#!/bin/sh
#
# lsb_release - collect LSB conformance status about a system
#
# Copyright (C) 2000, 2002, 2004 Free Standards Group, Inc.
# Originally by Dominique MASSONIE <mdomi@users.sourceforge.net>
# Modified for SUSE Linux products by Thorsten Kukuk
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
# General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
#
# Description:
# Collect information from sourceable /etc/lsb-release file (present on
# LSB-compliant systems) : LSB_VERSION, DISTRIB_ID, DISTRIB_RELEASE,
# DISTRIB_CODENAME, DISTRIB_DESCRIPTION (all optional)
# Then (if needed) find and add names from /etc/lsb-release.d


###############################################################################
#     DECLARATIONS
###############################################################################

# This script version
SCRIPTVERSION="3.1-eisfair"

# Defines the data files
INFO_LSB_FILE="/etc/lsb-release"              # where to get LSB version
INFO_LSB_DIR="/etc/lsb-release.d"             # where to get LSB addon modules
INFO_DISTRIB_FILE="/etc/os-release"           # <distrib>-<suffix>

# Defines our exit codes
EXIT_STATUS="0"                           # default = Ok :)
ERROR_UNKNOWN="10"                        # unknown error
ERROR_USER="1"                            # program misuse
ERROR_PROGRAM="2"                         # internal error
ERROR_NOANSWER="3"                        # all required info not available
                                          # typically non LSB compliant distro!

# Defines our messages
MSG_LSBVER="LSB Version:\t"
MSG_DISTID="Distributor ID:\t"
MSG_DISTDESC="Description:\t"
MSG_DISTREL="Release:\t"
MSG_DISTCODE="Codename:\t"
MSG_NA="n/a"
MSG_NONE="(none)"
MSG_RESULT="" # contains the result in case short output selected
MSG_DISTRIBUTOR="eisfair project"

###############################################################################
#     FUNCTIONS
###############################################################################

# Display Program Version for internal use (needed by help2man)
DisplayProgramVersion() {
    echo "`basename $0` v$SCRIPTVERSION"
    echo
    echo "Copyright (C) 2000, 2002, 2004 Free Standards Group, Inc."
    echo
    echo "This is free software; see the source for copying conditions.  There is NO"
    echo "warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE."
    echo
    echo "Originally written by Dominique MASSONIE."

    exit $EXIT_STATUS
}

# defines the Usage for lsb_release
Usage() {
    echo "`basename $0` v$SCRIPTVERSION prints certain LSB (Linux Standard Base) and"
    echo "Distribution information."
    echo
    echo "Usage: `basename $0` [OPTION]..."
    echo "With no OPTION specified defaults to -v."
    echo
    echo "Options:"
    echo "  -v, --version"
    echo "    Display the version of the LSB specification against which the distribution is compliant."
    echo "  -i, --id"
    echo "    Display the string id of the distributor."
    echo "  -d, --description"
    echo "    Display the single line text description of the distribution."
    echo "  -r, --release"
    echo "    Display the release number of the distribution."
    echo "  -c, --codename"
    echo "    Display the codename according to the distribution release."
    echo "  -a, --all"
    echo "    Display all of the above information."
    echo "  -s, --short"
    echo "    Use short output format for information requested by other options (or version if none)."
    echo "  -h, --help"
    echo "    Display this message."

    exit $EXIT_STATUS
}

# Handles the enhanced args (i.e. --something)
EnhancedGetopt() {
    getopt -T >/dev/null 2>&1             # is getopt the enhanced one ?
    if [ $? = 4 ]
    then                                  # Yes, advanced args ALLOWED
        OPT=$(getopt -o acdhirsvp                                             \
--long all,codename,description,help,id,release,short,version,program_version \
              -n 'lsb_release'                                                \
              -- "$@")
    else                                  # No, advanced args NOT allowed
        # convert (if needed) the enhanced options into basic ones
        MYARGS=$(echo "$@" | sed -e "/--/s/-\(-[[:alnum:]]\)[[:alnum:]]*/\1/g")
        OPT=$(getopt -o acdhirsvp                                             \
                     -n 'lsb_release'                                         \
                     -- "$MYARGS")
    fi
    if [ $? != 0 ]
    then
        exit $ERROR_PROGRAM
    fi

    NB_ARG=""       # enabled if many args set in one parameter (i.e. -dris)
    eval set -- "$OPT"
    while true ; do
        case "$1" in
        -a|--all) ARG_A="y"; NB_ARG="y"; shift;;
        -c|--codename) ARG_C="y"; NB_ARG="y"; shift;;
        -d|--description) ARG_D="y"; NB_ARG="y"; shift;;
        -i|--id) ARG_I="y"; NB_ARG="y"; shift;;
        -r|--release) ARG_R="y"; NB_ARG="y"; shift;;
        -s|--short) ARG_S="y"; shift;;
        -v|--version) ARG_V="y"; NB_ARG="y"; shift;;
        -p|--program_version) DisplayProgramVersion;;
        -h|--help) Usage;;
        --) shift; break;;
        *)  EXIT_STATUS=$ERROR_USER
            Usage;;
        esac
    done
}


# Get/Init LSB infos (maybe Distrib infos too)
GetLSBInfo() {
    LSB_VERSION=""
    if [ -f "$INFO_LSB_FILE" ]
    then
        # should init at least LSB_VERSION
        . "$INFO_LSB_FILE"
    fi
    # Always look in the directories
    if [ -d "$INFO_ROOT/$INFO_LSB_DIR" ]
    then
	for tag in "$INFO_ROOT/$INFO_LSB_DIR/"*
	do
	    if [ -z "$LSB_VERSION" ]
	    then
		LSB_VERSION=`basename $tag`
	    else
		LSB_VERSION=$LSB_VERSION:`basename $tag`
	    fi
	done
    fi
    if [ -z "$LSB_VERSION" ]
    then
	LSB_VERSION=$MSG_NA
    fi
}

# Get the whole distrib information string (from /etc/os-release)
InitDistribInfo() {

    source $INFO_DISTRIB_FILE
    NO=""                    # is Description string syntax correct ?

    if [ -z "$DISTRIB_DESCRIPTION" ]; then
	if [ -n "$PRETTY_NAME" ]; then
            DISTRIB_DESCRIPTION=$PRETTY_NAME
	else
            DISTRIB_DESCRIPTION=$MSG_NONE
	fi
    fi

    if [ -z "$DISTRIB_ID" ]; then
	if [ -n "$MSG_DISTRIBUTOR" ]; then
	    DISTRIB_ID=$MSG_DISTRIBUTOR
	else
	    case "$PRETTY_NAME" in
		openSUSE*)
		    DISTRIB_ID="openSUSE"
		    ;;
		SUSE*)
		    DISTRIB_ID="SUSE"
		    ;;
		*)
		    DISTRIB_ID=$MSG_NA
		    ;;
	    esac
	fi
    fi

    if [ -z "$DISTRIB_RELEASE" ]; then
	if [ -n "$VERSION_ID" ]; then
            DISTRIB_RELEASE=$VERSION_ID
	else
            DISTRIB_RELEASE=$MSG_NA
	fi
    fi

    if [ -z "$DISTRIB_CODENAME" ]; then
	if [ -n "$VERSION_CODENAME" ]; then
            DISTRIB_CODENAME = $VERSION_CODENAME
	else
            DISTRIB_CODENAME=$MSG_NA
	fi
    fi
}

# Check missing and requested infos, then find the file and get infos
GetDistribInfo() {
    NO=""  # /etc/lsb-release data are enough to reply what is requested?
    [ -n "$ARG_D" ] && [ -z "$DISTRIB_DESCRIPTION" ] && NO="y"
    [ -z "$NO" ] && [ -n "$ARG_I" ] && [ -z "$DISTRIB_ID" ] && NO="y"
    [ -z "$NO" ] && [ -n "$ARG_R" ] && [ -z "$DISTRIB_RELEASE" ] && NO="y"
    [ -z "$NO" ] && [ -n "$ARG_C" ] && [ -z "$DISTRIB_CODENAME" ] && NO="y"

    if [ -n "$NO" ]
    then
        InitDistribInfo
    fi
}

# Display version of LSB against which distribution is compliant
DisplayVersion() {
    if [ -z "$ARG_S" ]
    then
        echo -e "$MSG_LSBVER$LSB_VERSION"          # at least "n/a"
    else
        MSG_RESULT="$MSG_RESULT${MSG_RESULT:+ }$LSB_VERSION"
    fi
}

# Display string id of distributor ( i.e. a single word! )
DisplayID() {
    if [ -z "$ARG_S" ]
    then
        echo -e "$MSG_DISTID$DISTRIB_ID"
    else
        MSG_RESULT="$MSG_RESULT${MSG_RESULT:+ }$DISTRIB_ID"
    fi
}

# Diplay single line text description of distribution
DisplayDescription() {
    if [ -z "$DISTRIB_DESCRIPTION" ]
    then
        # should not be empty since GetDistribInfo called on Initialization !
        EXIT_STATUS=$ERROR_PROGRAM
    fi
    if [ -z "$ARG_S" ]
    then
        echo -e "$MSG_DISTDESC$DISTRIB_DESCRIPTION"
    else
        MSG_RESULT="$MSG_RESULT${MSG_RESULT:+ }$DISTRIB_DESCRIPTION"
    fi
}

# Display release number of distribution.
DisplayRelease() {
    if [ -z "$ARG_S" ]
    then
        echo -e "$MSG_DISTREL$DISTRIB_RELEASE"
    else
        MSG_RESULT="$MSG_RESULT${MSG_RESULT:+ }$DISTRIB_RELEASE"
    fi
}

# Display codename according to distribution version.
DisplayCodename() {
    if [ -z "$ARG_S" ]
    then
        echo -e "$MSG_DISTCODE$(echo "$DISTRIB_CODENAME" |                    \
                                tr -d "[:blank:]")" # Remove blanks
    else
        MSG_RESULT="$MSG_RESULT${MSG_RESULT:+ }$(echo "$DISTRIB_CODENAME" |   \
                                                 tr -d "[:blank:]")"
    fi
}


###############################################################################
#     MAIN
###############################################################################

# Check if any prog argument
if [ -z "$1" ]
then
    ARG_V="y"           # default set to Display LSB Version (not Usage)
else
    EnhancedGetopt "$@" # Parse program args
    if [ -n "$ARG_S" ] && [ -z "$NB_ARG" ]
    then
        ARG_V="y"       # set also default for --short when single arg
    fi
fi

# Update args to All if requested
if [ -n "$ARG_A" ]
then
    [ -z "$ARG_C" ] && ARG_C="y"
    [ -z "$ARG_D" ] && ARG_D="y"
    [ -z "$ARG_I" ] && ARG_I="y"
    [ -z "$ARG_R" ] && ARG_R="y"
    [ -z "$ARG_V" ] && ARG_V="y"
fi

# Initialization
GetLSBInfo
GetDistribInfo

# Display requested infos (order as follow)
[ -n "$ARG_V" ] && DisplayVersion
[ -n "$ARG_I" ] && DisplayID
[ -n "$ARG_D" ] && DisplayDescription
[ -n "$ARG_R" ] && DisplayRelease
[ -n "$ARG_C" ] && DisplayCodename

[ -n "$ARG_S" ] && echo "$MSG_RESULT"

exit $EXIT_STATUS