diff --git a/src/backend/access/common/Makefile b/src/backend/access/common/Makefile
index 1fa6de0823a5e8cf3d71052499452f53a1821d2d..d4b8132a9739f430f1acb18934383cd64a68fb1d 100644
--- a/src/backend/access/common/Makefile
+++ b/src/backend/access/common/Makefile
@@ -12,7 +12,7 @@ subdir = src/backend/access/common
top_builddir = ../../../..
include $(top_builddir)/src/Makefile.global
-OBJS = heaptuple.o indextuple.o printtup.o reloptions.o scankey.o \
- tupconvert.o tupdesc.o
+OBJS = heaptuple.o indextuple.o printsimple.o printtup.o reloptions.o \
+ scankey.o tupconvert.o tupdesc.o
include $(top_srcdir)/src/backend/common.mk
diff --git a/src/backend/access/common/printsimple.c b/src/backend/access/common/printsimple.c
new file mode 100644
index 0000000000000000000000000000000000000000..420de65e2073d18f63b0768573b74beab199793b
--- /dev/null
+++ b/src/backend/access/common/printsimple.c
@@ -0,0 +1,110 @@
+/*-------------------------------------------------------------------------
+ *
+ * printsimple.c
+ * Routines to print out tuples containing only a limited range of
+ * builtin types without catalog access. This is intended for
+ * backends that don't have catalog access because they are not bound
+ * to a specific database, such as some walsender processes. It
+ * doesn't handle standalone backends or protocol versions other than
+ * 3.0, because we don't need such handling for current applications.
+ *
+ * Portions Copyright (c) 1996-2017, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * IDENTIFICATION
+ * src/backend/access/common/printsimple.c
+ *
+ *-------------------------------------------------------------------------
+ */
+#include "postgres.h"
+
+#include "access/printsimple.h"
+#include "catalog/pg_type.h"
+#include "fmgr.h"
+#include "libpq/pqformat.h"
+
+/*
+ * At startup time, send a RowDescription message.
+ */
+void
+printsimple_startup(DestReceiver *self, int operation, TupleDesc tupdesc)
+{
+ StringInfoData buf;
+ int i;
+
+ pq_beginmessage(&buf, 'T'); /* RowDescription */
+ pq_sendint(&buf, tupdesc->natts, 2);
+
+ for (i = 0; i < tupdesc->natts; ++i)
+ {
+ Form_pg_attribute attr = tupdesc->attrs[i];
+
+ pq_sendstring(&buf, NameStr(attr->attname));
+ pq_sendint(&buf, 0, 4); /* table oid */
+ pq_sendint(&buf, 0, 2); /* attnum */
+ pq_sendint(&buf, (int) attr->atttypid, 4);
+ pq_sendint(&buf, attr->attlen, 2);
+ pq_sendint(&buf, attr->atttypmod, 4);
+ pq_sendint(&buf, 0, 2); /* format code */
+ }
+
+ pq_endmessage(&buf);
+}
+
+/*
+ * For each tuple, send a DataRow message.
+ */
+bool
+printsimple(TupleTableSlot *slot, DestReceiver *self)
+{
+ TupleDesc tupdesc = slot->tts_tupleDescriptor;
+ StringInfoData buf;
+ int i;
+
+ /* Make sure the tuple is fully deconstructed */
+ slot_getallattrs(slot);
+
+ /* Prepare and send message */
+ pq_beginmessage(&buf, 'D');
+ pq_sendint(&buf, tupdesc->natts, 2);
+
+ for (i = 0; i < tupdesc->natts; ++i)
+ {
+ Form_pg_attribute attr = tupdesc->attrs[i];
+ Datum value;
+
+ if (slot->tts_isnull[i])
+ {
+ pq_sendint(&buf, -1, 4);
+ continue;
+ }
+
+ value = slot->tts_values[i];
+
+ /*
+ * We can't call the regular type output functions here because we
+ * might not have catalog access. Instead, we must hard-wire
+ * knowledge of the required types.
+ */
+ switch (attr->atttypid)
+ {
+ case TEXTOID:
+ {
+ text *t = DatumGetTextPP(value);
+
+ pq_sendcountedtext(&buf,
+ VARDATA_ANY(t),
+ VARSIZE_ANY_EXHDR(t),
+ false);
+ }
+ break;
+
+ default:
+ elog(ERROR, "unsupported type OID: %u", attr->atttypid);
+ }
+ }
+
+ pq_endmessage(&buf);
+
+ return true;
+}
diff --git a/src/backend/tcop/dest.c b/src/backend/tcop/dest.c
index da39f43f38c3e7be68d5732faf32486ae7cbb7b0..28081c37654a8787e9423e75c6f768997d6872ca 100644
--- a/src/backend/tcop/dest.c
+++ b/src/backend/tcop/dest.c
@@ -28,6 +28,7 @@
#include "postgres.h"
+#include "access/printsimple.h"
#include "access/printtup.h"
#include "access/xact.h"
#include "commands/copy.h"
@@ -76,6 +77,11 @@ static DestReceiver debugtupDR = {
DestDebug
};
+static DestReceiver printsimpleDR = {
+ printsimple, printsimple_startup, donothingCleanup, donothingCleanup,
+ DestRemoteSimple
+};
+
static DestReceiver spi_printtupDR = {
spi_printtup, spi_dest_startup, donothingCleanup, donothingCleanup,
DestSPI
@@ -108,6 +114,9 @@ CreateDestReceiver(CommandDest dest)
case DestRemoteExecute:
return printtup_create_DR(dest);
+ case DestRemoteSimple:
+ return &printsimpleDR;
+
case DestNone:
return &donothingDR;
@@ -151,6 +160,7 @@ EndCommand(const char *commandTag, CommandDest dest)
{
case DestRemote:
case DestRemoteExecute:
+ case DestRemoteSimple:
/*
* We assume the commandTag is plain ASCII and therefore requires
@@ -191,6 +201,7 @@ NullCommand(CommandDest dest)
{
case DestRemote:
case DestRemoteExecute:
+ case DestRemoteSimple:
/*
* tell the fe that we saw an empty query string. In protocols
@@ -233,6 +244,7 @@ ReadyForQuery(CommandDest dest)
{
case DestRemote:
case DestRemoteExecute:
+ case DestRemoteSimple:
if (PG_PROTOCOL_MAJOR(FrontendProtocol) >= 3)
{
StringInfoData buf;
diff --git a/src/include/access/printsimple.h b/src/include/access/printsimple.h
new file mode 100644
index 0000000000000000000000000000000000000000..3f3e7a38400d5d719e8a7f000e77ab3fa4c9b61e
--- /dev/null
+++ b/src/include/access/printsimple.h
@@ -0,0 +1,23 @@
+/*-------------------------------------------------------------------------
+ *
+ * printsimple.h
+ * print simple tuples without catalog access
+ *
+ * Portions Copyright (c) 1996-2017, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * src/include/access/printsimple.h
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#ifndef PRINTSIMPLE_H
+#define PRINTSIMPLE_H
+
+#include "tcop/dest.h"
+
+extern bool printsimple(TupleTableSlot *slot, DestReceiver *self);
+extern void printsimple_startup(DestReceiver *self, int operation,
+ TupleDesc tupdesc);
+
+#endif /* PRINTSIMPLE_H */
diff --git a/src/include/tcop/dest.h b/src/include/tcop/dest.h
index 93f9b7463abe2dd8d06a98b19fc287e3b7155c79..c459af2e139ee598b7ee1cc6c64d7b3cf029025a 100644
--- a/src/include/tcop/dest.h
+++ b/src/include/tcop/dest.h
@@ -89,6 +89,7 @@ typedef enum
DestDebug, /* results go to debugging output */
DestRemote, /* results sent to frontend process */
DestRemoteExecute, /* sent to frontend, in Execute command */
+ DestRemoteSimple, /* sent to frontend, w/no catalog access */
DestSPI, /* results sent to SPI manager */
DestTuplestore, /* results sent to Tuplestore */
DestIntoRel, /* results sent to relation (SELECT INTO) */