library/Osmocom_CTRL_Functions.ttcn

module Osmocom_CTRL_Functions {

/* Definition of helper functions for the Osmocom CTRL interface.
 *
 * As opposed to many other parts of the Osmocom TTCN-3 code base, this module
 * implements blocking functions, instead of asynchronous functions.  The
 * rationale for this is simple: One normally wants to inquire a value or set
 * a value and not continue the main program until that operation is complete.
 *
 * CTRL is a machine-type protocol on how external programs can interact with
 * an Osmocom program in a structured way.  It is intended for programmatic
 * access (by other software), as opposed to the VTY interface intended for
 * human consumption.
 *
 * (C) 2017 by Harald Welte <laforge@gnumonks.org>
 * All rights reserved.
 *
 * Released under the terms of GNU General Public License, Version 2 or
 * (at your option) any later version.
 */


	import from Osmocom_CTRL_Types all;
	import from IPA_Emulation all;

	private function f_gen_rand_id() return CtrlId {
		return int2str(float2int(rnd()*999999999.0));
	}

	/* perform a given GET Operation */
	function f_ctrl_get(IPA_CTRL_PT pt, CtrlVariable variable) return CtrlValue {
		timer T := 2.0;
		var CtrlMessage rx;
		var CtrlId id := f_gen_rand_id();
		pt.send(ts_CtrlMsgGet(id, variable));
		T.start;
		alt {
		[] pt.receive(tr_CtrlMsgGetRepl(id, variable)) -> value rx {
			}
		[] pt.receive(tr_CtrlMsgTrap) { repeat; }
		[] pt.receive(tr_CtrlMsgError) -> value rx {
			setverdict(fail, "Error in CTRL GET ", variable, ": ", rx.err.reason);
			mtc.stop;
			}
		[] T.timeout {
			setverdict(fail, "Timeout waiting for CTRL GET REPLY ", variable);
			mtc.stop;
			}
		}
		return rx.resp.val;
	}

	/* perform a given SET Operation */
	function f_ctrl_set(IPA_CTRL_PT pt, CtrlVariable variable, CtrlValue val) {
		timer T := 2.0;
		var CtrlMessage rx;
		var CtrlId id := f_gen_rand_id();
		pt.send(ts_CtrlMsgSet(id, variable, val));
		T.start;
		alt {
		[] pt.receive(tr_CtrlMsgSetRepl(id, variable, val)) { }
		[] pt.receive(tr_CtrlMsgTrap) { repeat; }
		[] pt.receive(tr_CtrlMsgError) -> value rx {
			setverdict(fail, "Error in CTRL GET ", variable, ": ", rx.err.reason);
			mtc.stop;
			}
		[] T.timeout {
			setverdict(fail, "Timeout waiting for CTRL SET REPLY ", variable);
			mtc.stop;
			}
		}
	}

	/* send a TRAP */
	function f_ctrl_trap(IPA_CTRL_PT pt, CtrlVariable variable, CtrlValue val) {
		pt.send(ts_CtrlMsgTrap(variable, val));
	}

	/* Expect a matching TRAP */
	function f_ctrl_exp_trap(IPA_CTRL_PT pt, template CtrlVariable variable,
				 template CtrlValue val := ?, float timeout_val := 2.0)
	return CtrlValue {
		timer T := timeout_val;
		var CtrlMessage rx;
		T.start;
		alt {
		[] pt.receive(tr_CtrlMsgTrap(variable, val)) -> value rx {
			}
		[] T.timeout {
			setverdict(fail, "Timeout waiting for TRAP ", variable);
			mtc.stop;
			}
		}
		return rx.trap.val;
	}

	/* Expect a matching SET, optionally answer */
	function f_ctrl_exp_set(IPA_CTRL_PT pt, template CtrlVariable variable,
				 template CtrlValue val := ?,
				 template (omit) CtrlValue rsp := omit,
				 float timeout_val := 2.0)
	return CtrlValue {
		timer T := timeout_val;
		var CtrlMessage rx;
		T.start;
		alt {
		[] pt.receive(tr_CtrlMsgSet(?, variable, val)) -> value rx {
			if (ispresent(rsp)) {
				pt.send(ts_CtrlMsgSetRepl(rx.cmd.id, valueof(variable), valueof(rsp)));
			}
			}
		[] T.timeout {
			setverdict(fail, "Timeout waiting for SET ", variable);
			mtc.stop;
			}
		}
		return rx.cmd.val;
	}

	/* Expect a matching GET result */
	function f_ctrl_get_exp(IPA_CTRL_PT pt, CtrlVariable variable, template CtrlValue exp) {
		var charstring ctrl_resp;
		ctrl_resp := f_ctrl_get(pt, variable);
		if (not match(ctrl_resp, exp)) {
			setverdict(fail, "Unexpected " & variable & ":" & ctrl_resp);
			mtc.stop;
		}
	}

	template charstring ts_ctrl_ratectr(CtrlVariable grp, integer instance, CtrlVariable name,
					    CtrlVariable kind := "abs") :=
		"rate_ctr." & kind & "." & grp & "." & int2str(instance) & "." & name;

	function f_ctrl_get_ratectr_abs(IPA_CTRL_PT pt, CtrlVariable grp, integer instance,
					CtrlVariable name) return integer {
		return str2int(f_ctrl_get(pt, valueof(ts_ctrl_ratectr(grp, instance, name))));
	}

	function f_ctrl_get_exp_ratectr_abs(IPA_CTRL_PT pt, CtrlVariable grp, integer instance,
					    CtrlVariable name, template integer exp) {
		var charstring ctrl_resp;
		var CtrlVariable variable := valueof(ts_ctrl_ratectr(grp, instance, name));
		ctrl_resp := f_ctrl_get(pt, variable);
		if (not match(str2int(ctrl_resp), exp)) {
			setverdict(fail, variable & " value " & ctrl_resp & " didn't match ", exp);
			mtc.stop;
		}
	}


	/* --- Retrieve and verify rate counter values in bulk ---
	 *
	 * BSC_Tests.ttcn shows a nice way to conveniently shorten the code needed to use these functions, see
	 * f_ctrs_msc_init() and f_ctrs_msc_expect().
	 *
	 * Here also a full usage example:
	 *
	 * const CounterNameVals my_counternames := {
	 *         { "mscpool:subscr:new", 0 },
	 *         { "mscpool:subscr:known", 0 },
	 *         { "mscpool:subscr:attach_lost", 0 },
	 * };
	 *
	 * var CounterNameValsList my_counters := f_counter_name_vals_get_n(instance_name := "msc", instance_count := 3,
	 *                                                                  counternames := my_counternames);
	 *
	 * // run some tests that increment rate counters in the program,
	 * // and increment expected counters accordingly:
	 * f_counter_name_vals_list_add(my_counters, instance_nr := 1, "mscpool:subscr:new", 7);
	 * f_counter_name_vals_list_add(my_counters, instance_nr := 2, "mscpool:subscr:attach_lost", 3);
	 *
	 * // verify that the program reflects the expected counters:
	 * f_counter_name_vals_expect_n(instance_name := "msc", my_counters);
	 *
	 * // run some more tests...
	 * f_counter_name_vals_list_add(my_counters, instance_nr := 0, "mscpool:subscr:known");
	 * // and verify again
	 * f_counter_name_vals_expect_n(instance_name := "msc", my_counters);
	 */

	/* One counter value, e.g. { "name", 23 } */
	type record CounterNameVal {
		charstring name,
		integer val
	}

	/* List of one instance's counters,
	 * e.g. { {"foo",23}, {"bar",42} }
	 */
	type record of CounterNameVal CounterNameVals;

	/* List of numerous instances' counters,
	 * e.g. { { {"foo",23}, {"bar",42} },
	 *        { {"foo",23}, {"bar",42} } }
	 */
	type record of CounterNameVals CounterNameValsList;

	/* Retrieve one instance's rate counter values of the given names. */
	function f_counter_name_vals_get(IPA_CTRL_PT pt, charstring instance_name, integer instance_nr,
					 CounterNameVals counternames)
	return CounterNameVals {
		var CounterNameVals vals;
		for (var integer i := 0; i < lengthof(counternames); i := i + 1) {
			vals[i] := {
				name := counternames[i].name,
				val := f_ctrl_get_ratectr_abs(pt, instance_name, instance_nr, counternames[i].name)
			};
		}
		return vals;
	}

	/* Retrieve the first N instances' rate counter values of the given names */
	function f_counter_name_vals_get_n(IPA_CTRL_PT pt, charstring instance_name := "msc",
					   integer instance_count, CounterNameVals counternames)
	return CounterNameValsList {
		var CounterNameValsList valslist;
		for (var integer instance_nr := 0; instance_nr < instance_count; instance_nr := instance_nr + 1) {
			valslist[instance_nr] := f_counter_name_vals_get(pt, instance_name, instance_nr, counternames);
		}
		log("retrieved rate counters: ", instance_name, ": ", valslist);
		return valslist;
	}

	/* In a list of one instance's counters, increment a specifically named counter. */
	function f_counter_name_vals_add(inout CounterNameVals vals, charstring countername, integer val := 1)
	{
		for (var integer i := 0; i < lengthof(vals); i := i + 1) {
			if (vals[i].name == countername) {
				vals[i].val := vals[i].val + val;
				return;
			}
		}
		/* name not found, append */
		vals[lengthof(vals)] := {
			name := countername,
			val := val
		}
	}

	/* In a list of several instances' counters, increment a specific instance's specifically named counter. */
	function f_counter_name_vals_list_add(inout CounterNameValsList vals, integer instance_nr,
	                                      charstring countername, integer val := 1)
	{
		f_counter_name_vals_add(vals[instance_nr], countername, val);
	}

	/* For a specific instance, call f_counter_name_vals_get() and compare with expected counter values.
	 * Set the test verdict accordingly. */
	function f_counter_name_vals_expect(IPA_CTRL_PT pt, charstring instance_name, integer instance_nr,
					    CounterNameVals vals) {
		var CounterNameVals now := f_counter_name_vals_get(pt, instance_name, instance_nr, vals);
		for (var integer i := 0; i < lengthof(vals); i := i + 1) {
			if (now[i].name != vals[i].name) {
				setverdict(fail, "Internal error");
			}
			if (now[i].val != vals[i].val) {
				setverdict(fail, "Rate counter mismatch: ", instance_name, " ", instance_nr,
					   " ", vals[i].name, " is at ", now[i].val, " but expected ", vals[i].val);
			}
		}
		setverdict(pass);
	}

	/* For N instances, call f_counter_name_vals_get() and compare with expected counter values.
	 * Set the test verdict accordingly. The number of instances is given by lengthof(valslist). */
	function f_counter_name_vals_expect_n(IPA_CTRL_PT pt, charstring instance_name, CounterNameValsList valslist) {
		for (var integer instance_nr := 0; instance_nr < lengthof(valslist); instance_nr := instance_nr + 1) {
			f_counter_name_vals_expect(pt, instance_name, instance_nr, valslist[instance_nr]);
		}
	}

}