Refactor the Uplink RLC header parsing function

Parsing the uplink data header for GPRS and EGPRS header type 3
is handled in separate functions.
This patch will enhance modularity of the code.
This commit is contained in:
Bhargava Abhyankar 2016-03-22 18:42:30 +05:30 committed by Harald Welte
parent 5a5d2b7a27
commit e44383baa4
2 changed files with 84 additions and 65 deletions

View File

@ -344,74 +344,14 @@ void Decoding::extract_rbb(const struct bitvec *rbb, char *show_rbb)
int Decoding::rlc_parse_ul_data_header(struct gprs_rlc_data_info *rlc,
const uint8_t *data, GprsCodingScheme cs)
{
const struct gprs_rlc_ul_header_egprs_3 *egprs3;
const struct rlc_ul_header *gprs;
unsigned int e_ti_header;
unsigned int cur_bit = 0;
int punct, punct2, with_padding, cps;
unsigned int offs;
switch(cs.headerTypeData()) {
case GprsCodingScheme::HEADER_GPRS_DATA:
gprs = static_cast<struct rlc_ul_header *>
((void *)data);
gprs_rlc_data_info_init_ul(rlc, cs, false);
rlc->r = gprs->r;
rlc->si = gprs->si;
rlc->tfi = gprs->tfi;
rlc->cps = 0;
rlc->rsb = 0;
rlc->num_data_blocks = 1;
rlc->block_info[0].cv = gprs->cv;
rlc->block_info[0].pi = gprs->pi;
rlc->block_info[0].bsn = gprs->bsn;
rlc->block_info[0].e = gprs->e;
rlc->block_info[0].ti = gprs->ti;
rlc->block_info[0].spb = 0;
cur_bit += rlc->data_offs_bits[0];
/* skip data area */
cur_bit += cs.maxDataBlockBytes() * 8;
case GprsCodingScheme::HEADER_GPRS_DATA :
cur_bit = rlc_parse_ul_data_header_gprs(rlc, data, cs);
break;
case GprsCodingScheme::HEADER_EGPRS_DATA_TYPE_3:
egprs3 = static_cast<struct gprs_rlc_ul_header_egprs_3 *>
((void *)data);
cps = (egprs3->cps_a << 0) | (egprs3->cps_b << 2);
gprs_rlc_mcs_cps_decode(cps, cs, &punct, &punct2, &with_padding);
gprs_rlc_data_info_init_ul(rlc, cs, with_padding);
rlc->r = egprs3->r;
rlc->si = egprs3->si;
rlc->tfi = (egprs3->tfi_a << 0) | (egprs3->tfi_b << 2);
rlc->cps = cps;
rlc->rsb = egprs3->rsb;
rlc->num_data_blocks = 1;
rlc->block_info[0].cv = egprs3->cv;
rlc->block_info[0].pi = egprs3->pi;
rlc->block_info[0].spb = egprs3->spb;
rlc->block_info[0].bsn =
(egprs3->bsn1_a << 0) | (egprs3->bsn1_b << 5);
cur_bit += rlc->data_offs_bits[0] - 2;
offs = rlc->data_offs_bits[0] / 8;
OSMO_ASSERT(rlc->data_offs_bits[0] % 8 == 1);
e_ti_header = (data[offs-1] + (data[offs] << 8)) >> 7;
rlc->block_info[0].e = !!(e_ti_header & 0x01);
rlc->block_info[0].ti = !!(e_ti_header & 0x02);
cur_bit += 2;
/* skip data area */
cur_bit += cs.maxDataBlockBytes() * 8;
case GprsCodingScheme::HEADER_EGPRS_DATA_TYPE_3 :
cur_bit = rlc_parse_ul_data_header_egprs_type_3(rlc, data, cs);
break;
case GprsCodingScheme::HEADER_EGPRS_DATA_TYPE_1:
case GprsCodingScheme::HEADER_EGPRS_DATA_TYPE_2:
/* TODO: Support both header types */
@ -426,6 +366,78 @@ int Decoding::rlc_parse_ul_data_header(struct gprs_rlc_data_info *rlc,
return cur_bit;
}
int Decoding::rlc_parse_ul_data_header_egprs_type_3(
struct gprs_rlc_data_info *rlc,
const uint8_t *data,
const GprsCodingScheme &cs)
{
int punct, punct2, with_padding, cps;
unsigned int e_ti_header, offs, cur_bit = 0;
const struct gprs_rlc_ul_header_egprs_3 *egprs3;
egprs3 = static_cast < struct gprs_rlc_ul_header_egprs_3 * >
((void *)data);
cps = (egprs3->cps_a << 0) | (egprs3->cps_b << 2);
gprs_rlc_mcs_cps_decode(cps, cs, &punct, &punct2, &with_padding);
gprs_rlc_data_info_init_ul(rlc, cs, with_padding);
rlc->r = egprs3->r;
rlc->si = egprs3->si;
rlc->tfi = (egprs3->tfi_a << 0) | (egprs3->tfi_b << 2);
rlc->cps = cps;
rlc->rsb = egprs3->rsb;
rlc->num_data_blocks = 1;
rlc->block_info[0].cv = egprs3->cv;
rlc->block_info[0].pi = egprs3->pi;
rlc->block_info[0].spb = egprs3->spb;
rlc->block_info[0].bsn =
(egprs3->bsn1_a << 0) | (egprs3->bsn1_b << 5);
cur_bit += rlc->data_offs_bits[0] - 2;
offs = rlc->data_offs_bits[0] / 8;
OSMO_ASSERT(rlc->data_offs_bits[0] % 8 == 1);
e_ti_header = (data[offs-1] + (data[offs] << 8)) >> 7;
rlc->block_info[0].e = !!(e_ti_header & 0x01);
rlc->block_info[0].ti = !!(e_ti_header & 0x02);
cur_bit += 2;
/* skip data area */
cur_bit += cs.maxDataBlockBytes() * 8;
return cur_bit;
}
int Decoding::rlc_parse_ul_data_header_gprs(struct gprs_rlc_data_info *rlc,
const uint8_t *data, const GprsCodingScheme &cs)
{
const struct rlc_ul_header *gprs;
unsigned int cur_bit = 0;
gprs = static_cast < struct rlc_ul_header * >
((void *)data);
gprs_rlc_data_info_init_ul(rlc, cs, false);
rlc->r = gprs->r;
rlc->si = gprs->si;
rlc->tfi = gprs->tfi;
rlc->cps = 0;
rlc->rsb = 0;
rlc->num_data_blocks = 1;
rlc->block_info[0].cv = gprs->cv;
rlc->block_info[0].pi = gprs->pi;
rlc->block_info[0].bsn = gprs->bsn;
rlc->block_info[0].e = gprs->e;
rlc->block_info[0].ti = gprs->ti;
rlc->block_info[0].spb = 0;
cur_bit += rlc->data_offs_bits[0];
/* skip data area */
cur_bit += cs.maxDataBlockBytes() * 8;
return cur_bit;
}
/**
* \brief Copy LSB bitstream RLC data block to byte aligned buffer.
*

View File

@ -43,7 +43,14 @@ public:
static void extract_rbb(const uint8_t *rbb, char *extracted_rbb);
static void extract_rbb(const struct bitvec *rbb, char *show_rbb);
static int rlc_parse_ul_data_header_egprs_type_3(
struct gprs_rlc_data_info *rlc,
const uint8_t *data,
const GprsCodingScheme &cs);
static int rlc_parse_ul_data_header_gprs(
struct gprs_rlc_data_info *rlc,
const uint8_t *data,
const GprsCodingScheme &cs);
static int rlc_parse_ul_data_header(struct gprs_rlc_data_info *rlc,
const uint8_t *data, GprsCodingScheme cs);
static unsigned int rlc_copy_to_aligned_buffer(