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
|
"""
@copyright: 2009 Bastian Blank <waldi@debian.org>
@license: GNU GPL-3
"""
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License version 3 as
# published by the Free Software Foundation.
#
# 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, see <http://www.gnu.org/licenses/>.
import struct
from .general import DescriptorTag, OSTACompressedUnicode, LongAD, ShortAD
class LongADPartition(LongAD):
def __init__(self, buf, volume):
super().__init__(buf)
partition = volume.partitions[self.partition]
self.location_absolute = partition.location + self.location
class ShortADPartition(ShortAD):
def __init__(self, buf, volume, partition_nr):
super().__init__(buf)
partition = volume.partitions[partition_nr]
self.location_absolute = partition.location + self.location
class ICBTag:
_struct = struct.Struct('<8x3xB6xH')
def __init__(self, buf):
data = self._struct.unpack(buf)
self.filetype, self.flags = data
def __repr__(self):
return '<ICBTag with filetype: %d; flags: %x>' % (
self.filetype,
self.flags,
)
class FileSet:
_lazy = 'root',
_struct = struct.Struct('<16x384x16s')
def __init__(self, media, volume, partition_nr, tag, buf):
self._media = media
self._volume = volume
self._partition_nr = partition_nr
self.tag = tag
if tag.identifier != 256:
raise RuntimeError
data = self._struct.unpack(buf[:416])
self.root_icb = LongADPartition(data[0], volume)
def __getattr__(self, key):
if key in self._lazy:
self._populate()
return super().__getattribute__(key)
def _populate(self):
location = self.root_icb.location_absolute
length = self.root_icb.length
buf = self._media.read_sector(location, length)
tag = DescriptorTag(buf)
self.root = FileEntry(self._media, self._volume, self._partition_nr, tag, buf)
class FileEntry:
_lazy = 'tree',
_struct = struct.Struct('<16x20s20xQ104xII')
def __init__(self, media, volume, partition_nr, tag, buf):
self._media = media
self._volume = volume
self._partition_nr = partition_nr
self.tag = tag
if tag.identifier != 261:
raise RuntimeError
data = self._struct.unpack(buf[:176])
icb, self.length, length_ea, length_ad = data
self.icb = ICBTag(icb)
ad = []
buf = buf[176 + length_ea:176 + length_ea + length_ad]
desc_type = self.icb.flags & 3
cur = 0
while cur < len(buf):
if desc_type == 0:
ad.append(ShortADPartition(buf[cur:cur + ShortAD.size], self._volume, self._partition_nr))
cur += ShortAD.size
else:
raise NotImplementedError
self.ad = tuple(ad)
def __getattr__(self, key):
if key in self._lazy:
self._populate()
return super().__getattribute__(key)
def __repr__(self):
return '<FileEntry with icbtag: %r; ad: %r>' % (
self.icb,
self.ad,
)
def _populate(self):
tree = None
if self.icb.filetype == 4:
tree = {}
for ad in self.ad:
location = ad.location_absolute
length = ad.length
buf = self._media.read_sector(location, length)
tag = DescriptorTag(buf)
cur = 0
while cur < length:
if tag.identifier == 257:
f = FileIdentifier(self._media, self._volume, self._partition_nr, tag, buf[cur:])
tree[f.name] = f
cur += f.descriptor_length
else:
raise RuntimeError
else:
raise NotImplementedError
self.tree = tree
class FileIdentifier:
_lazy = 'entry',
_struct = struct.Struct('<16x3xB16sH')
def __init__(self, media, volume, partition_nr, tag, buf):
self._media = media
self._volume = volume
self._partition_nr = partition_nr
self.tag = tag
if tag.identifier != 257:
raise RuntimeError
data = self._struct.unpack(buf[:38])
length_fi, icb, length_iu = data
self.icb = LongADPartition(icb, volume)
# From libdvdread
self.descriptor_length = 4 * ((38 + length_fi + length_iu + 3) // 4)
if length_fi:
self.name = OSTACompressedUnicode(buf[38 + length_iu:38 + length_iu + length_fi])
else:
self.name = ''
def __getattr__(self, key):
if key in self._lazy:
self._populate()
return super().__getattribute__(key)
def __repr__(self):
return '<FileIdentifier with name: %r>' % (
self.name,
)
def _populate(self):
location = self.icb.location_absolute
length = self.icb.length
buf = self._media.read_sector(location, length)
tag = DescriptorTag(buf)
self.entry = FileEntry(self._media, self._volume, self._partition_nr, tag, buf)
|
