Copy stable/10@r272459 to releng/10.1 as part of
the 10.1-RELEASE process.

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

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

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

Convert IIJ copyrights to BSD copyrights.

Approved by: Toshiharu OHNO <tohno@sirius.ocn.ne.jp>

$Id$ -> $FreeBSD$

Rather than interrupting 10 times per second then checking
to see if there's anything to do, schedule the next alarm
based on the next required timeout.
This decreases the load when there are lots of relatively
idle ppp processes.

While I'm in there, handle the possibility that a timeout
makes the timer element go out of scope by grabbing the
enext pointer before executing the timer function.

Re-initialise our timer service after fork()ing
to lose our terminal session. Is this a bug in
setitimer() ? - it must be called again in the
child !

MFMP: Make ppp multilink capable.
See the file README.changes, and re-read the man page.

Remove unused #includes.
Make various bits static.
Remove unused variables.
Submitted by: eivind

Don't expect select() to adjust the passed time when it's
interrupted with a SIGALRM. In fact, select() sets the
passed time to zero, making the previous implementation
terminate always after 1/10th of a second !

Also, deal with someone changing the clock while we're
sleeping (and restart the whole sleep).

Dangers pointed out by: Theo de Raadt <deraadt@cvs.openbsd.org>

Fix prototypes.
Remove extraneous decls.
Add ``const'' to several places.
Allow ``make NOALIAS=1'' to remove IP aliasing.
Merge with OpenBSD - only the Makefiles vary.

We can now survive a compile with
-Wall -Wbad-function-cast -Wcast-align -Wcast-qual
-Winline -Wmissing-declarations -Wmissing-prototypes
-Wnested-externs -Wpointer-arith -Wredundant-decls
-Wshadow -Wstrict-prototypes -Wwrite-strings -Wchar-subscripts
(although the Makefile just contains -Wall).

Cosmetic:
Move prototypes into the correct headers.

Cosmetic (no functional changes):
o Add missing $Id$s
o Move extern decls from .c -> .h files
o Staticize
o Remove #includes from .h files
o style(9)ify includes
o bcopy -> memcpy
bzero -> memset
bcmp -> memcmp
index -> strchr
rindex -> strrchr
o Move timeout.h -> timer.h (making it consistent w/ timer.c)
o Add -Wmissing-prototypes