tweaks: avoid using strlen() where it is not needed

src/global.c

@@ -492,16 +492,16 @@ int keycode_from_string(const char *keystring)
 		if (strcasecmp(keystring, "^H") == 0)
 			return KEY_BACKSPACE;
 #endif
-		if (keystring[1] == '/' && strlen(keystring) == 2)
+		if (keystring[1] == '/' && keystring[2] == '\0')
 			return 31;
-		if (keystring[1] <= '_' && strlen(keystring) == 2)
+		if (keystring[1] <= '_' && keystring[2] == '\0')
 			return keystring[1] - 64;
 		else
 			return -1;
 	} else if (keystring[0] == 'M') {
 		if (strcasecmp(keystring, "M-Space") == 0)
 			return (int)' ';
-		if (keystring[1] == '-' && strlen(keystring) == 3)
+		if (keystring[1] == '-' && keystring[3] == '\0')
 			return tolower((unsigned char)keystring[2]);
 		else
 			return -1;

src/rcfile.c

@@ -419,7 +419,7 @@ void parse_binding(char *ptr, bool dobind)
 	ptr = parse_next_word(ptr);
 	keycopy = copy_of(keyptr);
 
-	if (strlen(keycopy) < 2) {
+	if (keycopy[1] == '\0') {
 		jot_error(N_("Key name is too short"));
 		goto free_things;
 	}
@@ -428,7 +428,7 @@ void parse_binding(char *ptr, bool dobind)
 	keycopy[0] = toupper((unsigned char)keycopy[0]);
 	keycopy[1] = toupper((unsigned char)keycopy[1]);
 	if (keycopy[0] == 'M' && keycopy[1] == '-') {
-		if (strlen(keycopy) > 2)
+		if (keycopy[2] != '\0')
 			keycopy[2] = toupper((unsigned char)keycopy[2]);
 		else {
 			jot_error(N_("Key name is too short"));