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

Replace index() and rindex() calls with strchr() and strrchr().

The index() and rindex() functions were marked LEGACY in the 2001
revision of POSIX and were subsequently removed from the 2008 revision.
The strchr() and strrchr() functions are part of the C standard.

This makes the source code a lot more consistent, as most of these C
files also call into other str*() routines. In fact, about a dozen
already perform strchr() calls.

Fix minor issues in libstand.

- Don't call tftp_makereq() with too many arguments.
- Don't forget to close one of the comments.

Submitted by: Pawel Worach

put a prefix on dhcp options to avoid clobbering, even by mistake,
existing environment variables.

MFC after: 2 weeks

Some libstand/bootp.c extension (written by Danny Braniss, slightly
revised/modified by me) to store dhcp options into kenv variables,
so the information is available to the boot loader and can be used
to customize the boot process.

The change is totally unintrusive, essentially made of a single
function to be called while parsing a dhcp response, and a couple
of tables to classify options. The values extracted from dhcp
options are stored in the kenv environment in one of these forms:

+ options whose name and type is known are saved as
dhcp.name = value (string, or number/ip addresses lists)

+ unknown options are assumed to be strings and saved as
dhcp.option-NNN = "value"

+ options listed as '__INDIR' and sent on the wire as e.g.
option unknown-252 "some.name=the actual value"
are saved as
some.name = "the actual value"

+ options listed as '__ILIST' and sent on the wire as e.g.
option unknown-249 "a.b=foo bar; c.d= 123; e.f=done"
are saved as multiple values
a.b="foo bar"
c.d="123"
e.f="done"

As you can see there is quite a bit of flexibility on what can
be passed to the loader or the kernel.

For the time being the vendor-specific table is mostly disabled,
because there is no standard set of options for FreeBSD, and I don't
know all the pxe-specific vendor options.

Also, applications using libstand may live in memory-constrained
environments, so it makes sense to keep these tables as small as
possible, especially considering that one can generate arbitrary
name=value pairs using site-specific options of type __INDIR or
__ILIST (there are 4 __ILIST and 5 __INDIR in the table, numbered
246..249 and 250..254).

Actually, considering that probably 75% of the standard dhcp options
are totally useless, it might make sense to remove them as well.

Submitted by: Danny Braniss
MFC after: 4 weeks

Remove California Regent's clause 3, per letter

Remove 'register' keyword.

Add __FBSDID()s to libstand

IN_CLASS*() macros assume host order and s_addr is network byte
order, so we must convert them to host order.

Add support to send the string 'PXEClient' as the Vendor class
identifier to the DHCP server. Now you can check for this string
in your dhcp configuration to decide whether you will hand out a
lease to the client or not.

This commit was generated by cvs2svn to compensate for changes in r38451,
which included commits to RCS files with non-trunk default branches.

This is libstand; a support library for standalone executables (eg. bootstrap
modules).
Obtained from: NetBSD, with some architectural changes and many additions.