LibVT+Kernel: Clean up scroll API

This commit cleans up some of the `#ifdef`-ed code smell in
`Terminal`, by extending the scroll APIs to take a range of lines as a
parameter. This makes it possible to use the same code for `IL`/`DL` as
for scrolling.

Note that the current scrolling implementation is very naive, and does
many insertions/deletions in the middle of arrays, whereas swaps should
be enough. This optimization will come in a later commit.

The `linefeed` override was removed from `VirtualConsole`. Previously,
it exhibited incorrect behavior by moving to column 0. Now that we use
the method defined in `Terminal`, code which relied on this behavior
stopped working. We go instead go through the TTY layer which handles
the various output flags. Passing the input character-by-character
seems a bit excessive, so a fix for it will come in another PR.

1 files changed, 4 insertions, 9 deletions

diff --git a/Kernel/TTY/VirtualConsole.h b/Kernel/TTY/VirtualConsole.h
index fe0b62a23c..69f6eecf90 100644
--- a/Kernel/TTY/VirtualConsole.h
+++ b/Kernel/TTY/VirtualConsole.h
@@ -37,17 +37,12 @@ private:
     virtual void clear() override;
     virtual void clear_including_history() override;
 
-    virtual void scroll_up() override;
-    virtual void scroll_down() override;
-    virtual void linefeed() override;
+    virtual void scroll_up(u16 region_top, u16 region_bottom, size_t count) override;
+    virtual void scroll_down(u16 region_top, u16 region_bottom, size_t count) override;
     virtual void put_character_at(unsigned row, unsigned column, u32 ch) override;
-    virtual void set_window_title(const String&) override;
 
     virtual void ICH(Parameters) override;
-
-    virtual void IL(Parameters) override;
     virtual void DCH(Parameters) override;
-    virtual void DL(Parameters) override;
 };
 
 class VirtualConsole final : public TTY
@@ -140,8 +135,8 @@ private:
 
     void on_code_point(u32);
 
-    void scroll_down();
-    void scroll_up();
+    void scroll_down(u16 region_top, u16 region_bottom, size_t count);
+    void scroll_up(u16 region_top, u16 region_bottom, size_t count);
     void clear_line(size_t index);
     void put_character_at(unsigned row, unsigned column, u32 ch, const VT::Attribute&);