michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
michael@0:  * You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: /**
michael@0:  * Synchronous front-end for the JavaScript OS.File library.
michael@0:  * Unix implementation.
michael@0:  *
michael@0:  * This front-end is meant to be imported by a worker thread.
michael@0:  */
michael@0: 
michael@0: {
michael@0:   if (typeof Components != "undefined") {
michael@0:     // We do not wish osfile_unix_front.jsm to be used directly as a main thread
michael@0:     // module yet.
michael@0: 
michael@0:     throw new Error("osfile_unix_front.jsm cannot be used from the main thread yet");
michael@0:   }
michael@0:   (function(exports) {
michael@0:      "use strict";
michael@0: 
michael@0:      // exports.OS.Unix is created by osfile_unix_back.jsm
michael@0:      if (exports.OS && exports.OS.File) {
michael@0:        return; // Avoid double-initialization
michael@0:      }
michael@0: 
michael@0:      let SharedAll = require("resource://gre/modules/osfile/osfile_shared_allthreads.jsm");
michael@0:      let Path = require("resource://gre/modules/osfile/ospath.jsm");
michael@0:      let SysAll = require("resource://gre/modules/osfile/osfile_unix_allthreads.jsm");
michael@0:      exports.OS.Unix.File._init();
michael@0:      let LOG = SharedAll.LOG.bind(SharedAll, "Unix front-end");
michael@0:      let Const = SharedAll.Constants.libc;
michael@0:      let UnixFile = exports.OS.Unix.File;
michael@0:      let Type = UnixFile.Type;
michael@0: 
michael@0:      /**
michael@0:       * Representation of a file.
michael@0:       *
michael@0:       * You generally do not need to call this constructor yourself. Rather,
michael@0:       * to open a file, use function |OS.File.open|.
michael@0:       *
michael@0:       * @param fd A OS-specific file descriptor.
michael@0:       * @param {string} path File path of the file handle, used for error-reporting.
michael@0:       * @constructor
michael@0:       */
michael@0:      let File = function File(fd, path) {
michael@0:        exports.OS.Shared.AbstractFile.call(this, fd, path);
michael@0:        this._closeResult = null;
michael@0:      };
michael@0:      File.prototype = Object.create(exports.OS.Shared.AbstractFile.prototype);
michael@0: 
michael@0:      /**
michael@0:       * Close the file.
michael@0:       *
michael@0:       * This method has no effect if the file is already closed. However,
michael@0:       * if the first call to |close| has thrown an error, further calls
michael@0:       * will throw the same error.
michael@0:       *
michael@0:       * @throws File.Error If closing the file revealed an error that could
michael@0:       * not be reported earlier.
michael@0:       */
michael@0:      File.prototype.close = function close() {
michael@0:        if (this._fd) {
michael@0:          let fd = this._fd;
michael@0:          this._fd = null;
michael@0:         // Call |close(fd)|, detach finalizer if any
michael@0:          // (|fd| may not be a CDataFinalizer if it has been
michael@0:          // instantiated from a controller thread).
michael@0:          let result = UnixFile._close(fd);
michael@0:          if (typeof fd == "object" && "forget" in fd) {
michael@0:            fd.forget();
michael@0:          }
michael@0:          if (result == -1) {
michael@0:            this._closeResult = new File.Error("close", ctypes.errno, this._path);
michael@0:          }
michael@0:        }
michael@0:        if (this._closeResult) {
michael@0:          throw this._closeResult;
michael@0:        }
michael@0:        return;
michael@0:      };
michael@0: 
michael@0:      /**
michael@0:       * Read some bytes from a file.
michael@0:       *
michael@0:       * @param {C pointer} buffer A buffer for holding the data
michael@0:       * once it is read.
michael@0:       * @param {number} nbytes The number of bytes to read. It must not
michael@0:       * exceed the size of |buffer| in bytes but it may exceed the number
michael@0:       * of bytes unread in the file.
michael@0:       * @param {*=} options Additional options for reading. Ignored in
michael@0:       * this implementation.
michael@0:       *
michael@0:       * @return {number} The number of bytes effectively read. If zero,
michael@0:       * the end of the file has been reached.
michael@0:       * @throws {OS.File.Error} In case of I/O error.
michael@0:       */
michael@0:      File.prototype._read = function _read(buffer, nbytes, options = {}) {
michael@0:       // Populate the page cache with data from a file so the subsequent reads
michael@0:       // from that file will not block on disk I/O.
michael@0:        if (typeof(UnixFile.posix_fadvise) === 'function' &&
michael@0:            (options.sequential || !("sequential" in options))) {
michael@0:          UnixFile.posix_fadvise(this.fd, 0, nbytes,
michael@0:           OS.Constants.libc.POSIX_FADV_SEQUENTIAL);
michael@0:        }
michael@0:        return throw_on_negative("read",
michael@0:          UnixFile.read(this.fd, buffer, nbytes),
michael@0:          this._path
michael@0:        );
michael@0:      };
michael@0: 
michael@0:      /**
michael@0:       * Write some bytes to a file.
michael@0:       *
michael@0:       * @param {C pointer} buffer A buffer holding the data that must be
michael@0:       * written.
michael@0:       * @param {number} nbytes The number of bytes to write. It must not
michael@0:       * exceed the size of |buffer| in bytes.
michael@0:       * @param {*=} options Additional options for writing. Ignored in
michael@0:       * this implementation.
michael@0:       *
michael@0:       * @return {number} The number of bytes effectively written.
michael@0:       * @throws {OS.File.Error} In case of I/O error.
michael@0:       */
michael@0:      File.prototype._write = function _write(buffer, nbytes, options = {}) {
michael@0:        return throw_on_negative("write",
michael@0:          UnixFile.write(this.fd, buffer, nbytes),
michael@0:          this._path
michael@0:        );
michael@0:      };
michael@0: 
michael@0:      /**
michael@0:       * Return the current position in the file.
michael@0:       */
michael@0:      File.prototype.getPosition = function getPosition(pos) {
michael@0:          return this.setPosition(0, File.POS_CURRENT);
michael@0:      };
michael@0: 
michael@0:      /**
michael@0:       * Change the current position in the file.
michael@0:       *
michael@0:       * @param {number} pos The new position. Whether this position
michael@0:       * is considered from the current position, from the start of
michael@0:       * the file or from the end of the file is determined by
michael@0:       * argument |whence|.  Note that |pos| may exceed the length of
michael@0:       * the file.
michael@0:       * @param {number=} whence The reference position. If omitted
michael@0:       * or |OS.File.POS_START|, |pos| is relative to the start of the
michael@0:       * file.  If |OS.File.POS_CURRENT|, |pos| is relative to the
michael@0:       * current position in the file. If |OS.File.POS_END|, |pos| is
michael@0:       * relative to the end of the file.
michael@0:       *
michael@0:       * @return The new position in the file.
michael@0:       */
michael@0:      File.prototype.setPosition = function setPosition(pos, whence) {
michael@0:        if (whence === undefined) {
michael@0:          whence = Const.SEEK_SET;
michael@0:        }
michael@0:        return throw_on_negative("setPosition",
michael@0:          UnixFile.lseek(this.fd, pos, whence),
michael@0:          this._path
michael@0:        );
michael@0:      };
michael@0: 
michael@0:      /**
michael@0:       * Fetch the information on the file.
michael@0:       *
michael@0:       * @return File.Info The information on |this| file.
michael@0:       */
michael@0:      File.prototype.stat = function stat() {
michael@0:        throw_on_negative("stat", UnixFile.fstat(this.fd, gStatDataPtr),
michael@0:                          this._path);
michael@0:        return new File.Info(gStatData, this._path);
michael@0:      };
michael@0: 
michael@0:      /**
michael@0:       * Set the file's access permissions.  Without any options, the
michael@0:       * permissions are set to an approximation of what they would
michael@0:       * have been if the file had been created in its current
michael@0:       * directory in the "most typical" fashion for the operating
michael@0:       * system.  In the current implementation, this means we set
michael@0:       * the POSIX file mode to (0666 & ~umask).
michael@0:       *
michael@0:       * This operation is likely to fail if applied to a file that was
michael@0:       * not created by the currently running program (more precisely,
michael@0:       * if it was created by a program running under a different OS-level
michael@0:       * user account).  It may also fail, or silently do nothing, if the
michael@0:       * filesystem containing the file does not support access permissions.
michael@0:       *
michael@0:       * @param {*=} options
michael@0:       * - {number} unixMode     If present, the POSIX file mode is set to
michael@0:       *                         exactly this value, unless |unixHonorUmask| is
michael@0:       *                         also present.
michael@0:       * - {bool} unixHonorUmask If true, any |unixMode| value is modified by
michael@0:       *                         the process umask, as open() would have done.
michael@0:       */
michael@0:      File.prototype.setPermissions = function setPermissions(options = {}) {
michael@0:        throw_on_negative("setPermissions",
michael@0:                          UnixFile.fchmod(this.fd, unixMode(options)),
michael@0:                          this._path);
michael@0:      };
michael@0: 
michael@0:      /**
michael@0:       * Set the last access and modification date of the file.
michael@0:       * The time stamp resolution is 1 second at best, but might be worse
michael@0:       * depending on the platform.
michael@0:       *
michael@0:       * @param {Date,number=} accessDate The last access date. If numeric,
michael@0:       * milliseconds since epoch. If omitted or null, then the current date
michael@0:       * will be used.
michael@0:       * @param {Date,number=} modificationDate The last modification date. If
michael@0:       * numeric, milliseconds since epoch. If omitted or null, then the current
michael@0:       * date will be used.
michael@0:       *
michael@0:       * @throws {TypeError} In case of invalid parameters.
michael@0:       * @throws {OS.File.Error} In case of I/O error.
michael@0:       */
michael@0:      File.prototype.setDates = function setDates(accessDate, modificationDate) {
michael@0:        accessDate = normalizeDate("File.prototype.setDates", accessDate);
michael@0:        modificationDate = normalizeDate("File.prototype.setDates",
michael@0:                                         modificationDate);
michael@0:        gTimevals[0].tv_sec = (accessDate / 1000) | 0;
michael@0:        gTimevals[0].tv_usec = 0;
michael@0:        gTimevals[1].tv_sec = (modificationDate / 1000) | 0;
michael@0:        gTimevals[1].tv_usec = 0;
michael@0:        throw_on_negative("setDates",
michael@0:                          UnixFile.futimes(this.fd, gTimevalsPtr),
michael@0:                          this._path);
michael@0:      };
michael@0: 
michael@0:      /**
michael@0:       * Flushes the file's buffers and causes all buffered data
michael@0:       * to be written.
michael@0:       * Disk flushes are very expensive and therefore should be used carefully,
michael@0:       * sparingly and only in scenarios where it is vital that data survives
michael@0:       * system crashes. Even though the function will be executed off the
michael@0:       * main-thread, it might still affect the overall performance of any
michael@0:       * running application.
michael@0:       *
michael@0:       * @throws {OS.File.Error} In case of I/O error.
michael@0:       */
michael@0:      File.prototype.flush = function flush() {
michael@0:        throw_on_negative("flush", UnixFile.fsync(this.fd), this._path);
michael@0:      };
michael@0: 
michael@0:      // The default unix mode for opening (0600)
michael@0:      const DEFAULT_UNIX_MODE = 384;
michael@0: 
michael@0:      /**
michael@0:       * Open a file
michael@0:       *
michael@0:       * @param {string} path The path to the file.
michael@0:       * @param {*=} mode The opening mode for the file, as
michael@0:       * an object that may contain the following fields:
michael@0:       *
michael@0:       * - {bool} truncate If |true|, the file will be opened
michael@0:       *  for writing. If the file does not exist, it will be
michael@0:       *  created. If the file exists, its contents will be
michael@0:       *  erased. Cannot be specified with |create|.
michael@0:       * - {bool} create If |true|, the file will be opened
michael@0:       *  for writing. If the file exists, this function fails.
michael@0:       *  If the file does not exist, it will be created. Cannot
michael@0:       *  be specified with |truncate| or |existing|.
michael@0:       * - {bool} existing. If the file does not exist, this function
michael@0:       *  fails. Cannot be specified with |create|.
michael@0:       * - {bool} read If |true|, the file will be opened for
michael@0:       *  reading. The file may also be opened for writing, depending
michael@0:       *  on the other fields of |mode|.
michael@0:       * - {bool} write If |true|, the file will be opened for
michael@0:       *  writing. The file may also be opened for reading, depending
michael@0:       *  on the other fields of |mode|.
michael@0:       * - {bool} append If |true|, the file will be opened for appending,
michael@0:       *  meaning the equivalent of |.setPosition(0, POS_END)| is executed
michael@0:       *  before each write. The default is |true|, i.e. opening a file for
michael@0:       *  appending. Specify |append: false| to open the file in regular mode.
michael@0:       *
michael@0:       * If neither |truncate|, |create| or |write| is specified, the file
michael@0:       * is opened for reading.
michael@0:       *
michael@0:       * Note that |false|, |null| or |undefined| flags are simply ignored.
michael@0:       *
michael@0:       * @param {*=} options Additional options for file opening. This
michael@0:       * implementation interprets the following fields:
michael@0:       *
michael@0:       * - {number} unixFlags If specified, file opening flags, as
michael@0:       *  per libc function |open|. Replaces |mode|.
michael@0:       * - {number} unixMode If specified, a file creation mode,
michael@0:       *  as per libc function |open|. If unspecified, files are
michael@0:       *  created with a default mode of 0600 (file is private to the
michael@0:       *  user, the user can read and write).
michael@0:       *
michael@0:       * @return {File} A file object.
michael@0:       * @throws {OS.File.Error} If the file could not be opened.
michael@0:       */
michael@0:      File.open = function Unix_open(path, mode, options = {}) {
michael@0:        let omode = options.unixMode !== undefined ?
michael@0:                      options.unixMode : DEFAULT_UNIX_MODE;
michael@0:        let flags;
michael@0:        if (options.unixFlags !== undefined) {
michael@0:          flags = options.unixFlags;
michael@0:        } else {
michael@0:          mode = OS.Shared.AbstractFile.normalizeOpenMode(mode);
michael@0:          // Handle read/write
michael@0:          if (!mode.write) {
michael@0:            flags = Const.O_RDONLY;
michael@0:          } else if (mode.read) {
michael@0:            flags = Const.O_RDWR;
michael@0:          } else {
michael@0:            flags = Const.O_WRONLY;
michael@0:          }
michael@0:          // Finally, handle create/existing/trunc
michael@0:          if (mode.trunc) {
michael@0:            if (mode.existing) {
michael@0:              flags |= Const.O_TRUNC;
michael@0:            } else {
michael@0:              flags |= Const.O_CREAT | Const.O_TRUNC;
michael@0:            }
michael@0:          } else if (mode.create) {
michael@0:            flags |= Const.O_CREAT | Const.O_EXCL;
michael@0:          } else if (mode.read && !mode.write) {
michael@0:            // flags are sufficient
michael@0:          } else if (!mode.existing) {
michael@0:            flags |= Const.O_CREAT;
michael@0:          }
michael@0:          if (mode.append) {
michael@0:            flags |= Const.O_APPEND;
michael@0:          }
michael@0:        }
michael@0:        return error_or_file(UnixFile.open(path, flags, omode), path);
michael@0:      };
michael@0: 
michael@0:      /**
michael@0:       * Checks if a file exists
michael@0:       *
michael@0:       * @param {string} path The path to the file.
michael@0:       *
michael@0:       * @return {bool} true if the file exists, false otherwise.
michael@0:       */
michael@0:      File.exists = function Unix_exists(path) {
michael@0:        if (UnixFile.access(path, Const.F_OK) == -1) {
michael@0:          return false;
michael@0:        } else {
michael@0:          return true;
michael@0:        }
michael@0:      };
michael@0: 
michael@0:      /**
michael@0:       * Remove an existing file.
michael@0:       *
michael@0:       * @param {string} path The name of the file.
michael@0:       * @param {*=} options Additional options.
michael@0:       *   - {bool} ignoreAbsent If |false|, throw an error if the file does
michael@0:       *     not exist. |true| by default.
michael@0:       *
michael@0:       * @throws {OS.File.Error} In case of I/O error.
michael@0:       */
michael@0:      File.remove = function remove(path, options = {}) {
michael@0:        let result = UnixFile.unlink(path);
michael@0:        if (result == -1) {
michael@0:          if ((!("ignoreAbsent" in options) || options.ignoreAbsent) &&
michael@0:              ctypes.errno == Const.ENOENT) {
michael@0:            return;
michael@0:          }
michael@0:          throw new File.Error("remove", ctypes.errno, path);
michael@0:        }
michael@0:      };
michael@0: 
michael@0:      /**
michael@0:       * Remove an empty directory.
michael@0:       *
michael@0:       * @param {string} path The name of the directory to remove.
michael@0:       * @param {*=} options Additional options.
michael@0:       *   - {bool} ignoreAbsent If |false|, throw an error if the directory
michael@0:       *     does not exist. |true| by default
michael@0:       */
michael@0:      File.removeEmptyDir = function removeEmptyDir(path, options = {}) {
michael@0:        let result = UnixFile.rmdir(path);
michael@0:        if (result == -1) {
michael@0:          if ((!("ignoreAbsent" in options) || options.ignoreAbsent) &&
michael@0:              ctypes.errno == Const.ENOENT) {
michael@0:            return;
michael@0:          }
michael@0:          throw new File.Error("removeEmptyDir", ctypes.errno, path);
michael@0:        }
michael@0:      };
michael@0: 
michael@0:      /**
michael@0:       * Gets the number of bytes available on disk to the current user.
michael@0:       *
michael@0:       * @param {string} sourcePath Platform-specific path to a directory on 
michael@0:       * the disk to query for free available bytes.
michael@0:       *
michael@0:       * @return {number} The number of bytes available for the current user.
michael@0:       * @throws {OS.File.Error} In case of any error.
michael@0:       */
michael@0:      File.getAvailableFreeSpace = function Unix_getAvailableFreeSpace(sourcePath) {
michael@0:        let fileSystemInfo = new Type.statvfs.implementation();
michael@0:        let fileSystemInfoPtr = fileSystemInfo.address();
michael@0: 
michael@0:        throw_on_negative("statvfs",  UnixFile.statvfs(sourcePath, fileSystemInfoPtr));
michael@0: 
michael@0:        let bytes = new Type.uint64_t.implementation(
michael@0:                         fileSystemInfo.f_bsize * fileSystemInfo.f_bavail);
michael@0: 
michael@0:        return bytes.value;
michael@0:      };
michael@0: 
michael@0:      /**
michael@0:       * Default mode for opening directories.
michael@0:       */
michael@0:      const DEFAULT_UNIX_MODE_DIR = Const.S_IRWXU;
michael@0: 
michael@0:      /**
michael@0:       * Create a directory.
michael@0:       *
michael@0:       * @param {string} path The name of the directory.
michael@0:       * @param {*=} options Additional options. This
michael@0:       * implementation interprets the following fields:
michael@0:       *
michael@0:       * - {number} unixMode If specified, a file creation mode,
michael@0:       * as per libc function |mkdir|. If unspecified, dirs are
michael@0:       * created with a default mode of 0700 (dir is private to
michael@0:       * the user, the user can read, write and execute).
michael@0:       * - {bool} ignoreExisting If |false|, throw error if the directory
michael@0:       * already exists. |true| by default
michael@0:       * - {string} from If specified, the call to |makeDir| creates all the
michael@0:       * ancestors of |path| that are descendants of |from|. Note that |from|
michael@0:       * and its existing descendants must be user-writeable and that |path|
michael@0:       * must be a descendant of |from|.
michael@0:       * Example:
michael@0:       *   makeDir(Path.join(profileDir, "foo", "bar"), { from: profileDir });
michael@0:       *  creates directories profileDir/foo, profileDir/foo/bar
michael@0:        */
michael@0:      File._makeDir = function makeDir(path, options = {}) {
michael@0:        let omode = options.unixMode !== undefined ? options.unixMode : DEFAULT_UNIX_MODE_DIR;
michael@0:        let result = UnixFile.mkdir(path, omode);
michael@0:        if (result == -1) {
michael@0:          if ((!("ignoreExisting" in options) || options.ignoreExisting) &&
michael@0:              (ctypes.errno == Const.EEXIST || ctypes.errno == Const.EISDIR)) {
michael@0:            return;
michael@0:          }
michael@0:          throw new File.Error("makeDir", ctypes.errno, path);
michael@0:        }
michael@0:      };
michael@0: 
michael@0:      /**
michael@0:       * Copy a file to a destination.
michael@0:       *
michael@0:       * @param {string} sourcePath The platform-specific path at which
michael@0:       * the file may currently be found.
michael@0:       * @param {string} destPath The platform-specific path at which the
michael@0:       * file should be copied.
michael@0:       * @param {*=} options An object which may contain the following fields:
michael@0:       *
michael@0:       * @option {bool} noOverwrite - If set, this function will fail if
michael@0:       * a file already exists at |destPath|. Otherwise, if this file exists,
michael@0:       * it will be erased silently.
michael@0:       *
michael@0:       * @throws {OS.File.Error} In case of any error.
michael@0:       *
michael@0:       * General note: The behavior of this function is defined only when
michael@0:       * it is called on a single file. If it is called on a directory, the
michael@0:       * behavior is undefined and may not be the same across all platforms.
michael@0:       *
michael@0:       * General note: The behavior of this function with respect to metadata
michael@0:       * is unspecified. Metadata may or may not be copied with the file. The
michael@0:       * behavior may not be the same across all platforms.
michael@0:       */
michael@0:      File.copy = null;
michael@0: 
michael@0:      /**
michael@0:       * Move a file to a destination.
michael@0:       *
michael@0:       * @param {string} sourcePath The platform-specific path at which
michael@0:       * the file may currently be found.
michael@0:       * @param {string} destPath The platform-specific path at which the
michael@0:       * file should be moved.
michael@0:       * @param {*=} options An object which may contain the following fields:
michael@0:       *
michael@0:       * @option {bool} noOverwrite - If set, this function will fail if
michael@0:       * a file already exists at |destPath|. Otherwise, if this file exists,
michael@0:       * it will be erased silently.
michael@0:       * @option {bool} noCopy - If set, this function will fail if the
michael@0:       * operation is more sophisticated than a simple renaming, i.e. if
michael@0:       * |sourcePath| and |destPath| are not situated on the same device.
michael@0:       *
michael@0:       * @throws {OS.File.Error} In case of any error.
michael@0:       *
michael@0:       * General note: The behavior of this function is defined only when
michael@0:       * it is called on a single file. If it is called on a directory, the
michael@0:       * behavior is undefined and may not be the same across all platforms.
michael@0:       *
michael@0:       * General note: The behavior of this function with respect to metadata
michael@0:       * is unspecified. Metadata may or may not be moved with the file. The
michael@0:       * behavior may not be the same across all platforms.
michael@0:       */
michael@0:      File.move = null;
michael@0: 
michael@0:      if (UnixFile.copyfile) {
michael@0:        // This implementation uses |copyfile(3)|, from the BSD library.
michael@0:        // Adding copying of hierarchies and/or attributes is just a flag
michael@0:        // away.
michael@0:        File.copy = function copyfile(sourcePath, destPath, options = {}) {
michael@0:          let flags = Const.COPYFILE_DATA;
michael@0:          if (options.noOverwrite) {
michael@0:            flags |= Const.COPYFILE_EXCL;
michael@0:          }
michael@0:          throw_on_negative("copy",
michael@0:            UnixFile.copyfile(sourcePath, destPath, null, flags),
michael@0:            sourcePath
michael@0:          );
michael@0:        };
michael@0:      } else {
michael@0:        // If the OS does not implement file copying for us, we need to
michael@0:        // implement it ourselves. For this purpose, we need to define
michael@0:        // a pumping function.
michael@0: 
michael@0:        /**
michael@0:         * Copy bytes from one file to another one.
michael@0:         *
michael@0:         * @param {File} source The file containing the data to be copied. It
michael@0:         * should be opened for reading.
michael@0:         * @param {File} dest The file to which the data should be written. It
michael@0:         * should be opened for writing.
michael@0:         * @param {*=} options An object which may contain the following fields:
michael@0:         *
michael@0:         * @option {number} nbytes The maximal number of bytes to
michael@0:         * copy. If unspecified, copy everything from the current
michael@0:         * position.
michael@0:         * @option {number} bufSize A hint regarding the size of the
michael@0:         * buffer to use for copying. The implementation may decide to
michael@0:         * ignore this hint.
michael@0:         * @option {bool} unixUserland Will force the copy operation to be
michael@0:         * caried out in user land, instead of using optimized syscalls such
michael@0:         * as splice(2).
michael@0:         *
michael@0:         * @throws {OS.File.Error} In case of error.
michael@0:         */
michael@0:        let pump;
michael@0: 
michael@0:        // A buffer used by |pump_userland|
michael@0:        let pump_buffer = null;
michael@0: 
michael@0:        // An implementation of |pump| using |read|/|write|
michael@0:        let pump_userland = function pump_userland(source, dest, options = {}) {
michael@0:          let bufSize = options.bufSize > 0 ? options.bufSize : 4096;
michael@0:          let nbytes = options.nbytes > 0 ? options.nbytes : Infinity;
michael@0:          if (!pump_buffer || pump_buffer.length < bufSize) {
michael@0:            pump_buffer = new (ctypes.ArrayType(ctypes.char))(bufSize);
michael@0:          }
michael@0:          let read = source._read.bind(source);
michael@0:          let write = dest._write.bind(dest);
michael@0:          // Perform actual copy
michael@0:          let total_read = 0;
michael@0:          while (true) {
michael@0:            let chunk_size = Math.min(nbytes, bufSize);
michael@0:            let bytes_just_read = read(pump_buffer, bufSize);
michael@0:            if (bytes_just_read == 0) {
michael@0:              return total_read;
michael@0:            }
michael@0:            total_read += bytes_just_read;
michael@0:            let bytes_written = 0;
michael@0:            do {
michael@0:              bytes_written += write(
michael@0:                pump_buffer.addressOfElement(bytes_written),
michael@0:                bytes_just_read - bytes_written
michael@0:              );
michael@0:            } while (bytes_written < bytes_just_read);
michael@0:            nbytes -= bytes_written;
michael@0:            if (nbytes <= 0) {
michael@0:              return total_read;
michael@0:            }
michael@0:          }
michael@0:        };
michael@0: 
michael@0:        // Fortunately, under Linux, that pumping function can be optimized.
michael@0:        if (UnixFile.splice) {
michael@0:          const BUFSIZE = 1 << 17;
michael@0: 
michael@0:          // An implementation of |pump| using |splice| (for Linux/Android)
michael@0:          pump = function pump_splice(source, dest, options = {}) {
michael@0:            let nbytes = options.nbytes > 0 ? options.nbytes : Infinity;
michael@0:            let pipe = [];
michael@0:            throw_on_negative("pump", UnixFile.pipe(pipe));
michael@0:            let pipe_read = pipe[0];
michael@0:            let pipe_write = pipe[1];
michael@0:            let source_fd = source.fd;
michael@0:            let dest_fd = dest.fd;
michael@0:            let total_read = 0;
michael@0:            let total_written = 0;
michael@0:            try {
michael@0:              while (true) {
michael@0:                let chunk_size = Math.min(nbytes, BUFSIZE);
michael@0:                let bytes_read = throw_on_negative("pump",
michael@0:                  UnixFile.splice(source_fd, null,
michael@0:                  pipe_write, null, chunk_size, 0)
michael@0:                );
michael@0:                if (!bytes_read) {
michael@0:                  break;
michael@0:                }
michael@0:                total_read += bytes_read;
michael@0:                let bytes_written = throw_on_negative(
michael@0:                  "pump",
michael@0:                  UnixFile.splice(pipe_read, null,
michael@0:                    dest_fd, null, bytes_read,
michael@0:                      (bytes_read == chunk_size)?Const.SPLICE_F_MORE:0
michael@0:                ));
michael@0:                if (!bytes_written) {
michael@0:                  // This should never happen
michael@0:                  throw new Error("Internal error: pipe disconnected");
michael@0:                }
michael@0:                total_written += bytes_written;
michael@0:                nbytes -= bytes_read;
michael@0:                if (!nbytes) {
michael@0:                  break;
michael@0:                }
michael@0:              }
michael@0:              return total_written;
michael@0:            } catch (x) {
michael@0:              if (x.unixErrno == Const.EINVAL) {
michael@0:                // We *might* be on a file system that does not support splice.
michael@0:                // Try again with a fallback pump.
michael@0:                if (total_read) {
michael@0:                  source.setPosition(-total_read, File.POS_CURRENT);
michael@0:                }
michael@0:                if (total_written) {
michael@0:                  dest.setPosition(-total_written, File.POS_CURRENT);
michael@0:                }
michael@0:                return pump_userland(source, dest, options);
michael@0:              }
michael@0:              throw x;
michael@0:            } finally {
michael@0:              pipe_read.dispose();
michael@0:              pipe_write.dispose();
michael@0:            }
michael@0:          };
michael@0:        } else {
michael@0:          // Fallback implementation of pump for other Unix platforms.
michael@0:          pump = pump_userland;
michael@0:        }
michael@0: 
michael@0:        // Implement |copy| using |pump|.
michael@0:        // This implementation would require some work before being able to
michael@0:        // copy directories
michael@0:        File.copy = function copy(sourcePath, destPath, options = {}) {
michael@0:          let source, dest;
michael@0:          let result;
michael@0:          try {
michael@0:            source = File.open(sourcePath);
michael@0:            // Need to open the output file with |append:false|, or else |splice|
michael@0:            // won't work.
michael@0:            if (options.noOverwrite) {
michael@0:              dest = File.open(destPath, {create:true, append:false});
michael@0:            } else {
michael@0:              dest = File.open(destPath, {trunc:true, append:false});
michael@0:            }
michael@0:            if (options.unixUserland) {
michael@0:              result = pump_userland(source, dest, options);
michael@0:            } else {
michael@0:              result = pump(source, dest, options);
michael@0:            }
michael@0:          } catch (x) {
michael@0:            if (dest) {
michael@0:              dest.close();
michael@0:            }
michael@0:            if (source) {
michael@0:              source.close();
michael@0:            }
michael@0:            throw x;
michael@0:          }
michael@0:        };
michael@0:      } // End of definition of copy
michael@0: 
michael@0:      // Implement |move| using |rename| (wherever possible) or |copy|
michael@0:      // (if files are on distinct devices).
michael@0:      File.move = function move(sourcePath, destPath, options = {}) {
michael@0:        // An implementation using |rename| whenever possible or
michael@0:        // |File.pump| when required, for other Unices.
michael@0:        // It can move directories on one file system, not
michael@0:        // across file systems
michael@0: 
michael@0:        // If necessary, fail if the destination file exists
michael@0:        if (options.noOverwrite) {
michael@0:          let fd = UnixFile.open(destPath, Const.O_RDONLY, 0);
michael@0:          if (fd != -1) {
michael@0:            fd.dispose();
michael@0:            // The file exists and we have access
michael@0:            throw new File.Error("move", Const.EEXIST, sourcePath);
michael@0:          } else if (ctypes.errno == Const.EACCESS) {
michael@0:            // The file exists and we don't have access
michael@0:            throw new File.Error("move", Const.EEXIST, sourcePath);
michael@0:          }
michael@0:        }
michael@0: 
michael@0:        // If we can, rename the file
michael@0:        let result = UnixFile.rename(sourcePath, destPath);
michael@0:        if (result != -1)
michael@0:          return;
michael@0: 
michael@0:        // If the error is not EXDEV ("not on the same device"),
michael@0:        // or if the error is EXDEV and we have passed an option
michael@0:        // that prevents us from crossing devices, throw the
michael@0:        // error.
michael@0:        if (ctypes.errno != Const.EXDEV || options.noCopy) {
michael@0:          throw new File.Error("move", ctypes.errno, sourcePath);
michael@0:        }
michael@0: 
michael@0:        // Otherwise, copy and remove.
michael@0:        File.copy(sourcePath, destPath, options);
michael@0:        // FIXME: Clean-up in case of copy error?
michael@0:        File.remove(sourcePath);
michael@0:      };
michael@0: 
michael@0:      File.unixSymLink = function unixSymLink(sourcePath, destPath) {
michael@0:        throw_on_negative("symlink", UnixFile.symlink(sourcePath, destPath),
michael@0:            sourcePath);
michael@0:      };
michael@0: 
michael@0:      /**
michael@0:       * Iterate on one directory.
michael@0:       *
michael@0:       * This iterator will not enter subdirectories.
michael@0:       *
michael@0:       * @param {string} path The directory upon which to iterate.
michael@0:       * @param {*=} options Ignored in this implementation.
michael@0:       *
michael@0:       * @throws {File.Error} If |path| does not represent a directory or
michael@0:       * if the directory cannot be iterated.
michael@0:       * @constructor
michael@0:       */
michael@0:      File.DirectoryIterator = function DirectoryIterator(path, options) {
michael@0:        exports.OS.Shared.AbstractFile.AbstractIterator.call(this);
michael@0:        this._path = path;
michael@0:        this._dir = UnixFile.opendir(this._path);
michael@0:        if (this._dir == null) {
michael@0:          let error = ctypes.errno;
michael@0:          if (error != Const.ENOENT) {
michael@0:            throw new File.Error("DirectoryIterator", error, path);
michael@0:          }
michael@0:          this._exists = false;
michael@0:          this._closed = true;
michael@0:        } else {
michael@0:          this._exists = true;
michael@0:          this._closed = false;
michael@0:        }
michael@0:      };
michael@0:      File.DirectoryIterator.prototype = Object.create(exports.OS.Shared.AbstractFile.AbstractIterator.prototype);
michael@0: 
michael@0:      /**
michael@0:       * Return the next entry in the directory, if any such entry is
michael@0:       * available.
michael@0:       *
michael@0:       * Skip special directories "." and "..".
michael@0:       *
michael@0:       * @return {File.Entry} The next entry in the directory.
michael@0:       * @throws {StopIteration} Once all files in the directory have been
michael@0:       * encountered.
michael@0:       */
michael@0:      File.DirectoryIterator.prototype.next = function next() {
michael@0:        if (!this._exists) {
michael@0:          throw File.Error.noSuchFile("DirectoryIterator.prototype.next", this._path);
michael@0:        }
michael@0:        if (this._closed) {
michael@0:          throw StopIteration;
michael@0:        }
michael@0:        for (let entry = UnixFile.readdir(this._dir);
michael@0:             entry != null && !entry.isNull();
michael@0:             entry = UnixFile.readdir(this._dir)) {
michael@0:          let contents = entry.contents;
michael@0:          let name = contents.d_name.readString();
michael@0:          if (name == "." || name == "..") {
michael@0:            continue;
michael@0:          }
michael@0: 
michael@0:          let isDir, isSymLink;
michael@0:          if (!("d_type" in contents)) {
michael@0:            // |dirent| doesn't have d_type on some platforms (e.g. Solaris).
michael@0:            let path = Path.join(this._path, name);
michael@0:            throw_on_negative("lstat", UnixFile.lstat(path, gStatDataPtr), this._path);
michael@0:            isDir = (gStatData.st_mode & Const.S_IFMT) == Const.S_IFDIR;
michael@0:            isSymLink = (gStatData.st_mode & Const.S_IFMT) == Const.S_IFLNK;
michael@0:          } else {
michael@0:            isDir = contents.d_type == Const.DT_DIR;
michael@0:            isSymLink = contents.d_type == Const.DT_LNK;
michael@0:          }
michael@0: 
michael@0:          return new File.DirectoryIterator.Entry(isDir, isSymLink, name, this._path);
michael@0:        }
michael@0:        this.close();
michael@0:        throw StopIteration;
michael@0:      };
michael@0: 
michael@0:      /**
michael@0:       * Close the iterator and recover all resources.
michael@0:       * You should call this once you have finished iterating on a directory.
michael@0:       */
michael@0:      File.DirectoryIterator.prototype.close = function close() {
michael@0:        if (this._closed) return;
michael@0:        this._closed = true;
michael@0:        UnixFile.closedir(this._dir);
michael@0:        this._dir = null;
michael@0:      };
michael@0: 
michael@0:     /**
michael@0:      * Determine whether the directory exists.
michael@0:      *
michael@0:      * @return {boolean}
michael@0:      */
michael@0:      File.DirectoryIterator.prototype.exists = function exists() {
michael@0:        return this._exists;
michael@0:      };
michael@0: 
michael@0:      /**
michael@0:       * Return directory as |File|
michael@0:       */
michael@0:      File.DirectoryIterator.prototype.unixAsFile = function unixAsFile() {
michael@0:        if (!this._dir) throw File.Error.closed("unixAsFile", this._path);
michael@0:        return error_or_file(UnixFile.dirfd(this._dir), this._path);
michael@0:      };
michael@0: 
michael@0:      /**
michael@0:       * An entry in a directory.
michael@0:       */
michael@0:      File.DirectoryIterator.Entry = function Entry(isDir, isSymLink, name, parent) {
michael@0:        // Copy the relevant part of |unix_entry| to ensure that
michael@0:        // our data is not overwritten prematurely.
michael@0:        this._parent = parent;
michael@0:        let path = Path.join(this._parent, name);
michael@0: 
michael@0:        SysAll.AbstractEntry.call(this, isDir, isSymLink, name, path);
michael@0:      };
michael@0:      File.DirectoryIterator.Entry.prototype = Object.create(SysAll.AbstractEntry.prototype);
michael@0: 
michael@0:      /**
michael@0:       * Return a version of an instance of
michael@0:       * File.DirectoryIterator.Entry that can be sent from a worker
michael@0:       * thread to the main thread. Note that deserialization is
michael@0:       * asymmetric and returns an object with a different
michael@0:       * implementation.
michael@0:       */
michael@0:      File.DirectoryIterator.Entry.toMsg = function toMsg(value) {
michael@0:        if (!value instanceof File.DirectoryIterator.Entry) {
michael@0:          throw new TypeError("parameter of " +
michael@0:            "File.DirectoryIterator.Entry.toMsg must be a " +
michael@0:            "File.DirectoryIterator.Entry");
michael@0:        }
michael@0:        let serialized = {};
michael@0:        for (let key in File.DirectoryIterator.Entry.prototype) {
michael@0:          serialized[key] = value[key];
michael@0:        }
michael@0:        return serialized;
michael@0:      };
michael@0: 
michael@0:      let gStatData = new Type.stat.implementation();
michael@0:      let gStatDataPtr = gStatData.address();
michael@0:      let gTimevals = new Type.timevals.implementation();
michael@0:      let gTimevalsPtr = gTimevals.address();
michael@0:      let MODE_MASK = 4095 /*= 07777*/;
michael@0:      File.Info = function Info(stat, path) {
michael@0:        let isDir = (stat.st_mode & Const.S_IFMT) == Const.S_IFDIR;
michael@0:        let isSymLink = (stat.st_mode & Const.S_IFMT) == Const.S_IFLNK;
michael@0:        let size = Type.off_t.importFromC(stat.st_size);
michael@0: 
michael@0:        let lastAccessDate = new Date(stat.st_atime * 1000);
michael@0:        let lastModificationDate = new Date(stat.st_mtime * 1000);
michael@0:        let unixLastStatusChangeDate = new Date(stat.st_ctime * 1000);
michael@0: 
michael@0:        let unixOwner = Type.uid_t.importFromC(stat.st_uid);
michael@0:        let unixGroup = Type.gid_t.importFromC(stat.st_gid);
michael@0:        let unixMode = Type.mode_t.importFromC(stat.st_mode & MODE_MASK);
michael@0: 
michael@0:        SysAll.AbstractInfo.call(this, path, isDir, isSymLink, size,
michael@0:            lastAccessDate, lastModificationDate, unixLastStatusChangeDate,
michael@0:            unixOwner, unixGroup, unixMode);
michael@0: 
michael@0:        // Some platforms (e.g. MacOS X, some BSDs) store a file creation date
michael@0:        if ("OSFILE_OFFSETOF_STAT_ST_BIRTHTIME" in Const) {
michael@0:          let date = new Date(stat.st_birthtime * 1000);
michael@0: 
michael@0:         /**
michael@0:          * The date of creation of this file.
michael@0:          *
michael@0:          * Note that the date returned by this method is not always
michael@0:          * reliable. Not all file systems are able to provide this
michael@0:          * information.
michael@0:          *
michael@0:          * @type {Date}
michael@0:          */
michael@0:          this.macBirthDate = date;
michael@0:        }
michael@0:      };
michael@0:      File.Info.prototype = Object.create(SysAll.AbstractInfo.prototype);
michael@0: 
michael@0:      // Deprecated, use macBirthDate/winBirthDate instead
michael@0:      Object.defineProperty(File.Info.prototype, "creationDate", {
michael@0:       get: function creationDate() {
michael@0:         // On the Macintosh, returns the birth date if available.
michael@0:         // On other Unix, as the birth date is not available,
michael@0:         // returns the epoch.
michael@0:         return this.macBirthDate || new Date(0);
michael@0:       }
michael@0:      });
michael@0: 
michael@0:      /**
michael@0:       * Return a version of an instance of File.Info that can be sent
michael@0:       * from a worker thread to the main thread. Note that deserialization
michael@0:       * is asymmetric and returns an object with a different implementation.
michael@0:       */
michael@0:      File.Info.toMsg = function toMsg(stat) {
michael@0:        if (!stat instanceof File.Info) {
michael@0:          throw new TypeError("parameter of File.Info.toMsg must be a File.Info");
michael@0:        }
michael@0:        let serialized = {};
michael@0:        for (let key in File.Info.prototype) {
michael@0:          serialized[key] = stat[key];
michael@0:        }
michael@0:        return serialized;
michael@0:      };
michael@0: 
michael@0:      /**
michael@0:       * Fetch the information on a file.
michael@0:       *
michael@0:       * @param {string} path The full name of the file to open.
michael@0:       * @param {*=} options Additional options. In this implementation:
michael@0:       *
michael@0:       * - {bool} unixNoFollowingLinks If set and |true|, if |path|
michael@0:       * represents a symbolic link, the call will return the information
michael@0:       * of the link itself, rather than that of the target file.
michael@0:       *
michael@0:       * @return {File.Information}
michael@0:       */
michael@0:      File.stat = function stat(path, options = {}) {
michael@0:        if (options.unixNoFollowingLinks) {
michael@0:          throw_on_negative("stat", UnixFile.lstat(path, gStatDataPtr), path);
michael@0:        } else {
michael@0:          throw_on_negative("stat", UnixFile.stat(path, gStatDataPtr), path);
michael@0:        }
michael@0:        return new File.Info(gStatData, path);
michael@0:      };
michael@0: 
michael@0:      /**
michael@0:       * Set the file's access permissions.  Without any options, the
michael@0:       * permissions are set to an approximation of what they would
michael@0:       * have been if the file had been created in its current
michael@0:       * directory in the "most typical" fashion for the operating
michael@0:       * system.  In the current implementation, this means we set
michael@0:       * the POSIX file mode to (0666 & ~umask).
michael@0:       *
michael@0:       * This operation is likely to fail if applied to a file that was
michael@0:       * not created by the currently running program (more precisely,
michael@0:       * if it was created by a program running under a different OS-level
michael@0:       * user account).  It may also fail, or silently do nothing, if the
michael@0:       * filesystem containing the file does not support access permissions.
michael@0:       *
michael@0:       * @param {string} path   The name of the file to reset the permissions of.
michael@0:       * @param {*=} options
michael@0:       * - {number} unixMode     If present, the POSIX file mode is set to
michael@0:       *                         exactly this value, unless |unixHonorUmask| is
michael@0:       *                         also present.
michael@0:       * - {bool} unixHonorUmask If true, any |unixMode| value is modified by
michael@0:       *                         the process umask, as open() would have done.
michael@0:       */
michael@0:      File.setPermissions = function setPermissions(path, options = {}) {
michael@0:        throw_on_negative("setPermissions",
michael@0:                          UnixFile.chmod(path, unixMode(options)),
michael@0:                          path);
michael@0:      };
michael@0: 
michael@0:      /**
michael@0:       * Set the last access and modification date of the file.
michael@0:       * The time stamp resolution is 1 second at best, but might be worse
michael@0:       * depending on the platform.
michael@0:       *
michael@0:       * @param {string} path The full name of the file to set the dates for.
michael@0:       * @param {Date,number=} accessDate The last access date. If numeric,
michael@0:       * milliseconds since epoch. If omitted or null, then the current date
michael@0:       * will be used.
michael@0:       * @param {Date,number=} modificationDate The last modification date. If
michael@0:       * numeric, milliseconds since epoch. If omitted or null, then the current
michael@0:       * date will be used.
michael@0:       *
michael@0:       * @throws {TypeError} In case of invalid paramters.
michael@0:       * @throws {OS.File.Error} In case of I/O error.
michael@0:       */
michael@0:      File.setDates = function setDates(path, accessDate, modificationDate) {
michael@0:        accessDate = normalizeDate("File.setDates", accessDate);
michael@0:        modificationDate = normalizeDate("File.setDates", modificationDate);
michael@0:        gTimevals[0].tv_sec = (accessDate / 1000) | 0;
michael@0:        gTimevals[0].tv_usec = 0;
michael@0:        gTimevals[1].tv_sec = (modificationDate / 1000) | 0;
michael@0:        gTimevals[1].tv_usec = 0;
michael@0:        throw_on_negative("setDates",
michael@0:                          UnixFile.utimes(path, gTimevalsPtr),
michael@0:                          path);
michael@0:      };
michael@0: 
michael@0:      File.read = exports.OS.Shared.AbstractFile.read;
michael@0:      File.writeAtomic = exports.OS.Shared.AbstractFile.writeAtomic;
michael@0:      File.openUnique = exports.OS.Shared.AbstractFile.openUnique;
michael@0:      File.makeDir = exports.OS.Shared.AbstractFile.makeDir;
michael@0: 
michael@0:      /**
michael@0:       * Remove an existing directory and its contents.
michael@0:       *
michael@0:       * @param {string} path The name of the directory.
michael@0:       * @param {*=} options Additional options.
michael@0:       *   - {bool} ignoreAbsent If |false|, throw an error if the directory doesn't
michael@0:       *     exist. |true| by default.
michael@0:       *   - {boolean} ignorePermissions If |true|, remove the file even when lacking write
michael@0:       *     permission.
michael@0:       *
michael@0:       * @throws {OS.File.Error} In case of I/O error, in particular if |path| is
michael@0:       *         not a directory.
michael@0:       *
michael@0:       * Note: This function will remove a symlink even if it points a directory.
michael@0:       */
michael@0:      File.removeDir = function(path, options) {
michael@0:        let isSymLink;
michael@0:        try {
michael@0:          let info = File.stat(path, {unixNoFollowingLinks: true});
michael@0:          isSymLink = info.isSymLink;
michael@0:        } catch (e) {
michael@0:          if ((!("ignoreAbsent" in options) || options.ignoreAbsent) &&
michael@0:              ctypes.errno == Const.ENOENT) {
michael@0:            return;
michael@0:          }
michael@0:          throw e;
michael@0:        }
michael@0:        if (isSymLink) {
michael@0:          // A Unix symlink itself is not a directory even if it points
michael@0:          // a directory.
michael@0:          File.remove(path, options);
michael@0:          return;
michael@0:        }
michael@0:        exports.OS.Shared.AbstractFile.removeRecursive(path, options);
michael@0:      };
michael@0: 
michael@0:      /**
michael@0:       * Get the current directory by getCurrentDirectory.
michael@0:       */
michael@0:      File.getCurrentDirectory = function getCurrentDirectory() {
michael@0:        let path = UnixFile.get_current_dir_name?UnixFile.get_current_dir_name():
michael@0:          UnixFile.getwd_auto(null);
michael@0:        throw_on_null("getCurrentDirectory", path);
michael@0:        return path.readString();
michael@0:      };
michael@0: 
michael@0:      /**
michael@0:       * Set the current directory by setCurrentDirectory.
michael@0:       */
michael@0:      File.setCurrentDirectory = function setCurrentDirectory(path) {
michael@0:        throw_on_negative("setCurrentDirectory",
michael@0:          UnixFile.chdir(path),
michael@0:          path
michael@0:        );
michael@0:      };
michael@0: 
michael@0:      /**
michael@0:       * Get/set the current directory.
michael@0:       */
michael@0:      Object.defineProperty(File, "curDir", {
michael@0:          set: function(path) {
michael@0:            this.setCurrentDirectory(path);
michael@0:          },
michael@0:          get: function() {
michael@0:            return this.getCurrentDirectory();
michael@0:          }
michael@0:        }
michael@0:      );
michael@0: 
michael@0:      // Utility functions
michael@0: 
michael@0:      /**
michael@0:       * Turn the result of |open| into an Error or a File
michael@0:       * @param {number} maybe The result of the |open| operation that may
michael@0:       * represent either an error or a success. If -1, this function raises
michael@0:       * an error holding ctypes.errno, otherwise it returns the opened file.
michael@0:       * @param {string=} path The path of the file.
michael@0:       */
michael@0:      function error_or_file(maybe, path) {
michael@0:        if (maybe == -1) {
michael@0:          throw new File.Error("open", ctypes.errno, path);
michael@0:        }
michael@0:        return new File(maybe, path);
michael@0:      }
michael@0: 
michael@0:      /**
michael@0:       * Utility function to sort errors represented as "-1" from successes.
michael@0:       *
michael@0:       * @param {string=} operation The name of the operation. If unspecified,
michael@0:       * the name of the caller function.
michael@0:       * @param {number} result The result of the operation that may
michael@0:       * represent either an error or a success. If -1, this function raises
michael@0:       * an error holding ctypes.errno, otherwise it returns |result|.
michael@0:       * @param {string=} path The path of the file.
michael@0:       */
michael@0:      function throw_on_negative(operation, result, path) {
michael@0:        if (result < 0) {
michael@0:          throw new File.Error(operation, ctypes.errno, path);
michael@0:        }
michael@0:        return result;
michael@0:      }
michael@0: 
michael@0:      /**
michael@0:       * Utility function to sort errors represented as |null| from successes.
michael@0:       *
michael@0:       * @param {string=} operation The name of the operation. If unspecified,
michael@0:       * the name of the caller function.
michael@0:       * @param {pointer} result The result of the operation that may
michael@0:       * represent either an error or a success. If |null|, this function raises
michael@0:       * an error holding ctypes.errno, otherwise it returns |result|.
michael@0:       * @param {string=} path The path of the file.
michael@0:       */
michael@0:      function throw_on_null(operation, result, path) {
michael@0:        if (result == null || (result.isNull && result.isNull())) {
michael@0:          throw new File.Error(operation, ctypes.errno, path);
michael@0:        }
michael@0:        return result;
michael@0:      }
michael@0: 
michael@0:      /**
michael@0:       * Normalize and verify a Date or numeric date value.
michael@0:       *
michael@0:       * @param {string} fn Function name of the calling function.
michael@0:       * @param {Date,number} date The date to normalize. If omitted or null,
michael@0:       * then the current date will be used.
michael@0:       *
michael@0:       * @throws {TypeError} Invalid date provided.
michael@0:       *
michael@0:       * @return {number} Sanitized, numeric date in milliseconds since epoch.
michael@0:       */
michael@0:      function normalizeDate(fn, date) {
michael@0:        if (typeof date !== "number" && !date) {
michael@0:          // |date| was Omitted or null.
michael@0:          date = Date.now();
michael@0:        } else if (typeof date.getTime === "function") {
michael@0:          // Input might be a date or date-like object.
michael@0:          date = date.getTime();
michael@0:        }
michael@0: 
michael@0:        if (isNaN(date)) {
michael@0:          throw new TypeError("|date| parameter of " + fn + " must be a " +
michael@0:                              "|Date| instance or number");
michael@0:        }
michael@0:        return date;
michael@0:      };
michael@0: 
michael@0:      /**
michael@0:       * Helper used by both versions of setPermissions.
michael@0:       */
michael@0:      function unixMode(options) {
michael@0:        let mode = 438; /* 0666 */
michael@0:        let unixHonorUmask = true;
michael@0:        if ("unixMode" in options) {
michael@0:          unixHonorUmask = false;
michael@0:          mode = options.unixMode;
michael@0:        }
michael@0:        if ("unixHonorUmask" in options) {
michael@0:          unixHonorUmask = options.unixHonorUmask;
michael@0:        }
michael@0:        if (unixHonorUmask) {
michael@0:          mode &= ~SharedAll.Constants.Sys.umask;
michael@0:        }
michael@0:        return mode;
michael@0:      }
michael@0: 
michael@0:      File.Unix = exports.OS.Unix.File;
michael@0:      File.Error = SysAll.Error;
michael@0:      exports.OS.File = File;
michael@0:      exports.OS.Shared.Type = Type;
michael@0: 
michael@0:      Object.defineProperty(File, "POS_START", { value: SysAll.POS_START });
michael@0:      Object.defineProperty(File, "POS_CURRENT", { value: SysAll.POS_CURRENT });
michael@0:      Object.defineProperty(File, "POS_END", { value: SysAll.POS_END });
michael@0:    })(this);
michael@0: }