#! /bin/sh
# #############################################################################

       NAME_="okurl"
       HTML_="validate url links"
    PURPOSE_="validate a list of urls for their existence"
   SYNOPSIS_="$NAME_ [-hml] -i <url_list>"
   REQUIRES_="standard GNU commands, curl"
    VERSION_="1.0"
       DATE_="2004-06-17; last update: 2004-06-22"
     AUTHOR_="Dawid Michalczyk <dm@eonworks.com>"
        URL_="www.comp.eonworks.com"
   CATEGORY_="www"
   PLATFORM_="Linux"
      SHELL_="bash"
 DISTRIBUTE_="yes"

# #############################################################################
# This program is distributed under the terms of the GNU General Public License

usage () {

echo >&2 "$NAME_ $VERSION_ - $PURPOSE_
Usage: $SYNOPSIS_
Requires: $REQUIRES_
Options:
     -i, file with url addresses; one url per line
     -h, usage and options (this help)
     -l, see this script"
exit 1
}

# args check
[ $# -eq 0 ] && { echo >&2 missing argument, type $NAME_ -h for help; exit 1; }

# tmp file set up
tmp_1=/tmp/tmp.${RANDOM}$$

# signal trapping and tmp file removal
trap 'rm -f $tmp_1 >/dev/null 2>&1' 0
trap "exit 1" 1 2 3 15

# var init
inputf=

# options and arg handling
while getopts hli: options; do

    case $options in

        i) inputf=$OPTARG ;;
        h) usage ;;
        l) more $0; exit 1 ;;
       \?) echo invalid argument, type $NAME_ -h for help; exit 1 ;;

    esac

done
shift $(( $OPTIND - 1 ))

# check if command is in $PATH variable
which curl &> /dev/null
[[ $? != 0 ]] && { echo >&2 the required command \"curl\" is not in your path; exit 1; }

# does input file exist
[ ! -f $inputf ] && { echo >&2 $inputf does not exist, exiting; exit 1; }

http_response() {

    # check http response code
    response=$(sed -n -e 's/\o015//' -e '1p' < $1)
    code=$(echo $response | { read prot code msg; echo $code; })
    if [[ $code != 200 ]];then
        echo "$response (when accessing) $2"
        continue
    fi

}

curl_exit_status() {

    # if curl gives none 0 exit code
    if [[ $1 != 0 ]];then
        echo "curl exited with code ${1}, when accessing: $2 (man curl for info on exit codes)"
        continue
    fi

}

# main
while read line;do

    curl -sI --connect-timeout 120 ${line} -o $tmp_1 # getting the HTTP header
    curl_exit_status $? $line
    http_response $tmp_1 $line

done < $inputf