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:  * Windows 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_win_front.jsm to be used directly as a main thread
michael@0:     // module yet.
michael@0:     throw new Error("osfile_win_front.jsm cannot be used from the main thread yet");
michael@0:   }
michael@0: 
michael@0:   (function(exports) {
michael@0:      "use strict";
michael@0: 
michael@0: 
michael@0:       // exports.OS.Win is created by osfile_win_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_win_allthreads.jsm");
michael@0:      exports.OS.Win.File._init();
michael@0:      let Const = exports.OS.Constants.Win;
michael@0:      let WinFile = exports.OS.Win.File;
michael@0:      let Type = WinFile.Type;
michael@0: 
michael@0:      // Mutable thread-global data
michael@0:      // In the Windows implementation, methods |read| and |write|
michael@0:      // require passing a pointer to an uint32 to determine how many
michael@0:      // bytes have been read/written. In C, this is a benigne operation,
michael@0:      // but in js-ctypes, this has a cost. Rather than re-allocating a
michael@0:      // C uint32 and a C uint32* for each |read|/|write|, we take advantage
michael@0:      // of the fact that the state is thread-private -- hence that two
michael@0:      // |read|/|write| operations cannot take place at the same time --
michael@0:      // and we use the following global mutable values:
michael@0:      let gBytesRead = new ctypes.uint32_t(0);
michael@0:      let gBytesReadPtr = gBytesRead.address();
michael@0:      let gBytesWritten = new ctypes.uint32_t(0);
michael@0:      let gBytesWrittenPtr = gBytesWritten.address();
michael@0: 
michael@0:      // Same story for GetFileInformationByHandle
michael@0:      let gFileInfo = new Type.FILE_INFORMATION.implementation();
michael@0:      let gFileInfoPtr = gFileInfo.address();
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 = WinFile._CloseHandle(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.winLastError, 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:        // |gBytesReadPtr| is a pointer to |gBytesRead|.
michael@0:        throw_on_zero("read",
michael@0:          WinFile.ReadFile(this.fd, buffer, nbytes, gBytesReadPtr, null),
michael@0:          this._path
michael@0:        );
michael@0:        return gBytesRead.value;
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:        if (this._appendMode) {
michael@0:          // Need to manually seek on Windows, as O_APPEND is not supported.
michael@0:          // This is, of course, a race, but there is no real way around this.
michael@0:          this.setPosition(0, File.POS_END);
michael@0:        }
michael@0:        // |gBytesWrittenPtr| is a pointer to |gBytesWritten|.
michael@0:        throw_on_zero("write",
michael@0:          WinFile.WriteFile(this.fd, buffer, nbytes, gBytesWrittenPtr, null),
michael@0:          this._path
michael@0:        );
michael@0:        return gBytesWritten.value;
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.FILE_BEGIN;
michael@0:        }
michael@0:        let pos64 = ctypes.Int64(pos);
michael@0:        // Per MSDN, while |lDistanceToMove| (low) is declared as int32_t, when
michael@0:        // providing |lDistanceToMoveHigh| as well, it should countain the
michael@0:        // bottom 32 bits of the 64-bit integer. Hence the following |posLo|
michael@0:        // cast is OK.
michael@0:        let posLo = new ctypes.uint32_t(ctypes.Int64.lo(pos64));
michael@0:        posLo = ctypes.cast(posLo, ctypes.int32_t);
michael@0:        let posHi = new ctypes.int32_t(ctypes.Int64.hi(pos64));
michael@0:        let result = WinFile.SetFilePointer(
michael@0:          this.fd, posLo.value, posHi.address(), whence);
michael@0:        // INVALID_SET_FILE_POINTER might be still a valid result, as it
michael@0:        // represents the lower 32 bit of the int64 result. MSDN says to check
michael@0:        // both, INVALID_SET_FILE_POINTER and a non-zero winLastError.
michael@0:        if (result == Const.INVALID_SET_FILE_POINTER && ctypes.winLastError) {
michael@0:          throw new File.Error("setPosition", ctypes.winLastError, this._path);
michael@0:        }
michael@0:        pos64 = ctypes.Int64.join(posHi.value, result);
michael@0:        return Type.int64_t.project(pos64);
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_zero("stat",
michael@0:          WinFile.GetFileInformationByHandle(this.fd, gFileInfoPtr),
michael@0:          this._path);
michael@0:        return new File.Info(gFileInfo, 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 = Date_to_FILETIME("File.prototype.setDates", accessDate, this._path);
michael@0:        modificationDate = Date_to_FILETIME("File.prototype.setDates",
michael@0:                                            modificationDate,
michael@0:                                            this._path);
michael@0:        throw_on_zero("setDates",
michael@0:                      WinFile.SetFileTime(this.fd, null, accessDate.address(),
michael@0:                                          modificationDate.address()),
michael@0:                      this._path);
michael@0:      };
michael@0: 
michael@0:      /**
michael@0:       * Set the file's access permission bits.
michael@0:       * Not implemented for Windows (bug 1022816).
michael@0:       */
michael@0:      File.prototype.setPermissions = function setPermissions(options = {}) {
michael@0:          // do nothing
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_zero("flush", WinFile.FlushFileBuffers(this.fd), this._path);
michael@0:      };
michael@0: 
michael@0:      // The default sharing mode for opening files: files are not
michael@0:      // locked against being reopened for reading/writing or against
michael@0:      // being deleted by the same process or another process.
michael@0:      // This is consistent with the default Unix policy.
michael@0:      const DEFAULT_SHARE = Const.FILE_SHARE_READ |
michael@0:        Const.FILE_SHARE_WRITE | Const.FILE_SHARE_DELETE;
michael@0: 
michael@0:      // The default flags for opening files.
michael@0:      const DEFAULT_FLAGS = Const.FILE_ATTRIBUTE_NORMAL;
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} winShare If specified, a share mode, as per
michael@0:       * Windows function |CreateFile|. You can build it from
michael@0:       * constants |OS.Constants.Win.FILE_SHARE_*|. If unspecified,
michael@0:       * the file uses the default sharing policy: it can be opened
michael@0:       * for reading and/or writing and it can be removed by other
michael@0:       * processes and by the same process.
michael@0:       * - {number} winSecurity If specified, Windows security
michael@0:       * attributes, as per Windows function |CreateFile|. If unspecified,
michael@0:       * no security attributes.
michael@0:       * - {number} winAccess If specified, Windows access mode, as
michael@0:       * per Windows function |CreateFile|. This also requires option
michael@0:       * |winDisposition| and this replaces argument |mode|. If unspecified,
michael@0:       * uses the string |mode|.
michael@0:       * - {number} winDisposition If specified, Windows disposition mode,
michael@0:       * as per Windows function |CreateFile|. This also requires option
michael@0:       * |winAccess| and this replaces argument |mode|. If unspecified,
michael@0:       * uses the string |mode|.
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 Win_open(path, mode = {}, options = {}) {
michael@0:        let share = options.winShare !== undefined ? options.winShare : DEFAULT_SHARE;
michael@0:        let security = options.winSecurity || null;
michael@0:        let flags = options.winFlags !== undefined ? options.winFlags : DEFAULT_FLAGS;
michael@0:        let template = options.winTemplate ? options.winTemplate._fd : null;
michael@0:        let access;
michael@0:        let disposition;
michael@0: 
michael@0:        mode = OS.Shared.AbstractFile.normalizeOpenMode(mode);
michael@0: 
michael@0:        if ("winAccess" in options && "winDisposition" in options) {
michael@0:          access = options.winAccess;
michael@0:          disposition = options.winDisposition;
michael@0:        } else if (("winAccess" in options && !("winDisposition" in options))
michael@0:                  ||(!("winAccess" in options) && "winDisposition" in options)) {
michael@0:          throw new TypeError("OS.File.open requires either both options " +
michael@0:            "winAccess and winDisposition or neither");
michael@0:        } else {
michael@0:          if (mode.read) {
michael@0:            access |= Const.GENERIC_READ;
michael@0:          }
michael@0:          if (mode.write) {
michael@0:            access |= Const.GENERIC_WRITE;
michael@0:          }
michael@0:          // Finally, handle create/existing/trunc
michael@0:          if (mode.trunc) {
michael@0:            if (mode.existing) {
michael@0:              // It seems that Const.TRUNCATE_EXISTING is broken
michael@0:              // in presence of links (source, anyone?). We need
michael@0:              // to open normally, then perform truncation manually.
michael@0:              disposition = Const.OPEN_EXISTING;
michael@0:            } else {
michael@0:              disposition = Const.CREATE_ALWAYS;
michael@0:            }
michael@0:          } else if (mode.create) {
michael@0:            disposition = Const.CREATE_NEW;
michael@0:          } else if (mode.read && !mode.write) {
michael@0:            disposition = Const.OPEN_EXISTING;
michael@0:          } else if (mode.existing) {
michael@0:            disposition = Const.OPEN_EXISTING;
michael@0:          } else {
michael@0:            disposition = Const.OPEN_ALWAYS;
michael@0:          }
michael@0:        }
michael@0: 
michael@0:        let file = error_or_file(WinFile.CreateFile(path,
michael@0:          access, share, security, disposition, flags, template), path);
michael@0: 
michael@0:        file._appendMode = !!mode.append;
michael@0: 
michael@0:        if (!(mode.trunc && mode.existing)) {
michael@0:          return file;
michael@0:        }
michael@0:        // Now, perform manual truncation
michael@0:        file.setPosition(0, File.POS_START);
michael@0:        throw_on_zero("open",
michael@0:          WinFile.SetEndOfFile(file.fd),
michael@0:          path);
michael@0:        return file;
michael@0:      };
michael@0: 
michael@0:      /**
michael@0:       * Checks if a file or directory 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 Win_exists(path) {
michael@0:        try {
michael@0:          let file = File.open(path, FILE_STAT_MODE, FILE_STAT_OPTIONS);
michael@0:          file.close();
michael@0:          return true;
michael@0:        } catch (x) {
michael@0:          return false;
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:        if (WinFile.DeleteFile(path)) {
michael@0:          return;
michael@0:        }
michael@0: 
michael@0:        if (ctypes.winLastError == Const.ERROR_FILE_NOT_FOUND) {
michael@0:          if ((!("ignoreAbsent" in options) || options.ignoreAbsent)) {
michael@0:            return;
michael@0:          }
michael@0:        } else if (ctypes.winLastError == Const.ERROR_ACCESS_DENIED) {
michael@0:          let attributes = WinFile.GetFileAttributes(path);
michael@0:          if (attributes != Const.INVALID_FILE_ATTRIBUTES &&
michael@0:              attributes & Const.FILE_ATTRIBUTE_READONLY) {
michael@0:            let newAttributes = attributes & ~Const.FILE_ATTRIBUTE_READONLY;
michael@0:            if (WinFile.SetFileAttributes(path, newAttributes) &&
michael@0:                WinFile.DeleteFile(path)) {
michael@0:              return;
michael@0:            }
michael@0:          }
michael@0:        }
michael@0: 
michael@0:        throw new File.Error("remove", ctypes.winLastError, path);
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 = WinFile.RemoveDirectory(path);
michael@0:        if (!result) {
michael@0:          if ((!("ignoreAbsent" in options) || options.ignoreAbsent) &&
michael@0:              ctypes.winLastError == Const.ERROR_FILE_NOT_FOUND) {
michael@0:            return;
michael@0:          }
michael@0:          throw new File.Error("removeEmptyDir", ctypes.winLastError, path);
michael@0:        }
michael@0:      };
michael@0: 
michael@0:      /**
michael@0:       * Create a directory and, optionally, its parent directories.
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:       * - {C pointer} winSecurity If specified, security attributes
michael@0:       * as per winapi function |CreateDirectory|. If unspecified,
michael@0:       * use the default security descriptor, inherited from the
michael@0:       * parent directory.
michael@0:       * - {bool} ignoreExisting If |false|, throw an 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 security = options.winSecurity || null;
michael@0:        let result = WinFile.CreateDirectory(path, security);
michael@0: 
michael@0:        if (result) {
michael@0:          return;
michael@0:        }
michael@0: 
michael@0:        if (("ignoreExisting" in options) && !options.ignoreExisting) {
michael@0:          throw new File.Error("makeDir", ctypes.winLastError, path);
michael@0:        }
michael@0: 
michael@0:        if (ctypes.winLastError == Const.ERROR_ALREADY_EXISTS) {
michael@0:          return;
michael@0:        }
michael@0: 
michael@0:        // If the user has no access, but it's a root directory, no error should be thrown
michael@0:        let splitPath = OS.Path.split(path);
michael@0:        // Removing last component if it's empty
michael@0:        // An empty last component is caused by trailing slashes in path
michael@0:        // This is always the case with root directories
michael@0:        if( splitPath.components[splitPath.components.length - 1].length === 0 ) {
michael@0:          splitPath.components.pop();
michael@0:        }
michael@0:        // One component consisting of a drive letter implies a directory root.
michael@0:        if (ctypes.winLastError == Const.ERROR_ACCESS_DENIED &&
michael@0:            splitPath.winDrive &&
michael@0:            splitPath.components.length === 1 ) {
michael@0:          return;
michael@0:        }
michael@0: 
michael@0:        throw new File.Error("makeDir", ctypes.winLastError, path);
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 true, 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 = function copy(sourcePath, destPath, options = {}) {
michael@0:        throw_on_zero("copy",
michael@0:          WinFile.CopyFile(sourcePath, destPath, options.noOverwrite || false),
michael@0:          sourcePath
michael@0:        );
michael@0:      };
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 drive.
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 = function move(sourcePath, destPath, options = {}) {
michael@0:        let flags = 0;
michael@0:        if (!options.noCopy) {
michael@0:          flags = Const.MOVEFILE_COPY_ALLOWED;
michael@0:        }
michael@0:        if (!options.noOverwrite) {
michael@0:          flags = flags | Const.MOVEFILE_REPLACE_EXISTING;
michael@0:        }
michael@0:        throw_on_zero("move",
michael@0:          WinFile.MoveFileEx(sourcePath, destPath, flags),
michael@0:          sourcePath
michael@0:        );
michael@0: 
michael@0:        // Inherit NTFS permissions from the destination directory
michael@0:        // if possible.
michael@0:        if (Path.dirname(sourcePath) === Path.dirname(destPath)) {
michael@0:          // Skip if the move operation was the simple rename,
michael@0:          return;
michael@0:        }
michael@0:        // The function may fail for various reasons (e.g. not all
michael@0:        // filesystems support NTFS permissions or the user may not
michael@0:        // have the enough rights to read/write permissions).
michael@0:        // However we can safely ignore errors. The file was already
michael@0:        // moved. Setting permissions is not mandatory.
michael@0:        let dacl = new ctypes.voidptr_t();
michael@0:        let sd = new ctypes.voidptr_t();
michael@0:        WinFile.GetNamedSecurityInfo(destPath, Const.SE_FILE_OBJECT,
michael@0:                                     Const.DACL_SECURITY_INFORMATION,
michael@0:                                     null /*sidOwner*/, null /*sidGroup*/,
michael@0:                                     dacl.address(), null /*sacl*/,
michael@0:                                     sd.address());
michael@0:        // dacl will be set only if the function succeeds.
michael@0:        if (!dacl.isNull()) {
michael@0:          WinFile.SetNamedSecurityInfo(destPath, Const.SE_FILE_OBJECT,
michael@0:                                       Const.DACL_SECURITY_INFORMATION |
michael@0:                                       Const.UNPROTECTED_DACL_SECURITY_INFORMATION,
michael@0:                                       null /*sidOwner*/, null /*sidGroup*/,
michael@0:                                       dacl, null /*sacl*/);
michael@0:        }
michael@0:        // sd will be set only if the function succeeds.
michael@0:        if (!sd.isNull()) {
michael@0:            WinFile.LocalFree(Type.HLOCAL.cast(sd));
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 Win_getAvailableFreeSpace(sourcePath) {
michael@0:        let freeBytesAvailableToUser = new Type.uint64_t.implementation(0);
michael@0:        let freeBytesAvailableToUserPtr = freeBytesAvailableToUser.address();
michael@0: 
michael@0:        throw_on_zero("getAvailableFreeSpace",
michael@0:          WinFile.GetDiskFreeSpaceEx(sourcePath, freeBytesAvailableToUserPtr, null, null)
michael@0:        );
michael@0: 
michael@0:        return freeBytesAvailableToUser.value;
michael@0:      };
michael@0: 
michael@0:      /**
michael@0:       * A global value used to receive data during time conversions.
michael@0:       */
michael@0:      let gSystemTime = new Type.SystemTime.implementation();
michael@0:      let gSystemTimePtr = gSystemTime.address();
michael@0: 
michael@0:      /**
michael@0:       * Utility function: convert a FILETIME to a JavaScript Date.
michael@0:       */
michael@0:      let FILETIME_to_Date = function FILETIME_to_Date(fileTime, path) {
michael@0:        if (fileTime == null) {
michael@0:          throw new TypeError("Expecting a non-null filetime");
michael@0:        }
michael@0:        throw_on_zero("FILETIME_to_Date",
michael@0:                      WinFile.FileTimeToSystemTime(fileTime.address(),
michael@0:                                                   gSystemTimePtr),
michael@0:                      path);
michael@0:        // Windows counts hours, minutes, seconds from UTC,
michael@0:        // JS counts from local time, so we need to go through UTC.
michael@0:        let utc = Date.UTC(gSystemTime.wYear,
michael@0:                           gSystemTime.wMonth - 1
michael@0:                           /*Windows counts months from 1, JS from 0*/,
michael@0:                           gSystemTime.wDay, gSystemTime.wHour,
michael@0:                           gSystemTime.wMinute, gSystemTime.wSecond,
michael@0:                           gSystemTime.wMilliSeconds);
michael@0:        return new Date(utc);
michael@0:      };
michael@0: 
michael@0:      /**
michael@0:       * Utility function: convert Javascript Date to FileTime.
michael@0:       *
michael@0:       * @param {string} fn Name of the calling function.
michael@0:       * @param {Date,number} date The date to be converted. If omitted or null,
michael@0:       * then the current date will be used. If numeric, assumed to be the date
michael@0:       * in milliseconds since epoch.
michael@0:       */
michael@0:      let Date_to_FILETIME = function Date_to_FILETIME(fn, date, path) {
michael@0:        if (typeof date === "number") {
michael@0:          date = new Date(date);
michael@0:        } else if (!date) {
michael@0:          date = new Date();
michael@0:        } else if (typeof date.getUTCFullYear !== "function") {
michael@0:          throw new TypeError("|date| parameter of " + fn + " must be a " +
michael@0:                              "|Date| instance or number");
michael@0:        }
michael@0:        gSystemTime.wYear = date.getUTCFullYear();
michael@0:        // Windows counts months from 1, JS from 0.
michael@0:        gSystemTime.wMonth = date.getUTCMonth() + 1;
michael@0:        gSystemTime.wDay = date.getUTCDate();
michael@0:        gSystemTime.wHour = date.getUTCHours();
michael@0:        gSystemTime.wMinute = date.getUTCMinutes();
michael@0:        gSystemTime.wSecond = date.getUTCSeconds();
michael@0:        gSystemTime.wMilliseconds = date.getUTCMilliseconds();
michael@0:        let result = new OS.Shared.Type.FILETIME.implementation();
michael@0:        throw_on_zero("Date_to_FILETIME",
michael@0:                      WinFile.SystemTimeToFileTime(gSystemTimePtr,
michael@0:                                                   result.address()),
michael@0:                      path);
michael@0:        return result;
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 An object that may contain the following field:
michael@0:       * @option {string} winPattern Windows file name pattern; if set,
michael@0:       * only files matching this pattern are returned.
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:        if (options && options.winPattern) {
michael@0:          this._pattern = path + "\\" + options.winPattern;
michael@0:        } else {
michael@0:          this._pattern = path + "\\*";
michael@0:        }
michael@0:        this._path = path;
michael@0: 
michael@0:        // Pre-open the first item.
michael@0:        this._first = true;
michael@0:        this._findData = new Type.FindData.implementation();
michael@0:        this._findDataPtr = this._findData.address();
michael@0:        this._handle = WinFile.FindFirstFile(this._pattern, this._findDataPtr);
michael@0:        if (this._handle == Const.INVALID_HANDLE_VALUE) {
michael@0:          let error = ctypes.winLastError;
michael@0:          this._findData = null;
michael@0:          this._findDataPtr = null;
michael@0:          if (error == Const.ERROR_FILE_NOT_FOUND) {
michael@0:            // Directory is empty, let's behave as if it were closed
michael@0:            SharedAll.LOG("Directory is empty");
michael@0:            this._closed = true;
michael@0:            this._exists = true;
michael@0:          } else if (error == Const.ERROR_PATH_NOT_FOUND) {
michael@0:            // Directory does not exist, let's throw if we attempt to walk it
michael@0:            SharedAll.LOG("Directory does not exist");
michael@0:            this._closed = true;
michael@0:            this._exists = false;
michael@0:          } else {
michael@0:            throw new File.Error("DirectoryIterator", error, this._path);
michael@0:          }
michael@0:        } else {
michael@0:          this._closed = false;
michael@0:          this._exists = true;
michael@0:        }
michael@0:      };
michael@0: 
michael@0:      File.DirectoryIterator.prototype = Object.create(exports.OS.Shared.AbstractFile.AbstractIterator.prototype);
michael@0: 
michael@0: 
michael@0:      /**
michael@0:       * Fetch the next entry in the directory.
michael@0:       *
michael@0:       * @return null If we have reached the end of the directory.
michael@0:       */
michael@0:      File.DirectoryIterator.prototype._next = function _next() {
michael@0:        // Bailout if the directory does not exist
michael@0:        if (!this._exists) {
michael@0:          throw File.Error.noSuchFile("DirectoryIterator.prototype.next", this._path);
michael@0:        }
michael@0:        // Bailout if the iterator is closed.
michael@0:        if (this._closed) {
michael@0:          return null;
michael@0:        }
michael@0:        // If this is the first entry, we have obtained it already
michael@0:        // during construction.
michael@0:        if (this._first) {
michael@0:          this._first = false;
michael@0:          return this._findData;
michael@0:        }
michael@0: 
michael@0:        if (WinFile.FindNextFile(this._handle, this._findDataPtr)) {
michael@0:          return this._findData;
michael@0:        } else {
michael@0:          let error = ctypes.winLastError;
michael@0:          this.close();
michael@0:          if (error == Const.ERROR_NO_MORE_FILES) {
michael@0:             return null;
michael@0:          } else {
michael@0:             throw new File.Error("iter (FindNextFile)", error, this._path);
michael@0:          }
michael@0:        }
michael@0:      },
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:          // FIXME: If we start supporting "\\?\"-prefixed paths, do not forget
michael@0:          // that "." and ".." are absolutely normal file names if _path starts
michael@0:          // with such prefix
michael@0:          for (let entry = this._next(); entry != null; entry = this._next()) {
michael@0:            let name = entry.cFileName.readString();
michael@0:            if (name == "." || name == "..") {
michael@0:              continue;
michael@0:            }
michael@0:            return new File.DirectoryIterator.Entry(entry, this._path);
michael@0:          }
michael@0:          throw StopIteration;
michael@0:      };
michael@0: 
michael@0:      File.DirectoryIterator.prototype.close = function close() {
michael@0:        if (this._closed) {
michael@0:          return;
michael@0:        }
michael@0:        this._closed = true;
michael@0:        if (this._handle) {
michael@0:          // We might not have a handle if the iterator is closed
michael@0:          // before being used.
michael@0:          throw_on_zero("FindClose",
michael@0:            WinFile.FindClose(this._handle),
michael@0:            this._path);
michael@0:          this._handle = null;
michael@0:        }
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:      File.DirectoryIterator.Entry = function Entry(win_entry, parent) {
michael@0:        if (!win_entry.dwFileAttributes || !win_entry.ftCreationTime ||
michael@0:            !win_entry.ftLastAccessTime || !win_entry.ftLastWriteTime)
michael@0:         throw new TypeError();
michael@0: 
michael@0:        // Copy the relevant part of |win_entry| to ensure that
michael@0:        // our data is not overwritten prematurely.
michael@0:        let isDir = !!(win_entry.dwFileAttributes & Const.FILE_ATTRIBUTE_DIRECTORY);
michael@0:        let isSymLink = !!(win_entry.dwFileAttributes & Const.FILE_ATTRIBUTE_REPARSE_POINT);
michael@0: 
michael@0:        let winCreationDate = FILETIME_to_Date(win_entry.ftCreationTime, this._path);
michael@0:        let winLastWriteDate = FILETIME_to_Date(win_entry.ftLastWriteTime, this._path);
michael@0:        let winLastAccessDate = FILETIME_to_Date(win_entry.ftLastAccessTime, this._path);
michael@0: 
michael@0:        let name = win_entry.cFileName.readString();
michael@0:        if (!name) {
michael@0:          throw new TypeError("Empty name");
michael@0:        }
michael@0: 
michael@0:        if (!parent) {
michael@0:          throw new TypeError("Empty parent");
michael@0:        }
michael@0:        this._parent = parent;
michael@0: 
michael@0:        let path = Path.join(this._parent, name);
michael@0: 
michael@0:        SysAll.AbstractEntry.call(this, isDir, isSymLink, name,
michael@0:          winCreationDate, winLastWriteDate,
michael@0:          winLastAccessDate, 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: 
michael@0:      /**
michael@0:       * Information on a file.
michael@0:       *
michael@0:       * To obtain the latest information on a file, use |File.stat|
michael@0:       * (for an unopened file) or |File.prototype.stat| (for an
michael@0:       * already opened file).
michael@0:       *
michael@0:       * @constructor
michael@0:       */
michael@0:      File.Info = function Info(stat, path) {
michael@0:        let isDir = !!(stat.dwFileAttributes & Const.FILE_ATTRIBUTE_DIRECTORY);
michael@0:        let isSymLink = !!(stat.dwFileAttributes & Const.FILE_ATTRIBUTE_REPARSE_POINT);
michael@0: 
michael@0:        let winBirthDate = FILETIME_to_Date(stat.ftCreationTime, this._path);
michael@0:        let lastAccessDate = FILETIME_to_Date(stat.ftLastAccessTime, this._path);
michael@0:        let lastWriteDate = FILETIME_to_Date(stat.ftLastWriteTime, this._path);
michael@0: 
michael@0:        let value = ctypes.UInt64.join(stat.nFileSizeHigh, stat.nFileSizeLow);
michael@0:        let size = Type.uint64_t.importFromC(value);
michael@0: 
michael@0:        SysAll.AbstractInfo.call(this, path, isDir, isSymLink, size,
michael@0:          winBirthDate, lastAccessDate, lastWriteDate);
michael@0:      };
michael@0:      File.Info.prototype = Object.create(SysAll.AbstractInfo.prototype);
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:      /**
michael@0:       * Fetch the information on a file.
michael@0:       *
michael@0:       * Performance note: if you have opened the file already,
michael@0:       * method |File.prototype.stat| is generally much faster
michael@0:       * than method |File.stat|.
michael@0:       *
michael@0:       * Platform-specific note: under Windows, if the file is
michael@0:       * already opened without sharing of the read capability,
michael@0:       * this function will fail.
michael@0:       *
michael@0:       * @return {File.Information}
michael@0:       */
michael@0:      File.stat = function stat(path) {
michael@0:        let file = File.open(path, FILE_STAT_MODE, FILE_STAT_OPTIONS);
michael@0:        try {
michael@0:          return file.stat();
michael@0:        } finally {
michael@0:          file.close();
michael@0:        }
michael@0:      };
michael@0:      // All of the following is required to ensure that File.stat
michael@0:      // also works on directories.
michael@0:      const FILE_STAT_MODE = {
michael@0:        read: true
michael@0:      };
michael@0:      const FILE_STAT_OPTIONS = {
michael@0:        // Directories can be opened neither for reading(!) nor for writing
michael@0:        winAccess: 0,
michael@0:        // Directories can only be opened with backup semantics(!)
michael@0:        winFlags: Const.FILE_FLAG_BACKUP_SEMANTICS,
michael@0:        winDisposition: Const.OPEN_EXISTING
michael@0:      };
michael@0: 
michael@0:      /**
michael@0:       * Set the file's access permission bits.
michael@0:       * Not implemented for Windows (bug 1022816).
michael@0:       */
michael@0:      File.setPermissions = function setPermissions(path, options = {}) {
michael@0:          // do nothing
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:       * Performance note: if you have opened the file already in write mode,
michael@0:       * method |File.prototype.stat| is generally much faster
michael@0:       * than method |File.stat|.
michael@0:       *
michael@0:       * Platform-specific note: under Windows, if the file is
michael@0:       * already opened without sharing of the write capability,
michael@0:       * this function will fail.
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:        let file = File.open(path, FILE_SETDATES_MODE, FILE_SETDATES_OPTIONS);
michael@0:        try {
michael@0:          return file.setDates(accessDate, modificationDate);
michael@0:        } finally {
michael@0:          file.close();
michael@0:        }
michael@0:      };
michael@0:      // All of the following is required to ensure that File.setDates
michael@0:      // also works on directories.
michael@0:      const FILE_SETDATES_MODE = {
michael@0:        write: true
michael@0:      };
michael@0:      const FILE_SETDATES_OPTIONS = {
michael@0:        winAccess: Const.GENERIC_WRITE,
michael@0:        // Directories can only be opened with backup semantics(!)
michael@0:        winFlags: Const.FILE_FLAG_BACKUP_SEMANTICS,
michael@0:        winDisposition: Const.OPEN_EXISTING
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:      File.removeDir = function(path, options) {
michael@0:        // We can't use File.stat here because it will follow the symlink.
michael@0:        let attributes = WinFile.GetFileAttributes(path);
michael@0:        if (attributes == Const.INVALID_FILE_ATTRIBUTES) {
michael@0:          if ((!("ignoreAbsent" in options) || options.ignoreAbsent) &&
michael@0:              ctypes.winLastError == Const.ERROR_FILE_NOT_FOUND) {
michael@0:            return;
michael@0:          }
michael@0:          throw new File.Error("removeEmptyDir", ctypes.winLastError, path);
michael@0:        }
michael@0:        if (attributes & Const.FILE_ATTRIBUTE_REPARSE_POINT) {
michael@0:          // Unlike Unix symlinks, NTFS junctions or NTFS symlinks to
michael@0:          // directories are directories themselves. OS.File.remove()
michael@0:          // will not work for them.
michael@0:          OS.File.removeEmptyDir(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:        // This function is more complicated than one could hope.
michael@0:        //
michael@0:        // This is due to two facts:
michael@0:        // - the maximal length of a path under Windows is not completely
michael@0:        //  specified (there is a constant MAX_PATH, but it is quite possible
michael@0:        //  to create paths that are much larger, see bug 744413);
michael@0:        // - if we attempt to call |GetCurrentDirectory| with a buffer that
michael@0:        //  is too short, it returns the length of the current directory, but
michael@0:        //  this length might be insufficient by the time we can call again
michael@0:        //  the function with a larger buffer, in the (unlikely but possible)
michael@0:        //  case in which the process changes directory to a directory with
michael@0:        //  a longer name between both calls.
michael@0:        //
michael@0:        let buffer_size = 4096;
michael@0:        while (true) {
michael@0:          let array = new (ctypes.ArrayType(ctypes.jschar, buffer_size))();
michael@0:          let expected_size = throw_on_zero("getCurrentDirectory",
michael@0:            WinFile.GetCurrentDirectory(buffer_size, array)
michael@0:          );
michael@0:          if (expected_size <= buffer_size) {
michael@0:            return array.readString();
michael@0:          }
michael@0:          // At this point, we are in a case in which our buffer was not
michael@0:          // large enough to hold the name of the current directory.
michael@0:          // Consequently, we need to increase the size of the buffer.
michael@0:          // Note that, even in crazy scenarios, the loop will eventually
michael@0:          // converge, as the length of the paths cannot increase infinitely.
michael@0:          buffer_size = expected_size + 1 /* to store \0 */;
michael@0:        }
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_zero("setCurrentDirectory",
michael@0:          WinFile.SetCurrentDirectory(path),
michael@0:          path);
michael@0:      };
michael@0: 
michael@0:      /**
michael@0:       * Get/set the current directory by |curDir|.
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, used for error-handling
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.winLastError, 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 == Const.INVALID_HANDLE_VALUE) {
michael@0:          throw new File.Error("open", ctypes.winLastError, 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 "0" 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 0, this function raises
michael@0:       * an error holding ctypes.winLastError, otherwise it returns |result|.
michael@0:       * @param {string=} path The path of the file.
michael@0:       */
michael@0:      function throw_on_zero(operation, result, path) {
michael@0:        if (result == 0) {
michael@0:          throw new File.Error(operation, ctypes.winLastError, path);
michael@0:        }
michael@0:        return result;
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.winLastError, 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.winLastError, 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.winLastError, 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.winLastError, path);
michael@0:        }
michael@0:        return result;
michael@0:      }
michael@0: 
michael@0:      File.Win = exports.OS.Win.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: }