ACE学习（八）Reactor模式

这个模式为同步读+多线程处理的一个模型，在Windows下面默认的实现是ACE_WFMO_Reactor，他内部使用WaitForMuiltiObject来等待OVERLAPPED当中的event句柄，LINUX下使用ACE_Select_Reacotr实现，内部使用select函数来分配操作。

http://dl.vmall.com/c0bda5pwb4

Demo1

#include "ace/Auto_Ptr.h"
#include "ace/Log_Msg.h"
#include "ace/INET_Addr.h"
#include "ace/SOCK_Acceptor.h"
#include "ace/Reactor.h"
#include "ace/Message_Block.h"
#include "ace/Message_Queue.h"
#include "ace/SOCK_Stream.h"
#include "ace/Synch_Traits.h"
#include "ace/Synch.h"
#include "ace/OS_NS_sys_time.h"
#include "ace/os_include/os_netdb.h"


class ClientAcceptor : public ACE_Event_Handler
{
public:
	virtual ~ClientAcceptor();

	int open(const ACE_INET_Addr &listenAddr);

	// Get this handler's I/O handle.
	virtual ACE_HANDLE get_handle(void) const
	{
		return this->m_acceptor.get_handle();
	}

	// Called when a connection is ready to accept.
	virtual int handle_input(ACE_HANDLE fd = ACE_INVALID_HANDLE);

	// Called when this handler is removed from the ACE_Reactor.
	virtual int handle_close(ACE_HANDLE handle, ACE_Reactor_Mask closeMask);
protected:
	ACE_SOCK_Acceptor m_acceptor;
};

class ClientService : public ACE_Event_Handler
{
public:
	int open(void);
	ACE_SOCK_Stream &peer(void)
	{
		return this->m_sock;
	}

	// Get this handler's I/O handle.
	virtual ACE_HANDLE get_handle(void) const
	{
		return this->m_sock.get_handle();
	}

	// Called when input is available from the client
	virtual int handle_input(ACE_HANDLE fd = ACE_INVALID_HANDLE);

	// Called when output is possible.
	virtual int handle_output(ACE_HANDLE fd = ACE_INVALID_HANDLE);

	// Called when this handler is removed from the ACE_Reactor.
	virtual int handle_close(ACE_HANDLE handle, ACE_Reactor_Mask close_mask);

protected:
	ACE_SOCK_Stream m_sock;
	ACE_Message_Queue<ACE_NULL_SYNCH> m_output_queue;


};


int ClientAcceptor::open(const ACE_INET_Addr &listenAddr)
{
	if (this->m_acceptor.open(listenAddr, 1) == -1)
	{
		ACE_ERROR_RETURN((LM_ERROR, ACE_TEXT("%p\n"), ACE_TEXT("acceptor.open")), -1);
	}
	/**
   * Register handler for I/O events.
   *
   * A handler can be associated with multiple handles. A handle
   * cannot be associated with multiple handlers.
   *
   * The handle will come from ACE_Event_Handler::get_handle().
   *
   * Reactor will call ACE_Event_Handler::add_reference() for a new
   * handler/handle pair.
   *
   * If this handler/handle pair has already been registered, any new
   * masks specified will be added. In this case,
   * ACE_Event_Handler::add_reference() will not be called.
   *
   * If the registered handler is currently suspended, it will remain
   * suspended.  When the handler is resumed, it will have the
   * existing masks plus any masks added through this call. Handlers
   * do not have partial suspensions.
   */

	// Get the event demultiplexors.
    // virtual ACE_Reactor *reactor (void) const;
	
	return this->reactor()->register_handler(this, ACE_Event_Handler::ACCEPT_MASK);
}

int ClientAcceptor::handle_input(ACE_HANDLE)
{
	// 为每次连接都使用单独的服务器处理器对象
	ClientService *client;
	ACE_NEW_RETURN (client, ClientService, -1);
	auto_ptr<ClientService> p(client);

	// client的peer方法返回的是一个ACE_SOCK_Stream对象
	if (this->m_acceptor.accept(client->peer()) == -1)
	{
		ACE_ERROR_RETURN((LM_ERROR, 
			ACE_TEXT("(%P|%t) %p\n"), 
			ACE_TEXT("Failed to accept"), 
			ACE_TEXT("client connection")),
			-1);
	}

	p.release();
	client->reactor(this->reactor());

	// open方法会向反应器登记新得ClientService实例
	if (client->open() == -1)
	{
		client->handle_close(ACE_INVALID_HANDLE, 0);
	}
	return 0;
}

int ClientAcceptor::handle_close(ACE_HANDLE handle, ACE_Reactor_Mask closeMask)
{
	if (this->m_acceptor.get_handle() != ACE_INVALID_HANDLE)
	{
		ACE_Reactor_Mask m = ACE_Event_Handler::ACCEPT_MASK | ACE_Event_Handler::DONT_CALL;
		this->reactor()->remove_handler(this , m);
		this->m_acceptor.close();
	}
	return 0;
}

ClientAcceptor::~ClientAcceptor()
{
	this->handle_close(ACE_INVALID_HANDLE, 0);
}

//--------------------------------------------------
int ClientService::open(void)
{
	ACE_TCHAR peer_name[128];
	ACE_INET_Addr peer_addr;
	if (this->m_sock.get_remote_addr(peer_addr) == 0 &&
		peer_addr.addr_to_string(peer_name, 128) == 0)
	{
		ACE_DEBUG((LM_DEBUG, 
			ACE_TEXT("(%P|%t) Connection from %s\n"),
			peer_name));
	}

	return this->reactor()->register_handler(this, ACE_Event_Handler::READ_MASK);
}

int ClientService::handle_input(ACE_HANDLE)
{
	const size_t INPUT_SIZE = 4096;
	char buffer[INPUT_SIZE];
	ssize_t recv_cnt, send_cnt;

	if (recv_cnt = (this->m_sock.recv(buffer, sizeof(buffer))) <= 0)
	{
		ACE_DEBUG((LM_DEBUG, ACE_TEXT("(%P|%t) Conection closed\n")));
		return -1;
	}

	send_cnt = this->m_sock.send(buffer, ACE_static_cast(size_t, recv_cnt));
	if (send_cnt == recv_cnt)
	{
		return 0;
	}

	// EWOULBLOCK无法现在发送数据
	if (send_cnt == -1 && ACE_OS::last_error() != EWOULDBLOCK)
	{
		ACE_ERROR_RETURN((LM_ERROR, ACE_TEXT("(%P|%t) %p\n"), ACE_TEXT("send")), 0);
	}

	if (send_cnt == -1)
	{
		send_cnt = 0;
	}

	ACE_Message_Block *mb;
	size_t remaining = ACE_static_cast(size_t, (recv_cnt - send_cnt));
	ACE_NEW_RETURN(mb, ACE_Message_Block(&buffer[send_cnt], remaining), -1);
	int output_off = this->m_output_queue.is_empty();
	ACE_Time_Value nowait(ACE_OS::gettimeofday());
	if (this->m_output_queue.enqueue_tail(mb, &nowait) == -1)
	{
		ACE_ERROR((LM_ERROR, ACE_TEXT("(%P|%t) %p; discarding data\n"), ACE_TEXT("enqueue failed")));
		mb->release();
		return 0;
	}

	if (output_off)
	{
		return this->reactor()->register_handler(this, ACE_Event_Handler::WRITE_MASK);
	}
	return 0;
}

int ClientService::handle_output(ACE_HANDLE)
{
	ACE_Message_Block *mb;
	ACE_Time_Value nowait(ACE_OS::gettimeofday());
	while (0 == this->m_output_queue.dequeue_head(mb, &nowait))
	{
		ssize_t send_cnt = this->m_sock.send(mb->rd_ptr(), mb->length());
		if (send_cnt == -1)
		{
			ACE_ERROR((LM_ERROR, ACE_TEXT("(%P|%t) %p\n"), ACE_TEXT("send")));
		}
		else
		{
			mb->rd_ptr(ACE_static_cast(size_t, send_cnt));
		}
		if(mb->length() > 0)
		{
			this->m_output_queue.enqueue_head(mb);
			break;
		}
		mb->release();

	}
	return (this->m_output_queue.is_empty()) ? -1:0;
}

int ClientService::handle_close(ACE_HANDLE, ACE_Reactor_Mask mask)
{
	if(mask == ACE_Event_Handler::WRITE_MASK)
		return 0;
	mask = ACE_Event_Handler::ALL_EVENTS_MASK |
		ACE_Event_Handler::DONT_CALL;
	this->reactor()->remove_handler(this, mask);
	this->m_sock.close();
	this->m_output_queue.flush();
	delete this;
	return 0;
}

int ACE_TMAIN(int, ACE_TCHAR *[])
{
	ACE_INET_Addr port_to_listen("5000");
	ClientAcceptor acceptor;

	// ACE_Event_Handler含有一个ACE_Reactor指针，用于方便的引用正在使用的反应器
	// 该反应器实例会在第一次用到的时候创建，在程序结束自动关闭，单例模式+智能指针？

	// Set the event demultiplexors.
    // virtual void reactor (ACE_Reactor *reactor);
	acceptor.reactor(ACE_Reactor::instance());

	if (acceptor.open(port_to_listen) == -1)
	{
		return 1;
	}

	ACE_Reactor::instance()->run_reactor_event_loop();
	return 0;
}

Demo2

// $Id: HAStatus.cpp 91626 2010-09-07 10:59:20Z johnnyw $

#include "ace/OS_NS_sys_time.h"
#include "ace/os_include/os_netdb.h"

// Listing 1 code/ch07
#include "ace/Auto_Ptr.h"
#include "ace/Log_Msg.h"
#include "ace/INET_Addr.h"
#include "ace/SOCK_Acceptor.h"
#include "ace/Reactor.h"

class ClientAcceptor : public ACE_Event_Handler
{
public:
  virtual ~ClientAcceptor ();

  //FUZZ: disable check_for_lack_ACE_OS
  int open (const ACE_INET_Addr &listen_addr);
  //FUZZ: enable check_for_lack_ACE_OS

  // Get this handler's I/O handle.
  virtual ACE_HANDLE get_handle (void) const
    { return this->acceptor_.get_handle (); }

  // Called when a connection is ready to accept.
  virtual int handle_input (ACE_HANDLE fd = ACE_INVALID_HANDLE);

  // Called when this handler is removed from the ACE_Reactor.
  virtual int handle_close (ACE_HANDLE handle,
                            ACE_Reactor_Mask close_mask);

protected:
  ACE_SOCK_Acceptor acceptor_;
};
// Listing 1

// Listing 6 code/ch07
#include "ace/Message_Block.h"
#include "ace/Message_Queue.h"
#include "ace/SOCK_Stream.h"
#include "ace/Synch.h"

class ClientService : public ACE_Event_Handler
{
public:
  ACE_SOCK_Stream &peer (void) { return this->sock_; }

  //FUZZ: disable check_for_lack_ACE_OS
  int open (void);
  //FUZZ: enable check_for_lack_ACE_OS

  // Get this handler's I/O handle.
  virtual ACE_HANDLE get_handle (void) const
    { return this->sock_.get_handle (); }

  // Called when input is available from the client.
  virtual int handle_input (ACE_HANDLE fd = ACE_INVALID_HANDLE);

  // Called when output is possible.
  virtual int handle_output (ACE_HANDLE fd = ACE_INVALID_HANDLE);

  // Called when this handler is removed from the ACE_Reactor.
  virtual int handle_close (ACE_HANDLE handle,
                            ACE_Reactor_Mask close_mask);

protected:
  ACE_SOCK_Stream sock_;
  ACE_Message_Queue<ACE_NULL_SYNCH> output_queue_;
};
// Listing 6

// Listing 5 code/ch07
ClientAcceptor::~ClientAcceptor ()
{
  this->handle_close (ACE_INVALID_HANDLE, 0);
}
// Listing 5

// Listing 2 code/ch07
int
ClientAcceptor::open (const ACE_INET_Addr &listen_addr)
{
  if (this->acceptor_.open (listen_addr, 1) == -1)
    ACE_ERROR_RETURN ((LM_ERROR,
                       ACE_TEXT ("%p\n"),
                       ACE_TEXT ("acceptor.open")),
                      -1);
  return this->reactor ()->register_handler
    (this, ACE_Event_Handler::ACCEPT_MASK);
}
// Listing 2

// Listing 3 code/ch07
int
ClientAcceptor::handle_input (ACE_HANDLE)
{
  ClientService *client;
  ACE_NEW_RETURN (client, ClientService, -1);
  auto_ptr<ClientService> p (client);

  if (this->acceptor_.accept (client->peer ()) == -1)
    ACE_ERROR_RETURN ((LM_ERROR,
                       ACE_TEXT ("(%P|%t) %p\n"),
                       ACE_TEXT ("Failed to accept ")
                       ACE_TEXT ("client connection")),
                      -1);
  p.release ();
  client->reactor (this->reactor ());
  if (client->open () == -1)
    client->handle_close (ACE_INVALID_HANDLE, 0);
  return 0;
}
// Listing 3

// Listing 4 code/ch07
int
ClientAcceptor::handle_close (ACE_HANDLE, ACE_Reactor_Mask)
{
  if (this->acceptor_.get_handle () != ACE_INVALID_HANDLE)
    {
      ACE_Reactor_Mask m = ACE_Event_Handler::ACCEPT_MASK |
                           ACE_Event_Handler::DONT_CALL;
      this->reactor ()->remove_handler (this, m);
      this->acceptor_.close ();
    }
  return 0;
}
// Listing 4

// Listing 7 code/ch07
int
ClientService::open (void)
{
  ACE_TCHAR peer_name[MAXHOSTNAMELEN];
  ACE_INET_Addr peer_addr;
  if (this->sock_.get_remote_addr (peer_addr) == 0 &&
      peer_addr.addr_to_string (peer_name, MAXHOSTNAMELEN) == 0)
    ACE_DEBUG ((LM_DEBUG,
                ACE_TEXT ("(%P|%t) Connection from %s\n"),
                peer_name));
  return this->reactor ()->register_handler
    (this, ACE_Event_Handler::READ_MASK);
}
// Listing 7

// Listing 8 code/ch07
int
ClientService::handle_input (ACE_HANDLE)
{
  const size_t INPUT_SIZE = 4096;
  char buffer[INPUT_SIZE];
  ssize_t recv_cnt, send_cnt;

  if ((recv_cnt = this->sock_.recv (buffer, sizeof(buffer))) <= 0)
    {
      ACE_DEBUG ((LM_DEBUG,
                  ACE_TEXT ("(%P|%t) Connection closed\n")));
      return -1;
    }

  send_cnt =
    this->sock_.send (buffer, static_cast<size_t> (recv_cnt));
  if (send_cnt == recv_cnt)
    return 0;
  if (send_cnt == -1 && ACE_OS::last_error () != EWOULDBLOCK)
    ACE_ERROR_RETURN ((LM_ERROR,
                       ACE_TEXT ("(%P|%t) %p\n"),
                       ACE_TEXT ("send")),
                      0);
  if (send_cnt == -1)
    send_cnt = 0;
  ACE_Message_Block *mb = 0;
  size_t remaining =
    static_cast<size_t> ((recv_cnt - send_cnt));
  ACE_NEW_RETURN (mb, ACE_Message_Block (remaining), -1);
  mb->copy (&buffer[send_cnt], remaining);
  int output_off = this->output_queue_.is_empty ();
  ACE_Time_Value nowait (ACE_OS::gettimeofday ());
  if (this->output_queue_.enqueue_tail (mb, &nowait) == -1)
    {
      ACE_ERROR ((LM_ERROR,
                  ACE_TEXT ("(%P|%t) %p; discarding data\n"),
                  ACE_TEXT ("enqueue failed")));
      mb->release ();
      return 0;
    }
  if (output_off)
    return this->reactor ()->register_handler
      (this, ACE_Event_Handler::WRITE_MASK);
  return 0;
}
// Listing 8

// Listing 9 code/ch07
int
ClientService::handle_output (ACE_HANDLE)
{
  ACE_Message_Block *mb = 0;
  ACE_Time_Value nowait (ACE_OS::gettimeofday ());
  while (0 <= this->output_queue_.dequeue_head
                                    (mb, &nowait))
    {
      ssize_t send_cnt =
        this->sock_.send (mb->rd_ptr (), mb->length ());
      if (send_cnt == -1)
        ACE_ERROR ((LM_ERROR,
                    ACE_TEXT ("(%P|%t) %p\n"),
                    ACE_TEXT ("send")));
      else
        mb->rd_ptr (static_cast<size_t> (send_cnt));
      if (mb->length () > 0)
        {
          this->output_queue_.enqueue_head (mb);
          break;
        }
      mb->release ();
    }
  return (this->output_queue_.is_empty ()) ? -1 : 0;
}
// Listing 9

// Listing 10 code/ch07
int
ClientService::handle_close (ACE_HANDLE, ACE_Reactor_Mask mask)
{
  if (mask == ACE_Event_Handler::WRITE_MASK)
    return 0;
  mask = ACE_Event_Handler::ALL_EVENTS_MASK |
         ACE_Event_Handler::DONT_CALL;
  this->reactor ()->remove_handler (this, mask);
  this->sock_.close ();
  this->output_queue_.flush ();
  delete this;
  return 0;
}
// Listing 10

// Listing 12 code/ch07
class LoopStopper : public ACE_Event_Handler
{
public:
  LoopStopper (int signum = SIGINT);

  // Called when object is signaled by OS.
  virtual int handle_signal (int signum,
                             siginfo_t * = 0,
                             ucontext_t * = 0);
};

LoopStopper::LoopStopper (int signum)
{
  ACE_Reactor::instance ()->register_handler (signum, this);
}

int
LoopStopper::handle_signal (int, siginfo_t *, ucontext_t *)
{
  ACE_Reactor::instance ()->end_reactor_event_loop ();
  return 0;
}
// Listing 12

// Listing 13 code/ch07
#include "ace/Signal.h"

class LogSwitcher : public ACE_Event_Handler
{
public:
  LogSwitcher (int on_sig, int off_sig);

  // Called when object is signaled by OS.
  virtual int handle_signal (int signum,
                             siginfo_t * = 0,
                             ucontext_t * = 0);

  // Called when an exceptional event occurs.
  virtual int handle_exception (ACE_HANDLE fd = ACE_INVALID_HANDLE);

private:
  LogSwitcher () {}

  int on_sig_;       // Signal to turn logging on
  int off_sig_;      // Signal to turn logging off
  int on_off_;       // 1 == turn on, 0 == turn off
};

LogSwitcher::LogSwitcher (int on_sig, int off_sig)
  : on_sig_ (on_sig), off_sig_ (off_sig)
{
  ACE_Sig_Set sigs;
  sigs.sig_add (on_sig);
  sigs.sig_add (off_sig);
  ACE_Reactor::instance ()->register_handler (sigs, this);
}
// Listing 13

// Listing 14 code/ch07
int
LogSwitcher::handle_signal (int signum, siginfo_t *, ucontext_t *)
{
  if (signum == this->on_sig_ || signum == this->off_sig_)
    {
      this->on_off_ = signum == this->on_sig_;
      ACE_Reactor::instance ()->notify (this);
    }
  return 0;
}
// Listing 14

// Listing 15 code/ch07
int
LogSwitcher::handle_exception (ACE_HANDLE)
{
  if (this->on_off_)
    ACE_LOG_MSG->clr_flags (ACE_Log_Msg::SILENT);
  else
    ACE_LOG_MSG->set_flags (ACE_Log_Msg::SILENT);
  return 0;
}
// Listing 15

// Listing 11 code/ch07
int ACE_TMAIN (int, ACE_TCHAR *[])
{
  ACE_INET_Addr port_to_listen ("HAStatus");
  ClientAcceptor acceptor;
  acceptor.reactor (ACE_Reactor::instance ());
  if (acceptor.open (port_to_listen) == -1)
    return 1;

  ACE_Reactor::instance ()->run_reactor_event_loop ();

  return (0);
}
// Listing 11

 

http://wenku.baidu.com/view/866966a1284ac850ad0242ab.html
http://daimojingdeyu.iteye.com/blog/828696
http://book.2cto.com/201208/1893.html
http://blog.csdn.net/sparkliang/article/details/4957744
http://developer.51cto.com/art/201208/354591.htm

acceptor-connector

http://shanghai.kankanews.com/mobile/2013-05-20/1546541.shtml
http://auto.people.com.cn/n/2013/0317/c1005-20815213.html
http://scitech.people.com.cn/n/2013/0310/c1007-20736417.html