MFC r312460:

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

This implifies pathing in make/displayed output

Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

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

General mdoc(7) and typo fixes.

PR: 167734
Submitted by: Nobuyuki Koganemaru (kogane!jp.freebsd.org)
MFC after: 3 days

Remove trailing whitespace per mdoc lint warning

Disussed with: gavin
No objection from: doc
Approved by: joel
MFC after: 3 days

Add the following Linux BlueZ compatibility macros: htobs(), htobl(),
btohs() and btohl()

PR: kern/136386
Submitted by: Monty Hall < kungfu_disciple at sbcglobal dot net >
MFC after: 1 week

Fix typos, spelling, formatting and mdoc mistakes found by Nobuyuki while
translating these manual pages. Minor corrections by me.

Submitted by: Nobuyuki Koganemaru <n-kogane@syd.odn.ne.jp>

Spelling fixes.

Fix typo in bluetooth.3
Do not use reserved C++ keyword "new"

MFC after: 1 month

Bump the version of all non-symbol-versioned shared libraries in
preparation for 8.0-RELEASE. Add the previous version of those
libraries to ObsoleteFiles.inc and bump __FreeBSD_Version.

Reviewed by: kib
Approved by: re (rwatson)

Avoid floating point arithmetic while calculating iquiry length.

Submitted by: Iain Hibbert < plunky -at- rya-online -dot- net >
MFC after: 1 week

Implement low-level Bluetooth HCI API.
This should make it easier to make Linux BlueZ libhci port.

Reviewed by: Iain Hibbert < plunky -at- rya-online -dot- net > of NetBSD
MFC after: 1 week
Inspired by: Linux BlueZ
Inspired by: NetBSD

Add Bluetooth compatibility shims. Inspired by Linux BlueZ and NetBSD.

Discussed with: Iain Hibbert plunky -at- rya-online -dot- net of NetBSD
MFC after: 1 month

Import handy shorthand Bluetooth address (BD_ADDR) utility functions
from NetBSD and document them.

Obtained from: NetBSD
MFC after: 1 week

Bump library versions in preparation for 7.0.

Ok'd by: kan

Bump the shared library version number of all libraries that have not
been bumped since RELENG_5.

Reviewed by: ru
Approved by: re (not needed for commit check but in principle...)

Fix typo in comments (spell Linux correctly)

Submitted by: Markus Brueffer < markus at brueffer dot de >
MFC after: 3 days

Fixed xref.

Sort sections.

Revert last delta. The ASCII code 0 character is "NUL",
not "NULL", see ascii(7).

Fix typo: NUL -> NULL

Submitted by: Markus Brueffer < markus AT brueffer DOT de >
MFC after: 3 days

Unbreak a whatis(1) entry by fixing the NAME section.
Minor markup and grammar nits.

Mechanically kill hard sentence breaks.

Make NULL a (void*)0 whereever possible, and fix the warnings(-Werror)
that this provokes. "Wherever possible" means "In the kernel OR NOT
C++" (implying C).

There are places where (void *) pointers are not valid, such as for
function pointers, but in the special case of (void *)0, agreement
settles on it being OK.

Most of the fixes were NULL where an integer zero was needed; many
of the fixes were NULL where ascii <nul> ('\0') was needed, and a
few were just "other".

Tested on: i386 sparc64

Update Bluetooth code.

Reviewed by: M. Warner Losh <imp@bsdimp.com>; John Hay <jhay@freebsd.org>
Approved by: M. Warner Losh <imp@bsdimp.com> (mentor)