<?php
  
  /*
   * This file is part of Composer.
   *
   * (c) Nils Adermann <naderman@naderman.de>
   *     Jordi Boggiano <j.boggiano@seld.be>
   *
   * For the full copyright and license information, please view the LICENSE
   * file that was distributed with this source code.
   */
  
  setupEnvironment();
  process(is_array($argv) ? $argv : array());
  
  /**
   * Initializes various values
   *
   * @throws RuntimeException If uopz extension prevents exit calls
   */
  function setupEnvironment()
  {
      ini_set('display_errors', 1);
  
      if (extension_loaded('uopz') && !(ini_get('uopz.disable') || ini_get('uopz.exit'))) {
          // uopz works at opcode level and disables exit calls
          if (function_exists('uopz_allow_exit')) {
              @uopz_allow_exit(true);
          } else {
              throw new RuntimeException('The uopz extension ignores exit calls and breaks this installer.');
          }
      }
  
      $installer = 'ComposerInstaller';
  
      if (defined('PHP_WINDOWS_VERSION_MAJOR')) {
          if ($version = getenv('COMPOSERSETUP')) {
              $installer = sprintf('Composer-Setup.exe/%s', $version);
          }
      }
  
      define('COMPOSER_INSTALLER', $installer);
  }
  
  /**
   * Processes the installer
   */
  function process($argv)
  {
      // Determine ANSI output from --ansi and --no-ansi flags
      setUseAnsi($argv);
  
      $help = in_array('--help', $argv) || in_array('-h', $argv);
      if ($help) {
          displayHelp();
          exit(0);
      }
  
      $check      = in_array('--check', $argv);
      $force      = in_array('--force', $argv);
      $quiet      = in_array('--quiet', $argv);
      $channel    = 'stable';
      if (in_array('--snapshot', $argv)) {
          $channel = 'snapshot';
      } elseif (in_array('--preview', $argv)) {
          $channel = 'preview';
      } elseif (in_array('--1', $argv)) {
          $channel = '1';
      } elseif (in_array('--2', $argv)) {
          $channel = '2';
      } elseif (in_array('--2.2', $argv)) {
          $channel = '2.2';
      }
      $disableTls = in_array('--disable-tls', $argv);
      $installDir = getOptValue('--install-dir', $argv, false);
      $version    = getOptValue('--version', $argv, false);
      $filename   = getOptValue('--filename', $argv, 'composer.phar');
      $cafile     = getOptValue('--cafile', $argv, false);
  
      if (!checkParams($installDir, $version, $cafile)) {
          exit(1);
      }
  
      $ok = checkPlatform($warnings, $quiet, $disableTls, true);
  
      if ($check) {
          // Only show warnings if we haven't output any errors
          if ($ok) {
              showWarnings($warnings);
              showSecurityWarning($disableTls);
          }
          exit($ok ? 0 : 1);
      }
  
      if ($ok || $force) {
          if ($channel === '1' && !$quiet) {
              out('Warning: You forced the install of Composer 1.x via --1, but Composer 2.x is the latest stable version. Updating to it via composer self-update --stable is recommended.', 'error');
          }
  
          $installer = new Installer($quiet, $disableTls, $cafile);
          if ($installer->run($version, $installDir, $filename, $channel)) {
              showWarnings($warnings);
              showSecurityWarning($disableTls);
              exit(0);
          }
      }
  
      exit(1);
  }
  
  /**
   * Displays the help
   */
  function displayHelp()
  {
      echo <<<EOF
  Composer Installer
  ------------------
  Options
  --help               this help
  --check              for checking environment only
  --force              forces the installation
  --ansi               force ANSI color output
  --no-ansi            disable ANSI color output
  --quiet              do not output unimportant messages
  --install-dir="..."  accepts a target installation directory
  --preview            install the latest version from the preview (alpha/beta/rc) channel instead of stable
  --snapshot           install the latest version from the snapshot (dev builds) channel instead of stable
  --1                  install the latest stable Composer 1.x (EOL) version
  --2                  install the latest stable Composer 2.x version
  --2.2                install the latest stable Composer 2.2.x (LTS) version
  --version="..."      accepts a specific version to install instead of the latest
  --filename="..."     accepts a target filename (default: composer.phar)
  --disable-tls        disable SSL/TLS security for file downloads
  --cafile="..."       accepts a path to a Certificate Authority (CA) certificate file for SSL/TLS verification
  
  EOF;
  }
  
  /**
   * Sets the USE_ANSI define for colorizing output
   *
   * @param array $argv Command-line arguments
   */
  function setUseAnsi($argv)
  {
      // --no-ansi wins over --ansi
      if (in_array('--no-ansi', $argv)) {
          define('USE_ANSI', false);
      } elseif (in_array('--ansi', $argv)) {
          define('USE_ANSI', true);
      } else {
          define('USE_ANSI', outputSupportsColor());
      }
  }
  
  /**
   * Returns whether color output is supported
   *
   * @return bool
   */
  function outputSupportsColor()
  {
      if (false !== getenv('NO_COLOR') || !defined('STDOUT')) {
          return false;
      }
  
      if ('Hyper' === getenv('TERM_PROGRAM')) {
          return true;
      }
  
      if (defined('PHP_WINDOWS_VERSION_BUILD')) {
          return (function_exists('sapi_windows_vt100_support')
              && sapi_windows_vt100_support(STDOUT))
              || false !== getenv('ANSICON')
              || 'ON' === getenv('ConEmuANSI')
              || 'xterm' === getenv('TERM');
      }
  
      if (function_exists('stream_isatty')) {
          return stream_isatty(STDOUT);
      }
  
      if (function_exists('posix_isatty')) {
          return posix_isatty(STDOUT);
      }
  
      $stat = fstat(STDOUT);
      // Check if formatted mode is S_IFCHR
      return $stat ? 0020000 === ($stat['mode'] & 0170000) : false;
  }
  
  /**
   * Returns the value of a command-line option
   *
   * @param string $opt The command-line option to check
   * @param array $argv Command-line arguments
   * @param mixed $default Default value to be returned
   *
   * @return mixed The command-line value or the default
   */
  function getOptValue($opt, $argv, $default)
  {
      $optLength = strlen($opt);
  
      foreach ($argv as $key => $value) {
          $next = $key + 1;
          if (0 === strpos($value, $opt)) {
              if ($optLength === strlen($value) && isset($argv[$next])) {
                  return trim($argv[$next]);
              } else {
                  return trim(substr($value, $optLength + 1));
              }
          }
      }
  
      return $default;
  }
  
  /**
   * Checks that user-supplied params are valid
   *
   * @param mixed $installDir The required istallation directory
   * @param mixed $version The required composer version to install
   * @param mixed $cafile Certificate Authority file
   *
   * @return bool True if the supplied params are okay
   */
  function checkParams($installDir, $version, $cafile)
  {
      $result = true;
  
      if (false !== $installDir && !is_dir($installDir)) {
          out("The defined install dir ({$installDir}) does not exist.", 'info');
          $result = false;
      }
  
      if (false !== $version && 1 !== preg_match('/^\d+\.\d+\.\d+(\-(alpha|beta|RC)\d*)*$/', $version)) {
          out("The defined install version ({$version}) does not match release pattern.", 'info');
          $result = false;
      }
  
      if (false !== $cafile && (!file_exists($cafile) || !is_readable($cafile))) {
          out("The defined Certificate Authority (CA) cert file ({$cafile}) does not exist or is not readable.", 'info');
          $result = false;
      }
      return $result;
  }
  
  /**
   * Checks the platform for possible issues running Composer
   *
   * Errors are written to the output, warnings are saved for later display.
   *
   * @param array $warnings Populated by method, to be shown later
   * @param bool $quiet Quiet mode
   * @param bool $disableTls Bypass tls
   * @param bool $install If we are installing, rather than diagnosing
   *
   * @return bool True if there are no errors
   */
  function checkPlatform(&$warnings, $quiet, $disableTls, $install)
  {
      getPlatformIssues($errors, $warnings, $install);
  
      // Make openssl warning an error if tls has not been specifically disabled
      if (isset($warnings['openssl']) && !$disableTls) {
          $errors['openssl'] = $warnings['openssl'];
          unset($warnings['openssl']);
      }
  
      if (!empty($errors)) {
          // Composer-Setup.exe uses "Some settings" to flag platform errors
          out('Some settings on your machine make Composer unable to work properly.', 'error');
          out('Make sure that you fix the issues listed below and run this script again:', 'error');
          outputIssues($errors);
          return false;
      }
  
      if (empty($warnings) && !$quiet) {
          out('All settings correct for using Composer', 'success');
      }
      return true;
  }
  
  /**
   * Checks platform configuration for common incompatibility issues
   *
   * @param array $errors Populated by method
   * @param array $warnings Populated by method
   * @param bool $install If we are installing, rather than diagnosing
   *
   * @return bool If any errors or warnings have been found
   */
  function getPlatformIssues(&$errors, &$warnings, $install)
  {
      $errors = array();
      $warnings = array();
  
      if ($iniPath = php_ini_loaded_file()) {
          $iniMessage = PHP_EOL.'The php.ini used by your command-line PHP is: ' . $iniPath;
      } else {
          $iniMessage = PHP_EOL.'A php.ini file does not exist. You will have to create one.';
      }
      $iniMessage .= PHP_EOL.'If you can not modify the ini file, you can also run `php -d option=value` to modify ini values on the fly. You can use -d multiple times.';
  
      if (ini_get('detect_unicode')) {
          $errors['unicode'] = array(
              'The detect_unicode setting must be disabled.',
              'Add the following to the end of your `php.ini`:',
              '    detect_unicode = Off',
              $iniMessage
          );
      }
  
      if (extension_loaded('suhosin')) {
          $suhosin = ini_get('suhosin.executor.include.whitelist');
          $suhosinBlacklist = ini_get('suhosin.executor.include.blacklist');
          if (false === stripos($suhosin, 'phar') && (!$suhosinBlacklist || false !== stripos($suhosinBlacklist, 'phar'))) {
              $errors['suhosin'] = array(
                  'The suhosin.executor.include.whitelist setting is incorrect.',
                  'Add the following to the end of your `php.ini` or suhosin.ini (Example path [for Debian]: /etc/php5/cli/conf.d/suhosin.ini):',
                  '    suhosin.executor.include.whitelist = phar '.$suhosin,
                  $iniMessage
              );
          }
      }
  
      if (!function_exists('json_decode')) {
          $errors['json'] = array(
              'The json extension is missing.',
              'Install it or recompile php without --disable-json'
          );
      }
  
      if (!extension_loaded('Phar')) {
          $errors['phar'] = array(
              'The phar extension is missing.',
              'Install it or recompile php without --disable-phar'
          );
      }
  
      if (!extension_loaded('filter')) {
          $errors['filter'] = array(
              'The filter extension is missing.',
              'Install it or recompile php without --disable-filter'
          );
      }
  
      if (!extension_loaded('hash')) {
          $errors['hash'] = array(
              'The hash extension is missing.',
              'Install it or recompile php without --disable-hash'
          );
      }
  
      if (!extension_loaded('iconv') && !extension_loaded('mbstring')) {
          $errors['iconv_mbstring'] = array(
              'The iconv OR mbstring extension is required and both are missing.',
              'Install either of them or recompile php without --disable-iconv'
          );
      }
  
      if (!ini_get('allow_url_fopen')) {
          $errors['allow_url_fopen'] = array(
              'The allow_url_fopen setting is incorrect.',
              'Add the following to the end of your `php.ini`:',
              '    allow_url_fopen = On',
              $iniMessage
          );
      }
  
      if (extension_loaded('ionCube Loader') && ioncube_loader_iversion() < 40009) {
          $ioncube = ioncube_loader_version();
          $errors['ioncube'] = array(
              'Your ionCube Loader extension ('.$ioncube.') is incompatible with Phar files.',
              'Upgrade to ionCube 4.0.9 or higher or remove this line (path may be different) from your `php.ini` to disable it:',
              '    zend_extension = /usr/lib/php5/20090626+lfs/ioncube_loader_lin_5.3.so',
              $iniMessage
          );
      }
  
      if (version_compare(PHP_VERSION, '5.3.2', '<')) {
          $errors['php'] = array(
              'Your PHP ('.PHP_VERSION.') is too old, you must upgrade to PHP 5.3.2 or higher.'
          );
      }
  
      if (version_compare(PHP_VERSION, '5.3.4', '<')) {
          $warnings['php'] = array(
              'Your PHP ('.PHP_VERSION.') is quite old, upgrading to PHP 5.3.4 or higher is recommended.',
              'Composer works with 5.3.2+ for most people, but there might be edge case issues.'
          );
      }
  
      if (!extension_loaded('openssl')) {
          $warnings['openssl'] = array(
              'The openssl extension is missing, which means that secure HTTPS transfers are impossible.',
              'If possible you should enable it or recompile php with --with-openssl'
          );
      }
  
      if (extension_loaded('openssl') && OPENSSL_VERSION_NUMBER < 0x1000100f) {
          // Attempt to parse version number out, fallback to whole string value.
          $opensslVersion = trim(strstr(OPENSSL_VERSION_TEXT, ' '));
          $opensslVersion = substr($opensslVersion, 0, strpos($opensslVersion, ' '));
          $opensslVersion = $opensslVersion ? $opensslVersion : OPENSSL_VERSION_TEXT;
  
          $warnings['openssl_version'] = array(
              'The OpenSSL library ('.$opensslVersion.') used by PHP does not support TLSv1.2 or TLSv1.1.',
              'If possible you should upgrade OpenSSL to version 1.0.1 or above.'
          );
      }
  
      if (!defined('HHVM_VERSION') && !extension_loaded('apcu') && ini_get('apc.enable_cli')) {
          $warnings['apc_cli'] = array(
              'The apc.enable_cli setting is incorrect.',
              'Add the following to the end of your `php.ini`:',
              '    apc.enable_cli = Off',
              $iniMessage
          );
      }
  
      if (!$install && extension_loaded('xdebug')) {
          $warnings['xdebug_loaded'] = array(
              'The xdebug extension is loaded, this can slow down Composer a little.',
              'Disabling it when using Composer is recommended.'
          );
  
          if (ini_get('xdebug.profiler_enabled')) {
              $warnings['xdebug_profile'] = array(
                  'The xdebug.profiler_enabled setting is enabled, this can slow down Composer a lot.',
                  'Add the following to the end of your `php.ini` to disable it:',
                  '    xdebug.profiler_enabled = 0',
                  $iniMessage
              );
          }
      }
  
      if (!extension_loaded('zlib')) {
          $warnings['zlib'] = array(
              'The zlib extension is not loaded, this can slow down Composer a lot.',
              'If possible, install it or recompile php with --with-zlib',
              $iniMessage
          );
      }
  
      if (defined('PHP_WINDOWS_VERSION_BUILD')
          && (version_compare(PHP_VERSION, '7.2.23', '<')
          || (version_compare(PHP_VERSION, '7.3.0', '>=')
          && version_compare(PHP_VERSION, '7.3.10', '<')))) {
          $warnings['onedrive'] = array(
              'The Windows OneDrive folder is not supported on PHP versions below 7.2.23 and 7.3.10.',
              'Upgrade your PHP ('.PHP_VERSION.') to use this location with Composer.'
          );
      }
  
      if (extension_loaded('uopz') && !(ini_get('uopz.disable') || ini_get('uopz.exit'))) {
          $warnings['uopz'] = array(
              'The uopz extension ignores exit calls and may not work with all Composer commands.',
              'Disabling it when using Composer is recommended.'
          );
      }
  
      ob_start();
      phpinfo(INFO_GENERAL);
      $phpinfo = ob_get_clean();
      if (preg_match('{Configure Command(?: *</td><td class="v">| *=> *)(.*?)(?:</td>|$)}m', $phpinfo, $match)) {
          $configure = $match[1];
  
          if (false !== strpos($configure, '--enable-sigchild')) {
              $warnings['sigchild'] = array(
                  'PHP was compiled with --enable-sigchild which can cause issues on some platforms.',
                  'Recompile it without this flag if possible, see also:',
                  '    https://bugs.php.net/bug.php?id=22999'
              );
          }
  
          if (false !== strpos($configure, '--with-curlwrappers')) {
              $warnings['curlwrappers'] = array(
                  'PHP was compiled with --with-curlwrappers which will cause issues with HTTP authentication and GitHub.',
                  'Recompile it without this flag if possible'
              );
          }
      }
  
      // Stringify the message arrays
      foreach ($errors as $key => $value) {
          $errors[$key] = PHP_EOL.implode(PHP_EOL, $value);
      }
  
      foreach ($warnings as $key => $value) {
          $warnings[$key] = PHP_EOL.implode(PHP_EOL, $value);
      }
  
      return !empty($errors) || !empty($warnings);
  }
  
  
  /**
   * Outputs an array of issues
   *
   * @param array $issues
   */
  function outputIssues($issues)
  {
      foreach ($issues as $issue) {
          out($issue, 'info');
      }
      out('');
  }
  
  /**
   * Outputs any warnings found
   *
   * @param array $warnings
   */
  function showWarnings($warnings)
  {
      if (!empty($warnings)) {
          out('Some settings on your machine may cause stability issues with Composer.', 'error');
          out('If you encounter issues, try to change the following:', 'error');
          outputIssues($warnings);
      }
  }
  
  /**
   * Outputs an end of process warning if tls has been bypassed
   *
   * @param bool $disableTls Bypass tls
   */
  function showSecurityWarning($disableTls)
  {
      if ($disableTls) {
          out('You have instructed the Installer not to enforce SSL/TLS security on remote HTTPS requests.', 'info');
          out('This will leave all downloads during installation vulnerable to Man-In-The-Middle (MITM) attacks', 'info');
      }
  }
  
  /**
   * colorize output
   */
  function out($text, $color = null, $newLine = true)
  {
      $styles = array(
          'success' => "\033[0;32m%s\033[0m",
          'error' => "\033[31;31m%s\033[0m",
          'info' => "\033[33;33m%s\033[0m"
      );
  
      $format = '%s';
  
      if (isset($styles[$color]) && USE_ANSI) {
          $format = $styles[$color];
      }
  
      if ($newLine) {
          $format .= PHP_EOL;
      }
  
      printf($format, $text);
  }
  
  /**
   * Returns the system-dependent Composer home location, which may not exist
   *
   * @return string
   */
  function getHomeDir()
  {
      $home = getenv('COMPOSER_HOME');
      if ($home) {
          return $home;
      }
  
      $userDir = getUserDir();
  
      if (defined('PHP_WINDOWS_VERSION_MAJOR')) {
          return $userDir.'/Composer';
      }
  
      $dirs = array();
  
      if (useXdg()) {
          // XDG Base Directory Specifications
          $xdgConfig = getenv('XDG_CONFIG_HOME');
          if (!$xdgConfig) {
              $xdgConfig = $userDir . '/.config';
          }
  
          $dirs[] = $xdgConfig . '/composer';
      }
  
      $dirs[] = $userDir . '/.composer';
  
      // select first dir which exists of: $XDG_CONFIG_HOME/composer or ~/.composer
      foreach ($dirs as $dir) {
          if (is_dir($dir)) {
              return $dir;
          }
      }
  
      // if none exists, we default to first defined one (XDG one if system uses it, or ~/.composer otherwise)
      return $dirs[0];
  }
  
  /**
   * Returns the location of the user directory from the environment
   * @throws RuntimeException If the environment value does not exists
   *
   * @return string
   */
  function getUserDir()
  {
      $userEnv = defined('PHP_WINDOWS_VERSION_MAJOR') ? 'APPDATA' : 'HOME';
      $userDir = getenv($userEnv);
  
      if (!$userDir) {
          throw new RuntimeException('The '.$userEnv.' or COMPOSER_HOME environment variable must be set for composer to run correctly');
      }
  
      return rtrim(strtr($userDir, '\\', '/'), '/');
  }
  
  /**
   * @return bool
   */
  function useXdg()
  {
      foreach (array_keys($_SERVER) as $key) {
          if (strpos($key, 'XDG_') === 0) {
              return true;
          }
      }
  
      if (is_dir('/etc/xdg')) {
          return true;
      }
  
      return false;
  }
  
  function validateCaFile($contents)
  {
      // assume the CA is valid if php is vulnerable to
      // https://www.sektioneins.de/advisories/advisory-012013-php-openssl_x509_parse-memory-corruption-vulnerability.html
      if (
          PHP_VERSION_ID <= 50327
          || (PHP_VERSION_ID >= 50400 && PHP_VERSION_ID < 50422)
          || (PHP_VERSION_ID >= 50500 && PHP_VERSION_ID < 50506)
      ) {
          return !empty($contents);
      }
  
      return (bool) openssl_x509_parse($contents);
  }
  
  class Installer
  {
      private $quiet;
      private $disableTls;
      private $cafile;
      private $displayPath;
      private $target;
      private $tmpFile;
      private $tmpCafile;
      private $baseUrl;
      private $algo;
      private $errHandler;
      private $httpClient;
      private $pubKeys = array();
      private $installs = array();
  
      /**
       * Constructor - must not do anything that throws an exception
       *
       * @param bool $quiet Quiet mode
       * @param bool $disableTls Bypass tls
       * @param mixed $cafile Path to CA bundle, or false
       */
      public function __construct($quiet, $disableTls, $caFile)
      {
          if (($this->quiet = $quiet)) {
              ob_start();
          }
          $this->disableTls = $disableTls;
          $this->cafile = $caFile;
          $this->errHandler = new ErrorHandler();
      }
  
      /**
       * Runs the installer
       *
       * @param mixed $version Specific version to install, or false
       * @param mixed $installDir Specific installation directory, or false
       * @param string $filename Specific filename to save to, or composer.phar
       * @param string $channel Specific version channel to use
       * @throws Exception If anything other than a RuntimeException is caught
       *
       * @return bool If the installation succeeded
       */
      public function run($version, $installDir, $filename, $channel)
      {
          try {
              $this->initTargets($installDir, $filename);
              $this->initTls();
              $this->httpClient = new HttpClient($this->disableTls, $this->cafile);
              $result = $this->install($version, $channel);
  
              // in case --1 or --2 is passed, we leave the default channel for next self-update to stable
              if (1 === preg_match('{^\d+$}D', $channel)) {
                  $channel = 'stable';
              }
  
              if ($result && $channel !== 'stable' && !$version && defined('PHP_BINARY')) {
                  $null = (defined('PHP_WINDOWS_VERSION_MAJOR') ? 'NUL' : '/dev/null');
                  @exec(escapeshellarg(PHP_BINARY) .' '.escapeshellarg($this->target).' self-update --'.$channel.' --set-channel-only -q > '.$null.' 2> '.$null, $output);
              }
          } catch (Exception $e) {
              $result = false;
          }
  
          // Always clean up
          $this->cleanUp($result);
  
          if (isset($e)) {
              // Rethrow anything that is not a RuntimeException
              if (!$e instanceof RuntimeException) {
                  throw $e;
              }
              out($e->getMessage(), 'error');
          }
          return $result;
      }
  
      /**
       * Initialization methods to set the required filenames and composer url
       *
       * @param mixed $installDir Specific installation directory, or false
       * @param string $filename Specific filename to save to, or composer.phar
       * @throws RuntimeException If the installation directory is not writable
       */
      protected function initTargets($installDir, $filename)
      {
          $this->displayPath = ($installDir ? rtrim($installDir, '/').'/' : '').$filename;
          $installDir = $installDir ? realpath($installDir) : getcwd();
  
          if (!is_writeable($installDir)) {
              throw new RuntimeException('The installation directory "'.$installDir.'" is not writable');
          }
  
          $this->target = $installDir.DIRECTORY_SEPARATOR.$filename;
          $this->tmpFile = $installDir.DIRECTORY_SEPARATOR.basename($this->target, '.phar').'-temp.phar';
  
          $uriScheme = $this->disableTls ? 'http' : 'https';
          $this->baseUrl = $uriScheme.'://getcomposer.org';
      }
  
      /**
       * A wrapper around methods to check tls and write public keys
       * @throws RuntimeException If SHA384 is not supported
       */
      protected function initTls()
      {
          if ($this->disableTls) {
              return;
          }
  
          if (!in_array('sha384', array_map('strtolower', openssl_get_md_methods()))) {
              throw new RuntimeException('SHA384 is not supported by your openssl extension');
          }
  
          $this->algo = defined('OPENSSL_ALGO_SHA384') ? OPENSSL_ALGO_SHA384 : 'SHA384';
          $home = $this->getComposerHome();
  
          $this->pubKeys = array(
              'dev' => $this->installKey(self::getPKDev(), $home, 'keys.dev.pub'),
              'tags' => $this->installKey(self::getPKTags(), $home, 'keys.tags.pub')
          );
  
          if (empty($this->cafile) && !HttpClient::getSystemCaRootBundlePath()) {
              $this->cafile = $this->tmpCafile = $this->installKey(HttpClient::getPackagedCaFile(), $home, 'cacert-temp.pem');
          }
      }
  
      /**
       * Returns the Composer home directory, creating it if required
       * @throws RuntimeException If the directory cannot be created
       *
       * @return string
       */
      protected function getComposerHome()
      {
          $home = getHomeDir();
  
          if (!is_dir($home)) {
              $this->errHandler->start();
  
              if (!mkdir($home, 0777, true)) {
                  throw new RuntimeException(sprintf(
                      'Unable to create Composer home directory "%s": %s',
                      $home,
                      $this->errHandler->message
                  ));
              }
              $this->installs[] = $home;
              $this->errHandler->stop();
          }
          return $home;
      }
  
      /**
       * Writes public key data to disc
       *
       * @param string $data The public key(s) in pem format
       * @param string $path The directory to write to
       * @param string $filename The name of the file
       * @throws RuntimeException If the file cannot be written
       *
       * @return string The path to the saved data
       */
      protected function installKey($data, $path, $filename)
      {
          $this->errHandler->start();
  
          $target = $path.DIRECTORY_SEPARATOR.$filename;
          $installed = file_exists($target);
          $write = file_put_contents($target, $data, LOCK_EX);
          @chmod($target, 0644);
  
          $this->errHandler->stop();
  
          if (!$write) {
              throw new RuntimeException(sprintf('Unable to write %s to: %s', $filename, $path));
          }
  
          if (!$installed) {
              $this->installs[] = $target;
          }
  
          return $target;
      }
  
      /**
       * The main install function
       *
       * @param mixed $version Specific version to install, or false
       * @param string $channel Version channel to use
       *
       * @return bool If the installation succeeded
       */
      protected function install($version, $channel)
      {
          $retries = 3;
          $result = false;
          $infoMsg = 'Downloading...';
          $infoType = 'info';
  
          while ($retries--) {
              if (!$this->quiet) {
                  out($infoMsg, $infoType);
                  $infoMsg = 'Retrying...';
                  $infoType = 'error';
              }
  
              if (!$this->getVersion($channel, $version, $url, $error)) {
                  out($error, 'error');
                  continue;
              }
  
              if (!$this->downloadToTmp($url, $signature, $error)) {
                  out($error, 'error');
                  continue;
              }
  
              if (!$this->verifyAndSave($version, $signature, $error)) {
                  out($error, 'error');
                  continue;
              }
  
              $result = true;
              break;
          }
  
          if (!$this->quiet) {
              if ($result) {
                  out(PHP_EOL."Composer (version {$version}) successfully installed to: {$this->target}", 'success');
                  out("Use it: php {$this->displayPath}", 'info');
                  out('');
              } else {
                  out('The download failed repeatedly, aborting.', 'error');
              }
          }
          return $result;
      }
  
      /**
       * Sets the version url, downloading version data if required
       *
       * @param string $channel Version channel to use
       * @param false|string $version Version to install, or set by method
       * @param null|string $url The versioned url, set by method
       * @param null|string $error Set by method on failure
       *
       * @return bool If the operation succeeded
       */
      protected function getVersion($channel, &$version, &$url, &$error)
      {
          $error = '';
  
          if ($version) {
              if (empty($url)) {
                  $url = $this->baseUrl."/download/{$version}/composer.phar";
              }
              return true;
          }
  
          $this->errHandler->start();
  
          if ($this->downloadVersionData($data, $error)) {
              $this->parseVersionData($data, $channel, $version, $url);
          }
  
          $this->errHandler->stop();
          return empty($error);
      }
  
      /**
       * Downloads and json-decodes version data
       *
       * @param null|array $data Downloaded version data, set by method
       * @param null|string $error Set by method on failure
       *
       * @return bool If the operation succeeded
       */
      protected function downloadVersionData(&$data, &$error)
      {
          $url = $this->baseUrl.'/versions';
          $errFmt = 'The "%s" file could not be %s: %s';
  
          if (!$json = $this->httpClient->get($url)) {
              $error = sprintf($errFmt, $url, 'downloaded', $this->errHandler->message);
              return false;
          }
  
          if (!$data = json_decode($json, true)) {
              $error = sprintf($errFmt, $url, 'json-decoded', $this->getJsonError());
              return false;
          }
          return true;
      }
  
      /**
       * A wrapper around the methods needed to download and save the phar
       *
       * @param string $url The versioned download url
       * @param null|string $signature Set by method on successful download
       * @param null|string $error Set by method on failure
       *
       * @return bool If the operation succeeded
       */
      protected function downloadToTmp($url, &$signature, &$error)
      {
          $error = '';
          $errFmt = 'The "%s" file could not be downloaded: %s';
          $sigUrl = $url.'.sig';
          $this->errHandler->start();
  
          if (!$fh = fopen($this->tmpFile, 'w')) {
              $error = sprintf('Could not create file "%s": %s', $this->tmpFile, $this->errHandler->message);
  
          } elseif (!$this->getSignature($sigUrl, $signature)) {
              $error = sprintf($errFmt, $sigUrl, $this->errHandler->message);
  
          } elseif (!fwrite($fh, $this->httpClient->get($url))) {
              $error = sprintf($errFmt, $url, $this->errHandler->message);
          }
  
          if (is_resource($fh)) {
              fclose($fh);
          }
          $this->errHandler->stop();
          return empty($error);
      }
  
      /**
       * Verifies the downloaded file and saves it to the target location
       *
       * @param string $version The composer version downloaded
       * @param string $signature The digital signature to check
       * @param null|string $error Set by method on failure
       *
       * @return bool If the operation succeeded
       */
      protected function verifyAndSave($version, $signature, &$error)
      {
          $error = '';
  
          if (!$this->validatePhar($this->tmpFile, $pharError)) {
              $error = 'The download is corrupt: '.$pharError;
  
          } elseif (!$this->verifySignature($version, $signature, $this->tmpFile)) {
              $error = 'Signature mismatch, could not verify the phar file integrity';
  
          } else {
              $this->errHandler->start();
  
              if (!rename($this->tmpFile, $this->target)) {
                  $error = sprintf('Could not write to file "%s": %s', $this->target, $this->errHandler->message);
              }
              chmod($this->target, 0755);
              $this->errHandler->stop();
          }
  
          return empty($error);
      }
  
      /**
       * Parses an array of version data to match the required channel
       *
       * @param array $data Downloaded version data
       * @param mixed $channel Version channel to use
       * @param false|string $version Set by method
       * @param mixed $url The versioned url, set by method
       */
      protected function parseVersionData(array $data, $channel, &$version, &$url)
      {
          foreach ($data[$channel] as $candidate) {
              if ($candidate['min-php'] <= PHP_VERSION_ID) {
                  $version = $candidate['version'];
                  $url = $this->baseUrl.$candidate['path'];
                  break;
              }
          }
  
          if (!$version) {
              $error = sprintf(
                  'None of the %d %s version(s) of Composer matches your PHP version (%s / ID: %d)',
                  count($data[$channel]),
                  $channel,
                  PHP_VERSION,
                  PHP_VERSION_ID
              );
              throw new RuntimeException($error);
          }
      }
  
      /**
       * Downloads the digital signature of required phar file
       *
       * @param string $url The signature url
       * @param null|string $signature Set by method on success
       *
       * @return bool If the download succeeded
       */
      protected function getSignature($url, &$signature)
      {
          if (!$result = $this->disableTls) {
              $signature = $this->httpClient->get($url);
  
              if ($signature) {
                  $signature = json_decode($signature, true);
                  $signature = base64_decode($signature['sha384']);
                  $result = true;
              }
          }
  
          return $result;
      }
  
      /**
       * Verifies the signature of the downloaded phar
       *
       * @param string $version The composer versione
       * @param string $signature The downloaded digital signature
       * @param string $file The temp phar file
       *
       * @return bool If the operation succeeded
       */
      protected function verifySignature($version, $signature, $file)
      {
          if (!$result = $this->disableTls) {
              $path = preg_match('{^[0-9a-f]{40}$}', $version) ? $this->pubKeys['dev'] : $this->pubKeys['tags'];
              $pubkeyid = openssl_pkey_get_public('file://'.$path);
  
              $result = 1 === openssl_verify(
                  file_get_contents($file),
                  $signature,
                  $pubkeyid,
                  $this->algo
              );
  
              // PHP 8 automatically frees the key instance and deprecates the function
              if (PHP_VERSION_ID < 80000) {
                  openssl_free_key($pubkeyid);
              }
          }
  
          return $result;
      }
  
      /**
       * Validates the downloaded phar file
       *
       * @param string $pharFile The temp phar file
       * @param null|string $error Set by method on failure
       *
       * @return bool If the operation succeeded
       */
      protected function validatePhar($pharFile, &$error)
      {
          if (ini_get('phar.readonly')) {
              return true;
          }
  
          try {
              // Test the phar validity
              $phar = new Phar($pharFile);
              // Free the variable to unlock the file
              unset($phar);
              $result = true;
  
          } catch (Exception $e) {
              if (!$e instanceof UnexpectedValueException && !$e instanceof PharException) {
                  throw $e;
              }
              $error = $e->getMessage();
              $result = false;
          }
          return $result;
      }
  
      /**
       * Returns a string representation of the last json error
       *
       * @return string The error string or code
       */
      protected function getJsonError()
      {
          if (function_exists('json_last_error_msg')) {
              return json_last_error_msg();
          } else {
              return 'json_last_error = '.json_last_error();
          }
      }
  
      /**
       * Cleans up resources at the end of the installation
       *
       * @param bool $result If the installation succeeded
       */
      protected function cleanUp($result)
      {
          if (!$result) {
              // Output buffered errors
              if ($this->quiet) {
                  $this->outputErrors();
              }
              // Clean up stuff we created
              $this->uninstall();
          } elseif ($this->tmpCafile) {
              @unlink($this->tmpCafile);
          }
      }
  
      /**
       * Outputs unique errors when in quiet mode
       *
       */
      protected function outputErrors()
      {
          $errors = explode(PHP_EOL, ob_get_clean());
          $shown = array();
  
          foreach ($errors as $error) {
              if ($error && !in_array($error, $shown)) {
                  out($error, 'error');
                  $shown[] = $error;
              }
          }
      }
  
      /**
       * Uninstalls newly-created files and directories on failure
       *
       */
      protected function uninstall()
      {
          foreach (array_reverse($this->installs) as $target) {
              if (is_file($target)) {
                  @unlink($target);
              } elseif (is_dir($target)) {
                  @rmdir($target);
              }
          }
  
          if ($this->tmpFile !== null && file_exists($this->tmpFile)) {
              @unlink($this->tmpFile);
          }
      }
  
      public static function getPKDev()
      {
          return <<<PKDEV
  -----BEGIN PUBLIC KEY-----
  MIICIjANBgkqhkiG9w0BAQEFAAOCAg8AMIICCgKCAgEAnBDHjZS6e0ZMoK3xTD7f
  FNCzlXjX/Aie2dit8QXA03pSrOTbaMnxON3hUL47Lz3g1SC6YJEMVHr0zYq4elWi
  i3ecFEgzLcj+pZM5X6qWu2Ozz4vWx3JYo1/a/HYdOuW9e3lwS8VtS0AVJA+U8X0A
  hZnBmGpltHhO8hPKHgkJtkTUxCheTcbqn4wGHl8Z2SediDcPTLwqezWKUfrYzu1f
  o/j3WFwFs6GtK4wdYtiXr+yspBZHO3y1udf8eFFGcb2V3EaLOrtfur6XQVizjOuk
  8lw5zzse1Qp/klHqbDRsjSzJ6iL6F4aynBc6Euqt/8ccNAIz0rLjLhOraeyj4eNn
  8iokwMKiXpcrQLTKH+RH1JCuOVxQ436bJwbSsp1VwiqftPQieN+tzqy+EiHJJmGf
  TBAbWcncicCk9q2md+AmhNbvHO4PWbbz9TzC7HJb460jyWeuMEvw3gNIpEo2jYa9
  pMV6cVqnSa+wOc0D7pC9a6bne0bvLcm3S+w6I5iDB3lZsb3A9UtRiSP7aGSo7D72
  8tC8+cIgZcI7k9vjvOqH+d7sdOU2yPCnRY6wFh62/g8bDnUpr56nZN1G89GwM4d4
  r/TU7BQQIzsZgAiqOGXvVklIgAMiV0iucgf3rNBLjjeNEwNSTTG9F0CtQ+7JLwaE
  wSEuAuRm+pRqi8BRnQ/GKUcCAwEAAQ==
  -----END PUBLIC KEY-----
  PKDEV;
      }
  
      public static function getPKTags()
      {
          return <<<PKTAGS
  -----BEGIN PUBLIC KEY-----
  MIICIjANBgkqhkiG9w0BAQEFAAOCAg8AMIICCgKCAgEA0Vi/2K6apCVj76nCnCl2
  MQUPdK+A9eqkYBacXo2wQBYmyVlXm2/n/ZsX6pCLYPQTHyr5jXbkQzBw8SKqPdlh
  vA7NpbMeNCz7wP/AobvUXM8xQuXKbMDTY2uZ4O7sM+PfGbptKPBGLe8Z8d2sUnTO
  bXtX6Lrj13wkRto7st/w/Yp33RHe9SlqkiiS4MsH1jBkcIkEHsRaveZzedUaxY0M
  mba0uPhGUInpPzEHwrYqBBEtWvP97t2vtfx8I5qv28kh0Y6t+jnjL1Urid2iuQZf
  noCMFIOu4vksK5HxJxxrN0GOmGmwVQjOOtxkwikNiotZGPR4KsVj8NnBrLX7oGuM
  nQvGciiu+KoC2r3HDBrpDeBVdOWxDzT5R4iI0KoLzFh2pKqwbY+obNPS2bj+2dgJ
  rV3V5Jjry42QOCBN3c88wU1PKftOLj2ECpewY6vnE478IipiEu7EAdK8Zwj2LmTr
  RKQUSa9k7ggBkYZWAeO/2Ag0ey3g2bg7eqk+sHEq5ynIXd5lhv6tC5PBdHlWipDK
  tl2IxiEnejnOmAzGVivE1YGduYBjN+mjxDVy8KGBrjnz1JPgAvgdwJ2dYw4Rsc/e
  TzCFWGk/HM6a4f0IzBWbJ5ot0PIi4amk07IotBXDWwqDiQTwyuGCym5EqWQ2BD95
  RGv89BPD+2DLnJysngsvVaUCAwEAAQ==
  -----END PUBLIC KEY-----
  PKTAGS;
      }
  }
  
  class ErrorHandler
  {
      public $message;
      protected $active;
  
      /**
       * Handle php errors
       *
       * @param mixed $code The error code
       * @param mixed $msg The error message
       */
      public function handleError($code, $msg)
      {
          if ($this->message) {
              $this->message .= PHP_EOL;
          }
          $this->message .= preg_replace('{^file_get_contents\(.*?\): }', '', $msg);
      }
  
      /**
       * Starts error-handling if not already active
       *
       * Any message is cleared
       */
      public function start()
      {
          if (!$this->active) {
              set_error_handler(array($this, 'handleError'));
              $this->active = true;
          }
          $this->message = '';
      }
  
      /**
       * Stops error-handling if active
       *
       * Any message is preserved until the next call to start()
       */
      public function stop()
      {
          if ($this->active) {
              restore_error_handler();
              $this->active = false;
          }
      }
  }
  
  class NoProxyPattern
  {
      private $composerInNoProxy = false;
      private $rulePorts = array();
  
      public function __construct($pattern)
      {
          $rules = preg_split('{[\s,]+}', $pattern, null, PREG_SPLIT_NO_EMPTY);
  
          if ($matches = preg_grep('{getcomposer\.org(?::\d+)?}i', $rules)) {
              $this->composerInNoProxy = true;
  
              foreach ($matches as $match) {
                  if (strpos($match, ':') !== false) {
                      list(, $port) = explode(':', $match);
                      $this->rulePorts[] = (int) $port;
                  }
              }
          }
      }
  
      /**
       * Returns true if NO_PROXY contains getcomposer.org
       *
       * @param string $url http(s)://getcomposer.org
       *
       * @return bool
       */
      public function test($url)
      {
          if (!$this->composerInNoProxy) {
              return false;
          }
  
          if (empty($this->rulePorts)) {
              return true;
          }
  
          if (strpos($url, 'http://') === 0) {
              $port = 80;
          } else {
              $port = 443;
          }
  
          return in_array($port, $this->rulePorts);
      }
  }
  
  class HttpClient {
  
      private $options = array('http' => array());
      private $disableTls = false;
  
      public function __construct($disableTls = false, $cafile = false)
      {
          $this->disableTls = $disableTls;
          if ($this->disableTls === false) {
              if (!empty($cafile) && !is_dir($cafile)) {
                  if (!is_readable($cafile) || !validateCaFile(file_get_contents($cafile))) {
                      throw new RuntimeException('The configured cafile (' .$cafile. ') was not valid or could not be read.');
                  }
              }
              $options = $this->getTlsStreamContextDefaults($cafile);
              $this->options = array_replace_recursive($this->options, $options);
          }
      }
  
      public function get($url)
      {
          $context = $this->getStreamContext($url);
          $result = file_get_contents($url, false, $context);
  
          if ($result && extension_loaded('zlib')) {
              $decode = false;
              foreach ($http_response_header as $header) {
                  if (preg_match('{^content-encoding: *gzip *$}i', $header)) {
                      $decode = true;
                      continue;
                  } elseif (preg_match('{^HTTP/}i', $header)) {
                      $decode = false;
                  }
              }
  
              if ($decode) {
                  if (version_compare(PHP_VERSION, '5.4.0', '>=')) {
                      $result = zlib_decode($result);
                  } else {
                      // work around issue with gzuncompress & co that do not work with all gzip checksums
                      $result = file_get_contents('compress.zlib://data:application/octet-stream;base64,'.base64_encode($result));
                  }
  
                  if (!$result) {
                      throw new RuntimeException('Failed to decode zlib stream');
                  }
              }
          }
  
          return $result;
      }
  
      protected function getStreamContext($url)
      {
          if ($this->disableTls === false) {
              if (PHP_VERSION_ID < 50600) {
                  $this->options['ssl']['SNI_server_name'] = parse_url($url, PHP_URL_HOST);
              }
          }
          // Keeping the above mostly isolated from the code copied from Composer.
          return $this->getMergedStreamContext($url);
      }
  
      protected function getTlsStreamContextDefaults($cafile)
      {
          $ciphers = implode(':', array(
              'ECDHE-RSA-AES128-GCM-SHA256',
              'ECDHE-ECDSA-AES128-GCM-SHA256',
              'ECDHE-RSA-AES256-GCM-SHA384',
              'ECDHE-ECDSA-AES256-GCM-SHA384',
              'DHE-RSA-AES128-GCM-SHA256',
              'DHE-DSS-AES128-GCM-SHA256',
              'kEDH+AESGCM',
              'ECDHE-RSA-AES128-SHA256',
              'ECDHE-ECDSA-AES128-SHA256',
              'ECDHE-RSA-AES128-SHA',
              'ECDHE-ECDSA-AES128-SHA',
              'ECDHE-RSA-AES256-SHA384',
              'ECDHE-ECDSA-AES256-SHA384',
              'ECDHE-RSA-AES256-SHA',
              'ECDHE-ECDSA-AES256-SHA',
              'DHE-RSA-AES128-SHA256',
              'DHE-RSA-AES128-SHA',
              'DHE-DSS-AES128-SHA256',
              'DHE-RSA-AES256-SHA256',
              'DHE-DSS-AES256-SHA',
              'DHE-RSA-AES256-SHA',
              'AES128-GCM-SHA256',
              'AES256-GCM-SHA384',
              'AES128-SHA256',
              'AES256-SHA256',
              'AES128-SHA',
              'AES256-SHA',
              'AES',
              'CAMELLIA',
              'DES-CBC3-SHA',
              '!aNULL',
              '!eNULL',
              '!EXPORT',
              '!DES',
              '!RC4',
              '!MD5',
              '!PSK',
              '!aECDH',
              '!EDH-DSS-DES-CBC3-SHA',
              '!EDH-RSA-DES-CBC3-SHA',
              '!KRB5-DES-CBC3-SHA',
          ));
  
          /**
           * CN_match and SNI_server_name are only known once a URL is passed.
           * They will be set in the getOptionsForUrl() method which receives a URL.
           *
           * cafile or capath can be overridden by passing in those options to constructor.
           */
          $options = array(
              'ssl' => array(
                  'ciphers' => $ciphers,
                  'verify_peer' => true,
                  'verify_depth' => 7,
                  'SNI_enabled' => true,
              )
          );
  
          /**
           * Attempt to find a local cafile or throw an exception.
           * The user may go download one if this occurs.
           */
          if (!$cafile) {
              $cafile = self::getSystemCaRootBundlePath();
          }
          if (is_dir($cafile)) {
              $options['ssl']['capath'] = $cafile;
          } elseif ($cafile) {
              $options['ssl']['cafile'] = $cafile;
          } else {
              throw new RuntimeException('A valid cafile could not be located automatically.');
          }
  
          /**
           * Disable TLS compression to prevent CRIME attacks where supported.
           */
          if (version_compare(PHP_VERSION, '5.4.13') >= 0) {
              $options['ssl']['disable_compression'] = true;
          }
  
          return $options;
      }
  
      /**
       * function copied from Composer\Util\StreamContextFactory::initOptions
       *
       * Any changes should be applied there as well, or backported here.
       *
       * @param string $url URL the context is to be used for
       * @return resource Default context
       * @throws \RuntimeException if https proxy required and OpenSSL uninstalled
       */
      protected function getMergedStreamContext($url)
      {
          $options = $this->options;
  
          // Handle HTTP_PROXY/http_proxy on CLI only for security reasons
          if ((PHP_SAPI === 'cli' || PHP_SAPI === 'phpdbg') && (!empty($_SERVER['HTTP_PROXY']) || !empty($_SERVER['http_proxy']))) {
              $proxy = parse_url(!empty($_SERVER['http_proxy']) ? $_SERVER['http_proxy'] : $_SERVER['HTTP_PROXY']);
          }
  
          // Prefer CGI_HTTP_PROXY if available
          if (!empty($_SERVER['CGI_HTTP_PROXY'])) {
              $proxy = parse_url($_SERVER['CGI_HTTP_PROXY']);
          }
  
          // Override with HTTPS proxy if present and URL is https
          if (preg_match('{^https://}i', $url) && (!empty($_SERVER['HTTPS_PROXY']) || !empty($_SERVER['https_proxy']))) {
              $proxy = parse_url(!empty($_SERVER['https_proxy']) ? $_SERVER['https_proxy'] : $_SERVER['HTTPS_PROXY']);
          }
  
          // Remove proxy if URL matches no_proxy directive
          if (!empty($_SERVER['NO_PROXY']) || !empty($_SERVER['no_proxy']) && parse_url($url, PHP_URL_HOST)) {
              $pattern = new NoProxyPattern(!empty($_SERVER['no_proxy']) ? $_SERVER['no_proxy'] : $_SERVER['NO_PROXY']);
              if ($pattern->test($url)) {
                  unset($proxy);
              }
          }
  
          if (!empty($proxy)) {
              $proxyURL = isset($proxy['scheme']) ? $proxy['scheme'] . '://' : '';
              $proxyURL .= isset($proxy['host']) ? $proxy['host'] : '';
  
              if (isset($proxy['port'])) {
                  $proxyURL .= ":" . $proxy['port'];
              } elseif (strpos($proxyURL, 'http://') === 0) {
                  $proxyURL .= ":80";
              } elseif (strpos($proxyURL, 'https://') === 0) {
                  $proxyURL .= ":443";
              }
  
              // check for a secure proxy
              if (strpos($proxyURL, 'https://') === 0) {
                  if (!extension_loaded('openssl')) {
                      throw new RuntimeException('You must enable the openssl extension to use a secure proxy.');
                  }
                  if (strpos($url, 'https://') === 0) {
                      throw new RuntimeException('PHP does not support https requests through a secure proxy.');
                  }
              }
  
              // http(s):// is not supported in proxy
              $proxyURL = str_replace(array('http://', 'https://'), array('tcp://', 'ssl://'), $proxyURL);
  
              $options['http'] = array(
                  'proxy' => $proxyURL,
              );
  
              // add request_fulluri for http requests
              if ('http' === parse_url($url, PHP_URL_SCHEME)) {
                  $options['http']['request_fulluri'] = true;
              }
  
              // handle proxy auth if present
              if (isset($proxy['user'])) {
                  $auth = rawurldecode($proxy['user']);
                  if (isset($proxy['pass'])) {
                      $auth .= ':' . rawurldecode($proxy['pass']);
                  }
                  $auth = base64_encode($auth);
  
                  $options['http']['header'] = "Proxy-Authorization: Basic {$auth}\r
  ";
              }
          }
  
          if (isset($options['http']['header'])) {
              $options['http']['header'] .= "Connection: close\r
  ";
          } else {
              $options['http']['header'] = "Connection: close\r
  ";
          }
          if (extension_loaded('zlib')) {
              $options['http']['header'] .= "Accept-Encoding: gzip\r
  ";
          }
          $options['http']['header'] .= "User-Agent: ".COMPOSER_INSTALLER."\r
  ";
          $options['http']['protocol_version'] = 1.1;
          $options['http']['timeout'] = 600;
  
          return stream_context_create($options);
      }
  
      /**
      * This method was adapted from Sslurp.
      * https://github.com/EvanDotPro/Sslurp
      *
      * (c) Evan Coury <me@evancoury.com>
      *
      * For the full copyright and license information, please see below:
      *
      * Copyright (c) 2013, Evan Coury
      * All rights reserved.
      *
      * Redistribution and use in source and binary forms, with or without modification,
      * are permitted provided that the following conditions are met:
      *
      *     * Redistributions of source code must retain the above copyright notice,
      *       this list of conditions and the following disclaimer.
      *
      *     * Redistributions in binary form must reproduce the above copyright notice,
      *       this list of conditions and the following disclaimer in the documentation
      *       and/or other materials provided with the distribution.
      *
      * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
      * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
      * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
      * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
      * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
      * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
      * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
      * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
      * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
      * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
      */
      public static function getSystemCaRootBundlePath()
      {
          static $caPath = null;
  
          if ($caPath !== null) {
              return $caPath;
          }
  
          // If SSL_CERT_FILE env variable points to a valid certificate/bundle, use that.
          // This mimics how OpenSSL uses the SSL_CERT_FILE env variable.
          $envCertFile = getenv('SSL_CERT_FILE');
          if ($envCertFile && is_readable($envCertFile) && validateCaFile(file_get_contents($envCertFile))) {
              return $caPath = $envCertFile;
          }
  
          // If SSL_CERT_DIR env variable points to a valid certificate/bundle, use that.
          // This mimics how OpenSSL uses the SSL_CERT_FILE env variable.
          $envCertDir = getenv('SSL_CERT_DIR');
          if ($envCertDir && is_dir($envCertDir) && is_readable($envCertDir)) {
              return $caPath = $envCertDir;
          }
  
          $configured = ini_get('openssl.cafile');
          if ($configured && strlen($configured) > 0 && is_readable($configured) && validateCaFile(file_get_contents($configured))) {
              return $caPath = $configured;
          }
  
          $configured = ini_get('openssl.capath');
          if ($configured && is_dir($configured) && is_readable($configured)) {
              return $caPath = $configured;
          }
  
          $caBundlePaths = array(
              '/etc/pki/tls/certs/ca-bundle.crt', // Fedora, RHEL, CentOS (ca-certificates package)
              '/etc/ssl/certs/ca-certificates.crt', // Debian, Ubuntu, Gentoo, Arch Linux (ca-certificates package)
              '/etc/ssl/ca-bundle.pem', // SUSE, openSUSE (ca-certificates package)
              '/usr/local/share/certs/ca-root-nss.crt', // FreeBSD (ca_root_nss_package)
              '/usr/ssl/certs/ca-bundle.crt', // Cygwin
              '/opt/local/share/curl/curl-ca-bundle.crt', // OS X macports, curl-ca-bundle package
              '/usr/local/share/curl/curl-ca-bundle.crt', // Default cURL CA bunde path (without --with-ca-bundle option)
              '/usr/share/ssl/certs/ca-bundle.crt', // Really old RedHat?
              '/etc/ssl/cert.pem', // OpenBSD
              '/usr/local/etc/ssl/cert.pem', // FreeBSD 10.x
              '/usr/local/etc/openssl/cert.pem', // OS X homebrew, openssl package
              '/usr/local/etc/openssl@1.1/cert.pem', // OS X homebrew, openssl@1.1 package
          );
  
          foreach ($caBundlePaths as $caBundle) {
              if (@is_readable($caBundle) && validateCaFile(file_get_contents($caBundle))) {
                  return $caPath = $caBundle;
              }
          }
  
          foreach ($caBundlePaths as $caBundle) {
              $caBundle = dirname($caBundle);
              if (is_dir($caBundle) && glob($caBundle.'/*')) {
                  return $caPath = $caBundle;
              }
          }
  
          return $caPath = false;
      }
  
      public static function getPackagedCaFile()
      {
          return <<<CACERT
  ##
  ## Bundle of CA Root Certificates for Let's Encrypt
  ##
  ## See https://letsencrypt.org/certificates/#root-certificates
  ##
  ## ISRG Root X1 (RSA 4096) expires Jun 04 11:04:38 2035 GMT
  ## ISRG Root X2 (ECDSA P-384) expires Sep 17 16:00:00 2040 GMT
  ##
  ## Both these are self-signed CA root certificates
  ##
  
  ISRG Root X1
  ============
  -----BEGIN CERTIFICATE-----
  MIIFazCCA1OgAwIBAgIRAIIQz7DSQONZRGPgu2OCiwAwDQYJKoZIhvcNAQELBQAw
  TzELMAkGA1UEBhMCVVMxKTAnBgNVBAoTIEludGVybmV0IFNlY3VyaXR5IFJlc2Vh
  cmNoIEdyb3VwMRUwEwYDVQQDEwxJU1JHIFJvb3QgWDEwHhcNMTUwNjA0MTEwNDM4
  WhcNMzUwNjA0MTEwNDM4WjBPMQswCQYDVQQGEwJVUzEpMCcGA1UEChMgSW50ZXJu
  ZXQgU2VjdXJpdHkgUmVzZWFyY2ggR3JvdXAxFTATBgNVBAMTDElTUkcgUm9vdCBY
  MTCCAiIwDQYJKoZIhvcNAQEBBQADggIPADCCAgoCggIBAK3oJHP0FDfzm54rVygc
  h77ct984kIxuPOZXoHj3dcKi/vVqbvYATyjb3miGbESTtrFj/RQSa78f0uoxmyF+
  0TM8ukj13Xnfs7j/EvEhmkvBioZxaUpmZmyPfjxwv60pIgbz5MDmgK7iS4+3mX6U
  A5/TR5d8mUgjU+g4rk8Kb4Mu0UlXjIB0ttov0DiNewNwIRt18jA8+o+u3dpjq+sW
  T8KOEUt+zwvo/7V3LvSye0rgTBIlDHCNAymg4VMk7BPZ7hm/ELNKjD+Jo2FR3qyH
  B5T0Y3HsLuJvW5iB4YlcNHlsdu87kGJ55tukmi8mxdAQ4Q7e2RCOFvu396j3x+UC
  B5iPNgiV5+I3lg02dZ77DnKxHZu8A/lJBdiB3QW0KtZB6awBdpUKD9jf1b0SHzUv
  KBds0pjBqAlkd25HN7rOrFleaJ1/ctaJxQZBKT5ZPt0m9STJEadao0xAH0ahmbWn
  OlFuhjuefXKnEgV4We0+UXgVCwOPjdAvBbI+e0ocS3MFEvzG6uBQE3xDk3SzynTn
  jh8BCNAw1FtxNrQHusEwMFxIt4I7mKZ9YIqioymCzLq9gwQbooMDQaHWBfEbwrbw
  qHyGO0aoSCqI3Haadr8faqU9GY/rOPNk3sgrDQoo//fb4hVC1CLQJ13hef4Y53CI
  rU7m2Ys6xt0nUW7/vGT1M0NPAgMBAAGjQjBAMA4GA1UdDwEB/wQEAwIBBjAPBgNV
  HRMBAf8EBTADAQH/MB0GA1UdDgQWBBR5tFnme7bl5AFzgAiIyBpY9umbbjANBgkq
  hkiG9w0BAQsFAAOCAgEAVR9YqbyyqFDQDLHYGmkgJykIrGF1XIpu+ILlaS/V9lZL
  ubhzEFnTIZd+50xx+7LSYK05qAvqFyFWhfFQDlnrzuBZ6brJFe+GnY+EgPbk6ZGQ
  3BebYhtF8GaV0nxvwuo77x/Py9auJ/GpsMiu/X1+mvoiBOv/2X/qkSsisRcOj/KK
  NFtY2PwByVS5uCbMiogziUwthDyC3+6WVwW6LLv3xLfHTjuCvjHIInNzktHCgKQ5
  ORAzI4JMPJ+GslWYHb4phowim57iaztXOoJwTdwJx4nLCgdNbOhdjsnvzqvHu7Ur
  TkXWStAmzOVyyghqpZXjFaH3pO3JLF+l+/+sKAIuvtd7u+Nxe5AW0wdeRlN8NwdC
  jNPElpzVmbUq4JUagEiuTDkHzsxHpFKVK7q4+63SM1N95R1NbdWhscdCb+ZAJzVc
  oyi3B43njTOQ5yOf+1CceWxG1bQVs5ZufpsMljq4Ui0/1lvh+wjChP4kqKOJ2qxq
  4RgqsahDYVvTH9w7jXbyLeiNdd8XM2w9U/t7y0Ff/9yi0GE44Za4rF2LN9d11TPA
  mRGunUHBcnWEvgJBQl9nJEiU0Zsnvgc/ubhPgXRR4Xq37Z0j4r7g1SgEEzwxA57d
  emyPxgcYxn/eR44/KJ4EBs+lVDR3veyJm+kXQ99b21/+jh5Xos1AnX5iItreGCc=
  -----END CERTIFICATE-----
  
  ISRG Root X2
  ============
  -----BEGIN CERTIFICATE-----
  MIICGzCCAaGgAwIBAgIQQdKd0XLq7qeAwSxs6S+HUjAKBggqhkjOPQQDAzBPMQsw
  CQYDVQQGEwJVUzEpMCcGA1UEChMgSW50ZXJuZXQgU2VjdXJpdHkgUmVzZWFyY2gg
  R3JvdXAxFTATBgNVBAMTDElTUkcgUm9vdCBYMjAeFw0yMDA5MDQwMDAwMDBaFw00
  MDA5MTcxNjAwMDBaME8xCzAJBgNVBAYTAlVTMSkwJwYDVQQKEyBJbnRlcm5ldCBT
  ZWN1cml0eSBSZXNlYXJjaCBHcm91cDEVMBMGA1UEAxMMSVNSRyBSb290IFgyMHYw
  EAYHKoZIzj0CAQYFK4EEACIDYgAEzZvVn4CDCuwJSvMWSj5cz3es3mcFDR0HttwW
  +1qLFNvicWDEukWVEYmO6gbf9yoWHKS5xcUy4APgHoIYOIvXRdgKam7mAHf7AlF9
  ItgKbppbd9/w+kHsOdx1ymgHDB/qo0IwQDAOBgNVHQ8BAf8EBAMCAQYwDwYDVR0T
  AQH/BAUwAwEB/zAdBgNVHQ4EFgQUfEKWrt5LSDv6kviejM9ti6lyN5UwCgYIKoZI
  zj0EAwMDaAAwZQIwe3lORlCEwkSHRhtFcP9Ymd70/aTSVaYgLXTWNLxBo1BfASdW
  tL4ndQavEi51mI38AjEAi/V3bNTIZargCyzuFJ0nN6T5U6VR5CmD1/iQMVtCnwr1
  /q4AaOeMSQ+2b1tbFfLn
  -----END CERTIFICATE-----
  CACERT;
      }
  }