Write a bash script called extract which can unpack multiple packed files, and even traverse folders recursively and unpack all archives in them - regardless of the specific algorithm that was used when packing them. Following is the exact synopsis: extract [-h] [-r] [-v] file [file...] Given a list of filenames as input, this script queries each target file (parsing the output of the file command) for the type of compression used on it. Then the script automatically invokes the appropriate decompression command, putting files in the same folder. If files with the same name already exist, they are overwritten. Unpack should support 4 unpacking options - gunzip, bunzip2, unzip, uncompress. Adding more options should be VERY simple. Note that file names and extensions have no meaning - the only way to know what method to use is through the file command! If a target file is not compressed, the script takes no other action on that particular file. If the target is a directory then it decompresses all files in it using same method. Command echos number of archives decompressed Command returns number of files it did NOT decompress Additional switches:
- v - verbose - echo each file decompressed & warn for each file that was NOT decompressed
- r - recursive - will traverse contents of folders recursively, performing unpack on each.
- h - should receive a HELP notice
#!/bin/bash
# Colourise the output
RED='\033[0;31m' # Red
GRE='\033[0;32m' # Green
YEL='\033[1;33m' # Yellow
NCL='\033[0m' # No Color
# Perform unpacking
unpack() {
FILE_NAME="$(basename "${entry}")"
FILE_TYPE="$(file -i "${entry}")"
SIZE="$(du -sh "${entry}" | cut -f1)"
if $VERBOSE_FLAG ; then
printf "%*s${GRE}%s${NCL}\n" $((indent+4)) '' "${entry}"
printf "%*s\tFile type:\t${YEL}%s${NCL}\n" $((indent+4)) '' "${FILE_TYPE#*: }"
printf "%*s\tFile size:\t${YEL}%s${NCL}\n" $((indent+4)) '' "$SIZE"
fi
DECOMPRESSED="Can not be extracted"
case "${FILE_TYPE}" in
**application/x-bzip2*) bunzip2 "${entry}" && ((++TOTAL_DECOMPRESSED)) && DECOMPRESSED="Extracted" || ((++TOTAL_UNCOMPRESSED)) ;;
*application/gzip*) gunzip "${entry}" && ((++TOTAL_DECOMPRESSED)) && DECOMPRESSED="Extracted" || ((++TOTAL_UNCOMPRESSED)) ;;
*application/zip*) unzip -o -qq -d $(dirname $entry) "${entry}" && ((++TOTAL_DECOMPRESSED)) && DECOMPRESSED="Extracted" && rm $entry || ((++TOTAL_UNCOMPRESSED)) ;;
*application/x-compress*) uncompress "${entry}" && ((++TOTAL_DECOMPRESSED)) && DECOMPRESSED="Extracted" || ((++TOTAL_UNCOMPRESSED)) ;;
*) ((TOTAL_UNCOMPRESSED++)) ;;
esac
$VERBOSE_FLAG && printf "%*s\tExtracted:\t${YEL}%s${NCL}\n" $((indent+4)) '' "${DECOMPRESSED}"
}
# Directory traversal
walk() {
local indent="${2:-0}"
$VERBOSE_FLAG && printf "\n%*s${RED}%s${NCL}\n\n" "$indent" '' "$1"
# If the entry is a file do unpack
for entry in "$1"/*; do [[ -f "$entry" ]] && unpack; done
# If the entry is a directory and recursive option is enabled make a recursive call
for entry in "$1"/*; do [[ -d "$entry" ]] && $RECURSIVE_FLAG && walk "$entry" $((indent+4)); done
}
PARAMS=""
VERBOSE_FLAG=false
HELP_FLAG=false
RECURSIVE_FLAG=false
TOTAL_DECOMPRESSED=0
TOTAL_UNCOMPRESSED=0
# Extract options
while (( "$#" )); do
case "$1" in
-v|--verbose)
VERBOSE_FLAG=true
shift
;;
-h|--help)
HELP_FLAG=true
shift
;;
-r|--recursive)
RECURSIVE_FLAG=true
shift
;;
-*|--*=) # Unsupported flags
echo "Error: Unsupported flag $1" >&2
exit 1
;;
*) # Preserve positional arguments
PARAMS="$PARAMS $1"
shift
;;
esac
done
# Show help
if $HELP_FLAG ; then
echo "Usage: extract.sh [OPTION]... [FILE]...
Extracts multiple packed files, and even traverse folders recursively and unpack all archives in them - regardless of the specific algorithm that was used when packing them.
Given a list of filenames as input, this script queries each target file for the type of compression used on it.
Then the script automatically invokes the appropriate decompression command, putting files in the same folder.
If files with the same name already exist, they are overwritten.
Script supports 4 unpacking options - gunzip, bunzip2, unzip, uncompress.
If a target file is not compressed, the script takes no other action on that particular file.
If the target is a directory then it decompresses all files in it using same method.
Script returns number of archives decompressed.
Command returns number of files it did NOT decompress.
Additional switches:
-v (--verbose) - verbose - returns each file decompressed & warn for each file that was NOT decompressed
-r (--recursive) - traverses contents of folders recursively, performing unpack on each
-h (--help) - this HELP notice"
exit 0
fi
# Set positional arguments in their proper place
eval set -- "$PARAMS"
# Process files and directories from positional arguments
if [ $# -eq 0 ]; then
EXEC_DIR="${PWD}"
walk "${EXEC_DIR}"
else
for FILE in "${@}"
do
if [[ -d $FILE ]] ; then
if [[ $FILE == /* ]] ; then
EXEC_DIR="${FILE}"
else
EXEC_DIR="${PWD}/${FILE}"
fi
walk "${EXEC_DIR}"
else
entry=$FILE
unpack
fi
done
fi
echo
printf "Total extracted:\t${YEL}%s${NCL}\n" "${TOTAL_DECOMPRESSED}"
printf "Total not extracted:\t${YEL}%s${NCL}\n" "${TOTAL_UNCOMPRESSED}"