// file      : ace/RMCast/Socket.cpp
// author    : Boris Kolpackov <boris@kolpackov.net>
// cvs-id    : Socket.cpp,v 1.18 2006/03/01 23:48:42 shuston Exp

#include "ace/OS_Memory.h"
#include "ace/OS_NS_stdio.h"
#include "ace/OS_NS_stdlib.h"
#include "ace/OS_NS_string.h"
#include "ace/OS_NS_unistd.h"
#include "ace/OS_NS_sys_time.h" // gettimeofday

#include "ace/Unbounded_Queue.h"

#include "ace/Pipe.h"

#include "Stack.h"
#include "Protocol.h"
#include "Bits.h"

#include "Fragment.h"
#include "Reassemble.h"
#include "Acknowledge.h"
#include "Retransmit.h"
#include "Flow.h"
#include "Link.h"

#include "Socket.h"

/*
#include <iostream>
using std::cerr;
using std::endl;
*/

namespace ACE_RMCast
{
  class Socket_Impl : protected Element
  {
  public:
    ~Socket_Impl ();

    Socket_Impl (Address const& a, bool loop, Parameters const& params);

  public:
    void
    send_ (void const* buf, size_t s);

    ssize_t
    recv_ (void* buf,
           size_t s,
           ACE_Time_Value const* timeout,
           ACE_INET_Addr* from);

    ssize_t
    size_ (ACE_Time_Value const* timeout);

    ACE_HANDLE
    get_handle_ ();

  private:
    virtual void
    recv (Message_ptr m);

  private:
    bool loop_;
    Parameters const params_;

    Mutex mutex_;
    Condition cond_;

    ACE_Unbounded_Queue<Message_ptr> queue_;

    ACE_Pipe signal_pipe_;

    ACE_Auto_Ptr<Fragment> fragment_;
    ACE_Auto_Ptr<Reassemble> reassemble_;
    ACE_Auto_Ptr<Acknowledge> acknowledge_;
    ACE_Auto_Ptr<Retransmit> retransmit_;
    ACE_Auto_Ptr<Flow> flow_;
    ACE_Auto_Ptr<Link> link_;
  };


  Socket_Impl::
    Socket_Impl (Address const& a, bool loop, Parameters const& params)
    : loop_ (loop),
    params_ (params),
    cond_ (mutex_)
    {
      fragment_.reset (new Fragment (params_));
      reassemble_.reset (new Reassemble (params_));
      acknowledge_.reset (new Acknowledge (params_));
      retransmit_.reset (new Retransmit (params_));
      flow_.reset (new Flow (params_));
      link_.reset (new Link (a, params_));

      // Start IN stack from top to bottom.
      //
      in_start (0);
      fragment_->in_start (this);
      reassemble_->in_start (fragment_.get ());
      acknowledge_->in_start (reassemble_.get ());
      retransmit_->in_start (acknowledge_.get ());
      flow_->in_start (retransmit_.get ());
      link_->in_start (flow_.get ());

      // Start OUT stack from bottom up.
      //
      link_->out_start (0);
      flow_->out_start (link_.get ());
      retransmit_->out_start (flow_.get ());
      acknowledge_->out_start (retransmit_.get ());
      reassemble_->out_start (acknowledge_.get ());
      fragment_->out_start (reassemble_.get ());
      out_start (fragment_.get ());
    }

  Socket_Impl::
    ~Socket_Impl ()
    {
      // Stop OUT stack from top to bottom.
      //
      out_stop ();
      fragment_->out_stop ();
      reassemble_->out_stop ();
      acknowledge_->out_stop ();
      retransmit_->out_stop ();
      flow_->out_stop ();
      link_->out_stop ();

      // Stop IN stack from bottom up.
      //
      link_->in_stop ();
      flow_->in_stop ();
      retransmit_->in_stop ();
      acknowledge_->in_stop ();
      reassemble_->in_stop ();
      fragment_->in_stop ();
      in_stop ();
    }


  void Socket_Impl::
    send_ (void const* buf, size_t s)
    {
      Message_ptr m (new Message);

      m->add (Profile_ptr (new Data (buf, s)));

      // Qualification is for VC6 and VxWorks.
      //
      Element::send (m);
    }

  ssize_t Socket_Impl::
    recv_ (void* buf,
           size_t s,
           ACE_Time_Value const* timeout,
           ACE_INET_Addr* from)
    {
      ACE_Time_Value abs_time;

      if (timeout)
        abs_time = ACE_OS::gettimeofday () + *timeout;

      Lock l (mutex_);

      while (queue_.is_empty ())
        {
          if (timeout)
            {
              if (cond_.wait (&abs_time) != -1)
                break;
            }
          else
            {
              if (cond_.wait () != -1)
                break;
            }

          return -1; // errno is already set
        }


      Message_ptr m;

      if (queue_.dequeue_head (m) == -1)
        ACE_OS::abort ();


      if (queue_.is_empty ())
        {
          // Remove data from the pipe.
          //
          if (signal_pipe_.read_handle () != ACE_INVALID_HANDLE)
            {
              char c;

              if (signal_pipe_.recv (&c, 1) != 1)
                {
                  ACE_OS::perror ("read: ");
                  ACE_OS::abort ();
                }
            }
        }

      if (from)
        *from = static_cast<From const*> (m->find (From::id))->address ();

      if (m->find (NoData::id) != 0)
        {
          errno = ENOENT;
          return -1;
        }

      Data const* d = static_cast<Data const*>(m->find (Data::id));

      ssize_t r (static_cast<ssize_t> (d->size () < s ? d->size () : s));

      ACE_OS::memcpy (buf, d->buf (), r);

      return r;
    }

  ssize_t Socket_Impl::
    size_ (ACE_Time_Value const* timeout)
    {
      ACE_Time_Value abs_time;

      if (timeout)
        abs_time = ACE_OS::gettimeofday () + *timeout;

      Lock l (mutex_);

      while (queue_.is_empty ())
        {
          if (timeout)
            {
              if (cond_.wait (&abs_time) != -1)
                break;
            }
          else
            {
              if (cond_.wait () != -1)
                break;
            }

          return -1; // errno is already set
        }

      // I can't get the head of the queue without actually dequeuing
      // the element.
      //
      Message_ptr m;

      if (queue_.dequeue_head (m) == -1)
        ACE_OS::abort ();

      if (queue_.enqueue_head (m) == -1)
        ACE_OS::abort ();

      if (m->find (NoData::id) != 0)
        {
          errno = ENOENT;
          return -1;
        }

      Data const* d = static_cast<Data const*>(m->find (Data::id));

      return static_cast<ssize_t> (d->size ());
    }

  ACE_HANDLE Socket_Impl::
    get_handle_ ()
    {
      if (signal_pipe_.read_handle () == ACE_INVALID_HANDLE)
        {
          signal_pipe_.open ();
        }

      return signal_pipe_.read_handle ();
    }


  void Socket_Impl::
    recv (Message_ptr m)
    {
      if (m->find (Data::id) != 0 || m->find (NoData::id) != 0)
        {
          if (!loop_)
            {
              Address to (static_cast<To const*> (m->find (To::id))->address ());

              Address from (
                            static_cast<From const*> (m->find (From::id))->address ());

              if (to == from)
                return;
            }

          Lock l (mutex_);

          //if (queue_.size () != 0)
          //  cerr << "recv socket queue size: " << queue_.size () << endl;

          bool signal (queue_.is_empty ());

          queue_.enqueue_tail (m);

          if (signal)
            {
              // Also write to the pipe.
              if (signal_pipe_.write_handle () != ACE_INVALID_HANDLE)
                {
                  char c;

                  if (signal_pipe_.send (&c, 1) != 1)
                    {
                      // perror ("write: ");
                      ACE_OS::abort ();
                    }
                }

              cond_.signal ();
            }
        }
    }


  // Socket
  //
  //
  Socket::
    ~Socket ()
    {
    }

  Socket::
    Socket (Address const& a, bool loop, Parameters const& params)
    : impl_ (new Socket_Impl (a, loop, params))
    {
    }

  void Socket::
    send (void const* buf, size_t s)
    {
      impl_->send_ (buf, s);
    }

  ssize_t Socket::
    recv (void* buf, size_t s)
    {
      return impl_->recv_ (buf, s, 0, 0);
    }

  ssize_t Socket::
    recv (void* buf, size_t s, ACE_INET_Addr& from)
    {
      return impl_->recv_ (buf, s, 0, &from);
    }

  ssize_t Socket::
    recv (void* buf, size_t s, ACE_Time_Value const& timeout)
    {
      return impl_->recv_ (buf, s, &timeout, 0);
    }

  ssize_t Socket::
    recv (void* buf,
          size_t s,
          ACE_Time_Value const& timeout,
          ACE_INET_Addr& from)
    {
      return impl_->recv_ (buf, s, &timeout, &from);
    }

  ssize_t Socket::
    size ()
    {
      return impl_->size_ (0);
    }

  ssize_t Socket::
    size (ACE_Time_Value const& timeout)
    {
      return impl_->size_ (&timeout);
    }

  ACE_HANDLE Socket::
    get_handle ()
    {
      return impl_->get_handle_ ();
    }
}
