Fix scanning of tablespaces.

Commit 60fae02 introduced a whitelist of relation filenames to compare files or
directories to. However, it missed that non-default tablespaces have a
PG_<VER>_<CATNO> directory, that was not considered a relation and skipped, so
pg_checksums would not verify or activate checksums in tablespaces.

Fix this by adopting a proposed patch by Michael Paquier that only checks
proper files for being a relation file, not directories. Also adapt TAP tests
inducing corruption in a table in a non-default tablespace.

pg_checksums.c

@@ -53,6 +53,9 @@ extern char *optarg;
 #define INT64_MODIFIER "l"
 #endif
 
+#define PG_TEMP_FILES_DIR "pgsql_tmp"
+#define PG_TEMP_FILE_PREFIX "pgsql_tmp"
+
 static int64 files = 0;
 static int64 blocks = 0;
 static int64 skippedblocks = 0;
@@ -114,7 +117,6 @@ usage(void)
 	printf(_("Report bugs to https://github.com/credativ/pg_checksums/issues/new.\n"));
 }
 
-
 /*
  * isRelFileName
  *
@@ -464,7 +466,20 @@ scan_directory(const char *basedir, const char *subdir, bool sizeonly)
 		char		fn[MAXPGPATH];
 		struct stat st;
 
-		if (!isRelFileName(de->d_name))
+		if (strcmp(de->d_name, ".") == 0 ||
+			strcmp(de->d_name, "..") == 0)
+			continue;
+
+		/* Skip temporary files */
+		if (strncmp(de->d_name,
+					PG_TEMP_FILE_PREFIX,
+					strlen(PG_TEMP_FILE_PREFIX)) == 0)
+			continue;
+
+		/* Skip temporary folders */
+		if (strncmp(de->d_name,
+					PG_TEMP_FILES_DIR,
+					strlen(PG_TEMP_FILES_DIR)) == 0)
 			continue;
 
 		snprintf(fn, sizeof(fn), "%s/%s", path, de->d_name);
@@ -490,6 +505,13 @@ scan_directory(const char *basedir, const char *subdir, bool sizeonly)
 					   *segmentpath;
 			BlockNumber	segmentno = 0;
 
+			/*
+			 * Only normal relation files can be analyzed.  Note that this
+			 * skips temporary relations.
+			 */
+			if (!isRelFileName(de->d_name))
+				continue;
+
 			/*
 			 * Cut off at the segment boundary (".") to get the segment number
 			 * in order to mix it into the checksum. Then also cut off at the

t/001_checksums.pl

@@ -6,7 +6,7 @@
 use Config;
 use PostgresNode;
 use TestLib;
-use Test::More tests => 44;
+use Test::More tests => 49;
 
 program_help_ok('pg_checksums');
 program_version_ok('pg_checksums');
@@ -80,34 +80,73 @@
 $node->command_ok(['pg_checksums', '-a', '-D', $pgdata],
         'pg_checksums are again activated in offline cluster');
 
+#exit 0;
 $node->start;
 
 $node->command_ok(['pg_checksums', '-c', '-D', $pgdata],
         'pg_checksums can be verified in online cluster');
 
 # create table to corrupt and get their relfilenode
-my $file_corrupt = $node->safe_psql('postgres',
-        q{SELECT a INTO corrupt1 FROM generate_series(1,10000) AS a; ALTER TABLE corrupt1 SET (autovacuum_enabled=false); SELECT pg_relation_filepath('corrupt1')}
+create_corruption($node, 'corrupt1', 'pg_default');
+
+$node->command_checks_all([ 'pg_checksums', '-c', '-D', $pgdata],
+        1,
+        [qr/Bad checksums:  1/s],
+        [qr/checksum verification failed/s],
+        'pg_checksums reports checksum mismatch'
 );
 
-# set page header and block sizes
-my $pageheader_size = 24;
-my $block_size = $node->safe_psql('postgres', 'SHOW block_size;');
+# drop corrupt table again and make sure there is no more corruption
+$node->safe_psql('postgres', 'DROP TABLE corrupt1;');
+$node->command_ok(['pg_checksums', '-c', '-D', $pgdata],
+        'pg_checksums can be verified in online cluster: '.getcwd());
 
-# induce corruption
-$node->stop;
-open my $file, '+<', "$pgdata/$file_corrupt";
-seek($file, $pageheader_size, 0);
-syswrite($file, '\0\0\0\0\0\0\0\0\0');
-close $file;
+
+# create table to corrupt in a non-default tablespace and get their relfilenode
+my $tablespace_dir = getcwd()."/tmp_check/ts_corrupt_dir";
+mkdir ($tablespace_dir);
+$node->safe_psql('postgres', "CREATE TABLESPACE ts_corrupt LOCATION '".$tablespace_dir."';");
+create_corruption($node, 'corrupt2', 'ts_corrupt');
 
 $node->command_checks_all([ 'pg_checksums', '-c', '-D', $pgdata],
         1,
         [qr/Bad checksums:  1/s],
         [qr/checksum verification failed/s],
-        'pg_checksums reports checksum mismatch'
+        'pg_checksums reports checksum mismatch on non-default tablespace'
 );
 
+# drop corrupt table again and make sure there is no more corruption
+$node->safe_psql('postgres', 'DROP TABLE corrupt2;');
+$node->command_ok(['pg_checksums', '-c', '-D', $pgdata],
+        'pg_checksums can be verified in online cluster');
+
+# Utility routine to create a table with corrupted checksums.
+# It stops the node (if running), and starts it again.
+sub create_corruption
+{
+	my $node = shift;
+	my $table = shift;
+	my $tablespace = shift;
+
+	my $query = "SELECT a INTO ".$table." FROM generate_series(1,10000) AS a; ALTER TABLE ".$table." SET (autovacuum_enabled=false), SET TABLESPACE ".$tablespace."; SELECT pg_relation_filepath('".$table."')";
+	my $file_name = $node->safe_psql('postgres', $query);
+
+	# set page header and block sizes
+	my $pageheader_size = 24;
+	my $block_size = $node->safe_psql('postgres', 'SHOW block_size;');
+
+	$node->stop;
+
+	open my $file, '+<', "$pgdata/$file_name";
+	seek($file, $pageheader_size, 0);
+	syswrite($file, '\0\0\0\0\0\0\0\0\0');
+	close $file;
+
+	$node->start;
+
+	return;
+}
+
 # Utility routine to check that pg_checksums is able to detect
 # correctly-named relation files filled with some corrupted data.
 sub fail_corrupt