Changeset 7124

Timestamp:

01/30/10 07:13:54 (7 months ago)

Author:

dbaelde

Message:

Fix two bugs in content layer management, one of which easily causes crashes when converting mono to stereo. The goal there is to never have two consecutive layers of the same type, and to avoid empty layers.

Files:

• trunk/liquidsoap/src/stream/frame.ml (modified) (2 diffs)

trunk/liquidsoap/src/stream/frame.ml

@@ -393 +393 @@
   * invalidation of all data after the given position. *)
 let content_of_type frame pos content_type =
-  let rec aux acc = function
+  (* Start_pos indicates the start of the first layer,
+   * acc contains the previous layers in reverse order,
+   * and we're walking through the next layers. *)
+  let rec aux start_pos acc = function
     | [] -> assert false
     | (end_pos,content)::l ->
-        if end_pos<=pos then aux ((end_pos,content)::acc) l else
+        if end_pos<=pos then aux end_pos ((end_pos,content)::acc) l else
+          (* We are starting somewhere inside that layer. *)
           if content_has_type content content_type then begin
             if l=[] then assert (end_pos = !!size) else
@@ -402 +406 @@
             content
           end else begin
-            let acc =
-              if pos=0 then acc else (pos,content)::acc
-            in
-            let content = create_content content_type in
-              frame.contents <- List.rev ((!!size, content)::acc) ;
-              content
+            if pos=start_pos then
+              (* We are erasing the current layer. *)
+              match acc with
+                | (end_pos,content)::acc
+                  when content_has_type content content_type ->
+                    (* We must re-use the previous layer. *)
+                    frame.contents <- List.rev ((!!size, content)::acc) ;
+                    content
+                | _ ->
+                    let content = create_content content_type in
+                      frame.contents <- List.rev ((!!size, content)::acc) ;
+                      content
+            else
+              let acc = (pos,content)::acc in
+              let content = create_content content_type in
+                frame.contents <- List.rev ((!!size, content)::acc) ;
+                content
           end
   in
-    aux [] frame.contents
+    aux 0 [] frame.contents
 
 let blit_content src src_pos dst dst_pos len =