[Devel] FT_LruList_Remove_Selection doesn't update list->num_nodes

[Alexander Malmberg]

Hi

In 2.1.4, FT_LruList_Remove_Selection doesn't update list->num_nodes
when it removes nodes. In some cases, this causes the cache system to
start returning spurious out of memory errors. I have no simple test
that shows the errors, but this assertion at the end of the function:

    {
      FT_LruNode node;
      int num=0;
      for (node=list->nodes;node;node=node->next)
        num++;
      FT_ASSERT(num==list->num_nodes);
    }

will trigger if you run ftview with three fonts and switch back and
forth between them. I've attached a patch that fixes this and corrects a
related assertion in FT_LruList_Lookup.

While debugging this, I found ftccache.c:759, the "if (... || free_count
> manager->num_nodes)", somewhat questionable. Even if it isn't possible to 
> free as many nodes as we want to, it seems more sensible to free as many as 
> possible and try again before failing (or I am reading the code wrong?).

- Alexander Malmberg (not on the list, please cc replies)

Index: ftlru.c
===================================================================
RCS file: /cvs/freetype/freetype2/src/cache/ftlru.c,v
retrieving revision 1.27
diff -u -r1.27 ftlru.c
--- ftlru.c     2003/03/20 07:04:40     1.27
+++ ftlru.c     2003/06/07 19:01:36
@@ -231,7 +231,7 @@
   
           if ( node == NULL )
           {
-            FT_ASSERT( list->nodes == 0 );
+            FT_ASSERT( list->num_nodes == 0 );
             error = FT_Err_Out_Of_Memory;
             goto Exit;
           }
@@ -384,6 +384,7 @@
           clazz->node_done( node, list );
 
         FT_FREE( node );
+       list->num_nodes--;
       }
       else
         pnode = &(*pnode)->next;