image-mount

#!/bin/bash

errexit()
{
  echo ""
  echo "$1"
  echo ""
  exit 1
}

usage()
{
  errexit "Usage: $0 imagefile mountpoint [W95|Linux]"
}

if [ $(id -u) -ne 0 ]; then
  errexit "$0 must be run as root user"
fi

IMG="$1"
MNT="$2"
PART="$3"

if [[ "${IMG}" = "" || "${MNT}" = "" ]]; then
  usage
fi

if [ ! -f "${IMG}" ]; then
  errexit "${IMG} not found"
fi

if [ ! -d "${MNT}" ]; then
  errexit "${MNT} is not a directory"
fi

if [ "${PART}" = "" ]; then
  PART="type=83"
else
  PART="$(tr [A-Z] [a-z] <<< "${PART}")"
  if [ "${PART}" = "w95" ];then
    PART="type=c"
  elif [ "${PART}" = "linux" ];then
    PART="type=83"
  else
    usage
  fi
fi

echo ""
echo -n "Mount ${IMG} on ${MNT} (y/n)? "
while read -r -n 1 -s answer; do
  if [[ "${answer}" = [yYnN] ]]; then
    echo "${answer}"
    if [[ "${answer}" = [yY] ]]; then
      break
    else
      errexit "Aborted"
    fi
  fi
done
echo ""

INFO="$(sfdisk -d "${IMG}")"
START=$(grep "${PART}" <<< "${INFO}" | sed -n 's|^.*start=\s\+\([0-9]\+\).*$|\1|p')
SIZE=$(grep "${PART}" <<< "${INFO}" | sed -n 's|^.*size=\s\+\([0-9]\+\).*$|\1|p')
LOOP="$(losetup -f --show -o $((${START} * 512)) --sizelimit $((${SIZE} * 512)) "${IMG}")"
if [ $? -ne 0 ]; then
  errexit "Unable to create loop device"
fi
if [ "${PART}" = "type=c" ]; then
  dosfsck "${LOOP}"
else
  FS_TYPE=$(blkid "${LOOP}" | sed -n 's|^.*TYPE="\(\S\+\)".*|\1|p')
  if [ "${FS_TYPE}" = "f2fs" ]; then
    fsck.f2fs "${LOOP}"
  else
    fsck.ext4 -f "${LOOP}"
  fi
fi
if [ $? -ne 0 ]; then
  losetup -d "${LOOP}"
  errexit "Filesystem appears corrupted"
fi
mount "${LOOP}" ${MNT}
echo ""
echo "${IMG} mounted on ${MNT}"
echo ""
echo "When done, run:"
echo "umount ${MNT}"
echo "losetup -d ${LOOP}"
echo ""