1 """Git interaction library.
2 bup repositories are in Git format. This library allows us to
3 interact with the Git data structures.
6 from __future__ import absolute_import, print_function
7 import os, sys, zlib, subprocess, struct, stat, re, tempfile, glob
8 from array import array
9 from binascii import hexlify, unhexlify
10 from collections import namedtuple
11 from itertools import islice
13 from bup import _helpers, hashsplit, path, midx, bloom, xstat
14 from bup.compat import (buffer,
15 byte_int, bytes_from_byte, bytes_from_uint,
21 from bup.io import path_msg
22 from bup.helpers import (Sha1, add_error, chunkyreader, debug1, debug2,
29 mmap_read, mmap_readwrite,
30 progress, qprogress, stat_if_exists,
36 repodir = None # The default repository, once initialized
38 _typemap = {b'blob': 3, b'tree': 2, b'commit': 1, b'tag': 4}
39 _typermap = {v: k for k, v in items(_typemap)}
46 class GitError(Exception):
50 def _gitenv(repo_dir=None):
53 return merge_dict(environ, {b'GIT_DIR': os.path.abspath(repo_dir)})
55 def _git_wait(cmd, p):
58 raise GitError('%r returned %d' % (cmd, rv))
60 def _git_exo(cmd, **kwargs):
61 kwargs['check'] = False
62 result = exo(cmd, **kwargs)
64 if proc.returncode != 0:
65 raise GitError('%r returned %d' % (cmd, proc.returncode))
68 def git_config_get(option, repo_dir=None, opttype=None, cfg_file=None):
69 assert not (repo_dir and cfg_file), "repo_dir and cfg_file cannot both be used"
70 cmd = [b'git', b'config', b'--null']
72 cmd.extend([b'--file', cfg_file])
74 cmd.extend([b'--int'])
75 elif opttype == 'bool':
76 cmd.extend([b'--bool'])
78 assert opttype is None
79 cmd.extend([b'--get', option])
82 env = _gitenv(repo_dir=repo_dir)
83 p = subprocess.Popen(cmd, stdout=subprocess.PIPE, env=env,
85 # with --null, git writes out a trailing \0 after the value
86 r = p.stdout.read()[:-1]
91 elif opttype == 'bool':
92 # git converts to 'true' or 'false'
96 raise GitError('%r returned %d' % (cmd, rc))
100 def parse_tz_offset(s):
101 """UTC offset in seconds."""
102 tz_off = (int(s[1:3]) * 60 * 60) + (int(s[3:5]) * 60)
103 if bytes_from_byte(s[0]) == b'-':
107 def parse_commit_gpgsig(sig):
108 """Return the original signature bytes.
110 i.e. with the "gpgsig " header and the leading space character on
111 each continuation line removed.
116 assert sig.startswith(b'gpgsig ')
118 return sig.replace(b'\n ', b'\n')
120 # FIXME: derived from http://git.rsbx.net/Documents/Git_Data_Formats.txt
121 # Make sure that's authoritative.
124 # https://github.com/git/git/blob/master/Documentation/technical/signature-format.txt
125 # The continuation lines have only one leading space.
127 _start_end_char = br'[^ .,:;<>"\'\0\n]'
128 _content_char = br'[^\0\n<>]'
129 _safe_str_rx = br'(?:%s{1,2}|(?:%s%s*%s))' \
131 _start_end_char, _content_char, _start_end_char)
132 _tz_rx = br'[-+]\d\d[0-5]\d'
133 _parent_rx = br'(?:parent [abcdefABCDEF0123456789]{40}\n)'
134 # Assumes every following line starting with a space is part of the
135 # mergetag. Is there a formal commit blob spec?
136 _mergetag_rx = br'(?:\nmergetag object [abcdefABCDEF0123456789]{40}(?:\n [^\0\n]*)*)'
137 _commit_rx = re.compile(br'''tree (?P<tree>[abcdefABCDEF0123456789]{40})
138 (?P<parents>%s*)author (?P<author_name>%s) <(?P<author_mail>%s)> (?P<asec>\d+) (?P<atz>%s)
139 committer (?P<committer_name>%s) <(?P<committer_mail>%s)> (?P<csec>\d+) (?P<ctz>%s)(?P<mergetag>%s?)
140 (?P<gpgsig>gpgsig .*\n(?: .*\n)*)?
141 (?P<message>(?:.|\n)*)''' % (_parent_rx,
142 _safe_str_rx, _safe_str_rx, _tz_rx,
143 _safe_str_rx, _safe_str_rx, _tz_rx,
145 _parent_hash_rx = re.compile(br'\s*parent ([abcdefABCDEF0123456789]{40})\s*')
147 # Note that the author_sec and committer_sec values are (UTC) epoch
148 # seconds, and for now the mergetag is not included.
149 CommitInfo = namedtuple('CommitInfo', ['tree', 'parents',
150 'author_name', 'author_mail',
151 'author_sec', 'author_offset',
152 'committer_name', 'committer_mail',
153 'committer_sec', 'committer_offset',
157 def parse_commit(content):
158 commit_match = re.match(_commit_rx, content)
160 raise Exception('cannot parse commit %r' % content)
161 matches = commit_match.groupdict()
162 return CommitInfo(tree=matches['tree'],
163 parents=re.findall(_parent_hash_rx, matches['parents']),
164 author_name=matches['author_name'],
165 author_mail=matches['author_mail'],
166 author_sec=int(matches['asec']),
167 author_offset=parse_tz_offset(matches['atz']),
168 committer_name=matches['committer_name'],
169 committer_mail=matches['committer_mail'],
170 committer_sec=int(matches['csec']),
171 committer_offset=parse_tz_offset(matches['ctz']),
172 gpgsig=parse_commit_gpgsig(matches['gpgsig']),
173 message=matches['message'])
176 def get_cat_data(cat_iterator, expected_type):
177 _, kind, _ = next(cat_iterator)
178 if kind != expected_type:
179 raise Exception('expected %r, saw %r' % (expected_type, kind))
180 return b''.join(cat_iterator)
182 def get_commit_items(id, cp):
183 return parse_commit(get_cat_data(cp.get(id), b'commit'))
185 def _local_git_date_str(epoch_sec):
186 return b'%d %s' % (epoch_sec, utc_offset_str(epoch_sec))
189 def _git_date_str(epoch_sec, tz_offset_sec):
190 offs = tz_offset_sec // 60
191 return b'%d %s%02d%02d' \
193 b'+' if offs >= 0 else b'-',
198 def repo(sub = b'', repo_dir=None):
199 """Get the path to the git repository or one of its subdirectories."""
200 repo_dir = repo_dir or repodir
202 raise GitError('You should call check_repo_or_die()')
204 # If there's a .git subdirectory, then the actual repo is in there.
205 gd = os.path.join(repo_dir, b'.git')
206 if os.path.exists(gd):
209 return os.path.join(repo_dir, sub)
213 re.compile(br'([^0-9a-z]|\b)([0-9a-z]{7})[0-9a-z]{33}([^0-9a-z]|\b)')
216 return _shorten_hash_rx.sub(br'\1\2*\3', s)
220 full = os.path.abspath(path)
221 fullrepo = os.path.abspath(repo(b''))
222 if not fullrepo.endswith(b'/'):
224 if full.startswith(fullrepo):
225 path = full[len(fullrepo):]
226 if path.startswith(b'index-cache/'):
227 path = path[len(b'index-cache/'):]
228 return shorten_hash(path)
231 def auto_midx(objdir):
232 args = [path.exe(), b'midx', b'--auto', b'--dir', objdir]
234 rv = subprocess.call(args, stdout=open(os.devnull, 'w'))
236 # make sure 'args' gets printed to help with debugging
237 add_error('%r: exception: %s' % (args, e))
240 add_error('%r: returned %d' % (args, rv))
242 args = [path.exe(), b'bloom', b'--dir', objdir]
244 rv = subprocess.call(args, stdout=open(os.devnull, 'w'))
246 # make sure 'args' gets printed to help with debugging
247 add_error('%r: exception: %s' % (args, e))
250 add_error('%r: returned %d' % (args, rv))
253 def mangle_name(name, mode, gitmode):
254 """Mangle a file name to present an abstract name for segmented files.
255 Mangled file names will have the ".bup" extension added to them. If a
256 file's name already ends with ".bup", a ".bupl" extension is added to
257 disambiguate normal files from segmented ones.
259 if stat.S_ISREG(mode) and not stat.S_ISREG(gitmode):
260 assert(stat.S_ISDIR(gitmode))
261 return name + b'.bup'
262 elif name.endswith(b'.bup') or name[:-1].endswith(b'.bup'):
263 return name + b'.bupl'
268 (BUP_NORMAL, BUP_CHUNKED) = (0,1)
269 def demangle_name(name, mode):
270 """Remove name mangling from a file name, if necessary.
272 The return value is a tuple (demangled_filename,mode), where mode is one of
275 * BUP_NORMAL : files that should be read as-is from the repository
276 * BUP_CHUNKED : files that were chunked and need to be reassembled
278 For more information on the name mangling algorithm, see mangle_name()
280 if name.endswith(b'.bupl'):
281 return (name[:-5], BUP_NORMAL)
282 elif name.endswith(b'.bup'):
283 return (name[:-4], BUP_CHUNKED)
284 elif name.endswith(b'.bupm'):
286 BUP_CHUNKED if stat.S_ISDIR(mode) else BUP_NORMAL)
287 return (name, BUP_NORMAL)
290 def calc_hash(type, content):
291 """Calculate some content's hash in the Git fashion."""
292 header = b'%s %d\0' % (type, len(content))
298 def shalist_item_sort_key(ent):
299 (mode, name, id) = ent
300 assert(mode+0 == mode)
301 if stat.S_ISDIR(mode):
307 def tree_encode(shalist):
308 """Generate a git tree object from (mode,name,hash) tuples."""
309 shalist = sorted(shalist, key = shalist_item_sort_key)
311 for (mode,name,bin) in shalist:
313 assert(mode+0 == mode)
315 assert(len(bin) == 20)
316 s = b'%o %s\0%s' % (mode,name,bin)
317 assert s[0] != b'0' # 0-padded octal is not acceptable in a git tree
322 def tree_decode(buf):
323 """Generate a list of (mode,name,hash) from the git tree object in buf."""
325 while ofs < len(buf):
326 z = buf.find(b'\0', ofs)
328 spl = buf[ofs:z].split(b' ', 1)
329 assert(len(spl) == 2)
331 sha = buf[z+1:z+1+20]
333 yield (int(mode, 8), name, sha)
336 def _encode_packobj(type, content, compression_level=1):
337 if compression_level not in (0, 1, 2, 3, 4, 5, 6, 7, 8, 9):
338 raise ValueError('invalid compression level %s' % compression_level)
341 szbits = (sz & 0x0f) | (_typemap[type]<<4)
344 if sz: szbits |= 0x80
345 szout += bytes_from_uint(szbits)
350 z = zlib.compressobj(compression_level)
352 yield z.compress(content)
356 def _decode_packobj(buf):
359 type = _typermap[(c & 0x70) >> 4]
366 sz |= (c & 0x7f) << shift
370 return (type, zlib.decompress(buf[i+1:]))
377 def find_offset(self, hash):
378 """Get the offset of an object inside the index file."""
379 idx = self._idx_from_hash(hash)
381 return self._ofs_from_idx(idx)
384 def exists(self, hash, want_source=False):
385 """Return nonempty if the object exists in this index."""
386 if hash and (self._idx_from_hash(hash) != None):
387 return want_source and os.path.basename(self.name) or True
390 def _idx_from_hash(self, hash):
391 global _total_searches, _total_steps
393 assert(len(hash) == 20)
394 b1 = byte_int(hash[0])
395 start = self.fanout[b1-1] # range -1..254
396 end = self.fanout[b1] # range 0..255
398 _total_steps += 1 # lookup table is a step
401 mid = start + (end - start) // 2
402 v = self._idx_to_hash(mid)
412 class PackIdxV1(PackIdx):
413 """Object representation of a Git pack index (version 1) file."""
414 def __init__(self, filename, f):
416 self.idxnames = [self.name]
417 self.map = mmap_read(f)
418 # Min size for 'L' is 4, which is sufficient for struct's '!I'
419 self.fanout = array('L', struct.unpack('!256I', self.map))
420 self.fanout.append(0) # entry "-1"
421 self.nsha = self.fanout[255]
422 self.sha_ofs = 256 * 4
423 # Avoid slicing shatable for individual hashes (very high overhead)
424 self.shatable = buffer(self.map, self.sha_ofs, self.nsha * 24)
429 def __exit__(self, type, value, traceback):
430 with pending_raise(value, rethrow=False):
434 return int(self.nsha) # int() from long for python 2
436 def _ofs_from_idx(self, idx):
437 if idx >= self.nsha or idx < 0:
438 raise IndexError('invalid pack index index %d' % idx)
439 ofs = self.sha_ofs + idx * 24
440 return struct.unpack_from('!I', self.map, offset=ofs)[0]
442 def _idx_to_hash(self, idx):
443 if idx >= self.nsha or idx < 0:
444 raise IndexError('invalid pack index index %d' % idx)
445 ofs = self.sha_ofs + idx * 24 + 4
446 return self.map[ofs : ofs + 20]
449 start = self.sha_ofs + 4
450 for ofs in range(start, start + 24 * self.nsha, 24):
451 yield self.map[ofs : ofs + 20]
454 if self.map is not None:
460 class PackIdxV2(PackIdx):
461 """Object representation of a Git pack index (version 2) file."""
462 def __init__(self, filename, f):
464 self.idxnames = [self.name]
465 self.map = mmap_read(f)
466 assert self.map[0:8] == b'\377tOc\0\0\0\2'
467 # Min size for 'L' is 4, which is sufficient for struct's '!I'
468 self.fanout = array('L', struct.unpack_from('!256I', self.map, offset=8))
469 self.fanout.append(0)
470 self.nsha = self.fanout[255]
471 self.sha_ofs = 8 + 256*4
472 self.ofstable_ofs = self.sha_ofs + self.nsha * 20 + self.nsha * 4
473 self.ofs64table_ofs = self.ofstable_ofs + self.nsha * 4
474 # Avoid slicing this for individual hashes (very high overhead)
475 self.shatable = buffer(self.map, self.sha_ofs, self.nsha*20)
480 def __exit__(self, type, value, traceback):
481 with pending_raise(value, rethrow=False):
485 return int(self.nsha) # int() from long for python 2
487 def _ofs_from_idx(self, idx):
488 if idx >= self.nsha or idx < 0:
489 raise IndexError('invalid pack index index %d' % idx)
490 ofs_ofs = self.ofstable_ofs + idx * 4
491 ofs = struct.unpack_from('!I', self.map, offset=ofs_ofs)[0]
493 idx64 = ofs & 0x7fffffff
494 ofs64_ofs = self.ofs64table_ofs + idx64 * 8
495 ofs = struct.unpack_from('!Q', self.map, offset=ofs64_ofs)[0]
498 def _idx_to_hash(self, idx):
499 if idx >= self.nsha or idx < 0:
500 raise IndexError('invalid pack index index %d' % idx)
501 ofs = self.sha_ofs + idx * 20
502 return self.map[ofs : ofs + 20]
506 for ofs in range(start, start + 20 * self.nsha, 20):
507 yield self.map[ofs : ofs + 20]
510 if self.map is not None:
518 def __init__(self, dir, ignore_midx=False):
520 assert(_mpi_count == 0) # these things suck tons of VM; don't waste it
525 self.do_bloom = False
527 self.ignore_midx = ignore_midx
533 assert(_mpi_count == 0)
536 return iter(idxmerge(self.packs))
539 return sum(len(pack) for pack in self.packs)
541 def exists(self, hash, want_source=False):
542 """Return nonempty if the object exists in the index files."""
543 global _total_searches
545 if hash in self.also:
547 if self.do_bloom and self.bloom:
548 if self.bloom.exists(hash):
549 self.do_bloom = False
551 _total_searches -= 1 # was counted by bloom
553 for i in range(len(self.packs)):
555 _total_searches -= 1 # will be incremented by sub-pack
556 ix = p.exists(hash, want_source=want_source)
558 # reorder so most recently used packs are searched first
559 self.packs = [p] + self.packs[:i] + self.packs[i+1:]
564 def refresh(self, skip_midx = False):
565 """Refresh the index list.
566 This method verifies if .midx files were superseded (e.g. all of its
567 contents are in another, bigger .midx file) and removes the superseded
570 If skip_midx is True, all work on .midx files will be skipped and .midx
571 files will be removed from the list.
573 The instance variable 'ignore_midx' can force this function to
574 always act as if skip_midx was True.
576 if self.bloom is not None:
578 self.bloom = None # Always reopen the bloom as it may have been relaced
579 self.do_bloom = False
580 skip_midx = skip_midx or self.ignore_midx
581 d = dict((p.name, p) for p in self.packs
582 if not skip_midx or not isinstance(p, midx.PackMidx))
583 if os.path.exists(self.dir):
586 midxes = set(glob.glob(os.path.join(self.dir, b'*.midx')))
587 # remove any *.midx files from our list that no longer exist
588 for ix in list(d.values()):
589 if not isinstance(ix, midx.PackMidx):
591 if ix.name in midxes:
596 self.packs.remove(ix)
597 for ix in self.packs:
598 if isinstance(ix, midx.PackMidx):
599 for name in ix.idxnames:
600 d[os.path.join(self.dir, name)] = ix
603 mx = midx.PackMidx(full)
604 (mxd, mxf) = os.path.split(mx.name)
606 for n in mx.idxnames:
607 if not os.path.exists(os.path.join(mxd, n)):
608 log(('warning: index %s missing\n'
610 % (path_msg(n), path_msg(mxf)))
618 midxl.sort(key=lambda ix:
619 (-len(ix), -xstat.stat(ix.name).st_mtime))
622 for sub in ix.idxnames:
623 found = d.get(os.path.join(self.dir, sub))
624 if not found or isinstance(found, PackIdx):
625 # doesn't exist, or exists but not in a midx
630 for name in ix.idxnames:
631 d[os.path.join(self.dir, name)] = ix
632 elif not ix.force_keep:
633 debug1('midx: removing redundant: %s\n'
634 % path_msg(os.path.basename(ix.name)))
637 for full in glob.glob(os.path.join(self.dir, b'*.idx')):
641 except GitError as e:
645 bfull = os.path.join(self.dir, b'bup.bloom')
646 if self.bloom is None and os.path.exists(bfull):
647 self.bloom = bloom.ShaBloom(bfull)
648 self.packs = list(set(d.values()))
649 self.packs.sort(reverse=True, key=lambda x: len(x))
650 if self.bloom and self.bloom.valid() and len(self.bloom) >= len(self):
654 debug1('PackIdxList: using %d index%s.\n'
655 % (len(self.packs), len(self.packs)!=1 and 'es' or ''))
658 """Insert an additional object in the list."""
662 def open_idx(filename):
663 if filename.endswith(b'.idx'):
664 f = open(filename, 'rb')
666 if header[0:4] == b'\377tOc':
667 version = struct.unpack('!I', header[4:8])[0]
669 return PackIdxV2(filename, f)
671 raise GitError('%s: expected idx file version 2, got %d'
672 % (path_msg(filename), version))
673 elif len(header) == 8 and header[0:4] < b'\377tOc':
674 return PackIdxV1(filename, f)
676 raise GitError('%s: unrecognized idx file header'
677 % path_msg(filename))
678 elif filename.endswith(b'.midx'):
679 return midx.PackMidx(filename)
681 raise GitError('idx filenames must end with .idx or .midx')
684 def idxmerge(idxlist, final_progress=True):
685 """Generate a list of all the objects reachable in a PackIdxList."""
686 def pfunc(count, total):
687 qprogress('Reading indexes: %.2f%% (%d/%d)\r'
688 % (count*100.0/total, count, total))
689 def pfinal(count, total):
691 progress('Reading indexes: %.2f%% (%d/%d), done.\n'
692 % (100, total, total))
693 return merge_iter(idxlist, 10024, pfunc, pfinal)
696 def create_commit_blob(tree, parent,
697 author, adate_sec, adate_tz,
698 committer, cdate_sec, cdate_tz,
700 if adate_tz is not None:
701 adate_str = _git_date_str(adate_sec, adate_tz)
703 adate_str = _local_git_date_str(adate_sec)
704 if cdate_tz is not None:
705 cdate_str = _git_date_str(cdate_sec, cdate_tz)
707 cdate_str = _local_git_date_str(cdate_sec)
709 if tree: l.append(b'tree %s' % hexlify(tree))
710 if parent: l.append(b'parent %s' % hexlify(parent))
711 if author: l.append(b'author %s %s' % (author, adate_str))
712 if committer: l.append(b'committer %s %s' % (committer, cdate_str))
718 def _make_objcache():
719 return PackIdxList(repo(b'objects/pack'))
721 # bup-gc assumes that it can disable all PackWriter activities
722 # (bloom/midx/cache) via the constructor and close() arguments.
725 """Writes Git objects inside a pack file."""
726 def __init__(self, objcache_maker=_make_objcache, compression_level=1,
727 run_midx=True, on_pack_finish=None,
728 max_pack_size=None, max_pack_objects=None, repo_dir=None):
729 self.repo_dir = repo_dir or repo()
736 self.objcache_maker = objcache_maker
738 self.compression_level = compression_level
739 self.run_midx=run_midx
740 self.on_pack_finish = on_pack_finish
741 if not max_pack_size:
742 max_pack_size = git_config_get(b'pack.packSizeLimit',
743 repo_dir=self.repo_dir,
745 if not max_pack_size:
746 # larger packs slow down pruning
747 max_pack_size = 1000 * 1000 * 1000
748 self.max_pack_size = max_pack_size
749 # cache memory usage is about 83 bytes per object
750 self.max_pack_objects = max_pack_objects if max_pack_objects \
751 else max(1, self.max_pack_size // 5000)
756 def __exit__(self, type, value, traceback):
757 with pending_raise(value, rethrow=False):
762 objdir = dir = os.path.join(self.repo_dir, b'objects')
763 fd, name = tempfile.mkstemp(suffix=b'.pack', dir=objdir)
765 self.file = os.fdopen(fd, 'w+b')
770 self.parentfd = os.open(objdir, os.O_RDONLY)
776 assert name.endswith(b'.pack')
777 self.filename = name[:-5]
778 self.file.write(b'PACK\0\0\0\2\0\0\0\0')
779 self.idx = PackIdxV2Writer()
781 def _raw_write(self, datalist, sha):
784 # in case we get interrupted (eg. KeyboardInterrupt), it's best if
785 # the file never has a *partial* blob. So let's make sure it's
786 # all-or-nothing. (The blob shouldn't be very big anyway, thanks
787 # to our hashsplit algorithm.) f.write() does its own buffering,
788 # but that's okay because we'll flush it in _end().
789 oneblob = b''.join(datalist)
795 crc = zlib.crc32(oneblob) & 0xffffffff
796 self._update_idx(sha, crc, nw)
801 def _update_idx(self, sha, crc, size):
804 self.idx.add(sha, crc, self.file.tell() - size)
806 def _write(self, sha, type, content):
810 sha = calc_hash(type, content)
811 size, crc = self._raw_write(_encode_packobj(type, content,
812 self.compression_level),
814 if self.outbytes >= self.max_pack_size \
815 or self.count >= self.max_pack_objects:
819 def _require_objcache(self):
820 if self.objcache is None and self.objcache_maker:
821 self.objcache = self.objcache_maker()
822 if self.objcache is None:
824 "PackWriter not opened or can't check exists w/o objcache")
826 def exists(self, id, want_source=False):
827 """Return non-empty if an object is found in the object cache."""
828 self._require_objcache()
829 return self.objcache.exists(id, want_source=want_source)
831 def just_write(self, sha, type, content):
832 """Write an object to the pack file without checking for duplication."""
833 self._write(sha, type, content)
834 # If nothing else, gc doesn't have/want an objcache
835 if self.objcache is not None:
836 self.objcache.add(sha)
838 def maybe_write(self, type, content):
839 """Write an object to the pack file if not present and return its id."""
840 sha = calc_hash(type, content)
841 if not self.exists(sha):
842 self._require_objcache()
843 self.just_write(sha, type, content)
846 def new_blob(self, blob):
847 """Create a blob object in the pack with the supplied content."""
848 return self.maybe_write(b'blob', blob)
850 def new_tree(self, shalist):
851 """Create a tree object in the pack."""
852 content = tree_encode(shalist)
853 return self.maybe_write(b'tree', content)
855 def new_commit(self, tree, parent,
856 author, adate_sec, adate_tz,
857 committer, cdate_sec, cdate_tz,
859 """Create a commit object in the pack. The date_sec values must be
860 epoch-seconds, and if a tz is None, the local timezone is assumed."""
861 content = create_commit_blob(tree, parent,
862 author, adate_sec, adate_tz,
863 committer, cdate_sec, cdate_tz,
865 return self.maybe_write(b'commit', content)
867 def _end(self, run_midx=True, abort=False):
868 # Ignores run_midx during abort
871 self.file, f = None, self.file
872 self.idx, idx = None, self.idx
873 self.parentfd, pfd, = None, self.parentfd
876 with finalized(pfd, lambda x: x is not None and os.close(x)), \
880 os.unlink(self.filename + b'.pack')
883 # update object count
885 cp = struct.pack('!i', self.count)
889 # calculate the pack sha1sum
892 for b in chunkyreader(f):
894 packbin = sum.digest()
897 fdatasync(f.fileno())
900 idx.write(self.filename + b'.idx', packbin)
901 nameprefix = os.path.join(self.repo_dir,
902 b'objects/pack/pack-' + hexlify(packbin))
903 if os.path.exists(self.filename + b'.map'):
904 os.unlink(self.filename + b'.map')
905 os.rename(self.filename + b'.pack', nameprefix + b'.pack')
906 os.rename(self.filename + b'.idx', nameprefix + b'.idx')
909 auto_midx(os.path.join(self.repo_dir, b'objects/pack'))
910 if self.on_pack_finish:
911 self.on_pack_finish(nameprefix)
915 """Remove the pack file from disk."""
916 self._end(abort=True)
918 def breakpoint(self):
919 """Clear byte and object counts and return the last processed id."""
920 id = self._end(self.run_midx)
921 self.outbytes = self.count = 0
924 def close(self, run_midx=True):
925 """Close the pack file and move it to its definitive path."""
926 return self._end(run_midx=run_midx)
929 class PackIdxV2Writer:
931 self.idx = list(list() for i in range(256))
934 def add(self, sha, crc, offs):
937 self.idx[byte_int(sha[0])].append((sha, crc, offs))
939 def write(self, filename, packbin):
941 for section in self.idx:
942 for entry in section:
943 if entry[2] >= 2**31:
946 # Length: header + fan-out + shas-and-crcs + overflow-offsets
947 index_len = 8 + (4 * 256) + (28 * self.count) + (8 * ofs64_count)
949 idx_f = open(filename, 'w+b')
951 idx_f.truncate(index_len)
952 fdatasync(idx_f.fileno())
953 idx_map = mmap_readwrite(idx_f, close=False)
955 count = _helpers.write_idx(filename, idx_map, self.idx,
957 assert(count == self.count)
964 idx_f = open(filename, 'a+b')
969 b = idx_f.read(8 + 4*256)
972 for b in chunkyreader(idx_f, 20 * self.count):
975 for b in chunkyreader(idx_f):
977 idx_f.write(idx_sum.digest())
978 fdatasync(idx_f.fileno())
983 def list_refs(patterns=None, repo_dir=None,
984 limit_to_heads=False, limit_to_tags=False):
985 """Yield (refname, hash) tuples for all repository refs unless
986 patterns are specified. In that case, only include tuples for
987 refs matching those patterns (cf. git-show-ref(1)). The limits
988 restrict the result items to refs/heads or refs/tags. If both
989 limits are specified, items from both sources will be included.
992 argv = [b'git', b'show-ref']
994 argv.append(b'--heads')
996 argv.append(b'--tags')
999 argv.extend(patterns)
1000 p = subprocess.Popen(argv, env=_gitenv(repo_dir), stdout=subprocess.PIPE,
1002 out = p.stdout.read().strip()
1003 rv = p.wait() # not fatal
1007 for d in out.split(b'\n'):
1008 sha, name = d.split(b' ', 1)
1009 yield name, unhexlify(sha)
1012 def read_ref(refname, repo_dir = None):
1013 """Get the commit id of the most recent commit made on a given ref."""
1014 refs = list_refs(patterns=[refname], repo_dir=repo_dir, limit_to_heads=True)
1015 l = tuple(islice(refs, 2))
1023 def rev_list_invocation(ref_or_refs, format=None):
1024 if isinstance(ref_or_refs, bytes):
1025 refs = (ref_or_refs,)
1028 argv = [b'git', b'rev-list']
1031 argv.append(b'--pretty=format:' + format)
1033 assert not ref.startswith(b'-')
1039 def rev_list(ref_or_refs, parse=None, format=None, repo_dir=None):
1040 """Yield information about commits as per "git rev-list". If a format
1041 is not provided, yield one hex hash at a time. If a format is
1042 provided, pass it to rev-list and call parse(git_stdout) for each
1043 commit with the stream positioned just after the rev-list "commit
1044 HASH" header line. When a format is provided yield (oidx,
1045 parse(git_stdout)) for each commit.
1048 assert bool(parse) == bool(format)
1049 p = subprocess.Popen(rev_list_invocation(ref_or_refs,
1051 env=_gitenv(repo_dir),
1052 stdout = subprocess.PIPE,
1055 for line in p.stdout:
1058 line = p.stdout.readline()
1061 if not s.startswith(b'commit '):
1062 raise Exception('unexpected line ' + repr(s))
1065 yield s, parse(p.stdout)
1066 line = p.stdout.readline()
1068 rv = p.wait() # not fatal
1070 raise GitError('git rev-list returned error %d' % rv)
1073 def rev_parse(committish, repo_dir=None):
1074 """Resolve the full hash for 'committish', if it exists.
1076 Should be roughly equivalent to 'git rev-parse'.
1078 Returns the hex value of the hash if it is found, None if 'committish' does
1079 not correspond to anything.
1081 head = read_ref(committish, repo_dir=repo_dir)
1083 debug2("resolved from ref: commit = %s\n" % hexlify(head))
1086 pL = PackIdxList(repo(b'objects/pack', repo_dir=repo_dir))
1088 if len(committish) == 40:
1090 hash = unhexlify(committish)
1100 def update_ref(refname, newval, oldval, repo_dir=None):
1101 """Update a repository reference."""
1104 assert refname.startswith(b'refs/heads/') \
1105 or refname.startswith(b'refs/tags/')
1106 p = subprocess.Popen([b'git', b'update-ref', refname,
1107 hexlify(newval), hexlify(oldval)],
1108 env=_gitenv(repo_dir),
1110 _git_wait(b'git update-ref', p)
1113 def delete_ref(refname, oldvalue=None):
1114 """Delete a repository reference (see git update-ref(1))."""
1115 assert refname.startswith(b'refs/')
1116 oldvalue = [] if not oldvalue else [oldvalue]
1117 p = subprocess.Popen([b'git', b'update-ref', b'-d', refname] + oldvalue,
1120 _git_wait('git update-ref', p)
1123 def guess_repo(path=None):
1124 """Set the path value in the global variable "repodir".
1125 This makes bup look for an existing bup repository, but not fail if a
1126 repository doesn't exist. Usually, if you are interacting with a bup
1127 repository, you would not be calling this function but using
1128 check_repo_or_die().
1134 repodir = environ.get(b'BUP_DIR')
1136 repodir = os.path.expanduser(b'~/.bup')
1139 def init_repo(path=None):
1140 """Create the Git bare repository for bup in a given path."""
1142 d = repo() # appends a / to the path
1143 parent = os.path.dirname(os.path.dirname(d))
1144 if parent and not os.path.exists(parent):
1145 raise GitError('parent directory "%s" does not exist\n'
1147 if os.path.exists(d) and not os.path.isdir(os.path.join(d, b'.')):
1148 raise GitError('"%s" exists but is not a directory\n' % path_msg(d))
1149 p = subprocess.Popen([b'git', b'--bare', b'init'], stdout=sys.stderr,
1152 _git_wait('git init', p)
1153 # Force the index version configuration in order to ensure bup works
1154 # regardless of the version of the installed Git binary.
1155 p = subprocess.Popen([b'git', b'config', b'pack.indexVersion', '2'],
1156 stdout=sys.stderr, env=_gitenv(), close_fds=True)
1157 _git_wait('git config', p)
1159 p = subprocess.Popen([b'git', b'config', b'core.logAllRefUpdates', b'true'],
1160 stdout=sys.stderr, env=_gitenv(), close_fds=True)
1161 _git_wait('git config', p)
1164 def check_repo_or_die(path=None):
1165 """Check to see if a bup repository probably exists, and abort if not."""
1168 pst = stat_if_exists(top + b'/objects/pack')
1169 if pst and stat.S_ISDIR(pst.st_mode):
1172 top_st = stat_if_exists(top)
1174 log('error: repository %r does not exist (see "bup help init")\n'
1177 log('error: %s is not a repository\n' % path_msg(top))
1181 def is_suitable_git(ver_str):
1182 if not ver_str.startswith(b'git version '):
1183 return 'unrecognized'
1184 ver_str = ver_str[len(b'git version '):]
1185 if ver_str.startswith(b'0.'):
1186 return 'insufficient'
1187 if ver_str.startswith(b'1.'):
1188 if re.match(br'1\.[012345]rc', ver_str):
1189 return 'insufficient'
1190 if re.match(br'1\.[01234]\.', ver_str):
1191 return 'insufficient'
1192 if re.match(br'1\.5\.[012345]($|\.)', ver_str):
1193 return 'insufficient'
1194 if re.match(br'1\.5\.6-rc', ver_str):
1195 return 'insufficient'
1197 if re.match(br'[0-9]+(\.|$)?', ver_str):
1203 def require_suitable_git(ver_str=None):
1204 """Raise GitError if the version of git isn't suitable.
1206 Rely on ver_str when provided, rather than invoking the git in the
1211 if _git_great is not None:
1213 if environ.get(b'BUP_GIT_VERSION_IS_FINE', b'').lower() \
1214 in (b'yes', b'true', b'1'):
1218 ver_str, _, _ = _git_exo([b'git', b'--version'])
1219 status = is_suitable_git(ver_str)
1220 if status == 'unrecognized':
1221 raise GitError('Unexpected git --version output: %r' % ver_str)
1222 if status == 'insufficient':
1223 log('error: git version must be at least 1.5.6\n')
1225 if status == 'suitable':
1231 class _AbortableIter:
1232 def __init__(self, it, onabort = None):
1234 self.onabort = onabort
1242 return next(self.it)
1243 except StopIteration as e:
1253 """Abort iteration and call the abortion callback, if needed."""
1264 """Link to 'git cat-file' that is used to retrieve blob data."""
1265 def __init__(self, repo_dir = None):
1266 require_suitable_git()
1267 self.repo_dir = repo_dir
1268 self.p = self.inprogress = None
1270 def close(self, wait=False):
1276 self.inprogress = None
1284 self.p = subprocess.Popen([b'git', b'cat-file', b'--batch'],
1285 stdin=subprocess.PIPE,
1286 stdout=subprocess.PIPE,
1289 env=_gitenv(self.repo_dir))
1292 """Yield (oidx, type, size), followed by the data referred to by ref.
1293 If ref does not exist, only yield (None, None, None).
1296 if not self.p or self.p.poll() != None:
1299 poll_result = self.p.poll()
1300 assert(poll_result == None)
1302 log('get: opening %r while %r is open\n' % (ref, self.inprogress))
1303 assert(not self.inprogress)
1304 assert ref.find(b'\n') < 0
1305 assert ref.find(b'\r') < 0
1306 assert not ref.startswith(b'-')
1307 self.inprogress = ref
1308 self.p.stdin.write(ref + b'\n')
1309 self.p.stdin.flush()
1310 hdr = self.p.stdout.readline()
1312 raise GitError('unexpected cat-file EOF (last request: %r, exit: %s)'
1313 % (ref, self.p.poll() or 'none'))
1314 if hdr.endswith(b' missing\n'):
1315 self.inprogress = None
1316 yield None, None, None
1318 info = hdr.split(b' ')
1319 if len(info) != 3 or len(info[0]) != 40:
1320 raise GitError('expected object (id, type, size), got %r' % info)
1321 oidx, typ, size = info
1323 it = _AbortableIter(chunkyreader(self.p.stdout, size),
1326 yield oidx, typ, size
1329 readline_result = self.p.stdout.readline()
1330 assert readline_result == b'\n'
1331 self.inprogress = None
1332 except Exception as e:
1336 def _join(self, it):
1337 _, typ, _ = next(it)
1341 elif typ == b'tree':
1342 treefile = b''.join(it)
1343 for (mode, name, sha) in tree_decode(treefile):
1344 for blob in self.join(hexlify(sha)):
1346 elif typ == b'commit':
1347 treeline = b''.join(it).split(b'\n')[0]
1348 assert treeline.startswith(b'tree ')
1349 for blob in self.join(treeline[5:]):
1352 raise GitError('invalid object type %r: expected blob/tree/commit'
1356 """Generate a list of the content of all blobs that can be reached
1357 from an object. The hash given in 'id' must point to a blob, a tree
1358 or a commit. The content of all blobs that can be seen from trees or
1359 commits will be added to the list.
1361 for d in self._join(self.get(id)):
1367 def cp(repo_dir=None):
1368 """Create a CatPipe object or reuse the already existing one."""
1371 repo_dir = repodir or repo()
1372 repo_dir = os.path.abspath(repo_dir)
1373 cp = _cp.get(repo_dir)
1375 cp = CatPipe(repo_dir)
1380 def close_catpipes():
1381 # FIXME: chain exceptions
1383 _, cp = _cp.popitem()
1387 def tags(repo_dir = None):
1388 """Return a dictionary of all tags in the form {hash: [tag_names, ...]}."""
1390 for n, c in list_refs(repo_dir = repo_dir, limit_to_tags=True):
1391 assert n.startswith(b'refs/tags/')
1395 tags[c].append(name) # more than one tag can point at 'c'
1399 class MissingObject(KeyError):
1400 def __init__(self, oid):
1402 KeyError.__init__(self, 'object %r is missing' % hexlify(oid))
1405 WalkItem = namedtuple('WalkItem', ['oid', 'type', 'mode',
1406 'path', 'chunk_path', 'data'])
1407 # The path is the mangled path, and if an item represents a fragment
1408 # of a chunked file, the chunk_path will be the chunked subtree path
1409 # for the chunk, i.e. ['', '2d3115e', ...]. The top-level path for a
1410 # chunked file will have a chunk_path of ['']. So some chunk subtree
1411 # of the file '/foo/bar/baz' might look like this:
1413 # item.path = ['foo', 'bar', 'baz.bup']
1414 # item.chunk_path = ['', '2d3115e', '016b097']
1415 # item.type = 'tree'
1419 def walk_object(get_ref, oidx, stop_at=None, include_data=None):
1420 """Yield everything reachable from oidx via get_ref (which must behave
1421 like CatPipe get) as a WalkItem, stopping whenever stop_at(oidx)
1422 returns true. Throw MissingObject if a hash encountered is
1423 missing from the repository, and don't read or return blob content
1424 in the data field unless include_data is set.
1427 # Maintain the pending stack on the heap to avoid stack overflow
1428 pending = [(oidx, [], [], None)]
1430 oidx, parent_path, chunk_path, mode = pending.pop()
1431 oid = unhexlify(oidx)
1432 if stop_at and stop_at(oidx):
1435 if (not include_data) and mode and stat.S_ISREG(mode):
1436 # If the object is a "regular file", then it's a leaf in
1437 # the graph, so we can skip reading the data if the caller
1438 # hasn't requested it.
1439 yield WalkItem(oid=oid, type=b'blob',
1440 chunk_path=chunk_path, path=parent_path,
1445 item_it = get_ref(oidx)
1446 get_oidx, typ, _ = next(item_it)
1448 raise MissingObject(unhexlify(oidx))
1449 if typ not in (b'blob', b'commit', b'tree'):
1450 raise Exception('unexpected repository object type %r' % typ)
1452 # FIXME: set the mode based on the type when the mode is None
1453 if typ == b'blob' and not include_data:
1454 # Dump data until we can ask cat_pipe not to fetch it
1455 for ignored in item_it:
1459 data = b''.join(item_it)
1461 yield WalkItem(oid=oid, type=typ,
1462 chunk_path=chunk_path, path=parent_path,
1464 data=(data if include_data else None))
1466 if typ == b'commit':
1467 commit_items = parse_commit(data)
1468 for pid in commit_items.parents:
1469 pending.append((pid, parent_path, chunk_path, mode))
1470 pending.append((commit_items.tree, parent_path, chunk_path,
1471 hashsplit.GIT_MODE_TREE))
1472 elif typ == b'tree':
1473 for mode, name, ent_id in tree_decode(data):
1474 demangled, bup_type = demangle_name(name, mode)
1476 sub_path = parent_path
1477 sub_chunk_path = chunk_path + [name]
1479 sub_path = parent_path + [name]
1480 if bup_type == BUP_CHUNKED:
1481 sub_chunk_path = [b'']
1483 sub_chunk_path = chunk_path
1484 pending.append((hexlify(ent_id), sub_path, sub_chunk_path,