]> sigrok.org Git - pulseview.git/blobdiff - pv/data/mathsignal.cpp
Session: Fix issue #67 by improving error handling
[pulseview.git] / pv / data / mathsignal.cpp
index 24df0e71985b3688aa3d1953e323e13084d24d32..adb27131e6d43bc00a89e788cf398c07ed57229a 100644 (file)
@@ -37,18 +37,24 @@ using std::unique_lock;
 namespace pv {
 namespace data {
 
+#define MATH_ERR_NONE           0
+#define MATH_ERR_EMPTY_EXPR     1
+#define MATH_ERR_EXPRESSION     2
+#define MATH_ERR_INVALID_SIGNAL 3
+#define MATH_ERR_ENABLE         4
+
 const int64_t MathSignal::ChunkLength = 256 * 1024;
 
 
 template<typename T>
-struct sig_sample : public exprtk::igeneric_function<T>
+struct fnc_sample : public exprtk::igeneric_function<T>
 {
        typedef typename exprtk::igeneric_function<T>::parameter_list_t parameter_list_t;
        typedef typename exprtk::igeneric_function<T>::generic_type generic_type;
        typedef typename generic_type::scalar_view scalar_t;
        typedef typename generic_type::string_view string_t;
 
-       sig_sample(MathSignal& owner) :
+       fnc_sample(MathSignal& owner) :
                exprtk::igeneric_function<T>("ST"),  // Require channel name and sample number
                owner_(owner),
                sig_data(nullptr)
@@ -63,10 +69,16 @@ struct sig_sample : public exprtk::igeneric_function<T>
                const std::string str_sig_name = to_str(exprtk_sig_name);
                const double sample_num = exprtk_sample_num();
 
+               if (sample_num < 0)
+                       return 0;
+
                if (!sig_data)
                        sig_data = owner_.signal_from_name(str_sig_name);
 
-               assert(sig_data);
+               if (!sig_data)
+                       // There doesn't actually exist a signal with that name
+                       return 0;
+
                owner_.update_signal_sample(sig_data, current_segment, sample_num);
 
                return T(sig_data->sample_value);
@@ -84,12 +96,12 @@ MathSignal::MathSignal(pv::Session &session) :
        use_custom_sample_rate_(false),
        use_custom_sample_count_(false),
        expression_(""),
-       error_message_(""),
+       error_type_(MATH_ERR_NONE),
        exprtk_unknown_symbol_table_(nullptr),
        exprtk_symbol_table_(nullptr),
        exprtk_expression_(nullptr),
        exprtk_parser_(nullptr),
-       fnc_sig_sample_(nullptr)
+       fnc_sample_(nullptr)
 {
        uint32_t sig_idx = session_.get_next_signal_index(MathChannel);
        set_name(QString(tr("Math%1")).arg(sig_idx));
@@ -99,20 +111,17 @@ MathSignal::MathSignal(pv::Session &session) :
 
        connect(&session_, SIGNAL(capture_state_changed(int)),
                this, SLOT(on_capture_state_changed(int)));
-       connect(&session_, SIGNAL(data_received()),
-               this, SLOT(on_data_received()));
 }
 
 MathSignal::~MathSignal()
 {
        reset_generation();
-
-       if (fnc_sig_sample_)
-               delete fnc_sig_sample_;
 }
 
 void MathSignal::save_settings(QSettings &settings) const
 {
+       SignalBase::save_settings(settings);
+
        settings.setValue("expression", expression_);
 
        settings.setValue("custom_sample_rate", (qulonglong)custom_sample_rate_);
@@ -123,6 +132,8 @@ void MathSignal::save_settings(QSettings &settings) const
 
 void MathSignal::restore_settings(QSettings &settings)
 {
+       SignalBase::restore_settings(settings);
+
        if (settings.contains("expression"))
                expression_ = settings.value("expression").toString();
 
@@ -139,11 +150,6 @@ void MathSignal::restore_settings(QSettings &settings)
                use_custom_sample_count_ = settings.value("use_custom_sample_count").toBool();
 }
 
-QString MathSignal::error_message() const
-{
-       return error_message_;
-}
-
 QString MathSignal::get_expression() const
 {
        return expression_;
@@ -156,11 +162,14 @@ void MathSignal::set_expression(QString expression)
        begin_generation();
 }
 
-void MathSignal::set_error_message(QString msg)
+void MathSignal::set_error(uint8_t type, QString msg)
 {
+       error_type_ = type;
        error_message_ = msg;
        // TODO Emulate noquote()
-       qDebug().nospace() << name() << ": " << msg << "(Expression: '" << expression_ << "')";
+       qDebug().nospace() << name() << ": " << msg << "(Expression: '" + expression_ + "')";
+
+       error_message_changed(msg);
 }
 
 uint64_t MathSignal::get_working_sample_count(uint32_t segment_id) const
@@ -201,7 +210,7 @@ uint64_t MathSignal::get_working_sample_count(uint32_t segment_id) const
        return result;
 }
 
-void MathSignal::update_completeness(uint32_t segment_id)
+void MathSignal::update_completeness(uint32_t segment_id, uint64_t output_sample_count)
 {
        bool output_complete = true;
 
@@ -224,9 +233,19 @@ void MathSignal::update_completeness(uint32_t segment_id)
                        }
 
                        const shared_ptr<AnalogSegment> segment = analog_segments.at(segment_id);
-                       if (!segment->is_complete())
+                       if (!segment->is_complete()) {
+                               output_complete = false;
+                               continue;
+                       }
+
+                       if (output_sample_count < segment->get_sample_count())
                                output_complete = false;
                }
+       } else {
+               // We're done when we generated as many samples as the stopped session is long
+               if ((session_.get_capture_state() != Session::Stopped) ||
+                       (output_sample_count < session_.get_segment_sample_count(segment_id)))
+                       output_complete = false;
        }
 
        if (output_complete)
@@ -264,16 +283,19 @@ void MathSignal::reset_generation()
                exprtk_unknown_symbol_table_ = nullptr;
        }
 
-       if (fnc_sig_sample_) {
-               delete fnc_sig_sample_;
-               fnc_sig_sample_ = nullptr;
+       if (fnc_sample_) {
+               delete fnc_sample_;
+               fnc_sample_ = nullptr;
        }
 
        if (!error_message_.isEmpty()) {
-               error_message_ = QString();
+               error_message_.clear();
+               error_type_ = MATH_ERR_NONE;
                // TODO Emulate noquote()
                qDebug().nospace() << name() << ": Error cleared";
        }
+
+       generation_chunk_size_ = ChunkLength;
 }
 
 void MathSignal::begin_generation()
@@ -281,16 +303,25 @@ void MathSignal::begin_generation()
        reset_generation();
 
        if (expression_.isEmpty()) {
-               set_error_message(tr("No expression defined, nothing to do"));
+               set_error(MATH_ERR_EMPTY_EXPR, tr("No expression defined, nothing to do"));
                return;
        }
 
-       fnc_sig_sample_ = new sig_sample<double>(*this);
+       disconnect(&session_, SIGNAL(data_received()), this, SLOT(on_data_received()));
+
+       for (const shared_ptr<SignalBase>& sb : session_.signalbases()) {
+               if (sb->analog_data())
+                       disconnect(sb->analog_data().get(), nullptr, this, SLOT(on_data_received()));
+               disconnect(sb.get(), nullptr, this, SLOT(on_enabled_changed()));
+       }
+
+       fnc_sample_ = new fnc_sample<double>(*this);
 
        exprtk_unknown_symbol_table_ = new exprtk::symbol_table<double>();
 
        exprtk_symbol_table_ = new exprtk::symbol_table<double>();
-       exprtk_symbol_table_->add_function("sig_sample", *fnc_sig_sample_);
+       exprtk_symbol_table_->add_constant("T", 1 / session_.get_samplerate());
+       exprtk_symbol_table_->add_function("sample", *fnc_sample_);
        exprtk_symbol_table_->add_variable("t", exprtk_current_time_);
        exprtk_symbol_table_->add_variable("s", exprtk_current_sample_);
        exprtk_symbol_table_->add_constants();
@@ -303,7 +334,25 @@ void MathSignal::begin_generation()
        exprtk_parser_->enable_unknown_symbol_resolver();
 
        if (!exprtk_parser_->compile(expression_.toStdString(), *exprtk_expression_)) {
-               set_error_message(tr("Error in expression"));
+               QString error_details;
+               size_t error_count = exprtk_parser_->error_count();
+
+               for (size_t i = 0; i < error_count; i++) {
+                       typedef exprtk::parser_error::type error_t;
+                       error_t error = exprtk_parser_->get_error(i);
+                       exprtk::parser_error::update_error(error, expression_.toStdString());
+
+                       QString error_detail = tr("%1 at line %2, column %3: %4");
+                       if ((error_count > 1) && (i < (error_count - 1)))
+                               error_detail += "\n";
+
+                       error_details += error_detail \
+                               .arg(exprtk::parser_error::to_str(error.mode).c_str()) \
+                               .arg(error.line_no) \
+                               .arg(error.column_no) \
+                               .arg(error.diagnostic.c_str());
+               }
+               set_error(MATH_ERR_EXPRESSION, error_details);
        } else {
                // Resolve unknown scalars to signals and add them to the input signal list
                vector<string> unknowns;
@@ -312,27 +361,38 @@ void MathSignal::begin_generation()
                        signal_data* sig_data = signal_from_name(unknown);
                        const shared_ptr<SignalBase> signal = (sig_data) ? (sig_data->sb) : nullptr;
                        if (!signal || (!signal->analog_data())) {
-                               set_error_message(QString(tr("%1 isn't a valid analog signal")).arg(
-                                       QString::fromStdString(unknown)));
+                               set_error(MATH_ERR_INVALID_SIGNAL, QString(tr("\"%1\" isn't a valid analog signal")) \
+                                       .arg(QString::fromStdString(unknown)));
                        } else
                                sig_data->ref = &(exprtk_unknown_symbol_table_->variable_ref(unknown));
                }
        }
 
+       QString disabled_signals;
+       if (!all_input_signals_enabled(disabled_signals) && error_message_.isEmpty())
+               set_error(MATH_ERR_ENABLE,
+                       tr("No data will be generated as %1 must be enabled").arg(disabled_signals));
+
        if (error_message_.isEmpty()) {
+               // Connect to the session data notification if we have no input signals
+               if (input_signals_.empty())
+                       connect(&session_, SIGNAL(data_received()),     this, SLOT(on_data_received()));
+
                gen_interrupt_ = false;
                gen_thread_ = std::thread(&MathSignal::generation_proc, this);
        }
 }
 
-void MathSignal::generate_samples(uint32_t segment_id, const uint64_t start_sample,
+uint64_t MathSignal::generate_samples(uint32_t segment_id, const uint64_t start_sample,
        const int64_t sample_count)
 {
+       uint64_t count = 0;
+
        shared_ptr<Analog> analog = dynamic_pointer_cast<Analog>(data_);
        shared_ptr<AnalogSegment> segment = analog->analog_segments().at(segment_id);
 
        // Keep the math functions segment IDs in sync
-       fnc_sig_sample_->current_segment = segment_id;
+       fnc_sample_->current_segment = segment_id;
 
        const double sample_rate = data_->get_samplerate();
 
@@ -351,17 +411,24 @@ void MathSignal::generate_samples(uint32_t segment_id, const uint64_t start_samp
                double value = exprtk_expression_->value();
                sample_data[i] = value;
                exprtk_current_sample_ += 1;
+               count++;
+
+               // If during the evaluation of the expression it was found that this
+               // math signal itself is being accessed, the chunk size was reduced
+               // to 1, which means we must stop after this sample we just generated
+               if (generation_chunk_size_ == 1)
+                       break;
        }
 
-       segment->append_interleaved_samples(sample_data, sample_count, 1);
+       segment->append_interleaved_samples(sample_data, count, 1);
 
        delete[] sample_data;
+
+       return count;
 }
 
 void MathSignal::generation_proc()
 {
-       uint32_t segment_id = 0;
-
        // Don't do anything until we have a valid sample rate
        do {
                if (use_custom_sample_rate_)
@@ -378,6 +445,7 @@ void MathSignal::generation_proc()
        if (gen_interrupt_)
                return;
 
+       uint32_t segment_id = 0;
        shared_ptr<Analog> analog = analog_data();
 
        // Create initial analog segment
@@ -396,45 +464,47 @@ void MathSignal::generation_proc()
 
                // Process the samples if necessary...
                if (samples_to_process > 0) {
-                       const uint64_t chunk_sample_count = ChunkLength;
-
                        uint64_t processed_samples = 0;
                        do {
                                const uint64_t start_sample = output_sample_count + processed_samples;
-                               const uint64_t sample_count =
-                                       min(samples_to_process - processed_samples,     chunk_sample_count);
+                               uint64_t sample_count =
+                                       min(samples_to_process - processed_samples,     generation_chunk_size_);
 
-                               generate_samples(segment_id, start_sample, sample_count);
+                               sample_count = generate_samples(segment_id, start_sample, sample_count);
                                processed_samples += sample_count;
 
                                // Notify consumers of this signal's data
-                               // TODO Does this work when a conversion is active?
                                samples_added(segment_id, start_sample, start_sample + processed_samples);
                        } while (!gen_interrupt_ && (processed_samples < samples_to_process));
                }
 
-               if (samples_to_process == 0) {
-                       update_completeness(segment_id);
+               update_completeness(segment_id, output_sample_count);
 
-                       if (segment_id < session_.get_highest_segment_id()) {
+               if (output_segment->is_complete() && (segment_id < session_.get_highest_segment_id())) {
                                // Process next segment
                                segment_id++;
 
                                output_segment =
                                        make_shared<AnalogSegment>(*analog.get(), segment_id, analog->get_samplerate());
                                analog->push_segment(output_segment);
-                       } else {
-                               // All segments have been processed, wait for more input
-                               unique_lock<mutex> gen_input_lock(input_mutex_);
-                               gen_input_cond_.wait(gen_input_lock);
-                       }
                }
 
+               if (!gen_interrupt_ && (samples_to_process == 0)) {
+                       // Wait for more input
+                       unique_lock<mutex> gen_input_lock(input_mutex_);
+                       gen_input_cond_.wait(gen_input_lock);
+               }
        } while (!gen_interrupt_);
 }
 
 signal_data* MathSignal::signal_from_name(const std::string& name)
 {
+       // If the expression contains the math signal itself, we must add every sample to
+       // the output segment immediately so that it can be accessed
+       const QString sig_name = QString::fromStdString(name);
+       if (sig_name == this->name())
+               generation_chunk_size_ = 1;
+
        // Look up signal in the map and if it doesn't exist yet, add it for future use
 
        auto element = input_signals_.find(name);
@@ -443,20 +513,29 @@ signal_data* MathSignal::signal_from_name(const std::string& name)
                return &(element->second);
        } else {
                const vector< shared_ptr<SignalBase> > signalbases = session_.signalbases();
-               const QString sig_name = QString::fromStdString(name);
 
                for (const shared_ptr<SignalBase>& sb : signalbases)
                        if (sb->name() == sig_name) {
                                if (!sb->analog_data())
                                        continue;
 
+                               connect(sb->analog_data().get(), SIGNAL(samples_added(SharedPtrToSegment, uint64_t, uint64_t)),
+                                       this, SLOT(on_data_received()));
                                connect(sb->analog_data().get(), SIGNAL(segment_completed()),
                                        this, SLOT(on_data_received()));
 
+                               connect(sb.get(), SIGNAL(enabled_changed(bool)),
+                                       this, SLOT(on_enabled_changed()));
+
                                return &(input_signals_.insert({name, signal_data(sb)}).first->second);
                        }
        }
 
+       // If we reach this point, no valid signal was found with the supplied name
+       if (error_type_ == MATH_ERR_NONE)
+               set_error(MATH_ERR_INVALID_SIGNAL, QString(tr("\"%1\" isn't a valid analog signal")) \
+                       .arg(QString::fromStdString(name)));
+
        return nullptr;
 }
 
@@ -477,27 +556,45 @@ void MathSignal::update_signal_sample(signal_data* sig_data, uint32_t segment_id
        const shared_ptr<AnalogSegment> segment = analog->analog_segments().at(segment_id);
 
        sig_data->sample_num = sample_num;
-       sig_data->sample_value = segment->get_sample(sample_num);
 
-       // We only have a reference if this signal is used as a scalar,
+       if (sample_num < segment->get_sample_count())
+               sig_data->sample_value = segment->get_sample(sample_num);
+       else
+               sig_data->sample_value = 0;
+
+       // We only have a reference if this signal is used as a scalar;
        // if it's used by a function, it's null
        if (sig_data->ref)
                *(sig_data->ref) = sig_data->sample_value;
 }
 
+bool MathSignal::all_input_signals_enabled(QString &disabled_signals) const
+{
+       bool all_enabled = true;
+
+       disabled_signals.clear();
+
+       for (auto input_signal : input_signals_) {
+               const shared_ptr<SignalBase>& sb = input_signal.second.sb;
+
+               if (!sb->enabled()) {
+                       all_enabled = false;
+                       disabled_signals += disabled_signals.isEmpty() ?
+                               sb->name() : ", " + sb->name();
+               }
+       }
+
+       return all_enabled;
+}
+
 void MathSignal::on_capture_state_changed(int state)
 {
        if (state == Session::Running)
                begin_generation();
 
-       if (state == Session::Stopped) {
-               // If we have input signals, we use those as the indicators
-               if (input_signals_.empty()) {
-                       shared_ptr<Analog> analog = analog_data();
-                       if (!analog->analog_segments().empty())
-                               analog->analog_segments().back()->set_complete();
-               }
-       }
+       // Make sure we don't miss any input samples, just in case
+       if (state == Session::Stopped)
+               gen_input_cond_.notify_one();
 }
 
 void MathSignal::on_data_received()
@@ -505,5 +602,18 @@ void MathSignal::on_data_received()
        gen_input_cond_.notify_one();
 }
 
+void MathSignal::on_enabled_changed()
+{
+       QString disabled_signals;
+       if (!all_input_signals_enabled(disabled_signals) &&
+               ((error_type_ == MATH_ERR_NONE) || (error_type_ == MATH_ERR_ENABLE)))
+               set_error(MATH_ERR_ENABLE,
+                       tr("No data will be generated as %1 must be enabled").arg(disabled_signals));
+       else if (disabled_signals.isEmpty() && (error_type_ == MATH_ERR_ENABLE)) {
+               error_type_ = MATH_ERR_NONE;
+               error_message_.clear();
+       }
+}
+
 } // namespace data
 } // namespace pv