module-flatpak: keep track of pending async checksflatpack

Keep a list of pending async requests indexed by the DBus path name.
When we get a reply, we can find the associated access_data again
and complete the check.
Cancel the portal request when the free callback is called. This can
happen when the client disconnects while we are waiting for the reply.

1 files changed, 80 insertions, 4 deletions

diff --git a/src/modules/module-flatpak.c b/src/modules/module-flatpak.c
index c7a568814..a5b76b8e4 100644
--- a/src/modules/module-flatpak.c
+++ b/src/modules/module-flatpak.c
@@ -93,6 +93,14 @@ struct userdata {
     pa_hashmap *clients;
 };
 
+struct async_pending {
+    PA_LLIST_FIELDS(struct async_pending);
+    bool handled;
+    struct client_data *client_data;
+    char *handle;
+    pa_access_data *access_data;
+};
+
 struct client_data {
     struct userdata *u;
 
@@ -101,11 +109,66 @@ struct client_data {
     pid_t pid;
 
     struct async_cache cached[PA_ACCESS_HOOK_MAX];
-    pa_access_data *access_data;
 
     PA_LLIST_HEAD(struct visible_object, visible_objects);
+    PA_LLIST_HEAD(struct async_pending, pending);
 };
 
+static void close_request(struct async_pending *p) {
+    DBusMessage *m = NULL;
+    struct userdata *u = p->client_data->u;
+
+    if (!(m = dbus_message_new_method_call("org.freedesktop.portal.Request",
+                                           p->handle,
+                                           "org.freedesktop.portal.Request",
+                                           "Close"))) {
+        pa_log_error("Failed to create message\n");
+        return;
+    }
+
+    if (!dbus_connection_send(pa_dbus_connection_get(u->connection), m, NULL))
+        pa_log_error("Failed to send message\n");
+
+    dbus_message_unref(m);
+}
+
+static void free_pending(void *userdata) {
+    struct async_pending *p = userdata;
+    struct client_data *cd = p->client_data;
+
+    if (!p->handled)
+        close_request(p);
+
+    PA_LLIST_REMOVE(struct async_pending, cd->pending, p);
+    pa_xfree(p->handle);
+    pa_xfree(p);
+}
+
+static void add_pending(struct client_data *cd, const char *handle, pa_access_data *access_data) {
+    struct async_pending *p;
+
+    p = pa_xnew0(struct async_pending, 1);
+    PA_LLIST_INIT(struct async_pending, p);
+    p->client_data = cd;
+    p->handle = pa_xstrdup(handle);
+    p->access_data = access_data;
+    p->handled = false;
+
+    access_data->userdata = p;
+    access_data->free_cb = free_pending;
+
+    PA_LLIST_PREPEND(struct async_pending, cd->pending, p);
+}
+
+static struct async_pending *find_pending(struct client_data *cd, const char *handle) {
+    struct async_pending *p;
+
+    PA_LLIST_FOREACH(p, cd->pending) {
+        if (pa_streq(p->handle, handle))
+            return p;
+    }
+    return NULL;
+}
 
 static void add_object(struct client_data *cd, int facility, uint32_t oidx) {
     struct visible_object *o;
@@ -158,10 +221,14 @@ static struct client_data * client_data_new(struct userdata *u, uint32_t index,
 
 static void client_data_free(struct client_data *cd) {
     struct visible_object *o;
+    struct async_pending *p;
 
     while ((o = cd->visible_objects))
         free_object(cd, o);
 
+    while ((p = cd->pending))
+        free_pending(p);
+
     pa_log_debug("removed client %d", cd->index);
     pa_xfree(cd);
 }
@@ -227,11 +294,12 @@ static pa_access_result_t rule_block (pa_core *c, pa_access_data *d, void *u) {
 
 static DBusHandlerResult portal_response(DBusConnection *connection, DBusMessage *msg, void *user_data) {
     struct client_data *cd = user_data;
-    pa_access_data *d = cd->access_data;
 
     if (dbus_message_is_signal(msg, "org.freedesktop.portal.Request", "Response")) {
         uint32_t response = 2;
         DBusError error;
+        struct async_pending *p;
+        pa_access_data *d;
 
         dbus_error_init(&error);
 
@@ -242,6 +310,13 @@ static DBusHandlerResult portal_response(DBusConnection *connection, DBusMessage
             dbus_error_free(&error);
         }
 
+        p = find_pending(cd, dbus_message_get_path(msg));
+        if (p == NULL)
+            return DBUS_HANDLER_RESULT_HANDLED;
+
+        p->handled = true;
+        d = p->access_data;
+
         cd->cached[d->hook].checked = true;
         cd->cached[d->hook].result = response == 0 ? PA_ACCESS_GRANTED : PA_ACCESS_DENIED;
 
@@ -273,14 +348,13 @@ static pa_access_result_t rule_check_portal (pa_core *c, pa_access_data *d, void
 
     pa_log_info("ask portal for operation %d/%d for client %d", d->hook, d->object_index, d->client_index);
 
-    cd->access_data = d;
-
     dbus_error_init(&error);
 
     if (!(m = dbus_message_new_method_call("org.freedesktop.portal.Desktop",
                                            "/org/freedesktop/portal/desktop",
                                            "org.freedesktop.portal.Device",
                                            "AccessDevice"))) {
+        pa_log_error("Failed to create message\n");
         return PA_ACCESS_DENIED;
     }
 
@@ -338,6 +412,8 @@ static pa_access_result_t rule_check_portal (pa_core *c, pa_access_data *d, void
 
     dbus_connection_add_filter(pa_dbus_connection_get(u->connection), portal_response, cd, NULL);
 
+    add_pending(cd, handle, d);
+
     return PA_ACCESS_ASYNC_CHECK;
 }