API tools faq
paste
Pr4w

NBT Parser

Pr4w
Aug 24th, 2011
367
0
Never
Add comment
Not a member of Pastebin yet? Sign Up, it unlocks many cool features!
PHP 7.51 KB | None | 0 0
raw download clone embed print report
  1. <?php
  2. /**
  3.  * Class for reading in NBT-format files.
  4.  * Based on the work of Justin Martin <frozenfire@thefrozenfire.com>.
  5.  * Altered to use BCMath rather than GMP, because BCMath comes by default with PHP >= 4.0.4, GMP never did.
  6.  *
  7.  * @author  Julian Rupp <mail@nuclearflux.net>
  8.  * @version 1.1
  9.  *
  10.  * Dependencies:
  11.  *  PHP 4.3+ (5.3+ recommended)
  12.  *  BCMath Extension
  13.  */
  14.  
  15. extension_loaded("bcmath") or die("The NBT class requires the BCMath extension.");
  16. class NBT {
  17.     public $root = array();
  18.    
  19.     public $verbose = false;
  20.    
  21.     const TAG_END = 0;
  22.     const TAG_BYTE = 1;
  23.     const TAG_SHORT = 2;
  24.     const TAG_INT = 3;
  25.     const TAG_LONG = 4;
  26.     const TAG_FLOAT = 5;
  27.     const TAG_DOUBLE = 6;
  28.     const TAG_BYTE_ARRAY = 7;
  29.     const TAG_STRING = 8;
  30.     const TAG_LIST = 9;
  31.     const TAG_COMPOUND = 10;
  32.    
  33.     public function loadFile($filename) {
  34.         $fp = fopen("compress.zlib://{$filename}", "rb");
  35.         $this->traverseTag($fp, $this->root);
  36.         return end($this->root);
  37.     }
  38.    
  39.     public function writeFile($filename) {
  40.         $fp = fopen("compress.zlib://{$filename}", "wb");
  41.         foreach($this->root as $rootTag) if(!$this->writeTag($fp, $rootTag)) return false;
  42.         return true;
  43.     }
  44.    
  45.     public function purge() {
  46.         $this->root = array();
  47.     }
  48.    
  49.     protected function _signedlong2intstring($bin)
  50.     {
  51.         if(strlen($bin) != 8)
  52.         {
  53.             return(false);
  54.         }
  55.         list(,$firstHalf) = unpack("N", substr($bin,0,4));
  56.         list(,$secondHalf) = unpack("N", substr($bin,4,4));
  57.         $value = bcadd($secondHalf, bcmul($firstHalf, "4294967296"));
  58.         if(bccomp($value, bcpow(2, 63)) >= 0) $value = bcsub($value, bcpow(2, 64));
  59.         return($value);
  60.     }
  61.    
  62.     protected function _intstring2signedlong($string)
  63.     {
  64.         #todo: input check
  65.  
  66.         $sbt = array();
  67.         $sby = array();
  68.         $ret = '';
  69.         $c_remaining = $string;
  70.         $c_mod = 0;
  71.  
  72.         for($i=0;$i<64;$i++)
  73.         {
  74.             $sbt[$i] = 0;
  75.         }
  76.  
  77.         for($mp=63,$i=0;$mp>=0,$i<64;$mp--,$i++)
  78.         {
  79.             $c_mod = bcdiv($c_remaining,bcpow(2,$mp));
  80.             $c_remaining = bcmod($c_remaining,bcpow(2,$mp));
  81.             if(bccomp($c_mod,"1") >= 0)
  82.             {
  83.                 $sbt[$i] = 1;
  84.             }
  85.  
  86.             if(bccomp($c_remaining,"0") == 0)
  87.             {
  88.                 break;
  89.             }
  90.         }
  91.  
  92.         for($i=0;$i<8;$i++)
  93.         {
  94.             $bin = '';
  95.             for($j=0;$j<8;$j++)
  96.             {
  97.                 $os = ($i*8)+$j;
  98.                 $bin .= $sbt[$os];
  99.             }
  100.             $sby[$i] = chr(bindec($bin));
  101.         }
  102.         $ret = implode($sby);
  103.         if(bccomp($ret, bcpow(2, 63)) >= 0)
  104.         {
  105.             $ret = bcsub($ret, bcpow(2, 64));
  106.         }
  107.  
  108.         return($ret);
  109.     }
  110.    
  111.     protected function traverseTag($fp, &$tree) {
  112.         if(feof($fp)) return false;
  113.         $tagType = $this->readType($fp, self::TAG_BYTE); // Read type byte.
  114.         if($tagType == self::TAG_END) {
  115.             return false;
  116.         } else {
  117.             if($this->verbose) $position = ftell($fp);
  118.             $tagName = $this->readType($fp, self::TAG_STRING);
  119.             $tagData = $this->readType($fp, $tagType);
  120.             if($this->verbose) echo "Reading tag \"{$tagName}\" at offset {$position}".PHP_EOL;
  121.             $tree[] = array("type"=>$tagType, "name"=>$tagName, "value"=>$tagData);
  122.             return true;
  123.         }
  124.     }
  125.    
  126.     protected function writeTag($fp, $tag) {
  127.         if($this->verbose) echo "Writing tag \"{$tag["name"]}\" of type {$tag["type"]}".PHP_EOL;
  128.         return $this->writeType($fp, self::TAG_BYTE, $tag["type"]) && $this->writeType($fp, self::TAG_STRING, $tag["name"]) && $this->writeType($fp, $tag["type"], $tag["value"]);
  129.     }
  130.    
  131.     protected function readType($fp, $tagType) {
  132.         switch($tagType) {
  133.             case self::TAG_BYTE: // Signed byte (8 bit)
  134.                 list(,$unpacked) = unpack("c", fread($fp, 1));
  135.                 return $unpacked;
  136.             case self::TAG_SHORT: // Signed short (16 bit, big endian)
  137.                 list(,$unpacked) = unpack("n", fread($fp, 2));
  138.                 if($unpacked >= pow(2, 15)) $unpacked -= pow(2, 16); // Convert unsigned short to signed short.
  139.                 return $unpacked;
  140.             case self::TAG_INT: // Signed integer (32 bit, big endian)
  141.                 list(,$unpacked) = unpack("N", fread($fp, 4));
  142.                 if($unpacked >= pow(2, 31)) $unpacked -= pow(2, 32); // Convert unsigned int to signed int
  143.                 return $unpacked;
  144.             case self::TAG_LONG: // Signed long (64 bit, big endian)
  145.                 return($this->_signedlong2intstring(fread($fp, 8)));
  146.             case self::TAG_FLOAT: // Floating point value (32 bit, big endian, IEEE 754-2008)
  147.                 list(,$value) = (pack('d', 1) == "\77\360\0\0\0\0\0\0")?unpack('f', fread($fp, 4)):unpack('f', strrev(fread($fp, 4)));
  148.                 return $value;
  149.             case self::TAG_DOUBLE: // Double value (64 bit, big endian, IEEE 754-2008)
  150.                 list(,$value) = (pack('d', 1) == "\77\360\0\0\0\0\0\0")?unpack('d', fread($fp, 8)):unpack('d', strrev(fread($fp, 8)));
  151.                 return $value;
  152.             case self::TAG_BYTE_ARRAY: // Byte array
  153.                 $arrayLength = $this->readType($fp, self::TAG_INT);
  154.                 $array = array();
  155.                 for($i = 0; $i < $arrayLength; $i++) $array[] = $this->readType($fp, self::TAG_BYTE);
  156.                 return $array;
  157.             case self::TAG_STRING: // String
  158.                 if(!$stringLength = $this->readType($fp, self::TAG_SHORT)) return "";
  159.                 $string = utf8_decode(fread($fp, $stringLength)); // Read in number of bytes specified by string length, and decode from utf8.
  160.                 return $string;
  161.             case self::TAG_LIST: // List
  162.                 $tagID = $this->readType($fp, self::TAG_BYTE);
  163.                 $listLength = $this->readType($fp, self::TAG_INT);
  164.                 if($this->verbose) echo "Reading in list of {$listLength} tags of type {$tagID}.".PHP_EOL;
  165.                 $list = array("type"=>$tagID, "value"=>array());
  166.                 for($i = 0; $i < $listLength; $i++) {
  167.                     if(feof($fp)) break;
  168.                     $list["value"][] = $this->readType($fp, $tagID);
  169.                 }
  170.                 return $list;
  171.             case self::TAG_COMPOUND: // Compound
  172.                 $tree = array();
  173.                 while($this->traverseTag($fp, $tree));
  174.                 return $tree;
  175.         }
  176.     }
  177.    
  178.     protected function writeType($fp, $tagType, $value) {
  179.         switch($tagType) {
  180.             case self::TAG_BYTE: // Signed byte (8 bit)
  181.                 return fwrite($fp, pack("c", $value));
  182.             case self::TAG_SHORT: // Signed short (16 bit, big endian)
  183.                 if($value < 0) $value += pow(2, 16); // Convert signed short to unsigned short
  184.                 return fwrite($fp, pack("n", $value));
  185.             case self::TAG_INT: // Signed integer (32 bit, big endian)
  186.                 if($value < 0) $value += pow(2, 32); // Convert signed int to unsigned int
  187.                 return fwrite($fp, pack("N", $value));
  188.             case self::TAG_LONG: // Signed long (64 bit, big endian)
  189.                 $data = $this->_intstring2signedlong($value);
  190.                 return fwrite($fp, $data);
  191.             case self::TAG_FLOAT: // Floating point value (32 bit, big endian, IEEE 754-2008)
  192.                 return fwrite($fp, (pack('d', 1) == "\77\360\0\0\0\0\0\0")?pack('f', $value):strrev(pack('f', $value)));
  193.             case self::TAG_DOUBLE: // Double value (64 bit, big endian, IEEE 754-2008)
  194.                 return fwrite($fp, (pack('d', 1) == "\77\360\0\0\0\0\0\0")?pack('d', $value):strrev(pack('d', $value)));
  195.             case self::TAG_BYTE_ARRAY: // Byte array
  196.                 return $this->writeType($fp, self::TAG_INT, count($value)) && fwrite($fp, call_user_func_array("pack", array_merge(array("c".count($value)), $value)));
  197.             case self::TAG_STRING: // String
  198.                 $value = utf8_encode($value);
  199.                 return $this->writeType($fp, self::TAG_SHORT, strlen($value)) && fwrite($fp, $value);
  200.             case self::TAG_LIST: // List
  201.                 if($this->verbose) echo "Writing list of ".count($value["value"])." tags of type {$value["type"]}.".PHP_EOL;
  202.                 if(!($this->writeType($fp, self::TAG_BYTE, $value["type"]) && $this->writeType($fp, self::TAG_INT, count($value["value"])))) return false;
  203.                 foreach($value["value"] as $listItem) if(!$this->writeType($fp, $value["type"], $listItem)) return false;
  204.                 return true;
  205.             case self::TAG_COMPOUND: // Compound
  206.                 foreach($value as $listItem) if(!$this->writeTag($fp, $listItem)) return false;
  207.                 if(!fwrite($fp, "\0")) return false;
  208.                 return true;
  209.         }
  210.     }
  211. }
  212. ?>
Add Comment
Please, Sign In to add comment
Public Pastes
We use cookies for various purposes including analytics. By continuing to use Pastebin, you agree to our use of cookies as described in the Cookies Policy.  OK, I Understand
Not a member of Pastebin yet?
Sign Up, it unlocks many cool features!