From: Stefan Metzmacher <metze@samba.org>
Date: Wed, 26 Feb 2020 12:36:05 +0000 (+0100)
Subject: s3:lib: avoid calling async_connect_send() again and again in open_socket_out*()
X-Git-Tag: ldb-2.2.0~1583
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=a26be7eeedc4995ea1a99f4bbb6ce8beaafda012;p=thirdparty%2Fsamba.git

s3:lib: avoid calling async_connect_send() again and again in open_socket_out*()

There's really no need to do that!

Once connect() is called and returned EINPROGRESS, the kernel
knowns what to do and reports any state change via
TEVENT_FD_READ or TEVENT_FD_WRITE.
The actual success or failure is available via
getsockopt(.., SOL_SOCKET, SO_ERROR, ...).

Before this commit we called connect() (via async_connect_send()) again
and again until we reached the final caller provided timeout,
even if the kernel already found out that the destination is
unreachable.

Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>
---

diff --git a/source3/lib/util_sock.c b/source3/lib/util_sock.c
index 0649873a9f6..e48cdb07ca9 100644
--- a/source3/lib/util_sock.c
+++ b/source3/lib/util_sock.c
@@ -417,7 +417,6 @@ struct open_socket_out_state {
 	struct sockaddr_storage ss;
 	socklen_t salen;
 	uint16_t port;
-	int wait_usec;
 	struct tevent_req *connect_subreq;
 };
 
@@ -471,7 +470,6 @@ struct tevent_req *open_socket_out_send(TALLOC_CTX *mem_ctx,
 	state->ev = ev;
 	state->ss = *pss;
 	state->port = port;
-	state->wait_usec = 10000;
 	state->salen = -1;
 
 	state->fd = socket(state->ss.ss_family, SOCK_STREAM, 0);
@@ -522,12 +520,6 @@ struct tevent_req *open_socket_out_send(TALLOC_CTX *mem_ctx,
 	if (tevent_req_nomem(state->connect_subreq, NULL)) {
 		return tevent_req_post(req, ev);
 	}
-	if (!tevent_req_set_endtime(
-		    state->connect_subreq, state->ev,
-		    timeval_current_ofs(0, state->wait_usec))) {
-		tevent_req_oom(req);
-		return tevent_req_post(req, ev);
-	}
 	tevent_req_set_callback(state->connect_subreq,
 				open_socket_out_connected, req);
 	return req;
@@ -550,46 +542,6 @@ static void open_socket_out_connected(struct tevent_req *subreq)
 		return;
 	}
 
-	if (
-#ifdef ETIMEDOUT
-		(sys_errno == ETIMEDOUT) ||
-#endif
-		(sys_errno == EINPROGRESS) ||
-		(sys_errno == EALREADY) ||
-		(sys_errno == EAGAIN)) {
-
-		/*
-		 * retry
-		 */
-
-		if (state->wait_usec < 250000) {
-			state->wait_usec *= 1.5;
-		}
-
-		subreq = async_connect_send(state, state->ev, state->fd,
-					    (struct sockaddr *)&state->ss,
-					    state->salen, NULL, NULL, NULL);
-		if (tevent_req_nomem(subreq, req)) {
-			return;
-		}
-		if (!tevent_req_set_endtime(
-			    subreq, state->ev,
-			    timeval_current_ofs_usec(state->wait_usec))) {
-			return;
-		}
-		state->connect_subreq = subreq;
-		tevent_req_set_callback(subreq, open_socket_out_connected, req);
-		return;
-	}
-
-#ifdef EISCONN
-	if (sys_errno == EISCONN) {
-		tevent_req_done(req);
-		return;
-	}
-#endif
-
-	/* real error */
 	tevent_req_nterror(req, map_nt_error_from_unix(sys_errno));
 }