api,modem: new 'SetPrimarySimSlot' method

This new method allows changing the SIM slot considered as primary,
when the modem supports multiple SIM slots.

The generic handling of this method will make sure that the modem
object and all its SIM objects are re-probed from scratch as soon as a
successful SIM slot switch happens.

Implementations may report MM_CORE_ERROR_EXISTS when the switch
doesn't need to happen (e.g. if the requested SIM slot is already the
active one).

src/mm-iface-modem.c

@@ -957,6 +957,117 @@ handle_list_bearers (MmGdbusModem *skeleton,
 
 /*****************************************************************************/
 
+typedef struct {
+    MmGdbusModem          *skeleton;
+    GDBusMethodInvocation *invocation;
+    MMIfaceModem          *self;
+    guint                  requested_sim_slot;
+} HandleSetPrimarySimSlotContext;
+
+static void
+handle_set_primary_sim_slot_context_free (HandleSetPrimarySimSlotContext *ctx)
+{
+    g_clear_object (&ctx->skeleton);
+    g_clear_object (&ctx->invocation);
+    g_clear_object (&ctx->self);
+    g_free (ctx);
+}
+
+static void
+set_primary_sim_slot_ready (MMIfaceModem                   *self,
+                            GAsyncResult                   *res,
+                            HandleSetPrimarySimSlotContext *ctx)
+{
+    g_autoptr(GError) error = NULL;
+
+    if (!MM_IFACE_MODEM_GET_INTERFACE (self)->set_primary_sim_slot_finish (self, res, &error)) {
+        /* If the implementation returns EXISTS, we're already in the requested SIM slot,
+         * so we can safely return a success on the operation and skip the reprobing */
+        if (!g_error_matches (error, MM_CORE_ERROR, MM_CORE_ERROR_EXISTS)) {
+            mm_obj_warn (self, "couldn't process primary SIM update request: %s", error->message);
+            g_dbus_method_invocation_take_error (ctx->invocation, g_steal_pointer (&error));
+            handle_set_primary_sim_slot_context_free (ctx);
+            return;
+        }
+        mm_obj_dbg (self, "ignoring SIM update request: %s", error->message);
+    } else {
+        /* Notify about the SIM swap, which will disable and reprobe the device.
+         * There is no need to update the PrimarySimSlot property, as this value will be
+         * reloaded automatically during the reprobe. */
+        mm_base_modem_process_sim_switch (MM_BASE_MODEM (self));
+    }
+
+    mm_gdbus_modem_complete_set_primary_sim_slot (ctx->skeleton, ctx->invocation);
+    handle_set_primary_sim_slot_context_free (ctx);
+}
+
+static void
+handle_set_primary_sim_slot_auth_ready (MMBaseModem                    *self,
+                                        GAsyncResult                   *res,
+                                        HandleSetPrimarySimSlotContext *ctx)
+{
+    GError             *error = NULL;
+    const gchar *const *sim_slot_paths;
+
+    if (!mm_base_modem_authorize_finish (self, res, &error)) {
+        g_dbus_method_invocation_take_error (ctx->invocation, error);
+        handle_set_primary_sim_slot_context_free (ctx);
+        return;
+    }
+
+    /* If SIM switching is not implemented, report an error */
+    if (!MM_IFACE_MODEM_GET_INTERFACE (self)->set_primary_sim_slot ||
+        !MM_IFACE_MODEM_GET_INTERFACE (self)->set_primary_sim_slot_finish) {
+        g_dbus_method_invocation_return_error (ctx->invocation,
+                                               MM_CORE_ERROR,
+                                               MM_CORE_ERROR_UNSUPPORTED,
+                                               "Cannot switch sim: "
+                                               "operation not supported");
+        handle_set_primary_sim_slot_context_free (ctx);
+        return;
+    }
+
+    /* Validate SIM slot number */
+    sim_slot_paths = mm_gdbus_modem_get_sim_slots (ctx->skeleton);
+    if (ctx->requested_sim_slot > g_strv_length ((gchar **)sim_slot_paths)) {
+        g_dbus_method_invocation_return_error (ctx->invocation,
+                                               MM_CORE_ERROR,
+                                               MM_CORE_ERROR_INVALID_ARGS,
+                                               "Cannot switch sim: requested SIM slot number is out of bounds");
+        handle_set_primary_sim_slot_context_free (ctx);
+        return;
+    }
+
+    MM_IFACE_MODEM_GET_INTERFACE (self)->set_primary_sim_slot (MM_IFACE_MODEM (self),
+                                                               ctx->requested_sim_slot,
+                                                               (GAsyncReadyCallback)set_primary_sim_slot_ready,
+                                                               ctx);
+}
+
+static gboolean
+handle_set_primary_sim_slot (MmGdbusModem          *skeleton,
+                             GDBusMethodInvocation *invocation,
+                             guint                  sim_slot,
+                             MMIfaceModem          *self)
+{
+    HandleSetPrimarySimSlotContext *ctx;
+
+    ctx = g_new0 (HandleSetPrimarySimSlotContext, 1);
+    ctx->skeleton = g_object_ref (skeleton);
+    ctx->invocation = g_object_ref (invocation);
+    ctx->self = g_object_ref (self);
+    ctx->requested_sim_slot = sim_slot;
+
+    mm_base_modem_authorize (MM_BASE_MODEM (self),
+                             invocation,
+                             MM_AUTHORIZATION_DEVICE_CONTROL,
+                             (GAsyncReadyCallback)handle_set_primary_sim_slot_auth_ready,
+                             ctx);
+    return TRUE;
+}
+
+/*****************************************************************************/
+
 void
 mm_iface_modem_update_access_technologies (MMIfaceModem *self,
                                            MMModemAccessTechnology new_access_tech,
@@ -5362,6 +5473,7 @@ interface_initialization_step (GTask *task)
                           "signal::handle-enable",                   G_CALLBACK (handle_enable),                   self,
                           "signal::handle-set-current-bands",        G_CALLBACK (handle_set_current_bands),        self,
                           "signal::handle-set-current-modes",        G_CALLBACK (handle_set_current_modes),        self,
+                          "signal::handle-set-primary-sim-slot",     G_CALLBACK (handle_set_primary_sim_slot),     self,
                           NULL);
 
         /* Finally, export the new interface, even if we got errors, but only if not

src/mm-iface-modem.h

@@ -354,6 +354,15 @@ struct _MMIfaceModem {
                                         guint                *primary_sim_slot,
                                         GError              **error);
 
+    /* Set primary SIM slot */
+    void     (* set_primary_sim_slot)        (MMIfaceModem         *self,
+                                              guint                 sim_slot,
+                                              GAsyncReadyCallback   callback,
+                                              gpointer              user_data);
+    gboolean (* set_primary_sim_slot_finish) (MMIfaceModem         *self,
+                                              GAsyncResult         *res,
+                                              GError              **error);
+
     /* Create bearer */
     void (*create_bearer) (MMIfaceModem *self,
                            MMBearerProperties *properties,