From: Soeren Apel <redacted>
Date: Sun, 16 Aug 2020 19:09:11 +0000 (+0200)
Subject: Implement single sample value getters
X-Git-Url: https://sigrok.org/gitaction?a=commitdiff_plain;h=27ff2925665ce9c916d68c637827095e27b99ee7;p=pulseview.git

Implement single sample value getters
---

diff --git a/pv/data/analogsegment.cpp b/pv/data/analogsegment.cpp
index e6f9626c..57901309 100644
--- a/pv/data/analogsegment.cpp
+++ b/pv/data/analogsegment.cpp
@@ -96,6 +96,16 @@ void AnalogSegment::append_interleaved_samples(const float *data,
 			prev_sample_count + 1, prev_sample_count + 1);
 }
 
+float AnalogSegment::get_sample(int64_t sample_num) const
+{
+	assert(sample_num >= 0);
+	assert(sample_num <= (int64_t)sample_count_);
+
+	lock_guard<recursive_mutex> lock(mutex_);  // Because of free_unused_memory()
+
+	return *((const float*)get_raw_sample(sample_num));
+}
+
 void AnalogSegment::get_samples(int64_t start_sample, int64_t end_sample,
 	float* dest) const
 {
diff --git a/pv/data/analogsegment.hpp b/pv/data/analogsegment.hpp
index 846837ce..63317043 100644
--- a/pv/data/analogsegment.hpp
+++ b/pv/data/analogsegment.hpp
@@ -81,6 +81,7 @@ public:
 	void append_interleaved_samples(const float *data,
 		size_t sample_count, size_t stride);
 
+	float get_sample(int64_t sample_num) const;
 	void get_samples(int64_t start_sample, int64_t end_sample, float* dest) const;
 
 	const pair<float, float> get_min_max() const;
diff --git a/pv/data/segment.cpp b/pv/data/segment.cpp
index 2bac0062..1dfdefd4 100644
--- a/pv/data/segment.cpp
+++ b/pv/data/segment.cpp
@@ -211,6 +211,20 @@ void Segment::append_samples(void* data, uint64_t samples)
 	sample_count_ += samples;
 }
 
+const uint8_t* Segment::get_raw_sample(uint64_t sample_num) const
+{
+	assert(sample_num <= sample_count_);
+
+	uint64_t chunk_num = (sample_num * unit_size_) / chunk_size_;
+	uint64_t chunk_offs = (sample_num * unit_size_) % chunk_size_;
+
+	lock_guard<recursive_mutex> lock(mutex_);  // Because of free_unused_memory()
+
+	const uint8_t* chunk = data_chunks_[chunk_num];
+
+	return chunk + chunk_offs;
+}
+
 void Segment::get_raw_samples(uint64_t start, uint64_t count,
 	uint8_t* dest) const
 {
@@ -219,13 +233,13 @@ void Segment::get_raw_samples(uint64_t start, uint64_t count,
 	assert(count > 0);
 	assert(dest != nullptr);
 
-	lock_guard<recursive_mutex> lock(mutex_);
-
 	uint8_t* dest_ptr = dest;
 
 	uint64_t chunk_num = (start * unit_size_) / chunk_size_;
 	uint64_t chunk_offs = (start * unit_size_) % chunk_size_;
 
+	lock_guard<recursive_mutex> lock(mutex_);  // Because of free_unused_memory()
+
 	while (count > 0) {
 		const uint8_t* chunk = data_chunks_[chunk_num];
 
diff --git a/pv/data/segment.hpp b/pv/data/segment.hpp
index 8465949c..9bdc17dd 100644
--- a/pv/data/segment.hpp
+++ b/pv/data/segment.hpp
@@ -25,12 +25,12 @@
 
 #include <mutex>
 #include <thread>
-#include <vector>
+#include <deque>
 
 #include <QObject>
 
 using std::recursive_mutex;
-using std::vector;
+using std::deque;
 
 namespace SegmentTest {
 struct SmallSize8Single;
@@ -84,6 +84,7 @@ public:
 protected:
 	void append_single_sample(void *data);
 	void append_samples(void *data, uint64_t samples);
+	const uint8_t* get_raw_sample(uint64_t sample_num) const;
 	void get_raw_samples(uint64_t start, uint64_t count, uint8_t *dest) const;
 
 	SegmentDataIterator* begin_sample_iteration(uint64_t start);
@@ -94,7 +95,7 @@ protected:
 
 	uint32_t segment_id_;
 	mutable recursive_mutex mutex_;
-	vector<uint8_t*> data_chunks_;
+	deque<uint8_t*> data_chunks_;
 	uint8_t* current_chunk_;
 	uint64_t used_samples_, unused_samples_;
 	uint64_t sample_count_;
diff --git a/pv/data/signalbase.cpp b/pv/data/signalbase.cpp
index 7d420ac7..fb687244 100644
--- a/pv/data/signalbase.cpp
+++ b/pv/data/signalbase.cpp
@@ -574,7 +574,9 @@ void SignalBase::convert_single_segment_range(AnalogSegment *asegment,
 
 		// Create sigrok::Analog instance
 		float *asamples = new float[ConversionBlockSize];
+		assert(asamples);
 		uint8_t *lsamples = new uint8_t[ConversionBlockSize];
+		assert(lsamples);
 
 		vector<shared_ptr<sigrok::Channel> > channels;
 		if (channel_)