/*
* Copyright 2003, The libsigc++ Development Team
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <sigc++/signal_base.h>
#include <memory> // std::unique_ptr
namespace sigc {
namespace internal {
// Data sent from signal_impl::insert() to slot_rep::set_parent() when a slot is
// connected, and then sent from slot_rep::disconnect() to signal_impl::notify()
// when the slot is disconnected. Bug 167714.
struct self_and_iter
{
signal_impl* self_;
signal_impl::iterator_type iter_;
self_and_iter(signal_impl* self, signal_impl::iterator_type iter)
: self_(self), iter_(iter) {}
};
signal_impl::signal_impl()
: ref_count_(0), exec_count_(0), deferred_(false)
{}
// only MSVC needs this to guarantee that all new/delete are executed from the DLL module
#ifdef SIGC_NEW_DELETE_IN_LIBRARY_ONLY
void* signal_impl::operator new(size_t size_)
{
return malloc(size_);
}
void signal_impl::operator delete(void* p)
{
free(p);
}
#endif
void signal_impl::clear()
{
// Don't let signal_impl::notify() erase the slots. It would invalidate the
// iterator in the following loop.
const bool saved_deferred = deferred_;
signal_exec exec(this);
// Disconnect all connected slots before they are deleted.
// signal_impl::notify() will be called and delete the self_and_iter structs.
for (auto& slot : slots_)
slot.disconnect();
deferred_ = saved_deferred;
slots_.clear();
}
signal_impl::size_type signal_impl::size() const noexcept
{
return slots_.size();
}
bool signal_impl::blocked() const noexcept
{
for (const auto& slot : const_cast<const std::list<slot_base>&>(slots_))
{
if (!slot.blocked())
return false;
}
return true;
}
void signal_impl::block(bool should_block) noexcept
{
for (auto& slot : slots_)
{
slot.block(should_block);
}
}
signal_impl::iterator_type signal_impl::connect(const slot_base& slot_)
{
return insert(slots_.end(), slot_);
}
signal_impl::iterator_type signal_impl::connect(slot_base&& slot_)
{
return insert(slots_.end(), std::move(slot_));
}
signal_impl::iterator_type signal_impl::erase(iterator_type i)
{
// Don't let signal_impl::notify() erase the slot. It would be more
// difficult to get the correct return value from signal_impl::erase().
const bool saved_deferred = deferred_;
signal_exec exec(this);
// Disconnect the slot before it is deleted.
// signal_impl::notify() will be called and delete the self_and_iter struct.
i->disconnect();
deferred_ = saved_deferred;
return slots_.erase(i);
}
signal_impl::iterator_type signal_impl::insert(signal_impl::iterator_type i, const slot_base& slot_)
{
auto temp = slots_.insert(i, slot_);
auto si = new self_and_iter(this, temp);
temp->set_parent(si, ¬ify);
return temp;
}
signal_impl::iterator_type signal_impl::insert(signal_impl::iterator_type i, slot_base&& slot_)
{
auto temp = slots_.insert(i, std::move(slot_));
auto si = new self_and_iter(this, temp);
temp->set_parent(si, ¬ify);
return temp;
}
void signal_impl::sweep()
{
// The deletion of a slot may cause the deletion of a signal_base,
// a decrementation of ref_count_, and the deletion of this.
// In that case, the deletion of this is deferred to ~signal_exec().
signal_exec exec(this);
deferred_ = false;
auto i = slots_.begin();
while (i != slots_.end())
if ((*i).empty())
i = slots_.erase(i);
else
++i;
}
//static
void* signal_impl::notify(void* d)
{
std::unique_ptr<self_and_iter> si(static_cast<self_and_iter*>(d));
if (si->self_->exec_count_ == 0)
{
// The deletion of a slot may cause the deletion of a signal_base,
// a decrementation of si->self_->ref_count_, and the deletion of si->self_.
// In that case, the deletion of si->self_ is deferred to ~signal_exec().
signal_exec exec(si->self_);
si->self_->slots_.erase(si->iter_);
}
else // This is occuring during signal emission or slot erasure.
si->self_->deferred_ = true; // => sweep() will be called from ~signal_exec() after signal emission.
return nullptr; // This is safer because we don't have to care about our
// iterators in emit(), clear(), and erase().
}
} /* namespace internal */
signal_base::signal_base() noexcept
: impl_(nullptr)
{}
signal_base::signal_base(const signal_base& src) noexcept
: trackable(),
impl_(src.impl())
{
impl_->reference();
}
signal_base::signal_base(signal_base&& src)
: trackable(std::move(src)),
impl_(std::move(src.impl_))
{
src.impl_ = nullptr;
}
signal_base::~signal_base()
{
if (impl_)
{
// Disconnect all slots before impl_ is deleted.
// TODO: Move the signal_impl::clear() call to ~signal_impl() when ABI can be broken.
if (impl_->ref_count_ == 1)
impl_->clear();
impl_->unreference();
}
}
void signal_base::clear()
{
if (impl_)
impl_->clear();
}
signal_base::size_type signal_base::size() const noexcept
{
return (impl_ ? impl_->size() : 0);
}
bool signal_base::blocked() const noexcept
{
return (impl_ ? impl_->blocked() : true);
}
void signal_base::block(bool should_block) noexcept
{
if (impl_)
impl_->block(should_block);
}
void signal_base::unblock() noexcept
{
if (impl_)
impl_->block(false);
}
signal_base::iterator_type signal_base::connect(const slot_base& slot_)
{
return impl()->connect(slot_);
}
signal_base::iterator_type signal_base::connect(slot_base&& slot_)
{
return impl()->connect(std::move(slot_));
}
signal_base::iterator_type signal_base::insert(iterator_type i, const slot_base& slot_)
{
return impl()->insert(i, slot_);
}
signal_base::iterator_type signal_base::insert(iterator_type i, slot_base&& slot_)
{
return impl()->insert(i, std::move(slot_));
}
signal_base::iterator_type signal_base::erase(iterator_type i)
{
return impl()->erase(i);
}
signal_base& signal_base::operator=(const signal_base& src)
{
if (src.impl_ == impl_) return *this;
if (impl_)
{
// Disconnect all slots before impl_ is deleted.
// TODO: Move the signal_impl::clear() call to ~signal_impl() when ABI can be broken.
if (impl_->ref_count_ == 1)
impl_->clear();
impl_->unreference();
}
impl_ = src.impl();
impl_->reference();
return *this;
}
signal_base& signal_base::operator=(signal_base&& src)
{
if (src.impl_ == impl_) return *this;
if (impl_)
{
// Disconnect all slots before impl_ is deleted.
// TODO: Move the signal_impl::clear() call to ~signal_impl() when ABI can be broken.
if (impl_->ref_count_ == 1)
impl_->clear();
impl_->unreference();
}
src.notify_callbacks();
impl_ = src.impl_;
src.impl_ = nullptr;
return *this;
}
internal::signal_impl* signal_base::impl() const
{
if (!impl_) {
impl_ = new internal::signal_impl;
impl_->reference(); // start with a reference count of 1
}
return impl_;
}
} /* sigc */