S2OJ/web/app/vendor/htmlpurifier/HTMLPurifier/Lexer/DirectLex.php
Masco Skray 96d4a3ecf7 style(judger,web): move code out from subfolder "1"
Due to historical reasons, the code is in subfolder "1".
With SVN removal, we place the code back and remove the annoying "1" folder.
2019-06-14 23:34:41 +08:00

540 lines
20 KiB
PHP

<?php
/**
* Our in-house implementation of a parser.
*
* A pure PHP parser, DirectLex has absolutely no dependencies, making
* it a reasonably good default for PHP4. Written with efficiency in mind,
* it can be four times faster than HTMLPurifier_Lexer_PEARSax3, although it
* pales in comparison to HTMLPurifier_Lexer_DOMLex.
*
* @todo Reread XML spec and document differences.
*/
class HTMLPurifier_Lexer_DirectLex extends HTMLPurifier_Lexer
{
/**
* @type bool
*/
public $tracksLineNumbers = true;
/**
* Whitespace characters for str(c)spn.
* @type string
*/
protected $_whitespace = "\x20\x09\x0D\x0A";
/**
* Callback function for script CDATA fudge
* @param array $matches, in form of array(opening tag, contents, closing tag)
* @return string
*/
protected function scriptCallback($matches)
{
return $matches[1] . htmlspecialchars($matches[2], ENT_COMPAT, 'UTF-8') . $matches[3];
}
/**
* @param String $html
* @param HTMLPurifier_Config $config
* @param HTMLPurifier_Context $context
* @return array|HTMLPurifier_Token[]
*/
public function tokenizeHTML($html, $config, $context)
{
// special normalization for script tags without any armor
// our "armor" heurstic is a < sign any number of whitespaces after
// the first script tag
if ($config->get('HTML.Trusted')) {
$html = preg_replace_callback(
'#(<script[^>]*>)(\s*[^<].+?)(</script>)#si',
array($this, 'scriptCallback'),
$html
);
}
$html = $this->normalize($html, $config, $context);
$cursor = 0; // our location in the text
$inside_tag = false; // whether or not we're parsing the inside of a tag
$array = array(); // result array
// This is also treated to mean maintain *column* numbers too
$maintain_line_numbers = $config->get('Core.MaintainLineNumbers');
if ($maintain_line_numbers === null) {
// automatically determine line numbering by checking
// if error collection is on
$maintain_line_numbers = $config->get('Core.CollectErrors');
}
if ($maintain_line_numbers) {
$current_line = 1;
$current_col = 0;
$length = strlen($html);
} else {
$current_line = false;
$current_col = false;
$length = false;
}
$context->register('CurrentLine', $current_line);
$context->register('CurrentCol', $current_col);
$nl = "\n";
// how often to manually recalculate. This will ALWAYS be right,
// but it's pretty wasteful. Set to 0 to turn off
$synchronize_interval = $config->get('Core.DirectLexLineNumberSyncInterval');
$e = false;
if ($config->get('Core.CollectErrors')) {
$e =& $context->get('ErrorCollector');
}
// for testing synchronization
$loops = 0;
while (++$loops) {
// $cursor is either at the start of a token, or inside of
// a tag (i.e. there was a < immediately before it), as indicated
// by $inside_tag
if ($maintain_line_numbers) {
// $rcursor, however, is always at the start of a token.
$rcursor = $cursor - (int)$inside_tag;
// Column number is cheap, so we calculate it every round.
// We're interested at the *end* of the newline string, so
// we need to add strlen($nl) == 1 to $nl_pos before subtracting it
// from our "rcursor" position.
$nl_pos = strrpos($html, $nl, $rcursor - $length);
$current_col = $rcursor - (is_bool($nl_pos) ? 0 : $nl_pos + 1);
// recalculate lines
if ($synchronize_interval && // synchronization is on
$cursor > 0 && // cursor is further than zero
$loops % $synchronize_interval === 0) { // time to synchronize!
$current_line = 1 + $this->substrCount($html, $nl, 0, $cursor);
}
}
$position_next_lt = strpos($html, '<', $cursor);
$position_next_gt = strpos($html, '>', $cursor);
// triggers on "<b>asdf</b>" but not "asdf <b></b>"
// special case to set up context
if ($position_next_lt === $cursor) {
$inside_tag = true;
$cursor++;
}
if (!$inside_tag && $position_next_lt !== false) {
// We are not inside tag and there still is another tag to parse
$token = new
HTMLPurifier_Token_Text(
$this->parseData(
substr(
$html,
$cursor,
$position_next_lt - $cursor
)
)
);
if ($maintain_line_numbers) {
$token->rawPosition($current_line, $current_col);
$current_line += $this->substrCount($html, $nl, $cursor, $position_next_lt - $cursor);
}
$array[] = $token;
$cursor = $position_next_lt + 1;
$inside_tag = true;
continue;
} elseif (!$inside_tag) {
// We are not inside tag but there are no more tags
// If we're already at the end, break
if ($cursor === strlen($html)) {
break;
}
// Create Text of rest of string
$token = new
HTMLPurifier_Token_Text(
$this->parseData(
substr(
$html,
$cursor
)
)
);
if ($maintain_line_numbers) {
$token->rawPosition($current_line, $current_col);
}
$array[] = $token;
break;
} elseif ($inside_tag && $position_next_gt !== false) {
// We are in tag and it is well formed
// Grab the internals of the tag
$strlen_segment = $position_next_gt - $cursor;
if ($strlen_segment < 1) {
// there's nothing to process!
$token = new HTMLPurifier_Token_Text('<');
$cursor++;
continue;
}
$segment = substr($html, $cursor, $strlen_segment);
if ($segment === false) {
// somehow, we attempted to access beyond the end of
// the string, defense-in-depth, reported by Nate Abele
break;
}
// Check if it's a comment
if (substr($segment, 0, 3) === '!--') {
// re-determine segment length, looking for -->
$position_comment_end = strpos($html, '-->', $cursor);
if ($position_comment_end === false) {
// uh oh, we have a comment that extends to
// infinity. Can't be helped: set comment
// end position to end of string
if ($e) {
$e->send(E_WARNING, 'Lexer: Unclosed comment');
}
$position_comment_end = strlen($html);
$end = true;
} else {
$end = false;
}
$strlen_segment = $position_comment_end - $cursor;
$segment = substr($html, $cursor, $strlen_segment);
$token = new
HTMLPurifier_Token_Comment(
substr(
$segment,
3,
$strlen_segment - 3
)
);
if ($maintain_line_numbers) {
$token->rawPosition($current_line, $current_col);
$current_line += $this->substrCount($html, $nl, $cursor, $strlen_segment);
}
$array[] = $token;
$cursor = $end ? $position_comment_end : $position_comment_end + 3;
$inside_tag = false;
continue;
}
// Check if it's an end tag
$is_end_tag = (strpos($segment, '/') === 0);
if ($is_end_tag) {
$type = substr($segment, 1);
$token = new HTMLPurifier_Token_End($type);
if ($maintain_line_numbers) {
$token->rawPosition($current_line, $current_col);
$current_line += $this->substrCount($html, $nl, $cursor, $position_next_gt - $cursor);
}
$array[] = $token;
$inside_tag = false;
$cursor = $position_next_gt + 1;
continue;
}
// Check leading character is alnum, if not, we may
// have accidently grabbed an emoticon. Translate into
// text and go our merry way
if (!ctype_alpha($segment[0])) {
// XML: $segment[0] !== '_' && $segment[0] !== ':'
if ($e) {
$e->send(E_NOTICE, 'Lexer: Unescaped lt');
}
$token = new HTMLPurifier_Token_Text('<');
if ($maintain_line_numbers) {
$token->rawPosition($current_line, $current_col);
$current_line += $this->substrCount($html, $nl, $cursor, $position_next_gt - $cursor);
}
$array[] = $token;
$inside_tag = false;
continue;
}
// Check if it is explicitly self closing, if so, remove
// trailing slash. Remember, we could have a tag like <br>, so
// any later token processing scripts must convert improperly
// classified EmptyTags from StartTags.
$is_self_closing = (strrpos($segment, '/') === $strlen_segment - 1);
if ($is_self_closing) {
$strlen_segment--;
$segment = substr($segment, 0, $strlen_segment);
}
// Check if there are any attributes
$position_first_space = strcspn($segment, $this->_whitespace);
if ($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) {
$token->rawPosition($current_line, $current_col);
$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) {
$token->rawPosition($current_line, $current_col);
$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) {
$token->rawPosition($current_line, $current_col);
}
// no cursor scroll? Hmm...
$array[] = $token;
break;
}
break;
}
$context->destroy('CurrentLine');
$context->destroy('CurrentCol');
return $array;
}
/**
* PHP 5.0.x compatible substr_count that implements offset and length
* @param string $haystack
* @param string $needle
* @param int $offset
* @param int $length
* @return int
*/
protected function substrCount($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 $string Inside of tag excluding name.
* @param HTMLPurifier_Config $config
* @param HTMLPurifier_Context $context
* @return array Assoc array of attributes.
*/
public function parseAttributeString($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 => $this->parseData($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 .= ' ';
$old_cursor = -1;
while ($cursor < $size) {
if ($old_cursor >= $cursor) {
throw new Exception("Infinite loop detected");
}
$old_cursor = $cursor;
$cursor += ($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');
}
$cursor += 1 + strcspn($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;
}
}
// vim: et sw=4 sts=4