Chris@0: <?php
Chris@0: 
Chris@0: /*
Chris@0:  * This file is part of the Symfony package.
Chris@0:  *
Chris@0:  * (c) Fabien Potencier <fabien@symfony.com>
Chris@0:  *
Chris@0:  * For the full copyright and license information, please view the LICENSE
Chris@0:  * file that was distributed with this source code.
Chris@0:  */
Chris@0: 
Chris@0: namespace Symfony\Component\VarDumper\Cloner;
Chris@0: 
Chris@0: /**
Chris@0:  * @author Nicolas Grekas <p@tchwork.com>
Chris@0:  */
Chris@0: class VarCloner extends AbstractCloner
Chris@0: {
Chris@0:     private static $gid;
Chris@0:     private static $hashMask = 0;
Chris@0:     private static $hashOffset = 0;
Chris@17:     private static $arrayCache = [];
Chris@0: 
Chris@0:     /**
Chris@0:      * {@inheritdoc}
Chris@0:      */
Chris@0:     protected function doClone($var)
Chris@0:     {
Chris@0:         $len = 1;                       // Length of $queue
Chris@12:         $pos = 0;                       // Number of cloned items past the minimum depth
Chris@0:         $refsCounter = 0;               // Hard references counter
Chris@17:         $queue = [[$var]];    // This breadth-first queue is the return value
Chris@17:         $indexedArrays = [];       // Map of queue indexes that hold numerically indexed arrays
Chris@17:         $hardRefs = [];            // Map of original zval hashes to stub objects
Chris@17:         $objRefs = [];             // Map of original object handles to their stub object counterpart
Chris@18:         $objects = [];             // Keep a ref to objects to ensure their handle cannot be reused while cloning
Chris@17:         $resRefs = [];             // Map of original resource handles to their stub object counterpart
Chris@17:         $values = [];              // Map of stub objects' hashes to original values
Chris@0:         $maxItems = $this->maxItems;
Chris@0:         $maxString = $this->maxString;
Chris@12:         $minDepth = $this->minDepth;
Chris@12:         $currentDepth = 0;              // Current tree depth
Chris@12:         $currentDepthFinalIndex = 0;    // Final $queue index for current tree depth
Chris@12:         $minimumDepthReached = 0 === $minDepth; // Becomes true when minimum tree depth has been reached
Chris@17:         $cookie = (object) [];     // Unique object used to detect hard references
Chris@0:         $a = null;                      // Array cast for nested structures
Chris@0:         $stub = null;                   // Stub capturing the main properties of an original item value
Chris@0:                                         // or null if the original value is used directly
Chris@0: 
Chris@0:         if (!self::$hashMask) {
Chris@0:             self::$gid = uniqid(mt_rand(), true); // Unique string used to detect the special $GLOBALS variable
Chris@0:             self::initHashMask();
Chris@0:         }
Chris@0:         $gid = self::$gid;
Chris@0:         $hashMask = self::$hashMask;
Chris@0:         $hashOffset = self::$hashOffset;
Chris@0:         $arrayStub = new Stub();
Chris@0:         $arrayStub->type = Stub::TYPE_ARRAY;
Chris@0:         $fromObjCast = false;
Chris@0: 
Chris@0:         for ($i = 0; $i < $len; ++$i) {
Chris@12:             // Detect when we move on to the next tree depth
Chris@12:             if ($i > $currentDepthFinalIndex) {
Chris@12:                 ++$currentDepth;
Chris@12:                 $currentDepthFinalIndex = $len - 1;
Chris@12:                 if ($currentDepth >= $minDepth) {
Chris@12:                     $minimumDepthReached = true;
Chris@12:                 }
Chris@12:             }
Chris@12: 
Chris@0:             $refs = $vals = $queue[$i];
Chris@0:             if (\PHP_VERSION_ID < 70200 && empty($indexedArrays[$i])) {
Chris@0:                 // see https://wiki.php.net/rfc/convert_numeric_keys_in_object_array_casts
Chris@0:                 foreach ($vals as $k => $v) {
Chris@0:                     if (\is_int($k)) {
Chris@0:                         continue;
Chris@0:                     }
Chris@17:                     foreach ([$k => true] as $gk => $gv) {
Chris@0:                     }
Chris@0:                     if ($gk !== $k) {
Chris@0:                         $fromObjCast = true;
Chris@0:                         $refs = $vals = \array_values($queue[$i]);
Chris@0:                         break;
Chris@0:                     }
Chris@0:                 }
Chris@0:             }
Chris@0:             foreach ($vals as $k => $v) {
Chris@0:                 // $v is the original value or a stub object in case of hard references
Chris@0:                 $refs[$k] = $cookie;
Chris@0:                 if ($zvalIsRef = $vals[$k] === $cookie) {
Chris@0:                     $vals[$k] = &$stub;         // Break hard references to make $queue completely
Chris@0:                     unset($stub);               // independent from the original structure
Chris@0:                     if ($v instanceof Stub && isset($hardRefs[\spl_object_hash($v)])) {
Chris@0:                         $vals[$k] = $refs[$k] = $v;
Chris@0:                         if ($v->value instanceof Stub && (Stub::TYPE_OBJECT === $v->value->type || Stub::TYPE_RESOURCE === $v->value->type)) {
Chris@0:                             ++$v->value->refCount;
Chris@0:                         }
Chris@0:                         ++$v->refCount;
Chris@0:                         continue;
Chris@0:                     }
Chris@0:                     $refs[$k] = $vals[$k] = new Stub();
Chris@0:                     $refs[$k]->value = $v;
Chris@0:                     $h = \spl_object_hash($refs[$k]);
Chris@0:                     $hardRefs[$h] = &$refs[$k];
Chris@0:                     $values[$h] = $v;
Chris@0:                     $vals[$k]->handle = ++$refsCounter;
Chris@0:                 }
Chris@0:                 // Create $stub when the original value $v can not be used directly
Chris@0:                 // If $v is a nested structure, put that structure in array $a
Chris@0:                 switch (true) {
Chris@12:                     case null === $v:
Chris@12:                     case \is_bool($v):
Chris@0:                     case \is_int($v):
Chris@0:                     case \is_float($v):
Chris@0:                         continue 2;
Chris@0: 
Chris@0:                     case \is_string($v):
Chris@12:                         if ('' === $v) {
Chris@12:                             continue 2;
Chris@12:                         }
Chris@0:                         if (!\preg_match('//u', $v)) {
Chris@0:                             $stub = new Stub();
Chris@0:                             $stub->type = Stub::TYPE_STRING;
Chris@0:                             $stub->class = Stub::STRING_BINARY;
Chris@0:                             if (0 <= $maxString && 0 < $cut = \strlen($v) - $maxString) {
Chris@0:                                 $stub->cut = $cut;
Chris@0:                                 $stub->value = \substr($v, 0, -$cut);
Chris@0:                             } else {
Chris@0:                                 $stub->value = $v;
Chris@0:                             }
Chris@0:                         } elseif (0 <= $maxString && isset($v[1 + ($maxString >> 2)]) && 0 < $cut = \mb_strlen($v, 'UTF-8') - $maxString) {
Chris@0:                             $stub = new Stub();
Chris@0:                             $stub->type = Stub::TYPE_STRING;
Chris@0:                             $stub->class = Stub::STRING_UTF8;
Chris@0:                             $stub->cut = $cut;
Chris@0:                             $stub->value = \mb_substr($v, 0, $maxString, 'UTF-8');
Chris@0:                         } else {
Chris@0:                             continue 2;
Chris@0:                         }
Chris@0:                         $a = null;
Chris@0:                         break;
Chris@0: 
Chris@0:                     case \is_array($v):
Chris@12:                         if (!$v) {
Chris@12:                             continue 2;
Chris@12:                         }
Chris@0:                         $stub = $arrayStub;
Chris@0:                         $stub->class = Stub::ARRAY_INDEXED;
Chris@0: 
Chris@0:                         $j = -1;
Chris@0:                         foreach ($v as $gk => $gv) {
Chris@0:                             if ($gk !== ++$j) {
Chris@0:                                 $stub->class = Stub::ARRAY_ASSOC;
Chris@0:                                 break;
Chris@0:                             }
Chris@0:                         }
Chris@0:                         $a = $v;
Chris@0: 
Chris@0:                         if (Stub::ARRAY_ASSOC === $stub->class) {
Chris@0:                             // Copies of $GLOBALS have very strange behavior,
Chris@0:                             // let's detect them with some black magic
Chris@0:                             $a[$gid] = true;
Chris@0: 
Chris@0:                             // Happens with copies of $GLOBALS
Chris@0:                             if (isset($v[$gid])) {
Chris@0:                                 unset($v[$gid]);
Chris@17:                                 $a = [];
Chris@0:                                 foreach ($v as $gk => &$gv) {
Chris@0:                                     $a[$gk] = &$gv;
Chris@0:                                 }
Chris@0:                                 unset($gv);
Chris@0:                             } else {
Chris@0:                                 $a = $v;
Chris@0:                             }
Chris@0:                         } elseif (\PHP_VERSION_ID < 70200) {
Chris@0:                             $indexedArrays[$len] = true;
Chris@0:                         }
Chris@0:                         break;
Chris@0: 
Chris@0:                     case \is_object($v):
Chris@0:                     case $v instanceof \__PHP_Incomplete_Class:
Chris@0:                         if (empty($objRefs[$h = $hashMask ^ \hexdec(\substr(\spl_object_hash($v), $hashOffset, \PHP_INT_SIZE))])) {
Chris@0:                             $stub = new Stub();
Chris@0:                             $stub->type = Stub::TYPE_OBJECT;
Chris@0:                             $stub->class = \get_class($v);
Chris@0:                             $stub->value = $v;
Chris@0:                             $stub->handle = $h;
Chris@0:                             $a = $this->castObject($stub, 0 < $i);
Chris@0:                             if ($v !== $stub->value) {
Chris@0:                                 if (Stub::TYPE_OBJECT !== $stub->type || null === $stub->value) {
Chris@0:                                     break;
Chris@0:                                 }
Chris@0:                                 $h = $hashMask ^ \hexdec(\substr(\spl_object_hash($stub->value), $hashOffset, \PHP_INT_SIZE));
Chris@0:                                 $stub->handle = $h;
Chris@0:                             }
Chris@0:                             $stub->value = null;
Chris@12:                             if (0 <= $maxItems && $maxItems <= $pos && $minimumDepthReached) {
Chris@0:                                 $stub->cut = \count($a);
Chris@0:                                 $a = null;
Chris@0:                             }
Chris@0:                         }
Chris@0:                         if (empty($objRefs[$h])) {
Chris@0:                             $objRefs[$h] = $stub;
Chris@18:                             $objects[] = $v;
Chris@0:                         } else {
Chris@0:                             $stub = $objRefs[$h];
Chris@0:                             ++$stub->refCount;
Chris@0:                             $a = null;
Chris@0:                         }
Chris@0:                         break;
Chris@0: 
Chris@0:                     default: // resource
Chris@0:                         if (empty($resRefs[$h = (int) $v])) {
Chris@0:                             $stub = new Stub();
Chris@0:                             $stub->type = Stub::TYPE_RESOURCE;
Chris@0:                             if ('Unknown' === $stub->class = @\get_resource_type($v)) {
Chris@0:                                 $stub->class = 'Closed';
Chris@0:                             }
Chris@0:                             $stub->value = $v;
Chris@0:                             $stub->handle = $h;
Chris@0:                             $a = $this->castResource($stub, 0 < $i);
Chris@0:                             $stub->value = null;
Chris@12:                             if (0 <= $maxItems && $maxItems <= $pos && $minimumDepthReached) {
Chris@0:                                 $stub->cut = \count($a);
Chris@0:                                 $a = null;
Chris@0:                             }
Chris@0:                         }
Chris@0:                         if (empty($resRefs[$h])) {
Chris@0:                             $resRefs[$h] = $stub;
Chris@0:                         } else {
Chris@0:                             $stub = $resRefs[$h];
Chris@0:                             ++$stub->refCount;
Chris@0:                             $a = null;
Chris@0:                         }
Chris@0:                         break;
Chris@0:                 }
Chris@0: 
Chris@0:                 if ($a) {
Chris@12:                     if (!$minimumDepthReached || 0 > $maxItems) {
Chris@0:                         $queue[$len] = $a;
Chris@0:                         $stub->position = $len++;
Chris@0:                     } elseif ($pos < $maxItems) {
Chris@0:                         if ($maxItems < $pos += \count($a)) {
Chris@0:                             $a = \array_slice($a, 0, $maxItems - $pos);
Chris@0:                             if ($stub->cut >= 0) {
Chris@0:                                 $stub->cut += $pos - $maxItems;
Chris@0:                             }
Chris@0:                         }
Chris@0:                         $queue[$len] = $a;
Chris@0:                         $stub->position = $len++;
Chris@0:                     } elseif ($stub->cut >= 0) {
Chris@0:                         $stub->cut += \count($a);
Chris@0:                         $stub->position = 0;
Chris@0:                     }
Chris@0:                 }
Chris@0: 
Chris@0:                 if ($arrayStub === $stub) {
Chris@0:                     if ($arrayStub->cut) {
Chris@17:                         $stub = [$arrayStub->cut, $arrayStub->class => $arrayStub->position];
Chris@0:                         $arrayStub->cut = 0;
Chris@0:                     } elseif (isset(self::$arrayCache[$arrayStub->class][$arrayStub->position])) {
Chris@0:                         $stub = self::$arrayCache[$arrayStub->class][$arrayStub->position];
Chris@0:                     } else {
Chris@17:                         self::$arrayCache[$arrayStub->class][$arrayStub->position] = $stub = [$arrayStub->class => $arrayStub->position];
Chris@0:                     }
Chris@0:                 }
Chris@0: 
Chris@0:                 if ($zvalIsRef) {
Chris@0:                     $refs[$k]->value = $stub;
Chris@0:                 } else {
Chris@0:                     $vals[$k] = $stub;
Chris@0:                 }
Chris@0:             }
Chris@0: 
Chris@0:             if ($fromObjCast) {
Chris@0:                 $fromObjCast = false;
Chris@0:                 $refs = $vals;
Chris@17:                 $vals = [];
Chris@0:                 $j = -1;
Chris@0:                 foreach ($queue[$i] as $k => $v) {
Chris@17:                     foreach ([$k => true] as $gk => $gv) {
Chris@0:                     }
Chris@0:                     if ($gk !== $k) {
Chris@0:                         $vals = (object) $vals;
Chris@0:                         $vals->{$k} = $refs[++$j];
Chris@0:                         $vals = (array) $vals;
Chris@0:                     } else {
Chris@0:                         $vals[$k] = $refs[++$j];
Chris@0:                     }
Chris@0:                 }
Chris@0:             }
Chris@0: 
Chris@0:             $queue[$i] = $vals;
Chris@0:         }
Chris@0: 
Chris@0:         foreach ($values as $h => $v) {
Chris@0:             $hardRefs[$h] = $v;
Chris@0:         }
Chris@0: 
Chris@0:         return $queue;
Chris@0:     }
Chris@0: 
Chris@0:     private static function initHashMask()
Chris@0:     {
Chris@17:         $obj = (object) [];
Chris@0:         self::$hashOffset = 16 - PHP_INT_SIZE;
Chris@0:         self::$hashMask = -1;
Chris@0: 
Chris@17:         if (\defined('HHVM_VERSION')) {
Chris@0:             self::$hashOffset += 16;
Chris@0:         } else {
Chris@0:             // check if we are nested in an output buffering handler to prevent a fatal error with ob_start() below
Chris@17:             $obFuncs = ['ob_clean', 'ob_end_clean', 'ob_flush', 'ob_end_flush', 'ob_get_contents', 'ob_get_flush'];
Chris@0:             foreach (debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS) as $frame) {
Chris@17:                 if (isset($frame['function'][0]) && !isset($frame['class']) && 'o' === $frame['function'][0] && \in_array($frame['function'], $obFuncs)) {
Chris@0:                     $frame['line'] = 0;
Chris@0:                     break;
Chris@0:                 }
Chris@0:             }
Chris@0:             if (!empty($frame['line'])) {
Chris@0:                 ob_start();
Chris@0:                 debug_zval_dump($obj);
Chris@0:                 self::$hashMask = (int) substr(ob_get_clean(), 17);
Chris@0:             }
Chris@0:         }
Chris@0: 
Chris@0:         self::$hashMask ^= hexdec(substr(spl_object_hash($obj), self::$hashOffset, PHP_INT_SIZE));
Chris@0:     }
Chris@0: }