#!/bin/sh
#
# Update the 2.6 ism workarea with a 2.6 kernel src tree
#
# NEED to update:
# - kernel_version
# - kdb_prefix
# - kdb_suffix
#
#
# Useful commands for the exercise:
# ftp://ftp.kernel.org/pub/linux/kernel/v2.6/linux-2.6.18.tar.gz 50Mb
# cd isms
# bzcat /build/kaos/kernel.org-sgidev/linux-2.6.18.tar.bz2 | tar xvf -
# cd linux-2.6.18
# mkdir patches
# quilt import ~/patches/patch-2.6.19-rc3
# quilt push
#

tmp=/tmp/$$
here=`pwd`
prog=`basename $0`
status=1
debug=false
trap "rm -f $tmp.*; exit \$status" 0 1 2 3 15

patches="split-patches"
tmp_linux_dir=/tmp/$USER.linux_src.$$

cat <<EOF >$tmp.skip
xfs
dmapi
patches
split-patches
*.out.$USER
\.pc
final.*
\.modheader
\.workarea
\.census
census
census,v
*\.prj
*\.prcs_aux
EOF

_usage()
{
    cat << EOF
Usage: $prog version workarea mainline-2.6

version       kernel version like 2.6.19 or 2.6.19-rc3
workarea      ptools 2.6.x-xfs workarea
mainline-2.6  fresh 2.6 mainline src tree or 
              .tar or .tar.gz or .tar.bz2 file
	      (won't delete this tree on exit)
EOF
    exit 1
}

_kdb_all_there()
{
    for file in ${kdb_prefix}{i386,ia64,common,x86_64}${kdb_suffix}
    do
	[ ! -e $file ] && return 1
    done
    return 0
}

_fixup_new_kdb_patches()
{
    cd $ism/$patches
    if _kdb_all_there 
    then
	echo "All kdb patches already present in 2.6 workarea"
	p_state `p_list -c`
	return
    fi

    # fix up kdb patches
    if ls kdb* >/dev/null 2>&1
    then
	p_delete kdb*
    fi

    ftp -aiv "$kdb_ftp_host:$kdb_ftp_dir/$kdb_glob"

    if ! ls kdb* >/dev/null 2>&1
    then
	echo "Failed to download kdb patches: $kdb_ftp_host:$kdb_ftp_dir/$kdb_glob"
	exit
    fi

    p_fetal -kb kdb*

    # fix up series file
    p_modify series
    >series # truncate it
    for f in kdb*
    do
	echo $f | sed 's/\.bz2//' >>series
    done
    echo dmapi-enable >>series

    p_state `p_list -c`
}

# apply to current 2.6 mainline tree
_apply_custom_patches()
{
    cd $kernel_src

    if [ -d kdb ]
    then
	echo "kdb subdir exists assuming kernel already patched"
    else
	echo "apply kdb patches using quilt..."
	[ -d patches ] || mkdir patches
	for p in $ism/$patches/${kdb_prefix}{i386,ia64,common,x86_64}${kdb_suffix}
	do
	    quilt import $p
	    quilt push
	done
    fi	

    if grep -iq dmapi MAINTAINERS
    then 
	echo "DMAPI in MAINTAINERS assuming dmapi patch already applied"
    else
	echo "apply dmapi patches using quilt (in case of failure)..."
	[ -d patches ] || mkdir patches
        quilt import $ism/$patches/dmapi-enable
	quilt push
    fi
}


_new_files()
{
   lsdiff -s $1 | grep '^+' | cut -c3-
}

_deleted_files()
{
   lsdiff -s $1 | grep '^-' | cut -c3-
}

_modified_files()
{
   lsdiff -s $1 | grep '^!' | cut -c3-
}

_process_args()
{
    [ $# -ne 3 ] && _usage

    # kernel version needed for kdb
    kernel_version=$1

    # process ism/workarea argument
    ism=$2
    if [ ! -d $ism ] 
    then
	echo "$prog: $ism is not a directory"
	_usage
    fi
    if [ ! -s $ism/.workarea ]
    then
	echo "$prog: can't find $ism/.workarea"
	_usage
    fi

    # process linux kernel source argument
    kernel_src=$3
    if [ ! -e $kernel_src ]
    then
	echo "$prog: $kerenel_src does not exist"
	_usage
    fi

    # extra handling for kernel src archives
    if [ ! -d $kernel_src ] 
    then
	echo "Making $tmp_linux_dir (will leave behind)"
	mkdir $tmp_linux_dir
	cd $tmp_linux_dir

	echo "$prog: $kerenel_src is not a directory"
	if echo $kernel_src | egrep -q 'tar.bz2$'
	then
	    echo "Uncompressing and untarring src..."
	    bzcat $kernel_src | tar xvf -
	elif echo $kernel_src | egrep -q 'tar.gz2$'
	then
	    echo "Uncompressing and untarring src..."
	    tar -zxvf $kernel_src
	elif echo $kernel_src | egrep -q 'tar$'
	then
	    echo "Untaring src..."
	    tar -xvf $kernel_src
	else
	    echo "$prog: $kerenel_src is not a directory or known extension"
	    _usage
	fi 
	# need to go down 1 level
	kernel_src=$tmp_linux_dir/`ls $tmp_linux_dir`
	echo "using kernel source from $kernel_src" 
    elif [ ! -e $kernel_src/MAINTAINERS ]
    then
	echo "Are you sure the kernel src argument is correct: $kernel_src"
	echo "$kernel_src/MAINTAINERS not found"
	_usage
    fi
    echo "Using mainline source tree of $kernel_src"
}

# --------- main ------------

_process_args $*

kdb_prefix="kdb-v4.4-${kernel_version}-"
kdb_suffix="-1.bz2"
kdb_glob="${kdb_prefix}{i386,ia64,common,x86_64}${kdb_suffix}"
kdb_ftp_host=oss.sgi.com
kdb_ftp_dir=/projects/kdb/download/latest

echo "Update workarea..."
export WORKAREA=$ism
cd $ism
p_tupdate

echo "Files which are not in the census for workarea:"
p_list -W

echo "Update new kdb..."
_fixup_new_kdb_patches

echo "Apply patches to mainline src..."
_apply_custom_patches

echo "Diff 2.6.x-xfs with patched mainline src..."
diff -Naur -X $tmp.skip $ism $kernel_src |\
sed \
-e "s#^--- ${ism}#--- #" \
-e "s#^--- /#--- #" \
-e "s#^+++ ${kernel_src}#+++ #" \
-e "s#^+++ /#+++ #" \
>$tmp.patch

if $debug
then
    cp $tmp.patch $here/THE_PATCH
fi

_new_files $tmp.patch >$tmp.new
_deleted_files $tmp.patch >$tmp.deleted
_modified_files $tmp.patch >$tmp.modified


if $debug
then
    cp $tmp.modified $here/THE_MODIFIED
    cp $tmp.new $here/THE_NEW
    cp $tmp.deleted $here/THE_DELETED
fi

echo "Fix up modified/deleted state for patched files..."
cd $ism
[ -s $tmp.deleted ]  && p_delete -I $tmp.deleted
[ -s $tmp.modified ] && p_modify -I $tmp.modified

echo "Copy over the new and modified files..."
cat $tmp.new $tmp.modified | \
while read file
do
    src_file=$kernel_src/$file
    dst_file=$ism/$file
    dst_dir=`dirname $dst_file`
    [ -d $dst_dir ] || mkdir -p $dst_dir
    echo "cp $src_file $dst_file"
    if ! cp $src_file $dst_file
    then
	echo "Failed to copy from $src_file to $dst_file"
	exit
    fi
done

echo "Fix up fetal state for patched files..."
[ -s $tmp.new ] && p_fetal  -I $tmp.new

status=0