postgresql/contrib/soundex/soundex.c

90 lines
1.9 KiB
C

/*****************************************************************************/
/* soundex.c */
/*****************************************************************************/
#include <string.h>
#include <stdio.h>
#include "postgres.h" /* for char16, etc. */
#include "utils/palloc.h" /* for palloc */
#include "libpq-fe.h" /* for TUPLE */
#include <stdio.h>
#include <ctype.h>
/* prototype for soundex function */
char *soundex(char *instr, char *outstr);
text *
text_soundex(text *t)
{
/* ABCDEFGHIJKLMNOPQRSTUVWXYZ */
char *table = "01230120022455012623010202";
int count = 0;
text *new_t;
char outstr[6 + 1]; /* max length of soundex is 6 */
char *instr;
/* make a null-terminated string */
instr = palloc(VARSIZE(t) + 1);
memcpy(instr, VARDATA(t), VARSIZE(t) - VARHDRSZ);
instr[VARSIZE(t) - VARHDRSZ] = (char) 0;
/* load soundex into outstr */
soundex(instr, outstr);
/* Now the outstr contains the soundex of instr */
/* copy outstr to new_t */
new_t = (text *) palloc(strlen(outstr) + VARHDRSZ);
memset(new_t, 0, strlen(outstr) + 1);
VARSIZE(new_t) = strlen(outstr) + VARHDRSZ;
memcpy((void *) VARDATA(new_t),
(void *) outstr,
strlen(outstr));
/* free instr */
pfree(instr);
return (new_t);
}
char *
soundex(char *instr, char *outstr)
{ /* ABCDEFGHIJKLMNOPQRSTUVWXYZ */
char *table = "01230120022455012623010202";
int count = 0;
while (!isalpha(instr[0]) && instr[0])
++instr;
if (!instr[0])
{ /* Hey! Where'd the string go? */
outstr[0] = (char) 0;
return outstr;
}
if (toupper(instr[0]) == 'P' && toupper(instr[1]) == 'H')
{
instr[0] = 'F';
instr[1] = 'A';
}
*outstr++ = (char) toupper(*instr++);
while (*instr && count < 5)
{
if (isalpha(*instr) && *instr != *(instr - 1))
{
*outstr = table[toupper(instr[0]) - 'A'];
if (*outstr != '0')
{
++outstr;
++count;
}
}
++instr;
}
*outstr = '\0';
return (outstr);
}