Kernel Configuration script [was Re: "Next Generation" kernel configuration?]

[William Kirkland]

On Tue, Jul 20, 2004 at 07:39:31PM -0500, Conrad J. Sabatier wrote:
> Just musing on an idea here:
> 
> I've been thinking for a while now about trying to write a tool to make
> kernel configuration easier, sort of a "make config" (as in ports) for
> the kernel, similar to what's available on some of the Linux distros.

Ok, I have attached some scripts I wrote, to make my life simpler.
Though I do have some concerns that one should write their own, or use
the existing structure and tools. I am willing to show what I use and
share ideas. 

If you choose to use this, please give credit where it is due. As I
have never previously published this, nor anything else. I find the GNU
GPL (http://www.gnu.org/copyleft/gpl.html) acceptable. Use at your own
risk.

My scripts parces the boot information from /var/log/messages, then
builds a kernel configuration file from that and a configuration file.
I have, just now, written a brief overview of what is done and am
willing to provide more information if you ask. I suppose I could even
clean it up a bit and write proper documentation.

The profile is a bit overly complex, though I use it for a number of
other scripts as well. Sufice it to say, it searches (based upon the
PATH environmental variable, replacing "/bin:" and "/sbin:" with
"/etc:" for an appropriate configuration file (one that has the script
name, minus an optional .sh and appending a .cfg, as a sufix). Once
the file is found, appropriate variables are set.

The performance can be enhanced by setting the "grep" variable, so
that only the relevent boot entries are parced, or copying the message
file somewhere else, then setting the "boot" variable to point to that
file.

Options and and device entries are included if a reference is found
for them in the /var/log/messages file. The exclude and include
configuration variables, modify this behavior, in that the script does
not find references for everything in the boot record, and also finds
references to things I do not use.

You should probably uncomment line 34, and verify the results, prior to
using. For that matter, there are a number of other things you should
understand prior to use (review it before you use it!).


#! /bin/sh
#- -r-xr-xr-x  1 root  wheel  1285 May  9 20:20 /wek/bin/kernel.sh
. /wek/bin/_profile

if [ ! -f "${_kernel_dst}" ]; then
grep -E "${_kernel_grep:-.*}" ${_kernel_boot:-/var/log/messages} >${tmp}
awk -v K=${_kernel} -v B=${tmp} -v P=${_kernel_prefix} \
	-v I="${_kernel_include}" -v X="${_kernel_exclude}" '
BEGIN {	while( getline <B ) {
		if ( $0 ~ P && $5 == "kernel:" && $6 ~ "[0-9]:$" ) {
			sub( "[0-9]:$", "", $6 ); D[$6]++
	}	}
	z=split( I, Z ); for( i=1; i<=z; i++ ) { d=Z[i]; D[d]++ }
	z=split( X, Z ); for( i=1; i<=z; i++ ) { d=Z[i]; D[d]=0 }
}
/^[ #	]*ident[ 	]/ { printf( "ident %s\n", K ); next }
/^[ #	]*device[ 	]/ {
	sub( "^[ #	]*", "" )
	sub( "[ 	]*$", "" )
	if ( D[$2] == 0 ) { printf( "#- %s\n", $0 )
	} else { printf( "%s #=%d\n", $0, D[$2] ) }
	next }
/^[ #	]*(options|cpu)[ 	]/ {
	if ( D[$2] != "" ) {
	sub( "^[ #	]*", "" )
	sub( "[ 	]*$", "" )
	if ( D[$2] == 0 ) { printf( "#- %s\n", $0 )
	} else { printf( "%s #=%d\n", $0, D[$2] ) }
	next }	}
/./ { print }' <${_kernel_src:-/dev/null} >${_kernel_dst}
	if [ -f "${_kernel_add}" ]; then
		cat ${_kernel_add} >>${_kernel_dst}
	fi
rm -f ${tmp} 2>/dev/null
#- exit
fi

( uname -a; date; set -o xtrace
	printenv | grep "^_${P}" | sort
	cd /usr/src && make -i depend \
		&& make buildkernel	KERNCONF=${_kernel}	\
		&& make installkernel	KERNCONF=${_kernel}
) 2>&1 | tee ${_kernel_log}

#- -r--r--r--  1 operator  wheel  126 Apr 23 15:50 /wek/etc/kernel.add
#- options		FAST_IPSEC		# new IPsec
options		IPSEC
options		IPSEC_ESP
options		IPFIREWALL
options		IPDIVERT
options		DUMMYNET


#- -r--r--r--  1 operator  wheel  372 May  9 13:59 /wek/etc/kernel.cfg
wek-*
	boot=/tmp/boot
	boot=/var/log/messages
	src=/usr/src/sys/$( uname -m )/conf/GENERIC
	dst=/usr/src/sys/$( uname -m )/conf/${_kernel}
	include="atadisk atapicd atapifd atapist random loop ether pty md bpf miibus gif sis"
	exclude="INET6 MD_ROOT NFS_ROOT I486_CPU I586_CPU SMP plip"
	add=${home}/etc/${P}.add
	log=${home}/log/${_kernel}


#! /bin/sh
#- -rw-r--r--  1 root  wheel  742 May 11 14:39 /wek/bin/_profile

P=$( basename ${0%.*} )
export home=/wek
export tmp=/tmp/$$
export log=/tmp/${P}-$( date "+%y%m%d" )

for T in $( echo ${PATH}:${home}/etc \
| sed 's|/[s]*bin:|/etc |g' | tr ":" " " ); do
	if [ -z "${cfg}" -a -r ${T}/${P}.cfg ]; then
		cfg=${T}/${P}.cfg
	fi
done
awk -F = -v P=${P} -v M="${1:-$( date '+wek-%y%m%d' )}" '
/^[^ 	]/ { ok=0; if ( M ~ $1 ) { print "export _" P "=" M; ok=1; next } }
/^[ 	]+[A-Z0-9a-z_]*[ 	]*=/ { if ( ok ) {
	gsub( "^[ 	]*", "export _" P "_" ); print
}	}' ${cfg:-/dev/null} >${tmp}
. ${tmp} && rm ${tmp}
export PATH=${home}/bin:${PATH}