From 40da2f9b7f9781093b443a2ed02237509f224f83 Mon Sep 17 00:00:00 2001
From: John Naylor <jcnaylor@gmail.com>
Date: Mon, 16 Apr 2018 00:46:47 +0700
Subject: [PATCH] Remove special array handling from bootstrap.c

Formerly, Catalog.pm turned a given C array type declaration in the catalog
header files into a SQL type, i.e. 'foo[]'.  Along the way, genbki.pl
turned this into '_foo' for the purpose of type lookups, but wrote 'foo[]'
to postgres.bki. During bootstrap, bootscanner.l had to have a special
case rule to tokenize this, and then MapArrayTypeName() would turn
'foo[]' into '_foo' one more time.

This seems pointless, so do the right thing in Catalog.pm and rip out all
downstream array type munging logic. It also seems strange to single out
array type names to check that the length is less than NAMEDATALEN, so this
behavior is not kept.

The SGML documentation is not updated, since it only mentions array types
in the context of header files.
---
 src/backend/bootstrap/bootscanner.l |  6 ------
 src/backend/bootstrap/bootstrap.c   | 30 ------------------------------
 src/backend/catalog/Catalog.pm      |  8 ++++++--
 src/backend/catalog/genbki.pl       |  8 ++------
 src/include/bootstrap/bootstrap.h   |  2 --
 5 files changed, 8 insertions(+), 46 deletions(-)

diff --git a/src/backend/bootstrap/bootscanner.l b/src/backend/bootstrap/bootscanner.l
index d9af1cb..ab474e6 100644
--- a/src/backend/bootstrap/bootscanner.l
+++ b/src/backend/bootstrap/bootscanner.l
@@ -65,10 +65,8 @@ static int	yyline = 1;			/* line number for error reporting */
 %option prefix="boot_yy"

-D		[0-9]
 id		[A-Za-z0-9_]+
 sid		\"([^\"])*\"
-arrayid [A-Za-z0-9_]+\[{D}*\]

 %%

@@ -111,10 +109,6 @@ insert			{ return INSERT_TUPLE; }
 "NOT"			{ return XNOT; }
 "NULL"			{ return XNULL; }

-{arrayid}		{
-					yylval.str = MapArrayTypeName(yytext);
-					return ID;
-				}
 {id}			{
 					yylval.str = scanstr(yytext);
 					return ID;
diff --git a/src/backend/bootstrap/bootstrap.c b/src/backend/bootstrap/bootstrap.c
index 59cd4b1..a148bdc 100644
--- a/src/backend/bootstrap/bootstrap.c
+++ b/src/backend/bootstrap/bootstrap.c
@@ -1037,36 +1037,6 @@ AllocateAttribute(void)
 }

 /*
- *		MapArrayTypeName
- *
- * Given a type name, produce the corresponding array type name by prepending
- * '_' and truncating as needed to fit in NAMEDATALEN-1 bytes.  This is only
- * used in bootstrap mode, so we can get away with assuming that the input is
- * ASCII and we don't need multibyte-aware truncation.
- *
- * The given string normally ends with '[]' or '[digits]'; we discard that.
- *
- * The result is a palloc'd string.
- */
-char *
-MapArrayTypeName(const char *s)
-{
-	int			i,
-				j;
-	char		newStr[NAMEDATALEN];
-
-	newStr[0] = '_';
-	j = 1;
-	for (i = 0; i < NAMEDATALEN - 2 && s[i] != '['; i++, j++)
-		newStr[j] = s[i];
-
-	newStr[j] = '\0';
-
-	return pstrdup(newStr);
-}
-
-
-/*
  *	index_register() -- record an index that has been set up for building
  *						later.
  *
diff --git a/src/backend/catalog/Catalog.pm b/src/backend/catalog/Catalog.pm
index c32ce2f..07057c1 100644
--- a/src/backend/catalog/Catalog.pm
+++ b/src/backend/catalog/Catalog.pm
@@ -161,10 +161,14 @@ sub ParseHeader
 					{
 						$atttype = $RENAME_ATTTYPE{$atttype};
 					}
-					if ($attname =~ /(.*)\[.*\]/)    # array attribute
+
+					# If the C name ends with '[]' or '[digits]', we have
+					# an array type, so we discard that from the name and
+					# prepend '_' to the type.
+					if ($attname =~ /(\w+)\[\d*\]/)
 					{
 						$attname = $1;
-						$atttype .= '[]';
+						$atttype = '_' . $atttype;
 					}

 					$column{type} = $atttype;
diff --git a/src/backend/catalog/genbki.pl b/src/backend/catalog/genbki.pl
index f937a37..f6adbe7 100644
--- a/src/backend/catalog/genbki.pl
+++ b/src/backend/catalog/genbki.pl
@@ -350,7 +350,7 @@ EOM

 			# Replace OID synonyms with OIDs per the appropriate lookup rule.
 			#
-			# If the column type is oidvector or oid[], we have to replace
+			# If the column type is oidvector or _oid, we have to replace
 			# each element of the array as per the lookup rule.
 			if ($column->{lookup})
 			{
@@ -368,7 +368,7 @@ EOM
 											  \%bki_values, @lookupnames);
 					$bki_values{$attname} = join(' ', @lookupoids);
 				}
-				elsif ($atttype eq 'oid[]')
+				elsif ($atttype eq '_oid')
 				{
 					if ($bki_values{$attname} ne '_null_')
 					{
@@ -597,10 +597,6 @@ sub morph_row_for_pgattr

 	$row->{attname} = $attname;

-	# Adjust type name for arrays: foo[] becomes _foo, so we can look it up in
-	# pg_type
-	$atttype = '_' . $1 if $atttype =~ /(.+)\[\]$/;
-
 	# Copy the type data from pg_type, and add some type-dependent items
 	my $type = $types{$atttype};

diff --git a/src/include/bootstrap/bootstrap.h b/src/include/bootstrap/bootstrap.h
index 4f41294..7856669 100644
--- a/src/include/bootstrap/bootstrap.h
+++ b/src/include/bootstrap/bootstrap.h
@@ -44,8 +44,6 @@ extern void InsertOneTuple(Oid objectid);
 extern void InsertOneValue(char *value, int i);
 extern void InsertOneNull(int i);

-extern char *MapArrayTypeName(const char *s);
-
 extern void index_register(Oid heap, Oid ind, IndexInfo *indexInfo);
 extern void build_indices(void);

-- 
2.7.4