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   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\Filesystem;
  13  
  14  use Symfony\Component\Filesystem\Exception\FileNotFoundException;
  15  use Symfony\Component\Filesystem\Exception\IOException;
  16  
  17  /**
  18   * Provides basic utility to manipulate the file system.
  19   *
  20   * @author Fabien Potencier <fabien@symfony.com>
  21   */
  22  class Filesystem
  23  {
  24      private static $lastError;
  25  
  26      /**
  27       * Copies a file.
  28       *
  29       * If the target file is older than the origin file, it's always overwritten.
  30       * If the target file is newer, it is overwritten only when the
  31       * $overwriteNewerFiles option is set to true.
  32       *
  33       * @param string $originFile          The original filename
  34       * @param string $targetFile          The target filename
  35       * @param bool   $overwriteNewerFiles If true, target files newer than origin files are overwritten
  36       *
  37       * @throws FileNotFoundException When originFile doesn't exist
  38       * @throws IOException           When copy fails
  39       */
  40      public function copy($originFile, $targetFile, $overwriteNewerFiles = false)
  41      {
  42          $originIsLocal = stream_is_local($originFile) || 0 === stripos($originFile, 'file://');
  43          if ($originIsLocal && !is_file($originFile)) {
  44              throw new FileNotFoundException(sprintf('Failed to copy "%s" because file does not exist.', $originFile), 0, null, $originFile);
  45          }
  46  
  47          $this->mkdir(\dirname($targetFile));
  48  
  49          $doCopy = true;
  50          if (!$overwriteNewerFiles && null === parse_url($originFile, \PHP_URL_HOST) && is_file($targetFile)) {
  51              $doCopy = filemtime($originFile) > filemtime($targetFile);
  52          }
  53  
  54          if ($doCopy) {
  55              // https://bugs.php.net/64634
  56              if (false === $source = @fopen($originFile, 'r')) {
  57                  throw new IOException(sprintf('Failed to copy "%s" to "%s" because source file could not be opened for reading.', $originFile, $targetFile), 0, null, $originFile);
  58              }
  59  
  60              // Stream context created to allow files overwrite when using FTP stream wrapper - disabled by default
  61              if (false === $target = @fopen($targetFile, 'w', null, stream_context_create(['ftp' => ['overwrite' => true]]))) {
  62                  throw new IOException(sprintf('Failed to copy "%s" to "%s" because target file could not be opened for writing.', $originFile, $targetFile), 0, null, $originFile);
  63              }
  64  
  65              $bytesCopied = stream_copy_to_stream($source, $target);
  66              fclose($source);
  67              fclose($target);
  68              unset($source, $target);
  69  
  70              if (!is_file($targetFile)) {
  71                  throw new IOException(sprintf('Failed to copy "%s" to "%s".', $originFile, $targetFile), 0, null, $originFile);
  72              }
  73  
  74              if ($originIsLocal) {
  75                  // Like `cp`, preserve executable permission bits
  76                  @chmod($targetFile, fileperms($targetFile) | (fileperms($originFile) & 0111));
  77  
  78                  if ($bytesCopied !== $bytesOrigin = filesize($originFile)) {
  79                      throw new IOException(sprintf('Failed to copy the whole content of "%s" to "%s" (%g of %g bytes copied).', $originFile, $targetFile, $bytesCopied, $bytesOrigin), 0, null, $originFile);
  80                  }
  81              }
  82          }
  83      }
  84  
  85      /**
  86       * Creates a directory recursively.
  87       *
  88       * @param string|iterable $dirs The directory path
  89       * @param int             $mode The directory mode
  90       *
  91       * @throws IOException On any directory creation failure
  92       */
  93      public function mkdir($dirs, $mode = 0777)
  94      {
  95          foreach ($this->toIterable($dirs) as $dir) {
  96              if (is_dir($dir)) {
  97                  continue;
  98              }
  99  
 100              if (!self::box('mkdir', $dir, $mode, true)) {
 101                  if (!is_dir($dir)) {
 102                      // The directory was not created by a concurrent process. Let's throw an exception with a developer friendly error message if we have one
 103                      if (self::$lastError) {
 104                          throw new IOException(sprintf('Failed to create "%s": ', $dir).self::$lastError, 0, null, $dir);
 105                      }
 106                      throw new IOException(sprintf('Failed to create "%s".', $dir), 0, null, $dir);
 107                  }
 108              }
 109          }
 110      }
 111  
 112      /**
 113       * Checks the existence of files or directories.
 114       *
 115       * @param string|iterable $files A filename, an array of files, or a \Traversable instance to check
 116       *
 117       * @return bool true if the file exists, false otherwise
 118       */
 119      public function exists($files)
 120      {
 121          $maxPathLength = \PHP_MAXPATHLEN - 2;
 122  
 123          foreach ($this->toIterable($files) as $file) {
 124              if (\strlen($file) > $maxPathLength) {
 125                  throw new IOException(sprintf('Could not check if file exist because path length exceeds %d characters.', $maxPathLength), 0, null, $file);
 126              }
 127  
 128              if (!file_exists($file)) {
 129                  return false;
 130              }
 131          }
 132  
 133          return true;
 134      }
 135  
 136      /**
 137       * Sets access and modification time of file.
 138       *
 139       * @param string|iterable $files A filename, an array of files, or a \Traversable instance to create
 140       * @param int|null        $time  The touch time as a Unix timestamp, if not supplied the current system time is used
 141       * @param int|null        $atime The access time as a Unix timestamp, if not supplied the current system time is used
 142       *
 143       * @throws IOException When touch fails
 144       */
 145      public function touch($files, $time = null, $atime = null)
 146      {
 147          foreach ($this->toIterable($files) as $file) {
 148              $touch = $time ? @touch($file, $time, $atime) : @touch($file);
 149              if (true !== $touch) {
 150                  throw new IOException(sprintf('Failed to touch "%s".', $file), 0, null, $file);
 151              }
 152          }
 153      }
 154  
 155      /**
 156       * Removes files or directories.
 157       *
 158       * @param string|iterable $files A filename, an array of files, or a \Traversable instance to remove
 159       *
 160       * @throws IOException When removal fails
 161       */
 162      public function remove($files)
 163      {
 164          if ($files instanceof \Traversable) {
 165              $files = iterator_to_array($files, false);
 166          } elseif (!\is_array($files)) {
 167              $files = [$files];
 168          }
 169          $files = array_reverse($files);
 170          foreach ($files as $file) {
 171              if (is_link($file)) {
 172                  // See https://bugs.php.net/52176
 173                  if (!(self::box('unlink', $file) || '\\' !== \DIRECTORY_SEPARATOR || self::box('rmdir', $file)) && file_exists($file)) {
 174                      throw new IOException(sprintf('Failed to remove symlink "%s": ', $file).self::$lastError);
 175                  }
 176              } elseif (is_dir($file)) {
 177                  $this->remove(new \FilesystemIterator($file, \FilesystemIterator::CURRENT_AS_PATHNAME | \FilesystemIterator::SKIP_DOTS));
 178  
 179                  if (!self::box('rmdir', $file) && file_exists($file)) {
 180                      throw new IOException(sprintf('Failed to remove directory "%s": ', $file).self::$lastError);
 181                  }
 182              } elseif (!self::box('unlink', $file) && (false !== strpos(self::$lastError, 'Permission denied') || file_exists($file))) {
 183                  throw new IOException(sprintf('Failed to remove file "%s": ', $file).self::$lastError);
 184              }
 185          }
 186      }
 187  
 188      /**
 189       * Change mode for an array of files or directories.
 190       *
 191       * @param string|iterable $files     A filename, an array of files, or a \Traversable instance to change mode
 192       * @param int             $mode      The new mode (octal)
 193       * @param int             $umask     The mode mask (octal)
 194       * @param bool            $recursive Whether change the mod recursively or not
 195       *
 196       * @throws IOException When the change fails
 197       */
 198      public function chmod($files, $mode, $umask = 0000, $recursive = false)
 199      {
 200          foreach ($this->toIterable($files) as $file) {
 201              if ((\PHP_VERSION_ID < 80000 || \is_int($mode)) && true !== @chmod($file, $mode & ~$umask)) {
 202                  throw new IOException(sprintf('Failed to chmod file "%s".', $file), 0, null, $file);
 203              }
 204              if ($recursive && is_dir($file) && !is_link($file)) {
 205                  $this->chmod(new \FilesystemIterator($file), $mode, $umask, true);
 206              }
 207          }
 208      }
 209  
 210      /**
 211       * Change the owner of an array of files or directories.
 212       *
 213       * @param string|iterable $files     A filename, an array of files, or a \Traversable instance to change owner
 214       * @param string|int      $user      A user name or number
 215       * @param bool            $recursive Whether change the owner recursively or not
 216       *
 217       * @throws IOException When the change fails
 218       */
 219      public function chown($files, $user, $recursive = false)
 220      {
 221          foreach ($this->toIterable($files) as $file) {
 222              if ($recursive && is_dir($file) && !is_link($file)) {
 223                  $this->chown(new \FilesystemIterator($file), $user, true);
 224              }
 225              if (is_link($file) && \function_exists('lchown')) {
 226                  if (true !== @lchown($file, $user)) {
 227                      throw new IOException(sprintf('Failed to chown file "%s".', $file), 0, null, $file);
 228                  }
 229              } else {
 230                  if (true !== @chown($file, $user)) {
 231                      throw new IOException(sprintf('Failed to chown file "%s".', $file), 0, null, $file);
 232                  }
 233              }
 234          }
 235      }
 236  
 237      /**
 238       * Change the group of an array of files or directories.
 239       *
 240       * @param string|iterable $files     A filename, an array of files, or a \Traversable instance to change group
 241       * @param string|int      $group     A group name or number
 242       * @param bool            $recursive Whether change the group recursively or not
 243       *
 244       * @throws IOException When the change fails
 245       */
 246      public function chgrp($files, $group, $recursive = false)
 247      {
 248          foreach ($this->toIterable($files) as $file) {
 249              if ($recursive && is_dir($file) && !is_link($file)) {
 250                  $this->chgrp(new \FilesystemIterator($file), $group, true);
 251              }
 252              if (is_link($file) && \function_exists('lchgrp')) {
 253                  if (true !== @lchgrp($file, $group) || (\defined('HHVM_VERSION') && !posix_getgrnam($group))) {
 254                      throw new IOException(sprintf('Failed to chgrp file "%s".', $file), 0, null, $file);
 255                  }
 256              } else {
 257                  if (true !== @chgrp($file, $group)) {
 258                      throw new IOException(sprintf('Failed to chgrp file "%s".', $file), 0, null, $file);
 259                  }
 260              }
 261          }
 262      }
 263  
 264      /**
 265       * Renames a file or a directory.
 266       *
 267       * @param string $origin    The origin filename or directory
 268       * @param string $target    The new filename or directory
 269       * @param bool   $overwrite Whether to overwrite the target if it already exists
 270       *
 271       * @throws IOException When target file or directory already exists
 272       * @throws IOException When origin cannot be renamed
 273       */
 274      public function rename($origin, $target, $overwrite = false)
 275      {
 276          // we check that target does not exist
 277          if (!$overwrite && $this->isReadable($target)) {
 278              throw new IOException(sprintf('Cannot rename because the target "%s" already exists.', $target), 0, null, $target);
 279          }
 280  
 281          if (true !== @rename($origin, $target)) {
 282              if (is_dir($origin)) {
 283                  // See https://bugs.php.net/54097 & https://php.net/rename#113943
 284                  $this->mirror($origin, $target, null, ['override' => $overwrite, 'delete' => $overwrite]);
 285                  $this->remove($origin);
 286  
 287                  return;
 288              }
 289              throw new IOException(sprintf('Cannot rename "%s" to "%s".', $origin, $target), 0, null, $target);
 290          }
 291      }
 292  
 293      /**
 294       * Tells whether a file exists and is readable.
 295       *
 296       * @param string $filename Path to the file
 297       *
 298       * @return bool
 299       *
 300       * @throws IOException When windows path is longer than 258 characters
 301       */
 302      private function isReadable($filename)
 303      {
 304          $maxPathLength = \PHP_MAXPATHLEN - 2;
 305  
 306          if (\strlen($filename) > $maxPathLength) {
 307              throw new IOException(sprintf('Could not check if file is readable because path length exceeds %d characters.', $maxPathLength), 0, null, $filename);
 308          }
 309  
 310          return is_readable($filename);
 311      }
 312  
 313      /**
 314       * Creates a symbolic link or copy a directory.
 315       *
 316       * @param string $originDir     The origin directory path
 317       * @param string $targetDir     The symbolic link name
 318       * @param bool   $copyOnWindows Whether to copy files if on Windows
 319       *
 320       * @throws IOException When symlink fails
 321       */
 322      public function symlink($originDir, $targetDir, $copyOnWindows = false)
 323      {
 324          if ('\\' === \DIRECTORY_SEPARATOR) {
 325              $originDir = strtr($originDir, '/', '\\');
 326              $targetDir = strtr($targetDir, '/', '\\');
 327  
 328              if ($copyOnWindows) {
 329                  $this->mirror($originDir, $targetDir);
 330  
 331                  return;
 332              }
 333          }
 334  
 335          $this->mkdir(\dirname($targetDir));
 336  
 337          if (is_link($targetDir)) {
 338              if (readlink($targetDir) === $originDir) {
 339                  return;
 340              }
 341              $this->remove($targetDir);
 342          }
 343  
 344          if (!self::box('symlink', $originDir, $targetDir)) {
 345              $this->linkException($originDir, $targetDir, 'symbolic');
 346          }
 347      }
 348  
 349      /**
 350       * Creates a hard link, or several hard links to a file.
 351       *
 352       * @param string          $originFile  The original file
 353       * @param string|string[] $targetFiles The target file(s)
 354       *
 355       * @throws FileNotFoundException When original file is missing or not a file
 356       * @throws IOException           When link fails, including if link already exists
 357       */
 358      public function hardlink($originFile, $targetFiles)
 359      {
 360          if (!$this->exists($originFile)) {
 361              throw new FileNotFoundException(null, 0, null, $originFile);
 362          }
 363  
 364          if (!is_file($originFile)) {
 365              throw new FileNotFoundException(sprintf('Origin file "%s" is not a file.', $originFile));
 366          }
 367  
 368          foreach ($this->toIterable($targetFiles) as $targetFile) {
 369              if (is_file($targetFile)) {
 370                  if (fileinode($originFile) === fileinode($targetFile)) {
 371                      continue;
 372                  }
 373                  $this->remove($targetFile);
 374              }
 375  
 376              if (!self::box('link', $originFile, $targetFile)) {
 377                  $this->linkException($originFile, $targetFile, 'hard');
 378              }
 379          }
 380      }
 381  
 382      /**
 383       * @param string $origin
 384       * @param string $target
 385       * @param string $linkType Name of the link type, typically 'symbolic' or 'hard'
 386       */
 387      private function linkException($origin, $target, $linkType)
 388      {
 389          if (self::$lastError) {
 390              if ('\\' === \DIRECTORY_SEPARATOR && false !== strpos(self::$lastError, 'error code(1314)')) {
 391                  throw new IOException(sprintf('Unable to create "%s" link due to error code 1314: \'A required privilege is not held by the client\'. Do you have the required Administrator-rights?', $linkType), 0, null, $target);
 392              }
 393          }
 394          throw new IOException(sprintf('Failed to create "%s" link from "%s" to "%s".', $linkType, $origin, $target), 0, null, $target);
 395      }
 396  
 397      /**
 398       * Resolves links in paths.
 399       *
 400       * With $canonicalize = false (default)
 401       *      - if $path does not exist or is not a link, returns null
 402       *      - if $path is a link, returns the next direct target of the link without considering the existence of the target
 403       *
 404       * With $canonicalize = true
 405       *      - if $path does not exist, returns null
 406       *      - if $path exists, returns its absolute fully resolved final version
 407       *
 408       * @param string $path         A filesystem path
 409       * @param bool   $canonicalize Whether or not to return a canonicalized path
 410       *
 411       * @return string|null
 412       */
 413      public function readlink($path, $canonicalize = false)
 414      {
 415          if (!$canonicalize && !is_link($path)) {
 416              return null;
 417          }
 418  
 419          if ($canonicalize) {
 420              if (!$this->exists($path)) {
 421                  return null;
 422              }
 423  
 424              if ('\\' === \DIRECTORY_SEPARATOR) {
 425                  $path = readlink($path);
 426              }
 427  
 428              return realpath($path);
 429          }
 430  
 431          if ('\\' === \DIRECTORY_SEPARATOR) {
 432              return realpath($path);
 433          }
 434  
 435          return readlink($path);
 436      }
 437  
 438      /**
 439       * Given an existing path, convert it to a path relative to a given starting path.
 440       *
 441       * @param string $endPath   Absolute path of target
 442       * @param string $startPath Absolute path where traversal begins
 443       *
 444       * @return string Path of target relative to starting path
 445       */
 446      public function makePathRelative($endPath, $startPath)
 447      {
 448          if (!$this->isAbsolutePath($endPath) || !$this->isAbsolutePath($startPath)) {
 449              @trigger_error(sprintf('Support for passing relative paths to %s() is deprecated since Symfony 3.4 and will be removed in 4.0.', __METHOD__), \E_USER_DEPRECATED);
 450          }
 451  
 452          // Normalize separators on Windows
 453          if ('\\' === \DIRECTORY_SEPARATOR) {
 454              $endPath = str_replace('\\', '/', $endPath);
 455              $startPath = str_replace('\\', '/', $startPath);
 456          }
 457  
 458          $splitDriveLetter = function ($path) {
 459              return (\strlen($path) > 2 && ':' === $path[1] && '/' === $path[2] && ctype_alpha($path[0]))
 460                  ? [substr($path, 2), strtoupper($path[0])]
 461                  : [$path, null];
 462          };
 463  
 464          $splitPath = function ($path, $absolute) {
 465              $result = [];
 466  
 467              foreach (explode('/', trim($path, '/')) as $segment) {
 468                  if ('..' === $segment && ($absolute || \count($result))) {
 469                      array_pop($result);
 470                  } elseif ('.' !== $segment && '' !== $segment) {
 471                      $result[] = $segment;
 472                  }
 473              }
 474  
 475              return $result;
 476          };
 477  
 478          list($endPath, $endDriveLetter) = $splitDriveLetter($endPath);
 479          list($startPath, $startDriveLetter) = $splitDriveLetter($startPath);
 480  
 481          $startPathArr = $splitPath($startPath, static::isAbsolutePath($startPath));
 482          $endPathArr = $splitPath($endPath, static::isAbsolutePath($endPath));
 483  
 484          if ($endDriveLetter && $startDriveLetter && $endDriveLetter != $startDriveLetter) {
 485              // End path is on another drive, so no relative path exists
 486              return $endDriveLetter.':/'.($endPathArr ? implode('/', $endPathArr).'/' : '');
 487          }
 488  
 489          // Find for which directory the common path stops
 490          $index = 0;
 491          while (isset($startPathArr[$index]) && isset($endPathArr[$index]) && $startPathArr[$index] === $endPathArr[$index]) {
 492              ++$index;
 493          }
 494  
 495          // Determine how deep the start path is relative to the common path (ie, "web/bundles" = 2 levels)
 496          if (1 === \count($startPathArr) && '' === $startPathArr[0]) {
 497              $depth = 0;
 498          } else {
 499              $depth = \count($startPathArr) - $index;
 500          }
 501  
 502          // Repeated "../" for each level need to reach the common path
 503          $traverser = str_repeat('../', $depth);
 504  
 505          $endPathRemainder = implode('/', \array_slice($endPathArr, $index));
 506  
 507          // Construct $endPath from traversing to the common path, then to the remaining $endPath
 508          $relativePath = $traverser.('' !== $endPathRemainder ? $endPathRemainder.'/' : '');
 509  
 510          return '' === $relativePath ? './' : $relativePath;
 511      }
 512  
 513      /**
 514       * Mirrors a directory to another.
 515       *
 516       * Copies files and directories from the origin directory into the target directory. By default:
 517       *
 518       *  - existing files in the target directory will be overwritten, except if they are newer (see the `override` option)
 519       *  - files in the target directory that do not exist in the source directory will not be deleted (see the `delete` option)
 520       *
 521       * @param string            $originDir The origin directory
 522       * @param string            $targetDir The target directory
 523       * @param \Traversable|null $iterator  Iterator that filters which files and directories to copy, if null a recursive iterator is created
 524       * @param array             $options   An array of boolean options
 525       *                                     Valid options are:
 526       *                                     - $options['override'] If true, target files newer than origin files are overwritten (see copy(), defaults to false)
 527       *                                     - $options['copy_on_windows'] Whether to copy files instead of links on Windows (see symlink(), defaults to false)
 528       *                                     - $options['delete'] Whether to delete files that are not in the source directory (defaults to false)
 529       *
 530       * @throws IOException When file type is unknown
 531       */
 532      public function mirror($originDir, $targetDir, \Traversable $iterator = null, $options = [])
 533      {
 534          $targetDir = rtrim($targetDir, '/\\');
 535          $originDir = rtrim($originDir, '/\\');
 536          $originDirLen = \strlen($originDir);
 537  
 538          // Iterate in destination folder to remove obsolete entries
 539          if ($this->exists($targetDir) && isset($options['delete']) && $options['delete']) {
 540              $deleteIterator = $iterator;
 541              if (null === $deleteIterator) {
 542                  $flags = \FilesystemIterator::SKIP_DOTS;
 543                  $deleteIterator = new \RecursiveIteratorIterator(new \RecursiveDirectoryIterator($targetDir, $flags), \RecursiveIteratorIterator::CHILD_FIRST);
 544              }
 545              $targetDirLen = \strlen($targetDir);
 546              foreach ($deleteIterator as $file) {
 547                  $origin = $originDir.substr($file->getPathname(), $targetDirLen);
 548                  if (!$this->exists($origin)) {
 549                      $this->remove($file);
 550                  }
 551              }
 552          }
 553  
 554          $copyOnWindows = false;
 555          if (isset($options['copy_on_windows'])) {
 556              $copyOnWindows = $options['copy_on_windows'];
 557          }
 558  
 559          if (null === $iterator) {
 560              $flags = $copyOnWindows ? \FilesystemIterator::SKIP_DOTS | \FilesystemIterator::FOLLOW_SYMLINKS : \FilesystemIterator::SKIP_DOTS;
 561              $iterator = new \RecursiveIteratorIterator(new \RecursiveDirectoryIterator($originDir, $flags), \RecursiveIteratorIterator::SELF_FIRST);
 562          }
 563  
 564          if ($this->exists($originDir)) {
 565              $this->mkdir($targetDir);
 566          }
 567  
 568          foreach ($iterator as $file) {
 569              $target = $targetDir.substr($file->getPathname(), $originDirLen);
 570  
 571              if ($copyOnWindows) {
 572                  if (is_file($file)) {
 573                      $this->copy($file, $target, isset($options['override']) ? $options['override'] : false);
 574                  } elseif (is_dir($file)) {
 575                      $this->mkdir($target);
 576                  } else {
 577                      throw new IOException(sprintf('Unable to guess "%s" file type.', $file), 0, null, $file);
 578                  }
 579              } else {
 580                  if (is_link($file)) {
 581                      $this->symlink($file->getLinkTarget(), $target);
 582                  } elseif (is_dir($file)) {
 583                      $this->mkdir($target);
 584                  } elseif (is_file($file)) {
 585                      $this->copy($file, $target, isset($options['override']) ? $options['override'] : false);
 586                  } else {
 587                      throw new IOException(sprintf('Unable to guess "%s" file type.', $file), 0, null, $file);
 588                  }
 589              }
 590          }
 591      }
 592  
 593      /**
 594       * Returns whether the file path is an absolute path.
 595       *
 596       * @param string $file A file path
 597       *
 598       * @return bool
 599       */
 600      public function isAbsolutePath($file)
 601      {
 602          return '' !== (string) $file && (strspn($file, '/\\', 0, 1)
 603              || (\strlen($file) > 3 && ctype_alpha($file[0])
 604                  && ':' === $file[1]
 605                  && strspn($file, '/\\', 2, 1)
 606              )
 607              || null !== parse_url($file, \PHP_URL_SCHEME)
 608          );
 609      }
 610  
 611      /**
 612       * Creates a temporary file with support for custom stream wrappers.
 613       *
 614       * @param string $dir    The directory where the temporary filename will be created
 615       * @param string $prefix The prefix of the generated temporary filename
 616       *                       Note: Windows uses only the first three characters of prefix
 617       *
 618       * @return string The new temporary filename (with path), or throw an exception on failure
 619       */
 620      public function tempnam($dir, $prefix)
 621      {
 622          list($scheme, $hierarchy) = $this->getSchemeAndHierarchy($dir);
 623  
 624          // If no scheme or scheme is "file" or "gs" (Google Cloud) create temp file in local filesystem
 625          if (null === $scheme || 'file' === $scheme || 'gs' === $scheme) {
 626              $tmpFile = @tempnam($hierarchy, $prefix);
 627  
 628              // If tempnam failed or no scheme return the filename otherwise prepend the scheme
 629              if (false !== $tmpFile) {
 630                  if (null !== $scheme && 'gs' !== $scheme) {
 631                      return $scheme.'://'.$tmpFile;
 632                  }
 633  
 634                  return $tmpFile;
 635              }
 636  
 637              throw new IOException('A temporary file could not be created.');
 638          }
 639  
 640          // Loop until we create a valid temp file or have reached 10 attempts
 641          for ($i = 0; $i < 10; ++$i) {
 642              // Create a unique filename
 643              $tmpFile = $dir.'/'.$prefix.uniqid(mt_rand(), true);
 644  
 645              // Use fopen instead of file_exists as some streams do not support stat
 646              // Use mode 'x+' to atomically check existence and create to avoid a TOCTOU vulnerability
 647              $handle = @fopen($tmpFile, 'x+');
 648  
 649              // If unsuccessful restart the loop
 650              if (false === $handle) {
 651                  continue;
 652              }
 653  
 654              // Close the file if it was successfully opened
 655              @fclose($handle);
 656  
 657              return $tmpFile;
 658          }
 659  
 660          throw new IOException('A temporary file could not be created.');
 661      }
 662  
 663      /**
 664       * Atomically dumps content into a file.
 665       *
 666       * @param string $filename The file to be written to
 667       * @param string $content  The data to write into the file
 668       *
 669       * @throws IOException if the file cannot be written to
 670       */
 671      public function dumpFile($filename, $content)
 672      {
 673          $dir = \dirname($filename);
 674  
 675          if (!is_dir($dir)) {
 676              $this->mkdir($dir);
 677          }
 678  
 679          if (!is_writable($dir)) {
 680              throw new IOException(sprintf('Unable to write to the "%s" directory.', $dir), 0, null, $dir);
 681          }
 682  
 683          // Will create a temp file with 0600 access rights
 684          // when the filesystem supports chmod.
 685          $tmpFile = $this->tempnam($dir, basename($filename));
 686  
 687          if (false === @file_put_contents($tmpFile, $content)) {
 688              throw new IOException(sprintf('Failed to write file "%s".', $filename), 0, null, $filename);
 689          }
 690  
 691          @chmod($tmpFile, file_exists($filename) ? fileperms($filename) : 0666 & ~umask());
 692  
 693          $this->rename($tmpFile, $filename, true);
 694      }
 695  
 696      /**
 697       * Appends content to an existing file.
 698       *
 699       * @param string $filename The file to which to append content
 700       * @param string $content  The content to append
 701       *
 702       * @throws IOException If the file is not writable
 703       */
 704      public function appendToFile($filename, $content)
 705      {
 706          $dir = \dirname($filename);
 707  
 708          if (!is_dir($dir)) {
 709              $this->mkdir($dir);
 710          }
 711  
 712          if (!is_writable($dir)) {
 713              throw new IOException(sprintf('Unable to write to the "%s" directory.', $dir), 0, null, $dir);
 714          }
 715  
 716          if (false === @file_put_contents($filename, $content, \FILE_APPEND)) {
 717              throw new IOException(sprintf('Failed to write file "%s".', $filename), 0, null, $filename);
 718          }
 719      }
 720  
 721      /**
 722       * @param mixed $files
 723       *
 724       * @return array|\Traversable
 725       */
 726      private function toIterable($files)
 727      {
 728          return \is_array($files) || $files instanceof \Traversable ? $files : [$files];
 729      }
 730  
 731      /**
 732       * Gets a 2-tuple of scheme (may be null) and hierarchical part of a filename (e.g. file:///tmp -> [file, tmp]).
 733       *
 734       * @param string $filename The filename to be parsed
 735       *
 736       * @return array The filename scheme and hierarchical part
 737       */
 738      private function getSchemeAndHierarchy($filename)
 739      {
 740          $components = explode('://', $filename, 2);
 741  
 742          return 2 === \count($components) ? [$components[0], $components[1]] : [null, $components[0]];
 743      }
 744  
 745      /**
 746       * @param callable $func
 747       *
 748       * @return mixed
 749       */
 750      private static function box($func)
 751      {
 752          self::$lastError = null;
 753          set_error_handler(__CLASS__.'::handleError');
 754          try {
 755              $result = \call_user_func_array($func, \array_slice(\func_get_args(), 1));
 756              restore_error_handler();
 757  
 758              return $result;
 759          } catch (\Throwable $e) {
 760          } catch (\Exception $e) {
 761          }
 762          restore_error_handler();
 763  
 764          throw $e;
 765      }
 766  
 767      /**
 768       * @internal
 769       */
 770      public static function handleError($type, $msg)
 771      {
 772          self::$lastError = $msg;
 773      }
 774  }