dissolve libbsc: move all to src/osmo-bsc, link .o files

Move all of libbsc/ into osmo-bsc/, and separate/move some implementations to
allow linking from utils/* and ipaccess/* without pulling in unccessary
dependencies.

Some utilities use gsm_network and gsm_bts structs, which already include data
structures for fairly advanced uses. Move initialization that only osmo-bsc
needs into new bsc_network_init() and bsc_bts_alloc_register() functions, so
that the leaner tools can use the old gsm_* versions without the need to link
everything (e.g. handover and lchan alloc code).

In some instances, there need to be stubs if to cut off linking "just before
the RSL level" and prevent dependencies from creeping in.
- abis_rsl_rcvmsg(): the only program currently interpreting RSL messages is
  osmo-bsc, the utils are merely concerned with OML, if at all.
- paging_flush_bts(): ip.access nanobts models call this when the RSL link is
  dropped. Only osmo-bsc actually needs to do anything there.
- on_gsm_ts_init(): the mechanism to trigger timeslot initialization is related
  to OML, while this action to take on init would pull in RSL dependencies.
utils/ and ipaccess/ each have a stubs.c file to implement these stubs. Tests
implement stubs inline where required.

From src/utils/, src/ipaccess/ and tests/*/, link in .o files from osmo-bsc/.
In order for this to work, the osmo-bsc subdir must be built before the other
source trees. (An alternative would be to include the .c files as sources, but
that would re-compile them in every source tree. Not a large burden really, but
unless linking .o files gives problems, let's have the quicker build.)

Minor obvious cleanups creep in with this patch, I will not bother to name them
individually now unless code review asks me to.

Rationale:

1) libbsc has been separate to use it for osmo-nitb and osmo-bsc in the old
openbsc.git. This is no longer required, and spreading over libbsc and osmo-bsc
is distracting.

2) Recently, ridiculous linking requirements have made adding new functions
cumbersome, because libbsc has started depending on osmo-bsc/*.c
implementations: on gscon FSM and bssap functions. For example, neither
bs11_config nor ipaccess-config nor bts_test need handover_cfg or BSSMAP
message composition. It makes no sense to link the entire osmo-bsc to it, nor
do we want to keep adding stubs to each linking realm.

Change-Id: I36a586726f5818121abe54d25654819fc451d3bf

1 files changed, 299 insertions, 0 deletions

diff --git a/src/osmo-bsc/e1_config.c b/src/osmo-bsc/e1_config.c
new file mode 100644
index 000000000..e7398ed9c
--- /dev/null
+++ b/src/osmo-bsc/e1_config.c
@@ -0,0 +1,299 @@
+/* OpenBSC E1 Input code */
+
+/* (C) 2008-2010 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 <string.h>
+#include <errno.h>
+#include <time.h>
+#include <netinet/in.h>
+
+#include <osmocom/bsc/gsm_data.h>
+#include <osmocom/abis/e1_input.h>
+#include <osmocom/bsc/misdn.h>
+#include <osmocom/abis/ipaccess.h>
+#include <osmocom/core/talloc.h>
+#include <osmocom/bsc/debug.h>
+#include <osmocom/bsc/abis_rsl.h>
+
+#define SAPI_L2ML	0
+#define SAPI_OML	62
+#define SAPI_RSL	0	/* 63 ? */
+
+/* The e1_reconfig_*() functions below take the configuration present in the
+ * bts/trx/ts data structures and ensure the E1 configuration reflects the
+ * timeslot/subslot/TEI configuration */
+
+int e1_reconfig_ts(struct gsm_bts_trx_ts *ts)
+{
+	struct gsm_e1_subslot *e1_link = &ts->e1_link;
+	struct e1inp_line *line;
+
+	DEBUGP(DLMI, "e1_reconfig_ts(%u,%u,%u)\n", ts->trx->bts->nr, ts->trx->nr, ts->nr);
+
+	if (!e1_link->e1_ts) {
+		LOGP(DLINP, LOGL_ERROR, "TS (%u/%u/%u) without E1 timeslot?\n",
+		     ts->nr, ts->trx->nr, ts->trx->bts->nr);
+		return 0;
+	}
+
+	line = e1inp_line_find(e1_link->e1_nr);
+	if (!line) {
+		LOGP(DLINP, LOGL_ERROR, "TS (%u/%u/%u) referring to "
+		     "non-existing E1 line %u\n", ts->nr, ts->trx->nr,
+		     ts->trx->bts->nr, e1_link->e1_nr);
+		return -ENOMEM;
+	}
+
+	return 0;
+}
+
+int e1_reconfig_trx(struct gsm_bts_trx *trx)
+{
+	struct gsm_e1_subslot *e1_link = &trx->rsl_e1_link;
+	struct e1inp_ts *sign_ts;
+	struct e1inp_line *line;
+	struct e1inp_sign_link *rsl_link;
+	int i;
+
+	if (!e1_link->e1_ts) {
+		LOGP(DLINP, LOGL_ERROR, "TRX (%u/%u) RSL link without "
+		     "timeslot?\n", trx->bts->nr, trx->nr);
+		return -EINVAL;
+	}
+
+	/* RSL Link */
+	line = e1inp_line_find(e1_link->e1_nr);
+	if (!line) {
+		LOGP(DLINP, LOGL_ERROR, "TRX (%u/%u) RSL link referring "
+		     "to non-existing E1 line %u\n", trx->bts->nr,
+		     trx->nr, e1_link->e1_nr);
+		return -ENOMEM;
+	}
+	sign_ts = &line->ts[e1_link->e1_ts-1];
+	e1inp_ts_config_sign(sign_ts, line);
+	/* Ericsson RBS have a per-TRX OML link in parallel to RSL */
+	if (trx->bts->type == GSM_BTS_TYPE_RBS2000) {
+		struct e1inp_sign_link *oml_link;
+		oml_link = e1inp_sign_link_create(sign_ts, E1INP_SIGN_OML, trx,
+						  trx->rsl_tei, SAPI_OML);
+		if (!oml_link) {
+			LOGP(DLINP, LOGL_ERROR, "TRX (%u/%u) OML link creation "
+				"failed\n", trx->bts->nr, trx->nr);
+			return -ENOMEM;
+		}
+		if (trx->oml_link)
+			e1inp_sign_link_destroy(trx->oml_link);
+		trx->oml_link = oml_link;
+	}
+	rsl_link = e1inp_sign_link_create(sign_ts, E1INP_SIGN_RSL,
+					  trx, trx->rsl_tei, SAPI_RSL);
+	if (!rsl_link) {
+		LOGP(DLINP, LOGL_ERROR, "TRX (%u/%u) RSL link creation "
+		     "failed\n", trx->bts->nr, trx->nr);
+		return -ENOMEM;
+	}
+	if (trx->rsl_link)
+		e1inp_sign_link_destroy(trx->rsl_link);
+	trx->rsl_link = rsl_link;
+
+	for (i = 0; i < TRX_NR_TS; i++)
+		e1_reconfig_ts(&trx->ts[i]);
+
+	return 0;
+}
+
+/* this is the generic callback for all ISDN-based BTS. */
+static int bts_isdn_sign_link(struct msgb *msg)
+{
+	int ret = -EINVAL;
+	struct e1inp_sign_link *link = msg->dst;
+	struct gsm_bts *bts;
+
+	switch (link->type) {
+	case E1INP_SIGN_OML:
+		bts = link->trx->bts;
+		ret = bts->model->oml_rcvmsg(msg);
+		break;
+	case E1INP_SIGN_RSL:
+		if (link->trx->mo.nm_state.administrative == NM_STATE_LOCKED) {
+			LOGP(DLMI, LOGL_ERROR, "(bts=%d/trx=%d) discarding RSL message received "
+			     "in locked administrative state\n", link->trx->bts->nr, link->trx->nr);
+			msgb_free(msg);
+			break;
+		}
+		ret = abis_rsl_rcvmsg(msg);
+		break;
+	default:
+		LOGP(DLMI, LOGL_ERROR, "unknown link type %u\n", link->type);
+		msgb_free(msg);
+		break;
+	}
+	return ret;
+}
+
+struct e1inp_line_ops bts_isdn_e1inp_line_ops = {
+	.sign_link	= bts_isdn_sign_link,
+};
+
+int e1_reconfig_bts(struct gsm_bts *bts)
+{
+	struct gsm_e1_subslot *e1_link = &bts->oml_e1_link;
+	struct e1inp_ts *sign_ts;
+	struct e1inp_line *line;
+	struct e1inp_sign_link *oml_link;
+	struct gsm_bts_trx *trx;
+	struct timespec tp;
+	int rc;
+
+	DEBUGP(DLMI, "e1_reconfig_bts(%u)\n", bts->nr);
+
+	line = e1inp_line_find(e1_link->e1_nr);
+	if (!line) {
+		LOGP(DLINP, LOGL_ERROR, "BTS %u OML link referring to "
+		     "non-existing E1 line %u\n", bts->nr, e1_link->e1_nr);
+		return -ENOMEM;
+	}
+
+	if (!bts->model->e1line_bind_ops) {
+		LOGP(DLINP, LOGL_ERROR, "no callback to bind E1 line operations\n");
+		return -EINVAL;
+	}
+	if (!line->ops)
+		bts->model->e1line_bind_ops(line);
+
+	/* skip signal link initialization, this is done later for these BTS. */
+	if (bts->type == GSM_BTS_TYPE_NANOBTS ||
+	    bts->type == GSM_BTS_TYPE_OSMOBTS)
+		return e1inp_line_update(line);
+
+	/* OML link */
+	if (!e1_link->e1_ts) {
+		LOGP(DLINP, LOGL_ERROR, "BTS %u OML link without timeslot?\n",
+		     bts->nr);
+		return -EINVAL;
+	}
+
+	sign_ts = &line->ts[e1_link->e1_ts-1];
+	e1inp_ts_config_sign(sign_ts, line);
+	oml_link = e1inp_sign_link_create(sign_ts, E1INP_SIGN_OML,
+					  bts->c0, bts->oml_tei, SAPI_OML);
+	if (!oml_link) {
+		LOGP(DLINP, LOGL_ERROR, "BTS %u OML link creation failed\n",
+		     bts->nr);
+		return -ENOMEM;
+	}
+	if (bts->oml_link)
+		e1inp_sign_link_destroy(bts->oml_link);
+	bts->oml_link = oml_link;
+	rc = clock_gettime(CLOCK_MONOTONIC, &tp);
+	bts->uptime = (rc < 0) ? 0 : tp.tv_sec; /* we don't need sub-second precision for uptime */
+
+	llist_for_each_entry(trx, &bts->trx_list, list)
+		e1_reconfig_trx(trx);
+
+	/* notify E1 input something has changed */
+	return e1inp_line_update(line);
+}
+
+#if 0
+/* do some compiled-in configuration for our BTS/E1 setup */
+int e1_config(struct gsm_bts *bts, int cardnr, int release_l2)
+{
+	struct e1inp_line *line;
+	struct e1inp_ts *sign_ts;
+	struct e1inp_sign_link *oml_link, *rsl_link;
+	struct gsm_bts_trx *trx = bts->c0;
+	int base_ts;
+
+	switch (bts->nr) {
+	case 0:
+		/* First BTS uses E1 TS 01,02,03,04,05 */
+		base_ts = HARDCODED_BTS0_TS - 1;
+		break;
+	case 1:
+		/* Second BTS uses E1 TS 06,07,08,09,10 */
+		base_ts = HARDCODED_BTS1_TS - 1;
+		break;
+	case 2:
+		/* Third BTS uses E1 TS 11,12,13,14,15 */
+		base_ts = HARDCODED_BTS2_TS - 1;
+	default:
+		return -EINVAL;
+	}
+
+	line = talloc_zero(tall_bsc_ctx, struct e1inp_line);
+	if (!line)
+		return -ENOMEM;
+
+	/* create E1 timeslots for signalling and TRAU frames */
+	e1inp_ts_config(&line->ts[base_ts+1-1], line, E1INP_TS_TYPE_SIGN);
+	e1inp_ts_config(&line->ts[base_ts+2-1], line, E1INP_TS_TYPE_TRAU);
+	e1inp_ts_config(&line->ts[base_ts+3-1], line, E1INP_TS_TYPE_TRAU);
+
+	/* create signalling links for TS1 */
+	sign_ts = &line->ts[base_ts+1-1];
+	oml_link = e1inp_sign_link_create(sign_ts, E1INP_SIGN_OML,
+					  trx, TEI_OML, SAPI_OML);
+	rsl_link = e1inp_sign_link_create(sign_ts, E1INP_SIGN_RSL,
+					  trx, TEI_RSL, SAPI_RSL);
+
+	/* create back-links from bts/trx */
+	bts->oml_link = oml_link;
+	trx->rsl_link = rsl_link;
+
+	/* enable subchannel demuxer on TS2 */
+	subch_demux_activate(&line->ts[base_ts+2-1].trau.demux, 1);
+	subch_demux_activate(&line->ts[base_ts+2-1].trau.demux, 2);
+	subch_demux_activate(&line->ts[base_ts+2-1].trau.demux, 3);
+
+	/* enable subchannel demuxer on TS3 */
+	subch_demux_activate(&line->ts[base_ts+3-1].trau.demux, 0);
+	subch_demux_activate(&line->ts[base_ts+3-1].trau.demux, 1);
+	subch_demux_activate(&line->ts[base_ts+3-1].trau.demux, 2);
+	subch_demux_activate(&line->ts[base_ts+3-1].trau.demux, 3);
+
+	trx = gsm_bts_trx_num(bts, 1);
+	if (trx) {
+		/* create E1 timeslots for TRAU frames of TRX1 */
+		e1inp_ts_config(&line->ts[base_ts+4-1], line, E1INP_TS_TYPE_TRAU);
+		e1inp_ts_config(&line->ts[base_ts+5-1], line, E1INP_TS_TYPE_TRAU);
+
+		/* create RSL signalling link for TRX1 */
+		sign_ts = &line->ts[base_ts+1-1];
+		rsl_link = e1inp_sign_link_create(sign_ts, E1INP_SIGN_RSL,
+					  trx, TEI_RSL+1, SAPI_RSL);
+		/* create back-links from trx */
+		trx->rsl_link = rsl_link;
+
+		/* enable subchannel demuxer on TS2 */
+		subch_demux_activate(&line->ts[base_ts+4-1].trau.demux, 0);
+		subch_demux_activate(&line->ts[base_ts+4-1].trau.demux, 1);
+		subch_demux_activate(&line->ts[base_ts+4-1].trau.demux, 2);
+		subch_demux_activate(&line->ts[base_ts+4-1].trau.demux, 3);
+
+		/* enable subchannel demuxer on TS3 */
+		subch_demux_activate(&line->ts[base_ts+5-1].trau.demux, 0);
+		subch_demux_activate(&line->ts[base_ts+5-1].trau.demux, 1);
+		subch_demux_activate(&line->ts[base_ts+5-1].trau.demux, 2);
+		subch_demux_activate(&line->ts[base_ts+5-1].trau.demux, 3);
+	}
+
+	return mi_setup(cardnr, line, release_l2);
+}
+#endif