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
|
# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
# file, You can obtain one at http://mozilla.org/MPL/2.0/.
import os
import time
import zipfile
import six
from mozbuild.lock import lock_file
class ZipFile(zipfile.ZipFile):
"""Class with methods to open, read, write, close, list zip files.
Subclassing zipfile.ZipFile to allow for overwriting of existing
entries, though only for writestr, not for write.
"""
def __init__(self, file, mode="r", compression=zipfile.ZIP_STORED, lock=False):
if lock:
assert isinstance(file, six.text_type)
self.lockfile = lock_file(file + ".lck")
else:
self.lockfile = None
if mode == "a" and lock:
# appending to a file which doesn't exist fails, but we can't check
# existence util we hold the lock
if (not os.path.isfile(file)) or os.path.getsize(file) == 0:
mode = "w"
zipfile.ZipFile.__init__(self, file, mode, compression)
self._remove = []
self.end = self.fp.tell()
self.debug = 0
def writestr(self, zinfo_or_arcname, bytes):
"""Write contents into the archive.
The contents is the argument 'bytes', 'zinfo_or_arcname' is either
a ZipInfo instance or the name of the file in the archive.
This method is overloaded to allow overwriting existing entries.
"""
if not isinstance(zinfo_or_arcname, zipfile.ZipInfo):
zinfo = zipfile.ZipInfo(
filename=zinfo_or_arcname, date_time=time.localtime(time.time())
)
zinfo.compress_type = self.compression
# Add some standard UNIX file access permissions (-rw-r--r--).
zinfo.external_attr = (0x81A4 & 0xFFFF) << 16
else:
zinfo = zinfo_or_arcname
# Now to the point why we overwrote this in the first place,
# remember the entry numbers if we already had this entry.
# Optimizations:
# If the entry to overwrite is the last one, just reuse that.
# If we store uncompressed and the new content has the same size
# as the old, reuse the existing entry.
doSeek = False # store if we need to seek to the eof after overwriting
if zinfo.filename in self.NameToInfo:
# Find the last ZipInfo with our name.
# Last, because that's catching multiple overwrites
i = len(self.filelist)
while i > 0:
i -= 1
if self.filelist[i].filename == zinfo.filename:
break
zi = self.filelist[i]
if (
zinfo.compress_type == zipfile.ZIP_STORED
and zi.compress_size == len(bytes)
) or (i + 1) == len(self.filelist):
# make sure we're allowed to write, otherwise done by writestr below
self._writecheck(zi)
# overwrite existing entry
self.fp.seek(zi.header_offset)
if (i + 1) == len(self.filelist):
# this is the last item in the file, just truncate
self.fp.truncate()
else:
# we need to move to the end of the file afterwards again
doSeek = True
# unhook the current zipinfo, the writestr of our superclass
# will add a new one
self.filelist.pop(i)
self.NameToInfo.pop(zinfo.filename)
else:
# Couldn't optimize, sadly, just remember the old entry for removal
self._remove.append(self.filelist.pop(i))
zipfile.ZipFile.writestr(self, zinfo, bytes)
self.filelist.sort(key=lambda l: l.header_offset)
if doSeek:
self.fp.seek(self.end)
self.end = self.fp.tell()
def close(self):
"""Close the file, and for mode "w" and "a" write the ending
records.
Overwritten to compact overwritten entries.
"""
if not self._remove:
# we don't have anything special to do, let's just call base
r = zipfile.ZipFile.close(self)
self.lockfile = None
return r
if self.fp.mode != "r+b":
# adjust file mode if we originally just wrote, now we rewrite
self.fp.close()
self.fp = open(self.filename, "r+b")
all = map(lambda zi: (zi, True), self.filelist) + map(
lambda zi: (zi, False), self._remove
)
all.sort(key=lambda l: l[0].header_offset)
# empty _remove for multiple closes
self._remove = []
lengths = [
all[i + 1][0].header_offset - all[i][0].header_offset
for i in xrange(len(all) - 1)
]
lengths.append(self.end - all[-1][0].header_offset)
to_pos = 0
for (zi, keep), length in zip(all, lengths):
if not keep:
continue
oldoff = zi.header_offset
# python <= 2.4 has file_offset
if hasattr(zi, "file_offset"):
zi.file_offset = zi.file_offset + to_pos - oldoff
zi.header_offset = to_pos
self.fp.seek(oldoff)
content = self.fp.read(length)
self.fp.seek(to_pos)
self.fp.write(content)
to_pos += length
self.fp.truncate()
zipfile.ZipFile.close(self)
self.lockfile = None
|
