| /* |
| * Copyright (C) 2019 sysmocom - s.f.m.c. GmbH |
| * All Rights Reserved |
| * |
| * SPDX-License-Identifier: AGPL-3.0+ |
| * |
| * Author: Pau Espin Pedrol <pespin@sysmocom.de> |
| * |
| * 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/>. |
| * See the COPYING file in the main directory for details. |
| */ |
| |
| #include "proto_trxd.h" |
| |
| #include <osmocom/core/bits.h> |
| |
| static void trxd_fill_common(struct trxd_hdr_common *common, const struct trx_ul_burst_ind *bi, uint8_t version) |
| { |
| common->version = version & 0b1111; |
| common->reserved = 0; |
| common->tn = bi->tn; |
| osmo_store32be(bi->fn, &common->fn); |
| } |
| |
| static void trxd_fill_v0_specific(struct trxd_hdr_v0_specific *v0, const struct trx_ul_burst_ind *bi) |
| { |
| int toa_int; |
| |
| /* in 1/256 symbols, round to closest integer */ |
| toa_int = (int) (bi->toa * 256.0 + 0.5); |
| v0->rssi = bi->rssi; |
| osmo_store16be(toa_int, &v0->toa); |
| } |
| |
| static void trxd_fill_v1_specific(struct trxd_hdr_v1_specific *v1, const struct trx_ul_burst_ind *bi) |
| { |
| int16_t ci_int_cB; |
| |
| /* deciBels->centiBels, round to closest integer */ |
| ci_int_cB = (int16_t)((bi->ci * 10) + 0.5); |
| |
| v1->idle = !!bi->idle; |
| v1->modulation = (bi->modulation == MODULATION_GMSK) ? |
| TRXD_MODULATION_GMSK(bi->tss) : |
| TRXD_MODULATION_8PSK(bi->tss); |
| v1->tsc = bi->tsc; |
| osmo_store16be(ci_int_cB, &v1->ci); |
| } |
| |
| static void trxd_fill_burst_normalized255(uint8_t* soft_bits, const struct trx_ul_burst_ind *bi) |
| { |
| unsigned i; |
| for (i = 0; i < bi->nbits; i++) |
| soft_bits[i] = (char) round(bi->rx_burst[i] * 255.0); |
| } |
| |
| bool trxd_send_burst_ind_v0(size_t chan, int fd, const struct trx_ul_burst_ind *bi) { |
| int rc; |
| |
| /* v0 doesn't support idle frames, they are simply dropped, not sent */ |
| if(bi->idle) |
| return true; |
| |
| /* +2: Historically (OpenBTS times), two extra non-used bytes are sent appeneded to each burst */ |
| char buf[sizeof(struct trxd_hdr_v0) + bi->nbits + 2]; |
| struct trxd_hdr_v0* pkt = (struct trxd_hdr_v0*)buf; |
| |
| trxd_fill_common(&pkt->common, bi, 0); |
| trxd_fill_v0_specific(&pkt->v0, bi); |
| trxd_fill_burst_normalized255(&pkt->soft_bits[0], bi); |
| |
| /* +1: Historical reason. There's an uninitizalied byte in there: pkt->soft_bits[bi->nbits] */ |
| pkt->soft_bits[bi->nbits + 1] = '\0'; |
| |
| rc = write(fd, buf, sizeof(struct trxd_hdr_v0) + bi->nbits + 2); |
| if (rc <= 0) { |
| CLOGCHAN(chan, DMAIN, LOGL_NOTICE, "mDataSockets write(%d) failed: %d\n", fd, rc); |
| return false; |
| } |
| return true; |
| } |
| |
| bool trxd_send_burst_ind_v1(size_t chan, int fd, const struct trx_ul_burst_ind *bi) { |
| int rc; |
| size_t buf_len; |
| |
| buf_len = sizeof(struct trxd_hdr_v1); |
| if (!bi->idle) |
| buf_len += bi->nbits; |
| char buf[buf_len]; |
| |
| struct trxd_hdr_v1* pkt = (struct trxd_hdr_v1*)buf; |
| trxd_fill_common(&pkt->common, bi, 1); |
| trxd_fill_v0_specific(&pkt->v0, bi); |
| trxd_fill_v1_specific(&pkt->v1, bi); |
| |
| if (!bi->idle) |
| trxd_fill_burst_normalized255(&pkt->soft_bits[0], bi); |
| |
| rc = write(fd, buf, buf_len); |
| if (rc <= 0) { |
| CLOGCHAN(chan, DMAIN, LOGL_NOTICE, "mDataSockets write(%d) failed: %d\n", fd, rc); |
| return false; |
| } |
| return true; |
| } |