[grilo-plugins] local-metadata: Fixes to video_sanitise_string non-alnum handling

[Bastien Nocera <hadess src gnome org>]

commit a8f3ef6354a31981d98821dbd3b8f20bff19863e
Author: Jan Alexander Steffens (heftig) <jan steffens gmail com>
Date:   Tue May 19 20:53:28 2015 +0200

    local-metadata: Fixes to video_sanitise_string non-alnum handling
    
    - Extract loop condition into a helper function
    - Use g_utf8_get_char to properly convert to unichar
    - Be more defensive about g_utf8_find_prev_char returning NULL
    
    https://bugzilla.gnome.org/show_bug.cgi?id=748604

 src/local-metadata/grl-local-metadata.c |   39 ++++++++++++++++++++++--------
 1 files changed, 28 insertions(+), 11 deletions(-)
---
diff --git a/src/local-metadata/grl-local-metadata.c b/src/local-metadata/grl-local-metadata.c
index 45856be..c7f731e 100644
--- a/src/local-metadata/grl-local-metadata.c
+++ b/src/local-metadata/grl-local-metadata.c
@@ -242,6 +242,28 @@ grl_local_metadata_source_set_property (GObject      *object,
 
 /* ======================= Utilities ==================== */
 
+static gboolean
+is_nonalnum (const gchar *str)
+{
+  gunichar uchar;
+
+  if (str == NULL) {
+    return FALSE;
+  }
+
+  uchar = g_utf8_get_char (str);
+
+  if (g_unichar_isalnum (uchar)) {
+    return FALSE;
+  }
+
+  if (uchar == '!' || uchar == '?' || uchar == '.') {
+    return FALSE;
+  }
+
+  return TRUE;
+}
+
 static gchar *
 video_sanitise_string (const gchar *str)
 {
@@ -270,22 +292,17 @@ video_sanitise_string (const gchar *str)
   }
 
   if (*line_end != '\0') {
-    line_end = g_utf8_find_prev_char (line, line_end);
-
+    /* After removing substring with blacklisted word, ignore non alpha-numeric
+     * char in the end of the sanitised string */
+    do {
+      line_end = g_utf8_find_prev_char (line, line_end);
+    } while (is_nonalnum (line_end));
 
     /* If everything in the string is blacklisted, just ignore
      * the blackisting logic.
      */
-    if (line_end == NULL)
+    if (line_end == NULL) {
       return g_strdup (str);
-
-    /* After removing substring with blacklisted word, ignore non alpha-numeric
-     * char in the end of the sanitised string */
-    while (g_unichar_isalnum (*line_end) == FALSE &&
-           *line_end != '!' &&
-           *line_end != '?' &&
-           *line_end != '.') {
-      line_end = g_utf8_find_prev_char (line, line_end);
     }
 
     return g_strndup (line, line_end - line);