commit: ad8f35c554aae372eb50a66b67e0010fb83dae72
parent 5b02f8a04f935c85c84f0651aa54cea59494d632
Author: Haelwenn (lanodan) Monnier <contact@hacktivis.me>
Date: Sun, 31 Oct 2021 00:41:57 +0200
C/tap_code: New, based on morse.c
Diffstat:
| A | C/tap_code.c | 127 | +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ |
1 file changed, 127 insertions(+), 0 deletions(-)
diff --git a/C/tap_code.c b/C/tap_code.c
@@ -0,0 +1,127 @@
+// echo 'hello world' | ./tap_code | $PLAYER -
+// $PLAYER: Any au(5) aware audio player (sox's play(1), mpv, …)
+// https://en.wikipedia.org/wiki/Tap_code
+#define _POSIX_C_SOURCE 200809L
+#include "au.h"
+
+#include <inttypes.h> // uint32_t
+#include <stdio.h> // getchar(), putchar(), fputs()
+
+// Fuckings to GNU; Love to musl libc
+// https://drewdevault.com/2020/09/25/A-story-of-two-libcs.html
+int
+isalpha(int c)
+{
+ return ((unsigned)c | 32) - 'a' < 26;
+}
+
+int
+toupper(int c)
+{
+ // 'A' - 'a' = -32
+ return c - 32;
+}
+
+int dur = 8000 / 25; // time unit length
+int t = 0;
+
+// 'Z' = 0d90
+static int tap_code[26][2] = {
+ {1, 1}, // A
+ {1, 2}, // B
+ {1, 3}, // C
+ {1, 4}, // D
+ {1, 5}, // E
+ {2, 1}, // F
+ {2, 2}, // G
+ {2, 3}, // H
+ {2, 4}, // I
+ {2, 5}, // J
+ {1, 3}, // K = C
+ {3, 1}, // L
+ {3, 2}, // M
+ {3, 3}, // N
+ {3, 4}, // O
+ {3, 5}, // P
+ {4, 1}, // Q
+ {4, 2}, // R
+ {4, 3}, // S
+ {4, 4}, // T
+ {4, 5}, // U
+ {5, 1}, // V
+ {5, 2}, // W
+ {5, 3}, // X
+ {5, 4}, // Y
+ {5, 5}, // Z
+};
+
+void
+code_to_tap(int code)
+{
+ for(int d = 0; d < code; d++)
+ {
+ for(int i = 0; i < dur; i++, t++)
+ {
+ putchar(t++ * 1 % 30);
+ }
+
+ for(int i = 0; i < dur * 2; i++, t++)
+ {
+ putchar(t++ * 0 % 30);
+ }
+ }
+
+ for(int i = 0; i < dur * 4; i++, t++)
+ {
+ putchar(t++ * 0 % 30);
+ }
+}
+
+int
+main(void)
+{
+ // Use AU defaults
+ struct au_header header = {.offset = 24, // no-annotation, in octets
+ .length = 0xFFFFFFFF, // unknown data size
+ .encoding = AU_ENCODING_8B_LPCM,
+ .samplerate = 8000, // Hz
+ .channels = 1};
+
+ // fd 1 is stdout
+ write_au_header(1, &header);
+
+ fputs("ASCII text in, raw audio out", stderr);
+
+ int c = 0;
+ while((c = getchar()) != -1)
+ {
+ if(isalpha(c))
+ {
+ if(c >= 'a' && c <= 'z')
+ {
+ c = c - 'a';
+ }
+ else if(c >= 'A' && c <= 'Z')
+ {
+ c = c - 'A';
+ }
+
+ code_to_tap(tap_code[c][0]);
+ code_to_tap(tap_code[c][1]);
+ }
+ else
+ {
+ for(int i = 0; i < dur; i++, t++)
+ {
+ putchar(t++ * 2 % 30);
+ }
+ }
+
+ for(int i = 0; i < dur * 8; i++, t++)
+ {
+ putchar(t++ * 0 % 30);
+ }
+ }
+
+ return 0;
+}
