new_install_root

#!/bin/sh
# Licensed to the Apache Software Foundation (ASF) under one or more
# contributor license agreements.  See the NOTICE file distributed with
# this work for additional information regarding copyright ownership.
# The ASF licenses this file to You under the Apache License, Version 2.0
# (the "License"); you may not use this file except in compliance with
# the License.  You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

SCRIPT="new_install_root"

## This script should be called when the read-only ihs install has changed.
DIFF=/bin/diff
SED=/bin/sed

usage() {
    printf "Usage: $0 [-h] [-f] -s INSTALL_TO_MOVE -t NEW_READONLY_ROOT\n"
    printf "\t-h\t Display this help\n"
    printf "\t-f\t Force moving to the new readonly root even if it doesn't exist\n"
    printf "\t-s\t The source symlink install root to change\n"
    printf "\t-t\t The target readonly root to change the source to\n"
}

while getopts "h?fs:t:" opt; do
    case "$opt" in
        h|\?)
            usage
            exit 0
            ;;
        f)
            FORCE_SWITCH=1
            ;;
        s)
            RW_ROOT=$OPTARG
            ;;
        t)
            NEW_RO_ROOT=$OPTARG
            ;;
    esac
done

echo $RW_ROOT|grep "^/" > /dev/null
if [ $? != 0 ]; then
  echo Symlink install directory \"$RW_ROOT\" must be an absolute path
  usage
  exit 1
fi

echo $NEW_RO_ROOT|grep "^/" > /dev/null
if [ $? != 0 ]; then
  echo New read-only directory \"$NEW_RO_ROOT\" should be an absolute path
  usage
  exit 1
fi

if [ ! -L $RW_ROOT/bin/httpd ] ; then
  echo "Install directory \"$RW_ROOT\" doesn't look like a symlinked install (bin/httpd is not a symbolic link)"
  usage
  exit 1
fi

# Make sure the new read-only root looks like an install unless the user knows better
if [ "x$FORCE_SWITCH" = "x" ]; then
    if [ ! -f $NEW_RO_ROOT/bin/httpd ]; then
      echo "$NEW_RO_ROOT doesn't look like a read-only install root ($NEW_RO_ROOT/bin/httpd doesn't exist)"
      usage
      exit 1
    elif [ -L $NEW_RO_ROOT/bin/httpd ]; then
      echo "$NEW_RO_ROOT doesn't look like a read-only install root - ($NEW_RO_ROOT/bin/httpd is a symlink)"
      usage
      exit 1
    fi
fi

# derive root of the current read only tree from bin/httpd symlink target
CURRENT_RO_ROOT=`ls -l $RW_ROOT/bin/httpd | $SED -e 's#.*-> \(.*\)/bin/httpd#\1#'`
  
for F in `find $RW_ROOT`; do
  # Create new symlinks to the files in the NEW_RO_ROOT
  if [ -L $F ] && ls -ld $F | grep "\-> $CURRENT_RO_ROOT" > /dev/null ; then
    # Parsing the output of ls is generally a bad idea, but readlink doesn't exist on z/OS
    NEW_PATH=`ls -l $F | $SED -e "s#.*-> ##" | $SED -e "s#$CURRENT_RO_ROOT#$NEW_RO_ROOT#"`
    echo "'$F' -> '$NEW_PATH'"
    rm $F
    ln -sf $NEW_PATH $F
  fi
done

OLD_LEVEL=`grep 'IBM HTTP Server ' $RW_ROOT/version.signature`
OLD_LEVEL=`echo $OLD_LEVEL | sed -e "s;IBM HTTP Server ;;"`		 
cp $NEW_RO_ROOT/version.signature $RW_ROOT/.
NEW_LEVEL=`grep 'IBM HTTP Server ' $NEW_RO_ROOT/version.signature`
NEW_LEVEL=`echo $NEW_LEVEL | sed -e "s;IBM HTTP Server ;;"`		 

if [ -f $NEW_RO_ROOT/bin/postinst ]; then
    "$NEW_RO_ROOT/bin/postinst" -t update -i "$RW_ROOT"
else
    "$CURRENT_RO_ROOT/bin/postinst" -t update -i "$RW_ROOT"
fi

if [ $? != 0 ]; then
    echo "postinst failed; newly moved root may be unusable"
    exit 1
else
    echo "Moving from $OLD_LEVEL at $CURRENT_RO_ROOT to $NEW_LEVEL at $NEW_RO_ROOT complete"
    exit 0
fi