[PATCH 1/4] Fix TUI source window drawing

[PATCH 1/4] Fix TUI source window drawing

[Hannes Domani]

The smaxrow and smaxcol parameters of prefresh are the bottom right corner
of the text area inclusive, not exclusive.

And if the source window grows bigger in height, the pad has to grow as
well.

gdb/ChangeLog:

2020-12-21  Hannes Domani  <ssbssa@yahoo.de>

	PR tui/26927
	* tui/tui-winsource.c (tui_source_window_base::refresh_window):
	Fix source pad size in prefresh.
	(tui_source_window_base::show_source_content): Grow source pad
	if necessary.
---
 gdb/tui/tui-winsource.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/gdb/tui/tui-winsource.c b/gdb/tui/tui-winsource.c
index b371e62459..79f233090e 100644
--- a/gdb/tui/tui-winsource.c
+++ b/gdb/tui/tui-winsource.c
@@ -262,7 +262,7 @@ tui_source_window_base::refresh_window ()
      scrolled beyond where we clip.  */
   m_horizontal_offset = pad_x;
   prefresh (m_pad.get (), 0, pad_x, y + 1, x + left_margin,
-	    y + 1 + m_content.size (), x + left_margin + view_width - 1);
+	    y + m_content.size (), x + left_margin + view_width - 1);
 }
 
 void
@@ -273,7 +273,8 @@ tui_source_window_base::show_source_content ()
   check_and_display_highlight_if_needed ();
 
   int pad_width = std::max (m_max_length, width);
-  if (m_pad == nullptr || pad_width > getmaxx (m_pad.get ()))
+  if (m_pad == nullptr || pad_width > getmaxx (m_pad.get ())
+      || m_content.size () > getmaxy (m_pad.get ()))
     m_pad.reset (newpad (m_content.size (), pad_width));
 
   werase (m_pad.get ());
-- 
2.29.2

[PATCH 2/4] Redraw both spaces between line numbers and source code

[Hannes Domani]

There a 2 spaces between the numbers and source code, but only one of
them was redrawn.
So if you increase the source window height, the second space keeps the
character of the border rectangle.

With this both spaces are redrawn, so the border rectangle character is
overwritten.

gdb/ChangeLog:

2020-12-21  Hannes Domani  <ssbssa@yahoo.de>

	* tui/tui-source.c (tui_source_window::show_line_number):
	Redraw second space after line number.
---
 gdb/tui/tui-source.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/gdb/tui/tui-source.c b/gdb/tui/tui-source.c
index cc6680406d..bdfd3de9e5 100644
--- a/gdb/tui/tui-source.c
+++ b/gdb/tui/tui-source.c
@@ -233,6 +233,6 @@ tui_source_window::show_line_number (int offset) const
 {
   int lineno = m_content[0].line_or_addr.u.line_no + offset;
   char text[20];
-  xsnprintf (text, sizeof (text), "%*d ", m_digits - 1, lineno);
+  xsnprintf (text, sizeof (text), "%*d  ", m_digits - 1, lineno);
   waddstr (handle.get (), text);
 }
-- 
2.29.2

[PATCH 3/4] Don't add window duplicates to tui_windows

[Hannes Domani]

Otherwise, each time a window size is change with 'winheight', all windows
are duplicated, and when done multiple times, slows down redrawing.

gdb/ChangeLog:

2020-12-21  Hannes Domani  <ssbssa@yahoo.de>

	* tui/tui-layout.c (tui_layout_window::apply):
	Check if tui_windows already contains the current window.
---
 gdb/tui/tui-layout.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/gdb/tui/tui-layout.c b/gdb/tui/tui-layout.c
index 2dd7c3d4ba..dd72980efd 100644
--- a/gdb/tui/tui-layout.c
+++ b/gdb/tui/tui-layout.c
@@ -424,7 +424,9 @@ tui_layout_window::apply (int x_, int y_, int width_, int height_)
   height = height_;
   gdb_assert (m_window != nullptr);
   m_window->resize (height, width, x, y);
-  tui_windows.push_back (m_window);
+  if (std::find (tui_windows.begin (), tui_windows.end (),
+		 m_window) == tui_windows.end ())
+    tui_windows.push_back (m_window);
 }
 
 /* See tui-layout.h.  */
-- 
2.29.2

[PATCH 4/4] Prevent flickering when redrawing the TUI source window

[Hannes Domani]

tui_win_info::refresh_window simply calls wrefresh, which internally
does a doupdate.
This redraws the source background window without the source pad.
Then prefresh of the source pad draws the actual source code on top,
which flickers.

By changing this to wnoutrefresh, the actual drawing on the screen is
only done once in the following prefresh, without flickering.

gdb/ChangeLog:

2020-12-21  Hannes Domani  <ssbssa@yahoo.de>

	* tui/tui-winsource.c (tui_source_window_base::refresh_window):
	Call wnoutrefresh instead of tui_win_info::refresh_window.
---
 gdb/tui/tui-winsource.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/gdb/tui/tui-winsource.c b/gdb/tui/tui-winsource.c
index 79f233090e..882ce391f7 100644
--- a/gdb/tui/tui-winsource.c
+++ b/gdb/tui/tui-winsource.c
@@ -252,7 +252,7 @@ tui_source_window_base::show_source_line (int lineno)
 void
 tui_source_window_base::refresh_window ()
 {
-  tui_win_info::refresh_window ();
+  wnoutrefresh (handle.get ());
 
   int pad_width = std::max (m_max_length, width);
   int left_margin = 1 + TUI_EXECINFO_SIZE + extra_margin ();
-- 
2.29.2

Re: [PATCH 1/4] Fix TUI source window drawing

[Tom Tromey]

>>>>> "Hannes" == Hannes Domani via Gdb-patches <gdb-patches@sourceware.org> writes:

Hannes> 2020-12-21  Hannes Domani  <ssbssa@yahoo.de>

Hannes> 	PR tui/26927
Hannes> 	* tui/tui-winsource.c (tui_source_window_base::refresh_window):
Hannes> 	Fix source pad size in prefresh.
Hannes> 	(tui_source_window_base::show_source_content): Grow source pad
Hannes> 	if necessary.

Thank you for the patch.  This is ok.

Tom

Re: [PATCH 2/4] Redraw both spaces between line numbers and source code

[Tom Tromey]

>>>>> "Hannes" == Hannes Domani via Gdb-patches <gdb-patches@sourceware.org> writes:

Hannes> 2020-12-21  Hannes Domani  <ssbssa@yahoo.de>

Hannes> 	* tui/tui-source.c (tui_source_window::show_line_number):
Hannes> 	Redraw second space after line number.

Thanks for the patch.

Hannes> -  xsnprintf (text, sizeof (text), "%*d ", m_digits - 1, lineno);
Hannes> +  xsnprintf (text, sizeof (text), "%*d  ", m_digits - 1, lineno);

Would you mind adding a brief comment here explaining the need for two
spaces?  I think that may prove useful in the future.  This is ok with
this tweak.

Tom

Re: [PATCH 3/4] Don't add window duplicates to tui_windows

[Tom Tromey]

>>>>> "Hannes" == Hannes Domani via Gdb-patches <gdb-patches@sourceware.org> writes:

Hannes> Otherwise, each time a window size is change with 'winheight', all windows
Hannes> are duplicated, and when done multiple times, slows down redrawing.

Ugh.  Thank you for finding this.

Hannes> 2020-12-21  Hannes Domani  <ssbssa@yahoo.de>

Hannes> 	* tui/tui-layout.c (tui_layout_window::apply):
Hannes> 	Check if tui_windows already contains the current window.

I gather the problem is that tui_layout_split::adjust_size is called,
but it doesn't clear the window list first.

I think this patch is safe, but I wonder whether it would be better to
instead pass a flag to apply to indicate that whether the window list
ought to be updated.

Tom

Re: [PATCH 4/4] Prevent flickering when redrawing the TUI source window

[Tom Tromey]

>>>>> "Hannes" == Hannes Domani via Gdb-patches <gdb-patches@sourceware.org> writes:

Hannes> 2020-12-21  Hannes Domani  <ssbssa@yahoo.de>

Hannes> 	* tui/tui-winsource.c (tui_source_window_base::refresh_window):
Hannes> 	Call wnoutrefresh instead of tui_win_info::refresh_window.

Looks good.  Thank you.

Tom

Re: [PATCH 4/4] Prevent flickering when redrawing the TUI source window

[Christian Biesinger]

On Mon, Dec 21, 2020 at 3:24 PM Hannes Domani via Gdb-patches
<gdb-patches@sourceware.org> wrote:
>  tui_source_window_base::refresh_window ()
>  {
> -  tui_win_info::refresh_window ();
> +  wnoutrefresh (handle.get ());

Maybe it would be good to add a comment saying why you're calling
wnoutrefresh instead of the superclass? Or is this obvious anyway to
someone knowing ncurses?

Christian

Re: [PATCH 1/4] Fix TUI source window drawing

[Hannes Domani]

 Am Montag, 4. Januar 2021, 21:35:45 MEZ hat Tom Tromey <tom@tromey.com> Folgendes geschrieben:

> >>>>> "Hannes" == Hannes Domani via Gdb-patches <gdb-patches@sourceware.org> writes:
>
> Hannes> 2020-12-21  Hannes Domani  <ssbssa@yahoo.de>
>
> Hannes>     PR tui/26927
> Hannes>     * tui/tui-winsource.c (tui_source_window_base::refresh_window):
> Hannes>     Fix source pad size in prefresh.
> Hannes>     (tui_source_window_base::show_source_content): Grow source pad
> Hannes>     if necessary.
>
> Thank you for the patch.  This is ok.

Pushed, thanks.


Hannes

Re: [PATCH 2/4] Redraw both spaces between line numbers and source code

[Hannes Domani]

 Am Montag, 4. Januar 2021, 21:44:59 MEZ hat Tom Tromey <tom@tromey.com> Folgendes geschrieben:

> >>>>> "Hannes" == Hannes Domani via Gdb-patches <gdb-patches@sourceware.org> writes:
>
> Hannes> 2020-12-21  Hannes Domani  <ssbssa@yahoo.de>
>
> Hannes>     * tui/tui-source.c (tui_source_window::show_line_number):
> Hannes>     Redraw second space after line number.
>
> Thanks for the patch.
>
> Hannes> -  xsnprintf (text, sizeof (text), "%*d ", m_digits - 1, lineno);
> Hannes> +  xsnprintf (text, sizeof (text), "%*d  ", m_digits - 1, lineno);
>
> Would you mind adding a brief comment here explaining the need for two
> spaces?  I think that may prove useful in the future.  This is ok with
> this tweak.

Pushed with an added comment, thanks.


Hannes

Re: [PATCH 4/4] Prevent flickering when redrawing the TUI source window

[Hannes Domani]

 Am Montag, 4. Januar 2021, 21:55:28 MEZ hat Tom Tromey <tom@tromey.com> Folgendes geschrieben:

> >>>>> "Hannes" == Hannes Domani via Gdb-patches <gdb-patches@sourceware.org> writes:
>
> Hannes> 2020-12-21  Hannes Domani  <ssbssa@yahoo.de>
>
> Hannes>     * tui/tui-winsource.c (tui_source_window_base::refresh_window):
> Hannes>     Call wnoutrefresh instead of tui_win_info::refresh_window.
>
> Looks good.  Thank you.


Am Dienstag, 5. Januar 2021, 12:58:20 MEZ hat Christian Biesinger <cbiesinger@google.com> Folgendes geschrieben:

> Maybe it would be good to add a comment saying why you're calling
> wnoutrefresh instead of the superclass? Or is this obvious anyway to
> someone knowing ncurses?

Pushed with an added comment, thanks.


Hannes