refactor server/client discovery to use TLVs.

Signed-off-by: Gediminas Jakutis <gediminas@varciai.lt>

3 files changed, 66 insertions, 31 deletions

diff --git a/src/device/device_network.cpp b/src/device/device_network.cpp
index f2456d9..1810852 100644
--- a/src/device/device_network.cpp
+++ b/src/device/device_network.cpp
@@ -22,7 +22,8 @@
 #include <ESP8266WiFi.h>
 #include <WiFiUdp.h>
 #include "device_network.h"
-#include "net.h"
+#include "utils.h"
+#include "tlv.h"
 
 static struct netstate {
 	WiFiUDP udp;
@@ -73,17 +74,31 @@ size_t udp_get_data(char *buf, size_t size)
 void discover_client(const int port)
 {
 	IPAddress bcastip(255, 255, 255, 255);
-	char buffer[32] = {0};
+	char buffer[128] = {0};
+	struct tlv field;
+	struct tlv_packet pack;
+	size_t expected_s;
+
+	tlv_init(&field, HEARTBEAT);
+	field.data = strdup(heartbeat_device);
+	field.head.size = sizeof(heartbeat_device);
+	tlv_packet_init(&pack);
+	tlv_pack(&pack, &field);
+	tlv_packet_finalize(&pack);
+	tlv_destroy(&field);
 
 	do {
 		udp_init_packet_expaddr(bcastip, port);
-		udp_push(servermagic, sizeof(servermagic));
+		udp_push(pack.data, pack.cursor + 1);
 		udp_flush();
 		delay(5);
+
+		expected_s = sizeof(field.head) + sizeof(heartbeat_server);
 		while (state.udp.parsePacket()) {
-			if (state.udp.available() >= sizeof(clientmagic)) {
-				state.udp.read(buffer, sizeof(clientmagic));
-				if (!(strcmp(clientmagic, buffer))) {
+			if (state.udp.available() >= expected_s) {
+				state.udp.read(buffer, sizeof(buffer));
+				tlv_get(buffer, &field, NULL);
+				if (field.head.type == HEARTBEAT && !(strcmp(heartbeat_server, field.data))) {
 					state.daemon_ip = state.udp.remoteIP();
 					++state.acquired;
 				}
@@ -91,6 +106,8 @@ void discover_client(const int port)
 		}
 		delay(95);
 	} while (!state.acquired);
+
+	tlv_packet_destroy(&pack);
 }
 
 IPAddress *get_daemon_address(void)
diff --git a/src/device/device_network.h b/src/device/device_network.h
index 92af429..ae719f0 100644
--- a/src/device/device_network.h
+++ b/src/device/device_network.h
@@ -35,7 +35,4 @@ size_t udp_get_data(char *buf, size_t size);
 void discover_client(const int port);
 IPAddress *get_daemon_address(void);
 
-static const char servermagic[] = "I love coffee!";
-static const char clientmagic[] = "I love tea!";
-
 #endif /* DEVICE_UDP_H */
diff --git a/src/device/main.ino b/src/device/main.ino
index 4376346..0835906 100644
--- a/src/device/main.ino
+++ b/src/device/main.ino
@@ -28,7 +28,7 @@
 #include "DejaVu_Sans_Mono_13.h"
 #include "device_network.h"
 #include "screen.h"
-#include "net.h"
+#include "utils.h"
 #include "tlv.h"
 
 static const unsigned int internal_led = 2;
@@ -42,20 +42,22 @@ static void blink_led(const int pin, const int ontime, const int offtime);
 void handle_tlv(const struct tlv *data);
 
 static struct progstate_t {
-	int ip_print_count = 5;
-	struct display_status ds = {0};
-	struct tlv_parser parser = {0};
-	struct tlv crr_data;
-	size_t bytes_read = 0;
-	char in_packet_buf[MTU];
+	int ip_print_count;
+	struct display_status ds;
+	struct tlv field;
+	struct tlv_packet heartbeat;
+	size_t bytes_read;
+	char buf[MTU];
+	char hbcounter;
 } progstate;
 
 void setup(void)
 {
 	extern const char * const ssid;
 	extern const char * const password;
-	pinMode(internal_led, OUTPUT);
+	struct tlv field;
 
+	pinMode(internal_led, OUTPUT);
 	toggle_led(internal_led);
 	init_OLED();
 	display.fillCircle(32, 16, 12);
@@ -67,9 +69,16 @@ void setup(void)
 	discover_client(com_port);
 	display.fillCircle(92, 16, 12);
 	display.display();
+	progstate.ip_print_count = 5;
+	tlv_init(&field, HEARTBEAT);
+	field.data = strdup(heartbeat_device);
+	field.head.size = sizeof(heartbeat_device);
+	tlv_packet_init(&progstate.heartbeat);
+	tlv_pack(&progstate.heartbeat, &field);
+	tlv_packet_finalize(&progstate.heartbeat);
+	tlv_destroy(&field);
 }
 
-/* the logic is a placeholder right now */
 void loop(void)
 {
 	static const String devstr = "Device IP:";
@@ -77,16 +86,22 @@ void loop(void)
 	static String prefix;
 	static IPAddress ip_to_print;
 	static IPAddress *daemon_ip = NULL;
+#if 0
+	char *saveptr;
+#endif
 
 	static unsigned int delta = 2000; /* sleep length to use (ms) */
 
 	delay(delta);
-	/* Initial display of ip's. */
-	if (progstate.ip_print_count > 0) {
+	if (!progstate.hbcounter) {
 		udp_init_packet(com_port);
-		udp_push(clientmagic, sizeof(clientmagic));
+		udp_push(progstate.heartbeat.data, progstate.heartbeat.cursor + 1);
 		udp_flush();
+		progstate.hbcounter = 2;
+	}
 
+	if (progstate.ip_print_count) {
+		/* Initial display of ip's. */
 		if (!daemon_ip) {
 			daemon_ip = get_daemon_address();
 		}
@@ -98,27 +113,33 @@ void loop(void)
 		display.drawString(0, 16, ip_to_print.toString());
 		display.display();
 		progstate.ip_print_count--;
-	} else {	/* Dealing with tlv's one at a time. */
-		progstate.bytes_read = udp_get_data(progstate.in_packet_buf, sizeof(progstate.in_packet_buf));
+	} else {
+		progstate.bytes_read = udp_get_data(progstate.buf, sizeof(progstate.buf));
 		if (progstate.bytes_read > 0) {
-			progstate.parser.data = progstate.in_packet_buf;
-			progstate.parser.offset = 0;
-			/* Ignore errors for now. */
-			while (tlv_get(&progstate.parser, &progstate.crr_data) == 0) {
-				handle_tlv(&progstate.crr_data);
+			tlv_get(progstate.buf, &progstate.field, NULL);
+			handle_tlv(&progstate.field);
+#if 0
+			/* Dealing with tlv's one at a time. */
+			saveptr = progstate.buf;
+			while (!(tlv_get(saveptr, &progstate.field, &saveptr))) {
+				handle_tlv(&progstate.field);
 			}
+#endif
 		}
+
 		display_update_scroll(&progstate.ds);
 	}
+
+	--progstate.hbcounter;
 }
 
-void handle_tlv(const struct tlv *t)
+void handle_tlv(const struct tlv *in)
 {
 	/* Currently just dealing with text.
 	 * */
-	switch (t->type) {
+	switch (in->head.type) {
 	case TEXT:
-		display_status_init(&display, &progstate.ds, (char *)t->data);
+		display_status_init(&display, &progstate.ds, in->data);
 		break;
 	default:
 		display.clear();