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 r350957:
Increase YPMAXRECORD to 16M to be compatible with Linux.

Sponsored by: Mellanox Technologies

MFC r302535:

Do not allow whitespace in macro names.

MFC r321846:

Log when we have finished pushing users and groups.

Obtained from: OpenBSD (rev 1.4)

MFC r314451,r314452,r314453,r314456,r314457,r314458,r314459,r314460,r314461,r314462,r314464,r314466,r314468,r314470,r314472,r314478:

r314451:

Use SRCTOP-relative paths to other directories instead of .CURDIR-relative ones

The SRCTOP conversion simplifies pathing in make/displayed output.

Also, while here, change a hardcoded path to ar5523.bin.uu in the make target
with ${.ALLSRC} .

r314452:

Use SRCTOP-relative paths to other directories instead of .CURDIR-relative ones

r314453:

Use SRCTOP-relative paths to other directories instead of .CURDIR-relative ones

r314456:

Use SRCTOP-relative paths to other directories instead of .CURDIR-relative ones

This simplifies pathing in make/displayed output.

r314457:

Use SRCTOP-relative paths to other directories instead of .CURDIR-relative ones

The SRCTOP conversion simplifies pathing in make/displayed output.

Also, while here, change a hardcoded path to ${RPCDIR}/ypupdate_prot.x in
the make targets with ${.ALLSRC} .

r314458:

Use SRCTOP-relative paths to other directories instead of .CURDIR-relative ones

This simplifies pathing in make/displayed output.

r314459:

Use SRCTOP-relative paths to other directories instead of .CURDIR-relative ones

This simplifies pathing in make/displayed output.

r314460:

Use SRCTOP-relative paths to other directories instead of .CURDIR-relative ones

This simplifies pathing in make/displayed output.

r314461:

Use SRCTOP-relative paths to other directories instead of .CURDIR-relative ones

This simplifies pathing in make/displayed output.

r314462:

Use SRCTOP-relative paths to other directories instead of .CURDIR-relative ones

The SRCTOP conversion simplifies pathing in make/displayed output.

Also, while here, change a hardcoded path to ${RPCDIR}/ypxfrd.x in
the make targets with ${.ALLSRC} .

r314464:

Use SRCTOP-relative paths to other directories instead of .CURDIR-relative ones

This simplifies pathing in make/displayed output.

r314466:

Use SRCTOP-relative paths to other directories instead of .CURDIR-relative ones

This simplifies pathing in make/displayed output.

r314468:

Use SRCTOP-relative paths to other directories instead of .CURDIR-relative ones

Also, use :H where possible/sensical to manipulate .CURDIR-relative paths

This simplifies pathing in make/displayed output.

r314470:

Use SRCTOP-relative paths to other directories instead of .CURDIR-relative ones

This simplifies pathing in make/displayed output.

r314472:

Simplify/improve idioms in usr.sbin/ntp Makefiles

- Use SRCTOP-relative paths to other directories instead of
.CURDIR-relative ones. This simplifies pathing in make/displayed output.
- Also, use :H where possible/sensical to manipulate .CURDIR-relative
paths
- Remove superfluous bsd.own.mk .includes which are already handled via
src.opts.mk .includes

r314478:

Simplify idioms in Makefiles further

- Use SRCTOP-relative paths instead of .CURDIR-relative ones where possible
- Use :H to manipulate .CURDIR in areas instead of ..-relative paths.

MFC r305303:

DIRDEPS_BUILD: Update dependencies after a 'make bootstrap-tools'.

MFC r305148:

DIRDEPS_BUILD: Add some missing dirctories to the build.

MFC r309392, r309393

r309392:
String terminators are called NUL, not NULL, also the variable
mentioned in the comment is p and not u.

Obtained from: OpenBSD (r1.34)

r309393:
Use memset(3) instead of bzero(3).

Obtained from: OpenBSD (r1.12, r1.20, r1.18 and r1.37)

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

Bump date in both manpages.

Reported by: rodrigc

Add an entry on rc.conf(5) explaining the new options
nis_ypldap_enable and nis_ypldap_flags.

Also add an entry on ypldap(8) that it is a feature ready and
appears on FreeBSD 11.0.

Requested by: rodrigc
Relnotes: Yes

Fix Coverity CIDs 1340544 Resource leak and 1340543 Use after free

At line 479 of ldapclient.c in client_build_req(), the error return
leaks ldap_attrs (CID 1340544). It looks like this can happen if
the first utoa() call in aldap_get_stringset() fails. It looks
like other leaks can happen if other utoa() calls fail since scanning
this array when it is freed stops when the first NULL is encountered.
Fix these problems by not storing NULL in the array when utoa()
fails, and by freeing ret and returning NULL if nothing is stored
in the array. That way the caller will never see the
ldap_attrs[0] == NULL case, so delete that check.

The ber_printf_element() calls ber_free_elements() on its ber
argument and returns NULL on failure. When each of its callers
detects failure, they do a goto fail, which then calls ber_free_elements()
with the same pointer (CID 1340543). Fix is to delete the
ber_free_elements() from ber_printf_element()

Reported by: Coverity
CID: 1340543, 1340544
Reviewed by: araujo
Differential Revision: https://reviews.freebsd.org/D6550

Simplify overengineered and buggy code that looked like as if it did
some kind of UTF-8 validation, but actually didn't, but instead, for
malformed UTF-8 input, caused buffer overruns in some cases and caused
skipping of valid ASCII characters in other cases.

Obtained from: OpenBSD (cvs 1.32)

When a group contains a non-existent user, make the warning
message more helpful by mentioning the group name.

Obtained from: OpenBSD (cvs 1.19)

Avoid indexing an array with a negative value.

Reported by: Coverity
CID: 971121

Use nitems instead of 'sizeof(mapnames) / sizeof(mapnames[0]'.

Convert ypldap_addr list to a tailq(queue(3)).

Obtained from: OpenBSD r1.11, r1.17 and r1.36

Apply revisions 1.4 and 1.5 from ldapd's ber.c to ypldap's copy, so it can
deal with messages that haven't been fully read from the server yet.

Obtained from: OpenBSD r1.11

Set argument encode/result decode call backs for 'maplist' and 'all'.

Note: Listing a map is still not fully implemented.

Obtained from: OpenBSD (r1.16, r1.17)

Implement the 'master' request.

Obtained from: OpenBSD (r1.15)

Switch from FD_SETSIZE to getdtablesize(2) as it can make the FD to be
tunable. Also it gets more close with the original implementation from
OpenBSD.

Requested by: rodrigc
Approved by: rodrigc (mentor)
Differential Revision: https://reviews.freebsd.org/D4970

ypldap(8) is a feature ready to be used to translate nis(8) database to ldap(3).

This commit, fix a core dump on ypldap(8) related with memory allocation.
Also an example of how to set the ypldap.conf(5) properly is added to
examples files.

A new user _ypldap is required to be able to run ypldap(8) as well as
in a chroot mode.

Reviewed by: rodrigc (mentor), bjk
Approved by: bapt (mentor)
Relnotes: Yes
Sponsored by: gandi.net
Differential Revision: https://reviews.freebsd.org/D4744

Remove a garbage printf used for debug.

Approved by: bapt (mentor implicit)

Remove the null checker before free.

Approved by: bapt (mentor)
Obtained from: OpenBSD
Differential Revision: https://reviews.freebsd.org/D4549

Remove wrong header and the NULL check before free().

Approved by: bapt (mentor)
Obtained from: OpenBSD
Differential Revision: https://reviews.freebsd.org/D4548

EAGAIN handling for imsg_read.

Approved by: bapt (mentor)
Obtained from: OpenBSD
Differential Revision: https://reviews.freebsd.org/D4547

Add include of signal.h for signal() prototype.

Replace __svc_fdset with svc_fdset.

FreeBSD lacks __svc_fdset and __svc_fdsetsize.

Do not use SA_LEN() to dereference sa_len.

FreeBSD lacks the SA_LEN() macro.

Add include of time.h for tzset() prototype.

Replace __dead with __dead2.

FreeBSD lacks __dead.

Add include of sys/param.h for MAXHOSTNAMELEN

Replace __dead with __dead2.

FreeBSD lacks __dead.

Replace HOST_NAME_MAX with MAXHOSTNAMELEN.

FreeBSD lacks HOST_NAME_MAX.

Remove reference to EAI_NODATA.

It does not exist on FreeBSD.

Add include of <string.h> for strlen() prototype.

Convert Makefile to FreeBSD style.

Add libopenbsd to link line for imsg.

Import ypldap from OpenBSD.

ypldap -- Intended to be a drop-in replacement for ypserv, gluing in a
LDAP directory and thus providing support for users and groups stored in
LDAP for the get{pw,gr}ent family of functions.