mirror of
https://github.com/MariaDB/server.git
synced 2025-10-31 02:46:29 +01:00
106 lines
3.4 KiB
C
106 lines
3.4 KiB
C
/* Copyright (c) 2000, 2002, 2004, 2007 MySQL AB
|
|
Use is subject to license terms
|
|
|
|
This program 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; version 2 of the License.
|
|
|
|
This program 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 Street, Fifth Floor, Boston, MA 02110-1335 USA */
|
|
|
|
/****************************************************************
|
|
* SOUNDEX ALGORITHM in C *
|
|
* *
|
|
* The basic Algorithm source is taken from EDN Nov. *
|
|
* 14, 1985 pg. 36. *
|
|
* *
|
|
* As a test Those in Illinois will find that the *
|
|
* first group of numbers in their drivers license *
|
|
* number is the soundex number for their last name. *
|
|
* *
|
|
* RHW PC-IBBS ID. #1230 *
|
|
* *
|
|
* As an extension if remove_garbage is set then all non- *
|
|
* alpha characters are skipped *
|
|
* *
|
|
* Note, that this implementation corresponds to the *
|
|
* original version of the algorithm, not to the more *
|
|
* popular "enhanced" version, described by Knuth. *
|
|
****************************************************************/
|
|
|
|
#include "mysys_priv.h"
|
|
#include <m_ctype.h>
|
|
#include "my_static.h"
|
|
|
|
static char get_scode(CHARSET_INFO * cs, char **ptr,pbool remove_garbage);
|
|
|
|
/* outputed string is 4 byte long */
|
|
/* out_pntr can be == in_pntr */
|
|
|
|
void soundex(CHARSET_INFO * cs,register char * out_pntr, char * in_pntr,
|
|
pbool remove_garbage)
|
|
{
|
|
char ch,last_ch;
|
|
reg3 char * end;
|
|
register const uchar *map=cs->to_upper;
|
|
|
|
if (remove_garbage)
|
|
{
|
|
while (*in_pntr && !my_isalpha(cs,*in_pntr)) /* Skip pre-space */
|
|
in_pntr++;
|
|
}
|
|
*out_pntr++ = map[(uchar)*in_pntr]; /* Copy first letter */
|
|
last_ch = get_scode(cs,&in_pntr,0); /* code of the first letter */
|
|
/* for the first 'double-letter */
|
|
/* check. */
|
|
end=out_pntr+3; /* Loop on input letters until */
|
|
/* end of input (null) or output */
|
|
/* letter code count = 3 */
|
|
|
|
in_pntr++;
|
|
while (out_pntr < end && (ch = get_scode(cs,&in_pntr,remove_garbage)) != 0)
|
|
{
|
|
in_pntr++;
|
|
if ((ch != '0') && (ch != last_ch)) /* if not skipped or double */
|
|
{
|
|
*out_pntr++ = ch; /* letter, copy to output */
|
|
} /* for next double-letter check */
|
|
last_ch = ch; /* save code of last input letter */
|
|
}
|
|
while (out_pntr < end)
|
|
*out_pntr++ = '0';
|
|
*out_pntr=0; /* end string */
|
|
return;
|
|
} /* soundex */
|
|
|
|
|
|
/*
|
|
If alpha, map input letter to soundex code.
|
|
If not alpha and remove_garbage is set then skip to next char
|
|
else return 0
|
|
*/
|
|
|
|
static char get_scode(CHARSET_INFO * cs,char **ptr, pbool remove_garbage)
|
|
{
|
|
uchar ch;
|
|
|
|
if (remove_garbage)
|
|
{
|
|
while (**ptr && !my_isalpha(cs,**ptr))
|
|
(*ptr)++;
|
|
}
|
|
ch=my_toupper(cs,**ptr);
|
|
if (ch < 'A' || ch > 'Z')
|
|
{
|
|
if (my_isalpha(cs,ch)) /* If extended alfa (country spec) */
|
|
return '0'; /* threat as vokal */
|
|
return 0; /* Can't map */
|
|
}
|
|
return(soundex_map[ch-'A']);
|
|
} /* get_scode */
|