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::append_single_sample(void *data)
93 lock_guard<recursive_mutex> lock(mutex_);
95 // There will always be space for at least one sample in
96 // the current chunk, so we do not need to test for space
98 memcpy(current_chunk_ + (used_samples_ * unit_size_),
103 if (unused_samples_ == 0) {
104 current_chunk_ = new uint8_t[chunk_size_];
105 data_chunks_.push_back(current_chunk_);
107 unused_samples_ = chunk_size_ / unit_size_;
113 void Segment::append_samples(void* data, uint64_t samples)
115 lock_guard<recursive_mutex> lock(mutex_);
117 if (unused_samples_ >= samples) {
118 // All samples fit into the current chunk
119 memcpy(current_chunk_ + (used_samples_ * unit_size_),
120 data, (samples * unit_size_));
121 used_samples_ += samples;
122 unused_samples_ -= samples;
124 // Only a part of the samples fit, split data up between chunks
125 memcpy(current_chunk_ + (used_samples_ * unit_size_),
126 data, (unused_samples_ * unit_size_));
127 const uint64_t remaining_samples = samples - unused_samples_;
129 // If we're out of memory, this will throw std::bad_alloc
130 current_chunk_ = new uint8_t[chunk_size_];
131 data_chunks_.push_back(current_chunk_);
132 memcpy(current_chunk_, (uint8_t*)data + (unused_samples_ * unit_size_),
133 (remaining_samples * unit_size_));
135 used_samples_ = remaining_samples;
136 unused_samples_ = (chunk_size_ / unit_size_) - remaining_samples;
139 if (unused_samples_ == 0) {
140 // If we're out of memory, this will throw std::bad_alloc
141 current_chunk_ = new uint8_t[chunk_size_];
142 data_chunks_.push_back(current_chunk_);
144 unused_samples_ = chunk_size_ / unit_size_;
147 sample_count_ += samples;
150 uint8_t* Segment::get_raw_samples(uint64_t start, uint64_t count) const
152 assert(start < sample_count_);
153 assert(start + count <= sample_count_);
156 lock_guard<recursive_mutex> lock(mutex_);
158 uint8_t* dest = new uint8_t[count * unit_size_];
159 uint8_t* dest_ptr = dest;
161 uint64_t chunk_num = (start * unit_size_) / chunk_size_;
162 uint64_t chunk_offs = (start * unit_size_) % chunk_size_;
165 const uint8_t* chunk = data_chunks_[chunk_num];
167 uint64_t copy_size = std::min(count * unit_size_,
168 chunk_size_ - chunk_offs);
170 memcpy(dest_ptr, chunk + chunk_offs, copy_size);
172 dest_ptr += copy_size;
173 count -= (copy_size / unit_size_);
182 SegmentRawDataIterator* Segment::begin_raw_sample_iteration(uint64_t start) const
184 SegmentRawDataIterator* it = new SegmentRawDataIterator;
186 assert(start < sample_count_);
188 it->sample_index = start;
189 it->chunk_num = (start * unit_size_) / chunk_size_;
190 it->chunk_offs = (start * unit_size_) % chunk_size_;
191 it->chunk = data_chunks_[it->chunk_num];
192 it->value = it->chunk + it->chunk_offs;
197 void Segment::continue_raw_sample_iteration(SegmentRawDataIterator* it, uint64_t increase) const
199 lock_guard<recursive_mutex> lock(mutex_);
201 if (it->sample_index > sample_count_)
203 // Fail gracefully if we are asked to deliver data we don't have
206 it->sample_index += increase;
207 it->chunk_offs += (increase * unit_size_);
210 if (it->chunk_offs > (chunk_size_ - 1)) {
212 it->chunk_offs -= chunk_size_;
213 it->chunk = data_chunks_[it->chunk_num];
216 it->value = it->chunk + it->chunk_offs;
219 void Segment::end_raw_sample_iteration(SegmentRawDataIterator* it) const