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Diffstat (limited to '')
| -rw-r--r-- | src/xml/composite-node-observer.cpp | 237 |
1 files changed, 237 insertions, 0 deletions
diff --git a/src/xml/composite-node-observer.cpp b/src/xml/composite-node-observer.cpp new file mode 100644 index 0000000..541f289 --- /dev/null +++ b/src/xml/composite-node-observer.cpp @@ -0,0 +1,237 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/** @file + * TODO: insert short description here + *//* + * Authors: see git history + * + * Copyright (C) 2018 Authors + * Released under GNU GPL v2+, read the file 'COPYING' for more information. + */ +/* + * Inkscape::XML::CompositeNodeObserver - combine multiple observers + * + * Copyright 2005 MenTaLguY <mental@rydia.net> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * See the file COPYING for details. + * + */ + +#include <algorithm> +#include <cstring> +#include <glib.h> + +#include "xml/composite-node-observer.h" +#include "debug/event-tracker.h" +#include "debug/simple-event.h" + +namespace Inkscape { + +namespace XML { + +void CompositeNodeObserver::notifyChildAdded(Node &node, Node &child, Node *prev) +{ + _startIteration(); + for (auto & iter : _active) + { + if (!iter.marked) { + iter.observer->notifyChildAdded(node, child, prev); + } + } + _finishIteration(); +} + +void CompositeNodeObserver::notifyChildRemoved(Node &node, Node &child, + Node *prev) +{ + _startIteration(); + for (auto & iter : _active) + { + if (!iter.marked) { + iter.observer->notifyChildRemoved(node, child, prev); + } + } + _finishIteration(); +} + +void CompositeNodeObserver::notifyChildOrderChanged(Node &node, Node &child, + Node *old_prev, + Node *new_prev) +{ + _startIteration(); + for (auto & iter : _active) + { + if (!iter.marked) { + iter.observer->notifyChildOrderChanged(node, child, old_prev, new_prev); + } + } + _finishIteration(); +} + +void CompositeNodeObserver::notifyContentChanged( + Node &node, + Util::ptr_shared old_content, Util::ptr_shared new_content +) { + _startIteration(); + for (auto & iter : _active) + { + if (!iter.marked) { + iter.observer->notifyContentChanged(node, old_content, new_content); + } + } + _finishIteration(); +} + +void CompositeNodeObserver::notifyAttributeChanged( + Node &node, GQuark name, + Util::ptr_shared old_value, Util::ptr_shared new_value +) { + _startIteration(); + for (auto & iter : _active) + { + if (!iter.marked) { + iter.observer->notifyAttributeChanged(node, name, old_value, new_value); + } + } + _finishIteration(); +} + +void CompositeNodeObserver::notifyElementNameChanged(Node& node, GQuark old_name, GQuark new_name) +{ + _startIteration(); + for (auto& iter : _active) { + if (!iter.marked) { + iter.observer->notifyElementNameChanged(node, old_name, new_name); + } + } + _finishIteration(); +} + +void CompositeNodeObserver::add(NodeObserver &observer) { + if (_iterating) { + _pending.emplace_back(&observer); + } else { + _active.emplace_back(&observer); + } +} + +namespace { + +typedef CompositeNodeObserver::ObserverRecord ObserverRecord; +typedef CompositeNodeObserver::ObserverRecordList ObserverRecordList; + +template <typename ObserverPredicate> +struct unmarked_record_satisfying { + ObserverPredicate predicate; + unmarked_record_satisfying(ObserverPredicate p) : predicate(p) {} + bool operator()(ObserverRecord const &record) { + return !record.marked && predicate(record.observer); + } +}; + +template <typename Predicate> +bool mark_one(ObserverRecordList &observers, unsigned &marked_count, + Predicate p) +{ + auto found = std::find_if( + observers.begin(), observers.end(), + unmarked_record_satisfying<Predicate>(p) + ); + + if ( found != observers.end() ) { + ++marked_count; + found->marked = true; + return true; + } else { + return false; + } +} + +template <typename Predicate> +bool remove_one(ObserverRecordList &observers, unsigned &/*marked_count*/, + Predicate p) +{ + auto found = std::find_if( + observers.begin(), observers.end(), + unmarked_record_satisfying<Predicate>(p) + ); + + if ( found != observers.end() ) { + // for O(1) removal + if (observers.size() > 3) { + *found = std::move(observers.back()); + observers.pop_back(); + } else { + observers.erase(found); + } + return true; + } else { + return false; + } +} + +bool is_marked(ObserverRecord const &record) { return record.marked; } + +void remove_all_marked(ObserverRecordList &observers, unsigned &marked_count) +{ + if (marked_count) { + g_assert(!observers.empty()); + + auto newEnd = std::remove_if(observers.begin(), observers.end(), is_marked); + observers.erase(newEnd, observers.end()); + marked_count = 0; + } +} + +} + +void CompositeNodeObserver::_finishIteration() { + if (!--_iterating) { + remove_all_marked(_active, _active_marked); + remove_all_marked(_pending, _pending_marked); + _active.insert(_active.end(), _pending.begin(), _pending.end()); + _pending.clear(); + + g_assert(_pending.empty()); + } +} + +namespace { + +struct eql_observer { + NodeObserver const *observer; + eql_observer(NodeObserver const *o) : observer(o) {} + bool operator()(NodeObserver const *other) { + return observer == other; + } +}; + +} + +void CompositeNodeObserver::remove(NodeObserver &observer) { + eql_observer p(&observer); + if (_iterating) { + mark_one(_active, _active_marked, p) || + mark_one(_pending, _pending_marked, p); + } else { + remove_one(_active, _active_marked, p) || + remove_one(_pending, _pending_marked, p); + } +} + +} // namespace XML +} // namespace Inkscape +/* + Local Variables: + mode:c++ + c-file-style:"stroustrup" + c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +)) + indent-tabs-mode:nil + fill-column:99 + End: +*/ +// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:fileencoding=utf-8:textwidth=99 : |