silent call: clarify rc and error messages logged on vty

In gsm_silent_call_{start,stop}(), return meaningful error codes and interpret
them on the VTY to clearly indicate the result.

Change-Id: Id5abb8f2ba901689e03040af8e51483b6c618e7f

2 files changed, 40 insertions, 17 deletions

diff --git a/src/libmsc/silent_call.c b/src/libmsc/silent_call.c
index f3291d77f..1ea2305ed 100644
--- a/src/libmsc/silent_call.c
+++ b/src/libmsc/silent_call.c
@@ -30,6 +30,7 @@
 #include <osmocom/msc/gsm_data.h>
 #include <osmocom/msc/gsm_subscriber.h>
 #include <osmocom/msc/osmo_msc.h>
+#include <osmocom/msc/vlr.h>
 
 /* paging of the requested subscriber has completed */
 static int paging_cb_silent(unsigned int hooknum, unsigned int event,
@@ -130,7 +131,9 @@ int gsm_silent_call_start(struct vlr_subscr *vsub, void *data, int type)
 	 * A-interface. */
 	req = subscr_request_conn(vsub, paging_cb_silent, data,
 				  "establish silent call");
-	return req != NULL;
+	if (!req)
+		return -ENODEV;
+	return 0;
 }
 
 /* end a silent call with a given subscriber */
@@ -139,12 +142,18 @@ int gsm_silent_call_stop(struct vlr_subscr *vsub)
 	struct gsm_subscriber_connection *conn;
 
 	conn = connection_for_subscr(vsub);
-	if (!conn)
-		return -EINVAL;
+	if (!conn) {
+		LOGP(DMM, LOGL_ERROR, "%s: Cannot stop silent call, no connection for subscriber\n",
+		     vlr_subscr_name(vsub));
+		return -ENODEV;
+	}
 
 	/* did we actually establish a silent call for this guy? */
-	if (!conn->silent_call)
-		return -EINVAL;
+	if (!conn->silent_call) {
+		LOGP(DMM, LOGL_ERROR, "%s: Cannot stop silent call, subscriber has no active silent call\n",
+		     vlr_subscr_name(vsub));
+		return -ENOENT;
+	}
 
 #if BEFORE_MSCSPLIT
 	/* Re-enable this log output once we can obtain this information via
diff --git a/src/libmsc/vty_interface_layer3.c b/src/libmsc/vty_interface_layer3.c
index 06a426765..05f5b63cf 100644
--- a/src/libmsc/vty_interface_layer3.c
+++ b/src/libmsc/vty_interface_layer3.c
@@ -524,16 +524,20 @@ DEFUN(subscriber_silent_call_start,
 		type = RSL_CHANNEED_ANY;	/* Defaults to ANY */
 
 	rc = gsm_silent_call_start(vsub, vty, type);
-	if (rc <= 0) {
-		vty_out(vty, "%% Subscriber not attached%s",
-			VTY_NEWLINE);
-		vlr_subscr_put(vsub);
-		return CMD_WARNING;
+	switch (rc) {
+	case -ENODEV:
+		vty_out(vty, "%% Subscriber not attached%s", VTY_NEWLINE);
+		break;
+	default:
+		if (rc)
+			vty_out(vty, "%% Cannot start silent call (rc=%d)%s", rc, VTY_NEWLINE);
+		else
+			vty_out(vty, "%% Silent call initiated%s", VTY_NEWLINE);
+		break;
 	}
 
 	vlr_subscr_put(vsub);
-
-	return CMD_SUCCESS;
+	return rc ? CMD_WARNING : CMD_SUCCESS;
 }
 
 DEFUN(subscriber_silent_call_stop,
@@ -553,14 +557,24 @@ DEFUN(subscriber_silent_call_stop,
 	}
 
 	rc = gsm_silent_call_stop(vsub);
-	if (rc < 0) {
-		vlr_subscr_put(vsub);
-		return CMD_WARNING;
+	switch (rc) {
+	case -ENODEV:
+		vty_out(vty, "%% No active connection for subscriber%s", VTY_NEWLINE);
+		break;
+	case -ENOENT:
+		vty_out(vty, "%% Subscriber has no silent call active%s",
+			VTY_NEWLINE);
+		break;
+	default:
+		if (rc)
+			vty_out(vty, "%% Cannot stop silent call (rc=%d)%s", rc, VTY_NEWLINE);
+		else
+			vty_out(vty, "%% Silent call stopped%s", VTY_NEWLINE);
+		break;
 	}
 
 	vlr_subscr_put(vsub);
-
-	return CMD_SUCCESS;
+	return rc ? CMD_WARNING : CMD_SUCCESS;
 }
 
 DEFUN(subscriber_ussd_notify,