Copy stable/9 to releng/9.3 as part of the 9.3-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

MFC r263885

o Add new vd_driver method to do bitblt with mask, named vd_maskbitbltchr.
o Move vd_bitbltchr vga's driver method to vd_maskbitbltchr.
o Implement new vd_bitbltchr method for vga driver. (It do single write for 8
pixels, have to be a bit faster).

Sponsored by: The FreeBSD Foundation

MFC 219886, 226100, 226111, 226341, 242529, 259015, 259016, 259019, 259049,
259071, 259102, 259110, 259129, 259130, 259178, 259179, 259203, 259221,
259261, 259532, 259615, 259650, 259651, 259667, 259680, 259727, 259761,
259772, 259776, 259777, 259830, 259882, 259915, 260160, 260449, 260450,
260688, 260888, 260953, 261269, 261547, 261551, 261552, 261553, 261585
o Merge vt(4) virtual terminal (a.k.a. newcons) to stable/9.
o Merge teken updates.
o Add few more tty methods required by vt(4).
o Update syscons(4) to work with fresh teken.

Sponsored by: The FreeBSD Foundation

Merge VT(9) project (a.k.a. newcons).

Reviewed by: nwhitehorn
MFC_to_10_after: re approval

Sponsored by: The FreeBSD Foundation

Notify terminal about process on current terminal start to use mouse on a
different "mouse level".

Sponsored by: The FreeBSD Foundation

Add VT_ALT_TO_ESC_HACK enabled by default. This will prepend ESC sequence before
any chars when any of ALT keys is down.
! Not sure if it right way, but now it is possible to use Alt keys in vim.

Sponsored by: The FreeBSD Foundation

Save last mouse event and check if the button1-up event happen w/o movement,
then ignore it. Otherwise such events broke double/triple click sequence.

Sponsored by: The FreeBSD Foundation

o Simplify POS_INDEX macro calculation.
o New macro POS_COPY to copy between term_pos_t.
o Add vtbuf_wth/vtbuf_htw helpers, to translate between screen coordinates and
circular history buffer location.
o Update vtbuf_iscursor to mark region selected by mouse.
o New helper vtbuf_flush_mark, to update regions where copy/paste mark changed.
o New method vtbuf_get_marked_len to get storage size for paste buffer.
o vtbuf_extract_marked fill (caller allocated buffer) with selected region data.
o Simplify mouse handler for copy/paste, and use vtbuf_flush_mark to update.
o New method vtbuf_scroll_mode, to help indicate Scroll mode by hiding cursor.
o Update header with new vtbuf methods.
o Add new vt_driver method vd_markedwin, to hold last window with selection.
o Enable paste support in core module.

Sponsored by: The FreeBSD Foundation
Pointed by: Claude Buisson <clbuisson@orange.fr> (Scroll mode indication)

Update vd_bitbltchr_t type to handle operation mask (to not touch pixels which
is not defined in mask) and bpl (bytes per source line).
Only vt_fb driver handle handle bpl yet.
Add protector for case when blitting image can be drawn partially out of screen,
like mouse cursor.

Mouse cursor and its movements works fine, copy/paste not yet.

Sponsored by: The FreeBSD Foundation

Define vt_mouse_event method.

Sponsored by: The FreeBSD Foundation

Use vtbuf_iscursor method instead of macro to get chars to display inverted.

Sponsored by: The FreeBSD Foundation

Add mouse related bits.

Sponsored by: The FreeBSD Foundation

Define marker support functions and type of markers.

Sponsored by: The FreeBSD Foundation

Add cut/paste region markers.

Sponsored by: The FreeBSD Foundation

Add mouse cursor format structure.

Sponsored by: The FreeBSD Foundation

Use opt_syscons.h to get defines.
Define max number of windows as VT_MAXWINDOWS if defined, or as MAXCONS, or 12.
Define VT_MOUSE_PASTEBUTTON and VT_MOUSE_EXTENDBUTTON if defined
SC_TWOBUTTON_MOUSE or VT_TWOBUTTON_MOUSE.

Sponsored by: The FreeBSD Foundation

Handle suspend/resume. Switch to console window before suspend, switch back on
resume. That fix issue with broken Xorg image after resume.
Fix some style whilst here.

Sponsored by: The FreeBSD Foundation

Define default size for early console to 640x480.

Sponsored by: The FreeBSD Foundation

Increase history size to 500 lines.

Sponsored by: The FreeBSD Foundation

Fix copyrights.

Sponsored by: The FreeBSD Foundation

o Mute keyboard input when ScrollLock mode is active.
o Simplify keys handling.
o Send ESC sequence for arrow keys in _cngetc, that will fix DDB history.

Sponsored by: The FreeBSD Foundation

Add new vt_buf flag VBF_HISTORY_FULL - whole history filled.

Sponsored by: The FreeBSD Foundation

Reverse priority. Bigger now better.

Sponsored by: The FreeBSD Foundation

o Rename bitblt method to bitbltchr, since it used to copy char with bg/fg colors
from font table, but not bitmap copy.
o Fix small mistake in comment.

Sponsored by: The FreeBSD Foundation

o Implement history buffer.
o Join history buffer with screen buffer. Same type of things.
o Reimplement buffer as an array of rows. Make it circular, so no overflow
tracking.
o Implement VT_PROCESS mode. Locking of VT switching by owner process.
o Add debug and deadtimer sysctls. deadtimer - defaulting to 15 seconds, time
to wait process answer in VT_PROCESS mode, to do VT switch in case when
process hang.
o Implement later console attach.
o Fix (partially yet) keyboard allocation.
o Add drivers priority. Disallow to replace KMS driver with VGA.
o Add ability to resize terminals.

Sponsored by: The FreeBSD Foundation

Readd the vt(4) driver and corresponding tools.