Adding upstream version 1.2.2.upstream/1.2.2upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

19 files changed, 1658 insertions, 0 deletions

diff --git a/src/debug/CMakeLists.txt b/src/debug/CMakeLists.txt
new file mode 100644
index 0000000..954df1f
--- /dev/null
+++ b/src/debug/CMakeLists.txt
@@ -0,0 +1,29 @@
+# SPDX-License-Identifier: GPL-2.0-or-later
+
+set(debug_SRC
+	demangle.cpp
+	heap.cpp
+	log-display-config.cpp
+	logger.cpp
+	sysv-heap.cpp
+	timestamp.cpp
+	gdk-event-latency-tracker.cpp
+
+
+	# ------
+	# Header
+	demangle.h
+	event-tracker.h
+	event.h
+	gc-heap.h
+	gdk-event-latency-tracker.h
+	heap.h
+	log-display-config.h
+	logger.h
+	simple-event.h
+	sysv-heap.h
+	timestamp.h
+)
+
+# add_inkscape_lib(debug_LIB "${debug_SRC}")
+add_inkscape_source("${debug_SRC}")
diff --git a/src/debug/demangle.cpp b/src/debug/demangle.cpp
new file mode 100644
index 0000000..abf046b
--- /dev/null
+++ b/src/debug/demangle.cpp
@@ -0,0 +1,60 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Inkscape::Debug::demangle - demangle C++ symbol names
+ *
+ * Authors:
+ *   MenTaLguY <mental@rydia.net>
+ *
+ * Copyright (C) 2006 MenTaLguY
+ *
+ * Released under GNU GPL v2+, read the file 'COPYING' for more information.
+ */
+
+#include <boost/core/demangle.hpp>
+#include <cstring>
+#include <map>
+#include <memory>
+#include <string>
+#include "debug/demangle.h"
+
+namespace Inkscape {
+
+namespace Debug {
+
+namespace {
+
+struct string_less_than {
+    bool operator()(char const *a, char const *b) const {
+        return ( strcmp(a, b) < 0 );
+    }
+};
+
+typedef std::map<char const *, std::shared_ptr<std::string>, string_less_than> MangleCache;
+MangleCache mangle_cache;
+
+}
+
+std::shared_ptr<std::string> demangle(char const *name) {
+    MangleCache::iterator found=mangle_cache.find(name);
+    if ( found != mangle_cache.end() ) {
+        return (*found).second;
+    }
+
+    std::string result = boost::core::demangle(name);
+    return mangle_cache[name] = std::make_shared<std::string>(result);
+}
+
+}
+
+}
+
+/*
+  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 :
diff --git a/src/debug/demangle.h b/src/debug/demangle.h
new file mode 100644
index 0000000..ba747cd
--- /dev/null
+++ b/src/debug/demangle.h
@@ -0,0 +1,39 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Inkscape::Debug::demangle - demangle C++ symbol names
+ *
+ * Authors:
+ *   MenTaLguY <mental@rydia.net>
+ *
+ * Copyright (C) 2006 MenTaLguY
+ *
+ * Released under GNU GPL v2+, read the file 'COPYING' for more information.
+ */
+
+#ifndef SEEN_INKSCAPE_DEBUG_DEMANGLE_H
+#define SEEN_INKSCAPE_DEBUG_DEMANGLE_H
+
+#include <memory>
+#include <string>
+
+namespace Inkscape {
+
+namespace Debug {
+
+std::shared_ptr<std::string> demangle(char const *name);
+
+}
+
+}
+
+#endif
+/*
+  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 :
diff --git a/src/debug/event-tracker.h b/src/debug/event-tracker.h
new file mode 100644
index 0000000..a728bac
--- /dev/null
+++ b/src/debug/event-tracker.h
@@ -0,0 +1,236 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Inkscape::Debug::EventTracker - semi-automatically track event lifetimes
+ *
+ * Authors:
+ *   MenTaLguY <mental@rydia.net>
+ *
+ * Copyright (C) 2005 MenTaLguY
+ *
+ * Released under GNU GPL v2+, read the file 'COPYING' for more information.
+ */
+
+#ifndef SEEN_INKSCAPE_DEBUG_EVENT_TRACKER_H
+#define SEEN_INKSCAPE_DEBUG_EVENT_TRACKER_H
+
+#include "debug/logger.h"
+
+namespace Inkscape {
+
+namespace Debug {
+
+#ifdef NDEBUG
+// Make event tracking a no-op for non-debug builds
+template <typename = void> struct EventTracker {
+    template <typename... Args> EventTracker(Args &&...) {}
+    template <typename, typename... Args> void set(Args &&...) {}
+    void clear() {}
+};
+#else
+
+struct NoInitialEvent {};
+
+template <typename Event=NoInitialEvent> class EventTracker;
+
+class EventTrackerBase {
+public:
+    virtual ~EventTrackerBase() {
+        if (_active) {
+            Logger::finish();
+        }
+    }
+
+    template <typename EventType>
+    inline void set() {
+        if (_active) {
+            Logger::finish();
+        }
+        Logger::start<EventType>();
+        _active = true;
+    }
+
+    template <typename EventType, typename A>
+    inline void set(A const &a) {
+        if (_active) {
+            Logger::finish();
+        }
+        Logger::start<EventType>(a);
+        _active = true;
+    }
+
+    template <typename EventType, typename A, typename B>
+    inline void set(A const &a, B const &b) {
+        if (_active) {
+            Logger::finish();
+        }
+        Logger::start<EventType>(a, b);
+        _active = true;
+    }
+
+    template <typename EventType, typename A, typename B, typename C>
+    inline void set(A const &a, B const &b, C const &c) {
+        if (_active) {
+            Logger::finish();
+        }
+        Logger::start<EventType>(a, b, c);
+        _active = true;
+    }
+
+    template <typename EventType, typename A, typename B,
+                                  typename C, typename D>
+    inline void set(A const &a, B const &b, C const &c, D const &d) {
+        if (_active) {
+            Logger::finish();
+        }
+        Logger::start<EventType>(a, b, c, d);
+        _active = true;
+    }
+
+    template <typename EventType, typename A, typename B, typename C,
+                                  typename D, typename E>
+    inline void set(A const &a, B const &b, C const &c, D const &d, E const &e)
+    {
+        if (_active) {
+            Logger::finish();
+        }
+        Logger::start<EventType>(a, b, c, d, e);
+        _active = true;
+    }
+
+    template <typename EventType, typename A, typename B, typename C,
+                                  typename D, typename E, typename F>
+    inline void set(A const &a, B const &b, C const &c,
+                    D const &d, E const &e, F const &f)
+    {
+        if (_active) {
+            Logger::finish();
+        }
+        Logger::start<EventType>(a, b, c, d, e, f);
+        _active = true;
+    }
+
+    template <typename EventType, typename A, typename B, typename C,
+                                  typename D, typename E, typename F,
+                                  typename G>
+    inline void set(A const &a, B const &b, C const &c, D const &d,
+                    E const &e, F const &f, G const &g)
+    {
+        if (_active) {
+            Logger::finish();
+        }
+        Logger::start<EventType>(a, b, c, d, e, f, g);
+        _active = true;
+    }
+
+    template <typename EventType, typename A, typename B, typename C,
+                                  typename D, typename E, typename F,
+                                  typename G, typename H>
+    inline void set(A const &a, B const &b, C const &c, D const &d,
+                    E const &e, F const &f, G const &g, H const &h)
+    {
+        if (_active) {
+            Logger::finish();
+        }
+        Logger::start<EventType>(a, b, c, d, e, f, g, h);
+        _active = true;
+    }
+
+    void clear() {
+        if (_active) {
+            Logger::finish();
+            _active = false;
+        }
+    }
+
+protected:
+    EventTrackerBase(bool active) : _active(active) {}
+
+private:
+    EventTrackerBase(EventTrackerBase const &) = delete; // no copy
+    void operator=(EventTrackerBase const &) = delete; // no assign
+    bool _active;
+};
+
+template <typename EventType> class EventTracker : public EventTrackerBase {
+public:
+    EventTracker() : EventTrackerBase(true) { Logger::start<EventType>(); }
+
+    template <typename A>
+    EventTracker(A const &a) : EventTrackerBase(true) {
+        Logger::start<EventType>(a);
+    }
+
+    template <typename A, typename B>
+    EventTracker(A const &a, B const &b) : EventTrackerBase(true) {
+        Logger::start<EventType>(a, b);
+    }
+
+    template <typename A, typename B, typename C>
+    EventTracker(A const &a, B const &b, C const &c) : EventTrackerBase(true) {
+        Logger::start<EventType>(a, b, c);
+    }
+
+    template <typename A, typename B, typename C, typename D>
+    EventTracker(A const &a, B const &b, C const &c, D const &d)
+    : EventTrackerBase(true)
+    {
+        Logger::start<EventType>(a, b, c, d);
+    }
+
+    template <typename A, typename B, typename C, typename D, typename E>
+    EventTracker(A const &a, B const &b, C const &c, D const &d, E const &e)
+    : EventTrackerBase(true)
+    {
+        Logger::start<EventType>(a, b, c, d, e);
+    }
+
+    template <typename A, typename B, typename C, typename D,
+              typename E, typename F>
+    EventTracker(A const &a, B const &b, C const &c, D const &d,
+                 E const &e, F const &f)
+    : EventTrackerBase(true)
+    {
+        Logger::start<EventType>(a, b, c, d, e, f);
+    }
+
+    template <typename A, typename B, typename C, typename D,
+              typename E, typename F, typename G>
+    EventTracker(A const &a, B const &b, C const &c, D const &d,
+                 E const &e, F const &f, G const &g)
+    : EventTrackerBase(true)
+    {
+        Logger::start<EventType>(a, b, c, d, e, f, g);
+    }
+
+    template <typename A, typename B, typename C, typename D,
+              typename E, typename F, typename G, typename H>
+    EventTracker(A const &a, B const &b, C const &c, D const &d,
+                 E const &e, F const &f, G const &g, H const &h)
+    : EventTrackerBase(true)
+    {
+        Logger::start<EventType>(a, b, c, d, e, f, g, h);
+    }
+};
+
+template <> class EventTracker<NoInitialEvent> : public EventTrackerBase {
+public:
+    EventTracker() : EventTrackerBase(false) {}
+};
+
+#endif
+
+}
+
+}
+
+#endif
+/*
+  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 :
diff --git a/src/debug/event.h b/src/debug/event.h
new file mode 100644
index 0000000..3bc6089
--- /dev/null
+++ b/src/debug/event.h
@@ -0,0 +1,81 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Inkscape::Debug::Event - event for debug tracing
+ *
+ * Authors:
+ *   MenTaLguY <mental@rydia.net>
+ *
+ * Copyright (C) 2005 MenTaLguY
+ *
+ * Released under GNU GPL v2+, read the file 'COPYING' for more information.
+ */
+
+#ifndef SEEN_INKSCAPE_DEBUG_EVENT_H
+#define SEEN_INKSCAPE_DEBUG_EVENT_H
+
+#include <memory>
+#include <string>
+#include <utility>
+
+namespace Inkscape {
+
+namespace Debug {
+
+class Event {
+public:
+    virtual ~Event() = default;
+
+    enum Category {
+        CORE=0,
+        XML,
+        SPOBJECT,
+        DOCUMENT,
+        REFCOUNT,
+        EXTENSION,
+        FINALIZERS,
+        INTERACTION,
+        CONFIGURATION,
+        OTHER
+    };
+    enum { N_CATEGORIES=OTHER+1 };
+
+    struct PropertyPair {
+    public:
+        PropertyPair() = default;
+        PropertyPair(char const *n, std::shared_ptr<std::string>&& v)
+        : name(n), value(std::move(v)) {}
+        PropertyPair(char const *n, char const *v)
+        : name(n),
+          value(std::make_shared<std::string>(v)) {}
+
+        char const *name;
+        std::shared_ptr<std::string> value;
+    };
+
+    static Category category() { return OTHER; }
+
+    // To reduce allocations, we assume the name here is always allocated statically and will never
+    // need to be deallocated.  It would be nice to be able to assert that during the creation of
+    // the Event though.
+    virtual char const *name() const=0;
+    virtual unsigned propertyCount() const=0;
+    virtual PropertyPair property(unsigned property) const=0;
+
+    virtual void generateChildEvents() const=0;
+};
+
+}
+
+}
+
+#endif
+/*
+  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 :
diff --git a/src/debug/gc-heap.h b/src/debug/gc-heap.h
new file mode 100644
index 0000000..e0fd8f1
--- /dev/null
+++ b/src/debug/gc-heap.h
@@ -0,0 +1,53 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Inkscape::Debug::GCHeap - heap statistics for libgc heap
+ *
+ * Authors:
+ *   MenTaLguY <mental@rydia.net>
+ *
+ * Copyright (C) 2004 MenTaLguY
+ *
+ * Released under GNU GPL v2+, read the file 'COPYING' for more information.
+ */
+
+#ifndef SEEN_INKSCAPE_DEBUG_GC_HEAP_H
+#define SEEN_INKSCAPE_DEBUG_GC_HEAP_H
+
+#include "inkgc/gc-core.h"
+#include "debug/heap.h"
+
+namespace Inkscape {
+namespace Debug {
+
+class GCHeap : public Debug::Heap {
+public:
+    int features() const override {
+        return SIZE_AVAILABLE | USED_AVAILABLE | GARBAGE_COLLECTED;
+    }
+    char const *name() const override {
+        return "libgc";
+    }
+    Heap::Stats stats() const override {
+        Stats stats;
+        stats.size = GC::Core::get_heap_size();
+        stats.bytes_used = stats.size - GC::Core::get_free_bytes();
+        return stats;
+    }
+    void force_collect() override { GC::Core::gcollect(); }
+};
+
+}
+}
+
+#endif
+
+/*
+  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 :
diff --git a/src/debug/gdk-event-latency-tracker.cpp b/src/debug/gdk-event-latency-tracker.cpp
new file mode 100644
index 0000000..db93912
--- /dev/null
+++ b/src/debug/gdk-event-latency-tracker.cpp
@@ -0,0 +1,81 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Inkscape::Debug::GdkEventLatencyTracker - tracks backlog of GDK events
+ *
+ * Authors:
+ *   MenTaLguY <mental@rydia.net>
+ *
+ * Copyright (C) 2008 MenTaLguY
+ *
+ * Released under GNU GPL v2+, read the file 'COPYING' for more information.
+ */
+
+#include <gdk/gdk.h>
+
+#include "debug/gdk-event-latency-tracker.h"
+#include "preferences.h"
+
+namespace Inkscape {
+namespace Debug {
+
+GdkEventLatencyTracker::GdkEventLatencyTracker()
+    : start_seconds(0.0), max_latency(0.0), skew(1.0), last_elapsed(0.0), last_seconds(0.0)
+{
+    elapsed.stop();
+    elapsed.reset();
+}
+
+std::optional<double> GdkEventLatencyTracker::process(GdkEvent const *event) {
+    guint32 const timestamp=gdk_event_get_time(const_cast<GdkEvent *>(event));
+    if (timestamp == GDK_CURRENT_TIME) {
+        return std::optional<double>();
+    }
+    double const timestamp_seconds = timestamp / 1000.0;
+
+    if (start_seconds == 0.0) {
+        elapsed.start();
+        start_seconds = timestamp_seconds;
+        Inkscape::Preferences *prefs = Inkscape::Preferences::get();
+        skew = prefs->getDoubleLimited("/debug/latency/skew", 1.0, 0.5, 2.0);
+        return std::optional<double>(0.0);
+    } else {
+        last_elapsed = elapsed.elapsed();
+        last_seconds = timestamp_seconds;
+        double const current_seconds = (last_elapsed * skew) + start_seconds;
+        double delta = current_seconds - timestamp_seconds;
+        if (delta < 0.0) {
+            start_seconds += -delta;
+            delta = 0.0;
+        } else if (delta > max_latency) {
+            max_latency = delta;
+        }
+        return std::optional<double>(delta);
+    }
+}
+
+double GdkEventLatencyTracker::getSkew() {
+    double val = 0.0;
+    if ((last_elapsed > 0.0) && (last_seconds > 0.0)) {
+        val = (last_seconds - start_seconds) / last_elapsed;
+    }
+    return val;
+}
+
+GdkEventLatencyTracker &GdkEventLatencyTracker::default_tracker() {
+    static GdkEventLatencyTracker tracker;
+    return tracker;
+}
+
+}
+}
+
+/*
+  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 :
diff --git a/src/debug/gdk-event-latency-tracker.h b/src/debug/gdk-event-latency-tracker.h
new file mode 100644
index 0000000..569e53a
--- /dev/null
+++ b/src/debug/gdk-event-latency-tracker.h
@@ -0,0 +1,57 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Inkscape::Debug::GdkEventLatencyTracker - tracks backlog of GDK events
+ *
+ * Authors:
+ *   MenTaLguY <mental@rydia.net>
+ *
+ * Copyright (C) 2008 MenTaLguY
+ *
+ * Released under GNU GPL v2+, read the file 'COPYING' for more information.
+ */
+
+#ifndef SEEN_INKSCAPE_DEBUG_GDK_EVENT_LATENCY_TRACKER_H
+#define SEEN_INKSCAPE_DEBUG_GDK_EVENT_LATENCY_TRACKER_H
+
+typedef union _GdkEvent GdkEvent;
+#include <glibmm/timer.h>
+#include <optional>
+
+namespace Inkscape {
+namespace Debug {
+
+class GdkEventLatencyTracker {
+public:
+    GdkEventLatencyTracker();
+    std::optional<double> process(GdkEvent const *e);
+    double maxLatency() const { return max_latency; }
+    double getSkew();
+
+    static GdkEventLatencyTracker &default_tracker();
+
+private:
+    GdkEventLatencyTracker(GdkEventLatencyTracker const &) = delete; // no copy
+    void operator=(GdkEventLatencyTracker const &) = delete; // no assign
+
+    double start_seconds;
+    double max_latency;
+    double skew;
+    double last_elapsed;
+    double last_seconds;
+    Glib::Timer elapsed;
+};
+
+}
+}
+
+#endif
+/*
+  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 :
diff --git a/src/debug/heap.cpp b/src/debug/heap.cpp
new file mode 100644
index 0000000..ce9cacf
--- /dev/null
+++ b/src/debug/heap.cpp
@@ -0,0 +1,62 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Inkscape::Debug::Heap - interface for gathering heap statistics
+ *
+ * Authors:
+ *   MenTaLguY <mental@rydia.net>
+ *
+ * Copyright (C) 2005 MenTaLguY
+ *
+ * Released under GNU GPL v2+, read the file 'COPYING' for more information.
+ */
+
+#include "inkgc/gc-alloc.h"
+#include "debug/gc-heap.h"
+#include "debug/sysv-heap.h"
+#include <vector>
+
+namespace Inkscape {
+namespace Debug {
+
+namespace {
+
+typedef std::vector<Heap *, GC::Alloc<Heap *, GC::MANUAL> > HeapCollection;
+
+HeapCollection &heaps() {
+    static bool is_initialized=false;
+    static HeapCollection heaps;
+    if (!is_initialized) {
+        heaps.push_back(new SysVHeap());
+        heaps.push_back(new GCHeap());
+        is_initialized = true;
+    }
+    return heaps;
+}
+
+}
+
+unsigned heap_count() {
+    return heaps().size();
+}
+
+Heap *get_heap(unsigned i) {
+    return heaps()[i];
+}
+
+void register_extra_heap(Heap &heap) {
+    heaps().push_back(&heap);
+}
+
+}
+}
+
+/*
+  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 :
diff --git a/src/debug/heap.h b/src/debug/heap.h
new file mode 100644
index 0000000..81e7b73
--- /dev/null
+++ b/src/debug/heap.h
@@ -0,0 +1,63 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Inkscape::Debug::Heap - interface for gathering heap statistics
+ *
+ * Authors:
+ *   MenTaLguY <mental@rydia.net>
+ *
+ * Copyright (C) 2005 MenTaLguY
+ *
+ * Released under GNU GPL v2+, read the file 'COPYING' for more information.
+ */
+
+#ifndef SEEN_INKSCAPE_DEBUG_HEAP_H
+#define SEEN_INKSCAPE_DEBUG_HEAP_H
+
+#include <cstddef>
+
+namespace Inkscape {
+
+namespace Debug {
+
+class Heap {
+public:
+    virtual ~Heap() = default;
+
+    struct Stats {
+        std::size_t size;
+        std::size_t bytes_used;
+    };
+
+    enum {
+        SIZE_AVAILABLE    = ( 1 << 0 ),
+        USED_AVAILABLE    = ( 1 << 1 ),
+        GARBAGE_COLLECTED = ( 1 << 2 )
+    };
+
+    virtual int features() const=0;
+
+    virtual char const *name() const=0;
+    virtual Stats stats() const=0;
+    virtual void force_collect()=0;
+};
+
+unsigned heap_count();
+Heap *get_heap(unsigned i);
+
+void register_extra_heap(Heap &heap);
+
+}
+
+}
+
+#endif
+/*
+  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 :
diff --git a/src/debug/log-display-config.cpp b/src/debug/log-display-config.cpp
new file mode 100644
index 0000000..7de69be
--- /dev/null
+++ b/src/debug/log-display-config.cpp
@@ -0,0 +1,79 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Inkscape::Debug::log_display_config - log display configuration
+ *
+ * Authors:
+ *   MenTaLguY <mental@rydia.net>
+ *
+ * Copyright (C) 2007 MenTaLguY
+ *
+ * Released under GNU GPL v2+, read the file 'COPYING' for more information.
+ */
+
+#include <iostream>
+#include <gtk/gtk.h>
+#include <gdk/gdk.h>
+#include "debug/event-tracker.h"
+#include "debug/logger.h"
+#include "debug/simple-event.h"
+#include "debug/log-display-config.h"
+
+namespace Inkscape {
+
+namespace Debug {
+
+namespace {
+
+typedef SimpleEvent<Event::CONFIGURATION> ConfigurationEvent;
+
+class Monitor : public ConfigurationEvent {
+public:
+    Monitor(GdkMonitor *monitor)
+        : ConfigurationEvent("monitor")
+    {
+        GdkRectangle area;
+        gdk_monitor_get_geometry(monitor, &area);
+
+        _addProperty("x", area.x);
+        _addProperty("y", area.y);
+        _addProperty("width", area.width);
+        _addProperty("height", area.height);
+    }
+};
+
+class Display : public ConfigurationEvent {
+public:
+    Display() : ConfigurationEvent("display") {}
+    void generateChildEvents() const override {
+        GdkDisplay *display=gdk_display_get_default();
+
+        gint const n_monitors = gdk_display_get_n_monitors(display);
+
+        // Loop through all monitors and log their details
+        for (gint i_monitor = 0; i_monitor < n_monitors; ++i_monitor) {
+            GdkMonitor *monitor = gdk_display_get_monitor(display, i_monitor);
+            Logger::write<Monitor>(monitor);
+        }
+    }
+};
+
+}
+
+void log_display_config() {
+    Logger::write<Display>();
+}
+
+}
+
+}
+
+/*
+  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 :
diff --git a/src/debug/log-display-config.h b/src/debug/log-display-config.h
new file mode 100644
index 0000000..df9be18
--- /dev/null
+++ b/src/debug/log-display-config.h
@@ -0,0 +1,36 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Inkscape::Debug::log_display_config - log display configuration
+ *
+ * Authors:
+ *   MenTaLguY <mental@rydia.net>
+ *
+ * Copyright (C) 2007 MenTaLguY
+ *
+ * Released under GNU GPL v2+, read the file 'COPYING' for more information.
+ */
+
+#ifndef SEEN_INKSCAPE_DEBUG_LOG_DISPLAY_CONFIG_H
+#define SEEN_INKSCAPE_DEBUG_LOG_DISPLAY_CONFIG_H
+
+namespace Inkscape {
+
+namespace Debug {
+
+void log_display_config();
+
+}
+
+}
+
+#endif
+/*
+  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 :
diff --git a/src/debug/logger.cpp b/src/debug/logger.cpp
new file mode 100644
index 0000000..37b8221
--- /dev/null
+++ b/src/debug/logger.cpp
@@ -0,0 +1,231 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Inkscape::Debug::Logger - debug logging facility
+ *
+ * Authors:
+ *   MenTaLguY <mental@rydia.net>
+ *
+ * Copyright (C) 2005 MenTaLguY
+ *
+ * Released under GNU GPL v2+, read the file 'COPYING' for more information.
+ */
+
+#include <cstring>
+#include <fstream>
+#include <memory>
+#include <string>
+#include <vector>
+#include <glib.h>
+#include "inkscape-version.h"
+#include "debug/logger.h"
+#include "debug/simple-event.h"
+
+namespace Inkscape {
+
+namespace Debug {
+
+bool Logger::_enabled=false;
+bool Logger::_category_mask[Event::N_CATEGORIES];
+
+namespace {
+
+static void write_escaped_value(std::ostream &os, char const *value) {
+    for ( char const *current=value ; *current ; ++current ) {
+        switch (*current) {
+        case '&':
+            os << "&amp;";
+            break;
+        case '"':
+            os << "&quot;";
+            break;
+        case '\'':
+            os << "&apos;";
+            break;
+        case '<':
+            os << "&lt;";
+            break;
+        case '>':
+            os << "&gt;";
+            break;
+        default:
+            os.put(*current);
+        }
+    }
+}
+
+static void write_indent(std::ostream &os, unsigned depth) {
+    for ( unsigned i = 0 ; i < depth ; i++ ) {
+        os.write("  ", 2);
+    }
+}
+
+static std::ofstream log_stream;
+static bool empty_tag=false;
+typedef std::vector<std::shared_ptr<std::string>> TagStack;
+static TagStack &tag_stack() {
+    static TagStack stack;
+    return stack;
+}
+
+static void do_shutdown() {
+    Debug::Logger::shutdown();
+}
+
+static bool equal_range(char const *c_string,
+                        char const *start, char const *end)
+{
+    return !std::strncmp(start, c_string, end - start) &&
+           !c_string[end - start];
+}
+
+static void set_category_mask(bool * const mask, char const *filter) {
+    if (!filter) {
+        for ( unsigned i = 0 ; i < Event::N_CATEGORIES ; i++ ) {
+            mask[i] = true;
+        }
+        return;
+    } else {
+        for ( unsigned i = 0 ; i < Event::N_CATEGORIES ; i++ ) {
+            mask[i] = false;
+        }
+        mask[Event::CORE] = true;
+    }
+
+    char const *start;
+    char const *end;
+    start = end = filter;
+    while (*end) {
+        while ( *end && *end != ',' ) { end++; }
+        if ( start != end ) {
+            struct CategoryName {
+                char const *name;
+                Event::Category category;
+            };
+            static const CategoryName category_names[] = {
+                { "CORE", Event::CORE },
+                { "XML", Event::XML },
+                { "SPOBJECT", Event::SPOBJECT },
+                { "DOCUMENT", Event::DOCUMENT },
+                { "REFCOUNT", Event::REFCOUNT },
+                { "EXTENSION", Event::EXTENSION },
+                { "FINALIZERS", Event::FINALIZERS },
+                { "INTERACTION", Event::INTERACTION },
+                { "CONFIGURATION", Event::CONFIGURATION },
+                { "OTHER", Event::OTHER },
+                { nullptr, Event::OTHER }
+            };
+            CategoryName const *iter;
+            for ( iter = category_names ; iter->name ; iter++ ) {
+                if (equal_range(iter->name, start, end)) {
+                    mask[iter->category] = true;
+                    break;
+                }
+            }
+            if (!iter->name) {
+                g_warning("Unknown debugging category %*s", (int)(end - start), start);
+            }
+        }
+        if (*end) {
+            start = end = end + 1;
+        }
+    }
+}
+
+typedef SimpleEvent<Event::CORE> CoreEvent;
+
+class SessionEvent : public CoreEvent {
+public:
+    SessionEvent() : CoreEvent("session") {
+        _addProperty("inkscape-version", Inkscape::version_string);
+    }
+};
+
+}
+
+void Logger::init() {
+    if (!_enabled) {
+        char const *log_filename=std::getenv("INKSCAPE_DEBUG_LOG");
+        if (log_filename) {
+            log_stream.open(log_filename);
+            if (log_stream.is_open()) {
+                char const *log_filter=std::getenv("INKSCAPE_DEBUG_FILTER");
+                set_category_mask(_category_mask, log_filter);
+                log_stream << "<?xml version=\"1.0\"?>\n";
+                log_stream.flush();
+                _enabled = true;
+                start<SessionEvent>();
+                std::atexit(&do_shutdown);
+            }
+        }
+    }
+}
+
+void Logger::_start(Event const &event) {
+    char const *name=event.name();
+
+    if (empty_tag) {
+        log_stream << ">\n";
+    }
+
+    write_indent(log_stream, tag_stack().size());
+
+    log_stream << "<" << name;
+
+    unsigned property_count=event.propertyCount();
+    for ( unsigned i = 0 ; i < property_count ; i++ ) {
+        Event::PropertyPair property=event.property(i);
+        log_stream << " " << property.name << "=\"";
+        write_escaped_value(log_stream, property.value->c_str());
+        log_stream << "\"";
+    }
+
+    log_stream.flush();
+
+    tag_stack().push_back(std::make_shared<std::string>(name));
+    empty_tag = true;
+
+    event.generateChildEvents();
+}
+
+void Logger::_skip() {
+    tag_stack().push_back(nullptr);
+}
+
+void Logger::_finish() {
+    if (tag_stack().back()) {
+        if (empty_tag) {
+            log_stream << "/>\n";
+        } else {
+            write_indent(log_stream, tag_stack().size() - 1);
+            log_stream << "</" << tag_stack().back()->c_str() << ">\n";
+        }
+        log_stream.flush();
+
+        empty_tag = false;
+    }
+
+    tag_stack().pop_back();
+}
+
+void Logger::shutdown() {
+    if (_enabled) {
+        while (!tag_stack().empty()) {
+            finish();
+        }
+    }
+}
+
+}
+
+}
+
+/*
+  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 :
diff --git a/src/debug/logger.h b/src/debug/logger.h
new file mode 100644
index 0000000..ab6c826
--- /dev/null
+++ b/src/debug/logger.h
@@ -0,0 +1,247 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Inkscape::Debug::Logger - debug logging facility
+ *
+ * Authors:
+ *   MenTaLguY <mental@rydia.net>
+ *
+ * Copyright (C) 2005 MenTaLguY
+ *
+ * Released under GNU GPL v2+, read the file 'COPYING' for more information.
+ */
+
+#ifndef SEEN_INKSCAPE_DEBUG_LOGGER_H
+#define SEEN_INKSCAPE_DEBUG_LOGGER_H
+
+#include "debug/event.h"
+
+namespace Inkscape {
+
+namespace Debug {
+
+class Logger {
+public:
+    static void init();
+
+    template <typename EventType>
+    inline static void start() {
+        if (_enabled) {
+            if (_category_mask[EventType::category()]) {
+                _start(EventType());
+            } else {
+                _skip();
+            }
+        }
+    }
+
+    template <typename EventType, typename A>
+    inline static void start(A const &a) {
+        if (_enabled) {
+            if (_category_mask[EventType::category()]) {
+                _start(EventType(a));
+            } else {
+                _skip();
+            }
+        }
+    }
+
+    template <typename EventType, typename A, typename B>
+    inline static void start(A const &a, B const &b) {
+        if (_enabled) {
+            if (_category_mask[EventType::category()]) {
+                _start(EventType(a, b));
+            } else {
+                _skip();
+            }
+        }
+    }
+
+    template <typename EventType, typename A, typename B, typename C>
+    inline static void start(A const &a, B const &b, C const &c) {
+        if (_enabled) {
+            if (_category_mask[EventType::category()]) {
+                _start(EventType(a, b, c));
+            } else {
+                _skip();
+            }
+        }
+    }
+
+    template <typename EventType, typename A, typename B,
+                                  typename C, typename D>
+    inline static void start(A const &a, B const &b, C const &c, D const &d) {
+        if (_enabled) {
+            if (_category_mask[EventType::category()]) {
+                _start(EventType(a, b, c, d));
+            } else {
+                _skip();
+            }
+        }
+    }
+
+    template <typename EventType, typename A, typename B, typename C,
+                                  typename D, typename E>
+    inline static void start(A const &a, B const &b, C const &c,
+                             D const &d, E const &e)
+    {
+        if (_enabled) {
+            if (_category_mask[EventType::category()]) {
+                _start(EventType(a, b, c, d, e));
+            } else {
+                _skip();
+            }
+        }
+    }
+
+    template <typename EventType, typename A, typename B, typename C,
+                                  typename D, typename E, typename F>
+    inline static void start(A const &a, B const &b, C const &c,
+                             D const &d, E const &e, F const &f)
+    {
+        if (_enabled) {
+            if (_category_mask[EventType::category()]) {
+                _start(EventType(a, b, c, d, e, f));
+            } else {
+                _skip();
+            }
+        }
+    }
+
+    template <typename EventType, typename A, typename B, typename C,
+                                  typename D, typename E, typename F,
+                                  typename G>
+    inline static void start(A const &a, B const &b, C const &c, D const &d,
+                             E const &e, F const &f, G const &g)
+    {
+        if (_enabled) {
+            if (_category_mask[EventType::category()]) {
+                _start(EventType(a, b, c, d, e, f, g));
+            } else {
+                _skip();
+            }
+        }
+    }
+
+    template <typename EventType, typename A, typename B, typename C,
+                                  typename D, typename E, typename F,
+                                  typename G, typename H>
+    inline static void start(A const &a, B const &b, C const &c, D const &d,
+                             E const &e, F const &f, G const &g, H const &h)
+    {
+        if (_enabled) {
+            if (_category_mask[EventType::category()]) {
+                _start(EventType(a, b, c, d, e, f, g, h));
+            } else {
+                _skip();
+            }
+        }
+    }
+
+    inline static void finish() {
+        if (_enabled) {
+            _finish();
+        }
+    }
+
+    template <typename EventType>
+    inline static void write() {
+        start<EventType>();
+        finish();
+    }
+
+    template <typename EventType, typename A>
+    inline static void write(A const &a) {
+        start<EventType, A>(a);
+        finish();
+    }
+
+    template <typename EventType, typename A, typename B>
+    inline static void write(A const &a, B const &b) {
+        start<EventType, A, B>(a, b);
+        finish();
+    }
+
+    template <typename EventType, typename A, typename B, typename C>
+    inline static void write(A const &a, B const &b, C const &c) {
+        start<EventType, A, B, C>(a, b, c);
+        finish();
+    }
+
+    template <typename EventType, typename A, typename B,
+                                  typename C, typename D>
+    inline static void write(A const &a, B const &b, C const &c, D const &d) {
+        start<EventType, A, B, C, D>(a, b, c, d);
+        finish();
+    }
+
+    template <typename EventType, typename A, typename B,
+                                  typename C, typename D,
+                                  typename E>
+    inline static void write(A const &a, B const &b, C const &c,
+                             D const &d, E const &e)
+    {
+        start<EventType, A, B, C, D, E>(a, b, c, d, e);
+        finish();
+    }
+
+    template <typename EventType, typename A, typename B,
+                                  typename C, typename D,
+                                  typename E, typename F>
+    inline static void write(A const &a, B const &b, C const &c,
+                             D const &d, E const &e, F const &f)
+    {
+        start<EventType, A, B, C, D, E, F>(a, b, c, d, e, f);
+        finish();
+    }
+
+    template <typename EventType, typename A, typename B,
+                                  typename C, typename D,
+                                  typename E, typename F,
+                                  typename G>
+    inline static void write(A const &a, B const &b, C const &c,
+                             D const &d, E const &e, F const &f,
+                             G const &g)
+    {
+        start<EventType, A, B, C, D, E, F, G>(a, b, c, d, e, f, g);
+        finish();
+    }
+
+    template <typename EventType, typename A, typename B,
+                                  typename C, typename D,
+                                  typename E, typename F,
+                                  typename G, typename H>
+    inline static void write(A const &a, B const &b, C const &c,
+                             D const &d, E const &e, F const &f,
+                             G const &g, H const &h)
+    {
+        start<EventType, A, B, C, D, E, F, G, H>(a, b, c, d, e, f, g, h);
+        finish();
+    }
+
+    static void shutdown();
+
+private:
+    static bool _enabled;
+
+    static void _start(Event const &event);
+    static void _skip();
+    static void _finish();
+
+    static bool _category_mask[Event::N_CATEGORIES];
+};
+
+}
+
+}
+
+#endif
+/*
+  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 :
diff --git a/src/debug/simple-event.h b/src/debug/simple-event.h
new file mode 100644
index 0000000..58719b7
--- /dev/null
+++ b/src/debug/simple-event.h
@@ -0,0 +1,87 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Inkscape::Debug::SimpleEvent - trivial implementation of Debug::Event
+ *
+ * Authors:
+ *   MenTaLguY <mental@rydia.net>
+ *
+ * Copyright (C) 2005 MenTaLguY
+ *
+ * Released under GNU GPL v2+, read the file 'COPYING' for more information.
+ */
+
+#ifndef SEEN_INKSCAPE_DEBUG_SIMPLE_EVENT_H
+#define SEEN_INKSCAPE_DEBUG_SIMPLE_EVENT_H
+
+#include <cstdarg>
+#include <memory>
+#include <string>
+#include <vector>
+#include <glib.h> // g_assert()
+
+#include "debug/event.h"
+
+namespace Inkscape {
+
+namespace Debug {
+
+template <Event::Category C=Event::OTHER>
+class SimpleEvent : public Event {
+public:
+    explicit SimpleEvent(char const *name) : _name(name) {}
+
+    // default copy
+    // default assign
+
+    static Category category() { return C; }
+
+    char const *name() const override { return _name; }
+    unsigned propertyCount() const override { return _properties.size(); }
+    PropertyPair property(unsigned property) const override {
+        return _properties[property];
+    }
+
+    void generateChildEvents() const override {}
+
+protected:
+    void _addProperty(char const *name, std::shared_ptr<std::string>&& value) {
+        _properties.emplace_back(name, std::move(value));
+    }
+    void _addProperty(char const *name, char const *value) {
+        _addProperty(name, std::make_shared<std::string>(value));
+    }
+    void _addProperty(char const *name, long value) {
+        _addFormattedProperty(name, "%ld", value);
+    }
+
+private:
+    char const *_name;
+    std::vector<PropertyPair> _properties;
+
+    void _addFormattedProperty(char const *name, char const *format, ...)
+    {
+        va_list args;
+        va_start(args, format);
+        gchar *value=g_strdup_vprintf(format, args);
+        g_assert(value != nullptr);
+        va_end(args);
+        _addProperty(name, value);
+        g_free(value);
+    }
+};
+
+}
+
+}
+
+#endif
+/*
+  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 :
diff --git a/src/debug/sysv-heap.cpp b/src/debug/sysv-heap.cpp
new file mode 100644
index 0000000..7d21c02
--- /dev/null
+++ b/src/debug/sysv-heap.cpp
@@ -0,0 +1,84 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Inkscape::Debug::SysVHeap - malloc() statistics via System V interface
+ *
+ * Authors:
+ *   MenTaLguY <mental@rydia.net>
+ *
+ * Copyright (C) 2005 MenTaLguY
+ *
+ * Released under GNU GPL v2+, read the file 'COPYING' for more information.
+ */
+
+#ifdef HAVE_CONFIG_H
+# include "config.h"  // only include where actually required!
+#endif
+
+#ifdef HAVE_MALLOC_H
+# include <malloc.h>
+#endif
+
+#include "debug/sysv-heap.h"
+
+namespace Inkscape {
+namespace Debug {
+
+int SysVHeap::features() const {
+#ifdef HAVE_MALLINFO
+    return SIZE_AVAILABLE | USED_AVAILABLE;
+#else
+    return 0;
+#endif
+}
+
+Heap::Stats SysVHeap::stats() const {
+    Stats stats = { 0, 0 };
+
+#ifdef HAVE_MALLINFO
+#ifdef HAVE_MALLINFO2
+    struct mallinfo2 info=mallinfo2();
+#else
+    struct mallinfo info=mallinfo();
+#endif
+
+#ifdef HAVE_STRUCT_MALLINFO_USMBLKS
+    stats.size += info.usmblks;
+    stats.bytes_used += info.usmblks;
+#endif
+
+#ifdef HAVE_STRUCT_MALLINFO_FSMBLKS
+    stats.size += info.fsmblks;
+#endif
+
+#ifdef HAVE_STRUCT_MALLINFO_UORDBLKS
+    stats.size += info.uordblks;
+    stats.bytes_used += info.uordblks;
+#endif
+
+#ifdef HAVE_STRUCT_MALLINFO_FORDBLKS
+    stats.size += info.fordblks;
+#endif
+
+#ifdef HAVE_STRUCT_MALLINFO_HBLKHD
+    stats.size += info.hblkhd;
+    stats.bytes_used += info.hblkhd;
+#endif
+
+#endif
+
+    return stats;
+}
+
+}
+}
+
+/*
+  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 :
diff --git a/src/debug/sysv-heap.h b/src/debug/sysv-heap.h
new file mode 100644
index 0000000..f7ed271
--- /dev/null
+++ b/src/debug/sysv-heap.h
@@ -0,0 +1,48 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Inkscape::Debug::SysVHeap - malloc() statistics via System V interface
+ *
+ * Authors:
+ *   MenTaLguY <mental@rydia.net>
+ *
+ * Copyright (C) 2005 MenTaLguY
+ *
+ * Released under GNU GPL v2+, read the file 'COPYING' for more information.
+ */
+
+#ifndef SEEN_INKSCAPE_DEBUG_SYSV_HEAP_H
+#define SEEN_INKSCAPE_DEBUG_SYSV_HEAP_H
+
+#include "debug/heap.h"
+
+namespace Inkscape {
+namespace Debug {
+
+class SysVHeap : public Heap {
+public:
+    SysVHeap() = default;
+    
+    int features() const override;
+
+    char const *name() const override {
+        return "standard malloc()";
+    }
+    Stats stats() const override;
+    void force_collect() override {}
+};
+
+}
+}
+
+#endif
+
+/*
+  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 :
diff --git a/src/debug/timestamp.cpp b/src/debug/timestamp.cpp
new file mode 100644
index 0000000..dab4e73
--- /dev/null
+++ b/src/debug/timestamp.cpp
@@ -0,0 +1,46 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Inkscape::Debug::SimpleEvent - trivial implementation of Debug::Event
+ *
+ * Authors:
+ *   MenTaLguY <mental@rydia.net>
+ *
+ * Copyright (C) 2007 MenTaLguY
+ *
+ * Released under GNU GPL v2+, read the file 'COPYING' for more information.
+ */
+
+
+#include <glib.h>
+#include <glibmm/ustring.h>
+#include <memory>
+#include <string>
+#include "debug/simple-event.h"
+#include "timestamp.h"
+
+namespace Inkscape {
+
+namespace Debug {
+
+std::shared_ptr<std::string> timestamp() {
+    gint64 micr = g_get_monotonic_time();
+    gchar *value = g_strdup_printf("%.6f", (gdouble)micr / 1000000.0);
+    std::shared_ptr<std::string> result = std::make_shared<std::string>(value);
+    g_free(value);
+    return result;
+}
+
+}
+
+}
+
+/*
+  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 :
diff --git a/src/debug/timestamp.h b/src/debug/timestamp.h
new file mode 100644
index 0000000..a4db90d
--- /dev/null
+++ b/src/debug/timestamp.h
@@ -0,0 +1,39 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Inkscape::Debug::timestamp - timestamp strings
+ *
+ * Authors:
+ *   MenTaLguY <mental@rydia.net>
+ *
+ * Copyright (C) 2007 MenTaLguY
+ *
+ * Released under GNU GPL v2+, read the file 'COPYING' for more information.
+ */
+
+#ifndef SEEN_INKSCAPE_DEBUG_TIMESTAMP_H
+#define SEEN_INKSCAPE_DEBUG_TIMESTAMP_H
+
+#include <memory>
+#include <string>
+
+namespace Inkscape {
+
+namespace Debug {
+
+std::shared_ptr<std::string> timestamp();
+
+}
+
+}
+
+#endif
+/*
+  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 :