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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 16:51:28 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 16:51:28 +0000
commit940b4d1848e8c70ab7642901a68594e8016caffc (patch)
treeeb72f344ee6c3d9b80a7ecc079ea79e9fba8676d /svl/source/notify
parentInitial commit. (diff)
downloadlibreoffice-upstream.tar.xz
libreoffice-upstream.zip
Adding upstream version 1:7.0.4.upstream/1%7.0.4upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r--svl/source/notify/SfxBroadcaster.cxx178
-rw-r--r--svl/source/notify/broadcast.cxx267
-rw-r--r--svl/source/notify/hint.cxx31
-rw-r--r--svl/source/notify/isethint.cxx38
-rw-r--r--svl/source/notify/listener.cxx108
-rw-r--r--svl/source/notify/lstner.cxx173
6 files changed, 795 insertions, 0 deletions
diff --git a/svl/source/notify/SfxBroadcaster.cxx b/svl/source/notify/SfxBroadcaster.cxx
new file mode 100644
index 000000000..2e312a80c
--- /dev/null
+++ b/svl/source/notify/SfxBroadcaster.cxx
@@ -0,0 +1,178 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed
+ * with this work for additional information regarding copyright
+ * ownership. The ASF licenses this file to you under the Apache
+ * License, Version 2.0 (the "License"); you may not use this file
+ * except in compliance with the License. You may obtain a copy of
+ * the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <svl/SfxBroadcaster.hxx>
+
+#include <svl/hint.hxx>
+#include <svl/lstner.hxx>
+#include <tools/debug.hxx>
+
+#include <algorithm>
+#include <cassert>
+#include <vector>
+
+
+typedef std::vector<SfxListener*> SfxListenerArr_Impl;
+
+struct SfxBroadcaster::Impl
+{
+ /** Contains the positions of removed listeners. */
+ std::vector<size_t> m_RemovedPositions;
+ SfxListenerArr_Impl m_Listeners;
+};
+
+// broadcast immediately
+
+void SfxBroadcaster::Broadcast( const SfxHint &rHint )
+{
+ // notify all registered listeners exactly once
+ for (size_t i = 0; i < mpImpl->m_Listeners.size(); ++i)
+ {
+ SfxListener *const pListener = mpImpl->m_Listeners[i];
+ if (pListener)
+ pListener->Notify( *this, rHint );
+ }
+}
+
+// unregister all listeners
+
+SfxBroadcaster::~SfxBroadcaster() COVERITY_NOEXCEPT_FALSE
+{
+ Broadcast( SfxHint(SfxHintId::Dying) );
+
+ // remove all still registered listeners
+ for (size_t i = 0; i < mpImpl->m_Listeners.size(); ++i)
+ {
+ SfxListener *const pListener = mpImpl->m_Listeners[i];
+ if (pListener)
+ pListener->RemoveBroadcaster_Impl(*this);
+ }
+}
+
+
+// simple ctor of class SfxBroadcaster
+
+SfxBroadcaster::SfxBroadcaster() : mpImpl(new Impl)
+{
+}
+
+
+// copy ctor of class SfxBroadcaster
+
+
+SfxBroadcaster::SfxBroadcaster( const SfxBroadcaster &rBC ) : mpImpl(new Impl)
+{
+ for (size_t i = 0; i < rBC.mpImpl->m_Listeners.size(); ++i)
+ {
+ SfxListener *const pListener = rBC.mpImpl->m_Listeners[i];
+ if (pListener)
+ pListener->StartListening( *this );
+ }
+}
+
+
+// add a new SfxListener to the list
+
+void SfxBroadcaster::AddListener( SfxListener& rListener )
+{
+ DBG_TESTSOLARMUTEX();
+ if (mpImpl->m_RemovedPositions.empty())
+ {
+ mpImpl->m_Listeners.push_back(&rListener);
+ }
+ else
+ {
+ size_t targetPosition = mpImpl->m_RemovedPositions.back();
+ mpImpl->m_RemovedPositions.pop_back();
+ assert(mpImpl->m_Listeners[targetPosition] == nullptr);
+ mpImpl->m_Listeners[targetPosition] = &rListener;
+ }
+}
+
+
+// forward a notification to all registered listeners
+
+void SfxBroadcaster::Forward(SfxBroadcaster& rBC, const SfxHint& rHint)
+{
+ for (size_t i = 0; i < mpImpl->m_Listeners.size(); ++i)
+ {
+ SfxListener *const pListener = mpImpl->m_Listeners[i];
+ if (pListener)
+ pListener->Notify( rBC, rHint );
+ }
+}
+
+
+// remove one SfxListener from the list
+
+void SfxBroadcaster::RemoveListener( SfxListener& rListener )
+{
+ DBG_TESTSOLARMUTEX();
+
+ // First, check the slots either side of the last removed slot, makes a significant
+ // difference when the list is large.
+ int positionOfRemovedElement = -1;
+ if (!mpImpl->m_RemovedPositions.empty())
+ {
+ auto i = mpImpl->m_RemovedPositions.back();
+ if (i < mpImpl->m_Listeners.size() - 2 && mpImpl->m_Listeners[i+1] == &rListener)
+ {
+ positionOfRemovedElement = i + 1;
+ }
+ else if (i > 0 && mpImpl->m_Listeners[i-1] == &rListener)
+ {
+ positionOfRemovedElement = i-1;
+ }
+ }
+ // then scan the whole list if we didn't find it
+ if (positionOfRemovedElement == -1)
+ {
+ SfxListenerArr_Impl::iterator aIter = std::find(
+ mpImpl->m_Listeners.begin(), mpImpl->m_Listeners.end(), &rListener);
+ positionOfRemovedElement = std::distance(mpImpl->m_Listeners.begin(), aIter);
+ }
+ // DO NOT erase the listener, set the pointer to 0
+ // because the current continuation may contain this->Broadcast
+ mpImpl->m_Listeners[positionOfRemovedElement] = nullptr;
+ mpImpl->m_RemovedPositions.push_back(positionOfRemovedElement);
+}
+
+bool SfxBroadcaster::HasListeners() const
+{
+ return (GetListenerCount() != 0);
+}
+
+size_t SfxBroadcaster::GetListenerCount() const
+{
+ assert(mpImpl->m_Listeners.size() >= mpImpl->m_RemovedPositions.size());
+ return mpImpl->m_Listeners.size() - mpImpl->m_RemovedPositions.size();
+}
+
+size_t SfxBroadcaster::GetSizeOfVector() const
+{
+ return mpImpl->m_Listeners.size();
+}
+
+SfxListener* SfxBroadcaster::GetListener( size_t nNo ) const
+{
+ return mpImpl->m_Listeners[nNo];
+}
+
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/svl/source/notify/broadcast.cxx b/svl/source/notify/broadcast.cxx
new file mode 100644
index 000000000..586a09600
--- /dev/null
+++ b/svl/source/notify/broadcast.cxx
@@ -0,0 +1,267 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed
+ * with this work for additional information regarding copyright
+ * ownership. The ASF licenses this file to you under the Apache
+ * License, Version 2.0 (the "License"); you may not use this file
+ * except in compliance with the License. You may obtain a copy of
+ * the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <svl/broadcast.hxx>
+#include <svl/listener.hxx>
+#include <svl/hint.hxx>
+#include <o3tl/safeint.hxx>
+#include <cassert>
+#include <algorithm>
+
+/**
+ Design Notes
+ -------------------------------
+
+ This class is extremely heavily used - we can have millions of broadcasters and listeners and we can also
+ have a broadcaster that has a million listeners.
+
+ So we do a number of things
+ (*) use a cache-dense listener list (std::vector) because caching effects dominate a lot of operations
+ (*) use a sorted list to speed up find operations
+ (*) only sort the list when we absolutely have to, to speed up sequential add/remove operations
+ (*) defer removing items from the list by (ab)using the last bit of the pointer
+
+ Also we have some complications around destruction because
+ (*) we broadcast a message to indicate that we are destructing
+ (*) which can trigger arbitrality complicated behaviour, including
+ (*) adding a removing things from the in-destruction object!
+
+*/
+
+static bool isDeletedPtr(SvtListener* p)
+{
+ /** mark deleted entries by toggling the last bit,which is effectively unused, since the struct we point
+ * to is at least 16-bit aligned. This allows the binary seach to continue working even when we have
+ * deleted entries */
+#if SAL_TYPES_SIZEOFPOINTER == 4
+ return (reinterpret_cast<sal_uInt32>(p) & 0x01) == 0x01;
+#else
+ return (reinterpret_cast<sal_uInt64>(p) & 0x01) == 0x01;
+#endif
+}
+
+static void markDeletedPtr(SvtListener*& rp)
+{
+#if SAL_TYPES_SIZEOFPOINTER == 4
+ reinterpret_cast<sal_uInt32&>(rp) |= 0x01;
+#else
+ reinterpret_cast<sal_uInt64&>(rp) |= 0x01;
+#endif
+}
+
+static void sortListeners(std::vector<SvtListener*>& listeners, size_t firstUnsorted)
+{
+ // Add() only appends new values, so often the container will be sorted expect for one
+ // or few last items. For larger containers it is much more efficient to just handle
+ // the unsorted part.
+ auto sortedEnd = firstUnsorted == 0
+ ? std::is_sorted_until(listeners.begin(),listeners.end())
+ : listeners.begin() + firstUnsorted;
+ if( listeners.end() - sortedEnd == 1 )
+ { // Just one item, insert it in the right place.
+ SvtListener* item = listeners.back();
+ listeners.pop_back();
+ listeners.insert( std::upper_bound( listeners.begin(), listeners.end(), item ), item );
+ }
+ else if( o3tl::make_unsigned( sortedEnd - listeners.begin()) > listeners.size() * 3 / 4 )
+ { // Sort the unsorted part and then merge.
+ std::sort( sortedEnd, listeners.end());
+ std::inplace_merge( listeners.begin(), sortedEnd, listeners.end());
+ }
+ else
+ {
+ std::sort(listeners.begin(), listeners.end());
+ }
+}
+
+void SvtBroadcaster::Normalize() const
+{
+ // clear empty slots first, because then we often have to do very little sorting
+ if (mnEmptySlots)
+ {
+ maListeners.erase(
+ std::remove_if(maListeners.begin(), maListeners.end(), [] (SvtListener* p) { return isDeletedPtr(p); }),
+ maListeners.end());
+ mnEmptySlots = 0;
+ }
+
+ if (mnListenersFirstUnsorted != static_cast<sal_Int32>(maListeners.size()))
+ {
+ sortListeners(maListeners, mnListenersFirstUnsorted);
+ mnListenersFirstUnsorted = maListeners.size();
+ }
+
+ if (!mbDestNormalized)
+ {
+ sortListeners(maDestructedListeners, 0);
+ mbDestNormalized = true;
+ }
+}
+
+void SvtBroadcaster::Add( SvtListener* p )
+{
+ assert(!mbDisposing && "called inside my own destructor?");
+ assert(!mbAboutToDie && "called after PrepareForDestruction()?");
+ if (mbDisposing || mbAboutToDie)
+ return;
+ // Avoid normalizing if the item appended keeps the container sorted.
+ auto nRealSize = static_cast<sal_Int32>(maListeners.size() - mnEmptySlots);
+ auto bSorted = mnListenersFirstUnsorted == nRealSize;
+ if (maListeners.empty() || (bSorted && maListeners.back() <= p))
+ {
+ ++mnListenersFirstUnsorted;
+ maListeners.push_back(p);
+ return;
+ }
+ // see if we can stuff it into an empty slot, which succeeds surprisingly often in
+ // some calc workloads where it removes and then re-adds the same listener
+ if (mnEmptySlots && bSorted)
+ {
+ auto it = std::lower_bound(maListeners.begin(), maListeners.end(), p);
+ if (it != maListeners.end() && isDeletedPtr(*it))
+ {
+ *it = p;
+ ++mnListenersFirstUnsorted;
+ --mnEmptySlots;
+ return;
+ }
+ }
+ maListeners.push_back(p);
+}
+
+void SvtBroadcaster::Remove( SvtListener* p )
+{
+ if (mbDisposing)
+ return;
+
+ if (mbAboutToDie)
+ {
+ // only reset mbDestNormalized if we are going to become unsorted
+ if (!maDestructedListeners.empty() && maDestructedListeners.back() > p)
+ mbDestNormalized = false;
+ maDestructedListeners.push_back(p);
+ return;
+ }
+
+ // We only need to fully normalize if one or more Add()s have been performed that make the array unsorted.
+ auto nRealSize = static_cast<sal_Int32>(maListeners.size() - mnEmptySlots);
+ if (mnListenersFirstUnsorted != nRealSize || (maListeners.size() > 1024 && maListeners.size() / nRealSize > 16))
+ Normalize();
+
+ auto it = std::lower_bound(maListeners.begin(), maListeners.end(), p);
+ assert (it != maListeners.end() && *it == p);
+ if (it != maListeners.end() && *it == p)
+ {
+ markDeletedPtr(*it);
+ ++mnEmptySlots;
+ --mnListenersFirstUnsorted;
+ }
+
+ if (maListeners.size() - mnEmptySlots == 0)
+ ListenersGone();
+}
+
+SvtBroadcaster::SvtBroadcaster()
+ : mnEmptySlots(0)
+ , mnListenersFirstUnsorted(0)
+ , mbAboutToDie(false)
+ , mbDisposing(false)
+ , mbDestNormalized(true)
+{}
+
+SvtBroadcaster::SvtBroadcaster( const SvtBroadcaster &rBC ) :
+ mnEmptySlots(0), mnListenersFirstUnsorted(0),
+ mbAboutToDie(false), mbDisposing(false),
+ mbDestNormalized(true)
+{
+ assert(!rBC.mbAboutToDie && "copying an object marked with PrepareForDestruction()?");
+ assert(!rBC.mbDisposing && "copying an object that is in its destructor?");
+
+ rBC.Normalize(); // so that insert into ourself is in-order, and therefore we do not need to Normalize()
+ maListeners.reserve(rBC.maListeners.size());
+ for (SvtListener* p : rBC.maListeners)
+ p->StartListening(*this); // this will call back into this->Add()
+}
+
+SvtBroadcaster::~SvtBroadcaster()
+{
+ mbDisposing = true;
+ Broadcast( SfxHint(SfxHintId::Dying) );
+
+ Normalize();
+
+ // now when both lists are sorted, we can linearly unregister all
+ // listeners, with the exception of those that already asked to be removed
+ // during their own destruction
+ ListenersType::const_iterator dest(maDestructedListeners.begin());
+ for (auto& rpListener : maListeners)
+ {
+ // skip the destructed ones
+ while (dest != maDestructedListeners.end() && (*dest < rpListener))
+ ++dest;
+
+ if (dest == maDestructedListeners.end() || *dest != rpListener)
+ rpListener->BroadcasterDying(*this);
+ }
+}
+
+void SvtBroadcaster::Broadcast( const SfxHint &rHint )
+{
+ Normalize();
+
+ ListenersType::const_iterator dest(maDestructedListeners.begin());
+ ListenersType aListeners(maListeners); // this copy is important to avoid erasing entries while iterating
+ for (auto& rpListener : aListeners)
+ {
+ // skip the destructed ones
+ while (dest != maDestructedListeners.end() && (*dest < rpListener))
+ ++dest;
+
+ if (dest == maDestructedListeners.end() || *dest != rpListener)
+ rpListener->Notify(rHint);
+ }
+}
+
+void SvtBroadcaster::ListenersGone() {}
+
+SvtBroadcaster::ListenersType& SvtBroadcaster::GetAllListeners()
+{
+ Normalize();
+ return maListeners;
+}
+
+const SvtBroadcaster::ListenersType& SvtBroadcaster::GetAllListeners() const
+{
+ Normalize();
+ return maListeners;
+}
+
+bool SvtBroadcaster::HasListeners() const
+{
+ return (maListeners.size() - mnEmptySlots) > 0;
+}
+
+void SvtBroadcaster::PrepareForDestruction()
+{
+ mbAboutToDie = true;
+ // the reserve() serves two purpose (1) performance (2) makes sure our iterators do not become invalid
+ maDestructedListeners.reserve(maListeners.size());
+}
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/svl/source/notify/hint.cxx b/svl/source/notify/hint.cxx
new file mode 100644
index 000000000..ad36d5098
--- /dev/null
+++ b/svl/source/notify/hint.cxx
@@ -0,0 +1,31 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed
+ * with this work for additional information regarding copyright
+ * ownership. The ASF licenses this file to you under the Apache
+ * License, Version 2.0 (the "License"); you may not use this file
+ * except in compliance with the License. You may obtain a copy of
+ * the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+
+#include <svl/hint.hxx>
+
+
+// virtual dtor for the typical base-class Hint
+
+SfxHint::~SfxHint() COVERITY_NOEXCEPT_FALSE
+{
+}
+
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/svl/source/notify/isethint.cxx b/svl/source/notify/isethint.cxx
new file mode 100644
index 000000000..6f810240a
--- /dev/null
+++ b/svl/source/notify/isethint.cxx
@@ -0,0 +1,38 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed
+ * with this work for additional information regarding copyright
+ * ownership. The ASF licenses this file to you under the Apache
+ * License, Version 2.0 (the "License"); you may not use this file
+ * except in compliance with the License. You may obtain a copy of
+ * the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+
+#include <svl/isethint.hxx>
+#include <svl/itemset.hxx>
+
+
+/**
+ * Copies the SfxItemSet passed as a parameter.
+ */
+SfxItemSetHint::SfxItemSetHint( const SfxItemSet &rItemSet )
+: _pItemSet( rItemSet.Clone() )
+{
+}
+
+SfxItemSetHint::~SfxItemSetHint()
+{
+}
+
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/svl/source/notify/listener.cxx b/svl/source/notify/listener.cxx
new file mode 100644
index 000000000..51564ce9b
--- /dev/null
+++ b/svl/source/notify/listener.cxx
@@ -0,0 +1,108 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed
+ * with this work for additional information regarding copyright
+ * ownership. The ASF licenses this file to you under the Apache
+ * License, Version 2.0 (the "License"); you may not use this file
+ * except in compliance with the License. You may obtain a copy of
+ * the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <svl/listener.hxx>
+#include <svl/broadcast.hxx>
+
+SvtListener::QueryBase::QueryBase( sal_uInt16 nId ) : mnId(nId) {}
+SvtListener::QueryBase::~QueryBase() {}
+
+sal_uInt16 SvtListener::QueryBase::getId() const
+{
+ return mnId;
+}
+
+SvtListener::SvtListener() {}
+
+SvtListener::SvtListener( const SvtListener & ) {}
+
+SvtListener::~SvtListener() COVERITY_NOEXCEPT_FALSE
+{
+ // Unregister itself from all broadcasters it's listening to.
+ EndListeningAll();
+}
+
+// registers at a specific SvtBroadcaster
+
+bool SvtListener::StartListening( SvtBroadcaster& rBroadcaster )
+{
+ std::pair<BroadcastersType::const_iterator, bool> r =
+ maBroadcasters.insert(&rBroadcaster);
+ if (r.second)
+ {
+ // This is a new broadcaster.
+ rBroadcaster.Add(this);
+ }
+ return r.second;
+}
+
+bool SvtListener::EndListening( SvtBroadcaster& rBroadcaster )
+{
+ BroadcastersType::const_iterator it = maBroadcasters.find(&rBroadcaster);
+ if (it == maBroadcasters.end())
+ // Not listening to this broadcaster.
+ return false;
+
+ rBroadcaster.Remove(this);
+ maBroadcasters.erase(it);
+ return true;
+}
+
+// called from the SvtBroadcaster destructor, used to avoid calling
+// back into the broadcaster again
+void SvtListener::BroadcasterDying( SvtBroadcaster& rBroadcaster )
+{
+ BroadcastersType::const_iterator it = maBroadcasters.find(&rBroadcaster);
+ if (it != maBroadcasters.end())
+ maBroadcasters.erase(it);
+}
+
+void SvtListener::EndListeningAll()
+{
+ for (SvtBroadcaster* p : maBroadcasters)
+ {
+ SvtBroadcaster& rBC = *p;
+ rBC.Remove(this);
+ }
+ maBroadcasters.clear();
+}
+
+
+void SvtListener::CopyAllBroadcasters( const SvtListener& r )
+{
+ EndListeningAll();
+ BroadcastersType aCopy(r.maBroadcasters);
+ maBroadcasters.swap(aCopy);
+ for (SvtBroadcaster* p : maBroadcasters)
+ {
+ p->Add(this);
+ }
+}
+
+bool SvtListener::HasBroadcaster() const
+{
+ return !maBroadcasters.empty();
+}
+
+void SvtListener::Notify( const SfxHint& /*rHint*/ ) {}
+
+void SvtListener::Query( QueryBase& /*rQuery*/ ) const {}
+
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/svl/source/notify/lstner.cxx b/svl/source/notify/lstner.cxx
new file mode 100644
index 000000000..fe6f2b8af
--- /dev/null
+++ b/svl/source/notify/lstner.cxx
@@ -0,0 +1,173 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed
+ * with this work for additional information regarding copyright
+ * ownership. The ASF licenses this file to you under the Apache
+ * License, Version 2.0 (the "License"); you may not use this file
+ * except in compliance with the License. You may obtain a copy of
+ * the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <svl/lstner.hxx>
+
+#include <svl/SfxBroadcaster.hxx>
+#include <sal/backtrace.hxx>
+#include <sal/log.hxx>
+
+#include <algorithm>
+#include <cassert>
+#include <vector>
+#include <memory>
+#include <map>
+
+struct SfxListener::Impl
+{
+ std::vector<SfxBroadcaster*> maBCs;
+#ifdef DBG_UTIL
+ std::map<SfxBroadcaster*, std::unique_ptr<sal::BacktraceState>>
+ maCallStacks;
+#endif
+};
+
+// simple ctor of class SfxListener
+
+SfxListener::SfxListener() : mpImpl(new Impl)
+{
+}
+
+// copy ctor of class SfxListener
+
+SfxListener::SfxListener( const SfxListener &rListener ) : mpImpl(new Impl)
+{
+ for ( size_t n = 0; n < rListener.mpImpl->maBCs.size(); ++n )
+ StartListening( *rListener.mpImpl->maBCs[n] );
+}
+
+// unregisters the SfxListener from its SfxBroadcasters
+
+SfxListener::~SfxListener() COVERITY_NOEXCEPT_FALSE
+{
+ // unregister at all remaining broadcasters
+ for ( size_t nPos = 0; nPos < mpImpl->maBCs.size(); ++nPos )
+ {
+ SfxBroadcaster *pBC = mpImpl->maBCs[nPos];
+ pBC->RemoveListener(*this);
+ }
+}
+
+
+// unregisters a specific SfxBroadcaster
+
+void SfxListener::RemoveBroadcaster_Impl( SfxBroadcaster& rBroadcaster )
+{
+ auto it = std::find( mpImpl->maBCs.begin(), mpImpl->maBCs.end(), &rBroadcaster );
+ if (it != mpImpl->maBCs.end()) {
+ mpImpl->maBCs.erase( it );
+#ifdef DBG_UTIL
+ mpImpl->maCallStacks.erase( &rBroadcaster );
+#endif
+ }
+}
+
+
+
+/**
+ Registers a specific SfxBroadcaster.
+
+ Some code uses duplicates as a kind of ref-counting thing i.e. they add and remove listeners
+ on different code paths, and they only really stop listening when the last EndListening() is called.
+*/
+void SfxListener::StartListening(SfxBroadcaster& rBroadcaster, DuplicateHandling eDuplicateHanding)
+{
+ bool bListeningAlready = IsListening( rBroadcaster );
+
+#ifdef DBG_UTIL
+ if (bListeningAlready && eDuplicateHanding == DuplicateHandling::Unexpected)
+ {
+ auto f = mpImpl->maCallStacks.find( &rBroadcaster );
+ SAL_WARN("svl", "previous StartListening call came from: " << sal::backtrace_to_string(f->second.get()));
+ }
+#endif
+ assert(!(bListeningAlready && eDuplicateHanding == DuplicateHandling::Unexpected) && "duplicate listener, try building with DBG_UTIL to find the other insert site.");
+
+ if (!bListeningAlready || eDuplicateHanding != DuplicateHandling::Prevent)
+ {
+ rBroadcaster.AddListener(*this);
+ mpImpl->maBCs.push_back( &rBroadcaster );
+#ifdef DBG_UTIL
+ mpImpl->maCallStacks.emplace( &rBroadcaster, sal::backtrace_get(10) );
+#endif
+ assert(IsListening(rBroadcaster) && "StartListening failed");
+ }
+}
+
+// unregisters a specific SfxBroadcaster
+
+void SfxListener::EndListening( SfxBroadcaster& rBroadcaster, bool bRemoveAllDuplicates )
+{
+ auto beginIt = mpImpl->maBCs.begin();
+ do
+ {
+ auto it = std::find( beginIt, mpImpl->maBCs.end(), &rBroadcaster );
+ if ( it == mpImpl->maBCs.end() )
+ {
+ break;
+ }
+ rBroadcaster.RemoveListener(*this);
+ beginIt = mpImpl->maBCs.erase( it );
+#ifdef DBG_UTIL
+ mpImpl->maCallStacks.erase( &rBroadcaster );
+#endif
+ }
+ while ( bRemoveAllDuplicates );
+}
+
+
+// unregisters all Broadcasters
+
+void SfxListener::EndListeningAll()
+{
+ std::vector<SfxBroadcaster*> aBroadcasters;
+ std::swap(mpImpl->maBCs, aBroadcasters);
+ for (SfxBroadcaster *pBC : aBroadcasters)
+ pBC->RemoveListener(*this);
+#ifdef DBG_UTIL
+ mpImpl->maCallStacks.clear();
+#endif
+}
+
+
+bool SfxListener::IsListening( SfxBroadcaster& rBroadcaster ) const
+{
+ return mpImpl->maBCs.end() != std::find( mpImpl->maBCs.begin(), mpImpl->maBCs.end(), &rBroadcaster );
+}
+
+sal_uInt16 SfxListener::GetBroadcasterCount() const
+{
+ return mpImpl->maBCs.size();
+}
+
+SfxBroadcaster* SfxListener::GetBroadcasterJOE( sal_uInt16 nNo ) const
+{
+ return mpImpl->maBCs[nNo];
+}
+
+
+// base implementation of notification handler
+
+void SfxListener::Notify( SfxBroadcaster& rBroadcaster, const SfxHint& )
+{
+ (void) rBroadcaster;
+ assert(IsListening(rBroadcaster));
+}
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */