libosmocore/include/osmocom
Pau Espin b5551eec33 gsm: [ABI BREAK] Support CellId SAI, change CellId CGI-PS id number
Those are available in 3GPP TS 48.008 version 16.0.0 Release 16, section
3.2.2.17 Cell Identifier. It can be seen that we have a collision
between the osmocom non-standard format and the SAI standard one.

This is because CGI-PS is not really a TS 48.008 Cell Identifier, but only
specified in TS 48.018 and has no ID number assigned. The CGI-PS was
added there because the whole osmo-bsc neighbour configuration works
with CellIds to manage neighbours, so it felt natural to extend the APIs
to also provide means to use CGI-PS format (TS 48.018 even refers 48.008
existance and mentions there's no explicit ID).

At the time this Cell Identifier was added, the firstly available number
(11) was taken, which was of course a really bad idea since newer
versions of the spec can at some point use it, which is the case if one
checks for instance TS 48.008 Release 16 SAI Cell Id.

There no perfect way to fix this bad decision at the time, but the
CGI-PS is only used in osmo-bsc and only for RIM related purposes, so by
changing the ID of CELL_IDENT_WHOLE_GLOBAL_PS, we only break RIM under
some specific CIs being used, and when an osmo-bsc is built against
older libosmocore and then used at runtime against a newer libosmocore
(which should be rare).
Hence, the downside is acceptable, and by moving the new ID number to be
ouside of the spec proto TS 48.008 range (4 bits), we make sure we don't
have the same problem again in the future.

Related: SYS#5838
Fixes: ca33a71ca8
Change-Id: Id25e563febdb7640174540136225f399515a0089
2022-02-16 17:59:23 +01:00
..
codec codec: add missing osmo_amr_type_name function. 2021-08-23 15:44:00 +02:00
coding gsm0503_parity: Fix compilation with gcc-10 2020-04-20 18:18:50 +02:00
core core/utils.h: make use of OSMO_LIKELY in OSMO_ASSERT 2022-02-09 10:05:25 +00:00
crypt include: add enum for UTRAN cipher 2021-11-11 09:02:24 +00:00
ctrl ports.h: add osmo-pfcp-tool ports 2022-01-21 00:55:51 +01:00
gprs include/: Adapt some headers to match contrib/struct_endianess.py format 2021-12-22 13:57:48 +01:00
gsm gsm: [ABI BREAK] Support CellId SAI, change CellId CGI-PS id number 2022-02-16 17:59:23 +01:00
sim treewide: remove FSF address 2021-12-14 12:44:03 +01:00
usb treewide: remove FSF address 2021-12-14 12:44:03 +01:00
vty ports.h: add osmo-pfcp-tool ports 2022-01-21 00:55:51 +01:00