-import os, errno, zlib, time, sha, subprocess
+import os, errno, zlib, time, sha, subprocess, struct, mmap, stat, re
from helpers import *
+verbose = 0
+home_repodir = os.path.expanduser('~/.bup')
+repodir = None
-def hash_raw(type, s):
- header = '%s %d\0' % (type, len(s))
+
+class GitError(Exception):
+ pass
+
+
+def repo(sub = ''):
+ global repodir
+ if not repodir:
+ raise GitError('You should call check_repo_or_die()')
+ gd = os.path.join(repodir, '.git')
+ if os.path.exists(gd):
+ repodir = gd
+ return os.path.join(repodir, sub)
+
+
+class PackIndex:
+ def __init__(self, filename):
+ self.name = filename
+ f = open(filename)
+ self.map = mmap.mmap(f.fileno(), 0,
+ mmap.MAP_SHARED, mmap.PROT_READ)
+ f.close() # map will persist beyond file close
+ assert(str(self.map[0:8]) == '\377tOc\0\0\0\2')
+ self.fanout = list(struct.unpack('!256I',
+ str(buffer(self.map, 8, 256*4))))
+ self.fanout.append(0) # entry "-1"
+ nsha = self.fanout[255]
+ self.ofstable = buffer(self.map,
+ 8 + 256*4 + nsha*20 + nsha*4,
+ nsha*4)
+ self.ofs64table = buffer(self.map,
+ 8 + 256*4 + nsha*20 + nsha*4 + nsha*4)
+
+ def _ofs_from_idx(self, idx):
+ ofs = struct.unpack('!I', str(buffer(self.ofstable, idx*4, 4)))[0]
+ if ofs & 0x80000000:
+ idx64 = ofs & 0x7fffffff
+ ofs = struct.unpack('!I',
+ str(buffer(self.ofs64table, idx64*8, 8)))[0]
+ return ofs
+
+ def _idx_from_hash(self, hash):
+ assert(len(hash) == 20)
+ b1 = ord(hash[0])
+ start = self.fanout[b1-1] # range -1..254
+ end = self.fanout[b1] # range 0..255
+ buf = buffer(self.map, 8 + 256*4, end*20)
+ want = buffer(hash)
+ while start < end:
+ mid = start + (end-start)/2
+ v = buffer(buf, mid*20, 20)
+ if v < want:
+ start = mid+1
+ elif v > want:
+ end = mid
+ else: # got it!
+ return mid
+ return None
+
+ def find_offset(self, hash):
+ idx = self._idx_from_hash(hash)
+ if idx != None:
+ return self._ofs_from_idx(idx)
+ return None
+
+ def exists(self, hash):
+ return (self._idx_from_hash(hash) != None) and True or None
+
+
+class MultiPackIndex:
+ def __init__(self, dir):
+ self.dir = dir
+ self.also = {}
+ self.packs = []
+ for f in os.listdir(self.dir):
+ if f.endswith('.idx'):
+ self.packs.append(PackIndex(os.path.join(self.dir, f)))
+
+ def exists(self, hash):
+ if hash in self.also:
+ return True
+ for i in range(len(self.packs)):
+ p = self.packs[i]
+ if p.exists(hash):
+ # reorder so most recently used packs are searched first
+ self.packs = [p] + self.packs[:i] + self.packs[i+1:]
+ return True
+ return None
+
+ def add(self, hash):
+ self.also[hash] = 1
+
+ def zap_also(self):
+ self.also = {}
+
+
+def calc_hash(type, content):
+ header = '%s %d\0' % (type, len(content))
sum = sha.sha(header)
- sum.update(s)
- hex = sum.hexdigest()
- dir = '.git/objects/%s' % hex[0:2]
- fn = '%s/%s' % (dir, hex[2:])
- if not os.path.exists(fn):
- #log('creating %s' % fn)
- try:
- os.mkdir(dir)
- except OSError, e:
- if e.errno != errno.EEXIST:
- raise
- tfn = '%s.%d' % (fn, os.getpid())
- f = open(tfn, 'w')
- z = zlib.compressobj(1)
- f.write(z.compress(header))
- f.write(z.compress(s))
- f.write(z.flush())
- f.close()
- os.rename(tfn, fn)
+ 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:
- #log('exists %s' % fn)
- pass
- return hex
+ return name
+
+
+_typemap = dict(blob=3, tree=2, commit=1, tag=8)
+class PackWriter:
+ def __init__(self, objcache_maker=None):
+ self.count = 0
+ self.outbytes = 0
+ self.filename = None
+ self.file = None
+ self.objcache_maker = objcache_maker
+ self.objcache = None
+
+ def __del__(self):
+ self.close()
+
+ def _make_objcache(self):
+ if not self.objcache:
+ if self.objcache_maker:
+ self.objcache = self.objcache_maker()
+ else:
+ self.objcache = MultiPackIndex(repo('objects/pack'))
+
+ def _open(self):
+ if not self.file:
+ self._make_objcache()
+ self.filename = repo('objects/bup%d' % os.getpid())
+ self.file = open(self.filename + '.pack', 'w+')
+ self.file.write('PACK\0\0\0\2\0\0\0\0')
+
+ def _raw_write(self, datalist):
+ self._open()
+ f = self.file
+ for d in datalist:
+ f.write(d)
+ self.outbytes += len(d)
+ self.count += 1
+
+ def _write(self, bin, type, content):
+ if verbose:
+ log('>')
+
+ out = []
+
+ sz = len(content)
+ szbits = (sz & 0x0f) | (_typemap[type]<<4)
+ sz >>= 4
+ while 1:
+ if sz: szbits |= 0x80
+ out.append(chr(szbits))
+ if not sz:
+ break
+ szbits = sz & 0x7f
+ sz >>= 7
+
+ z = zlib.compressobj(1)
+ out.append(z.compress(content))
+ out.append(z.flush())
+ self._raw_write(out)
+ return bin
-def hash_blob(blob):
- return hash_raw('blob', blob)
+ def breakpoint(self):
+ id = self._end()
+ self.outbytes = self.count = 0
+ return id
+ def write(self, type, content):
+ return self._write(calc_hash(type, content), type, content)
-def gen_tree(shalist):
- shalist = sorted(shalist, key = lambda x: x[1])
- l = ['%s %s\0%s' % (mode,name,hex.decode('hex'))
- for (mode,name,hex) in shalist]
- return hash_raw('tree', ''.join(l))
+ def maybe_write(self, type, content):
+ bin = calc_hash(type, content)
+ if not self.objcache:
+ self._make_objcache()
+ if not self.objcache.exists(bin):
+ self._write(bin, type, content)
+ self.objcache.add(bin)
+ return bin
+
+ def new_blob(self, blob):
+ return self.maybe_write('blob', blob)
+
+ def new_tree(self, shalist):
+ shalist = sorted(shalist, key = _shalist_sort_key)
+ l = ['%s %s\0%s' % (mode,name,bin)
+ for (mode,name,bin) in shalist]
+ return self.maybe_write('tree', ''.join(l))
+
+ def _new_commit(self, tree, parent, author, adate, committer, cdate, msg):
+ 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)))
+ l.append('')
+ l.append(msg)
+ return self.maybe_write('commit', '\n'.join(l))
+
+ def new_commit(self, parent, tree, msg):
+ now = time.time()
+ userline = '%s <%s@%s>' % (userfullname(), username(), hostname())
+ commit = self._new_commit(tree, parent,
+ userline, now, userline, now,
+ msg)
+ return commit
+
+ def abort(self):
+ f = self.file
+ if f:
+ self.file = None
+ f.close()
+ os.unlink(self.filename + '.pack')
+
+ def _end(self):
+ f = self.file
+ if not f: return None
+ self.file = 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 = sha.sha()
+ while 1:
+ b = f.read(65536)
+ sum.update(b)
+ if not b: break
+ f.write(sum.digest())
+
+ f.close()
+ self.objcache = None
+
+ p = subprocess.Popen(['git', 'index-pack', '-v',
+ '--index-version=2',
+ self.filename + '.pack'],
+ preexec_fn = _gitenv,
+ stdout = subprocess.PIPE)
+ out = p.stdout.read().strip()
+ _git_wait('git index-pack', p)
+ if not out:
+ raise GitError('git index-pack produced no output')
+ nameprefix = repo('objects/pack/%s' % out)
+ os.rename(self.filename + '.pack', nameprefix + '.pack')
+ os.rename(self.filename + '.idx', nameprefix + '.idx')
+ return nameprefix
+
+ def close(self):
+ return self._end()
def _git_date(date):
return time.strftime('%s %z', time.localtime(date))
-def _gitenv(repo):
- os.environ['GIT_DIR'] = os.path.abspath(repo)
+def _gitenv():
+ os.environ['GIT_DIR'] = os.path.abspath(repo())
-def _read_ref(repo, refname):
+def read_ref(refname):
p = subprocess.Popen(['git', 'show-ref', '--', refname],
- preexec_fn = lambda: _gitenv(repo),
+ preexec_fn = _gitenv,
stdout = subprocess.PIPE)
out = p.stdout.read().strip()
- p.wait()
+ rv = p.wait() # not fatal
+ if rv:
+ assert(not out)
if out:
- return out.split()[0]
+ return out.split()[0].decode('hex')
else:
return None
-def _update_ref(repo, refname, newval, oldval):
+def update_ref(refname, newval, oldval):
if not oldval:
oldval = ''
- p = subprocess.Popen(['git', 'update-ref', '--', refname, newval, oldval],
- preexec_fn = lambda: _gitenv(repo))
- p.wait()
- return newval
-
-
-def gen_commit(tree, parent, author, adate, committer, cdate, msg):
- l = []
- if tree: l.append('tree %s' % tree)
- if parent: l.append('parent %s' % parent)
- if author: l.append('author %s %s' % (author, _git_date(adate)))
- if committer: l.append('committer %s %s' % (committer, _git_date(cdate)))
- l.append('')
- l.append(msg)
- return hash_raw('commit', '\n'.join(l))
-
-
-def gen_commit_easy(ref, tree, msg):
- now = time.time()
- userline = '%s <%s@%s>' % (userfullname(), username(), hostname())
- oldref = ref and _read_ref('.git', ref) or None
- commit = gen_commit(tree, oldref, userline, now, userline, now, msg)
- if ref:
- _update_ref('.git', ref, commit, oldref)
- return commit
+ p = subprocess.Popen(['git', 'update-ref', '--', refname,
+ newval.encode('hex'), oldval.encode('hex')],
+ preexec_fn = _gitenv)
+ _git_wait('git update-ref', p)
+
+
+def guess_repo(path=None):
+ global repodir
+ if path:
+ repodir = path
+ if not repodir:
+ repodir = os.environ.get('BUP_DIR')
+ if not repodir:
+ repodir = os.path.expanduser('~/.bup')
+
+
+def init_repo(path=None):
+ guess_repo(path)
+ d = repo()
+ 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)
+ p = subprocess.Popen(['git', '--bare', 'init'], stdout=sys.stderr,
+ preexec_fn = _gitenv)
+ _git_wait('git init', p)
+ p = subprocess.Popen(['git', 'config', 'pack.indexVersion', '2'],
+ stdout=sys.stderr, preexec_fn = _gitenv)
+ _git_wait('git config', p)
+
+
+def check_repo_or_die(path=None):
+ 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())
+ exit(15)
+
+
+def _treeparse(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)
+
+_ver = None
+def ver():
+ global _ver
+ if not _ver:
+ p = subprocess.Popen(['git', '--version'],
+ stdout=subprocess.PIPE)
+ gvs = p.stdout.read()
+ _git_wait('git --version', p)
+ m = re.match(r'git version (\S+.\S+)', gvs)
+ if not m:
+ raise GitError('git --version weird output: %r' % gvs)
+ _ver = tuple(m.group(1).split('.'))
+ needed = ('1','5','4')
+ if _ver < needed:
+ raise GitError('git version %s or higher is required; you have %s'
+ % ('.'.join(needed), '.'.join(_ver)))
+ return _ver
+
+
+def _git_wait(cmd, p):
+ rv = p.wait()
+ if rv != 0:
+ raise GitError('%s returned %d' % (cmd, rv))
+
+
+def _git_capture(argv):
+ p = subprocess.Popen(argv, stdout=subprocess.PIPE, preexec_fn = _gitenv)
+ r = p.stdout.read()
+ _git_wait(repr(argv), p)
+ return r
+
+
+_ver_warned = 0
+class CatPipe:
+ def __init__(self):
+ global _ver_warned
+ wanted = ('1','5','6')
+ if ver() < wanted:
+ if not _ver_warned:
+ log('warning: git version < %s; bup will be slow.\n'
+ % '.'.join(wanted))
+ _ver_warned = 1
+ self.get = self._slow_get
+ else:
+ self.p = subprocess.Popen(['git', 'cat-file', '--batch'],
+ stdin=subprocess.PIPE,
+ stdout=subprocess.PIPE,
+ preexec_fn = _gitenv)
+ self.get = self._fast_get
+
+ def _fast_get(self, id):
+ assert(id.find('\n') < 0)
+ assert(id.find('\r') < 0)
+ assert(id[0] != '-')
+ self.p.stdin.write('%s\n' % id)
+ hdr = self.p.stdout.readline()
+ if hdr.endswith(' missing\n'):
+ raise GitError('blob %r is missing' % id)
+ spl = hdr.split(' ')
+ if len(spl) != 3 or len(spl[0]) != 40:
+ raise GitError('expected blob, got %r' % spl)
+ (hex, type, size) = spl
+ yield type
+ for blob in chunkyreader(self.p.stdout, int(spl[2])):
+ yield blob
+ assert(self.p.stdout.readline() == '\n')
+
+ def _slow_get(self, id):
+ assert(id.find('\n') < 0)
+ assert(id.find('\r') < 0)
+ assert(id[0] != '-')
+ type = _git_capture(['git', 'cat-file', '-t', id]).strip()
+ yield type
+
+ p = subprocess.Popen(['git', 'cat-file', type, id],
+ stdout=subprocess.PIPE,
+ preexec_fn = _gitenv)
+ for blob in chunkyreader(p.stdout):
+ yield blob
+ _git_wait('git cat-file', p)
+
+ def _join(self, it):
+ type = it.next()
+ if type == 'blob':
+ for blob in it:
+ yield blob
+ elif type == 'tree':
+ treefile = ''.join(it)
+ for (mode, name, sha) in _treeparse(treefile):
+ for blob in self.join(sha.encode('hex')):
+ yield blob
+ elif type == 'commit':
+ treeline = ''.join(it).split('\n')[0]
+ assert(treeline.startswith('tree '))
+ for blob in self.join(treeline[5:]):
+ yield blob
+ else:
+ raise GitError('invalid object type %r: expected blob/tree/commit'
+ % type)
+
+ def join(self, id):
+ for d in self._join(self.get(id)):
+ yield d
+
+
+def cat(id):
+ c = CatPipe()
+ for d in c.join(id):
+ yield d
projects / bup.git / blobdiff