mogmail – connector module with boost::asio

mogmail - boost::asio を利用したコネクタ

・connector.h

   1: // Copyright (c) 2011 Mog Project. All rights reserved.

   2:  

   3: #ifndef _MOG_NET_CONNECTER_H_

   4: #define _MOG_NET_CONNECTER_H_

   5: #pragma once

   6:  

   7: #include <string>

   8: #include <deque>

   9: #include <boost/scoped_ptr.hpp>

  10: #ifdef _WIN32

  11: #define _WIN32_WINNT 0x0501

  12: #endif  // _WIN32

  13: #include <boost/asio.hpp>

  14:  

  15: namespace mog {

  16: namespace net {

  17:  

  18: // A class manages text-based TCP connection.

  19: class Connecter {

  20:  public:

  21:   // Create connection to server.

  22:   Connecter(std::string const& address, std::string const& port, bool spool = false);

  23:   // Disconnect from server.

  24:   ~Connecter();

  25:   // Write one line.

  26:   void WriteLine(std::string const& line);

  27:   // Read one line.

  28:   void ReadLine(std::string * line);

  29:   // Flush buffered messages.

  30:   void Flush();

  31:   // If there is no response, return true.

  32:   bool IsEmpty() const;

  33:   // Mutator of spool switch.

  34:   void set_spool(bool spool) { spool_ = spool; }

  35:   // Accessor of spool switch.

  36:   bool spool() const { return spool_; }

  37:  

  38:  private:

  39:   static size_t const                             SOCKET_SIZE = 8192;

  40:   boost::asio::io_service                         io_service_;

  41:   boost::scoped_ptr<boost::asio::ip::tcp::socket> socket_;

  42:   std::deque<std::string>                         buffer_;

  43:   bool spool_;

  44:  

  45:   // Send requests.

  46:   void Request(std::string const& request);

  47:   // Recieve response.

  48:   void Response();

  49: };

  50:  

  51: }  // namespace net

  52: }  // namespace mog

  53: #endif  // _MOG_NET_CONNECTER_H_

・connector.cc

   1: // Copyright (c) 2011 Mog Project. All rights reserved.

   2:  

   3: #include "connecter.h"

   4: #include <iostream>

   5: #include <algorithm>

   6:  

   7: namespace mog {

   8: namespace net {

   9:  

  10: ////////////////////////////////////////////////////////////////////////////////

  11: // Connecter

  12: Connecter::Connecter(std::string const& address, std::string const& port, bool spool)

  13:     : spool_(spool), socket_(new boost::asio::ip::tcp::socket(io_service_)) {

  14:   boost::asio::ip::tcp::resolver resolver(io_service_);

  15:   boost::asio::ip::tcp::resolver::query query(address, port);

  16:   boost::asio::ip::tcp::resolver::iterator endpoint_iterator = resolver.resolve(query);

  17:   boost::asio::ip::tcp::resolver::iterator end;

  18:  

  19:   boost::system::error_code error = boost::asio::error::host_not_found;

  20:  

  21:   while (error && endpoint_iterator != end) {

  22:     socket_->close();

  23:     socket_->connect(*endpoint_iterator++, error);

  24:   }

  25:   if (error) {

  26:     throw boost::system::system_error(error);

  27:   }

  28: }

  29:  

  30: Connecter::~Connecter() {

  31:   try {

  32:     socket_->close();

  33:   } catch(...) {}

  34: }

  35:  

  36: void Connecter::WriteLine(std::string const& line) {

  37:   Request(line + '\n');

  38: }

  39:  

  40: void Connecter::ReadLine(std::string * line) {

  41:   if ( buffer_.empty() ) { Response(); }

  42:   *line = buffer_.front();

  43:   buffer_.pop_front();

  44: }

  45:  

  46: void Connecter::Request(std::string const& request) {

  47:   socket_->write_some(boost::asio::buffer(request, request.size()));

  48:   if (spool_) { std::cerr << "[SEND] " << request; }

  49: }

  50:  

  51: void Connecter::Response() {

  52:   boost::array<char, SOCKET_SIZE> buf;

  53:   std::stringstream str;

  54:  

  55:   // Recieve socket.

  56:   for (;;) {

  57:     size_t length = socket_->read_some(boost::asio::buffer(buf));

  58:     str.write(buf.data(), length);

  59:     if (SOCKET_SIZE != length) { break; }

  60:   }

  61:  

  62:   // Convert lines to buffer.

  63:   std::string line;

  64:   while (std::getline(str, line, '\n')) {

  65:     line.erase(std::remove(line.begin(), line.end(), '\r'), line.end());  // Remove carriage return.

  66:     buffer_.push_back(line);

  67:     if (spool_) { std::cerr << "[RECV] " << line << '\n'; }

  68:   }

  69: }

  70:  

  71: void Connecter::Flush() {

  72:   if (socket_->available()) {  // Thrown on faulure, boost::system::system_error.

  73:     Response();

  74:   }

  75:   buffer_.clear();

  76: }

  77:  

  78: bool Connecter::IsEmpty() const {

  79:   if (buffer_.empty() && !socket_->available()) { return true; }

  80:   return false;

  81: }

  82:  

  83: }  // namespace net

  84: }  // namespace mog

参考：Erase-Removeイディオム
http://ja.wikibooks.org/wiki/More_C%2B%2B_Idioms/%E6%B6%88%E5%8E%BB%E3%83%BB%E5%89%8A%E9%99%A4(Erase-Remove)