document: add destroy notify to page callback

This ensures that we only free the async data struct when the document is
guaranteed to be done calling our callback. Without this, we risk
potentially accessing the async request data after we have freed it
when a mallard document reloads.

https://bugzilla.gnome.org/show_bug.cgi?id=778258

9 files changed, 53 insertions, 25 deletions

diff --git a/libyelp/yelp-docbook-document.c b/libyelp/yelp-docbook-document.c
index 4ac09a97..9b430b09 100644
--- a/libyelp/yelp-docbook-document.c
+++ b/libyelp/yelp-docbook-document.c
@@ -60,7 +60,8 @@ static gboolean       docbook_request_page      (YelpDocument         *document,
                                                  const gchar          *page_id,
                                                  GCancellable         *cancellable,
                                                  YelpDocumentCallback  callback,
-                                                 gpointer              user_data);
+                                                 gpointer              user_data,
+                                                 GDestroyNotify        notify);
 
 static void           docbook_process           (YelpDocbookDocument  *docbook);
 static void           docbook_disconnect        (YelpDocbookDocument  *docbook);
@@ -239,7 +240,8 @@ docbook_request_page (YelpDocument         *document,
                       const gchar          *page_id,
                       GCancellable         *cancellable,
                       YelpDocumentCallback  callback,
-                      gpointer              user_data)
+                      gpointer              user_data,
+                      GDestroyNotify        notify)
 {
     YelpDocbookDocumentPrivate *priv = GET_PRIV (document);
     gchar *docuri;
@@ -257,7 +259,8 @@ docbook_request_page (YelpDocument         *document,
                                                                                 page_id,
                                                                                 cancellable,
                                                                                 callback,
-                                                                                user_data);
+                                                                                user_data,
+                                                                                notify);
     if (handled) {
         return handled;
     }
diff --git a/libyelp/yelp-document.c b/libyelp/yelp-document.c
index f26ebd2b..547ef24d 100644
--- a/libyelp/yelp-document.c
+++ b/libyelp/yelp-document.c
@@ -51,6 +51,7 @@ struct _Request {
     GCancellable         *cancellable;
     YelpDocumentCallback  callback;
     gpointer              user_data;
+    GDestroyNotify        notify;
     GError               *error;
 
     gint                  idle_funcs;
@@ -113,7 +114,8 @@ static gboolean       document_request_page     (YelpDocument         *document,
                                                  const gchar          *page_id,
                                                  GCancellable         *cancellable,
                                                  YelpDocumentCallback  callback,
-                                                 gpointer              user_data);
+                                                 gpointer              user_data,
+                                                 GDestroyNotify        notify);
 static gboolean       document_indexed          (YelpDocument         *document);
 static const gchar *  document_read_contents    (YelpDocument         *document,
                                                  const gchar          *page_id);
@@ -810,7 +812,8 @@ yelp_document_request_page (YelpDocument         *document,
 			    const gchar          *page_id,
 			    GCancellable         *cancellable,
 			    YelpDocumentCallback  callback,
-			    gpointer              user_data)
+			    gpointer              user_data,
+			    GDestroyNotify        notify)
 {
     g_return_val_if_fail (YELP_IS_DOCUMENT (document), FALSE);
     g_return_val_if_fail (YELP_DOCUMENT_GET_CLASS (document)->request_page != NULL, FALSE);
@@ -821,7 +824,8 @@ yelp_document_request_page (YelpDocument         *document,
 							     page_id,
 							     cancellable,
 							     callback,
-							     user_data);
+							     user_data,
+							     notify);
 }
 
 static gboolean
@@ -829,7 +833,8 @@ document_request_page (YelpDocument         *document,
 		       const gchar          *page_id,
 		       GCancellable         *cancellable,
 		       YelpDocumentCallback  callback,
-		       gpointer              user_data)
+		       gpointer              user_data,
+		       GDestroyNotify        notify)
 {
     Request *request;
     gchar *real_id;
@@ -855,6 +860,7 @@ document_request_page (YelpDocument         *document,
 
     request->callback = callback;
     request->user_data = user_data;
+    request->notify = notify;
     request->idle_funcs = 0;
 
     g_mutex_lock (&document->priv->mutex);
@@ -1510,6 +1516,9 @@ request_try_free (Request *request)
 static void
 request_free (Request *request)
 {
+    if (request->notify)
+        request->notify (request->user_data);
+
     g_object_unref (request->document);
     g_free (request->page_id);
     g_object_unref (request->cancellable);
diff --git a/libyelp/yelp-document.h b/libyelp/yelp-document.h
index 75157d5a..175b281a 100644
--- a/libyelp/yelp-document.h
+++ b/libyelp/yelp-document.h
@@ -63,7 +63,8 @@ struct _YelpDocumentClass {
                                                      const gchar          *page_id,
                                                      GCancellable         *cancellable,
                                                      YelpDocumentCallback  callback,
-                                                     gpointer              user_data);
+                                                     gpointer              user_data,
+                                                     GDestroyNotify        notify);
     const gchar * (*read_contents)                  (YelpDocument         *document,
                                                      const gchar          *page_id);
     void          (*finish_read)                    (YelpDocument         *document,
@@ -85,7 +86,8 @@ gboolean          yelp_document_request_page        (YelpDocument         *docum
                                                      const gchar          *page_id,
                                                      GCancellable         *cancellable,
                                                      YelpDocumentCallback  callback,
-                                                     gpointer              user_data);
+                                                     gpointer              user_data,
+                                                     GDestroyNotify        notify);
 void              yelp_document_clear_contents      (YelpDocument         *document);
 gchar **          yelp_document_get_requests        (YelpDocument         *document);
 
diff --git a/libyelp/yelp-help-list.c b/libyelp/yelp-help-list.c
index f5020229..9005e48f 100644
--- a/libyelp/yelp-help-list.c
+++ b/libyelp/yelp-help-list.c
@@ -43,7 +43,8 @@ static gboolean       help_list_request_page         (YelpDocument          *doc
                                                       const gchar           *page_id,
                                                       GCancellable          *cancellable,
                                                       YelpDocumentCallback   callback,
-                                                      gpointer               user_data);
+                                                      gpointer               user_data,
+                                                      GDestroyNotify         notify);
 static void           help_list_think                (YelpHelpList          *list);
 static void           help_list_handle_page          (YelpHelpList          *list,
                                                       const gchar           *page_id);
@@ -179,7 +180,8 @@ help_list_request_page (YelpDocument          *document,
                         const gchar           *page_id,
                         GCancellable          *cancellable,
                         YelpDocumentCallback   callback,
-                        gpointer               user_data)
+                        gpointer               user_data,
+                        GDestroyNotify         notify)
 {
     gboolean handled;
     YelpHelpListPrivate *priv = GET_PRIV (document);
@@ -192,7 +194,8 @@ help_list_request_page (YelpDocument          *document,
                                                                          page_id,
                                                                          cancellable,
                                                                          callback,
-                                                                         user_data);
+                                                                         user_data,
+                                                                         notify);
     if (handled) {
         return TRUE;
     }
diff --git a/libyelp/yelp-info-document.c b/libyelp/yelp-info-document.c
index b6f50771..7b532744 100644
--- a/libyelp/yelp-info-document.c
+++ b/libyelp/yelp-info-document.c
@@ -75,7 +75,8 @@ static gboolean       info_request_page                   (YelpDocument
                                                            const gchar          *page_id,
                                                            GCancellable         *cancellable,
                                                            YelpDocumentCallback  callback,
-                                                           gpointer              user_data);
+                                                           gpointer              user_data,
+                                                           GDestroyNotify        notify);
 
 /* YelpTransform */
 static void           transform_chunk_ready     (YelpTransform        *transform,
@@ -178,7 +179,8 @@ info_request_page (YelpDocument         *document,
                    const gchar          *page_id,
                    GCancellable         *cancellable,
                    YelpDocumentCallback  callback,
-                   gpointer              user_data)
+                   gpointer              user_data,
+                   GDestroyNotify        notify)
 {
     YelpInfoDocumentPrivate *priv = GET_PRIV (document);
     gchar *docuri;
@@ -193,7 +195,8 @@ info_request_page (YelpDocument         *document,
                                                                              page_id,
                                                                              cancellable,
                                                                              callback,
-                                                                             user_data);
+                                                                             user_data,
+                                                                             notify);
     if (handled) {
         return TRUE;
     }
diff --git a/libyelp/yelp-mallard-document.c b/libyelp/yelp-mallard-document.c
index e42f40b4..f0713078 100644
--- a/libyelp/yelp-mallard-document.c
+++ b/libyelp/yelp-mallard-document.c
@@ -79,7 +79,8 @@ static gboolean       mallard_request_page      (YelpDocument         *document,
                                                  const gchar          *page_id,
                                                  GCancellable         *cancellable,
                                                  YelpDocumentCallback  callback,
-                                                 gpointer              user_data);
+                                                 gpointer              user_data,
+                                                 GDestroyNotify        notify);
 
 static void           transform_chunk_ready     (YelpTransform        *transform,
                                                  gchar                *chunk_id,
@@ -250,7 +251,8 @@ mallard_request_page (YelpDocument         *document,
                       const gchar          *page_id,
                       GCancellable         *cancellable,
                       YelpDocumentCallback  callback,
-                      gpointer              user_data)
+                      gpointer              user_data,
+                      GDestroyNotify        notify)
 {
     YelpMallardDocumentPrivate *priv = GET_PRIV (document);
     gchar *docuri;
@@ -268,7 +270,8 @@ mallard_request_page (YelpDocument         *document,
                                                                                 page_id,
                                                                                 cancellable,
                                                                                 callback,
-                                                                                user_data);
+                                                                                user_data,
+                                                                                notify);
     if (handled) {
         return TRUE;
     }
diff --git a/libyelp/yelp-man-document.c b/libyelp/yelp-man-document.c
index 77e74143..4e165d57 100644
--- a/libyelp/yelp-man-document.c
+++ b/libyelp/yelp-man-document.c
@@ -124,7 +124,8 @@ static gboolean       man_request_page                   (YelpDocument
                                                           const gchar            *page_id,
                                                           GCancellable           *cancellable,
                                                           YelpDocumentCallback    callback,
-                                                          gpointer                user_data);
+                                                          gpointer                user_data,
+                                                          GDestroyNotify          notify);
 
 /* YelpTransform */
 static void           transform_chunk_ready              (YelpTransform          *transform,
@@ -203,7 +204,8 @@ man_request_page (YelpDocument         *document,
                   const gchar          *page_id,
                   GCancellable         *cancellable,
                   YelpDocumentCallback  callback,
-                  gpointer              user_data)
+                  gpointer              user_data,
+                  GDestroyNotify        notify)
 {
     YelpManDocumentPrivate *priv = GET_PRIV (document);
     gchar *docuri, *fulluri;
@@ -222,7 +224,8 @@ man_request_page (YelpDocument         *document,
                                                                             page_id,
                                                                             cancellable,
                                                                             callback,
-                                                                            user_data);
+                                                                            user_data,
+                                                                            notify);
     if (handled) {
         return handled;
     }
diff --git a/libyelp/yelp-simple-document.c b/libyelp/yelp-simple-document.c
index 47145621..501d7881 100644
--- a/libyelp/yelp-simple-document.c
+++ b/libyelp/yelp-simple-document.c
@@ -66,7 +66,8 @@ static gboolean       document_request_page            (YelpDocument
 							const gchar             *page_id,
 							GCancellable            *cancellable,
 							YelpDocumentCallback     callback,
-							gpointer                 user_data);
+							gpointer                 user_data,
+							GDestroyNotify           notify);
 static const gchar *  document_read_contents           (YelpDocument            *document,
 							const gchar             *page_id);
 static void           document_finish_read             (YelpDocument            *document,
@@ -181,7 +182,8 @@ document_request_page (YelpDocument         *document,
 		       const gchar          *page_id,
 		       GCancellable         *cancellable,
 		       YelpDocumentCallback  callback,
-		       gpointer              user_data)
+		       gpointer              user_data,
+		       GDestroyNotify        notify)
 {
     YelpSimpleDocument *simple = YELP_SIMPLE_DOCUMENT (document);
     Request *request;
diff --git a/libyelp/yelp-view.c b/libyelp/yelp-view.c
index 0e0d1d3f..c4432217 100644
--- a/libyelp/yelp-view.c
+++ b/libyelp/yelp-view.c
@@ -787,7 +787,6 @@ document_callback (YelpDocument       *document,
                                       stream,
                                       content_length,
                                       mime_type);
-    request_async_data_free (data);
     g_free (mime_type);
     g_object_unref (stream);
 }
@@ -810,7 +809,8 @@ help_cb_uri_resolved (YelpUri                *uri,
                                     data->page_id,
                                     NULL,
                                     (YelpDocumentCallback) document_callback,
-                                    data);
+                                    data,
+                                    (GDestroyNotify) request_async_data_free);
         g_object_unref (document);
 
     } else {