common/scripts/shtwitter.sh

#!/usr/bin/ksh93

#
# CDDL HEADER START
#
# The contents of this file are subject to the terms of the
# Common Development and Distribution License (the "License").
# You may not use this file except in compliance with the License.
#
# You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
# or http://www.opensolaris.org/os/licensing.
# See the License for the specific language governing permissions
# and limitations under the License.
#
# When distributing Covered Code, include this CDDL HEADER in each
# file and include the License file at usr/src/OPENSOLARIS.LICENSE.
# If applicable, add the following below this CDDL HEADER, with the
# fields enclosed by brackets "[]" replaced with your own identifying
# information: Portions Copyright [yyyy] [name of copyright owner]
#
# CDDL HEADER END
#

#
# Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
#

# Solaris needs /usr/xpg6/bin:/usr/xpg4/bin because the tools in /usr/bin are not POSIX-conformant
export PATH=/usr/xpg6/bin:/usr/xpg4/bin:/bin:/usr/bin

# Make sure all math stuff runs in the "C" locale to avoid problems
# with alternative # radix point representations (e.g. ',' instead of
# '.' in de_DE.*-locales). This needs to be set _before_ any
# floating-point constants are defined in this script).
if [[ "${LC_ALL}" != "" ]] ; then
    export \
        LC_MONETARY="${LC_ALL}" \
        LC_MESSAGES="${LC_ALL}" \
        LC_COLLATE="${LC_ALL}" \
        LC_CTYPE="${LC_ALL}"
        unset LC_ALL
fi
export LC_NUMERIC=C

function fatal_error
{
    print -u2 "${progname}: $*"
    exit 1
}

function encode_x_www_form_urlencoded
{
    nameref formdata=$1
    nameref content="formdata.content"
    integer numformelements=${#formdata.form[*]}
    integer i j

    content=""

    for (( i=0 ; i < numformelements ; i++ )) ; do
        nameref element="formdata.form[${i}]"
        typeset data="${element.data}"
        integer datalen="${#data}"
        typeset c

        [[ "$content" != "" ]] && content+="&"

        content+="${element.name}="

        for ((j=0 ; j < datalen ; j++)) ; do
            c="${data:j:1}"
            case "$c" in
                ' ') c="+"   ;;
                '!') c="%21" ;;
                '*') c="%2A" ;;
                "'") c="%27" ;;
                '(') c="%28" ;;
                ')') c="%29" ;;
                ';') c="%3B" ;;
                ':') c="%3A" ;;
                '@') c="%40" ;;
                '&') c="%26" ;;
                '=') c="%3D" ;;
                '+') c="%2B" ;;
                '$') c="%24" ;;
                ',') c="%2C" ;;
                '/') c="%2F" ;;
                '?') c="%3F" ;;
                '%') c="%25" ;;
                '#') c="%23" ;;
                '[') c="%5B" ;;
                '\') c="%5C" ;; # we need this to avoid the '\'-quoting hell
                ']') c="%5D" ;;
                *)   ;;
            esac
            content+="$c"
        done
    done

    formdata.content_length=${#content}

    return 0
}

# parse HTTP return code, cookies etc.
function parse_http_response
{
    nameref response="$1"
    typeset h statuscode statusmsg i

    # we use '\r' as additional IFS to filter the final '\r'
    IFS=$' \t\r' read -r h statuscode statusmsg  # read HTTP/1.[01] <code>
    [[ "$h" != ~(Eil)HTTP/.* ]]         && { print -u2 -f $"%s: HTTP/ header missing\n" "$0" ; return 1 ; }
    [[ "$statuscode" != ~(Elr)[0-9]* ]] && { print -u2 -f $"%s: invalid status code\n"  "$0" ; return 1 ; }
    response.statuscode="$statuscode"
    response.statusmsg="$statusmsg"

    # skip remaining headers
    while IFS='' read -r i ; do
        [[ "$i" == $'\r' ]] && break

        # strip '\r' at the end
        i="${i/~(Er)$'\r'/}"

        case "$i" in
            ~(Eli)Content-Type:.*)
                response.content_type="${i/~(El).*:[[:blank:]]*/}"
                ;;
            ~(Eli)Content-Length:[[:blank:]]*[0-9]*)
                integer response.content_length="${i/~(El).*:[[:blank:]]*/}"
                ;;
            ~(Eli)Transfer-Encoding:.*)
                response.transfer_encoding="${i/~(El).*:[[:blank:]]*/}"
                ;;
        esac
    done

    return 0
}

function cat_http_body
{
    typeset emode="$1"
    typeset hexchunksize="0"
    integer chunksize=0

    if [[ "${emode}" == "chunked" ]] ; then
        while IFS=$'\r' read hexchunksize &&
            [[ "${hexchunksize}" == ~(Elri)[0-9abcdef]+ ]] &&
            (( chunksize=$( printf "16#%s\n" "${hexchunksize}" ) )) && (( chunksize > 0 )) ; do
            dd bs=1 count="${chunksize}" 2>/dev/null
        done
    else
        cat
    fi

    return 0
}

function encode_http_basic_auth
{
    typeset user="$1"
    typeset passwd="$2"
    typeset s
    integer s_len
    typeset -b base64var

    # ksh93 binary variables use base64 encoding, the same as the
    # HTTP basic authentification. We only have to read the
    # plaintext user:passwd string into the binary variable "base64var"
    # and then print this variable as ASCII.
    s="${user}:${passwd}"
    s_len="${#s}"
    print -n "${s}" | read -N${s_len} base64var

    print -- "${base64var}" # print ASCII (base64) representation of binary var

    return 0
}

function put_twitter_message
{
    [[ "$SHTWITTER_USER"   == "" ]] && { print -u2 -f $"%s: SHTWITTER_USER not set.\n" "$0" ; return 1 ; }
    [[ "$SHTWITTER_PASSWD" == "" ]] && { print -u2 -f $"%s: SHTWITTER_PASSWD not set.\n" "$0" ; return 1 ; }

    (( $# != 1 )) && { print -u2 -f $"%s: Wrong number of arguments.\n" "$0" ; return 1 ; }

    # site setup
    typeset url_host="twitter.com"
    typeset url_path="/statuses/update.xml"
    typeset url="http://${url_host}${url_path}"
    integer netfd # http stream number
    typeset msgtext="$1"
    compound httpresponse # http response

    # argument for "encode_x_www_form_urlencoded"
    compound urlform=(
        # input
        compound -a form=(
            ( name="status" data="${msgtext}" )
        )
        # output
        typeset content
        integer content_length
    )

    typeset request=""
    typeset content=""

    encode_x_www_form_urlencoded urlform

    content="${urlform.content}"

    request="POST ${url_path} HTTP/1.1\r\n"
    request+="Host: ${url_host}\r\n"
    request+="Authorization: Basic ${ encode_http_basic_auth "${SHTWITTER_USER}" "${SHTWITTER_PASSWD}" ; }\r\n"
    request+="User-Agent: ${http_user_agent}\r\n"
    request+="Connection: close\r\n"
    request+="Content-Type: application/x-www-form-urlencoded\r\n"
    request+="Content-Length: $(( urlform.content_length ))\r\n"

    redirect {netfd}<> "/dev/tcp/${url_host}/80"
    (( $? != 0 )) && { print -u2 -f "%s: Could not open connection to %s\n." "$0" "${url_host}" ;  return 1 ; }

    # send http post
    {
        print -n -- "${request}\r\n"
        print -n -- "${content}\r\n"
    }  >&${netfd}

    # process reply
    parse_http_response httpresponse <&${netfd}
    response="${ cat_http_body "${httpresponse.transfer_encoding}" <&${netfd} ; }"

    # close connection
    redirect {netfd}<&-

    printf $"twitter response was (%s,%s): %s\n" "${httpresponse.statuscode}" "${httpresponse.statusmsg}" "${response}"

    if (( httpresponse.statuscode >= 200 && httpresponse.statuscode <= 299 )) ; then
        return 0
    else
        return 1
    fi

    # not reached
}

function verify_twitter_credentials
{
    [[ "$SHTWITTER_USER"   == "" ]] && { print -u2 -f $"%s: SHTWITTER_USER not set.\n" "$0" ; return 1 ; }
    [[ "$SHTWITTER_PASSWD" == "" ]] && { print -u2 -f $"%s: SHTWITTER_PASSWD not set.\n" "$0" ; return 1 ; }

    (( $# != 0 )) && { print -u2 -f $"%s: Wrong number of arguments.\n" "$0" ; return 1 ; }

    # site setup
    typeset url_host="twitter.com"
    typeset url_path="/account/verify_credentials.xml"
    typeset url="http://${url_host}${url_path}"
    integer netfd # http stream number
    compound httpresponse # http response

    typeset request=""

    request="POST ${url_path} HTTP/1.1\r\n"
    request+="Host: ${url_host}\r\n"
    request+="Authorization: Basic ${ encode_http_basic_auth "${SHTWITTER_USER}" "${SHTWITTER_PASSWD}" ; }\r\n"
    request+="User-Agent: ${http_user_agent}\r\n"
    request+="Connection: close\r\n"
    request+="Content-Type: application/x-www-form-urlencoded\r\n"
    request+="Content-Length: 0\r\n" # dummy

    redirect {netfd}<> "/dev/tcp/${url_host}/80"
    (( $? != 0 )) && { print -u2 -f $"%s: Could not open connection to %s.\n" "$0" "${url_host}" ;  return 1 ; }

    # send http post
    {
        print -n -- "${request}\r\n"
    }  >&${netfd}

    # process reply
    parse_http_response httpresponse <&${netfd}
    response="${ cat_http_body "${httpresponse.transfer_encoding}" <&${netfd} ; }"

    # close connection
    redirect {netfd}<&-

    printf $"twitter response was (%s,%s): %s\n" "${httpresponse.statuscode}" "${httpresponse.statusmsg}" "${response}"

    if (( httpresponse.statuscode >= 200 && httpresponse.statuscode <= 299 )) ; then
        return 0
    else
        return 1
    fi

    # not reached
}

function usage
{
    OPTIND=0
    getopts -a "${progname}" "${shtwitter_usage}" OPT '-?'
    exit 2
}

# program start
builtin basename
builtin cat
builtin date
builtin uname

typeset progname="${ basename "${0}" ; }"

# HTTP protocol client identifer
typeset -r http_user_agent="shtwitter/ksh93 (2010-03-27; ${ uname -s -r -p ; })"

typeset -r shtwitter_usage=$'+
[-?\n@(#)\$Id: shtwitter (Roland Mainz) 2010-03-27 \$\n]
[-author?Roland Mainz <roland.mainz@nrubsig.org>]
[+NAME?shtwitter - read/write text data to internet clipboards]
[+DESCRIPTION?\bshtwitter\b is a small utility which can read and write text
    to the twitter.com microblogging site.]
[+?The first arg \bmethod\b describes one of the methods, "update" posts a
    text message to the users twitter blog, returning the raw response
    message from the twitter server.]
[+?The second arg \bstring\b contains the string data which should be
    stored on twitter.com.]

method [ string ]

[+SEE ALSO?\bksh93\b(1), \brssread\b(1), \bshtinyurl\b(1), http://www.twitter.com]
'

while getopts -a "${progname}" "${shtwitter_usage}" OPT ; do
#   printmsg "## OPT=|${OPT}|, OPTARG=|${OPTARG}|"
    case ${OPT} in
        *)  usage ;;
    esac
done
shift $((OPTIND-1))

# expecting at least one more argument
(($# >= 1)) || usage

typeset method="$1"
shift

case "${method}" in
    update|blog)        put_twitter_message        "$@" ; exit $? ;;
    verify_credentials) verify_twitter_credentials "$@" ; exit $? ;;
    *)          usage ;;
esac

fatal_error $"not reached."
# EOF.