postgresql/contrib/dict_int/dict_int.c
Tom Lane e3e3087d87 Fix bogus code in contrib/ tsearch dictionary examples.
Both dict_int and dict_xsyn were blithely assuming that whatever memory
palloc gives back will be pre-zeroed.  This would typically work for
just about long enough to run their regression tests, and no longer :-(.

The pre-9.0 code in dict_xsyn was even lamer than that, as it would
happily give back a pointer to the result of palloc(0), encouraging
its caller to access off the end of memory.  Again, this would just
barely fail to fail as long as memory contained nothing but zeroes.

Per a report from Rodrigo Hjort that code based on these examples
didn't work reliably.
2011-11-03 19:17:48 -04:00

100 lines
1.9 KiB
C

/*-------------------------------------------------------------------------
*
* dict_int.c
* Text search dictionary for integers
*
* Copyright (c) 2007-2011, PostgreSQL Global Development Group
*
* IDENTIFICATION
* contrib/dict_int/dict_int.c
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include "commands/defrem.h"
#include "tsearch/ts_public.h"
PG_MODULE_MAGIC;
typedef struct
{
int maxlen;
bool rejectlong;
} DictInt;
PG_FUNCTION_INFO_V1(dintdict_init);
Datum dintdict_init(PG_FUNCTION_ARGS);
PG_FUNCTION_INFO_V1(dintdict_lexize);
Datum dintdict_lexize(PG_FUNCTION_ARGS);
Datum
dintdict_init(PG_FUNCTION_ARGS)
{
List *dictoptions = (List *) PG_GETARG_POINTER(0);
DictInt *d;
ListCell *l;
d = (DictInt *) palloc0(sizeof(DictInt));
d->maxlen = 6;
d->rejectlong = false;
foreach(l, dictoptions)
{
DefElem *defel = (DefElem *) lfirst(l);
if (pg_strcasecmp(defel->defname, "MAXLEN") == 0)
{
d->maxlen = atoi(defGetString(defel));
}
else if (pg_strcasecmp(defel->defname, "REJECTLONG") == 0)
{
d->rejectlong = defGetBoolean(defel);
}
else
{
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("unrecognized intdict parameter: \"%s\"",
defel->defname)));
}
}
PG_RETURN_POINTER(d);
}
Datum
dintdict_lexize(PG_FUNCTION_ARGS)
{
DictInt *d = (DictInt *) PG_GETARG_POINTER(0);
char *in = (char *) PG_GETARG_POINTER(1);
char *txt = pnstrdup(in, PG_GETARG_INT32(2));
TSLexeme *res = palloc0(sizeof(TSLexeme) * 2);
res[1].lexeme = NULL;
if (PG_GETARG_INT32(2) > d->maxlen)
{
if (d->rejectlong)
{
/* reject by returning void array */
pfree(txt);
res[0].lexeme = NULL;
}
else
{
/* trim integer */
txt[d->maxlen] = '\0';
res[0].lexeme = txt;
}
}
else
{
res[0].lexeme = txt;
}
PG_RETURN_POINTER(res);
}