/*
 * ubase64.C: ircu base64 routines.
 * Rights to this code are documented in doc/pod/license.pod.
 *
 * Copyright © 2005-2007 Atheme Project (http://www.atheme.org)
 */

static char const rcsid[] = "$Id: ubase64.C,v 1.3 2007/07/21 13:23:22 pippijn Exp $";

#include "atheme.h"

/*
 * base64touint() written 01/20/06 by jilles, for getting IP addresses.
 */

static const char ub64_alphabet[65] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789[]";
#define __ '\377'
static const char ub64_lookuptab[256] = {
  __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __,	/* 0-15 */
  __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __,	/* 16-31 */
  __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __,	/* 32-47 */
  52, 53, 54, 55, 56, 57, 58, 59, 60, 61, __, __, __, __, __, __,	/* 48-63 */
  __, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14,	/* 64-79 */
  15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 62, __, 63, __, __,	/* 80-95 */
  __, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,	/* 96-111 */
  41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, __, __, __, __, __,	/* 112-127 */
  __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __,
  __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __,
  __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __,
  __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __,
  __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __,
  __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __,
  __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __,
  __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __
};

#undef __

const char *
uinttobase64 (char *buf, uint64_t v, int64_t count)
{
  buf[count] = '\0';

  while (count >= 0)
    {
      buf[--count] = ub64_alphabet[v & 63];
      v >>= 6;
    }

  return buf;
}

unsigned int
base64touint (char *buf)
{
  int bits;
  unsigned int v = 0;
  int count = 6;

  while (--count >= 0 && (bits = ub64_lookuptab[255 & *buf++]) != '\377')
    v = v << 6 | bits;
  return v;
}

/* vim:cinoptions=>s,e0,n0,f0,{0,}0,^0,=s,ps,t0,c3,+s,(2s,us,)20,*30,gs,hs
 * vim:ts=8
 * vim:sw=8
 * vim:noexpandtab
 */