Fix incorrect tests for undef Perl values in some places in plperl.c.

The correct test for defined-ness is SvOK(sv), not anything involving
SvTYPE.  Per bug #3415 from Matt Taylor.
Back-patch as far as 8.0; no apparent problem in 7.x.

diff --git a/src/pl/plperl/plperl.c b/src/pl/plperl/plperl.c
index ff484f4dbe015deaaba209b524dd7d403ce35e67..0c32bb4718ee02344d4644fb6393a51b70e3f602 100644 (file)
--- a/src/pl/plperl/plperl.c
+++ b/src/pl/plperl/plperl.c
@@ -1,7 +1,7 @@
 /**********************************************************************
  * plperl.c - perl as a procedural language for PostgreSQL
  *
- *   $PostgreSQL: pgsql/src/pl/plperl/plperl.c,v 1.128 2007/04/02 03:49:41 tgl Exp $
+ *   $PostgreSQL: pgsql/src/pl/plperl/plperl.c,v 1.129 2007/06/28 17:49:59 tgl Exp $
  *
  **********************************************************************/
 
@@ -547,7 +547,7 @@ plperl_build_tuple_result(HV *perlhash, AttInMetadata *attinmeta)
                    (errcode(ERRCODE_UNDEFINED_COLUMN),
                     errmsg("Perl hash contains nonexistent column \"%s\"",
                            key)));
-       if (SvOK(val) && SvTYPE(val) != SVt_NULL)
+       if (SvOK(val))
            values[attn - 1] = SvPV(val, PL_na);
    }
    hv_iterinit(perlhash);
@@ -743,7 +743,7 @@ plperl_modify_tuple(HV *hvTD, TriggerData *tdata, HeapTuple otup)
                         &typinput, &typioparam);
        fmgr_info(typinput, &finfo);
        atttypmod = tupdesc->attrs[attn - 1]->atttypmod;
-       if (SvOK(val) && SvTYPE(val) != SVt_NULL)
+       if (SvOK(val))
        {
            modvalues[slotsused] = InputFunctionCall(&finfo,
                                                     SvPV(val, PL_na),
@@ -1197,9 +1197,10 @@ plperl_func_handler(PG_FUNCTION_ARGS)
         * If the Perl function returned an arrayref, we pretend that it
         * called return_next() for each element of the array, to handle old
         * SRFs that didn't know about return_next(). Any other sort of return
-        * value is an error.
+        * value is an error, except undef which means return an empty set.
         */
-       if (SvTYPE(perlret) == SVt_RV &&
+       if (SvOK(perlret) &&
+           SvTYPE(perlret) == SVt_RV &&
            SvTYPE(SvRV(perlret)) == SVt_PVAV)
        {
            int         i = 0;
@@ -1212,7 +1213,7 @@ plperl_func_handler(PG_FUNCTION_ARGS)
                i++;
            }
        }
-       else if (SvTYPE(perlret) != SVt_NULL)
+       else if (SvOK(perlret))
        {
            ereport(ERROR,
                    (errcode(ERRCODE_DATATYPE_MISMATCH),
@@ -1228,7 +1229,7 @@ plperl_func_handler(PG_FUNCTION_ARGS)
        }
        retval = (Datum) 0;
    }
-   else if (SvTYPE(perlret) == SVt_NULL)
+   else if (!SvOK(perlret))
    {
        /* Return NULL if Perl code returned undef */
        if (rsi && IsA(rsi, ReturnSetInfo))
@@ -1335,7 +1336,7 @@ plperl_trigger_handler(PG_FUNCTION_ARGS)
    if (SPI_finish() != SPI_OK_FINISH)
        elog(ERROR, "SPI_finish() failed");
 
-   if (!(perlret && SvOK(perlret) && SvTYPE(perlret) != SVt_NULL))
+   if (perlret == NULL || !SvOK(perlret))
    {
        /* undef result means go ahead with original tuple */
        TriggerData *trigdata = ((TriggerData *) fcinfo->context);
@@ -1900,7 +1901,7 @@ plperl_return_next(SV *sv)
        Datum       ret;
        bool        isNull;
 
-       if (SvOK(sv) && SvTYPE(sv) != SVt_NULL)
+       if (SvOK(sv))
        {
            char       *val = SvPV(sv, PL_na);
 
@@ -2292,7 +2293,7 @@ plperl_spi_exec_prepared(char *query, HV *attr, int argc, SV **argv)
 
        for (i = 0; i < argc; i++)
        {
-           if (SvTYPE(argv[i]) != SVt_NULL)
+           if (SvOK(argv[i]))
            {
                argvalues[i] = InputFunctionCall(&qdesc->arginfuncs[i],
                                                 SvPV(argv[i], PL_na),
@@ -2423,7 +2424,7 @@ plperl_spi_query_prepared(char *query, int argc, SV **argv)
 
        for (i = 0; i < argc; i++)
        {
-           if (SvTYPE(argv[i]) != SVt_NULL)
+           if (SvOK(argv[i]))
            {
                argvalues[i] = InputFunctionCall(&qdesc->arginfuncs[i],
                                                 SvPV(argv[i], PL_na),