base-modem: allow parallel Enable() and Disable() requests

If additional Enable() requests are received while one is already
ongoing, we queue them and will end up completing all with the same
result once the first one finishes.

Same logic also for Disable().

https://gitlab.freedesktop.org/mobile-broadband/ModemManager/issues/8
(cherry picked from commit c4766122476b53a89c606bd0c0cbbd0ec6d9826b)

2 files changed, 100 insertions, 23 deletions

diff --git a/src/mm-base-modem.c b/src/mm-base-modem.c
index 12e96dc00..fa9303ca8 100644
--- a/src/mm-base-modem.c
+++ b/src/mm-base-modem.c
@@ -89,6 +89,10 @@ struct _MMBaseModemPrivate {
     MMPortSerialAt *gps_control;
     MMPortSerialGps *gps;
 
+    /* Support for parallel enable/disable operations */
+    GList *enable_tasks;
+    GList *disable_tasks;
+
 #if defined WITH_QMI
     /* QMI ports */
     GList *qmi;
@@ -310,49 +314,123 @@ mm_base_modem_grab_port (MMBaseModem         *self,
 }
 
 gboolean
-mm_base_modem_disable_finish (MMBaseModem *self,
-                              GAsyncResult *res,
-                              GError **error)
+mm_base_modem_disable_finish (MMBaseModem   *self,
+                              GAsyncResult  *res,
+                              GError       **error)
 {
-    return MM_BASE_MODEM_GET_CLASS (self)->disable_finish (self, res, error);
+    return g_task_propagate_boolean (G_TASK (res), error);
+}
+
+static void
+disable_ready (MMBaseModem  *self,
+               GAsyncResult *res)
+{
+    GError *error = NULL;
+    GList  *l;
+    GList  *disable_tasks;
+
+    g_assert (self->priv->disable_tasks);
+    disable_tasks = self->priv->disable_tasks;
+    self->priv->disable_tasks = NULL;
+
+    MM_BASE_MODEM_GET_CLASS (self)->disable_finish (self, res, &error);
+    for (l = disable_tasks; l; l = g_list_next (l)) {
+        if (error)
+            g_task_return_error (G_TASK (l->data), g_error_copy (error));
+        else
+            g_task_return_boolean (G_TASK (l->data), TRUE);
+    }
+    g_clear_error (&error);
+
+    g_list_free_full (disable_tasks, (GDestroyNotify)g_object_unref);
 }
 
 void
-mm_base_modem_disable (MMBaseModem *self,
-                      GAsyncReadyCallback callback,
-                      gpointer user_data)
+mm_base_modem_disable (MMBaseModem         *self,
+                       GAsyncReadyCallback  callback,
+                       gpointer             user_data)
 {
+    GTask    *task;
+    gboolean  run_disable;
+
     g_assert (MM_BASE_MODEM_GET_CLASS (self)->disable != NULL);
     g_assert (MM_BASE_MODEM_GET_CLASS (self)->disable_finish != NULL);
 
+    /* If the list of disable tasks is empty, we need to run */
+    run_disable = !self->priv->disable_tasks;
+
+    /* Store task */
+    task = g_task_new (self, self->priv->cancellable, callback, user_data);
+    self->priv->disable_tasks = g_list_append (self->priv->disable_tasks, task);
+
+    if (!run_disable)
+        return;
+
     MM_BASE_MODEM_GET_CLASS (self)->disable (
         self,
         self->priv->cancellable,
-        callback,
-        user_data);
+        (GAsyncReadyCallback) disable_ready,
+        NULL);
 }
 
 gboolean
-mm_base_modem_enable_finish (MMBaseModem *self,
-                             GAsyncResult *res,
-                             GError **error)
+mm_base_modem_enable_finish (MMBaseModem   *self,
+                             GAsyncResult  *res,
+                             GError       **error)
 {
-    return MM_BASE_MODEM_GET_CLASS (self)->enable_finish (self, res, error);
+    return g_task_propagate_boolean (G_TASK (res), error);
+}
+
+static void
+enable_ready (MMBaseModem  *self,
+              GAsyncResult *res)
+{
+    GError *error = NULL;
+    GList  *l;
+    GList  *enable_tasks;
+
+    g_assert (self->priv->enable_tasks);
+    enable_tasks = self->priv->enable_tasks;
+    self->priv->enable_tasks = NULL;
+
+    MM_BASE_MODEM_GET_CLASS (self)->enable_finish (self, res, &error);
+    for (l = enable_tasks; l; l = g_list_next (l)) {
+        if (error)
+            g_task_return_error (G_TASK (l->data), g_error_copy (error));
+        else
+            g_task_return_boolean (G_TASK (l->data), TRUE);
+    }
+    g_clear_error (&error);
+
+    g_list_free_full (enable_tasks, (GDestroyNotify)g_object_unref);
 }
 
 void
-mm_base_modem_enable (MMBaseModem *self,
-                      GAsyncReadyCallback callback,
-                      gpointer user_data)
+mm_base_modem_enable (MMBaseModem         *self,
+                      GAsyncReadyCallback  callback,
+                      gpointer             user_data)
 {
+    GTask    *task;
+    gboolean  run_enable;
+
     g_assert (MM_BASE_MODEM_GET_CLASS (self)->enable != NULL);
     g_assert (MM_BASE_MODEM_GET_CLASS (self)->enable_finish != NULL);
 
+    /* If the list of enable tasks is empty, we need to run */
+    run_enable = !self->priv->enable_tasks;
+
+    /* Store task */
+    task = g_task_new (self, self->priv->cancellable, callback, user_data);
+    self->priv->enable_tasks = g_list_append (self->priv->enable_tasks, task);
+
+    if (!run_enable)
+        return;
+
     MM_BASE_MODEM_GET_CLASS (self)->enable (
         self,
         self->priv->cancellable,
-        callback,
-        user_data);
+        (GAsyncReadyCallback) enable_ready,
+        NULL);
 }
 
 gboolean
@@ -1417,6 +1495,9 @@ finalize (GObject *object)
      * mm_auth_provider_cancel_for_owner (self->priv->authp, object);
     */
 
+    g_assert (!self->priv->enable_tasks);
+    g_assert (!self->priv->disable_tasks);
+
     mm_dbg ("Modem (%s) '%s' completely disposed",
             self->priv->plugin,
             self->priv->device);
diff --git a/src/mm-broadband-modem.c b/src/mm-broadband-modem.c
index 8afec66f9..8c0835661 100644
--- a/src/mm-broadband-modem.c
+++ b/src/mm-broadband-modem.c
@@ -10006,11 +10006,7 @@ enable (MMBaseModem *self,
         break;
 
     case MM_MODEM_STATE_ENABLING:
-        g_task_return_new_error (task,
-                                 MM_CORE_ERROR,
-                                 MM_CORE_ERROR_IN_PROGRESS,
-                                 "Cannot enable modem: "
-                                 "already being enabled");
+        g_assert_not_reached ();
         break;
 
     case MM_MODEM_STATE_ENABLED: