small fix to openid message find_ns method

it foolishly failed in presence of ns field and absence of namespace in
question.

Signed-off-by: Michael Krelin <hacker@klever.net>

1 files changed, 3 insertions, 1 deletions

diff --git a/lib/openid_message.cc b/lib/openid_message.cc
index 588bd62..75e59b3 100644
--- a/lib/openid_message.cc
+++ b/lib/openid_message.cc
@@ -204,28 +204,30 @@ namespace opkele {
                                 fields,fnc,fields.size()-fnc);
                     else
                         signeds.append(fields,fnc,fields.size()-fnc);
                 }
             }
         }catch(failed_lookup&) {
             signeds.assign(fields,fnc,fields.size()-fnc);
         }
         set_field("signed",signeds);
     }
 
     string basic_openid_message::find_ns(const string& uri,const char *pfx) const {
-        if(has_field("ns"))
+        try {
             return get_ns(uri);
+        }catch(failed_lookup&) {
         return pfx;
     }
+    }
     string basic_openid_message::allocate_ns(const string& uri,const char *pfx) {
         if(!has_field("ns"))
             return pfx;
         if(has_ns(uri))
             throw bad_input(OPKELE_CP_ "OpenID message already contains namespace");
         string rv = pfx;
         if(has_field("ns."+rv)) {
             string::reference c=rv[rv.length()];
             for(c='a';c<='z' && has_field("ns."+rv);++c);
             if(c=='z')
                 throw exception(OPKELE_CP_ "Failed to allocate namespace");
         }