Currently most offsets are hard-coded which makes it difficult to
access the data units and their headers when padding has to be taken
into account. These offset are already provided by the
gprs_rlc_data_info_init_ul/dl functions.
Change the encoder/decoder to use these values.
Note that some assumptions (bit alignment) are still present in the
code and checked by assertions.
Sponsored-by: On-Waves ehf
Currently the RBB is used and passed directly to the window handling
methods. For EGPRS a more abstract bitvec is derived from the messages
and will passed around instead.
Add a similar function for GPRS so that the same window handling can
be used for GPRS and EGPRS.
Sponsored-by: On-Waves ehf
Currently CRBB bitmaps are ignored if they are present.
This commit enables the decoding.
Note that this requires osmo_t4_decode in libosmocore.
Sponsored-by: On-Waves ehf
Currently only uncompressed bitmaps (URBB) are supported in
PACKET UPLINK ACK/NACK messages.
Extend decode_egprs_acknack_bits to decode compressed bitmaps (CRBB),
too.
Note that this code is only active, if the macro WITH_CRBB_DECODING
is defined.
Sponsored-by: On-Waves ehf
Currently this message is ignored.
Support decoding and handling of this message. Use a bitvec for the
decoder that just represents a BSN sequence without any encoding
details (first bit -> first BSN). Return the corresponding BSN range
(snsmod(bsn_begin + bits_in_bitvec) = bsn_end), so snsmod(bsn_end-1)
is the last BSN if there is at least 1. If bsn_begin == bsn_end, no
BSNs has been added.
Note that this bitvec is not yet used for RBB handling. It just calls
the old rcvd_dl_ack with a faked (all bits are 1) RBB map.
Sponsored-by: On-Waves ehf
These struct names are more specific than necessary. They are used
for GPRS (uplink) already. In downlink direction, only a few fields
will be added to the header struct. Add addition,
gprs_rlc_ul_header_egprs does not map directly to an encoded
header, like many other 'header' structs do.
Change the names to fit both modes and both directions:
gprs_rlc_ul_header_egprs -> gprs_rlc_data_info
gprs_rlc_ul_data_block_info -> gprs_rlc_data_block_info
Sponsored-by: On-Waves ehf
Use a signed integer instead of an unsigned one for num_chunks
which can set to a negative value on error.
Ensure that chunks is not dereferenced if it is NULL. In fact
that will not happen currently, since num_chunks is now always
<= 0 if chunks == NULL.
Fixes: Coverity CID 1347433, 1347434, 1347435
Sponsored-by: On-Waves ehf
This commit adds new RLC block decoder functions that support both
GPRS and EGPRS. The code path is selected based on the value of the
GprsCodingScheme cs object.
- rlc_parse_ul_data_header
parses the header of an RLC data block including the E and FBI/TI
flags (currently supported CS-1 - CS-4, MCS-1 - MCS-4).
- rlc_copy_to_aligned_buffer
copies an RLC data unit to a byte aligned buffer and returns
the unit's length.
- rlc_get_data_aligned
is a convenience wrapper around rlc_copy_to_aligned_buffer
that avoids copying if the data unit is already byte aligned.
Sponsored-by: On-Waves ehf
The EGPRS MS class ist contained in the MS_RA_capability information.
Its presence indicates, that the MS is able (and willing) to use
EGPRS.
This commit implements basic support for retrieving, storing, and
showing it in the VTY. The information is stored in the MS object.
Sponsored-by: On-Waves ehf
Move the parsing of the bitbmap out of the TBF code into Decoding.
Move the updating of the V_B into the V_B class. Add some comments
about handling the mod_sns, mod_sns_half parameters by using template
code.
Move the method into the PDCH. Extract the finding of TLLI into a
new class called Decoding. Move the assemble and forward LLC frames
into the TBF as it is poking in the internals of the TBF.
Jacob Erlbeck
Daniel Willmann