translate function (BUG?)

Hello all,

I was looking at the translate function and I think that it does not
behave quite right. I modified the translate function in
oracle_compat.c (included below) to make work more like its Oracle
counterpart. It seems to work but it returns the following message:
NOTICE: PortalHeapMemoryFree: 0x8241fcc not in alloc set!

Below are the Oracle and Postgres session transcripts.

select translate('edwin', 'wi', 'af') from dual;
ORACLE:
TRANS
-----
edafn
1 row selected.

POSTGRES
translate
---------
edain
(1 row)

select translate('edwin', 'wi', 'a') from dual;
ORACLE
TRAN
----
edan
1 row selected.

POSTGRES
translate
---------
edain
(1 row)

select length(translate('edwin', 'wi', 'a')) from dual;
ORACLE
LENGTH(TRA
----------
4
1 row selected.

POSTGRES
length
------
5
(1 row)

-----------------------NEW
FUNCTION--------------------------------------
text *
translate(text *string, text *from, text *to)
{
text *ret;
char *ptr_ret, *from_ptr, *to_ptr, *source, *target, *temp, rep;
int m, fromlen, tolen, retlen, i;

if ((string == (text *) NULL) ||
((m = VARSIZE(string) - VARHDRSZ) <= 0))
return string;

target = (char *) palloc(VARSIZE(string) - VARHDRSZ);
source = VARDATA(string);
temp = target;

fromlen = VARSIZE(from) - VARHDRSZ;
from_ptr = VARDATA(from);
tolen = VARSIZE(to) - VARHDRSZ;
to_ptr = VARDATA(to);
retlen = 0;
while (m--)
{
rep = *source;
for(i=0;i<fromlen;i++) {
if(from_ptr[i] == *source) {
if(i < tolen) {
rep = to_ptr[i];
} else {
rep = 0;
}
break;
}
}
if(rep != 0) {
*target++ = rep;
retlen++;
}
source++;
}

ret = (text *) palloc(retlen + VARHDRSZ);
VARSIZE(ret) = retlen + VARHDRSZ;
ptr_ret = VARDATA(ret);
for(i=0;i<retlen;i++) {
*ptr_ret++ = temp[i];
}
pfree(target);
return ret;
}

Thanks,
Edwin S. Ramirez