* DevNotes: Add entry cgf-000026.

* fhandler.h (fhandler_console::save_top): Save top of screen coordinates.
* fhandler_console.cc (dev::save_restore): Record top of screen coordinates.
Clear entire buffer when restoring saved buffer and try to position the cursor
on the save relative place on the screen.

4 files changed, 27 insertions, 1 deletions

diff --git a/winsup/cygwin/ChangeLog b/winsup/cygwin/ChangeLog
index 5217a8510..383c252fd 100644
--- a/winsup/cygwin/ChangeLog
+++ b/winsup/cygwin/ChangeLog
@@ -1,3 +1,12 @@
+2014-04-26  Christopher Faylor  <me.cygwin2014@cgf.cx>
+
+	* DevNotes: Add entry cgf-000026.
+	* fhandler.h (fhandler_console::save_top): Save top of screen
+	coordinates.
+	* fhandler_console.cc (dev::save_restore): Record top of screen
+	coordinates.  Clear entire buffer when restoring saved buffer and try
+	to position the cursor on the save relative place on the screen.
+
 2014-04-25  Corinna Vinschen  <corinna@vinschen.de>
 
 	* syscalls.cc (NT_TRANSACTIONAL_ERROR): Cover all status codes up to
diff --git a/winsup/cygwin/DevNotes b/winsup/cygwin/DevNotes
index 0f480954a..5d31ed72e 100644
--- a/winsup/cygwin/DevNotes
+++ b/winsup/cygwin/DevNotes
@@ -1,3 +1,12 @@
+2014-04-26  cgf-000026
+
+Forgot to clear to the end of screen when restoring a screen buffer.
+That worked, for some reason, with Take Command but not with normal
+consoles.  I don't remember why I didn't resize the screen like a Linux
+X terminal emulator but that might have made things work a little
+better.  Right now, there is a scroll bar for apps like less or vi and
+that doesn't feel right.
+
 2014-03-29  cgf-000025
 
 Reorganized _cygtls::signal_debugger to avoid sending anything to the
diff --git a/winsup/cygwin/fhandler.h b/winsup/cygwin/fhandler.h
index c738071de..19f629124 100644
--- a/winsup/cygwin/fhandler.h
+++ b/winsup/cygwin/fhandler.h
@@ -1302,6 +1302,7 @@ class dev_console
   COORD save_bufsize;
   PCHAR_INFO save_buf;
   COORD save_cursor;
+  SHORT save_top;
 
   COORD dwLastCursorPosition;
   COORD dwMousePosition;	/* scroll-adjusted coord of mouse event */
diff --git a/winsup/cygwin/fhandler_console.cc b/winsup/cygwin/fhandler_console.cc
index 7a97fc461..27471581a 100644
--- a/winsup/cygwin/fhandler_console.cc
+++ b/winsup/cygwin/fhandler_console.cc
@@ -1466,6 +1466,7 @@ dev_console::save_restore (HANDLE h, char c)
       save_buf = (PCHAR_INFO) cmalloc_abort (HEAP_1_BUF, screen_size);
 
       save_cursor = b.dwCursorPosition;	/* Remember where we were. */
+      save_top = b.srWindow.Top;
 
       SMALL_RECT now = {};		/* Read the whole buffer */
       now.Bottom = save_bufsize.Y - 1;
@@ -1489,6 +1490,7 @@ dev_console::save_restore (HANDLE h, char c)
       now.Bottom = save_bufsize.Y - 1;
       now.Right = save_bufsize.X - 1;
       /* Restore whole buffer */
+      clear_screen (h, 0, 0, b.dwSize.X - 1, b.dwSize.Y - 1);
       BOOL res = WriteConsoleOutputW (h, save_buf, save_bufsize, cob, &now);
       if (!res)
 	debug_printf ("WriteConsoleOutputW failed, %E");
@@ -1496,9 +1498,14 @@ dev_console::save_restore (HANDLE h, char c)
       cfree (save_buf);
       save_buf = NULL;
 
+      cob.X = 0;
+      cob.Y = save_top;
+      /* Temporarily position at top of screen */
+      if (!SetConsoleCursorPosition (h, cob))
+	debug_printf ("SetConsoleCursorInfo(%p, cob) failed during restore, %E", h);
       /* Position where we were previously */
       if (!SetConsoleCursorPosition (h, save_cursor))
-	debug_printf ("SetConsoleCursorInfo(%p, ...) failed during restore, %E", h);
+	debug_printf ("SetConsoleCursorInfo(%p, save_cursor) failed during restore, %E", h);
       /* Get back correct version of buffer information */
       dwEnd.X = dwEnd.Y = 0;
       fillin (h);