1 import errno, metadata, os, stat, struct, tempfile
4 from bup._helpers import UINT_MAX
5 from bup.helpers import (add_error, log, merge_iter, mmap_readwrite,
6 progress, qprogress, resolve_parent, slashappend)
11 INDEX_HDR = 'BUPI\0\0\0\6'
13 # Time values are handled as integer nanoseconds since the epoch in
14 # memory, but are written as xstat/metadata timespecs. This behavior
15 # matches the existing metadata/xstat/.bupm code.
17 # Record times (mtime, ctime, atime) as xstat/metadata timespecs, and
18 # store all of the times in the index so they won't interfere with the
19 # forthcoming metadata cache.
20 INDEX_SIG = '!QQQqQqQqQQII20sHIIQ'
22 ENTLEN = struct.calcsize(INDEX_SIG)
24 FOOTLEN = struct.calcsize(FOOTER_SIG)
26 IX_EXISTS = 0x8000 # file exists on filesystem
27 IX_HASHVALID = 0x4000 # the stored sha1 matches the filesystem
28 IX_SHAMISSING = 0x2000 # the stored sha1 object doesn't seem to exist
30 class Error(Exception):
34 class MetaStoreReader:
35 def __init__(self, filename):
37 self._file = open(filename, 'rb')
47 def metadata_at(self, ofs):
49 return metadata.Metadata.read(self._file)
52 class MetaStoreWriter:
53 # For now, we just append to the file, and try to handle any
54 # truncation or corruption somewhat sensibly.
56 def __init__(self, filename):
57 # Map metadata hashes to bupindex.meta offsets.
59 self._filename = filename
61 # FIXME: see how slow this is; does it matter?
62 m_file = open(filename, 'ab+')
67 m = metadata.Metadata.read(m_file)
69 m_encoded = m.encode()
70 self._offsets[m_encoded] = m_off
72 m = metadata.Metadata.read(m_file)
76 log('index metadata in %r appears to be corrupt' % filename)
80 self._file = open(filename, 'ab')
91 def store(self, metadata):
92 meta_encoded = metadata.encode(include_path=False)
93 ofs = self._offsets.get(meta_encoded)
96 ofs = self._file.tell()
97 self._file.write(meta_encoded)
98 self._offsets[meta_encoded] = ofs
103 def __init__(self, ename, parent):
110 (ofs,n) = (f.tell(), len(self.list))
112 count = len(self.list)
113 #log('popping %r with %d entries\n'
114 # % (''.join(self.ename), count))
118 self.parent.count += count + self.count
122 def _golevel(level, f, ename, newentry, metastore, tmax):
123 # close nodes back up the tree
125 default_meta_ofs = metastore.store(metadata.Metadata())
126 while ename[:len(level.ename)] != level.ename:
127 n = BlankNewEntry(level.ename[-1], default_meta_ofs, tmax)
129 (n.children_ofs,n.children_n) = level.write(f)
130 level.parent.list.append(n)
133 # create nodes down the tree
134 while len(level.ename) < len(ename):
135 level = Level(ename[:len(level.ename)+1], level)
137 # are we in precisely the right place?
138 assert(ename == level.ename)
140 BlankNewEntry(ename and level.ename[-1] or None, default_meta_ofs, tmax)
141 (n.children_ofs,n.children_n) = level.write(f)
143 level.parent.list.append(n)
150 def __init__(self, basename, name, meta_ofs, tmax):
151 self.basename = str(basename)
152 self.name = str(name)
153 self.meta_ofs = meta_ofs
155 self.children_ofs = 0
159 return ("(%s,0x%04x,%d,%d,%d,%d,%d,%d,%s/%s,0x%04x,%d,0x%08x/%d)"
160 % (self.name, self.dev, self.ino, self.nlink,
161 self.ctime, self.mtime, self.atime,
162 self.size, self.mode, self.gitmode,
163 self.flags, self.meta_ofs,
164 self.children_ofs, self.children_n))
168 ctime = xstat.nsecs_to_timespec(self.ctime)
169 mtime = xstat.nsecs_to_timespec(self.mtime)
170 atime = xstat.nsecs_to_timespec(self.atime)
171 return struct.pack(INDEX_SIG,
172 self.dev, self.ino, self.nlink,
176 self.size, self.mode,
177 self.gitmode, self.sha, self.flags,
178 self.children_ofs, self.children_n,
180 except (DeprecationWarning, struct.error) as e:
181 log('pack error: %s (%r)\n' % (e, self))
184 def from_stat(self, st, meta_ofs, tstart, check_device=True):
185 old = (self.dev if check_device else 0,
186 self.ino, self.nlink, self.ctime, self.mtime,
187 self.size, self.flags & IX_EXISTS)
188 new = (st.st_dev if check_device else 0,
189 st.st_ino, st.st_nlink, st.st_ctime, st.st_mtime,
190 st.st_size, IX_EXISTS)
193 self.nlink = st.st_nlink
194 self.ctime = st.st_ctime
195 self.mtime = st.st_mtime
196 self.atime = st.st_atime
197 self.size = st.st_size
198 self.mode = st.st_mode
199 self.flags |= IX_EXISTS
200 self.meta_ofs = meta_ofs
201 # Check that the ctime's "second" is at or after tstart's.
202 ctime_sec_in_ns = xstat.fstime_floor_secs(st.st_ctime) * 10**9
203 if ctime_sec_in_ns >= tstart or old != new \
204 or self.sha == EMPTY_SHA or not self.gitmode:
209 self.mtime = self._fixup_time(self.mtime)
210 self.ctime = self._fixup_time(self.ctime)
212 def _fixup_time(self, t):
213 if self.tmax != None and t > self.tmax:
219 f = IX_HASHVALID|IX_EXISTS
220 return (self.flags & f) == f
222 def invalidate(self):
223 self.flags &= ~IX_HASHVALID
225 def validate(self, gitmode, sha):
228 assert(gitmode+0 == gitmode)
229 self.gitmode = gitmode
231 self.flags |= IX_HASHVALID|IX_EXISTS
234 return not self.is_deleted()
236 def sha_missing(self):
237 return (self.flags & IX_SHAMISSING) or not (self.flags & IX_HASHVALID)
239 def is_deleted(self):
240 return (self.flags & IX_EXISTS) == 0
242 def set_deleted(self):
243 if self.flags & IX_EXISTS:
244 self.flags &= ~(IX_EXISTS | IX_HASHVALID)
247 return not self.is_fake()
250 return not self.ctime
253 return (cmp(b.name, a.name)
254 or cmp(a.is_valid(), b.is_valid())
255 or cmp(a.is_fake(), b.is_fake()))
258 f.write(self.basename + '\0' + self.packed())
261 class NewEntry(Entry):
262 def __init__(self, basename, name, tmax, dev, ino, nlink,
264 size, mode, gitmode, sha, flags, meta_ofs,
265 children_ofs, children_n):
266 Entry.__init__(self, basename, name, meta_ofs, tmax)
267 (self.dev, self.ino, self.nlink, self.ctime, self.mtime, self.atime,
268 self.size, self.mode, self.gitmode, self.sha,
269 self.flags, self.children_ofs, self.children_n
270 ) = (dev, ino, nlink, ctime, mtime, atime,
271 size, mode, gitmode, sha, flags, children_ofs, children_n)
275 class BlankNewEntry(NewEntry):
276 def __init__(self, basename, meta_ofs, tmax):
277 NewEntry.__init__(self, basename, basename, tmax,
278 0, 0, 0, 0, 0, 0, 0, 0,
279 0, EMPTY_SHA, 0, meta_ofs, 0, 0)
282 class ExistingEntry(Entry):
283 def __init__(self, parent, basename, name, m, ofs):
284 Entry.__init__(self, basename, name, None, None)
288 (self.dev, self.ino, self.nlink,
289 self.ctime, ctime_ns, self.mtime, mtime_ns, self.atime, atime_ns,
290 self.size, self.mode, self.gitmode, self.sha,
291 self.flags, self.children_ofs, self.children_n, self.meta_ofs
292 ) = struct.unpack(INDEX_SIG, str(buffer(m, ofs, ENTLEN)))
293 self.atime = xstat.timespec_to_nsecs((self.atime, atime_ns))
294 self.mtime = xstat.timespec_to_nsecs((self.mtime, mtime_ns))
295 self.ctime = xstat.timespec_to_nsecs((self.ctime, ctime_ns))
297 # effectively, we don't bother messing with IX_SHAMISSING if
298 # not IX_HASHVALID, since it's redundant, and repacking is more
299 # expensive than not repacking.
300 # This is implemented by having sha_missing() check IX_HASHVALID too.
301 def set_sha_missing(self, val):
303 oldval = self.sha_missing() and 1 or 0
305 flag = val and IX_SHAMISSING or 0
306 newflags = (self.flags & (~IX_SHAMISSING)) | flag
307 self.flags = newflags
310 def unset_sha_missing(self, flag):
311 if self.flags & IX_SHAMISSING:
312 self.flags &= ~IX_SHAMISSING
316 self._m[self._ofs:self._ofs+ENTLEN] = self.packed()
317 if self.parent and not self.is_valid():
318 self.parent.invalidate()
321 def iter(self, name=None, wantrecurse=None):
323 if dname and not dname.endswith('/'):
325 ofs = self.children_ofs
326 assert(ofs <= len(self._m))
327 assert(self.children_n <= UINT_MAX) # i.e. python struct 'I'
328 for i in xrange(self.children_n):
329 eon = self._m.find('\0', ofs)
333 basename = str(buffer(self._m, ofs, eon-ofs))
334 child = ExistingEntry(self, basename, self.name + basename,
337 or child.name.startswith(dname)
338 or child.name.endswith('/') and dname.startswith(child.name)):
339 if not wantrecurse or wantrecurse(child):
340 for e in child.iter(name=name, wantrecurse=wantrecurse):
342 if not name or child.name == name or child.name.startswith(dname):
344 ofs = eon + 1 + ENTLEN
351 def __init__(self, filename):
352 self.filename = filename
354 self.writable = False
358 f = open(filename, 'r+')
360 if e.errno == errno.ENOENT:
365 b = f.read(len(INDEX_HDR))
367 log('warning: %s: header: expected %r, got %r\n'
368 % (filename, INDEX_HDR, b))
370 st = os.fstat(f.fileno())
372 self.m = mmap_readwrite(f)
374 self.count = struct.unpack(FOOTER_SIG,
375 str(buffer(self.m, st.st_size-FOOTLEN, FOOTLEN)))[0]
381 return int(self.count)
383 def forward_iter(self):
385 while ofs+ENTLEN <= len(self.m)-FOOTLEN:
386 eon = self.m.find('\0', ofs)
390 basename = str(buffer(self.m, ofs, eon-ofs))
391 yield ExistingEntry(None, basename, basename, self.m, eon+1)
392 ofs = eon + 1 + ENTLEN
394 def iter(self, name=None, wantrecurse=None):
395 if len(self.m) > len(INDEX_HDR)+ENTLEN:
397 if dname and not dname.endswith('/'):
399 root = ExistingEntry(None, '/', '/',
400 self.m, len(self.m)-FOOTLEN-ENTLEN)
401 for sub in root.iter(name=name, wantrecurse=wantrecurse):
403 if not dname or dname == root.name:
409 def find(self, name):
410 return next((e for e in self.iter(name, wantrecurse=lambda x : True)
418 if self.writable and self.m:
423 if self.writable and self.m:
426 self.writable = False
428 def filter(self, prefixes, wantrecurse=None):
429 for (rp, path) in reduce_paths(prefixes):
431 for e in self.iter(rp, wantrecurse=wantrecurse):
433 assert(e.name.startswith(rp))
434 name = path + e.name[len(rp):]
437 # Always return at least the top for each prefix.
438 # Otherwise something like "save x/y" will produce
439 # nothing if x is up to date.
442 name = path + pe.name[len(rp):]
445 # FIXME: this function isn't very generic, because it splits the filename
446 # in an odd way and depends on a terminating '/' to indicate directories.
448 """Split a path into a list of elements of the file system hierarchy."""
450 l = [i+'/' for i in l[:-1]] + l[-1:]
452 l.pop() # extra blank caused by terminating '/'
457 def __init__(self, filename, metastore, tmax):
458 self.rootlevel = self.level = Level([], None)
463 self.filename = filename = resolve_parent(filename)
464 self.metastore = metastore
466 (dir,name) = os.path.split(filename)
467 (ffd,self.tmpname) = tempfile.mkstemp('.tmp', filename, dir)
468 self.f = os.fdopen(ffd, 'wb', 65536)
469 self.f.write(INDEX_HDR)
479 os.unlink(self.tmpname)
483 self.level = _golevel(self.level, self.f, [], None,
484 self.metastore, self.tmax)
485 self.count = self.rootlevel.count
488 self.f.write(struct.pack(FOOTER_SIG, self.count))
490 assert(self.level == None)
498 os.rename(self.tmpname, self.filename)
500 def _add(self, ename, entry):
501 if self.lastfile and self.lastfile <= ename:
502 raise Error('%r must come before %r'
503 % (''.join(ename), ''.join(self.lastfile)))
504 self.lastfile = ename
505 self.level = _golevel(self.level, self.f, ename, entry,
506 self.metastore, self.tmax)
508 def add(self, name, st, meta_ofs, hashgen = None):
509 endswith = name.endswith('/')
510 ename = pathsplit(name)
512 #log('add: %r %r\n' % (basename, name))
516 (gitmode, sha) = hashgen(name)
517 flags |= IX_HASHVALID
519 (gitmode, sha) = (0, EMPTY_SHA)
521 isdir = stat.S_ISDIR(st.st_mode)
522 assert(isdir == endswith)
523 e = NewEntry(basename, name, self.tmax,
524 st.st_dev, st.st_ino, st.st_nlink,
525 st.st_ctime, st.st_mtime, st.st_atime,
526 st.st_size, st.st_mode, gitmode, sha, flags,
530 meta_ofs = self.metastore.store(metadata.Metadata())
531 e = BlankNewEntry(basename, meta_ofs, self.tmax)
537 def add_ixentry(self, e):
538 e.children_ofs = e.children_n = 0
539 self._add(pathsplit(e.name), e)
541 def new_reader(self):
543 return Reader(self.tmpname)
546 def _slashappend_or_add_error(p, caller):
547 """Return p, after ensuring it has a single trailing slash if it names
548 a directory, unless there's an OSError, in which case, call
549 add_error() and return None."""
553 add_error('%s: %s' % (caller, e))
556 if stat.S_ISDIR(st.st_mode):
557 return slashappend(p)
561 def unique_resolved_paths(paths):
562 "Return a collection of unique resolved paths."
563 rps = (_slashappend_or_add_error(resolve_parent(p), 'unique_resolved_paths')
565 return frozenset((x for x in rps if x is not None))
568 def reduce_paths(paths):
571 rp = _slashappend_or_add_error(resolve_parent(p), 'reduce_paths')
573 xpaths.append((rp, slashappend(p) if rp.endswith('/') else p))
578 for (rp, p) in xpaths:
579 if prev and (prev == rp
580 or (prev.endswith('/') and rp.startswith(prev))):
581 continue # already superceded by previous path
582 paths.append((rp, p))
584 paths.sort(reverse=True)
589 def pfunc(count, total):
590 qprogress('bup: merging indexes (%d/%d)\r' % (count, total))
591 def pfinal(count, total):
592 progress('bup: merging indexes (%d/%d), done.\n' % (count, total))
593 return merge_iter(iters, 1024, pfunc, pfinal, key='name')