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/* This file is part of the Zebra server.
Copyright (C) Index Data
Zebra is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 2, or (at your option) any later
version.
Zebra is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#if HAVE_CONFIG_H
#include <config.h>
#endif
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <assert.h>
#include <yaz/xmalloc.h>
#include <su_codec.h>
int key_SU_encode (int ch, char *out)
{
int i;
if (ch == -1)
{
/* unique value .. which is different from ch >= 0 case */
/* is used to generate queries with "null" hits, bug #1142 */
out[0] = 129;
return 1;
}
for (i = 0; ch; i++)
{
if (ch >= 64)
out[i] = 65 + (ch & 63);
else
out[i] = 1 + ch;
ch = ch >> 6;
}
return i;
/* in out
0 1
1 2
63 64
64 65, 2
65 66, 2
127 128, 2
128 65, 3
191 128, 3
192 65, 4
*/
}
int key_SU_decode (int *ch, const unsigned char *out)
{
int len = 1;
int fact = 1;
*ch = 0;
for (len = 1; *out >= 65; len++, out++)
{
*ch += (*out - 65) * fact;
fact <<= 6;
}
*ch += (*out - 1) * fact;
return len;
}
/*
* Local variables:
* c-basic-offset: 4
* c-file-style: "Stroustrup"
* indent-tabs-mode: nil
* End:
* vim: shiftwidth=4 tabstop=8 expandtab
*/
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