#!/bin/sh
# untar --- extract contents of archive files into a single directory
# Author: Noah Friedman <friedman@splode.com>
# Created: 1996-01-15
# Public domain

# $Id: untar,v 1.41 2019/08/01 19:26:33 friedman Exp $

# Commentary:

# This started out just unpacking tar files, but now supports more formats.

# Code:

tmpdir=untar$$

pre()
{
    pkgdir=`echo "$file" | sed -e 's=.*/==' -e 's=\.[^.]*$=='`
    case $pkgdir in
        *.tar | *.xtar ) pkgdir=`echo "$pkgdir" | sed -e 's=\.[^.]*$=='` ;;
    esac

    if [ -d "$pkgdir" ]; then
        echo "$pkgdir": directory already exists 1>&2
        return 1
    fi

    if [ -d "$tmpdir" ]; then
        echo "$tmpdir": temp directory already exists, and it shouldn\'t 1>&2
        return 1
    fi

    mkdir -p "$tmpdir" || return 1
    cd       "$tmpdir" || return 1

    case $file in
        /* ) : ;;
        *  ) file=../$file ;;
    esac

    return 0
}

post()
{
    nfiles=`ls -1A | wc -l`

    ndir=
    if [ $nfiles -eq 1 ]; then
        ndir=`ls -1A`
    fi

    if   [ $nfiles -gt 1 ] ||
       { [ $nfiles -eq 1 ] && [ ".$ndir" != ".$pkgdir" ]; }
    then
        cd .. &&
        mv "$tmpdir" "$pkgdir"
    elif [ $nfiles -eq 1 ]; then
        mv "$ndir" .. &&
        cd .. &&
        rmdir "$tmpdir"
    else
        echo "$tmpdir": empty directory\? 1>&2
        cd .. && rmdir "$tmpdir"
        return 1
    fi
}

extract()
{
    case $file in
        *.t[ag]z | *.tar.gz | *.tar.[Zz] | *.xtar.gz | *.xtar.[Zz] | *.nif )
            ${GZIP-gzip} -dc "$file" | ${TAR-tar} -xpvf - ;;

        *.tbz | *.tbz2 | *.tar.bz2 | *.xtar.bz2 | *.tar.bz | *.cbt )
            ${BZIP2-bzip2} -dc "$file" | ${TAR-tar} -xpvf - ;;

        *.tar.xz | *.txz ) # xz uses LZMA, but isn't compatible with `lzma'
            ${XZ-xz} -dc "$file" | ${TAR-tar} -xpvf - ;;

        *.tar.lz | *.tlz ) # lzip uses LZMA, but isn't compatible with `lzma'
            ${LZIP-lzip} -dc "$file" | ${TAR-tar} -xpvf - ;;

        *.tar.lzma )
            ${LZMA-lzma} -dc "$file" | ${TAR-tar} -xpvf - ;;

        *.tar | *.xtar | *.ova | *.tar.md5 )
            ${TAR-tar} -xpvf "$file" ;;

        *.zip | *.cbz | *.fbu | *.jar | *.apk | *.xpi | *.epub )
            ${UNZIP-unzip} -o -d . "$file" ;;

        *.rpm )
            ${RPM2CPIO-rpm2cpio} "$file" | ${CPIO-cpio} -dimv --no-absolute-filenames ;;

        *.deb | *.udeb )
            ${AR-ar} xv "$file"
            for file in control.tar.* data.tar.* ; do
                (pre; extract; post)
                rm -f "$file"
            done ;;

        *.lzh )
            ${LHA-lha} x "$file" ;;

        *.rar | *.cbr )
            if type unar >/dev/null 2>&1;
            then : ${UNRAR:=unar}
            else : ${UNRAR:=unrar}
            fi
            case $UNRAR in
                *unar  ) $UNRAR -t "$file" ;;
                *unrar ) $UNRAR x "$file" ;;
            esac ;;

        *.a | *.lib )
            ${AR-ar} t "$file" | sed -ne 's=/[^/]*$==p' |
                xargs --no-run-if-empty mkdir -p
            ${AR-ar} xv "$file" ;;

        *.7z )
            7z x "$file" ;;

        *.cab )
            #${CABEXTRACT-cabextract} "$file" ;;
            7z x "$file" ;;

        *.msi )
            # ${MSIEXEC-msiexec} /a "$file" /qb TARGETDIR=./$pkgdir ;;
            7z x "$file" ;;

        *.dmg )
            7z x "$file" ;;

        *.pkg ) # mac pkg files
            # pkgutil --expand "$file" .
            basename=${file##*/}
            pkgdir=${basename%.pkg}.app
            7z x -o"$pkgdir" "$file" ;;

        *initramfs*.img | *initrd*.img | *ramdisk.img )
            extract_initrd "$file" ;;

        *.squashfs )
            dest=${file##*/}
            unsquashfs -i -d "${dest%.squashfs}" "$file" ;;

        *.iso )
            xorriso -for_backup \
                    -indev "$file" \
                    -osirrox on:auto_chmod_on \
                    -chmod_r u+rw / -- \
                    -extract / .  \
                    -rollback_end
            ;;
    esac
}

extract_initrd()
{
    if ${GREP-grep} -q 'early_cpio' "$file"; then
        # Skip uncompressed cpu microcode blobs at head of actual archive.
        blocks=`${CPIO-cpio} -t < "$file" 2>&1 \
                  | sed -ne '/^\([0-9]*\) blocks$/s//\1/p'`
        exp() { ${DD-dd} bs=1b skip=$blocks status=none if="$1"; }
    else
        exp() { ${CAT-cat} -- "$1"; }
    fi

    kind=`exp "$file" | file -`
    case $kind in
        *gzip*  ) exp2() { ${GZIP-gzip}   -dc; } ;;
        *bzip2* ) exp2() { ${BZIP2-bzip2} -dc; } ;;
        *XZ*    ) exp2() { ${XZ-xz}       -dc; } ;;
        *cpio*  ) exp2() { ${CAT-cat};         } ;;
        *       ) echo "$file: unknown file format" 1>&2
                  exit 1 ;;
    esac
    exp "$file" | exp2 | ${CPIO-cpio} -dimv --no-absolute-filenames
}


main()
{
  for file in ${1+"$@"}; do
    (pre; extract; post)
  done
}

main ${1+"$@"}

# eof