Add new routines:

	tvb_get_string() - takes a tvbuff, an offset, and a length as
	arguments, allocates a buffer big enough to hold a string with
	the specified number of bytes plus an added null terminator
	(i.e., length+1), copies the specified number of bytes from the
	tvbuff, at the specified offset, to that buffer and puts in a
	null terminator, and returns a pointer to that buffer (or throws
	an exception before allocating the buffer if that many bytes
	aren't available in the tvbuff);

	tvb_get_stringz() - takes a tvbuff, an offset, and a pointer to
	a "gint" as arguments, gets the size of the null-terminated
	string starting at the specified offset in the tvbuff (throwing
	an exception if the null terminator isn't found), allocates a
	buffer big enough to hold that string, copies the string to that
	buffer, and returns a pointer to that buffer and stores the
	length of the string (including the terminating null) in the
	variable pointed to by the "gint" pointer.

Replace many pieces of code allocating a buffer and copying a string
with calls to "tvb_get_string()" (for one thing, "tvb_get_string()"
doesn't require you to remember that the argument to
"tvb_get_nstringz0()" is the size of the buffer into which you're
copying the string, which might be the length of the string to be copied
*plus 1*).

Don't use fixed-length buffers for null-terminated strings (even if the
code that generates those packets has a #define to limit the length of
the string).  Use "tvb_get_stringz()", instead.

In some cases where a value is fetched but is only used to pass an
argument to a "proto_tree_add_XXX" routine, use "proto_tree_add_item()"
instead.

svn path=/trunk/; revision=7859

1 files changed, 5 insertions, 8 deletions

diff --git a/packet-sdp.c b/packet-sdp.c
index 71cf27569e..301785b03c 100644
--- a/packet-sdp.c
+++ b/packet-sdp.c
@@ -4,7 +4,7 @@
  * Jason Lango <jal@netapp.com>
  * Liberally copied from packet-http.c, by Guy Harris <guy@alum.mit.edu>
  *
- * $Id: packet-sdp.c,v 1.33 2002/08/28 21:00:30 jmayer Exp $
+ * $Id: packet-sdp.c,v 1.34 2003/06/12 08:33:29 guy Exp $
  *
  * Ethereal - Network traffic analyzer
  * By Gerald Combs <gerald@ethereal.com>
@@ -272,20 +272,17 @@ dissect_sdp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 			break;
 		}
 		tokenoffset = 2;
-		if( hf == hf_unknown )
-		  tokenoffset = 0;
-		string = g_malloc(linelen - tokenoffset + 1);
-		CLEANUP_PUSH(g_free, string);
-		tvb_memcpy(tvb, (guint8 *)string, offset + tokenoffset,
+		if (hf == hf_unknown)
+			tokenoffset = 0;
+		string = tvb_get_string(tvb, offset + tokenoffset,
 		    linelen - tokenoffset);
-		string[linelen - tokenoffset] = '\0';
 		sub_ti = proto_tree_add_string_format(sdp_tree,hf,tvb, offset,
 					       linelen, string,
 					       "%s: %s",
 					       proto_registrar_get_name(hf),
 					       format_text(string,
 					         linelen - tokenoffset));
-		CLEANUP_CALL_AND_POP;
+		g_free(string);
 		call_sdp_subdissector(tvb_new_subset(tvb,offset+tokenoffset,
 						     linelen-tokenoffset,-1),
 				      hf,sub_ti);