Merge pull request #1498 from inolen/lib_reorg

FS-related module reorganization

6 files changed, 1752 insertions, 1754 deletions

diff --git a/src/library.js b/src/library.js
index 6ce77268..fedb8760 100644
--- a/src/library.js
+++ b/src/library.js
@@ -18,1737 +18,12 @@
 // Memory allocated during startup, in postsets, should only be ALLOC_STATIC
 
 LibraryManager.library = {
-  // ==========================================================================
-  // File system base.
-  // ==========================================================================
-
   // keep this low in memory, because we flatten arrays with them in them
   stdin: 'allocate(1, "i32*", ALLOC_STATIC)',
   stdout: 'allocate(1, "i32*", ALLOC_STATIC)',
   stderr: 'allocate(1, "i32*", ALLOC_STATIC)',
   _impure_ptr: 'allocate(1, "i32*", ALLOC_STATIC)',
 
-  $FS__deps: ['$ERRNO_CODES', '$ERRNO_MESSAGES', '__setErrNo', '$VFS', '$PATH', '$TTY', '$MEMFS', 'stdin', 'stdout', 'stderr', 'fflush'],
-  $FS__postset: 'FS.staticInit();' +
-                '__ATINIT__.unshift({ func: function() { if (!Module["noFSInit"] && !FS.init.initialized) FS.init() } });' +
-                '__ATMAIN__.push({ func: function() { FS.ignorePermissions = false } });' +
-                '__ATEXIT__.push({ func: function() { FS.quit() } });' +
-                // export some names through closure
-                'Module["FS_createFolder"] = FS.createFolder;' +
-                'Module["FS_createPath"] = FS.createPath;' +
-                'Module["FS_createDataFile"] = FS.createDataFile;' +
-                'Module["FS_createPreloadedFile"] = FS.createPreloadedFile;' +
-                'Module["FS_createLazyFile"] = FS.createLazyFile;' +
-                'Module["FS_createLink"] = FS.createLink;' +
-                'Module["FS_createDevice"] = FS.createDevice;',
-  $FS: {
-    root: null,
-    nodes: [null],
-    devices: [null],
-    streams: [null],
-    nextInode: 1,
-    name_table: new Array(4096),
-    currentPath: '/',
-    initialized: false,
-    // Whether we are currently ignoring permissions. Useful when preparing the
-    // filesystem and creating files inside read-only folders.
-    // This is set to false when the runtime is initialized, allowing you
-    // to modify the filesystem freely before run() is called.
-    ignorePermissions: true,
-    
-    ErrnoError: function(errno) {
-      this.errno = errno;
-      for (var key in ERRNO_CODES) {
-        if (ERRNO_CODES[key] === errno) {
-          this.code = key;
-          break;
-        }
-      }
-      this.message = ERRNO_MESSAGES[errno];
-    },
-
-    handleFSError: function(e) {
-      if (!(e instanceof FS.ErrnoError)) throw e + ' : ' + new Error().stack;
-      return ___setErrNo(e.errno);
-    },
-
-    //
-    // nodes
-    //
-    hashName: function(parentid, name) {
-      var hash = 0;
-      for (var i = 0; i < name.length; i++) {
-        hash = ((hash << 5) - hash + name.charCodeAt(i)) | 0;
-      }
-      return (parentid + hash) % FS.name_table.length;
-    },
-    hashAddNode: function(node) {
-      var hash = FS.hashName(node.parent.id, node.name);
-      node.name_next = FS.name_table[hash];
-      FS.name_table[hash] = node;
-    },
-    hashRemoveNode: function(node) {
-      var hash = FS.hashName(node.parent.id, node.name);
-      if (FS.name_table[hash] === node) {
-        FS.name_table[hash] = node.name_next;
-      } else {
-        var current = FS.name_table[hash];
-        while (current) {
-          if (current.name_next === node) {
-            current.name_next = node.name_next;
-            break;
-          }
-          current = current.name_next;
-        }
-      }
-    },
-    lookupNode: function(parent, name) {
-      var err = FS.mayLookup(parent);
-      if (err) {
-        throw new FS.ErrnoError(err);
-      }
-      var hash = FS.hashName(parent.id, name);
-      for (var node = FS.name_table[hash]; node; node = node.name_next) {
-        if (node.parent.id === parent.id && node.name === name) {
-          return node;
-        }
-      }
-      // if we failed to find it in the cache, call into the VFS
-      return VFS.lookup(parent, name);
-    },
-    createNode: function(parent, name, mode, rdev) {
-      var node = {
-        id: FS.nextInode++,
-        name: name,
-        mode: mode,
-        node_ops: {},
-        stream_ops: {},
-        rdev: rdev,
-        parent: null,
-        mount: null
-      };
-      if (!parent) {
-        parent = node;  // root node sets parent to itself
-      }
-      node.parent = parent;
-      node.mount = parent.mount;
-      // compatibility
-      var readMode = {{{ cDefine('S_IRUGO') }}} | {{{ cDefine('S_IXUGO') }}};
-      var writeMode = {{{ cDefine('S_IWUGO') }}};
-      // NOTE we must use Object.defineProperties instead of individual calls to
-      // Object.defineProperty in order to make closure compiler happy
-      Object.defineProperties(node, {
-        read: {
-          get: function() { return (node.mode & readMode) === readMode; },
-          set: function(val) { val ? node.mode |= readMode : node.mode &= ~readMode; }
-        },
-        write: {
-          get: function() { return (node.mode & writeMode) === writeMode; },
-          set: function(val) { val ? node.mode |= writeMode : node.mode &= ~writeMode; }
-        },
-        isFolder: {
-          get: function() { return FS.isDir(node.mode); },
-        },
-        isDevice: {
-          get: function() { return FS.isChrdev(node.mode); },
-        },
-      });
-      FS.hashAddNode(node);
-      return node;
-    },
-    destroyNode: function(node) {
-      FS.hashRemoveNode(node);
-    },
-    isRoot: function(node) {
-      return node === node.parent;
-    },
-    isMountpoint: function(node) {
-      return node.mounted;
-    },
-    isFile: function(mode) {
-      return (mode & {{{ cDefine('S_IFMT') }}}) === {{{ cDefine('S_IFREG') }}};
-    },
-    isDir: function(mode) {
-      return (mode & {{{ cDefine('S_IFMT') }}}) === {{{ cDefine('S_IFDIR') }}};
-    },
-    isLink: function(mode) {
-      return (mode & {{{ cDefine('S_IFMT') }}}) === {{{ cDefine('S_IFLNK') }}};
-    },
-    isChrdev: function(mode) {
-      return (mode & {{{ cDefine('S_IFMT') }}}) === {{{ cDefine('S_IFCHR') }}};
-    },
-    isBlkdev: function(mode) {
-      return (mode & {{{ cDefine('S_IFMT') }}}) === {{{ cDefine('S_IFBLK') }}};
-    },
-    isFIFO: function(mode) {
-      return (mode & {{{ cDefine('S_IFMT') }}}) === {{{ cDefine('S_IFIFO') }}};
-    },
-
-    //
-    // paths
-    //
-    cwd: function() {
-      return FS.currentPath;
-    },
-    lookupPath: function(path, opts) {
-      path = PATH.resolve(FS.currentPath, path);
-      opts = opts || { recurse_count: 0 };
-
-      if (opts.recurse_count > 8) {  // max recursive lookup of 8
-        throw new FS.ErrnoError(ERRNO_CODES.ELOOP);
-      }
-
-      // split the path
-      var parts = PATH.normalizeArray(path.split('/').filter(function(p) {
-        return !!p;
-      }), false);
-
-      // start at the root
-      var current = FS.root;
-      var current_path = '/';
-
-      for (var i = 0; i < parts.length; i++) {
-        var islast = (i === parts.length-1);
-        if (islast && opts.parent) {
-          // stop resolving
-          break;
-        }
-
-        current = FS.lookupNode(current, parts[i]);
-        current_path = PATH.join(current_path, parts[i]);
-
-        // jump to the mount's root node if this is a mountpoint
-        if (FS.isMountpoint(current)) {
-          current = current.mount.root;
-        }
-
-        // follow symlinks
-        // by default, lookupPath will not follow a symlink if it is the final path component.
-        // setting opts.follow = true will override this behavior.
-        if (!islast || opts.follow) {
-          var count = 0;
-          while (FS.isLink(current.mode)) {
-            var link = VFS.readlink(current_path);
-            current_path = PATH.resolve(PATH.dirname(current_path), link);
-            
-            var lookup = FS.lookupPath(current_path, { recurse_count: opts.recurse_count });
-            current = lookup.node;
-
-            if (count++ > 40) {  // limit max consecutive symlinks to 40 (SYMLOOP_MAX).
-              throw new FS.ErrnoError(ERRNO_CODES.ELOOP);
-            }
-          }
-        }
-      }
-
-      return { path: current_path, node: current };
-    },
-    getPath: function(node) {
-      var path;
-      while (true) {
-        if (FS.isRoot(node)) {
-          return path ? PATH.join(node.mount.mountpoint, path) : node.mount.mountpoint;
-        }
-        path = path ? PATH.join(node.name, path) : node.name;
-        node = node.parent;
-      }
-    },
-
-    //
-    // permissions
-    //
-    flagModes: {
-      '"r"': {{{ cDefine('O_RDONLY') }}},
-      '"rs"': {{{ cDefine('O_RDONLY') }}} | {{{ cDefine('O_SYNC') }}},
-      '"r+"': {{{ cDefine('O_RDWR') }}},
-      '"w"': {{{ cDefine('O_TRUNC') }}} | {{{ cDefine('O_CREAT') }}} | {{{ cDefine('O_WRONLY') }}},
-      '"wx"': {{{ cDefine('O_TRUNC') }}} | {{{ cDefine('O_CREAT') }}} | {{{ cDefine('O_WRONLY') }}} | {{{ cDefine('O_EXCL') }}},
-      '"xw"': {{{ cDefine('O_TRUNC') }}} | {{{ cDefine('O_CREAT') }}} | {{{ cDefine('O_WRONLY') }}} | {{{ cDefine('O_EXCL') }}},
-      '"w+"': {{{ cDefine('O_TRUNC') }}} | {{{ cDefine('O_CREAT') }}} | {{{ cDefine('O_RDWR') }}},
-      '"wx+"': {{{ cDefine('O_TRUNC') }}} | {{{ cDefine('O_CREAT') }}} | {{{ cDefine('O_RDWR') }}} | {{{ cDefine('O_EXCL') }}},
-      '"xw+"': {{{ cDefine('O_TRUNC') }}} | {{{ cDefine('O_CREAT') }}} | {{{ cDefine('O_RDWR') }}} | {{{ cDefine('O_EXCL') }}},
-      '"a"': {{{ cDefine('O_APPEND') }}} | {{{ cDefine('O_CREAT') }}} | {{{ cDefine('O_WRONLY') }}},
-      '"ax"': {{{ cDefine('O_APPEND') }}} | {{{ cDefine('O_CREAT') }}} | {{{ cDefine('O_WRONLY') }}} | {{{ cDefine('O_EXCL') }}},
-      '"xa"': {{{ cDefine('O_APPEND') }}} | {{{ cDefine('O_CREAT') }}} | {{{ cDefine('O_WRONLY') }}} | {{{ cDefine('O_EXCL') }}},
-      '"a+"': {{{ cDefine('O_APPEND') }}} | {{{ cDefine('O_CREAT') }}} | {{{ cDefine('O_RDWR') }}},
-      '"ax+"': {{{ cDefine('O_APPEND') }}} | {{{ cDefine('O_CREAT') }}} | {{{ cDefine('O_RDWR') }}} | {{{ cDefine('O_EXCL') }}},
-      '"xa+"': {{{ cDefine('O_APPEND') }}} | {{{ cDefine('O_CREAT') }}} | {{{ cDefine('O_RDWR') }}} | {{{ cDefine('O_EXCL') }}}
-    },
-    // convert the 'r', 'r+', etc. to it's corresponding set of O_* flags
-    modeStringToFlags: function(str) {
-      var flags = FS.flagModes[str];
-      if (typeof flags === 'undefined') {
-        throw new Error('Unknown file open mode: ' + str);
-      }
-      return flags;
-    },
-    // convert O_* bitmask to a string for nodePermissions
-    flagsToPermissionString: function(flag) {
-      var accmode = flag & {{{ cDefine('O_ACCMODE') }}};
-      var perms = ['r', 'w', 'rw'][accmode];
-      if ((flag & {{{ cDefine('O_TRUNC') }}})) {
-        perms += 'w';
-      }
-      return perms;
-    },
-    nodePermissions: function(node, perms) {
-      if (FS.ignorePermissions) {
-        return 0;
-      }
-      // return 0 if any user, group or owner bits are set.
-      if (perms.indexOf('r') !== -1 && !(node.mode & {{{ cDefine('S_IRUGO') }}})) {
-        return ERRNO_CODES.EACCES;
-      } else if (perms.indexOf('w') !== -1 && !(node.mode & {{{ cDefine('S_IWUGO') }}})) {
-        return ERRNO_CODES.EACCES;
-      } else if (perms.indexOf('x') !== -1 && !(node.mode & {{{ cDefine('S_IXUGO') }}})) {
-        return ERRNO_CODES.EACCES;
-      }
-      return 0;
-    },
-    mayLookup: function(dir) {
-      return FS.nodePermissions(dir, 'x');
-    },
-    mayMknod: function(mode) {
-      switch (mode & {{{ cDefine('S_IFMT') }}}) {
-        case {{{ cDefine('S_IFREG') }}}:
-        case {{{ cDefine('S_IFCHR') }}}:
-        case {{{ cDefine('S_IFBLK') }}}:
-        case {{{ cDefine('S_IFIFO') }}}:
-        case {{{ cDefine('S_IFSOCK') }}}:
-          return 0;
-        default:
-          return ERRNO_CODES.EINVAL;
-      }
-    },
-    mayCreate: function(dir, name) {
-      try {
-        var node = FS.lookupNode(dir, name);
-        return ERRNO_CODES.EEXIST;
-      } catch (e) {
-      }
-      return FS.nodePermissions(dir, 'wx');
-    },
-    mayDelete: function(dir, name, isdir) {
-      var node;
-      try {
-        node = FS.lookupNode(dir, name);
-      } catch (e) {
-        return e.errno;
-      }
-      var err = FS.nodePermissions(dir, 'wx');
-      if (err) {
-        return err;
-      }
-      if (isdir) {
-        if (!FS.isDir(node.mode)) {
-          return ERRNO_CODES.ENOTDIR;
-        }
-        if (FS.isRoot(node) || FS.getPath(node) === FS.currentPath) {
-          return ERRNO_CODES.EBUSY;
-        }
-      } else {
-        if (FS.isDir(node.mode)) {
-          return ERRNO_CODES.EISDIR;
-        }
-      }
-      return 0;
-    },
-    mayOpen: function(node, flags) {
-      if (!node) {
-        return ERRNO_CODES.ENOENT;
-      }
-      if (FS.isLink(node.mode)) {
-        return ERRNO_CODES.ELOOP;
-      } else if (FS.isDir(node.mode)) {
-        if ((flags & {{{ cDefine('O_ACCMODE') }}}) !== {{{ cDefine('O_RDONLY')}}} ||  // opening for write
-            (flags & {{{ cDefine('O_TRUNC') }}})) {
-          return ERRNO_CODES.EISDIR;
-        }
-      }
-      return FS.nodePermissions(node, FS.flagsToPermissionString(flags));
-    },
-
-    //
-    // devices
-    //
-    // each character device consists of a device id + stream operations.
-    // when a character device node is created (e.g. /dev/stdin) it is
-    // assigned a device id that lets us map back to the actual device.
-    // by default, each character device stream (e.g. _stdin) uses chrdev_stream_ops.
-    // however, once opened, the stream's operations are overridden with
-    // the operations of the device its underlying node maps back to.
-    chrdev_stream_ops: {
-      open: function(stream) {
-        var device = FS.getDevice(stream.node.rdev);
-        // override node's stream ops with the device's
-        stream.stream_ops = device.stream_ops;
-        // forward the open call
-        if (stream.stream_ops.open) {
-          stream.stream_ops.open(stream);
-        }
-      },
-      llseek: function() {
-        throw new FS.ErrnoError(ERRNO_CODES.ESPIPE);
-      }
-    },
-    major: function(dev) {
-      return ((dev) >> 8);
-    },
-    minor: function(dev) {
-      return ((dev) & 0xff);
-    },
-    makedev: function(ma, mi) {
-      return ((ma) << 8 | (mi));
-    },
-    registerDevice: function(dev, ops) {
-      FS.devices[dev] = { stream_ops: ops };
-    },
-    getDevice: function(dev) {
-      return FS.devices[dev];
-    },
-
-    //
-    // streams
-    //
-    MAX_OPEN_FDS: 4096,
-    nextfd: function(fd_start, fd_end) {
-      fd_start = fd_start || 1;
-      fd_end = fd_end || FS.MAX_OPEN_FDS;
-      for (var fd = fd_start; fd <= fd_end; fd++) {
-        if (!FS.streams[fd]) {
-          return fd;
-        }
-      }
-      throw new FS.ErrnoError(ERRNO_CODES.EMFILE);
-    },
-    getStream: function(fd) {
-      return FS.streams[fd];
-    },
-    createStream: function(stream, fd_start, fd_end) {
-      var fd = FS.nextfd(fd_start, fd_end);
-      stream.fd = fd;
-      // compatibility
-      Object.defineProperties(stream, {
-        object: {
-          get: function() { return stream.node; },
-          set: function(val) { stream.node = val; }
-        },
-        isRead: {
-          get: function() { return (stream.flags & {{{ cDefine('O_ACCMODE') }}}) !== {{{ cDefine('O_WRONLY') }}}; }
-        },
-        isWrite: {
-          get: function() { return (stream.flags & {{{ cDefine('O_ACCMODE') }}}) !== {{{ cDefine('O_RDONLY') }}}; }
-        },
-        isAppend: {
-          get: function() { return (stream.flags & {{{ cDefine('O_APPEND') }}}); }
-        }
-      });
-      FS.streams[fd] = stream;
-      return stream;
-    },
-    closeStream: function(fd) {
-      FS.streams[fd] = null;
-    },
-
-    //
-    // general
-    //
-    createDefaultDirectories: function() {
-      VFS.mkdir('/tmp', 0777);
-    },
-    createDefaultDevices: function() {
-      // create /dev
-      VFS.mkdir('/dev', 0777);
-      // setup /dev/null
-      FS.registerDevice(FS.makedev(1, 3), {
-        read: function() { return 0; },
-        write: function() { return 0; }
-      });
-      VFS.mkdev('/dev/null', 0666, FS.makedev(1, 3));
-      // setup /dev/tty and /dev/tty1
-      // stderr needs to print output using Module['printErr']
-      // so we register a second tty just for it.
-      TTY.register(FS.makedev(5, 0), TTY.default_tty_ops);
-      TTY.register(FS.makedev(6, 0), TTY.default_tty1_ops);
-      VFS.mkdev('/dev/tty', 0666, FS.makedev(5, 0));
-      VFS.mkdev('/dev/tty1', 0666, FS.makedev(6, 0));
-      // we're not going to emulate the actual shm device,
-      // just create the tmp dirs that reside in it commonly
-      VFS.mkdir('/dev/shm', 0777);
-      VFS.mkdir('/dev/shm/tmp', 0777);
-    },
-    createStandardStreams: function() {
-      // TODO deprecate the old functionality of a single
-      // input / output callback and that utilizes FS.createDevice
-      // and instead require a unique set of stream ops
-
-      // by default, we symlink the standard streams to the
-      // default tty devices. however, if the standard streams
-      // have been overwritten we create a unique device for
-      // them instead.
-      if (Module['stdin']) {
-        FS.createDevice('/dev', 'stdin', Module['stdin']);
-      } else {
-        VFS.symlink('/dev/tty', '/dev/stdin');
-      }
-      if (Module['stdout']) {
-        FS.createDevice('/dev', 'stdout', null, Module['stdout']);
-      } else {
-        VFS.symlink('/dev/tty', '/dev/stdout');
-      }
-      if (Module['stderr']) {
-        FS.createDevice('/dev', 'stderr', null, Module['stderr']);
-      } else {
-        VFS.symlink('/dev/tty1', '/dev/stderr');
-      }
-
-      // open default streams for the stdin, stdout and stderr devices
-      var stdin = VFS.open('/dev/stdin', 'r');
-      {{{ makeSetValue(makeGlobalUse('_stdin'), 0, 'stdin.fd', 'void*') }}};
-      assert(stdin.fd === 1, 'invalid handle for stdin (' + stdin.fd + ')');
-
-      var stdout = VFS.open('/dev/stdout', 'w');
-      {{{ makeSetValue(makeGlobalUse('_stdout'), 0, 'stdout.fd', 'void*') }}};
-      assert(stdout.fd === 2, 'invalid handle for stdout (' + stdout.fd + ')');
-
-      var stderr = VFS.open('/dev/stderr', 'w');
-      {{{ makeSetValue(makeGlobalUse('_stderr'), 0, 'stderr.fd', 'void*') }}};
-      assert(stderr.fd === 3, 'invalid handle for stderr (' + stderr.fd + ')');
-    },
-    staticInit: function() {
-      FS.root = FS.createNode(null, '/', {{{ cDefine('S_IFDIR') }}} | 0777, 0);
-      VFS.mount(MEMFS, {}, '/');
-
-      FS.createDefaultDirectories();
-      FS.createDefaultDevices();
-    },
-    init: function(input, output, error) {
-      assert(!FS.init.initialized, 'FS.init was previously called. If you want to initialize later with custom parameters, remove any earlier calls (note that one is automatically added to the generated code)');
-      FS.init.initialized = true;
-
-      // Allow Module.stdin etc. to provide defaults, if none explicitly passed to us here
-      Module['stdin'] = input || Module['stdin'];
-      Module['stdout'] = output || Module['stdout'];
-      Module['stderr'] = error || Module['stderr'];
-
-      FS.createStandardStreams();
-    },
-    quit: function() {
-      FS.init.initialized = false;
-      for (var i = 0; i < FS.streams.length; i++) {
-        var stream = FS.streams[i];
-        if (!stream) {
-          continue;
-        }
-        VFS.close(stream);
-      }
-    },
-
-    //
-    // compatibility
-    //
-    getMode: function(canRead, canWrite) {
-      var mode = 0;
-      if (canRead) mode |= {{{ cDefine('S_IRUGO') }}} | {{{ cDefine('S_IXUGO') }}};
-      if (canWrite) mode |= {{{ cDefine('S_IWUGO') }}};
-      return mode;
-    },
-    joinPath: function(parts, forceRelative) {
-      var path = PATH.join.apply(null, parts);
-      if (forceRelative && path[0] == '/') path = path.substr(1);
-      return path;
-    },
-    absolutePath: function(relative, base) {
-      return PATH.resolve(base, relative);
-    },
-    standardizePath: function(path) {
-      return PATH.normalize(path);
-    },
-    findObject: function(path, dontResolveLastLink) {
-      var ret = FS.analyzePath(path, dontResolveLastLink);
-      if (ret.exists) {
-        return ret.object;
-      } else {
-        ___setErrNo(ret.error);
-        return null;
-      }
-    },
-    analyzePath: function(path, dontResolveLastLink) {
-      // operate from within the context of the symlink's target
-      try {
-        var lookup = FS.lookupPath(path, { follow: !dontResolveLastLink });
-        path = lookup.path;
-      } catch (e) {
-      }
-      var ret = {
-        isRoot: false, exists: false, error: 0, name: null, path: null, object: null,
-        parentExists: false, parentPath: null, parentObject: null
-      };
-      try {
-        var lookup = FS.lookupPath(path, { parent: true });
-        ret.parentExists = true;
-        ret.parentPath = lookup.path;
-        ret.parentObject = lookup.node;
-        ret.name = PATH.basename(path);
-        lookup = FS.lookupPath(path, { follow: !dontResolveLastLink });
-        ret.exists = true;
-        ret.path = lookup.path;
-        ret.object = lookup.node;
-        ret.name = lookup.node.name;
-        ret.isRoot = lookup.path === '/';
-      } catch (e) {
-        ret.error = e.errno;
-      };
-      return ret;
-    },
-    createFolder: function(parent, name, canRead, canWrite) {
-      var path = PATH.join(typeof parent === 'string' ? parent : FS.getPath(parent), name);
-      var mode = FS.getMode(canRead, canWrite);
-      return VFS.mkdir(path, mode);
-    },
-    createPath: function(parent, path, canRead, canWrite) {
-      parent = typeof parent === 'string' ? parent : FS.getPath(parent);
-      var parts = path.split('/').reverse();
-      while (parts.length) {
-        var part = parts.pop();
-        if (!part) continue;
-        var current = PATH.join(parent, part);
-        try {
-          VFS.mkdir(current, 0777);
-        } catch (e) {
-          // ignore EEXIST
-        }
-        parent = current;
-      }
-      return current;
-    },
-    createFile: function(parent, name, properties, canRead, canWrite) {
-      var path = PATH.join(typeof parent === 'string' ? parent : FS.getPath(parent), name);
-      var mode = FS.getMode(canRead, canWrite);
-      return VFS.create(path, mode);
-    },
-    createDataFile: function(parent, name, data, canRead, canWrite) {
-      var path = PATH.join(typeof parent === 'string' ? parent : FS.getPath(parent), name);
-      var mode = FS.getMode(canRead, canWrite);
-      var node = VFS.create(path, mode);
-      if (data) {
-        if (typeof data === 'string') {
-          var arr = new Array(data.length);
-          for (var i = 0, len = data.length; i < len; ++i) arr[i] = data.charCodeAt(i);
-          data = arr;
-        }
-        // make sure we can write to the file
-        VFS.chmod(path, mode | {{{ cDefine('S_IWUGO') }}});
-        var stream = VFS.open(path, 'w');
-        VFS.write(stream, data, 0, data.length, 0);
-        VFS.close(stream);
-        VFS.chmod(path, mode);
-      }
-      return node;
-    },
-    createDevice: function(parent, name, input, output) {
-      var path = PATH.join(typeof parent === 'string' ? parent : FS.getPath(parent), name);
-      var mode = input && output ? 0777 : (input ? 0333 : 0555);
-      if (!FS.createDevice.major) FS.createDevice.major = 64;
-      var dev = FS.makedev(FS.createDevice.major++, 0);
-      // Create a fake device that a set of stream ops to emulate
-      // the old behavior.
-      FS.registerDevice(dev, {
-        open: function(stream) {
-          stream.seekable = false;
-        },
-        close: function(stream) {
-          // flush any pending line data
-          if (output && output.buffer && output.buffer.length) {
-            output({{{ charCode('\n') }}});
-          }
-        },
-        read: function(stream, buffer, offset, length, pos /* ignored */) {
-          var bytesRead = 0;
-          for (var i = 0; i < length; i++) {
-            var result;
-            try {
-              result = input();
-            } catch (e) {
-              throw new FS.ErrnoError(ERRNO_CODES.EIO);
-            }
-            if (result === undefined && bytesRead === 0) {
-              throw new FS.ErrnoError(ERRNO_CODES.EAGAIN);
-            }
-            if (result === null || result === undefined) break;
-            bytesRead++;
-            buffer[offset+i] = result;
-          }
-          if (bytesRead) {
-            stream.node.timestamp = Date.now();
-          }
-          return bytesRead;
-        },
-        write: function(stream, buffer, offset, length, pos) {
-          for (var i = 0; i < length; i++) {
-            try {
-              output(buffer[offset+i]);
-            } catch (e) {
-              throw new FS.ErrnoError(ERRNO_CODES.EIO);
-            }
-          }
-          if (length) {
-            stream.node.timestamp = Date.now();
-          }
-          return i;
-        }
-      });
-      return VFS.mkdev(path, mode, dev);
-    },
-    createLink: function(parent, name, target, canRead, canWrite) {
-      var path = PATH.join(typeof parent === 'string' ? parent : FS.getPath(parent), name);
-      return VFS.symlink(target, path);
-    },
-    // Makes sure a file's contents are loaded. Returns whether the file has
-    // been loaded successfully. No-op for files that have been loaded already.
-    forceLoadFile: function(obj) {
-      if (obj.isDevice || obj.isFolder || obj.link || obj.contents) return true;
-      var success = true;
-      if (typeof XMLHttpRequest !== 'undefined') {
-        throw new Error("Lazy loading should have been performed (contents set) in createLazyFile, but it was not. Lazy loading only works in web workers. Use --embed-file or --preload-file in emcc on the main thread.");
-      } else if (Module['read']) {
-        // Command-line.
-        try {
-          // WARNING: Can't read binary files in V8's d8 or tracemonkey's js, as
-          //          read() will try to parse UTF8.
-          obj.contents = intArrayFromString(Module['read'](obj.url), true);
-        } catch (e) {
-          success = false;
-        }
-      } else {
-        throw new Error('Cannot load without read() or XMLHttpRequest.');
-      }
-      if (!success) ___setErrNo(ERRNO_CODES.EIO);
-      return success;
-    },
-    // Creates a file record for lazy-loading from a URL. XXX This requires a synchronous
-    // XHR, which is not possible in browsers except in a web worker! Use preloading,
-    // either --preload-file in emcc or FS.createPreloadedFile
-    createLazyFile: function(parent, name, url, canRead, canWrite) {
-      if (typeof XMLHttpRequest !== 'undefined') {
-        if (!ENVIRONMENT_IS_WORKER) throw 'Cannot do synchronous binary XHRs outside webworkers in modern browsers. Use --embed-file or --preload-file in emcc';
-        // Lazy chunked Uint8Array (implements get and length from Uint8Array). Actual getting is abstracted away for eventual reuse.
-        var LazyUint8Array = function() {
-          this.lengthKnown = false;
-          this.chunks = []; // Loaded chunks. Index is the chunk number
-        }
-        LazyUint8Array.prototype.get = function(idx) {
-          if (idx > this.length-1 || idx < 0) {
-            return undefined;
-          }
-          var chunkOffset = idx % this.chunkSize;
-          var chunkNum = Math.floor(idx / this.chunkSize);
-          return this.getter(chunkNum)[chunkOffset];
-        }
-        LazyUint8Array.prototype.setDataGetter = function(getter) {
-          this.getter = getter;
-        }
-        LazyUint8Array.prototype.cacheLength = function() {
-            // Find length
-            var xhr = new XMLHttpRequest();
-            xhr.open('HEAD', url, false);
-            xhr.send(null);
-            if (!(xhr.status >= 200 && xhr.status < 300 || xhr.status === 304)) throw new Error("Couldn't load " + url + ". Status: " + xhr.status);
-            var datalength = Number(xhr.getResponseHeader("Content-length"));
-            var header;
-            var hasByteServing = (header = xhr.getResponseHeader("Accept-Ranges")) && header === "bytes";
-#if SMALL_XHR_CHUNKS
-            var chunkSize = 1024; // Chunk size in bytes
-#else
-            var chunkSize = 1024*1024; // Chunk size in bytes
-#endif
-
-            if (!hasByteServing) chunkSize = datalength;
-
-            // Function to get a range from the remote URL.
-            var doXHR = (function(from, to) {
-              if (from > to) throw new Error("invalid range (" + from + ", " + to + ") or no bytes requested!");
-              if (to > datalength-1) throw new Error("only " + datalength + " bytes available! programmer error!");
-
-              // TODO: Use mozResponseArrayBuffer, responseStream, etc. if available.
-              var xhr = new XMLHttpRequest();
-              xhr.open('GET', url, false);
-              if (datalength !== chunkSize) xhr.setRequestHeader("Range", "bytes=" + from + "-" + to);
-
-              // Some hints to the browser that we want binary data.
-              if (typeof Uint8Array != 'undefined') xhr.responseType = 'arraybuffer';
-              if (xhr.overrideMimeType) {
-                xhr.overrideMimeType('text/plain; charset=x-user-defined');
-              }
-
-              xhr.send(null);
-              if (!(xhr.status >= 200 && xhr.status < 300 || xhr.status === 304)) throw new Error("Couldn't load " + url + ". Status: " + xhr.status);
-              if (xhr.response !== undefined) {
-                return new Uint8Array(xhr.response || []);
-              } else {
-                return intArrayFromString(xhr.responseText || '', true);
-              }
-            });
-            var lazyArray = this;
-            lazyArray.setDataGetter(function(chunkNum) {
-              var start = chunkNum * chunkSize;
-              var end = (chunkNum+1) * chunkSize - 1; // including this byte
-              end = Math.min(end, datalength-1); // if datalength-1 is selected, this is the last block
-              if (typeof(lazyArray.chunks[chunkNum]) === "undefined") {
-                lazyArray.chunks[chunkNum] = doXHR(start, end);
-              }
-              if (typeof(lazyArray.chunks[chunkNum]) === "undefined") throw new Error("doXHR failed!");
-              return lazyArray.chunks[chunkNum];
-            });
-
-            this._length = datalength;
-            this._chunkSize = chunkSize;
-            this.lengthKnown = true;
-        }
-
-        var lazyArray = new LazyUint8Array();
-        Object.defineProperty(lazyArray, "length", {
-            get: function() {
-                if(!this.lengthKnown) {
-                    this.cacheLength();
-                }
-                return this._length;
-            }
-        });
-        Object.defineProperty(lazyArray, "chunkSize", {
-            get: function() {
-                if(!this.lengthKnown) {
-                    this.cacheLength();
-                }
-                return this._chunkSize;
-            }
-        });
-
-        var properties = { isDevice: false, contents: lazyArray };
-      } else {
-        var properties = { isDevice: false, url: url };
-      }
-
-      var node = FS.createFile(parent, name, properties, canRead, canWrite);
-      // This is a total hack, but I want to get this lazy file code out of the
-      // core of MEMFS. If we want to keep this lazy file concept I feel it should
-      // be its own thin LAZYFS proxying calls to MEMFS.
-      if (properties.contents) {
-        node.contents = properties.contents;
-      } else if (properties.url) {
-        node.contents = null;
-        node.url = properties.url;
-      }
-      // override each stream op with one that tries to force load the lazy file first
-      var stream_ops = {};
-      var keys = Object.keys(node.stream_ops);
-      keys.forEach(function(key) {
-        var fn = node.stream_ops[key];
-        stream_ops[key] = function() {
-          if (!FS.forceLoadFile(node)) {
-            throw new FS.ErrnoError(ERRNO_CODES.EIO);
-          }
-          return fn.apply(null, arguments);
-        };
-      });
-      // use a custom read function
-      stream_ops.read = function(stream, buffer, offset, length, position) {
-        var contents = stream.node.contents;
-        var size = Math.min(contents.length - position, length);
-        if (contents.slice) { // normal array
-          for (var i = 0; i < size; i++) {
-            buffer[offset + i] = contents[position + i];
-          }
-        } else {
-          for (var i = 0; i < size; i++) { // LazyUint8Array from sync binary XHR
-            buffer[offset + i] = contents.get(position + i);
-          }
-        }
-        return size;
-      };
-      node.stream_ops = stream_ops;
-      return node;
-    },
-    // Preloads a file asynchronously. You can call this before run, for example in
-    // preRun. run will be delayed until this file arrives and is set up.
-    // If you call it after run(), you may want to pause the main loop until it
-    // completes, if so, you can use the onload parameter to be notified when
-    // that happens.
-    // In addition to normally creating the file, we also asynchronously preload
-    // the browser-friendly versions of it: For an image, we preload an Image
-    // element and for an audio, and Audio. These are necessary for SDL_Image
-    // and _Mixer to find the files in preloadedImages/Audios.
-    // You can also call this with a typed array instead of a url. It will then
-    // do preloading for the Image/Audio part, as if the typed array were the
-    // result of an XHR that you did manually.
-    createPreloadedFile: function(parent, name, url, canRead, canWrite, onload, onerror, dontCreateFile) {
-      Browser.init();
-      // TODO we should allow people to just pass in a complete filename instead
-      // of parent and name being that we just join them anyways
-      var fullname = PATH.resolve(PATH.join(parent, name));
-      function processData(byteArray) {
-        function finish(byteArray) {
-          if (!dontCreateFile) {
-            FS.createDataFile(parent, name, byteArray, canRead, canWrite);
-          }
-          if (onload) onload();
-          removeRunDependency('cp ' + fullname);
-        }
-        var handled = false;
-        Module['preloadPlugins'].forEach(function(plugin) {
-          if (handled) return;
-          if (plugin['canHandle'](fullname)) {
-            plugin['handle'](byteArray, fullname, finish, function() {
-              if (onerror) onerror();
-              removeRunDependency('cp ' + fullname);
-            });
-            handled = true;
-          }
-        });
-        if (!handled) finish(byteArray);
-      }
-      addRunDependency('cp ' + fullname);
-      if (typeof url == 'string') {
-        Browser.asyncLoad(url, function(byteArray) {
-          processData(byteArray);
-        }, onerror);
-      } else {
-        processData(url);
-      }
-    }
-  },
-  
-  $VFS__deps: ['$FS'],
-  $VFS: {
-    mount: function(type, opts, mountpoint) {
-      var mount = {
-        type: type,
-        opts: opts,
-        mountpoint: mountpoint,
-        root: null
-      };
-      var lookup;
-      if (mountpoint) {
-        lookup = FS.lookupPath(mountpoint, { follow: false });
-      }
-      // create a root node for the fs
-      var root = type.mount(mount);
-      root.mount = mount;
-      mount.root = root;
-      // assign the mount info to the mountpoint's node
-      if (lookup) {
-        lookup.node.mount = mount;
-        lookup.node.mounted = true;
-        // compati