network coords parsing

uttt.c

@@ -188,19 +188,78 @@ bool getpos(const struct ut_state *state, int *x, int *y) {
 	return true;
 }
 
-void getpos_net(const struct ut_state *state, int conn, int *x, int *y) {
-	char buf[4];
-	int n = recv(conn, &buf, 4, 0); // lazy way but idc
-	printf("bytes received: %d\n", n);
-	printf("buf=%s\n", buf);
-	*x = buf[0] - 0x30;
-	*y = buf[2] - 0x30;
-	printf("x=%d y=%d\n", *x, *y);
-	if (buf[1] != ',' || buf[3] != '\n' || *x >= 9 || *y >= 9 || *x < 0 || *y < 0) {
-		printf("protocol not followed perfectly by partner - exiting\n");
-		close(conn);
-		exit(1);
+void getpos_net(const struct ut_state *state, int conn, FILE* conn_file, int *x, int *y) {
+	const int MAX_LINE_LEN = 120;
+	char byte;
+	int n;
+	while (true) {
+		n = recv(conn, &byte, 1, 0);
+		if (n == 0) {goto conn_closed;}
+		if (byte == '|') {
+			// ignore this line
+			for (int i = 0; i < MAX_LINE_LEN; i++) {
+				n = recv(conn, &byte, 1, 0);
+				if (n == 0) {goto conn_closed;}
+				if (byte == '\n') {break;}
+			}
+			if (byte != '\n') {
+				printf("Partner sent too much data in one comment line - exiting\n");
+				close(conn);
+				exit(1);
+			}
+		} else {
+			if (byte == '\n') {
+				printf("Partner ended line before coords were complete - retrying\n");
+				fprintf(conn_file, "Invalid coordinates. Try again: ");
+				fflush(conn_file);
+				continue;
+			}
+			*x = byte - 0x30;
+			n = recv(conn, &byte, 1, 0);
+			if (n == 0) {goto conn_closed;}
+			if (byte == '\n') {
+				printf("Partner ended line before coords were complete - retrying\n");
+				fprintf(conn_file, "Invalid coordinates. Try again: ");
+				fflush(conn_file);
+				continue;
+			}
+			n = recv(conn, &byte, 1, 0);
+			if (n == 0) {goto conn_closed;}
+			if (byte == '\n') {
+				printf("Partner ended line before coords were complete - retrying\n");
+				fprintf(conn_file, "Invalid coordinates. Try again: ");
+				fflush(conn_file);
+				continue;
+			}
+			*y = byte - 0x30;
+			n = recv(conn, &byte, 1, 0);
+			if (n == 0) {goto conn_closed;}
+			if (byte != '\n') {
+				printf("Partner sent extra data after coords were complete - ignoring and retrying\n");
+				fprintf(conn_file, "Invalid coordinates. Try again: ");
+				fflush(conn_file);
+				// ignore the rest of this line
+				for (int i = 0; i < MAX_LINE_LEN; i++) {
+					n = recv(conn, &byte, 1, 0);
+					if (n == 0) {goto conn_closed;}
+					if (byte == '\n') {break;}
+				}
+				if (byte != '\n') {
+					printf("Partner sent too much extra data - exiting\n");
+					close(conn);
+					exit(1);
+				}
+				continue;
+			}
+			break;
+		}
 	}
+	printf("x=%d y=%d\n", *x, *y);
+	return;
+
+	conn_closed:
+	printf("Connection closed.\n");
+	exit(1);
 }
 
 void finish(int sig)
@@ -252,7 +311,7 @@ void ut_host_game(struct ut_state *state, int conn, char host_player) {
 			printf("Waiting for game partner ...\n");
 			fprintf(conn_file, "Place token %c in position x,y: ", ut_turn(host_player));
 			fflush(conn_file);
-			getpos_net(state, conn, &x, &y);
+			getpos_net(state, conn, conn_file, &x, &y);
 		}
 		int err = ut_move(state, state, y, x);
 		if (err) {continue;}