[vala/staging] libvaladoc/girimporter: Don't guess length of xml header, iterate forward to <repository>

[Rico Tzschichholz <ricotz src gnome org>]

commit 6bda851954033cd570882517a464f78aff23a2f2
Author: Rico Tzschichholz <ricotz ubuntu com>
Date:   Sat Mar 20 16:19:35 2021 +0100

    libvaladoc/girimporter: Don't guess length of xml header, iterate forward to <repository>
    
    If e.g. the xml header is missing, it resulted in errors like:
    
        error: expected start element of `repository'
        error: unsupported GIR version (null) (supported: 1.2)

 libvaladoc/importer/girdocumentationimporter.vala | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)
---
diff --git a/libvaladoc/importer/girdocumentationimporter.vala 
b/libvaladoc/importer/girdocumentationimporter.vala
index b7d475043..e0ae01d6c 100644
--- a/libvaladoc/importer/girdocumentationimporter.vala
+++ b/libvaladoc/importer/girdocumentationimporter.vala
@@ -69,10 +69,14 @@ public class Valadoc.Importer.GirDocumentationImporter : DocumentationImporter {
                this.reader = new Vala.MarkupReader (source_file);
 
                // xml prolog
-               next ();
-               next ();
+               do {
+                       next ();
+                       if (current_token == Vala.MarkupTokenType.EOF) {
+                               error ("unexpected end of file");
+                               return;
+                       }
+               } while (current_token != Vala.MarkupTokenType.START_ELEMENT && reader.name != "repository");
 
-               next ();
                parse_repository ();
 
                reader = null;