background is default (8), introduce an explicit free function and use
it where a free alone is needed. Likewise, use memmove directly rather
than grid_move_lines where it makes sense. Based on a memory leak fix by
Dan Aloni in GitHub issue 1051.
together instead of handling them one by one. This is significantly
faster. Sequences are terminated when we reach the end of the line, fill
the internal buffer, or a different character is seen by the input
parser (an escape sequence, or UTF-8).
Rather than writing collected sequences out immediately, hold them until
it is necessary (another screen modification, or we consume all
available data). This means we can discard changes that would have no
effect (for example, lines that would just be scrolled off the screen or
cleared). This reduces the total amount of data we write out to the
terminal - not important for fast terminals, but a big help with slow
(like xterm).
sequences (notable EL and ED but also IL, DL, ICH, DCH) create blank
cells using the current background colour rather than the default
colour.
On modern systems BCE doesn't really have many benefits, but most other
terminals now support it, some (lazy) applications rely on it, and it is
not hard to include now that we have pane background colours anyway.
Mostly written by Sean Haugh.
of storing a full grid_cell with UTF-8 data and everything, store a new
type grid_cell_entry. This can either be the cell itself (for ASCII
cells), or an offset into an extended array (per line) for UTF-8
data.
This avoid a large (8 byte) overhead on non-UTF-8 cells (by far the
majority for most users) without the complexity of the shadow array we
had before. Grid memory without any UTF-8 is about half.
The disadvantage that cells can no longer be modified in place and need
to be copied out of the grid and back but it turned out to be lot less
complicated than I expected.
- Don't extend the line to full width on insert/delete character which
means leaves extra spaces when reflowing.
- Only mark a line wrapped when the cursor actually goes off the end,
not on newlines which can be used for positioning.
screen interactive programs to preserve the screen contents. When activated, it
saves a copy of the visible grid and disables scrolling into and resizing out
of the history; when deactivated the visible data is restored and the history
reenabled.
of characters which may be inserted or deleted is the screen width, not one
less (and similarly for lines and height); and if characters or lines are
deleted by moving the ones that follow, the space at the end needs to be
cleared.
This appears to solve long-standing redraw issues most visible when using the
force-width option then scrolling in view(1) or unwrapping lines in emacs.
terminal to be switched between several different windows and programs
displayed on one terminal be detached from one terminal and moved to another.
ok deraadt pirofti
