gearman/util/instance.hpp

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 * 
 *  DataDifferential Utility Library
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#pragma once

#include <arpa/inet.h>
#include <cstdio>
#include <cerrno>
#include <cassert>
#include <cstddef>
#include <sys/socket.h>
#include <string>

#include "util/operation.hpp"

struct addrinfo;

namespace datadifferential {
namespace util {

class Instance
{
private:
  enum connection_state_t {
    NOT_WRITING,
    NEXT_CONNECT_ADDRINFO,
    CONNECT,
    CONNECTING,
    CONNECTED,
    WRITING,
    READING,
    FINISHED
  };
  std::string _last_error;

public: // Callbacks
  class Finish {

  public:
    virtual ~Finish() { }

    virtual bool call(const bool, const std::string &)= 0;
  };


public:
  Instance(const std::string& hostname_arg, const std::string& service_arg);

  Instance(const std::string& hostname_arg, const in_port_t port_arg);

  ~Instance();

  bool run();

  void set_finish(Finish *arg)
  {
    _finish_fn= arg;
  }

  void push(util::Operation *next)
  {
    _operations.push_back(next);
  }

private:
  void close_socket();

  void free_addrinfo();

  bool more_to_read() const;

  std::string _host;
  std::string _service;
  int _sockfd;
  connection_state_t state;
  struct addrinfo *_addrinfo;
  struct addrinfo *_addrinfo_next;
  Finish *_finish_fn;
  Operation::vector _operations;
};

} /* namespace util */
} /* namespace datadifferential */