Question

In C++, code a circular linked buffer to be used with a producer/consumer synchronized solution

Answer 1

#include <mutex>
#include <deque>
#include <chrono>
#include <condition_variable>
#include <thread>
#include <iostream>

using std::deque;
std::mutex mux,cout_mux;
std::condition_variable condi;

class MyBuffer
{
public:
void add(int mynum) {
while (true) {
std::unique_lock<std::mutex> locker(mux);
condi.wait(locker, [this](){return buffer_.size() < size_;});
buffer_.push_back(mynum);
locker.unlock();
condi.notify_all();
return;
}
}
int remove() {
while (true)
{
std::unique_lock<std::mutex> locker(mux);
condi.wait(locker, [this](){return buffer_.size() > 0;});
int back = buffer_.back();
buffer_.pop_back();
locker.unlock();
condi.notify_all();
return back;
}
}
MyBuffer() {}
private:
deque<int> buffer_;
const unsigned int size_ = 10;
};

class MyConsumer
{
public:
MyConsumer(MyBuffer* buffer)
{
this->buffer_ = buffer;
}
void run() {
while (true) {
int num = buffer_->remove();
cout_mux.lock();
std::cout << "Consumed : " << num << std::endl;
std::this_thread::sleep_for(std::chrono::milliseconds(50));
cout_mux.unlock();
}
}
private:
MyBuffer *buffer_;
};

class MyProducer
{
public:
MyProducer(MyBuffer* buffer)
{
this->buffer_ = buffer;
}
void run() {
while (true) {
int num = std::rand() % 100;
buffer_->add(num);
cout_mux.lock();
std::cout << "Produced : " << num << std::endl;
std::this_thread::sleep_for(std::chrono::milliseconds(50));
cout_mux.unlock();
}
}
private:
MyBuffer *buffer_;
};

int main() {
MyBuffer buff;
MyProducer pro(&buff);
MyConsumer con(&buff);

std::thread producer_thread(&MyProducer::run, &pro);
std::thread consumer_thread(&MyConsumer::run, &con);

producer_thread.join();
consumer_thread.join();
getchar();
return 0;
}