1 files changed, 310 insertions, 0 deletions
diff --git a/src/osmobts_sock.cpp b/src/osmobts_sock.cpp
new file mode 100644
index 00000000..52c13c42
--- /dev/null
+++ b/src/osmobts_sock.cpp
@@ -0,0 +1,310 @@
+/* osmobts_sock.cpp
+ *
+ * Copyright (C) 2012 Andreas Eversberg <jolly@eversberg.eu>
+ *
+ * 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., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+ */
+
+#include <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <assert.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+extern "C" {
+#include <osmocom/core/talloc.h>
+#include <osmocom/core/select.h>
+#include <osmocom/core/msgb.h>
+}
+
+#include <gprs_rlcmac.h>
+#include <pcu_l1_if.h>
+#include <gprs_debug.h>
+#include <gprs_bssgp_pcu.h>
+#include <pcuif_proto.h>
+#include <bts.h>
+#include <tbf.h>
+
+extern void *tall_pcu_ctx;
+
+extern "C" {
+int l1if_close_pdch(void *obj);
+}
+
+/*
+ * osmo-bts PCU socket functions
+ */
+
+struct pcu_sock_state {
+	struct osmo_fd conn_bfd;	/* fd for connection to lcr */
+	struct osmo_timer_list timer;	/* socket connect retry timer */
+	struct llist_head upqueue;	/* queue for sending messages */
+} *pcu_sock_state = NULL;
+
+static void pcu_sock_timeout(void *_priv);
+
+int pcu_sock_send(struct msgb *msg)
+{
+	struct pcu_sock_state *state = pcu_sock_state;
+	struct osmo_fd *conn_bfd;
+
+	if (!state) {
+		LOGP(DL1IF, LOGL_NOTICE, "PCU socket not created, dropping "
+			"message\n");
+		return -EINVAL;
+	}
+	conn_bfd = &state->conn_bfd;
+	if (conn_bfd->fd <= 0) {
+		LOGP(DL1IF, LOGL_NOTICE, "PCU socket not connected, dropping "
+			"message\n");
+		return -EIO;
+	}
+	msgb_enqueue(&state->upqueue, msg);
+	conn_bfd->when |= BSC_FD_WRITE;
+
+	return 0;
+}
+
+static void pcu_sock_close(struct pcu_sock_state *state, int lost)
+{
+	struct osmo_fd *bfd = &state->conn_bfd;
+	struct gprs_rlcmac_bts *bts = bts_main_data();
+	uint8_t trx, ts;
+
+	LOGP(DL1IF, LOGL_NOTICE, "PCU socket has %s connection\n",
+		(lost) ? "LOST" : "closed");
+
+	close(bfd->fd);
+	bfd->fd = -1;
+	osmo_fd_unregister(bfd);
+
+	/* flush the queue */
+	while (!llist_empty(&state->upqueue)) {
+		struct msgb *msg = msgb_dequeue(&state->upqueue);
+		msgb_free(msg);
+	}
+
+	/* disable all slots, kick all TBFs */
+	for (trx = 0; trx < 8; trx++) {
+#ifdef ENABLE_SYSMODSP
+		if (bts->trx[trx].fl1h) {
+			l1if_close_pdch(bts->trx[trx].fl1h);
+			bts->trx[trx].fl1h = NULL;
+		}
+#endif
+		for (ts = 0; ts < 8; ts++)
+			bts->trx[trx].pdch[ts].disable();
+#warning "NOT ALL RESOURCES are freed in this case... inconsistent with the other code. Share the code with pcu_l1if.c for the reset."
+		gprs_rlcmac_tbf::free_all(&bts->trx[trx]);
+	}
+
+	gprs_bssgp_destroy();
+	exit(0);
+}
+
+static int pcu_sock_read(struct osmo_fd *bfd)
+{
+	struct pcu_sock_state *state = (struct pcu_sock_state *)bfd->data;
+	struct gsm_pcu_if *pcu_prim;
+	struct msgb *msg;
+	int rc;
+
+	msg = msgb_alloc(sizeof(*pcu_prim), "pcu_sock_rx");
+	if (!msg)
+		return -ENOMEM;
+
+	pcu_prim = (struct gsm_pcu_if *) msg->tail;
+
+	rc = recv(bfd->fd, msg->tail, msgb_tailroom(msg), 0);
+	if (rc == 0)
+		goto close;
+
+	if (rc < 0) {
+		if (errno == EAGAIN)
+			return 0;
+		goto close;
+	}
+
+	rc = pcu_rx(pcu_prim->msg_type, pcu_prim);
+
+	/* as we always synchronously process the message in pcu_rx() and
+	 * its callbacks, we can free the message here. */
+	msgb_free(msg);
+
+	return rc;
+
+close:
+	msgb_free(msg);
+	pcu_sock_close(state, 1);
+	return -1;
+}
+
+static int pcu_sock_write(struct osmo_fd *bfd)
+{
+	struct pcu_sock_state *state = (struct pcu_sock_state *)bfd->data;
+	int rc;
+
+	while (!llist_empty(&state->upqueue)) {
+		struct msgb *msg, *msg2;
+		struct gsm_pcu_if *pcu_prim;
+
+		/* peek at the beginning of the queue */
+		msg = llist_entry(state->upqueue.next, struct msgb, list);
+		pcu_prim = (struct gsm_pcu_if *)msg->data;
+
+		bfd->when &= ~BSC_FD_WRITE;
+
+		/* bug hunter 8-): maybe someone forgot msgb_put(...) ? */
+		if (!msgb_length(msg)) {
+			LOGP(DL1IF, LOGL_ERROR, "message type (%d) with ZERO "
+				"bytes!\n", pcu_prim->msg_type);
+			goto dontsend;
+		}
+
+		/* try to send it over the socket */
+		rc = write(bfd->fd, msgb_data(msg), msgb_length(msg));
+		if (rc == 0)
+			goto close;
+		if (rc < 0) {
+			if (errno == EAGAIN) {
+				bfd->when |= BSC_FD_WRITE;
+				break;
+			}
+			goto close;
+		}
+
+dontsend:
+		/* _after_ we send it, we can deueue */
+		msg2 = msgb_dequeue(&state->upqueue);
+		assert(msg == msg2);
+		msgb_free(msg);
+	}
+	return 0;
+
+close:
+	pcu_sock_close(state, 1);
+
+	return -1;
+}
+
+static int pcu_sock_cb(struct osmo_fd *bfd, unsigned int flags)
+{
+	int rc = 0;
+
+	if (flags & BSC_FD_READ)
+		rc = pcu_sock_read(bfd);
+	if (rc < 0)
+		return rc;
+
+	if (flags & BSC_FD_WRITE)
+		rc = pcu_sock_write(bfd);
+
+	return rc;
+}
+
+int pcu_l1if_open(void)
+{
+	struct pcu_sock_state *state;
+	struct osmo_fd *bfd;
+	struct sockaddr_un local;
+	unsigned int namelen;
+	int rc;
+
+	state = pcu_sock_state;
+	if (!state) {
+		state = talloc_zero(tall_pcu_ctx, struct pcu_sock_state);
+		if (!state)
+			return -ENOMEM;
+		INIT_LLIST_HEAD(&state->upqueue);
+	}
+
+	bfd = &state->conn_bfd;
+
+	bfd->fd = socket(AF_UNIX, SOCK_SEQPACKET, 0);
+	if (bfd->fd < 0) {
+		LOGP(DL1IF, LOGL_ERROR, "Failed to create PCU socket.\n");
+		talloc_free(state);
+		return -1;
+	}
+
+	local.sun_family = AF_UNIX;
+	strncpy(local.sun_path, "/tmp/pcu_bts", sizeof(local.sun_path));
+	local.sun_path[sizeof(local.sun_path) - 1] = '\0';
+
+	/* we use the same magic that X11 uses in Xtranssock.c for
+	 * calculating the proper length of the sockaddr */
+#if defined(BSD44SOCKETS) || defined(__UNIXWARE__)
+	local.sun_len = strlen(local.sun_path);
+#endif
+#if defined(BSD44SOCKETS) || defined(SUN_LEN)
+	namelen = SUN_LEN(&local);
+#else
+	namelen = strlen(local.sun_path) +
+		  offsetof(struct sockaddr_un, sun_path);
+#endif
+	rc = connect(bfd->fd, (struct sockaddr *) &local, namelen);
+	if (rc != 0) {
+		LOGP(DL1IF, LOGL_ERROR, "Failed to connect to the osmo-bts"
+			"PCU socket, delaying... '%s'\n", local.sun_path);
+		pcu_sock_state = state;
+		close(bfd->fd);
+		bfd->fd = -1;
+		state->timer.cb = pcu_sock_timeout;
+		osmo_timer_schedule(&state->timer, 5, 0);
+		return 0;
+	}
+
+	bfd->when = BSC_FD_READ;
+	bfd->cb = pcu_sock_cb;
+	bfd->data = state;
+
+	rc = osmo_fd_register(bfd);
+	if (rc < 0) {
+		LOGP(DL1IF, LOGL_ERROR, "Could not register PCU fd: %d\n", rc);
+		close(bfd->fd);
+		talloc_free(state);
+		return rc;
+	}
+
+	LOGP(DL1IF, LOGL_NOTICE, "osmo-bts PCU socket has been connected\n");
+
+	pcu_sock_state = state;
+
+	return 0;
+}
+
+void pcu_l1if_close(void)
+{
+	struct pcu_sock_state *state = pcu_sock_state;
+	struct osmo_fd *bfd;
+
+	if (!state)
+		return;
+
+	osmo_timer_del(&state->timer);
+
+	bfd = &state->conn_bfd;
+	if (bfd->fd > 0)
+		pcu_sock_close(state, 0);
+	talloc_free(state);
+	pcu_sock_state = NULL;
+}
+
+static void pcu_sock_timeout(void *_priv)
+{
+	pcu_l1if_open();
+}