macfuse: another tahoe fuse implementation

This is the result of various experimentation done into using python-fuse
to provide access to tahoe on the mac.  It's rough in quite a few places,
and is really the result of investigation more than a thorough
implemenation of the fuse api.

upon launch, it looks for the users root_dir by opening ~/.tahoe/node.url
and ~/.tahoe/private/root_dir.cap it then proceeds to cache the directory
structure found by walking the users tahoe drive (safely in the face of
directory loops) into memory and then mounts that filesystem.

when a file is read, it calls the tahoe node to first download the file
into a cache directory (~/.tahoe/_cache) and then serves up the file
from there.

when a file is written, a temporary file is allocated within the tmp dir
of the cache, and upon close() (specifically upon release()) the file is
uploaded to the tahoe node, and the new directory entry written.

note that while the durectory structure is cached into memory only when
the filesystem is mounted, that it is 'write through' i.e. changes made
via fuse are reflected into the underlying tahoe fs, even though changes
made to the tahoe fs otherwise show up only upon restart.

in addition to opening files for read and write, the mkdir() and rename()
calls are supported.  most other file system operations are not yet
supported.  notably stat() metadata is not currently tracked by tahoe,
and is variably reported by this fs depending on write cache files.


also note that this version does not fully support Finder.  access through
normal unix commands such as cat, cp, mv, ls etc works fine, and read 
access to file from within finder (including preview images and double-
click to open) work ok.  but copies to the tahoe drive from within finder
may or may not succeed, but will always report an error. This is still
under investigation.

also note that this does not include any build integration.  the included
_fusemodule.so was built on mac os 10.4 against macfuse 1.3.0, and is
known to not work against 10.5-1.3.1  it's possible it may also contain
dependencies upon parts of macports used to build the python that it was
built against. this will be cleaned up later.

usage:
    python tahoefuse.py /Path/to/choice/of/mountpoint
or optionally
    python tahoefuse.py -ovolicon=/Path/to/icon.icns /Path/to/mountpoint

upon startup, tahoefuse will walk the tahoe directory, then print a
summary of files and folders found, and then daemonise itself. to exit,
either eject the 'drive' (note: 10.5 doesn't show it as a drive, since
it considers fuse to be a connected server instead) or unmount it via
umount /Path/to/mountpoint etc.

mac/macfuse/fuse.py

@@ -0,0 +1,997 @@
+#
+#    Copyright (C) 2001  Jeff Epler  <jepler@unpythonic.dhs.org>
+#    Copyright (C) 2006  Csaba Henk  <csaba.henk@creo.hu>
+#
+#    This program can be distributed under the terms of the GNU LGPL.
+#    See the file COPYING.
+#
+
+
+# suppress version mismatch warnings
+try:
+    import warnings
+    warnings.filterwarnings('ignore',
+                            'Python C API version mismatch',
+                            RuntimeWarning,
+                            )
+except:
+    pass
+
+from string import join
+import sys
+from errno import *
+from os import environ
+import re
+from fuseparts import __version__
+from fuseparts._fuse import main, FuseGetContext, FuseInvalidate
+from fuseparts._fuse import FuseError, FuseAPIVersion
+from fuseparts.subbedopts import SubOptsHive, SubbedOptFormatter
+from fuseparts.subbedopts import SubbedOptIndentedFormatter, SubbedOptParse
+from fuseparts.subbedopts import SUPPRESS_HELP, OptParseError
+from fuseparts.setcompatwrap import set
+
+
+##########
+###
+###  API specification API.
+###
+##########
+
+# The actual API version of this module
+FUSE_PYTHON_API_VERSION = (0, 2)
+
+def __getenv__(var, pattern = '.', trans = lambda x: x):
+    """
+    Fetch enviroment variable and optionally transform it. Return `None` if
+    variable is unset. Bail out if value of variable doesn't match (optional)
+    regex pattern.
+    """
+
+    if var not in environ:
+        return None
+    val = environ[var]
+    rpat = pattern
+    if not isinstance(rpat, type(re.compile(''))):
+        rpat = re.compile(rpat)
+    if not rpat.search(val):
+        raise RuntimeError("env var %s doesn't match required pattern %s" % \
+                           (var, `pattern`))
+    return trans(val)
+
+def get_fuse_python_api():
+    if fuse_python_api:
+        return fuse_python_api
+    elif compat_0_1:
+        # deprecated way of API specification
+        return (0,1)
+
+def get_compat_0_1():
+    return get_fuse_python_api() == (0, 1)
+
+# API version to be used
+fuse_python_api = __getenv__('FUSE_PYTHON_API', '^[\d.]+$',
+                              lambda x: tuple([int(i) for i in x.split('.')]))
+
+# deprecated way of API specification
+compat_0_1 = __getenv__('FUSE_PYTHON_COMPAT', '^(0.1|ALL)$', lambda x: True)
+
+fuse_python_api = get_fuse_python_api()
+
+##########
+###
+###  Parsing for FUSE.
+###
+##########
+
+
+
+class FuseArgs(SubOptsHive):
+    """
+    Class representing a FUSE command line.
+    """
+
+    fuse_modifiers = {'showhelp': '-ho',
+                      'showversion': '-V',
+                      'foreground': '-f'}
+
+    def __init__(self):
+
+        SubOptsHive.__init__(self)
+
+        self.modifiers = {}
+        self.mountpoint = None
+
+        for m in self.fuse_modifiers:
+            self.modifiers[m] = False
+
+    def __str__(self):
+        return '\n'.join(['< on ' + str(self.mountpoint) + ':',
+                          '  ' + str(self.modifiers), '  -o ']) + \
+               ',\n     '.join(self._str_core()) + \
+               ' >'
+
+    def getmod(self, mod):
+        return self.modifiers[mod]
+
+    def setmod(self, mod):
+        self.modifiers[mod] = True
+
+    def unsetmod(self, mod):
+        self.modifiers[mod] = False
+
+    def mount_expected(self):
+        if self.getmod('showhelp'):
+            return False
+        if self.getmod('showversion'):
+            return False
+        return True
+
+    def assemble(self):
+        """Mangle self into an argument array"""
+
+        self.canonify()
+        args = [sys.argv and sys.argv[0] or "python"]
+        if self.mountpoint:
+            args.append(self.mountpoint)
+        for m, v in self.modifiers.iteritems():
+            if v:
+                args.append(self.fuse_modifiers[m])
+
+        opta = []
+        for o, v in self.optdict.iteritems():
+                opta.append(o + '=' + v)
+        opta.extend(self.optlist)
+
+        if opta:
+            args.append("-o" + ",".join(opta))
+
+        return args
+
+    def filter(self, other=None):
+        """
+        Same as for SubOptsHive, with the following difference:
+        if other is not specified, `Fuse.fuseoptref()` is run and its result
+        will be used.
+        """
+
+        if not other:
+            other = Fuse.fuseoptref()
+
+        return SubOptsHive.filter(self, other)
+
+
+
+class FuseFormatter(SubbedOptIndentedFormatter):
+
+    def __init__(self, **kw):
+        if not 'indent_increment' in kw:
+            kw['indent_increment'] = 4
+        SubbedOptIndentedFormatter.__init__(self, **kw)
+
+    def store_option_strings(self, parser):
+        SubbedOptIndentedFormatter.store_option_strings(self, parser)
+        # 27 is how the lib stock help appears
+        self.help_position = max(self.help_position, 27)
+        self.help_width = self.width - self.help_position
+
+
+class FuseOptParse(SubbedOptParse):
+    """
+    This class alters / enhances `SubbedOptParse` so that it's
+    suitable for usage with FUSE.
+
+    - When adding options, you can use the `mountopt` pseudo-attribute which
+      is equivalent with adding a subopt for option ``-o``
+      (it doesn't require an option argument).
+
+    - FUSE compatible help and version printing.
+
+    - Error and exit callbacks are relaxed. In case of FUSE, the command
+      line is to be treated as a DSL [#]_. You don't wanna this module to
+      force an exit on you just because you hit a DSL syntax error.
+
+    - Built-in support for conventional FUSE options (``-d``, ``-f`, ``-s``).
+      The way of this can be tuned by keyword arguments, see below.
+
+    .. [#] http://en.wikipedia.org/wiki/Domain-specific_programming_language
+
+    Keyword arguments for initialization
+    ------------------------------------
+
+    standard_mods
+      Boolean [default is `True`].
+      Enables support for the usual interpretation of the ``-d``, ``-f``
+      options.
+
+    fetch_mp
+      Boolean [default is `True`].
+      If it's True, then the last (non-option) argument
+      (if there is such a thing) will be used as the FUSE mountpoint.
+
+    dash_s_do
+      String: ``whine``, ``undef``, or ``setsingle`` [default is ``whine``].
+      The ``-s`` option -- traditionally for asking for single-threadedness --
+      is an oddball: single/multi threadedness of a fuse-py fs doesn't depend
+      on the FUSE command line, we have direct control over it.
+
+      Therefore we have two conflicting principles:
+
+      - *Orthogonality*: option parsing shouldn't affect the backing `Fuse`
+        instance directly, only via its `fuse_args` attribute.
+
+      - *POLS*: behave like other FUSE based fs-es do. The stock FUSE help
+        makes mention of ``-s`` as a single-threadedness setter.
+
+      So, if we follow POLS and implement a conventional ``-s`` option, then
+      we have to go beyond the `fuse_args` attribute and set the respective
+      Fuse attribute directly, hence violating orthogonality.
+
+      We let the fs authors make their choice: ``dash_s_do=undef`` leaves this
+      option unhandled, and the fs author can add a handler as she desires.
+      ``dash_s_do=setsingle`` enables the traditional behaviour.
+
+      Using ``dash_s_do=setsingle`` is not problematic at all, but we want fs
+      authors be aware of the particularity of ``-s``, therefore the default is
+      the ``dash_s_do=whine`` setting which raises an exception for ``-s`` and
+      suggests the user to read this documentation.
+
+    dash_o_handler
+      Argument should be a SubbedOpt instance (created with
+      ``action="store_hive"`` if you want it to be useful).
+      This lets you customize the handler of the ``-o`` option. For example,
+      you can alter or suppress the generic ``-o`` entry in help output.
+    """
+
+    def __init__(self, *args, **kw):
+
+        self.mountopts = []
+
+        self.fuse_args = \
+            'fuse_args' in kw and kw.pop('fuse_args') or FuseArgs()
+        dsd = 'dash_s_do' in kw and kw.pop('dash_s_do') or 'whine'
+        if 'fetch_mp' in kw:
+            self.fetch_mp = bool(kw.pop('fetch_mp'))
+        else:
+            self.fetch_mp = True
+        if 'standard_mods' in kw:
+            smods = bool(kw.pop('standard_mods'))
+        else:
+            smods = True
+        if 'fuse' in kw:
+            self.fuse = kw.pop('fuse')
+        if not 'formatter' in kw:
+            kw['formatter'] = FuseFormatter()
+        doh = 'dash_o_handler' in kw and kw.pop('dash_o_handler')
+
+        SubbedOptParse.__init__(self, *args, **kw)
+
+        if doh:
+            self.add_option(doh)
+        else:
+            self.add_option('-o', action='store_hive',
+                            subopts_hive=self.fuse_args, help="mount options",
+                            metavar="opt,[opt...]")
+
+        if smods:
+            self.add_option('-f', action='callback',
+                            callback=lambda *a: self.fuse_args.setmod('foreground'),
+                            help=SUPPRESS_HELP)
+            self.add_option('-d', action='callback',
+                            callback=lambda *a: self.fuse_args.add('debug'),
+                            help=SUPPRESS_HELP)
+
+        if dsd == 'whine':
+            def dsdcb(option, opt_str, value, parser):
+                raise RuntimeError, """
+
+! If you want the "-s" option to work, pass
+!
+!   dash_s_do='setsingle'
+!
+! to the Fuse constructor. See docstring of the FuseOptParse class for an
+! explanation why is it not set by default.
+"""
+
+        elif dsd == 'setsingle':
+            def dsdcb(option, opt_str, value, parser):
+                self.fuse.multithreaded = False
+
+        elif dsd == 'undef':
+            dsdcb = None
+        else:
+            raise ArgumentError, "key `dash_s_do': uninterpreted value " + str(dsd)
+
+        if dsdcb:
+            self.add_option('-s', action='callback', callback=dsdcb,
+                            help=SUPPRESS_HELP)
+
+
+    def exit(self, status=0, msg=None):
+        if msg:
+            sys.stderr.write(msg)
+
+    def error(self, msg):
+        SubbedOptParse.error(self, msg)
+        raise OptParseError, msg
+
+    def print_help(self, file=sys.stderr):
+        SubbedOptParse.print_help(self, file)
+        print >> file
+        self.fuse_args.setmod('showhelp')
+
+    def print_version(self, file=sys.stderr):
+        SubbedOptParse.print_version(self, file)
+        self.fuse_args.setmod('showversion')
+
+    def parse_args(self, args=None, values=None):
+        o, a = SubbedOptParse.parse_args(self, args, values)
+        if a and self.fetch_mp:
+            self.fuse_args.mountpoint = a.pop()
+        return o, a
+
+    def add_option(self, *opts, **attrs):
+        if 'mountopt' in attrs:
+            if opts or 'subopt' in attrs:
+                raise OptParseError(
+                  "having options or specifying the `subopt' attribute conflicts with `mountopt' attribute")
+            opts = ('-o',)
+            attrs['subopt'] = attrs.pop('mountopt')
+            if not 'dest' in attrs:
+                attrs['dest'] = attrs['subopt']
+
+        SubbedOptParse.add_option(self, *opts, **attrs)
+
+
+
+##########
+###
+###  The FUSE interface.
+###
+##########
+
+
+
+class ErrnoWrapper(object):
+
+    def __init__(self, func):
+        self.func = func
+
+    def __call__(self, *args, **kw):
+        try:
+            return apply(self.func, args, kw)
+        except (IOError, OSError), detail:
+            # Sometimes this is an int, sometimes an instance...
+            if hasattr(detail, "errno"): detail = detail.errno
+            return -detail
+
+
+########### Custom objects for transmitting system structures to FUSE
+
+class FuseStruct(object):
+
+    def __init__(self, **kw):
+        for k in kw:
+             setattr(self, k, kw[k])
+
+
+class Stat(FuseStruct):
+    """
+    Auxiliary class which can be filled up stat attributes.
+    The attributes are undefined by default.
+    """
+
+    def __init__(self, **kw):
+        self.st_mode  = None
+        self.st_ino   = 0
+        self.st_dev   = 0
+        self.st_nlink = None
+        self.st_uid   = 0
+        self.st_gid   = 0
+        self.st_size  = 0
+        self.st_atime = 0
+        self.st_mtime = 0
+        self.st_ctime = 0
+
+        FuseStruct.__init__(self, **kw)
+
+
+class StatVfs(FuseStruct):
+    """
+    Auxiliary class which can be filled up statvfs attributes.
+    The attributes are 0 by default.
+    """
+
+    def __init__(self, **kw):
+
+        self.f_bsize   = 0
+        self.f_frsize  = 0
+        self.f_blocks  = 0
+        self.f_bfree   = 0
+        self.f_bavail  = 0
+        self.f_files   = 0
+        self.f_ffree   = 0
+        self.f_favail  = 0
+        self.f_flag    = 0
+        self.f_namemax = 0
+
+        FuseStruct.__init__(self, **kw)
+
+
+class Direntry(FuseStruct):
+    """
+    Auxiliary class for carrying directory entry data.
+    Initialized with `name`. Further attributes (each
+    set to 0 as default):
+
+    offset
+        An integer (or long) parameter, used as a bookmark
+        during directory traversal.
+        This needs to be set it you want stateful directory
+        reading.
+
+    type
+       Directory entry type, should be one of the stat type
+       specifiers (stat.S_IFLNK, stat.S_IFBLK, stat.S_IFDIR,
+       stat.S_IFCHR, stat.S_IFREG, stat.S_IFIFO, stat.S_IFSOCK).
+
+    ino
+       Directory entry inode number.
+
+    Note that Python's standard directory reading interface is
+    stateless and provides only names, so the above optional
+    attributes doesn't make sense in that context.
+    """
+
+    def __init__(self, name, **kw):
+
+        self.name   = name
+        self.offset = 0
+        self.type   = 0
+        self.ino    = 0
+
+        FuseStruct.__init__(self, **kw)
+
+
+class Flock(FuseStruct):
+    """
+    Class for representing flock structures (cf. fcntl(3)).
+    
+    It makes sense to give values to the `l_type`, `l_start`,
+    `l_len`, `l_pid` attributes (`l_whence` is not used by
+    FUSE, see ``fuse.h``).
+    """
+
+    def __init__(self, name, **kw):
+    
+        self.l_type  = None
+        self.l_start = None
+        self.l_len   = None
+        self.l_pid   = None
+ 
+        FuseStruct.__init__(self, **kw)
+
+ 
+class Timespec(FuseStruct):
+    """
+    Cf. struct timespec in time.h:
+    http://www.opengroup.org/onlinepubs/009695399/basedefs/time.h.html
+    """
+
+    def __init__(self, name, **kw):
+    
+        self.tv_sec  = None
+        self.tv_nsec = None
+ 
+        FuseStruct.__init__(self, **kw)
+
+
+class FuseFileInfo(FuseStruct):
+
+    def __init__(self, **kw):
+
+        self.keep      = False
+        self.direct_io = False
+
+        FuseStruct.__init__(self, **kw)
+
+
+
+########## Interface for requiring certain features from your underlying FUSE library.
+
+def feature_needs(*feas):
+    """
+    Get info about the FUSE API version needed for the support of some features.
+
+    This function takes a variable number of feature patterns.
+
+    A feature pattern is either:
+
+    -  an integer (directly referring to a FUSE API version number)
+    -  a built-in feature specifier string (meaning defined by dictionary)
+    -  a string of the form ``has_foo``, where ``foo`` is a filesystem method
+       (refers to the API version where the method has been introduced)
+    -  a list/tuple of other feature patterns (matches each of its members)
+    -  a regexp (meant to be matched against the builtins plus ``has_foo``
+       patterns; can also be given by a string of the from "re:*")
+    -  a negated regexp (can be given by a string of the form "!re:*")
+
+    If called with no arguments, then the list of builtins is returned, mapped
+    to their meaning.
+
+    Otherwise the function returns the smallest FUSE API version number which
+    has all the matching features.
+
+    Builtin specifiers worth to explicit mention:
+    - ``stateful_files``: you want to use custom filehandles (eg. a file class).
+    - ``*``: you want all features.
+    - while ``has_foo`` makes sense for all filesystem method ``foo``, some
+      of these can be found among the builtins, too (the ones which can be
+      handled by the general rule).
+
+    specifiers like ``has_foo`` refer to requirement that the library knows of
+      the fs method ``foo``.
+    """
+
+    fmap = {'stateful_files': 22,
+            'stateful_dirs':  23,
+            'stateful_io':    ('stateful_files', 'stateful_dirs'),
+            'stateful_files_keep_cache': 23,
+            'stateful_files_direct_io': 23,
+            'keep_cache':     ('stateful_files_keep_cache',),
+            'direct_io':      ('stateful_files_direct_io',),
+            'has_opendir':    ('stateful_dirs',),
+            'has_releasedir': ('stateful_dirs',),
+            'has_fsyncdir':   ('stateful_dirs',),
+            'has_create':     25,
+            'has_access':     25,
+            'has_fgetattr':   25,
+            'has_ftruncate':  25,
+            'has_fsinit':     ('has_init'),
+            'has_fsdestroy':  ('has_destroy'),
+            'has_lock':       26,
+            'has_utimens':    26,
+            'has_bmap':       26,
+            'has_init':       23,
+            'has_destroy':    23,
+            '*':              '!re:^\*$'}
+
+    if not feas:
+        return fmap
+
+    def resolve(args, maxva):
+
+        for fp in args:
+            if isinstance(fp, int):
+                maxva[0] = max(maxva[0], fp)
+                continue
+            if isinstance(fp, list) or isinstance(fp, tuple):
+                for f in fp:
+                    yield f
+                continue
+            ma = isinstance(fp, str) and re.compile("(!\s*|)re:(.*)").match(fp)
+            if isinstance(fp, type(re.compile(''))) or ma:
+                neg = False
+                if ma:
+                    mag = ma.groups()
+                    fp = re.compile(mag[1])
+                    neg = bool(mag[0])
+                for f in fmap.keys() + [ 'has_' + a for a in Fuse._attrs ]:
+                    if neg != bool(re.search(fp, f)):
+                        yield f
+                continue
+            ma = re.compile("has_(.*)").match(fp)
+            if ma and ma.groups()[0] in Fuse._attrs and not fp in fmap:
+                yield 21
+                continue
+            yield fmap[fp]
+
+    maxva = [0]
+    while feas:
+        feas = set(resolve(feas, maxva))
+
+    return maxva[0]
+
+
+def APIVersion():
+    """Get the API version of your underlying FUSE lib"""
+
+    return FuseAPIVersion()
+
+
+def feature_assert(*feas):
+    """
+    Takes some feature patterns (like in `feature_needs`).
+    Raises a fuse.FuseError if your underlying FUSE lib fails
+    to have some of the matching features.
+
+    (Note: use a ``has_foo`` type feature assertion only if lib support
+    for method ``foo`` is *necessary* for your fs. Don't use this assertion
+    just because your fs implements ``foo``. The usefulness of ``has_foo``
+    is limited by the fact that we can't guarantee that your FUSE kernel
+    module also supports ``foo``.)
+    """
+
+    fav = APIVersion()
+
+    for fea in feas:
+        fn = feature_needs(fea)
+        if fav < fn:
+            raise FuseError(
+              "FUSE API version %d is required for feature `%s' but only %d is available" % \
+              (fn, str(fea), fav))
+
+
+############# Subclass this.
+
+class Fuse(object):
+    """
+    Python interface to FUSE.
+
+    Basic usage:
+
+    - instantiate
+
+    - add options to `parser` attribute (an instance of `FuseOptParse`)
+
+    - call `parse`
+
+    - call `main`
+    """
+
+    _attrs = ['getattr', 'readlink', 'readdir', 'mknod', 'mkdir',
+              'unlink', 'rmdir', 'symlink', 'rename', 'link', 'chmod',
+              'chown', 'truncate', 'utime', 'open', 'read', 'write', 'release',
+              'statfs', 'fsync', 'create', 'opendir', 'releasedir', 'fsyncdir',
+              'flush', 'fgetattr', 'ftruncate', 'getxattr', 'listxattr',
+              'setxattr', 'removexattr', 'access', 'lock', 'utimens', 'bmap',
+              'fsinit', 'fsdestroy']
+
+    fusage = "%prog [mountpoint] [options]"
+
+    def __init__(self, *args, **kw):
+        """
+        Not much happens here apart from initializing the `parser` attribute.
+        Arguments are forwarded to the constructor of the parser class almost
+        unchanged.
+
+        The parser class is `FuseOptParse` unless you specify one using the
+        ``parser_class`` keyword. (See `FuseOptParse` documentation for
+        available options.)
+        """
+
+        if not fuse_python_api:
+            raise RuntimeError, __name__ + """.fuse_python_api not defined.
+
+! Please define """ + __name__ + """.fuse_python_api internally (eg.
+! 
+! (1)  """ + __name__ + """.fuse_python_api = """ + `FUSE_PYTHON_API_VERSION` + """
+! 
+! ) or in the enviroment (eg. 
+! 
+! (2)  FUSE_PYTHON_API=0.1
+! 
+! ).
+!
+! If you are actually developing a filesystem, probably (1) is the way to go.
+! If you are using a filesystem written before 2007 Q2, probably (2) is what
+! you want."
+"""
+
+        def malformed():
+            raise RuntimeError, \
+                  "malformatted fuse_python_api value " + `fuse_python_api`
+        if not isinstance(fuse_python_api, tuple):
+            malformed()
+        for i in fuse_python_api:
+            if not isinstance(i, int) or i < 0:
+                malformed() 
+
+        if fuse_python_api > FUSE_PYTHON_API_VERSION:
+            raise RuntimeError, """
+! You require FUSE-Python API version """ + `fuse_python_api` + """.
+! However, the latest available is """ + `FUSE_PYTHON_API_VERSION` + """.
+"""
+
+        self.fuse_args = \
+            'fuse_args' in kw and kw.pop('fuse_args') or FuseArgs()
+
+        if get_compat_0_1():
+            return self.__init_0_1__(*args, **kw)
+
+        self.multithreaded = True
+
+        if not 'usage' in kw:
+            kw['usage'] = self.fusage
+        if not 'fuse_args' in kw:
+            kw['fuse_args'] = self.fuse_args
+        kw['fuse'] = self
+        parserclass = \
+          'parser_class' in kw and kw.pop('parser_class') or FuseOptParse
+
+        self.parser = parserclass(*args, **kw)
+        self.methproxy = self.Methproxy()
+
+    def parse(self, *args, **kw):
+        """Parse command line, fill `fuse_args` attribute."""
+
+        ev = 'errex' in kw and kw.pop('errex')
+        if ev and not isinstance(ev, int):
+            raise TypeError, "error exit value should be an integer"
+
+        try:
+            self.cmdline = self.parser.parse_args(*args, **kw)
+        except OptParseError:
+          if ev:
+              sys.exit(ev)
+          raise
+
+        return self.fuse_args
+
+    def main(self, args=None):
+        """Enter filesystem service loop."""
+
+        if get_compat_0_1():
+            args = self.main_0_1_preamble()
+
+        d = {'multithreaded': self.multithreaded and 1 or 0}
+        d['fuse_args'] = args or self.fuse_args.assemble()
+
+        for t in 'file_class', 'dir_class':
+            if hasattr(self, t):
+                getattr(self.methproxy, 'set_' + t)(getattr(self,t))
+
+        for a in self._attrs:
+            b = a
+            if get_compat_0_1() and a in self.compatmap:
+                b = self.compatmap[a]
+            if hasattr(self, b):
+                c = ''
+                if get_compat_0_1() and hasattr(self, a + '_compat_0_1'):
+                    c = '_compat_0_1'
+                d[a] = ErrnoWrapper(self.lowwrap(a + c))
+
+        try:
+            main(**d)
+        except FuseError:
+            if args or self.fuse_args.mount_expected():
+                raise
+
+    def lowwrap(self, fname):
+        """
+        Wraps the fname method when the C code expects a different kind of
+        callback than we have in the fusepy API. (The wrapper is usually for
+        performing some checks or transfromations which could be done in C but
+        is simpler if done in Python.)
+
+        Currently `open` and `create` are wrapped: a boolean flag is added
+        which indicates if the result is to be kept during the opened file's
+        lifetime or can be thrown away. Namely, it's considered disposable
+        if it's an instance of FuseFileInfo.
+        """
+        fun = getattr(self, fname)
+
+        if fname in ('open', 'create'):
+            def wrap(*a, **kw):
+                res = fun(*a, **kw)
+                if not res or type(res) == type(0):
+                    return res
+                else:
+                    return (res, type(res) != FuseFileInfo)
+        elif fname == 'utimens':
+            def wrap(path, acc_sec, acc_nsec, mod_sec, mod_nsec):
+                ts_acc = Timespec(tv_sec = acc_sec, tv_nsec = acc_nsec)
+                ts_mod = Timespec(tv_sec = mod_sec, tv_nsec = mod_nsec)
+                return fun(path, ts_acc, ts_mod)
+        else:
+            wrap = fun
+
+        return wrap
+
+    def GetContext(self):
+        return FuseGetContext(self)
+
+    def Invalidate(self, path):
+        return FuseInvalidate(self, path)
+
+    def fuseoptref(cls):
+        """
+        Find out which options are recognized by the library.
+        Result is a `FuseArgs` instance with the list of supported
+        options, suitable for passing on to the `filter` method of
+        another `FuseArgs` instance.
+        """
+
+        import os, re
+
+        pr, pw = os.pipe()
+        pid = os.fork()
+        if pid == 0:
+             os.dup2(pw, 2)
+             os.close(pr)
+
+             fh = cls()
+             fh.fuse_args = FuseArgs()
+             fh.fuse_args.setmod('showhelp')
+             fh.main()
+             sys.exit()
+
+        os.close(pw)
+
+        fa = FuseArgs()
+        ore = re.compile("-o\s+([\w\[\]]+(?:=\w+)?)")
+        fpr = os.fdopen(pr)
+        for l in fpr:
+             m = ore.search(l)
+             if m:
+                 o = m.groups()[0]
+                 oa = [o]
+                 # try to catch two-in-one options (like "[no]foo")
+                 opa = o.split("[")
+                 if len(opa) == 2:
+                    o1, ox = opa
+                    oxpa = ox.split("]")
+                    if len(oxpa) == 2:
+                       oo, o2 = oxpa
+                       oa = [o1 + o2, o1 + oo + o2]
+                 for o in oa:
+                     fa.add(o)
+
+        fpr.close()
+        return fa
+
+    fuseoptref = classmethod(fuseoptref)
+
+
+    class Methproxy(object):
+
+        def __init__(self):
+
+            class mpx(object):
+               def __init__(self, name):
+                   self.name = name
+               def __call__(self, *a, **kw):
+                   return getattr(a[-1], self.name)(*(a[1:-1]), **kw)
+
+            self.proxyclass = mpx
+            self.mdic = {}
+            self.file_class = None
+            self.dir_class = None
+
+        def __call__(self, meth):
+            return meth in self.mdic and self.mdic[meth] or None
+
+        def _add_class_type(cls, type, inits, proxied):
+
+            def setter(self, xcls):
+
+                setattr(self, type + '_class', xcls)
+
+                for m in inits:
+                    self.mdic[m] = xcls
+
+                for m in proxied:
+                    if hasattr(xcls, m):
+                        self.mdic[m] = self.proxyclass(m)
+
+            setattr(cls, 'set_' + type + '_class', setter)
+
+        _add_class_type = classmethod(_add_class_type)
+
+    Methproxy._add_class_type('file', ('open', 'create'),
+                              ('read', 'write', 'fsync', 'release', 'flush',
+                               'fgetattr', 'ftruncate', 'lock'))
+    Methproxy._add_class_type('dir', ('opendir',),
+                              ('readdir', 'fsyncdir', 'releasedir'))
+
+
+    def __getattr__(self, meth):
+
+        m = self.methproxy(meth)
+        if m:
+            return m
+
+        raise AttributeError, "Fuse instance has no attribute '%s'" % meth
+
+
+
+##########
+###
+###  Compat stuff.
+###
+##########
+
+
+
+    def __init_0_1__(self, *args, **kw):
+
+        self.flags = 0
+        multithreaded = 0
+
+        # default attributes
+        if args == ():
+            # there is a self.optlist.append() later on, make sure it won't
+            # bomb out.
+            self.optlist = []
+        else:
+            self.optlist = args
+        self.optdict = kw
+
+        if len(self.optlist) == 1:
+            self.mountpoint = self.optlist[0]
+        else:
+            self.mountpoint = None
+
+        # grab command-line arguments, if any.
+        # Those will override whatever parameters
+        # were passed to __init__ directly.
+        argv = sys.argv
+        argc = len(argv)
+        if argc > 1:
+            # we've been given the mountpoint
+            self.mountpoint = argv[1]
+        if argc > 2:
+            # we've received mount args
+            optstr = argv[2]
+            opts = optstr.split(",")
+            for o in opts:
+                try:
+                    k, v = o.split("=", 1)
+                    self.optdict[k] = v
+                except:
+                    self.optlist.append(o)
+
+
+    def main_0_1_preamble(self):
+
+        cfargs = FuseArgs()
+
+        cfargs.mountpoint = self.mountpoint
+
+        if hasattr(self, 'debug'):
+            cfargs.add('debug')
+
+        if hasattr(self, 'allow_other'):
+            cfargs.add('allow_other')
+
+        if hasattr(self, 'kernel_cache'):
+            cfargs.add('kernel_cache')
+
+        return cfargs.assemble()
+
+
+    def getattr_compat_0_1(self, *a):
+        from os import stat_result
+
+        return stat_result(self.getattr(*a))
+
+
+    def statfs_compat_0_1(self, *a):
+
+        oout = self.statfs(*a)
+        lo = len(oout)
+
+        svf = StatVfs()
+        svf.f_bsize   = oout[0]                   # 0
+        svf.f_frsize  = oout[lo >= 8 and 7 or 0]  # 1
+        svf.f_blocks  = oout[1]                   # 2
+        svf.f_bfree   = oout[2]                   # 3
+        svf.f_bavail  = oout[3]                   # 4
+        svf.f_files   = oout[4]                   # 5
+        svf.f_ffree   = oout[5]                   # 6
+        svf.f_favail  = lo >= 9 and oout[8] or 0  # 7
+        svf.f_flag    = lo >= 10 and oout[9] or 0 # 8
+        svf.f_namemax = oout[6]                   # 9
+
+        return svf
+
+
+    def readdir_compat_0_1(self, path, offset, *fh):
+
+        for name, type in self.getdir(path):
+            de = Direntry(name)
+            de.type = type
+
+            yield de
+
+
+    compatmap = {'readdir': 'getdir'}

mac/macfuse/fuseparts/__init__.py

@@ -0,0 +1 @@
+__version__ = "0.2"

mac/macfuse/fuseparts/setcompatwrap.py

@@ -0,0 +1,5 @@
+try:
+  set()
+  set = set
+except:
+  from sets import Set as set

mac/macfuse/fuseparts/subbedopts.py

@@ -0,0 +1,268 @@
+#
+#    Copyright (C) 2006  Csaba Henk  <csaba.henk@creo.hu>
+#
+#    This program can be distributed under the terms of the GNU LGPL.
+#    See the file COPYING.
+#
+
+from optparse import Option, OptionParser, OptParseError, OptionConflictError
+from optparse import HelpFormatter, IndentedHelpFormatter, SUPPRESS_HELP
+from fuseparts.setcompatwrap import set
+
+##########
+###
+###  Generic suboption parsing stuff.
+###
+##########
+
+
+
+class SubOptsHive(object):
+    """
+    Class for collecting unhandled suboptions.
+    """
+
+    def __init__(self):
+
+        self.optlist = set()
+        self.optdict = {}
+
+    def _str_core(self):
+
+        sa = []
+        for k, v in self.optdict.iteritems():
+             sa.append(str(k) + '=' + str(v))
+
+        ra = (list(self.optlist) + sa) or ["(none)"]
+        ra.sort()
+        return ra 
+
+    def __str__(self):
+        return "< opts: " + ", ".join(self._str_core()) + " >"
+
+    def canonify(self):
+        """
+        Transform self to an equivalent canonical form:
+        delete optdict keys with False value, move optdict keys
+        with True value to optlist, stringify other values.
+        """
+
+        for k, v in self.optdict.iteritems():
+            if v == False:
+                self.optdict.pop(k)
+            elif v == True:
+                self.optdict.pop(k)
+                self.optlist.add(v)
+            else:
+                self.optdict[k] = str(v)
+
+    def filter(self, other):
+        """
+        Throw away those options which are not in the other one.
+        Returns a new instance with the rejected options.
+        """
+
+        self.canonify()
+        other.canonify()
+
+        rej = self.__class__()
+        rej.optlist = self.optlist.difference(other.optlist)
+        self.optlist.difference_update(rej.optlist)
+        for x in self.optdict.copy():
+             if x not in other.optdict:
+                 self.optdict.pop(x)
+                 rej.optdict[x] = None
+
+        return rej
+
+    def add(self, opt, val=None):
+        """Add a suboption."""
+
+        ov = opt.split('=', 1)
+        o = ov[0]
+        v = len(ov) > 1 and ov[1] or None
+
+        if (v):
+            if val != None:
+                raise AttributeError, "ambiguous option value"
+            val = v
+
+        if val == False:
+            return
+
+        if val in (None, True):
+            self.optlist.add(o)
+        else:
+            self.optdict[o] = val
+
+
+
+class SubbedOpt(Option):
+    """
+    `Option` derivative enhanced with the attribute of being a suboption of
+     some other option (like ``foo`` and ``bar`` for ``-o`` in ``-o foo,bar``).
+    """
+
+    ATTRS = Option.ATTRS + ["subopt", "subsep", "subopts_hive"]
+    ACTIONS = Option.ACTIONS + ("store_hive",)
+    STORE_ACTIONS = Option.STORE_ACTIONS + ("store_hive",)
+    TYPED_ACTIONS = Option.TYPED_ACTIONS + ("store_hive",)
+
+    def __init__(self, *opts, **attrs):
+
+       self.subopt_map = {}
+
+       if "subopt" in attrs:
+           self._short_opts = []
+           self._long_opts = []
+           self._set_opt_strings(opts)
+           self.baseopt = self._short_opts[0] or self._long_opts[0]
+           opts = ()
+
+       Option.__init__(self, *opts, **attrs)
+
+    def __str__(self):
+        pf = ""
+        if hasattr(self, "subopt") and self.subopt:
+            pf = " %s...,%s,..." % (self.baseopt, self.subopt)
+        return Option.__str__(self) + pf
+
+    def _check_opt_strings(self, opts):
+        return opts
+
+    def _check_dest(self):
+        try:
+            Option._check_dest(self)
+        except IndexError:
+            if self.subopt:
+                self.dest = "__%s__%s" % (self.baseopt, self.subopt)
+                self.dest = self.dest.replace("-", "")
+            else:
+                raise
+
+    def get_opt_string(self):
+        if hasattr(self, 'subopt'):
+            return self.subopt
+        else:
+            return Option.get_opt_string(self)
+
+    def take_action(self, action, dest, opt, value, values, parser):
+        if action == "store_hive":
+            if not hasattr(values, dest) or getattr(values, dest) == None:
+                 if hasattr(self, "subopts_hive") and self.subopts_hive:
+                     hive = self.subopts_hive
+                 else:
+                     hive = parser.hive_class()
+                 setattr(values, dest, hive)
+            for o in value.split(self.subsep or ","):
+                oo = o.split('=')
+                ok = oo[0]
+                ov = None
+                if (len(oo) > 1):
+                    ov = oo[1]
+                if ok in self.subopt_map:
+                    self.subopt_map[ok].process(ok, ov, values, parser)
+                else:
+                    getattr(values, dest).add(*oo)
+            return
+        Option.take_action(self, action, dest, opt, value, values, parser)
+
+    def register_sub(self, o):
+        """Register argument a suboption for `self`."""
+
+        if o.subopt in self.subopt_map:
+            raise OptionConflictError(
+              "conflicting suboption handlers for `%s'" % o.subopt,
+              o)
+        self.subopt_map[o.subopt] = o
+
+    CHECK_METHODS = []
+    for m in Option.CHECK_METHODS:
+        #if not m == Option._check_dest:
+        if not m.__name__ == '_check_dest':
+            CHECK_METHODS.append(m)
+    CHECK_METHODS.append(_check_dest)
+
+
+
+class SubbedOptFormatter(HelpFormatter):
+
+    def format_option_strings(self, option):
+        if hasattr(option, "subopt") and option.subopt:
+            res = '-o ' + option.subopt
+            if option.takes_value():
+                res += "="
+                res += option.metavar or 'FOO'
+            return res
+
+        return HelpFormatter.format_option_strings(self, option)
+
+
+
+class SubbedOptIndentedFormatter(IndentedHelpFormatter, SubbedOptFormatter):
+
+    def format_option_strings(self, option):
+        return SubbedOptFormatter.format_option_strings(self, option)
+
+
+
+class SubbedOptParse(OptionParser):
+    """
+    This class alters / enhances `OptionParser` with *suboption handlers*.
+
+    That is, calling `sop.add_option('-x', subopt=foo)` installs a handler
+    which will be triggered if there is ``-x foo`` in the command line being
+    parsed (or, eg., ``-x foo,bar``).
+
+    Moreover, ``-x`` implicitly gets a handler which collects the unhandled
+    suboptions of ``-x`` into a `SubOptsHive` instance (accessible post festam
+    via the `x` attribute of the returned Values object). (The only exception
+    is when ``-x`` has *explicitly*  been added with action ``store_hive``.
+    This opens up the possibility of customizing the ``-x`` handler at some
+    rate.)
+
+    Suboption handlers have all the nice features of normal option handlers,
+    eg. they are displayed in the automatically generated help message
+    (and can have their own help info).
+    """
+
+    def __init__(self, *args, **kw):
+
+         if not 'formatter' in kw:
+             kw['formatter'] = SubbedOptIndentedFormatter()
+         if not 'option_class' in kw:
+             kw['option_class'] = SubbedOpt
+         if 'hive_class' in kw:
+             self.hive_class = kw.pop('hive_class')
+         else:
+             self.hive_class = SubOptsHive
+
+         OptionParser.__init__(self, *args, **kw)
+
+    def add_option(self, *args, **kwargs):
+        if 'action' in kwargs and kwargs['action'] == 'store_hive':
+            if 'subopt' in kwargs:
+                raise OptParseError(
+                  """option can't have a `subopt' attr and `action="store_hive"' at the same time""")
+            if not 'type' in kwargs:
+                kwargs['type'] = 'string'
+        elif 'subopt' in kwargs:
+            o = self.option_class(*args, **kwargs)
+
+            oo = self.get_option(o.baseopt)
+            if oo:
+                if oo.action != "store_hive":
+                    raise OptionConflictError(
+                      "can't add subopt as option has already a handler that doesn't do `store_hive'",
+                      oo)
+            else:
+                self.add_option(o.baseopt, action='store_hive',
+                                metavar="sub1,[sub2,...]")
+                oo = self.get_option(o.baseopt)
+
+            oo.register_sub(o)
+
+            args = (o,)
+            kwargs = {}
+
+        return OptionParser.add_option(self, *args, **kwargs)

mac/macfuse/tahoefuse.py

@@ -0,0 +1,659 @@
+#!/usr/bin/env python
+
+#-----------------------------------------------------------------------------------------------
+from allmydata.uri import CHKFileURI, NewDirectoryURI, LiteralFileURI
+from allmydata.scripts.common_http import do_http as do_http_req
+
+import base64
+import sha
+import os
+import errno
+import stat
+# pull in some spaghetti to make this stuff work without fuse-py being installed
+try:
+    import _find_fuse_parts
+    junk = _find_fuse_parts
+    del junk
+except ImportError:
+    pass
+import fuse
+
+import time
+import traceback
+import simplejson
+import urllib
+
+if not hasattr(fuse, '__version__'):
+    raise RuntimeError, \
+        "your fuse-py doesn't know of fuse.__version__, probably it's too old."
+
+fuse.fuse_python_api = (0, 2)
+fuse.feature_assert('stateful_files', 'has_init')
+
+
+logfile = file('tfuse.log', 'wb')
+
+def log(msg):
+    logfile.write("%s: %s\n" % (time.asctime(), msg))
+    #time.sleep(0.1)
+    logfile.flush()
+
+fuse.flog = log
+
+def do_http(method, url, body=''):
+    resp = do_http_req(method, url, body)
+    log('do_http(%s, %s) -> %s, %s' % (method, url, resp.status, resp.reason))
+    if resp.status not in (200, 201):
+        raise RuntimeError('http response (%s, %s)' % (resp.status, resp.reason))
+    else:
+        return resp.read()
+
+def flag2mode(flags):
+    log('flag2mode(%r)' % (flags,))
+    #md = {os.O_RDONLY: 'r', os.O_WRONLY: 'w', os.O_RDWR: 'w+'}
+    md = {os.O_RDONLY: 'rb', os.O_WRONLY: 'wb', os.O_RDWR: 'w+b'}
+    m = md[flags & (os.O_RDONLY | os.O_WRONLY | os.O_RDWR)]
+
+    if flags | os.O_APPEND:
+        m = m.replace('w', 'a', 1)
+
+    return m
+
+def logargsretexc(meth):
+    def inner(self, *args, **kwargs):
+        log("%s(%r, %r)" % (meth, args, kwargs))
+        try:
+            ret = meth(self, *args, **kwargs)
+        except:
+            log('exception:\n%s' % (traceback.format_exc(),))
+            raise
+        log("ret: %r" % (ret, ))
+        return ret
+    inner.__name__ = '<logwrap(%s)>' % (meth,)
+    return inner
+
+def logexc(meth):
+    def inner(self, *args, **kwargs):
+        try:
+            ret = meth(self, *args, **kwargs)
+        except:
+            log('exception:\n%s' % (traceback.format_exc(),))
+            raise
+        return ret
+    inner.__name__ = '<logwrap(%s)>' % (meth,)
+    return inner
+
+def log_exc():
+    log('exception:\n%s' % (traceback.format_exc(),))
+
+class TahoeFuseFile(object):
+
+    def __init__(self, path, flags, *mode):
+        log("TFF: __init__(%r, %r, %r)" % (path, flags, mode))
+
+        self._path = path # for tahoe put
+        try:
+            self.parent, self.name, self.fnode = self.tfs.get_parent_name_and_child(path)
+            m = flag2mode(flags)
+            log('TFF: flags2(mode) -> %s' % (m,))
+            if m[0] in 'wa':
+                # write
+                self.fname = self.tfs.cache.tmp_file(os.urandom(20))
+                if self.fnode is None:
+                    log('TFF: [%s] open(%s) for write: no such file, creating new File' % (self.name, self.fname, ))
+                    self.fnode = File(0, None)
+                    self.fnode.tmp_fname = self.fname # XXX kill this
+                    self.parent.add_child(self.name, self.fnode)
+                elif hasattr(self.fnode, 'tmp_fname'):
+                    self.fname = self.fnode.tmp_fname
+                self.file = os.fdopen(os.open(self.fname, flags, *mode), m)
+                self.fd = self.file.fileno()
+                log('TFF: opened(%s) for write' % self.fname)
+                self.open_for_write = True
+            else:
+                # read
+                assert self.fnode is not None
+                uri = self.fnode.get_uri()
+
+                # XXX make this go away
+                if hasattr(self.fnode, 'tmp_fname'):
+                    self.fname = self.fnode.tmp_fname
+                    log('TFF: reopening(%s) for reading' % self.fname)
+                else:
+                    log('TFF: fetching file from cache for reading')
+                    self.fname = self.tfs.cache.get_file(uri)
+
+                self.file = os.fdopen(os.open(self.fname, flags, *mode), m)
+                self.fd = self.file.fileno()
+                self.open_for_write = False
+                log('TFF: opened(%s) for read' % self.fname)
+        except:
+            log_exc()
+            raise
+
+    def log(self, msg):
+        log("<TFF(%s:%s)> %s" % (os.path.basename(self.fname), self.name, msg))
+
+    @logexc
+    def read(self, size, offset):
+        self.log('read(%r, %r)' % (size, offset, ))
+        self.file.seek(offset)
+        return self.file.read(size)
+
+    @logexc
+    def write(self, buf, offset):
+        self.log("write(-%s-, %r)" % (len(buf), offset))
+        if not self.open_for_write:
+            return -errno.EACCES
+        self.file.seek(offset)
+        self.file.write(buf)
+        return len(buf)
+
+    @logexc
+    def release(self, flags):
+        self.log("release(%r)" % (flags,))
+        self.file.close()
+        if self.open_for_write:
+            size = os.path.getsize(self.fname)
+            self.fnode.size = size
+            file_cap = self.tfs.upload(self.fname)
+            self.fnode.ro_uri = file_cap
+            self.tfs.add_child(self.parent.get_uri(), self.name, file_cap)
+            self.log("uploaded: %s" % (file_cap,))
+
+        # dbg
+        print_tree()
+
+    def _fflush(self):
+        if 'w' in self.file.mode or 'a' in self.file.mode:
+            self.file.flush()
+
+    @logexc
+    def fsync(self, isfsyncfile):
+        self.log("fsync(%r)" % (isfsyncfile,))
+        self._fflush()
+        if isfsyncfile and hasattr(os, 'fdatasync'):
+            os.fdatasync(self.fd)
+        else:
+            os.fsync(self.fd)
+
+    @logexc
+    def flush(self):
+        self.log("flush()")
+        self._fflush()
+        # cf. xmp_flush() in fusexmp_fh.c
+        os.close(os.dup(self.fd))
+
+    @logexc
+    def fgetattr(self):
+        self.log("fgetattr()")
+        s = os.fstat(self.fd)
+        self.log("fgetattr() -> %r" % (s,))
+        return s
+
+    @logexc
+    def ftruncate(self, len):
+        self.log("ftruncate(%r)" % (len,))
+        self.file.truncate(len)
+
+class ObjFetcher(object):
+    def get_tahoe_file(self, path, flags, *mode):
+        log('objfetcher.get_tahoe_file(%r, %r, %r, %r)' % (self, path, flags, mode))
+        return TahoeFuseFile(path, flags, *mode)
+fetcher = ObjFetcher()
+
+class TahoeFuse(fuse.Fuse):
+
+    def __init__(self, tfs, *args, **kw):
+        log("TF: __init__(%r, %r)" % (args, kw))
+
+        self.tfs = tfs
+        class MyFuseFile(TahoeFuseFile):
+            tfs = tfs
+        self.file_class = MyFuseFile
+        log("TF: file_class: %r" % (self.file_class,))
+
+        fuse.Fuse.__init__(self, *args, **kw)
+
+        #import thread
+        #thread.start_new_thread(self.launch_reactor, ())
+
+    def log(self, msg):
+        log("<TF> %s" % (msg, ))
+
+    @logexc
+    def readlink(self, path):
+        self.log("readlink(%r)" % (path,))
+        return -errno.EOPNOTSUPP
+
+    @logexc
+    def unlink(self, path):
+        self.log("unlink(%r)" % (path,))
+        return -errno.EOPNOTSUPP
+
+    @logexc
+    def rmdir(self, path):
+        self.log("rmdir(%r)" % (path,))
+        return -errno.EOPNOTSUPP
+
+    @logexc
+    def symlink(self, path, path1):
+        self.log("symlink(%r, %r)" % (path, path1))
+        return -errno.EOPNOTSUPP
+
+    @logexc
+    def rename(self, path, path1):
+        self.log("rename(%r, %r)" % (path, path1))
+        self.tfs.rename(path, path1)
+
+    @logexc
+    def link(self, path, path1):
+        self.log("link(%r, %r)" % (path, path1))
+        return -errno.EOPNOTSUPP
+
+    @logexc
+    def chmod(self, path, mode):
+        self.log("chmod(%r, %r)" % (path, mode))
+        return -errno.EOPNOTSUPP
+
+    @logexc
+    def chown(self, path, user, group):
+        self.log("chown(%r, %r, %r)" % (path, user, group))
+        return -errno.EOPNOTSUPP
+
+    @logexc
+    def truncate(self, path, len):
+        self.log("truncate(%r, %r)" % (path, len))
+        return -errno.EOPNOTSUPP
+
+    @logexc
+    def utime(self, path, times):
+        self.log("utime(%r, %r)" % (path, times))
+        return -errno.EOPNOTSUPP
+
+    @logexc
+    def statfs(self):
+        self.log("statfs()")
+        """
+        Should return an object with statvfs attributes (f_bsize, f_frsize...).
+        Eg., the return value of os.statvfs() is such a thing (since py 2.2).
+        If you are not reusing an existing statvfs object, start with
+        fuse.StatVFS(), and define the attributes.
+
+        To provide usable information (ie., you want sensible df(1)
+        output, you are suggested to specify the following attributes:
+
+            - f_bsize - preferred size of file blocks, in bytes
+            - f_frsize - fundamental size of file blcoks, in bytes
+                [if you have no idea, use the same as blocksize]
+            - f_blocks - total number of blocks in the filesystem
+            - f_bfree - number of free blocks
+            - f_files - total number of file inodes
+            - f_ffree - nunber of free file inodes
+        """
+
+        return os.statvfs(".")
+
+    def fsinit(self):
+        self.log("fsinit()")
+
+    def main(self, *a, **kw):
+        self.log("main(%r, %r)" % (a, kw))
+
+        return fuse.Fuse.main(self, *a, **kw)
+
+    ##################################################################
+
+    @logexc
+    def readdir(self, path, offset):
+        log('readdir(%r, %r)' % (path, offset))
+        node = self.tfs.get_path(path)
+        if node is None:
+            return -errno.ENOENT
+        dirlist = ['.', '..'] + node.children.keys()
+        log('dirlist = %r' % (dirlist,))
+        return [fuse.Direntry(d) for d in dirlist]
+
+    @logexc
+    def getattr(self, path):
+        log('getattr(%r)' % (path,))
+        node = self.tfs.get_path(path)
+        if node is None:
+            return -errno.ENOENT
+        return node.get_stat()
+
+    @logexc
+    def access(self, path, mode):
+        self.log("access(%r, %r)" % (path, mode))
+        node = self.tfs.get_path(path)
+        if not node:
+            return -errno.ENOENT
+        accmode = os.O_RDONLY | os.O_WRONLY | os.O_RDWR
+        if (mode & 0222):
+            if not node.writable():
+                log('write access denied for %s (req:%o)' % (path, mode, ))
+                return -errno.EACCES
+        #else:
+            #log('access granted for %s' % (path, ))
+
+    @logexc
+    def mkdir(self, path, mode):
+        self.log("mkdir(%r, %r)" % (path, mode))
+        self.tfs.mkdir(path)
+
+def main(tfs):
+
+    usage = "Userspace tahoe fs: cache a tahoe tree and present via fuse\n" + fuse.Fuse.fusage
+
+    server = TahoeFuse(tfs, version="%prog " + fuse.__version__,
+                       usage=usage,
+                       dash_s_do='setsingle')
+    server.parse(errex=1)
+    server.main()
+
+
+def getbasedir():
+    f = file(os.path.expanduser("~/.tahoe/private/root_dir.cap"), 'rb')
+    bd = f.read().strip()
+    f.close()
+    return bd
+
+def getnodeurl():
+    f = file(os.path.expanduser("~/.tahoe/node.url"), 'rb')
+    nu = f.read().strip()
+    f.close()
+    if nu[-1] != "/":
+        nu += "/"
+    return nu
+
+def fingerprint(uri):
+    if uri is None:
+        return None
+    return base64.b32encode(sha.new(uri).digest()).lower()[:6]
+
+class TStat(fuse.Stat):
+    def __init__(self, **kwargs):
+        fuse.Stat.__init__(self, **kwargs)
+
+    def __repr__(self):
+        return "<Stat%r" % {
+            'st_mode': self.st_mode,
+            'st_ino': self.st_ino,
+            'st_dev': self.st_dev,
+            'st_nlink': self.st_nlink,
+            'st_uid': self.st_uid,
+            'st_gid': self.st_gid,
+            'st_size': self.st_size,
+            'st_atime': self.st_atime,
+            'st_mtime': self.st_mtime,
+            'st_ctime': self.st_ctime,
+            }
+
+class Directory(object):
+    def __init__(self, ro_uri, rw_uri):
+        self.ro_uri = ro_uri
+        self.rw_uri = rw_uri
+        assert (rw_uri or ro_uri)
+        self.children = {}
+
+    def __repr__(self):
+        return "<Directory %s>" % (fingerprint(self.get_uri()),)
+
+    def get_children(self):
+        return self.children.keys()
+
+    def get_child(self, name):
+        return self.children[name]
+
+    def add_child(self, name, file_node):
+        self.children[name] = file_node
+
+    def remove_child(self, name):
+        del self.children[name]
+
+    def get_uri(self):
+        return self.rw_uri or self.ro_uri
+
+    def writable(self):
+        return self.rw_uri and self.rw_uri != self.ro_uri
+
+    def pprint(self, prefix='', printed=None):
+        ret = []
+        if printed is None:
+            printed = set()
+        writable = self.writable() and '+' or ' '
+        if self in printed:
+            ret.append("         %s/%s ... <%s>" % (prefix, writable, fingerprint(self.get_uri()), ))
+        else:
+            ret.append("[%s] %s/%s" % (fingerprint(self.get_uri()), prefix, writable, ))
+            printed.add(self)
+            for name,f in sorted(self.children.items()):
+                ret.append(f.pprint(' ' * (len(prefix)+1)+name, printed))
+        return '\n'.join(ret)
+
+    def get_stat(self):
+        s = TStat(st_mode = stat.S_IFDIR | 0755, st_nlink = 2)
+        log("%s.get_stat()->%s" % (self, s))
+        return s
+
+class File(object):
+    def __init__(self, size, ro_uri):
+        self.size = size
+        if ro_uri:
+            ro_uri = str(ro_uri)
+        self.ro_uri = ro_uri
+
+    def __repr__(self):
+        return "<File %s>" % (fingerprint(self.ro_uri) or [self.tmp_fname],)
+
+    def pprint(self, prefix='', printed=None):
+        return "         %s (%s)" % (prefix, self.size, )
+
+    def get_stat(self):
+        if hasattr(self, 'tmp_fname'):
+            s = os.stat(self.tmp_fname)
+            log("%s.get_stat()->%s" % (self, s))
+        else:
+            s = TStat(st_size=self.size, st_mode = stat.S_IFREG | 0444, st_nlink = 1)
+            log("%s.get_stat()->%s" % (self, s))
+        return s
+
+    def get_uri(self):
+        return self.ro_uri
+
+    def writable(self):
+        #return not self.ro_uri
+        return True
+
+class TFS(object):
+    def __init__(self, nodeurl, root_uri):
+        self.nodeurl = nodeurl
+        self.root_uri = root_uri
+        self.dirs = {}
+
+        self.cache = FileCache(nodeurl, os.path.expanduser('~/.tahoe/_cache'))
+        ro_uri = NewDirectoryURI.init_from_string(self.root_uri).get_readonly()
+        self.root = Directory(ro_uri, self.root_uri)
+        self.load_dir('<root>', self.root)
+
+    def log(self, msg):
+        log("<TFS> %s" % (msg, ))
+
+    def pprint(self):
+        return self.root.pprint()
+
+    def get_parent_name_and_child(self, path):
+        dirname, name = os.path.split(path)
+        parent = self.get_path(dirname)
+        try:
+            child = parent.get_child(name)
+            return parent, name, child
+        except KeyError:
+            return parent, name, None
+        
+    def get_path(self, path):
+        comps = path.strip('/').split('/')
+        if comps == ['']:
+            comps = []
+        cursor = self.root
+        for comp in comps:
+            if not isinstance(cursor, Directory):
+                self.log('path "%s" is not a dir' % (path,))
+                return None
+            try:
+                cursor = cursor.children[comp]
+            except KeyError:
+                self.log('path "%s" not found' % (path,))
+                return None
+        return cursor
+
+    def load_dir(self, name, dirobj):
+        print 'loading', name, dirobj
+        url = self.nodeurl + "uri/%s?t=json" % urllib.quote(dirobj.get_uri())
+        data = urllib.urlopen(url).read()
+        parsed = simplejson.loads(data)
+        nodetype, d = parsed
+        assert nodetype == 'dirnode'
+        for name,details in d['children'].items():
+            name = str(name)
+            ctype, cattrs = details
+            if ctype == 'dirnode':
+                cobj = self.dir_for(name, cattrs.get('ro_uri'), cattrs.get('rw_uri'))
+            else:
+                assert ctype == "filenode"
+                cobj = File(cattrs.get('size'), cattrs.get('ro_uri'))
+            dirobj.children[name] = cobj
+
+    def dir_for(self, name, ro_uri, rw_uri):
+        if ro_uri:
+            ro_uri = str(ro_uri)
+        if rw_uri:
+            rw_uri = str(rw_uri)
+        uri = rw_uri or ro_uri
+        assert uri
+        dirobj = self.dirs.get(uri)
+        if not dirobj:
+            dirobj = Directory(ro_uri, rw_uri)
+            self.dirs[uri] = dirobj
+            self.load_dir(name, dirobj)
+        return dirobj
+
+    def upload(self, fname):
+        self.log('upload(%r)' % (fname,))
+        fh = file(fname, 'rb')
+        url = self.nodeurl + "uri"
+        file_cap = do_http('PUT', url, fh)
+        self.log('uploaded to: %r' % (file_cap,))
+        return file_cap
+
+    def add_child(self, parent_dir_uri, child_name, child_uri):
+        self.log('add_child(%r, %r, %r)' % (parent_dir_uri, child_name, child_uri,))
+        url = self.nodeurl + "uri/%s/%s?t=uri" % (urllib.quote(parent_dir_uri), urllib.quote(child_name), )
+        child_cap = do_http('PUT', url, child_uri)
+        assert child_cap == child_uri
+        self.log('added child %r with %r to %r' % (child_name, child_uri, parent_dir_uri))
+        return child_uri
+
+    def remove_child(self, parent_uri, child_name):
+        self.log('remove_child(%r, %r)' % (parent_uri, child_name, ))
+        url = self.nodeurl + "uri/%s/%s" % (urllib.quote(parent_uri), urllib.quote(child_name))
+        resp = do_http('DELETE', url)
+        self.log('child removal yielded %r' % (resp,))
+
+    def mkdir(self, path):
+        self.log('mkdir(%r)' % (path,))
+        url = self.nodeurl + "uri?t=mkdir"
+        new_dir_cap = do_http('PUT', url)
+        parent_path, name = os.path.split(path)
+        self.log('parent_path, name = %s, %s' % (parent_path, name,))
+        parent = self.get_path(parent_path)
+        self.log('parent = %s' % (parent, ))
+        self.log('new_dir_cap = %s' % (new_dir_cap, ))
+        child_uri = self.add_child(parent.get_uri(), name, new_dir_cap)
+        ro_uri = NewDirectoryURI.init_from_string(child_uri).get_readonly()
+        child = Directory(ro_uri, child_uri)
+        parent.add_child(name, child)
+
+    def rename(self, path, path1):
+        self.log('rename(%s, %s)' % (path, path1))
+        parent, name, child = self.get_parent_name_and_child(path)
+        child_uri = child.get_uri()
+        new_parent_path, new_child_name = os.path.split(path1)
+        new_parent = self.get_path(new_parent_path)
+        self.add_child(new_parent.get_uri(), new_child_name, child_uri)
+        self.remove_child(parent.get_uri(), name)
+        parent.remove_child(name)
+        new_parent.add_child(new_child_name, child)
+
+class FileCache(object):
+    def __init__(self, nodeurl, cachedir):
+        self.nodeurl = nodeurl
+        self.cachedir = cachedir
+        if not os.path.exists(self.cachedir):
+            os.makedirs(self.cachedir)
+        self.tmpdir = os.path.join(self.cachedir, 'tmp')
+        if not os.path.exists(self.tmpdir):
+            os.makedirs(self.tmpdir)
+
+    def log(self, msg):
+        log("<FC> %s" % (msg, ))
+
+    def get_file(self, uri):
+        self.log('get_file(%s)' % (uri,))
+        if uri.startswith("URI:LIT"):
+            return self.get_literal(uri)
+        else:
+            return self.get_chk(uri)
+
+    def get_literal(self, uri):
+        h = sha.new(uri).digest()
+        u = LiteralFileURI.init_from_string(uri)
+        fname = os.path.join(self.cachedir, '__'+base64.b32encode(h).lower())
+        size = len(u.data)
+        self.log('writing literal file %s (%s)' % (fname, size, ))
+        fh = open(fname, 'wb')
+        fh.write(u.data)
+        fh.close()
+        return fname
+
+    def get_chk(self, uri):
+        u = CHKFileURI.init_from_string(str(uri))
+        storage_index = u.storage_index
+        size = u.size
+        fname = os.path.join(self.cachedir, base64.b32encode(storage_index).lower())
+        if os.path.exists(fname):
+            fsize = os.path.getsize(fname)
+            if fsize == size:
+                return fname
+            else:
+                self.log('warning file "%s" is too short %s < %s' % (fname, fsize, size))
+        self.log('downloading file %s (%s)' % (fname, size, ))
+        fh = open(fname, 'wb')
+        url = "%suri/%s" % (self.nodeurl, uri)
+        download = urllib.urlopen(''.join([ self.nodeurl, "uri/", uri ]))
+        while True:
+            chunk = download.read(4096)
+            if not chunk:
+                break
+            fh.write(chunk)
+        fh.close()
+        return fname
+
+    def tmp_file(self, id):
+        fname = os.path.join(self.tmpdir, base64.b32encode(id).lower())
+        return fname
+
+def print_tree():
+    log('tree:\n' + _tfs.pprint())
+
+if __name__ == '__main__':
+    log("\n\nmain()")
+    tfs = TFS(getnodeurl(), getbasedir())
+    print tfs.pprint()
+
+    # make tfs instance accesible to print_tree() for dbg
+    global _tfs
+    _tfs = tfs
+
+    main(tfs)
+