A better PHP trim() function

trim_better.php

/**
 * trims text to a maximum length, splitting at last word break, and (optionally) appending ellipses and stripping HTML tags
 * @param string $input text to trim
 * @param int $length maximum number of characters allowed
 * @param bool $ellipses if ellipses (...) are to be added
 * @param bool $strip_html if html tags are to be stripped
 * @return string 
 */
function trim_better($input, $length, $ellipses = true, $strip_html = true) {
    //strip tags, if desired
    if ($strip_html) {
        $input = strip_tags($input);
    }
 
    //strip leading and trailing whitespace
    $input = trim($input);
 
    //no need to trim, already shorter than trim length
    if (strlen($input) <= $length) {
        return $input;
    }
 
    //leave space for the ellipses (...)
    if ($ellipses) {
        $length -= 3;
    }
 
    //this would be dumb, but I've seen dumber
    if ($length <= 0) {
        return '';
    }
 
    //find last space within length
    //(add 1 to length to allow space after last character - it may be your lucky day)
    $last_space = strrpos(substr($input, 0, $length + 1), ' ');
    if ($last_space === false) {
        //lame, no spaces - fallback to pure substring
        $trimmed_text = substr($input, 0, $length);
    }
    else {
        //found last space, trim to it
        $trimmed_text = substr($input, 0, $last_space);
    }
 
    //add ellipses (...)
    if ($ellipses) {
        $trimmed_text .= '...';
    }
 
    return $trimmed_text;
}