# tablepress/2.2.4/libraries/freemius/includes/fs-essential-functions.php

TablePress – Tables in WordPress made easy, version 2.2.4. 418 lines.

- Page: https://pluginprobe.com/plugins/tablepress/2.2.4/code/libraries/freemius/includes/fs-essential-functions.php
- Raw: https://pluginprobe.com/plugins/tablepress/2.2.4/raw/libraries/freemius/includes/fs-essential-functions.php
- Modified: 2023-11-02T08:57:02+00:00

Line numbers below start at 1. Link to a line or a range by appending a fragment to the
page URL, for example `https://pluginprobe.com/plugins/tablepress/2.2.4/code/libraries/freemius/includes/fs-essential-functions.php#L10-L20`.

```php
<?php
	/**
	 * IMPORTANT:
	 *      This file will be loaded based on the order of the plugins/themes load.
	 *      If there's a theme and a plugin using Freemius, the plugin's essential
	 *      file will always load first.
	 *
	 * @package     Freemius
	 * @copyright   Copyright (c) 2015, Freemius, Inc.
	 * @license     https://www.gnu.org/licenses/gpl-3.0.html GNU General Public License Version 3
	 * @since       1.1.5
	 */

	if ( ! function_exists( 'fs_normalize_path' ) ) {
		if ( function_exists( 'wp_normalize_path' ) ) {
			/**
			 * Normalize a filesystem path.
			 *
			 * Replaces backslashes with forward slashes for Windows systems, and ensures
			 * no duplicate slashes exist.
			 *
			 * @param string $path Path to normalize.
			 *
			 * @return string Normalized path.
			 */
			function fs_normalize_path( $path ) {
				return wp_normalize_path( $path );
			}
		} else {
			function fs_normalize_path( $path ) {
				$path = str_replace( '\\', '/', $path );
				$path = preg_replace( '|/+|', '/', $path );

				return $path;
			}
		}
	}

	require_once dirname( __FILE__ ) . '/supplements/fs-essential-functions-2.2.1.php';

	#region Core Redirect (copied from BuddyPress) -----------------------------------------

	if ( ! function_exists( 'fs_redirect' ) ) {
		/**
		 * Redirects to another page, with a workaround for the IIS Set-Cookie bug.
		 *
		 * @link  http://support.microsoft.com/kb/q176113/
		 * @since 1.5.1
		 * @uses  apply_filters() Calls 'wp_redirect' hook on $location and $status.
		 *
		 * @param string $location The path to redirect to.
		 * @param bool   $exit     If true, exit after redirect (Since 1.2.1.5).
		 * @param int    $status   Status code to use.
		 *
		 * @return bool False if $location is not set
		 */
		function fs_redirect( $location, $exit = true, $status = 302 ) {
			global $is_IIS;

			$file = '';
			$line = '';
			if ( headers_sent($file, $line) ) {
				if ( WP_FS__DEBUG_SDK && class_exists( 'FS_Admin_Notices' ) ) {
					$notices = FS_Admin_Notices::instance( 'global' );

					$notices->add( "Freemius failed to redirect the page because the headers have been already sent from line <b><code>{$line}</code></b> in file <b><code>{$file}</code></b>. If it's unexpected, it usually happens due to invalid space and/or EOL character(s).", 'Oops...', 'error' );
				}

				return false;
			}

			if ( defined( 'DOING_AJAX' ) ) {
				// Don't redirect on AJAX calls.
				return false;
			}

			if ( ! $location ) // allows the wp_redirect filter to cancel a redirect
			{
				return false;
			}

			$location = fs_sanitize_redirect( $location );

			if ( $is_IIS ) {
				header( "Refresh: 0;url=$location" );
			} else {
				if ( php_sapi_name() != 'cgi-fcgi' ) {
					status_header( $status );
				} // This causes problems on IIS and some FastCGI setups
				header( "Location: $location" );
			}

			if ( $exit ) {
				exit();
			}

			return true;
		}

		if ( ! function_exists( 'fs_sanitize_redirect' ) ) {
			/**
			 * Sanitizes a URL for use in a redirect.
			 *
			 * @since 2.3
			 *
			 * @param string $location
			 *
			 * @return string redirect-sanitized URL
			 */
			function fs_sanitize_redirect( $location ) {
				$location = preg_replace( '|[^a-z0-9-~+_.?#=&;,/:%!]|i', '', $location );
				$location = fs_kses_no_null( $location );

				// remove %0d and %0a from location
				$strip = array( '%0d', '%0a' );
				$found = true;
				while ( $found ) {
					$found = false;
					foreach ( (array) $strip as $val ) {
						while ( strpos( $location, $val ) !== false ) {
							$found    = true;
							$location = str_replace( $val, '', $location );
						}
					}
				}

				return $location;
			}
		}

		if ( ! function_exists( 'fs_kses_no_null' ) ) {
			/**
			 * Removes any NULL characters in $string.
			 *
			 * @since 1.0.0
			 *
			 * @param string $string
			 *
			 * @return string
			 */
			function fs_kses_no_null( $string ) {
				$string = preg_replace( '/\0+/', '', $string );
				$string = preg_replace( '/(\\\\0)+/', '', $string );

				return $string;
			}
		}
	}

	#endregion Core Redirect (copied from BuddyPress) -----------------------------------------

	if ( ! function_exists( 'fs_get_ip' ) ) {
		/**
		 * Get server IP.
		 *
		 * @since 2.5.1 This method returns the server IP.
		 *
		 * @author Vova Feldman (@svovaf)
		 * @since  1.1.2
		 *
		 * @return string|null
		 */
		function fs_get_ip() {
			return empty( $_SERVER[ 'SERVER_ADDR' ] ) ?
				null :
				$_SERVER[ 'SERVER_ADDR' ];
		}
	}

	if ( ! function_exists( 'fs_find_caller_plugin_file' ) ) {
		/**
		 * Leverage backtrace to find caller plugin main file path.
		 *
	     * @author Vova Feldman (@svovaf)
		 * @since  1.0.6
		 *
	     * @return string
		 */
		function fs_find_caller_plugin_file() {
			/**
			 * All the code below will be executed once on activation.
			 * If the user changes the main plugin's file name, the file_exists()
			 * will catch it.
			 */
			if ( ! function_exists( 'get_plugins' ) ) {
				require_once ABSPATH . 'wp-admin/includes/plugin.php';
			}

			$all_plugins       = fs_get_plugins( true );
			$all_plugins_paths = array();

			// Get active plugin's main files real full names (might be symlinks).
			foreach ( $all_plugins as $relative_path => $data ) {
				$all_plugins_paths[] = fs_normalize_path( realpath( WP_PLUGIN_DIR . '/' . $relative_path ) );
			}

			$plugin_file = null;
			for ( $i = 1, $bt = debug_backtrace(), $len = count( $bt ); $i < $len; $i ++ ) {
				if ( empty( $bt[ $i ]['file'] ) ) {
					continue;
				}

				if ( in_array( fs_normalize_path( $bt[ $i ]['file'] ), $all_plugins_paths ) ) {
					$plugin_file = $bt[ $i ]['file'];
					break;
				}
			}

			if ( is_null( $plugin_file ) ) {
				// Throw an error to the developer in case of some edge case dev environment.
				wp_die(
					'Freemius SDK couldn\'t find the plugin\'s main file. Please contact sdk@freemius.com with the current error.',
					'Error',
					array( 'back_link' => true )
				);
			}

			return $plugin_file;
		}
	}

	require_once dirname( __FILE__ ) . '/supplements/fs-essential-functions-1.1.7.1.php';

	if ( ! function_exists( 'fs_update_sdk_newest_version' ) ) {
		/**
		 * Update SDK newest version reference.
		 *
		 * @author Vova Feldman (@svovaf)
		 * @since  1.1.6
		 *
		 * @param string      $sdk_relative_path
		 * @param string|bool $plugin_file
		 *
		 * @global            $fs_active_plugins
		 */
		function fs_update_sdk_newest_version( $sdk_relative_path, $plugin_file = false ) {
			/**
			 * If there is a plugin running an older version of FS (1.2.1 or below), the `fs_update_sdk_newest_version()`
			 * function in the older version will be used instead of this one. But since the older version is using
			 * the `is_plugin_active` function to check if a plugin is active, passing the theme's `plugin_path` to the
			 * `is_plugin_active` function will return false since the path is not a plugin path, so `in_activation` will be
			 * `true` for theme modules and the upgrading of the SDK version to 1.2.2 or newer version will work fine.
			 *
			 * Future versions that will call this function will use the proper logic here instead of just relying on the
			 * `is_plugin_active` function to fail for themes.
			 *
			 * @author Leo Fajardo (@leorw)
			 * @since  1.2.2
			 */

			global $fs_active_plugins;

			$newest_sdk = $fs_active_plugins->plugins[ $sdk_relative_path ];

			if ( ! is_string( $plugin_file ) ) {
				$plugin_file = plugin_basename( fs_find_caller_plugin_file() );
			}

			if ( ! isset( $newest_sdk->type ) || 'theme' !== $newest_sdk->type ) {
				if ( ! function_exists( 'is_plugin_active' ) ) {
					require_once ABSPATH . 'wp-admin/includes/plugin.php';
				}

				$in_activation = ( ! is_plugin_active( $plugin_file ) );
			} else {
				$theme         = wp_get_theme();
				$in_activation = ( $newest_sdk->plugin_path == $theme->stylesheet );
			}

			$fs_active_plugins->newest = (object) array(
				'plugin_path'   => $plugin_file,
				'sdk_path'      => $sdk_relative_path,
				'version'       => $newest_sdk->version,
				'in_activation' => $in_activation,
				'timestamp'     => time(),
			);

			// Update DB with latest SDK version and path.
			update_option( 'fs_active_plugins', $fs_active_plugins );
		}
	}

	if ( ! function_exists( 'fs_newest_sdk_plugin_first' ) ) {
		/**
		 * Reorder the plugins load order so the plugin with the newest Freemius SDK is loaded first.
		 *
		 * @author Vova Feldman (@svovaf)
		 * @since  1.1.6
		 *
		 * @return bool Was plugin order changed. Return false if plugin was loaded first anyways.
		 *
		 * @global $fs_active_plugins
		 */
		function fs_newest_sdk_plugin_first() {
			global $fs_active_plugins;

			/**
			 * @todo Multi-site network activated plugin are always loaded prior to site plugins so if there's a plugin activated in the network mode that has an older version of the SDK of another plugin which is site activated that has new SDK version, the fs-essential-functions.php will be loaded from the older SDK. Same thing about MU plugins (loaded even before network activated plugins).
			 *
			 * @link https://github.com/Freemius/wordpress-sdk/issues/26
			 */

			$newest_sdk_plugin_path = $fs_active_plugins->newest->plugin_path;

			$active_plugins         = get_option( 'active_plugins', array() );
			$updated_active_plugins = array( $newest_sdk_plugin_path );

			$plugin_found  = false;
			$is_first_path = true;

			foreach ( $active_plugins as $key => $plugin_path ) {
				if ( $plugin_path === $newest_sdk_plugin_path ) {
					if ( $is_first_path ) {
						// if it's the first plugin already, no need to continue
						return false;
					}

					$plugin_found = true;

					// Skip the plugin (it is already added as the 1st item of $updated_active_plugins).
					continue;
				}

				$updated_active_plugins[] = $plugin_path;

				if ( $is_first_path ) {
					$is_first_path = false;
				}
			}

			if ( $plugin_found ) {
				update_option( 'active_plugins', $updated_active_plugins );

				return true;
			}

			if ( is_multisite() ) {
				// Plugin is network active.
				$network_active_plugins = get_site_option( 'active_sitewide_plugins', array() );

				if ( isset( $network_active_plugins[ $newest_sdk_plugin_path ] ) ) {
					reset( $network_active_plugins );
					if ( $newest_sdk_plugin_path === key( $network_active_plugins ) ) {
						// Plugin is already activated first on the network level.
						return false;
					} else {
						$time = $network_active_plugins[ $newest_sdk_plugin_path ];

						// Remove plugin from its current position.
						unset( $network_active_plugins[ $newest_sdk_plugin_path ] );

						// Set it to be included first.
						$network_active_plugins = array( $newest_sdk_plugin_path => $time ) + $network_active_plugins;

						update_site_option( 'active_sitewide_plugins', $network_active_plugins );

						return true;
					}
				}
			}

			return false;
		}
	}

	if ( ! function_exists( 'fs_fallback_to_newest_active_sdk' ) ) {
		/**
		 * Go over all Freemius SDKs in the system and find and "remember"
		 * the newest SDK which is associated with an active plugin.
		 *
		 * @author Vova Feldman (@svovaf)
		 * @since  1.1.6
		 *
		 * @global $fs_active_plugins
		 */
		function fs_fallback_to_newest_active_sdk() {
			global $fs_active_plugins;

			/**
			 * @var object $newest_sdk_data
			 */
			$newest_sdk_data = null;
			$newest_sdk_path = null;

			foreach ( $fs_active_plugins->plugins as $sdk_relative_path => $data ) {
				if ( is_null( $newest_sdk_data ) || version_compare( $data->version, $newest_sdk_data->version, '>' )
				) {
					// If plugin inactive or SDK starter file doesn't exist, remove SDK reference.
					if ( 'plugin' === $data->type ) {
						$is_module_active = is_plugin_active( $data->plugin_path );
					} else {
						$active_theme     = wp_get_theme();
						$is_module_active = ( $data->plugin_path === $active_theme->get_template() );
					}

					$is_sdk_exists = file_exists( fs_normalize_path( WP_PLUGIN_DIR . '/' . $sdk_relative_path . '/start.php' ) );

					if ( ! $is_module_active || ! $is_sdk_exists ) {
						unset( $fs_active_plugins->plugins[ $sdk_relative_path ] );

						// No need to store the data since it will be stored in fs_update_sdk_newest_version()
						// or explicitly with update_option().
					} else {
						$newest_sdk_data = $data;
						$newest_sdk_path = $sdk_relative_path;
					}
				}
			}

			if ( is_null( $newest_sdk_data ) ) {
				// Couldn't find any SDK reference.
				$fs_active_plugins = new stdClass();
				update_option( 'fs_active_plugins', $fs_active_plugins );
			} else {
				fs_update_sdk_newest_version( $newest_sdk_path, $newest_sdk_data->plugin_path );
			}
		}
	}
```