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// $Id$
#include "Leader_Follower.h"
#include "Resource_Factory.h"
#include "ace/Reactor.h"
#if !defined (__ACE_INLINE__)
# include "Leader_Follower.i"
#endif /* ! __ACE_INLINE__ */
ACE_RCSID(tao, Leader_Follower, "$Id$")
TAO_Leader_Follower::~TAO_Leader_Follower (void)
{
// Hand the reactor back to the resource factory.
this->orb_core_->resource_factory ()->reclaim_reactor (this->reactor_);
this->reactor_ = 0;
}
TAO_Leader_Follower::TAO_Follower_Node::TAO_Follower_Node (TAO_SYNCH_CONDITION* follower_ptr)
: follower_ (follower_ptr),
next_ (0)
{
}
TAO_Leader_Follower::TAO_Follower_Queue::TAO_Follower_Queue (void)
: head_ (0),
tail_ (0)
{
}
int
TAO_Leader_Follower::TAO_Follower_Queue::insert (TAO_Follower_Node* node)
{
if (this->head_ == 0) {
this->head_ = node;
this->tail_ = node;
// Make sure that we don't have garbage in the case when the same node
// is added a second time. This is necessary as the nodes are on the
// stack.
node->next_ = 0;
}
else
{
// Add the node to the tail and modify the pointers
TAO_Follower_Node* temp = this->tail_;
temp->next_ = node;
this->tail_ = node;
node->next_ = 0;
}
return 0;
}
int
TAO_Leader_Follower::TAO_Follower_Queue::remove (TAO_Follower_Node* node)
{
TAO_Follower_Node* prev = 0;
TAO_Follower_Node* curr = 0;
// No followers in queue, return
if (this->head_ == 0)
return -1;
// Check is for whether we have the same condition variable on the
// queue rather than the same node structure which wraps it.
for (curr = this->head_;
curr != 0 && curr->follower_ != node->follower_;
curr = curr->next_)
{
prev = curr;
}
// Entry not found in the queue
if (curr == 0)
return -1;
// Entry found at the head of the queue
else if (prev == 0)
this->head_ = this->head_->next_;
else
prev->next_ = curr->next_;
// Entry at the tail
if (curr->next_ == 0)
this->tail_ = prev;
return 0;
}
TAO_SYNCH_CONDITION*
TAO_Leader_Follower::get_next_follower (void)
{
// If the queue is empty return
if (this->follower_set_.is_empty())
return 0;
TAO_Follower_Node* next_follower = this->follower_set_.head_;
TAO_SYNCH_CONDITION *cond = next_follower->follower_;
#if defined (TAO_DEBUG_LEADER_FOLLOWER)
ACE_DEBUG ((LM_DEBUG,
"TAO (%P|%t) LF::get_next_follower - "
"follower is %x\n",
cond));
#endif /* TAO_DEBUG_LEADER_FOLLOWER */
// We *must* remove it when we signal it so the same condition is
// not signalled for both wake up as a follower and as the next
// leader.
// The follower may not be there if the reply is received while the
// consumer is not yet waiting for it (i.e. it send the request but
// has not blocked to receive the reply yet)
(void) this->remove_follower (next_follower); // Ignore errors..
return cond;
}
int
TAO_Leader_Follower::wait_for_client_leader_to_complete (ACE_Time_Value *max_wait_time)
{
int result = 0;
ACE_Countdown_Time countdown (max_wait_time);
// Note that we are waiting.
++this->event_loop_threads_waiting_;
while (this->client_thread_is_leader_ &&
result != -1)
{
if (max_wait_time == 0)
{
if (this->event_loop_threads_condition_.wait () == -1)
{
ACE_ERROR ((LM_ERROR,
ACE_TEXT ("TAO (%P|%t): TAO_Leader_Follower::wait_for_client_leader_to_complete - ")
ACE_TEXT ("Condition variable wait failed\n")));
result = -1;
}
}
else
{
countdown.update ();
ACE_Time_Value tv = ACE_OS::gettimeofday ();
tv += *max_wait_time;
if (this->event_loop_threads_condition_.wait (&tv) == -1)
{
if (errno != ETIME)
ACE_ERROR ((LM_ERROR,
ACE_TEXT ("TAO (%P|%t): TAO_Leader_Follower::wait_for_client_leader_to_complete - ")
ACE_TEXT ("Condition variable wait failed\n")));
result = -1;
}
}
}
// Reset waiting state.
--this->event_loop_threads_waiting_;
return result;
}
ACE_Reactor *
TAO_Leader_Follower::reactor (void)
{
if (this->reactor_ == 0)
{
ACE_GUARD_RETURN (TAO_SYNCH_MUTEX, ace_mon, this->lock (), 0);
if (this->reactor_ == 0)
{
this->reactor_ =
this->orb_core_->resource_factory ()->get_reactor ();
}
}
return this->reactor_;
}
void
TAO_Leader_Follower::set_client_thread (void)
{
// If we were a leader thread or an event loop thread, give up
// leadership.
TAO_ORB_Core_TSS_Resources *tss = this->get_tss_resources ();
if (tss->event_loop_thread_ ||
tss->client_leader_thread_)
{
--this->leaders_;
}
if (this->clients_ == 0 &&
this->orb_core_->has_shutdown ())
{
// The ORB has shutdown and we are the first client after
// that. This means that the reactor is disabled, we must
// re-enable it if we want to receive any replys...
this->orb_core_->reactor ()->reset_reactor_event_loop ();
}
this->clients_++;
}
void
TAO_Leader_Follower::reset_client_thread (void)
{
// If we were a leader thread or an event loop thread, take back
// leadership.
TAO_ORB_Core_TSS_Resources *tss = this->get_tss_resources ();
if (tss->event_loop_thread_ ||
tss->client_leader_thread_)
{
++this->leaders_;
}
this->clients_--;
if (this->clients_ == 0 && this->orb_core_->has_shutdown ())
{
// The ORB has shutdown and we are the last client thread, we
// must stop the reactor to ensure that any server threads go
// away.
this->orb_core_->reactor ()->end_reactor_event_loop ();
}
}
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