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/* $Header: /cvsroot/pgsql/contrib/soundex/Attic/soundex.c,v 1.11 2001/03/22 03:59:10 momjian Exp $ */
#include "postgres.h"
#include <ctype.h>
#include "fmgr.h"
#include "utils/builtins.h"
Datum text_soundex(PG_FUNCTION_ARGS);
static void soundex(const char *instr, char *outstr);
#define SOUNDEX_LEN 4
#define _textin(str) DirectFunctionCall1(textin, CStringGetDatum(str))
#define _textout(str) DatumGetPointer(DirectFunctionCall1(textout, PointerGetDatum(str)))
#ifndef SOUNDEX_TEST
/*
* SQL function: text_soundex(text) returns text
*/
PG_FUNCTION_INFO_V1(text_soundex);
Datum
text_soundex(PG_FUNCTION_ARGS)
{
char outstr[SOUNDEX_LEN + 1];
char *arg;
arg = _textout(PG_GETARG_TEXT_P(0));
soundex(arg, outstr);
PG_RETURN_TEXT_P(_textin(outstr));
}
#endif /* not SOUNDEX_TEST */
/* ABCDEFGHIJKLMNOPQRSTUVWXYZ */
static const char *soundex_table = "01230120022455012623010202";
#define soundex_code(letter) soundex_table[toupper((unsigned char) (letter)) - 'A']
static void
soundex(const char *instr, char *outstr)
{
int count;
AssertArg(instr);
AssertArg(outstr);
outstr[SOUNDEX_LEN] = '\0';
/* Skip leading non-alphabetic characters */
while (!isalpha((unsigned char) instr[0]) && instr[0])
++instr;
/* No string left */
if (!instr[0])
{
outstr[0] = (char) 0;
return;
}
/* Take the first letter as is */
*outstr++ = (char) toupper((unsigned char) *instr++);
count = 1;
while (*instr && count < SOUNDEX_LEN)
{
if (isalpha((unsigned char) *instr) &&
soundex_code(*instr) != soundex_code(*(instr - 1)))
{
*outstr = soundex_code(instr[0]);
if (*outstr != '0')
{
++outstr;
++count;
}
}
++instr;
}
/* Fill with 0's */
while (count < SOUNDEX_LEN)
{
*outstr = '0';
++outstr;
++count;
}
}
#ifdef SOUNDEX_TEST
int
main(int argc, char *argv[])
{
if (argc < 2)
{
fprintf(stderr, "usage: %s string\n", argv[0]);
return 1;
}
else
{
char output[SOUNDEX_LEN + 1];
soundex(argv[1], output);
printf("soundex(%s) = %s\n", argv[1], output);
return 0;
}
}
#endif /* SOUNDEX_TEST */
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