From ac9c23d35c69e2839d3864d4c106962a24796092 Mon Sep 17 00:00:00 2001
From: Zack Buhman <zack@buhman.org>
Date: Mon, 25 May 2020 19:36:04 -0700
Subject: [PATCH] base80: abandoned

---
 base80.c | 123 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 123 insertions(+)
 create mode 100644 base80.c

diff --git a/base80.c b/base80.c
new file mode 100644
index 0000000..bbc6f23
--- /dev/null
+++ b/base80.c
@@ -0,0 +1,123 @@
+#include <openssl/bn.h>
+#include <assert.h>
+#include <stdio.h>
+#include <string.h>
+
+
+uint8_t base80_symbols[80] =
+  "!$&()*+,-./0123456789:=?@ABCDEFGHIJKLMNOPQRSTUVWXYZ_abcdefghijklmnopqrstuvwxyz|~";
+
+#define INVALID_SYMBOL 255
+
+uint8_t symbols_base80[256] = {
+  [0 ... 255] = INVALID_SYMBOL,
+  ['!'] = 0,  ['$'] = 1,  ['&'] = 2,  ['('] = 3,  [')'] = 4,  ['*'] = 5,  ['+'] = 6,  [','] = 7,
+  ['-'] = 8,  ['.'] = 9,  ['/'] = 10, ['0'] = 11, ['1'] = 12, ['2'] = 13, ['3'] = 14, ['4'] = 15,
+  ['5'] = 16, ['6'] = 17, ['7'] = 18, ['8'] = 19, ['9'] = 20, [':'] = 21, ['='] = 22, ['?'] = 23,
+  ['@'] = 24, ['A'] = 25, ['B'] = 26, ['C'] = 27, ['D'] = 28, ['E'] = 29, ['F'] = 30, ['G'] = 31,
+  ['H'] = 32, ['I'] = 33, ['J'] = 34, ['K'] = 35, ['L'] = 36, ['M'] = 37, ['N'] = 38, ['O'] = 39,
+  ['P'] = 40, ['Q'] = 41, ['R'] = 42, ['S'] = 43, ['T'] = 44, ['U'] = 45, ['V'] = 46, ['W'] = 47,
+  ['X'] = 48, ['Y'] = 49, ['Z'] = 50, ['_'] = 51, ['a'] = 52, ['b'] = 53, ['c'] = 54, ['d'] = 55,
+  ['e'] = 56, ['f'] = 57, ['g'] = 58, ['h'] = 59, ['i'] = 60, ['j'] = 61, ['k'] = 62, ['l'] = 63,
+  ['m'] = 64, ['n'] = 65, ['o'] = 66, ['p'] = 67, ['q'] = 68, ['r'] = 69, ['s'] = 70, ['t'] = 71,
+  ['u'] = 72, ['v'] = 73, ['w'] = 74, ['x'] = 75, ['y'] = 76, ['z'] = 77, ['|'] = 78, ['~'] = 79,
+};
+
+int main2(void);
+
+int
+main(void)
+{
+  int ret;
+  BN_CTX *ctx = BN_CTX_new();
+  BIGNUM *num = BN_new();
+  const BIGNUM *zero = BN_new();
+  BIGNUM *remainder = BN_new();
+  BIGNUM *div80 = BN_new();
+  BIGNUM *quot = BN_new();
+  BIGNUM *temp;
+
+  BN_set_word(div80, 80);
+
+  //char c[] = "The BN library performs arithmet";
+  char c[] = "performs arithmet";
+  char buf[32] = {0};
+
+  memcpy(buf + 32 - (sizeof (c)) - 1, c, (sizeof (c)) - 1);
+
+
+  BN_bin2bn(buf, (sizeof (buf)), num);
+
+  char *dec = BN_bn2dec(num);
+  printf("%s\n", dec);
+  free(dec);
+
+  int index = 0;
+  char out[42] = {0};
+
+  while (BN_cmp(num, zero) == 1) {
+    //int BN_div(BIGNUM *dv, BIGNUM *rem, const BIGNUM *a, const BIGNUM *d, BN_CTX *ctx);
+    assert(BN_div(quot, remainder, num, div80, ctx));
+    BN_ULONG w = BN_get_word(remainder);
+
+    char *dec = BN_bn2dec(quot);
+    printf("%s %ld\n", dec, w);
+    free(dec);
+
+    assert(80 > w);
+    out[index] = base80_symbols[w];
+    index++;
+
+    temp = quot;
+    quot = num;
+    num = temp;
+  }
+
+  printf("%s\n", out);
+
+  BN_clear_free(num);
+  BN_free((BIGNUM*)zero);
+  BN_clear_free(div80);
+  BN_clear_free(remainder);
+  BN_CTX_free(ctx);
+
+  main2();
+
+  return 0;
+
+}
+
+int
+main2(void)
+{
+  //char buf[] = "qtt|Mlp&ruG@(BWyr:u+eWssG,$YxIsVHp)r1Gkr&";
+  char buf[] = "U9ZegR,E*B2m@VoRcGH";
+  uint8_t w;
+
+  char out[33] = {0};
+
+  BIGNUM *num = BN_new();
+  BIGNUM *mul80 = BN_new();
+  BN_CTX *ctx = BN_CTX_new();
+
+  BN_set_word(mul80, 80);
+
+  int index = (sizeof (buf)) - 1;
+
+  while (index > 0) {
+    w = symbols_base80[buf[--index]];
+    assert(w != INVALID_SYMBOL);
+    BN_mul(num, num, mul80, ctx);
+    BN_add_word(num, w);
+    char *dec = BN_bn2dec(num);
+    printf("%s %d\n", dec, w);
+    free(dec);
+  }
+
+  printf("%d\n", BN_num_bytes(num));
+  assert((sizeof (out)) - 1 >= BN_num_bytes(num));
+  BN_bn2bin(num, out);
+  printf("%s\n", out);
+
+  return 0;
+}