sys: Remove ancient SCCS tags.

Remove ancient SCCS tags from the tree, automated scripting, with two
minor fixup to keep things compiling. All the common forms in the tree
were removed with a perl script.

Sponsored by: Netflix

sys: Remove $FreeBSD$: one-line .h pattern

Remove /^\s*\*+\s*\$FreeBSD\$.*$\n/

sys: clean up empty lines in .c and .h files

sys: further adoption of SPDX licensing ID tags.

Mainly focus on files that use BSD 3-Clause license.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.

Renumber copyright clause 4

Renumber cluase 4 to 3, per what everybody else did when BSD granted
them permission to remove clause 3. My insistance on keeping the same
numbering for legal reasons is too pedantic, so give up on that point.

Submitted by: Jan Schaumann <jschauma@stevens.edu>
Pull Request: https://github.com/freebsd/freebsd/pull/96

Turns out the emulators still need/want a_magic, so put it back here.

Remove an old hack I noticed years ago, but never committed.

A new jail(8) with a configuration file, to replace the work currently done
by /etc/rc.d/jail.

Merge projects/enhanced_coredumps (r204346) into HEAD:

Enhanced process coredump routines.

This brings in the following features:
1) Limit number of cores per process via the %I coredump formatter.
Example:
if corefilename is set to %N.%I.core AND num_cores = 3, then
if a process "rpd" cores, then the corefile will be named
"rpd.0.core", however if it cores again, then the kernel will
generate "rpd.1.core" until we hit the limit of "num_cores".

this is useful to get several corefiles, but also prevent filling
the machine with corefiles.

2) Encode machine hostname in core dump name via %H.

3) Compress coredumps, useful for embedded platforms with limited space.
A sysctl kern.compress_user_cores is made available if turned on.

To enable compressed coredumps, the following config options need to be set:
options COMPRESS_USER_CORES
device zlib # brings in the zlib requirements.
device gzio # brings in the kernel vnode gzip output module.

4) Eventhandlers are fired to indicate coredumps in progress.

5) The imgact sv_coredump routine has grown a flag to pass in more
state, currently this is used only for passing a flag down to compress
the coredump or not.

Note that the gzio facility can be used for generic output of gzip'd
streams via vnodes.

Obtained from: Juniper Networks
Reviewed by: kan

kern_execve.c hasn't been around in ages, so update the file(s) where
a_magic is used instead of the a_midmag....

# maybe we can retire this hack soon...

- Import the HEAD csup code which is the basis for the cvsmode work.

Capitalize at the start of sentence.

o N_SETMAGIC/N_GET{MAGIC,MID,FLAG} macros live in imgact_aout.h
not in a.out.h. Update the comment accordingly.

PR: kern/80741
Submitted by: Wojciech A. Koszek
MFC after: 3 days

Adjust the system endian and a.out headers to be more MI and cross-building
friendly. Use the systems headers rather than local versions.

Reviewed by: ru

Define MID_ARM6.

Remove advertising clause from University of California Regent's license,
per letter dated July 22, 1999.

Approved by: core

Forward declare struct vnode so that <sys/vnode.h> or some other header
that happens to forward declare struct vnode isn't a prerequisite (most
places get it from <sys/imgact.h>).

Remove __P

Add the following functions/macros to support byte order conversions and
device drivers for bus system with other endinesses than the CPU (using
interfaces compatible to NetBSD):

- bwap16() and bswap32(). These have optimized implementations on some
architectures; for those that don't, there exist generic implementations.
- macros to convert from a certain byte order to host byte order and vice
versa, using a naming scheme like le16toh(), htole16().
These are implemented using the bswap functions.
- stream bus space access functions, which do not perform a byte order
conversion (while the normal access functions would if the bus endianess
differs from the CPU endianess).

htons(), htonl(), ntohs() and ntohl() are implemented using the new
functions above for kernel usage. None of the above interfaces is currently
exported to user land.

Make use of the new functions in a few places where local implementations
of the same functionality existed.

Reviewed by: mike, bde
Tested on alpha by: mike

o Move NTOHL() and associated macros into <sys/param.h>. These are
deprecated in favor of the POSIX-defined lowercase variants.
o Change all occurrences of NTOHL() and associated marcros in the
source tree to use the lowercase function variants.
o Add missing license bits to sparc64's <machine/endian.h>.
Approved by: jake
o Clean up <machine/endian.h> files.
o Remove unused __uint16_swap_uint32() from i386's <machine/endian.h>.
o Remove prototypes for non-existent bswapXX() functions.
o Include <machine/endian.h> in <arpa/inet.h> to define the
POSIX-required ntohl() family of functions.
o Do similar things to expose the ntohl() family in libstand, <netinet/in.h>,
and <sys/param.h>.
o Prepend underscores to the ntohl() family to help deal with
complexities associated with having MD (asm and inline) versions, and
having to prevent exposure of these functions in other headers that
happen to make use of endian-specific defines.
o Create weak aliases to the canonical function name to help deal with
third-party software forgetting to include an appropriate header.
o Remove some now unneeded pollution from <sys/types.h>.
o Add missing <arpa/inet.h> includes in userland.

Tested on: alpha, i386
Reviewed by: bde, jake, tmm

KSE Milestone 2
Note ALL MODULES MUST BE RECOMPILED
make the kernel aware that there are smaller units of scheduling than the
process. (but only allow one thread per process at this time).
This is functionally equivalent to teh previousl -current except
that there is a thread associated with each process.

Sorry john! (your next MFC will be a doosie!)

Reviewed by: peter@freebsd.org, dillon@freebsd.org

X-MFC after: ha ha ha ha

Change #ifdef KERNEL to #ifdef _KERNEL in the public headers. "KERNEL"
is an application space macro and the applications are supposed to be free
to use it as they please (but cannot). This is consistant with the other
BSD's who made this change quite some time ago. More commits to come.

Fixed style bugs in prototype for aout_coredump() (mainly wrapping it with
__BEGIN_DECLS/__END_DECLS to support C++ in 0.001% of the kernel).

General cleanup of core-dumping code.

Submitted by: Sean Fagan,

$Id$ -> $FreeBSD$

Add provisions for variant core dump file formats, depending on the
object format of the executable being dumped. This is the first
step toward producing ELF core dumps in the proper format. I will
commit the code to generate the ELF core dumps Real Soon Now. In
the meantime, ELF executables won't dump core at all. That is
probably no less useful than dumping a.out-style core dumps as they
have done until now.

Submitted by: Alex <garbanzo@hooked.net> (with very minor changes by me)

Made N_TXTADDR() work for kernels (assume that a ZMAGIC file with an
out of bounds a_entry is a kernel and use the usual kludge to find
the text address). If gdb had used this, it would have been able
to find the kernel text address properly. Unfortunately, it uses
its own a.out macros, so this is mainly an example for gdb to copy.

Back out part 1 of the MCFH that changed $Id$ to $FreeBSD$. We are not
ready for it yet.

Make the long-awaited change from $Id$ to $FreeBSD$

This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.

Boy, I'm glad we're not using sup anymore. This update would have been
insane otherwise.

Fix a bunch of spelling errors in the comment fields of
a bunch of system include files.

Corrected a comment.

Submitted by: Sean Eric Fagan

Remove trailing whitespace.

Avoid compiler warnings for overflow in ~(__LDPGSZ - 1).

New file to contain a.out specific macros and definitions.