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<?php

/**
 * WordPress Administration Bootstrap
 *
 * @package WordPress
 * @subpackage Administration
 */


/**
 * In WordPress Administration Screens
 *
 * @since 2.3.2
 */
if ( ! defined( 'WP_ADMIN' ) ) {
  define( 'WP_ADMIN', true );
}

if ( ! defined( 'WP_NETWORK_ADMIN' ) ) {
  define( 'WP_NETWORK_ADMIN', false );
}

if ( ! defined( 'WP_USER_ADMIN' ) ) {
  define( 'WP_USER_ADMIN', false );
}

if ( ! WP_NETWORK_ADMIN && ! WP_USER_ADMIN ) {
  define( 'WP_BLOG_ADMIN', true );
}

if ( isset( $_GET['import'] ) && ! defined( 'WP_LOAD_IMPORTERS' ) ) {
  define( 'WP_LOAD_IMPORTERS', true );
}

require_once dirname( __DIR__ ) . '/wp-load.php';

nocache_headers();

if ( get_option( 'db_upgraded' ) ) {

  flush_rewrite_rules();
  update_option( 'db_upgraded', false );

  
/**
 * Fires on the next page load after a successful DB upgrade.
 *
 * @since 2.8.0
 */
  do_action( 'after_db_upgrade' );

} elseif ( ! wp_doing_ajax() && empty( $_POST )
  && (int) get_option( 'db_version' ) !== $wp_db_version
) {

  if ( ! is_multisite() ) {
    wp_redirect( admin_url( 'upgrade.php?_wp_http_referer=' . urlencode( wp_unslash( $_SERVER['REQUEST_URI'] ) ) ) );
    exit;
  }

  
/**
 * Filters whether to attempt to perform the multisite DB upgrade routine.
 *
 * In single site, the user would be redirected to wp-admin/upgrade.php.
 * In multisite, the DB upgrade routine is automatically fired, but only
 * when this filter returns true.
 *
 * If the network is 50 sites or less, it will run every time. Otherwise,
 * it will throttle itTelf to reduce load.
 *
 * @since MU (3.0.0)
 *
 * @param bool $do_mu_upgrade Whether to perform the Multisite upgrade routine. Default true.
 */
  if ( apply_filters( 'do_mu_upgrade', true ) ) {
    $c = get_blog_count();

    /*
		 * If there are 50 or fewer sites, run every time. Otherwise, throttle to reduce load:
		 * attempt to do no more than threshold value, with some +/- allowed.
		 */
    if ( $c <= 50 || ( $c > 50 && mt_rand( 0, (int) ( $c / 50 ) ) === 1 ) ) {
      require_once ABSPATH . WPINC . '/http.php';
      $response = wp_remote_get(
        admin_url( 'upgrade.php?step=1' ),
        array(
          'timeout'     => 120,
          'httpversion' => '1.1',
        )
      );
      
/** This action is documented in wp-admin/network/upgrade.php */
      do_action( 'after_mu_upgrade', $response );
      unset( $response );
    }
    unset( $c );
  }
}

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