X-Git-Url: https://sigrok.org/gitweb/?p=pulseview.git;a=blobdiff_plain;f=pv%2Fdata%2Fsegment.cpp;h=88015c3639860597accf8bf23eb21ed98d499e53;hp=111b62b71aadf0c43189540050c55e92de29dc43;hb=c063290ac7189bdd15221450f598504f43286b43;hpb=f3d66e52ed6b454ea7a0662d5e6367e230116a2b diff --git a/pv/data/segment.cpp b/pv/data/segment.cpp index 111b62b7..88015c36 100644 --- a/pv/data/segment.cpp +++ b/pv/data/segment.cpp @@ -1,6 +1,7 @@ /* * This file is part of the PulseView project. * + * Copyright (C) 2017 Soeren Apel * Copyright (C) 2012 Joel Holdsworth * * This program is free software; you can redistribute it and/or modify @@ -14,36 +15,52 @@ * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + * along with this program; if not, see . */ #include "segment.hpp" -#include -#include -#include +#include +#include +#include using std::lock_guard; +using std::min; using std::recursive_mutex; namespace pv { namespace data { +const uint64_t Segment::MaxChunkSize = 10*1024*1024; /* 10MiB */ + Segment::Segment(uint64_t samplerate, unsigned int unit_size) : sample_count_(0), start_time_(0), samplerate_(samplerate), - capacity_(0), - unit_size_(unit_size) + unit_size_(unit_size), + iterator_count_(0), + mem_optimization_requested_(false) { lock_guard lock(mutex_); assert(unit_size_ > 0); + + // Determine the number of samples we can fit in one chunk + // without exceeding MaxChunkSize + chunk_size_ = min(MaxChunkSize, (MaxChunkSize / unit_size_) * unit_size_); + + // Create the initial chunk + current_chunk_ = new uint8_t[chunk_size_]; + data_chunks_.push_back(current_chunk_); + used_samples_ = 0; + unused_samples_ = chunk_size_ / unit_size_; } Segment::~Segment() { lock_guard lock(mutex_); + + for (uint8_t* chunk : data_chunks_) + delete[] chunk; } uint64_t Segment::get_sample_count() const @@ -52,7 +69,7 @@ uint64_t Segment::get_sample_count() const return sample_count_; } -double Segment::start_time() const +const pv::util::Timestamp& Segment::start_time() const { return start_time_; } @@ -72,39 +89,165 @@ unsigned int Segment::unit_size() const return unit_size_; } -void Segment::set_capacity(const uint64_t new_capacity) +void Segment::free_unused_memory() { lock_guard lock(mutex_); - assert(capacity_ >= sample_count_); - if (new_capacity > capacity_) { - capacity_ = new_capacity; - data_.resize((new_capacity * unit_size_) + sizeof(uint64_t)); + // Do not mess with the data chunks if we have iterators pointing at them + if (iterator_count_ > 0) { + mem_optimization_requested_ = true; + return; } + + // No more data will come in, so re-create the last chunk accordingly + uint8_t* resized_chunk = new uint8_t[used_samples_ * unit_size_]; + memcpy(resized_chunk, current_chunk_, used_samples_ * unit_size_); + + delete[] current_chunk_; + current_chunk_ = resized_chunk; + + data_chunks_.pop_back(); + data_chunks_.push_back(resized_chunk); } -uint64_t Segment::capacity() const +void Segment::append_single_sample(void *data) { lock_guard lock(mutex_); - return data_.size(); + + // There will always be space for at least one sample in + // the current chunk, so we do not need to test for space + + memcpy(current_chunk_ + (used_samples_ * unit_size_), data, unit_size_); + used_samples_++; + unused_samples_--; + + if (unused_samples_ == 0) { + current_chunk_ = new uint8_t[chunk_size_]; + data_chunks_.push_back(current_chunk_); + used_samples_ = 0; + unused_samples_ = chunk_size_ / unit_size_; + } + + sample_count_++; } -void Segment::append_data(void *data, uint64_t samples) +void Segment::append_samples(void* data, uint64_t samples) { lock_guard lock(mutex_); - assert(capacity_ >= sample_count_); + if (unused_samples_ >= samples) { + // All samples fit into the current chunk + memcpy(current_chunk_ + (used_samples_ * unit_size_), + data, (samples * unit_size_)); + used_samples_ += samples; + unused_samples_ -= samples; + } else { + // Only a part of the samples fit, split data up between chunks + memcpy(current_chunk_ + (used_samples_ * unit_size_), + data, (unused_samples_ * unit_size_)); + const uint64_t remaining_samples = samples - unused_samples_; + + // If we're out of memory, this will throw std::bad_alloc + current_chunk_ = new uint8_t[chunk_size_]; + data_chunks_.push_back(current_chunk_); + memcpy(current_chunk_, (uint8_t*)data + (unused_samples_ * unit_size_), + (remaining_samples * unit_size_)); + + used_samples_ = remaining_samples; + unused_samples_ = (chunk_size_ / unit_size_) - remaining_samples; + } - // Ensure there's enough capacity to copy. - const uint64_t free_space = capacity_ - sample_count_; - if (free_space < samples) { - set_capacity(sample_count_ + samples); + if (unused_samples_ == 0) { + // If we're out of memory, this will throw std::bad_alloc + current_chunk_ = new uint8_t[chunk_size_]; + data_chunks_.push_back(current_chunk_); + used_samples_ = 0; + unused_samples_ = chunk_size_ / unit_size_; } - memcpy((uint8_t*)data_.data() + sample_count_ * unit_size_, - data, samples * unit_size_); sample_count_ += samples; } +uint8_t* Segment::get_raw_samples(uint64_t start, uint64_t count) const +{ + assert(start < sample_count_); + assert(start + count <= sample_count_); + assert(count > 0); + + lock_guard lock(mutex_); + + uint8_t* dest = new uint8_t[count * unit_size_]; + uint8_t* dest_ptr = dest; + + uint64_t chunk_num = (start * unit_size_) / chunk_size_; + uint64_t chunk_offs = (start * unit_size_) % chunk_size_; + + while (count > 0) { + const uint8_t* chunk = data_chunks_[chunk_num]; + + uint64_t copy_size = min(count * unit_size_, + chunk_size_ - chunk_offs); + + memcpy(dest_ptr, chunk + chunk_offs, copy_size); + + dest_ptr += copy_size; + count -= (copy_size / unit_size_); + + chunk_num++; + chunk_offs = 0; + } + + return dest; +} + +SegmentRawDataIterator* Segment::begin_raw_sample_iteration(uint64_t start) +{ + SegmentRawDataIterator* it = new SegmentRawDataIterator; + + assert(start < sample_count_); + + iterator_count_++; + + it->sample_index = start; + it->chunk_num = (start * unit_size_) / chunk_size_; + it->chunk_offs = (start * unit_size_) % chunk_size_; + it->chunk = data_chunks_[it->chunk_num]; + it->value = it->chunk + it->chunk_offs; + + return it; +} + +void Segment::continue_raw_sample_iteration(SegmentRawDataIterator* it, uint64_t increase) +{ + lock_guard lock(mutex_); + + // Fail gracefully if we are asked to deliver data we don't have + if (it->sample_index > sample_count_) + return; + + it->sample_index += increase; + it->chunk_offs += (increase * unit_size_); + + if (it->chunk_offs > (chunk_size_ - 1)) { + it->chunk_num++; + it->chunk_offs -= chunk_size_; + it->chunk = data_chunks_[it->chunk_num]; + } + + it->value = it->chunk + it->chunk_offs; +} + +void Segment::end_raw_sample_iteration(SegmentRawDataIterator* it) +{ + delete it; + + iterator_count_--; + + if ((iterator_count_ == 0) && mem_optimization_requested_) { + mem_optimization_requested_ = false; + free_unused_memory(); + } +} + } // namespace data } // namespace pv