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, 4 insertions, 7 deletions

diff --git a/packet-dcerpc.c b/packet-dcerpc.c
index 4c9f172b23..3b171bcb80 100644
--- a/packet-dcerpc.c
+++ b/packet-dcerpc.c
@@ -2,7 +2,7 @@
  * Routines for DCERPC packet disassembly
  * Copyright 2001, Todd Sabin <tas@webspan.net>
  *
- * $Id: packet-dcerpc.c,v 1.128 2003/06/10 05:53:32 guy Exp $
+ * $Id: packet-dcerpc.c,v 1.129 2003/06/12 08:33:29 guy Exp $
  *
  * Ethereal - Network traffic analyzer
  * By Gerald Combs <gerald@ethereal.com>
@@ -1057,17 +1057,14 @@ dissect_ndr_cvstring(tvbuff_t *tvb, int offset, packet_info *pinfo,
         }
     } else {
         /*
-         * First, make sure the entire string is in the tvbuff, and throw
-         * an exception if it isn't.  If the length is bogus, this should
+         * "tvb_get_string()" throws an exception if the entire string
+         * isn't in the tvbuff.  If the length is bogus, this should
          * keep us from trying to allocate an immensely large buffer.
          * (It won't help if the length is *valid* but immensely large,
          * but that's another matter; in any case, that would happen only
          * if we had an immensely large tvbuff....)
          */
-        tvb_ensure_bytes_exist(tvb, offset, buffer_len);
-        s = g_malloc(buffer_len + 1);
-        tvb_memcpy(tvb, s, offset, buffer_len);
-        s[buffer_len] = '\0';
+        s = tvb_get_string(tvb, offset, buffer_len);
         if (tree && buffer_len)
             proto_tree_add_item(string_tree, hfindex, tvb, offset,
                                 buffer_len, drep[0] & 0x10);