#!/usr/bin/env bash
#
# Test qemu-img convert --salvage
#
# Copyright (C) 2019 Red Hat, Inc.
#
# 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, see <http://www.gnu.org/licenses/>.
#

# creator
owner=mreitz@redhat.com

seq=$(basename $0)
echo "QA output created by $seq"

status=1	# failure is the default!

_cleanup()
{
    _cleanup_test_img
}
trap "_cleanup; exit \$status" 0 1 2 3 15

# get standard environment, filters and checks
. ./common.rc
. ./common.filter
. ./common.qemu

_supported_fmt generic
_supported_proto file
_supported_os Linux
_unsupported_imgopts "subformat=streamOptimized"

if [ "$IMGOPTSSYNTAX" = "true" ]; then
    # We use json:{} filenames here, so we cannot work with additional options.
    _unsupported_fmt $IMGFMT
else
    # With VDI, the output is ordered differently.  Just disable it.
    _unsupported_fmt vdi
fi


TEST_IMG="$TEST_IMG.orig" _make_test_img 64M

$QEMU_IO -c 'write -P 42 0 64M' "$TEST_IMG.orig" | _filter_qemu_io


sector_size=512

# Offsets on which to fail block-status.  Keep in ascending order so
# the indexing done by _filter_offsets will appear in ascending order
# in the output as well.
status_fail_offsets="$((16 * 1024 * 1024 + 8192))
                     $((33 * 1024 * 1024 + 512))"

# Offsets on which to fail reads.  Keep in ascending order for the
# same reason.
# The second element is shared with $status_fail_offsets on purpose.
# Starting with the third element, we test what happens when a
# continuous range of sectors is inaccessible.
read_fail_offsets="$((32 * 1024 * 1024 - 65536))
                   $((33 * 1024 * 1024 + 512))
                   $(seq $((34 * 1024 * 1024)) $sector_size \
                         $((34 * 1024 * 1024 + 4096 - $sector_size)))"


# blkdebug must be above the format layer so it can intercept all
# block-status events
source_img="json:{'driver': 'blkdebug',
                  'image': {
                      'driver': '$IMGFMT',
                      'file': {
                          'driver': 'file',
                          'filename': '$TEST_IMG.orig'
                      }
                  },
                  'inject-error': ["

for ofs in $status_fail_offsets
do
    source_img+="{ 'event': 'none',
                   'iotype': 'block-status',
                   'errno': 5,
                   'sector': $((ofs / sector_size)) },"
done

for ofs in $read_fail_offsets
do
    source_img+="{ 'event': 'none',
                   'iotype': 'read',
                   'errno': 5,
                   'sector': $((ofs / sector_size)) },"
done

# Remove the trailing comma and terminate @inject-error and json:{}
source_img="${source_img%,} ] }"


echo


_filter_offsets() {
    filters=

    index=0
    for ofs in $1
    do
        filters+=" -e s/$ofs/status_fail_offset_$index/"
        index=$((index + 1))
    done

    index=0
    for ofs in $2
    do
        filters+=" -e s/$ofs/read_fail_offset_$index/"
        index=$((index + 1))
    done

    sed $filters
}

# While determining the number of allocated sectors in the input
# image, we should see one block status warning per element of
# $status_fail_offsets.
#
# Then, the image is read.  Since the block status is queried in
# basically the same way, the same warnings as in the previous step
# should reappear.  Interleaved with those we should see a read
# warning per element of $read_fail_offsets.
# Note that $read_fail_offsets and $status_fail_offsets share an
# element (read_fail_offset_1 == status_fail_offset_1), so
# "status_fail_offset_1" in the output is the same as
# "read_fail_offset_1".
$QEMU_IMG convert --salvage "$source_img" "$TEST_IMG" 2>&1 \
    | _filter_offsets "$status_fail_offsets" "$read_fail_offsets"

echo

# The offsets where the block status could not be determined should
# have been treated as containing data and thus should be correct in
# the output image.
# The offsets where reading failed altogether should be 0.  Make them
# 0 in the input image, too, so we can compare both images.
for ofs in $read_fail_offsets
do
    $QEMU_IO -c "write -z $ofs $sector_size" "$TEST_IMG.orig" \
        | _filter_qemu_io \
        | _filter_offsets '' "$read_fail_offsets"
done

echo

# These should be equal now.
$QEMU_IMG compare "$TEST_IMG.orig" "$TEST_IMG"


# success, all done
echo "*** done"
rm -f $seq.full
status=0