summaryrefslogtreecommitdiff
blob: e157d23835481caa643db6f613919e588cbb812c (plain)
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
#!/usr/bin/python -O
#
# /usr/sbin/webapp-config
#       Python script for managing the deployment of web-based
#       applications
#
#       Originally written for the Gentoo Linux distribution
#
# Copyright (c) 1999-2007 Authors
#       Released under v2 of the GNU GPL
#
# Author(s)     Stuart Herbert
#               Renat Lumpau   <rl03@gentoo.org>
#               Gunnar Wrobel  <wrobel@gentoo.org>
#
# ========================================================================
''' This class handles the contents file of a virtual install
location.  This file records all files and directories of the
installation.  '''

# ========================================================================
# Dependencies
# ------------------------------------------------------------------------

import hashlib, re, os, os.path

from WebappConfig.debug       import OUT
from WebappConfig.permissions import PermissionMap
from WebappConfig.compat      import create_md5
# ========================================================================
# Content handler
# ------------------------------------------------------------------------

class Contents:
    '''
    This class records the contents for virtual install locations.
    '''

#self.worker.get_config('g_perms_dotconfig')
    def __init__(self,
                 installdir,
                 category   = '',
                 package    = '',
                 version    = '',
                 permission = PermissionMap('0600'),
                 dbfile     = '.webapp',
                 verbose    = False,
                 pretend    = False,
                 root       = ''):

        self.__root       = root
        self.__re         = re.compile('/+')
        self.__installdir = installdir

        self.__cat        = category
        self.__pn         = package
        self.__pvr        = version
        self.__dbfile     = dbfile

        self.__perm = permission
        self.__v    = verbose
        self.__p    = pretend

        self.__content = {}

        # Ignore specific files while removing contents

        # Added "webapp-test" to the list of ignored files. This
        # type of file will be used to mark directories that should
        # be included into the distutils manifest.
        self.ignore = ['webapp_test']

    def package_name(self):
        ''' Return the package name for the virtual install.'''
        if self.__cat:
            # use _ instead of / because we don't want to create a directory
            return self.__cat + '_' + self.__pn + '-' + self.__pvr
        else:
            return self.__pn + '-' + self.__pvr

    def set_category(self, cat):
        ''' Set category name.'''
        self.__cat = cat

    def set_package(self, package):
        ''' Set the package name.'''
        self.__pn = package

    def set_version(self, version):
        ''' Set the package version.'''
        self.__pvr = version

    def appdb(self):
        ''' Return the full path to the contents file.'''
        return self.__installdir + '/' + self.__dbfile + '-' \
            + self.package_name()

    def db_print(self):
        ''' Print all enties of the contents file.'''
        entries = self.get_sorted_files()
        values = []
        for i in entries:
            # Fix relative entry
            s = self.__content[i]
            s[1] = str(int(s[1]))
            values.append(' '.join(s))
        OUT.notice('\n'.join(values))

    def check_installdir(self):
        if not os.path.isdir(self.__installdir) and not self.__p:
            OUT.die('"' + self.__installdir + '" specifies no directory! '
                    'webapp-config needs a valid directory to store/retri'
                    'eve information. Please correct your settings.')

    def kill(self):
        ''' Remove the contents file.'''
        if not self.__p:
            try:
                dbpath = self.appdb()
                self.check_installdir()
                os.unlink(dbpath)
                self.__content = {}
                return True
            except:
                OUT.warn('Failed to remove ' + self.appdb() + '!')
                return False
        else:
            OUT.info('Would have removed ' + self.appdb())
            return True

    def read(self):
        '''
        Reads the contents database.

        Some content files have been provided for test purposes:

        >>> import os.path
        >>> here = os.path.dirname(os.path.realpath(__file__))

        This one should succeed:

        >>> a = Contents(here + '/tests/testfiles/contents/',
        ...              package = 'test', version = '1.0')
        >>> a.read()
        >>> a.db_print()
        file 1 virtual util/icon_browser.php 1124612216 9ffb2ca9ccd2db656b97cd26a1b06010 
        file 1 config-owned inc/prefs.php 1124612215 ffae752dba7092cd2d1553d04a0f0045 
        file 1 virtual lib/prefs.php 1124612215 ffae752dba7092cd2d1553d04a0f0045 
        file 1 virtual signup.php 1124612220 dc838bc375b3d02dafc414f8e71a2aec 
        file 1 server-owned data.php 1117009618 0 
        sym 1 virtual test 1124612220 dc838bc375b3d02dafc414f8e71a2aec /I link / to a very / strange location
        dir 1 default-owned util 1117009618 0 
        dir 1 config-owned inc 1117009618 0 
        dir 1 default-owned lib 1117009618 0 
        dir 0 default-owned /var/www/localhost/cgi-bin 1124577741 0 
        dir 0 default-owned /var/www/localhost/error 1124577740 0 
        dir 0 default-owned /var/www/localhost/icons 1124577741 0 
        
        >>> a.get_directories() #doctest: +ELLIPSIS
        ['.../contents//util', '.../contents//inc', '.../contents//lib', '/var/www/localhost/cgi-bin', '/var/www/localhost/error', '/var/www/localhost/icons']

        This is a corrupted file that checks all fail safes:

        >>> OUT.color_off()
        >>> a = Contents(here + '/tests/testfiles/contents/',
        ...              package = 'test', version = '1.1')
        >>> a.read() #doctest: +ELLIPSIS
        * Invalid line in content file (dir 1 default-owned). Ignoring!
        * Content file .../tests/testfiles/contents//.webapp-test-1.1 has an invalid line:
        * dir 1 nobody-owned  1117009618 0
        * Invalid owner: nobody-owned
        * Invalid line in content file (dir 1 nobody-owned  1117009618 0). Ignoring!
        * Content file .../tests/testfiles/contents//.webapp-test-1.1 has an invalid line:
        * garbage 1 virtual  1124612215 ffae752dba7092cd2d1553d04a0f0045
        * Invalid file type: garbage
        * Invalid line in content file (garbage 1 virtual  1124612215 ffae752dba7092cd2d1553d04a0f0045). Ignoring!
        * Invalid line in content file (file 1 virtual). Ignoring!
        * Content file .../tests/testfiles/contents//.webapp-test-1.1 has an invalid line:
        * file 1 virtual 
        * Not enough entries.
        * Invalid line in content file (file 1 virtual ). Ignoring!
        * Content file .../tests/testfiles/contents//.webapp-test-1.1 has an invalid line:
        * file 31 config-owned  1124612215 ffae752dba7092cd2d1553d04a0f0045
        * Invalid relative flag: 31
        * Invalid line in content file (file 31 config-owned  1124612215 ffae752dba7092cd2d1553d04a0f0045). Ignoring!
        '''

        dbpath = self.appdb()

        if not dbpath or not os.access(dbpath, os.R_OK):
            OUT.die('Content file ' + dbpath + ' is missing or not accessibl'
                    'e!')

        content = open(dbpath).readlines()

        for i in content:

            i = i.strip()

            rfn = re.compile('"(.*)"')
            rfs = rfn.search(i)
            if not rfs:
                ok = False
            else:
                fn  = rfs.group(1)
                i   = rfn.sub('', i)
                line_split = i.split(' ')
                line_split[3] = fn

                OUT.debug('Adding content line', 10)

                ok = True

                if len(line_split) < 6:
                    ok = False
                    OUT.warn('Content file ' + dbpath + ' has an invalid line'
                             ':\n' + i + '\nNot enough entries.')

                if ok and not line_split[0] in ['file', 'sym', 'dir']:
                    ok = False
                    OUT.warn('Content file ' + dbpath + ' has an invalid line'
                             ':\n' + i + '\nInvalid file type: '
                             + line_split[0])

                if ok and not line_split[1] in ['0', '1']:
                    ok = False
                    OUT.warn('Content file ' + dbpath + ' has an invalid line'
                             ':\n' + i + '\nInvalid relative flag: '
                             + line_split[1])

                if ok and not line_split[2] in ['virtual',
                                                'server-owned',
                                                'config-owned',
                                                'default-owned',
                                                'config-server-owned',
                                                # Still need that in case an 
                                                # application was installed
                                                # with w-c-1.11
                                                'root-owned']:
                    ok = False
                    OUT.warn('Content file ' + dbpath + ' has an invalid line'
                             ':\n' + i + '\nInvalid owner: '
                             + line_split[2])

                if ok and line_split[0] == 'sym' and len(line_split) == 6:
                    OUT.warn('Content file ' + dbpath + ' has an invalid line'
                             ':\n' + i + '\nMissing link target! ')

                if len(line_split) == 6:
                    line_split.append('')

                # I think this could happen if the link target contains
                # spaces
                # -- wrobel
                if len(line_split) > 7:
                    line_split = line_split[0:6]                         \
                                 + [' '.join(line_split[6:])]

            if ok:
                if line_split[1] == '0':
                    self.__content[line_split[3]] = line_split
                else:
                    self.__content[self.__installdir + '/'
                                   + line_split[3]] = line_split

            else:
                OUT.warn('Invalid line in content file (' + i + '). Ignor'
                         'ing!')

    def write(self):
        '''
        Write the contents file.

        A short test:

        >>> import os.path
        >>> here = os.path.dirname(os.path.realpath(__file__))
        >>> a = Contents(here + '/tests/testfiles/contents/',
        ...              package = 'test', version = '1.0',
        ...              pretend = True)
        >>> a.read()
        >>> OUT.color_off()
        >>> a.write() #doctest: +ELLIPSIS
        * Would have written content file .../tests/testfiles/contents//.webapp-test-1.0!
        '''

        dbpath = self.appdb()

        if not dbpath:
            OUT.die('No package specified!')

        self.check_installdir()

        values = [' '.join(i) for i in list(self.__content.values())]

        if not self.__p:
            try:
                fd = os.open(self.appdb(), os.O_WRONLY | os.O_CREAT,
                             self.__perm(0o600))

                os.write(fd, ('\n'.join(values)).encode('utf-8'))

                os.close(fd)
            except Exception as e:
                OUT.warn('Failed to write content file ' + dbpath + '!\n' 
                         + 'Error was: ' + str(e))
        else:
            OUT.info('Would have written content file ' + dbpath + '!')

    def delete(self, entry):
        '''
        Delete a database entry.
        '''
        del self.__content[entry]

    def add(self,
            dsttype,
            ctype,
            destination,
            path,
            real_path,
            relative = True):
        '''
        Add an entry to the contents file.

        Just like Portage, when we install an app, we create a contents
        file to say what we installed and when.  We use this contents
        file to help us safely remove & upgrade apps.

        CONTENTS file format:

        <what> <rel> <type> <filename> <timestamp> <sum> [<optional>]

        where

        <what>      is one of dir|sym|file|hardlink

        <rel>       is 1 for relative filenames, 0 for absolute
                        filenames

        <type>      is one of
                        server-owned|default-owned|config-owned|virtual

        <timestamp> is the timestamp when the file was installed

        <sum>       is the md5sum of the file
                        (this is 0 for directories and symlinks)

        <filename>      is the actual name of the file we have installed

        <optional>      is additional data that depends upon <what>

        NOTE:
            Filenames used to be on the end of the line.  This made
                the old bash version more complicated, and
                prone to failure. So I have moved the filename into the
                middle of the line. -- Stuart

        Portage uses absolute names for its files, dirs, and symlinks.
        We do not.
        In theory, you can move a directory containing a web-based app,
        and

        a) the app itself will not break, and
        b) webapp-config will still work on that directory
           for upgrades and cleans.

        Position-independence *is* a design constraint that all future
        changes to this script need to honour.

        Inputs:

          dsttype     - type to add (one of dir|sym|file|hardlink)
          ctype       - internal webapp-config type
                      - (server-owned | config-owned | virtual)
          destination - install dir (normally $G_INSTALLDIR)
          path        - filename inside 'destination'
          real_path   - for config-protected files realpath =! path
                        (and this is important for md5)
          relative    - 1 for storing a relative filename, 0 otherwise

        OUT.color_off()
        import os.path
        here = os.path.dirname(os.path.realpath(__file__))

        One for pretending:

        a = Contents(here + '/tests/testfiles/contents/app/',
        ...              package = 'test', version = '1.0',
        ...              pretend = True)

        And this one is for real:

        b = Contents(here + '/tests/testfiles/contents/app/',
        ...              package = 'test', version = '1.0')

        Pretend to add a file:

        a.add('file', 'config-owned',
        ...       destination = here + '/tests/testfiles/contents/app/',
        ...       path = '/test1', relative = True)
        *     pretending to add: file 1 config-owned "test1"

        Lets not pretend this time:

        b.add('file', 'config-owned',
        ...       destination = here + '/tests/testfiles/contents/app/',
        ...       path = '/test1', relative = True)
        b.entry(here + '/tests/testfiles/contents/app/test1') #doctest: +ELLIPSIS
        'file 1 config-owned "test1" ... d8e8fca2dc0f896fd7cb4cb0031ba249 '

        Lets produce an error with a file that does not exist:

        b.add('file', 'config-owned',
        ...       destination = here + '/tests/testfiles/contents/app/',
        ...       path = '/nothere', relative = True) #doctest: +ELLIPSIS
        * Cannot access file .../tests/testfiles/contents/app/nothere to add it as installation content. This should not happen!

        Other file types:

        b.add('hardlink', 'config-owned',
        ...       destination = here + '/tests/testfiles/contents/app/',
        ...       path = '/test2', relative = True)
        b.entry(here + '/tests/testfiles/contents/app/test2') #doctest: +ELLIPSIS
        'file 1 config-owned "test2" ... d8e8fca2dc0f896fd7cb4cb0031ba249 '
        b.add('dir', 'default-owned',
        ...       destination = here + '/tests/testfiles/contents/app/',
        ...       path = '/dir1', relative = True)
        b.entry(here + '/tests/testfiles/contents/app/dir1') #doctest: +ELLIPSIS
        'dir 1 default-owned "dir1" ... 0 '
        b.add('dir', 'default-owned', destination = here + '/tests/testfiles/contents/app',
        ...       path = '/dir1',
        ...       relative = False)
        b.entry(here + '/tests/testfiles/contents/app/dir1') #doctest: +ELLIPSIS
        'dir 0 default-owned ".../tests/testfiles/contents/app/dir1" ... 0 '

        Q: Is the full link to the target what we want?
        A: Yes, since the link will still be ok even if we move the directory.

        b.add('sym', 'virtual',
        ...       destination = here + '/tests/testfiles/contents/app/',
        ...       path = '/test3', relative = True)
        b.entry(here + '/tests/testfiles/contents/app/test3') #doctest: +ELLIPSIS
        'sym 1 virtual "test3" ... 0 .../tests/testfiles/contents/app/test1'

        b.db_print() #doctest: +ELLIPSIS
        file 1 config-owned "test1" ... d8e8fca2dc0f896fd7cb4cb0031ba249 
        file 1 config-owned "test2" ... d8e8fca2dc0f896fd7cb4cb0031ba249 
        sym 1 virtual "test3" ... 0 .../tests/testfiles/contents/app/test1
        dir 0 default-owned ".../tests/testfiles/contents/app/dir1" ... 0 

        '''

        OUT.debug('Adding entry to content dictionary', 6)

        # Build the full path that we use as index in the contents list
        while path[0] == '/':
            path = path[1:]
        while destination[-1] == '/':
            destination = destination[:-1]

        entry = destination + '/' + path

        # special case - we don't add entries for '.'

        if os.path.basename(entry) == '.':
            return

        if (not self.__p
                and not os.path.islink(entry)
                and (not os.path.exists(entry)
                    or not os.access(entry, os.R_OK))):
            OUT.warn('Cannot access file ' + entry + ' to add it as'
                     ' installation content. This should not happen!')
            return

        allowed_types = {
            'file'    : [ 'file', self.file_md5,  self.file_null ],
            'hardlink': [ 'file', self.file_md5,  self.file_null ],
            'dir'     : [  'dir', self.file_zero, self.file_null ],
            'sym'     : [  'sym', self.file_zero, self.file_link ],
            }

        if not dsttype in list(allowed_types.keys()):
            OUT.die('Oops, webapp-config bug. "dsttype" is ' + dsttype)

        # Generate handler for file attributes
        a = allowed_types[dsttype]

        # For absolute entries the path must match the entry
        if not relative:
            path = entry

        OUT.debug('Adding entry', 7)

        # report if pretending
        if self.__p:

            OUT.info('    pretending to add: ' +
                     ' '.join([dsttype,
                               str(int(relative)),
                               ctype,
                               '"' + path + '"']))
        else:

            # Only the path is enclosed in quotes, NOT the link targets
            self.__content[entry] = [ a[0],
                                      str(int(relative)),
                                      ctype,
                                      '"' + path + '"',
                                      self.file_time(entry),
                                      a[1](real_path),
                                      a[2](entry)]

            if self.__v:
                msg = path
                if msg[0] == "/":
                    msg = self.__root + msg
                    msg = self.__re.sub('/', msg)
                OUT.notice('>>> ' + a[0] + ' ' * (4 - len(a[0])) + ' ('  \
                           + ctype + ') ' + msg)


    def file_zero(self, filename):
        ''' Just return a zero value.'''
        return '0'

    def file_null(self, filename):
        ''' Just return an empty value.'''
        return ''

    def file_md5(self, filename):
        ''' Return the md5 hash for the file content.'''
        return create_md5(filename)

    def file_time(self, filename):
        ''' Return the last modification time.'''
        if os.path.islink(filename):
            return str(os.lstat(filename)[8])
        else:
            return str(os.stat(filename)[8])

    def file_link(self, filename):
        ''' Return the path of the link target.'''
        return os.path.realpath(filename)

    def get_sorted_files(self):
        ''' Get a list of files. This is returned as a list sorted according
        to length, so that files lower in the hierarchy can be removed
        first.'''
        installed = list(self.__content.keys())
        return sorted(installed, key=lambda x: (-len(x), x))

    def get_directories(self):
        ''' Get only the directories as a sorted list.'''
        return [i
                for i in self.get_sorted_files()
                if self.__content[i][0] == 'dir']

    def get_files(self):
        ''' Get only files as a sorted list.'''
        return [i
                for i in self.get_sorted_files()
                if self.__content[i][0] in ['sym', 'file']]


    def get_canremove(self, entry):
        '''
        Determines if an entry can be removed.

        Returns a string if the entry may not be removed. The
        string will describe the reason why the entry should
        not be removed.

        In case the entry can be removed nothing will be
        returned.

        >>> import os.path
        >>> here = os.path.dirname(os.path.realpath(__file__))

        Trying to remove the contents:

        >>> a = Contents(here + '/tests/testfiles/contents/app/',
        ...              package = 'test', version = '1.0')
        >>> a.read()
        >>> a.ignore += ['.svn']
        >>> for i in a.get_directories():
        ...     a.get_canremove(i)
        '!dir test7'
        '!empty dir1'

        >>> for i in a.get_files():
        ...     a.get_canremove(i)
        '!time test2'
        '!time test4'
        '!found test6'
        '!sym dir3'
        '!file dir4'

        # Disabled 
        #'!target test3'

        '''

        OUT.debug('Checking if the file can be removed', 6)

        # Path not found.
        # Cannot remove -> return False
        if not os.path.exists(entry) and not os.path.islink(entry):

            OUT.debug('Did not find the file.', 7)

            return '!found ' + self.epath(entry)

        entry_type = self.etype(entry)

        if entry_type == 'sym':
            # Should be a link but is not.
            if not os.path.islink(entry):
                return '!sym ' + self.epath(entry)

            # Expected link location does not match with
            # current target.
            # this results in leaving broken symlinks behind
            # if self.file_link(entry) != self.etarget(entry):
            #     return '!target ' + self.epath(entry)

        if entry_type == 'file':

            # Expected file, path is not a file
            if not os.path.isfile(entry):
                return '!file ' + self.epath(entry)

            # This is config protected. Do not remove!
            #if self.eowner(entry)[0:6] == 'config':
            #    return '!cfgpro ' + self.epath(entry)

            # Modification time does not match. Refuse to remove.
            if self.file_time(entry) != self.etime(entry):
                return '!time ' + self.epath(entry)

            # Content has different hash. Do not remove.
            if self.file_md5(entry) != self.emd5(entry):
                return '!sum ' + self.epath(entry)

        if entry_type == 'dir':

            # Expected directory, path is not a directory.
            if not os.path.isdir(entry):
                return '!dir ' + self.epath(entry)

            # the rules are simple
            #
            # if the directory is empty, it can go
            # if the directory is not empty, it cannot go

            # get a directory listing

            entry_list = os.listdir(entry)

            # Support for ignoring file. Currently only needed
            # to enable doctests in the subversion repository
            if self.ignore:
                entry_list = [i for i in  entry_list
                              if not i in self.ignore]

            OUT.debug('Remaining files', 7)

            # Directory not empty
            # Cannot remove -> return False
            if entry_list:
                return '!empty ' + self.epath(entry)

        # All checks passed? Remove!

    def entry(self, entry):
        ''' Return a complete entry.'''
        if entry in list(self.__content.keys()):
            return ' '.join(self.__content[entry])
        else:
            raise Exception('Unknown file "' + entry + '"')

    def etype(self, entry):
        '''
        Returns the entry type.
        '''
        if entry in list(self.__content.keys()):
            return self.__content[entry][0]
        else:
            raise Exception('Unknown file "' + entry + '"')

    def erelative(self, entry):
        '''
        Returns if the entry is relative or not.
        '''
        if entry in list(self.__content.keys()):
            return bool(int(self.__content[entry][1]))
        else:
            raise Exception('Unknown file "' + entry + '"')

    def eowner(self, entry):
        '''
        Returns the owner of the entry.
        '''
        if entry in list(self.__content.keys()):
            return self.__content[entry][2]
        else:
            raise Exception('Unknown file "' + entry + '"')

    def epath(self, entry):
        '''
        Returns the (possibly relative) path of the entry.
        '''
        if entry in list(self.__content.keys()):
            msg = self.__content[entry][3]
            if msg[0] == "/":
                msg = self.__root + msg
                msg = self.__re.sub('/', msg)
            return msg
        else:
            raise Exception('Unknown file "' + entry + '"')

    def etime(self, entry):
        '''
        Returns the recorded modification time of the entry.
        '''
        if entry in list(self.__content.keys()):
            return self.__content[entry][4]
        else:
            raise Exception('Unknown file "' + entry + '"')

    def emd5(self, entry):
        '''
        Returns the recorded md5 hash of the entry.
        '''
        if entry in list(self.__content.keys()):
            return self.__content[entry][5]
        else:
            raise Exception('Unknown file "' + entry + '"')

    def etarget(self, entry):
        '''
        Returns the recorded target of the link.
        '''
        if entry in list(self.__content.keys()):
            return self.__content[entry][6]
        else:
            raise Exception('Unknown file "' + entry + '"')

if __name__ == '__main__':
    import doctest, sys
    doctest.testmod(sys.modules[__name__])