From: Stefan Metzmacher <metze@samba.org>
Date: Fri, 16 Feb 2018 14:02:42 +0000 (+0100)
Subject: winbind: use tevent_queue_wait_send/recv in wb_child_request_*()
X-Git-Tag: ldb-1.3.2~55
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=d29dda141e08af42c535e8718226f95c45aadab8;p=thirdparty%2Fsamba.git

winbind: use tevent_queue_wait_send/recv in wb_child_request_*()

We need a way to keep the child->queue blocked without relying on
the current 'req' (wb_child_request_state).

The next commit will make use of this.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=13290

Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Volker Lendecke <vl@samba.org>
---

diff --git a/source3/winbindd/winbindd_dual.c b/source3/winbindd/winbindd_dual.c
index 7fb5aa899e4..fa5b5b0589e 100644
--- a/source3/winbindd/winbindd_dual.c
+++ b/source3/winbindd/winbindd_dual.c
@@ -119,6 +119,7 @@ static NTSTATUS child_write_response(int sock, struct winbindd_response *wrsp)
 
 struct wb_child_request_state {
 	struct tevent_context *ev;
+	struct tevent_req *queue_subreq;
 	struct tevent_req *subreq;
 	struct winbindd_child *child;
 	struct winbindd_request *request;
@@ -127,8 +128,7 @@ struct wb_child_request_state {
 
 static bool fork_domain_child(struct winbindd_child *child);
 
-static void wb_child_request_trigger(struct tevent_req *req,
-					    void *private_data);
+static void wb_child_request_waited(struct tevent_req *subreq);
 static void wb_child_request_done(struct tevent_req *subreq);
 
 static void wb_child_request_cleanup(struct tevent_req *req,
@@ -141,6 +141,7 @@ struct tevent_req *wb_child_request_send(TALLOC_CTX *mem_ctx,
 {
 	struct tevent_req *req;
 	struct wb_child_request_state *state;
+	struct tevent_req *subreq;
 
 	req = tevent_req_create(mem_ctx, &state,
 				struct wb_child_request_state);
@@ -152,23 +153,36 @@ struct tevent_req *wb_child_request_send(TALLOC_CTX *mem_ctx,
 	state->child = child;
 	state->request = request;
 
-	if (!tevent_queue_add(child->queue, ev, req,
-			      wb_child_request_trigger, NULL)) {
-		tevent_req_oom(req);
+	subreq = tevent_queue_wait_send(state, ev, child->queue);
+	if (tevent_req_nomem(subreq, req)) {
 		return tevent_req_post(req, ev);
 	}
+	tevent_req_set_callback(subreq, wb_child_request_waited, req);
+	state->queue_subreq = subreq;
 
 	tevent_req_set_cleanup_fn(req, wb_child_request_cleanup);
 
 	return req;
 }
 
-static void wb_child_request_trigger(struct tevent_req *req,
-				     void *private_data)
+static void wb_child_request_waited(struct tevent_req *subreq)
 {
+	struct tevent_req *req = tevent_req_callback_data(
+		subreq, struct tevent_req);
 	struct wb_child_request_state *state = tevent_req_data(
 		req, struct wb_child_request_state);
-	struct tevent_req *subreq;
+	bool ok;
+
+	ok = tevent_queue_wait_recv(subreq);
+	if (!ok) {
+		tevent_req_oom(req);
+		return;
+	}
+	/*
+	 * We need to keep state->queue_subreq
+	 * in order to block the queue.
+	 */
+	subreq = NULL;
 
 	if ((state->child->sock == -1) && (!fork_domain_child(state->child))) {
 		tevent_req_error(req, errno);
@@ -231,6 +245,7 @@ static void wb_child_request_cleanup(struct tevent_req *req,
 	}
 
 	TALLOC_FREE(state->subreq);
+	TALLOC_FREE(state->queue_subreq);
 
 	if (req_state == TEVENT_REQ_DONE) {
 		/* transmitted request and got response */