2 from __future__ import absolute_import, print_function
3 import errno, os, stat, struct, tempfile
5 from bup import metadata, xstat
6 from bup._helpers import UINT_MAX, bytescmp
7 from bup.compat import pending_raise, range
8 from bup.helpers import (add_error, log, merge_iter, mmap_readwrite,
9 progress, qprogress, resolve_parent, slashappend)
11 EMPTY_SHA = b'\0' * 20
12 FAKE_SHA = b'\x01' * 20
14 INDEX_HDR = b'BUPI\0\0\0\7'
16 # Time values are handled as integer nanoseconds since the epoch in
17 # memory, but are written as xstat/metadata timespecs. This behavior
18 # matches the existing metadata/xstat/.bupm code.
20 # Record times (mtime, ctime, atime) as xstat/metadata timespecs, and
21 # store all of the times in the index so they won't interfere with the
22 # forthcoming metadata cache.
27 'qQ' # ctime_s, ctime_ns
28 'qQ' # mtime_s, mtime_ns
29 'qQ' # atime_s, atime_ns
39 ENTLEN = struct.calcsize(INDEX_SIG)
41 FOOTLEN = struct.calcsize(FOOTER_SIG)
43 IX_EXISTS = 0x8000 # file exists on filesystem
44 IX_HASHVALID = 0x4000 # the stored sha1 matches the filesystem
45 IX_SHAMISSING = 0x2000 # the stored sha1 object doesn't seem to exist
47 class Error(Exception):
51 class MetaStoreReader:
52 def __init__(self, filename):
54 self._file = open(filename, 'rb')
57 f, self._file = self._file, None
67 def __exit__(self, type, value, traceback):
68 with pending_raise(value, rethrow=True):
71 def metadata_at(self, ofs):
73 return metadata.Metadata.read(self._file)
76 class MetaStoreWriter:
77 # For now, we just append to the file, and try to handle any
78 # truncation or corruption somewhat sensibly.
80 def __init__(self, filename):
82 # Map metadata hashes to bupindex.meta offsets.
84 self._filename = filename
86 # FIXME: see how slow this is; does it matter?
87 m_file = open(filename, 'ab+')
92 m = metadata.Metadata.read(m_file)
94 m_encoded = m.encode()
95 self._offsets[m_encoded] = m_off
97 m = metadata.Metadata.read(m_file)
101 log('index metadata in %r appears to be corrupt\n' % filename)
105 self._file = open(filename, 'ab')
119 def __exit__(self, type, value, traceback):
120 with pending_raise(value, rethrow=False):
123 def store(self, metadata):
124 meta_encoded = metadata.encode(include_path=False)
125 ofs = self._offsets.get(meta_encoded)
128 ofs = self._file.tell()
129 self._file.write(meta_encoded)
130 self._offsets[meta_encoded] = ofs
135 def __init__(self, ename, parent):
142 (ofs,n) = (f.tell(), len(self.list))
144 count = len(self.list)
145 #log('popping %r with %d entries\n'
146 # % (''.join(self.ename), count))
150 self.parent.count += count + self.count
154 def _golevel(level, f, ename, newentry, metastore, tmax):
155 # close nodes back up the tree
157 default_meta_ofs = metastore.store(metadata.Metadata())
158 while ename[:len(level.ename)] != level.ename:
159 n = BlankNewEntry(level.ename[-1], default_meta_ofs, tmax)
161 (n.children_ofs,n.children_n) = level.write(f)
162 level.parent.list.append(n)
165 # create nodes down the tree
166 while len(level.ename) < len(ename):
167 level = Level(ename[:len(level.ename)+1], level)
169 # are we in precisely the right place?
170 assert(ename == level.ename)
172 BlankNewEntry(ename and level.ename[-1] or None, default_meta_ofs, tmax)
173 (n.children_ofs,n.children_n) = level.write(f)
175 level.parent.list.append(n)
182 def __init__(self, basename, name, meta_ofs, tmax):
183 assert basename is None or isinstance(basename, bytes)
184 assert name is None or isinstance(name, bytes)
185 self.basename = basename
187 self.meta_ofs = meta_ofs
189 self.children_ofs = 0
193 return ("(%r,0x%04x,%d,%d,%d,%d,%d,%d,%s/%s,0x%04x,%d,0x%08x/%d)"
194 % (self.name, self.dev, self.ino, self.nlink,
195 self.ctime, self.mtime, self.atime,
196 self.size, self.mode, self.gitmode,
197 self.flags, self.meta_ofs,
198 self.children_ofs, self.children_n))
202 ctime = xstat.nsecs_to_timespec(self.ctime)
203 mtime = xstat.nsecs_to_timespec(self.mtime)
204 atime = xstat.nsecs_to_timespec(self.atime)
205 return struct.pack(INDEX_SIG,
206 self.dev, self.ino, self.nlink,
210 self.size, self.mode,
211 self.gitmode, self.sha, self.flags,
212 self.children_ofs, self.children_n,
214 except (DeprecationWarning, struct.error) as e:
215 log('pack error: %s (%r)\n' % (e, self))
218 def stale(self, st, check_device=True):
219 if self.size != st.st_size:
221 if self.mtime != st.st_mtime:
223 if self.sha == EMPTY_SHA:
227 if self.ctime != st.st_ctime:
229 if self.ino != st.st_ino:
231 if self.nlink != st.st_nlink:
233 if not (self.flags & IX_EXISTS):
235 if check_device and (self.dev != st.st_dev):
239 def update_from_stat(self, st, meta_ofs):
240 # Should only be called when the entry is stale(), and
241 # invalidate() should almost certainly be called afterward.
244 self.nlink = st.st_nlink
245 self.ctime = st.st_ctime
246 self.mtime = st.st_mtime
247 self.atime = st.st_atime
248 self.size = st.st_size
249 self.mode = st.st_mode
250 self.flags |= IX_EXISTS
251 self.meta_ofs = meta_ofs
255 self.mtime = self._fixup_time(self.mtime)
256 self.ctime = self._fixup_time(self.ctime)
258 def _fixup_time(self, t):
259 if self.tmax != None and t > self.tmax:
265 f = IX_HASHVALID|IX_EXISTS
266 return (self.flags & f) == f
268 def invalidate(self):
269 self.flags &= ~IX_HASHVALID
271 def validate(self, gitmode, sha):
274 assert(gitmode+0 == gitmode)
275 self.gitmode = gitmode
277 self.flags |= IX_HASHVALID|IX_EXISTS
280 return not self.is_deleted()
282 def sha_missing(self):
283 return (self.flags & IX_SHAMISSING) or not (self.flags & IX_HASHVALID)
285 def is_deleted(self):
286 return (self.flags & IX_EXISTS) == 0
288 def set_deleted(self):
289 if self.flags & IX_EXISTS:
290 self.flags &= ~(IX_EXISTS | IX_HASHVALID)
293 return not self.is_fake()
296 return not self.ctime
298 def _cmp(self, other):
299 # Note reversed name ordering
300 bc = bytescmp(other.name, self.name)
303 vc = self.is_valid() - other.is_valid()
306 fc = self.is_fake() - other.is_fake()
311 def __eq__(self, other):
312 return self._cmp(other) == 0
314 def __ne__(self, other):
315 return self._cmp(other) != 0
317 def __lt__(self, other):
318 return self._cmp(other) < 0
320 def __gt__(self, other):
321 return self._cmp(other) > 0
323 def __le__(self, other):
324 return self._cmp(other) <= 0
326 def __ge__(self, other):
327 return self._cmp(other) >= 0
330 f.write(self.basename + b'\0' + self.packed())
333 class NewEntry(Entry):
334 def __init__(self, basename, name, tmax, dev, ino, nlink,
336 size, mode, gitmode, sha, flags, meta_ofs,
337 children_ofs, children_n):
338 Entry.__init__(self, basename, name, meta_ofs, tmax)
339 (self.dev, self.ino, self.nlink, self.ctime, self.mtime, self.atime,
340 self.size, self.mode, self.gitmode, self.sha,
341 self.flags, self.children_ofs, self.children_n
342 ) = (dev, ino, nlink, ctime, mtime, atime,
343 size, mode, gitmode, sha, flags, children_ofs, children_n)
347 class BlankNewEntry(NewEntry):
348 def __init__(self, basename, meta_ofs, tmax):
349 NewEntry.__init__(self, basename, basename, tmax,
350 0, 0, 0, 0, 0, 0, 0, 0,
351 0, EMPTY_SHA, 0, meta_ofs, 0, 0)
354 class ExistingEntry(Entry):
355 def __init__(self, parent, basename, name, m, ofs):
356 Entry.__init__(self, basename, name, None, None)
360 (self.dev, self.ino, self.nlink,
361 self.ctime, ctime_ns, self.mtime, mtime_ns, self.atime, atime_ns,
362 self.size, self.mode, self.gitmode, self.sha,
363 self.flags, self.children_ofs, self.children_n, self.meta_ofs
364 ) = struct.unpack(INDEX_SIG, m[ofs : ofs + ENTLEN])
365 self.atime = xstat.timespec_to_nsecs((self.atime, atime_ns))
366 self.mtime = xstat.timespec_to_nsecs((self.mtime, mtime_ns))
367 self.ctime = xstat.timespec_to_nsecs((self.ctime, ctime_ns))
369 # effectively, we don't bother messing with IX_SHAMISSING if
370 # not IX_HASHVALID, since it's redundant, and repacking is more
371 # expensive than not repacking.
372 # This is implemented by having sha_missing() check IX_HASHVALID too.
373 def set_sha_missing(self, val):
375 oldval = self.sha_missing() and 1 or 0
377 flag = val and IX_SHAMISSING or 0
378 newflags = (self.flags & (~IX_SHAMISSING)) | flag
379 self.flags = newflags
382 def unset_sha_missing(self, flag):
383 if self.flags & IX_SHAMISSING:
384 self.flags &= ~IX_SHAMISSING
388 self._m[self._ofs:self._ofs+ENTLEN] = self.packed()
389 if self.parent and not self.is_valid():
390 self.parent.invalidate()
393 def iter(self, name=None, wantrecurse=None):
395 if dname and not dname.endswith(b'/'):
397 ofs = self.children_ofs
398 assert(ofs <= len(self._m))
399 assert(self.children_n <= UINT_MAX) # i.e. python struct 'I'
400 for i in range(self.children_n):
401 eon = self._m.find(b'\0', ofs)
405 basename = self._m[ofs : ofs + (eon - ofs)]
406 child = ExistingEntry(self, basename, self.name + basename,
409 or child.name.startswith(dname)
410 or child.name.endswith(b'/') and dname.startswith(child.name)):
411 if not wantrecurse or wantrecurse(child):
412 for e in child.iter(name=name, wantrecurse=wantrecurse):
414 if not name or child.name == name or child.name.startswith(dname):
416 ofs = eon + 1 + ENTLEN
423 def __init__(self, filename):
425 self.filename = filename
427 self.writable = False
431 f = open(filename, 'rb+')
433 if e.errno == errno.ENOENT:
438 b = f.read(len(INDEX_HDR))
440 log('warning: %s: header: expected %r, got %r\n'
441 % (filename, INDEX_HDR, b))
443 st = os.fstat(f.fileno())
445 self.m = mmap_readwrite(f)
447 self.count = struct.unpack(FOOTER_SIG,
448 self.m[st.st_size - FOOTLEN
454 def __exit__(self, type, value, traceback):
455 with pending_raise(value, rethrow=False):
459 return int(self.count)
461 def forward_iter(self):
463 while ofs+ENTLEN <= len(self.m)-FOOTLEN:
464 eon = self.m.find(b'\0', ofs)
468 basename = self.m[ofs : ofs + (eon - ofs)]
469 yield ExistingEntry(None, basename, basename, self.m, eon+1)
470 ofs = eon + 1 + ENTLEN
472 def iter(self, name=None, wantrecurse=None):
473 if len(self.m) > len(INDEX_HDR)+ENTLEN:
475 if dname and not dname.endswith(b'/'):
477 root = ExistingEntry(None, b'/', b'/',
478 self.m, len(self.m)-FOOTLEN-ENTLEN)
479 for sub in root.iter(name=name, wantrecurse=wantrecurse):
481 if not dname or dname == root.name:
487 def find(self, name):
488 return next((e for e in self.iter(name, wantrecurse=lambda x : True)
496 if self.writable and self.m:
502 if self.writable and self.m:
505 self.writable = False
510 def filter(self, prefixes, wantrecurse=None):
511 for (rp, path) in reduce_paths(prefixes):
513 for e in self.iter(rp, wantrecurse=wantrecurse):
515 assert(e.name.startswith(rp))
516 name = path + e.name[len(rp):]
519 # Always return at least the top for each prefix.
520 # Otherwise something like "save x/y" will produce
521 # nothing if x is up to date.
524 raise Exception("cannot find %r" % rp)
525 name = path + pe.name[len(rp):]
528 # FIXME: this function isn't very generic, because it splits the filename
529 # in an odd way and depends on a terminating '/' to indicate directories.
531 """Split a path into a list of elements of the file system hierarchy."""
533 l = [i + b'/' for i in l[:-1]] + l[-1:]
535 l.pop() # extra blank caused by terminating '/'
540 def __init__(self, filename, metastore, tmax):
542 self.rootlevel = self.level = Level([], None)
547 self.filename = filename = resolve_parent(filename)
548 self.metastore = metastore
550 (dir,name) = os.path.split(filename)
551 ffd, self.tmpname = tempfile.mkstemp(b'.tmp', filename, dir)
552 self.f = os.fdopen(ffd, 'wb', 65536)
553 self.f.write(INDEX_HDR)
558 def __exit__(self, type, value, traceback):
559 with pending_raise(value, rethrow=False):
568 os.unlink(self.tmpname)
572 self.level = _golevel(self.level, self.f, [], None,
573 self.metastore, self.tmax)
574 self.count = self.rootlevel.count
577 self.f.write(struct.pack(FOOTER_SIG, self.count))
579 assert(self.level == None)
588 os.rename(self.tmpname, self.filename)
593 def _add(self, ename, entry):
594 if self.lastfile and self.lastfile <= ename:
595 raise Error('%r must come before %r'
596 % (''.join(ename), ''.join(self.lastfile)))
597 self.lastfile = ename
598 self.level = _golevel(self.level, self.f, ename, entry,
599 self.metastore, self.tmax)
601 def add(self, name, st, meta_ofs, hashgen = None):
602 endswith = name.endswith(b'/')
603 ename = pathsplit(name)
605 #log('add: %r %r\n' % (basename, name))
609 (gitmode, sha) = hashgen(name)
610 flags |= IX_HASHVALID
612 (gitmode, sha) = (0, EMPTY_SHA)
614 isdir = stat.S_ISDIR(st.st_mode)
615 assert(isdir == endswith)
616 e = NewEntry(basename, name, self.tmax,
617 st.st_dev, st.st_ino, st.st_nlink,
618 st.st_ctime, st.st_mtime, st.st_atime,
619 st.st_size, st.st_mode, gitmode, sha, flags,
623 meta_ofs = self.metastore.store(metadata.Metadata())
624 e = BlankNewEntry(basename, meta_ofs, self.tmax)
630 def add_ixentry(self, e):
631 e.children_ofs = e.children_n = 0
632 self._add(pathsplit(e.name), e)
634 def new_reader(self):
636 return Reader(self.tmpname)
639 def _slashappend_or_add_error(p, caller):
640 """Return p, after ensuring it has a single trailing slash if it names
641 a directory, unless there's an OSError, in which case, call
642 add_error() and return None."""
646 add_error('%s: %s' % (caller, e))
649 if stat.S_ISDIR(st.st_mode):
650 return slashappend(p)
654 def unique_resolved_paths(paths):
655 "Return a collection of unique resolved paths."
656 rps = (_slashappend_or_add_error(resolve_parent(p), 'unique_resolved_paths')
658 return frozenset((x for x in rps if x is not None))
661 def reduce_paths(paths):
664 rp = _slashappend_or_add_error(resolve_parent(p), 'reduce_paths')
666 xpaths.append((rp, slashappend(p) if rp.endswith(b'/') else p))
671 for (rp, p) in xpaths:
672 if prev and (prev == rp
673 or (prev.endswith(b'/') and rp.startswith(prev))):
674 continue # already superceded by previous path
675 paths.append((rp, p))
677 paths.sort(reverse=True)
682 def pfunc(count, total):
683 qprogress('bup: merging indexes (%d/%d)\r' % (count, total))
684 def pfinal(count, total):
685 progress('bup: merging indexes (%d/%d), done.\n' % (count, total))
686 return merge_iter(iters, 1024, pfunc, pfinal, key='name')