diff options
Diffstat (limited to 'ace/Future.cpp')
| -rw-r--r-- | ace/Future.cpp | 224 |
1 files changed, 96 insertions, 128 deletions
diff --git a/ace/Future.cpp b/ace/Future.cpp index 7c5fd9b29af..eccf2ef6e0b 100644 --- a/ace/Future.cpp +++ b/ace/Future.cpp @@ -17,13 +17,14 @@ ACE_Future_Rep<T>::dump (void) const { ACE_DEBUG ((LM_DEBUG, ACE_BEGIN_DUMP, this)); ACE_DEBUG ((LM_DEBUG, - "ref_count_ = %d\n", - (int) this->ref_count_)); + "ref_count_ = %d\n", + (int) this->ref_count_)); ACE_DEBUG ((LM_INFO,"value_: \n")); if (this->value_) ACE_DEBUG ((LM_DEBUG," (NON-NULL)\n")); else ACE_DEBUG ((LM_DEBUG," (NULL)\n")); + ACE_DEBUG ((LM_INFO,"value_ready_: \n")); this->value_ready_.dump (); ACE_DEBUG ((LM_INFO,"value_ready_mutex_: \n")); @@ -31,6 +32,62 @@ ACE_Future_Rep<T>::dump (void) const ACE_DEBUG ((LM_DEBUG, ACE_END_DUMP)); } +template <class T> ACE_Future_Rep<T> * +ACE_Future_Rep<T>::create (void) +{ + // Yes set ref count to zero. + return new ACE_Future_Rep<T>(); +} + +template <class T> ACE_Future_Rep<T> * +ACE_Future_Rep<T>::attach (ACE_Future_Rep<T>*& rep) +{ + ACE_ASSERT (rep != 0); + // Use value_ready_mutex_ for both condition and ref count management + ACE_MT (ACE_Guard<ACE_Thread_Mutex> r_mon(rep->value_ready_mutex_)); + ++rep->ref_count_; + return rep; +} + +template <class T> void +ACE_Future_Rep<T>::detach (ACE_Future_Rep<T>*& rep) +{ + ACE_ASSERT(rep != 0); + // Use value_ready_mutex_ for both condition and ref count management + ACE_MT (ACE_GUARD (ACE_Thread_Mutex, r_mon, rep->value_ready_mutex_)); + + if (rep->ref_count_-- == 0) + { + r_mon.release (); + // We do not need the lock when deleting the representation. + // There should be no side effects from deleting rep and we don + // not want to release a deleted mutex. + delete rep; + } +} + +template <class T> void +ACE_Future_Rep<T>::assign (ACE_Future_Rep<T>*& rep, ACE_Future_Rep<T>* new_rep) +{ + ACE_ASSERT(rep != 0); + ACE_ASSERT(new_rep != 0); + // Use value_ready_mutex_ for both condition and ref count management + ACE_MT (ACE_GUARD (ACE_Thread_Mutex, r_mon, rep->value_ready_mutex_)); + + ACE_Future_Rep<T>* old = rep; + rep = new_rep; + + // detached old last for exception safety + if (old->ref_count_-- == 0) + { + r_mon.release (); + // We do not need the lock when deleting the representation. + // There should be no side effects from deleting rep and we don + // not want to release a deleted mutex. + delete old; + } +} + template <class T> ACE_Future_Rep<T>::ACE_Future_Rep (void) : value_ (0), @@ -43,7 +100,6 @@ template <class T> ACE_Future_Rep<T>::~ACE_Future_Rep (void) { delete this->value_; - this->value_ = 0; } template <class T> int @@ -63,7 +119,7 @@ ACE_Future_Rep<T>::set (const T &r) // Double-checked locking pattern to avoid multiple allocations. if (this->value_ == 0) - ACE_NEW_RETURN (this->value_, T (r), -1); + ACE_NEW_RETURN (this->value_, T (r), -1); // Signal all the waiting threads. return this->value_ready_.broadcast (); @@ -74,7 +130,8 @@ ACE_Future_Rep<T>::set (const T &r) } template <class T> int -ACE_Future_Rep<T>::get (T &value, ACE_Time_Value *tv) +ACE_Future_Rep<T>::get (T &value, + ACE_Time_Value *tv) { // If the value is already produced, return it. if (this->value_ == 0) @@ -85,11 +142,10 @@ ACE_Future_Rep<T>::get (T &value, ACE_Time_Value *tv) // producer writes to it. while (this->value_ == 0) - { - // Perform a timed wait. - if (this->value_ready_.wait (tv) == -1) - return -1; - } + // Perform a timed wait. + if (this->value_ready_.wait (tv) == -1) + return -1; + // Destructor releases the lock. } @@ -109,82 +165,45 @@ ACE_Future_Rep<T>::operator T () // If the value is not yet defined we must block until the // producer writes to it. + // Wait ``forever.'' + while (this->value_ == 0) - { - // wait forever - if (this->value_ready_.wait () == -1) - // What to do in this case since we've got to indicate - // failure somehow? Exceptions would be nice, but they're - // not portable... - return 0; - } + if (this->value_ready_.wait () == -1) + // What to do in this case since we've got to indicate + // failure somehow? Exceptions would be nice, but they're + // not portable... + return 0; // Destructor releases the mutex - } return *this->value_; } - template <class T> ACE_Future<T>::ACE_Future (void) - : future_rep_ (0) + : future_rep_ (FUTURE_REP::create ()) { } template <class T> ACE_Future<T>::ACE_Future (const ACE_Future<T> &r) + : future_rep_ (FUTURE_REP::attach (((ACE_Future<T> &) r).future_rep_)) { - - // copy constructor: - // - // bind <this> to the same <ACE_Future_Rep> as <r>. - - // @@ not really clear if this is needed... after all this - // ACE_Future is just being instantiated... - ACE_MT (ACE_GUARD (ACE_Thread_Mutex, ace_mon, this->mutex_)); - - // acquire the mutex on <r>. We have to make sure - // that <r> does not delete its future_rep_... - - ACE_MT (ACE_GUARD (ACE_Thread_Mutex, r_mon, (ACE_Thread_Mutex &) r.mutex_)); - - // Check if 'r' has already a ACE_Future_rep bound to it. - if (r.future_rep_ == 0) - this->future_rep_ = r.create_rep_i (); - else - // ACE_Future_rep exists already, we can just link to it. - this->future_rep_ = r.future_rep_; - - this->future_rep_->ref_count_++; - } template <class T> ACE_Future<T>::ACE_Future (const T &r) + : future_rep_ (FUTURE_REP::create ()) { ACE_DEBUG ((LM_DEBUG," (%t) funny constructor\n")); - ACE_MT (ACE_GUARD (ACE_Thread_Mutex, ace_mon, this->mutex_)); - this->create_rep_i ()->set (r); + this->future_rep_->set (r); } template <class T> ACE_Future<T>::~ACE_Future (void) { - ACE_MT (ACE_GUARD (ACE_Thread_Mutex, ace_mon, this->mutex_)); - - if (this->future_rep_) - { - this->future_rep_->ref_count_--; - - if (this->future_rep_->ref_count_ == 0) - { - delete this->future_rep_; - this->future_rep_ = 0; - } - } - + FUTURE_REP::detach (future_rep_); } template <class T> int @@ -202,64 +221,35 @@ ACE_Future<T>::operator!= (const ACE_Future<T> &r) const template <class T> int ACE_Future<T>::cancel (const T &r) { - ACE_MT (ACE_GUARD_RETURN (ACE_Thread_Mutex, ace_mon, this->mutex_, -1)); + this->cancel (); + return this->future_rep_->set (r); +} +template <class T> int +ACE_Future<T>::cancel (void) +{ // If this ACE_Future is already attached to a ACE_Future_Rep, // detach it (maybe delete the ACE_Future_Rep). - if (this->future_rep_) - { - this->future_rep_->ref_count_--; - - if (this->future_rep_->ref_count_ == 0) - delete this->future_rep_; - } - - // Make a new ACE_Future_Rep and immediately assign - // the new value to it. - this->create_rep_i (); - return this->future_rep_->set (r); + FUTURE_REP::assign (this->future_rep_, FUTURE_REP::create ()); + return 0; } template <class T> int ACE_Future<T>::set (const T &r) { - if (this->future_rep_) - // Give the pointer to the result to the ACE_Future_Rep. - return this->future_rep_->set (r); - else - // @@ Maybe this should return a special value to indicate that - // there's no <ACE_Future_Rep> yet? - return 0; -} - -template <class T> ACE_Future_Rep<T> * -ACE_Future<T>::create_rep_i (void) const -{ - // Should only be called internally with locks held. - ACE_NEW_RETURN (((ACE_Future<T> *) this)->future_rep_, ACE_Future_Rep<T>, 0); - this->future_rep_->ref_count_ = 1; - return this->future_rep_; + // Give the pointer to the result to the ACE_Future_Rep. + return this->future_rep_->set (r); } - template <class T> int ACE_Future<T>::ready (void) { // We're ready if the ACE_Future_rep is ready... - if (this->future_rep_) - return this->future_rep_->ready (); - else - return 0; + return this->future_rep_->ready (); } template <class T> int ACE_Future<T>::get (T &value, ACE_Time_Value *tv) { - ACE_MT (ACE_GUARD_RETURN (ACE_Thread_Mutex, ace_mon, this->mutex_, -1)); - - if (this->future_rep_ == 0) - // Oops, we have to create a ACE_Future_Rep first. - this->create_rep_i (); - // We return the ACE_Future_rep. return this->future_rep_->get (value, tv); } @@ -283,38 +273,16 @@ ACE_Future<T>::operator T () } template <class T> void -ACE_Future<T>::operator = (const ACE_Future<T> &r) +ACE_Future<T>::operator = (const ACE_Future<T> &rhs) { // assignment: // // bind <this> to the same <ACE_Future_Rep> as <r>. - ACE_MT (ACE_GUARD (ACE_Thread_Mutex, ace_mon, this->mutex_)); - - // if there is already a <ACE_Future_Rep> we have - // to disconnect from it... - if (this->future_rep_) - { - // Disconnect from the <ACE_Future_Rep>. - this->future_rep_->ref_count_--; - - if (this->future_rep_->ref_count_ == 0) - delete this->future_rep_; - } - - // Acquire the mutex on <r>. We have to make sure - // that <r> does not delete it's future_rep_... - - ACE_MT (ACE_GUARD (ACE_Thread_Mutex, r_mon, (ACE_Thread_Mutex &) r.mutex_)); - - // Check if 'r' has already a ACE_Future_rep bound to it. - if (r.future_rep_ == 0) - this->future_rep_ = r.create_rep_i (); - else - // ACE_Future_rep exists already, we can just link to it. - this->future_rep_ = r.future_rep_; - - this->future_rep_->ref_count_++; + // This will work if &r == this, by first increasing the ref count + ACE_Future<T> &r = ( ACE_Future<T> &) rhs; + FUTURE_REP::assign (this->future_rep_, + FUTURE_REP::attach (r.future_rep_)); } template <class T> void @@ -324,8 +292,6 @@ ACE_Future<T>::dump (void) const if (this->future_rep_) this->future_rep_->dump (); - - this->mutex_.dump (); ACE_DEBUG ((LM_DEBUG, ACE_END_DUMP)); } @@ -346,6 +312,8 @@ ACE_Future<T>::operator &() } #if defined (ACE_TEMPLATES_REQUIRE_SPECIALIZATION) +// This should probably be moved elsewhere now that ACE_Atomic_Op<> +// isn't used. template class ACE_Atomic_Op<ACE_Thread_Mutex, int>; #endif /* ACE_TEMPLATES_REQUIRE_SPECIALIZATION */ |