freeswitch/libs/sofia-sip/libsofia-sip-ua/msg/sofia-sip/msg_mclass_hash.h

78 lines
1.8 KiB
C

/*
* This file is part of the Sofia-SIP package
*
* Copyright (C) 2005 Nokia Corporation.
*
* Contact: Pekka Pessi <pekka.pessi@nokia.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public License
* as published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA
*
*/
#ifndef MSG_MCLASS_HASH_H
/** Defined when <sofia-sip/msg_mclass_hash.h> has been included. */
#define MSG_MCLASS_HASH_H
/**@ingroup msg_parser
* @file sofia-sip/msg_mclass_hash.h
*
* Hash function for header names.
*
* @author Pekka Pessi <Pekka.Pessi@nokia.com>
*
* @date Created: Tue Aug 21 16:03:45 2001 ppessi
*
*/
#include <sofia-sip/su_config.h>
#ifndef BNF_H
#include <sofia-sip/bnf.h>
#endif
SOFIA_BEGIN_DECLS
/** Hash the header name */
#define MC_HASH(s, n) (msg_header_name_hash(s, NULL) % (unsigned)(n))
/** Hash header name */
su_inline
unsigned short msg_header_name_hash(char const *s, isize_t *llen)
{
unsigned short hash = 0;
size_t i;
for (i = 0; s[i]; i++) {
unsigned char c = s[i];
if (!(_bnf_table[c] & bnf_token))
break;
if (c >= 'A' && c <= 'Z')
hash += (c + 'a' - 'A');
else
hash += c;
hash *= 38501U;
}
if (llen)
*llen = i;
return hash;
}
SOFIA_END_DECLS
#endif /** MSG_MCLASS_HASH_H */