mobile: Add lua examples for basic functions that are available

Link to Lua docs, link to our manual. Demo logging, timer, MS
on/off, sms sending and sms receiving. For the MM state I will
need to export constants/names to make this usable. Currently
it is a bit of a hack (first time to MM_IDLE) to send a SMS. We
would know when we attached though.

Change-Id: I10ac656330b65e3905d6cbbb7865aa0f969cd9ff

doc/examples/mobile/lua_helloworld.lua

@@ -0,0 +1,9 @@
+-- See https://www.lua.org/manual/5.3/ for Lua
+-- See http://ftp.osmocom.org/docs/latest/osmocombb-usermanual.pdf -- Scripting with Lua
+
+-- Standard print and log_* are forwarded to the Osmocom logging framework
+print("Hellp from Lua");
+log_notice("Notice from lua");
+log_debug("Debug from Lua");
+log_error("Error from Lua");
+log_fatal("Fatal from Lua");

doc/examples/mobile/lua_ms_on_off.lua

@@ -0,0 +1,23 @@
+-- See https://www.lua.org/manual/5.3/ for Lua
+-- See http://ftp.osmocom.org/docs/latest/osmocombb-usermanual.pdf -- Scripting with Lua
+
+
+-- Switch the MS on/off but this can only be done if the MS
+-- is in the right state. This assumes that the MS is fully
+-- connected and doesn't stall.
+
+local start = false
+osmo.ms().start()
+function toggle_ms_state()
+	timer = osmo.timeout(20, function()
+		if start then
+			print("STARTING", osmo.ms().start())
+			start = false
+		else
+			print("STOPPING", osmo.ms().stop(true))
+			start = true
+		end
+		toggle_ms_state()
+	end)
+end
+toggle_ms_state()

doc/examples/mobile/lua_sms_on_attach.lua

@@ -0,0 +1,32 @@
+-- See https://www.lua.org/manual/5.3/ for Lua
+-- See http://ftp.osmocom.org/docs/latest/osmocombb-usermanual.pdf -- Scripting with Lua
+
+
+-- State change
+local sent_sms = false
+function mm_cb(new_state, new_substate, old_substate)
+	-- The system has attached and returned to idle. Send a SMS the first time
+	-- it happens.
+	if new_state == 19 and new_substate == 1 then
+		if not sent_sms then
+			sent_sms = true
+			osmo.ms():sms_send_simple("1234", "21321324", "fooooooo", 23)
+		end
+	end
+end
+
+-- Called when a new SMS arrives or status for delivery
+-- is updated. Check the msg_ref field.
+function sms_cb(sms, cause, valid)
+	print("SMS data cb", sms, cause, valid)
+	for i, v in pairs(sms) do
+		print(i, v)
+	end
+end
+
+-- We need to register a callback 
+local cbs = {
+	Sms=sms_cb,
+	Mm=mm_cb
+}
+osmo.ms():register(cbs)

doc/examples/mobile/lua_sms_receive.lua

@@ -0,0 +1,15 @@
+-- See https://www.lua.org/manual/5.3/ for Lua
+-- See http://ftp.osmocom.org/docs/latest/osmocombb-usermanual.pdf -- Scripting with Lua
+
+function sms_cb(sms, cause, valid)
+	print("SMS data cb", sms, cause, valid)
+	for i, v in pairs(sms) do
+		print(i, v)
+	end
+end
+
+local cbs = {
+	Sms=sms_cb,
+}
+
+osmo.ms():register(cbs)

doc/examples/mobile/lua_timer.lua

@@ -0,0 +1,12 @@
+-- See https://www.lua.org/manual/5.3/ for Lua
+-- See http://ftp.osmocom.org/docs/latest/osmocombb-usermanual.pdf -- Scripting with Lua
+
+-- Start and stop timer with callback. Schedule a timeout and
+-- resume execution then.
+
+-- Timeout in 10 seconds
+local timer = osmo.timeout(10, function()
+	print("Timeout occurred");
+end)
+-- We can cancel it. The callback will not be called
+timer:cancel()