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)))
617 midxl.sort(key=lambda ix:
618 (-len(ix), -xstat.stat(ix.name).st_mtime))
621 for sub in ix.idxnames:
622 found = d.get(os.path.join(self.dir, sub))
623 if not found or isinstance(found, PackIdx):
624 # doesn't exist, or exists but not in a midx
629 for name in ix.idxnames:
630 d[os.path.join(self.dir, name)] = ix
631 elif not ix.force_keep:
632 debug1('midx: removing redundant: %s\n'
633 % path_msg(os.path.basename(ix.name)))
636 for full in glob.glob(os.path.join(self.dir, b'*.idx')):
640 except GitError as e:
644 bfull = os.path.join(self.dir, b'bup.bloom')
645 self.packs = list(set(d.values()))
646 self.packs.sort(reverse=True, key=lambda x: len(x))
647 if self.bloom is None and os.path.exists(bfull):
648 self.bloom = bloom.ShaBloom(bfull)
650 if self.bloom and self.bloom.valid() and len(self.bloom) >= len(self):
654 self.bloom, bloom_tmp = None, self.bloom
656 except BaseException as ex:
657 with pending_raise(ex):
661 debug1('PackIdxList: using %d index%s.\n'
662 % (len(self.packs), len(self.packs)!=1 and 'es' or ''))
665 """Insert an additional object in the list."""
669 def open_idx(filename):
670 if filename.endswith(b'.idx'):
671 f = open(filename, 'rb')
673 if header[0:4] == b'\377tOc':
674 version = struct.unpack('!I', header[4:8])[0]
676 return PackIdxV2(filename, f)
678 raise GitError('%s: expected idx file version 2, got %d'
679 % (path_msg(filename), version))
680 elif len(header) == 8 and header[0:4] < b'\377tOc':
681 return PackIdxV1(filename, f)
683 raise GitError('%s: unrecognized idx file header'
684 % path_msg(filename))
685 elif filename.endswith(b'.midx'):
686 return midx.PackMidx(filename)
688 raise GitError('idx filenames must end with .idx or .midx')
691 def idxmerge(idxlist, final_progress=True):
692 """Generate a list of all the objects reachable in a PackIdxList."""
693 def pfunc(count, total):
694 qprogress('Reading indexes: %.2f%% (%d/%d)\r'
695 % (count*100.0/total, count, total))
696 def pfinal(count, total):
698 progress('Reading indexes: %.2f%% (%d/%d), done.\n'
699 % (100, total, total))
700 return merge_iter(idxlist, 10024, pfunc, pfinal)
703 def create_commit_blob(tree, parent,
704 author, adate_sec, adate_tz,
705 committer, cdate_sec, cdate_tz,
707 if adate_tz is not None:
708 adate_str = _git_date_str(adate_sec, adate_tz)
710 adate_str = _local_git_date_str(adate_sec)
711 if cdate_tz is not None:
712 cdate_str = _git_date_str(cdate_sec, cdate_tz)
714 cdate_str = _local_git_date_str(cdate_sec)
716 if tree: l.append(b'tree %s' % hexlify(tree))
717 if parent: l.append(b'parent %s' % hexlify(parent))
718 if author: l.append(b'author %s %s' % (author, adate_str))
719 if committer: l.append(b'committer %s %s' % (committer, cdate_str))
725 def _make_objcache():
726 return PackIdxList(repo(b'objects/pack'))
728 # bup-gc assumes that it can disable all PackWriter activities
729 # (bloom/midx/cache) via the constructor and close() arguments.
732 """Writes Git objects inside a pack file."""
733 def __init__(self, objcache_maker=_make_objcache, compression_level=1,
734 run_midx=True, on_pack_finish=None,
735 max_pack_size=None, max_pack_objects=None, repo_dir=None):
736 self.repo_dir = repo_dir or repo()
743 self.objcache_maker = objcache_maker
745 self.compression_level = compression_level
746 self.run_midx=run_midx
747 self.on_pack_finish = on_pack_finish
748 if not max_pack_size:
749 max_pack_size = git_config_get(b'pack.packSizeLimit',
750 repo_dir=self.repo_dir,
752 if not max_pack_size:
753 # larger packs slow down pruning
754 max_pack_size = 1000 * 1000 * 1000
755 self.max_pack_size = max_pack_size
756 # cache memory usage is about 83 bytes per object
757 self.max_pack_objects = max_pack_objects if max_pack_objects \
758 else max(1, self.max_pack_size // 5000)
763 def __exit__(self, type, value, traceback):
764 with pending_raise(value, rethrow=False):
769 objdir = dir = os.path.join(self.repo_dir, b'objects')
770 fd, name = tempfile.mkstemp(suffix=b'.pack', dir=objdir)
772 self.file = os.fdopen(fd, 'w+b')
777 self.parentfd = os.open(objdir, os.O_RDONLY)
783 assert name.endswith(b'.pack')
784 self.filename = name[:-5]
785 self.file.write(b'PACK\0\0\0\2\0\0\0\0')
786 self.idx = PackIdxV2Writer()
788 def _raw_write(self, datalist, sha):
791 # in case we get interrupted (eg. KeyboardInterrupt), it's best if
792 # the file never has a *partial* blob. So let's make sure it's
793 # all-or-nothing. (The blob shouldn't be very big anyway, thanks
794 # to our hashsplit algorithm.) f.write() does its own buffering,
795 # but that's okay because we'll flush it in _end().
796 oneblob = b''.join(datalist)
802 crc = zlib.crc32(oneblob) & 0xffffffff
803 self._update_idx(sha, crc, nw)
808 def _update_idx(self, sha, crc, size):
811 self.idx.add(sha, crc, self.file.tell() - size)
813 def _write(self, sha, type, content):
817 sha = calc_hash(type, content)
818 size, crc = self._raw_write(_encode_packobj(type, content,
819 self.compression_level),
821 if self.outbytes >= self.max_pack_size \
822 or self.count >= self.max_pack_objects:
826 def _require_objcache(self):
827 if self.objcache is None and self.objcache_maker:
828 self.objcache = self.objcache_maker()
829 if self.objcache is None:
831 "PackWriter not opened or can't check exists w/o objcache")
833 def exists(self, id, want_source=False):
834 """Return non-empty if an object is found in the object cache."""
835 self._require_objcache()
836 return self.objcache.exists(id, want_source=want_source)
838 def just_write(self, sha, type, content):
839 """Write an object to the pack file without checking for duplication."""
840 self._write(sha, type, content)
841 # If nothing else, gc doesn't have/want an objcache
842 if self.objcache is not None:
843 self.objcache.add(sha)
845 def maybe_write(self, type, content):
846 """Write an object to the pack file if not present and return its id."""
847 sha = calc_hash(type, content)
848 if not self.exists(sha):
849 self._require_objcache()
850 self.just_write(sha, type, content)
853 def new_blob(self, blob):
854 """Create a blob object in the pack with the supplied content."""
855 return self.maybe_write(b'blob', blob)
857 def new_tree(self, shalist):
858 """Create a tree object in the pack."""
859 content = tree_encode(shalist)
860 return self.maybe_write(b'tree', content)
862 def new_commit(self, tree, parent,
863 author, adate_sec, adate_tz,
864 committer, cdate_sec, cdate_tz,
866 """Create a commit object in the pack. The date_sec values must be
867 epoch-seconds, and if a tz is None, the local timezone is assumed."""
868 content = create_commit_blob(tree, parent,
869 author, adate_sec, adate_tz,
870 committer, cdate_sec, cdate_tz,
872 return self.maybe_write(b'commit', content)
874 def _end(self, run_midx=True, abort=False):
875 # Ignores run_midx during abort
878 self.file, f = None, self.file
879 self.idx, idx = None, self.idx
880 self.parentfd, pfd, = None, self.parentfd
883 with finalized(pfd, lambda x: x is not None and os.close(x)), \
887 os.unlink(self.filename + b'.pack')
890 # update object count
892 cp = struct.pack('!i', self.count)
896 # calculate the pack sha1sum
899 for b in chunkyreader(f):
901 packbin = sum.digest()
904 fdatasync(f.fileno())
907 idx.write(self.filename + b'.idx', packbin)
908 nameprefix = os.path.join(self.repo_dir,
909 b'objects/pack/pack-' + hexlify(packbin))
910 if os.path.exists(self.filename + b'.map'):
911 os.unlink(self.filename + b'.map')
912 os.rename(self.filename + b'.pack', nameprefix + b'.pack')
913 os.rename(self.filename + b'.idx', nameprefix + b'.idx')
916 auto_midx(os.path.join(self.repo_dir, b'objects/pack'))
917 if self.on_pack_finish:
918 self.on_pack_finish(nameprefix)
922 """Remove the pack file from disk."""
923 self._end(abort=True)
925 def breakpoint(self):
926 """Clear byte and object counts and return the last processed id."""
927 id = self._end(self.run_midx)
928 self.outbytes = self.count = 0
931 def close(self, run_midx=True):
932 """Close the pack file and move it to its definitive path."""
933 return self._end(run_midx=run_midx)
936 class PackIdxV2Writer:
938 self.idx = list(list() for i in range(256))
941 def add(self, sha, crc, offs):
944 self.idx[byte_int(sha[0])].append((sha, crc, offs))
946 def write(self, filename, packbin):
948 for section in self.idx:
949 for entry in section:
950 if entry[2] >= 2**31:
953 # Length: header + fan-out + shas-and-crcs + overflow-offsets
954 index_len = 8 + (4 * 256) + (28 * self.count) + (8 * ofs64_count)
956 idx_f = open(filename, 'w+b')
958 idx_f.truncate(index_len)
959 fdatasync(idx_f.fileno())
960 idx_map = mmap_readwrite(idx_f, close=False)
962 count = _helpers.write_idx(filename, idx_map, self.idx,
964 assert(count == self.count)
971 idx_f = open(filename, 'a+b')
976 b = idx_f.read(8 + 4*256)
979 for b in chunkyreader(idx_f, 20 * self.count):
982 for b in chunkyreader(idx_f):
984 idx_f.write(idx_sum.digest())
985 fdatasync(idx_f.fileno())
990 def list_refs(patterns=None, repo_dir=None,
991 limit_to_heads=False, limit_to_tags=False):
992 """Yield (refname, hash) tuples for all repository refs unless
993 patterns are specified. In that case, only include tuples for
994 refs matching those patterns (cf. git-show-ref(1)). The limits
995 restrict the result items to refs/heads or refs/tags. If both
996 limits are specified, items from both sources will be included.
999 argv = [b'git', b'show-ref']
1001 argv.append(b'--heads')
1003 argv.append(b'--tags')
1006 argv.extend(patterns)
1007 p = subprocess.Popen(argv, env=_gitenv(repo_dir), stdout=subprocess.PIPE,
1009 out = p.stdout.read().strip()
1010 rv = p.wait() # not fatal
1014 for d in out.split(b'\n'):
1015 sha, name = d.split(b' ', 1)
1016 yield name, unhexlify(sha)
1019 def read_ref(refname, repo_dir = None):
1020 """Get the commit id of the most recent commit made on a given ref."""
1021 refs = list_refs(patterns=[refname], repo_dir=repo_dir, limit_to_heads=True)
1022 l = tuple(islice(refs, 2))
1030 def rev_list_invocation(ref_or_refs, format=None):
1031 if isinstance(ref_or_refs, bytes):
1032 refs = (ref_or_refs,)
1035 argv = [b'git', b'rev-list']
1038 argv.append(b'--pretty=format:' + format)
1040 assert not ref.startswith(b'-')
1046 def rev_list(ref_or_refs, parse=None, format=None, repo_dir=None):
1047 """Yield information about commits as per "git rev-list". If a format
1048 is not provided, yield one hex hash at a time. If a format is
1049 provided, pass it to rev-list and call parse(git_stdout) for each
1050 commit with the stream positioned just after the rev-list "commit
1051 HASH" header line. When a format is provided yield (oidx,
1052 parse(git_stdout)) for each commit.
1055 assert bool(parse) == bool(format)
1056 p = subprocess.Popen(rev_list_invocation(ref_or_refs,
1058 env=_gitenv(repo_dir),
1059 stdout = subprocess.PIPE,
1062 for line in p.stdout:
1065 line = p.stdout.readline()
1068 if not s.startswith(b'commit '):
1069 raise Exception('unexpected line ' + repr(s))
1072 yield s, parse(p.stdout)
1073 line = p.stdout.readline()
1075 rv = p.wait() # not fatal
1077 raise GitError('git rev-list returned error %d' % rv)
1080 def rev_parse(committish, repo_dir=None):
1081 """Resolve the full hash for 'committish', if it exists.
1083 Should be roughly equivalent to 'git rev-parse'.
1085 Returns the hex value of the hash if it is found, None if 'committish' does
1086 not correspond to anything.
1088 head = read_ref(committish, repo_dir=repo_dir)
1090 debug2("resolved from ref: commit = %s\n" % hexlify(head))
1093 pL = PackIdxList(repo(b'objects/pack', repo_dir=repo_dir))
1095 if len(committish) == 40:
1097 hash = unhexlify(committish)
1107 def update_ref(refname, newval, oldval, repo_dir=None):
1108 """Update a repository reference."""
1111 assert refname.startswith(b'refs/heads/') \
1112 or refname.startswith(b'refs/tags/')
1113 p = subprocess.Popen([b'git', b'update-ref', refname,
1114 hexlify(newval), hexlify(oldval)],
1115 env=_gitenv(repo_dir),
1117 _git_wait(b'git update-ref', p)
1120 def delete_ref(refname, oldvalue=None):
1121 """Delete a repository reference (see git update-ref(1))."""
1122 assert refname.startswith(b'refs/')
1123 oldvalue = [] if not oldvalue else [oldvalue]
1124 p = subprocess.Popen([b'git', b'update-ref', b'-d', refname] + oldvalue,
1127 _git_wait('git update-ref', p)
1130 def guess_repo(path=None):
1131 """Set the path value in the global variable "repodir".
1132 This makes bup look for an existing bup repository, but not fail if a
1133 repository doesn't exist. Usually, if you are interacting with a bup
1134 repository, you would not be calling this function but using
1135 check_repo_or_die().
1141 repodir = environ.get(b'BUP_DIR')
1143 repodir = os.path.expanduser(b'~/.bup')
1146 def init_repo(path=None):
1147 """Create the Git bare repository for bup in a given path."""
1149 d = repo() # appends a / to the path
1150 parent = os.path.dirname(os.path.dirname(d))
1151 if parent and not os.path.exists(parent):
1152 raise GitError('parent directory "%s" does not exist\n'
1154 if os.path.exists(d) and not os.path.isdir(os.path.join(d, b'.')):
1155 raise GitError('"%s" exists but is not a directory\n' % path_msg(d))
1156 p = subprocess.Popen([b'git', b'--bare', b'init'], stdout=sys.stderr,
1159 _git_wait('git init', p)
1160 # Force the index version configuration in order to ensure bup works
1161 # regardless of the version of the installed Git binary.
1162 p = subprocess.Popen([b'git', b'config', b'pack.indexVersion', '2'],
1163 stdout=sys.stderr, env=_gitenv(), close_fds=True)
1164 _git_wait('git config', p)
1166 p = subprocess.Popen([b'git', b'config', b'core.logAllRefUpdates', b'true'],
1167 stdout=sys.stderr, env=_gitenv(), close_fds=True)
1168 _git_wait('git config', p)
1171 def check_repo_or_die(path=None):
1172 """Check to see if a bup repository probably exists, and abort if not."""
1175 pst = stat_if_exists(top + b'/objects/pack')
1176 if pst and stat.S_ISDIR(pst.st_mode):
1179 top_st = stat_if_exists(top)
1181 log('error: repository %r does not exist (see "bup help init")\n'
1184 log('error: %s is not a repository\n' % path_msg(top))
1188 def is_suitable_git(ver_str):
1189 if not ver_str.startswith(b'git version '):
1190 return 'unrecognized'
1191 ver_str = ver_str[len(b'git version '):]
1192 if ver_str.startswith(b'0.'):
1193 return 'insufficient'
1194 if ver_str.startswith(b'1.'):
1195 if re.match(br'1\.[012345]rc', ver_str):
1196 return 'insufficient'
1197 if re.match(br'1\.[01234]\.', ver_str):
1198 return 'insufficient'
1199 if re.match(br'1\.5\.[012345]($|\.)', ver_str):
1200 return 'insufficient'
1201 if re.match(br'1\.5\.6-rc', ver_str):
1202 return 'insufficient'
1204 if re.match(br'[0-9]+(\.|$)?', ver_str):
1210 def require_suitable_git(ver_str=None):
1211 """Raise GitError if the version of git isn't suitable.
1213 Rely on ver_str when provided, rather than invoking the git in the
1218 if _git_great is not None:
1220 if environ.get(b'BUP_GIT_VERSION_IS_FINE', b'').lower() \
1221 in (b'yes', b'true', b'1'):
1225 ver_str, _, _ = _git_exo([b'git', b'--version'])
1226 status = is_suitable_git(ver_str)
1227 if status == 'unrecognized':
1228 raise GitError('Unexpected git --version output: %r' % ver_str)
1229 if status == 'insufficient':
1230 log('error: git version must be at least 1.5.6\n')
1232 if status == 'suitable':
1239 """Link to 'git cat-file' that is used to retrieve blob data."""
1240 def __init__(self, repo_dir = None):
1241 require_suitable_git()
1242 self.repo_dir = repo_dir
1243 self.p = self.inprogress = None
1245 def close(self, wait=False):
1246 self.p, p = None, self.p
1247 self.inprogress = None
1252 # This will handle pending exceptions correctly once
1262 self.p = subprocess.Popen([b'git', b'cat-file', b'--batch'],
1263 stdin=subprocess.PIPE,
1264 stdout=subprocess.PIPE,
1267 env=_gitenv(self.repo_dir))
1270 """Yield (oidx, type, size), followed by the data referred to by ref.
1271 If ref does not exist, only yield (None, None, None).
1274 if not self.p or self.p.poll() != None:
1277 poll_result = self.p.poll()
1278 assert(poll_result == None)
1280 log('get: opening %r while %r is open\n' % (ref, self.inprogress))
1281 assert(not self.inprogress)
1282 assert ref.find(b'\n') < 0
1283 assert ref.find(b'\r') < 0
1284 assert not ref.startswith(b'-')
1285 self.inprogress = ref
1286 self.p.stdin.write(ref + b'\n')
1287 self.p.stdin.flush()
1288 hdr = self.p.stdout.readline()
1290 raise GitError('unexpected cat-file EOF (last request: %r, exit: %s)'
1291 % (ref, self.p.poll() or 'none'))
1292 if hdr.endswith(b' missing\n'):
1293 self.inprogress = None
1294 yield None, None, None
1296 info = hdr.split(b' ')
1297 if len(info) != 3 or len(info[0]) != 40:
1298 raise GitError('expected object (id, type, size), got %r' % info)
1299 oidx, typ, size = info
1302 it = chunkyreader(self.p.stdout, size)
1303 yield oidx, typ, size
1304 for blob in chunkyreader(self.p.stdout, size):
1306 readline_result = self.p.stdout.readline()
1307 assert readline_result == b'\n'
1308 self.inprogress = None
1309 except Exception as ex:
1310 with pending_raise(ex):
1313 def _join(self, it):
1314 _, typ, _ = next(it)
1318 elif typ == b'tree':
1319 treefile = b''.join(it)
1320 for (mode, name, sha) in tree_decode(treefile):
1321 for blob in self.join(hexlify(sha)):
1323 elif typ == b'commit':
1324 treeline = b''.join(it).split(b'\n')[0]
1325 assert treeline.startswith(b'tree ')
1326 for blob in self.join(treeline[5:]):
1329 raise GitError('invalid object type %r: expected blob/tree/commit'
1333 """Generate a list of the content of all blobs that can be reached
1334 from an object. The hash given in 'id' must point to a blob, a tree
1335 or a commit. The content of all blobs that can be seen from trees or
1336 commits will be added to the list.
1338 for d in self._join(self.get(id)):
1344 def cp(repo_dir=None):
1345 """Create a CatPipe object or reuse the already existing one."""
1348 repo_dir = repodir or repo()
1349 repo_dir = os.path.abspath(repo_dir)
1350 cp = _cp.get(repo_dir)
1352 cp = CatPipe(repo_dir)
1357 def close_catpipes():
1358 # FIXME: chain exceptions
1360 _, cp = _cp.popitem()
1364 def tags(repo_dir = None):
1365 """Return a dictionary of all tags in the form {hash: [tag_names, ...]}."""
1367 for n, c in list_refs(repo_dir = repo_dir, limit_to_tags=True):
1368 assert n.startswith(b'refs/tags/')
1372 tags[c].append(name) # more than one tag can point at 'c'
1376 class MissingObject(KeyError):
1377 def __init__(self, oid):
1379 KeyError.__init__(self, 'object %r is missing' % hexlify(oid))
1382 WalkItem = namedtuple('WalkItem', ['oid', 'type', 'mode',
1383 'path', 'chunk_path', 'data'])
1384 # The path is the mangled path, and if an item represents a fragment
1385 # of a chunked file, the chunk_path will be the chunked subtree path
1386 # for the chunk, i.e. ['', '2d3115e', ...]. The top-level path for a
1387 # chunked file will have a chunk_path of ['']. So some chunk subtree
1388 # of the file '/foo/bar/baz' might look like this:
1390 # item.path = ['foo', 'bar', 'baz.bup']
1391 # item.chunk_path = ['', '2d3115e', '016b097']
1392 # item.type = 'tree'
1396 def walk_object(get_ref, oidx, stop_at=None, include_data=None):
1397 """Yield everything reachable from oidx via get_ref (which must behave
1398 like CatPipe get) as a WalkItem, stopping whenever stop_at(oidx)
1399 returns true. Throw MissingObject if a hash encountered is
1400 missing from the repository, and don't read or return blob content
1401 in the data field unless include_data is set.
1404 # Maintain the pending stack on the heap to avoid stack overflow
1405 pending = [(oidx, [], [], None)]
1407 oidx, parent_path, chunk_path, mode = pending.pop()
1408 oid = unhexlify(oidx)
1409 if stop_at and stop_at(oidx):
1412 if (not include_data) and mode and stat.S_ISREG(mode):
1413 # If the object is a "regular file", then it's a leaf in
1414 # the graph, so we can skip reading the data if the caller
1415 # hasn't requested it.
1416 yield WalkItem(oid=oid, type=b'blob',
1417 chunk_path=chunk_path, path=parent_path,
1422 item_it = get_ref(oidx)
1423 get_oidx, typ, _ = next(item_it)
1425 raise MissingObject(unhexlify(oidx))
1426 if typ not in (b'blob', b'commit', b'tree'):
1427 raise Exception('unexpected repository object type %r' % typ)
1429 # FIXME: set the mode based on the type when the mode is None
1430 if typ == b'blob' and not include_data:
1431 # Dump data until we can ask cat_pipe not to fetch it
1432 for ignored in item_it:
1436 data = b''.join(item_it)
1438 yield WalkItem(oid=oid, type=typ,
1439 chunk_path=chunk_path, path=parent_path,
1441 data=(data if include_data else None))
1443 if typ == b'commit':
1444 commit_items = parse_commit(data)
1445 for pid in commit_items.parents:
1446 pending.append((pid, parent_path, chunk_path, mode))
1447 pending.append((commit_items.tree, parent_path, chunk_path,
1448 hashsplit.GIT_MODE_TREE))
1449 elif typ == b'tree':
1450 for mode, name, ent_id in tree_decode(data):
1451 demangled, bup_type = demangle_name(name, mode)
1453 sub_path = parent_path
1454 sub_chunk_path = chunk_path + [name]
1456 sub_path = parent_path + [name]
1457 if bup_type == BUP_CHUNKED:
1458 sub_chunk_path = [b'']
1460 sub_chunk_path = chunk_path
1461 pending.append((hexlify(ent_id), sub_path, sub_chunk_path,