Move genbki.pl's find_defined_symbol to Catalog.pm.

Will be used in Gen_fmgrtab.pl in a followup commit.

src/backend/catalog/Catalog.pm

@@ -19,7 +19,7 @@ use warnings;
 require Exporter;
 our @ISA       = qw(Exporter);
 our @EXPORT    = ();
-our @EXPORT_OK = qw(Catalogs SplitDataLine RenameTempFile);
+our @EXPORT_OK = qw(Catalogs SplitDataLine RenameTempFile FindDefinedSymbol);
 
 # Call this function with an array of names of header files to parse.
 # Returns a nested data structure describing the data in the headers.
@@ -252,6 +252,39 @@ sub RenameTempFile
 	rename($temp_name, $final_name) || die "rename: $temp_name: $!";
 }
 
+
+# Find a symbol defined in a particular header file and extract the value.
+#
+# The include path has to be passed as a reference to an array.
+sub FindDefinedSymbol
+{
+	my ($catalog_header, $include_path, $symbol) = @_;
+
+	for my $path (@$include_path)
+	{
+
+		# Make sure include path ends in a slash.
+		if (substr($path, -1) ne '/')
+		{
+			$path .= '/';
+		}
+		my $file = $path . $catalog_header;
+		next if !-f $file;
+		open(my $find_defined_symbol, '<', $file) || die "$file: $!";
+		while (<$find_defined_symbol>)
+		{
+			if (/^#define\s+\Q$symbol\E\s+(\S+)/)
+			{
+				return $1;
+			}
+		}
+		close $find_defined_symbol;
+		die "$file: no definition found for $symbol\n";
+	}
+	die "$catalog_header: not found in any include directory\n";
+}
+
+
 # verify the number of fields in the passed-in DATA line
 sub check_natts
 {

src/backend/catalog/genbki.pl

@@ -87,9 +87,11 @@ open my $shdescr, '>', $shdescrfile . $tmpext
 # NB: make sure that the files used here are known to be part of the .bki
 # file's dependencies by src/backend/catalog/Makefile.
 my $BOOTSTRAP_SUPERUSERID =
-  find_defined_symbol('pg_authid.h', 'BOOTSTRAP_SUPERUSERID');
+  Catalog::FindDefinedSymbol('pg_authid.h', \@include_path,
+							 'BOOTSTRAP_SUPERUSERID');
 my $PG_CATALOG_NAMESPACE =
-  find_defined_symbol('pg_namespace.h', 'PG_CATALOG_NAMESPACE');
+  Catalog::FindDefinedSymbol('pg_namespace.h', \@include_path,
+							 'PG_CATALOG_NAMESPACE');
 
 # Read all the input header files into internal data structures
 my $catalogs = Catalog::Catalogs(@input_files);
@@ -500,34 +502,6 @@ sub emit_schemapg_row
 	return $row;
 }
 
-# Find a symbol defined in a particular header file and extract the value.
-sub find_defined_symbol
-{
-	my ($catalog_header, $symbol) = @_;
-	for my $path (@include_path)
-	{
-
-		# Make sure include path ends in a slash.
-		if (substr($path, -1) ne '/')
-		{
-			$path .= '/';
-		}
-		my $file = $path . $catalog_header;
-		next if !-f $file;
-		open(my $find_defined_symbol, '<', $file) || die "$file: $!";
-		while (<$find_defined_symbol>)
-		{
-			if (/^#define\s+\Q$symbol\E\s+(\S+)/)
-			{
-				return $1;
-			}
-		}
-		close $find_defined_symbol;
-		die "$file: no definition found for $symbol\n";
-	}
-	die "$catalog_header: not found in any include directory\n";
-}
-
 sub usage
 {
 	die <<EOM;