bup repositories are in Git format. This library allows us to
interact with the Git data structures.
"""
-import os, sys, zlib, time, subprocess, struct, stat, re, tempfile, math, glob
-from bup.helpers import *
-from bup import _helpers, path
-
-MIDX_VERSION = 4
-
-"""Discussion of bloom constants for bup:
-
-There are four basic things to consider when building a bloom filter:
-The size, in bits, of the filter
-The capacity, in entries, of the filter
-The probability of a false positive that is tolerable
-The number of bits readily available to use for addresing filter bits
-
-There is one major tunable that is not directly related to the above:
-k: the number of bits set in the filter per entry
-
-Here's a wall of numbers showing the relationship between k; the ratio between
-the filter size in bits and the entries in the filter; and pfalse_positive:
-
-mn|k=3 |k=4 |k=5 |k=6 |k=7 |k=8 |k=9 |k=10 |k=11
- 8|3.05794|2.39687|2.16792|2.15771|2.29297|2.54917|2.92244|3.41909|4.05091
- 9|2.27780|1.65770|1.40703|1.32721|1.34892|1.44631|1.61138|1.84491|2.15259
-10|1.74106|1.18133|0.94309|0.84362|0.81937|0.84555|0.91270|1.01859|1.16495
-11|1.36005|0.86373|0.65018|0.55222|0.51259|0.50864|0.53098|0.57616|0.64387
-12|1.08231|0.64568|0.45945|0.37108|0.32939|0.31424|0.31695|0.33387|0.36380
-13|0.87517|0.49210|0.33183|0.25527|0.21689|0.19897|0.19384|0.19804|0.21013
-14|0.71759|0.38147|0.24433|0.17934|0.14601|0.12887|0.12127|0.12012|0.12399
-15|0.59562|0.30019|0.18303|0.12840|0.10028|0.08523|0.07749|0.07440|0.07468
-16|0.49977|0.23941|0.13925|0.09351|0.07015|0.05745|0.05049|0.04700|0.04587
-17|0.42340|0.19323|0.10742|0.06916|0.04990|0.03941|0.03350|0.03024|0.02870
-18|0.36181|0.15765|0.08392|0.05188|0.03604|0.02748|0.02260|0.01980|0.01827
-19|0.31160|0.12989|0.06632|0.03942|0.02640|0.01945|0.01549|0.01317|0.01182
-20|0.27026|0.10797|0.05296|0.03031|0.01959|0.01396|0.01077|0.00889|0.00777
-21|0.23591|0.09048|0.04269|0.02356|0.01471|0.01014|0.00759|0.00609|0.00518
-22|0.20714|0.07639|0.03473|0.01850|0.01117|0.00746|0.00542|0.00423|0.00350
-23|0.18287|0.06493|0.02847|0.01466|0.00856|0.00555|0.00392|0.00297|0.00240
-24|0.16224|0.05554|0.02352|0.01171|0.00663|0.00417|0.00286|0.00211|0.00166
-25|0.14459|0.04779|0.01957|0.00944|0.00518|0.00316|0.00211|0.00152|0.00116
-26|0.12942|0.04135|0.01639|0.00766|0.00408|0.00242|0.00157|0.00110|0.00082
-27|0.11629|0.03595|0.01381|0.00626|0.00324|0.00187|0.00118|0.00081|0.00059
-28|0.10489|0.03141|0.01170|0.00515|0.00259|0.00146|0.00090|0.00060|0.00043
-29|0.09492|0.02756|0.00996|0.00426|0.00209|0.00114|0.00069|0.00045|0.00031
-30|0.08618|0.02428|0.00853|0.00355|0.00169|0.00090|0.00053|0.00034|0.00023
-31|0.07848|0.02147|0.00733|0.00297|0.00138|0.00072|0.00041|0.00025|0.00017
-32|0.07167|0.01906|0.00633|0.00250|0.00113|0.00057|0.00032|0.00019|0.00013
-
-Here's a table showing available repository size for a given pfalse_positive
-and three values of k (assuming we only use the 160 bit SHA1 for addressing the
-filter and 8192bytes per object):
-
-pfalse|obj k=4 |cap k=4 |obj k=5 |cap k=5 |obj k=6 |cap k=6
-2.500%|139333497228|1038.11 TiB|558711157|4262.63 GiB|13815755|105.41 GiB
-1.000%|104489450934| 778.50 TiB|436090254|3327.10 GiB|11077519| 84.51 GiB
-0.125%| 57254889824| 426.58 TiB|261732190|1996.86 GiB| 7063017| 55.89 GiB
-
-This eliminates pretty neatly any k>6 as long as we use the raw SHA for
-addressing.
-
-filter size scales linearly with repository size for a given k and pfalse.
-
-Here's a table of filter sizes for a 1 TiB repository:
-
-pfalse| k=3 | k=4 | k=5 | k=6
-2.500%| 138.78 MiB | 126.26 MiB | 123.00 MiB | 123.37 MiB
-1.000%| 197.83 MiB | 168.36 MiB | 157.58 MiB | 153.87 MiB
-0.125%| 421.14 MiB | 307.26 MiB | 262.56 MiB | 241.32 MiB
-
-For bup:
-* We want the bloom filter to fit in memory; if it doesn't, the k pagefaults
-per lookup will be worse than the two required for midx.
-* We want the pfalse_positive to be low enough that the cost of sometimes
-faulting on the midx doesn't overcome the benefit of the bloom filter.
-* We have readily available 160 bits for addressing the filter.
-* We want to be able to have a single bloom address entire repositories of
-reasonable size.
-
-Based on these parameters, a combination of k=4 and k=5 provides the behavior
-that bup needs. As such, I've implemented bloom addressing, adding and
-checking functions in C for these two values. Because k=5 requires less space
-and gives better overall pfalse_positive perofrmance, it is preferred if a
-table with k=5 can represent the repository.
-
-None of this tells us what max_pfalse_positive to choose.
-
-Brandon Low <lostlogic@lostlogicx.com> 04-02-2011
-"""
-BLOOM_VERSION = 2
-MAX_BITS_EACH = 32 # Kinda arbitrary, but 4 bytes per entry is pretty big
-MAX_BLOOM_BITS = {4: 37, 5: 29} # 160/k-log2(8)
-MAX_PFALSE_POSITIVE = 1. # Totally arbitrary, needs benchmarking
+
+import errno, os, sys, zlib, time, subprocess, struct, stat, re, tempfile, glob
+from collections import namedtuple
+from itertools import islice
+
+from bup import _helpers, hashsplit, path, midx, bloom, xstat
+from bup.helpers import (Sha1, add_error, chunkyreader, debug1, debug2,
+ fdatasync,
+ hostname, localtime, log, merge_iter,
+ mmap_read, mmap_readwrite,
+ progress, qprogress, stat_if_exists,
+ unlink, username, userfullname,
+ utc_offset_str)
+
+
+max_pack_size = 1000*1000*1000 # larger packs will slow down pruning
+max_pack_objects = 200*1000 # cache memory usage is about 83 bytes per object
verbose = 0
ignore_midx = 0
-home_repodir = os.path.expanduser('~/.bup')
repodir = None
_typemap = { 'blob':3, 'tree':2, 'commit':1, 'tag':4 }
pass
-def repo(sub = ''):
+def parse_tz_offset(s):
+ """UTC offset in seconds."""
+ tz_off = (int(s[1:3]) * 60 * 60) + (int(s[3:5]) * 60)
+ if s[0] == '-':
+ return - tz_off
+ return tz_off
+
+
+# FIXME: derived from http://git.rsbx.net/Documents/Git_Data_Formats.txt
+# Make sure that's authoritative.
+_start_end_char = r'[^ .,:;<>"\'\0\n]'
+_content_char = r'[^\0\n<>]'
+_safe_str_rx = '(?:%s{1,2}|(?:%s%s*%s))' \
+ % (_start_end_char,
+ _start_end_char, _content_char, _start_end_char)
+_tz_rx = r'[-+]\d\d[0-5]\d'
+_parent_rx = r'(?:parent [abcdefABCDEF0123456789]{40}\n)'
+_commit_rx = re.compile(r'''tree (?P<tree>[abcdefABCDEF0123456789]{40})
+(?P<parents>%s*)author (?P<author_name>%s) <(?P<author_mail>%s)> (?P<asec>\d+) (?P<atz>%s)
+committer (?P<committer_name>%s) <(?P<committer_mail>%s)> (?P<csec>\d+) (?P<ctz>%s)
+
+(?P<message>(?:.|\n)*)''' % (_parent_rx,
+ _safe_str_rx, _safe_str_rx, _tz_rx,
+ _safe_str_rx, _safe_str_rx, _tz_rx))
+_parent_hash_rx = re.compile(r'\s*parent ([abcdefABCDEF0123456789]{40})\s*')
+
+
+# Note that the author_sec and committer_sec values are (UTC) epoch seconds.
+CommitInfo = namedtuple('CommitInfo', ['tree', 'parents',
+ 'author_name', 'author_mail',
+ 'author_sec', 'author_offset',
+ 'committer_name', 'committer_mail',
+ 'committer_sec', 'committer_offset',
+ 'message'])
+
+def parse_commit(content):
+ commit_match = re.match(_commit_rx, content)
+ if not commit_match:
+ raise Exception('cannot parse commit %r' % content)
+ matches = commit_match.groupdict()
+ return CommitInfo(tree=matches['tree'],
+ parents=re.findall(_parent_hash_rx, matches['parents']),
+ author_name=matches['author_name'],
+ author_mail=matches['author_mail'],
+ author_sec=int(matches['asec']),
+ author_offset=parse_tz_offset(matches['atz']),
+ committer_name=matches['committer_name'],
+ committer_mail=matches['committer_mail'],
+ committer_sec=int(matches['csec']),
+ committer_offset=parse_tz_offset(matches['ctz']),
+ message=matches['message'])
+
+
+def get_commit_items(id, cp):
+ commit_it = cp.get(id)
+ assert(commit_it.next() == 'commit')
+ commit_content = ''.join(commit_it)
+ return parse_commit(commit_content)
+
+
+def _local_git_date_str(epoch_sec):
+ return '%d %s' % (epoch_sec, utc_offset_str(epoch_sec))
+
+
+def _git_date_str(epoch_sec, tz_offset_sec):
+ offs = tz_offset_sec // 60
+ return '%d %s%02d%02d' \
+ % (epoch_sec,
+ '+' if offs >= 0 else '-',
+ abs(offs) // 60,
+ abs(offs) % 60)
+
+
+def repo(sub = '', repo_dir=None):
"""Get the path to the git repository or one of its subdirectories."""
global repodir
- if not repodir:
+ repo_dir = repo_dir or repodir
+ if not repo_dir:
raise GitError('You should call check_repo_or_die()')
# If there's a .git subdirectory, then the actual repo is in there.
- gd = os.path.join(repodir, '.git')
+ gd = os.path.join(repo_dir, '.git')
if os.path.exists(gd):
repodir = gd
- return os.path.join(repodir, sub)
+ return os.path.join(repo_dir, sub)
+
+
+def shorten_hash(s):
+ return re.sub(r'([^0-9a-z]|\b)([0-9a-z]{7})[0-9a-z]{33}([^0-9a-z]|\b)',
+ r'\1\2*\3', s)
+
+
+def repo_rel(path):
+ full = os.path.abspath(path)
+ fullrepo = os.path.abspath(repo(''))
+ if not fullrepo.endswith('/'):
+ fullrepo += '/'
+ if full.startswith(fullrepo):
+ path = full[len(fullrepo):]
+ if path.startswith('index-cache/'):
+ path = path[len('index-cache/'):]
+ return shorten_hash(path)
+
+
+def all_packdirs():
+ paths = [repo('objects/pack')]
+ paths += glob.glob(repo('index-cache/*/.'))
+ return paths
def auto_midx(objdir):
args = [path.exe(), 'midx', '--auto', '--dir', objdir]
try:
rv = subprocess.call(args, stdout=open('/dev/null', 'w'))
- except OSError, e:
+ except OSError as e:
# make sure 'args' gets printed to help with debugging
add_error('%r: exception: %s' % (args, e))
raise
args = [path.exe(), 'bloom', '--dir', objdir]
try:
rv = subprocess.call(args, stdout=open('/dev/null', 'w'))
- except OSError, e:
+ except OSError as e:
# make sure 'args' gets printed to help with debugging
add_error('%r: exception: %s' % (args, e))
raise
"""Mangle a file name to present an abstract name for segmented files.
Mangled file names will have the ".bup" extension added to them. If a
file's name already ends with ".bup", a ".bupl" extension is added to
- disambiguate normal files from semgmented ones.
+ disambiguate normal files from segmented ones.
"""
if stat.S_ISREG(mode) and not stat.S_ISREG(gitmode):
+ assert(stat.S_ISDIR(gitmode))
return name + '.bup'
elif name.endswith('.bup') or name[:-1].endswith('.bup'):
return name + '.bupl'
(BUP_NORMAL, BUP_CHUNKED) = (0,1)
-def demangle_name(name):
+def demangle_name(name, mode):
"""Remove name mangling from a file name, if necessary.
The return value is a tuple (demangled_filename,mode), where mode is one of
the following:
* BUP_NORMAL : files that should be read as-is from the repository
- * BUP_CHUNKED : files that were chunked and need to be assembled
+ * BUP_CHUNKED : files that were chunked and need to be reassembled
- For more information on the name mangling algorythm, see mangle_name()
+ For more information on the name mangling algorithm, see mangle_name()
"""
if name.endswith('.bupl'):
return (name[:-5], BUP_NORMAL)
elif name.endswith('.bup'):
return (name[:-4], BUP_CHUNKED)
+ elif name.endswith('.bupm'):
+ return (name[:-5],
+ BUP_CHUNKED if stat.S_ISDIR(mode) else BUP_NORMAL)
else:
return (name, BUP_NORMAL)
-def _encode_packobj(type, content):
+def calc_hash(type, content):
+ """Calculate some content's hash in the Git fashion."""
+ header = '%s %d\0' % (type, len(content))
+ sum = Sha1(header)
+ sum.update(content)
+ return sum.digest()
+
+
+def shalist_item_sort_key(ent):
+ (mode, name, id) = ent
+ assert(mode+0 == mode)
+ if stat.S_ISDIR(mode):
+ return name + '/'
+ else:
+ return name
+
+
+def tree_encode(shalist):
+ """Generate a git tree object from (mode,name,hash) tuples."""
+ shalist = sorted(shalist, key = shalist_item_sort_key)
+ l = []
+ for (mode,name,bin) in shalist:
+ assert(mode)
+ assert(mode+0 == mode)
+ assert(name)
+ assert(len(bin) == 20)
+ s = '%o %s\0%s' % (mode,name,bin)
+ assert(s[0] != '0') # 0-padded octal is not acceptable in a git tree
+ l.append(s)
+ return ''.join(l)
+
+
+def tree_decode(buf):
+ """Generate a list of (mode,name,hash) from the git tree object in buf."""
+ ofs = 0
+ while ofs < len(buf):
+ z = buf.find('\0', ofs)
+ assert(z > ofs)
+ spl = buf[ofs:z].split(' ', 1)
+ assert(len(spl) == 2)
+ mode,name = spl
+ sha = buf[z+1:z+1+20]
+ ofs = z+1+20
+ yield (int(mode, 8), name, sha)
+
+
+def _encode_packobj(type, content, compression_level=1):
+ if compression_level not in (0, 1, 2, 3, 4, 5, 6, 7, 8, 9):
+ raise ValueError('invalid compression level %s' % compression_level)
szout = ''
sz = len(content)
szbits = (sz & 0x0f) | (_typemap[type]<<4)
break
szbits = sz & 0x7f
sz >>= 7
- z = zlib.compressobj(1)
+ z = zlib.compressobj(compression_level)
yield szout
yield z.compress(content)
yield z.flush()
-def _encode_looseobj(type, content):
- z = zlib.compressobj(1)
+def _encode_looseobj(type, content, compression_level=1):
+ z = zlib.compressobj(compression_level)
yield z.compress('%s %d\0' % (type, len(content)))
yield z.compress(content)
yield z.flush()
def exists(self, hash, want_source=False):
"""Return nonempty if the object exists in this index."""
if hash and (self._idx_from_hash(hash) != None):
- return want_source and self.name or True
+ return want_source and os.path.basename(self.name) or True
return None
def __len__(self):
yield buffer(self.map, 8 + 256*4 + 20*i, 20)
-extract_bits = _helpers.extract_bits
-
-bloom_contains = _helpers.bloom_contains
-bloom_add = _helpers.bloom_add
-
-
-class ShaBloom:
- """Wrapper which contains data from multiple index files.
- """
- def __init__(self, filename, f=None, readwrite=False, expected=-1):
- self.name = filename
- self.rwfile = None
- self.map = None
- assert(filename.endswith('.bloom'))
- if readwrite:
- assert(expected > 0)
- self.rwfile = f = f or open(filename, 'r+b')
- f.seek(0)
-
- # Decide if we want to mmap() the pages as writable ('immediate'
- # write) or else map them privately for later writing back to
- # the file ('delayed' write). A bloom table's write access
- # pattern is such that we dirty almost all the pages after adding
- # very few entries. But the table is so big that dirtying
- # *all* the pages often exceeds Linux's default
- # /proc/sys/vm/dirty_ratio or /proc/sys/vm/dirty_background_ratio,
- # thus causing it to start flushing the table before we're
- # finished... even though there's more than enough space to
- # store the bloom table in RAM.
- #
- # To work around that behaviour, if we calculate that we'll
- # probably end up touching the whole table anyway (at least
- # one bit flipped per memory page), let's use a "private" mmap,
- # which defeats Linux's ability to flush it to disk. Then we'll
- # flush it as one big lump during close().
- pages = os.fstat(f.fileno()).st_size / 4096 * 5 # assume k=5
- self.delaywrite = expected > pages
- debug1('bloom: delaywrite=%r\n' % self.delaywrite)
- if self.delaywrite:
- self.map = mmap_readwrite_private(self.rwfile, close=False)
- else:
- self.map = mmap_readwrite(self.rwfile, close=False)
- else:
- self.rwfile = None
- f = f or open(filename, 'rb')
- self.map = mmap_read(f)
- got = str(self.map[0:4])
- if got != 'BLOM':
- log('Warning: invalid BLOM header (%r) in %r\n' % (got, filename))
- return self._init_failed()
- ver = struct.unpack('!I', self.map[4:8])[0]
- if ver < BLOOM_VERSION:
- log('Warning: ignoring old-style (v%d) bloom %r\n'
- % (ver, filename))
- return self._init_failed()
- if ver > BLOOM_VERSION:
- log('Warning: ignoring too-new (v%d) bloom %r\n'
- % (ver, filename))
- return self._init_failed()
-
- self.bits, self.k, self.entries = struct.unpack('!HHI', self.map[8:16])
- idxnamestr = str(self.map[16 + 2**self.bits:])
- if idxnamestr:
- self.idxnames = idxnamestr.split('\0')
- else:
- self.idxnames = []
-
- def _init_failed(self):
- if self.map:
- self.map = None
- if self.rwfile:
- self.rwfile.close()
- self.rwfile = None
- self.idxnames = []
- self.bits = self.entries = 0
-
- def valid(self):
- return self.map and self.bits
-
- def __del__(self):
- self.close()
-
- def close(self):
- if self.map and self.rwfile:
- debug2("bloom: closing with %d entries\n" % self.entries)
- self.map[12:16] = struct.pack('!I', self.entries)
- if self.delaywrite:
- self.rwfile.seek(0)
- self.rwfile.write(self.map)
- else:
- self.map.flush()
- self.rwfile.seek(16 + 2**self.bits)
- if self.idxnames:
- self.rwfile.write('\0'.join(self.idxnames))
- self._init_failed()
-
- def pfalse_positive(self, additional=0):
- n = self.entries + additional
- m = 8*2**self.bits
- k = self.k
- return 100*(1-math.exp(-k*float(n)/m))**k
-
- def add_idx(self, ix):
- """Add the object to the filter, return current pfalse_positive."""
- if not self.map: raise Exception, "Cannot add to closed bloom"
- self.entries += bloom_add(self.map, ix.shatable, self.bits, self.k)
- self.idxnames.append(os.path.basename(ix.name))
-
- def exists(self, sha):
- """Return nonempty if the object probably exists in the bloom filter."""
- global _total_searches, _total_steps
- _total_searches += 1
- if not self.map: return None
- found, steps = bloom_contains(self.map, str(sha), self.bits, self.k)
- _total_steps += steps
- return found
-
- @classmethod
- def create(cls, name, expected, delaywrite=None, f=None, k=None):
- """Create and return a bloom filter for `expected` entries."""
- bits = int(math.floor(math.log(expected*MAX_BITS_EACH/8,2)))
- k = k or ((bits <= MAX_BLOOM_BITS[5]) and 5 or 4)
- if bits > MAX_BLOOM_BITS[k]:
- log('bloom: warning, max bits exceeded, non-optimal\n')
- bits = MAX_BLOOM_BITS[k]
- debug1('bloom: using 2^%d bytes and %d hash functions\n' % (bits, k))
- f = f or open(name, 'w+b')
- f.write('BLOM')
- f.write(struct.pack('!IHHI', BLOOM_VERSION, bits, k, 0))
- assert(f.tell() == 16)
- # NOTE: On some systems this will not extend+zerofill, but it does on
- # darwin, linux, bsd and solaris.
- f.truncate(16+2**bits)
- f.seek(0)
- if delaywrite != None and not delaywrite:
- # tell it to expect very few objects, forcing a direct mmap
- expected = 1
- return cls(name, f=f, readwrite=True, expected=expected)
-
- def __len__(self):
- return self.entries
-
-
-class PackMidx:
- """Wrapper which contains data from multiple index files.
- Multiple index (.midx) files constitute a wrapper around index (.idx) files
- and make it possible for bup to expand Git's indexing capabilities to vast
- amounts of files.
- """
- def __init__(self, filename):
- self.name = filename
- self.force_keep = False
- assert(filename.endswith('.midx'))
- self.map = mmap_read(open(filename))
- if str(self.map[0:4]) != 'MIDX':
- log('Warning: skipping: invalid MIDX header in %r\n' % filename)
- self.force_keep = True
- return self._init_failed()
- ver = struct.unpack('!I', self.map[4:8])[0]
- if ver < MIDX_VERSION:
- log('Warning: ignoring old-style (v%d) midx %r\n'
- % (ver, filename))
- self.force_keep = False # old stuff is boring
- return self._init_failed()
- if ver > MIDX_VERSION:
- log('Warning: ignoring too-new (v%d) midx %r\n'
- % (ver, filename))
- self.force_keep = True # new stuff is exciting
- return self._init_failed()
-
- self.bits = _helpers.firstword(self.map[8:12])
- self.entries = 2**self.bits
- self.fanout = buffer(self.map, 12, self.entries*4)
- self.sha_ofs = 12 + self.entries*4
- self.nsha = nsha = self._fanget(self.entries-1)
- self.shatable = buffer(self.map, self.sha_ofs, nsha*20)
- self.whichlist = buffer(self.map, self.sha_ofs + nsha*20, nsha*4)
- self.idxname_ofs = self.sha_ofs + 24*nsha
- self.idxnames = str(self.map[self.idxname_ofs:]).split('\0')
-
- def _init_failed(self):
- self.bits = 0
- self.entries = 1
- self.fanout = buffer('\0\0\0\0')
- self.shatable = buffer('\0'*20)
- self.idxnames = []
-
- def _fanget(self, i):
- start = i*4
- s = self.fanout[start:start+4]
- return _helpers.firstword(s)
-
- def _get(self, i):
- return str(self.shatable[i*20:(i+1)*20])
-
- def _get_idx_i(self, i):
- return struct.unpack('!I', self.whichlist[i*4:(i+1)*4])[0]
-
- def _get_idxname(self, i):
- return self.idxnames[self._get_idx_i(i)]
-
- def exists(self, hash, want_source=False):
- """Return nonempty if the object exists in the index files."""
- global _total_searches, _total_steps
- _total_searches += 1
- want = str(hash)
- el = extract_bits(want, self.bits)
- if el:
- start = self._fanget(el-1)
- startv = el << (32-self.bits)
- else:
- start = 0
- startv = 0
- end = self._fanget(el)
- endv = (el+1) << (32-self.bits)
- _total_steps += 1 # lookup table is a step
- hashv = _helpers.firstword(hash)
- #print '(%08x) %08x %08x %08x' % (extract_bits(want, 32), startv, hashv, endv)
- while start < end:
- _total_steps += 1
- #print '! %08x %08x %08x %d - %d' % (startv, hashv, endv, start, end)
- mid = start + (hashv-startv)*(end-start-1)/(endv-startv)
- #print ' %08x %08x %08x %d %d %d' % (startv, hashv, endv, start, mid, end)
- v = self._get(mid)
- #print ' %08x' % self._num(v)
- if v < want:
- start = mid+1
- startv = _helpers.firstword(v)
- elif v > want:
- end = mid
- endv = _helpers.firstword(v)
- else: # got it!
- return want_source and self._get_idxname(mid) or True
- return None
-
- def __iter__(self):
- for i in xrange(self._fanget(self.entries-1)):
- yield buffer(self.shatable, i*20, 20)
-
- def __len__(self):
- return int(self._fanget(self.entries-1))
-
-
_mpi_count = 0
class PackIdxList:
def __init__(self, dir):
_total_searches += 1
if hash in self.also:
return True
- if self.do_bloom and self.bloom is not None:
- _total_searches -= 1 # will be incremented by bloom
+ if self.do_bloom and self.bloom:
if self.bloom.exists(hash):
self.do_bloom = False
else:
+ _total_searches -= 1 # was counted by bloom
return None
for i in xrange(len(self.packs)):
p = self.packs[i]
self.do_bloom = False
skip_midx = skip_midx or ignore_midx
d = dict((p.name, p) for p in self.packs
- if not skip_midx or not isinstance(p, PackMidx))
+ if not skip_midx or not isinstance(p, midx.PackMidx))
if os.path.exists(self.dir):
if not skip_midx:
midxl = []
for ix in self.packs:
- if isinstance(ix, PackMidx):
+ if isinstance(ix, midx.PackMidx):
for name in ix.idxnames:
d[os.path.join(self.dir, name)] = ix
for full in glob.glob(os.path.join(self.dir,'*.midx')):
if not d.get(full):
- mx = PackMidx(full)
+ mx = midx.PackMidx(full)
(mxd, mxf) = os.path.split(mx.name)
broken = False
for n in mx.idxnames:
' used by %s\n') % (n, mxf))
broken = True
if broken:
+ mx.close()
del mx
unlink(full)
else:
midxl.append(mx)
- midxl.sort(lambda x,y: -cmp(len(x),len(y)))
+ midxl.sort(key=lambda ix:
+ (-len(ix), -xstat.stat(ix.name).st_mtime))
for ix in midxl:
any_needed = False
for sub in ix.idxnames:
elif not ix.force_keep:
debug1('midx: removing redundant: %s\n'
% os.path.basename(ix.name))
+ ix.close()
unlink(ix.name)
for full in glob.glob(os.path.join(self.dir,'*.idx')):
if not d.get(full):
try:
ix = open_idx(full)
- except GitError, e:
+ except GitError as e:
add_error(e)
continue
d[full] = ix
bfull = os.path.join(self.dir, 'bup.bloom')
if self.bloom is None and os.path.exists(bfull):
- self.bloom = ShaBloom(bfull)
+ self.bloom = bloom.ShaBloom(bfull)
self.packs = list(set(d.values()))
self.packs.sort(lambda x,y: -cmp(len(x),len(y)))
if self.bloom and self.bloom.valid() and len(self.bloom) >= len(self):
self.also.add(hash)
-def calc_hash(type, content):
- """Calculate some content's hash in the Git fashion."""
- header = '%s %d\0' % (type, len(content))
- sum = Sha1(header)
- sum.update(content)
- return sum.digest()
-
-
-def _shalist_sort_key(ent):
- (mode, name, id) = ent
- if stat.S_ISDIR(int(mode, 8)):
- return name + '/'
- else:
- return name
-
-
def open_idx(filename):
if filename.endswith('.idx'):
f = open(filename, 'rb')
else:
raise GitError('%s: unrecognized idx file header' % filename)
elif filename.endswith('.midx'):
- return PackMidx(filename)
+ return midx.PackMidx(filename)
else:
raise GitError('idx filenames must end with .idx or .midx')
def idxmerge(idxlist, final_progress=True):
"""Generate a list of all the objects reachable in a PackIdxList."""
def pfunc(count, total):
- progress('Reading indexes: %.2f%% (%d/%d)\r'
- % (count*100.0/total, count, total))
+ qprogress('Reading indexes: %.2f%% (%d/%d)\r'
+ % (count*100.0/total, count, total))
def pfinal(count, total):
if final_progress:
- log('Reading indexes: %.2f%% (%d/%d), done.\n' % (100, total, total))
+ progress('Reading indexes: %.2f%% (%d/%d), done.\n'
+ % (100, total, total))
return merge_iter(idxlist, 10024, pfunc, pfinal)
def _make_objcache():
return PackIdxList(repo('objects/pack'))
+# bup-gc assumes that it can disable all PackWriter activities
+# (bloom/midx/cache) via the constructor and close() arguments.
+
class PackWriter:
- """Writes Git objects insid a pack file."""
- def __init__(self, objcache_maker=_make_objcache):
+ """Writes Git objects inside a pack file."""
+ def __init__(self, objcache_maker=_make_objcache, compression_level=1,
+ run_midx=True, on_pack_finish=None):
+ self.file = None
+ self.parentfd = None
self.count = 0
self.outbytes = 0
self.filename = None
- self.file = None
self.idx = None
self.objcache_maker = objcache_maker
self.objcache = None
+ self.compression_level = compression_level
+ self.run_midx=run_midx
+ self.on_pack_finish = on_pack_finish
def __del__(self):
self.close()
def _open(self):
if not self.file:
- (fd,name) = tempfile.mkstemp(suffix='.pack', dir=repo('objects'))
- self.file = os.fdopen(fd, 'w+b')
+ objdir = dir=repo('objects')
+ fd, name = tempfile.mkstemp(suffix='.pack', dir=objdir)
+ try:
+ self.file = os.fdopen(fd, 'w+b')
+ except:
+ os.close(fd)
+ raise
+ try:
+ self.parentfd = os.open(objdir, os.O_RDONLY)
+ except:
+ f = self.file
+ self.file = None
+ f.close()
+ raise
assert(name.endswith('.pack'))
self.filename = name[:-5]
self.file.write('PACK\0\0\0\2\0\0\0\0')
self.idx = list(list() for i in xrange(256))
- # the 'sha' parameter is used in client.py's _raw_write(), but not needed
- # in this basic version.
def _raw_write(self, datalist, sha):
self._open()
f = self.file
oneblob = ''.join(datalist)
try:
f.write(oneblob)
- except IOError, e:
+ except IOError as e:
raise GitError, e, sys.exc_info()[2]
nw = len(oneblob)
crc = zlib.crc32(oneblob) & 0xffffffff
log('>')
if not sha:
sha = calc_hash(type, content)
- size, crc = self._raw_write(_encode_packobj(type, content), sha=sha)
+ size, crc = self._raw_write(_encode_packobj(type, content,
+ self.compression_level),
+ sha=sha)
+ if self.outbytes >= max_pack_size or self.count >= max_pack_objects:
+ self.breakpoint()
return sha
def breakpoint(self):
"""Clear byte and object counts and return the last processed id."""
- id = self._end()
+ id = self._end(self.run_midx)
self.outbytes = self.count = 0
return id
self._require_objcache()
return self.objcache.exists(id, want_source=want_source)
+ def just_write(self, sha, type, content):
+ """Write an object to the pack file, bypassing the objcache. Fails if
+ sha exists()."""
+ self._write(sha, type, content)
+
def maybe_write(self, type, content):
"""Write an object to the pack file if not present and return its id."""
- self._require_objcache()
sha = calc_hash(type, content)
if not self.exists(sha):
- self._write(sha, type, content)
+ self.just_write(sha, type, content)
+ self._require_objcache()
self.objcache.add(sha)
return sha
def new_tree(self, shalist):
"""Create a tree object in the pack."""
- shalist = sorted(shalist, key = _shalist_sort_key)
- l = []
- for (mode,name,bin) in shalist:
- assert(mode)
- assert(mode != '0')
- assert(mode[0] != '0')
- assert(name)
- assert(len(bin) == 20)
- l.append('%s %s\0%s' % (mode,name,bin))
- return self.maybe_write('tree', ''.join(l))
-
- def _new_commit(self, tree, parent, author, adate, committer, cdate, msg):
+ content = tree_encode(shalist)
+ return self.maybe_write('tree', content)
+
+ def new_commit(self, tree, parent,
+ author, adate_sec, adate_tz,
+ committer, cdate_sec, cdate_tz,
+ msg):
+ """Create a commit object in the pack. The date_sec values must be
+ epoch-seconds, and if a tz is None, the local timezone is assumed."""
+ if adate_tz:
+ adate_str = _git_date_str(adate_sec, adate_tz)
+ else:
+ adate_str = _local_git_date_str(adate_sec)
+ if cdate_tz:
+ cdate_str = _git_date_str(cdate_sec, cdate_tz)
+ else:
+ cdate_str = _local_git_date_str(cdate_sec)
l = []
if tree: l.append('tree %s' % tree.encode('hex'))
if parent: l.append('parent %s' % parent.encode('hex'))
- if author: l.append('author %s %s' % (author, _git_date(adate)))
- if committer: l.append('committer %s %s' % (committer, _git_date(cdate)))
+ if author: l.append('author %s %s' % (author, adate_str))
+ if committer: l.append('committer %s %s' % (committer, cdate_str))
l.append('')
l.append(msg)
return self.maybe_write('commit', '\n'.join(l))
- def new_commit(self, parent, tree, date, msg):
- """Create a commit object in the pack."""
- userline = '%s <%s@%s>' % (userfullname(), username(), hostname())
- commit = self._new_commit(tree, parent,
- userline, date, userline, date,
- msg)
- return commit
-
def abort(self):
"""Remove the pack file from disk."""
f = self.file
if f:
- self.idx = None
+ pfd = self.parentfd
self.file = None
- f.close()
- os.unlink(self.filename + '.pack')
+ self.parentfd = None
+ self.idx = None
+ try:
+ try:
+ os.unlink(self.filename + '.pack')
+ finally:
+ f.close()
+ finally:
+ if pfd is not None:
+ os.close(pfd)
def _end(self, run_midx=True):
f = self.file
if not f: return None
self.file = None
- self.objcache = None
- idx = self.idx
- self.idx = None
+ try:
+ self.objcache = None
+ idx = self.idx
+ self.idx = None
- # update object count
- f.seek(8)
- cp = struct.pack('!i', self.count)
- assert(len(cp) == 4)
- f.write(cp)
-
- # calculate the pack sha1sum
- f.seek(0)
- sum = Sha1()
- for b in chunkyreader(f):
- sum.update(b)
- packbin = sum.digest()
- f.write(packbin)
- f.close()
-
- idx_f = open(self.filename + '.idx', 'wb')
- obj_list_sha = self._write_pack_idx_v2(idx_f, idx, packbin)
- idx_f.close()
+ # update object count
+ f.seek(8)
+ cp = struct.pack('!i', self.count)
+ assert(len(cp) == 4)
+ f.write(cp)
+
+ # calculate the pack sha1sum
+ f.seek(0)
+ sum = Sha1()
+ for b in chunkyreader(f):
+ sum.update(b)
+ packbin = sum.digest()
+ f.write(packbin)
+ fdatasync(f.fileno())
+ finally:
+ f.close()
+
+ obj_list_sha = self._write_pack_idx_v2(self.filename + '.idx', idx, packbin)
nameprefix = repo('objects/pack/pack-%s' % obj_list_sha)
if os.path.exists(self.filename + '.map'):
os.unlink(self.filename + '.map')
os.rename(self.filename + '.pack', nameprefix + '.pack')
os.rename(self.filename + '.idx', nameprefix + '.idx')
+ try:
+ os.fsync(self.parentfd)
+ finally:
+ os.close(self.parentfd)
if run_midx:
auto_midx(repo('objects/pack'))
+
+ if self.on_pack_finish:
+ self.on_pack_finish(nameprefix)
+
return nameprefix
def close(self, run_midx=True):
"""Close the pack file and move it to its definitive path."""
return self._end(run_midx=run_midx)
- def _write_pack_idx_v2(self, file, idx, packbin):
- sum = Sha1()
-
- def write(data):
- file.write(data)
- sum.update(data)
-
- write('\377tOc\0\0\0\2')
-
- n = 0
- for part in idx:
- n += len(part)
- write(struct.pack('!i', n))
- part.sort(key=lambda x: x[0])
-
- obj_list_sum = Sha1()
- for part in idx:
- for entry in part:
- write(entry[0])
- obj_list_sum.update(entry[0])
- for part in idx:
- for entry in part:
- write(struct.pack('!I', entry[1]))
- ofs64_list = []
- for part in idx:
- for entry in part:
- if entry[2] & 0x80000000:
- write(struct.pack('!I', 0x80000000 | len(ofs64_list)))
- ofs64_list.append(struct.pack('!Q', entry[2]))
- else:
- write(struct.pack('!i', entry[2]))
- for ofs64 in ofs64_list:
- write(ofs64)
-
- write(packbin)
- file.write(sum.digest())
- return obj_list_sum.hexdigest()
-
-
-def _git_date(date):
- return '%d %s' % (date, time.strftime('%z', time.localtime(date)))
-
-
-def _gitenv():
- os.environ['GIT_DIR'] = os.path.abspath(repo())
-
+ def _write_pack_idx_v2(self, filename, idx, packbin):
+ ofs64_count = 0
+ for section in idx:
+ for entry in section:
+ if entry[2] >= 2**31:
+ ofs64_count += 1
+
+ # Length: header + fan-out + shas-and-crcs + overflow-offsets
+ index_len = 8 + (4 * 256) + (28 * self.count) + (8 * ofs64_count)
+ idx_map = None
+ idx_f = open(filename, 'w+b')
+ try:
+ idx_f.truncate(index_len)
+ fdatasync(idx_f.fileno())
+ idx_map = mmap_readwrite(idx_f, close=False)
+ try:
+ count = _helpers.write_idx(filename, idx_map, idx, self.count)
+ assert(count == self.count)
+ idx_map.flush()
+ finally:
+ idx_map.close()
+ finally:
+ idx_f.close()
+
+ idx_f = open(filename, 'a+b')
+ try:
+ idx_f.write(packbin)
+ idx_f.seek(0)
+ idx_sum = Sha1()
+ b = idx_f.read(8 + 4*256)
+ idx_sum.update(b)
+
+ obj_list_sum = Sha1()
+ for b in chunkyreader(idx_f, 20*self.count):
+ idx_sum.update(b)
+ obj_list_sum.update(b)
+ namebase = obj_list_sum.hexdigest()
+
+ for b in chunkyreader(idx_f):
+ idx_sum.update(b)
+ idx_f.write(idx_sum.digest())
+ fdatasync(idx_f.fileno())
+ return namebase
+ finally:
+ idx_f.close()
+
+
+def _gitenv(repo_dir = None):
+ if not repo_dir:
+ repo_dir = repo()
+ def env():
+ os.environ['GIT_DIR'] = os.path.abspath(repo_dir)
+ return env
+
+
+def list_refs(refnames=None, repo_dir=None,
+ limit_to_heads=False, limit_to_tags=False):
+ """Yield (refname, hash) tuples for all repository refs unless
+ refnames are specified. In that case, only include tuples for
+ those refs. The limits restrict the result items to refs/heads or
+ refs/tags. If both limits are specified, items from both sources
+ will be included.
-def list_refs(refname = None):
- """Generate a list of tuples in the form (refname,hash).
- If a ref name is specified, list only this particular ref.
"""
- argv = ['git', 'show-ref', '--']
- if refname:
- argv += [refname]
- p = subprocess.Popen(argv, preexec_fn = _gitenv, stdout = subprocess.PIPE)
+ argv = ['git', 'show-ref']
+ if limit_to_heads:
+ argv.append('--heads')
+ if limit_to_tags:
+ argv.append('--tags')
+ argv.append('--')
+ if refnames:
+ argv += refnames
+ p = subprocess.Popen(argv,
+ preexec_fn = _gitenv(repo_dir),
+ stdout = subprocess.PIPE)
out = p.stdout.read().strip()
rv = p.wait() # not fatal
if rv:
yield (name, sha.decode('hex'))
-def read_ref(refname):
+def read_ref(refname, repo_dir = None):
"""Get the commit id of the most recent commit made on a given ref."""
- l = list(list_refs(refname))
+ refs = list_refs(refnames=[refname], repo_dir=repo_dir, limit_to_heads=True)
+ l = tuple(islice(refs, 2))
if l:
assert(len(l) == 1)
return l[0][1]
return None
-def rev_list(ref, count=None):
+def rev_list(ref, count=None, repo_dir=None):
"""Generate a list of reachable commits in reverse chronological order.
This generator walks through commits, from child to parent, that are
opts = []
if count:
opts += ['-n', str(atoi(count))]
- argv = ['git', 'rev-list', '--pretty=format:%ct'] + opts + [ref, '--']
- p = subprocess.Popen(argv, preexec_fn = _gitenv, stdout = subprocess.PIPE)
+ argv = ['git', 'rev-list', '--pretty=format:%at'] + opts + [ref, '--']
+ p = subprocess.Popen(argv,
+ preexec_fn = _gitenv(repo_dir),
+ stdout = subprocess.PIPE)
commit = None
for row in p.stdout:
s = row.strip()
raise GitError, 'git rev-list returned error %d' % rv
-def rev_get_date(ref):
- """Get the date of the latest commit on the specified ref."""
- for (date, commit) in rev_list(ref, count=1):
- return date
- raise GitError, 'no such commit %r' % ref
+def get_commit_dates(refs, repo_dir=None):
+ """Get the dates for the specified commit refs. For now, every unique
+ string in refs must resolve to a different commit or this
+ function will fail."""
+ result = []
+ for ref in refs:
+ commit = get_commit_items(ref, cp(repo_dir))
+ result.append(commit.author_sec)
+ return result
-def rev_parse(committish):
+def rev_parse(committish, repo_dir=None):
"""Resolve the full hash for 'committish', if it exists.
Should be roughly equivalent to 'git rev-parse'.
Returns the hex value of the hash if it is found, None if 'committish' does
not correspond to anything.
"""
- head = read_ref(committish)
+ head = read_ref(committish, repo_dir=repo_dir)
if head:
debug2("resolved from ref: commit = %s\n" % head.encode('hex'))
return head
- pL = PackIdxList(repo('objects/pack'))
+ pL = PackIdxList(repo('objects/pack', repo_dir=repo_dir))
if len(committish) == 40:
try:
return None
-def update_ref(refname, newval, oldval):
- """Change the commit pointed to by a branch."""
+def update_ref(refname, newval, oldval, repo_dir=None):
+ """Update a repository reference."""
if not oldval:
oldval = ''
- assert(refname.startswith('refs/heads/'))
+ assert(refname.startswith('refs/heads/') \
+ or refname.startswith('refs/tags/'))
p = subprocess.Popen(['git', 'update-ref', refname,
newval.encode('hex'), oldval.encode('hex')],
- preexec_fn = _gitenv)
+ preexec_fn = _gitenv(repo_dir))
+ _git_wait('git update-ref', p)
+
+
+def delete_ref(refname, oldvalue=None):
+ """Delete a repository reference (see git update-ref(1))."""
+ assert(refname.startswith('refs/'))
+ oldvalue = [] if not oldvalue else [oldvalue]
+ p = subprocess.Popen(['git', 'update-ref', '-d', refname] + oldvalue,
+ preexec_fn = _gitenv())
_git_wait('git update-ref', p)
if parent and not os.path.exists(parent):
raise GitError('parent directory "%s" does not exist\n' % parent)
if os.path.exists(d) and not os.path.isdir(os.path.join(d, '.')):
- raise GitError('"%d" exists but is not a directory\n' % d)
+ raise GitError('"%s" exists but is not a directory\n' % d)
p = subprocess.Popen(['git', '--bare', 'init'], stdout=sys.stderr,
- preexec_fn = _gitenv)
+ preexec_fn = _gitenv())
_git_wait('git init', p)
# Force the index version configuration in order to ensure bup works
# regardless of the version of the installed Git binary.
p = subprocess.Popen(['git', 'config', 'pack.indexVersion', '2'],
- stdout=sys.stderr, preexec_fn = _gitenv)
+ stdout=sys.stderr, preexec_fn = _gitenv())
+ _git_wait('git config', p)
+ # Enable the reflog
+ p = subprocess.Popen(['git', 'config', 'core.logAllRefUpdates', 'true'],
+ stdout=sys.stderr, preexec_fn = _gitenv())
_git_wait('git config', p)
def check_repo_or_die(path=None):
- """Make sure a bup repository exists, and abort if not.
- If the path to a particular repository was not specified, this function
- initializes the default repository automatically.
- """
+ """Check to see if a bup repository probably exists, and abort if not."""
guess_repo(path)
- if not os.path.isdir(repo('objects/pack/.')):
- if repodir == home_repodir:
- init_repo()
- else:
- log('error: %r is not a bup/git repository\n' % repo())
+ top = repo()
+ pst = stat_if_exists(top + '/objects/pack')
+ if pst and stat.S_ISDIR(pst.st_mode):
+ return
+ if not pst:
+ top_st = stat_if_exists(top)
+ if not top_st:
+ log('error: repository %r does not exist (see "bup help init")\n'
+ % top)
sys.exit(15)
-
-
-def treeparse(buf):
- """Generate a list of (mode, name, hash) tuples of objects from 'buf'."""
- ofs = 0
- while ofs < len(buf):
- z = buf[ofs:].find('\0')
- assert(z > 0)
- spl = buf[ofs:ofs+z].split(' ', 1)
- assert(len(spl) == 2)
- sha = buf[ofs+z+1:ofs+z+1+20]
- ofs += z+1+20
- yield (spl[0], spl[1], sha)
+ log('error: %r is not a repository\n' % top)
+ sys.exit(14)
_ver = None
def _git_capture(argv):
- p = subprocess.Popen(argv, stdout=subprocess.PIPE, preexec_fn = _gitenv)
+ p = subprocess.Popen(argv, stdout=subprocess.PIPE, preexec_fn = _gitenv())
r = p.stdout.read()
_git_wait(repr(argv), p)
return r
def next(self):
try:
return self.it.next()
- except StopIteration, e:
+ except StopIteration as e:
self.done = True
raise
except:
self.abort()
+class MissingObject(KeyError):
+ def __init__(self, id):
+ self.id = id
+ KeyError.__init__(self, 'object %r is missing' % id.encode('hex'))
+
+
_ver_warned = 0
class CatPipe:
"""Link to 'git cat-file' that is used to retrieve blob data."""
- def __init__(self):
+ def __init__(self, repo_dir = None):
global _ver_warned
+ self.repo_dir = repo_dir
wanted = ('1','5','6')
if ver() < wanted:
if not _ver_warned:
self.p = None
self.inprogress = None
- def _restart(self):
+ def restart(self):
self._abort()
self.p = subprocess.Popen(['git', 'cat-file', '--batch'],
stdin=subprocess.PIPE,
stdout=subprocess.PIPE,
close_fds = True,
bufsize = 4096,
- preexec_fn = _gitenv)
+ preexec_fn = _gitenv(self.repo_dir))
def _fast_get(self, id):
if not self.p or self.p.poll() != None:
- self._restart()
+ self.restart()
assert(self.p)
- assert(self.p.poll() == None)
+ poll_result = self.p.poll()
+ assert(poll_result == None)
if self.inprogress:
- log('_fast_get: opening %r while %r is open'
+ log('_fast_get: opening %r while %r is open\n'
% (id, self.inprogress))
assert(not self.inprogress)
assert(id.find('\n') < 0)
hdr = self.p.stdout.readline()
if hdr.endswith(' missing\n'):
self.inprogress = None
- raise KeyError('blob %r is missing' % id)
+ raise MissingObject(id.decode('hex'))
spl = hdr.split(' ')
if len(spl) != 3 or len(spl[0]) != 40:
raise GitError('expected blob, got %r' % spl)
yield type
for blob in it:
yield blob
- assert(self.p.stdout.readline() == '\n')
+ readline_result = self.p.stdout.readline()
+ assert(readline_result == '\n')
self.inprogress = None
- except Exception, e:
+ except Exception as e:
it.abort()
raise
p = subprocess.Popen(['git', 'cat-file', type, id],
stdout=subprocess.PIPE,
- preexec_fn = _gitenv)
+ preexec_fn = _gitenv(self.repo_dir))
for blob in chunkyreader(p.stdout):
yield blob
_git_wait('git cat-file', p)
yield blob
elif type == 'tree':
treefile = ''.join(it)
- for (mode, name, sha) in treeparse(treefile):
+ for (mode, name, sha) in tree_decode(treefile):
for blob in self.join(sha.encode('hex')):
yield blob
elif type == 'commit':
except StopIteration:
log('booger!\n')
-def tags():
+
+_cp = {}
+
+def cp(repo_dir=None):
+ """Create a CatPipe object or reuse the already existing one."""
+ global _cp
+ if not repo_dir:
+ repo_dir = repo()
+ repo_dir = os.path.abspath(repo_dir)
+ cp = _cp.get(repo_dir)
+ if not cp:
+ cp = CatPipe(repo_dir)
+ _cp[repo_dir] = cp
+ return cp
+
+
+def tags(repo_dir = None):
"""Return a dictionary of all tags in the form {hash: [tag_names, ...]}."""
tags = {}
- for (n,c) in list_refs():
- if n.startswith('refs/tags/'):
- name = n[10:]
- if not c in tags:
- tags[c] = []
+ for n, c in list_refs(repo_dir = repo_dir, limit_to_tags=True):
+ assert(n.startswith('refs/tags/'))
+ name = n[10:]
+ if not c in tags:
+ tags[c] = []
+ tags[c].append(name) # more than one tag can point at 'c'
+ return tags
- tags[c].append(name) # more than one tag can point at 'c'
- return tags
+WalkItem = namedtuple('WalkItem', ['id', 'type', 'mode',
+ 'path', 'chunk_path', 'data'])
+# The path is the mangled path, and if an item represents a fragment
+# of a chunked file, the chunk_path will be the chunked subtree path
+# for the chunk, i.e. ['', '2d3115e', ...]. The top-level path for a
+# chunked file will have a chunk_path of ['']. So some chunk subtree
+# of the file '/foo/bar/baz' might look like this:
+#
+# item.path = ['foo', 'bar', 'baz.bup']
+# item.chunk_path = ['', '2d3115e', '016b097']
+# item.type = 'tree'
+# ...
+
+
+def walk_object(cat_pipe, id,
+ stop_at=None,
+ include_data=None):
+ """Yield everything reachable from id via cat_pipe as a WalkItem,
+ stopping whenever stop_at(id) returns true. Throw MissingObject
+ if a hash encountered is missing from the repository, and don't
+ read or return blob content in the data field unless include_data
+ is set.
+ """
+ # Maintain the pending stack on the heap to avoid stack overflow
+ pending = [(id, [], [], None)]
+ while len(pending):
+ id, parent_path, chunk_path, mode = pending.pop()
+ if stop_at and stop_at(id):
+ continue
+
+ if (not include_data) and mode and stat.S_ISREG(mode):
+ # If the object is a "regular file", then it's a leaf in
+ # the graph, so we can skip reading the data if the caller
+ # hasn't requested it.
+ yield WalkItem(id=id, type='blob',
+ chunk_path=chunk_path, path=parent_path,
+ mode=mode,
+ data=None)
+ continue
+
+ item_it = cat_pipe.get(id)
+ type = item_it.next()
+ if type not in ('blob', 'commit', 'tree'):
+ raise Exception('unexpected repository object type %r' % type)
+
+ # FIXME: set the mode based on the type when the mode is None
+ if type == 'blob' and not include_data:
+ # Dump data until we can ask cat_pipe not to fetch it
+ for ignored in item_it:
+ pass
+ data = None
+ else:
+ data = ''.join(item_it)
+
+ yield WalkItem(id=id, type=type,
+ chunk_path=chunk_path, path=parent_path,
+ mode=mode,
+ data=(data if include_data else None))
+
+ if type == 'commit':
+ commit_items = parse_commit(data)
+ for pid in commit_items.parents:
+ pending.append((pid, parent_path, chunk_path, mode))
+ pending.append((commit_items.tree, parent_path, chunk_path,
+ hashsplit.GIT_MODE_TREE))
+ elif type == 'tree':
+ for mode, name, ent_id in tree_decode(data):
+ demangled, bup_type = demangle_name(name, mode)
+ if chunk_path:
+ sub_path = parent_path
+ sub_chunk_path = chunk_path + [name]
+ else:
+ sub_path = parent_path + [name]
+ if bup_type == BUP_CHUNKED:
+ sub_chunk_path = ['']
+ else:
+ sub_chunk_path = chunk_path
+ pending.append((ent_id.encode('hex'), sub_path, sub_chunk_path,
+ mode))