[cxml-devel] Catalog problems

[David Lichteblau]

Quoting Adam C. Emerson (aemerson at acm.org):
> I've been trying to use the CXML catalog feature, but so far I haven't
> had any success.  Is there something that I am doing that is obviously
> wrong?

No, that catalog file looks fine.  This is obviously an under-tested
feature in CXML...

Three issues:

  1. The catalog spec demands that errors encountered while parsing the
     catalog file are to be ignored, thereby obscuring problem #2.
  2. The catalog format is specified with Schema (for namespace
     support), not actually with a DTD.  Since CXML doesn't have Schema
     support yet, I decided back then to validate against the DTD instead,
     against the advice to the contrary in the spec.  I should have have
     known better -- your file fails DTD validation despite probably
     being correct (due to the extra namespace declarations not allowed
     by the DTD).
  3. And then there's also an obvious bug in <group> handling in CXML...

Can you try the attached patch?  It disables validation (more of a
workaround than a solution, but probably better than nothing for now)
and fixes bug #3.


Thanks,
David
-------------- next part --------------
Index: catalog.lisp
===================================================================
RCS file: /project/cxml/cvsroot/cxml/xml/catalog.lisp,v
retrieving revision 1.1.1.16
diff -u -r1.1.1.16 catalog.lisp
--- catalog.lisp	13 Mar 2005 18:02:56 -0000	1.1.1.16
+++ catalog.lisp	9 Jan 2006 00:03:29 -0000
@@ -222,8 +222,9 @@
 (defun parse-catalog-file (uri)
   (handler-case
       (parse-catalog-file/strict uri)
-    (file-error () nil)
-    (parser-error () nil)))
+    ((or file-error parser-error) (c)
+      (warn "ignoring catalog error: ~A" c)
+      nil)))
 
 (defparameter *catalog-dtd*
     (let* ((cxml
@@ -250,7 +251,7 @@
         (parse-stream s
                       (make-recoder (make-instance 'catalog-parser :uri uri)
                                     #'rod-to-utf8-string)
-                      :validate t
+                      :validate nil
                       :dtd (make-extid nil dtd-sysid)
                       :root #"catalog"
                       :entity-resolver #'entity-resolver)))))
@@ -284,7 +285,11 @@
   (setf lname (or lname qname))
   ;; we can dispatch on lnames only because we validate against the DTD,
   ;; which disallows other namespaces.
-  (push (string-or (get-attribute/lname "prefer" attrs) (prefer handler))
+  (push (let ((new (get-attribute/lname "prefer" attrs)))
+          (cond
+            ((equal new "public") :public)
+            ((equal new "system") :system)
+            ((null new) (prefer handler))))
         (prefer-stack handler))
   (push (string-or (get-attribute/lname "base" attrs) (base handler))
         (base-stack handler))