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, 6 deletions

diff --git a/packet-smb-logon.c b/packet-smb-logon.c
index a26b68a5b5..a927de74f7 100644
--- a/packet-smb-logon.c
+++ b/packet-smb-logon.c
@@ -2,7 +2,7 @@
  * Routines for SMB net logon packet dissection
  * Copyright 2000, Jeffrey C. Foster <jfoste@woodward.com>
  *
- * $Id: packet-smb-logon.c,v 1.33 2003/05/21 10:16:10 sahlberg Exp $
+ * $Id: packet-smb-logon.c,v 1.34 2003/06/12 08:33:30 guy Exp $
  *
  * Ethereal - Network traffic analyzer
  * By Gerald Combs <gerald@ethereal.com>
@@ -310,18 +310,17 @@ dissect_smb_logon_LM20_resp(tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *t
 static int
 dissect_smb_pdc_query(tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree, int offset)
 {
-	char *name = NULL;
+	char *name;
 
 	/*** 0x07 Query for Primary PDC  ***/
 
 	/* computer name */
 	offset = display_ms_string(tvb, tree, offset, hf_computer_name, &name);
 
-	if (name && check_col(pinfo->cinfo, COL_INFO)) {
+	if (check_col(pinfo->cinfo, COL_INFO))
 		col_append_fstr(pinfo->cinfo, COL_INFO, " from %s", name);
-		g_free(name);
-		name = NULL;
-	}
+
+	g_free(name);
 
 	/* mailslot name */
 	offset = display_ms_string(tvb, tree, offset, hf_mailslot_name, NULL);