class-wp-filesystem-base.php 22.8 KB
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<?php
/**
 * Base WordPress Filesystem
 *
 * @package WordPress
 * @subpackage Filesystem
 */

/**
 * Base WordPress Filesystem class which Filesystem implementations extend.
 *
 * @since 2.5.0
 */
class WP_Filesystem_Base {

	/**
	 * Whether to display debug data for the connection.
	 *
	 * @since 2.5.0
	 * @var bool
	 */
	public $verbose = false;

	/**
	 * Cached list of local filepaths to mapped remote filepaths.
	 *
	 * @since 2.7.0
	 * @var array
	 */
	public $cache = array();

	/**
	 * The Access method of the current connection, Set automatically.
	 *
	 * @since 2.5.0
	 * @var string
	 */
	public $method = '';

	/**
	 * @var WP_Error
	 */
	public $errors = null;

	/**
	 */
	public $options = array();

	/**
	 * Returns the path on the remote filesystem of ABSPATH.
	 *
	 * @since 2.7.0
	 *
	 * @return string The location of the remote path.
	 */
	public function abspath() {
		$folder = $this->find_folder( ABSPATH );

		// Perhaps the FTP folder is rooted at the WordPress install.
		// Check for wp-includes folder in root. Could have some false positives, but rare.
		if ( ! $folder && $this->is_dir( '/' . WPINC ) ) {
			$folder = '/';
		}

		return $folder;
	}

	/**
	 * Returns the path on the remote filesystem of WP_CONTENT_DIR.
	 *
	 * @since 2.7.0
	 *
	 * @return string The location of the remote path.
	 */
	public function wp_content_dir() {
		return $this->find_folder( WP_CONTENT_DIR );
	}

	/**
	 * Returns the path on the remote filesystem of WP_PLUGIN_DIR.
	 *
	 * @since 2.7.0
	 *
	 * @return string The location of the remote path.
	 */
	public function wp_plugins_dir() {
		return $this->find_folder( WP_PLUGIN_DIR );
	}

	/**
	 * Returns the path on the remote filesystem of the Themes Directory.
	 *
	 * @since 2.7.0
	 *
	 * @param string|false $theme Optional. The theme stylesheet or template for the directory.
	 *                            Default false.
	 * @return string The location of the remote path.
	 */
	public function wp_themes_dir( $theme = false ) {
		$theme_root = get_theme_root( $theme );

		// Account for relative theme roots.
		if ( '/themes' === $theme_root || ! is_dir( $theme_root ) ) {
			$theme_root = WP_CONTENT_DIR . $theme_root;
		}

		return $this->find_folder( $theme_root );
	}

	/**
	 * Returns the path on the remote filesystem of WP_LANG_DIR.
	 *
	 * @since 3.2.0
	 *
	 * @return string The location of the remote path.
	 */
	public function wp_lang_dir() {
		return $this->find_folder( WP_LANG_DIR );
	}

	/**
	 * Locates a folder on the remote filesystem.
	 *
	 * @since 2.5.0
	 * @deprecated 2.7.0 use WP_Filesystem_Base::abspath() or WP_Filesystem_Base::wp_*_dir() instead.
	 * @see WP_Filesystem_Base::abspath()
	 * @see WP_Filesystem_Base::wp_content_dir()
	 * @see WP_Filesystem_Base::wp_plugins_dir()
	 * @see WP_Filesystem_Base::wp_themes_dir()
	 * @see WP_Filesystem_Base::wp_lang_dir()
	 *
	 * @param string $base    Optional. The folder to start searching from. Default '.'.
	 * @param bool   $verbose Optional. True to display debug information. Default false.
	 * @return string The location of the remote path.
	 */
	public function find_base_dir( $base = '.', $verbose = false ) {
		_deprecated_function( __FUNCTION__, '2.7.0', 'WP_Filesystem_Base::abspath() or WP_Filesystem_Base::wp_*_dir()' );
		$this->verbose = $verbose;
		return $this->abspath();
	}

	/**
	 * Locates a folder on the remote filesystem.
	 *
	 * @since 2.5.0
	 * @deprecated 2.7.0 use WP_Filesystem_Base::abspath() or WP_Filesystem_Base::wp_*_dir() methods instead.
	 * @see WP_Filesystem_Base::abspath()
	 * @see WP_Filesystem_Base::wp_content_dir()
	 * @see WP_Filesystem_Base::wp_plugins_dir()
	 * @see WP_Filesystem_Base::wp_themes_dir()
	 * @see WP_Filesystem_Base::wp_lang_dir()
	 *
	 * @param string $base    Optional. The folder to start searching from. Default '.'.
	 * @param bool   $verbose Optional. True to display debug information. Default false.
	 * @return string The location of the remote path.
	 */
	public function get_base_dir( $base = '.', $verbose = false ) {
		_deprecated_function( __FUNCTION__, '2.7.0', 'WP_Filesystem_Base::abspath() or WP_Filesystem_Base::wp_*_dir()' );
		$this->verbose = $verbose;
		return $this->abspath();
	}

	/**
	 * Locates a folder on the remote filesystem.
	 *
	 * Assumes that on Windows systems, Stripping off the Drive
	 * letter is OK Sanitizes \\ to / in Windows filepaths.
	 *
	 * @since 2.7.0
	 *
	 * @param string $folder the folder to locate.
	 * @return string|false The location of the remote path, false on failure.
	 */
	public function find_folder( $folder ) {
		if ( isset( $this->cache[ $folder ] ) ) {
			return $this->cache[ $folder ];
		}

		if ( stripos( $this->method, 'ftp' ) !== false ) {
			$constant_overrides = array(
				'FTP_BASE'        => ABSPATH,
				'FTP_CONTENT_DIR' => WP_CONTENT_DIR,
				'FTP_PLUGIN_DIR'  => WP_PLUGIN_DIR,
				'FTP_LANG_DIR'    => WP_LANG_DIR,
			);

			// Direct matches ( folder = CONSTANT/ ).
			foreach ( $constant_overrides as $constant => $dir ) {
				if ( ! defined( $constant ) ) {
					continue;
				}

				if ( $folder === $dir ) {
					return trailingslashit( constant( $constant ) );
				}
			}

			// Prefix matches ( folder = CONSTANT/subdir ),
			foreach ( $constant_overrides as $constant => $dir ) {
				if ( ! defined( $constant ) ) {
					continue;
				}

				if ( 0 === stripos( $folder, $dir ) ) { // $folder starts with $dir.
					$potential_folder = preg_replace( '#^' . preg_quote( $dir, '#' ) . '/#i', trailingslashit( constant( $constant ) ), $folder );
					$potential_folder = trailingslashit( $potential_folder );

					if ( $this->is_dir( $potential_folder ) ) {
						$this->cache[ $folder ] = $potential_folder;

						return $potential_folder;
					}
				}
			}
		} elseif ( 'direct' === $this->method ) {
			$folder = str_replace( '\\', '/', $folder ); // Windows path sanitisation.

			return trailingslashit( $folder );
		}

		$folder = preg_replace( '|^([a-z]{1}):|i', '', $folder ); // Strip out Windows drive letter if it's there.
		$folder = str_replace( '\\', '/', $folder ); // Windows path sanitisation.

		if ( isset( $this->cache[ $folder ] ) ) {
			return $this->cache[ $folder ];
		}

		if ( $this->exists( $folder ) ) { // Folder exists at that absolute path.
			$folder                 = trailingslashit( $folder );
			$this->cache[ $folder ] = $folder;

			return $folder;
		}

		$return = $this->search_for_folder( $folder );

		if ( $return ) {
			$this->cache[ $folder ] = $return;
		}

		return $return;
	}

	/**
	 * Locates a folder on the remote filesystem.
	 *
	 * Expects Windows sanitized path.
	 *
	 * @since 2.7.0
	 *
	 * @param string $folder The folder to locate.
	 * @param string $base   The folder to start searching from.
	 * @param bool   $loop   If the function has recursed. Internal use only.
	 * @return string|false The location of the remote path, false to cease looping.
	 */
	public function search_for_folder( $folder, $base = '.', $loop = false ) {
		if ( empty( $base ) || '.' === $base ) {
			$base = trailingslashit( $this->cwd() );
		}

		$folder = untrailingslashit( $folder );

		if ( $this->verbose ) {
			/* translators: 1: Folder to locate, 2: Folder to start searching from. */
			printf( "\n" . __( 'Looking for %1$s in %2$s' ) . "<br/>\n", $folder, $base );
		}

		$folder_parts     = explode( '/', $folder );
		$folder_part_keys = array_keys( $folder_parts );
		$last_index       = array_pop( $folder_part_keys );
		$last_path        = $folder_parts[ $last_index ];

		$files = $this->dirlist( $base );

		foreach ( $folder_parts as $index => $key ) {
			if ( $index === $last_index ) {
				continue; // We want this to be caught by the next code block.
			}

			/*
			 * Working from /home/ to /user/ to /wordpress/ see if that file exists within
			 * the current folder, If it's found, change into it and follow through looking
			 * for it. If it can't find WordPress down that route, it'll continue onto the next
			 * folder level, and see if that matches, and so on. If it reaches the end, and still
			 * can't find it, it'll return false for the entire function.
			 */
			if ( isset( $files[ $key ] ) ) {

				// Let's try that folder:
				$newdir = trailingslashit( path_join( $base, $key ) );

				if ( $this->verbose ) {
					/* translators: %s: Directory name. */
					printf( "\n" . __( 'Changing to %s' ) . "<br/>\n", $newdir );
				}

				// Only search for the remaining path tokens in the directory, not the full path again.
				$newfolder = implode( '/', array_slice( $folder_parts, $index + 1 ) );
				$ret       = $this->search_for_folder( $newfolder, $newdir, $loop );

				if ( $ret ) {
					return $ret;
				}
			}
		}

		// Only check this as a last resort, to prevent locating the incorrect install.
		// All above procedures will fail quickly if this is the right branch to take.
		if ( isset( $files[ $last_path ] ) ) {
			if ( $this->verbose ) {
				/* translators: %s: Directory name. */
				printf( "\n" . __( 'Found %s' ) . "<br/>\n", $base . $last_path );
			}

			return trailingslashit( $base . $last_path );
		}

		// Prevent this function from looping again.
		// No need to proceed if we've just searched in `/`.
		if ( $loop || '/' === $base ) {
			return false;
		}

		// As an extra last resort, Change back to / if the folder wasn't found.
		// This comes into effect when the CWD is /home/user/ but WP is at /var/www/....
		return $this->search_for_folder( $folder, '/', true );

	}

	/**
	 * Returns the *nix-style file permissions for a file.
	 *
	 * From the PHP documentation page for fileperms().
	 *
	 * @link https://www.php.net/manual/en/function.fileperms.php
	 *
	 * @since 2.5.0
	 *
	 * @param string $file String filename.
	 * @return string The *nix-style representation of permissions.
	 */
	public function gethchmod( $file ) {
		$perms = intval( $this->getchmod( $file ), 8 );

		if ( ( $perms & 0xC000 ) === 0xC000 ) { // Socket.
			$info = 's';
		} elseif ( ( $perms & 0xA000 ) === 0xA000 ) { // Symbolic Link.
			$info = 'l';
		} elseif ( ( $perms & 0x8000 ) === 0x8000 ) { // Regular.
			$info = '-';
		} elseif ( ( $perms & 0x6000 ) === 0x6000 ) { // Block special.
			$info = 'b';
		} elseif ( ( $perms & 0x4000 ) === 0x4000 ) { // Directory.
			$info = 'd';
		} elseif ( ( $perms & 0x2000 ) === 0x2000 ) { // Character special.
			$info = 'c';
		} elseif ( ( $perms & 0x1000 ) === 0x1000 ) { // FIFO pipe.
			$info = 'p';
		} else { // Unknown.
			$info = 'u';
		}

		// Owner.
		$info .= ( ( $perms & 0x0100 ) ? 'r' : '-' );
		$info .= ( ( $perms & 0x0080 ) ? 'w' : '-' );
		$info .= ( ( $perms & 0x0040 ) ?
					( ( $perms & 0x0800 ) ? 's' : 'x' ) :
					( ( $perms & 0x0800 ) ? 'S' : '-' ) );

		// Group.
		$info .= ( ( $perms & 0x0020 ) ? 'r' : '-' );
		$info .= ( ( $perms & 0x0010 ) ? 'w' : '-' );
		$info .= ( ( $perms & 0x0008 ) ?
					( ( $perms & 0x0400 ) ? 's' : 'x' ) :
					( ( $perms & 0x0400 ) ? 'S' : '-' ) );

		// World.
		$info .= ( ( $perms & 0x0004 ) ? 'r' : '-' );
		$info .= ( ( $perms & 0x0002 ) ? 'w' : '-' );
		$info .= ( ( $perms & 0x0001 ) ?
					( ( $perms & 0x0200 ) ? 't' : 'x' ) :
					( ( $perms & 0x0200 ) ? 'T' : '-' ) );

		return $info;
	}

	/**
	 * Gets the permissions of the specified file or filepath in their octal format.
	 *
	 * @since 2.5.0
	 *
	 * @param string $file Path to the file.
	 * @return string Mode of the file (the last 3 digits).
	 */
	public function getchmod( $file ) {
		return '777';
	}

	/**
	 * Converts *nix-style file permissions to a octal number.
	 *
	 * Converts '-rw-r--r--' to 0644
	 * From "info at rvgate dot nl"'s comment on the PHP documentation for chmod()
	 *
	 * @link https://www.php.net/manual/en/function.chmod.php#49614
	 *
	 * @since 2.5.0
	 *
	 * @param string $mode string The *nix-style file permissions.
	 * @return string Octal representation of permissions.
	 */
	public function getnumchmodfromh( $mode ) {
		$realmode = '';
		$legal    = array( '', 'w', 'r', 'x', '-' );
		$attarray = preg_split( '//', $mode );

		for ( $i = 0, $c = count( $attarray ); $i < $c; $i++ ) {
			$key = array_search( $attarray[ $i ], $legal, true );

			if ( $key ) {
				$realmode .= $legal[ $key ];
			}
		}

		$mode  = str_pad( $realmode, 10, '-', STR_PAD_LEFT );
		$trans = array(
			'-' => '0',
			'r' => '4',
			'w' => '2',
			'x' => '1',
		);
		$mode  = strtr( $mode, $trans );

		$newmode  = $mode[0];
		$newmode .= $mode[1] + $mode[2] + $mode[3];
		$newmode .= $mode[4] + $mode[5] + $mode[6];
		$newmode .= $mode[7] + $mode[8] + $mode[9];

		return $newmode;
	}

	/**
	 * Determines if the string provided contains binary characters.
	 *
	 * @since 2.7.0
	 *
	 * @param string $text String to test against.
	 * @return bool True if string is binary, false otherwise.
	 */
	public function is_binary( $text ) {
		return (bool) preg_match( '|[^\x20-\x7E]|', $text ); // chr(32)..chr(127)
	}

	/**
	 * Changes the owner of a file or directory.
	 *
	 * Default behavior is to do nothing, override this in your subclass, if desired.
	 *
	 * @since 2.5.0
	 *
	 * @param string     $file      Path to the file or directory.
	 * @param string|int $owner     A user name or number.
	 * @param bool       $recursive Optional. If set to true, changes file owner recursively.
	 *                              Default false.
	 * @return bool True on success, false on failure.
	 */
	public function chown( $file, $owner, $recursive = false ) {
		return false;
	}

	/**
	 * Connects filesystem.
	 *
	 * @since 2.5.0
	 * @abstract
	 *
	 * @return bool True on success, false on failure (always true for WP_Filesystem_Direct).
	 */
	public function connect() {
		return true;
	}

	/**
	 * Reads entire file into a string.
	 *
	 * @since 2.5.0
	 * @abstract
	 *
	 * @param string $file Name of the file to read.
	 * @return string|false Read data on success, false on failure.
	 */
	public function get_contents( $file ) {
		return false;
	}

	/**
	 * Reads entire file into an array.
	 *
	 * @since 2.5.0
	 * @abstract
	 *
	 * @param string $file Path to the file.
	 * @return array|false File contents in an array on success, false on failure.
	 */
	public function get_contents_array( $file ) {
		return false;
	}

	/**
	 * Writes a string to a file.
	 *
	 * @since 2.5.0
	 * @abstract
	 *
	 * @param string    $file     Remote path to the file where to write the data.
	 * @param string    $contents The data to write.
	 * @param int|false $mode     Optional. The file permissions as octal number, usually 0644.
	 *                            Default false.
	 * @return bool True on success, false on failure.
	 */
	public function put_contents( $file, $contents, $mode = false ) {
		return false;
	}

	/**
	 * Gets the current working directory.
	 *
	 * @since 2.5.0
	 * @abstract
	 *
	 * @return string|false The current working directory on success, false on failure.
	 */
	public function cwd() {
		return false;
	}

	/**
	 * Changes current directory.
	 *
	 * @since 2.5.0
	 * @abstract
	 *
	 * @param string $dir The new current directory.
	 * @return bool True on success, false on failure.
	 */
	public function chdir( $dir ) {
		return false;
	}

	/**
	 * Changes the file group.
	 *
	 * @since 2.5.0
	 * @abstract
	 *
	 * @param string     $file      Path to the file.
	 * @param string|int $group     A group name or number.
	 * @param bool       $recursive Optional. If set to true, changes file group recursively.
	 *                              Default false.
	 * @return bool True on success, false on failure.
	 */
	public function chgrp( $file, $group, $recursive = false ) {
		return false;
	}

	/**
	 * Changes filesystem permissions.
	 *
	 * @since 2.5.0
	 * @abstract
	 *
	 * @param string    $file      Path to the file.
	 * @param int|false $mode      Optional. The permissions as octal number, usually 0644 for files,
	 *                             0755 for directories. Default false.
	 * @param bool      $recursive Optional. If set to true, changes file permissions recursively.
	 *                             Default false.
	 * @return bool True on success, false on failure.
	 */
	public function chmod( $file, $mode = false, $recursive = false ) {
		return false;
	}

	/**
	 * Gets the file owner.
	 *
	 * @since 2.5.0
	 * @abstract
	 *
	 * @param string $file Path to the file.
	 * @return string|false Username of the owner on success, false on failure.
	 */
	public function owner( $file ) {
		return false;
	}

	/**
	 * Gets the file's group.
	 *
	 * @since 2.5.0
	 * @abstract
	 *
	 * @param string $file Path to the file.
	 * @return string|false The group on success, false on failure.
	 */
	public function group( $file ) {
		return false;
	}

	/**
	 * Copies a file.
	 *
	 * @since 2.5.0
	 * @abstract
	 *
	 * @param string    $source      Path to the source file.
	 * @param string    $destination Path to the destination file.
	 * @param bool      $overwrite   Optional. Whether to overwrite the destination file if it exists.
	 *                               Default false.
	 * @param int|false $mode        Optional. The permissions as octal number, usually 0644 for files,
	 *                               0755 for dirs. Default false.
	 * @return bool True on success, false on failure.
	 */
	public function copy( $source, $destination, $overwrite = false, $mode = false ) {
		return false;
	}

	/**
	 * Moves a file.
	 *
	 * @since 2.5.0
	 * @abstract
	 *
	 * @param string $source      Path to the source file.
	 * @param string $destination Path to the destination file.
	 * @param bool   $overwrite   Optional. Whether to overwrite the destination file if it exists.
	 *                            Default false.
	 * @return bool True on success, false on failure.
	 */
	public function move( $source, $destination, $overwrite = false ) {
		return false;
	}

	/**
	 * Deletes a file or directory.
	 *
	 * @since 2.5.0
	 * @abstract
	 *
	 * @param string       $file      Path to the file or directory.
	 * @param bool         $recursive Optional. If set to true, deletes files and folders recursively.
	 *                                Default false.
	 * @param string|false $type      Type of resource. 'f' for file, 'd' for directory.
	 *                                Default false.
	 * @return bool True on success, false on failure.
	 */
	public function delete( $file, $recursive = false, $type = false ) {
		return false;
	}

	/**
	 * Checks if a file or directory exists.
	 *
	 * @since 2.5.0
	 * @abstract
	 *
	 * @param string $file Path to file or directory.
	 * @return bool Whether $file exists or not.
	 */
	public function exists( $file ) {
		return false;
	}

	/**
	 * Checks if resource is a file.
	 *
	 * @since 2.5.0
	 * @abstract
	 *
	 * @param string $file File path.
	 * @return bool Whether $file is a file.
	 */
	public function is_file( $file ) {
		return false;
	}

	/**
	 * Checks if resource is a directory.
	 *
	 * @since 2.5.0
	 * @abstract
	 *
	 * @param string $path Directory path.
	 * @return bool Whether $path is a directory.
	 */
	public function is_dir( $path ) {
		return false;
	}

	/**
	 * Checks if a file is readable.
	 *
	 * @since 2.5.0
	 * @abstract
	 *
	 * @param string $file Path to file.
	 * @return bool Whether $file is readable.
	 */
	public function is_readable( $file ) {
		return false;
	}

	/**
	 * Checks if a file or directory is writable.
	 *
	 * @since 2.5.0
	 * @abstract
	 *
	 * @param string $file Path to file or directory.
	 * @return bool Whether $file is writable.
	 */
	public function is_writable( $file ) {
		return false;
	}

	/**
	 * Gets the file's last access time.
	 *
	 * @since 2.5.0
	 * @abstract
	 *
	 * @param string $file Path to file.
	 * @return int|false Unix timestamp representing last access time, false on failure.
	 */
	public function atime( $file ) {
		return false;
	}

	/**
	 * Gets the file modification time.
	 *
	 * @since 2.5.0
	 * @abstract
	 *
	 * @param string $file Path to file.
	 * @return int|false Unix timestamp representing modification time, false on failure.
	 */
	public function mtime( $file ) {
		return false;
	}

	/**
	 * Gets the file size (in bytes).
	 *
	 * @since 2.5.0
	 * @abstract
	 *
	 * @param string $file Path to file.
	 * @return int|false Size of the file in bytes on success, false on failure.
	 */
	public function size( $file ) {
		return false;
	}

	/**
	 * Sets the access and modification times of a file.
	 *
	 * Note: If $file doesn't exist, it will be created.
	 *
	 * @since 2.5.0
	 * @abstract
	 *
	 * @param string $file  Path to file.
	 * @param int    $time  Optional. Modified time to set for file.
	 *                      Default 0.
	 * @param int    $atime Optional. Access time to set for file.
	 *                      Default 0.
	 * @return bool True on success, false on failure.
	 */
	public function touch( $file, $time = 0, $atime = 0 ) {
		return false;
	}

	/**
	 * Creates a directory.
	 *
	 * @since 2.5.0
	 * @abstract
	 *
	 * @param string           $path  Path for new directory.
	 * @param int|false        $chmod Optional. The permissions as octal number (or false to skip chmod).
	 *                                Default false.
	 * @param string|int|false $chown Optional. A user name or number (or false to skip chown).
	 *                                Default false.
	 * @param string|int|false $chgrp Optional. A group name or number (or false to skip chgrp).
	 *                                Default false.
	 * @return bool True on success, false on failure.
	 */
	public function mkdir( $path, $chmod = false, $chown = false, $chgrp = false ) {
		return false;
	}

	/**
	 * Deletes a directory.
	 *
	 * @since 2.5.0
	 * @abstract
	 *
	 * @param string $path      Path to directory.
	 * @param bool   $recursive Optional. Whether to recursively remove files/directories.
	 *                          Default false.
	 * @return bool True on success, false on failure.
	 */
	public function rmdir( $path, $recursive = false ) {
		return false;
	}

	/**
	 * Gets details for files in a directory or a specific file.
	 *
	 * @since 2.5.0
	 * @abstract
	 *
	 * @param string $path           Path to directory or file.
	 * @param bool   $include_hidden Optional. Whether to include details of hidden ("." prefixed) files.
	 *                               Default true.
	 * @param bool   $recursive      Optional. Whether to recursively include file details in nested directories.
	 *                               Default false.
	 * @return array|false {
	 *     Array of files. False if unable to list directory contents.
	 *
	 *     @type string $name        Name of the file or directory.
	 *     @type string $perms       *nix representation of permissions.
	 *     @type string $permsn      Octal representation of permissions.
	 *     @type string $owner       Owner name or ID.
	 *     @type int    $size        Size of file in bytes.
	 *     @type int    $lastmodunix Last modified unix timestamp.
	 *     @type mixed  $lastmod     Last modified month (3 letter) and day (without leading 0).
	 *     @type int    $time        Last modified time.
	 *     @type string $type        Type of resource. 'f' for file, 'd' for directory.
	 *     @type mixed  $files       If a directory and `$recursive` is true, contains another array of files.
	 * }
	 */
	public function dirlist( $path, $include_hidden = true, $recursive = false ) {
		return false;
	}

}