From 0caeda53d37740d18b38e6d37d0ecef8c6336820 Mon Sep 17 00:00:00 2001
From: Andrew Tridgell <tridge@samba.org>
Date: Fri, 29 Oct 2004 07:00:14 +0000
Subject: r3356: in the standard process model we need to make sure we close
 all listening sockets after the fork to prevent the child still listening on
 incoming requests.

I have also added an optimisation where we use dup()/close() to lower
the file descriptor number of the new socket to the lowest possible
after closing our listening sockets. This keeps the max fd num passed
to select() low, which makes a difference to the speed of select().
(This used to be commit f2a9bbc317ba86ebe87c3ca27a3a0192de91014d)
---
 source4/lib/socket/socket.c     | 22 ++++++++++++++++++++++
 source4/smbd/process_standard.c |  9 +++++++--
 source4/smbd/service.c          | 21 +++++++++++++++++++++
 3 files changed, 50 insertions(+), 2 deletions(-)

(limited to 'source4')

diff --git a/source4/lib/socket/socket.c b/source4/lib/socket/socket.c
index dbbae5ea7e..892695f6eb 100644
--- a/source4/lib/socket/socket.c
+++ b/source4/lib/socket/socket.c
@@ -260,6 +260,28 @@ int socket_get_fd(struct socket_context *sock)
 	return sock->ops->get_fd(sock);
 }
 
+/*
+  call dup() on a socket, and close the old fd. This is used to change
+  the fd to the lowest available number, to make select() more
+  efficient (select speed depends on the maxiumum fd number passed to
+  it)
+*/
+NTSTATUS socket_dup(struct socket_context *sock)
+{
+	int fd;
+	if (sock->fd == -1) {
+		return NT_STATUS_INVALID_HANDLE;
+	}
+	fd = dup(sock->fd);
+	if (fd == -1) {
+		return map_nt_error_from_unix(errno);
+	}
+	close(sock->fd);
+	sock->fd = fd;
+	return NT_STATUS_OK;
+	
+}
+
 const struct socket_ops *socket_getops_byname(const char *name, enum socket_type type)
 {
 	if (strcmp("ip", name) == 0 || 
diff --git a/source4/smbd/process_standard.c b/source4/smbd/process_standard.c
index 106be77925..9b5547ce54 100644
--- a/source4/smbd/process_standard.c
+++ b/source4/smbd/process_standard.c
@@ -34,7 +34,8 @@ static void standard_model_startup(void)
 /*
   called when a listening socket becomes readable
 */
-static void standard_accept_connection(struct event_context *ev, struct fd_event *srv_fde, time_t t, uint16_t flags)
+static void standard_accept_connection(struct event_context *ev, struct fd_event *srv_fde,
+				       time_t t, uint16_t flags)
 {
 	NTSTATUS status;
 	struct socket_context *sock;
@@ -63,7 +64,11 @@ static void standard_accept_connection(struct event_context *ev, struct fd_event
 	/* Child code ... */
 
 	/* close all the listening sockets */
-	event_remove_fd_all_handler(ev, standard_accept_connection);
+	service_close_listening_sockets(server_socket->service->srv_ctx);
+
+	/* we don't care if the dup fails, as its only a select()
+	   speed optimisation */
+	socket_dup(sock);
 			
 	/* tdb needs special fork handling */
 	if (tdb_reopen_all() == -1) {
diff --git a/source4/smbd/service.c b/source4/smbd/service.c
index ac46992261..ca5f5e7531 100644
--- a/source4/smbd/service.c
+++ b/source4/smbd/service.c
@@ -77,6 +77,8 @@ struct server_context *server_service_startup(const char *model)
 		
 		/* TODO: service_init() should return a result */
 		service->ops->service_init(service, model_ops);
+
+		DLIST_ADD(srv_ctx->service_list, service);
 	}
 
 	return srv_ctx;
@@ -328,3 +330,22 @@ BOOL server_service_init(void)
 	DEBUG(3,("SERVER SERVICE subsystem version %d initialised\n", SERVER_SERVICE_VERSION));
 	return True;
 }
+
+
+/*
+  close all listening sockets. This is called by process models that fork, to 
+  ensure that the listen sockets from the parent are closed
+*/
+void service_close_listening_sockets(struct server_context *srv_ctx)
+{
+	struct server_service *svc;
+	for (svc=srv_ctx->service_list;svc;svc=svc->next) {
+		struct server_socket *sock;
+		for (sock=svc->socket_list;sock;sock=sock->next) {
+			event_remove_fd(sock->event.ctx, sock->event.fde);
+			sock->event.fde = NULL;
+			socket_destroy(sock->socket);
+			sock->socket = NULL;
+		}
+	}
+}
-- 
cgit