[gnome-autoar] Revert "mime-types: use g_content_type_is_a for mime support"

[Carlos Soriano <csoriano src gnome org>]

commit 578aeeceaa22bd75482f7ae14555655ba0fa8e7e
Author: Carlos Soriano <csoriano gnome org>
Date:   Tue Mar 21 12:50:21 2017 +0100

    Revert "mime-types: use g_content_type_is_a for mime support"
    
    This reverts d7e45a2627d026b86aa518984fad48b5ff76ffb8
    
    It gives more problems than it solves. For example docx is a subtype of zip,
    which makes autoar report it as supported, when it's not.
    
    So it's better to use the subtypes that autoar supports directly.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=780214

 gnome-autoar/autoar-mime-types.c |   29 ++++++++++++++++++++---------
 1 files changed, 20 insertions(+), 9 deletions(-)
---
diff --git a/gnome-autoar/autoar-mime-types.c b/gnome-autoar/autoar-mime-types.c
index fd86bdb..9c8c46f 100644
--- a/gnome-autoar/autoar-mime-types.c
+++ b/gnome-autoar/autoar-mime-types.c
@@ -37,8 +37,25 @@ static gchar *supported_mime_types[] = {
   "application/x-xz",
   "application/zip",
   "application/gzip",
+  NULL
 };
 
+static GHashTable *supported_mime_types_table = NULL;
+
+static void
+initialize_supported_mime_types_table (void)
+{
+  int i;
+
+  supported_mime_types_table = g_hash_table_new (g_str_hash,
+                                                 g_str_equal);
+
+  for (i = 0; supported_mime_types[i] != NULL; ++i) {
+    g_hash_table_add (supported_mime_types_table,
+                      supported_mime_types[i]);
+  }
+}
+
 /**
  * autoar_check_mime_type_supported:
  * @mime_type: a string representing the mime type
@@ -51,17 +68,11 @@ static gchar *supported_mime_types[] = {
 gboolean
 autoar_check_mime_type_supported (const gchar *mime_type)
 {
-  gint i;
-  gboolean supported = FALSE;
-
-  for (i = 0; i < G_N_ELEMENTS (supported_mime_types); i++) {
-    if (g_content_type_is_a (mime_type, supported_mime_types[i])) {
-      supported = TRUE;
-      break;
-    }
+  if (supported_mime_types_table == NULL) {
+    initialize_supported_mime_types_table ();
   }
 
-  return supported;
+  return g_hash_table_contains (supported_mime_types_table, mime_type);
 }
 
 /**