Automatically generate node support functions

Add a script to automatically generate the node support functions
(copy, equal, out, and read, as well as the node tags enum) from the
struct definitions.

For each of the four node support files, it creates two include files,
e.g., copyfuncs.funcs.c and copyfuncs.switch.c, to include in the main
file.  All the scaffolding of the main file stays in place.

I have tried to mostly make the coverage of the output match what is
currently there.  For example, one could now do out/read coverage of
utility statement nodes, but I have manually excluded those for now.
The reason is mainly that it's easier to diff the before and after,
and adding a bunch of stuff like this might require a separate
analysis and review.

Subtyping (TidScan -> Scan) is supported.

For the hard cases, you can just write a manual function and exclude
generating one.  For the not so hard cases, there is a way of
annotating struct fields to get special behaviors.  For example,
pg_node_attr(equal_ignore) has the field ignored in equal functions.

(In this patch, I have only ifdef'ed out the code to could be removed,
mainly so that it won't constantly have merge conflicts.  It will be
deleted in a separate patch.  All the code comments that are worth
keeping from those sections have already been moved to the header
files where the structs are defined.)

Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://www.postgresql.org/message-id/flat/c1097590-a6a4-486a-64b1-e1f9cc0533ce%40enterprisedb.com

2 files changed, 53 insertions, 0 deletions

diff --git a/src/tools/msvc/Solution.pm b/src/tools/msvc/Solution.pm
index 52ff56ba83..b8b1728df7 100644
--- a/src/tools/msvc/Solution.pm
+++ b/src/tools/msvc/Solution.pm
@@ -839,6 +839,54 @@ EOF
 		close($chs);
 	}
 
+	if (IsNewer(
+			'src/backend/nodes/node-support-stamp',
+			'src/backend/nodes/gen_node_support.pl'))
+	{
+		# XXX duplicates src/backend/nodes/Makefile
+
+		my @node_headers = qw(
+		  nodes/nodes.h
+		  nodes/execnodes.h
+		  nodes/plannodes.h
+		  nodes/primnodes.h
+		  nodes/pathnodes.h
+		  nodes/extensible.h
+		  nodes/parsenodes.h
+		  nodes/replnodes.h
+		  nodes/value.h
+		  commands/trigger.h
+		  commands/event_trigger.h
+		  foreign/fdwapi.h
+		  access/amapi.h
+		  access/tableam.h
+		  access/tsmapi.h
+		  utils/rel.h
+		  nodes/supportnodes.h
+		  executor/tuptable.h
+		  nodes/lockoptions.h
+		  access/sdir.h
+		);
+
+		chdir('src/backend/nodes');
+
+		my @node_files = map { "../../../src/include/$_" } @node_headers;
+
+		system("perl gen_node_support.pl @node_files");
+		open(my $f, '>', 'node-support-stamp')
+		  || confess "Could not touch node-support-stamp";
+		close($f);
+		chdir('../../..');
+	}
+
+	if (IsNewer(
+			'src/include/nodes/nodetags.h',
+			'src/backend/nodes/nodetags.h'))
+	{
+		copyFile('src/backend/nodes/nodetags.h',
+			'src/include/nodes/nodetags.h');
+	}
+
 	open(my $o, '>', "doc/src/sgml/version.sgml")
 	  || croak "Could not write to version.sgml\n";
 	print $o <<EOF;
diff --git a/src/tools/pgindent/exclude_file_patterns b/src/tools/pgindent/exclude_file_patterns
index f08180b0d0..f5c8857e31 100644
--- a/src/tools/pgindent/exclude_file_patterns
+++ b/src/tools/pgindent/exclude_file_patterns
@@ -7,6 +7,11 @@ src/include/port/atomics/
 # This contains C++ constructs that confuse pgindent.
 src/include/jit/llvmjit\.h$
 #
+# These are generated files with incomplete code fragments that
+# confuse pgindent.
+src/backend/nodes/\w+\.funcs\.c$
+src/backend/nodes/\w+\.switch\.c$
+#
 # This confuses pgindent, and it's a derived file anyway.
 src/backend/utils/fmgrtab\.c$
 #