<?php
    /*
     * File: smtp.php
     *
     * Description: Define an SMTP class that can be used to connect
     *              and communicate with any SMTP server. It implements
     *              all the SMTP functions defined in RFC821 except TURN.
     *
     * Creator: Chris Ryan <chris@greatbridge.com>
     * Created: 03/26/2001
     *
     * TODO:
     *     - Move all the duplicate code to a utility function
     *           Most of the functions have the first lines of
     *           code do the same processing. If this can be moved
     *           into a utility function then it would reduce the
     *           overall size of the code significantly.
     */

    /*
     * STMP is rfc 821 compliant and implements all the rfc 821 SMTP
     * commands except TURN which will always return a not implemented
     * error. SMTP also provides some utility methods for sending mail
     * to an SMTP server.
     */
    class Util_Mail_Smtp {
        var $SMTP_PORT = 25; # the default SMTP PORT
        var $CRLF = "\r\n";  # CRLF pair

        var $smtp_conn;      # the socket to the server
        var $error;          # error if any on the last call
        var $helo_rply;      # the reply the server sent to us for HELO

        var $do_debug;       # the level of debug to perform

        /*
         * SMTP()
         *
         * Initialize the class so that the data is in a known state.
         */
        function SMTP() {
            $this->smtp_conn = 0;
            $this->error = null;
            $this->helo_rply = null;

            $this->do_debug = 0;
        }

        /************************************************************
         *                    CONNECTION FUNCTIONS                  *
         ***********************************************************/

        /*
         * Connect($host, $port=0, $tval=30)
         *
         * Connect to the server specified on the port specified.
         * If the port is not specified use the default SMTP_PORT.
         * If tval is specified then a connection will try and be
         * established with the server for that number of seconds.
         * If tval is not specified the default is 30 seconds to
         * try on the connection.
         *
         * SMTP CODE SUCCESS: 220
         * SMTP CODE FAILURE: 421
         */
        function Connect($host,$port=0,$tval=30) {
            # set the error val to null so there is no confusion
            $this->error = null;

            # make sure we are __not__ connected
            if($this->connected()) {
                # ok we are connected! what should we do?
                # for now we will just give an error saying we
                # are already connected
                $this->error =
                    array("error" => "Already connected to a server");
                return false;
            }

            if(empty($port)) {
                $port = $this->SMTP_PORT;
            }

            #connect to the smtp server
            $this->smtp_conn = fsockopen($host,    # the host of the server
                                         $port,    # the port to use
                                         $errno,   # error number if any
                                         $errstr,  # error message if any
                                         $tval);   # give up after ? secs
            # verify we connected properly
            if(empty($this->smtp_conn)) {
                $this->error = array("error" => "Failed to connect to server",
                                     "errno" => $errno,
                                     "errstr" => $errstr);
                if($this->do_debug >= 1) {
                    echo "SMTP -> ERROR: " . $this->error["error"] .
                             ": $errstr ($errno)" . $this->CRLF;
                }
                return false;
            }

            # sometimes the SMTP server takes a little longer to respond
            # so we will give it a longer timeout for the first read
            // Windows still does not have support for this timeout function
            if(substr(PHP_OS, 0, 3) != "WIN")
               socket_set_timeout($this->smtp_conn, 1, 0);

            # get any announcement stuff
            $announce = $this->get_lines();

            # set the timeout  of any socket functions at 1/10 of a second
            //if(function_exists("socket_set_timeout"))
            //   socket_set_timeout($this->smtp_conn, 0, 100000);

            if($this->do_debug >= 2) {
                echo "SMTP -> FROM SERVER:" . $this->CRLF . $announce;
            }

            return true;
        }

        /*
         * Authenticate()
         *
         * Performs SMTP authentication.  Must be run after running the
         * Hello() method.  Returns true if successfully authenticated.
         */
        function Authenticate($username, $password) {
            // Start authentication
            fputs($this->smtp_conn,"AUTH LOGIN" . $this->CRLF);

            $rply = $this->get_lines();
            $code = substr($rply,0,3);

            if($code != 334) {
                $this->error =
                    array("error" => "AUTH not accepted from server",
                          "smtp_code" => $code,
                          "smtp_msg" => substr($rply,4));
                if($this->do_debug >= 1) {
                    echo "SMTP -> ERROR: " . $this->error["error"] .
                             ": " . $rply . $this->CRLF;
                }
                return false;
            }

            // Send encoded username
            fputs($this->smtp_conn, base64_encode($username) . $this->CRLF);

            $rply = $this->get_lines();
            $code = substr($rply,0,3);

            if($code != 334) {
                $this->error =
                    array("error" => "Username not accepted from server",
                          "smtp_code" => $code,
                          "smtp_msg" => substr($rply,4));
                if($this->do_debug >= 1) {
                    echo "SMTP -> ERROR: " . $this->error["error"] .
                             ": " . $rply . $this->CRLF;
                }
                return false;
            }

            // Send encoded password
            fputs($this->smtp_conn, base64_encode($password) . $this->CRLF);

            $rply = $this->get_lines();
            $code = substr($rply,0,3);

            if($code != 235) {
                $this->error =
                    array("error" => "Password not accepted from server",
                          "smtp_code" => $code,
                          "smtp_msg" => substr($rply,4));
                if($this->do_debug >= 1) {
                    echo "SMTP -> ERROR: " . $this->error["error"] .
                             ": " . $rply . $this->CRLF;
                }
                return false;
            }

            return true;
        }

        /*
         * Connected()
         *
         * Returns true if connected to a server otherwise false
         */
        function Connected() {
            if(!empty($this->smtp_conn)) {
                $sock_status = socket_get_status($this->smtp_conn);
                if($sock_status["eof"]) {
                    # hmm this is an odd situation... the socket is
                    # valid but we aren't connected anymore
                    if($this->do_debug >= 1) {
                        echo "SMTP -> NOTICE:" . $this->CRLF .
                             "EOF caught while checking if connected";
                    }
                    $this->Close();
                    return false;
                }
                return true; # everything looks good
            }
            return false;
        }

        /*
         * Close()
         *
         * Closes the socket and cleans up the state of the class.
         * It is not considered good to use this function without
         * first trying to use QUIT.
         */
        function Close() {
            $this->error = null; # so there is no confusion
            $this->helo_rply = null;
            if(!empty($this->smtp_conn)) {
                # close the connection and cleanup
                fclose($this->smtp_conn);
                $this->smtp_conn = 0;
            }
        }


        /**************************************************************
         *                        SMTP COMMANDS                       *
         *************************************************************/

        /*
         * Data($msg_data)
         *
         * Issues a data command and sends the msg_data to the server
         * finializing the mail transaction. $msg_data is the message
         * that is to be send with the headers. Each header needs to be
         * on a single line followed by a <CRLF> with the message headers
         * and the message body being seperated by and additional <CRLF>.
         *
         * Implements rfc 821: DATA <CRLF>
         *
         * SMTP CODE INTERMEDIATE: 354
         *     [data]
         *     <CRLF>.<CRLF>
         *     SMTP CODE SUCCESS: 250
         *     SMTP CODE FAILURE: 552,554,451,452
         * SMTP CODE FAILURE: 451,554
         * SMTP CODE ERROR  : 500,501,503,421
         */
        function Data($msg_data) {
            $this->error = null; # so no confusion is caused

            if(!$this->connected()) {
                $this->error = array(
                        "error" => "Called Data() without being connected");
                return false;
            }

            fputs($this->smtp_conn,"DATA" . $this->CRLF);

            $rply = $this->get_lines();
            $code = substr($rply,0,3);

            if($this->do_debug >= 2) {
                echo "SMTP -> FROM SERVER:" . $this->CRLF . $rply;
            }

            if($code != 354) {
                $this->error =
                    array("error" => "DATA command not accepted from server",
                          "smtp_code" => $code,
                          "smtp_msg" => substr($rply,4));
                if($this->do_debug >= 1) {
                    echo "SMTP -> ERROR: " . $this->error["error"] .
                             ": " . $rply . $this->CRLF;
                }
                return false;
            }

            # the server is ready to accept data!
            # according to rfc 821 we should not send more than 1000
            # including the CRLF
            # characters on a single line so we will break the data up
            # into lines by \r and/or \n then if needed we will break
            # each of those into smaller lines to fit within the limit.
            # in addition we will be looking for lines that start with
            # a period '.' and append and additional period '.' to that
            # line. NOTE: this does not count towards are limit.

            # normalize the line breaks so we know the explode works
            $msg_data = str_replace("\r\n","\n",$msg_data);
            $msg_data = str_replace("\r","\n",$msg_data);
            $lines = explode("\n",$msg_data);

            # we need to find a good way to determine is headers are
            # in the msg_data or if it is a straight msg body
            # currently I'm assuming rfc 822 definitions of msg headers
            # and if the first field of the first line (':' sperated)
            # does not contain a space then it _should_ be a header
            # and we can process all lines before a blank "" line as
            # headers.
            $field = substr($lines[0],0,strpos($lines[0],":"));
            $in_headers = false;
            if(!empty($field) && !strstr($field," ")) {
                $in_headers = true;
            }

            $max_line_length = 998; # used below; set here for ease in change

            while(list(,$line) = @each($lines)) {
                $lines_out = null;
                if($line == "" && $in_headers) {
                    $in_headers = false;
                }
                # ok we need to break this line up into several
                # smaller lines
                while(strlen($line) > $max_line_length) {
                    $pos = strrpos(substr($line,0,$max_line_length)," ");
                    $lines_out[] = substr($line,0,$pos);
                    $line = substr($line,$pos + 1);
                    # if we are processing headers we need to
                    # add a LWSP-char to the front of the new line
                    # rfc 822 on long msg headers
                    if($in_headers) {
                        $line = "\t" . $line;
                    }
                }
                $lines_out[] = $line;

                # now send the lines to the server
                while(list(,$line_out) = @each($lines_out)) {
                    if(strlen($line_out) > 0)
                    {
                        if(substr($line_out, 0, 1) == ".") {
                            $line_out = "." . $line_out;
                        }
                    }
                    fputs($this->smtp_conn,$line_out . $this->CRLF);
                }
            }

            # ok all the message data has been sent so lets get this
            # over with aleady
            
            
            #@FIXED xiaoma 2013.3.7 17:33  如果邮件服务器没能及时反馈状态 ，则进行重新请求(每秒请求一次)，直至返回信息，最多请求5次
            $rply_num = 0 ;
            fputs($this->smtp_conn, $this->CRLF . "." . $this->CRLF);
            do 
            {
                $rply = $this->get_lines();
                sleep(1);
                $rply_num++ ;
            }while ($rply == ''  && $rply_num < 5  );
            
            $code = substr($rply,0,3);

            if($this->do_debug >= 2) {
                echo "SMTP -> FROM SERVER:" . $this->CRLF . $rply;
            }
            
            if($code != 250) {
                $this->error =
                    array("error" => "DATA not accepted from server",
                          "smtp_code" => $code,
                          "smtp_msg" => substr($rply,4));
                if($this->do_debug >= 1) {
                    echo "SMTP -> ERROR: " . $this->error["error"] .
                             ": " . $rply . $this->CRLF;
                }
                return false;
            }
            return true;
        }

        /*
         * Expand($name)
         *
         * Expand takes the name and asks the server to list all the
         * people who are members of the _list_. Expand will return
         * back and array of the result or false if an error occurs.
         * Each value in the array returned has the format of:
         *     [ <full-name> <sp> ] <path>
         * The definition of <path> is defined in rfc 821
         *
         * Implements rfc 821: EXPN <SP> <string> <CRLF>
         *
         * SMTP CODE SUCCESS: 250
         * SMTP CODE FAILURE: 550
         * SMTP CODE ERROR  : 500,501,502,504,421
         */
        function Expand($name) {
            $this->error = null; # so no confusion is caused

            if(!$this->connected()) {
                $this->error = array(
                        "error" => "Called Expand() without being connected");
                return false;
            }

            fputs($this->smtp_conn,"EXPN " . $name . $this->CRLF);

            $rply = $this->get_lines();
            $code = substr($rply,0,3);

            if($this->do_debug >= 2) {
                echo "SMTP -> FROM SERVER:" . $this->CRLF . $rply;
            }

            if($code != 250) {
                $this->error =
                    array("error" => "EXPN not accepted from server",
                          "smtp_code" => $code,
                          "smtp_msg" => substr($rply,4));
                if($this->do_debug >= 1) {
                    echo "SMTP -> ERROR: " . $this->error["error"] .
                             ": " . $rply . $this->CRLF;
                }
                return false;
            }

            # parse the reply and place in our array to return to user
            $entries = explode($this->CRLF,$rply);
            while(list(,$l) = @each($entries)) {
                $list[] = substr($l,4);
            }

            return $rval;
        }

        /*
         * Hello($host="")
         *
         * Sends the HELO command to the smtp server.
         * This makes sure that we and the server are in
         * the same known state.
         *
         * Implements from rfc 821: HELO <SP> <domain> <CRLF>
         *
         * SMTP CODE SUCCESS: 250
         * SMTP CODE ERROR  : 500, 501, 504, 421
         */
        function Hello($host="") {
            $this->error = null; # so no confusion is caused

            if(!$this->connected()) {
                $this->error = array(
                        "error" => "Called Hello() without being connected");
                return false;
            }

            # if a hostname for the HELO wasn't specified determine
            # a suitable one to send
            if(empty($host)) {
                # we need to determine some sort of appopiate default
                # to send to the server
                $host = "localhost";
            }

            fputs($this->smtp_conn,"HELO " . $host . $this->CRLF);

            $rply = $this->get_lines();
            $code = substr($rply,0,3);

            if($this->do_debug >= 2) {
                echo "SMTP -> FROM SERVER: " . $this->CRLF . $rply;
            }

            if($code != 250) {
                $this->error =
                    array("error" => "HELO not accepted from server",
                          "smtp_code" => $code,
                          "smtp_msg" => substr($rply,4));
                if($this->do_debug >= 1) {
                    echo "SMTP -> ERROR: " . $this->error["error"] .
                             ": " . $rply . $this->CRLF;
                }
                return false;
            }

            $this->helo_rply = $rply;

            return true;
        }

        /*
         * Help($keyword="")
         *
         * Gets help information on the keyword specified. If the keyword
         * is not specified then returns generic help, ussually contianing
         * A list of keywords that help is available on. This function
         * returns the results back to the user. It is up to the user to
         * handle the returned data. If an error occurs then false is
         * returned with $this->error set appropiately.
         *
         * Implements rfc 821: HELP [ <SP> <string> ] <CRLF>
         *
         * SMTP CODE SUCCESS: 211,214
         * SMTP CODE ERROR  : 500,501,502,504,421
         *
         */
        function Help($keyword="") {
            $this->error = null; # to avoid confusion

            if(!$this->connected()) {
                $this->error = array(
                        "error" => "Called Help() without being connected");
                return false;
            }

            $extra = "";
            if(!empty($keyword)) {
                $extra = " " . $keyword;
            }

            fputs($this->smtp_conn,"HELP" . $extra . $this->CRLF);

            $rply = $this->get_lines();
            $code = substr($rply,0,3);

            if($this->do_debug >= 2) {
                echo "SMTP -> FROM SERVER:" . $this->CRLF . $rply;
            }

            if($code != 211 && $code != 214) {
                $this->error =
                    array("error" => "HELP not accepted from server",
                          "smtp_code" => $code,
                          "smtp_msg" => substr($rply,4));
                if($this->do_debug >= 1) {
                    echo "SMTP -> ERROR: " . $this->error["error"] .
                             ": " . $rply . $this->CRLF;
                }
                return false;
            }

            return $rply;
        }

        /*
         * Mail($from)
         *
         * Starts a mail transaction from the email address specified in
         * $from. Returns true if successful or false otherwise. If True
         * the mail transaction is started and then one or more Recipient
         * commands may be called followed by a Data command.
         *
         * Implements rfc 821: MAIL <SP> FROM:<reverse-path> <CRLF>
         *
         * SMTP CODE SUCCESS: 250
         * SMTP CODE SUCCESS: 552,451,452
         * SMTP CODE SUCCESS: 500,501,421
         */
        function Mail($from) {
            $this->error = null; # so no confusion is caused

            if(!$this->connected()) {
                $this->error = array(
                        "error" => "Called Mail() without being connected");
                return false;
            }

            fputs($this->smtp_conn,"MAIL FROM:" . $from . $this->CRLF);

            $rply = $this->get_lines();
            $code = substr($rply,0,3);

            if($this->do_debug >= 2) {
                echo "SMTP -> FROM SERVER:" . $this->CRLF . $rply;
            }

            if($code != 250) {
                $this->error =
                    array("error" => "MAIL not accepted from server",
                          "smtp_code" => $code,
                          "smtp_msg" => substr($rply,4));
                if($this->do_debug >= 1) {
                    echo "SMTP -> ERROR: " . $this->error["error"] .
                             ": " . $rply . $this->CRLF;
                }
                return false;
            }
            return true;
        }

        /*
         * Noop()
         *
         * Sends the command NOOP to the SMTP server.
         *
         * Implements from rfc 821: NOOP <CRLF>
         *
         * SMTP CODE SUCCESS: 250
         * SMTP CODE ERROR  : 500, 421
         */
        function Noop() {
            $this->error = null; # so no confusion is caused

            if(!$this->connected()) {
                $this->error = array(
                        "error" => "Called Noop() without being connected");
                return false;
            }

            fputs($this->smtp_conn,"NOOP" . $this->CRLF);

            $rply = $this->get_lines();
            $code = substr($rply,0,3);

            if($this->do_debug >= 2) {
                echo "SMTP -> FROM SERVER:" . $this->CRLF . $rply;
            }

            if($code != 250) {
                $this->error =
                    array("error" => "NOOP not accepted from server",
                          "smtp_code" => $code,
                          "smtp_msg" => substr($rply,4));
                if($this->do_debug >= 1) {
                    echo "SMTP -> ERROR: " . $this->error["error"] .
                             ": " . $rply . $this->CRLF;
                }
                return false;
            }
            return true;
        }

        /*
         * Quit($close_on_error=true)
         *
         * Sends the quit command to the server and then closes the socket
         * if there is no error or the $close_on_error argument is true.
         *
         * Implements from rfc 821: QUIT <CRLF>
         *
         * SMTP CODE SUCCESS: 221
         * SMTP CODE ERROR  : 500
         */
        function Quit($close_on_error=true) {
            $this->error = null; # so there is no confusion

            if(!$this->connected()) {
                $this->error = array(
                        "error" => "Called Quit() without being connected");
                return false;
            }

            # send the quit command to the server
            fputs($this->smtp_conn,"quit" . $this->CRLF);

            # get any good-bye messages
            $byemsg = $this->get_lines();

            if($this->do_debug >= 2) {
                echo "SMTP -> FROM SERVER:" . $this->CRLF . $byemsg;
            }

            $rval = true;
            $e = null;

            $code = substr($byemsg,0,3);
            if($code != 221) {
                # use e as a tmp var cause Close will overwrite $this->error
                $e = array("error" => "SMTP server rejected quit command",
                           "smtp_code" => $code,
                           "smtp_rply" => substr($byemsg,4));
                $rval = false;
                if($this->do_debug >= 1) {
                    echo "SMTP -> ERROR: " . $e["error"] . ": " .
                             $byemsg . $this->CRLF;
                }
            }

            if(empty($e) || $close_on_error) {
                $this->Close();
            }

            return $rval;
        }

        /*
         * Recipient($to)
         *
         * Sends the command RCPT to the SMTP server with the TO: argument of $to.
         * Returns true if the recipient was accepted false if it was rejected.
         *
         * Implements from rfc 821: RCPT <SP> TO:<forward-path> <CRLF>
         *
         * SMTP CODE SUCCESS: 250,251
         * SMTP CODE FAILURE: 550,551,552,553,450,451,452
         * SMTP CODE ERROR  : 500,501,503,421
         */
        function Recipient($to) {
            $this->error = null; # so no confusion is caused

            if(!$this->connected()) {
                $this->error = array(
                        "error" => "Called Recipient() without being connected");
                return false;
            }

            fputs($this->smtp_conn,"RCPT TO:" . $to . $this->CRLF);

            $rply = $this->get_lines();
            $code = substr($rply,0,3);

            if($this->do_debug >= 2) {
                echo "SMTP -> FROM SERVER:" . $this->CRLF . $rply;
            }

            if($code != 250 && $code != 251) {
                $this->error =
                    array("error" => "RCPT not accepted from server",
                          "smtp_code" => $code,
                          "smtp_msg" => substr($rply,4));
                if($this->do_debug >= 1) {
                    echo "SMTP -> ERROR: " . $this->error["error"] .
                             ": " . $rply . $this->CRLF;
                }
                return false;
            }
            return true;
        }

        /*
         * Reset()
         *
         * Sends the RSET command to abort and transaction that is
         * currently in progress. Returns true if successful false
         * otherwise.
         *
         * Implements rfc 821: RSET <CRLF>
         *
         * SMTP CODE SUCCESS: 250
         * SMTP CODE ERROR  : 500,501,504,421
         */
        function Reset() {
            $this->error = null; # so no confusion is caused

            if(!$this->connected()) {
                $this->error = array(
                        "error" => "Called Reset() without being connected");
                return false;
            }

            fputs($this->smtp_conn,"RSET" . $this->CRLF);

            $rply = $this->get_lines();
            $code = substr($rply,0,3);

            if($this->do_debug >= 2) {
                echo "SMTP -> FROM SERVER:" . $this->CRLF . $rply;
            }

            if($code != 250) {
                $this->error =
                    array("error" => "RSET failed",
                          "smtp_code" => $code,
                          "smtp_msg" => substr($rply,4));
                if($this->do_debug >= 1) {
                    echo "SMTP -> ERROR: " . $this->error["error"] .
                             ": " . $rply . $this->CRLF;
                }
                return false;
            }

            return true;
        }

        /*
         * Send($from)
         *
         * Starts a mail transaction from the email address specified in
         * $from. Returns true if successful or false otherwise. If True
         * the mail transaction is started and then one or more Recipient
         * commands may be called followed by a Data command. This command
         * will send the message to the users terminal if they are logged
         * in.
         *
         * Implements rfc 821: SEND <SP> FROM:<reverse-path> <CRLF>
         *
         * SMTP CODE SUCCESS: 250
         * SMTP CODE SUCCESS: 552,451,452
         * SMTP CODE SUCCESS: 500,501,502,421
         */
        function Send($from) {
            $this->error = null; # so no confusion is caused

            if(!$this->connected()) {
                $this->error = array(
                        "error" => "Called Send() without being connected");
                return false;
            }

            fputs($this->smtp_conn,"SEND FROM:" . $from . $this->CRLF);

            $rply = $this->get_lines();
            $code = substr($rply,0,3);

            if($this->do_debug >= 2) {
                echo "SMTP -> FROM SERVER:" . $this->CRLF . $rply;
            }

            if($code != 250) {
                $this->error =
                    array("error" => "SEND not accepted from server",
                          "smtp_code" => $code,
                          "smtp_msg" => substr($rply,4));
                if($this->do_debug >= 1) {
                    echo "SMTP -> ERROR: " . $this->error["error"] .
                             ": " . $rply . $this->CRLF;
                }
                return false;
            }
            return true;
        }

        /*
         * SendAndMail($from)
         *
         * Starts a mail transaction from the email address specified in
         * $from. Returns true if successful or false otherwise. If True
         * the mail transaction is started and then one or more Recipient
         * commands may be called followed by a Data command. This command
         * will send the message to the users terminal if they are logged
         * in and send them an email.
         *
         * Implements rfc 821: SAML <SP> FROM:<reverse-path> <CRLF>
         *
         * SMTP CODE SUCCESS: 250
         * SMTP CODE SUCCESS: 552,451,452
         * SMTP CODE SUCCESS: 500,501,502,421
         */
        function SendAndMail($from) {
            $this->error = null; # so no confusion is caused

            if(!$this->connected()) {
                $this->error = array(
                    "error" => "Called SendAndMail() without being connected");
                return false;
            }

            fputs($this->smtp_conn,"SAML FROM:" . $from . $this->CRLF);

            $rply = $this->get_lines();
            $code = substr($rply,0,3);

            if($this->do_debug >= 2) {
                echo "SMTP -> FROM SERVER:" . $this->CRLF . $rply;
            }

            if($code != 250) {
                $this->error =
                    array("error" => "SAML not accepted from server",
                          "smtp_code" => $code,
                          "smtp_msg" => substr($rply,4));
                if($this->do_debug >= 1) {
                    echo "SMTP -> ERROR: " . $this->error["error"] .
                             ": " . $rply . $this->CRLF;
                }
                return false;
            }
            return true;
        }

        /*
         * SendOrMail($from)
         *
         * Starts a mail transaction from the email address specified in
         * $from. Returns true if successful or false otherwise. If True
         * the mail transaction is started and then one or more Recipient
         * commands may be called followed by a Data command. This command
         * will send the message to the users terminal if they are logged
         * in or mail it to them if they are not.
         *
         * Implements rfc 821: SOML <SP> FROM:<reverse-path> <CRLF>
         *
         * SMTP CODE SUCCESS: 250
         * SMTP CODE SUCCESS: 552,451,452
         * SMTP CODE SUCCESS: 500,501,502,421
         */
        function SendOrMail($from) {
            $this->error = null; # so no confusion is caused

            if(!$this->connected()) {
                $this->error = array(
                    "error" => "Called SendOrMail() without being connected");
                return false;
            }

            fputs($this->smtp_conn,"SOML FROM:" . $from . $this->CRLF);

            $rply = $this->get_lines();
            $code = substr($rply,0,3);

            if($this->do_debug >= 2) {
                echo "SMTP -> FROM SERVER:" . $this->CRLF . $rply;
            }

            if($code != 250) {
                $this->error =
                    array("error" => "SOML not accepted from server",
                          "smtp_code" => $code,
                          "smtp_msg" => substr($rply,4));
                if($this->do_debug >= 1) {
                    echo "SMTP -> ERROR: " . $this->error["error"] .
                             ": " . $rply . $this->CRLF;
                }
                return false;
            }
            return true;
        }

        /*
         * Turn()
         *
         * This is an optional command for SMTP that this class does not
         * support. This method is here to make the RFC821 Definition
         * complete for this class and __may__ be implimented in the future
         *
         * Implements from rfc 821: TURN <CRLF>
         *
         * SMTP CODE SUCCESS: 250
         * SMTP CODE FAILURE: 502
         * SMTP CODE ERROR  : 500, 503
         */
        function Turn() {
            $this->error = array("error" => "This method, TURN, of the SMTP ".
                                            "is not implemented");
            if($this->do_debug >= 1) {
                echo "SMTP -> NOTICE: " . $this->error["error"] . $this->CRLF;
            }
            return false;
        }

        /*
         * Verify($name)
         *
         * Verifies that the name is recognized by the server.
         * Returns false if the name could not be verified otherwise
         * the response from the server is returned.
         *
         * Implements rfc 821: VRFY <SP> <string> <CRLF>
         *
         * SMTP CODE SUCCESS: 250,251
         * SMTP CODE FAILURE: 550,551,553
         * SMTP CODE ERROR  : 500,501,502,421
         */
        function Verify($name) {
            $this->error = null; # so no confusion is caused

            if(!$this->connected()) {
                $this->error = array(
                        "error" => "Called Verify() without being connected");
                return false;
            }

            fputs($this->smtp_conn,"VRFY " . $name . $this->CRLF);

            $rply = $this->get_lines();
            $code = substr($rply,0,3);

            if($this->do_debug >= 2) {
                echo "SMTP -> FROM SERVER:" . $this->CRLF . $rply;
            }

            if($code != 250 && $code != 251) {
                $this->error =
                    array("error" => "VRFY failed on name '$name'",
                          "smtp_code" => $code,
                          "smtp_msg" => substr($rply,4));
                if($this->do_debug >= 1) {
                    echo "SMTP -> ERROR: " . $this->error["error"] .
                             ": " . $rply . $this->CRLF;
                }
                return false;
            }
            return $rply;
        }

        /******************************************************************
         *                       INTERNAL FUNCTIONS                       *
         ******************************************************************/

        /*
         * get_lines()
         *
         * __internal_use_only__: read in as many lines as possible
         * either before eof or socket timeout occurs on the operation.
         * With SMTP we can tell if we have more lines to read if the
         * 4th character is '-' symbol. If it is a space then we don't
         * need to read anything else.
         */
        function get_lines() {
            $data = "";
            while($str = fgets($this->smtp_conn,515)) {
                if($this->do_debug >= 4) {
                    echo "SMTP -> get_lines(): \$data was \"$data\"" .
                             $this->CRLF;
                    echo "SMTP -> get_lines(): \$str is \"$str\"" .
                             $this->CRLF;
                }
                $data .= $str;
                if($this->do_debug >= 4) {
                    echo "SMTP -> get_lines(): \$data is \"$data\"" . $this->CRLF;
                }
                # if the 4th character is a space then we are done reading
                # so just break the loop
                if(substr($str,3,1) == " ") { break; }
            }
            return $data;
        }

    }


 ?>