udev: split libinput_udev context init into two functions

This is preparation work for context-specific log handlers.

Callers are now encouraged to first initialize the context with
libinput_udev_create_context() and then set the seat for this context with
libinput_udev_assign_seat().

In the upcoming patch to support context-specific log handlers this enables a
caller to set the log handler for a context before any devices are
initialized. Otherwise, a log message generated by a new device may pass a
libinput context that the caller is not yet aware of.

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>

1 files changed, 48 insertions, 10 deletions

diff --git a/src/udev-seat.c b/src/udev-seat.c
index 38a13b72..89160ff8 100644
--- a/src/udev-seat.c
+++ b/src/udev-seat.c
@@ -333,14 +333,13 @@ static const struct libinput_interface_backend interface_backend = {
 };
 
 LIBINPUT_EXPORT struct libinput *
-libinput_udev_create_for_seat(const struct libinput_interface *interface,
-			      void *user_data,
-			      struct udev *udev,
-			      const char *seat_id)
+libinput_udev_create_context(const struct libinput_interface *interface,
+			     void *user_data,
+			     struct udev *udev)
 {
 	struct udev_input *input;
 
-	if (!interface || !udev || !seat_id)
+	if (!interface || !udev)
 		return NULL;
 
 	input = zalloc(sizeof *input);
@@ -354,14 +353,53 @@ libinput_udev_create_for_seat(const struct libinput_interface *interface,
 	}
 
 	input->udev = udev_ref(udev);
+
+	return &input->base;
+}
+
+LIBINPUT_EXPORT int
+libinput_udev_assign_seat(struct libinput *libinput,
+			  const char *seat_id)
+{
+	struct udev_input *input = (struct udev_input*)libinput;
+
+	if (!seat_id)
+		return -1;
+	if (input->seat_id != NULL)
+		return -1;
+
+	if (libinput->interface_backend != &interface_backend) {
+		log_bug_client("Mismatching backends.\n");
+		return -1;
+	}
+
 	input->seat_id = strdup(seat_id);
 
-	if (udev_input_enable(&input->base) < 0) {
-		udev_unref(udev);
-		libinput_destroy(&input->base);
-		free(input);
+	if (udev_input_enable(&input->base) < 0)
+		return -1;
+
+	return 0;
+}
+
+LIBINPUT_EXPORT struct libinput *
+libinput_udev_create_for_seat(const struct libinput_interface *interface,
+			      void *user_data,
+			      struct udev *udev,
+			      const char *seat_id)
+{
+	struct libinput *libinput;
+
+	if (!interface || !udev || !seat_id)
 		return NULL;
+
+	libinput = libinput_udev_create_context(interface, user_data, udev);
+	if (!libinput)
+		return NULL;
+
+	if (libinput_udev_assign_seat(libinput, seat_id) != 0) {
+		libinput_destroy(libinput);
+		libinput = NULL;
 	}
 
-	return &input->base;
+	return libinput;
 }