#!/bin/bash

#

# pppd.sh -- This functionality parses /var/log/messages and returns

# time reports for pppd.

#

# Copyright (C) 2012 Alain Reguera Delgado

#

# 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, write to the Free Software

# Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

#

# ----------------------------------------------------------------------

# $Id$

# ----------------------------------------------------------------------

function pppd {

    local MESSAGES_PATH=''

    local ENTRY=''

    local ENTRY_ID=''

    local ENTRIES=''

    local ENTRIES_IDS=''

    local INTERFACE=""

    local INTERFACES_REGEX=""

    # Initizalice the flags used in this functionality.

    local FLAG_INTERFACES=''

    local FLAG_MONTH=$(LANG=C;date | gawk '{print $2}')

    local FLAG_FIRSTDAY=$(LANG=C;date | gawk '{print $3}')

    local FLAG_LASTDAY=${FLAG_FIRSTDAY}

    # Interpret arguments and options passed through command-line.

    pppd_getOptions

    # Be sure the first day isn't greater than the last day used. In

    # case it does, use the last day value as first day value.

    # Otherwise no record would be output.

    if [[ $FLAG_FIRSTDAY > $FLAG_LASTDAY ]];then

        FLAG_FIRSTDAY=$FLAG_LASTDAY

    fi

    # Define absolute path to log messages.

    MESSAGES_PATH='/var/log/messages*'

    # Store log messages for later processing. Because messages

    # required root privilages it is necessary to make a sudo action

    # to read it. To avoid doing sudo actions constantly agains the

    # same file, make just one sudo action to read the log messages

    # and store the result in order for all other commands to be able

    # read the information. Also, it is convenient to work with a

    # unique source information instance from begining to end.

    MESSAGES=$(sudo cat ${MESSAGES_PATH} \

        | gawk '{if ($5 ~ /^pppd\[[0-9]+]:$/ \

            && $1 == "'${FLAG_MONTH}'" \

            && $2 >= '${FLAG_FIRSTDAY}' \

            && $2 <= '${FLAG_LASTDAY}') print $0 }')

    # Be sure the interface isn't an empty value. When no interface

    # value is passed as argument to this function, use `ppp0'

    # interface as default value.

    if [[ ! $FLAG_INTERFACES ]];then

        FLAG_INTERFACES="ppp0"

    fi

    # Be sure the interface meets the correct format. When a malformed

    # interface is passed as first argument to this function, use

    # `ppp0' interface as default value.

    for INTERFACE in $FLAG_INTERFACES;do

        if [[ $INTERFACE =~ '^ppp[0-9]$' ]];then

            INTERFACE_REGEX="${INTERFACE_REGEX}${INTERFACE}|"

        else

            continue

        fi

    done

    # Build regular expression pattern to match interfaces passed as

    # argument to pppd function.

    INTERFACE_REGEX=$(echo $INTERFACE_REGEX | sed -r 's/\|$//')

    INTERFACE_REGEX="(${INTERFACE_REGEX})"

    # Execute action names based on whether they were provided or not.

    if [[ $ACTIONNAMS == '' ]];then

        # When action names are not provided, define action names that

        # will take place, explicitly. This is the default behaviour.

        return

    else

        # When action names are provided, loop through them and

        # execute them one by one.

        for ACTIONNAM in $ACTIONNAMS;do

            # Excecute action name.

            ${CLI_SUBFUNC}_${ACTIONNAM}

        done

    fi

}