* Yang "min-element" and "max-element" feature supported

* New Clixon Yang RPC: ping. To check if backup is running.
* Fixed support for multiple datanodes in a choice/case statement.

apps/backend/backend_client.c

@@ -1039,6 +1039,26 @@ from_client_debug(clicon_handle h,
     return retval;
 }
 
+/*! Check liveness of backend daemon,  just send a reply
+ * @param[in]  h       Clicon handle 
+ * @param[in]  xe      Request: <rpc><xn></rpc> 
+ * @param[out] cbret   Return xml tree, eg <rpc-reply>..., <rpc-error.. 
+ * @param[in]  arg     client-entry
+ * @param[in]  regarg  User argument given at rpc_callback_register() 
+ * @retval     0       OK
+ * @retval    -1       Error
+ */
+static int
+from_client_ping(clicon_handle h,
+		 cxobj        *xe,
+		 cbuf         *cbret,
+		 void         *arg,
+		 void         *regarg)
+{
+    cprintf(cbret, "<rpc-reply><ok/></rpc-reply>");
+    return 0;
+}
+
 /*! An internal clicon message has arrived from a client. Receive and dispatch.
  * @param[in]   h    Clicon handle
  * @param[in]   s    Socket where message arrived. read from this.
@@ -1271,10 +1291,13 @@ backend_rpc_init(clicon_handle h)
     if (rpc_callback_register(h, from_client_create_subscription, NULL,
 		      "urn:ietf:params:xml:ns:netmod:notification", "create-subscription") < 0)
 	goto done;
-    /* In backend_client.? Clixon RPC */
+    /* Clixon RPC */
     if (rpc_callback_register(h, from_client_debug, NULL,
 			      "http://clicon.org/lib", "debug") < 0)
 	goto done;
+    if (rpc_callback_register(h, from_client_ping, NULL,
+			      "http://clicon.org/lib", "ping") < 0)
+	goto done;
     retval =0;
  done:
     return retval;

apps/netconf/netconf_main.c

@@ -71,10 +71,13 @@
 #include "netconf_rpc.h"
 
 /* Command line options to be passed to getopt(3) */
-#define NETCONF_OPTS "hD:f:l:qa:u:d:p:y:U:t:o:"
+#define NETCONF_OPTS "hD:f:l:qa:u:d:p:y:U:t:eo:"
 
 #define NETCONF_LOGFILE "/tmp/clixon_netconf.log"
 
+/*! Ignore errors on packet errors: continue */
+static int ignore_packet_errors = 1;
+
 /*! Process incoming packet 
  * @param[in]   h    Clicon handle
  * @param[in]   cb   Packet buffer
@@ -235,8 +238,9 @@ netconf_input_cb(int   s,
 		/* OK, we have an xml string from a client */
 		/* Remove trailer */
 		*(((char*)cbuf_get(cb)) + cbuf_len(cb) - strlen("]]>]]>")) = '\0';
-		if (netconf_input_packet(h, cb) < 0)
-		    ; //goto done; // ignore errors
+		if (netconf_input_packet(h, cb) < 0 &&
+		    !ignore_packet_errors) // default is to ignore errors
+		    goto done; 
 		if (cc_closed)
 		    break;
 		cbuf_reset(cb);
@@ -338,6 +342,7 @@ usage(clicon_handle h,
 	    "\t-y <file>\tLoad yang spec file (override yang main module)\n"
 	    "\t-U <user>\tOver-ride unix user with a pseudo user for NACM.\n"
 	    "\t-t <sec>\tTimeout in seconds. Quit after this time.\n"
+	    "\t-e \tDont ignore errors on packet input.\n"
 	    "\t-o \"<option>=<value>\"\tGive configuration option overriding config file (see clixon-config.yang)\n",
 	    argv0,
 	    clicon_netconf_dir(h)
@@ -349,6 +354,7 @@ int
 main(int    argc,
      char **argv)
 {
+    int              retval = -1;
     int              c;
     char            *argv0 = argv[0];
     int              quiet = 0;
@@ -455,6 +461,9 @@ main(int    argc,
 	case 't': /* timeout in seconds */
 	    tv.tv_sec = atoi(optarg);
 	    break;
+	case 'e': /* dont ignore packet errors */
+	    ignore_packet_errors = 0;
+	    break;
 	case 'o':{ /* Configuration option */
 	    char          *val;
 	    if ((val = index(optarg, '=')) == NULL)
@@ -528,9 +537,12 @@ main(int    argc,
     }
     if (event_loop() < 0)
 	goto done;
+    retval = 0;
   done:
+    if (ignore_packet_errors)
+	retval = 0;
     netconf_terminate(h);
     clicon_log_init(__PROGRAM__, LOG_INFO, 0); /* Log on syslog no stderr */
     clicon_log(LOG_NOTICE, "%s: %u Terminated", __PROGRAM__, getpid());
-    return 0;
+    return retval;
 }

apps/restconf/restconf_methods.c

@@ -588,6 +588,10 @@ api_data_post(clicon_handle h,
 	    goto done;
 	goto ok;
     }
+    if (xretcom){ /* Clear: can be reused again below */
+	xml_free(xretcom);
+	xretcom = NULL;
+    }
     if (if_feature(yspec, "ietf-netconf", "startup")){
 	/* RFC8040 Sec 1.4:
 	 * If the NETCONF server supports :startup, the RESTCONF server MUST
@@ -933,6 +937,10 @@ api_data_put(clicon_handle h,
 	    goto done;
 	goto ok;
     }
+    if (xretcom){ /* Clear: can be reused again below */
+	xml_free(xretcom);
+	xretcom = NULL;
+    }
     if (if_feature(yspec, "ietf-netconf", "startup")){
 	/* RFC8040 Sec 1.4:
 	 * If the NETCONF server supports :startup, the RESTCONF server MUST
@@ -1108,6 +1116,10 @@ api_data_delete(clicon_handle h,
 	    goto done;
 	goto ok;
     }
+    if (xretcom){ /* Clear: can be reused again below */
+	xml_free(xretcom);
+	xretcom = NULL;
+    }
     if (if_feature(yspec, "ietf-netconf", "startup")){
 	/* RFC8040 Sec 1.4:
 	 * If the NETCONF server supports :startup, the RESTCONF server MUST