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#! /bin/bash

# Copyright (C) 2011 GRNET S.A. 

#

# This program is free software; you can redistribute it and/or modify

# it under the terms of the GNU General Public License as published by

# the Free Software Foundation; either version 2 of the License, or

# (at your option) any later version.

#

# This program is distributed in the hope that it will be useful, but

# WITHOUT ANY WARRANTY; without even the implied warranty of

# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

# General Public License for more details.

#

# You should have received a copy of the GNU General Public License

# along with this program; if not, write to the Free Software

# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA

# 02110-1301, USA.

### BEGIN TASK INFO

# Provides:		FixPartitionTable

# RunBefore:		FilesystemResizeUnmounted

# Short-Description:	Enlarge last partition to use all the available space

### END TASK INFO

set -e

. "@commondir@/common.sh"

# Check if the task should be prevented from running.

check_if_excluded

if [ ! -b "$SNF_IMAGE_DEV" ]; then

    log_error "Device file:\`${SNF_IMAGE_DEV}' is not a block device"

fi

table=$(get_partition_table "$SNF_IMAGE_DEV")

if [ $(get_partition_count "$table") -eq 0 ]; then

    log_error "Device: \`${SNF_IMAGE_DEV}' does not contain any partition"

fi

table_type=$(get_partition_table_type "$table")

if [ "$table_type" == "gpt" ]; then

    "@scriptsdir@/fix_gpt.py" "$SNF_IMAGE_DEV" $($BLOCKDEV --getsz "$SNF_IMAGE_DEV")

elif [ "$table_type" != "msdos" ]; then

    log_error "Device: \'${SNF_IMAGE_DEV}' contains unsupported partition "

    "table type: \`$table_type'. Only msdos & gpt partitions are supported."

fi

last_part=$(get_last_partition "$table")

last_part_id=$(cut -d':' -f1 <<< "$last_part")

# Check if swap is defined...

if [ -n "$SNF_IMAGE_PROPERTY_SWAP" ]; then

    if [[ "$SNF_IMAGE_PROPERTY_SWAP" =~ ^([0-9]+):([0-9]+)$ ]]; then

        swap_num=${BASH_REMATCH[1]}

        swap_size=${BASH_REMATCH[2]}

        swap_unit="MB"

    else

        log_error "SWAP property \`$SNF_IMAGE_PROPERTY_SWAP' is not valid"

    fi

fi

if [ -z "$swap_num" ]; then

    swap_num=0

fi

# Most partition setups leave 2048s in the end. For GPT partitions you need at

# least 34s for the secondary GPT header.

new_end="-2049"

if [ $swap_num -ne 0 ]; then

    free=$(get_last_free_sector "$SNF_IMAGE_DEV" "$swap_unit")

    free_size=$(cut -d: -f4 <<< "$free")

    free_size_val=${free_size/$swap_unit/}

    if [ $free_size_val -le $swap_size ]; then

        log_error "Not enough space for swap partition"

    fi

    swap_end="$new_end"

    swap_start=$((new_end - (swap_size * 2048) + 1)) # in sectors

    new_end=$((swap_start - 1))

fi

extended=""

if [ "$table_type" != "msdos" ]; then

    # Primary, extended and logical partitions is a concept for msdos partition

    # tables. Parted's mkpart will use part-type as partition name if applied

    # on a gpt table and leaving this empty is fragile: For a strange reason

    # for swap partitions the command fails (???)

    last_part_type="primary"

elif [ $last_part_id -gt 4 ]; then

    last_part_type="logical"

    extended=$(get_extended_partition "$table")

    last_primary=$(get_last_primary_partition "$table")

    ext_id=$(cut -d':' -f1 <<< "$extended")

    last_prim_id=$(cut -d':' -f1 <<< "$last_primary")

    if [ "$ext_id" != "$last_prim_id" ]; then

        # Mark last primary as the last partition

        last_part="$extended"

        last_part_id="$ext_id"

        last_part_type="primary"

    else

        # Enlarge the extended partition

        if [ $swap_num -ge 5 ]; then

            # This is needed because logical partitions need to have at least

            # 1 sector gap between them. We make the gap 2048 sectors to

            # properly align them.

            new_end=$((new_end - 2048))

            enlarge_partition "$SNF_IMAGE_DEV" "$extended" "extended" "${swap_end}s"

        else

            enlarge_partition "$SNF_IMAGE_DEV" "$extended" "extended" "${new_end}s"

        fi

    fi

elif [ $(is_extended_partition "$SNF_IMAGE_DEV" "$last_part_id") = "yes" ]; then

    last_part_type="extended"

    extended="$last_part"

    if [ $swap_num -ge 5]; then

        new_end=$swap_end

    fi

else

    last_part_type="primary"

    if [ $swap_num -ge 5 ]; then

        # This is needed because the swap partition should be added inside a

        # new extended partition. In order to align the swap partition, we

        # need to create some extra space between the (aligned) primary and

        # the swap.

        new_end=$((new_end - 2048))

    fi

fi

enlarge_partition "$SNF_IMAGE_DEV" "$last_part" "$last_part_type" "${new_end}s"

if [ $swap_num -gt 0 ]; then

    swap_part="$swap_num:${swap_start}s:${swap_end}s:0:linux-swap(v1)::;"

    if [ "$table_type" != "msdos" ]; then

        swap_ptype="swap" # in gpt this is used as a partition name

    elif [ $swap_num -ge 5 ]; then

        if [ -z "$extended" ]; then

            extended="0:$((swap_start - 2))s:${swap_end}s:0:::;"

            create_partition "$SNF_IMAGE_DEV" "$extended" "extended"

        fi

        swap_ptype="logical"

    else

        swap_ptype="primary"

    fi

    create_partition "$SNF_IMAGE_DEV" "$swap_part" "$swap_ptype"

fi

# Inform the kernel about the changes

partprobe "$SNF_IMAGE_DEV"

exit 0

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