add a piano app

userspace/extra/piano.c

@@ -0,0 +1,73 @@
+/* This file is part of ToaruOS and is released under the terms
+ * of the NCSA / University of Illinois License - see LICENSE.md
+ * Copyright (C) 2014 Kevin Lange
+ */
+#include <stdio.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/ioctl.h>
+#include <termios.h>
+
+int spkr = 0;
+
+struct spkr {
+	int length;
+	int frequency;
+};
+
+void note(int length, int frequency) {
+	struct spkr s = {
+		.length = 2,
+		.frequency = frequency,
+	};
+
+	write(spkr, &s, sizeof(s));
+}
+
+struct termios old;
+
+void set_unbuffered() {
+	tcgetattr(fileno(stdin), &old);
+	struct termios new = old;
+	new.c_lflag &= (~ICANON & ~ECHO);
+	tcsetattr(fileno(stdin), TCSAFLUSH, &new);
+}
+
+
+int main(int argc, char * argv[]) {
+
+	spkr = open("/dev/spkr", O_WRONLY);
+	if (spkr == -1) {
+		fprintf(stderr, "%s: could not open speaker\n", argv[0]);
+	}
+
+	set_unbuffered();
+
+	char c;
+	while (c = fgetc(stdin)) {
+		switch (c) {
+			case 'z': return 0;
+			case 'a': note(10, 1308); break;
+			case 'w': note(10, 1386); break;
+			case 's': note(10, 1468); break;
+			case 'e': note(10, 1556); break;
+			case 'd': note(10, 1648); break;
+			case 'f': note(10, 1746); break;
+			case 't': note(10, 1850); break;
+			case 'g': note(10, 1960); break;
+			case 'y': note(10, 2077); break;
+			case 'h': note(10, 2200); break;
+			case 'u': note(10, 2331); break;
+			case 'j': note(10, 2469); break;
+			case 'k': note(10, 2616); break;
+			case 'o': note(10, 2772); break;
+			case 'l': note(10, 2937); break;
+			case 'p': note(10, 3111); break;
+			case ';': note(10, 3296); break;
+			case '\'': note(10, 3492);break;
+		}
+	}
+
+	return 0;
+}
+