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1 | /* | |
2 | * This file is part of the PulseView project. | |
3 | * | |
4 | * Copyright (C) 2017 Soeren Apel <soeren@apelpie.net> | |
5 | * Copyright (C) 2012 Joel Holdsworth <joel@airwebreathe.org.uk> | |
6 | * | |
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. | |
11 | * | |
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. | |
16 | * | |
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/>. | |
19 | */ | |
20 | ||
21 | #include "segment.hpp" | |
22 | ||
23 | #include <cassert> | |
24 | #include <cstdlib> | |
25 | #include <cstring> | |
26 | ||
27 | using std::lock_guard; | |
28 | using std::min; | |
29 | using std::recursive_mutex; | |
30 | ||
31 | namespace pv { | |
32 | namespace data { | |
33 | ||
34 | const uint64_t Segment::MaxChunkSize = 10 * 1024 * 1024; /* 10MiB */ | |
35 | ||
36 | Segment::Segment(uint64_t samplerate, unsigned int unit_size) : | |
37 | sample_count_(0), | |
38 | start_time_(0), | |
39 | samplerate_(samplerate), | |
40 | unit_size_(unit_size), | |
41 | iterator_count_(0), | |
42 | mem_optimization_requested_(false), | |
43 | is_complete_(false) | |
44 | { | |
45 | lock_guard<recursive_mutex> lock(mutex_); | |
46 | assert(unit_size_ > 0); | |
47 | ||
48 | // Determine the number of samples we can fit in one chunk | |
49 | // without exceeding MaxChunkSize | |
50 | chunk_size_ = min(MaxChunkSize, (MaxChunkSize / unit_size_) * unit_size_); | |
51 | ||
52 | // Create the initial chunk | |
53 | current_chunk_ = new uint8_t[chunk_size_]; | |
54 | data_chunks_.push_back(current_chunk_); | |
55 | used_samples_ = 0; | |
56 | unused_samples_ = chunk_size_ / unit_size_; | |
57 | } | |
58 | ||
59 | Segment::~Segment() | |
60 | { | |
61 | lock_guard<recursive_mutex> lock(mutex_); | |
62 | ||
63 | for (uint8_t* chunk : data_chunks_) | |
64 | delete[] chunk; | |
65 | } | |
66 | ||
67 | uint64_t Segment::get_sample_count() const | |
68 | { | |
69 | lock_guard<recursive_mutex> lock(mutex_); | |
70 | return sample_count_; | |
71 | } | |
72 | ||
73 | const pv::util::Timestamp& Segment::start_time() const | |
74 | { | |
75 | return start_time_; | |
76 | } | |
77 | ||
78 | double Segment::samplerate() const | |
79 | { | |
80 | return samplerate_; | |
81 | } | |
82 | ||
83 | void Segment::set_samplerate(double samplerate) | |
84 | { | |
85 | samplerate_ = samplerate; | |
86 | } | |
87 | ||
88 | unsigned int Segment::unit_size() const | |
89 | { | |
90 | return unit_size_; | |
91 | } | |
92 | ||
93 | void Segment::set_complete() | |
94 | { | |
95 | is_complete_ = true; | |
96 | } | |
97 | ||
98 | bool Segment::is_complete() const | |
99 | { | |
100 | return is_complete_; | |
101 | } | |
102 | ||
103 | void Segment::free_unused_memory() | |
104 | { | |
105 | lock_guard<recursive_mutex> lock(mutex_); | |
106 | ||
107 | // Do not mess with the data chunks if we have iterators pointing at them | |
108 | if (iterator_count_ > 0) { | |
109 | mem_optimization_requested_ = true; | |
110 | return; | |
111 | } | |
112 | ||
113 | // No more data will come in, so re-create the last chunk accordingly | |
114 | uint8_t* resized_chunk = new uint8_t[used_samples_ * unit_size_]; | |
115 | memcpy(resized_chunk, current_chunk_, used_samples_ * unit_size_); | |
116 | ||
117 | delete[] current_chunk_; | |
118 | current_chunk_ = resized_chunk; | |
119 | ||
120 | data_chunks_.pop_back(); | |
121 | data_chunks_.push_back(resized_chunk); | |
122 | } | |
123 | ||
124 | void Segment::append_single_sample(void *data) | |
125 | { | |
126 | lock_guard<recursive_mutex> lock(mutex_); | |
127 | ||
128 | // There will always be space for at least one sample in | |
129 | // the current chunk, so we do not need to test for space | |
130 | ||
131 | memcpy(current_chunk_ + (used_samples_ * unit_size_), data, unit_size_); | |
132 | used_samples_++; | |
133 | unused_samples_--; | |
134 | ||
135 | if (unused_samples_ == 0) { | |
136 | current_chunk_ = new uint8_t[chunk_size_]; | |
137 | data_chunks_.push_back(current_chunk_); | |
138 | used_samples_ = 0; | |
139 | unused_samples_ = chunk_size_ / unit_size_; | |
140 | } | |
141 | ||
142 | sample_count_++; | |
143 | } | |
144 | ||
145 | void Segment::append_samples(void* data, uint64_t samples) | |
146 | { | |
147 | lock_guard<recursive_mutex> lock(mutex_); | |
148 | ||
149 | const uint8_t* data_byte_ptr = (uint8_t*)data; | |
150 | uint64_t remaining_samples = samples; | |
151 | uint64_t data_offset = 0; | |
152 | ||
153 | do { | |
154 | uint64_t copy_count = 0; | |
155 | ||
156 | if (remaining_samples <= unused_samples_) { | |
157 | // All samples fit into the current chunk | |
158 | copy_count = remaining_samples; | |
159 | } else { | |
160 | // Only a part of the samples fit, fill up current chunk | |
161 | copy_count = unused_samples_; | |
162 | } | |
163 | ||
164 | const uint8_t* dest = &(current_chunk_[used_samples_ * unit_size_]); | |
165 | const uint8_t* src = &(data_byte_ptr[data_offset]); | |
166 | memcpy((void*)dest, (void*)src, (copy_count * unit_size_)); | |
167 | ||
168 | used_samples_ += copy_count; | |
169 | unused_samples_ -= copy_count; | |
170 | remaining_samples -= copy_count; | |
171 | data_offset += (copy_count * unit_size_); | |
172 | ||
173 | if (unused_samples_ == 0) { | |
174 | // If we're out of memory, this will throw std::bad_alloc | |
175 | current_chunk_ = new uint8_t[chunk_size_]; | |
176 | data_chunks_.push_back(current_chunk_); | |
177 | used_samples_ = 0; | |
178 | unused_samples_ = chunk_size_ / unit_size_; | |
179 | } | |
180 | } while (remaining_samples > 0); | |
181 | ||
182 | sample_count_ += samples; | |
183 | } | |
184 | ||
185 | void Segment::get_raw_samples(uint64_t start, uint64_t count, | |
186 | uint8_t* dest) const | |
187 | { | |
188 | assert(start < sample_count_); | |
189 | assert(start + count <= sample_count_); | |
190 | assert(count > 0); | |
191 | assert(dest != nullptr); | |
192 | ||
193 | lock_guard<recursive_mutex> lock(mutex_); | |
194 | ||
195 | uint8_t* dest_ptr = dest; | |
196 | ||
197 | uint64_t chunk_num = (start * unit_size_) / chunk_size_; | |
198 | uint64_t chunk_offs = (start * unit_size_) % chunk_size_; | |
199 | ||
200 | while (count > 0) { | |
201 | const uint8_t* chunk = data_chunks_[chunk_num]; | |
202 | ||
203 | uint64_t copy_size = min(count * unit_size_, | |
204 | chunk_size_ - chunk_offs); | |
205 | ||
206 | memcpy(dest_ptr, chunk + chunk_offs, copy_size); | |
207 | ||
208 | dest_ptr += copy_size; | |
209 | count -= (copy_size / unit_size_); | |
210 | ||
211 | chunk_num++; | |
212 | chunk_offs = 0; | |
213 | } | |
214 | } | |
215 | ||
216 | SegmentRawDataIterator* Segment::begin_raw_sample_iteration(uint64_t start) | |
217 | { | |
218 | SegmentRawDataIterator* it = new SegmentRawDataIterator; | |
219 | ||
220 | assert(start < sample_count_); | |
221 | ||
222 | iterator_count_++; | |
223 | ||
224 | it->sample_index = start; | |
225 | it->chunk_num = (start * unit_size_) / chunk_size_; | |
226 | it->chunk_offs = (start * unit_size_) % chunk_size_; | |
227 | it->chunk = data_chunks_[it->chunk_num]; | |
228 | it->value = it->chunk + it->chunk_offs; | |
229 | ||
230 | return it; | |
231 | } | |
232 | ||
233 | void Segment::continue_raw_sample_iteration(SegmentRawDataIterator* it, uint64_t increase) | |
234 | { | |
235 | // Fail gracefully if we are asked to deliver data we don't have | |
236 | if (it->sample_index > sample_count_) | |
237 | return; | |
238 | ||
239 | it->sample_index += increase; | |
240 | it->chunk_offs += (increase * unit_size_); | |
241 | ||
242 | if (it->chunk_offs > (chunk_size_ - 1)) { | |
243 | it->chunk_num++; | |
244 | it->chunk_offs -= chunk_size_; | |
245 | it->chunk = data_chunks_[it->chunk_num]; | |
246 | } | |
247 | ||
248 | it->value = it->chunk + it->chunk_offs; | |
249 | } | |
250 | ||
251 | void Segment::end_raw_sample_iteration(SegmentRawDataIterator* it) | |
252 | { | |
253 | delete it; | |
254 | ||
255 | iterator_count_--; | |
256 | ||
257 | if ((iterator_count_ == 0) && mem_optimization_requested_) { | |
258 | mem_optimization_requested_ = false; | |
259 | free_unused_memory(); | |
260 | } | |
261 | } | |
262 | ||
263 | } // namespace data | |
264 | } // namespace pv |