1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
|
# Copyright (C) 2010 Jelmer Vernooij <jelmer@samba.org>
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
"""A Git repository implementation that uses a Bazaar transport."""
from dulwich.errors import (
NotGitRepository,
)
from dulwich.objects import (
ShaFile,
)
from dulwich.object_store import (
PackBasedObjectStore,
PACKDIR,
)
from dulwich.pack import (
Pack,
)
from dulwich.repo import (
BaseRepo,
RefsContainer,
OBJECTDIR,
REFSDIR,
BASE_DIRECTORIES,
SYMREF,
check_ref_format,
read_packed_refs_with_peeled,
read_packed_refs,
write_packed_refs,
)
from bzrlib import (
urlutils,
)
from bzrlib.errors import (
NoSuchFile,
)
class TransportRepo(BaseRepo):
def __init__(self, transport):
self.transport = transport
if self.transport.has(urlutils.join(".git", OBJECTDIR)):
self.bare = False
self._controltransport = self.transport.clone('.git')
elif (self.transport.has(OBJECTDIR) and
self.transport.has(REFSDIR)):
self.bare = True
self._controltransport = self.transport
else:
raise NotGitRepository(self.transport)
object_store = TransportObjectStore(
self._controltransport.clone(OBJECTDIR))
refs = TransportRefsContainer(self._controltransport)
super(TransportRepo, self).__init__(object_store, refs)
def get_named_file(self, path):
"""Get a file from the control dir with a specific name.
Although the filename should be interpreted as a filename relative to
the control dir in a disk-baked Repo, the object returned need not be
pointing to a file in that location.
:param path: The path to the file, relative to the control dir.
:return: An open file object, or None if the file does not exist.
"""
try:
return self._controltransport.get(path.lstrip('/'))
except NoSuchFile:
return None
def put_named_file(self, path, contents):
self._controltransport.put_bytes(path.lstrip('/'), contents)
def open_index(self):
"""Open the index for this repository."""
from dulwich.index import Index
return Index(self._controltransport.local_abspath('index'))
def __repr__(self):
return "<TransportRepo for %r>" % self.transport
@classmethod
def init(cls, transport, mkdir=True):
transport.mkdir('.git')
controltransport = transport.clone('.git')
cls.init_bare(controltransport)
return cls(controltransport)
@classmethod
def init_bare(cls, transport, mkdir=True):
for d in BASE_DIRECTORIES:
transport.mkdir(urlutils.join(*d))
ret = cls(transport)
ret.refs.set_ref("HEAD", "refs/heads/master")
ret.put_named_file('description', "Unnamed repository")
ret.put_named_file('config', """[core]
repositoryformatversion = 0
filemode = true
bare = false
logallrefupdates = true
""")
ret.put_named_file('info/excludes', '')
return ret
create = init_bare
class TransportObjectStore(PackBasedObjectStore):
"""Git-style object store that exists on disk."""
def __init__(self, transport):
"""Open an object store.
:param transport: Transport to open data from
"""
super(TransportObjectStore, self).__init__()
self.transport = transport
self.pack_transport = self.transport.clone(PACKDIR)
def _load_packs(self):
pack_files = []
for name in self.pack_transport.list_dir('.'):
# TODO: verify that idx exists first
if name.startswith("pack-") and name.endswith(".pack"):
# TODO: if stat fails, just use None - after all
# the st_mtime is just used for sorting
pack_files.append((self.pack_transport.stat(name).st_mtime, name))
pack_files.sort(reverse=True)
suffix_len = len(".pack")
return [Pack(self.pack_transport.get(f)[:-suffix_len]) for _, f in pack_files]
def _iter_loose_objects(self):
for base in self.transport.list_dir('.'):
if len(base) != 2:
continue
for rest in self.transport.list_dir(base):
yield base+rest
def _split_loose_object(self, sha):
return (sha[:2], sha[2:])
def _get_loose_object(self, sha):
path = '%s/%s' % self._split_loose_object(sha)
try:
return ShaFile.from_file(self.transport.get(path))
except NoSuchFile:
return None
def add_object(self, obj):
"""Add a single object to this object store.
:param obj: Object to add
"""
(dir, file) = self._split_loose_object(obj.id)
self.transport.mkdir(dir)
path = "%s/%s" % (dir, file)
if self.transport.has(path):
return # Already there, no need to write again
self.transport.put_bytes(path, obj.as_legacy_object())
def add_pack(self):
"""Add a new pack to this object store.
:return: Fileobject to write to and a commit function to
call when the pack is finished.
"""
fd, path = tempfile.mkstemp(dir=self.pack_dir, suffix=".pack")
f = os.fdopen(fd, 'wb')
def commit():
os.fsync(fd)
f.close()
if os.path.getsize(path) > 0:
self.move_in_pack(path)
return f, commit
class TransportRefsContainer(RefsContainer):
"""Refs container that reads refs from a transport."""
def __init__(self, transport):
self.transport = transport
self._packed_refs = None
self._peeled_refs = {}
def __repr__(self):
return "%s(%r)" % (self.__class__.__name__, self.transport)
def subkeys(self, base):
keys = set()
path = self.refpath(base)
for root, dirs, files in os.walk(path):
dir = root[len(path):].strip("/")
for filename in files:
refname = ("%s/%s" % (dir, filename)).strip("/")
# check_ref_format requires at least one /, so we prepend the
# base before calling it.
if check_ref_format("%s/%s" % (base, refname)):
keys.add(refname)
for key in self.get_packed_refs():
if key.startswith(base):
keys.add(key[len(base):].strip("/"))
return keys
def allkeys(self):
keys = set()
if self.transport.has(self.refpath("HEAD")):
keys.add("HEAD")
path = self.refpath("")
for root, dirs, files in os.walk(self.refpath("refs")):
dir = root[len(path):].strip("/")
for filename in files:
refname = ("%s/%s" % (dir, filename)).strip("/")
if check_ref_format(refname):
keys.add(refname)
keys.update(self.get_packed_refs())
return keys
def get_packed_refs(self):
"""Get contents of the packed-refs file.
:return: Dictionary mapping ref names to SHA1s
:note: Will return an empty dictionary when no packed-refs file is
present.
"""
# TODO: invalidate the cache on repacking
if self._packed_refs is None:
self._packed_refs = {}
path = os.path.join(self.path, 'packed-refs')
try:
f = GitFile(path, 'rb')
except IOError, e:
if e.errno == errno.ENOENT:
return {}
raise
try:
first_line = iter(f).next().rstrip()
if (first_line.startswith("# pack-refs") and " peeled" in
first_line):
for sha, name, peeled in read_packed_refs_with_peeled(f):
self._packed_refs[name] = sha
if peeled:
self._peeled_refs[name] = peeled
else:
f.seek(0)
for sha, name in read_packed_refs(f):
self._packed_refs[name] = sha
finally:
f.close()
return self._packed_refs
def read_loose_ref(self, name):
try:
f = self.transport.get(name)
try:
header = f.read(len(SYMREF))
if header == SYMREF:
# Read only the first line
return header + iter(f).next().rstrip("\n")
else:
# Read only the first 40 bytes
return header + f.read(40-len(SYMREF))
finally:
f.close()
except NoSuchFile:
return None
def _remove_packed_ref(self, name):
if self._packed_refs is None:
return
filename = os.path.join(self.path, 'packed-refs')
# reread cached refs from disk, while holding the lock
f = GitFile(filename, 'wb')
try:
self._packed_refs = None
self.get_packed_refs()
if name not in self._packed_refs:
return
del self._packed_refs[name]
if name in self._peeled_refs:
del self._peeled_refs[name]
write_packed_refs(f, self._packed_refs, self._peeled_refs)
f.close()
finally:
f.abort()
def set_if_equals(self, name, old_ref, new_ref):
"""Set a refname to new_ref only if it currently equals old_ref.
This method follows all symbolic references, and can be used to perform
an atomic compare-and-swap operation.
:param name: The refname to set.
:param old_ref: The old sha the refname must refer to, or None to set
unconditionally.
:param new_ref: The new sha the refname will refer to.
:return: True if the set was successful, False otherwise.
"""
try:
realname, _ = self._follow(name)
except KeyError:
realname = name
dir_transport = self.transport.clone(urlutils.dirname(realname))
dir_transport.create_prefix()
f = GitFile(filename, 'wb')
try:
if old_ref is not None:
try:
# read again while holding the lock
orig_ref = self.read_loose_ref(realname)
if orig_ref is None:
orig_ref = self.get_packed_refs().get(realname, None)
if orig_ref != old_ref:
f.abort()
return False
except (OSError, IOError):
f.abort()
raise
try:
f.write(new_ref+"\n")
except (OSError, IOError):
f.abort()
raise
finally:
f.close()
return True
def add_if_new(self, name, ref):
"""Add a new reference only if it does not already exist."""
self._check_refname(name)
ensure_dir_exists(urlutils.dirname(filename))
f = GitFile(filename, 'wb')
try:
if self.transport.has(name) or name in self.get_packed_refs():
f.abort()
return False
try:
f.write(ref+"\n")
except (OSError, IOError):
f.abort()
raise
finally:
f.close()
return True
def __setitem__(self, name, ref):
"""Set a reference name to point to the given SHA1.
This method follows all symbolic references.
:note: This method unconditionally overwrites the contents of a reference
on disk. To update atomically only if the reference has not changed
on disk, use set_if_equals().
"""
self.set_if_equals(name, None, ref)
def remove_if_equals(self, name, old_ref):
"""Remove a refname only if it currently equals old_ref.
This method does not follow symbolic references. It can be used to
perform an atomic compare-and-delete operation.
:param name: The refname to delete.
:param old_ref: The old sha the refname must refer to, or None to delete
unconditionally.
:return: True if the delete was successful, False otherwise.
"""
self._check_refname(name)
filename = self.refpath(name)
ensure_dir_exists(os.path.dirname(filename))
f = GitFile(filename, 'wb')
try:
if old_ref is not None:
orig_ref = self.read_loose_ref(name)
if orig_ref is None:
orig_ref = self.get_packed_refs().get(name, None)
if orig_ref != old_ref:
return False
# may only be packed
if os.path.exists(filename):
os.remove(filename)
self._remove_packed_ref(name)
finally:
# never write, we just wanted the lock
f.abort()
return True
def __delitem__(self, name):
"""Remove a refname.
This method does not follow symbolic references.
:note: This method unconditionally deletes the contents of a reference
on disk. To delete atomically only if the reference has not changed
on disk, use set_if_equals().
"""
self.remove_if_equals(name, None)
|