mncc: Add code to manage the mncc connection for CC

Connect, re-connect and read messages from the MNCC socket. Dispatch
the event in case the system got disconnected.

Move the app definition to app.h and use it everywhere. Begin with a
new call for mncc.

src/Makefile.am

@@ -2,7 +2,11 @@ bin_PROGRAMS = osmo-sip-connector
 
 AM_CFLAGS=-Wall $(LIBOSMOCORE_CFLAGS) $(LIBOSMOVTY_CFLAGS) $(SOFIASIP_CFLAGS)
 
+noinst_HEADERS = \
+	evpoll.h vty.h mncc_protocol.h app.h mncc.h
+
 osmo_sip_connector_SOURCES = \
+		mncc.c \
 		evpoll.c \
 		vty.c \
 		main.c

src/app.h

@@ -0,0 +1,22 @@
+#pragma once
+
+#include "mncc.h"
+
+struct app_config {
+	struct {
+		const char *local_addr;
+		int local_port;
+
+		const char *remote_addr;
+		int remote_port;
+	} sip;
+
+	struct {
+		const char *path;
+		struct mncc_connection conn;
+	} mncc;
+
+	//int use_imsi_as_id;
+};
+
+extern struct app_config g_app;

src/main.c

@@ -23,6 +23,8 @@
 #include "evpoll.h"
 #include "vty.h"
 #include "logging.h"
+#include "mncc.h"
+#include "app.h"
 
 #include <osmocom/core/application.h>
 #include <osmocom/core/utils.h>
@@ -139,7 +141,8 @@ int main(int argc, char **argv)
 	if (rc < 0)
 		exit(1);
 
-
+	mncc_connection_init(&g_app.mncc.conn, &g_app);
+	mncc_connection_start(&g_app.mncc.conn);
 
 	/* marry sofia-sip to glib and glib to libosmocore */
 	loop = g_main_loop_new(NULL, FALSE);

src/mncc.c

@@ -0,0 +1,84 @@
+/*
+ * (C) 2016 by Holger Hans Peter Freyther
+ *
+ * All Rights Reserved
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include "mncc.h"
+#include "app.h"
+#include "logging.h"
+
+#include <osmocom/core/socket.h>
+
+#include <sys/socket.h>
+#include <sys/un.h>
+
+#include <errno.h>
+#include <unistd.h>
+
+static void mncc_reconnect(void *data)
+{
+	int rc;
+	struct mncc_connection *conn = data;
+
+	rc = osmo_sock_unix_init_ofd(&conn->fd, SOCK_SEQPACKET, 0,
+					conn->app->mncc.path, OSMO_SOCK_F_CONNECT);
+	if (rc < 0) {
+		LOGP(DMNCC, LOGL_ERROR, "Failed to connect(%s). Retrying\n",
+			conn->app->mncc.path);
+		osmo_timer_schedule(&conn->reconnect, 5, 0);
+		return;
+	}
+
+	LOGP(DMNCC, LOGL_NOTICE, "Reconnected to %s\n", conn->app->mncc.path);
+}
+
+static int mncc_data(struct osmo_fd *fd, unsigned int what)
+{
+	char buf[4096];
+	int rc;
+	struct mncc_connection *conn = fd->data;
+
+	rc = read(fd->fd, buf, sizeof(buf));
+	if (rc <= 0) {
+		LOGP(DMNCC, LOGL_ERROR, "Failed to read %d/%s. Re-connecting.\n",
+			rc, strerror(errno));
+		osmo_fd_unregister(fd);
+		close(fd->fd);
+		osmo_timer_schedule(&conn->reconnect, 5, 0);
+		if (conn->on_disconnect)
+			conn->on_disconnect(conn);
+		return 0;
+	}
+
+	return 0;
+}
+
+void mncc_connection_init(struct mncc_connection *conn, struct app_config *cfg)
+{
+	conn->reconnect.cb = mncc_reconnect;
+	conn->reconnect.data = conn;
+	conn->fd.cb = mncc_data;
+	conn->fd.data = conn;
+	conn->app = cfg;
+}
+
+void mncc_connection_start(struct mncc_connection *conn)
+{
+	LOGP(DMNCC, LOGL_NOTICE, "Scheduling MNCC connect\n");
+	osmo_timer_schedule(&conn->reconnect, 0, 0);
+}

src/mncc.h

@@ -0,0 +1,20 @@
+#pragma once
+
+#include <osmocom/core/select.h>
+#include <osmocom/core/timer.h>
+
+struct app_config;
+
+struct mncc_connection {
+	struct app_config *app;
+	struct osmo_fd fd;
+
+	struct osmo_timer_list reconnect;
+
+
+	/* callback for application logic */
+	void (*on_disconnect)(struct mncc_connection *);
+};
+
+void mncc_connection_init(struct mncc_connection *conn, struct app_config *cfg);
+void mncc_connection_start(struct mncc_connection *conn);

src/vty.c

@@ -19,6 +19,7 @@
  */
 
 #include "vty.h"
+#include "app.h"
 
 #include <talloc.h>
 

src/vty.h

@@ -9,20 +9,4 @@ enum {
 	APP_NODE,
 };
 
-struct app_config {
-	struct {
-		const char *local_addr;
-		int local_port;
-
-		const char *remote_addr;
-		int remote_port;
-	} sip;
-
-	struct {
-		const char *path;
-	} mncc;
-
-	//int use_imsi_as_id;
-};
-
 void mncc_sip_vty_init();