1 files changed, 47 insertions, 0 deletions

diff --git a/src/backend/postmaster/postmaster.c b/src/backend/postmaster/postmaster.c
index 1bb3138a03a..000524dcb94 100644
--- a/src/backend/postmaster/postmaster.c
+++ b/src/backend/postmaster/postmaster.c
@@ -370,6 +370,7 @@ static DNSServiceRef bonjour_sdref = NULL;
 /*
  * postmaster.c - function prototypes
  */
+static void CloseServerPorts(int status, Datum arg);
 static void unlink_external_pid_file(int status, Datum arg);
 static void getInstallationPaths(const char *argv0);
 static void checkDataDir(void);
@@ -900,6 +901,11 @@ PostmasterMain(int argc, char *argv[])
 	 * interlock (thanks to whoever decided to put socket files in /tmp :-().
 	 * For the same reason, it's best to grab the TCP socket(s) before the
 	 * Unix socket(s).
+	 *
+	 * Also note that this internally sets up the on_proc_exit function that
+	 * is responsible for removing both data directory and socket lockfiles;
+	 * so it must happen before opening sockets so that at exit, the socket
+	 * lockfiles go away after CloseServerPorts runs.
 	 */
 	CreateDataDirLockFile(true);
 
@@ -924,10 +930,15 @@ PostmasterMain(int argc, char *argv[])
 
 	/*
 	 * Establish input sockets.
+	 *
+	 * First, mark them all closed, and set up an on_proc_exit function that's
+	 * charged with closing the sockets again at postmaster shutdown.
 	 */
 	for (i = 0; i < MAXLISTEN; i++)
 		ListenSocket[i] = PGINVALID_SOCKET;
 
+	on_proc_exit(CloseServerPorts, 0);
+
 	if (ListenAddresses)
 	{
 		char	   *rawstring;
@@ -1272,6 +1283,42 @@ PostmasterMain(int argc, char *argv[])
 
 
 /*
+ * on_proc_exit callback to close server's listen sockets
+ */
+static void
+CloseServerPorts(int status, Datum arg)
+{
+	int			i;
+
+	/*
+	 * First, explicitly close all the socket FDs.  We used to just let this
+	 * happen implicitly at postmaster exit, but it's better to close them
+	 * before we remove the postmaster.pid lockfile; otherwise there's a race
+	 * condition if a new postmaster wants to re-use the TCP port number.
+	 */
+	for (i = 0; i < MAXLISTEN; i++)
+	{
+		if (ListenSocket[i] != PGINVALID_SOCKET)
+		{
+			StreamClose(ListenSocket[i]);
+			ListenSocket[i] = PGINVALID_SOCKET;
+		}
+	}
+
+	/*
+	 * Next, remove any filesystem entries for Unix sockets.  To avoid race
+	 * conditions against incoming postmasters, this must happen after closing
+	 * the sockets and before removing lock files.
+	 */
+	RemoveSocketFiles();
+
+	/*
+	 * We don't do anything about socket lock files here; those will be
+	 * removed in a later on_proc_exit callback.
+	 */
+}
+
+/*
  * on_proc_exit callback to delete external_pid_file
  */
 static void