As reported by several users on the mailing lists, applications like
screen(1) fail to properly handle ^S and ^Q characters. This was because
MPSAFE TTY didn't implement packet mode (TIOCPKT) yet. Add basic packet
mode support to make these applications work again.
Obtained from: //depot/projects/mpsafetty/...
Unlike pre-MPSAFE TTY, the pts(4) driver always returned ENXIO when a
read() or write() was performed on a pseudo-terminal master device when
the slave device was not opened. The old implementation had different
semantics:
- When the slave device had not been opened yet, read() and write() just
blocked.
- When the slave device had been closed, a read() call would return 0
bytes length.
- When the slave device had been closed, a write() call would return
EIO.
Change the new implementation to return 0 and EIO as well. We don't
implement the first rule, but I suspect this is not needed, because
routines like openpty() also open the slave device node. posix_openpt()
users also do similar things.
Reported by: rink
Tested by: rink
The last half year I've been working on a replacement TTY layer for the
FreeBSD kernel. The new TTY layer was designed to improve the following:
- Improved driver model:
The old TTY layer has a driver model that is not abstract enough to
make it friendly to use. A good example is the output path, where the
device drivers directly access the output buffers. This means that an
in-kernel PPP implementation must always convert network buffers into
TTY buffers.
If a PPP implementation would be built on top of the new TTY layer
(still needs a hooks layer, though), it would allow the PPP
implementation to directly hand the data to the TTY driver.
- Improved hotplugging:
With the old TTY layer, it isn't entirely safe to destroy TTY's from
the system. This implementation has a two-step destructing design,
where the driver first abandons the TTY. After all threads have left
the TTY, the TTY layer calls a routine in the driver, which can be
used to free resources (unit numbers, etc).
The pts(4) driver also implements this feature, which means
posix_openpt() will now return PTY's that are created on the fly.
- Improved performance:
One of the major improvements is the per-TTY mutex, which is expected
to improve scalability when compared to the old Giant locking.
Another change is the unbuffered copying to userspace, which is both
used on TTY device nodes and PTY masters.
Upgrading should be quite straightforward. Unlike previous versions,
existing kernel configuration files do not need to be changed, except
when they reference device drivers that are listed in UPDATING.
Obtained from: //depot/projects/mpsafetty/...
Approved by: philip (ex-mentor)
Discussed: on the lists, at BSDCan, at the DevSummit
Sponsored by: Snow B.V., the Netherlands
dcons(4) fixed by: kan
after each SYSINIT() macro invocation. This makes a number of
lightweight C parsers much happier with the FreeBSD kernel
source, including cflow's prcc and lxr.
MFC after: 1 month
Discussed with: imp, rink
Lock Giant in the clone handler.
Use destroy_dev_sched() explicitely from pty_maybecleanup() and postpone
pty_release() until both master and slave cdevs are destroyed by setting
it as callback for destroy_dev_sched().
Debugging help and testing by: Peter Holm
Approved by: re (kensmith)
- Sort by date in license blocks, oldest copyright first.
- All rights reserved after all copyrights, not just the first.
- Use (c) to be consistent with other entries.
MFC after: 3 days
specific privilege names to a broad range of privileges. These may
require some future tweaking.
Sponsored by: nCircle Network Security, Inc.
Obtained from: TrustedBSD Project
Discussed on: arch@
Reviewed (at least in part) by: mlaier, jmg, pjd, bde, ceri,
Alex Lyashkov <umka at sevcity dot net>,
Skip Ford <skip dot ford at verizon dot net>,
Antoine Brodin <antoine dot brodin at laposte dot net>
ioctls passing integer arguments should use the _IOWINT() macro.
This fixes a lot of ioctl's not working on sparc64, most notable
being keyboard/syscons ioctls.
Full ABI compatibility is provided, with the bonus of fixing the
handling of old ioctls on sparc64.
Reviewed by: bde (with contributions)
Tested by: emax, marius
MFC after: 1 week
this is more consistent with the placement of slaves in /dev/pts. The
actual name doesn't matter as it's not part of the exposed API or used by
libc. In some sense, it would be nice if these device nodes didn't have to
have names in devfs at all.
Suggested by: Stephen McKay <smckay at internode dot on dot net>
It should play nicely with the existing BSD ptys.
By default, the system will use the BSD ptys, one can set the sysctl
kern.pts.enable to 1 to make it use the new pts system.
The max number of pty that can be allocated on a system can be changed with the
sysctl kern.pts.max. It defaults to 1000, and can be increased, but it is not
recommanded, as any pty with a number > 999 won't be handled by whatever uses
utmp(5).
