#!/bin/ksh -p
#
# Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
# Use is subject to license terms.
#
# ident	"%Z%%M%	%I%	%E% SMI"

#
# Find dead functions in a given kernel module.  Requires that system its
# running on matches the source tree
#

GATE=${GATE:-/ws/onnv-gate} export GATE
BUILD_TOOLS=${BUILD_TOOLS:-/ws/onnv-tools} export BUILD_TOOLS
TMPDIR=/tmp/dead-funcs.$$ export TMPDIR
PATH=/usr/bin:/usr/ccs/bin:${BUILD_TOOLS}/onbld/bin/`uname -p`/ export PATH
unset CSCOPEOPTIONS
prog=`basename $0`

trap 'rm -rf $TMPDIR' EXIT

die() {
	print -u2 "$prog: fatal: $*"
	cd /
	exit 1
}

warn() {
	print -u2 "$prog: warning: $*"
}

info() {
	print "$prog: $*"
}

[[ "$#" -lt 1 ]] && die "usage: $prog <kmod> ..."
mkdir $TMPDIR	 || die "cannot create $TMPDIR"

for kmod; do
	if [[ ! -f $kmod ]]; then
		warn "$kmod does not exist"
		continue
	fi

	#
	# Get kernel module symbol list
	#
	nm -P $kmod | grep ' [tT]' | cut -f1 -d' ' > $TMPDIR/kmodsyms

	#
	# Cross-reference symbol list against cscope
	#
	cd $GATE/usr/src/uts || die "cannot access $GATE/usr/src/uts"
	while read sym; do
		def=`cscope-fast -dq -L1${sym}`
		cscope-fast -dq -L0${sym} | awk '
			/extern/ 	{ next }
			/static/	{ next }
			$0 == def	{ next }
					{ ref++; }
			END 		{ if (ref == 0) print kmod": " sym " unused" }'\
		kmod=$kmod sym=$sym def="$def"
	done < $TMPDIR/kmodsyms
done

exit 0