CVS log for src/sys/sys/signalvar.h

Up to [cvs.NetBSD.org] / src / sys / sys

Request diff between arbitrary revisions

Keyword substitution: kv
Default branch: MAIN

Use "stack_t" instead of "struct sigaltstack", as the former is the
newer standardized name.  NFC.

Sync w/ HEAD.

Separate the compat_netbsd32_coredump from the compat_netbsd32 and
coredump modules, into its own module.

Welcome to 7.99.75 !!!

Introduce new ptrace(2) operations: PT_SET_SIGPASS and PT_GET_SIGPASS

They deliver the logic of bypassing selected signals directly to the
debuggee, without informing the debugger.

This can be used to implement the QPassSignals GDB/LLDB protocol.

This call can be useful to avoid signal races in ATF ptrace tests.

Mostly merge changes from HEAD upto 20200411

- Untangle spawn_return by splitting it up to sub-functions.
- Merge the eventswitch parent notification code which was copied in two
  places (eventswitchchild)
- Fix bugs in the eventswitch parent notification code:
  1. p_slflags should be accessed holding both proc_lock and p->p_lock
  2. p->p_opptr can be NULL if the parent was PSL_CHTRACED and exited.

Fixes random crashes the posix_spawn_kill_spawner unit test which tried
to dereference a NULL pptr.

Move all non-emulation-specific coredump code into the coredump module,
and remove all #ifdef COREDUMP conditional compilation.  Now, the
coredump module is completely separated from the emulation modules, and
they can all be independently loaded and unloaded.

Welcome to 9.99.18 !

Pull up following revision(s) (requested by pgoyette in ticket #413):

	sys/kern/kern_core.c: revision 1.27 (patch)
	sys/kern/kern_sig.c: revision 1.377 (patch)
	sys/kern/kern_sig.c: revision 1.378 (patch)
	sys/kern/sys_sig.c: revision 1.50
	sys/kern/sys_ptrace_common.c: revision 1.70
	sys/kern/compat_stub.c: revision 1.16
	sys/compat/common/kern_sig_16.c: revision 1.4
	sys/kern/compat_stub.c: revision 1.17
	sys/sys/compat_stub.h: revision 1.20
	sys/sys/signalvar.h: revision 1.98
	sys/sys/compat_stub.h: revision 1.21
	sys/sys/signalvar.h: revision 1.99

Convert the sendsig_sigcontext_16 function pointer to use the new
compat_hook mechanism.
XXX Despite being a kernel<-->module abi change, this should be
XXX pulled up to -9

 -

Convert the coredump_vec modular function pointer to use the new
compat_hook mechanism.
XXX Should be pulled up to -9 despite the kernel <--> module ABI
XXX change.

Convert the coredump_vec modular function pointer to use the new
compat_hook mechanism.

XXX Should be pulled up to -9 despite the kernel <--> module ABI
XXX change.

Convert the sendsig_sigcontext_16 function pointer to use the new
compat_hook mechanism.

XXX Despite being a kernel<-->module abi change, this should be
XXX pulled up to -9

Pull up following revision(s) (requested by maxv in ticket #353):

	sys/kern/sys_sig.c: revision 1.48
	sys/sys/signalvar.h: revision 1.94
	sys/sys/signalvar.h: revision 1.95

Introduce sigaction_copy(), to copy sigaction structures without padding,
and use it in sigaction1(). This is to fix info leaks all at once in the
signal functions.

 -

Fix libkvm build.

Pull up following revision(s) (requested by kamil in ticket #328):

	sys/kern/kern_sig.c: revision 1.369
	sys/sys/signalvar.h: revision 1.97

Refactor sigswitch()

Make the function static as it is now local to kern_sig.c.
Rename the 'relock' argument to 'proc_lock_held' as it is more verbose.

This was suggested by mjg@freebsd. While there this flips the users between
true<->false.

Add additional KASSERT(9) calls here to validate whethe proc_lock is used
accordingly.

Pull up following revision(s) (requested by kamil in ticket #311):

	sys/sys/siginfo.h: revision 1.34
	sys/kern/sys_ptrace_common.c: revision 1.59
	sys/kern/sys_lwp.c: revision 1.70
	sys/compat/sys/siginfo.h: revision 1.8
	sys/kern/kern_sig.c: revision 1.365
	sys/kern/kern_lwp.c: revision 1.203
	sys/sys/signalvar.h: revision 1.96
	sys/kern/kern_exec.c: revision 1.482
	sys/kern/kern_fork.c: revision 1.214

Move TRAP_CHLD/TRAP_LWP ptrace information from struct proc to siginfo

Storing struct ptrace_state information inside struct proc was vulnerable
to synchronization bugs, as multiple events emitted in the same time were
overwritting other ones.

Cache the original parent process id in p_oppid. Reusing here p_opptr is
in theory prone to slight race codition.

Change the semantics of PT_GET_PROCESS_STATE, reutning EINVAL for calls
prompting for the value in cases when there wasn't registered an
appropriate event.

Add an alternative approach to check the ptrace_state information, directly
from the siginfo_t value returned from PT_GET_SIGINFO. The original
PT_GET_PROCESS_STATE approach is kept for compat with older NetBSD and
OpenBSD. New code is recommended to keep using PT_GET_PROCESS_STATE.
Add a couple of compile-time asserts for assumptions in the code.

No functional change intended in existing ptrace(2) software.

All ATF ptrace(2) and ATF GDB tests pass.

This change improves reliability of the threading ptrace(2) code.

Refactor sigswitch()

Make the function static as it is now local to kern_sig.c.

Rename the 'relock' argument to 'proc_lock_held' as it is more verbose.
This was suggested by mjg@freebsd. While there this flips the users between
true<->false.

Add additional KASSERT(9) calls here to validate whethe proc_lock is used
accordingly.

Move TRAP_CHLD/TRAP_LWP ptrace information from struct proc to siginfo

Storing struct ptrace_state information inside struct proc was vulnerable
to synchronization bugs, as multiple events emitted in the same time were
overwritting other ones.

Cache the original parent process id in p_oppid. Reusing here p_opptr is
in theory prone to slight race codition.

Change the semantics of PT_GET_PROCESS_STATE, reutning EINVAL for calls
prompting for the value in cases when there wasn't registered an
appropriate event.

Add an alternative approach to check the ptrace_state information, directly
from the siginfo_t value returned from PT_GET_SIGINFO. The original
PT_GET_PROCESS_STATE approach is kept for compat with older NetBSD and
OpenBSD. New code is recommended to keep using PT_GET_PROCESS_STATE.

Add a couple of compile-time asserts for assumptions in the code.

No functional change intended in existing ptrace(2) software.

All ATF ptrace(2) and ATF GDB tests pass.

This change improves reliability of the threading ptrace(2) code.

Fix libkvm build.

Introduce sigaction_copy(), to copy sigaction structures without padding,
and use it in sigaction1(). This is to fix info leaks all at once in the
signal functions.

Sync with HEAD

Register KTR events for debugger related signals

Register signals for:

 - crashes (FPE, SEGV, FPE, ILL, BUS)
 - LWP events
 - CHLD (FORK/VFORK/VFORK_DONE) events -- temporarily disabled
 - EXEC events

While there refactor related functions in order to simplify the code.

Add missing comment documentation for recently added kernel functions.

Add eventswitch() in signal code

Route all crash and debugger related signal through eventswitch(), that
calls sigswitch() with preprocessed arguments.

This code avoids code duplication and allows to introduce changes that
will affect all callers of sigswitch() in debugger-related events.

No functional change intended.

Sync with HEAD

Make stopsigmask a non-static symbol now as it's used in ptrace(2) code

This is a missing part of the previous commit.

While there fix a typo in a newly added comment in the ptrace(2) code.

Sponsored by <The NetBSD Foundation>

Synch with HEAD

Implement PTRACE_VFORK

Add support for tracing vfork(2) events in the context of ptrace(2).

This API covers other frontends to fork1(9) like posix_spawn(2) or clone(2),
if they cause parent to wait for exec(2) or exit(2) of the child.

Changes:
 - Add new argument to sigswitch() determining whether we need to acquire
   the proc_lock or whether it's already held.
 - Refactor fork1(9) for fork(2) and vfork(2)-like events.
   Call sigswitch() from fork(1) for forking or vforking parent, instead of
   emitting kpsignal(9). We need to emit the signal and suspend the parent,
   returning to user and relock proc_lock.
 - Add missing prototype for proc_stop_done() in kern_sig.c.
 - Make sigswitch a public function accessible from other kernel code
   including <sys/signalvar.h>.
 - Remove an entry about unimplemented PTRACE_VFORK in the ptrace(2) man page.
 - Permin PTRACE_VFORK in the ptrace(2) frontend for userland.
 - Remove expected failure for unimplemented PTRACE_VFORK tests in the ATF
   ptrace(2) test-suite.
 - Relax signal routing constraints under a debugger for a vfork(2)ed child.
   This intended to protect from signaling a parent of a vfork(2)ed child that
   called PT_TRACE_ME, but wrongly misrouted other signals in vfork(2)
   use-cases.

Add XXX comments about still existing problems and future enhancements:
 - correct vfork(2) + PT_TRACE_ME handling.
 - fork1(2) handling of scenarios when a process is collected in valid but
   rare cases.

All ATF ptrace(2) fork[1-8] and vfork[1-8] tests pass.

Fix PR kern/51630 by Kamil Rytarowski (myself).

Sponsored by <The NetBSD Foundation>

Sync with HEAD

s/static inline/static __inline/g for consistency with other include
headers.

update from HEAD

Sync with HEAD

Sync with HEAD.  (Note that most of these changes are simply $NetBSD$
tag issues.)

Introduce new ptrace(2) interface: PT_SET_SIGINFO and PT_GET_SIGINFO

This interface is designed to read signal information emited to tracee and
fake this signal with new value.

This functionality is required to distinguish types of events that occured
in the tracee and intercepted by a debugger.

These accessors introduce a new structure type ptrace_siginfo:
/*
 * Signal Information structure
 */
typedef struct ptrace_siginfo {
       siginfo_t       psi_siginfo;    /* signal information structure */
       lwpid_t         psi_lwpid;      /* destination LWP of the signal
                                        * value 0 means the whole process
                                        * (route signal to all LWPs) */
} ptrace_siginfo_t;

Include <sys/siginfo.h> in <sys/ptrace.h> in order to not break existing
software due to unknown symbol siginfo_t.

This interface has been proposed to the tech-kern@ mailing list.

Sponsored by <The NetBSD Foundation>

Sync with HEAD

Sync with HEAD

Realtime signal support from GSoC 2016, Charles Cui.

Rebase to HEAD as of a few days ago.

Rebase.

sync with head.

for a reference, the tree before this commit was tagged
as yamt-pagecache-tag8.

this commit was splitted into small chunks to avoid
a limitation of cvs.  ("Protocol error: too many arguments")

sync with head

sigexit() calls either exit1() or panic() and never returns.  Mark it as
__dead.

Change the type of the 'cookie' that holds the state of the core dump file
from 'void *' to the actual type 'struct coredump_iostate *'.
In most of the code the contents of the structure are still unknown.
This just stops the wrong type of pointer being passed to the 'void *'
parameter.
I hope I've found everything, amd64 GENERIC and i386 GENERIC & ALL compile.

convert vmem, signals, powerhooks from CIRCLEQ -> TAILQ.

sync with head

sync to -current.

Remove COMPAT_SA / KERN_SA.  Welcome to 6.99.3!
Approved by core@.

add a copyin function for sigset so that we can use sigtimedwait1 from
emulations.

Sync with HEAD.

sync with head

If a signal did not fire, restore the original signal mask for pselect/pollts
using a signal mask. Tested by tron.

PR/43625: Mark Davies: Fix pselect(2) to honor the temporary mask. pselect(2)
(and pollts(2)) are similar to sigsuspend(2) in that they temporarily change
the process signal mask and wait for signal delivery. Factor out and share the
code that does this.

Make stopsigmask static, sprinkle __cacheline_aligned and __read_mostly.

sync with head

Retire struct user, remove sys/user.h inclusions.  Note sys/user.h header
as obsolete.  Remove USER_TO_UAREA/UAREA_TO_USER macros.

Various #include fixes and review by matt@.

Sync with HEAD.

sync with head.

sync with head

Remove gsignal() and kgsignal() that do not prototype anything any more.

sync with head

Get rid of last "easy" kernel symbols starting with __:
__assert -> kern_assert
__sigtimedwait1 -> sigtimedwait1
__wdstart -> wdstart1

The rest are MD and/or shared with userspace, so they will require
a little more involvement than what is available for this quick
"ride the 5.99.24 bump" action.

sync with head.

Sync with HEAD.

Sync with HEAD.

merge christos-time_t

Update haad-dm branch to haad-dm-base2.

merge with head.

Make the emulations, exec formats, coredump, NFS, and the NFS server
into modules. By and large this commit:

- shuffles header files and ifdefs
- splits code out where necessary to be modular
- adds module glue for each of the components
- adds/replaces hooks for things that can be installed at runtime

Welcome to the time_t=long long dev_t=uint64_t branch.

sync with HEAD

sync with head.

constify

g/c CLRSIG

Sync with HEAD.

sync with head

sync with HEAD

Sync with HEAD

Start detangling lock.h from intr.h. This is likely to cause short term
breakage, but the mess of dependencies has been regularly breaking the
build recently anyhow.

Sync with HEAD

Sync with head.

Convert all the system call entry points from:
    int foo(struct lwp *l, void *v, register_t *retval)
to:
    int foo(struct lwp *l, const struct foo_args *uap, register_t *retval)
Fixup compat code to not write into 'uap' and (in some cases) to actually
pass a correctly formatted 'uap' structure with the right name to the
next routine.
A few 'compat' routines that just call standard ones have been deleted.
All the 'compat' code compiles (along with the kernels required to test
build it).
98% done by automated scripts.

sync with head.

Merge newlock2 to head.

- When clearing signals dequeue siginfo first and free later, once
  outside the lock permiter.
- Push kernel_lock back in a a couple of places.
- Adjust limcopy() to be MP safe (this needs redoing).
- Fix a couple of bugs noticed along the way.
- Catch up with condvar changes.

- Have callers to mi_switch() drop the kernel lock.
- Fix a deadlock and some typos.
- Unbreak ptrace().

sync with head.

Checkpoint work in progress.

sync with head.

Checkpoint work in progress.

kill signal "dolock" hacks.

related to PR/32962 and PR/34895.  reviewed by matthew green.

kill sched_psignal.
related to PR/32962 and PR/34895.  reviewed by matthew green.

- Redo LWP locking slightly and fix some races.
- Fix some locking botches.
- Make signal mask / stack per-proc for SA processes.
- Add _lwp_kill().

Checkpoint work in progress on locking and per-LWP signals. Very much a
a work in progress and there is still a lot to do.

sync with head

sync with head

Use the LWP cached credentials where sane.

sync with head.

Sync with head.

Merge 2006-05-24 NetBSD-current into the "peter-altq" branch.

sync with head.

integrate kauth.

- Move kauth_cred_t declaration to <sys/types.h>
- Cleanup struct ucred; forward declarations that are unused.
- Don't include <sys/kauth.h> in any header, but include it in the c files
  that need it.

Approved by core.

Sync with head.

sync with head.

From my posting of April 3 to tech-kern:

My understanding is that the CLRSIG() is supposed to clear the signal
that was sent to the syncer process to prevent it from being delivered
to the syncer process in case unmounting fails, so that the syncer process
does not die while the filesystem is still mounted. The typical scenario
is, the syncher process is tsleep()ing in the kernel, and waking up when
it needs to do work. If someone sends a signal to it, eg. kill -TERM
the mfs process, then the kernel will try to unmount the mfs filesystem
before delivering the signal to the process. If that unmount fails, then
we should not really kill the process because that will hang the mount.
So we call CLRSIG() to stop the signal from being delivered.

So the first call to issignal() will return the signal number that was
sent to the syncer process (unless someone malicious was able to send
a lower numbered signal between the time tsleep() returned and we called
issignal()... something that is not really easy to do). But you are
right, we should not be calling it many times as a side effect of this
macro.

Rewrite CLRSIG() clear all the signals and call issignal() the correct
number of times.

file signalvar.h was added on branch yamt-pdpolicy on 2006-05-24 10:59:21 +0000

implement PT_SYSCALL

merge ktrace-lwp.

Sync with HEAD. Here we go again...

sync with head

Only include sys/systm.h under _KERNEL, otherwise it needlessly pollutes
namespace, as shown by libkvm failing to compile for shadowing one of the
variables listed in sys/systm.h.  Reported by xtraeme@.

Implement a few changes needed to properly resolve PR#30924, as
discussed in the PR.

- introduce sys/timevar.h to hold kernel-specific stuff relevant to
  sys/time.h.  Ideally, timevar.h would contain all (or almost) of the
  #ifdef _KERNEL part of time.h, but that's a pretty big and tedious
  change to make.  For now, it will contain only the prototypes I
  introduced when working on COMPAT_NETBSD32.

- split copyinout_t into copyin_t and copyout_t, it makes prototypes more
  explicit about the meaning of a given argument.  Suggested by yamt@.

- move copyinout_t definition in sys/time.h to systm.h as copyin_t and
  copyout_t

- make everything uses the new types and include the proper headers at
  the proper places.

Pull up following revision(s) (requested by chs in ticket #901):
	sys/kern/kern_time.c: revision 1.94
	sys/sys/signalvar.h: revision 1.59
	sys/sys/savar.h: revision 1.16
	sys/kern/kern_sig.c: revision 1.209
	sys/kern/kern_sa.c: revision 1.66
	sys/kern/kern_synch.c: revision 1.150
avoid calling into the pool code while holding sched_lock
since both pool_get() and pool_put() can call wakeup().
instead, allocate the struct sadata_upcall before taking
sched_lock in mi_switch() and free it after releasing sched_lock.
clean up some modularity warts by adding a callback to
struct sadata_upcall for freeing sa_arg.

avoid calling into the pool code while holding sched_lock
since both pool_get() and pool_put() can call wakeup().
instead, allocate the struct sadata_upcall before taking
sched_lock in mi_switch() and free it after releasing sched_lock.

clean up some modularity warts by adding a callback to
struct sadata_upcall for freeing sa_arg.

compat code reorg.

Introduce __sigtimedwait1 which will help adding COMPAT_NETBSD32 support
for __sigtimedwait(2).

move misplaced endif.

Rework the coredump code to have no explicit knownledge of how coredump
i/o is done.  Instead, pass an opaque cookie which is then passed to a
new routine, coredump_write, which does the actual i/o.  This allows the
method of doing i/o to change without affecting any future MD code.
Also, make netbsd32_core.c [re]use core_netbsd.c (in a similar manner that
core_elf64.c uses core_elf32.c) and eliminate that code duplication.
cpu_coredump{,32} is now called twice, first with a NULL iocookie to fill
the core structure and a second to actually write md parts of the coredump.
All i/o is nolonger random access and is suitable for shipping over a stream.

sync with -current

sync with head.

Sync with HEAD.

de-__P

Sync with HEAD.

now takes an optional filename.

Fix the sync with head I botched.

Sync with HEAD.

Sync with HEAD

Change sigactsfree() to take a `struct sigacts' pointer, to fit the needs
of exit1 (its only client).

all ports define __HAVE_SIGINFO now, so remove the CPP conditionals

Gah, ksiginfo_t isn't actually exported to userland, so use
"struct ksiginfo *" instead.

XXX This is necessary because of <sys/sysctl.h> needed <sys/proc.h>; we
XXX need to clean up these headers!

Include <sys/siginfo.h> so we have the defn of ksiginfo_t.

modify sigtimedwait(2) to return full siginfo if available, and pass the wait
set using a pointer, to save couple bytes in struct sigctx

also fix fallout from recent lwp_wakeup() change, where we failed to properly
detect if tsleep() returned as result of lwp_wakeup() or signal outside
our wait set; could have caused problems for threaded apps using sigwait(2)
et.al.

Deal with signal trampoline being const.

Fix "constify sendsig/trapsignal" fallout for non-siginfo'd archs.  Test
compiled on most architectures.

constify sendsig/trapsignal [suggested by gimpy]

convert to use <queue.h> and add a lock for siginfo circleq.
XXX: could use STAILQ, but there is no way to remove an element without
rescanning the queue. We should really add a special iterator that can
do this.

handle deferred signal delivery with siginfo. struct sigctx changed, so
bump to ZB.

SA_SIGINFO changes. This is 1.5Z

Move UCB-licensed code from 4-clause to 3-clause licence.

Patches provided by Joel Baker in PR 22364, verified by myself.

prototype must not have variable name

Track the LWP ID of a synchronous (trap) signal, and report it in core dumps.

add __sigtimedwait(2) - wait for specified set of signals, with optional
timeout
the semantics of 'timeout' parameter differ to POSIX for the syscall
(not const, may be modified by kernel if interrupted from the wait) -
libc will provide appropriate wrapper

since sigwaitinfo(2) will be implemented as wrapper around sigtimedwait()
too, remove it's reserved slot and move sigqueue slot 'up', freeing
slot #246

Merge the nathanw_sa branch.

Sync with HEAD.

Move SIG_HOLD from <sys/signalvar.h> to <sys/signal.h>, since POSIX-2001
wants that name to be exposed.

Sync with HEAD.

Move declartion of SIGPROP to outside of multiple inclusion protection.
If _KERNEL is defined and SIGPROP is not defined, define sigprop as an
extern.

Adapt to changed psendsig() signature.

sync kqueue branch with HEAD

catch up with -current.

Catch up to -current.

Make killproc really public, and while we are there, constify.

catch up with -current.

Add kernel support for having userland provide the signal trampoline:

* struct sigacts gets a new sigact_sigdesc structure, which has the
  sigaction and the trampoline/version.  Version 0 means "legacy kernel
  provided trampoline".  Other versions are coordinated with machine-
  dependent code in libc.
* sigaction1() grows two more arguments -- the trampoline pointer and
  the trampoline version.
* A new __sigaction_sigtramp() system call is provided to register a
  trampoline along with a signal handler.
* The handler is no longer passed to sensig() functions.  Instead,
  sendsig() looks up the handler by peeking in the sigacts for the
  process getting the signal (since it has to look in there for the
  trampoline anyway).
* Native sendsig() functions now select the appropriate trampoline and
  its arguments based on the trampoline version in the sigacts.

Changes to libc to use the new facility will be checked in later.  Kernel
version not bumped; we will ride the 1.6C bump made recently.

catch up with -current on kqueue branch

Catch up to -current.
(CVS: It's not just a program. It's an adventure!)

- Define SIGRTMIN and SIGRTMAX iff _KERNEL.
- Bump the number of signals to 64, and define the default action for
  signals >= SIGRTMIN to be kill.

Sync kqueue branch with -current.

Catch up to -current.

Make the coredump routine exec-format/emulation specific.  Split
out traditional NetBSD coredump routines into core_netbsd.c and
netbsd32_core.c (for COMPAT_NETBSD32).

Add psendsignal().

Catch up to -current.

add an extern for the coredump32 hook.

remove some lint

Initial commit of scheduler activations and lightweight process support.

Sync with head (for UBC+NFS fixes, mostly).

Whenever ps_sigcheck is set to true, signotify() the process, and
wrap this all up in a CHECKSIGS() macro.  Also, in psignal1(),
signotify() SRUN and SIDL processes if __HAVE_AST_PERPROC is defined.

Per discussion w/ mycroft.

Sync with HEAD

split off thread specific stuff from struct sigacts to struct sigctx, leaving
    only signal handler array sharable between threads
move other random signal stuff from struct proc to struct sigctx

This addresses kern/10981 by Matthew Orgass.

Sync with HEAD.

Update thorpej_scsipi to -current as of a month ago

introduce SIGACTION_PS() macro - this is similar to SIGACTION(), but works
for (struct sigacts *) instead of (struct proc *)

add new function sigismasked(), which checks whether passed signal
is ignored or masked by the process, and use it appropriately
instead of directly checking p->p_sigmask and p->p_sigignore

Add a lock around the scheduler, and use it as necessary, including
in the non-MULTIPROCESSOR case (LOCKDEBUG requires it).  Scheduler
lock is held upon entry to mi_switch() and cpu_switch(), and
cpu_switch() releases the lock before returning.

Largely from Bill Sommerfeld, with some minor bug fixes and
machine-dependent code hacking from me.

Add prototype for cpu_coredump32()

Sync w/ -current.

Pull signal actions out of struct user, make them a separate proc
substructure, and allow them to be shared.

Required for clone(2).

Make contsigmask, stopsigmask, sigcantmask kernel private.

Put the prototypes for native_sig*_to_sig*() in one place.

Substantial signal handling changes:
* Increase the size of sigset_t to accomodate 128 signals -- adding new
  versions of sys_setprocmask(), sys_sigaction(), sys_sigpending() and
  sys_sigsuspend() to handle the changed arguments.
* Abstract the guts of sys_sigaltstack(), sys_setprocmask(), sys_sigaction(),
  sys_sigpending() and sys_sigsuspend() into separate functions, and call them
  from all the emulations rather than hard-coding everything.  (Avoids uses
  the stackgap crap for these system calls.)
* Add a new flag (p_checksig) to indicate that a process may have signals
  pending and userret() needs to do the full (slow) check.
* Eliminate SAS_ALTSTACK; it's exactly the inverse of SS_DISABLE.
* Correct emulation bugs with restoring SS_ONSTACK.
* Make the signal mask in the sigcontext always use the emulated mask format.
* Store signals internally in sigaction structures, rather than maintaining a
  bunch of little sigsets for each SA_* bit.
* Keep track of where we put the signal trampoline, rather than figuring it out
  in *_sendsig().
* Issue a warning when a non-emulated sigaction bit is observed.
* Add missing emulated signals, and a native SIGPWR (currently not used).
* Implement the `not reset when caught' semantics for relevant signals.

Note: Only code touched by the i386 port has been modified.  Other ports and
emulations need to be updated.

Merge with Lite2 + local changes

Import 4.4BSD-Lite2

Import 4.4BSD-Lite for reference

Significantly restructure the way signal state for a process is stored.
Rather than using bitmasks to redundantly store the information kept
in the process's sigacts (because the sigacts was kept in the u-area),
hang sigacts directly off the process, and access it directly.

Simplify signal setup code tremendously by storing information in
the sigacts as an array of struct sigactions, rather than in a different
format, since userspace uses sigactions.

Make sigacts sharable by adding reference counting.

add prototypes from <sys/cpu.h> to the appropriate places

Filesystem prototype changes

Fix some missing/wrong prototypes so that kern/* compiles again

Add ps_sigreset, to to keep track of signals which are reset when caught.

KERNEL -> _KERNEL

 code is an unsigned long, not an unsigned int.

New RCS ID's, take two.  they're more aesthecially pleasant, and use 'NetBSD'

new standard, minimally intrusive ID format

one-liner struct name change

lots of changes: prototype migration, move lots of variables, definitions,
and structure elements around.  kill some unnecessary type and macro
definitions.  standardize clock handling.  More changes than you'd want.

Rename a lot of process flags.

Make procfs really work for debugging.
Implement not & notepg files in procfs.

comments need ... '/'s at the end of them!!!

from HEAD:
add ps_usertramp to to struct sigacts.
SunOS compatibility; libc sigtramp

add ps_usertramp to to struct sigacts.
SunOS compatibility; libc sigtramp

add rcs ids as necessary, and also clean up headers

Add consistent multiple-inclusion protection.

initial import of 386bsd-0.1 sources

Initial revision