Re: [xml] Error with xmlSchemaParse

[Kasimier Buchcik <kbuchcik 4commerce de>]

HI,

Jyothirmayee, P wrote:
> Hi,
>
> When trying to parse an xml schema file using "xmlSchemaParse" function, 
> following errors are
> displayed "Unable to load an external entity....." for both the urls 
> given below :
>
> "http://www.w3.org/TR/2002/REC-xmldsig-core-20020212/xmldsig-core-schema.xsd"; 
>
>
> and
>
> "http://www.w3.org/TR/2002/REC-xmlenc-core-20021210/xenc-schema.xsd";
[...]
> Please help me in finding out the problem. I am using the 
> libxml2(2.6.13.win32) version.

I tried with Libxml2 2.6.17 and it retrieves the schemata:

testSchemas test-import.xsd
http://www.w3.org/TR/2002/REC-xmlenc-core-20021210/xenc-schema.xsd:123: 
element attribute: Schemas parser error : Element 'attribute': A global 
attribute declaration with the name 'URI' does already exist.

xmllint --version
xmllint: using libxml version 20617CVS2322
   compiled with: DTDValid FTP HTTP HTML C14N Catalog XPath XPointer 
XInclude Iconv Unicode Regexps Automata Schemas Modules

But there's an other bug.
We currently use a combination of "name", "namespace" and the parent
element's "name" to compute a unique value for an attribute declaration
to be put in a hash table.
With the help of your report this is asserted to be ambigious in the
following scenario:
1. multiple top-level complex types have different target namespaces
   but have the _same_ _name_; this can happen if schemata are
   imported
2. those complex types contain attributes with an equal name
3. those attributes are in no namespace

So here we have:

imported XML Schema:
http://www.w3.org/TR/2002/REC-xmldsig-core-20020212/xmldsig-core-schema.xsd

- complex type "ReferenceType",
    - target namespace "http://www.w3.org/2000/09/xmldsig#";
    - attribute "URI"
      - no target namespace

--> unique attribute key: "URI", NULL, "ReferenceType"

imported XML Schema:
http://www.w3.org/TR/2002/REC-xmlenc-core-20021210/xenc-schema.xsd

- complex type "ReferenceType",
    - target namespace "http://www.w3.org/2001/04/xmlenc#";
    - attribute "URI"
      - no target namespace

--> unique attribute key: "URI", NULL, "ReferenceType"

A nice case. Both keys are equal. I'll try to fix this soon.

Regards,

Kasimier