pv/data/mathsignal.cpp

   1 /*
   2  * This file is part of the PulseView project.
   3  *
   4  * Copyright (C) 2020 Soeren Apel <soeren@apelpie.net>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include <limits>
  21
  22 #include <QDebug>
  23
  24 #include "mathsignal.hpp"
  25
  26 #include <extdef.h>
  27 #include <pv/globalsettings.hpp>
  28 #include <pv/session.hpp>
  29 #include <pv/data/analogsegment.hpp>
  30 #include <pv/data/signalbase.hpp>
  31
  32 using std::dynamic_pointer_cast;
  33 using std::make_shared;
  34 using std::min;
  35 using std::unique_lock;
  36
  37 namespace pv {
  38 namespace data {
  39
  40 #define MATH_ERR_NONE           0
  41 #define MATH_ERR_EMPTY_EXPR     1
  42 #define MATH_ERR_EXPRESSION     2
  43 #define MATH_ERR_INVALID_SIGNAL 3
  44 #define MATH_ERR_ENABLE         4
  45
  46 const int64_t MathSignal::ChunkLength = 256 * 1024;
  47
  48
  49 template<typename T>
  50 struct sig_sample : public exprtk::igeneric_function<T>
  51 {
  52         typedef typename exprtk::igeneric_function<T>::parameter_list_t parameter_list_t;
  53         typedef typename exprtk::igeneric_function<T>::generic_type generic_type;
  54         typedef typename generic_type::scalar_view scalar_t;
  55         typedef typename generic_type::string_view string_t;
  56
  57         sig_sample(MathSignal& owner) :
  58                 exprtk::igeneric_function<T>("ST"),  // Require channel name and sample number
  59                 owner_(owner),
  60                 sig_data(nullptr)
  61         {
  62         }
  63
  64         T operator()(parameter_list_t parameters)
  65         {
  66                 const string_t exprtk_sig_name = string_t(parameters[0]);
  67                 const scalar_t exprtk_sample_num = scalar_t(parameters[1]);
  68
  69                 const std::string str_sig_name = to_str(exprtk_sig_name);
  70                 const double sample_num = exprtk_sample_num();
  71
  72                 if (!sig_data)
  73                         sig_data = owner_.signal_from_name(str_sig_name);
  74
  75                 assert(sig_data);
  76                 owner_.update_signal_sample(sig_data, current_segment, sample_num);
  77
  78                 return T(sig_data->sample_value);
  79         }
  80
  81         MathSignal& owner_;
  82         uint32_t current_segment;
  83         signal_data* sig_data;
  84 };
  85
  86
  87 MathSignal::MathSignal(pv::Session &session) :
  88         SignalBase(nullptr, SignalBase::MathChannel),
  89         session_(session),
  90         use_custom_sample_rate_(false),
  91         use_custom_sample_count_(false),
  92         expression_(""),
  93         error_type_(MATH_ERR_NONE),
  94         exprtk_unknown_symbol_table_(nullptr),
  95         exprtk_symbol_table_(nullptr),
  96         exprtk_expression_(nullptr),
  97         exprtk_parser_(nullptr),
  98         fnc_sig_sample_(nullptr)
  99 {
 100         uint32_t sig_idx = session_.get_next_signal_index(MathChannel);
 101         set_name(QString(tr("Math%1")).arg(sig_idx));
 102         set_color(AnalogSignalColors[(sig_idx - 1) % countof(AnalogSignalColors)]);
 103
 104         set_data(std::make_shared<data::Analog>());
 105
 106         connect(&session_, SIGNAL(capture_state_changed(int)),
 107                 this, SLOT(on_capture_state_changed(int)));
 108 }
 109
 110 MathSignal::~MathSignal()
 111 {
 112         reset_generation();
 113
 114         if (fnc_sig_sample_)
 115                 delete fnc_sig_sample_;
 116 }
 117
 118 void MathSignal::save_settings(QSettings &settings) const
 119 {
 120         SignalBase::save_settings(settings);
 121
 122         settings.setValue("expression", expression_);
 123
 124         settings.setValue("custom_sample_rate", (qulonglong)custom_sample_rate_);
 125         settings.setValue("custom_sample_count", (qulonglong)custom_sample_count_);
 126         settings.setValue("use_custom_sample_rate", use_custom_sample_rate_);
 127         settings.setValue("use_custom_sample_count", use_custom_sample_count_);
 128 }
 129
 130 void MathSignal::restore_settings(QSettings &settings)
 131 {
 132         SignalBase::restore_settings(settings);
 133
 134         if (settings.contains("expression"))
 135                 expression_ = settings.value("expression").toString();
 136
 137         if (settings.contains("custom_sample_rate"))
 138                 custom_sample_rate_ = settings.value("custom_sample_rate").toULongLong();
 139
 140         if (settings.contains("custom_sample_count"))
 141                 custom_sample_count_ = settings.value("custom_sample_count").toULongLong();
 142
 143         if (settings.contains("use_custom_sample_rate"))
 144                 use_custom_sample_rate_ = settings.value("use_custom_sample_rate").toBool();
 145
 146         if (settings.contains("use_custom_sample_count"))
 147                 use_custom_sample_count_ = settings.value("use_custom_sample_count").toBool();
 148 }
 149
 150 QString MathSignal::get_expression() const
 151 {
 152         return expression_;
 153 }
 154
 155 void MathSignal::set_expression(QString expression)
 156 {
 157         expression_ = expression;
 158
 159         begin_generation();
 160 }
 161
 162 void MathSignal::set_error(uint8_t type, QString msg)
 163 {
 164         error_type_ = type;
 165         error_message_ = msg;
 166         // TODO Emulate noquote()
 167         qDebug().nospace() << name() << ": " << msg << "(Expression: '" + expression_ + "')";
 168
 169         error_message_changed(msg);
 170 }
 171
 172 uint64_t MathSignal::get_working_sample_count(uint32_t segment_id) const
 173 {
 174         // The working sample count is the highest sample number for
 175         // which all used signals have data available, so go through all
 176         // channels and use the lowest overall sample count of the segment
 177
 178         int64_t result = std::numeric_limits<int64_t>::max();
 179
 180         if (use_custom_sample_count_)
 181                 // A custom sample count implies that only one segment will be created
 182                 result = (segment_id == 0) ? custom_sample_count_ : 0;
 183         else {
 184                 if (input_signals_.size() > 0) {
 185                         for (auto input_signal : input_signals_) {
 186                                 const shared_ptr<SignalBase>& sb = input_signal.second.sb;
 187
 188                                 shared_ptr<Analog> a = sb->analog_data();
 189                                 auto analog_segments = a->analog_segments();
 190
 191                                 if (analog_segments.size() == 0) {
 192                                         result = 0;
 193                                         continue;
 194                                 }
 195
 196                                 const uint32_t highest_segment_id = (analog_segments.size() - 1);
 197                                 if (segment_id > highest_segment_id)
 198                                         continue;
 199
 200                                 const shared_ptr<AnalogSegment> segment = analog_segments.at(segment_id);
 201                                 result = min(result, (int64_t)segment->get_sample_count());
 202                         }
 203                 } else
 204                         result = session_.get_segment_sample_count(segment_id);
 205         }
 206
 207         return result;
 208 }
 209
 210 void MathSignal::update_completeness(uint32_t segment_id, uint64_t output_sample_count)
 211 {
 212         bool output_complete = true;
 213
 214         if (input_signals_.size() > 0) {
 215                 for (auto input_signal : input_signals_) {
 216                         const shared_ptr<SignalBase>& sb = input_signal.second.sb;
 217
 218                         shared_ptr<Analog> a = sb->analog_data();
 219                         auto analog_segments = a->analog_segments();
 220
 221                         if (analog_segments.size() == 0) {
 222                                 output_complete = false;
 223                                 continue;
 224                         }
 225
 226                         const uint32_t highest_segment_id = (analog_segments.size() - 1);
 227                         if (segment_id > highest_segment_id) {
 228                                 output_complete = false;
 229                                 continue;
 230                         }
 231
 232                         const shared_ptr<AnalogSegment> segment = analog_segments.at(segment_id);
 233                         if (!segment->is_complete()) {
 234                                 output_complete = false;
 235                                 continue;
 236                         }
 237
 238                         if (output_sample_count < segment->get_sample_count())
 239                                 output_complete = false;
 240                 }
 241         } else {
 242                 // We're done when we generated as many samples as the stopped session is long
 243                 if ((session_.get_capture_state() != Session::Stopped) ||
 244                         (output_sample_count < session_.get_segment_sample_count(segment_id)))
 245                         output_complete = false;
 246         }
 247
 248         if (output_complete)
 249                 analog_data()->analog_segments().at(segment_id)->set_complete();
 250 }
 251
 252 void MathSignal::reset_generation()
 253 {
 254         if (gen_thread_.joinable()) {
 255                 gen_interrupt_ = true;
 256                 gen_input_cond_.notify_one();
 257                 gen_thread_.join();
 258         }
 259
 260         data_->clear();
 261         input_signals_.clear();
 262
 263         if (exprtk_parser_) {
 264                 delete exprtk_parser_;
 265                 exprtk_parser_ = nullptr;
 266         }
 267
 268         if (exprtk_expression_) {
 269                 delete exprtk_expression_;
 270                 exprtk_expression_ = nullptr;
 271         }
 272
 273         if (exprtk_symbol_table_) {
 274                 delete exprtk_symbol_table_;
 275                 exprtk_symbol_table_ = nullptr;
 276         }
 277
 278         if (exprtk_unknown_symbol_table_) {
 279                 delete exprtk_unknown_symbol_table_;
 280                 exprtk_unknown_symbol_table_ = nullptr;
 281         }
 282
 283         if (fnc_sig_sample_) {
 284                 delete fnc_sig_sample_;
 285                 fnc_sig_sample_ = nullptr;
 286         }
 287
 288         if (!error_message_.isEmpty()) {
 289                 error_message_.clear();
 290                 error_type_ = MATH_ERR_NONE;
 291                 // TODO Emulate noquote()
 292                 qDebug().nospace() << name() << ": Error cleared";
 293         }
 294 }
 295
 296 void MathSignal::begin_generation()
 297 {
 298         reset_generation();
 299
 300         if (expression_.isEmpty()) {
 301                 set_error(MATH_ERR_EMPTY_EXPR, tr("No expression defined, nothing to do"));
 302                 return;
 303         }
 304
 305         disconnect(this, SLOT(on_data_received()));
 306         disconnect(this, SLOT(on_enabled_changed()));
 307
 308         fnc_sig_sample_ = new sig_sample<double>(*this);
 309
 310         exprtk_unknown_symbol_table_ = new exprtk::symbol_table<double>();
 311
 312         exprtk_symbol_table_ = new exprtk::symbol_table<double>();
 313         exprtk_symbol_table_->add_function("sig_sample", *fnc_sig_sample_);
 314         exprtk_symbol_table_->add_variable("t", exprtk_current_time_);
 315         exprtk_symbol_table_->add_variable("s", exprtk_current_sample_);
 316         exprtk_symbol_table_->add_constants();
 317
 318         exprtk_expression_ = new exprtk::expression<double>();
 319         exprtk_expression_->register_symbol_table(*exprtk_unknown_symbol_table_);
 320         exprtk_expression_->register_symbol_table(*exprtk_symbol_table_);
 321
 322         exprtk_parser_ = new exprtk::parser<double>();
 323         exprtk_parser_->enable_unknown_symbol_resolver();
 324
 325         if (!exprtk_parser_->compile(expression_.toStdString(), *exprtk_expression_)) {
 326                 QString error_details;
 327                 size_t error_count = exprtk_parser_->error_count();
 328
 329                 for (size_t i = 0; i < error_count; i++) {
 330                         typedef exprtk::parser_error::type error_t;
 331                         error_t error = exprtk_parser_->get_error(i);
 332                         exprtk::parser_error::update_error(error, expression_.toStdString());
 333
 334                         QString error_detail = tr("%1 at line %2, column %3: %4");
 335                         if ((error_count > 1) && (i < (error_count - 1)))
 336                                 error_detail += "\n";
 337
 338                         error_details += error_detail \
 339                                 .arg(exprtk::parser_error::to_str(error.mode).c_str()) \
 340                                 .arg(error.line_no) \
 341                                 .arg(error.column_no) \
 342                                 .arg(error.diagnostic.c_str());
 343                 }
 344                 set_error(MATH_ERR_EXPRESSION, error_details);
 345         } else {
 346                 // Resolve unknown scalars to signals and add them to the input signal list
 347                 vector<string> unknowns;
 348                 exprtk_unknown_symbol_table_->get_variable_list(unknowns);
 349                 for (string& unknown : unknowns) {
 350                         signal_data* sig_data = signal_from_name(unknown);
 351                         const shared_ptr<SignalBase> signal = (sig_data) ? (sig_data->sb) : nullptr;
 352                         if (!signal || (!signal->analog_data())) {
 353                                 set_error(MATH_ERR_INVALID_SIGNAL, QString(tr("%1 isn't a valid analog signal")) \
 354                                         .arg(QString::fromStdString(unknown)));
 355                         } else
 356                                 sig_data->ref = &(exprtk_unknown_symbol_table_->variable_ref(unknown));
 357                 }
 358         }
 359
 360         QString disabled_signals;
 361         if (!all_input_signals_enabled(disabled_signals) && error_message_.isEmpty())
 362                 set_error(MATH_ERR_ENABLE,
 363                         tr("No data will be generated as %1 must be enabled").arg(disabled_signals));
 364
 365         if (error_message_.isEmpty()) {
 366                 // Connect to the session data notification if we have no input signals
 367                 if (input_signals_.empty())
 368                         connect(&session_, SIGNAL(data_received()),
 369                                 this, SLOT(on_data_received()));
 370
 371                 gen_interrupt_ = false;
 372                 gen_thread_ = std::thread(&MathSignal::generation_proc, this);
 373         }
 374 }
 375
 376 void MathSignal::generate_samples(uint32_t segment_id, const uint64_t start_sample,
 377         const int64_t sample_count)
 378 {
 379         shared_ptr<Analog> analog = dynamic_pointer_cast<Analog>(data_);
 380         shared_ptr<AnalogSegment> segment = analog->analog_segments().at(segment_id);
 381
 382         // Keep the math functions segment IDs in sync
 383         fnc_sig_sample_->current_segment = segment_id;
 384
 385         const double sample_rate = data_->get_samplerate();
 386
 387         exprtk_current_sample_ = start_sample;
 388
 389         float *sample_data = new float[sample_count];
 390
 391         for (int64_t i = 0; i < sample_count; i++) {
 392                 exprtk_current_time_ = exprtk_current_sample_ / sample_rate;
 393
 394                 for (auto& entry : input_signals_) {
 395                         signal_data* sig_data  = &(entry.second);
 396                         update_signal_sample(sig_data, segment_id, exprtk_current_sample_);
 397                 }
 398
 399                 double value = exprtk_expression_->value();
 400                 sample_data[i] = value;
 401                 exprtk_current_sample_ += 1;
 402         }
 403
 404         segment->append_interleaved_samples(sample_data, sample_count, 1);
 405
 406         delete[] sample_data;
 407 }
 408
 409 void MathSignal::generation_proc()
 410 {
 411         // Don't do anything until we have a valid sample rate
 412         do {
 413                 if (use_custom_sample_rate_)
 414                         data_->set_samplerate(custom_sample_rate_);
 415                 else
 416                         data_->set_samplerate(session_.get_samplerate());
 417
 418                 if (data_->get_samplerate() == 1) {
 419                         unique_lock<mutex> gen_input_lock(input_mutex_);
 420                         gen_input_cond_.wait(gen_input_lock);
 421                 }
 422         } while ((!gen_interrupt_) && (data_->get_samplerate() == 1));
 423
 424         if (gen_interrupt_)
 425                 return;
 426
 427         uint32_t segment_id = 0;
 428         shared_ptr<Analog> analog = analog_data();
 429
 430         // Create initial analog segment
 431         shared_ptr<AnalogSegment> output_segment =
 432                 make_shared<AnalogSegment>(*analog.get(), segment_id, analog->get_samplerate());
 433         analog->push_segment(output_segment);
 434
 435         // Create analog samples
 436         do {
 437                 const uint64_t input_sample_count = get_working_sample_count(segment_id);
 438                 const uint64_t output_sample_count = output_segment->get_sample_count();
 439
 440                 const uint64_t samples_to_process =
 441                         (input_sample_count > output_sample_count) ?
 442                         (input_sample_count - output_sample_count) : 0;
 443
 444                 // Process the samples if necessary...
 445                 if (samples_to_process > 0) {
 446                         const uint64_t chunk_sample_count = ChunkLength;
 447
 448                         uint64_t processed_samples = 0;
 449                         do {
 450                                 const uint64_t start_sample = output_sample_count + processed_samples;
 451                                 const uint64_t sample_count =
 452                                         min(samples_to_process - processed_samples,     chunk_sample_count);
 453
 454                                 generate_samples(segment_id, start_sample, sample_count);
 455                                 processed_samples += sample_count;
 456
 457                                 // Notify consumers of this signal's data
 458                                 samples_added(segment_id, start_sample, start_sample + processed_samples);
 459                         } while (!gen_interrupt_ && (processed_samples < samples_to_process));
 460                 }
 461
 462                 update_completeness(segment_id, output_sample_count);
 463
 464                 if (output_segment->is_complete() && (segment_id < session_.get_highest_segment_id())) {
 465                                 // Process next segment
 466                                 segment_id++;
 467
 468                                 output_segment =
 469                                         make_shared<AnalogSegment>(*analog.get(), segment_id, analog->get_samplerate());
 470                                 analog->push_segment(output_segment);
 471                 }
 472
 473                 if (!gen_interrupt_ && (samples_to_process == 0)) {
 474                         // Wait for more input
 475                         unique_lock<mutex> gen_input_lock(input_mutex_);
 476                         gen_input_cond_.wait(gen_input_lock);
 477                 }
 478         } while (!gen_interrupt_);
 479 }
 480
 481 signal_data* MathSignal::signal_from_name(const std::string& name)
 482 {
 483         // Look up signal in the map and if it doesn't exist yet, add it for future use
 484
 485         auto element = input_signals_.find(name);
 486
 487         if (element != input_signals_.end()) {
 488                 return &(element->second);
 489         } else {
 490                 const vector< shared_ptr<SignalBase> > signalbases = session_.signalbases();
 491                 const QString sig_name = QString::fromStdString(name);
 492
 493                 for (const shared_ptr<SignalBase>& sb : signalbases)
 494                         if (sb->name() == sig_name) {
 495                                 if (!sb->analog_data())
 496                                         continue;
 497
 498                                 connect(sb->analog_data().get(), SIGNAL(samples_added(SharedPtrToSegment, uint64_t, uint64_t)),
 499                                         this, SLOT(on_data_received()));
 500                                 connect(sb->analog_data().get(), SIGNAL(segment_completed()),
 501                                         this, SLOT(on_data_received()));
 502
 503                                 connect(sb.get(), SIGNAL(enabled_changed(bool)),
 504                                         this, SLOT(on_enabled_changed()));
 505
 506                                 return &(input_signals_.insert({name, signal_data(sb)}).first->second);
 507                         }
 508         }
 509
 510         return nullptr;
 511 }
 512
 513 void MathSignal::update_signal_sample(signal_data* sig_data, uint32_t segment_id, uint64_t sample_num)
 514 {
 515         assert(sig_data);
 516
 517         // Update the value only if a different sample is requested
 518         if (sig_data->sample_num == sample_num)
 519                 return;
 520
 521         assert(sig_data->sb);
 522         const shared_ptr<pv::data::Analog> analog = sig_data->sb->analog_data();
 523         assert(analog);
 524
 525         assert(segment_id < analog->analog_segments().size());
 526
 527         const shared_ptr<AnalogSegment> segment = analog->analog_segments().at(segment_id);
 528
 529         sig_data->sample_num = sample_num;
 530         sig_data->sample_value = segment->get_sample(sample_num);
 531
 532         // We only have a reference if this signal is used as a scalar;
 533         // if it's used by a function, it's null
 534         if (sig_data->ref)
 535                 *(sig_data->ref) = sig_data->sample_value;
 536 }
 537
 538 bool MathSignal::all_input_signals_enabled(QString &disabled_signals) const
 539 {
 540         bool all_enabled = true;
 541
 542         disabled_signals.clear();
 543
 544         for (auto input_signal : input_signals_) {
 545                 const shared_ptr<SignalBase>& sb = input_signal.second.sb;
 546
 547                 if (!sb->enabled()) {
 548                         all_enabled = false;
 549                         disabled_signals += disabled_signals.isEmpty() ?
 550                                 sb->name() : ", " + sb->name();
 551                 }
 552         }
 553
 554         return all_enabled;
 555 }
 556
 557 void MathSignal::on_capture_state_changed(int state)
 558 {
 559         if (state == Session::Running)
 560                 begin_generation();
 561
 562         // Make sure we don't miss any input samples, just in case
 563         if (state == Session::Stopped)
 564                 gen_input_cond_.notify_one();
 565 }
 566
 567 void MathSignal::on_data_received()
 568 {
 569         gen_input_cond_.notify_one();
 570 }
 571
 572 void MathSignal::on_enabled_changed()
 573 {
 574         QString disabled_signals;
 575         if (!all_input_signals_enabled(disabled_signals) &&
 576                 ((error_type_ == MATH_ERR_NONE) || (error_type_ == MATH_ERR_ENABLE)))
 577                 set_error(MATH_ERR_ENABLE,
 578                         tr("No data will be generated as %1 must be enabled").arg(disabled_signals));
 579         else if (disabled_signals.isEmpty() && (error_type_ == MATH_ERR_ENABLE)) {
 580                 error_type_ = MATH_ERR_NONE;
 581                 error_message_.clear();
 582         }
 583 }
 584
 585 } // namespace data
 586 } // namespace pv