2 * This file is part of the PulseView project.
4 * Copyright (C) 2017 Soeren Apel <soeren@apelpie.net>
5 * Copyright (C) 2012 Joel Holdsworth <joel@airwebreathe.org.uk>
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, see <http://www.gnu.org/licenses/>.
21 #include "segment.hpp"
29 using std::lock_guard;
30 using std::recursive_mutex;
36 Segment::Segment(uint64_t samplerate, unsigned int unit_size) :
39 samplerate_(samplerate),
42 lock_guard<recursive_mutex> lock(mutex_);
43 assert(unit_size_ > 0);
45 // Determine the number of samples we can fit in one chunk
46 // without exceeding MaxChunkSize
47 chunk_size_ = std::min(MaxChunkSize,
48 (MaxChunkSize / unit_size_) * unit_size_);
50 // Create the initial chunk
51 current_chunk_ = new uint8_t[chunk_size_];
52 data_chunks_.push_back(current_chunk_);
54 unused_samples_ = chunk_size_ / unit_size_;
59 lock_guard<recursive_mutex> lock(mutex_);
61 for (uint8_t* chunk : data_chunks_)
65 uint64_t Segment::get_sample_count() const
67 lock_guard<recursive_mutex> lock(mutex_);
71 const pv::util::Timestamp& Segment::start_time() const
76 double Segment::samplerate() const
81 void Segment::set_samplerate(double samplerate)
83 samplerate_ = samplerate;
86 unsigned int Segment::unit_size() const
91 void Segment::free_unused_memory()
93 lock_guard<recursive_mutex> lock(mutex_);
95 // No more data will come in, so re-create the last chunk accordingly
96 uint8_t* resized_chunk = new uint8_t[used_samples_ * unit_size_];
97 memcpy(resized_chunk, current_chunk_, used_samples_ * unit_size_);
99 delete[] current_chunk_;
100 current_chunk_ = resized_chunk;
102 data_chunks_.pop_back();
103 data_chunks_.push_back(resized_chunk);
106 void Segment::append_single_sample(void *data)
108 lock_guard<recursive_mutex> lock(mutex_);
110 // There will always be space for at least one sample in
111 // the current chunk, so we do not need to test for space
113 memcpy(current_chunk_ + (used_samples_ * unit_size_),
118 if (unused_samples_ == 0) {
119 current_chunk_ = new uint8_t[chunk_size_];
120 data_chunks_.push_back(current_chunk_);
122 unused_samples_ = chunk_size_ / unit_size_;
128 void Segment::append_samples(void* data, uint64_t samples)
130 lock_guard<recursive_mutex> lock(mutex_);
132 if (unused_samples_ >= samples) {
133 // All samples fit into the current chunk
134 memcpy(current_chunk_ + (used_samples_ * unit_size_),
135 data, (samples * unit_size_));
136 used_samples_ += samples;
137 unused_samples_ -= samples;
139 // Only a part of the samples fit, split data up between chunks
140 memcpy(current_chunk_ + (used_samples_ * unit_size_),
141 data, (unused_samples_ * unit_size_));
142 const uint64_t remaining_samples = samples - unused_samples_;
144 // If we're out of memory, this will throw std::bad_alloc
145 current_chunk_ = new uint8_t[chunk_size_];
146 data_chunks_.push_back(current_chunk_);
147 memcpy(current_chunk_, (uint8_t*)data + (unused_samples_ * unit_size_),
148 (remaining_samples * unit_size_));
150 used_samples_ = remaining_samples;
151 unused_samples_ = (chunk_size_ / unit_size_) - remaining_samples;
154 if (unused_samples_ == 0) {
155 // If we're out of memory, this will throw std::bad_alloc
156 current_chunk_ = new uint8_t[chunk_size_];
157 data_chunks_.push_back(current_chunk_);
159 unused_samples_ = chunk_size_ / unit_size_;
162 sample_count_ += samples;
165 uint8_t* Segment::get_raw_samples(uint64_t start, uint64_t count) const
167 assert(start < sample_count_);
168 assert(start + count <= sample_count_);
171 lock_guard<recursive_mutex> lock(mutex_);
173 uint8_t* dest = new uint8_t[count * unit_size_];
174 uint8_t* dest_ptr = dest;
176 uint64_t chunk_num = (start * unit_size_) / chunk_size_;
177 uint64_t chunk_offs = (start * unit_size_) % chunk_size_;
180 const uint8_t* chunk = data_chunks_[chunk_num];
182 uint64_t copy_size = std::min(count * unit_size_,
183 chunk_size_ - chunk_offs);
185 memcpy(dest_ptr, chunk + chunk_offs, copy_size);
187 dest_ptr += copy_size;
188 count -= (copy_size / unit_size_);
197 SegmentRawDataIterator* Segment::begin_raw_sample_iteration(uint64_t start) const
199 SegmentRawDataIterator* it = new SegmentRawDataIterator;
201 assert(start < sample_count_);
203 it->sample_index = start;
204 it->chunk_num = (start * unit_size_) / chunk_size_;
205 it->chunk_offs = (start * unit_size_) % chunk_size_;
206 it->chunk = data_chunks_[it->chunk_num];
207 it->value = it->chunk + it->chunk_offs;
212 void Segment::continue_raw_sample_iteration(SegmentRawDataIterator* it, uint64_t increase) const
214 lock_guard<recursive_mutex> lock(mutex_);
216 if (it->sample_index > sample_count_)
218 // Fail gracefully if we are asked to deliver data we don't have
221 it->sample_index += increase;
222 it->chunk_offs += (increase * unit_size_);
225 if (it->chunk_offs > (chunk_size_ - 1)) {
227 it->chunk_offs -= chunk_size_;
228 it->chunk = data_chunks_[it->chunk_num];
231 it->value = it->chunk + it->chunk_offs;
234 void Segment::end_raw_sample_iteration(SegmentRawDataIterator* it) const