File size: 4,367 Bytes
1ce325b |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 |
#include "chain.hh"
#include "io.hh"
#include "../exception.hh"
#include "../pcqueue.hh"
#include <cstdlib>
#include <new>
#include <iostream>
#include <stdint.h>
namespace util {
namespace stream {
ChainConfigException::ChainConfigException() throw() { *this << "Chain configured with "; }
ChainConfigException::~ChainConfigException() throw() {}
Thread::~Thread() {
thread_.join();
}
void Thread::UnhandledException(const std::exception &e) {
std::cerr << e.what() << std::endl;
abort();
}
void Recycler::Run(const ChainPosition &position) {
for (Link l(position); l; ++l) {
l->SetValidSize(position.GetChain().BlockSize());
}
}
const Recycler kRecycle = Recycler();
Chain::Chain(const ChainConfig &config) : config_(config), complete_called_(false) {
UTIL_THROW_IF(!config.entry_size, ChainConfigException, "zero-size entries.");
UTIL_THROW_IF(!config.block_count, ChainConfigException, "block count zero");
UTIL_THROW_IF(config.total_memory < config.entry_size * config.block_count, ChainConfigException, config.total_memory << " total memory, too small for " << config.block_count << " blocks of containing entries of size " << config.entry_size);
// Round down block size to a multiple of entry size.
block_size_ = config.total_memory / (config.block_count * config.entry_size) * config.entry_size;
}
Chain::~Chain() {
Wait();
}
ChainPosition Chain::Add() {
if (!Running()) Start();
PCQueue<Block> &in = queues_.back();
queues_.push_back(new PCQueue<Block>(config_.block_count));
return ChainPosition(in, queues_.back(), this, progress_);
}
Chain &Chain::operator>>(const WriteAndRecycle &writer) {
threads_.push_back(new Thread(Complete(), writer));
return *this;
}
void Chain::Wait(bool release_memory) {
if (queues_.empty()) {
assert(threads_.empty());
return; // Nothing to wait for.
}
if (!complete_called_) CompleteLoop();
threads_.clear();
for (std::size_t i = 0; queues_.front().Consume(); ++i) {
if (i == config_.block_count) {
std::cerr << "Chain ending without poison." << std::endl;
abort();
}
}
queues_.clear();
progress_.Finished();
complete_called_ = false;
if (release_memory) memory_.reset();
}
void Chain::Start() {
Wait(false);
if (!memory_.get()) {
// Allocate memory.
assert(threads_.empty());
assert(queues_.empty());
std::size_t malloc_size = block_size_ * config_.block_count;
memory_.reset(MallocOrThrow(malloc_size));
}
// This queue can accomodate all blocks.
queues_.push_back(new PCQueue<Block>(config_.block_count));
// Populate the lead queue with blocks.
uint8_t *base = static_cast<uint8_t*>(memory_.get());
for (std::size_t i = 0; i < config_.block_count; ++i) {
queues_.front().Produce(Block(base, block_size_));
base += block_size_;
}
}
ChainPosition Chain::Complete() {
assert(Running());
UTIL_THROW_IF(complete_called_, util::Exception, "CompleteLoop() called twice");
complete_called_ = true;
return ChainPosition(queues_.back(), queues_.front(), this, progress_);
}
Link::Link() : in_(NULL), out_(NULL), poisoned_(true) {}
void Link::Init(const ChainPosition &position) {
UTIL_THROW_IF(in_, util::Exception, "Link::Init twice");
in_ = position.in_;
out_ = position.out_;
poisoned_ = false;
progress_ = position.progress_;
in_->Consume(current_);
}
Link::Link(const ChainPosition &position) : in_(NULL) {
Init(position);
}
Link::~Link() {
if (current_) {
// Probably an exception unwinding.
std::cerr << "Last input should have been poison. The program should end soon with an error. If it doesn't, there's a bug." << std::endl;
// abort();
} else {
if (!poisoned_) {
// Poison is a block whose memory pointer is NULL.
//
// Because we're in the else block,
// we know that the memory pointer of current_ is NULL.
//
// Pass the current (poison) block!
out_->Produce(current_);
}
}
}
Link &Link::operator++() {
assert(current_);
progress_ += current_.ValidSize();
out_->Produce(current_);
in_->Consume(current_);
if (!current_) {
poisoned_ = true;
out_->Produce(current_);
}
return *this;
}
void Link::Poison() {
assert(!poisoned_);
current_.SetToPoison();
out_->Produce(current_);
poisoned_ = true;
}
} // namespace stream
} // namespace util
|