Create libosmovty as library from OpenBSC VTY functions
diff --git a/src/vty/telnet_interface.c b/src/vty/telnet_interface.c
new file mode 100644
index 0000000..9069096
--- /dev/null
+++ b/src/vty/telnet_interface.c
@@ -0,0 +1,203 @@
+/* minimalistic telnet/network interface it might turn into a wire interface */
+/* (C) 2009 by Holger Hans Peter Freyther <zecke@selfish.org>
+ * All Rights Reserved
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 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 General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ */
+
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+
+#include <osmocore/msgb.h>
+#include <osmocore/talloc.h>
+#include <osmocore/logging.h>
+
+#include <osmocom/vty/telnet_interface.h>
+#include <osmocom/vty/buffer.h>
+
+/* per connection data */
+LLIST_HEAD(active_connections);
+
+static void *tall_telnet_ctx;
+
+/* per network data */
+static int telnet_new_connection(struct bsc_fd *fd, unsigned int what);
+
+static struct bsc_fd server_socket = {
+	.when	    = BSC_FD_READ,
+	.cb	    = telnet_new_connection,
+	.priv_nr    = 0,
+};
+
+int telnet_init(void *tall_ctx, void *priv, int port)
+{
+	struct sockaddr_in sock_addr;
+	int fd, rc, on = 1;
+
+	tall_telnet_ctx = talloc_named_const(tall_ctx, 1,
+					     "telnet_connection");
+
+	fd = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP);
+
+	if (fd < 0) {
+		LOGP(0, LOGL_ERROR, "Telnet interface socket creation failed\n");
+		return fd;
+	}
+
+	setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
+
+	memset(&sock_addr, 0, sizeof(sock_addr));
+	sock_addr.sin_family = AF_INET;
+	sock_addr.sin_port = htons(port);
+	sock_addr.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
+
+	rc = bind(fd, (struct sockaddr*)&sock_addr, sizeof(sock_addr));
+	if (bind < 0) {
+		LOGP(0, LOGL_ERROR, "Telnet interface failed to bind\n");
+		close(fd);
+		return rc;
+	}
+
+	rc = listen(fd, 0);
+	if (rc < 0) {
+		LOGP(0, LOGL_ERROR, "Telnet interface failed to listen\n");
+		close(fd);
+		return rc;
+	}
+
+	server_socket.data = priv;
+	server_socket.fd = fd;
+	bsc_register_fd(&server_socket);
+
+	return 0;
+}
+
+extern const char *openbsc_copyright;
+
+static void print_welcome(int fd)
+{
+	int ret;
+	static char *msg =
+		"Welcome to the OpenBSC Control interface\n";
+
+	ret = write(fd, msg, strlen(msg));
+	ret = write(fd, openbsc_copyright, strlen(openbsc_copyright));
+}
+
+int telnet_close_client(struct bsc_fd *fd)
+{
+	struct telnet_connection *conn = (struct telnet_connection*)fd->data;
+
+	close(fd->fd);
+	bsc_unregister_fd(fd);
+
+	if (conn->dbg) {
+		log_del_target(conn->dbg);
+		talloc_free(conn->dbg);
+	}
+
+	llist_del(&conn->entry);
+	talloc_free(conn);
+	return 0;
+}
+
+static int client_data(struct bsc_fd *fd, unsigned int what)
+{
+	struct telnet_connection *conn = fd->data;
+	int rc = 0;
+
+	if (what & BSC_FD_READ) {
+		conn->fd.when &= ~BSC_FD_READ;
+		rc = vty_read(conn->vty);
+	}
+
+	/* vty might have been closed from vithin vty_read() */
+	if (!conn->vty)
+		return rc;
+
+	if (what & BSC_FD_WRITE) {
+		rc = buffer_flush_all(conn->vty->obuf, fd->fd);
+		if (rc == BUFFER_EMPTY)
+			conn->fd.when &= ~BSC_FD_WRITE;
+	}
+
+	return rc;
+}
+
+static int telnet_new_connection(struct bsc_fd *fd, unsigned int what)
+{
+	struct telnet_connection *connection;
+	struct sockaddr_in sockaddr;
+	socklen_t len = sizeof(sockaddr);
+	int new_connection = accept(fd->fd, (struct sockaddr*)&sockaddr, &len);
+
+	if (new_connection < 0) {
+		LOGP(0, LOGL_ERROR, "telnet accept failed\n");
+		return new_connection;
+	}
+
+	connection = talloc_zero(tall_telnet_ctx, struct telnet_connection);
+	connection->priv = fd->data;
+	connection->fd.data = connection;
+	connection->fd.fd = new_connection;
+	connection->fd.when = BSC_FD_READ;
+	connection->fd.cb = client_data;
+	bsc_register_fd(&connection->fd);
+	llist_add_tail(&connection->entry, &active_connections);
+
+	print_welcome(new_connection);
+
+	connection->vty = vty_create(new_connection, connection);
+	if (!connection->vty) {
+		LOGP(0, LOGL_ERROR, "couldn't create VTY\n");
+		close(new_connection);
+		talloc_free(connection);
+		return -1;
+	}
+
+	return 0;
+}
+
+/* callback from VTY code */
+void vty_event(enum event event, int sock, struct vty *vty)
+{
+	struct telnet_connection *connection = vty->priv;
+	struct bsc_fd *bfd = &connection->fd;
+
+	if (vty->type != VTY_TERM)
+		return;
+
+	switch (event) {
+	case VTY_READ:
+		bfd->when |= BSC_FD_READ;
+		break;
+	case VTY_WRITE:
+		bfd->when |= BSC_FD_WRITE;
+		break;
+	case VTY_CLOSED:
+		/* vty layer is about to free() vty */
+		connection->vty = NULL;
+		telnet_close_client(bfd);
+		break;
+	default:
+		break;
+	}
+}
+