From: Willy Tarreau <w@1wt.eu>
Date: Wed, 3 Oct 2012 19:12:16 +0000 (+0200)
Subject: MEDIUM: connection: make it possible for data->wake to return an error
X-Git-Tag: v1.5-dev13~212
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=2396c1c4a24052e34af0e2b165cf86deeef069aa;p=thirdparty%2Fhaproxy.git

MEDIUM: connection: make it possible for data->wake to return an error

Just like ->init(), ->wake() may now be used to return an error and
abort the connection. Currently this is not used but will be with
embryonic sessions.
---

diff --git a/include/types/connection.h b/include/types/connection.h
index 44fdb0d6c8..3219309dbb 100644
--- a/include/types/connection.h
+++ b/include/types/connection.h
@@ -180,12 +180,13 @@ struct xprt_ops {
  * at the transport layer, which can be a connection opening/close, or any
  * data movement. The <init> callback may be called by the connection handler
  * at the end of a transport handshake, when it is about to transfer data and
- * the data layer is not ready yet.
+ * the data layer is not ready yet. Both <wake> and <init> may abort a connection
+ * by returning < 0.
  */
 struct data_cb {
 	void (*recv)(struct connection *conn);  /* data-layer recv callback */
 	void (*send)(struct connection *conn);  /* data-layer send callback */
-	void (*wake)(struct connection *conn);  /* data-layer callback to report activity */
+	int  (*wake)(struct connection *conn);  /* data-layer callback to report activity */
 	int  (*init)(struct connection *conn);  /* data-layer initialization */
 };
 
diff --git a/src/connection.c b/src/connection.c
index 949e9ccd3e..e156366f2b 100644
--- a/src/connection.c
+++ b/src/connection.c
@@ -123,8 +123,14 @@ int conn_fd_handler(int fd)
 		return 0;
 	}
 
-	if ((conn->flags & CO_FL_WAKE_DATA) && ((conn->flags ^ flags) & CO_FL_CONN_STATE))
-		conn->data->wake(conn);
+	/* The wake callback may be used to process a critical error and abort the
+	 * connection. If so, we don't want to go further as the connection will
+	 * have been released and the FD destroyed.
+	 */
+	if ((conn->flags & CO_FL_WAKE_DATA) &&
+	    ((conn->flags ^ flags) & CO_FL_CONN_STATE) &&
+	    conn->data->wake(conn) < 0)
+		return 0;
 
 	/* Last check, verify if the connection just established */
 	if (unlikely(!(conn->flags & (CO_FL_WAIT_L4_CONN | CO_FL_WAIT_L6_CONN | CO_FL_CONNECTED))))
diff --git a/src/stream_interface.c b/src/stream_interface.c
index 83e085920c..8bc5bbbb25 100644
--- a/src/stream_interface.c
+++ b/src/stream_interface.c
@@ -46,7 +46,7 @@ static void stream_int_chk_rcv_conn(struct stream_interface *si);
 static void stream_int_chk_snd_conn(struct stream_interface *si);
 static void si_conn_recv_cb(struct connection *conn);
 static void si_conn_send_cb(struct connection *conn);
-static void si_conn_wake_cb(struct connection *conn);
+static int si_conn_wake_cb(struct connection *conn);
 
 /* stream-interface operations for embedded tasks */
 struct si_ops si_embedded_ops = {
@@ -561,9 +561,9 @@ int conn_si_send_proxy(struct connection *conn, unsigned int flag)
  * the update function in that it is designed to be called by lower layers after I/O
  * events have been completed. It will also try to wake the associated task up if
  * an important event requires special handling. It relies on the connection handler
- * to commit any polling updates.
+ * to commit any polling updates. The function always returns 0.
  */
-static void si_conn_wake_cb(struct connection *conn)
+static int si_conn_wake_cb(struct connection *conn)
 {
 	struct stream_interface *si = conn->owner;
 
@@ -659,6 +659,7 @@ static void si_conn_wake_cb(struct connection *conn)
 	}
 	if (si->ib->flags & CF_READ_ACTIVITY)
 		si->ib->flags &= ~CF_READ_DONTWAIT;
+	return 0;
 }
 
 /*