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Diffstat (limited to 'src/HTML5/InputStream.php')
-rw-r--r-- | src/HTML5/InputStream.php | 284 |
1 files changed, 284 insertions, 0 deletions
diff --git a/src/HTML5/InputStream.php b/src/HTML5/InputStream.php new file mode 100644 index 0000000..f98b427 --- /dev/null +++ b/src/HTML5/InputStream.php @@ -0,0 +1,284 @@ +<?php + +/* + +Copyright 2009 Geoffrey Sneddon <http://gsnedders.com/> + +Permission is hereby granted, free of charge, to any person obtaining a +copy of this software and associated documentation files (the +"Software"), to deal in the Software without restriction, including +without limitation the rights to use, copy, modify, merge, publish, +distribute, sublicense, and/or sell copies of the Software, and to +permit persons to whom the Software is furnished to do so, subject to +the following conditions: + +The above copyright notice and this permission notice shall be included +in all copies or substantial portions of the Software. + +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS +OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF +MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. +IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY +CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, +TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE +SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + +*/ + +// Some conventions: +// /* */ indicates verbatim text from the HTML 5 specification +// // indicates regular comments + +class HTML5_InputStream { + /** + * The string data we're parsing. + */ + private $data; + + /** + * The current integer byte position we are in $data + */ + private $char; + + /** + * Length of $data; when $char === $data, we are at the end-of-file. + */ + private $EOF; + + /** + * Parse errors. + */ + public $errors = array(); + + /** + * @param $data Data to parse + */ + public function __construct($data) { + + /* Given an encoding, the bytes in the input stream must be + converted to Unicode characters for the tokeniser, as + described by the rules for that encoding, except that the + leading U+FEFF BYTE ORDER MARK character, if any, must not + be stripped by the encoding layer (it is stripped by the rule below). + + Bytes or sequences of bytes in the original byte stream that + could not be converted to Unicode characters must be converted + to U+FFFD REPLACEMENT CHARACTER code points. */ + + // XXX currently assuming input data is UTF-8; once we + // build encoding detection this will no longer be the case + // + // We previously had an mbstring implementation here, but that + // implementation is heavily non-conforming, so it's been + // omitted. + if (extension_loaded('iconv')) { + // non-conforming + $data = @iconv('UTF-8', 'UTF-8//IGNORE', $data); + } else { + // we can make a conforming native implementation + throw new Exception('Not implemented, please install mbstring or iconv'); + } + + /* One leading U+FEFF BYTE ORDER MARK character must be + ignored if any are present. */ + if (substr($data, 0, 3) === "\xEF\xBB\xBF") { + $data = substr($data, 3); + } + + /* All U+0000 NULL characters in the input must be replaced + by U+FFFD REPLACEMENT CHARACTERs. Any occurrences of such + characters is a parse error. */ + for ($i = 0, $count = substr_count($data, "\0"); $i < $count; $i++) { + $this->errors[] = array( + 'type' => HTML5_Tokenizer::PARSEERROR, + 'data' => 'null-character' + ); + } + /* U+000D CARRIAGE RETURN (CR) characters and U+000A LINE FEED + (LF) characters are treated specially. Any CR characters + that are followed by LF characters must be removed, and any + CR characters not followed by LF characters must be converted + to LF characters. Thus, newlines in HTML DOMs are represented + by LF characters, and there are never any CR characters in the + input to the tokenization stage. */ + $data = str_replace( + array( + "\0", + "\r\n", + "\r" + ), + array( + "\xEF\xBF\xBD", + "\n", + "\n" + ), + $data + ); + + /* Any occurrences of any characters in the ranges U+0001 to + U+0008, U+000B, U+000E to U+001F, U+007F to U+009F, + U+D800 to U+DFFF , U+FDD0 to U+FDEF, and + characters U+FFFE, U+FFFF, U+1FFFE, U+1FFFF, U+2FFFE, U+2FFFF, + U+3FFFE, U+3FFFF, U+4FFFE, U+4FFFF, U+5FFFE, U+5FFFF, U+6FFFE, + U+6FFFF, U+7FFFE, U+7FFFF, U+8FFFE, U+8FFFF, U+9FFFE, U+9FFFF, + U+AFFFE, U+AFFFF, U+BFFFE, U+BFFFF, U+CFFFE, U+CFFFF, U+DFFFE, + U+DFFFF, U+EFFFE, U+EFFFF, U+FFFFE, U+FFFFF, U+10FFFE, and + U+10FFFF are parse errors. (These are all control characters + or permanently undefined Unicode characters.) */ + // Check PCRE is loaded. + if (extension_loaded('pcre')) { + $count = preg_match_all( + '/(?: + [\x01-\x08\x0B\x0E-\x1F\x7F] # U+0001 to U+0008, U+000B, U+000E to U+001F and U+007F + | + \xC2[\x80-\x9F] # U+0080 to U+009F + | + \xED(?:\xA0[\x80-\xFF]|[\xA1-\xBE][\x00-\xFF]|\xBF[\x00-\xBF]) # U+D800 to U+DFFFF + | + \xEF\xB7[\x90-\xAF] # U+FDD0 to U+FDEF + | + \xEF\xBF[\xBE\xBF] # U+FFFE and U+FFFF + | + [\xF0-\xF4][\x8F-\xBF]\xBF[\xBE\xBF] # U+nFFFE and U+nFFFF (1 <= n <= 10_{16}) + )/x', + $data, + $matches + ); + for ($i = 0; $i < $count; $i++) { + $this->errors[] = array( + 'type' => HTML5_Tokenizer::PARSEERROR, + 'data' => 'invalid-codepoint' + ); + } + } else { + // XXX: Need non-PCRE impl, probably using substr_count + } + + $this->data = $data; + $this->char = 0; + $this->EOF = strlen($data); + } + + /** + * Returns the current line that the tokenizer is at. + */ + public function getCurrentLine() { + // Check the string isn't empty + if($this->EOF) { + // Add one to $this->char because we want the number for the next + // byte to be processed. + return substr_count($this->data, "\n", 0, min($this->char, $this->EOF)) + 1; + } else { + // If the string is empty, we are on the first line (sorta). + return 1; + } + } + + /** + * Returns the current column of the current line that the tokenizer is at. + */ + public function getColumnOffset() { + // strrpos is weird, and the offset needs to be negative for what we + // want (i.e., the last \n before $this->char). This needs to not have + // one (to make it point to the next character, the one we want the + // position of) added to it because strrpos's behaviour includes the + // final offset byte. + $lastLine = strrpos($this->data, "\n", $this->char - 1 - strlen($this->data)); + + // However, for here we want the length up until the next byte to be + // processed, so add one to the current byte ($this->char). + if($lastLine !== false) { + $findLengthOf = substr($this->data, $lastLine + 1, $this->char - 1 - $lastLine); + } else { + $findLengthOf = substr($this->data, 0, $this->char); + } + + // Get the length for the string we need. + if(extension_loaded('iconv')) { + return iconv_strlen($findLengthOf, 'utf-8'); + } elseif(extension_loaded('mbstring')) { + return mb_strlen($findLengthOf, 'utf-8'); + } elseif(extension_loaded('xml')) { + return strlen(utf8_decode($findLengthOf)); + } else { + $count = count_chars($findLengthOf); + // 0x80 = 0x7F - 0 + 1 (one added to get inclusive range) + // 0x33 = 0xF4 - 0x2C + 1 (one added to get inclusive range) + return array_sum(array_slice($count, 0, 0x80)) + + array_sum(array_slice($count, 0xC2, 0x33)); + } + } + + /** + * Retrieve the currently consume character. + * @note This performs bounds checking + */ + public function char() { + return ($this->char++ < $this->EOF) + ? $this->data[$this->char - 1] + : false; + } + + /** + * Get all characters until EOF. + * @note This performs bounds checking + */ + public function remainingChars() { + if($this->char < $this->EOF) { + $data = substr($this->data, $this->char); + $this->char = $this->EOF; + return $data; + } else { + return false; + } + } + + /** + * Matches as far as possible until we reach a certain set of bytes + * and returns the matched substring. + * @param $bytes Bytes to match. + */ + public function charsUntil($bytes, $max = null) { + if ($this->char < $this->EOF) { + if ($max === 0 || $max) { + $len = strcspn($this->data, $bytes, $this->char, $max); + } else { + $len = strcspn($this->data, $bytes, $this->char); + } + $string = (string) substr($this->data, $this->char, $len); + $this->char += $len; + return $string; + } else { + return false; + } + } + + /** + * Matches as far as possible with a certain set of bytes + * and returns the matched substring. + * @param $bytes Bytes to match. + */ + public function charsWhile($bytes, $max = null) { + if ($this->char < $this->EOF) { + if ($max === 0 || $max) { + $len = strspn($this->data, $bytes, $this->char, $max); + } else { + $len = strspn($this->data, $bytes, $this->char); + } + $string = (string) substr($this->data, $this->char, $len); + $this->char += $len; + return $string; + } else { + return false; + } + } + + /** + * Unconsume one character. + */ + public function unget() { + if ($this->char <= $this->EOF) { + $this->char--; + } + } +} |