directlex.php

很棒的在线教学系统

                
                if ($position_first_space >= $strlen_segment) {
                    if ($is_self_closing) {
                        $token = new HTMLPurifier_Token_Empty($segment);
                    } else {
                        $token = new HTMLPurifier_Token_Start($segment);
                    }
                    if ($maintain_line_numbers) {
                        $token->line = $current_line;
                        $current_line += $this->substrCount($html, $nl, $cursor, $position_next_gt - $cursor);
                    }
                    $array[] = $token;
                    $inside_tag = false;
                    $cursor = $position_next_gt + 1;
                    continue;
                }
                
                // Grab out all the data
                $type = substr($segment, 0, $position_first_space);
                $attribute_string =
                    trim(
                        substr(
                            $segment, $position_first_space
                        )
                    );
                if ($attribute_string) {
                    $attr = $this->parseAttributeString(
                                    $attribute_string
                                  , $config, $context
                              );
                } else {
                    $attr = array();
                }
                
                if ($is_self_closing) {
                    $token = new HTMLPurifier_Token_Empty($type, $attr);
                } else {
                    $token = new HTMLPurifier_Token_Start($type, $attr);
                }
                if ($maintain_line_numbers) {
                    $token->line = $current_line;
                    $current_line += $this->substrCount($html, $nl, $cursor, $position_next_gt - $cursor);
                }
                $array[] = $token;
                $cursor = $position_next_gt + 1;
                $inside_tag = false;
                continue;
            } else {
                // inside tag, but there's no ending > sign
                if ($e) $e->send(E_WARNING, 'Lexer: Missing gt');
                $token = new
                    HTMLPurifier_Token_Text(
                        '<' .
                        $this->parseData(
                            substr($html, $cursor)
                        )
                    );
                if ($maintain_line_numbers) $token->line = $current_line;
                // no cursor scroll? Hmm...
                $array[] = $token;
                break;
            }
            break;
        }
        
        $context->destroy('CurrentLine');
        return $array;
    }
    
    /**
     * PHP 4 compatible substr_count that implements offset and length
     */
    function substrCount($haystack, $needle, $offset, $length) {
        static $oldVersion;
        if ($oldVersion === null) {
            $oldVersion = version_compare(PHP_VERSION, '5.1', '<');
        }
        if ($oldVersion) {
            $haystack = substr($haystack, $offset, $length);
            return substr_count($haystack, $needle);
        } else {
            return substr_count($haystack, $needle, $offset, $length);
        }
    }
    
    /**
     * Takes the inside of an HTML tag and makes an assoc array of attributes.
     * 
     * @param $string Inside of tag excluding name.
     * @returns Assoc array of attributes.
     */
    function parseAttributeString($string, $config, &$context) {
        $string = (string) $string; // quick typecast
        
        if ($string == '') return array(); // no attributes
        
        $e = false;
        if ($config->get('Core', 'CollectErrors')) {
            $e =& $context->get('ErrorCollector');
        }
        
        // let's see if we can abort as quickly as possible
        // one equal sign, no spaces => one attribute
        $num_equal = substr_count($string, '=');
        $has_space = strpos($string, ' ');
        if ($num_equal === 0 && !$has_space) {
            // bool attribute
            return array($string => $string);
        } elseif ($num_equal === 1 && !$has_space) {
            // only one attribute
            list($key, $quoted_value) = explode('=', $string);
            $quoted_value = trim($quoted_value);
            if (!$key) {
                if ($e) $e->send(E_ERROR, 'Lexer: Missing attribute key');
                return array();
            }
            if (!$quoted_value) return array($key => '');
            $first_char = @$quoted_value[0];
            $last_char  = @$quoted_value[strlen($quoted_value)-1];
            
            $same_quote = ($first_char == $last_char);
            $open_quote = ($first_char == '"' || $first_char == "'");
            
            if ( $same_quote && $open_quote) {
                // well behaved
                $value = substr($quoted_value, 1, strlen($quoted_value) - 2);
            } else {
                // not well behaved
                if ($open_quote) {
                    if ($e) $e->send(E_ERROR, 'Lexer: Missing end quote');
                    $value = substr($quoted_value, 1);
                } else {
                    $value = $quoted_value;
                }
            }
            if ($value === false) $value = '';
            return array($key => $value);
        }
        
        // setup loop environment
        $array  = array(); // return assoc array of attributes
        $cursor = 0; // current position in string (moves forward)
        $size   = strlen($string); // size of the string (stays the same)
        
        // if we have unquoted attributes, the parser expects a terminating
        // space, so let's guarantee that there's always a terminating space.
        $string .= ' ';
        
        // infinite loop protection
        $loops = 0;
        while(true) {
            
            // infinite loop protection
            if (++$loops > 1000) {
                trigger_error('Infinite loop detected in attribute parsing', E_USER_WARNING);
                return array();
            }
            
            if ($cursor >= $size) {
                break;
            }
            
            $cursor += ($value = strspn($string, $this->_whitespace, $cursor));
            // grab the key
            
            $key_begin = $cursor; //we're currently at the start of the key
            
            // scroll past all characters that are the key (not whitespace or =)
            $cursor += strcspn($string, $this->_whitespace . '=', $cursor);
            
            $key_end = $cursor; // now at the end of the key
            
            $key = substr($string, $key_begin, $key_end - $key_begin);
            
            if (!$key) {
                if ($e) $e->send(E_ERROR, 'Lexer: Missing attribute key');
                $cursor += strcspn($string, $this->_whitespace, $cursor + 1); // prevent infinite loop
                continue; // empty key
            }
            
            // scroll past all whitespace
            $cursor += strspn($string, $this->_whitespace, $cursor);
            
            if ($cursor >= $size) {
                $array[$key] = $key;
                break;
            }
            
            // if the next character is an equal sign, we've got a regular
            // pair, otherwise, it's a bool attribute
            $first_char = @$string[$cursor];
            
            if ($first_char == '=') {
                // key="value"
                
                $cursor++;
                $cursor += strspn($string, $this->_whitespace, $cursor);
                
                if ($cursor === false) {
                    $array[$key] = '';
                    break;
                }
                
                // we might be in front of a quote right now
                
                $char = @$string[$cursor];
                
                if ($char == '"' || $char == "'") {
                    // it's quoted, end bound is $char
                    $cursor++;
                    $value_begin = $cursor;
                    $cursor = strpos($string, $char, $cursor);
                    $value_end = $cursor;
                } else {
                    // it's not quoted, end bound is whitespace
                    $value_begin = $cursor;
                    $cursor += strcspn($string, $this->_whitespace, $cursor);
                    $value_end = $cursor;
                }
                
                // we reached a premature end
                if ($cursor === false) {
                    $cursor = $size;
                    $value_end = $cursor;
                }
                
                $value = substr($string, $value_begin, $value_end - $value_begin);
                if ($value === false) $value = '';
                $array[$key] = $this->parseData($value);
                $cursor++;
                
            } else {
                // boolattr
                if ($key !== '') {
                    $array[$key] = $key;
                } else {
                    // purely theoretical
                    if ($e) $e->send(E_ERROR, 'Lexer: Missing attribute key');
                }
                
            }
        }
        return $array;
    }
    
}