source: trunk/lib/Utilities.inc.php @ 340

<?php
/**
 * Utilities.inc.php
 * Code by Strangecode :: www.strangecode.com :: This document contains copyrighted information
 */


/**
 * Print variable dump.
 *
 * @param  mixed $var      Variable to dump.
 * @param  bool  $display   Hide the dump in HTML comments?
 * @param  bool  $var_dump Use var_dump instead of print_r.
 */
function dump($var, $display=false, $var_dump=false)
{
    echo $display ? "\n<br /><pre>\n" : "\n\n\n<!--\n";
    if ($var_dump) {
        var_dump($var);
    } else {
        print_r($var);
    }
    echo $display ?  "\n</pre><br />\n" : "\n-->\n\n\n";
}

/**
 * Return dump as variable.
 *
 * @param  mixed $var           Variable to dump.
 * @param  bool  $serialize     Remove line-endings. Useful for logging variables.
 * @return string Dump of var.
 */
function getDump($var, $serialize=false)
{
    ob_start();
    print_r($var);
    $d = ob_get_contents();
    ob_end_clean();
    return $serialize ? preg_replace('/\s+/m', '', $d) : $d;
}

/**
 * Return dump as cleaned text. Useful for dumping data into emails.
 *
 * @param  array    $var        Variable to dump.
 * @param  strong   $indent     A string to prepend indented lines (tab for example).
 * @return string Dump of var.
 */
function fancyDump($var, $indent='')
{
    $output = '';
    if (is_array($var)) {
        foreach ($var as $k=>$v) {
            $k = ucfirst(mb_strtolower(str_replace(array('_', '  '), ' ', $k)));
            if (is_array($v)) {
                $output .= sprintf("\n%s%s: %s\n", $indent, $k, fancyDump($v, $indent . $indent));
            } else {
                $output .= sprintf("%s%s: %s\n", $indent, $k, $v);
            }
        }
    } else {
        $output .= sprintf("%s%s\n", $indent, $var);
    }
    return $output;
}

/**
 * Returns text with appropriate html translations.
 *
 * @param  string $text             Text to clean.
 * @param  bool   $preserve_html    If set to true, oTxt will not translate <, >, ", or '
 *                                  characters into HTML entities. This allows HTML to pass through unmunged.
 * @return string                   Cleaned text.
 */
function oTxt($text, $preserve_html=false)
{
    $app =& App::getInstance();

    $search = array();
    $replace = array();

    // Make converted ampersand entities into normal ampersands (they will be done manually later) to retain HTML entities.
    $search['retain_ampersand']     = '/&amp;/';
    $replace['retain_ampersand']    = '&';

    if ($preserve_html) {
        // Convert characters that must remain non-entities for displaying HTML.
        $search['retain_left_angle']       = '/&lt;/';
        $replace['retain_left_angle']      = '<';

        $search['retain_right_angle']      = '/&gt;/';
        $replace['retain_right_angle']     = '>';

        $search['retain_single_quote']     = '/&#039;/';
        $replace['retain_single_quote']    = "'";

        $search['retain_double_quote']     = '/&quot;/';
        $replace['retain_double_quote']    = '"';
    }

    // & becomes &amp;. Exclude any occurrence where the & is followed by a alphanum or unicode character.
    $search['ampersand']        = '/&(?![\w\d#]{1,10};)/';
    $replace['ampersand']       = '&amp;';

    return preg_replace($search, $replace, htmlspecialchars($text, ENT_QUOTES, $app->getParam('character_set')));
}

/**
 * Returns text with stylistic modifications. Warning: this will break some HTML attributes!
 * TODO: Allow a string such as this to be passed: <a href="javascript:openPopup('/foo/bar.php')">Click here</a>
 *
 * @param  string   $text Text to clean.
 * @return string         Cleaned text.
 */
function fancyTxt($text)
{
    $search = array();
    $replace = array();

    // "double quoted text"  becomes  &ldquo;double quoted text&rdquo;
    $search['double_quotes']    = '/(^|[^\w=])(?:"|&quot;|&#34;|&#x22;|&ldquo;)([^"]+?)(?:"|&quot;|&#34;|&#x22;|&rdquo;)([^\w]|$)/ms'; // " is the same as &quot; and &#34; and &#x22;
    $replace['double_quotes']   = '$1&ldquo;$2&rdquo;$3';

    // text's apostrophes  become  text&rsquo;s apostrophes
    $search['apostrophe']       = '/(\w)(?:\'|&#39;|&#039;)(\w)/ms';
    $replace['apostrophe']      = '$1&rsquo;$2';

    // 'single quoted text'  becomes  &lsquo;single quoted text&rsquo;
    $search['single_quotes']    = '/(^|[^\w=])(?:\'|&#39;|&lsquo;)([^\']+?)(?:\'|&#39;|&rsquo;)([^\w]|$)/ms';
    $replace['single_quotes']   = '$1&lsquo;$2&rsquo;$3';

    // plural posessives' apostrophes become posessives&rsquo;
    $search['apostrophes']      = '/(s)(?:\'|&#39;|&#039;)(\s)/ms';
    $replace['apostrophes']     = '$1&rsquo;$2';

    // em--dashes  become em&mdash;dashes
    $search['em_dash']          = '/(\s*[^!<-])--([^>-]\s*)/';
    $replace['em_dash']         = '$1&mdash;$2';

    return preg_replace($search, $replace, $text);
}

/**
 * Applies a class to search terms to highlight them ala google results.
 *
 * @param  string   $text   Input text to search.
 * @param  string   $search String of word(s) that will be highlighted.
 * @param  string   $class  CSS class to apply.
 * @return string           Text with searched words wrapped in <span>.
 */
function highlightWords($text, $search, $class='sc-highlightwords')
{
    $words = preg_split('/[^\w]/', $search, -1, PREG_SPLIT_NO_EMPTY);
    
    $search = array();
    $replace = array();
    
    foreach ($words as $w) {
        if ('' != trim($w)) {
            $search[] = '/\b(' . preg_quote($w) . ')\b/i';
            $replace[] = '<span class="' . $class . '">$1</span>';
        }
    }

    return empty($replace) ? $text : preg_replace($search, $replace, $text);
}


/**
 * Generates a hexadecimal html color based on provided word.
 *
 * @access public
 * @param  string $text  A string for which to convert to color.
 * @return string  A hexadecimal html color.
 */
function getTextColor($text, $method=1)
{
    $hash = md5($text);
    $rgb = array(
        mb_substr($hash, 0, 1),
        mb_substr($hash, 1, 1),
        mb_substr($hash, 2, 1),
        mb_substr($hash, 3, 1),
        mb_substr($hash, 4, 1),
        mb_substr($hash, 5, 1),
    );

    switch ($method) {
    case 1 :
    default :
        // Reduce all hex values slightly to avoid all white.
        array_walk($rgb, create_function('&$v', '$v = dechex(round(hexdec($v) * 0.87));'));
        break;
    case 2 :
        foreach ($rgb as $i => $v) {
            if (hexdec($v) > hexdec('c')) {
                $rgb[$i] = dechex(hexdec('f') - hexdec($v));
            }
        }
        break;
    }

    return join('', $rgb);
}

/**
 * Encodes a string into unicode values 128-255.
 * Useful for hiding an email address from spambots.
 *
 * @access  public
 * @param   string   $text   A line of text to encode.
 * @return  string   Encoded text.
 */
function encodeAscii($text)
{
    $output = '';
    $num = mb_strlen($text);
    for ($i=0; $i<$num; $i++) {
        $output .= sprintf('&#%03s', ord($text{$i}));
    }
    return $output;
}

/**
 * Encodes an email into a "user at domain dot com" format.
 *
 * @access  public
 * @param   string   $email   An email to encode.
 * @param   string   $at      Replaces the @.
 * @param   string   $dot     Replaces the ..
 * @return  string   Encoded email.
 */
function encodeEmail($email, $at=' at ', $dot=' dot ')
{
    $search = array('/@/', '/\./');
    $replace = array($at, $dot);
    return preg_replace($search, $replace, $email);
}

/**
 * Turns "a really long string" into "a rea...string"
 *
 * @access  public
 * @param   string  $str    Input string
 * @param   int     $len    Maximum string length.
 * @param   string  $where  Where to cut the string. One of: 'start', 'middle', or 'end'.
 * @return  string          Truncated output string
 * @author  Quinn Comendant <quinn@strangecode.com>
 * @since   29 Mar 2006 13:48:49
 */
function truncate($str, $len, $where='middle', $delim='&hellip;')
{
    if ($len <= 3 || mb_strlen($str) <= 3) {
        return '';
    }
    $part1 = floor(($len - 3) / 2);
    $part2 = ceil(($len - 3) / 2);
    switch ($where) {
    case 'start' :
        return preg_replace(array(sprintf('/^.{4,}(.{%s})$/sU', $part1 + $part2), '/\s*\.{3,}\s*/sU'), array($delim . '$1', $delim), $str);
        break;
    default :
    case 'middle' :
        return preg_replace(array(sprintf('/^(.{%s}).{4,}(.{%s})$/sU', $part1, $part2), '/\s*\.{3,}\s*/sU'), array('$1' . $delim . '$2', $delim), $str);
        break;    
    case 'end' :
        return preg_replace(array(sprintf('/^(.{%s}).{4,}$/sU', $part1 + $part2), '/\s*\.{3,}\s*/sU'), array('$1' . $delim, $delim), $str);
        break;
    }
}

/*
* A substitution for the missing mb_ucfirst function.
*
* @access   public
* @param    string  $strong The string
* @return   string          String with uper-cased first character.
* @author   Quinn Comendant <quinn@strangecode.com>
* @version  1.0
* @since    06 Dec 2008 17:04:01
*/
if (!function_exists('mb_ucfirst')) {    
    function mb_ucfirst($string)
    {
        return mb_strtoupper(mb_substr($string, 0, 1)) . mb_substr($string, 1, mb_strlen($string));
    }
}

/**
 * Return a human readable disk space measurement. Input value measured in bytes.
 *
 * @param       int    $size        Size in bytes.
 * @param       int    $unit        The maximum unit
 * @param       int    $format      The return string format
 * @author      Aidan Lister <aidan@php.net>
 * @version     1.1.0
 */
function humanFileSize($size, $format='%01.2f %s', $max_unit=null, $multiplier=1024)
{
    // Units
    $units = array('B', 'KB', 'MB', 'GB', 'TB');
    $ii = count($units) - 1;

    // Max unit
    $max_unit = array_search((string) $max_unit, $units);
    if ($max_unit === null || $max_unit === false) {
        $max_unit = $ii;
    }

    // Loop
    $i = 0;
    while ($max_unit != $i && $size >= $multiplier && $i < $ii) {
        $size /= $multiplier;
        $i++;
    }

    return sprintf($format, $size, $units[$i]);
}

/*
* Returns a human readable amount of time for the given amount of seconds.
* 
* 45 seconds
* 12 minutes
* 3.5 hours
* 2 days
* 1 week
* 4 months
* 
* Months are calculated using the real number of days in a year: 365.2422 / 12.
*
* @access   public
* @param    int $seconds Seconds of time.
* @param    string $max_unit Key value from the $units array.
* @param    string $format Sprintf formatting string.
* @return   string Value of units elapsed.
* @author   Quinn Comendant <quinn@strangecode.com>
* @version  1.0
* @since    23 Jun 2006 12:15:19
*/
function humanTime($seconds, $max_unit=null, $format='%01.1f')
{
    // Units: array of seconds in the unit, singular and plural unit names.
    $units = array(
        'second' => array(1, _("second"), _("seconds")),
        'minute' => array(60, _("minute"), _("minutes")),
        'hour' => array(3600, _("hour"), _("hours")),
        'day' => array(86400, _("day"), _("days")),
        'week' => array(604800, _("week"), _("weeks")),
        'month' => array(2629743.84, _("month"), _("months")),
        'year' => array(31556926.08, _("year"), _("years")),
        'decade' => array(315569260.8, _("decade"), _("decades")),
    );
    
    // Max unit to calculate.
    $max_unit = isset($units[$max_unit]) ? $max_unit : 'decade';

    $final_time = $seconds;
    $last_unit = 'second';
    foreach ($units as $k => $v) {
        if ($max_unit != $k && $seconds >= $v[0]) {
            $final_time = $seconds / $v[0];
            $last_unit = $k;
        }
    }
    $final_time = sprintf($format, $final_time);
    return sprintf('%s %s', $final_time, (1 == $final_time ? $units[$last_unit][1] : $units[$last_unit][2]));    
}

/**
 * Tests the existence of a file anywhere in the include path.
 *
 * @param   string  $file   File in include path.
 * @return  mixed           False if file not found, the path of the file if it is found.
 * @author  Quinn Comendant <quinn@strangecode.com>
 * @since   03 Dec 2005 14:23:26
 */
function fileExistsIncludePath($file)
{
    $app =& App::getInstance();
    
    foreach (explode(PATH_SEPARATOR, get_include_path()) as $path) {
        $fullpath = $path . DIRECTORY_SEPARATOR . $file;
        if (file_exists($fullpath)) {
            $app->logMsg(sprintf('Found file "%s" at path: %s', $file, $fullpath), LOG_DEBUG, __FILE__, __LINE__);
            return $fullpath;
        } else {
            $app->logMsg(sprintf('File "%s" not found in include_path: %s', $file, get_include_path()), LOG_DEBUG, __FILE__, __LINE__);
            return false;
        }
    }
}

/**
 * Returns stats of a file from the include path.
 *
 * @param   string  $file   File in include path.
 * @param   mixed   $stat   Which statistic to return (or null to return all).
 * @return  mixed           Value of requested key from fstat(), or false on error.
 * @author  Quinn Comendant <quinn@strangecode.com>
 * @since   03 Dec 2005 14:23:26
 */
function statIncludePath($file, $stat=null)
{
    // Open file pointer read-only using include path.
    if ($fp = fopen($file, 'r', true)) {
        // File opened successfully, get stats.
        $stats = fstat($fp);
        fclose($fp);
        // Return specified stats.
        return is_null($stat) ? $stats : $stats[$stat];
    } else {
        return false;
    }
}

/*
* Writes content to the specified file. This function emulates the functionality of file_put_contents from PHP 5.
*
* @access   public
* @param    string  $filename   Path to file.
* @param    string  $content    Data to write into file.
* @return   bool                Success or failure.
* @author   Quinn Comendant <quinn@strangecode.com>
* @since    11 Apr 2006 22:48:30
*/
function filePutContents($filename, $content)
{
    $app =& App::getInstance();

    // Open file for writing and truncate to zero length.
    if ($fp = fopen($filename, 'w')) {
        if (flock($fp, LOCK_EX)) {
            if (!fwrite($fp, $content, mb_strlen($content))) {
                $app->logMsg(sprintf('Failed writing to file: %s', $filename), LOG_ERR, __FILE__, __LINE__);
                fclose($fp);
                return false;
            }
            flock($fp, LOCK_UN);
        } else {
            $app->logMsg(sprintf('Could not lock file for writing: %s', $filename), LOG_ERR, __FILE__, __LINE__);
            fclose($fp);
            return false;
        }
        fclose($fp);
        // Success!
        $app->logMsg(sprintf('Wrote to file: %s', $filename), LOG_DEBUG, __FILE__, __LINE__);
        return true;
    } else {
        $app->logMsg(sprintf('Could not open file for writing: %s', $filename), LOG_ERR, __FILE__, __LINE__);
        return false;
    }
}


/**
 * If $var is net set or null, set it to $default. Otherwise leave it alone.
 * Returns the final value of $var. Use to find a default value of one is not available.
 *
 * @param  mixed $var       The variable that is being set.
 * @param  mixed $default   What to set it to if $val is not currently set.
 * @return mixed            The resulting value of $var.
 */
function setDefault(&$var, $default='')
{
    if (!isset($var)) {
        $var = $default;
    }
    return $var;
}

/**
 * Like preg_quote() except for arrays, it takes an array of strings and puts
 * a backslash in front of every character that is part of the regular
 * expression syntax.
 *
 * @param  array $array    input array
 * @param  array $delim    optional character that will also be escaped.
 * @return array    an array with the same values as $array1 but shuffled
 */
function pregQuoteArray($array, $delim='/')
{
    if (!empty($array)) {
        if (is_array($array)) {
            foreach ($array as $key=>$val) {
                $quoted_array[$key] = preg_quote($val, $delim);
            }
            return $quoted_array;
        } else {
            return preg_quote($array, $delim);
        }
    }
}

/**
 * Converts a PHP Array into encoded URL arguments and return them as an array.
 *
 * @param  mixed $data        An array to transverse recursively, or a string
 *                            to use directly to create url arguments.
 * @param  string $prefix     The name of the first dimension of the array.
 *                            If not specified, the first keys of the array will be used.
 * @return array              URL with array elements as URL key=value arguments.
 */
function urlEncodeArray($data, $prefix='', $_return=true)
{

    // Data is stored in static variable.
    static $args;

    if (is_array($data)) {
        foreach ($data as $key => $val) {
            // If the prefix is empty, use the $key as the name of the first dimension of the "array".
            // ...otherwise, append the key as a new dimension of the "array".
            $new_prefix = ('' == $prefix) ? urlencode($key) : $prefix . '[' . urlencode($key) . ']';
            // Enter recursion.
            urlEncodeArray($val, $new_prefix, false);
        }
    } else {
        // We've come to the last dimension of the array, save the "array" and its value.
        $args[$prefix] = urlencode($data);
    }

    if ($_return) {
        // This is not a recursive execution. All recursion is complete.
        // Reset static var and return the result.
        $ret = $args;
        $args = array();
        return is_array($ret) ? $ret : array();
    }
}

/**
 * Converts a PHP Array into encoded URL arguments and return them in a string.
 *
 * @param  mixed $data        An array to transverse recursively, or a string
 *                            to use directly to create url arguments.
 * @param  string $prefix     The name of the first dimension of the array.
 *                            If not specified, the first keys of the array will be used.
 * @return string url         A string ready to append to a url.
 */
function urlEncodeArrayToString($data, $prefix='')
{

    $array_args = urlEncodeArray($data, $prefix);
    $url_args = '';
    $delim = '';
    foreach ($array_args as $key=>$val) {
        $url_args .= $delim . $key . '=' . $val;
        $delim = ini_get('arg_separator.output');
    }
    return $url_args;
}

/**
 * Fills an array with the result from a multiple ereg search.
 * Courtesy of Bruno - rbronosky@mac.com - 10-May-2001
 *
 * @param  mixed $pattern   regular expression needle
 * @param  mixed $string   haystack
 * @return array    populated with each found result
 */
function eregAll($pattern, $string)
{
    do {
        if (!mb_ereg($pattern, $string, $temp)) {
             continue;
        }
        $string = str_replace($temp[0], '', $string);
        $results[] = $temp;
    } while (mb_ereg($pattern, $string, $temp));
    return $results;
}

/**
 * Prints the word "checked" if a variable is set, and optionally matches
 * the desired value, otherwise prints nothing,
 * used for printing the word "checked" in a checkbox form input.
 *
 * @param  mixed $var     the variable to compare
 * @param  mixed $value   optional, what to compare with if a specific value is required.
 */
function frmChecked($var, $value=null)
{
    if (func_num_args() == 1 && $var) {
        // 'Checked' if var is true.
        echo ' checked="checked" ';
    } else if (func_num_args() == 2 && $var == $value) {
        // 'Checked' if var and value match.
        echo ' checked="checked" ';
    } else if (func_num_args() == 2 && is_array($var)) {
        // 'Checked' if the value is in the key or the value of an array.
        if (isset($var[$value])) {
            echo ' checked="checked" ';
        } else if (in_array($value, $var)) {
            echo ' checked="checked" ';
        }
    }
}

/**
 * prints the word "selected" if a variable is set, and optionally matches
 * the desired value, otherwise prints nothing,
 * otherwise prints nothing, used for printing the word "checked" in a
 * select form input
 *
 * @param  mixed $var     the variable to compare
 * @param  mixed $value   optional, what to compare with if a specific value is required.
 */
function frmSelected($var, $value=null)
{
    if (func_num_args() == 1 && $var) {
        // 'selected' if var is true.
        echo ' selected="selected" ';
    } else if (func_num_args() == 2 && $var == $value) {
        // 'selected' if var and value match.
        echo ' selected="selected" ';
    } else if (func_num_args() == 2 && is_array($var)) {
        // 'selected' if the value is in the key or the value of an array.
        if (isset($var[$value])) {
            echo ' selected="selected" ';
        } else if (in_array($value, $var)) {
            echo ' selected="selected" ';
        }
    }
}

/**
 * Adds slashes to values of an array and converts the array to a comma
 * delimited list. If value provided is a string return the string
 * escaped.  This is useful for putting values coming in from posted
 * checkboxes into a SET column of a database.
 * 
 *
 * @param  array $in      Array to convert.
 * @return string         Comma list of array values.
 */
function escapedList($in, $separator="', '")
{
    $db =& DB::getInstance();
    
    if (is_array($in) && !empty($in)) {
        return join($separator, array_map(array($db, 'escapeString'), $in));
    } else {
        return $db->escapeString($in);
    }
}

/**
 * Converts a human string date into a SQL-safe date.  Dates nearing
 * infinity use the date 2038-01-01 so conversion to unix time format
 * remain within valid range.
 *
 * @param  array $date     String date to convert.
 * @param  array $format   Date format to pass to date().
 *                         Default produces MySQL datetime: 0000-00-00 00:00:00.
 * @return string          SQL-safe date.
 */
function strToSQLDate($date, $format='Y-m-d H:i:s')
{
    // Translate the human string date into SQL-safe date format.
    if (empty($date) || mb_strpos($date, '0000-00-00') !== false || strtotime($date) === -1 || strtotime($date) === false) {
        // Return a string of zero time, formatted the same as $format.
        return strtr($format, array(
            'Y' => '0000',
            'm' => '00',
            'd' => '00',
            'H' => '00',
            'i' => '00',
            's' => '00',
        ));
    } else {
        return date($format, strtotime($date));
    }
}

/**
 * If magic_quotes_gpc is in use, run stripslashes() on $var. If $var is an
 * array, stripslashes is run on each value, recursively, and the stripped
 * array is returned.
 *
 * @param  mixed $var   The string or array to un-quote, if necessary.
 * @return mixed        $var, minus any magic quotes.
 */
function dispelMagicQuotes($var)
{
    static $magic_quotes_gpc;

    if (!isset($magic_quotes_gpc)) {
        $magic_quotes_gpc = get_magic_quotes_gpc();
    }

    if ($magic_quotes_gpc) {
        if (!is_array($var)) {
            $var = stripslashes($var);
        } else {
            foreach ($var as $key=>$val) {
                if (is_array($val)) {
                    $var[$key] = dispelMagicQuotes($val);
                } else {
                    $var[$key] = stripslashes($val);
                }
            }
        }
    }
    return $var;
}

/**
 * Get a form variable from GET or POST data, stripped of magic
 * quotes if necessary.
 *
 * @param string $var (optional) The name of the form variable to look for.
 * @param string $default (optional) The value to return if the
 *                                   variable is not there.
 * @return mixed      A cleaned GET or POST if no $var specified.
 * @return string     A cleaned form $var if found, or $default.
 */
function getFormData($var=null, $default=null)
{
    if ('POST' == getenv('REQUEST_METHOD') && is_null($var)) {
        return dispelMagicQuotes($_POST);
    } else if ('GET' == getenv('REQUEST_METHOD') && is_null($var)) {
        return dispelMagicQuotes($_GET);
    }
    if (isset($_POST[$var])) {
        return dispelMagicQuotes($_POST[$var]);
    } else if (isset($_GET[$var])) {
        return dispelMagicQuotes($_GET[$var]);
    } else {
        return $default;
    }
}
function getPost($var=null, $default=null)
{
    if (is_null($var)) {
        return dispelMagicQuotes($_POST);
    }
    if (isset($_POST[$var])) {
        return dispelMagicQuotes($_POST[$var]);
    } else {
        return $default;
    }
}
function getGet($var=null, $default=null)
{
    if (is_null($var)) {
        return dispelMagicQuotes($_GET);
    }
    if (isset($_GET[$var])) {
        return dispelMagicQuotes($_GET[$var]);
    } else {
        return $default;
    }
}

/**
 * Signs a value using md5 and a simple text key. In order for this
 * function to be useful (i.e. secure) the key must be kept secret, which
 * means keeping it as safe as database credentials. Putting it into an
 * environment variable set in httpd.conf is a good place.
 *
 * @access  public
 * @param   string  $val    The string to sign.
 * @param   string  $salt   (Optional) A text key to use for computing the signature.
 * @param   string  $length (Optional) The length of the added signature. Longer signatures are safer. Must match the length passed to verifySignature() for the signatures to match.
 * @return  string  The original value with a signature appended.
 */
function addSignature($val, $salt=null, $length=18)
{
    $app =& App::getInstance();
    
    if ('' == trim($val)) {
        $app->logMsg(sprintf('Cannot add signature to an empty string.', null), LOG_INFO, __FILE__, __LINE__);
        return '';
    }

    if (!isset($salt)) {
        $salt = $app->getParam('signing_key');
    }

    return $val . '-' . mb_strtolower(mb_substr(md5($salt . md5($val . $salt)), 0, $length));
}

/**
 * Strips off the signature appended by addSignature().
 *
 * @access  public
 * @param   string  $signed_val     The string to sign.
 * @return  string  The original value with a signature removed.
 */
function removeSignature($signed_val)
{
    if (empty($signed_val) || mb_strpos($signed_val, '-') === false) {
        return '';
    }
    return mb_substr($signed_val, 0, mb_strrpos($signed_val, '-'));
}


/**
 * Verifies a signature appened to a value by addSignature().
 *
 * @access  public
 * @param   string  $signed_val A value with appended signature.
 * @param   string  $salt       (Optional) A text key to use for computing the signature.
 * @return  bool    True if the signature matches the var.
 */
function verifySignature($signed_val, $salt=null, $length=18)
{
    // All comparisons are done using lower-case strings.
    $signed_val = mb_strtolower($signed_val);
    // Strip the value from the signed value.
    $val = removeSignature($signed_val);
    // If the signed value matches the original signed value we consider the value safe.
    if ($signed_val == addSignature($val, $salt, $length)) {
        // Signature verified.
        return true;
    } else {
        return false;
    }
}

/**
 * Sends empty output to the browser and flushes the php buffer so the client
 * will see data before the page is finished processing.
 */
function flushBuffer()
{
    echo str_repeat('          ', 205);
    flush();
}

/**
 * Adds email address to mailman mailing list. Requires /etc/sudoers entry for apache to sudo execute add_members.
 * Don't forget to allow php_admin_value open_basedir access to "/var/mailman/bin".
 *
 * @access  public
 * @param   string  $email     Email address to add.
 * @param   string  $list      Name of list to add to.
 * @param   bool    $send_welcome_message   True to send welcome message to subscriber.
 * @return  bool    True on success, false on failure.
 */
function mailmanAddMember($email, $list, $send_welcome_message=false)
{
    $app =& App::getInstance();
    
    $add_members = '/usr/lib/mailman/bin/add_members';
    /// FIXME: checking of executable is disabled.
    if (true || is_executable($add_members) && is_readable($add_members)) {
        $welcome_msg = $send_welcome_message ? 'y' : 'n';
        exec(sprintf("/bin/echo '%s' | /usr/bin/sudo %s -r - --welcome-msg=%s --admin-notify=n '%s'", escapeshellarg($email), escapeshellarg($add_members), $welcome_msg, escapeshellarg($list)), $stdout, $return_code);
        if (0 == $return_code) {
            $app->logMsg(sprintf('Mailman add member success for list: %s, user: %s', $list, $email, $stdout), LOG_INFO, __FILE__, __LINE__);
            return true;
        } else {
            $app->logMsg(sprintf('Mailman add member failed for list: %s, user: %s, with message: %s', $list, $email, $stdout), LOG_WARNING, __FILE__, __LINE__);
            return false;
        }
    } else {
        $app->logMsg(sprintf('Mailman add member program not executable: %s', $add_members), LOG_ALERT, __FILE__, __LINE__);
        return false;
    }
}

/**
 * Removes email address from mailman mailing list. Requires /etc/sudoers entry for apache to sudo execute add_members.
 * Don't forget to allow php_admin_value open_basedir access to "/var/mailman/bin".
 *
 * @access  public
 * @param   string  $email     Email address to add.
 * @param   string  $list      Name of list to add to.
 * @param   bool    $send_user_ack   True to send goodbye message to subscriber.
 * @return  bool    True on success, false on failure.
 */
function mailmanRemoveMember($email, $list, $send_user_ack=false)
{
    $app =& App::getInstance();
    
    $remove_members = '/usr/lib/mailman/bin/remove_members';
    /// FIXME: checking of executable is disabled.
    if (true || is_executable($remove_members) && is_readable($remove_members)) {
        $userack = $send_user_ack ? '' : '--nouserack';
        exec(sprintf("/usr/bin/sudo %s %s --noadminack '%s' '%s'", escapeshellarg($remove_members), $userack, escapeshellarg($list), escapeshellarg($email)), $stdout, $return_code);
        if (0 == $return_code) {
            $app->logMsg(sprintf('Mailman remove member success for list: %s, user: %s', $list, $email, $stdout), LOG_INFO, __FILE__, __LINE__);
            return true;
        } else {
            $app->logMsg(sprintf('Mailman remove member failed for list: %s, user: %s, with message: %s', $list, $email, $stdout), LOG_WARNING, __FILE__, __LINE__);
            return false;
        }
    } else {
        $app->logMsg(sprintf('Mailman remove member program not executable: %s', $remove_members), LOG_ALERT, __FILE__, __LINE__);
        return false;
    }
}

/**
 * Returns the remote IP address, taking into consideration proxy servers.
 *
 * @param  bool $dolookup   If true we resolve to IP to a host name,
 *                          if false we don't.
 * @return string    IP address if $dolookup is false or no arg
 *                   Hostname if $dolookup is true
 */
function getRemoteAddr($dolookup=false)
{
    $ip = getenv('HTTP_CLIENT_IP');
    if (in_array($ip, array('', 'unknown', 'localhost', '127.0.0.1'))) {
        $ip = getenv('HTTP_X_FORWARDED_FOR');
        if (mb_strpos($ip, ',') !== false) {
            // If HTTP_X_FORWARDED_FOR returns a comma-delimited list of IPs then return the first one (assuming the first is the original).
            $ips = explode(',', $ip, 2);
            $ip = $ips[0];
        }
        if (in_array($ip, array('', 'unknown', 'localhost', '127.0.0.1'))) {
            $ip = getenv('REMOTE_ADDR');
        }
    }
    return $dolookup && '' != $ip ? gethostbyaddr($ip) : $ip;
}

/**
 * Tests whether a given IP address can be found in an array of IP address networks.
 * Elements of networks array can be single IP addresses or an IP address range in CIDR notation
 * See: http://en.wikipedia.org/wiki/Classless_inter-domain_routing
 *
 * @access  public
 * @param   string  IP address to search for.
 * @param   array   Array of networks to search within.
 * @return  mixed   Returns the network that matched on success, false on failure.
 */
function ipInRange($ip, $networks)
{
    if (!is_array($networks)) {
        $networks = array($networks);
    }

    $ip_binary = sprintf('%032b', ip2long($ip));
    foreach ($networks as $network) {
        if (preg_match('![\d\.]{7,15}/\d{1,2}!', $network)) {
            // IP is in CIDR notation.
            list($cidr_ip, $cidr_bitmask) = explode('/', $network);
            $cidr_ip_binary = sprintf('%032b', ip2long($cidr_ip));
            if (mb_substr($ip_binary, 0, $cidr_bitmask) === mb_substr($cidr_ip_binary, 0, $cidr_bitmask)) {
               // IP address is within the specified IP range.
               return $network;
            }
        } else {
            if ($ip === $network) {
               // IP address exactly matches.
               return $network;
            }
        }
    }

    return false;
}

/**
 * If the given $url is on the same web site, return true. This can be used to
 * prevent from sending sensitive info in a get query (like the SID) to another
 * domain.
 *
 * @param  string $url    the URI to test.
 * @return bool True if given $url is our domain or has no domain (is a relative url), false if it's another.
 */
function isMyDomain($url)
{
    static $urls = array();

    if (!isset($urls[$url])) {
        if (!preg_match('|https?://[\w.]+/|', $url)) {
            // If we can't find a domain we assume the URL is local (i.e. "/my/url/path/" or "../img/file.jpg").
            $urls[$url] = true;
        } else {
            $urls[$url] = preg_match('|https?://[\w.]*' . preg_quote(getenv('HTTP_HOST'), '|') . '|i', $url);
        }
    }
    return $urls[$url];
}

/**
 * Takes a URL and returns it without the query or anchor portion
 *
 * @param  string $url   any kind of URI
 * @return string        the URI with ? or # and everything after removed
 */
function stripQuery($url)
{
    return preg_replace('/[?#].*$/', '', $url);
}

/**
 * Returns a fully qualified URL to the current script, including the query.
 *
 * @return string    a full url to the current script
 */
function absoluteMe()
{
    $protocol = ('on' == getenv('HTTPS')) ? 'https://' : 'http://';
    return $protocol . getenv('HTTP_HOST') . getenv('REQUEST_URI');
}

/**
 * Compares the current url with the referring url.
 *
 * @param  bool $exclude_query  Remove the query string first before comparing.
 * @return bool                 True if the current URL is the same as the referring URL, false otherwise.
 */
function refererIsMe($exclude_query=false)
{
    if ($exclude_query) {
        return (stripQuery(absoluteMe()) == stripQuery(getenv('HTTP_REFERER')));
    } else {
        return (absoluteMe() == getenv('HTTP_REFERER'));
    }
}

/**
 * Stub functions used when installation does not have
 * GNU gettext extension installed
 */
if (!extension_loaded('gettext')) {
    /**
    * Translates text
    *
    * @access public
    * @param string $text the text to be translated
    * @return string translated text
    */
    function gettext($text) {
        return $text;
    }

    /**
    * Translates text
    *
    * @access public
    * @param string $text the text to be translated
    * @return string translated text
    */
    function _($text) {
        return $text;
    }

    /**
    * Translates text by domain
    *
    * @access public
    * @param string $domain the language to translate the text into
    * @param string $text the text to be translated
    * @return string translated text
    */
    function dgettext($domain, $text) {
        return $text;
    }

    /**
    * Translates text by domain and category
    *
    * @access public
    * @param string $domain the language to translate the text into
    * @param string $text the text to be translated
    * @param string $category the language dialect to use
    * @return string translated text
    */
    function dcgettext($domain, $text, $category) {
        return $text;
    }

    /**
    * Binds the text domain
    *
    * @access public
    * @param string $domain the language to translate the text into
    * @param string
    * @return string translated text
    */
    function bindtextdomain($domain, $directory) {
        return $domain;
    }

    /**
    * Sets the text domain
    *
    * @access public
    * @param string $domain the language to translate the text into
    * @return string translated text
    */
    function textdomain($domain) {
        return $domain;
    }
}



?>