DecodeSignal: Rework samplerate handling

[pulseview.git] / pv / data / decodesignal.cpp

diff --git a/pv/data/decodesignal.cpp b/pv/data/decodesignal.cpp
index a7bcee59c78185c9cd0d0540ac299ed4143505d4..339c85dd01dd0305879bce1dc88d3fde6d8ec6e3 100644 (file)
--- a/pv/data/decodesignal.cpp
+++ b/pv/data/decodesignal.cpp
@@ -221,13 +221,6 @@ void DecodeSignal::begin_decode()
                }
        }
 
-       // TODO Currently we assume all channels have the same sample rate
-       auto any_channel = find_if(channels_.begin(), channels_.end(),
-               [](data::DecodeChannel ch) { return ch.assigned_signal; });
-       shared_ptr<LogicSegment> first_segment =
-                       any_channel->assigned_signal->logic_data()->logic_segments().front();
-       samplerate_ = first_segment->samplerate();
-
        // Free the logic data and its segment(s) if it needs to be updated
        if (logic_mux_data_invalid_)
                logic_mux_data_.reset();
@@ -240,12 +233,6 @@ void DecodeSignal::begin_decode()
                logic_mux_data_->push_segment(segment_);
        }
 
-       // Update the samplerate and start time
-       start_time_ = segment_->start_time();
-       samplerate_ = segment_->samplerate();
-       if (samplerate_ == 0.0)
-               samplerate_ = 1.0;
-
        // Make sure the logic output data is complete and up-to-date
        logic_mux_interrupt_ = false;
        logic_mux_thread_ = std::thread(&DecodeSignal::logic_mux_proc, this);
@@ -626,6 +613,37 @@ void DecodeSignal::logic_mux_proc()
        decode_input_cond_.notify_one();
 }
 
+void DecodeSignal::query_input_metadata()
+{
+       // Update the samplerate and start time because we cannot start
+       // the libsrd session without the current samplerate
+
+       // TODO Currently we assume all channels have the same sample rate
+       // and start time
+       bool samplerate_valid = false;
+
+       auto any_channel = find_if(channels_.begin(), channels_.end(),
+               [](data::DecodeChannel ch) { return ch.assigned_signal; });
+
+       shared_ptr<Logic> logic_data =
+               any_channel->assigned_signal->logic_data();
+
+       do {
+               if (!logic_data->logic_segments().empty()) {
+                       shared_ptr<LogicSegment> first_segment =
+                               any_channel->assigned_signal->logic_data()->logic_segments().front();
+                       start_time_ = first_segment->start_time();
+                       samplerate_ = first_segment->samplerate();
+                       if (samplerate_ > 0)
+                               samplerate_valid = true;
+               }
+
+               // Wait until input data is available or an interrupt was requested
+               unique_lock<mutex> input_wait_lock(input_mutex_);
+               decode_input_cond_.wait(input_wait_lock);
+       } while (!samplerate_valid && !decode_interrupt_);
+}
+
 void DecodeSignal::decode_data(
        const int64_t abs_start_samplenum, const int64_t sample_count)
 {
@@ -647,6 +665,7 @@ void DecodeSignal::decode_data(
                        delete[] chunk;
                        break;
                }
+
                delete[] chunk;
 
                {
@@ -658,6 +677,11 @@ void DecodeSignal::decode_data(
 
 void DecodeSignal::decode_proc()
 {
+       query_input_metadata();
+
+       if (decode_interrupt_)
+               return;
+
        start_srd_session();
 
        uint64_t sample_count;
@@ -683,7 +707,7 @@ void DecodeSignal::decode_proc()
                        // Make sure all annotations are known to the frontend
                        new_annotations();
 
-                       // Wait for new input data or an interrupt request
+                       // Wait for new input data or an interrupt was requested
                        unique_lock<mutex> input_wait_lock(input_mutex_);
                        decode_input_cond_.wait(input_wait_lock);
                }
@@ -692,37 +716,38 @@ void DecodeSignal::decode_proc()
 
 void DecodeSignal::start_srd_session()
 {
-       if (!srd_session_) {
-               // Create the session
-               srd_session_new(&srd_session_);
-               assert(srd_session_);
+       if (srd_session_)
+               stop_srd_session();
 
-               // Create the decoders
-               srd_decoder_inst *prev_di = nullptr;
-               for (const shared_ptr<decode::Decoder> &dec : stack_) {
-                       srd_decoder_inst *const di = dec->create_decoder_inst(srd_session_);
+       // Create the session
+       srd_session_new(&srd_session_);
+       assert(srd_session_);
 
-                       if (!di) {
-                               error_message_ = tr("Failed to create decoder instance");
-                               srd_session_destroy(srd_session_);
-                               return;
-                       }
-
-                       if (prev_di)
-                               srd_inst_stack(srd_session_, prev_di, di);
+       // Create the decoders
+       srd_decoder_inst *prev_di = nullptr;
+       for (const shared_ptr<decode::Decoder> &dec : stack_) {
+               srd_decoder_inst *const di = dec->create_decoder_inst(srd_session_);
 
-                       prev_di = di;
+               if (!di) {
+                       error_message_ = tr("Failed to create decoder instance");
+                       srd_session_destroy(srd_session_);
+                       return;
                }
 
-               // Start the session
-               srd_session_metadata_set(srd_session_, SRD_CONF_SAMPLERATE,
-                       g_variant_new_uint64(samplerate_));
-
-               srd_pd_output_callback_add(srd_session_, SRD_OUTPUT_ANN,
-                       DecodeSignal::annotation_callback, this);
+               if (prev_di)
+                       srd_inst_stack(srd_session_, prev_di, di);
 
-               srd_session_start(srd_session_);
+               prev_di = di;
        }
+
+       // Start the session
+       srd_session_metadata_set(srd_session_, SRD_CONF_SAMPLERATE,
+               g_variant_new_uint64(samplerate_));
+
+       srd_pd_output_callback_add(srd_session_, SRD_OUTPUT_ANN,
+               DecodeSignal::annotation_callback, this);
+
+       srd_session_start(srd_session_);
 }
 
 void DecodeSignal::stop_srd_session()