mime

#! /bin/sh

# mime2ext(1): maps MIME types to file extensions
#
# Yves Arrouye

: ${TMPDIR:=/tmp}
me=`basename $0`

default_MIMETYPES1=/etc/apache2/mime.types
default_MIMETYPES2=/usr/share/cups/mime/mime.types
if [ -f "$default_MIMETYPES1" ]
then
    default_MIMETYPES=$default_MIMETYPES1
else
    if [ -f "$default_MIMETYPES2" ]
    then
        default_MIMETYPES=$default_MIMETYPES2
    else
        default_MIMETYPES=
    fi
fi

usage() {
    if [ "$1" -eq 0 ]
    then
        u=U
    else
        u=u
        exec >&2
    fi
    echo $u"sage: $me [--help] [--mime-types file] [-g, --guess] [-C] [-E] [-h | --no-filename] [-m glob-pattern] [file ...]"
    if [ "$1" -eq 0 ]
    then
	if [ -n "$default_MIMETYPES" ]
	then
	    ordefmimetypesmsg=" or $default_MIMETYPES1 or $default_MIMETYPES2"
	fi
        cat <<EOF

       --help                Show this message
       --mime-types file     Use given file to map MIME types to file extensions (defaults to \$MIMETYPES$ordefmimetypesmsg)
       -g, --guess           Double guess/check some broad MIME types
       -C                    Do not print charset information
       -E                    Do not print file extensions
       -h, --no-filename     Do not print filename
       -m glob-pattern       Exit with 0 if the base MIME type matches glob-pattern for all files, with 1 otherwise

EOF
    fi
    exit $1
}

while [ $# -ne 0 ]
do
    case "$1" in
        -[^-]*)
	    for l in `echo $1 | sed -e 's/^-//' -e 's/\(.\)/\1 /g'`
	    do
	        case "$l" in
		    g)
			guess=yes
			;;
		    C)
			nocharset=yes
			;;
		    E)
			nofileexts=yes
			;;
		    h)
			nofilename=yes
			;;
		    m)
			if [ $# -lt 2 ]
			then
			    usage 1
			fi
			shift
			pattern=$1
			;;
		    *)
			usage 1
			;;
		esac
	    done
	    ;;
	--help)
	    usage 0
	    ;;
	--mime-types)
	    if [ $# -lt 2 ]
	    then
		usage 1
	    fi
	    shift
	    MIMETYPES=$1
	    ;;
	--guess)
	    guess=yes
	    ;;
	--no-filename)
	    nofilename=yes
	    ;;
	--*)
	    usage 1
	    ;;
	*)
	    break
	    ;;
    esac
    shift
done

if [ -n "$MIMETYPES" -o -f "$default_MIMETYPES" ]
then
    : ${MIMETYPES:=$default_MIMETYPES}
    if [ ! -r "$MIMETYPES" ]
    then
	>&2 echo "$me: cannot open MIME types file: $MIMETYPES"
  	exit 2
    fi
fi

if [ $# -eq 0 ]
then
    extrain=-
fi

res=0

for infile in "$@" $extrain
do
    infile=${infile--}
    if [ "$infile" = - ]
    then
	tmpfile=`mktemp $TMPDIR/$me.XXXXXX`
	trap "rm -f $tmpfile 2>/dev/null" 0
	cat >$tmpfile
	infile=$tmpfile
    fi

    fullmimetype=`file -bI $infile`
    if [ -n "$guess" ]
    then
	case "$fullmimetype" in
	    text/plain*)
		replmimetype=
		if head -1 $infile | grep -q '^[ 	]*[{[]'
		then
		    replmimetype=application/json
		else
		    if head -1 $infile | grep -q '^HTTP/[0-9][0-9]*\.[0-9][0-9]* [0-9][0-9]*'
		    then
			replmimetype=text/x-http
		    fi
		fi
		if [ -n "$replmimetype" ]
		then
		    escreplmimetype=`echo $replmimetype | sed 's,/,\\\\/,g'`
		    fullmimetype=`echo "$fullmimetype" | sed "s,^text/plain,$escreplmimetype,"`
		fi
		;;
	esac
    fi
    mimetype=`echo $fullmimetype | sed 's/;.*$//'`

    if [ -r "$MIMETYPES" -a -z "$nofileexts" ]
    then
	mimeerrormsg="cannot find MIME type in $MIMETYPES"
	fileexts=`sed -n "s,^$mimetype"'[^a-z0-9]*\(.*\).*,\1,p' $MIMETYPES | sed 's/[a-z0-9]*(.*//'`
    else
	mimeerrormsg="cannot determine extension for MIME type"
	case $mimetype in
	    text/html)
		fileexts=html htm
		;;
	    text/plain)
		fileexts=txt
		;;
	esac
    fi

    if [ -n "$nofileexts" ]
    then
	fileexts=
    else
	fileexts="	$fileexts"
    fi

    if [ -z "$pattern" ]
    then
	if [ $# -gt 1 -a -z "$nofilename" ]
	then
	    header="$infile:"
	else
	    header=
	fi
	if [ -z "$nocharset" ]
	then
	    printmimetype=$fullmimetype
	else
	    printmimetype=$mimetype
	fi
	echo "$header$printmimetype$fileexts"
    else
	case "$mimetype" in
	    $pattern)
		;;
	    *)
		res=1
		;;
	esac
    fi

    if [ -f "$tmpfile" ]
    then
	rm -f $tmpfile
    fi

    if [ $res -eq 1 ]
    then
	break
    fi
done

exit $res