~bzr-pqm/bzr/bzr.dev

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
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
# Copyright (C) 2006, 2007, 2008 Canonical Ltd
#
# 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

# TODO: At some point, handle upgrades by just passing the whole request
# across to run on the server.

import bz2

from bzrlib import (
    branch,
    debug,
    errors,
    graph,
    lockdir,
    repository,
    revision,
    symbol_versioning,
    urlutils,
)
from bzrlib.branch import BranchReferenceFormat
from bzrlib.bzrdir import BzrDir, RemoteBzrDirFormat
from bzrlib.decorators import needs_read_lock, needs_write_lock
from bzrlib.errors import (
    NoSuchRevision,
    SmartProtocolError,
    )
from bzrlib.lockable_files import LockableFiles
from bzrlib.smart import client, vfs
from bzrlib.revision import ensure_null, NULL_REVISION
from bzrlib.trace import mutter, note, warning


class _RpcHelper(object):
    """Mixin class that helps with issuing RPCs."""

    def _call(self, method, *args, **err_context):
        try:
            return self._client.call(method, *args)
        except errors.ErrorFromSmartServer, err:
            self._translate_error(err, **err_context)
        
    def _call_expecting_body(self, method, *args, **err_context):
        try:
            return self._client.call_expecting_body(method, *args)
        except errors.ErrorFromSmartServer, err:
            self._translate_error(err, **err_context)
        
    def _call_with_body_bytes_expecting_body(self, method, args, body_bytes,
                                             **err_context):
        try:
            return self._client.call_with_body_bytes_expecting_body(
                method, args, body_bytes)
        except errors.ErrorFromSmartServer, err:
            self._translate_error(err, **err_context)
        
# Note: RemoteBzrDirFormat is in bzrdir.py

class RemoteBzrDir(BzrDir, _RpcHelper):
    """Control directory on a remote server, accessed via bzr:// or similar."""

    def __init__(self, transport, _client=None):
        """Construct a RemoteBzrDir.

        :param _client: Private parameter for testing. Disables probing and the
            use of a real bzrdir.
        """
        BzrDir.__init__(self, transport, RemoteBzrDirFormat())
        # this object holds a delegated bzrdir that uses file-level operations
        # to talk to the other side
        self._real_bzrdir = None

        if _client is None:
            medium = transport.get_smart_medium()
            self._client = client._SmartClient(medium)
        else:
            self._client = _client
            return

        path = self._path_for_remote_call(self._client)
        response = self._call('BzrDir.open', path)
        if response not in [('yes',), ('no',)]:
            raise errors.UnexpectedSmartServerResponse(response)
        if response == ('no',):
            raise errors.NotBranchError(path=transport.base)

    def _ensure_real(self):
        """Ensure that there is a _real_bzrdir set.

        Used before calls to self._real_bzrdir.
        """
        if not self._real_bzrdir:
            self._real_bzrdir = BzrDir.open_from_transport(
                self.root_transport, _server_formats=False)

    def _translate_error(self, err, **context):
        _translate_error(err, bzrdir=self, **context)

    def cloning_metadir(self, stacked=False):
        self._ensure_real()
        return self._real_bzrdir.cloning_metadir(stacked)

    def create_repository(self, shared=False):
        self._ensure_real()
        self._real_bzrdir.create_repository(shared=shared)
        return self.open_repository()

    def destroy_repository(self):
        """See BzrDir.destroy_repository"""
        self._ensure_real()
        self._real_bzrdir.destroy_repository()

    def create_branch(self):
        self._ensure_real()
        real_branch = self._real_bzrdir.create_branch()
        return RemoteBranch(self, self.find_repository(), real_branch)

    def destroy_branch(self):
        """See BzrDir.destroy_branch"""
        self._ensure_real()
        self._real_bzrdir.destroy_branch()

    def create_workingtree(self, revision_id=None, from_branch=None):
        raise errors.NotLocalUrl(self.transport.base)

    def find_branch_format(self):
        """Find the branch 'format' for this bzrdir.

        This might be a synthetic object for e.g. RemoteBranch and SVN.
        """
        b = self.open_branch()
        return b._format

    def get_branch_reference(self):
        """See BzrDir.get_branch_reference()."""
        path = self._path_for_remote_call(self._client)
        response = self._call('BzrDir.open_branch', path)
        if response[0] == 'ok':
            if response[1] == '':
                # branch at this location.
                return None
            else:
                # a branch reference, use the existing BranchReference logic.
                return response[1]
        else:
            raise errors.UnexpectedSmartServerResponse(response)

    def _get_tree_branch(self):
        """See BzrDir._get_tree_branch()."""
        return None, self.open_branch()

    def open_branch(self, _unsupported=False):
        if _unsupported:
            raise NotImplementedError('unsupported flag support not implemented yet.')
        reference_url = self.get_branch_reference()
        if reference_url is None:
            # branch at this location.
            return RemoteBranch(self, self.find_repository())
        else:
            # a branch reference, use the existing BranchReference logic.
            format = BranchReferenceFormat()
            return format.open(self, _found=True, location=reference_url)
                
    def open_repository(self):
        path = self._path_for_remote_call(self._client)
        verb = 'BzrDir.find_repositoryV2'
        try:
            response = self._call(verb, path)
        except errors.UnknownSmartMethod:
            verb = 'BzrDir.find_repository'
            response = self._call(verb, path)
        if response[0] != 'ok':
            raise errors.UnexpectedSmartServerResponse(response)
        if verb == 'BzrDir.find_repository':
            # servers that don't support the V2 method don't support external
            # references either.
            response = response + ('no', )
        if not (len(response) == 5):
            raise SmartProtocolError('incorrect response length %s' % (response,))
        if response[1] == '':
            format = RemoteRepositoryFormat()
            format.rich_root_data = (response[2] == 'yes')
            format.supports_tree_reference = (response[3] == 'yes')
            # No wire format to check this yet.
            format.supports_external_lookups = (response[4] == 'yes')
            # Used to support creating a real format instance when needed.
            format._creating_bzrdir = self
            return RemoteRepository(self, format)
        else:
            raise errors.NoRepositoryPresent(self)

    def open_workingtree(self, recommend_upgrade=True):
        self._ensure_real()
        if self._real_bzrdir.has_workingtree():
            raise errors.NotLocalUrl(self.root_transport)
        else:
            raise errors.NoWorkingTree(self.root_transport.base)

    def _path_for_remote_call(self, client):
        """Return the path to be used for this bzrdir in a remote call."""
        return client.remote_path_from_transport(self.root_transport)

    def get_branch_transport(self, branch_format):
        self._ensure_real()
        return self._real_bzrdir.get_branch_transport(branch_format)

    def get_repository_transport(self, repository_format):
        self._ensure_real()
        return self._real_bzrdir.get_repository_transport(repository_format)

    def get_workingtree_transport(self, workingtree_format):
        self._ensure_real()
        return self._real_bzrdir.get_workingtree_transport(workingtree_format)

    def can_convert_format(self):
        """Upgrading of remote bzrdirs is not supported yet."""
        return False

    def needs_format_conversion(self, format=None):
        """Upgrading of remote bzrdirs is not supported yet."""
        return False

    def clone(self, url, revision_id=None, force_new_repo=False,
              preserve_stacking=False):
        self._ensure_real()
        return self._real_bzrdir.clone(url, revision_id=revision_id,
            force_new_repo=force_new_repo, preserve_stacking=preserve_stacking)

    def get_config(self):
        self._ensure_real()
        return self._real_bzrdir.get_config()


class RemoteRepositoryFormat(repository.RepositoryFormat):
    """Format for repositories accessed over a _SmartClient.

    Instances of this repository are represented by RemoteRepository
    instances.

    The RemoteRepositoryFormat is parameterized during construction
    to reflect the capabilities of the real, remote format. Specifically
    the attributes rich_root_data and supports_tree_reference are set
    on a per instance basis, and are not set (and should not be) at
    the class level.
    """

    _matchingbzrdir = RemoteBzrDirFormat()

    def initialize(self, a_bzrdir, shared=False):
        if not isinstance(a_bzrdir, RemoteBzrDir):
            prior_repo = self._creating_bzrdir.open_repository()
            prior_repo._ensure_real()
            return prior_repo._real_repository._format.initialize(
                a_bzrdir, shared=shared)
        return a_bzrdir.create_repository(shared=shared)
    
    def open(self, a_bzrdir):
        if not isinstance(a_bzrdir, RemoteBzrDir):
            raise AssertionError('%r is not a RemoteBzrDir' % (a_bzrdir,))
        return a_bzrdir.open_repository()

    def get_format_description(self):
        return 'bzr remote repository'

    def __eq__(self, other):
        return self.__class__ == other.__class__

    def check_conversion_target(self, target_format):
        if self.rich_root_data and not target_format.rich_root_data:
            raise errors.BadConversionTarget(
                'Does not support rich root data.', target_format)
        if (self.supports_tree_reference and
            not getattr(target_format, 'supports_tree_reference', False)):
            raise errors.BadConversionTarget(
                'Does not support nested trees', target_format)


class RemoteRepository(_RpcHelper):
    """Repository accessed over rpc.

    For the moment most operations are performed using local transport-backed
    Repository objects.
    """

    def __init__(self, remote_bzrdir, format, real_repository=None, _client=None):
        """Create a RemoteRepository instance.
        
        :param remote_bzrdir: The bzrdir hosting this repository.
        :param format: The RemoteFormat object to use.
        :param real_repository: If not None, a local implementation of the
            repository logic for the repository, usually accessing the data
            via the VFS.
        :param _client: Private testing parameter - override the smart client
            to be used by the repository.
        """
        if real_repository:
            self._real_repository = real_repository
        else:
            self._real_repository = None
        self.bzrdir = remote_bzrdir
        if _client is None:
            self._client = remote_bzrdir._client
        else:
            self._client = _client
        self._format = format
        self._lock_mode = None
        self._lock_token = None
        self._lock_count = 0
        self._leave_lock = False
        # A cache of looked up revision parent data; reset at unlock time.
        self._parents_map = None
        if 'hpss' in debug.debug_flags:
            self._requested_parents = None
        # For tests:
        # These depend on the actual remote format, so force them off for
        # maximum compatibility. XXX: In future these should depend on the
        # remote repository instance, but this is irrelevant until we perform
        # reconcile via an RPC call.
        self._reconcile_does_inventory_gc = False
        self._reconcile_fixes_text_parents = False
        self._reconcile_backsup_inventory = False
        self.base = self.bzrdir.transport.base
        # Additional places to query for data.
        self._fallback_repositories = []

    def __str__(self):
        return "%s(%s)" % (self.__class__.__name__, self.base)

    __repr__ = __str__

    def abort_write_group(self):
        """Complete a write group on the decorated repository.
        
        Smart methods peform operations in a single step so this api
        is not really applicable except as a compatibility thunk
        for older plugins that don't use e.g. the CommitBuilder
        facility.
        """
        self._ensure_real()
        return self._real_repository.abort_write_group()

    def commit_write_group(self):
        """Complete a write group on the decorated repository.
        
        Smart methods peform operations in a single step so this api
        is not really applicable except as a compatibility thunk
        for older plugins that don't use e.g. the CommitBuilder
        facility.
        """
        self._ensure_real()
        return self._real_repository.commit_write_group()

    def _ensure_real(self):
        """Ensure that there is a _real_repository set.

        Used before calls to self._real_repository.
        """
        if self._real_repository is None:
            self.bzrdir._ensure_real()
            self._set_real_repository(
                self.bzrdir._real_bzrdir.open_repository())

    def _translate_error(self, err, **context):
        self.bzrdir._translate_error(err, repository=self, **context)

    def find_text_key_references(self):
        """Find the text key references within the repository.

        :return: a dictionary mapping (file_id, revision_id) tuples to altered file-ids to an iterable of
        revision_ids. Each altered file-ids has the exact revision_ids that
        altered it listed explicitly.
        :return: A dictionary mapping text keys ((fileid, revision_id) tuples)
            to whether they were referred to by the inventory of the
            revision_id that they contain. The inventory texts from all present
            revision ids are assessed to generate this report.
        """
        self._ensure_real()
        return self._real_repository.find_text_key_references()

    def _generate_text_key_index(self):
        """Generate a new text key index for the repository.

        This is an expensive function that will take considerable time to run.

        :return: A dict mapping (file_id, revision_id) tuples to a list of
            parents, also (file_id, revision_id) tuples.
        """
        self._ensure_real()
        return self._real_repository._generate_text_key_index()

    @symbol_versioning.deprecated_method(symbol_versioning.one_four)
    def get_revision_graph(self, revision_id=None):
        """See Repository.get_revision_graph()."""
        return self._get_revision_graph(revision_id)

    def _get_revision_graph(self, revision_id):
        """Private method for using with old (< 1.2) servers to fallback."""
        if revision_id is None:
            revision_id = ''
        elif revision.is_null(revision_id):
            return {}

        path = self.bzrdir._path_for_remote_call(self._client)
        response = self._call_expecting_body(
            'Repository.get_revision_graph', path, revision_id)
        response_tuple, response_handler = response
        if response_tuple[0] != 'ok':
            raise errors.UnexpectedSmartServerResponse(response_tuple)
        coded = response_handler.read_body_bytes()
        if coded == '':
            # no revisions in this repository!
            return {}
        lines = coded.split('\n')
        revision_graph = {}
        for line in lines:
            d = tuple(line.split())
            revision_graph[d[0]] = d[1:]
            
        return revision_graph

    def has_revision(self, revision_id):
        """See Repository.has_revision()."""
        if revision_id == NULL_REVISION:
            # The null revision is always present.
            return True
        path = self.bzrdir._path_for_remote_call(self._client)
        response = self._call('Repository.has_revision', path, revision_id)
        if response[0] not in ('yes', 'no'):
            raise errors.UnexpectedSmartServerResponse(response)
        if response[0] == 'yes':
            return True
        for fallback_repo in self._fallback_repositories:
            if fallback_repo.has_revision(revision_id):
                return True
        return False

    def has_revisions(self, revision_ids):
        """See Repository.has_revisions()."""
        # FIXME: This does many roundtrips, particularly when there are
        # fallback repositories.  -- mbp 20080905
        result = set()
        for revision_id in revision_ids:
            if self.has_revision(revision_id):
                result.add(revision_id)
        return result

    def has_same_location(self, other):
        return (self.__class__ == other.__class__ and
                self.bzrdir.transport.base == other.bzrdir.transport.base)
        
    def get_graph(self, other_repository=None):
        """Return the graph for this repository format"""
        parents_provider = self
        if (other_repository is not None and
            other_repository.bzrdir.transport.base !=
            self.bzrdir.transport.base):
            parents_provider = graph._StackedParentsProvider(
                [parents_provider, other_repository._make_parents_provider()])
        return graph.Graph(parents_provider)

    def gather_stats(self, revid=None, committers=None):
        """See Repository.gather_stats()."""
        path = self.bzrdir._path_for_remote_call(self._client)
        # revid can be None to indicate no revisions, not just NULL_REVISION
        if revid is None or revision.is_null(revid):
            fmt_revid = ''
        else:
            fmt_revid = revid
        if committers is None or not committers:
            fmt_committers = 'no'
        else:
            fmt_committers = 'yes'
        response_tuple, response_handler = self._call_expecting_body(
            'Repository.gather_stats', path, fmt_revid, fmt_committers)
        if response_tuple[0] != 'ok':
            raise errors.UnexpectedSmartServerResponse(response_tuple)

        body = response_handler.read_body_bytes()
        result = {}
        for line in body.split('\n'):
            if not line:
                continue
            key, val_text = line.split(':')
            if key in ('revisions', 'size', 'committers'):
                result[key] = int(val_text)
            elif key in ('firstrev', 'latestrev'):
                values = val_text.split(' ')[1:]
                result[key] = (float(values[0]), long(values[1]))

        return result

    def find_branches(self, using=False):
        """See Repository.find_branches()."""
        # should be an API call to the server.
        self._ensure_real()
        return self._real_repository.find_branches(using=using)

    def get_physical_lock_status(self):
        """See Repository.get_physical_lock_status()."""
        # should be an API call to the server.
        self._ensure_real()
        return self._real_repository.get_physical_lock_status()

    def is_in_write_group(self):
        """Return True if there is an open write group.

        write groups are only applicable locally for the smart server..
        """
        if self._real_repository:
            return self._real_repository.is_in_write_group()

    def is_locked(self):
        return self._lock_count >= 1

    def is_shared(self):
        """See Repository.is_shared()."""
        path = self.bzrdir._path_for_remote_call(self._client)
        response = self._call('Repository.is_shared', path)
        if response[0] not in ('yes', 'no'):
            raise SmartProtocolError('unexpected response code %s' % (response,))
        return response[0] == 'yes'

    def is_write_locked(self):
        return self._lock_mode == 'w'

    def lock_read(self):
        # wrong eventually - want a local lock cache context
        if not self._lock_mode:
            self._lock_mode = 'r'
            self._lock_count = 1
            self._parents_map = {}
            if 'hpss' in debug.debug_flags:
                self._requested_parents = set()
            if self._real_repository is not None:
                self._real_repository.lock_read()
        else:
            self._lock_count += 1

    def _remote_lock_write(self, token):
        path = self.bzrdir._path_for_remote_call(self._client)
        if token is None:
            token = ''
        err_context = {'token': token}
        response = self._call('Repository.lock_write', path, token,
                              **err_context)
        if response[0] == 'ok':
            ok, token = response
            return token
        else:
            raise errors.UnexpectedSmartServerResponse(response)

    def lock_write(self, token=None, _skip_rpc=False):
        if not self._lock_mode:
            if _skip_rpc:
                if self._lock_token is not None:
                    if token != self._lock_token:
                        raise errors.TokenMismatch(token, self._lock_token)
                self._lock_token = token
            else:
                self._lock_token = self._remote_lock_write(token)
            # if self._lock_token is None, then this is something like packs or
            # svn where we don't get to lock the repo, or a weave style repository
            # where we cannot lock it over the wire and attempts to do so will
            # fail.
            if self._real_repository is not None:
                self._real_repository.lock_write(token=self._lock_token)
            if token is not None:
                self._leave_lock = True
            else:
                self._leave_lock = False
            self._lock_mode = 'w'
            self._lock_count = 1
            self._parents_map = {}
            if 'hpss' in debug.debug_flags:
                self._requested_parents = set()
        elif self._lock_mode == 'r':
            raise errors.ReadOnlyError(self)
        else:
            self._lock_count += 1
        return self._lock_token or None

    def leave_lock_in_place(self):
        if not self._lock_token:
            raise NotImplementedError(self.leave_lock_in_place)
        self._leave_lock = True

    def dont_leave_lock_in_place(self):
        if not self._lock_token:
            raise NotImplementedError(self.dont_leave_lock_in_place)
        self._leave_lock = False

    def _set_real_repository(self, repository):
        """Set the _real_repository for this repository.

        :param repository: The repository to fallback to for non-hpss
            implemented operations.
        """
        if self._real_repository is not None:
            raise AssertionError('_real_repository is already set')
        if isinstance(repository, RemoteRepository):
            raise AssertionError()
        self._real_repository = repository
        for fb in self._fallback_repositories:
            self._real_repository.add_fallback_repository(fb)
        if self._lock_mode == 'w':
            # if we are already locked, the real repository must be able to
            # acquire the lock with our token.
            self._real_repository.lock_write(self._lock_token)
        elif self._lock_mode == 'r':
            self._real_repository.lock_read()

    def start_write_group(self):
        """Start a write group on the decorated repository.
        
        Smart methods peform operations in a single step so this api
        is not really applicable except as a compatibility thunk
        for older plugins that don't use e.g. the CommitBuilder
        facility.
        """
        self._ensure_real()
        return self._real_repository.start_write_group()

    def _unlock(self, token):
        path = self.bzrdir._path_for_remote_call(self._client)
        if not token:
            # with no token the remote repository is not persistently locked.
            return
        err_context = {'token': token}
        response = self._call('Repository.unlock', path, token,
                              **err_context)
        if response == ('ok',):
            return
        else:
            raise errors.UnexpectedSmartServerResponse(response)

    def unlock(self):
        self._lock_count -= 1
        if self._lock_count > 0:
            return
        self._parents_map = None
        if 'hpss' in debug.debug_flags:
            self._requested_parents = None
        old_mode = self._lock_mode
        self._lock_mode = None
        try:
            # The real repository is responsible at present for raising an
            # exception if it's in an unfinished write group.  However, it
            # normally will *not* actually remove the lock from disk - that's
            # done by the server on receiving the Repository.unlock call.
            # This is just to let the _real_repository stay up to date.
            if self._real_repository is not None:
                self._real_repository.unlock()
        finally:
            # The rpc-level lock should be released even if there was a
            # problem releasing the vfs-based lock.
            if old_mode == 'w':
                # Only write-locked repositories need to make a remote method
                # call to perfom the unlock.
                old_token = self._lock_token
                self._lock_token = None
                if not self._leave_lock:
                    self._unlock(old_token)

    def break_lock(self):
        # should hand off to the network
        self._ensure_real()
        return self._real_repository.break_lock()

    def _get_tarball(self, compression):
        """Return a TemporaryFile containing a repository tarball.
        
        Returns None if the server does not support sending tarballs.
        """
        import tempfile
        path = self.bzrdir._path_for_remote_call(self._client)
        try:
            response, protocol = self._call_expecting_body(
                'Repository.tarball', path, compression)
        except errors.UnknownSmartMethod:
            protocol.cancel_read_body()
            return None
        if response[0] == 'ok':
            # Extract the tarball and return it
            t = tempfile.NamedTemporaryFile()
            # TODO: rpc layer should read directly into it...
            t.write(protocol.read_body_bytes())
            t.seek(0)
            return t
        raise errors.UnexpectedSmartServerResponse(response)

    def sprout(self, to_bzrdir, revision_id=None):
        # TODO: Option to control what format is created?
        self._ensure_real()
        dest_repo = self._real_repository._format.initialize(to_bzrdir,
                                                             shared=False)
        dest_repo.fetch(self, revision_id=revision_id)
        return dest_repo

    ### These methods are just thin shims to the VFS object for now.

    def revision_tree(self, revision_id):
        self._ensure_real()
        return self._real_repository.revision_tree(revision_id)

    def get_serializer_format(self):
        self._ensure_real()
        return self._real_repository.get_serializer_format()

    def get_commit_builder(self, branch, parents, config, timestamp=None,
                           timezone=None, committer=None, revprops=None,
                           revision_id=None):
        # FIXME: It ought to be possible to call this without immediately
        # triggering _ensure_real.  For now it's the easiest thing to do.
        self._ensure_real()
        real_repo = self._real_repository
        builder = real_repo.get_commit_builder(branch, parents,
                config, timestamp=timestamp, timezone=timezone,
                committer=committer, revprops=revprops, revision_id=revision_id)
        return builder

    def add_fallback_repository(self, repository):
        """Add a repository to use for looking up data not held locally.
        
        :param repository: A repository.
        """
        # XXX: At the moment the RemoteRepository will allow fallbacks
        # unconditionally - however, a _real_repository will usually exist,
        # and may raise an error if it's not accommodated by the underlying
        # format.  Eventually we should check when opening the repository
        # whether it's willing to allow them or not.
        #
        # We need to accumulate additional repositories here, to pass them in
        # on various RPC's.
        self._fallback_repositories.append(repository)
        # They are also seen by the fallback repository.  If it doesn't exist
        # yet they'll be added then.  This implicitly copies them.
        self._ensure_real()

    def add_inventory(self, revid, inv, parents):
        self._ensure_real()
        return self._real_repository.add_inventory(revid, inv, parents)

    def add_revision(self, rev_id, rev, inv=None, config=None):
        self._ensure_real()
        return self._real_repository.add_revision(
            rev_id, rev, inv=inv, config=config)

    @needs_read_lock
    def get_inventory(self, revision_id):
        self._ensure_real()
        return self._real_repository.get_inventory(revision_id)

    def iter_inventories(self, revision_ids):
        self._ensure_real()
        return self._real_repository.iter_inventories(revision_ids)

    @needs_read_lock
    def get_revision(self, revision_id):
        self._ensure_real()
        return self._real_repository.get_revision(revision_id)

    def get_transaction(self):
        self._ensure_real()
        return self._real_repository.get_transaction()

    @needs_read_lock
    def clone(self, a_bzrdir, revision_id=None):
        self._ensure_real()
        return self._real_repository.clone(a_bzrdir, revision_id=revision_id)

    def make_working_trees(self):
        """See Repository.make_working_trees"""
        self._ensure_real()
        return self._real_repository.make_working_trees()

    def revision_ids_to_search_result(self, result_set):
        """Convert a set of revision ids to a graph SearchResult."""
        result_parents = set()
        for parents in self.get_graph().get_parent_map(
            result_set).itervalues():
            result_parents.update(parents)
        included_keys = result_set.intersection(result_parents)
        start_keys = result_set.difference(included_keys)
        exclude_keys = result_parents.difference(result_set)
        result = graph.SearchResult(start_keys, exclude_keys,
            len(result_set), result_set)
        return result

    @needs_read_lock
    def search_missing_revision_ids(self, other, revision_id=None, find_ghosts=True):
        """Return the revision ids that other has that this does not.
        
        These are returned in topological order.

        revision_id: only return revision ids included by revision_id.
        """
        return repository.InterRepository.get(
            other, self).search_missing_revision_ids(revision_id, find_ghosts)

    def fetch(self, source, revision_id=None, pb=None, find_ghosts=False):
        if self.has_same_location(source):
            # check that last_revision is in 'from' and then return a
            # no-operation.
            if (revision_id is not None and
                not revision.is_null(revision_id)):
                self.get_revision(revision_id)
            return 0, []
        inter = repository.InterRepository.get(source, self)
        try:
            return inter.fetch(revision_id=revision_id, pb=pb, find_ghosts=find_ghosts)

        except NotImplementedError:
            raise errors.IncompatibleRepositories(source, self)

    def create_bundle(self, target, base, fileobj, format=None):
        self._ensure_real()
        self._real_repository.create_bundle(target, base, fileobj, format)

    @needs_read_lock
    def get_ancestry(self, revision_id, topo_sorted=True):
        self._ensure_real()
        return self._real_repository.get_ancestry(revision_id, topo_sorted)

    def fileids_altered_by_revision_ids(self, revision_ids):
        self._ensure_real()
        return self._real_repository.fileids_altered_by_revision_ids(revision_ids)

    def _get_versioned_file_checker(self, revisions, revision_versions_cache):
        self._ensure_real()
        return self._real_repository._get_versioned_file_checker(
            revisions, revision_versions_cache)
        
    def iter_files_bytes(self, desired_files):
        """See Repository.iter_file_bytes.
        """
        self._ensure_real()
        return self._real_repository.iter_files_bytes(desired_files)

    @property
    def _fetch_order(self):
        """Decorate the real repository for now.

        In the long term getting this back from the remote repository as part
        of open would be more efficient.
        """
        self._ensure_real()
        return self._real_repository._fetch_order

    @property
    def _fetch_uses_deltas(self):
        """Decorate the real repository for now.

        In the long term getting this back from the remote repository as part
        of open would be more efficient.
        """
        self._ensure_real()
        return self._real_repository._fetch_uses_deltas

    @property
    def _fetch_reconcile(self):
        """Decorate the real repository for now.

        In the long term getting this back from the remote repository as part
        of open would be more efficient.
        """
        self._ensure_real()
        return self._real_repository._fetch_reconcile

    def get_parent_map(self, keys):
        """See bzrlib.Graph.get_parent_map()."""
        # Hack to build up the caching logic.
        ancestry = self._parents_map
        if ancestry is None:
            # Repository is not locked, so there's no cache.
            missing_revisions = set(keys)
            ancestry = {}
        else:
            missing_revisions = set(key for key in keys if key not in ancestry)
        if missing_revisions:
            parent_map = self._get_parent_map(missing_revisions)
            if 'hpss' in debug.debug_flags:
                mutter('retransmitted revisions: %d of %d',
                        len(set(ancestry).intersection(parent_map)),
                        len(parent_map))
            ancestry.update(parent_map)
        present_keys = [k for k in keys if k in ancestry]
        if 'hpss' in debug.debug_flags:
            if self._requested_parents is not None and len(ancestry) != 0:
                self._requested_parents.update(present_keys)
                mutter('Current RemoteRepository graph hit rate: %d%%',
                    100.0 * len(self._requested_parents) / len(ancestry))
        return dict((k, ancestry[k]) for k in present_keys)

    def _get_parent_map(self, keys):
        """Helper for get_parent_map that performs the RPC."""
        medium = self._client._medium
        if medium._is_remote_before((1, 2)):
            # We already found out that the server can't understand
            # Repository.get_parent_map requests, so just fetch the whole
            # graph.
            # XXX: Note that this will issue a deprecation warning. This is ok
            # :- its because we're working with a deprecated server anyway, and
            # the user will almost certainly have seen a warning about the
            # server version already.
            rg = self.get_revision_graph()
            # There is an api discrepency between get_parent_map and
            # get_revision_graph. Specifically, a "key:()" pair in
            # get_revision_graph just means a node has no parents. For
            # "get_parent_map" it means the node is a ghost. So fix up the
            # graph to correct this.
            #   https://bugs.launchpad.net/bzr/+bug/214894
            # There is one other "bug" which is that ghosts in
            # get_revision_graph() are not returned at all. But we won't worry
            # about that for now.
            for node_id, parent_ids in rg.iteritems():
                if parent_ids == ():
                    rg[node_id] = (NULL_REVISION,)
            rg[NULL_REVISION] = ()
            return rg

        keys = set(keys)
        if None in keys:
            raise ValueError('get_parent_map(None) is not valid')
        if NULL_REVISION in keys:
            keys.discard(NULL_REVISION)
            found_parents = {NULL_REVISION:()}
            if not keys:
                return found_parents
        else:
            found_parents = {}
        # TODO(Needs analysis): We could assume that the keys being requested
        # from get_parent_map are in a breadth first search, so typically they
        # will all be depth N from some common parent, and we don't have to
        # have the server iterate from the root parent, but rather from the
        # keys we're searching; and just tell the server the keyspace we
        # already have; but this may be more traffic again.

        # Transform self._parents_map into a search request recipe.
        # TODO: Manage this incrementally to avoid covering the same path
        # repeatedly. (The server will have to on each request, but the less
        # work done the better).
        parents_map = self._parents_map
        if parents_map is None:
            # Repository is not locked, so there's no cache.
            parents_map = {}
        start_set = set(parents_map)
        result_parents = set()
        for parents in parents_map.itervalues():
            result_parents.update(parents)
        stop_keys = result_parents.difference(start_set)
        included_keys = start_set.intersection(result_parents)
        start_set.difference_update(included_keys)
        recipe = (start_set, stop_keys, len(parents_map))
        body = self._serialise_search_recipe(recipe)
        path = self.bzrdir._path_for_remote_call(self._client)
        for key in keys:
            if type(key) is not str:
                raise ValueError(
                    "key %r not a plain string" % (key,))
        verb = 'Repository.get_parent_map'
        args = (path,) + tuple(keys)
        try:
            response = self._call_with_body_bytes_expecting_body(
                verb, args, body)
        except errors.UnknownSmartMethod:
            # Server does not support this method, so get the whole graph.
            # Worse, we have to force a disconnection, because the server now
            # doesn't realise it has a body on the wire to consume, so the
            # only way to recover is to abandon the connection.
            warning(
                'Server is too old for fast get_parent_map, reconnecting.  '
                '(Upgrade the server to Bazaar 1.2 to avoid this)')
            medium.disconnect()
            # To avoid having to disconnect repeatedly, we keep track of the
            # fact the server doesn't understand remote methods added in 1.2.
            medium._remember_remote_is_before((1, 2))
            return self.get_revision_graph(None)
        response_tuple, response_handler = response
        if response_tuple[0] not in ['ok']:
            response_handler.cancel_read_body()
            raise errors.UnexpectedSmartServerResponse(response_tuple)
        if response_tuple[0] == 'ok':
            coded = bz2.decompress(response_handler.read_body_bytes())
            if coded == '':
                # no revisions found
                return {}
            lines = coded.split('\n')
            revision_graph = {}
            for line in lines:
                d = tuple(line.split())
                if len(d) > 1:
                    revision_graph[d[0]] = d[1:]
                else:
                    # No parents - so give the Graph result (NULL_REVISION,).
                    revision_graph[d[0]] = (NULL_REVISION,)
            return revision_graph

    @needs_read_lock
    def get_signature_text(self, revision_id):
        self._ensure_real()
        return self._real_repository.get_signature_text(revision_id)

    @needs_read_lock
    @symbol_versioning.deprecated_method(symbol_versioning.one_three)
    def get_revision_graph_with_ghosts(self, revision_ids=None):
        self._ensure_real()
        return self._real_repository.get_revision_graph_with_ghosts(
            revision_ids=revision_ids)

    @needs_read_lock
    def get_inventory_xml(self, revision_id):
        self._ensure_real()
        return self._real_repository.get_inventory_xml(revision_id)

    def deserialise_inventory(self, revision_id, xml):
        self._ensure_real()
        return self._real_repository.deserialise_inventory(revision_id, xml)

    def reconcile(self, other=None, thorough=False):
        self._ensure_real()
        return self._real_repository.reconcile(other=other, thorough=thorough)
        
    def all_revision_ids(self):
        self._ensure_real()
        return self._real_repository.all_revision_ids()
    
    @needs_read_lock
    def get_deltas_for_revisions(self, revisions):
        self._ensure_real()
        return self._real_repository.get_deltas_for_revisions(revisions)

    @needs_read_lock
    def get_revision_delta(self, revision_id):
        self._ensure_real()
        return self._real_repository.get_revision_delta(revision_id)

    @needs_read_lock
    def revision_trees(self, revision_ids):
        self._ensure_real()
        return self._real_repository.revision_trees(revision_ids)

    @needs_read_lock
    def get_revision_reconcile(self, revision_id):
        self._ensure_real()
        return self._real_repository.get_revision_reconcile(revision_id)

    @needs_read_lock
    def check(self, revision_ids=None):
        self._ensure_real()
        return self._real_repository.check(revision_ids=revision_ids)

    def copy_content_into(self, destination, revision_id=None):
        self._ensure_real()
        return self._real_repository.copy_content_into(
            destination, revision_id=revision_id)

    def _copy_repository_tarball(self, to_bzrdir, revision_id=None):
        # get a tarball of the remote repository, and copy from that into the
        # destination
        from bzrlib import osutils
        import tarfile
        # TODO: Maybe a progress bar while streaming the tarball?
        note("Copying repository content as tarball...")
        tar_file = self._get_tarball('bz2')
        if tar_file is None:
            return None
        destination = to_bzrdir.create_repository()
        try:
            tar = tarfile.open('repository', fileobj=tar_file,
                mode='r|bz2')
            tmpdir = osutils.mkdtemp()
            try:
                _extract_tar(tar, tmpdir)
                tmp_bzrdir = BzrDir.open(tmpdir)
                tmp_repo = tmp_bzrdir.open_repository()
                tmp_repo.copy_content_into(destination, revision_id)
            finally:
                osutils.rmtree(tmpdir)
        finally:
            tar_file.close()
        return destination
        # TODO: Suggestion from john: using external tar is much faster than
        # python's tarfile library, but it may not work on windows.

    @property
    def inventories(self):
        """Decorate the real repository for now.

        In the long term a full blown network facility is needed to
        avoid creating a real repository object locally.
        """
        self._ensure_real()
        return self._real_repository.inventories

    @needs_write_lock
    def pack(self):
        """Compress the data within the repository.

        This is not currently implemented within the smart server.
        """
        self._ensure_real()
        return self._real_repository.pack()

    @property
    def revisions(self):
        """Decorate the real repository for now.

        In the short term this should become a real object to intercept graph
        lookups.

        In the long term a full blown network facility is needed.
        """
        self._ensure_real()
        return self._real_repository.revisions

    def set_make_working_trees(self, new_value):
        self._ensure_real()
        self._real_repository.set_make_working_trees(new_value)

    @property
    def signatures(self):
        """Decorate the real repository for now.

        In the long term a full blown network facility is needed to avoid
        creating a real repository object locally.
        """
        self._ensure_real()
        return self._real_repository.signatures

    @needs_write_lock
    def sign_revision(self, revision_id, gpg_strategy):
        self._ensure_real()
        return self._real_repository.sign_revision(revision_id, gpg_strategy)

    @property
    def texts(self):
        """Decorate the real repository for now.

        In the long term a full blown network facility is needed to avoid
        creating a real repository object locally.
        """
        self._ensure_real()
        return self._real_repository.texts

    @needs_read_lock
    def get_revisions(self, revision_ids):
        self._ensure_real()
        return self._real_repository.get_revisions(revision_ids)

    def supports_rich_root(self):
        self._ensure_real()
        return self._real_repository.supports_rich_root()

    def iter_reverse_revision_history(self, revision_id):
        self._ensure_real()
        return self._real_repository.iter_reverse_revision_history(revision_id)

    @property
    def _serializer(self):
        self._ensure_real()
        return self._real_repository._serializer

    def store_revision_signature(self, gpg_strategy, plaintext, revision_id):
        self._ensure_real()
        return self._real_repository.store_revision_signature(
            gpg_strategy, plaintext, revision_id)

    def add_signature_text(self, revision_id, signature):
        self._ensure_real()
        return self._real_repository.add_signature_text(revision_id, signature)

    def has_signature_for_revision_id(self, revision_id):
        self._ensure_real()
        return self._real_repository.has_signature_for_revision_id(revision_id)

    def item_keys_introduced_by(self, revision_ids, _files_pb=None):
        self._ensure_real()
        return self._real_repository.item_keys_introduced_by(revision_ids,
            _files_pb=_files_pb)

    def revision_graph_can_have_wrong_parents(self):
        # The answer depends on the remote repo format.
        self._ensure_real()
        return self._real_repository.revision_graph_can_have_wrong_parents()

    def _find_inconsistent_revision_parents(self):
        self._ensure_real()
        return self._real_repository._find_inconsistent_revision_parents()

    def _check_for_inconsistent_revision_parents(self):
        self._ensure_real()
        return self._real_repository._check_for_inconsistent_revision_parents()

    def _make_parents_provider(self):
        return self

    def _serialise_search_recipe(self, recipe):
        """Serialise a graph search recipe.

        :param recipe: A search recipe (start, stop, count).
        :return: Serialised bytes.
        """
        start_keys = ' '.join(recipe[0])
        stop_keys = ' '.join(recipe[1])
        count = str(recipe[2])
        return '\n'.join((start_keys, stop_keys, count))


class RemoteBranchLockableFiles(LockableFiles):
    """A 'LockableFiles' implementation that talks to a smart server.
    
    This is not a public interface class.
    """

    def __init__(self, bzrdir, _client):
        self.bzrdir = bzrdir
        self._client = _client
        self._need_find_modes = True
        LockableFiles.__init__(
            self, bzrdir.get_branch_transport(None),
            'lock', lockdir.LockDir)

    def _find_modes(self):
        # RemoteBranches don't let the client set the mode of control files.
        self._dir_mode = None
        self._file_mode = None


class RemoteBranchFormat(branch.BranchFormat):

    def __eq__(self, other):
        return (isinstance(other, RemoteBranchFormat) and 
            self.__dict__ == other.__dict__)

    def get_format_description(self):
        return 'Remote BZR Branch'

    def get_format_string(self):
        return 'Remote BZR Branch'

    def open(self, a_bzrdir):
        return a_bzrdir.open_branch()

    def initialize(self, a_bzrdir):
        return a_bzrdir.create_branch()

    def supports_tags(self):
        # Remote branches might support tags, but we won't know until we
        # access the real remote branch.
        return True


class RemoteBranch(branch.Branch, _RpcHelper):
    """Branch stored on a server accessed by HPSS RPC.

    At the moment most operations are mapped down to simple file operations.
    """

    def __init__(self, remote_bzrdir, remote_repository, real_branch=None,
        _client=None):
        """Create a RemoteBranch instance.

        :param real_branch: An optional local implementation of the branch
            format, usually accessing the data via the VFS.
        :param _client: Private parameter for testing.
        """
        # We intentionally don't call the parent class's __init__, because it
        # will try to assign to self.tags, which is a property in this subclass.
        # And the parent's __init__ doesn't do much anyway.
        self._revision_id_to_revno_cache = None
        self._revision_history_cache = None
        self._last_revision_info_cache = None
        self.bzrdir = remote_bzrdir
        if _client is not None:
            self._client = _client
        else:
            self._client = remote_bzrdir._client
        self.repository = remote_repository
        if real_branch is not None:
            self._real_branch = real_branch
            # Give the remote repository the matching real repo.
            real_repo = self._real_branch.repository
            if isinstance(real_repo, RemoteRepository):
                real_repo._ensure_real()
                real_repo = real_repo._real_repository
            self.repository._set_real_repository(real_repo)
            # Give the branch the remote repository to let fast-pathing happen.
            self._real_branch.repository = self.repository
        else:
            self._real_branch = None
        # Fill out expected attributes of branch for bzrlib api users.
        self._format = RemoteBranchFormat()
        self.base = self.bzrdir.root_transport.base
        self._control_files = None
        self._lock_mode = None
        self._lock_token = None
        self._repo_lock_token = None
        self._lock_count = 0
        self._leave_lock = False
        # The base class init is not called, so we duplicate this:
        hooks = branch.Branch.hooks['open']
        for hook in hooks:
            hook(self)
        self._setup_stacking()

    def _setup_stacking(self):
        # configure stacking into the remote repository, by reading it from
        # the vfs branch.
        try:
            fallback_url = self.get_stacked_on_url()
        except (errors.NotStacked, errors.UnstackableBranchFormat,
            errors.UnstackableRepositoryFormat), e:
            return
        # it's relative to this branch...
        fallback_url = urlutils.join(self.base, fallback_url)
        transports = [self.bzrdir.root_transport]
        if self._real_branch is not None:
            transports.append(self._real_branch._transport)
        fallback_bzrdir = BzrDir.open(fallback_url, transports)
        fallback_repo = fallback_bzrdir.open_repository()
        self.repository.add_fallback_repository(fallback_repo)

    def _get_real_transport(self):
        # if we try vfs access, return the real branch's vfs transport
        self._ensure_real()
        return self._real_branch._transport

    _transport = property(_get_real_transport)

    def __str__(self):
        return "%s(%s)" % (self.__class__.__name__, self.base)

    __repr__ = __str__

    def _ensure_real(self):
        """Ensure that there is a _real_branch set.

        Used before calls to self._real_branch.
        """
        if self._real_branch is None:
            if not vfs.vfs_enabled():
                raise AssertionError('smart server vfs must be enabled '
                    'to use vfs implementation')
            self.bzrdir._ensure_real()
            self._real_branch = self.bzrdir._real_bzrdir.open_branch()
            if self.repository._real_repository is None:
                # Give the remote repository the matching real repo.
                real_repo = self._real_branch.repository
                if isinstance(real_repo, RemoteRepository):
                    real_repo._ensure_real()
                    real_repo = real_repo._real_repository
                self.repository._set_real_repository(real_repo)
            # Give the real branch the remote repository to let fast-pathing
            # happen.
            self._real_branch.repository = self.repository
            if self._lock_mode == 'r':
                self._real_branch.lock_read()
            elif self._lock_mode == 'w':
                self._real_branch.lock_write(token=self._lock_token)

    def _translate_error(self, err, **context):
        self.repository._translate_error(err, branch=self, **context)

    def _clear_cached_state(self):
        super(RemoteBranch, self)._clear_cached_state()
        if self._real_branch is not None:
            self._real_branch._clear_cached_state()

    def _clear_cached_state_of_remote_branch_only(self):
        """Like _clear_cached_state, but doesn't clear the cache of
        self._real_branch.

        This is useful when falling back to calling a method of
        self._real_branch that changes state.  In that case the underlying
        branch changes, so we need to invalidate this RemoteBranch's cache of
        it.  However, there's no need to invalidate the _real_branch's cache
        too, in fact doing so might harm performance.
        """
        super(RemoteBranch, self)._clear_cached_state()
        
    @property
    def control_files(self):
        # Defer actually creating RemoteBranchLockableFiles until its needed,
        # because it triggers an _ensure_real that we otherwise might not need.
        if self._control_files is None:
            self._control_files = RemoteBranchLockableFiles(
                self.bzrdir, self._client)
        return self._control_files

    def _get_checkout_format(self):
        self._ensure_real()
        return self._real_branch._get_checkout_format()

    def get_physical_lock_status(self):
        """See Branch.get_physical_lock_status()."""
        # should be an API call to the server, as branches must be lockable.
        self._ensure_real()
        return self._real_branch.get_physical_lock_status()

    def get_stacked_on_url(self):
        """Get the URL this branch is stacked against.

        :raises NotStacked: If the branch is not stacked.
        :raises UnstackableBranchFormat: If the branch does not support
            stacking.
        :raises UnstackableRepositoryFormat: If the repository does not support
            stacking.
        """
        try:
            # there may not be a repository yet, so we can't use
            # self._translate_error, so we can't use self._call either.
            response = self._client.call('Branch.get_stacked_on_url',
                self._remote_path())
        except errors.ErrorFromSmartServer, err:
            # there may not be a repository yet, so we can't call through
            # its _translate_error
            _translate_error(err, branch=self)
        except errors.UnknownSmartMethod, err:
            self._ensure_real()
            return self._real_branch.get_stacked_on_url()
        if response[0] != 'ok':
            raise errors.UnexpectedSmartServerResponse(response)
        return response[1]

    def lock_read(self):
        self.repository.lock_read()
        if not self._lock_mode:
            self._lock_mode = 'r'
            self._lock_count = 1
            if self._real_branch is not None:
                self._real_branch.lock_read()
        else:
            self._lock_count += 1

    def _remote_lock_write(self, token):
        if token is None:
            branch_token = repo_token = ''
        else:
            branch_token = token
            repo_token = self.repository.lock_write()
            self.repository.unlock()
        err_context = {'token': token}
        response = self._call(
            'Branch.lock_write', self._remote_path(), branch_token,
            repo_token or '', **err_context)
        if response[0] != 'ok':
            raise errors.UnexpectedSmartServerResponse(response)
        ok, branch_token, repo_token = response
        return branch_token, repo_token
            
    def lock_write(self, token=None):
        if not self._lock_mode:
            # Lock the branch and repo in one remote call.
            remote_tokens = self._remote_lock_write(token)
            self._lock_token, self._repo_lock_token = remote_tokens
            if not self._lock_token:
                raise SmartProtocolError('Remote server did not return a token!')
            # Tell the self.repository object that it is locked.
            self.repository.lock_write(
                self._repo_lock_token, _skip_rpc=True)

            if self._real_branch is not None:
                self._real_branch.lock_write(token=self._lock_token)
            if token is not None:
                self._leave_lock = True
            else:
                self._leave_lock = False
            self._lock_mode = 'w'
            self._lock_count = 1
        elif self._lock_mode == 'r':
            raise errors.ReadOnlyTransaction
        else:
            if token is not None:
                # A token was given to lock_write, and we're relocking, so
                # check that the given token actually matches the one we
                # already have.
                if token != self._lock_token:
                    raise errors.TokenMismatch(token, self._lock_token)
            self._lock_count += 1
            # Re-lock the repository too.
            self.repository.lock_write(self._repo_lock_token)
        return self._lock_token or None

    def _unlock(self, branch_token, repo_token):
        err_context = {'token': str((branch_token, repo_token))}
        response = self._call(
            'Branch.unlock', self._remote_path(), branch_token,
            repo_token or '', **err_context)
        if response == ('ok',):
            return
        raise errors.UnexpectedSmartServerResponse(response)

    def unlock(self):
        try:
            self._lock_count -= 1
            if not self._lock_count:
                self._clear_cached_state()
                mode = self._lock_mode
                self._lock_mode = None
                if self._real_branch is not None:
                    if (not self._leave_lock and mode == 'w' and
                        self._repo_lock_token):
                        # If this RemoteBranch will remove the physical lock
                        # for the repository, make sure the _real_branch
                        # doesn't do it first.  (Because the _real_branch's
                        # repository is set to be the RemoteRepository.)
                        self._real_branch.repository.leave_lock_in_place()
                    self._real_branch.unlock()
                if mode != 'w':
                    # Only write-locked branched need to make a remote method
                    # call to perfom the unlock.
                    return
                if not self._lock_token:
                    raise AssertionError('Locked, but no token!')
                branch_token = self._lock_token
                repo_token = self._repo_lock_token
                self._lock_token = None
                self._repo_lock_token = None
                if not self._leave_lock:
                    self._unlock(branch_token, repo_token)
        finally:
            self.repository.unlock()

    def break_lock(self):
        self._ensure_real()
        return self._real_branch.break_lock()

    def leave_lock_in_place(self):
        if not self._lock_token:
            raise NotImplementedError(self.leave_lock_in_place)
        self._leave_lock = True

    def dont_leave_lock_in_place(self):
        if not self._lock_token:
            raise NotImplementedError(self.dont_leave_lock_in_place)
        self._leave_lock = False

    def _last_revision_info(self):
        response = self._call('Branch.last_revision_info', self._remote_path())
        if response[0] != 'ok':
            raise SmartProtocolError('unexpected response code %s' % (response,))
        revno = int(response[1])
        last_revision = response[2]
        return (revno, last_revision)

    def _gen_revision_history(self):
        """See Branch._gen_revision_history()."""
        response_tuple, response_handler = self._call_expecting_body(
            'Branch.revision_history', self._remote_path())
        if response_tuple[0] != 'ok':
            raise errors.UnexpectedSmartServerResponse(response_tuple)
        result = response_handler.read_body_bytes().split('\x00')
        if result == ['']:
            return []
        return result

    def _remote_path(self):
        return self.bzrdir._path_for_remote_call(self._client)

    def _set_last_revision_descendant(self, revision_id, other_branch,
            allow_diverged=False, allow_overwrite_descendant=False):
        err_context = {'other_branch': other_branch}
        response = self._call('Branch.set_last_revision_ex',
            self._remote_path(), self._lock_token, self._repo_lock_token,
            revision_id, int(allow_diverged), int(allow_overwrite_descendant),
            **err_context)
        self._clear_cached_state()
        if len(response) != 3 and response[0] != 'ok':
            raise errors.UnexpectedSmartServerResponse(response)
        new_revno, new_revision_id = response[1:]
        self._last_revision_info_cache = new_revno, new_revision_id
        if self._real_branch is not None:
            cache = new_revno, new_revision_id
            self._real_branch._last_revision_info_cache = cache

    def _set_last_revision(self, revision_id):
        self._clear_cached_state()
        response = self._call('Branch.set_last_revision',
            self._remote_path(), self._lock_token, self._repo_lock_token,
            revision_id)
        if response != ('ok',):
            raise errors.UnexpectedSmartServerResponse(response)

    @needs_write_lock
    def set_revision_history(self, rev_history):
        # Send just the tip revision of the history; the server will generate
        # the full history from that.  If the revision doesn't exist in this
        # branch, NoSuchRevision will be raised.
        if rev_history == []:
            rev_id = 'null:'
        else:
            rev_id = rev_history[-1]
        self._set_last_revision(rev_id)
        self._cache_revision_history(rev_history)

    def get_parent(self):
        self._ensure_real()
        return self._real_branch.get_parent()
        
    def set_parent(self, url):
        self._ensure_real()
        return self._real_branch.set_parent(url)
        
    def set_stacked_on_url(self, stacked_location):
        """Set the URL this branch is stacked against.

        :raises UnstackableBranchFormat: If the branch does not support
            stacking.
        :raises UnstackableRepositoryFormat: If the repository does not support
            stacking.
        """
        self._ensure_real()
        return self._real_branch.set_stacked_on_url(stacked_location)

    def sprout(self, to_bzrdir, revision_id=None):
        branch_format = to_bzrdir._format._branch_format
        if (branch_format is None or
            isinstance(branch_format, RemoteBranchFormat)):
            # The to_bzrdir specifies RemoteBranchFormat (or no format, which
            # implies the same thing), but RemoteBranches can't be created at
            # arbitrary URLs.  So create a branch in the same format as
            # _real_branch instead.
            # XXX: if to_bzrdir is a RemoteBzrDir, this should perhaps do
            # to_bzrdir.create_branch to create a RemoteBranch after all...
            self._ensure_real()
            result = self._real_branch._format.initialize(to_bzrdir)
            self.copy_content_into(result, revision_id=revision_id)
            result.set_parent(self.bzrdir.root_transport.base)
        else:
            result = branch.Branch.sprout(
                self, to_bzrdir, revision_id=revision_id)
        return result

    @needs_write_lock
    def pull(self, source, overwrite=False, stop_revision=None,
             **kwargs):
        self._clear_cached_state_of_remote_branch_only()
        self._ensure_real()
        return self._real_branch.pull(
            source, overwrite=overwrite, stop_revision=stop_revision,
            _override_hook_target=self, **kwargs)

    @needs_read_lock
    def push(self, target, overwrite=False, stop_revision=None):
        self._ensure_real()
        return self._real_branch.push(
            target, overwrite=overwrite, stop_revision=stop_revision,
            _override_hook_source_branch=self)

    def is_locked(self):
        return self._lock_count >= 1

    @needs_read_lock
    def revision_id_to_revno(self, revision_id):
        self._ensure_real()
        return self._real_branch.revision_id_to_revno(revision_id)

    @needs_write_lock
    def set_last_revision_info(self, revno, revision_id):
        revision_id = ensure_null(revision_id)
        try:
            response = self._call('Branch.set_last_revision_info',
                self._remote_path(), self._lock_token, self._repo_lock_token,
                str(revno), revision_id)
        except errors.UnknownSmartMethod:
            self._ensure_real()
            self._clear_cached_state_of_remote_branch_only()
            self._real_branch.set_last_revision_info(revno, revision_id)
            self._last_revision_info_cache = revno, revision_id
            return
        if response == ('ok',):
            self._clear_cached_state()
            self._last_revision_info_cache = revno, revision_id
            # Update the _real_branch's cache too.
            if self._real_branch is not None:
                cache = self._last_revision_info_cache
                self._real_branch._last_revision_info_cache = cache
        else:
            raise errors.UnexpectedSmartServerResponse(response)

    @needs_write_lock
    def generate_revision_history(self, revision_id, last_rev=None,
                                  other_branch=None):
        medium = self._client._medium
        if not medium._is_remote_before((1, 6)):
            try:
                self._set_last_revision_descendant(revision_id, other_branch,
                    allow_diverged=True, allow_overwrite_descendant=True)
                return
            except errors.UnknownSmartMethod:
                medium._remember_remote_is_before((1, 6))
        self._clear_cached_state_of_remote_branch_only()
        self._ensure_real()
        self._real_branch.generate_revision_history(
            revision_id, last_rev=last_rev, other_branch=other_branch)

    @property
    def tags(self):
        self._ensure_real()
        return self._real_branch.tags

    def set_push_location(self, location):
        self._ensure_real()
        return self._real_branch.set_push_location(location)

    @needs_write_lock
    def update_revisions(self, other, stop_revision=None, overwrite=False,
                         graph=None):
        """See Branch.update_revisions."""
        other.lock_read()
        try:
            if stop_revision is None:
                stop_revision = other.last_revision()
                if revision.is_null(stop_revision):
                    # if there are no commits, we're done.
                    return
            self.fetch(other, stop_revision)

            if overwrite:
                # Just unconditionally set the new revision.  We don't care if
                # the branches have diverged.
                self._set_last_revision(stop_revision)
            else:
                medium = self._client._medium
                if not medium._is_remote_before((1, 6)):
                    try:
                        self._set_last_revision_descendant(stop_revision, other)
                        return
                    except errors.UnknownSmartMethod:
                        medium._remember_remote_is_before((1, 6))
                # Fallback for pre-1.6 servers: check for divergence
                # client-side, then do _set_last_revision.
                last_rev = revision.ensure_null(self.last_revision())
                if graph is None:
                    graph = self.repository.get_graph()
                if self._check_if_descendant_or_diverged(
                        stop_revision, last_rev, graph, other):
                    # stop_revision is a descendant of last_rev, but we aren't
                    # overwriting, so we're done.
                    return
                self._set_last_revision(stop_revision)
        finally:
            other.unlock()


def _extract_tar(tar, to_dir):
    """Extract all the contents of a tarfile object.

    A replacement for extractall, which is not present in python2.4
    """
    for tarinfo in tar:
        tar.extract(tarinfo, to_dir)


def _translate_error(err, **context):
    """Translate an ErrorFromSmartServer into a more useful error.

    Possible context keys:
      - branch
      - repository
      - bzrdir
      - token
      - other_branch
      - path

    If the error from the server doesn't match a known pattern, then
    UnknownErrorFromSmartServer is raised.
    """
    def find(name):
        try:
            return context[name]
        except KeyError, key_err:
            mutter('Missing key %r in context %r', key_err.args[0], context)
            raise err
    def get_path():
        """Get the path from the context if present, otherwise use first error
        arg.
        """
        try:
            return context['path']
        except KeyError, key_err:
            try:
                return err.error_args[0]
            except IndexError, idx_err:
                mutter(
                    'Missing key %r in context %r', key_err.args[0], context)
                raise err

    if err.error_verb == 'NoSuchRevision':
        raise NoSuchRevision(find('branch'), err.error_args[0])
    elif err.error_verb == 'nosuchrevision':
        raise NoSuchRevision(find('repository'), err.error_args[0])
    elif err.error_tuple == ('nobranch',):
        raise errors.NotBranchError(path=find('bzrdir').root_transport.base)
    elif err.error_verb == 'norepository':
        raise errors.NoRepositoryPresent(find('bzrdir'))
    elif err.error_verb == 'LockContention':
        raise errors.LockContention('(remote lock)')
    elif err.error_verb == 'UnlockableTransport':
        raise errors.UnlockableTransport(find('bzrdir').root_transport)
    elif err.error_verb == 'LockFailed':
        raise errors.LockFailed(err.error_args[0], err.error_args[1])
    elif err.error_verb == 'TokenMismatch':
        raise errors.TokenMismatch(find('token'), '(remote token)')
    elif err.error_verb == 'Diverged':
        raise errors.DivergedBranches(find('branch'), find('other_branch'))
    elif err.error_verb == 'TipChangeRejected':
        raise errors.TipChangeRejected(err.error_args[0].decode('utf8'))
    elif err.error_verb == 'UnstackableBranchFormat':
        raise errors.UnstackableBranchFormat(*err.error_args)
    elif err.error_verb == 'UnstackableRepositoryFormat':
        raise errors.UnstackableRepositoryFormat(*err.error_args)
    elif err.error_verb == 'NotStacked':
        raise errors.NotStacked(branch=find('branch'))
    elif err.error_verb == 'PermissionDenied':
        path = get_path()
        if len(err.error_args) >= 2:
            extra = err.error_args[1]
        else:
            extra = None
        raise errors.PermissionDenied(path, extra=extra)
    elif err.error_verb == 'ReadError':
        path = get_path()
        raise errors.ReadError(path)
    elif err.error_verb == 'NoSuchFile':
        path = get_path()
        raise errors.NoSuchFile(path)
    elif err.error_verb == 'FileExists':
        raise errors.FileExists(err.error_args[0])
    elif err.error_verb == 'DirectoryNotEmpty':
        raise errors.DirectoryNotEmpty(err.error_args[0])
    elif err.error_verb == 'ShortReadvError':
        args = err.error_args
        raise errors.ShortReadvError(
            args[0], int(args[1]), int(args[2]), int(args[3]))
    elif err.error_verb in ('UnicodeEncodeError', 'UnicodeDecodeError'):
        encoding = str(err.error_args[0]) # encoding must always be a string
        val = err.error_args[1]
        start = int(err.error_args[2])
        end = int(err.error_args[3])
        reason = str(err.error_args[4]) # reason must always be a string
        if val.startswith('u:'):
            val = val[2:].decode('utf-8')
        elif val.startswith('s:'):
            val = val[2:].decode('base64')
        if err.error_verb == 'UnicodeDecodeError':
            raise UnicodeDecodeError(encoding, val, start, end, reason)
        elif err.error_verb == 'UnicodeEncodeError':
            raise UnicodeEncodeError(encoding, val, start, end, reason)
    elif err.error_verb == 'ReadOnlyError':
        raise errors.TransportNotPossible('readonly transport')
    raise errors.UnknownErrorFromSmartServer(err)