path: root/ace/Local_Tokens.cpp

// Local_Tokens.cpp
// $Id$

#define ACE_BUILD_DLL
#include "ace/Thread.h"
#include "ace/Local_Tokens.h"
#include "ace/Token_Manager.h"

#if !defined (__ACE_INLINE__)
#include "ace/Local_Tokens.i"
#endif /* __ACE_INLINE__ */

void
ACE_Tokens::dump (void) const
{
  ACE_TRACE ("ACE_Tokens::dump");
  ACE_DEBUG ((LM_DEBUG, ACE_BEGIN_DUMP, this));
  ACE_DEBUG ((LM_DEBUG, "ACE_Tokens::dump:\n"
			" reference_cont_ = %d\n"
			" token_name_ = %s\n",
			reference_count_, token_name_));
  ACE_DEBUG ((LM_DEBUG, "waiters_\n"));
  this->waiters_.dump ();
  ACE_DEBUG ((LM_DEBUG, ACE_END_DUMP));
}

ACE_Tokens::ACE_Tokens (void)
  : visited_ (0),
    reference_count_ (0)
{
  ACE_TRACE ("ACE_Tokens::ACE_Tokens");
}

void
ACE_Tokens::make_owner (ACE_TPQ_Entry *caller)
{
  this->waiters_.remove (caller);
  this->waiters_.enqueue (caller, 0);
}

// ************************************************************
// ************************************************************
// ************************************************************


void
ACE_TPQ_Entry::dump (void) const
{
  ACE_TRACE ("ACE_TPQ_Entry::dump");
  ACE_DEBUG ((LM_DEBUG, ACE_BEGIN_DUMP, this));
  ACE_DEBUG ((LM_DEBUG,
	      "ACE_TPQ_Entry::dump:\n"
	      " nesting_level_ = %d\n"
	      " client_id_ = %s\n",
	      nesting_level_,
	      client_id_));

  if (next_ != 0)
    {
      ACE_DEBUG ((LM_DEBUG, "next:.\n"));
      next_->dump ();
    }

  ACE_DEBUG ((LM_DEBUG, "ACE_TPQ_Entry::dump end.\n"));
  ACE_DEBUG ((LM_DEBUG, ACE_END_DUMP));
}

ACE_TPQ_Entry::ACE_TPQ_Entry (const ACE_Token_Proxy *new_proxy,
			      const char *client_id)
  : cond_var_ (lock_),
    next_ (0),
    // This const typecast is safe.
    proxy_ ((ACE_Token_Proxy *) new_proxy),
    nesting_level_ (0),
    sleep_hook_ (0)
{
  ACE_TRACE ("ACE_TPQ_Entry::ACE_TPQ_Entry");

  if (client_id != 0)
    this->client_id (client_id);
  else
    {
      // Just make sure we have enough space.
      char host_name[MAXHOSTNAMELEN];
      char name[(sizeof host_name / sizeof (char)) + 256];
      ACE_OS::hostname (host_name, sizeof host_name);

      ACE_OS::sprintf (name,
		       "/%s/%u/%u",
		       host_name,
		       ACE_OS::getpid (),
		       ACE_Thread::self ());

      this->client_id (name);
    }
}

ACE_TPQ_Entry::ACE_TPQ_Entry (void)
  : cond_var_ (lock_),
    proxy_ (0),
    nesting_level_ (0),
    sleep_hook_ (0)
{
  ACE_TRACE ("ACE_TPQ_Entry::ACE_TPQ_Entry null const.");
}

ACE_TPQ_Entry::ACE_TPQ_Entry (const ACE_TPQ_Entry &rhs)
: cond_var_ (lock_)
{
  ACE_TRACE ("ACE_TPQ_Entry::ACE_TPQ_Entry copy const.");
  *this = rhs;
}

ACE_TPQ_Entry::~ACE_TPQ_Entry (void)
{
  ACE_TRACE ("ACE_TPQ_Entry::~ACE_TPQ_Entry");
}

void
ACE_TPQ_Entry::operator= (const ACE_TPQ_Entry& rhs)
{
  ACE_TRACE ("ACE_TPQ_Entry::operator=");
  if (&rhs == this)
    return;
  this->proxy_ = rhs.proxy ();
  this->nesting_level_ = rhs.nesting_level ();
  this->client_id (rhs.client_id ());
  this->sleep_hook_ = rhs.sleep_hook ();
}

void
ACE_TPQ_Entry::client_id (const char *id)
{
  ACE_TRACE ("ACE_TPQ_Entry::client_id");

  if (id == 0)
    return;

  int n = ACE_OS::strlen (id) + 1;

  if (n >= ACE_MAXCLIENTIDLEN)
    n = ACE_MAXCLIENTIDLEN - 1;

  ACE_OS::strncpy (this->client_id_, (char *) id, n);
  this->client_id_[ACE_MAXCLIENTIDLEN - 1] = '\0';
}

// ************************************************************
// ************************************************************
// ************************************************************

void
ACE_TSS_TPQ_Entry::dump (void) const
{
  ACE_TRACE ("ACE_TSS_TPQ_Entry::dump");
  ACE_DEBUG ((LM_DEBUG, ACE_BEGIN_DUMP, this));
  ACE_DEBUG ((LM_DEBUG, "ACE_TSS_TPQ_Entry::dump:\n"
			" client_id_ = %s\n",
			client_id_ == 0 ? "0" : client_id_));
  ACE_DEBUG ((LM_DEBUG, "base:\n"));
  ACE_TPQ_ENTRY::dump ();
  ACE_DEBUG ((LM_DEBUG, ACE_END_DUMP));
}

ACE_TSS_TPQ_Entry::ACE_TSS_TPQ_Entry (const ACE_Token_Proxy *proxy,
				      const char *client_id)
: proxy_ (proxy),
  client_id_ (client_id)
{
  ACE_TRACE ("ACE_TSS_TPQ_Entry::ACE_TSS_TPQ_Entry");
}

ACE_TPQ_Entry *
ACE_TSS_TPQ_Entry::make_TSS_TYPE (void) const
{
  ACE_TRACE ("ACE_TSS_TPQ_Entry::make_TSS_TYPE");
  ACE_TPQ_Entry *temp;

  ACE_NEW_RETURN (temp, ACE_TPQ_Entry (this->proxy_, this->client_id_), 0);
  return temp;
}

ACE_TSS_TPQ_Entry::operator ACE_TPQ_Entry * (void)
{
  ACE_TRACE ("ACE_TSS_TPQ_Entry::operator");
  return  (ACE_TPQ_Entry *) (*((ACE_TSS<ACE_TPQ_Entry> *) this));
}

// ************************************************************
// ************************************************************
// ************************************************************

ACE_TPQ_Iterator::ACE_TPQ_Iterator (ACE_Token_Proxy_Queue &q)
: current_ (q.head_)
{
  ACE_TRACE ("ACE_TPQ_Iterator::ACE_TPQ_Iterator");
}

int
ACE_TPQ_Iterator::next (ACE_TPQ_Entry *&next_item)
{
  ACE_TRACE ("ACE_TPQ_Iterator::next");

  next_item = this->current_;

  return current_ != 0;
}

int
ACE_TPQ_Iterator::done (void) const
{
  ACE_TRACE ("ACE_TPQ_Iterator::done");

  return this->current_ == 0;
}

void
ACE_TPQ_Iterator::advance (void)
{
  ACE_TRACE ("ACE_TPQ_Iterator::advance");

  if (current_ != 0)
    this->current_ = this->current_->next_;
}

void
ACE_TPQ_Iterator::dump (void) const
{
  ACE_TRACE ("ACE_TPQ_Iterator::dump");
  ACE_DEBUG ((LM_DEBUG, ACE_BEGIN_DUMP, this));
  ACE_DEBUG ((LM_DEBUG, "ACE_TPQ_Iterator::dump:\n"
	      " current_ = %d\n",
	      (long) this->current_));
  ACE_DEBUG ((LM_DEBUG, "head_ and tail_\n"));
  ACE_DEBUG ((LM_DEBUG, ACE_END_DUMP));
}

// ************************************************************
// ************************************************************
// ************************************************************

void
ACE_Token_Proxy_Queue::dump (void) const
{
  ACE_TRACE ("ACE_Token_Proxy_Queue::dump");
  ACE_DEBUG ((LM_DEBUG, ACE_BEGIN_DUMP, this));
  ACE_DEBUG ((LM_DEBUG, "ACE_Token_Proxy_Queue::dump:\n"
			" size_ = %d\n",
			size_));
  ACE_DEBUG ((LM_DEBUG, "head_ and tail_\n"));
  if (this->head_ != 0)
    this->head_->dump ();

  ACE_DEBUG ((LM_DEBUG, "ACE_Token_Proxy_Queue::dump end.\n"));
  ACE_DEBUG ((LM_DEBUG, ACE_END_DUMP));
}

ACE_Token_Proxy_Queue::ACE_Token_Proxy_Queue (void)
  : head_ (0),
    tail_ (0),
    size_ (0)
{
  ACE_TRACE ("ACE_Token_Proxy_Queue::ACE_Token_Proxy_Queue");
}

void
ACE_Token_Proxy_Queue::enqueue (ACE_TPQ_Entry *tpq,
				int position)
{
  ACE_TRACE ("ACE_Token_Proxy_Queue::enqueue");
  tpq->next_ = 0;

  ++this->size_;

  if (this->head_ == 0)
    {
      // make tpq the entire list
      this->head_ = this->tail_ = tpq;
      return;
    }

  if (position == 0)
    {
      // make head of list
      tpq->next_ = this->head_;
      this->head_ = tpq;
      return;
    }

  if (position == -1)
    {
      // stick at back of list
      this->tail_->next_ = tpq;
      this->tail_ = tpq;
      return;
    }

  // walk through list to insertion point
  ACE_TPQ_Entry *temp = head_;

  for (int x = position; x > 1; --x)
    {
      // end of queue?
      if (temp->next_ == 0)
	break;
      // advance pointer
      else
	temp = temp->next_;
    }

  // insert new tpq after temp
  tpq->next_ = temp->next_;
  temp->next_ = tpq;
}

void
ACE_Token_Proxy_Queue::dequeue (void)
{
  ACE_TRACE ("ACE_Token_Proxy_Queue::dequeue");

  if (head_ == 0)
    return;

  ACE_TPQ_Entry *temp = this->head_;

  this->head_ = this->head_->next_;

  temp->next_ = 0;

  --this->size_;

  if (this->head_ == 0 && this->size_ != 0)
    ACE_ERROR ((LM_ERROR, "incorrect size = %d\n", this->size_));
}

/*
int
ACE_Token_Proxy_Queue::member (const char *id)
{
  ACE_TRACE ("ACE_Token_Proxy_Queue::member");

  for (ACE_TPQ_Entry *temp = this->head_; temp != 0; temp = temp->next_)
    if (ACE_OS::strcmp (temp->client_id (), id) == 0)
      // We found it!
      return 1;

  // We didn't find it :-(
  return 0;
}
*/

void
ACE_Token_Proxy_Queue::remove (const ACE_TPQ_Entry *remove_me)
{
  ACE_TRACE ("ACE_Token_Proxy_Queue::remove");
  // sanity
  if ((remove_me == 0) || (this->head_ == 0))
    return;

  // is it the head?
  if (this->head_ == remove_me) // pointer comparison.
    {
      this->head_ = this->head_->next_;
      if (this->head_ == 0)
	this->tail_ = 0;

      --this->size_;
      return;
    }

  ACE_TPQ_Entry *temp = this->head_;
  ACE_TPQ_Entry *previous = 0;

  // is it in the middle or tail?
  while (temp != 0)
    {
      if (temp == remove_me)
	{
	  // previous should never be null since the first if
	  // conditional should always be false
	  previous->next_ = temp->next_;
	  // is it the tail?
	  if (this->tail_ == temp)
	    this->tail_ = previous;

	  --this->size_;
	  return;
	}

      previous = temp;
      temp = temp->next_;
    }

  // it wasn't in the list.
  return;
}

// ************************************************************
// ************************************************************
// ************************************************************

void
ACE_Mutex_Token::dump (void) const
{
  ACE_TRACE ("ACE_Mutex_Token::dump");
  ACE_DEBUG ((LM_DEBUG, ACE_BEGIN_DUMP, this));
  ACE_DEBUG ((LM_DEBUG, "ACE_Mutex_Token::dump:\n"));
  ACE_DEBUG ((LM_DEBUG, "lock_\n"));
  lock_.dump ();
  ACE_DEBUG ((LM_DEBUG, "base:\n"));
  ACE_Tokens::dump ();
  ACE_DEBUG ((LM_DEBUG, "ACE_Mutex_Token::dump end.\n"));
  ACE_DEBUG ((LM_DEBUG, ACE_END_DUMP));
}

ACE_Mutex_Token::ACE_Mutex_Token (const char *name)
{
  ACE_TRACE ("ACE_Mutex_Token::ACE_Mutex_Token");

  int n = ACE_OS::strlen (name) + 1;  // + 1 for \0

  if (n > ACE_MAXTOKENNAMELEN)
    n = ACE_MAXTOKENNAMELEN - 1;

  ACE_OS::strncpy (this->token_name_, name, n);
  this->token_name_[ACE_MAXTOKENNAMELEN - 1] = '\0';
}

ACE_Mutex_Token::~ACE_Mutex_Token (void)
{
  ACE_TRACE ("ACE_Mutex_Token::~ACE_Mutex_Token");
}

int
ACE_Mutex_Token::acquire (ACE_TPQ_Entry *caller,
			  int ignore_deadlock,
			  int notify)
{
  ACE_TRACE ("ACE_Mutex_Token::acquire");
  // We need to acquire two locks. This one to ensure that only one
  // thread uses this token at a time.
  ACE_GUARD_RETURN (ACE_TOKEN_CONST::MUTEX, ace_mon1, this->lock_, -1);
  // This one to ensure an atomic transaction across all tokens.  Note
  // that this order is crucial too.  It's resource coloring for other
  // threads which may be calling this same token.
  ACE_GUARD_RETURN (ACE_TOKEN_CONST::MUTEX, ace_mon2, ACE_Token_Manager::instance ()->mutex (), -1);

  // Does _anyone_ own the token?
  if (this->owner () == 0)
    {
      // there are no waiters, so queue as the first waiter (the owner.)
      this->waiters_.enqueue (caller, -1);
      return 0;  // success
    }

  // Does the caller already own it?
  if (this->is_owner (caller->client_id ()))
    {
      // Recursive acquisition.
      caller->nesting_level (1);
      return 0; // success
    }

  // Check for deadlock.
  if (!ignore_deadlock
      && ACE_Token_Manager::instance ()->check_deadlock (caller->proxy ()) == 1)
    {
      errno = EDEADLK;
      ACE_RETURN (-1);
    }

  // Someone owns it. Sorry, you're getting queued up at the end of
  // the waiter queue.
  this->waiters_.enqueue (caller, -1);

  if (notify)
    this->owner ()->call_sleep_hook ();

  errno = EWOULDBLOCK;
  ACE_RETURN (-1);
}

int
ACE_Mutex_Token::tryacquire (ACE_TPQ_Entry *caller)
{
  ACE_TRACE ("ACE_Mutex_Token::tryacquire");
  // We need to acquire two locks. This one to ensure that only one
  // thread uses this token at a time.
  ACE_GUARD_RETURN (ACE_TOKEN_CONST::MUTEX, ace_mon1, this->lock_, -1);
  // This one to ensure an atomic transaction across all tokens.  Note
  // that this order is crucial too.  It's resource coloring for other
  // threads which may be calling this same token.
  ACE_GUARD_RETURN (ACE_TOKEN_CONST::MUTEX, ace_mon2, ACE_Token_Manager::instance ()->mutex (), -1);

  // Does _anyone_ own the token?
  if (this->owner () == 0)
    {
      this->waiters_.enqueue (caller, -1);
      return 0;  // success
    }
  // Does the caller already own it?
  if (this->is_owner (caller->client_id ()))
    {
      // recursive acquisition
      caller->nesting_level (1);
      return 0;  // success
    }
  else
    // Someone owns it.  Fail.
    {
      errno = EWOULDBLOCK;
      ACE_RETURN (-1);
    }
}

int
ACE_Mutex_Token::renew (ACE_TPQ_Entry *caller,
			int requeue_position)
{
  ACE_TRACE ("ACE_Mutex_Token::renew");
  ACE_GUARD_RETURN (ACE_TOKEN_CONST::MUTEX, ace_mon, this->lock_, -1);

  // Verify that the caller is the owner.
  if (this->is_owner (caller->client_id ()) == 0)
    {
      errno = EACCES;
      ACE_RETURN (-1);
    }

  // The caller is the owner, so check to see if there are any
  // waiters.  If not, we just keep the token.  == 1 means that there
  // is only the owner.
  if (this->waiters_.size () == 1 || requeue_position == 0)
    return 0;

  // Requeue the caller.
  this->waiters_.dequeue ();

  this->waiters_.enqueue (caller, requeue_position);

  // Notify new owner.
  if (this->owner () != 0)
    this->owner ()->proxy ()->token_acquired (this->owner ());

  // Tell the caller that the operation would block.
  errno = EWOULDBLOCK;
  ACE_RETURN (-1);
}

// Release the current holder of the token (which had
// better be the caller's thread!).

int
ACE_Mutex_Token::release (ACE_TPQ_Entry *caller)
{
  ACE_TRACE ("ACE_Mutex_Token::release");
  ACE_GUARD_RETURN (ACE_TOKEN_CONST::MUTEX, ace_mon, this->lock_, -1);

  // Does anyone own the token?
  if (this->owner () == 0)
    {
      errno = EACCES;
      ACE_RETURN (-1);
    }

  // Is the caller the owner.
  if (this->is_owner (caller->client_id ()))
    {
      // Check the nesting level.
      if (caller->nesting_level () > 0)
	caller->nesting_level (-1);
      else
	{
	  this->waiters_.dequeue ();
	  // Notify new owner.
	  if (this->owner () != 0)
	    this->owner ()->proxy ()->token_acquired (this->owner ());
	}
    }
  else
    this->remove (caller);

  return 0;
}

int
ACE_Mutex_Token::owners (OWNER_STACK &stack,
			 const char *id)
{
  ACE_TRACE ("ACE_Mutex_Token::owners");
  if (this->owner () != 0)
    {
      stack.push (this->owner ());
      // If an <id> is specified, return whether it is the owner being
      // returned.
      if (id != 0)
	return this->owner ()->equal_client_id (id);
    }

  return 0;
}

int
ACE_Mutex_Token::is_waiting_for (const char *id)
{
  ACE_TRACE ("ACE_Mutex_Token::is_waiting_for");
  // If there is no owner, or <id> is the owner, return false.
  if ((this->owner () == 0) || this->is_owner (id))
    return 0;

  // Step through each waiter looking for <id>.
  ACE_TPQ_Iterator iterator (waiters_);
  iterator.advance ();
  for (ACE_TPQ_Entry *temp = 0;
       iterator.next (temp) != 0;
       iterator.advance ())
    {
      if (temp->equal_client_id (id))
	return 1;
    }

  return 0;
}

int
ACE_Mutex_Token::is_owner (const char *id)
{
  ACE_TRACE ("ACE_Mutex_Token::is_owner");
  // If there is an owner, return whether it is <id>.
  if ((this->owner () != 0) &&
      this->owner ()->equal_client_id (id))
    return 1;
  else
    return 0;
}

// ************************************************************
// ************************************************************
// ************************************************************

void
ACE_RW_Token::dump (void) const
{
  ACE_TRACE ("ACE_RW_Token::dump");
  ACE_DEBUG ((LM_DEBUG, ACE_BEGIN_DUMP, this));
  ACE_DEBUG ((LM_DEBUG, "ACE_RW_Token::dump:\n"
			"num_writers_ = %d\n", num_writers_));
  ACE_DEBUG ((LM_DEBUG, "lock_\n"));
  this->lock_.dump ();
  ACE_DEBUG ((LM_DEBUG, "base:\n"));
  ACE_Tokens::dump ();
  ACE_DEBUG ((LM_DEBUG, "ACE_RW_Token::dump end.\n"));
  ACE_DEBUG ((LM_DEBUG, ACE_END_DUMP));
}

ACE_RW_Token::ACE_RW_Token (const char *name)
: num_writers_ (0)
{
  ACE_TRACE ("ACE_RW_Token::ACE_RW_Token");

  int n = ACE_OS::strlen (name) + 1;  // + 1 for \0

  if (n > ACE_MAXTOKENNAMELEN)
    n = ACE_MAXTOKENNAMELEN;

  ACE_OS::strncpy (this->token_name_, name, n);
  this->token_name_[ACE_MAXTOKENNAMELEN - 1] = '\0';
}

ACE_RW_Token::~ACE_RW_Token (void)
{
  ACE_TRACE ("ACE_RW_Token::~ACE_RW_Token");
}

int
ACE_RW_Token::acquire (ACE_TPQ_Entry *caller,
		       int ignore_deadlock,
		       int notify)
{
  ACE_TRACE ("ACE_RW_Token::acquire");
  // We need to acquire two locks. This one to ensure that only one
  // thread uses this token at a time.
  ACE_GUARD_RETURN (ACE_TOKEN_CONST::MUTEX, ace_mon1, this->lock_, -1);
  // This one to ensure an atomic transaction across all tokens.  Note
  // that this order is crucial too.  It's resource coloring for other
  // threads which may be calling this same token.
  ACE_GUARD_RETURN (ACE_TOKEN_CONST::MUTEX, ace_mon2, ACE_Token_Manager::instance ()->mutex (), -1);

  if (caller->proxy ()->type () == ACE_RW_Token::WRITER)
    this->num_writers_++;

  // Does _anyone_ own the token?
  if (this->owner () == 0)
    {
      // There are no waiters, so queue as the first waiter (the owner).
      this->waiters_.enqueue (caller, -1);
      return 0;
    }

  // Check for recursive acquisition.
  if (this->is_owner (caller->client_id ()))
    {
      caller->nesting_level (1);
      return 0;  // Success.
    }

  // Reader.
  if (caller->proxy ()->type () == ACE_RW_Token::READER)
    {
      // Are there any writers?
      if (this->num_writers_ == 0)
	{
	  // Queue the caller at the end of the queue.
	  this->waiters_.enqueue (caller, -1);
	  return 0;
	}
      // Else failure.
    }

  // Failure code.

  // Check for deadlock.
  if (!ignore_deadlock &&
      ACE_Token_Manager::instance ()->check_deadlock (caller->proxy ()) == 1)
    {
      if (caller->proxy ()->type () == ACE_RW_Token::WRITER)
	this->num_writers_--;
      errno = EDEADLK;
      ACE_RETURN (-1);
    }

  // Queue the caller at the end of the queue.
  this->waiters_.enqueue (caller, -1);

  if (notify)
    {
      // If it's a writer, just notify it.
      if (this->owner ()->proxy ()->type () == ACE_RW_Token::WRITER)
	this->owner ()->call_sleep_hook ();
      else
	{
	  // Call back all reader owners.
	  ACE_TPQ_Entry *temp = this->owner ();
	  do
	    {
	      temp->call_sleep_hook ();
	      temp = temp->next_;
	    }
	  while (temp != 0 &&
		 temp->proxy ()->type () == ACE_RW_Token::READER);
	}
    }

  errno = EWOULDBLOCK;
  ACE_RETURN (-1);
}

int
ACE_RW_Token::tryacquire (ACE_TPQ_Entry *caller)
{
  ACE_TRACE ("ACE_RW_Token::tryacquire");
  // We need to acquire two locks. This one to ensure that only one
  // thread uses this token at a time.
  ACE_GUARD_RETURN (ACE_TOKEN_CONST::MUTEX, ace_mon1, this->lock_, -1);
  // This one to ensure an atomic transaction across all tokens.  Note
  // that this order is crucial too.  It's resource coloring for other
  // threads which may be calling this same token.
  ACE_GUARD_RETURN (ACE_TOKEN_CONST::MUTEX, ace_mon2, ACE_Token_Manager::instance ()->mutex (), -1);

  if (caller->proxy ()->type () == ACE_RW_Token::WRITER)
    {
      this->num_writers_++;
    }

  // Does _anyone_ own the token?
  if (this->owner () == 0)
    {
      // There are no waiters, so queue as the first waiter (the owner).
      this->waiters_.enqueue (caller, -1);
      return 0;
    }

  // Check for recursive acquisition.
  if (this->is_owner (caller->client_id ()))
    {
      caller->nesting_level (1);
      return 0;  // Success.
    }

  // Reader.
  if (caller->proxy ()->type () == ACE_RW_Token::READER)
    {
      // Are there any writers?
      if (this->num_writers_ == 0)
	{
	  // queue the caller at the end of the queue.
	  this->waiters_.enqueue (caller, -1);
	  return 0;
	}
      // Else, fail.
    }
  else // Writer.
    // We're going to fail, so decrement the num_writers.
    {
      this->num_writers_--;
    }


  errno = EWOULDBLOCK;
  ACE_RETURN (-1);
}

int
ACE_RW_Token::renew (ACE_TPQ_Entry *caller,
		     int requeue_position)
{
  ACE_TRACE ("ACE_RW_Token::renew");
  ACE_GUARD_RETURN (ACE_TOKEN_CONST::MUTEX, ace_mon, this->lock_, -1);

  // Werify that the caller is the owner
  if (this->is_owner (caller->client_id ()) == 0)
    {
      errno = EACCES;
      ACE_RETURN (-1);
    }

  // The caller is the owner, so check to see if there are any
  // waiters.  If not, we just keep the token.
  if (this->waiters_.size () == 1 || requeue_position == 0)
    return 0;

  // There are waiters, so remove the caller.
  this->remove (caller);

  // Requeue the caller.
  this->waiters_.enqueue (caller, requeue_position);

  if (caller->proxy ()->type () == ACE_RW_Token::READER)
    {
      // If the caller got queued before any writers, the caller is
      // still the owner.
      if (this->is_owner (caller->client_id ()))
	return 0; // success
      // else fallthrough and return would block.
    }
  // Writers will always have to block since waiters_.size () == 1 or
  // requeue_position == 0.

  // Get a new owner.
  this->notify_new_owner (caller);

  // Tell the caller that the operation would block.
  errno = EWOULDBLOCK;
  ACE_RETURN (-1);
}

int
ACE_RW_Token::release (ACE_TPQ_Entry *caller)
{
  ACE_TRACE ("ACE_RW_Token::release");
  ACE_GUARD_RETURN (ACE_TOKEN_CONST::MUTEX, ace_mon, this->lock_, -1);

  // Check for errors.
  if ((this->owner () == 0) ||
      (this->is_owner (caller->client_id ()) == 0))
    {
      errno = EACCES;
      ACE_RETURN (-1);
    }

  if (caller->proxy ()->type () == ACE_RW_Token::WRITER)
    num_writers_--;

  // Recursive release.
  if (caller->nesting_level () > 0)
    {
      caller->nesting_level (-1);
      return 0;
    }

  // Remove the caller and notify the new owner(s).
  this->remove (caller);
  this->notify_new_owner (caller);

  return 0;
}

void
ACE_RW_Token::notify_new_owner (ACE_TPQ_Entry *old_owner)
{
  ACE_TRACE ("ACE_RW_Token::new_owner");

  if (this->owner () == 0)
    return;

  if (this->owner ()->proxy ()->type () == ACE_RW_Token::READER)
    {
      if (old_owner->proxy ()->type () == ACE_RW_Token::READER)
	// the owners already know that they're owners
	return;

      // The current owner is a reader and the previous owner was a
      // writer, so notify all waiting readers up to the first writer.
      // call back all reader owners.
      ACE_TPQ_Iterator iterator (waiters_);
      for (ACE_TPQ_Entry *temp = 0;
	   iterator.next (temp) != 0;
	   iterator.advance ())
	{
	  if (temp->proxy ()->type () == WRITER)
	    // We've gone through all the readers.
	    break;

	  temp->proxy ()->token_acquired (temp);
	}
    }
  else // writer
    this->owner ()->proxy ()->token_acquired (this->owner ());
}


int
ACE_RW_Token::owners (OWNER_STACK &stack,
		      const char *id)
{
  ACE_TRACE ("ACE_RW_Token::owners");

  if (this->owner () == 0)
    return 0;

  int id_is_owner = 0;

  // The first waiter is a writer, so there is only one owner.
  if (this->owner ()->proxy ()->type () == WRITER)
    {
      stack.push (this->owner ());
      // If an <id> is specified, return whether it is the owner being
      // returned.
      if ((id != 0) &&
	  (ACE_OS::strcmp (id, this->owner ()->client_id ()) == 0))
	id_is_owner = 1;
    }
  // The first waiter is a reader, so there can be multiple owning
  // readers.
  else
    {
      ACE_TPQ_Iterator iterator (waiters_);
      for (ACE_TPQ_Entry *temp = 0;
	   iterator.next (temp) != 0;
	   iterator.advance ())
	{
	  if (temp->proxy ()->type () == WRITER)
	    // We've gone through all the readers.
	    break;

	  stack.push (temp);

	  if (!id_is_owner && (id != 0) &&
	      (ACE_OS::strcmp (id, temp->client_id ()) == 0))
	    id_is_owner = 1;
	}
    }

  return id_is_owner;
}

int
ACE_RW_Token::is_waiting_for (const char *id)
{
  ACE_TRACE ("ACE_RW_Token::is_waiting_for");
  // If there is no owner, or <id> is the owner, return false.
  if ((this->owner () == 0) ||
      this->is_owner (id))
    return 0;

  // Step through each waiter looking for <id>.
  ACE_TPQ_Iterator iterator (waiters_);
  iterator.advance ();
  for (ACE_TPQ_Entry *temp = 0;
       iterator.next (temp) != 0;
       iterator.advance ())
    {
      if (temp->equal_client_id (id))
	return 1;
    }

  return 0;
}

int
ACE_RW_Token::is_owner (const char *id)
{
  ACE_TRACE ("ACE_Mutex_Token::is_owner");
  // If there is no owner, return false.
  if (this->owner () == 0)
    return 0;

  // A writer owns us.
  if (this->owner ()->proxy ()->type () == ACE_RW_Token::WRITER)
    return this->owner ()->equal_client_id (id);

  // Readers own us.
  // Step through each owning reader looking for <id>.
  ACE_TPQ_Iterator iterator (waiters_);
  for (ACE_TPQ_Entry *temp = 0;
       iterator.next (temp) != 0;
       iterator.advance ())
    {
      if (temp->proxy ()->type () != ACE_RW_Token::READER)
	break;

      if (temp->equal_client_id (id))
	return 1;
    }

  return 0;
}

// ************************************************************
// ************************************************************
// ************************************************************
// 7..

void
ACE_Token_Proxy::dump (void) const
{
  ACE_TRACE ("ACE_Token_Proxy::dump");
  ACE_DEBUG ((LM_DEBUG, ACE_BEGIN_DUMP, this));
  ACE_DEBUG ((LM_DEBUG, "ACE_Token_Proxy::dump:\n"
			" type = %d\n"
			" ignore_deadlock_ = %d\n"
			" debug_ = %d\n",
			(int) this->type (), ignore_deadlock_, debug_));
  ACE_DEBUG ((LM_DEBUG, "mutex_, and waiter_\n"));

  if (this->token_ != 0)
    this->token_->dump ();

  this->waiter_.dump ();
  ACE_DEBUG ((LM_DEBUG, "ACE_Token_Proxy::dump end.\n"));
  ACE_DEBUG ((LM_DEBUG, ACE_END_DUMP));
}

const char*
ACE_Token_Proxy::client_id (void) const
{
  ACE_TRACE ("ACE_Token_Proxy::client_id");
  // Thread-specific.
  const char *id = this->waiter_->client_id ();

  if (id == 0)
    return "ERROR NO CLIENT ID";
  else
    return id;
}

void
ACE_Token_Proxy::client_id (const char *client_id)
{
  ACE_TRACE ("ACE_Token_Proxy::client_id");
  this->waiter_->client_id (client_id);
}

const char *
ACE_Token_Proxy::owner_id (void)
{
  ACE_TRACE ("ACE_Token_Proxy::owner_id");
  return this->token_->owner_id ();
}

const char *
ACE_Token_Proxy::name (void) const
{
  ACE_TRACE ("ACE_Token_Proxy::owner_id");
  return this->token_->name ();
}

ACE_Token_Proxy::ACE_Token_Proxy (void)
: token_ (0),
  waiter_ (this, 0)
{
  ACE_TRACE ("ACE_Token_Proxy::ACE_Token_Proxy");
}

// Notice the token_ (0).  Do *not* copy the token pointer.  This must
// be obtained through the token manager.  Also, we don't copy any
// waiter info.  A copied Proxy does *not* inherit client_id.

ACE_Token_Proxy::ACE_Token_Proxy (const ACE_Token_Proxy &)
  : token_ (0),
    waiter_ (this, 0)
{
  ACE_TRACE ("ACE_Token_Proxy::ACE_Token_Proxy");
}

// @@ should I do a mutex_->release ()?
ACE_Token_Proxy::~ACE_Token_Proxy (void)
{
  ACE_TRACE ("ACE_Local_Mutex::~ACE_Local_Mutex");

  if (token_ != 0)
    // notify token manager that we are done with it so it can
    // free it if necessary
    ACE_Token_Manager::instance ()->release_token (token_);
}

int
ACE_Token_Proxy::open (const char *token_name,
		       int ignore_deadlock,
		       int debug)
{
  ACE_TRACE ("ACE_Token_Proxy::open");

  // Store some parameters.
  this->ignore_deadlock_ = ignore_deadlock;
  this->debug_ = debug;

  // Used in case a name was not specified.
  char name[BUFSIZ];

  // We must have a name.
  if (token_name == 0)
    {
      ACE_OS::sprintf (name, "token %d", this);
      token_name = name;
    }

  // Get or create the underlying token.  The Token Manager will call
  // us back to set token_.
  ACE_Token_Manager::instance ()->get_token (this, token_name);

  // Check for failed get or failed new.
  if (this->token_ == 0)
    {
      errno = ENOMEM;
      ACE_ERROR_RETURN ((LM_ERROR, "Can't allocate mutex"), -1);
    }

  return 0;
}

int
ACE_Token_Proxy::acquire (int notify,
			  void (*sleep_hook)(void *),
			  ACE_Synch_Options &options)
{
  ACE_TRACE ("ACE_Token_Proxy::acquire");
  if (this->token_ == 0)
    {
      errno = ENOENT;
      ACE_ERROR_RETURN ((LM_ERROR, "Not open.\n"), -1);
    }

  // Make sure no one calls our token_acquired until we have a chance
  // to sleep first!  If after we call an EWOULDBLOCK
  // mutex_->acquire() below, but before we enter handle_options to
  // wait on the cond_var, a thread tries to give take us off the
  // waiter queue and signal us, IT WILL FIRST HAVE TO ACQUIRE THIS
  // cond_var.mutex ().  _This_ is why we acquire it.
  this->waiter_->cond_var_.mutex ().acquire ();

  this->waiter_->sleep_hook (sleep_hook);

  if (this->token_->acquire (this->waiter_, this->ignore_deadlock_, notify) == -1)
    // acquire failed
    {
      switch (errno)
	{
	case EDEADLK :
	  if (!ignore_deadlock_)
	    {
	      waiter_->cond_var_.mutex ().release ();
	      errno = EDEADLK;
	      ACE_RETURN (-1);
	    }
	  // Else, fallthrough and block!

	case EWOULDBLOCK :
	  if (this->debug_)
	    ACE_DEBUG ((LM_DEBUG,
			"(%t) waiting for %s, owner is %s, "
			"total waiters == %d\n",
			this->name (),
			this->token_->owner_id (),
			token_->no_of_waiters ()));

	  // no error, but would block,
	  // if error, return error (-1), otherwise, return whether we
	  // called the holder or not.
	  int return_value;
	  if (this->handle_options (options, waiter_->cond_var_) == -1)
	    return_value = -1;
	  else
	    return_value = notify == 1;

	  errno = EWOULDBLOCK;
	  ACE_RETURN (return_value);

	default :
	  waiter_->cond_var_.mutex ().release ();
	  ACE_ERROR_RETURN ((LM_ERROR,
			     "%p\n","Token Proxy acquire."), -1);
	}
    }
  else
    // we have the token
    {
      if (debug_)
	ACE_DEBUG ((LM_DEBUG, "(%t) acquired %s\n",
		    this->name ()));
      waiter_->cond_var_.mutex ().release ();
    }

  return 0;
}

int
ACE_Token_Proxy::tryacquire (void (*sleep_hook)(void *))
{
  ACE_TRACE ("ACE_Token_Proxy::tryacquire");
  if (this->token_ == 0)
    {
      errno = ENOENT;
      ACE_ERROR_RETURN ((LM_ERROR, "Not open.\n"), -1);
    }

  this->waiter_->sleep_hook (sleep_hook);

  return this->token_->tryacquire (waiter_);
}

int
ACE_Token_Proxy::renew (int requeue_position,
			ACE_Synch_Options &options)
{
  ACE_TRACE ("ACE_Token_Proxy::renew");
  if (this->token_ == 0)
    {
      errno = ENOENT;
      ACE_ERROR_RETURN ((LM_ERROR, "Not open.\n"), -1);
    }

  // Make sure no one calls our token_acquired until we have a chance
  // to sleep first!
  this->waiter_->cond_var_.mutex ().acquire ();

  if (this->token_->renew (this->waiter_, requeue_position) == -1)
    {
      // check for error
      if (errno != EWOULDBLOCK)
	ACE_ERROR_RETURN ((LM_ERROR,
			   "%p renew failed\n", "ACE_Token_Proxy"), -1);

      if (this->debug_)
	ACE_DEBUG ((LM_DEBUG, "(%t) renew blocking for %s, owner is %s\n",
		    this->name (),
		    token_->owner_id ()));

      // no error, but would block, so block or return
      return this->handle_options (options, waiter_->cond_var_);
    }
  else
    // we have the token
    {
      if (this->debug_)
	ACE_DEBUG ((LM_DEBUG, "(%t) renewed %s\n",
		    this->name ()));
      waiter_->cond_var_.mutex ().release ();
      return 0;
    }
}

int
ACE_Token_Proxy::handle_options (ACE_Synch_Options &options,
				 ACE_TOKEN_CONST::COND_VAR &cv)
{
  // Some operation failed with EWOULDBLOCK.
  ACE_TRACE ("ACE_Token_Proxy::handle_options");

  if (options[ACE_Synch_Options::USE_REACTOR] == 1)
    // Asynchronous.
    {
      int error = errno;
      // if (options[ACE_Synch_Options::USE_TIMEOUT] == 1)
      // ACE_ERROR_RETURN ((LM_ERROR, "Timeouts not yet supported" "
      // with asynchronous operations."), -1);
      cv.mutex ().release ();
      errno = error;
      ACE_RETURN (-1);
    }
  else
    // Synchronous.
    {
      // Block on condition variable.
      while (cv.wait ((ACE_Time_Value *) options.time_value ()) == -1)
	{
	  // Note, this should obey whatever thread-specific
	  // interrupt policy is currently in place...
	  if (errno == EINTR)
	    continue;
	  // We come here if a timeout occurs or some serious
	  // ACE_Condition object error.
	  cv.mutex ().release ();
	  ACE_ERROR_RETURN ((LM_ERROR, "condition variable wait"
			     " bombed."), -1);
	}

      if (this->debug_)
	ACE_DEBUG ((LM_DEBUG, "(%t) unblocking.\n",
		    this->client_id ()));
      cv.mutex ().release ();
      return 0;       // operation succeeded
    }
}

int
ACE_Token_Proxy::release (ACE_Synch_Options &)
{
  ACE_TRACE ("ACE_Token_Proxy::release");

  if (this->token_ == 0)
    {
      errno = ENOENT;
      if (debug_)
	ACE_DEBUG ((LM_DEBUG, "Must open before releasing.\n"));
      ACE_RETURN (-1);
    }

  if (this->token_->release (waiter_) != 0)
    {
      // Release failed.
      this->token_->remove (this->waiter_);
      if (debug_)
	ACE_DEBUG ((LM_DEBUG, "(%t) %p.\n", "release failed"));
      return -1;
    }
  else
    {
      if (this->debug_)
	ACE_DEBUG ((LM_DEBUG, "(%t) released %s, owner is %s\n",
		    this->name (),
		    token_->owner_id ()));

      return 0;
    }
}

int
ACE_Token_Proxy::remove (ACE_Synch_Options &)
{
  ACE_TRACE ("ACE_Token_Proxy::remove");
  return 0;
}

void
ACE_Token_Proxy::sleep_hook (void)
{
  ACE_TRACE ("ACE_Token_Proxy::sleep_hook");
  // Somebody wants our token!  (Let'em wait...)
  return;
}

void
ACE_Token_Proxy::token_acquired (ACE_TPQ_Entry *e)
{
  ACE_TRACE ("ACE_Token_Proxy::token_acquired");
  e->cond_var_.mutex ().acquire ();
  // We've been taken off the waiters list and given the token!
  // This implementation signals the internal condition
  // variable. Thus, if asynchronous acquires are used, this must be
  // overriden to do something more useful!
  e->cond_var_.signal ();
  e->cond_var_.mutex ().release ();

  return;
}

// ************************************************************

ACE_Token_Name::ACE_Token_Name (const char *token_name)
{
  ACE_TRACE ("ACE_Token_Name::ACE_Token_Name");
  this->name (token_name);
}

ACE_Token_Name::ACE_Token_Name (const ACE_Token_Name &rhs)
{
  ACE_TRACE ("ACE_Token_Name::ACE_Token_Name");
  this->name (rhs.name ());
}

ACE_Token_Name::~ACE_Token_Name ()
{
  ACE_TRACE ("ACE_Token_Name::~ACE_Token_Name");
}

void
ACE_Token_Name::dump (void) const
{
  ACE_TRACE ("ACE_Token_Name::dump");
  ACE_DEBUG ((LM_DEBUG, ACE_BEGIN_DUMP, this));
  ACE_DEBUG ((LM_DEBUG, "ACE_Token_Name::dump:\n"
			" token_name_ = %s\n",
	      token_name_ == 0 ? "no name" : token_name_));
  ACE_DEBUG ((LM_DEBUG, ACE_END_DUMP));
}


#if defined (ACE_HAS_EXPLICIT_TEMPLATE_INSTANTIATION)
#if !defined (ACE_NO_TSS_TOKENS)
template class ACE_TSS <ACE_TPQ_Entry>;
#endif /* ACE_NO_TSS_TOKENS */
template class ACE_Unbounded_Stack <ACE_TPQ_Entry *>;
template class ACE_Node <ACE_TPQ_Entry *>;
#elif defined (ACE_HAS_TEMPLATE_INSTANTIATION_PRAGMA)
#if !defined (ACE_NO_TSS_TOKENS)
#pragma instantiate ACE_TSS <ACE_TPQ_Entry>
#endif /* ACE_NO_TSS_TOKENS */
#pragma instantiate ACE_Unbounded_Stack <ACE_TPQ_Entry *>
#pragma instantiate ACE_Node <ACE_TPQ_Entry *>
#endif /* ACE_HAS_EXPLICIT_TEMPLATE_INSTANTIATION */