www.aleph1.co.uk Git - yaffs-website/blob - vendor/symfony/var-dumper/Cloner/VarCloner.php

   1 <?php
   2
   3 /*
   4  * This file is part of the Symfony package.
   5  *
   6  * (c) Fabien Potencier <fabien@symfony.com>
   7  *
   8  * For the full copyright and license information, please view the LICENSE
   9  * file that was distributed with this source code.
  10  */
  11
  12 namespace Symfony\Component\VarDumper\Cloner;
  13
  14 /**
  15  * @author Nicolas Grekas <p@tchwork.com>
  16  */
  17 class VarCloner extends AbstractCloner
  18 {
  19     private static $gid;
  20     private static $hashMask = 0;
  21     private static $hashOffset = 0;
  22     private static $arrayCache = array();
  23
  24     /**
  25      * {@inheritdoc}
  26      */
  27     protected function doClone($var)
  28     {
  29         $len = 1;                       // Length of $queue
  30         $pos = 0;                       // Number of cloned items past the minimum depth
  31         $refsCounter = 0;               // Hard references counter
  32         $queue = array(array($var));    // This breadth-first queue is the return value
  33         $indexedArrays = array();       // Map of queue indexes that hold numerically indexed arrays
  34         $hardRefs = array();            // Map of original zval hashes to stub objects
  35         $objRefs = array();             // Map of original object handles to their stub object couterpart
  36         $resRefs = array();             // Map of original resource handles to their stub object couterpart
  37         $values = array();              // Map of stub objects' hashes to original values
  38         $maxItems = $this->maxItems;
  39         $maxString = $this->maxString;
  40         $minDepth = $this->minDepth;
  41         $currentDepth = 0;              // Current tree depth
  42         $currentDepthFinalIndex = 0;    // Final $queue index for current tree depth
  43         $minimumDepthReached = 0 === $minDepth; // Becomes true when minimum tree depth has been reached
  44         $cookie = (object) array();     // Unique object used to detect hard references
  45         $a = null;                      // Array cast for nested structures
  46         $stub = null;                   // Stub capturing the main properties of an original item value
  47                                         // or null if the original value is used directly
  48
  49         if (!self::$hashMask) {
  50             self::$gid = uniqid(mt_rand(), true); // Unique string used to detect the special $GLOBALS variable
  51             self::initHashMask();
  52         }
  53         $gid = self::$gid;
  54         $hashMask = self::$hashMask;
  55         $hashOffset = self::$hashOffset;
  56         $arrayStub = new Stub();
  57         $arrayStub->type = Stub::TYPE_ARRAY;
  58         $fromObjCast = false;
  59
  60         for ($i = 0; $i < $len; ++$i) {
  61             // Detect when we move on to the next tree depth
  62             if ($i > $currentDepthFinalIndex) {
  63                 ++$currentDepth;
  64                 $currentDepthFinalIndex = $len - 1;
  65                 if ($currentDepth >= $minDepth) {
  66                     $minimumDepthReached = true;
  67                 }
  68             }
  69
  70             $refs = $vals = $queue[$i];
  71             if (\PHP_VERSION_ID < 70200 && empty($indexedArrays[$i])) {
  72                 // see https://wiki.php.net/rfc/convert_numeric_keys_in_object_array_casts
  73                 foreach ($vals as $k => $v) {
  74                     if (\is_int($k)) {
  75                         continue;
  76                     }
  77                     foreach (array($k => true) as $gk => $gv) {
  78                     }
  79                     if ($gk !== $k) {
  80                         $fromObjCast = true;
  81                         $refs = $vals = \array_values($queue[$i]);
  82                         break;
  83                     }
  84                 }
  85             }
  86             foreach ($vals as $k => $v) {
  87                 // $v is the original value or a stub object in case of hard references
  88                 $refs[$k] = $cookie;
  89                 if ($zvalIsRef = $vals[$k] === $cookie) {
  90                     $vals[$k] = &$stub;         // Break hard references to make $queue completely
  91                     unset($stub);               // independent from the original structure
  92                     if ($v instanceof Stub && isset($hardRefs[\spl_object_hash($v)])) {
  93                         $vals[$k] = $refs[$k] = $v;
  94                         if ($v->value instanceof Stub && (Stub::TYPE_OBJECT === $v->value->type || Stub::TYPE_RESOURCE === $v->value->type)) {
  95                             ++$v->value->refCount;
  96                         }
  97                         ++$v->refCount;
  98                         continue;
  99                     }
 100                     $refs[$k] = $vals[$k] = new Stub();
 101                     $refs[$k]->value = $v;
 102                     $h = \spl_object_hash($refs[$k]);
 103                     $hardRefs[$h] = &$refs[$k];
 104                     $values[$h] = $v;
 105                     $vals[$k]->handle = ++$refsCounter;
 106                 }
 107                 // Create $stub when the original value $v can not be used directly
 108                 // If $v is a nested structure, put that structure in array $a
 109                 switch (true) {
 110                     case null === $v:
 111                     case \is_bool($v):
 112                     case \is_int($v):
 113                     case \is_float($v):
 114                         continue 2;
 115
 116                     case \is_string($v):
 117                         if ('' === $v) {
 118                             continue 2;
 119                         }
 120                         if (!\preg_match('//u', $v)) {
 121                             $stub = new Stub();
 122                             $stub->type = Stub::TYPE_STRING;
 123                             $stub->class = Stub::STRING_BINARY;
 124                             if (0 <= $maxString && 0 < $cut = \strlen($v) - $maxString) {
 125                                 $stub->cut = $cut;
 126                                 $stub->value = \substr($v, 0, -$cut);
 127                             } else {
 128                                 $stub->value = $v;
 129                             }
 130                         } elseif (0 <= $maxString && isset($v[1 + ($maxString >> 2)]) && 0 < $cut = \mb_strlen($v, 'UTF-8') - $maxString) {
 131                             $stub = new Stub();
 132                             $stub->type = Stub::TYPE_STRING;
 133                             $stub->class = Stub::STRING_UTF8;
 134                             $stub->cut = $cut;
 135                             $stub->value = \mb_substr($v, 0, $maxString, 'UTF-8');
 136                         } else {
 137                             continue 2;
 138                         }
 139                         $a = null;
 140                         break;
 141
 142                     case \is_array($v):
 143                         if (!$v) {
 144                             continue 2;
 145                         }
 146                         $stub = $arrayStub;
 147                         $stub->class = Stub::ARRAY_INDEXED;
 148
 149                         $j = -1;
 150                         foreach ($v as $gk => $gv) {
 151                             if ($gk !== ++$j) {
 152                                 $stub->class = Stub::ARRAY_ASSOC;
 153                                 break;
 154                             }
 155                         }
 156                         $a = $v;
 157
 158                         if (Stub::ARRAY_ASSOC === $stub->class) {
 159                             // Copies of $GLOBALS have very strange behavior,
 160                             // let's detect them with some black magic
 161                             $a[$gid] = true;
 162
 163                             // Happens with copies of $GLOBALS
 164                             if (isset($v[$gid])) {
 165                                 unset($v[$gid]);
 166                                 $a = array();
 167                                 foreach ($v as $gk => &$gv) {
 168                                     $a[$gk] = &$gv;
 169                                 }
 170                                 unset($gv);
 171                             } else {
 172                                 $a = $v;
 173                             }
 174                         } elseif (\PHP_VERSION_ID < 70200) {
 175                             $indexedArrays[$len] = true;
 176                         }
 177                         break;
 178
 179                     case \is_object($v):
 180                     case $v instanceof \__PHP_Incomplete_Class:
 181                         if (empty($objRefs[$h = $hashMask ^ \hexdec(\substr(\spl_object_hash($v), $hashOffset, \PHP_INT_SIZE))])) {
 182                             $stub = new Stub();
 183                             $stub->type = Stub::TYPE_OBJECT;
 184                             $stub->class = \get_class($v);
 185                             $stub->value = $v;
 186                             $stub->handle = $h;
 187                             $a = $this->castObject($stub, 0 < $i);
 188                             if ($v !== $stub->value) {
 189                                 if (Stub::TYPE_OBJECT !== $stub->type || null === $stub->value) {
 190                                     break;
 191                                 }
 192                                 $h = $hashMask ^ \hexdec(\substr(\spl_object_hash($stub->value), $hashOffset, \PHP_INT_SIZE));
 193                                 $stub->handle = $h;
 194                             }
 195                             $stub->value = null;
 196                             if (0 <= $maxItems && $maxItems <= $pos && $minimumDepthReached) {
 197                                 $stub->cut = \count($a);
 198                                 $a = null;
 199                             }
 200                         }
 201                         if (empty($objRefs[$h])) {
 202                             $objRefs[$h] = $stub;
 203                         } else {
 204                             $stub = $objRefs[$h];
 205                             ++$stub->refCount;
 206                             $a = null;
 207                         }
 208                         break;
 209
 210                     default: // resource
 211                         if (empty($resRefs[$h = (int) $v])) {
 212                             $stub = new Stub();
 213                             $stub->type = Stub::TYPE_RESOURCE;
 214                             if ('Unknown' === $stub->class = @\get_resource_type($v)) {
 215                                 $stub->class = 'Closed';
 216                             }
 217                             $stub->value = $v;
 218                             $stub->handle = $h;
 219                             $a = $this->castResource($stub, 0 < $i);
 220                             $stub->value = null;
 221                             if (0 <= $maxItems && $maxItems <= $pos && $minimumDepthReached) {
 222                                 $stub->cut = \count($a);
 223                                 $a = null;
 224                             }
 225                         }
 226                         if (empty($resRefs[$h])) {
 227                             $resRefs[$h] = $stub;
 228                         } else {
 229                             $stub = $resRefs[$h];
 230                             ++$stub->refCount;
 231                             $a = null;
 232                         }
 233                         break;
 234                 }
 235
 236                 if ($a) {
 237                     if (!$minimumDepthReached || 0 > $maxItems) {
 238                         $queue[$len] = $a;
 239                         $stub->position = $len++;
 240                     } elseif ($pos < $maxItems) {
 241                         if ($maxItems < $pos += \count($a)) {
 242                             $a = \array_slice($a, 0, $maxItems - $pos);
 243                             if ($stub->cut >= 0) {
 244                                 $stub->cut += $pos - $maxItems;
 245                             }
 246                         }
 247                         $queue[$len] = $a;
 248                         $stub->position = $len++;
 249                     } elseif ($stub->cut >= 0) {
 250                         $stub->cut += \count($a);
 251                         $stub->position = 0;
 252                     }
 253                 }
 254
 255                 if ($arrayStub === $stub) {
 256                     if ($arrayStub->cut) {
 257                         $stub = array($arrayStub->cut, $arrayStub->class => $arrayStub->position);
 258                         $arrayStub->cut = 0;
 259                     } elseif (isset(self::$arrayCache[$arrayStub->class][$arrayStub->position])) {
 260                         $stub = self::$arrayCache[$arrayStub->class][$arrayStub->position];
 261                     } else {
 262                         self::$arrayCache[$arrayStub->class][$arrayStub->position] = $stub = array($arrayStub->class => $arrayStub->position);
 263                     }
 264                 }
 265
 266                 if ($zvalIsRef) {
 267                     $refs[$k]->value = $stub;
 268                 } else {
 269                     $vals[$k] = $stub;
 270                 }
 271             }
 272
 273             if ($fromObjCast) {
 274                 $fromObjCast = false;
 275                 $refs = $vals;
 276                 $vals = array();
 277                 $j = -1;
 278                 foreach ($queue[$i] as $k => $v) {
 279                     foreach (array($k => true) as $gk => $gv) {
 280                     }
 281                     if ($gk !== $k) {
 282                         $vals = (object) $vals;
 283                         $vals->{$k} = $refs[++$j];
 284                         $vals = (array) $vals;
 285                     } else {
 286                         $vals[$k] = $refs[++$j];
 287                     }
 288                 }
 289             }
 290
 291             $queue[$i] = $vals;
 292         }
 293
 294         foreach ($values as $h => $v) {
 295             $hardRefs[$h] = $v;
 296         }
 297
 298         return $queue;
 299     }
 300
 301     private static function initHashMask()
 302     {
 303         $obj = (object) array();
 304         self::$hashOffset = 16 - PHP_INT_SIZE;
 305         self::$hashMask = -1;
 306
 307         if (defined('HHVM_VERSION')) {
 308             self::$hashOffset += 16;
 309         } else {
 310             // check if we are nested in an output buffering handler to prevent a fatal error with ob_start() below
 311             $obFuncs = array('ob_clean', 'ob_end_clean', 'ob_flush', 'ob_end_flush', 'ob_get_contents', 'ob_get_flush');
 312             foreach (debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS) as $frame) {
 313                 if (isset($frame['function'][0]) && !isset($frame['class']) && 'o' === $frame['function'][0] && in_array($frame['function'], $obFuncs)) {
 314                     $frame['line'] = 0;
 315                     break;
 316                 }
 317             }
 318             if (!empty($frame['line'])) {
 319                 ob_start();
 320                 debug_zval_dump($obj);
 321                 self::$hashMask = (int) substr(ob_get_clean(), 17);
 322             }
 323         }
 324
 325         self::$hashMask ^= hexdec(substr(spl_object_hash($obj), self::$hashOffset, PHP_INT_SIZE));
 326     }
 327 }