Fix bug #1098075: Cancelling character table dialog in song importer causes OpenLP to crash

bzr-revno: 2131
Fixes: https://launchpad.net/bugs/1098075

openlp/plugins/songs/lib/__init__.py

@@ -581,6 +581,8 @@ def strip_rtf(text, default_encoding=None):
                     try:
                         encoding, default_encoding = get_encoding(font, 
                             font_table, default_encoding, failed=failed)
+                        if not encoding:
+                            return None
                         out.append(chr(charcode).decode(encoding))
                     except UnicodeDecodeError:
                         failed = True

openlp/plugins/songs/lib/ewimport.py

@@ -180,7 +180,10 @@ class EasyWorshipSongImport(SongImport):
                         self.addAuthor(author_name.strip())
                 if words:
                     # Format the lyrics
-                    words, self.encoding = strip_rtf(words, self.encoding)
+                    result = strip_rtf(words, self.encoding)
+                    if result is None:
+                        return
+                    words, self.encoding = result
                     verse_type = VerseType.Tags[VerseType.Verse]
                     for verse in SLIDE_BREAK_REGEX.split(words):
                         verse = verse.strip()

openlp/plugins/songs/lib/songproimport.py

@@ -109,7 +109,10 @@ class SongProImport(SongImport):
             self.finish()
             return
         if u'rtf1' in text:
-            text, self.encoding = strip_rtf(text, self.encoding)
+            result = strip_rtf(text, self.encoding)
+            if result is None:
+                return
+            text, self.encoding = result
             text = text.rstrip()
         if not text:
             return

openlp/plugins/songs/lib/sundayplusimport.py

@@ -150,7 +150,10 @@ class SundayPlusImport(SongImport):
                             verse_type = HOTKEY_TO_VERSE_TYPE[value]
                     if name == 'rtf':
                         value = self.unescape(value)
-                        verse, self.encoding = strip_rtf(value, self.encoding)
+                        result = strip_rtf(value, self.encoding)
+                        if result is None:
+                            return
+                        verse, self.encoding = result
                         lines = verse.strip().split('\n')
                         # If any line inside any verse contains CCLI or
                         # only Public Domain, we treat this as special data: