diff options
author | Neels Hofmeyr <nhofmeyr@sysmocom.de> | 2017-05-08 15:12:20 +0200 |
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committer | Neels Hofmeyr <neels@hofmeyr.de> | 2017-08-08 19:17:53 +0200 |
commit | e2f24d53e4f80b34ec6d656d93127cb598229a96 (patch) | |
tree | 0d62e7a10d30491f8b00ff476a8c2ab8a488b807 /src/libbsc/handover_decision.c | |
parent | 3b8dc575144eaae6240d0e6725151218824767b8 (diff) |
mscsplit: various preparations to separate MSC from BSC
Disable large parts of the code that depend on BSC presence. The code sections
disabled by #if BEFORE_MSCSPLIT shall be modified or dropped in the course of
adding the A-interface.
Don't set msg->lchan nor msg->dst.
Don't use lchan in libmsc.
Decouple lac from bts.
Prepare entry/exit point for MSC -> BSC and MSC -> RNC communication:
Add msc_ifaces.[hc], a_iface.c, with a general msc_tx_dtap() to redirect to
different interfaces depending on the actual subscriber connection.
While iu_tx() is going to be functional fairly soon, the a_tx() is going to be
just a dummy for some time (see comment).
Add Iu specific fields in gsm_subscriber_connection: the UE connection pointer
and an indicator for the Integrity Protection status on Iu (to be fully
implemented in later commits).
Add lac member to gsm_subscriber_connection, to allow decoupling from
bts->location_area_code. The conn->lac will actually be set in iu.c in an
upcoming commit ("add iucs.[hc]").
move to libcommon-cs: gsm48_extract_mi(), gsm48_paging_extract_mi().
libmsc: duplicate gsm0808 / gsm48 functions (towards BSC).
In osmo-nitb, libmsc would directly call the functions on the BSC level, not
always via the bsc_api. When separating libmsc from libbsc, some functions are
missing from the linkage.
Hence duplicate these functions to libmsc, add an msc_ prefix for clarity, also
add a _tx to gsm0808_cipher_mode():
* add msc_gsm0808_tx_cipher_mode() (dummy/stub)
* add msc_gsm48_tx_mm_serv_ack()
* add msc_gsm48_tx_mm_serv_rej()
Call these from libmsc instead of
* gsm0808_cipher_mode()
* gsm48_tx_mm_serv_ack()
* gsm48_tx_mm_serv_rej()
Also add a comment related to msc_gsm0808_tx_cipher_mode() in two places.
Remove internal RTP streaming code; OsmoNITB supported that, but for OsmoMSC,
this will be done with an external MGCP gateway.
Remove LCHAN_MODIFY from internal MNCC state machine.
Temporarily disable all paging to be able to link libmsc without libbsc.
Skip the paging part of channel_test because the paging is now disabled.
Employ fake paging shims in order for msc_vlr_tests to still work.
msc_compl_l3(): publish in .h, tweak return value. Use new libmsc enum values
for return val, to avoid dependency on libbsc headers. Make callable from
other scopes: publish in osmo_msc.h and remove 'static' in osmo_msc.c
add gsm_encr to subscr_conn
move subscr_request to gsm_subscriber.h
subscr_request_channel() -> subscr_request_conn()
move to libmsc: osmo_stats_vty_add_cmds()
gsm_04_08: remove apply_codec_restrictions()
gsm0408_test: use NULL for root ctx
move to libbsc: gsm_bts_neighbor()
move to libbsc: lchan_next_meas_rep()
move vty config for t3212 to network level (periodic lu)
remove unneccessary linking from some tests
remove handle_abisip_signal()
abis_rsl.c: don't use libvlr from libbsc
gsm_subscriber_connection: put the LAC here, so that it is available without
accessing conn->bts. In bsc_api.c, place this lac in conn for the sake of
transition: Iu and A will use this new field to pass the LAC around, but in a
completely separate OsmoBSC this is not actually needed. It can be removed
again from osmo-bsc.git when the time has come.
Siemens MRPCI: completely drop sending the MRPCI messages for now, they shall
be added in osmo-bsc once the A-Interface code has settled. See OS#2389.
Related: OS#1845 OS#2257 OS#2389
Change-Id: Id3705236350d5f69e447046b0a764bbabc3d493c
Diffstat (limited to 'src/libbsc/handover_decision.c')
-rw-r--r-- | src/libbsc/handover_decision.c | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/src/libbsc/handover_decision.c b/src/libbsc/handover_decision.c index 0f07bcac6..8d7e047b7 100644 --- a/src/libbsc/handover_decision.c +++ b/src/libbsc/handover_decision.c @@ -33,6 +33,27 @@ #include <openbsc/handover.h> #include <osmocom/gsm/gsm_utils.h> +/* Get reference to a neighbor cell on a given BCCH ARFCN */ +static struct gsm_bts *gsm_bts_neighbor(const struct gsm_bts *bts, + uint16_t arfcn, uint8_t bsic) +{ + struct gsm_bts *neigh; + /* FIXME: use some better heuristics here to determine which cell + * using this ARFCN really is closest to the target cell. For + * now we simply assume that each ARFCN will only be used by one + * cell */ + + llist_for_each_entry(neigh, &bts->network->bts_list, list) { + /* FIXME: this is probably returning the same bts again!? */ + if (neigh->c0->arfcn == arfcn && + neigh->bsic == bsic) + return neigh; + } + + return NULL; +} + + /* issue handover to a cell identified by ARFCN and BSIC */ static int handover_to_arfcn_bsic(struct gsm_lchan *lchan, uint16_t arfcn, uint8_t bsic) |