- When both SC_PIXEL_MODE and SC_NO_FONT_LOADING are defined,
quietly drop SC_NO_FONT_LOADING, because the pixel(raster)
console requires font.
- When SC_NO_FONT_LOADING is defined, force SC_ALT_MOUSE_IMAGE.
Without font, the arrow-shaped mouse cursor cannot be drawn.
- Fiddle and simplify some internal macros.
MFC after: 2 weeks
Replace the a.out emulation of 'struct linker_set' with something
a little more flexible. <sys/linker_set.h> now provides macros for
accessing elements and completely hides the implementation.
The linker_set.h macros have been on the back burner in various
forms since 1998 and has ideas and code from Mike Smith (SET_FOREACH()),
John Polstra (ELF clue) and myself (cleaned up API and the conversion
of the rest of the kernel to use it).
The macros declare a strongly typed set. They return elements with the
type that you declare the set with, rather than a generic void *.
For ELF, we use the magic ld symbols (__start_<setname> and
__stop_<setname>). Thanks to Richard Henderson <rth@redhat.com> for the
trick about how to force ld to provide them for kld's.
For a.out, we use the old linker_set struct.
NOTE: the item lists are no longer null terminated. This is why
the code impact is high in certain areas.
The runtime linker has a new method to find the linker set
boundaries depending on which backend format is in use.
linker sets are still module/kld unfriendly and should never be used
for anything that may be modular one day.
Reviewed by: eivind
SC_DEV isn't NULL; if it is, evaluate to NULL and don't dereference
NULL. Callers of VIRTUAL_TTY must already check for the result being
NULL since si_tty can be NULL, so this should be safe.
This fixes a panic when trying to switch to a different vty in an
environment such as userconfig (-c option to the kernel).
PR: 26508
copies out the current contents of the video buffer for a syscons terminal,
providing a snapshot of the text and attributes.
Based heavily on work originally submitted by Joel Holveck <joelh@gnu.org>
for 2.2.x almost 30 months ago, which I cleaned up a little, and forward
ported to -current.
See also the usr.bin/scrshot utility.
other "system" header files.
Also help the deprecation of lockmgr.h by making it a sub-include of
sys/lock.h and removing sys/lockmgr.h form kernel .c files.
Sort sys/*.h includes where possible in affected files.
OK'ed by: bde (with reservations)
Paste always happens to current _text_ cursor position independently of
mouse cursor position in any case and old variant force user to press
mouse paste button _two_ times if mouse cursor is invisible.
cursor.
The reason is: mouse cursor goes into hide/visible loop while text cursor even
not moved.
PR: 25536
Submitted by: David Xu <davidx@viasoft.com.cn>
palette. As a result, the colors on the video console can look rather
weird. For example, sysinstall on the alpha has a read background. We
can work around this partially by remapping the colors used by syscons for
the ANSI color escape sequences. Note that screen savers and anything that
sets the colors explicitly will still get incorrect colors, but programs
such as sysinstall will now use the correct colors. A more correct fix
would be to actually fix the VGA palette on boot by either swapping all
the red and blue attributes or by hardcoding a standard palette and
overwriting the entire palette.
Requested by: gallatin
Obtained from: NetBSD
<sys/proc.h> to <sys/systm.h>.
Correctly document the #includes needed in the manpage.
Add one now needed #include of <sys/systm.h>.
Remove the consequent 48 unused #includes of <sys/proc.h>.
Replace all in-tree uses with <sys/mouse.h> which repo-copied a few
moments ago from src/sys/i386/include/mouse.h by peter.
This is also the appropriate fix for exo-tree sources.
Put warnings in <machine/mouse.h> to discourage use.
November 15th 2000 the warnings will be converted to errors.
January 15th 2001 the <machine/mouse.h> files will be removed.
Replace all in-tree uses with necessary subset of <sys/{fb,kb,cons}io.h>.
This is also the appropriate fix for exo-tree sources.
Put warnings in <machine/console.h> to discourage use.
November 15th 2000 the warnings will be converted to errors.
January 15th 2001 the <machine/console.h> files will be removed.
new location, all mouse events are harvested, not just the ones being
written out to moused(8). This means that mouse entropy is harvested
at the consoles as well as in X.
kernel can instigate an orderly shutdown but still determine the form of
that shutdown. Make it possible eg. to cleanly shutdown and power off the
system under ACPI when the power button is pressed.
the drivers.
* Remove legacy inx/outx support from chipset and replace with macros
which call busspace.
* Rework pci config accesses to route through the pcib device instead of
calling a MD function directly.
With these changes it is possible to cleanly support machines which have
more than one independantly numbered PCI busses. As a bonus, the new
busspace implementation should be measurably faster than the old one.
wrong bytes.
o Improve the public interface; use void* instead of char* or u_int64_t
to pass arbitrary data around.
Submitted by: kris ("horrible bug")
It may cause misterious chars appearse in the middle of the scrolled lines.
The bug trigger: enter
grep P_32 /usr/include/*.h
command and see misterious "db.\" filename.
won't appear on the screen, and "blinking" and "destructive" cursor
won't appear in the vty for which the text cursor is currently hidden.
Approved by: jkh
- Split terminal emulation code from the main part of the driver so
that we can have alternative terminal emulator modules if we like in
the future. (We are not quite there yet, though.)
- Put sysmouse related code in a separate file, thus, simplifying the
main part of the driver.
As some files are added to the source tree, you need to run config(8)
before you compile a new kernel next time.
You shouldn't see any functional change by this commit; this is only
internal code reorganization.
ddb is entered. Don't refer to `in_Debugger' to see if we
are in the debugger. (The variable used to be static in Debugger()
and wasn't updated if ddb is entered via traps and panic anyway.)
- Don't refer to `in_Debugger'.
- Add `db_active' to i386/i386/db_interface.d (as in
alpha/alpha/db_interface.c).
- Remove cnpollc() stub from ddb/db_input.c.
- Add the dbctl function to syscons, pcvt, and sio. (The function for
pcvt and sio is noop at the moment.)
Jointly developed by: bde and me
(The final version was tweaked by me and not reviewed by bde. Thus,
if there is any error in this commit, that is entirely of mine, not
his.)
Some changes were obtained from: NetBSD
keymap and pressed, the system panic will be forced.
This feature must be specifically enabled by a new sysctl variable:
machdep.enable_panic_key. Its default value is 0. The panic key
won't do anything unless this variable is set to non-zero.
To use the panic key, add a keyword 'panic' to a key in your
keymap file. The following example assigns the panic function
to SysReq (Alt-PrintScreen) key (keycode 84).
083 del '.' '.' '.' '.' '.' boot boot N
084 panic nop nop nop panic nop nop nop O
085 nop nop nop nop nop nop nop nop O
PR: kern/13721
X server, is not responding to the VT switching protocol. (This part
of the code has been somewhat wrong in -CURRENT, but -STABLE has the
correct code...)
apm_saver uses the apm_display() routine from the apm system to
"suspend" the "display" part of the machine.
This is beneficial for some laptops (or other machines with
non-traditional displays) that choke on the 'green' saver's
effect.
Another way of looking at this is that it's the same as a screen
saver that does an 'apm -d 0' to blank the display and an 'apm -d 1'
to bring it back. One probably ought to use these commands to make
sure the effect will be correct before using it unattended.
have been there in the first place. A GENERIC kernel shrinks almost 1k.
Add a slightly different safetybelt under nostop for tty drivers.
Add some missing FreeBSD tags
fields in struct cdevsw:
d_stop moved to struct tty.
d_reset already unused.
d_devtotty linkage now provided by dev_t->si_tty.
These fields will be removed from struct cdevsw together with
d_params and d_maxio Real Soon Now.
The changes in this patch consist of:
initialize dev->si_tty in *_open()
initialize tty->t_stop
remove devtotty functions
rename ttpoll to ttypoll
a few adjustments to these changes in the generic code
a bump of __FreeBSD_version
add a couple of FreeBSD tags
- Remove sc_get_scr_stat(). It's not necessary anymore.
- Call ttymalloc() to allocate the struct tty for each vty, rather than
statically declaring an array of struct tty. We still need a statically
allocated struct tty for the first vty which is used for the kernel
console I/O, though.
- Likewise, call ttymalloc() for /dev/sysmouse and /dev/consolectl.
- Delete unnecessary test on the pointer struct tty *tp in some functions.
- Delete unused code in scmouse.c.
WARNING: this change requires you to recompile screen savers!
Diskslice/label code not yet handled.
Vinum, i4b, alpha, pc98 not dealt with (left to respective Maintainers)
Add the correct hook for devfs to kern_conf.c
The net result of this excercise is that a lot less files depends on DEVFS,
and devtoname() gets more sensible output in many cases.
A few drivers had minor additional cleanups performed relating to cdevsw
registration.
A few drivers don't register a cdevsw{} anymore, but only use make_dev().
events, in order to pave the way for removing a number of the ad-hoc
implementations currently in use.
Retire the at_shutdown family of functions and replace them with
new event handler lists.
Rework kern_shutdown.c to take greater advantage of the use of event
handlers.
Reviewed by: green
- Correctly observe the variable `extra_history_size' when changing
the size of history (scroll back) buffer.
- Added sc_free_history_buffer().
Pointed out by: des
and insertion should affect the line the cursor is on only.
This change should have been committed together with syscons.c rev 1.308.
(I forgot to do so, when I committed syscons.c :-(
Pointed out by: sos
- Split syscons source code into manageable chunks and reorganize
some of complicated functions.
- Many static variables are moved to the softc structure.
- Added a new key function, PREV. When this key is pressed, the vty
immediately before the current vty will become foreground. Analogue
to PREV, which is usually assigned to the PrntScrn key.
PR: kern/10113
Submitted by: Christian Weisgerber <naddy@mips.rhein-neckar.de>
- Modified the kernel console input function sccngetc() so that it
handles function keys properly.
- Reorganized the screen update routine.
- VT switching code is reorganized. It now should be slightly more
robust than before.
- Added the DEVICE_RESUME function so that syscons no longer hooks the
APM resume event directly.
- New kernel configuration options: SC_NO_CUTPASTE, SC_NO_FONT_LOADING,
SC_NO_HISTORY and SC_NO_SYSMOUSE.
Various parts of syscons can be omitted so that the kernel size is
reduced.
SC_PIXEL_MODE
Made the VESA 800x600 mode an option, rather than a standard part of
syscons.
SC_DISABLE_DDBKEY
Disables the `debug' key combination.
SC_ALT_MOUSE_IMAGE
Inverse the character cell at the mouse cursor position in the text
console, rather than drawing an arrow on the screen.
Submitted by: Nick Hibma (n_hibma@FreeBSD.ORG)
SC_DFLT_FONT
makeoptions "SC_DFLT_FONT=_font_name_"
Include the named font as the default font of syscons. 16-line,
14-line and 8-line font data will be compiled in. This option replaces
the existing STD8X16FONT option, which loads 16-line font data only.
- The VGA driver is split into /sys/dev/fb/vga.c and /sys/isa/vga_isa.c.
- The video driver provides a set of ioctl commands to manipulate the
frame buffer.
- New kernel configuration option: VGA_WIDTH90
Enables 90 column modes: 90x25, 90x30, 90x43, 90x50, 90x60. These
modes are mot always supported by the video card.
PR: i386/7510
Submitted by: kbyanc@freedomnet.com and alexv@sui.gda.itesm.mx.
- The header file machine/console.h is reorganized; its contents is now
split into sys/fbio.h, sys/kbio.h (a new file) and sys/consio.h
(another new file). machine/console.h is still maintained for
compatibility reasons.
- Kernel console selection/installation routines are fixed and
slightly rebumped so that it should now be possible to switch between
the interanl kernel console (sc or vt) and a remote kernel console
(sio) again, as it was in 2.x, 3.0 and 3.1.
- Screen savers and splash screen decoders
Because of the header file reorganization described above, screen
savers and splash screen decoders are slightly modified. After this
update, /sys/modules/syscons/saver.h is no longer necessary and is
removed.
The cdevsw_add() function now finds the major number(s) in the
struct cdevsw passed to it. cdevsw_add_generic() is no longer
needed, cdevsw_add() does the same thing.
cdevsw_add() will print an message if the d_maj field looks bogus.
Remove nblkdev and nchrdev variables. Most places they were used
bogusly. Instead check a dev_t for validity by seeing if devsw()
or bdevsw() returns NULL.
Move bdevsw() and devsw() functions to kern/kern_conf.c
Bump __FreeBSD_version to 400006
This commit removes:
72 bogus makedev() calls
26 bogus SYSINIT functions
if_xe.c bogusly accessed cdevsw[], author/maintainer please fix.
I4b and vinum not changed. Patches emailed to authors. LINT
probably broken until they catch up.
Reformat and initialize correctly all "struct cdevsw".
Initialize the d_maj and d_bmaj fields.
The d_reset field was not removed, although it is never used.
I used a program to do most of this, so all the files now use the
same consistent format. Please keep it that way.
Vinum and i4b not modified, patches emailed to respective authors.
1:
s/suser/suser_xxx/
2:
Add new function: suser(struct proc *), prototyped in <sys/proc.h>.
3:
s/suser_xxx(\([a-zA-Z0-9_]*\)->p_ucred, \&\1->p_acflag)/suser(\1)/
The remaining suser_xxx() calls will be scrutinized and dealt with
later.
There may be some unneeded #include <sys/cred.h>, but they are left
as an exercise for Bruce.
More changes to the suser() API will come along with the "jail" code.
i386 platform boots, it is no longer ISA-centric, and is fully dynamic.
Most old drivers compile and run without modification via 'compatability
shims' to enable a smoother transition. eisa, isapnp and pccard* are
not yet using the new resource manager. Once fully converted, all drivers
will be loadable, including PCI and ISA.
(Some other changes appear to have snuck in, including a port of Soren's
ATA driver to the Alpha. Soren, back this out if you need to.)
This is a checkpoint of work-in-progress, but is quite functional.
The bulk of the work was done over the last few years by Doug Rabson and
Garrett Wollman.
Approved by: core
- Refined internal interface in keyboard drivers so that:
1. the side effect of device probe is kept minimal,
2. polling mode function is added,
3. and new ioctl and configuration options are added (see below).
- Added new ioctl: KDSETREPEAT
Set keyboard typematic rate. There has existed an ioctl command,
KDSETRAD, for the same purpose. However, KDSETRAD is dependent on
the AT keyboard. KDSETREPEAT provides more generic interface.
KDSETRAD will still be supported in the atkbd driver.
- Added new configuration options:
ATKBD_DFLT_KEYMAP
Specify a keymap to be used as the default, built-in keymap.
(There has been undocumented options, DKKEYMAP, UKKEYMAP, GRKEYMAP,
SWKEYMAP, RUKEYMAP, ESKEYMAP, and ISKEYMAP to set the default keymap.
These options are now gone for good. The new option is more general.)
KBD_DISABLE_KEYMAP_LOADING
Don't allow the user to change the keymap.
the screen width.
- Store the current video mode information in the `video_adapter' struct.
- The size of the `v_offscreensize' field in the VESA mode information
block is u_int16, not u_int8.
- Bring down the splash screen when a vty is opened for the first
time.
- Make sure the splash screen/screen saver is stopped before
switching vtys.
- Read and save initial values in the BIOS data area early.
VESA BIOS may change BIOS data values when switching modes.
- Fix missing '&' operator.
- Move ISA specific part of driver initialization to syscons_isa.c.
atkbd
- kbdtables.h is now in /sys/dev/kbd.
all
- Adjust for forthcoming alpha port. Submitted by: dfr
0 success
EAGAIN try again later
other don't call this screen saver again
- Test flags consistently to examine the status of the screen saver.
scrn_blanked: the screen saver is running
scp->status & SAVER_RUNNING: the saver is running in this vty
- Correctlyu preserve status flag bits in set/restore_scrn_saver_mdoe().
keyboard and video card drivers.
Because of the changes, you are required to update your kernel
configuration file now!
The files in sys/dev/syscons are still i386-specific (but less so than
before), and won't compile for alpha and PC98 yet.
syscons still directly accesses the video card registers here and
there; this will be rectified in the later stages.
from sc, vt and sio drivers. Use instead a linker_set to collect them.
Staticize ??cngetc(), ??cnputc(), etc functions in sc and vt drivers.
We must still have siocngetc() and siocnputc() as globals because they
are directly referred to by i386-gdbstub.c :-(
Oked by: bde
truncated to 32 bits.
* Change the calling convention of the device mmap entry point to
pass a vm_offset_t instead of an int for the offset allowing
devices with a larger memory map than (1<<32) to be supported
on the alpha (/dev/mem is one such).
These changes are required to allow the X server to mmap the various
I/O regions used for device port and memory access on the alpha.
- Express various sizes in bytes, rather than Kbytes, in the video
mode and adapter information structures.
- Fill 0 in the linear buffer size field if the linear frame buffer
is not available.
- Remove SW_VESA_USER ioctl. It is still experimetal and was not meant
to be released.
- Fix missing cast operator.
- Correctly handle pointers returned by the VESA BIOS. The pointers
may point to the area either in the BIOS ROM or in the buffer supplied
by the caller.
- Set the destructive cursor at the right moment.
- there were too many global variables (there still are :-).
- the data section was bloated by explicit initializations of static
variables to 0 (only fixed the recently changed ones).
- WRAPHIST() had silly parentheses around foo->bar.
- the comment about inline functions was stale.
- the comment about Userconfig presumes too much about the boot environment.
- `i' was reused confusingly in scioctl().
- the declaration of `butmap' used a deprecated K&R misfeature.
- the initializeation of `butmap' had an unnecessary line break.
- `unsigned char' was not consistently (mis)spelled as u_char.
- English was poor in a comment in videoio.c.
Submitted by: bde
- Handle pixel (raster text) mode properly.
- Clear screen and paint border right.
- Paint text attribute (colors).
- Fix off-by-one errors.
- Add some sanity checks.
- Fix some function prototypes.
- Add some comment lines.
- Define generic text mode numbers so that the user can just give
"80x25", "80x60", "132x25"..., rather than "VGA_xxx", to `vidcontrol'
to change the current video mode. `vidoio.c' and `vesa.c' will map
these numbers to real video mode numbers appropriate and available
with the given video hardware. I believe this will be useful to make
syscons more portable across archtectures.
Kazu writes:
The VESA support code requires vm86 support. Make sure your kernel
configuration file has the following line.
options "VM86"
If you want to statically link the VESA support code to the kernel,
add the following option to the kernel configuration file.
options "VESA"
The vidcontrol command now accepts the following video mode names:
VESA_132x25, VESA_132x43, VESA_132x50, VESA_132x60, VESA_800x600
The VESA_800x600 mode is a raster display mode. The 80x25 text will
be displayed on the 800x600 screen. Useful for some laptop computers.
vidcontrol accepts the new `-i <info>' option, where <info> must be
either `adapter' or `mode'. When the `-i adapter' option is given,
vidcontrol will print basic information (not much) on the video
adapter. When the `-i mode' option is specified, vidcontrol will
list video modes which are actually supported by the video adapter.
Submitted by: Kazutaka YOKOTA yokota@FreeBSD.ORG
for the Lite2 fix for always returning EIO in dead_read().
Cleaned up the cdevswitch initializers for all tty drivers.
Removed explicit calls to ttsetwater() from all (tty) drivers. ttsetwater()
is now called centrally for opens, not just for parameter changes.
chip.
It has been observed that the problem is most apparent:
a) in notebook computers,
b) and/or in the systems with C&T video chips.
Define the new configuration option SC_BAD_FLICKER in the kernel
configuration file to remove outb()/outw() calls in question.
saver and splash screen can all work properly with syscons. Note that
the splash screen option (SC_SPLASH_SCREEN) does not work yet, as it
requires additional code from msmith.
- Reorganized the splash screen code to match the latest development
in this area.
- Delay screen switch in `switch_scr()' until the screen saver is
stopped, if one is running,
- Start the screen saver immediately, if any, when the `saver' key is
pressed. (There will be another commit for `kbdcontrol' to support
this keyword in the keymap file.)
- Do not always stop the screen saver when mouse-related ioctls
are called. Stop it only if the mouse is moved or buttons are
clicked; don't stop it if any other mouse ioctls are called.
2. Added provision to write userland screen savers. (Contact me if you
are interested in writing one.)
- Added CONS_IDLE, CONS_SAVERMODE, and CONS_SAVERSTART ioctls to
support userland screen savers.
3. Some code clean-ups.
the screen mode is changed even if another vty has larger size.
Reallocate the buffer only when the new screen size is larger than
the current cut buffer size.
When bell is of "quiet" types, the console won't ring (or flush)
if the ringing process is in a background vty.
PR: i386/2853
- Modify the escape sequence 'ESC[=%d;%dB' so that bell pitch and
duration are set in hertz and msecs by kbdcontrol(1).
There will be a corresponding kbdcontrol patch.
PR: bin/6037
Submitted by: Kouichi Hirabayashi (kh@eve.mogami-wire.co.jp)
is the kernel part of my commits, the userlevel stuff will be done in
a separate commit. Add the ability to suspend as well as hibernate to
syscons. Create a new virtual key like hibernate for suspend. Update
apm_bios.h to define more apm bios goodies.
FreeBSD/alpha. The most significant item is to change the command
argument to ioctl functions from int to u_long. This change brings us
inline with various other BSD versions. Driver writers may like to
use (__FreeBSD_version == 300003) to detect this change.
The prototype FreeBSD/alpha machdep will follow in a couple of days
time.
- Set the correct value scp->font_size in init_scp().
- Set scp->font_size to FONT_NONE for VGA_MODEX.
Interim fix for a font problem:
- A kludge to display the correct font on some video cards.
We should be able to load multiple fonts to the VGA plane #2 and switch
between fonts by setting the font select register in the VGA sequencer.
It appears that the current code isn't functioning as expected on
some VGA cards (I have reports on Millenium and Mach64 cards). This is
either a bug in syscons or a hardware compatibility problem ;-<
This kludge will always load only one font set at a time and always use
the font page #0 on the plane #2. It is an interim kludge until
we find the exact cause and solution.
Small adjustment for mouse cursor handling:
- Turn off the mouse cursor early when changing video modes.
Video mode switch fixes:
- Stop the screen saver when changing video modes.
- Enclose the critical section with a pair of spltty()/splx().
- A kludge to prevent scrn_update() from accessing video memory in less-
critical sections in video mode change; artificially turn on the
UNKNOWN_MODE flag.
PR: bin/5899, bin/5907
Tested by: ache and a couple of users
OKed by: sos
* Figure out UTC relative to boottime. Four new functions provide
time relative to boottime.
* move "runtime" into struct proc. This helps fix the calcru()
problem in SMP.
* kill mono_time.
* add timespec{add|sub|cmp} macros to time.h. (XXX: These may change!)
* nanosleep, select & poll takes long sleeps one day at a time
Reviewed by: bde
Tested by: ache and others
this using option "-b" to the boot blocks. It is smartest to compile
a font into your kernel (See LINT), but not mandatory, but apart from
the cursor you will see nothing on the screen until you load a font.
This mode allows XF86_VGA16 to run in 800x600 mode on otherwise unsupported
graphics hardware.
A number of buglets in the cursor handling in syscons may become
visible this way.
mode switch in ioctl.
Possibly related to PR: kern/4271
- A kludge: initialize scp->xpixel and ypixel even in the text mode.
If the console enters the `unknown' graphics mode via the ioctl KDSETMODE
(KD_GRAPHICS), these fields are not set (because syscons cannot know
the correct values), but set_mouse_pos() need to refer to these field
to adjust the mouse position.
- Turn off MOUSE_VISIBLE when switching video mode by ioctl.
- another new option: SC_MOUSE_CHAR
Define the first character code of four consecutive codes to be used for
the mouse cursor. Default codes are 0xd0 through 0xd3. Beware that
if you decide to use any codes outside the range of 0xc0-0xdf,
the mouse cursor may not look good, because of the way VGA displays
characters in 9-dot-wide character cells.
Requested by several people.
(This patch was tested by a person who recently reported, in the -current
ML, a page fault problem in the kernel (draw_mouse_iamge()) after
X server shutdown. The patch cured his problem.)
Don't touch/update the screen while manipulating font data.
Possibly related to PR: kern/4271
- Set up VGA in alphanumeric mode rather than graphics mode when
loading font into video memory. This will drastically reduce flicker.
PR: bin/2977
- Set up scp->font_size properly during video mode switch caused by
ioctl.
separate routine: scupdate() called from scrn_timer().
- Make sure that the screen is updated for the low-level console
routines sccngetc() and sccncheckc(). A new routine, sccnupdate(),
is introduced and will call scupdate() above.
Requested by: bde and msmith
OKed by: sos
from the low-level console routines sccngetc() and sccncheckc().
Submitted by: bde (a long time ago)
- Don't try to ring bell and immediately return from do_bell() while
device probe is in progress at boot time; the timeout queue is not
functional yet.
PR: kern/2424
- Stop running the screen saver after panic() is called: check
if `panicstr' is non-NULL during scrn_timer().
PR: kern/5314
- A new option: SC_DISABLE_REBOOT
The reboot key (usually Ctl-Alt-Del) will be ignored if this option
is defined. You may still have the reboot key defined in the keymap and
it won't cause error when the keymap is loaded, but it will be quietly
treated as nop.
OKed by: sos
