re-structure the OpenBSC directory layout

The new structure divides the code into a number of libraries
for the BSC core functionality, MSC core functionality, Abis transport,
TRAU and other bits.

This doesn't introduce any functional code change but simply moves
around files and alters Makefile.am accordingly.

Next step would be to disentangle a lot of the inter-library
dependencies and make the individual bits of code more independent.

1 files changed, 248 insertions, 0 deletions

diff --git a/openbsc/src/utils/rs232.c b/openbsc/src/utils/rs232.c
new file mode 100644
index 000000000..75505710f
--- /dev/null
+++ b/openbsc/src/utils/rs232.c
@@ -0,0 +1,248 @@
+/* OpenBSC BS-11 T-Link interface using POSIX serial port */
+
+/* (C) 2008-2009 by Harald Welte <laforge@gnumonks.org>
+ *
+ * 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 Affero 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 <unistd.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <errno.h>
+#include <string.h>
+#include <termios.h>
+#include <fcntl.h>
+
+#include <osmocore/select.h>
+#include <osmocore/msgb.h>
+#include <openbsc/debug.h>
+#include <openbsc/gsm_data.h>
+#include <openbsc/rs232.h>
+
+/* adaption layer from GSM 08.59 + 12.21 to RS232 */
+
+struct serial_handle {
+	struct bsc_fd fd;
+	struct llist_head tx_queue;
+
+	struct msgb *rx_msg;
+	unsigned int rxmsg_bytes_missing;
+
+	unsigned int delay_ms;
+	struct gsm_bts *bts;
+};
+
+/* FIXME: this needs to go */
+static struct serial_handle _ser_handle, *ser_handle = &_ser_handle;
+
+#define LAPD_HDR_LEN	10
+
+static int handle_ser_write(struct bsc_fd *bfd);
+
+/* callback from abis_nm */
+int _abis_nm_sendmsg(struct msgb *msg, int to_trx_oml)
+{
+	struct serial_handle *sh = ser_handle;
+	u_int8_t *lapd;
+	unsigned int len;
+
+	msg->l2h = msg->data;
+
+	/* prepend LAPD header */
+	lapd = msgb_push(msg, LAPD_HDR_LEN);
+
+	len = msg->len - 2;
+
+	lapd[0] = (len >> 8) & 0xff;
+	lapd[1] = len & 0xff; /* length of bytes startign at lapd[2] */
+	lapd[2] = 0x00;
+	lapd[3] = 0x07;
+	lapd[4] = 0x01;
+	lapd[5] = 0x3e;
+	lapd[6] = 0x00;
+	lapd[7] = 0x00;
+	lapd[8] = msg->len - 10; /* length of bytes starting at lapd[10] */
+	lapd[9] = lapd[8] ^ 0x38;
+
+	msgb_enqueue(&sh->tx_queue, msg);
+	sh->fd.when |= BSC_FD_WRITE;
+
+	/* we try to immediately send */
+	handle_ser_write(&sh->fd);
+
+	return 0;
+}
+
+/* select.c callback in case we can write to the RS232 */
+static int handle_ser_write(struct bsc_fd *bfd)
+{
+	struct serial_handle *sh = bfd->data;
+	struct msgb *msg;
+	int written;
+
+	msg = msgb_dequeue(&sh->tx_queue);
+	if (!msg) {
+		bfd->when &= ~BSC_FD_WRITE;
+		return 0;
+	}
+
+	DEBUGP(DMI, "RS232 TX: %s\n", hexdump(msg->data, msg->len));
+
+	/* send over serial line */
+	written = write(bfd->fd, msg->data, msg->len);
+	if (written < msg->len) {
+		perror("short write:");
+		msgb_free(msg);
+		return -1;
+	}
+
+	msgb_free(msg);
+	usleep(sh->delay_ms*1000);
+
+	return 0;
+}
+
+#define SERIAL_ALLOC_SIZE	300
+
+/* select.c callback in case we can read from the RS232 */
+static int handle_ser_read(struct bsc_fd *bfd)
+{
+	struct serial_handle *sh = bfd->data;
+	struct msgb *msg;
+	int rc = 0;
+
+	if (!sh->rx_msg) {
+		sh->rx_msg = msgb_alloc(SERIAL_ALLOC_SIZE, "RS232 Rx");
+		sh->rx_msg->l2h = NULL;
+		sh->rx_msg->trx = sh->bts->c0;
+	}
+	msg = sh->rx_msg;
+
+	/* first read two byes to obtain length */
+	if (msg->len < 2) {
+		rc = read(sh->fd.fd, msg->tail, 2 - msg->len);
+		if (rc < 0) {
+			perror("ERROR reading from serial port");
+			msgb_free(msg);
+			return rc;
+		}
+		msgb_put(msg, rc);
+
+		if (msg->len >= 2) {
+			/* parse LAPD payload length */
+			if (msg->data[0] != 0)
+				fprintf(stderr, "Suspicious header byte 0: 0x%02x\n",
+					msg->data[0]);
+
+			sh->rxmsg_bytes_missing = msg->data[0] << 8;
+			sh->rxmsg_bytes_missing += msg->data[1];
+
+			if (sh->rxmsg_bytes_missing < LAPD_HDR_LEN -2)
+				fprintf(stderr, "Invalid length in hdr: %u\n",
+					sh->rxmsg_bytes_missing);
+		}
+	} else {
+		/* try to read as many of the missing bytes as are available */
+		rc = read(sh->fd.fd, msg->tail, sh->rxmsg_bytes_missing);
+		if (rc < 0) {
+			perror("ERROR reading from serial port");
+			msgb_free(msg);
+			return rc;
+		}
+		msgb_put(msg, rc);
+		sh->rxmsg_bytes_missing -= rc;
+
+		if (sh->rxmsg_bytes_missing == 0) {
+			/* we have one complete message now */
+			sh->rx_msg = NULL;
+
+			if (msg->len > LAPD_HDR_LEN)
+				msg->l2h = msg->data + LAPD_HDR_LEN;
+
+			DEBUGP(DMI, "RS232 RX: %s\n", hexdump(msg->data, msg->len));
+			rc = handle_serial_msg(msg);
+		}
+	}
+
+	return rc;
+}
+
+/* select.c callback */
+static int serial_fd_cb(struct bsc_fd *bfd, unsigned int what)
+{
+	int rc = 0;
+
+	if (what & BSC_FD_READ)
+		rc = handle_ser_read(bfd);
+
+	if (rc < 0)
+		return rc;
+
+	if (what & BSC_FD_WRITE)
+		rc = handle_ser_write(bfd);
+
+	return rc;
+}
+
+int rs232_setup(const char *serial_port, unsigned int delay_ms,
+		struct gsm_bts *bts)
+{
+	int rc, serial_fd;
+	struct termios tio;
+
+	serial_fd = open(serial_port, O_RDWR);
+	if (serial_fd < 0) {
+		perror("cannot open serial port:");
+		return serial_fd;
+	}
+
+	/* set baudrate */
+	rc = tcgetattr(serial_fd, &tio);
+	if (rc < 0) {
+		perror("tcgetattr()");
+		return rc;
+	}
+	cfsetispeed(&tio, B19200);
+	cfsetospeed(&tio, B19200);
+	tio.c_cflag |=  (CREAD | CLOCAL | CS8);
+	tio.c_cflag &= ~(PARENB | CSTOPB | CSIZE | CRTSCTS);
+	tio.c_lflag &= ~(ICANON | ECHO | ECHOE | ISIG);
+	tio.c_iflag |=  (INPCK | ISTRIP);
+	tio.c_iflag &= ~(ISTRIP | IXON | IXOFF | IGNBRK | INLCR | ICRNL | IGNCR);
+	tio.c_oflag &= ~(OPOST);
+	rc = tcsetattr(serial_fd, TCSADRAIN, &tio);
+	if (rc < 0) {
+		perror("tcsetattr()");
+		return rc;
+	}
+
+	INIT_LLIST_HEAD(&ser_handle->tx_queue);
+	ser_handle->fd.fd = serial_fd;
+	ser_handle->fd.when = BSC_FD_READ;
+	ser_handle->fd.cb = serial_fd_cb;
+	ser_handle->fd.data = ser_handle;
+	ser_handle->delay_ms = delay_ms;
+	ser_handle->bts = bts;
+	rc = bsc_register_fd(&ser_handle->fd);
+	if (rc < 0) {
+		fprintf(stderr, "could not register FD: %s\n",
+			strerror(rc));
+		return rc;
+	}
+
+	return 0;
+}