Example File Systems¶
Python-LLFUSE comes with several example file systems in the
examples directory of the release tarball. For completeness,
these examples are also included here.
Single-file, Read-only File System¶
(shipped as examples/lltest.py)
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 | #!/usr/bin/env python3
'''
lltest.py - Example file system for Python-LLFUSE.
This program presents a static file system containing a single file. It is
compatible with both Python 2.x and 3.x. Based on an example from Gerion Entrup.
Copyright © 2015 Nikolaus Rath <Nikolaus.org>
Copyright © 2015 Gerion Entrup.
Permission is hereby granted, free of charge, to any person obtaining a copy of
this software and associated documentation files (the "Software"), to deal in
the Software without restriction, including without limitation the rights to
use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
the Software, and to permit persons to whom the Software is furnished to do so.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
'''
import os
import sys
# If we are running from the Python-LLFUSE source directory, try
# to load the module from there first.
basedir = os.path.abspath(os.path.join(os.path.dirname(sys.argv[0]), '..'))
if (os.path.exists(os.path.join(basedir, 'setup.py')) and
os.path.exists(os.path.join(basedir, 'src', 'llfuse.pyx'))):
sys.path.insert(0, os.path.join(basedir, 'src'))
from argparse import ArgumentParser
import stat
import logging
import errno
import llfuse
try:
import faulthandler
except ImportError:
pass
else:
faulthandler.enable()
log = logging.getLogger(__name__)
class TestFs(llfuse.Operations):
def __init__(self):
super().__init__()
self.hello_name = b"message"
self.hello_inode = llfuse.ROOT_INODE+1
self.hello_data = b"hello world\n"
def getattr(self, inode, ctx=None):
entry = llfuse.EntryAttributes()
if inode == llfuse.ROOT_INODE:
entry.st_mode = (stat.S_IFDIR | 0o755)
entry.st_size = 0
elif inode == self.hello_inode:
entry.st_mode = (stat.S_IFREG | 0o644)
entry.st_size = len(self.hello_data)
else:
raise llfuse.FUSEError(errno.ENOENT)
stamp = int(1438467123.985654 * 1e9)
entry.st_atime_ns = stamp
entry.st_ctime_ns = stamp
entry.st_mtime_ns = stamp
entry.st_gid = os.getgid()
entry.st_uid = os.getuid()
entry.st_ino = inode
return entry
def lookup(self, parent_inode, name, ctx=None):
if parent_inode != llfuse.ROOT_INODE or name != self.hello_name:
raise llfuse.FUSEError(errno.ENOENT)
return self.getattr(self.hello_inode)
def opendir(self, inode, ctx):
if inode != llfuse.ROOT_INODE:
raise llfuse.FUSEError(errno.ENOENT)
return inode
def readdir(self, fh, off):
assert fh == llfuse.ROOT_INODE
# only one entry
if off == 0:
yield (self.hello_name, self.getattr(self.hello_inode), 1)
def open(self, inode, flags, ctx):
if inode != self.hello_inode:
raise llfuse.FUSEError(errno.ENOENT)
if flags & os.O_RDWR or flags & os.O_WRONLY:
raise llfuse.FUSEError(errno.EACCES)
return inode
def read(self, fh, off, size):
assert fh == self.hello_inode
return self.hello_data[off:off+size]
def init_logging(debug=False):
formatter = logging.Formatter('%(asctime)s.%(msecs)03d %(threadName)s: '
'[%(name)s] %(message)s', datefmt="%Y-%m-%d %H:%M:%S")
handler = logging.StreamHandler()
handler.setFormatter(formatter)
root_logger = logging.getLogger()
if debug:
handler.setLevel(logging.DEBUG)
root_logger.setLevel(logging.DEBUG)
else:
handler.setLevel(logging.INFO)
root_logger.setLevel(logging.INFO)
root_logger.addHandler(handler)
def parse_args():
'''Parse command line'''
parser = ArgumentParser()
parser.add_argument('mountpoint', type=str,
help='Where to mount the file system')
parser.add_argument('--debug', action='store_true', default=False,
help='Enable debugging output')
parser.add_argument('--debug-fuse', action='store_true', default=False,
help='Enable FUSE debugging output')
return parser.parse_args()
def main():
options = parse_args()
init_logging(options.debug)
testfs = TestFs()
fuse_options = set(llfuse.default_options)
fuse_options.add('fsname=lltest')
if options.debug_fuse:
fuse_options.add('debug')
llfuse.init(testfs, options.mountpoint, fuse_options)
try:
llfuse.main(workers=1)
except:
llfuse.close(unmount=False)
raise
llfuse.close()
if __name__ == '__main__':
main()
|
In-memory File System¶
(shipped as examples/tmpfs.py)
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'''
tmpfs.py - Example file system for Python-LLFUSE.
This file system stores all data in memory. It is compatible with both Python
2.x and 3.x.
Copyright © 2013 Nikolaus Rath <Nikolaus.org>
Permission is hereby granted, free of charge, to any person obtaining a copy of
this software and associated documentation files (the "Software"), to deal in
the Software without restriction, including without limitation the rights to
use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
the Software, and to permit persons to whom the Software is furnished to do so.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
'''
import os
import sys
# If we are running from the Python-LLFUSE source directory, try
# to load the module from there first.
basedir = os.path.abspath(os.path.join(os.path.dirname(sys.argv[0]), '..'))
if (os.path.exists(os.path.join(basedir, 'setup.py')) and
os.path.exists(os.path.join(basedir, 'src', 'llfuse.pyx'))):
sys.path.insert(0, os.path.join(basedir, 'src'))
import llfuse
import errno
import stat
from time import time
import sqlite3
import logging
from collections import defaultdict
from llfuse import FUSEError
from argparse import ArgumentParser
try:
import faulthandler
except ImportError:
pass
else:
faulthandler.enable()
log = logging.getLogger()
class Operations(llfuse.Operations):
'''An example filesystem that stores all data in memory
This is a very simple implementation with terrible performance.
Don't try to store significant amounts of data. Also, there are
some other flaws that have not been fixed to keep the code easier
to understand:
* atime, mtime and ctime are not updated
* generation numbers are not supported
'''
def __init__(self):
super().__init__()
self.db = sqlite3.connect(':memory:')
self.db.text_factory = str
self.db.row_factory = sqlite3.Row
self.cursor = self.db.cursor()
self.inode_open_count = defaultdict(int)
self.init_tables()
def init_tables(self):
'''Initialize file system tables'''
self.cursor.execute("""
CREATE TABLE inodes (
id INTEGER PRIMARY KEY,
uid INT NOT NULL,
gid INT NOT NULL,
mode INT NOT NULL,
mtime_ns INT NOT NULL,
atime_ns INT NOT NULL,
ctime_ns INT NOT NULL,
target BLOB(256) ,
size INT NOT NULL DEFAULT 0,
rdev INT NOT NULL DEFAULT 0,
data BLOB
)
""")
self.cursor.execute("""
CREATE TABLE contents (
rowid INTEGER PRIMARY KEY AUTOINCREMENT,
name BLOB(256) NOT NULL,
inode INT NOT NULL REFERENCES inodes(id),
parent_inode INT NOT NULL REFERENCES inodes(id),
UNIQUE (name, parent_inode)
)""")
# Insert root directory
now_ns = int(time() * 1e9)
self.cursor.execute("INSERT INTO inodes (id,mode,uid,gid,mtime_ns,atime_ns,ctime_ns) "
"VALUES (?,?,?,?,?,?,?)",
(llfuse.ROOT_INODE, stat.S_IFDIR | stat.S_IRUSR | stat.S_IWUSR
| stat.S_IXUSR | stat.S_IRGRP | stat.S_IXGRP | stat.S_IROTH
| stat.S_IXOTH, os.getuid(), os.getgid(), now_ns, now_ns, now_ns))
self.cursor.execute("INSERT INTO contents (name, parent_inode, inode) VALUES (?,?,?)",
(b'..', llfuse.ROOT_INODE, llfuse.ROOT_INODE))
def get_row(self, *a, **kw):
self.cursor.execute(*a, **kw)
try:
row = next(self.cursor)
except StopIteration:
raise NoSuchRowError()
try:
next(self.cursor)
except StopIteration:
pass
else:
raise NoUniqueValueError()
return row
def lookup(self, inode_p, name, ctx=None):
if name == '.':
inode = inode_p
elif name == '..':
inode = self.get_row("SELECT * FROM contents WHERE inode=?",
(inode_p,))['parent_inode']
else:
try:
inode = self.get_row("SELECT * FROM contents WHERE name=? AND parent_inode=?",
(name, inode_p))['inode']
except NoSuchRowError:
raise(llfuse.FUSEError(errno.ENOENT))
return self.getattr(inode, ctx)
def getattr(self, inode, ctx=None):
row = self.get_row('SELECT * FROM inodes WHERE id=?', (inode,))
entry = llfuse.EntryAttributes()
entry.st_ino = inode
entry.generation = 0
entry.entry_timeout = 300
entry.attr_timeout = 300
entry.st_mode = row['mode']
entry.st_nlink = self.get_row("SELECT COUNT(inode) FROM contents WHERE inode=?",
(inode,))[0]
entry.st_uid = row['uid']
entry.st_gid = row['gid']
entry.st_rdev = row['rdev']
entry.st_size = row['size']
entry.st_blksize = 512
entry.st_blocks = 1
entry.st_atime_ns = row['atime_ns']
entry.st_mtime_ns = row['mtime_ns']
entry.st_ctime_ns = row['ctime_ns']
return entry
def readlink(self, inode, ctx):
return self.get_row('SELECT * FROM inodes WHERE id=?', (inode,))['target']
def opendir(self, inode, ctx):
return inode
def readdir(self, inode, off):
if off == 0:
off = -1
cursor2 = self.db.cursor()
cursor2.execute("SELECT * FROM contents WHERE parent_inode=? "
'AND rowid > ? ORDER BY rowid', (inode, off))
for row in cursor2:
yield (row['name'], self.getattr(row['inode']), row['rowid'])
def unlink(self, inode_p, name,ctx):
entry = self.lookup(inode_p, name)
if stat.S_ISDIR(entry.st_mode):
raise llfuse.FUSEError(errno.EISDIR)
self._remove(inode_p, name, entry)
def rmdir(self, inode_p, name, ctx):
entry = self.lookup(inode_p, name)
if not stat.S_ISDIR(entry.st_mode):
raise llfuse.FUSEError(errno.ENOTDIR)
self._remove(inode_p, name, entry)
def _remove(self, inode_p, name, entry):
if self.get_row("SELECT COUNT(inode) FROM contents WHERE parent_inode=?",
(entry.st_ino,))[0] > 0:
raise llfuse.FUSEError(errno.ENOTEMPTY)
self.cursor.execute("DELETE FROM contents WHERE name=? AND parent_inode=?",
(name, inode_p))
if entry.st_nlink == 1 and entry.st_ino not in self.inode_open_count:
self.cursor.execute("DELETE FROM inodes WHERE id=?", (entry.st_ino,))
def symlink(self, inode_p, name, target, ctx):
mode = (stat.S_IFLNK | stat.S_IRUSR | stat.S_IWUSR | stat.S_IXUSR |
stat.S_IRGRP | stat.S_IWGRP | stat.S_IXGRP |
stat.S_IROTH | stat.S_IWOTH | stat.S_IXOTH)
return self._create(inode_p, name, mode, ctx, target=target)
def rename(self, inode_p_old, name_old, inode_p_new, name_new, ctx):
entry_old = self.lookup(inode_p_old, name_old)
try:
entry_new = self.lookup(inode_p_new, name_new)
except llfuse.FUSEError as exc:
if exc.errno != errno.ENOENT:
raise
target_exists = False
else:
target_exists = True
if target_exists:
self._replace(inode_p_old, name_old, inode_p_new, name_new,
entry_old, entry_new)
else:
self.cursor.execute("UPDATE contents SET name=?, parent_inode=? WHERE name=? "
"AND parent_inode=?", (name_new, inode_p_new,
name_old, inode_p_old))
def _replace(self, inode_p_old, name_old, inode_p_new, name_new,
entry_old, entry_new):
if self.get_row("SELECT COUNT(inode) FROM contents WHERE parent_inode=?",
(entry_new.st_ino,))[0] > 0:
raise llfuse.FUSEError(errno.ENOTEMPTY)
self.cursor.execute("UPDATE contents SET inode=? WHERE name=? AND parent_inode=?",
(entry_old.st_ino, name_new, inode_p_new))
self.db.execute('DELETE FROM contents WHERE name=? AND parent_inode=?',
(name_old, inode_p_old))
if entry_new.st_nlink == 1 and entry_new.st_ino not in self.inode_open_count:
self.cursor.execute("DELETE FROM inodes WHERE id=?", (entry_new.st_ino,))
def link(self, inode, new_inode_p, new_name, ctx):
entry_p = self.getattr(new_inode_p)
if entry_p.st_nlink == 0:
log.warn('Attempted to create entry %s with unlinked parent %d',
new_name, new_inode_p)
raise FUSEError(errno.EINVAL)
self.cursor.execute("INSERT INTO contents (name, inode, parent_inode) VALUES(?,?,?)",
(new_name, inode, new_inode_p))
return self.getattr(inode)
def setattr(self, inode, attr, fields, fh, ctx):
if fields.update_size:
data = self.get_row('SELECT data FROM inodes WHERE id=?', (inode,))[0]
if data is None:
data = b''
if len(data) < attr.st_size:
data = data + b'\0' * (attr.st_size - len(data))
else:
data = data[:attr.st_size]
self.cursor.execute('UPDATE inodes SET data=?, size=? WHERE id=?',
(memoryview(data), attr.st_size, inode))
if fields.update_mode:
self.cursor.execute('UPDATE inodes SET mode=? WHERE id=?',
(attr.st_mode, inode))
if fields.update_uid:
self.cursor.execute('UPDATE inodes SET uid=? WHERE id=?',
(attr.st_uid, inode))
if fields.update_gid:
self.cursor.execute('UPDATE inodes SET gid=? WHERE id=?',
(attr.st_gid, inode))
if fields.update_atime:
self.cursor.execute('UPDATE inodes SET atime_ns=? WHERE id=?',
(attr.st_atime_ns, inode))
if fields.update_mtime:
self.cursor.execute('UPDATE inodes SET mtime_ns=? WHERE id=?',
(attr.st_mtime_ns, inode))
return self.getattr(inode)
def mknod(self, inode_p, name, mode, rdev, ctx):
return self._create(inode_p, name, mode, ctx, rdev=rdev)
def mkdir(self, inode_p, name, mode, ctx):
return self._create(inode_p, name, mode, ctx)
def statfs(self, ctx):
stat_ = llfuse.StatvfsData()
stat_.f_bsize = 512
stat_.f_frsize = 512
size = self.get_row('SELECT SUM(size) FROM inodes')[0]
stat_.f_blocks = size // stat_.f_frsize
stat_.f_bfree = max(size // stat_.f_frsize, 1024)
stat_.f_bavail = stat_.f_bfree
inodes = self.get_row('SELECT COUNT(id) FROM inodes')[0]
stat_.f_files = inodes
stat_.f_ffree = max(inodes , 100)
stat_.f_favail = stat_.f_ffree
return stat_
def open(self, inode, flags, ctx):
# Yeah, unused arguments
#pylint: disable=W0613
self.inode_open_count[inode] += 1
# Use inodes as a file handles
return inode
def access(self, inode, mode, ctx):
# Yeah, could be a function and has unused arguments
#pylint: disable=R0201,W0613
return True
def create(self, inode_parent, name, mode, flags, ctx):
#pylint: disable=W0612
entry = self._create(inode_parent, name, mode, ctx)
self.inode_open_count[entry.st_ino] += 1
return (entry.st_ino, entry)
def _create(self, inode_p, name, mode, ctx, rdev=0, target=None):
if self.getattr(inode_p).st_nlink == 0:
log.warn('Attempted to create entry %s with unlinked parent %d',
name, inode_p)
raise FUSEError(errno.EINVAL)
now_ns = int(time() * 1e9)
self.cursor.execute('INSERT INTO inodes (uid, gid, mode, mtime_ns, atime_ns, '
'ctime_ns, target, rdev) VALUES(?, ?, ?, ?, ?, ?, ?, ?)',
(ctx.uid, ctx.gid, mode, now_ns, now_ns, now_ns, target, rdev))
inode = self.cursor.lastrowid
self.db.execute("INSERT INTO contents(name, inode, parent_inode) VALUES(?,?,?)",
(name, inode, inode_p))
return self.getattr(inode)
def read(self, fh, offset, length):
data = self.get_row('SELECT data FROM inodes WHERE id=?', (fh,))[0]
if data is None:
data = b''
return data[offset:offset+length]
def write(self, fh, offset, buf):
data = self.get_row('SELECT data FROM inodes WHERE id=?', (fh,))[0]
if data is None:
data = b''
data = data[:offset] + buf + data[offset+len(buf):]
self.cursor.execute('UPDATE inodes SET data=?, size=? WHERE id=?',
(memoryview(data), len(data), fh))
return len(buf)
def release(self, fh):
self.inode_open_count[fh] -= 1
if self.inode_open_count[fh] == 0:
del self.inode_open_count[fh]
if self.getattr(fh).st_nlink == 0:
self.cursor.execute("DELETE FROM inodes WHERE id=?", (fh,))
class NoUniqueValueError(Exception):
def __str__(self):
return 'Query generated more than 1 result row'
class NoSuchRowError(Exception):
def __str__(self):
return 'Query produced 0 result rows'
def init_logging(debug=False):
formatter = logging.Formatter('%(asctime)s.%(msecs)03d %(threadName)s: '
'[%(name)s] %(message)s', datefmt="%Y-%m-%d %H:%M:%S")
handler = logging.StreamHandler()
handler.setFormatter(formatter)
root_logger = logging.getLogger()
if debug:
handler.setLevel(logging.DEBUG)
root_logger.setLevel(logging.DEBUG)
else:
handler.setLevel(logging.INFO)
root_logger.setLevel(logging.INFO)
root_logger.addHandler(handler)
def parse_args():
'''Parse command line'''
parser = ArgumentParser()
parser.add_argument('mountpoint', type=str,
help='Where to mount the file system')
parser.add_argument('--debug', action='store_true', default=False,
help='Enable debugging output')
parser.add_argument('--debug-fuse', action='store_true', default=False,
help='Enable FUSE debugging output')
return parser.parse_args()
if __name__ == '__main__':
options = parse_args()
init_logging(options.debug)
operations = Operations()
fuse_options = set(llfuse.default_options)
fuse_options.add('fsname=tmpfs')
fuse_options.discard('default_permissions')
if options.debug_fuse:
fuse_options.add('debug')
llfuse.init(operations, options.mountpoint, fuse_options)
# sqlite3 does not support multithreading
try:
llfuse.main(workers=1)
except:
llfuse.close(unmount=False)
raise
llfuse.close()
|
Passthrough / Overlay File System¶
(shipped as examples/passthroughfs.py)
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'''
passthroughfs.py - Example file system for Python-LLFUSE
This file system mirrors the contents of a specified directory tree. It requires
Python 3.3 (since Python 2.x does not support the follow_symlinks parameters for
os.* functions).
Caveats:
* Inode generation numbers are not passed through but set to zero.
* Block size (st_blksize) and number of allocated blocks (st_blocks) are not
passed through.
* Performance for large directories is not good, because the directory
is always read completely.
* There may be a way to break-out of the directory tree.
* The readdir implementation is not fully POSIX compliant. If a directory
contains hardlinks and is modified during a readdir call, readdir()
may return some of the hardlinked files twice or omit them completely.
* If you delete or rename files in the underlying file system, the
passthrough file system will get confused.
Copyright © Nikolaus Rath <Nikolaus.org>
Permission is hereby granted, free of charge, to any person obtaining a copy of
this software and associated documentation files (the "Software"), to deal in
the Software without restriction, including without limitation the rights to
use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
the Software, and to permit persons to whom the Software is furnished to do so.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
'''
import os
import sys
# If we are running from the Python-LLFUSE source directory, try
# to load the module from there first.
basedir = os.path.abspath(os.path.join(os.path.dirname(sys.argv[0]), '..'))
if (os.path.exists(os.path.join(basedir, 'setup.py')) and
os.path.exists(os.path.join(basedir, 'src', 'llfuse.pyx'))):
sys.path.insert(0, os.path.join(basedir, 'src'))
import llfuse
from argparse import ArgumentParser
import errno
import logging
import stat as stat_m
from llfuse import FUSEError
from os import fsencode, fsdecode
from collections import defaultdict
import faulthandler
faulthandler.enable()
log = logging.getLogger(__name__)
class Operations(llfuse.Operations):
def __init__(self, source):
super().__init__()
self._inode_path_map = { llfuse.ROOT_INODE: source }
self._lookup_cnt = defaultdict(lambda : 0)
self._fd_inode_map = dict()
self._inode_fd_map = dict()
self._fd_open_count = dict()
def _inode_to_path(self, inode):
try:
val = self._inode_path_map[inode]
except KeyError:
raise FUSEError(errno.ENOENT)
if isinstance(val, set):
# In case of hardlinks, pick any path
val = next(iter(val))
return val
def _add_path(self, inode, path):
log.debug('_add_path for %d, %s', inode, path)
self._lookup_cnt[inode] += 1
# With hardlinks, one inode may map to multiple paths.
if inode not in self._inode_path_map:
self._inode_path_map[inode] = path
return
val = self._inode_path_map[inode]
if isinstance(val, set):
val.add(path)
elif val != path:
self._inode_path_map[inode] = { path, val }
def forget(self, inode_list):
for (inode, nlookup) in inode_list:
if self._lookup_cnt[inode] > nlookup:
self._lookup_cnt[inode] -= nlookup
continue
log.debug('forgetting about inode %d', inode)
assert inode not in self._inode_fd_map
del self._lookup_cnt[inode]
try:
del self._inode_path_map[inode]
except KeyError: # may have been deleted
pass
def lookup(self, inode_p, name, ctx=None):
name = fsdecode(name)
log.debug('lookup for %s in %d', name, inode_p)
path = os.path.join(self._inode_to_path(inode_p), name)
attr = self._getattr(path=path)
if name != '.' and name != '..':
self._add_path(attr.st_ino, path)
return attr
def getattr(self, inode, ctx=None):
if inode in self._inode_fd_map:
return self._getattr(fd=self._inode_fd_map[inode])
else:
return self._getattr(path=self._inode_to_path(inode))
def _getattr(self, path=None, fd=None):
assert fd is None or path is None
assert not(fd is None and path is None)
try:
if fd is None:
stat = os.lstat(path)
else:
stat = os.fstat(fd)
except OSError as exc:
raise FUSEError(exc.errno)
entry = llfuse.EntryAttributes()
for attr in ('st_ino', 'st_mode', 'st_nlink', 'st_uid', 'st_gid',
'st_rdev', 'st_size', 'st_atime_ns', 'st_mtime_ns',
'st_ctime_ns'):
setattr(entry, attr, getattr(stat, attr))
entry.generation = 0
entry.entry_timeout = 5
entry.attr_timeout = 5
entry.st_blksize = 512
entry.st_blocks = ((entry.st_size+entry.st_blksize-1) // entry.st_blksize)
return entry
def readlink(self, inode, ctx):
path = self._inode_to_path(inode)
try:
target = os.readlink(path)
except OSError as exc:
raise FUSEError(exc.errno)
return fsencode(target)
def opendir(self, inode, ctx):
return inode
def readdir(self, inode, off):
path = self._inode_to_path(inode)
log.debug('reading %s', path)
entries = []
for name in os.listdir(path):
attr = self._getattr(path=os.path.join(path, name))
entries.append((attr.st_ino, name, attr))
log.debug('read %d entries, starting at %d', len(entries), off)
# This is not fully posix compatible. If there are hardlinks
# (two names with the same inode), we don't have a unique
# offset to start in between them. Note that we cannot simply
# count entries, because then we would skip over entries
# (or return them more than once) if the number of directory
# entries changes between two calls to readdir().
for (ino, name, attr) in sorted(entries):
if ino <= off:
continue
yield (fsencode(name), attr, ino)
def unlink(self, inode_p, name, ctx):
name = fsdecode(name)
parent = self._inode_to_path(inode_p)
path = os.path.join(parent, name)
try:
inode = os.lstat(path).st_ino
os.unlink(path)
except OSError as exc:
raise FUSEError(exc.errno)
if inode in self._lookup_cnt:
self._forget_path(inode, path)
def rmdir(self, inode_p, name, ctx):
name = fsdecode(name)
parent = self._inode_to_path(inode_p)
path = os.path.join(parent, name)
try:
inode = os.lstat(path).st_ino
os.rmdir(path)
except OSError as exc:
raise FUSEError(exc.errno)
if inode in self._lookup_cnt:
self._forget_path(inode, path)
def _forget_path(self, inode, path):
log.debug('forget %s for %d', path, inode)
val = self._inode_path_map[inode]
if isinstance(val, set):
val.remove(path)
if len(val) == 1:
self._inode_path_map[inode] = next(iter(val))
else:
del self._inode_path_map[inode]
def symlink(self, inode_p, name, target, ctx):
name = fsdecode(name)
target = fsdecode(target)
parent = self._inode_to_path(inode_p)
path = os.path.join(parent, name)
try:
os.symlink(target, path)
os.chown(path, ctx.uid, ctx.gid, follow_symlinks=False)
except OSError as exc:
raise FUSEError(exc.errno)
stat = os.lstat(path)
self._add_path(stat.st_ino, path)
return self.getattr(stat.st_ino)
def rename(self, inode_p_old, name_old, inode_p_new, name_new, ctx):
name_old = fsdecode(name_old)
name_new = fsdecode(name_new)
parent_old = self._inode_to_path(inode_p_old)
parent_new = self._inode_to_path(inode_p_new)
path_old = os.path.join(parent_old, name_old)
path_new = os.path.join(parent_new, name_new)
try:
os.rename(path_old, path_new)
inode = os.lstat(path_new).st_ino
except OSError as exc:
raise FUSEError(exc.errno)
if inode not in self._lookup_cnt:
return
val = self._inode_path_map[inode]
if isinstance(val, set):
assert len(val) > 1
val.add(path_new)
val.remove(path_old)
else:
assert val == path_old
self._inode_path_map[inode] = path_new
def link(self, inode, new_inode_p, new_name, ctx):
new_name = fsdecode(new_name)
parent = self._inode_to_path(new_inode_p)
path = os.path.join(parent, new_name)
try:
os.link(self._inode_to_path(inode), path, follow_symlinks=False)
except OSError as exc:
raise FUSEError(exc.errno)
self._add_path(inode, path)
return self.getattr(inode)
def setattr(self, inode, attr, fields, fh, ctx):
# We use the f* functions if possible so that we can handle
# a setattr() call for an inode without associated directory
# handle.
if fh is None:
path_or_fh = self._inode_to_path(inode)
truncate = os.truncate
chmod = os.chmod
chown = os.chown
stat = os.lstat
else:
path_or_fh = fh
truncate = os.ftruncate
chmod = os.fchmod
chown = os.fchown
stat = os.fstat
try:
if fields.update_size:
truncate(path_or_fh, attr.st_size)
if fields.update_mode:
# Under Linux, chmod always resolves symlinks so we should
# actually never get a setattr() request for a symbolic
# link.
assert not stat_m.S_ISLNK(attr.st_mode)
chmod(path_or_fh, stat_m.S_IMODE(attr.st_mode))
if fields.update_uid:
chown(path_or_fh, attr.st_uid, -1, follow_symlinks=False)
if fields.update_gid:
chown(path_or_fh, -1, attr.st_gid, follow_symlinks=False)
if fields.update_atime and fields.update_mtime:
# utime accepts both paths and file descriptiors
os.utime(path_or_fh, None, follow_symlinks=False,
ns=(attr.st_atime_ns, attr.st_mtime_ns))
elif fields.update_atime or fields.update_mtime:
# We can only set both values, so we first need to retrieve the
# one that we shouldn't be changing.
oldstat = stat(path_or_fh)
if not fields.update_atime:
attr.st_atime_ns = oldstat.st_atime_ns
else:
attr.st_mtime_ns = oldstat.st_mtime_ns
os.utime(path_or_fh, None, follow_symlinks=False,
ns=(attr.st_atime_ns, attr.st_mtime_ns))
except OSError as exc:
raise FUSEError(exc.errno)
return self.getattr(inode)
def mknod(self, inode_p, name, mode, rdev, ctx):
path = os.path.join(self._inode_to_path(inode_p), fsdecode(name))
try:
os.mknod(path, mode=(mode & ~ctx.umask), device=rdev)
os.chown(path, ctx.uid, ctx.gid)
except OSError as exc:
raise FUSEError(exc.errno)
attr = self._getattr(path=path)
self._add_path(attr.st_ino, path)
return attr
def mkdir(self, inode_p, name, mode, ctx):
path = os.path.join(self._inode_to_path(inode_p), fsdecode(name))
try:
os.mkdir(path, mode=(mode & ~ctx.umask))
os.chown(path, ctx.uid, ctx.gid)
except OSError as exc:
raise FUSEError(exc.errno)
attr = self._getattr(path=path)
self._add_path(attr.st_ino, path)
return attr
def statfs(self, ctx):
root = self._inode_path_map[llfuse.ROOT_INODE]
stat_ = llfuse.StatvfsData()
try:
statfs = os.statvfs(root)
except OSError as exc:
raise FUSEError(exc.errno)
for attr in ('f_bsize', 'f_frsize', 'f_blocks', 'f_bfree', 'f_bavail',
'f_files', 'f_ffree', 'f_favail'):
setattr(stat_, attr, getattr(statfs, attr))
stat_.f_namemax = statfs.f_namemax - (len(root)+1)
return stat_
def open(self, inode, flags, ctx):
if inode in self._inode_fd_map:
fd = self._inode_fd_map[inode]
self._fd_open_count[fd] += 1
return fd
assert flags & os.O_CREAT == 0
try:
fd = os.open(self._inode_to_path(inode), flags)
except OSError as exc:
raise FUSEError(exc.errno)
self._inode_fd_map[inode] = fd
self._fd_inode_map[fd] = inode
self._fd_open_count[fd] = 1
return fd
def create(self, inode_p, name, mode, flags, ctx):
path = os.path.join(self._inode_to_path(inode_p), fsdecode(name))
try:
fd = os.open(path, flags | os.O_CREAT | os.O_TRUNC)
except OSError as exc:
raise FUSEError(exc.errno)
attr = self._getattr(fd=fd)
self._add_path(attr.st_ino, path)
self._inode_fd_map[attr.st_ino] = fd
self._fd_inode_map[fd] = attr.st_ino
self._fd_open_count[fd] = 1
return (fd, attr)
def read(self, fd, offset, length):
os.lseek(fd, offset, os.SEEK_SET)
return os.read(fd, length)
def write(self, fd, offset, buf):
os.lseek(fd, offset, os.SEEK_SET)
return os.write(fd, buf)
def release(self, fd):
if self._fd_open_count[fd] > 1:
self._fd_open_count[fd] -= 1
return
del self._fd_open_count[fd]
inode = self._fd_inode_map[fd]
del self._inode_fd_map[inode]
del self._fd_inode_map[fd]
try:
os.close(fd)
except OSError as exc:
raise FUSEError(exc.errno)
def init_logging(debug=False):
formatter = logging.Formatter('%(asctime)s.%(msecs)03d %(threadName)s: '
'[%(name)s] %(message)s', datefmt="%Y-%m-%d %H:%M:%S")
handler = logging.StreamHandler()
handler.setFormatter(formatter)
root_logger = logging.getLogger()
if debug:
handler.setLevel(logging.DEBUG)
root_logger.setLevel(logging.DEBUG)
else:
handler.setLevel(logging.INFO)
root_logger.setLevel(logging.INFO)
root_logger.addHandler(handler)
def parse_args(args):
'''Parse command line'''
parser = ArgumentParser()
parser.add_argument('source', type=str,
help='Directory tree to mirror')
parser.add_argument('mountpoint', type=str,
help='Where to mount the file system')
parser.add_argument('--single', action='store_true', default=False,
help='Run single threaded')
parser.add_argument('--debug', action='store_true', default=False,
help='Enable debugging output')
parser.add_argument('--debug-fuse', action='store_true', default=False,
help='Enable FUSE debugging output')
return parser.parse_args(args)
def main():
options = parse_args(sys.argv[1:])
init_logging(options.debug)
operations = Operations(options.source)
log.debug('Mounting...')
fuse_options = set(llfuse.default_options)
fuse_options.add('fsname=passthroughfs')
if options.debug_fuse:
fuse_options.add('debug')
llfuse.init(operations, options.mountpoint, fuse_options)
try:
log.debug('Entering main loop..')
if options.single:
llfuse.main(workers=1)
else:
llfuse.main()
except:
llfuse.close(unmount=False)
raise
log.debug('Unmounting..')
llfuse.close()
if __name__ == '__main__':
main()
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