From 60711e8bb25371b237835c0f78a64d139589c8c6 Mon Sep 17 00:00:00 2001
From: Kyotaro Horiguchi <horiguchi.kyotaro@lab.ntt.co.jp>
Date: Tue, 27 Nov 2018 14:42:12 +0900
Subject: [PATCH 5/7] Remove the GUC stats_temp_directory

The guc used to specifie the directory to store temporary statistics
files. It is no longer needed by the stats collector but still used by
the programs in bin and contirb, and maybe other extensions. Thus this
patch removes the GUC but some backing variables and macro definitions
are left alone for backward comptibility.
---
 src/backend/postmaster/pgstat.c               | 12 +++-----
 src/backend/replication/basebackup.c          | 13 ++-------
 src/backend/utils/misc/guc.c                  | 41 ---------------------------
 src/backend/utils/misc/postgresql.conf.sample |  1 -
 src/include/pgstat.h                          |  5 +++-
 5 files changed, 11 insertions(+), 61 deletions(-)

diff --git a/src/backend/postmaster/pgstat.c b/src/backend/postmaster/pgstat.c
index a97fbae7a8..78f0bbb558 100644
--- a/src/backend/postmaster/pgstat.c
+++ b/src/backend/postmaster/pgstat.c
@@ -89,15 +89,11 @@ bool		pgstat_track_counts = false;
 int			pgstat_track_functions = TRACK_FUNC_OFF;
 int			pgstat_track_activity_query_size = 1024;
 
-/* ----------
- * Built from GUC parameter
- * ----------
+/*
+ * This was a GUC parameter and no longer used in this file. But left alone
+ * just for backward comptibility for extensions, having the default value.
  */
-char	   *pgstat_stat_directory = NULL;
-
-/* No longer used, but will be removed with GUC */
-char	   *pgstat_stat_filename = NULL;
-char	   *pgstat_stat_tmpname = NULL;
+char	   *pgstat_stat_directory = PG_STAT_TMP_DIR;
 
 /* Shared stats bootstrap infomation */
 typedef struct StatsShmemStruct {
diff --git a/src/backend/replication/basebackup.c b/src/backend/replication/basebackup.c
index def6c03dd0..58ba33e822 100644
--- a/src/backend/replication/basebackup.c
+++ b/src/backend/replication/basebackup.c
@@ -230,11 +230,8 @@ perform_base_backup(basebackup_options *opt)
 	TimeLineID	endtli;
 	StringInfo	labelfile;
 	StringInfo	tblspc_map_file = NULL;
-	int			datadirpathlen;
 	List	   *tablespaces = NIL;
 
-	datadirpathlen = strlen(DataDir);
-
 	backup_started_in_recovery = RecoveryInProgress();
 
 	labelfile = makeStringInfo();
@@ -265,13 +262,9 @@ perform_base_backup(basebackup_options *opt)
 		 * Calculate the relative path of temporary statistics directory in
 		 * order to skip the files which are located in that directory later.
 		 */
-		if (is_absolute_path(pgstat_stat_directory) &&
-			strncmp(pgstat_stat_directory, DataDir, datadirpathlen) == 0)
-			statrelpath = psprintf("./%s", pgstat_stat_directory + datadirpathlen + 1);
-		else if (strncmp(pgstat_stat_directory, "./", 2) != 0)
-			statrelpath = psprintf("./%s", pgstat_stat_directory);
-		else
-			statrelpath = pgstat_stat_directory;
+
+		Assert(strchr(PG_STAT_TMP_DIR, '/') == NULL);
+		statrelpath = psprintf("./%s", PG_STAT_TMP_DIR);
 
 		/* Add a node for the base directory at the end */
 		ti = palloc0(sizeof(tablespaceinfo));
diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index c216ed0922..099afd0724 100644
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -189,7 +189,6 @@ static bool check_autovacuum_max_workers(int *newval, void **extra, GucSource so
 static bool check_autovacuum_work_mem(int *newval, void **extra, GucSource source);
 static bool check_effective_io_concurrency(int *newval, void **extra, GucSource source);
 static void assign_effective_io_concurrency(int newval, void *extra);
-static void assign_pgstat_temp_directory(const char *newval, void *extra);
 static bool check_application_name(char **newval, void **extra, GucSource source);
 static void assign_application_name(const char *newval, void *extra);
 static bool check_cluster_name(char **newval, void **extra, GucSource source);
@@ -3973,17 +3972,6 @@ static struct config_string ConfigureNamesString[] =
 		NULL, NULL, NULL
 	},
 
-	{
-		{"stats_temp_directory", PGC_SIGHUP, STATS_COLLECTOR,
-			gettext_noop("Writes temporary statistics files to the specified directory."),
-			NULL,
-			GUC_SUPERUSER_ONLY
-		},
-		&pgstat_temp_directory,
-		PG_STAT_TMP_DIR,
-		check_canonical_path, assign_pgstat_temp_directory, NULL
-	},
-
 	{
 		{"synchronous_standby_names", PGC_SIGHUP, REPLICATION_MASTER,
 			gettext_noop("Number of synchronous standbys and list of names of potential synchronous ones."),
@@ -10966,35 +10954,6 @@ assign_effective_io_concurrency(int newval, void *extra)
 #endif							/* USE_PREFETCH */
 }
 
-static void
-assign_pgstat_temp_directory(const char *newval, void *extra)
-{
-	/* check_canonical_path already canonicalized newval for us */
-	char	   *dname;
-	char	   *tname;
-	char	   *fname;
-
-	/* directory */
-	dname = guc_malloc(ERROR, strlen(newval) + 1);	/* runtime dir */
-	sprintf(dname, "%s", newval);
-
-	/* global stats */
-	tname = guc_malloc(ERROR, strlen(newval) + 12); /* /global.tmp */
-	sprintf(tname, "%s/global.tmp", newval);
-	fname = guc_malloc(ERROR, strlen(newval) + 13); /* /global.stat */
-	sprintf(fname, "%s/global.stat", newval);
-
-	if (pgstat_stat_directory)
-		free(pgstat_stat_directory);
-	pgstat_stat_directory = dname;
-	if (pgstat_stat_tmpname)
-		free(pgstat_stat_tmpname);
-	pgstat_stat_tmpname = tname;
-	if (pgstat_stat_filename)
-		free(pgstat_stat_filename);
-	pgstat_stat_filename = fname;
-}
-
 static bool
 check_application_name(char **newval, void **extra, GucSource source)
 {
diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample
index a21865a77f..a65656a4d2 100644
--- a/src/backend/utils/misc/postgresql.conf.sample
+++ b/src/backend/utils/misc/postgresql.conf.sample
@@ -552,7 +552,6 @@
 #track_io_timing = off
 #track_functions = none			# none, pl, all
 #track_activity_query_size = 1024	# (change requires restart)
-#stats_temp_directory = 'pg_stat_tmp'
 
 
 # - Monitoring -
diff --git a/src/include/pgstat.h b/src/include/pgstat.h
index 1ad77fb20f..d10ea5389b 100644
--- a/src/include/pgstat.h
+++ b/src/include/pgstat.h
@@ -31,7 +31,10 @@
 #define PGSTAT_STAT_PERMANENT_FILENAME		"pg_stat/global.stat"
 #define PGSTAT_STAT_PERMANENT_TMPFILE		"pg_stat/global.tmp"
 
-/* Default directory to store temporary statistics data in */
+/*
+ * This used to be the directory to store temporary statistics data in but is
+ * no longer used. Defined here for backward compatibility.
+ */
 #define PG_STAT_TMP_DIR		"pg_stat_tmp"
 
 /* Values for track_functions GUC variable --- order is significant! */
-- 
2.16.3

