the hopes of being able to make it work.
-
-diff -c ../libpcap-0.4/pcap-snoop.c ./pcap-snoop.c
-*** ../libpcap-0.4/pcap-snoop.c	Tue Apr  8 21:07:01 1997
---- ./pcap-snoop.c	Tue Jan 18 00:16:18 2000
-***************
-*** 126,132 ****
---- 126,135 ----
-  	struct sockaddr_raw sr;
-  	struct snoopfilter sf;
-  	u_int v;
-+ 	int ll_hdrlen;
-+ 	int snooplen;
-  	pcap_t *p;
-+ 	struct ifreq ifr;
-  
-  	p = (pcap_t *)malloc(sizeof(*p));
-  	if (p == NULL) {
-***************
-*** 154,169 ****
-  	}
-  	v = 64 * 1024;
-  	(void)setsockopt(fd, SOL_SOCKET, SO_RCVBUF, (char *)&v, sizeof(v));
-- 	if (ioctl(fd, SIOCSNOOPLEN, &snaplen) < 0) {
-- 		sprintf(ebuf, "SIOCSNOOPLEN: %s", pcap_strerror(errno));
-- 		goto bad;
-- 	}
-- 	p->snapshot = snaplen;
-- 	v = 1;
-- 	if (ioctl(fd, SIOCSNOOPING, &v) < 0) {
-- 		sprintf(ebuf, "SIOCSNOOPING: %s", pcap_strerror(errno));
-- 		goto bad;
-- 	}
-  	/*
-  	 * XXX hack - map device name to link layer type
-  	 */
---- 157,162 ----
-***************
-*** 179,195 ****
---- 172,242 ----
-  	    strncmp("qaa", device, 3) == 0) {
-  		p->linktype = DLT_EN10MB;
-  		p->offset = RAW_HDRPAD(sizeof(struct ether_header));
-+ 		ll_hdrlen = sizeof(struct ether_header);
-  	} else if (strncmp("ipg", device, 3) == 0 ||
-  		   strncmp("rns", device, 3) == 0 ||	/* O2/200/2000 FDDI */
-  		   strncmp("xpi", device, 3) == 0) {
-  		p->linktype = DLT_FDDI;
-  		p->offset = 3;				/* XXX yeah? */
-+ 		ll_hdrlen = 13;
-  	} else if (strncmp("ppp", device, 3) == 0) {
-  		p->linktype = DLT_RAW;
-+ 		ll_hdrlen = 0;	/* DLT_RAW meaning "no PPP header, just the IP packet"? */
-  	} else if (strncmp("lo", device, 2) == 0) {
-  		p->linktype = DLT_NULL;
-+ 		ll_hdrlen = 4;	/* is this just like BSD's loopback device? */
-  	} else {
-  		sprintf(ebuf, "snoop: unknown physical layer type");
-+ 		goto bad;
-+ 	}
-+ #ifdef SIOCGIFMTU
-+ 	/*
-+ 	 * XXX - IRIX appears to give you an error if you try to set the
-+ 	 * capture length to be greater than the MTU, so let's try to get
-+ 	 * the MTU first and, if that succeeds, trim the snap length
-+ 	 * to be no greater than the MTU.
-+ 	 */
-+ 	(void)strncpy(ifr.ifr_name, device, sizeof(ifr.ifr_name));
-+ 	if (ioctl(fd, SIOCGIFMTU, (char *)&ifr) < 0) {
-+ 		sprintf(ebuf, "SIOCGIFMTU: %s", pcap_strerror(errno));
-+ 		goto bad;
-+ 	}
-+ 	/*
-+ 	 * OK, we got it.
-+ 	 * XXX - some versions of IRIX 6.5 define "ifr_mtu" and have an
-+ 	 * "ifru_metric" member of the "ifr_ifru" union in an "ifreq"
-+ 	 * structure, others don't.
-+ 	 *
-+ 	 * I've no idea what's going on, so, if "ifr_mtu" isn't defined,
-+ 	 * we define it as "ifr_metric", as using that field appears to
-+ 	 * work on the versions that lack "ifr_mtu" (and, on those that
-+ 	 * don't lack it, "ifru_metric" and "ifru_mtu" are both "int"
-+ 	 * members of the "ifr_ifru" union, which suggests that they
-+ 	 * may be interchangeable in this case).
-+ 	 */
-+ #ifndef ifr_mtu
-+ #define ifr_mtu	ifr_metric
-+ #endif
-+ 	if (snaplen > ifr.ifr_mtu)
-+ 		snaplen = ifr.ifr_mtu;
-+ #endif
-+ 
-+ 	/*
-+ 	 * The argument to SIOCSNOOPLEN is the number of link-layer
-+ 	 * payload bytes to capture - it doesn't count link-layer
-+ 	 * header bytes.
-+ 	 */
-+ 	snooplen = snaplen - ll_hdrlen;
-+ 	if (snooplen < 0)
-+ 		snooplen = 0;
-+ 	if (ioctl(fd, SIOCSNOOPLEN, &snooplen) < 0) {
-+ 		sprintf(ebuf, "SIOCSNOOPLEN: %s", pcap_strerror(errno));
-+ 		goto bad;
-+ 	}
-+ 	p->snapshot = snaplen;
-+ 	v = 1;
-+ 	if (ioctl(fd, SIOCSNOOPING, &v) < 0) {
-+ 		sprintf(ebuf, "SIOCSNOOPING: %s", pcap_strerror(errno));
-  		goto bad;
-  	}
-  
+On IRIX, older versions of the libpcap library use, in
+"pcap_open_live()", the snapshot length passed in, without reducing it
+to be less than or equal to the MTU of the interface.  If the snapshot
+length is larger than the interface MTU, IRIX will return an error; this
+means that, for example, the Ethereal default snapshot length of 65535,
+chosen so that all of the packet is captured, will not work.
 
+Current versions of libpcap, from tcpdump.org, do not do so.