[vte] lib: Use Timer class for mouse autoscroll timer

[Christian Persch <chpe src gnome org>]

commit fbdaa7c71b0a79bee9a8b638c4b96854be519473
Author: Christian Persch <chpe src gnome org>
Date:   Sun Dec 1 22:58:51 2019 +0100

    lib: Use Timer class for mouse autoscroll timer

 src/vte.cc         | 45 +++++++++------------------------------------
 src/vteinternal.hh |  8 +++++---
 2 files changed, 14 insertions(+), 39 deletions(-)
---
diff --git a/src/vte.cc b/src/vte.cc
index 9323090f..2eb3cd51 100644
--- a/src/vte.cc
+++ b/src/vte.cc
@@ -6759,25 +6759,15 @@ Terminal::select_all()
        invalidate_all();
 }
 
-/* Autoscroll a bit. */
-static gboolean
-vte_terminal_autoscroll_cb(vte::terminal::Terminal* that)
-{
-        return that->autoscroll() ? G_SOURCE_CONTINUE : G_SOURCE_REMOVE;
-}
-
-/*
- * Terminal::autoscroll():
- *
- * Returns: %true to continue autoscrolling, %false to stop
- */
 bool
-Terminal::autoscroll()
+Terminal::mouse_autoscroll_timer_callback() noexcept
 {
        bool extend = false;
        long x, y, xmax, ymax;
        glong adj;
 
+        auto again = bool{true};
+
        /* Provide an immediate effect for mouse wigglers. */
        if (m_mouse_last_position.y < 0) {
                if (m_vadjustment) {
@@ -6817,35 +6807,20 @@ Terminal::autoscroll()
                 modify_selection(vte::view::coords(x, y));
        } else {
                /* Stop autoscrolling. */
-               m_mouse_autoscroll_tag = 0;
+                again = false;
        }
-       return (m_mouse_autoscroll_tag != 0);
+       return again;
 }
 
 /* Start autoscroll. */
 void
 Terminal::start_autoscroll()
 {
-       if (m_mouse_autoscroll_tag != 0)
-                return;
-
-        m_mouse_autoscroll_tag =
-                g_timeout_add_full(G_PRIORITY_LOW,
-                                   666 / m_row_count, // FIXME WTF?
-                                   (GSourceFunc)vte_terminal_autoscroll_cb,
-                                   this,
-                                   NULL);// FIXME make sure m_mouse_autoscroll_tag is nulled!
-}
-
-/* Stop autoscroll. */
-void
-Terminal::stop_autoscroll()
-{
-       if (m_mouse_autoscroll_tag == 0)
+       if (m_mouse_autoscroll_timer)
                 return;
 
-        g_source_remove(m_mouse_autoscroll_tag);
-        m_mouse_autoscroll_tag = 0;
+        m_mouse_autoscroll_timer.schedule(666 / m_row_count, // FIXME WTF?
+                                          vte::glib::Timer::Priority::eLOW);
 }
 
 bool
@@ -6888,9 +6863,7 @@ Terminal::widget_motion_notify(GdkEventMotion *event)
                        if (pos.y < 0 || pos.y >= m_view_usable_extents.height()) {
                                /* Give mouse wigglers something. */
                                 stop_autoscroll();
-                               autoscroll();
-                               /* Start a timed autoscroll if we're not doing it
-                                * already. */
+                               mouse_autoscroll_timer_callback();
                                start_autoscroll();
                        }
 
diff --git a/src/vteinternal.hh b/src/vteinternal.hh
index 4740e22e..bab7f756 100644
--- a/src/vteinternal.hh
+++ b/src/vteinternal.hh
@@ -533,8 +533,11 @@ public:
          * the viewable area, and also want to catch in-cell movements if they make the pointer visible.
          */
         vte::view::coords m_mouse_last_position{-1, -1};
-        guint m_mouse_autoscroll_tag;
         double m_mouse_smooth_scroll_delta{0.0};
+        bool mouse_autoscroll_timer_callback() noexcept;
+        vte::glib::Timer m_mouse_autoscroll_timer{std::bind(&Terminal::mouse_autoscroll_timer_callback,
+                                                            this),
+                                                  "mouse-autoscroll-timer"};
 
        /* State variables for handling match checks. */
         int m_match_regex_next_tag{0};
@@ -958,9 +961,8 @@ public:
                        gint column_width,
                        gint row_height);
 
-        bool autoscroll();
         void start_autoscroll();
-        void stop_autoscroll();
+        void stop_autoscroll() noexcept { m_mouse_autoscroll_timer.abort(); }
 
         void connect_pty_read();
         void disconnect_pty_read();