PL/Perl portability fix: avoid including XSUB.h in plperl.c.

Back-patch of commit bebe174,
which see for more info.

Patch by me, with some help from Ashutosh Sharma

Discussion: https://postgr.es/m/CANFyU97OVQ3+Mzfmt3MhuUm5NwPU=-FtbNH5Eb7nZL9ua8=rcA@mail.gmail.com

Author: tglsfdc

contrib/hstore_plperl/hstore_plperl.c

@@ -13,6 +13,7 @@ PG_FUNCTION_INFO_V1(hstore_to_plperl);
 Datum
 hstore_to_plperl(PG_FUNCTION_ARGS)
 {
+	dTHX;
 	HStore	   *in = PG_GETARG_HS(0);
 	int			i;
 	int			count = HS_COUNT(in);
@@ -45,16 +46,15 @@ PG_FUNCTION_INFO_V1(plperl_to_hstore);
 Datum
 plperl_to_hstore(PG_FUNCTION_ARGS)
 {
-	HV		   *hv;
+	dTHX;
+	HV		   *hv = (HV *) SvRV((SV *) PG_GETARG_POINTER(0));
 	HE		   *he;
 	int32		buflen;
 	int32		i;
 	int32		pcount;
 	HStore	   *out;
 	Pairs	   *pairs;
 
-	hv = (HV *) SvRV((SV *) PG_GETARG_POINTER(0));
-
 	pcount = hv_iterinit(hv);
 
 	pairs = palloc(pcount * sizeof(Pairs));

src/pl/plperl/SPI.xs

@@ -9,44 +9,16 @@
 
 /* this must be first: */
 #include "postgres.h"
-#include "mb/pg_wchar.h"       /* for GetDatabaseEncoding */
 
 /* Defined by Perl */
 #undef _
 
 /* perl stuff */
+#define PG_NEED_PERL_XSUB_H
 #include "plperl.h"
 #include "plperl_helpers.h"
 
 
-/*
- * Interface routine to catch ereports and punt them to Perl
- */
-static void
-do_plperl_return_next(SV *sv)
-{
-	MemoryContext oldcontext = CurrentMemoryContext;
-
-	PG_TRY();
-	{
-		plperl_return_next(sv);
-	}
-	PG_CATCH();
-	{
-		ErrorData  *edata;
-
-		/* Must reset elog.c's state */
-		MemoryContextSwitchTo(oldcontext);
-		edata = CopyErrorData();
-		FlushErrorState();
-
-		/* Punt the error to Perl */
-		croak_cstr(edata->message);
-	}
-	PG_END_TRY();
-}
-
-
 MODULE = PostgreSQL::InServer::SPI PREFIX = spi_
 
 PROTOTYPES: ENABLE
@@ -76,7 +48,7 @@ void
 spi_return_next(rv)
 	SV *rv;
 	CODE:
-		do_plperl_return_next(rv);
+		plperl_return_next(rv);
 
 SV *
 spi_spi_query(sv)

src/pl/plperl/Util.xs

@@ -15,53 +15,15 @@
 #include "fmgr.h"
 #include "utils/builtins.h"
 #include "utils/bytea.h"       /* for byteain & byteaout */
-#include "mb/pg_wchar.h"       /* for GetDatabaseEncoding */
+
 /* Defined by Perl */
 #undef _
 
 /* perl stuff */
+#define PG_NEED_PERL_XSUB_H
 #include "plperl.h"
 #include "plperl_helpers.h"
 
-/*
- * Implementation of plperl's elog() function
- *
- * If the error level is less than ERROR, we'll just emit the message and
- * return.  When it is ERROR, elog() will longjmp, which we catch and
- * turn into a Perl croak().  Note we are assuming that elog() can't have
- * any internal failures that are so bad as to require a transaction abort.
- *
- * This is out-of-line to suppress "might be clobbered by longjmp" warnings.
- */
-static void
-do_util_elog(int level, SV *msg)
-{
-	MemoryContext oldcontext = CurrentMemoryContext;
-	char	   * volatile cmsg = NULL;
-
-	PG_TRY();
-	{
-		cmsg = sv2cstr(msg);
-		elog(level, "%s", cmsg);
-		pfree(cmsg);
-	}
-	PG_CATCH();
-	{
-		ErrorData  *edata;
-
-		/* Must reset elog.c's state */
-		MemoryContextSwitchTo(oldcontext);
-		edata = CopyErrorData();
-		FlushErrorState();
-
-		if (cmsg)
-			pfree(cmsg);
-
-		/* Punt the error to Perl */
-		croak_cstr(edata->message);
-	}
-	PG_END_TRY();
-}
 
 static text *
 sv2text(SV *sv)
@@ -105,7 +67,7 @@ util_elog(level, msg)
             level = ERROR;
         if (level < DEBUG5)
             level = DEBUG5;
-        do_util_elog(level, msg);
+        plperl_util_elog(level, msg);
 
 SV *
 util_quote_literal(sv)