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Wireshark-dev: [Wireshark-dev] Recent changes in composite TVB (extra changes beside move)

From: Jakub Zawadzki <darkjames-ws@xxxxxxxxxxxx>
Date: Wed, 31 Jul 2013 23:42:03 +0200
Hi,

I should've first commit this changes and later move composite stuff to another file, but I haven't thought.
Sorry. Anyway, attaching diff with important changes.

If anyone has some time to do review it'd be great.

Thanks,
Kuba.

--- 9d519b5659aa8c0c4aa984bc6169909eb31be7d6_2.c	2013-07-31 22:50:46.144101741 +0200
+++ 9d519b5659aa8c0c4aa984bc6169909eb31be7d6_1.c	2013-07-31 22:50:36.800818660 +0200
@@ -32,11 +32,10 @@
 	guint	    i, num_members;
 	tvb_comp_t *composite;
 	tvbuff_t   *member_tvb = NULL;
-	guint	    member_offset, member_length;
+	guint	    member_offset;
 	GSList	   *slist;
-	int         exception;
 
-	DISSECTOR_ASSERT(tvb->ops == get_tvb_composite_ops());
+	/* DISSECTOR_ASSERT(tvb->ops == &tvb_composite_ops); */
 
 	/* Maybe the range specified by offset/length
 	 * is contiguous inside one of the member tvbuffs */
@@ -52,16 +51,14 @@
 	}
 	DISSECTOR_ASSERT(member_tvb);
 
-	exception = check_offset_length_no_exception(member_tvb,
-					     abs_offset - composite->start_offsets[i],
-					     abs_length, &member_offset, &member_length);
+	member_offset = abs_offset - composite->start_offsets[i];
 
-	if (!exception) {
+	if (tvb_bytes_exist(member_tvb, member_offset, abs_length)) {
 		/*
 		 * The range is, in fact, contiguous within member_tvb.
 		 */
 		DISSECTOR_ASSERT(!tvb->real_data);
-		return ensure_contiguous_no_exception(member_tvb, member_offset, member_length, NULL);
+		return tvb_get_ptr(member_tvb, member_offset, abs_length);
 	}
 	else {
 		tvb->real_data = (guint8 *)tvb_memdup(tvb, 0, -1);
@@ -72,7 +69,7 @@
 }
 
 static void *
-composite_memcpy(tvbuff_t *tvb, void* _target, guint abs_offset, size_t abs_length)
+composite_memcpy(tvbuff_t *tvb, void* _target, guint abs_offset, guint abs_length)
 {
 	struct tvb_composite *composite_tvb = (struct tvb_composite *) tvb;
 	guint8 *target = (guint8 *) _target;
@@ -81,10 +78,9 @@
 	tvb_comp_t *composite;
 	tvbuff_t   *member_tvb = NULL;
 	guint	    member_offset, member_length;
-	int         exception;
 	GSList	   *slist;
 
-	DISSECTOR_ASSERT(tvb->ops == get_tvb_composite_ops());
+	/* DISSECTOR_ASSERT(tvb->ops == &tvb_composite_ops); */
 
 	/* Maybe the range specified by offset/length
 	 * is contiguous inside one of the member tvbuffs */
@@ -100,12 +96,11 @@
 	}
 	DISSECTOR_ASSERT(member_tvb);
 
-	exception = check_offset_length_no_exception(member_tvb, abs_offset - composite->start_offsets[i],
-				(gint) abs_length, &member_offset, &member_length);
+	member_offset = abs_offset - composite->start_offsets[i];
 				
-	if (!exception) {
+	if (tvb_bytes_exist(member_tvb, member_offset, abs_length)) {
 		DISSECTOR_ASSERT(!tvb->real_data);
-		return tvb_memcpy(member_tvb, target, member_offset, member_length);
+		return tvb_memcpy(member_tvb, target, member_offset, abs_length);
 	}
 	else {
 		/* The requested data is non-contiguous inside
@@ -113,12 +108,10 @@
 		 * then iterate across the other member tvb's, copying their portions
 		 * until we have copied all data.
 		 */
-		exception = compute_offset_and_remaining(member_tvb, abs_offset - composite->start_offsets[i],
-				&member_offset, &member_length);
-		DISSECTOR_ASSERT(!exception);
+		member_length = tvb_length_remaining(member_tvb, member_offset);
 
 		/* composite_memcpy() can't handle a member_length of zero.  */
-		DISSECTOR_ASSERT(member_length);
+		DISSECTOR_ASSERT(member_length > 0);
 
 		tvb_memcpy(member_tvb, target, member_offset, member_length);
 		abs_offset	+= member_length;