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-rw-r--r--lib/querypath/src/QueryPath/CSS/Scanner.php306
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diff --git a/lib/querypath/src/QueryPath/CSS/Scanner.php b/lib/querypath/src/QueryPath/CSS/Scanner.php
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+<?php
+/** @file
+ * The scanner.
+ */
+namespace QueryPath\CSS;
+/**
+ * Scanner for CSS selector parsing.
+ *
+ * This provides a simple scanner for traversing an input stream.
+ *
+ * @ingroup querypath_css
+ */
+final class Scanner {
+ var $is = NULL;
+ public $value = NULL;
+ public $token = NULL;
+
+ var $recurse = FALSE;
+ var $it = 0;
+
+ /**
+ * Given a new input stream, tokenize the CSS selector string.
+ * @see InputStream
+ * @param InputStream $in
+ * An input stream to be scanned.
+ */
+ public function __construct(InputStream $in) {
+ $this->is = $in;
+ }
+
+ /**
+ * Return the position of the reader in the string.
+ */
+ public function position() {
+ return $this->is->position;
+ }
+
+ /**
+ * See the next char without removing it from the stack.
+ *
+ * @return char
+ * Returns the next character on the stack.
+ */
+ public function peek() {
+ return $this->is->peek();
+ }
+
+ /**
+ * Get the next token in the input stream.
+ *
+ * This sets the current token to the value of the next token in
+ * the stream.
+ *
+ * @return int
+ * Returns an int value corresponding to one of the Token constants,
+ * or FALSE if the end of the string is reached. (Remember to use
+ * strong equality checking on FALSE, since 0 is a valid token id.)
+ */
+ public function nextToken() {
+ $tok = -1;
+ ++$this->it;
+ if ($this->is->isEmpty()) {
+ if ($this->recurse) {
+ throw new \QueryPath\Exception("Recursion error detected at iteration " . $this->it . '.');
+ exit();
+ }
+ //print "{$this->it}: All done\n";
+ $this->recurse = TRUE;
+ $this->token = FALSE;
+ return FALSE;
+ }
+ $ch = $this->is->consume();
+ //print __FUNCTION__ . " Testing $ch.\n";
+ if (ctype_space($ch)) {
+ $this->value = ' '; // Collapse all WS to a space.
+ $this->token = $tok = Token::white;
+ //$ch = $this->is->consume();
+ return $tok;
+ }
+
+ if (ctype_alnum($ch) || $ch == '-' || $ch == '_') {
+ // It's a character
+ $this->value = $ch; //strtolower($ch);
+ $this->token = $tok = Token::char;
+ return $tok;
+ }
+
+ $this->value = $ch;
+
+ switch($ch) {
+ case '*':
+ $tok = Token::star;
+ break;
+ case chr(ord('>')):
+ $tok = Token::rangle;
+ break;
+ case '.':
+ $tok = Token::dot;
+ break;
+ case '#':
+ $tok = Token::octo;
+ break;
+ case '[':
+ $tok = Token::lsquare;
+ break;
+ case ']':
+ $tok = Token::rsquare;
+ break;
+ case ':':
+ $tok = Token::colon;
+ break;
+ case '(':
+ $tok = Token::lparen;
+ break;
+ case ')':
+ $tok = Token::rparen;
+ break;
+ case '+':
+ $tok = Token::plus;
+ break;
+ case '~':
+ $tok = Token::tilde;
+ break;
+ case '=':
+ $tok = Token::eq;
+ break;
+ case '|':
+ $tok = Token::pipe;
+ break;
+ case ',':
+ $tok = Token::comma;
+ break;
+ case chr(34):
+ $tok = Token::quote;
+ break;
+ case "'":
+ $tok = Token::squote;
+ break;
+ case '\\':
+ $tok = Token::bslash;
+ break;
+ case '^':
+ $tok = Token::carat;
+ break;
+ case '$':
+ $tok = Token::dollar;
+ break;
+ case '@':
+ $tok = Token::at;
+ break;
+ }
+
+
+ // Catch all characters that are legal within strings.
+ if ($tok == -1) {
+ // TODO: This should be UTF-8 compatible, but PHP doesn't
+ // have a native UTF-8 string. Should we use external
+ // mbstring library?
+
+ $ord = ord($ch);
+ // Characters in this pool are legal for use inside of
+ // certain strings. Extended ASCII is used here, though I
+ // Don't know if these are really legal.
+ if (($ord >= 32 && $ord <= 126) || ($ord >= 128 && $ord <= 255)) {
+ $tok = Token::stringLegal;
+ }
+ else {
+ throw new ParseException('Illegal character found in stream: ' . $ord);
+ }
+ }
+
+ $this->token = $tok;
+ return $tok;
+ }
+
+ /**
+ * Get a name string from the input stream.
+ * A name string must be composed of
+ * only characters defined in Token:char: -_a-zA-Z0-9
+ */
+ public function getNameString() {
+ $buf = '';
+ while ($this->token === Token::char) {
+ $buf .= $this->value;
+ $this->nextToken();
+ //print '_';
+ }
+ return $buf;
+ }
+
+ /**
+ * This gets a string with any legal 'string' characters.
+ * See CSS Selectors specification, section 11, for the
+ * definition of string.
+ *
+ * This will check for string1, string2, and the case where a
+ * string is unquoted (Oddly absent from the "official" grammar,
+ * though such strings are present as examples in the spec.)
+ *
+ * Note:
+ * Though the grammar supplied by CSS 3 Selectors section 11 does not
+ * address the contents of a pseudo-class value, the spec itself indicates
+ * that a pseudo-class value is a "value between parenthesis" [6.6]. The
+ * examples given use URLs among other things, making them closer to the
+ * definition of 'string' than to 'name'. So we handle them here as strings.
+ */
+ public function getQuotedString() {
+ if ($this->token == Token::quote || $this->token == Token::squote || $this->token == Token::lparen) {
+ $end = ($this->token == Token::lparen) ? Token::rparen : $this->token;
+ $buf = '';
+ $escape = FALSE;
+
+ $this->nextToken(); // Skip the opening quote/paren
+
+ // The second conjunct is probably not necessary.
+ while ($this->token !== FALSE && $this->token > -1) {
+ //print "Char: $this->value \n";
+ if ($this->token == Token::bslash && !$escape) {
+ // XXX: The backslash (\) is removed here.
+ // Turn on escaping.
+ //$buf .= $this->value;
+ $escape = TRUE;
+ }
+ elseif ($escape) {
+ // Turn off escaping
+ $buf .= $this->value;
+ $escape = FALSE;
+ }
+ elseif ($this->token === $end) {
+ // At end of string; skip token and break.
+ $this->nextToken();
+ break;
+ }
+ else {
+ // Append char.
+ $buf .= $this->value;
+ }
+ $this->nextToken();
+ }
+ return $buf;
+ }
+ }
+
+ // Get the contents inside of a pseudoClass().
+ public function getPseudoClassString() {
+ if ($this->token == Token::quote || $this->token == Token::squote || $this->token == Token::lparen) {
+ $end = ($this->token == Token::lparen) ? Token::rparen : $this->token;
+ $buf = '';
+ $escape = FALSE;
+
+ $this->nextToken(); // Skip the opening quote/paren
+
+ // The second conjunct is probably not necessary.
+ while ($this->token !== FALSE && $this->token > -1) {
+ //print "Char: $this->value \n";
+ if ($this->token == Token::bslash && !$escape) {
+ // XXX: The backslash (\) is removed here.
+ // Turn on escaping.
+ //$buf .= $this->value;
+ $escape = TRUE;
+ }
+ elseif ($escape) {
+ // Turn off escaping
+ $buf .= $this->value;
+ $escape = FALSE;
+ }
+ // Allow nested pseudoclasses.
+ elseif ($this->token == Token::lparen) {
+ $buf .= "(";
+ $buf .= $this->getPseudoClassString();
+ $buf .= ")";
+ }
+ elseif ($this->token === $end) {
+ // At end of string; skip token and break.
+ $this->nextToken();
+ break;
+ }
+ else {
+ // Append char.
+ $buf .= $this->value;
+ }
+ $this->nextToken();
+ }
+ return $buf;
+ }
+ }
+
+ /**
+ * Get a string from the input stream.
+ * This is a convenience function for getting a string of
+ * characters that are either alphanumber or whitespace. See
+ * the Token::white and Token::char definitions.
+ *
+ * @deprecated This is not used anywhere in QueryPath.
+ *//*
+ public function getStringPlusWhitespace() {
+ $buf = '';
+ if($this->token === FALSE) {return '';}
+ while ($this->token === Token::char || $this->token == Token::white) {
+ $buf .= $this->value;
+ $this->nextToken();
+ }
+ return $buf;
+ }*/
+
+}
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