Store UCI strings in progmem

ArduChess.ino

@@ -177,8 +177,8 @@ void setup() {
 	board_init();
 	Serial.begin(115200);
 	pinMode(LED_BUILTIN, OUTPUT);
-	perft_test();
-	bench();
+	//perft_test();
+	//bench();
 }
 
 void loop() {

Uci.h

@@ -1,11 +1,13 @@
 #ifndef __UCI_H_INC
 #define __UCI_H_INC
 
+#define PS2(s) ([]{ static const char c[] PROGMEM = (s); return &c[0]; }())
+
 typedef void uci_return;
 typedef uci_return (*uci_handler)();
 
 struct uci_cmd {
-	char* command;
+	const char* command;
 	uci_handler handler;
 };
 
@@ -22,27 +24,28 @@ uci_return uci_unknown() {
 }
 
 const uci_cmd UCI_COMMANDS[] = {
-	{"uci", &uci_hello},
-	{"debug", &uci_unimpl},
-	{"isready", &uci_unimpl},
-	{"setoption", &uci_unimpl},
-	{"ucinewgame", &uci_unimpl},
-	{"position", &uci_unimpl},
-	{"go", &uci_unimpl},
-	{"stop", &uci_unimpl},
-	{"ponderhit", &uci_unimpl},
-	{"quit", &uci_unimpl},
+	{PS2("uci"), &uci_hello},
+	{PS2("debug"), &uci_unimpl},
+	{PS2("isready"), &uci_unimpl},
+	{PS2("setoption"), &uci_unimpl},
+	{PS2("ucinewgame"), &uci_unimpl},
+	{PS2("position"), &uci_unimpl},
+	{PS2("go"), &uci_unimpl},
+	{PS2("stop"), &uci_unimpl},
+	{PS2("ponderhit"), &uci_unimpl},
+	{PS2("quit"), &uci_unimpl},
 };
 
-const uci_cmd UCI_INVALID = {"", &uci_unknown};
+const uci_cmd UCI_INVALID = {PS2(""), &uci_unknown};
 
-uci_cmd get_uci_command(char* command) {
+uci_cmd get_uci_command(const char* command) {
 	size_t command_num = sizeof(UCI_COMMANDS) / sizeof(uci_cmd);
-	for(int i = 0; i < command_num; i++) {
-		int ci = 0;
+	for(size_t i = 0; i < command_num; i++) {
+		size_t ci = 0;
 		uci_cmd to_try = UCI_COMMANDS[i];
 		while(true) {
-			if(to_try.command[ci] != command[ci]) {
+			char reference = pgm_read_byte_near(to_try.command + ci);
+			if(reference != command[ci]) {
 				break;
 			}
 			if(command[ci] == '\0') {