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