Remove sheet protections in Excel workbooks

unprotect-excel.sh

#!/usr/bin/env bash

# Evan Rees
# err87@cornell.edu
# August 2021

# Remove sheet protections from .xlsx or .xls files

usage() {
  cat <<EOF
Remove sheet protections from Excel worksheets.
Usage: $0 FILE [...]
EOF
}

if (( $# == 0 )); then
  usage
  exit 1
elif [[ "$1" =~ -h|--help|-help|help ]]; then
  usage
  exit 0
fi

unprotect() {

  set -eu

  local PREFIX EXTENSION

  EXTENSION="$(sed -E 's/.+\.//' <<< $FILENAME)"
  PREFIX="$(sed -E 's/(\.xlsx|\.xls)$//' <<< $FILENAME)"

  if ! [[ "$EXTENSION" =~ xlsx|xls ]]; then
    printf "Failed (not an Excel file)\n"
    return 1
  fi

  unzip -qd "$PREFIX" "$FILENAME"

  cd "$PREFIX"

  find "xl/worksheets" -maxdepth 1 -type f -regex ".+sheet[0-9]+\.xml" -exec sed -Ei 's/<sheetProtection[^>]+>//' {} \;

  zip -qr "../${PREFIX}.unprotected.${EXTENSION}" .

  cd ..

  rm -r "$PREFIX"

  set +eu

}

for FILENAME in "$@"; do

  printf "Processing %s...\t" "$FILENAME"

  unprotect "$FILENAME"

  EXIT_STATUS=$?

  if (( $EXIT_STATUS == 0 )); then
    printf "%s\n" "Success"
  else
    printf "%s (%d)\n" "Failed" $EXIT_STATUS
  fi

done