MFC -fno-common fixes: r359389, r359394, r359397-r359399, r359403-r359404,
r359406, r359413-r359416, r359425, r359427, r359432-r359433, r359443,
r359675-r359677

Note: this is not necessarily a complete fix to get these programs to build
with -fno-common applied.

r359389:
config(8): fixes for -fno-common

Move this handful of definitions into main.c, properly declare these as
extern in config.h. This fixes the config(8) build with -fno-common.

Unexplained in my previous commit to gas, -fno-common will become the
default in GCC10 and LLVM11, so it's worth addressing these in advance.

r359394:
MFV r359393: tcsh: import 6974bc35a5cd

This removes an extra variable definition that causes the -fno-common build
to fail, which will be a new default in GCC10/LLVM11.

r359397:
zfs: fix -fno-common issues

A similar (or identical?) fix has already landed in OpenZFS.

-fno-common will become the default in GCC10/LLVM11.

r359398:
sh: remove duplicate el definition

el is declared extern in myhistedit.h and defined in histedit.c. Remove the
duplicate definition in input.c to appease the -fno-common build.

-fno-common will become the default in GCC10/LLVM11.

r359399:
telnet: remove some duplicate definitions, mark terminaltype extern

Most of these were already properly declared and defined elsewhere, this is
effectively just a minor cleanup that fixes the -fno-common build.

-fno-common will become the default in GCC10/LLVM11.

r359403:
Revert 359399: telnet -fno-common bits

There was a large misfire from my local diff that I need to investigate, and
this version committed did not build.

r359404:
Re-apply r359399: telnet -fno-common fix

line and auth_level's redefinitions are just extraneous

telnetd will #define extern and then include ext.h to allocate storage for
all of these extern'd vars; however, two of them are actually defined in
libtelnet instead. Instead of doing an #ifdef extern dance around those
function pointers, just add an EXTERN macro to make it easier to
differentiate by sight which ones will get allocated in globals.c and which
ones are defined elsewhere.

r359406:
telnet: kill off remaining duplicate definition

r359413:
ipfilter: remove duplicate definition of 'thishost'

thishost is already defined in lib/initparse.c; no need for this one. This
fixes the ipfilter build with -fno-common.

-fno-common will become the default in GCC10/LLVM11.

r359414:
iscontrol: move definition of vflag/iscsidev to iscontrol.c

Mark the declaration extern as these are used elsewhere; this fixes the
build with -fno-common.

r359415:
userboot: mark host_fsops as extern

This is already defined elsewhere; mark this declaration extern to the fix
the -fno-common build.

r359416:
systat: remove redundant definition of kd

kd is already properly declared in extern.h and defined in main.c, rendering
this definition useless. This fixes the -fno-common build.

r359425:
locate: fix -fno-common build

Just a single variable declaration to extern and define elsewhere here,
myctype.

-fno-common will become a default in GCC10/LLVM11.

r359427:
fsck_ffs/fsdb: fix -fno-common build

This one is also a small list:

- 3x duplicate definition (ufs2_zino, returntosingle, nflag)
- 5x 'needs extern', 3/5 of which are referenced in fsdb

-fno-common will become the default in GCC10/LLVM11.

r359432:
gdb: compile with -fcommon explicitly

As described in the comment, gdb relies on some of the linker magic that
happens with -fcommon. I suspect the life expectancy of gdb-in-base is low
enough that this isn't worth spending much time addressing, especially given
the vintage. Hit it with the -fcommon hammer so that it continues to just
work.

r359433:
bmake: fix -fno-common build

debug was declared extern, but debug_file was not; correct this and define
debug_file in main.c (as debug is) to fix the -fno-common build.

-fno-common will become the default with GCC10/LLVM11.

r359443:
MFV r359442: bmake: import -fno-common fix build back from upstream

sjg@ committed the local patch previously committed upstream; pull it in to
vendor/ to ease any potential stress of future imports.

r359675:
kqueue tests: fix -fno-common build

vnode_fd and kqfd are both shared among multiple CU; define them exactly
once.

In the case of vnode_fd, it was simply the declaration that needed
correction.

-fno-common will become the default in GCC10/LLVM11.

r359676:
ntpd: fix build with -fno-common

Only a small nit here: psl should be declared extern and defined exactly
once.

-fno-common will become the default in GCC10/LLVM11.

r359677:
yp*: fix -fno-common build

This is mostly two problems spread out far and wide:
- ypldap_process should be declared properly
- debug is defined differently in many programs

For the latter, just extern it and define it everywhere that actually needs
it. This mostly works out nicely for ^/libexec/ypxfr, which can remove the
assignment at the beginning of main in favor of defining it properly.

-fno-common will become the default in GCC10/LLVM11.

MFC r353325, r353875

r353325:
Update tcsh to 6.21.00.

This is a bugfix release with no new features. A number of these fixes
were previously merged into our tree.

Sponsored by: DARPA, AFRL

r353875:
Update tcsh to git revision 83c5be0 bringing in a number of bug fixes.

Reported by: sobomax
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D22099

Record prior MFC of r315948, r315952

MFC r315948:

Update tcsh to 6.20.00

MFC r315952:

Update tcsh to vendor git b605cb561d

Vendor changes:

1. PR/471: Daiki Ueno: Delay interpreting arginp until we've processed
our startup files (which can change the NLS environment).

2. Fix type of read in prompt confirmation (eg. rmstar) (David Kaspar).

3. Fix out of bounds read (Brooks Davis)
(reproduce by starting tcsh and hitting tab at the prompt).

4. Don't play pointer tricks that are undefined in modern c
(Brooks Davis).

MFC r302831

To mimic system glob, we definitely don't need manual upper/lower hack.
The author clearly disagree in the comment, so this patch will be not
submitted upstream.

Copy head@r302406 to stable/11 as part of the 11.0-RELEASE cycle.
Prune svn:mergeinfo from the new branch, as nothing has been merged
here.

Additional commits post-branch will follow.

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

Upgrade our copy of clang, llvm and lldb to 3.5.0 release.

Please note that this version now requires C++11 support to build; see
UPDATING for more information.

Release notes for llvm and clang can be found here:
<http://llvm.org/releases/3.5.0/docs/ReleaseNotes.html>
<http://llvm.org/releases/3.5.0/tools/clang/docs/ReleaseNotes.html>

Thanks to Ed Maste, Roman Divacky, Andrew Turner, Justin Hibbits and
Antoine Brodin for their invaluable help with this import.

Approved by: portmgr (antoine)
MFC after: 1 month

Update to tcsh 6.18.01.

With retirement of cpumask_t and usage of cpuset_t for representing a
mask of CPUs, pc_other_cpus and pc_cpumask become highly inefficient.

Remove them and replace their usage with custom pc_cpuid magic (as,
atm, pc_cpumask can be easilly represented by (1 << pc_cpuid) and
pc_other_cpus by (all_cpus & ~(1 << pc_cpuid))).

This change is not targeted for MFC because of struct pcpu members
removal and dependency by cpumask_t retirement.

MD review by: marcel, marius, alc
Tested by: pluknet
MD testing by: marcel, marius, gonzo, andreast

etire the cpumask_t type and replace it with cpuset_t usage.

This is intended to fix the bug where cpu mask objects are
capped to 32. MAXCPU, then, can now arbitrarely bumped to whatever
value. Anyway, as long as several structures in the kernel are
statically allocated and sized as MAXCPU, it is suggested to keep it
as low as possible for the time being.

Technical notes on this commit itself:
- More functions to handle with cpuset_t objects are introduced.
The most notable are cpusetobj_ffs() (which calculates a ffs(3)
for a cpuset_t object), cpusetobj_strprint() (which prepares a string
representing a cpuset_t object) and cpusetobj_strscan() (which
creates a valid cpuset_t starting from a string representation).
- pc_cpumask and pc_other_cpus are target to be removed soon.
With the moving from cpumask_t to cpuset_t they are now inefficient
and not really useful. Anyway, for the time being, please note that
access to pcpu datas is protected by sched_pin() in order to avoid
migrating the CPU while reading more than one (possible) word
- Please note that size of cpuset_t objects may differ between kernel
and userland. While this is not directly related to the patch itself,
it is good to understand that concept and possibly use the patch
as a reference on how to deal with cpuset_t objects in userland, when
accessing kernland members.
- KTR_CPUMASK is changed and now is represented through a string, to be
set as the example reported in NOTES.

Please additively note that no MAXCPU is bumped in this patch, but
private testing has been done until to MAXCPU=128 on a real 8x8x2(htt)
machine (amd64).

Please note that the FreeBSD version is not yet bumped because of
the upcoming pcpu changes. However, note that this patch is not
targeted for MFC.

People to thank for the time spent on this patch:
- sbruno, pluknet and Nicholas Esborn (nick AT desert DOT net) tested
several revision of the patches and really helped in improving
stability of this work.
- marius fixed several bugs in the sparc64 implementation and reviewed
patches related to ktr.
- jeff and jhb discussed the basic approach followed.
- kib and marcel made targeted review on some specific part of the
patch.
- marius, art, nwhitehorn and andreast reviewed MD specific part of
the patch.
- marius, andreast, gonzo, nwhitehorn and jceel tested MD specific
implementations of the patch.
- Other people have made contributions on other patches that have been
already committed and have been listed separately.

Companies that should be mentioned for having participated at several
degrees:
- Yahoo! for having offered the machines used for testing on big
count of CPUs.
- The FreeBSD Foundation for having sponsored my devsummit attendance,
which has been instrumental.
- Sandvine for having offered offices and infrastructure during
development.

(I really hope I didn't forget anyone, if it happened I apologize in
advance).

Remove unused GPL files from tcsh.

Merger of the quota64 project into head.

This joint work of Dag-Erling Smørgrav and myself updates the
FFS quota system to support both traditional 32-bit and new 64-bit
quotas (for those of you who want to put 2+Tb quotas on your users).

By default quotas are not compiled into the kernel. To include them
in your kernel configuration you need to specify:

options QUOTA # Enable FFS quotas

If you are already running with the current 32-bit quotas, they
should continue to work just as they have in the past. If you
wish to convert to using 64-bit quotas, use `quotacheck -c 64';
if you wish to revert from 64-bit quotas back to 32-bit quotas,
use `quotacheck -c 32'.

There is a new library of functions to simplify the use of the
quota system, do `man quotafile' for details. If your application
is currently using the quotactl(2), it is highly recommended that
you convert your application to use the quotafile interface.
Note that existing binaries will continue to work.

Special thanks to John Kozubik of rsync.net for getting me
interested in pursuing 64-bit quota support and for funding
part of my development time on this project.

Fix tcsh losing history when tcsh terminates because the pty beneath it
is closed.

Diagnosed by Ted Anderson:

New signal queuing logic was introduced in 6.15 and allows the signal handlers
to be run explicitly by calling handle_pending_signals, instead of
immediately when the signal is delivered. This function is called at
various places, typically when receiving a EINTR from a slow system call
such as read or write. In the pty exit case, it was called from xwrite,
called from flush, while printing the "exit" message after receiving EOF
when reading from the pty (note that the read did not return EINTR but
zero bytes, indicating EOF). The SIGHUP handler, phup(), called
rechist, which opened the history file and began writing the merged
history to it. This process invoked flush recursively to actually write
the data. In this case, however, the flush noticed it was being called
recursively and decided fail by calling stderror.

My conclusion was that the signal was being handled at a bad time. But
whether to fix flush not to care about the recursive call, or to handle
the signal some other time and when to handle it, was unclear to me.
However, by adding an extra call to handle_pending_signals, just after
process() returns to main(), I was able to avoid the truncated history
after network outages and similar failures. I verified this fix in
version 6.17.

Approved by: ed (mentor)
MFC after: 1 week

Update to tcsh 6.17.00.

Approved by: re (kensmith)

Bootstrap merge history.

Approved by: re

Usermode portion of the support for swap allocation accounting:
- update for getrlimit(2) manpage;
- support for setting RLIMIT_SWAP in login class;
- addition to the limits(1) and sh and csh limit-setting builtins;
- tuning(7) documentation on the sysctls controlling overcommit.

In collaboration with: pho
Reviewed by: alc
Approved by: re (kensmith)

Actually fix pty detection for autologout setting.
(The fix has been submitted upstream.)

tcsh: fix abort in cleanup_until(), caused by internal xgetpass()

The xgetpass() function pushes a cleanup entry for &osa, but then
attempts to flush the stack until an entry matching &sa. The two
object pointers do not match, so the stack is popped too much,
and then cleanup_until calls abort() when it unexpectedly hits
the bottom of the cleanup stack.

Reported by: Paul B. Mahol, onemda at gmail.com,
Pietro Cerutti, gahr at gahr.ch
PR: bin/124191
Reviewed by: mp, kris
MFC after: 2 days

This commit was generated by cvs2svn to compensate for changes in r177128,
which included commits to RCS files with non-trunk default branches.

This commit was generated by cvs2svn to compensate for changes in r172668,
which included commits to RCS files with non-trunk default branches.

This commit was generated by cvs2svn to compensate for changes in r172665,
which included commits to RCS files with non-trunk default branches.

This commit was generated by cvs2svn to compensate for changes in r168305,
which included commits to RCS files with non-trunk default branches.

Build updates for tcsh-6.15.00 import.

Reviewed by: ume
Reminded by: Divacky Roman
MFC after: 1 week

This commit was generated by cvs2svn to compensate for changes in r167465,
which included commits to RCS files with non-trunk default branches.

Remove the nls/*/charset files to the exclude list. These files
are required for NLS catalog support.

This commit was generated by cvs2svn to compensate for changes in r155832,
which included commits to RCS files with non-trunk default branches.

This commit was generated by cvs2svn to compensate for changes in r145479,
which included commits to RCS files with non-trunk default branches.

Add the nls/*/charset files to the exclude list. These files are not needed
and only provide comments in the text NLS files.

This commit was generated by cvs2svn to compensate for changes in r131962,
which included commits to RCS files with non-trunk default branches.

Document upgrade procedure.

This commit was generated by cvs2svn to compensate for changes in r100616,
which included commits to RCS files with non-trunk default branches.

This commit was generated by cvs2svn to compensate for changes in r90446,
which included commits to RCS files with non-trunk default branches.

This commit was generated by cvs2svn to compensate for changes in r83098,
which included commits to RCS files with non-trunk default branches.

This commit was generated by cvs2svn to compensate for changes in r73393,
which included commits to RCS files with non-trunk default branches.

This file not present in 6.10

This commit was generated by cvs2svn to compensate for changes in r69408,
which included commits to RCS files with non-trunk default branches.

This commit was generated by cvs2svn to compensate for changes in r68332,
which included commits to RCS files with non-trunk default branches.

This commit was generated by cvs2svn to compensate for changes in r61524,
which included commits to RCS files with non-trunk default branches.

This commit was generated by cvs2svn to compensate for changes in r61521,
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This commit was generated by cvs2svn to compensate for changes in r61519,
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This commit was generated by cvs2svn to compensate for changes in r61515,
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This commit was generated by cvs2svn to compensate for changes in r59901,
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This commit was generated by cvs2svn to compensate for changes in r59419,
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This commit was generated by cvs2svn to compensate for changes in r59415,
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This commit was generated by cvs2svn to compensate for changes in r59243,
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