morse: add program

Converts ASCII input to morse code

diff --git a/morse.c b/morse.c
new file mode 100644 (file)
index 0000000..27e0fa6
--- /dev/null
+++ b/morse.c
@@ -0,0 +1,56 @@
+/* Convert ASCII to morse code. Reads from stdin if provided with no argument
+        or "-", otherwise reads from the first command line argument. Prints "*" if
+        character is not found. */
+
+#include <string.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+const char *aa[] = {"a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l",
+       "m", "n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z", "1",
+       "2", "3", "4", "5", "6", "7", "8", "9", "0", " "};
+
+const char *ma[] = {"•-", "-•••", "-•-•", "-••", "•", "••-•", "--•", "••••",
+       "••", "•---", "-•-", "•-••", "--", "-•", "---", "•--•", "--•-", "•-•", "•••",
+       "-", "•--", "•••-", "•--", "-••-", "-•--", "--••", "•----", "••---", "•••--",
+       "••••-", "•••••", "-••••", "--•••", "---••", "----•", "-----", "   "};
+
+void
+convert(char *c)
+{
+       if (strcmp(c, "\n") == 0) {
+               printf("\n");
+               return;
+       }
+
+       for (int i = 0; aa[i]; i++) {
+               if (strcmp(c, aa[i]) == 0) {
+                       printf("%s", ma[i]);
+                       break;
+               } else if (i == sizeof(aa)/sizeof(char *) - 1) {
+                       printf("*");
+               }
+       }
+       printf(" ");
+}
+
+int
+main(int argc, char **argv)
+{
+       char c[2];
+       c[1] = '\0';
+
+       if (argv[1] && strcmp(argv[1], "-") != 0) {
+               for (int i = 0; argv[1][i]; i++) {
+                       c[0] = argv[1][i];
+                       convert(c);
+               }
+       } else {
+               while (read(STDIN_FILENO, &c[0], 1) > 0) {
+                       convert(c);
+               }
+       }
+       printf("\n");
+       return 0;
+}