gtpu_echo: do not osmo_fd_register twice

Change-Id: Ib498cc8d5252c05e12196f84bd1ea18d67e3052c
---
M src/osmo-upf/upf_gtpu_echo.c
1 file changed, 6 insertions(+), 1 deletion(-)


git pull ssh://gerrit.osmocom.org:29418/osmo-upf refs/changes/24/30524/1

diff --git a/src/osmo-upf/upf_gtpu_echo.c b/src/osmo-upf/upf_gtpu_echo.c
index f6dfe5c..60a8da8 100644
--- a/src/osmo-upf/upf_gtpu_echo.c
+++ b/src/osmo-upf/upf_gtpu_echo.c
@@ -155,7 +155,12 @@
 		return -EINVAL;
 	}
 
+	/* the caller should already have osmo_fd_register()ed when setting up the socket. */
+	OSMO_ASSERT(osmo_fd_is_registered(&dev->gtpv1.ofd));
+	/* make sure there is no cb yet that this would be replacing. */
+	OSMO_ASSERT(dev->gtpv1.ofd.cb == NULL);
+
 	dev->gtpv1.ofd.cb = upf_gtpu_echo_read_cb;
 	dev->gtpv1.ofd.data = dev;
-	return osmo_fd_register(&dev->gtpv1.ofd);
+	return 0;
 }

