Change the built-in default socket directory to be /var/run/postgresql.

For backwards compatibility with (probably non-libpq-based) clients that

might still expect to find the socket in /tmp, also create a socket in

/tmp.  This is to resolve communication problems with clients operating

under systemd's PrivateTmp environment, which won't be using the same

global /tmp directory as the server; see bug #825448.

Note that we apply the socket directory change at the level of the

hard-wired defaults in the C code, not by just twiddling the setting in

postgresql.conf.sample; this is so that the change will take effect on

server package update, without requiring any existing postgresql.conf

to be updated.  (Of course, a user who dislikes this behavior can still

override it via postgresql.conf.)

This patch must be applied after postgresql-multi-sockets.patch, at

least until 9.3 when that will be part of the upstream package.

diff -Naur postgresql-9.2.2.sockets/contrib/pg_upgrade/test.sh postgresql-9.2.2/contrib/pg_upgrade/test.sh

--- postgresql-9.2.2.sockets/contrib/pg_upgrade/test.sh	2013-01-03 17:33:45.581567466 -0500

+++ postgresql-9.2.2/contrib/pg_upgrade/test.sh	2013-01-03 17:40:22.923364917 -0500

@@ -78,6 +78,12 @@

 rm -rf "$logdir"

 mkdir "$logdir"

+# we want the Unix sockets in $temp_root

+PGHOST=$temp_root

+export PGHOST

+

+POSTMASTER_OPTS="$POSTMASTER_OPTS -c unix_socket_directories='$PGHOST'"

+

 # enable echo so the user can see what is being executed

 set -x

diff -Naur postgresql-9.2.2.sockets/src/backend/utils/misc/guc.c postgresql-9.2.2/src/backend/utils/misc/guc.c

--- postgresql-9.2.2.sockets/src/backend/utils/misc/guc.c	2013-01-03 17:37:56.632977951 -0500

+++ postgresql-9.2.2/src/backend/utils/misc/guc.c	2013-01-03 17:38:30.183271588 -0500

@@ -2901,7 +2901,7 @@

 		},

 		&Unix_socket_directories,

 #ifdef HAVE_UNIX_SOCKETS

-		DEFAULT_PGSOCKET_DIR,

+		DEFAULT_PGSOCKET_DIR ", /tmp",

 #else

 		"",

 #endif

diff -Naur postgresql-9.2.2.sockets/src/bin/initdb/initdb.c postgresql-9.2.2/src/bin/initdb/initdb.c

--- postgresql-9.2.2.sockets/src/bin/initdb/initdb.c	2013-01-03 17:37:56.633977974 -0500

+++ postgresql-9.2.2/src/bin/initdb/initdb.c	2013-01-03 17:38:30.185271611 -0500

@@ -1007,7 +1007,7 @@

 #ifdef HAVE_UNIX_SOCKETS

 	snprintf(repltok, sizeof(repltok), "#unix_socket_directories = '%s'",

-			 DEFAULT_PGSOCKET_DIR);

+			 DEFAULT_PGSOCKET_DIR ", /tmp");

 #else

 	snprintf(repltok, sizeof(repltok), "#unix_socket_directories = ''");

 #endif

diff -Naur postgresql-9.2.2.sockets/src/include/pg_config_manual.h postgresql-9.2.2/src/include/pg_config_manual.h

--- postgresql-9.2.2.sockets/src/include/pg_config_manual.h	2012-12-03 15:16:10.000000000 -0500

+++ postgresql-9.2.2/src/include/pg_config_manual.h	2013-01-03 17:38:30.185271611 -0500

@@ -144,7 +144,7 @@

  * here's where to twiddle it.  You can also override this at runtime

  * with the postmaster's -k switch.

  */

-#define DEFAULT_PGSOCKET_DIR  "/tmp"

+#define DEFAULT_PGSOCKET_DIR  "/var/run/postgresql"

 /*

  * The random() function is expected to yield values between 0 and

diff -Naur postgresql-9.2.2.sockets/src/test/regress/pg_regress.c postgresql-9.2.2/src/test/regress/pg_regress.c

--- postgresql-9.2.2.sockets/src/test/regress/pg_regress.c	2012-12-03 15:16:10.000000000 -0500

+++ postgresql-9.2.2/src/test/regress/pg_regress.c	2013-01-03 17:38:30.186271622 -0500

@@ -772,7 +772,7 @@

 		if (hostname != NULL)

 			doputenv("PGHOST", hostname);

 		else

-			unsetenv("PGHOST");

+			doputenv("PGHOST", "/tmp");

 		unsetenv("PGHOSTADDR");

 		if (port != -1)

 		{

@@ -2246,7 +2246,7 @@

 		 */

 		header(_("starting postmaster"));

 		snprintf(buf, sizeof(buf),

-				 SYSTEMQUOTE "\"%s/postgres\" -D \"%s/data\" -F%s -c \"listen_addresses=%s\" > \"%s/log/postmaster.log\" 2>&1" SYSTEMQUOTE,

+				 SYSTEMQUOTE "\"%s/postgres\" -D \"%s/data\" -F%s -c \"listen_addresses=%s\" -c \"unix_socket_directories=/tmp\" > \"%s/log/postmaster.log\" 2>&1" SYSTEMQUOTE,

 				 bindir, temp_install,

 				 debug ? " -d 5" : "",

 				 hostname ? hostname : "",