summaryrefslogtreecommitdiffstats
path: root/src/fig/FIG0_21.cpp
blob: 5855fb1ca8d3084332024732556c459d3f035c58 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
/*
   Copyright (C) 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010,
   2011, 2012 Her Majesty the Queen in Right of Canada (Communications
   Research Center Canada)

   Copyright (C) 2018
   Matthias P. Braendli, matthias.braendli@mpb.li
   */
/*
   This file is part of ODR-DabMux.

   ODR-DabMux is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as
   published by the Free Software Foundation, either version 3 of the
   License, or (at your option) any later version.

   ODR-DabMux 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 General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with ODR-DabMux.  If not, see <http://www.gnu.org/licenses/>.
*/

#include "fig/FIG0structs.h"
#include "fig/FIG0_21.h"
#include "utils.h"

using namespace std;

namespace FIC {

struct FIGtype0_21_header {
    // This was RegionId in EN 300 401 V1.4.1
    uint8_t rfaHigh;

    uint8_t length_fi:5;
    uint8_t rfaLow:3;
} PACKED;

struct FIGtype0_21_fi_list_header {
    uint8_t idHigh;

    uint8_t idLow;

    uint8_t length_freq_list:3;
    uint8_t continuity:1;
    uint8_t range_modulation:4;

    void setId(uint16_t id) {
        idHigh = id >> 8;
        idLow = id & 0xFF;
    }

    void addToLength(uint8_t increment) {
        const uint32_t newlen = length_freq_list + increment;
        if (newlen > 0x7) {
            throw logic_error("FI freq list too long: " + to_string(newlen));
        }
        length_freq_list = newlen;
    }
} PACKED;

struct FIGtype0_21_fi_dab_entry {
    uint8_t freqHigh:3;
    uint8_t control_field:5;

    uint8_t freqMid;

    uint8_t freqLow;

    void setFreq(uint32_t freq) {
        freqHigh = (freq >> 16) & 0x7;
        freqMid = (freq >> 8) & 0xff;
        freqLow = freq & 0xff;
    }
} PACKED;


FIG0_21::FIG0_21(FIGRuntimeInformation *rti) :
    m_rti(rti)
{
}

static size_t get_num_frequencies(
        std::vector<FrequencyInformation>::iterator fi)
{
    switch (fi->rm) {
        case RangeModulation::dab_ensemble:
            if (fi->fi_dab.frequencies.empty()) {
                throw std::logic_error("Empty DAB FI");
            }
            return fi->fi_dab.frequencies.size();
        case RangeModulation::fm_with_rds:
            if (fi->fi_fm.frequencies.empty()) {
                throw std::logic_error("Empty FM FI");
            }
            return fi->fi_fm.frequencies.size();
        case RangeModulation::amss:
            if (fi->fi_amss.frequencies.empty()) {
                throw std::logic_error("Empty AMSS FI");
            }
            return fi->fi_amss.frequencies.size();
        case RangeModulation::drm:
            if (fi->fi_drm.frequencies.empty()) {
                throw std::logic_error("Empty DRM FI");
            }
            return fi->fi_drm.frequencies.size();
    }
    throw logic_error("Unhandled get_num_frequencies");
}

FillStatus FIG0_21::fill(uint8_t *buf, size_t max_size)
{
#define FIG0_21_TRACE discard
    FillStatus fs;
    size_t remaining = max_size;
    auto ensemble = m_rti->ensemble;

    if (not m_initialised) {
        freqInfoFIG0_21 = ensemble->frequency_information.begin();
        fi_frequency_index = 0;

        if (freqInfoFIG0_21 != ensemble->frequency_information.end()) {
            m_last_oe = freqInfoFIG0_21->other_ensemble;
        }
        m_initialised = true;
    }

    FIGtype0* fig0 = nullptr;

    auto advance_loop = [&](void){
            if (fi_frequency_index == get_num_frequencies(freqInfoFIG0_21)) {
                ++freqInfoFIG0_21;
                fi_frequency_index = 0;
            }
        };

    for (; freqInfoFIG0_21 != ensemble->frequency_information.end();
            advance_loop()) {
        /* For better usage of FIC capacity, we want to transmit
         * frequency lists with
         * 2 DAB frequencies,
         * 7 FM frequencies,
         * 3 AM/DRM frequencies
         */

        // Check we have space for one frequency
        size_t required_fi_size = 2; // RegionId + length of FI list
        size_t list_entry_size = sizeof(struct FIGtype0_21_fi_list_header);
        switch (freqInfoFIG0_21->rm) {
            case RangeModulation::dab_ensemble:
                list_entry_size += 3;
                break;
            case RangeModulation::fm_with_rds:
                list_entry_size += 1;
                break;
            case RangeModulation::amss:
                list_entry_size += 1; // Id field 2
                list_entry_size += 2;
                break;
            case RangeModulation::drm:
                list_entry_size += 1; // Id field 2
                list_entry_size += 2;
                break;
        }
        required_fi_size += list_entry_size;

        const size_t required_size =
            sizeof(struct FIGtype0_21_header) + required_fi_size;

        if (m_last_oe != freqInfoFIG0_21->other_ensemble) {
            // Trigger resend of FIG0 when OE changes
            fig0 = nullptr;
            m_last_oe = freqInfoFIG0_21->other_ensemble;
            etiLog.level(FIG0_21_TRACE) << "FIG0_21::switch OE to " <<
                freqInfoFIG0_21->other_ensemble;
        }

        if (fig0 == nullptr) {
            if (remaining < 2 + required_size) {
                break;
            }
            fig0 = (FIGtype0*)buf;
            fig0->FIGtypeNumber = 0;
            fig0->Length = 1;

            // Database start or continuation flag, EN 300 401 Clause 5.2.2.1 part b)
            fig0->CN = (fi_frequency_index == 0 ? 0 : 1);
            fig0->OE = freqInfoFIG0_21->other_ensemble ? 1 : 0;
            fig0->PD = false;
            fig0->Extension = 21;

            buf += 2;
            remaining -= 2;
        }
        else if (remaining < required_size) {
            break;
        }

        etiLog.level(FIG0_21_TRACE) << "FIG0_21::loop " << freqInfoFIG0_21->uid << " " <<
            std::distance(ensemble->frequency_information.begin(), freqInfoFIG0_21) <<
            " freq entry " << fi_frequency_index;

        auto *fig0_21_header = (FIGtype0_21_header*)buf;
        fig0_21_header->rfaHigh = 0;
        fig0_21_header->rfaLow = 0;
        fig0_21_header->length_fi = sizeof(FIGtype0_21_fi_list_header);

        fig0->Length += sizeof(FIGtype0_21_header);
        buf          += sizeof(FIGtype0_21_header);
        remaining    -= sizeof(FIGtype0_21_header);

        auto *fi_list_header = (FIGtype0_21_fi_list_header*)buf;
        fig0->Length += sizeof(FIGtype0_21_fi_list_header);
        buf          += sizeof(FIGtype0_21_fi_list_header);
        remaining    -= sizeof(FIGtype0_21_fi_list_header);

        fi_list_header->continuity = freqInfoFIG0_21->continuity;
        fi_list_header->length_freq_list = 0;
        fi_list_header->range_modulation = static_cast<uint8_t>(freqInfoFIG0_21->rm);

        bool continue_loop = true;

        switch (freqInfoFIG0_21->rm) {
            case RangeModulation::dab_ensemble:
                fi_list_header->setId(freqInfoFIG0_21->fi_dab.eid);

                for (size_t num_inserted = 0, i = fi_frequency_index;
                        num_inserted < 2 and
                        i < freqInfoFIG0_21->fi_dab.frequencies.size();
                        num_inserted++, i++) {
                    if (remaining < 3) {
                        continue_loop = false;
                        break;
                    }

                    const auto& freq = freqInfoFIG0_21->fi_dab.frequencies.at(i);

                    auto *field = (FIGtype0_21_fi_dab_entry*)buf;
                    field->control_field = static_cast<uint8_t>(freq.control_field);
                    field->setFreq(static_cast<uint32_t>(
                                freq.frequency * 1000.0f / 16.0f));

                    fig0_21_header->length_fi += 3;
                    fi_list_header->addToLength(3);
                    fig0->Length += 3;
                    buf += 3;
                    remaining -= 3;
                    etiLog.level(FIG0_21_TRACE) << "FIG0_21::freq " <<
                        fi_frequency_index << " " << freq.frequency << " rem " << remaining;
                    fi_frequency_index++;
                }
                break;
            case RangeModulation::fm_with_rds:
                fi_list_header->setId(freqInfoFIG0_21->fi_fm.pi_code);

                for (size_t num_inserted = 0, i = fi_frequency_index;
                        num_inserted < 7 and
                        i < freqInfoFIG0_21->fi_fm.frequencies.size();
                        num_inserted++, i++) {
                    if (remaining < 1) {
                        continue_loop = false;
                        break;
                    }

                    const auto& freq = freqInfoFIG0_21->fi_fm.frequencies.at(i);
                    // RealFreq = 87.5 MHz + (F * 100kHz)
                    // => F = (RealFreq - 87.5 MHz) / 100kHz
                    // Do the whole calculation in kHz:
                    *buf = (freq * 1000.0f - 87500.0f) / 100.0f;

                    fig0_21_header->length_fi += 1;
                    fi_list_header->addToLength(1);
                    fig0->Length += 1;
                    buf += 1;
                    remaining -= 1;
                    fi_frequency_index++;
                }
                break;
            case RangeModulation::drm:
                fi_list_header->setId((freqInfoFIG0_21->fi_drm.drm_service_id) & 0xFFFF);

                if (remaining < 3) {
                    throw logic_error("Incorrect DRM FI size calculation");
                }

                // Id field 2
                *buf = (freqInfoFIG0_21->fi_drm.drm_service_id >> 16) & 0xFF;
                fig0_21_header->length_fi += 1;

                fi_list_header->addToLength(1);
                fig0->Length += 1;
                buf += 1;
                remaining -= 1;

                for (size_t num_inserted = 0, i = fi_frequency_index;
                        num_inserted < 3 and
                        i < freqInfoFIG0_21->fi_drm.frequencies.size();
                        num_inserted++, i++) {
                    if (remaining < 2) {
                        continue_loop = false;
                        break;
                    }

                    const auto& freq = freqInfoFIG0_21->fi_drm.frequencies.at(i);
                    uint16_t freq_field = static_cast<uint16_t>(freq * 1000.0f);
                    buf[0] = freq_field >> 8;
                    buf[1] = freq_field & 0xFF;

                    fi_list_header->addToLength(2);
                    fig0_21_header->length_fi += 2;
                    fig0->Length += 2;
                    buf += 2;
                    remaining -= 2;
                    fi_frequency_index++;
                }
                break;
            case RangeModulation::amss:
                fi_list_header->setId((freqInfoFIG0_21->fi_amss.amss_service_id) & 0xFFFF);

                if (remaining < 3) {
                    throw logic_error("Incorrect AMSS FI size calculation");
                }

                // Id field 2
                *buf = (freqInfoFIG0_21->fi_amss.amss_service_id >> 16) & 0xFF;
                fig0_21_header->length_fi += 1;

                fi_list_header->addToLength(1);
                fig0->Length += 1;
                buf += 1;
                remaining -= 1;

                for (size_t num_inserted = 0, i = fi_frequency_index;
                        num_inserted < 3 and
                        i < freqInfoFIG0_21->fi_amss.frequencies.size();
                        num_inserted++, i++) {
                    if (remaining < 2) {
                        continue_loop = false;
                        break;
                    }

                    const auto& freq = freqInfoFIG0_21->fi_amss.frequencies.at(i);
                    uint16_t freq_field = static_cast<uint16_t>(freq * 1000.0f);
                    buf[0] = freq_field >> 8;
                    buf[1] = freq_field & 0xFF;

                    fi_list_header->addToLength(2);
                    fig0_21_header->length_fi += 2;
                    fig0->Length += 2;
                    buf += 2;
                    remaining -= 2;
                    fi_frequency_index++;
                }
                break;
        } // switch (RM)

        etiLog.level(FIG0_21_TRACE) << "FIG0_21::end " <<
            (continue_loop ? "same " : "next ") << " len=" <<
            static_cast<size_t>(fig0->Length) << " rem=" << remaining <<
            " ********************************";

        if (not continue_loop) {
            // There is no more space left. The freqInfoFIG0_21 iterator
            // and fi_frequency_index save the position how to continue
            // next time we are called.
            break;
        }
    } // for over FI

    if (freqInfoFIG0_21 == ensemble->frequency_information.end()) {
        fs.complete_fig_transmitted = true;

        freqInfoFIG0_21 = ensemble->frequency_information.begin();
        fi_frequency_index = 0;
    }

    fs.num_bytes_written = max_size - remaining;
    return fs;
}

}