JehanneOS/newlib
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

Fix buffer scrolling when performing a "clear screen"

Browse Source 
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
This commit is contained in:
Corinna Vinschen
2016-07-27 20:39:24 +02:00
parent 32b668d966
commit 08da3bfc41
1 changed files with 35 additions and 19 deletions
Download Patch File Download Diff File Expand all files Collapse all files

54
winsup/cygwin/fhandler_console.cc
View File

@@ -1216,30 +1216,46 @@ dev_console::scroll_window (HANDLE h, int x1, int y1, int x2, int y2)
return false;
SMALL_RECT sr;
int toscroll = 2 + dwEnd.Y - b.srWindow.Top;
int shrink = 1 + toscroll + b.srWindow.Bottom - b.dwSize.Y;
int toscroll = dwEnd.Y - b.srWindow.Top + 1;
sr.Left = sr.Right = dwEnd.X = 0;
/* Can't increment dwEnd yet since we may not have space in
the buffer. */
SetConsoleCursorPosition (h, dwEnd);
if (shrink > 0)
if (b.srWindow.Bottom + toscroll >= b.dwSize.Y)
{
COORD c = b.dwSize;
c.Y = dwEnd.Y - shrink;
SetConsoleScreenBufferSize (h, c);
SetConsoleScreenBufferSize (h, b.dwSize);
dwEnd.Y = 0;
fillin (h);
toscroll = 2 + dwEnd.Y - b.srWindow.Top;
/* So we're at the end of the buffer and scrolling the console window
would move us beyond the buffer. What we do here is to scroll the
console buffer upward by just as much so that the current last line
becomes the last line just prior to the first window line. That
keeps the end of the console buffer intact, as desired.
Since we're moving the console buffer under the console window in
this case, we must not move the console window. */
SMALL_RECT br;
COORD dest;
CHAR_INFO fill;
br.Left = 0;
br.Top = dwEnd.Y - b.srWindow.Top + 1;
br.Right = b.dwSize.X - 1;
br.Bottom = b.dwSize.Y - 1;
dest.X = dest.Y = 0;
fill.Char.AsciiChar = ' ';
fill.Attributes = current_win32_attr;
ScrollConsoleScreenBuffer (h, &br, NULL, dest, &fill);
/* Fix dwEnd to reflect the new cursor line (minus 1 to take the
increment a few lines later into account) */
dwEnd.Y = b.dwCursorPosition.Y - 1;
}
sr.Top = sr.Bottom = toscroll;
SetConsoleWindowInfo (h, FALSE, &sr);
else
{
/* The reminder of the console buffer is big enough to simply move
the console window. */
sr.Top = sr.Bottom = toscroll;
SetConsoleWindowInfo (h, FALSE, &sr);
}
/* Eventually set cursor to new end position at the top of the window. */
dwEnd.Y++;
SetConsoleCursorPosition (h, dwEnd);
/* Fix up console buffer info. */
fillin (h);
return true;
}