lib: msg: refactor common connection code from mgmtd

Signed-off-by: Christian Hopps <chopps@labn.net>

1 files changed, 252 insertions, 5 deletions

diff --git a/lib/mgmt_msg.c b/lib/mgmt_msg.c
index e682face9..967606d20 100644
--- a/lib/mgmt_msg.c
+++ b/lib/mgmt_msg.c
@@ -22,7 +22,7 @@
 	} while (0)
 
 #define MGMT_MSG_ERR(ms, fmt, ...)                                             \
-	zlog_err("%s: %s: " fmt, ms->idtag, __func__, ##__VA_ARGS__)
+	zlog_err("%s: %s: " fmt, (ms)->idtag, __func__, ##__VA_ARGS__)
 
 /**
  * Read data from a socket into streams containing 1 or more full msgs headed by
@@ -127,8 +127,8 @@ enum mgmt_msg_rsched mgmt_msg_read(struct mgmt_msg_state *ms, int fd,
  *	true if more to process (so reschedule) else false
  */
 bool mgmt_msg_procbufs(struct mgmt_msg_state *ms,
-		       void (*handle_msg)(uint8_t version, void *user,
-					  uint8_t *msg, size_t msglen),
+		       void (*handle_msg)(uint8_t version, uint8_t *msg,
+					  size_t msglen, void *user),
 		       void *user, bool debug)
 {
 	const char *dbgtag = debug ? ms->idtag : NULL;
@@ -156,9 +156,10 @@ bool mgmt_msg_procbufs(struct mgmt_msg_state *ms,
 			assert(MGMT_MSG_IS_MARKER(mhdr->marker));
 			assert(left >= mhdr->len);
 
-			handle_msg(MGMT_MSG_MARKER_VERSION(mhdr->marker), user,
+			handle_msg(MGMT_MSG_MARKER_VERSION(mhdr->marker),
 				   (uint8_t *)(mhdr + 1),
-				   mhdr->len - sizeof(struct mgmt_msg_hdr));
+				   mhdr->len - sizeof(struct mgmt_msg_hdr),
+				   user);
 			ms->nrxm++;
 			nproc++;
 		}
@@ -402,6 +403,7 @@ size_t mgmt_msg_reset_writes(struct mgmt_msg_state *ms)
 	return nproc;
 }
 
+
 void mgmt_msg_init(struct mgmt_msg_state *ms, size_t max_read_buf,
 		   size_t max_write_buf, size_t max_msg_sz, const char *idtag)
 {
@@ -422,3 +424,248 @@ void mgmt_msg_destroy(struct mgmt_msg_state *ms)
 		stream_free(ms->ins);
 	free(ms->idtag);
 }
+
+/*
+ * Connections
+ */
+
+#define MSG_CONN_DEFAULT_CONN_RETRY_MSEC 250
+#define MSG_CONN_SEND_BUF_SIZE (1u << 16)
+#define MSG_CONN_RECV_BUF_SIZE (1u << 16)
+
+static void msg_client_sched_connect(struct msg_client *client,
+				     unsigned long msec);
+
+static void msg_conn_sched_proc_msgs(struct msg_conn *conn);
+static void msg_conn_sched_read(struct msg_conn *conn);
+static void msg_conn_sched_write(struct msg_conn *conn);
+
+static void msg_conn_write(struct event *thread)
+{
+	struct msg_conn *conn = EVENT_ARG(thread);
+	enum mgmt_msg_wsched rv;
+
+	rv = mgmt_msg_write(&conn->mstate, conn->fd, conn->debug);
+	if (rv == MSW_SCHED_STREAM)
+		msg_conn_sched_write(conn);
+	else if (rv == MSW_DISCONNECT)
+		msg_conn_disconnect(conn, conn->is_client);
+	else
+		assert(rv == MSW_SCHED_NONE);
+}
+
+static void msg_conn_read(struct event *thread)
+{
+	struct msg_conn *conn = EVENT_ARG(thread);
+	enum mgmt_msg_rsched rv;
+
+	rv = mgmt_msg_read(&conn->mstate, conn->fd, conn->debug);
+	if (rv == MSR_DISCONNECT) {
+		msg_conn_disconnect(conn, conn->is_client);
+		return;
+	}
+	if (rv == MSR_SCHED_BOTH)
+		msg_conn_sched_proc_msgs(conn);
+	msg_conn_sched_read(conn);
+}
+
+/* collapse this into mgmt_msg_procbufs */
+static void msg_conn_proc_msgs(struct event *thread)
+{
+	struct msg_conn *conn = EVENT_ARG(thread);
+
+	if (mgmt_msg_procbufs(&conn->mstate,
+			      (void (*)(uint8_t, uint8_t *, size_t,
+					void *))conn->handle_msg,
+			      conn, conn->debug))
+		/* there's more, schedule handling more */
+		msg_conn_sched_proc_msgs(conn);
+}
+
+static void msg_conn_sched_read(struct msg_conn *conn)
+{
+	event_add_read(conn->loop, msg_conn_read, conn, conn->fd,
+		       &conn->read_ev);
+}
+
+static void msg_conn_sched_write(struct msg_conn *conn)
+{
+	event_add_write(conn->loop, msg_conn_write, conn, conn->fd,
+			&conn->write_ev);
+}
+
+static void msg_conn_sched_proc_msgs(struct msg_conn *conn)
+{
+	event_add_event(conn->loop, msg_conn_proc_msgs, conn, 0,
+			&conn->proc_msg_ev);
+}
+
+
+void msg_conn_disconnect(struct msg_conn *conn, bool reconnect)
+{
+
+	if (conn->fd != -1) {
+		close(conn->fd);
+		conn->fd = -1;
+
+		/* Notify client through registered callback (if any) */
+		if (conn->notify_disconnect)
+			(void)(*conn->notify_disconnect)(conn);
+	}
+
+	if (reconnect) {
+		assert(conn->is_client);
+		msg_client_sched_connect(
+			container_of(conn, struct msg_client, conn),
+			MSG_CONN_DEFAULT_CONN_RETRY_MSEC);
+	}
+}
+
+int msg_conn_send_msg(struct msg_conn *conn, uint8_t version, void *msg,
+		      size_t mlen, size_t (*packf)(void *, void *))
+{
+	if (conn->fd == -1) {
+		MGMT_MSG_ERR(&conn->mstate,
+			     "can't send message on closed connection");
+		return -1;
+	}
+
+	int rv = mgmt_msg_send_msg(&conn->mstate, version, msg, mlen, packf,
+				   conn->debug);
+
+	msg_conn_sched_write(conn);
+
+	return rv;
+}
+
+void msg_conn_cleanup(struct msg_conn *conn)
+{
+	struct mgmt_msg_state *ms = &conn->mstate;
+
+	if (conn->fd != -1) {
+		close(conn->fd);
+		conn->fd = -1;
+	}
+
+	EVENT_OFF(conn->read_ev);
+	EVENT_OFF(conn->write_ev);
+	EVENT_OFF(conn->proc_msg_ev);
+
+	mgmt_msg_destroy(ms);
+}
+
+/*
+ * Client Connections
+ */
+
+static void msg_client_connect(struct msg_client *conn);
+
+static void msg_client_connect_timer(struct event *thread)
+{
+	msg_client_connect(EVENT_ARG(thread));
+}
+
+static void msg_client_sched_connect(struct msg_client *client,
+				     unsigned long msec)
+{
+	struct msg_conn *conn = &client->conn;
+	const char *dbgtag = conn->debug ? conn->mstate.idtag : NULL;
+
+	MGMT_MSG_DBG(dbgtag, "connection retry in %lu msec", msec);
+	if (msec)
+		event_add_timer_msec(conn->loop, msg_client_connect_timer,
+				     client, msec, &client->conn_retry_tmr);
+	else
+		event_add_event(conn->loop, msg_client_connect_timer, client, 0,
+				&client->conn_retry_tmr);
+}
+
+
+/* Connect and start reading from the socket */
+static void msg_client_connect(struct msg_client *client)
+{
+	struct msg_conn *conn = &client->conn;
+	const char *dbgtag = conn->debug ? conn->mstate.idtag : NULL;
+
+	conn->fd = mgmt_msg_connect(client->sopath, MSG_CONN_SEND_BUF_SIZE,
+				    MSG_CONN_RECV_BUF_SIZE, dbgtag);
+
+	if (conn->fd == -1)
+		/* retry the connection */
+		msg_client_sched_connect(client,
+					 MSG_CONN_DEFAULT_CONN_RETRY_MSEC);
+	else if (client->notify_connect && client->notify_connect(client))
+		/* client connect notify failed */
+		msg_conn_disconnect(conn, true);
+	else
+		/* start reading */
+		msg_conn_sched_read(conn);
+}
+
+void msg_client_init(struct msg_client *client, struct event_loop *tm,
+		     const char *sopath,
+		     int (*notify_connect)(struct msg_client *client),
+		     int (*notify_disconnect)(struct msg_conn *client),
+		     void (*handle_msg)(uint8_t version, uint8_t *data,
+					size_t len, struct msg_conn *client),
+		     size_t max_read_buf, size_t max_write_buf,
+		     size_t max_msg_sz, const char *idtag, bool debug)
+{
+	struct msg_conn *conn = &client->conn;
+	memset(client, 0, sizeof(*client));
+
+	conn->loop = tm;
+	conn->fd = -1;
+	conn->handle_msg = handle_msg;
+	conn->notify_disconnect = notify_disconnect;
+	conn->is_client = true;
+	conn->debug = debug;
+	client->sopath = strdup(sopath);
+	client->notify_connect = notify_connect;
+
+	mgmt_msg_init(&conn->mstate, max_read_buf, max_write_buf, max_msg_sz,
+		      idtag);
+
+	/* XXX maybe just have client kick this off */
+	/* Start trying to connect to server */
+	msg_client_sched_connect(client, 0);
+}
+
+void msg_client_cleanup(struct msg_client *client)
+{
+	assert(client->conn.is_client);
+
+	EVENT_OFF(client->conn_retry_tmr);
+	free(client->sopath);
+
+	msg_conn_cleanup(&client->conn);
+}
+
+/*
+ * Initialize and start reading from the accepted socket
+ *
+ *     notify_connect - only called for disconnect i.e., connected == false
+ */
+void mgmt_msg_server_accept_init(
+	struct msg_conn *conn, struct event_loop *tm, int fd,
+	int (*notify_disconnect)(struct msg_conn *conn),
+	void (*handle_msg)(uint8_t version, uint8_t *data, size_t len,
+			   struct msg_conn *conn),
+	size_t max_read, size_t max_write, size_t max_size, const char *idtag)
+{
+	conn->loop = tm;
+	conn->fd = fd;
+	conn->notify_disconnect = notify_disconnect;
+	conn->handle_msg = handle_msg;
+	conn->is_client = false;
+
+	mgmt_msg_init(&conn->mstate, max_read, max_write, max_size, idtag);
+
+	/* start reading */
+	msg_conn_sched_read(conn);
+
+	/* Make socket non-blocking.  */
+	set_nonblocking(conn->fd);
+	setsockopt_so_sendbuf(conn->fd, MSG_CONN_SEND_BUF_SIZE);
+	setsockopt_so_recvbuf(conn->fd, MSG_CONN_RECV_BUF_SIZE);
+}