From b6b5becf359370c7f32d8419bcf8f50a47fbe933 Mon Sep 17 00:00:00 2001
From: Moritz Röhrich <moritz@ildefons.de>
Date: Thu, 7 Jan 2021 17:40:20 +0100
Subject: new toy: base32

Add new toy `base32`. Add tests for `base32`.

base32 is added by adapting the base64 encode/decode function to also do
base32 encoding/decoding. Then their respective main functions set up
the global parameter `n` to be the number of bits used in the encoding
(5 for base32 and 6 for base64) and `align` to align the result to a
certain length via padding. These are deliberately kept as parameters to
enable future expansion for other bases easily.
---
 toys/other/base64.c | 46 +++++++++++++++++++++++++++++++++++++---------
 1 file changed, 37 insertions(+), 9 deletions(-)

(limited to 'toys/other')

diff --git a/toys/other/base64.c b/toys/other/base64.c
index ef7854a1..25e37d41 100644
--- a/toys/other/base64.c
+++ b/toys/other/base64.c
@@ -5,6 +5,7 @@
  * No standard
 
 USE_BASE64(NEWTOY(base64, "diw#<0=76[!dw]", TOYFLAG_USR|TOYFLAG_BIN))
+USE_BASE32(NEWTOY(base32, "diw#<0=76[!dw]", TOYFLAG_USR|TOYFLAG_BIN))
 
 config BASE64
   bool "base64"
@@ -14,6 +15,18 @@ config BASE64
 
     Encode or decode in base64.
 
+    -d	Decode
+    -i	Ignore non-alphabetic characters
+    -w	Wrap output at COLUMNS (default 76 or 0 for no wrap)
+
+config BASE32
+  bool "base32"
+  default y
+  help
+    usage: base32 [-di] [-w COLUMNS] [FILE...]
+
+    Encode or decode in base32.
+
     -d	Decode
     -i	Ignore non-alphabetic characters
     -w	Wrap output at COLUMNS (default 76 or 0 for no wrap)
@@ -24,8 +37,9 @@ config BASE64
 
 GLOBALS(
   long w;
-
   unsigned total;
+  unsigned n;  // number of bits used in encoding. 5 for base32, 6 for base64
+  unsigned align;  // number of bits to align to
 )
 
 static void wraputchar(int c, int *x)
@@ -38,7 +52,7 @@ static void wraputchar(int c, int *x)
   };
 }
 
-static void do_base64(int fd, char *name)
+static void do_base_n(int fd, char *name)
 {
   int out = 0, bits = 0, x = 0, i, len;
   char *buf = toybuf+128;
@@ -49,8 +63,8 @@ static void do_base64(int fd, char *name)
     // If no more data, flush buffer
     if (!(len = xread(fd, buf, sizeof(toybuf)-128))) {
       if (!FLAG(d)) {
-        if (bits) wraputchar(toybuf[out<<(6-bits)], &x);
-        while (TT.total&3) wraputchar('=', &x);
+        if (bits) wraputchar(toybuf[out<<(TT.n-bits)], &x);
+        while (TT.total&TT.align) wraputchar('=', &x);
         if (x) xputc('\n');
       }
 
@@ -62,8 +76,8 @@ static void do_base64(int fd, char *name)
         if (buf[i] == '=') return;
 
         if ((x = stridx(toybuf, buf[i])) != -1) {
-          out = (out<<6) + x;
-          bits += 6;
+          out = (out<<TT.n) + x;
+          bits += TT.n;
           if (bits >= 8) {
             putchar(out >> (bits -= 8));
             out &= (1<<bits)-1;
@@ -78,8 +92,8 @@ static void do_base64(int fd, char *name)
       } else {
         out = (out<<8) + buf[i];
         bits += 8;
-        while (bits >= 6) {
-          wraputchar(toybuf[out >> (bits -= 6)], &x);
+        while (bits >= TT.n) {
+          wraputchar(toybuf[out >> (bits -= TT.n)], &x);
           out &= (1<<bits)-1;
         }
       }
@@ -89,6 +103,20 @@ static void do_base64(int fd, char *name)
 
 void base64_main(void)
 {
+  TT.n = 6;
+  TT.align = 3;
   base64_init(toybuf);
-  loopfiles(toys.optargs, do_base64);
+  loopfiles(toys.optargs, do_base_n);
+}
+
+#define CLEANUP_base64
+#define FOR_base32
+#include "generated/flags.h"
+
+void base32_main(void)
+{
+  TT.n = 5;
+  TT.align = 7;
+  base32_init(toybuf);
+  loopfiles(toys.optargs, do_base_n);
 }
-- 
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