segmentation fault

Hi David, Federico,

I have been debugging a segmentation fault that only happened on
one machine. After a lot of debugging I found the cause. The
backtrace I get is:

#7  0x41161903 in strlen () from /lib/tls/libc.so.6
#8  0x401b59eb in ost::RTPApplication::findCNAME (this=0x0)
     at char_traits.h:143
#9  0x401b5c49 in RTPApplication (this=0x401c9d80, cname=@0xbfffe2a0)
     at source.cpp:161
#10 0x401b5d16 in ost::defaultApplication () at stl_alloc.h:652
#11 0x081ad0dc in t_twinkle_rtp_session (this=0x84bb668, host=@0x0,
     port=5004) at twinkle_rtp_session.cpp:6
#12 0x081a0b1f in t_audio_session (this=0x83acd10, _session=0x84ae35c,
     _recv_host=@0x82290e8, _recv_port=5004, _dst_host=@0x845d018,
     _dst_port=12668, _codec=139125596, _ptime=20) at basic_string.h:716

I found that this crash can happen for 2 reasons:

1) LOGNAME is not set
2) The hostname is not in /etc/hosts

In both cases ccrtp tries to use a NULL pointer.

Attached you find a patch that fixes the problem. I hope you will fix
this in the next release.

Best regards,
Michel

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--- ccrtp-1.3.5/src/source.cpp	2005-01-24 16:14:55.000000000 +0100
+++ ccrtp-1.3.5-patched/src/source.cpp	2005-11-26 18:05:11.000000000 +0100
@@ -76,7 +76,7 @@
 	//    customization of the environment.
 	// Try both LOGNAME and USER env. var.
 	const char *user = Process::getEnv("LOGNAME");
-	if ( !strcmp(user,"") )
+	if ( !user || !strcmp(user,"") )
 		user = Process::getEnv("USER");
 	if ( user )
 		username = user;
@@ -231,9 +231,18 @@
 	// build string username@host_fqn
 	std::string username;
 	findusername(username);
-	
+	 
+	// First create an InetHostAddress object, otherwise the
+	// object will be destructed and the hostname corrupted.
+	InetHostAddress iha;
+	const char *p = iha.getHostname();
+
+	// Returned hostname can be NULL
+	std::string hname;
+	if (p) hname = p;
+
 	setSDESItem(SDESItemTypeCNAME, 
-		    username + "@" + InetHostAddress().getHostname());
+		    username + "@" + hname);
 }
 
 #ifdef	CCXX_NAMESPACES