Origin: http://svn.python.org/projects/python/branches/release26-maint/Lib/zipfile.py
Date: 2009-11-30
--- /dev/null
+++ b/epubview/zipfile.py
@@ -0,0 +1,1406 @@
+"""
+Read and write ZIP files.
+"""
+import struct, os, time, sys, shutil
+import binascii, cStringIO, stat
+
+try:
+    import zlib # We may need its compression method
+    crc32 = zlib.crc32
+except ImportError:
+    zlib = None
+    crc32 = binascii.crc32
+
+__all__ = ["BadZipfile", "error", "ZIP_STORED", "ZIP_DEFLATED", "is_zipfile",
+           "ZipInfo", "ZipFile", "PyZipFile", "LargeZipFile" ]
+
+class BadZipfile(Exception):
+    pass
+
+
+class LargeZipFile(Exception):
+    """
+    Raised when writing a zipfile, the zipfile requires ZIP64 extensions
+    and those extensions are disabled.
+    """
+
+error = BadZipfile      # The exception raised by this module
+
+ZIP64_LIMIT = (1 << 31) - 1
+ZIP_FILECOUNT_LIMIT = 1 << 16
+ZIP_MAX_COMMENT = (1 << 16) - 1
+
+# constants for Zip file compression methods
+ZIP_STORED = 0
+ZIP_DEFLATED = 8
+# Other ZIP compression methods not supported
+
+# Below are some formats and associated data for reading/writing headers using
+# the struct module.  The names and structures of headers/records are those used
+# in the PKWARE description of the ZIP file format:
+#     http://www.pkware.com/documents/casestudies/APPNOTE.TXT
+# (URL valid as of January 2008)
+
+# The "end of central directory" structure, magic number, size, and indices
+# (section V.I in the format document)
+structEndArchive = "<4s4H2LH"
+stringEndArchive = "PK\005\006"
+sizeEndCentDir = struct.calcsize(structEndArchive)
+
+_ECD_SIGNATURE = 0
+_ECD_DISK_NUMBER = 1
+_ECD_DISK_START = 2
+_ECD_ENTRIES_THIS_DISK = 3
+_ECD_ENTRIES_TOTAL = 4
+_ECD_SIZE = 5
+_ECD_OFFSET = 6
+_ECD_COMMENT_SIZE = 7
+# These last two indices are not part of the structure as defined in the
+# spec, but they are used internally by this module as a convenience
+_ECD_COMMENT = 8
+_ECD_LOCATION = 9
+
+# The "central directory" structure, magic number, size, and indices
+# of entries in the structure (section V.F in the format document)
+structCentralDir = "<4s4B4HL2L5H2L"
+stringCentralDir = "PK\001\002"
+sizeCentralDir = struct.calcsize(structCentralDir)
+
+# indexes of entries in the central directory structure
+_CD_SIGNATURE = 0
+_CD_CREATE_VERSION = 1
+_CD_CREATE_SYSTEM = 2
+_CD_EXTRACT_VERSION = 3
+_CD_EXTRACT_SYSTEM = 4
+_CD_FLAG_BITS = 5
+_CD_COMPRESS_TYPE = 6
+_CD_TIME = 7
+_CD_DATE = 8
+_CD_CRC = 9
+_CD_COMPRESSED_SIZE = 10
+_CD_UNCOMPRESSED_SIZE = 11
+_CD_FILENAME_LENGTH = 12
+_CD_EXTRA_FIELD_LENGTH = 13
+_CD_COMMENT_LENGTH = 14
+_CD_DISK_NUMBER_START = 15
+_CD_INTERNAL_FILE_ATTRIBUTES = 16
+_CD_EXTERNAL_FILE_ATTRIBUTES = 17
+_CD_LOCAL_HEADER_OFFSET = 18
+
+# The "local file header" structure, magic number, size, and indices
+# (section V.A in the format document)
+structFileHeader = "<4s2B4HL2L2H"
+stringFileHeader = "PK\003\004"
+sizeFileHeader = struct.calcsize(structFileHeader)
+
+_FH_SIGNATURE = 0
+_FH_EXTRACT_VERSION = 1
+_FH_EXTRACT_SYSTEM = 2
+_FH_GENERAL_PURPOSE_FLAG_BITS = 3
+_FH_COMPRESSION_METHOD = 4
+_FH_LAST_MOD_TIME = 5
+_FH_LAST_MOD_DATE = 6
+_FH_CRC = 7
+_FH_COMPRESSED_SIZE = 8
+_FH_UNCOMPRESSED_SIZE = 9
+_FH_FILENAME_LENGTH = 10
+_FH_EXTRA_FIELD_LENGTH = 11
+
+# The "Zip64 end of central directory locator" structure, magic number, and size
+structEndArchive64Locator = "<4sLQL"
+stringEndArchive64Locator = "PK\x06\x07"
+sizeEndCentDir64Locator = struct.calcsize(structEndArchive64Locator)
+
+# The "Zip64 end of central directory" record, magic number, size, and indices
+# (section V.G in the format document)
+structEndArchive64 = "<4sQ2H2L4Q"
+stringEndArchive64 = "PK\x06\x06"
+sizeEndCentDir64 = struct.calcsize(structEndArchive64)
+
+_CD64_SIGNATURE = 0
+_CD64_DIRECTORY_RECSIZE = 1
+_CD64_CREATE_VERSION = 2
+_CD64_EXTRACT_VERSION = 3
+_CD64_DISK_NUMBER = 4
+_CD64_DISK_NUMBER_START = 5
+_CD64_NUMBER_ENTRIES_THIS_DISK = 6
+_CD64_NUMBER_ENTRIES_TOTAL = 7
+_CD64_DIRECTORY_SIZE = 8
+_CD64_OFFSET_START_CENTDIR = 9
+
+def is_zipfile(filename):
+    """Quickly see if file is a ZIP file by checking the magic number."""
+    try:
+        fpin = open(filename, "rb")
+        endrec = _EndRecData(fpin)
+        fpin.close()
+        if endrec:
+            return True                 # file has correct magic number
+    except IOError:
+        pass
+    return False
+
+def _EndRecData64(fpin, offset, endrec):
+    """
+    Read the ZIP64 end-of-archive records and use that to update endrec
+    """
+    fpin.seek(offset - sizeEndCentDir64Locator, 2)
+    data = fpin.read(sizeEndCentDir64Locator)
+    sig, diskno, reloff, disks = struct.unpack(structEndArchive64Locator, data)
+    if sig != stringEndArchive64Locator:
+        return endrec
+
+    if diskno != 0 or disks != 1:
+        raise BadZipfile("zipfiles that span multiple disks are not supported")
+
+    # Assume no 'zip64 extensible data'
+    fpin.seek(offset - sizeEndCentDir64Locator - sizeEndCentDir64, 2)
+    data = fpin.read(sizeEndCentDir64)
+    sig, sz, create_version, read_version, disk_num, disk_dir, \
+            dircount, dircount2, dirsize, diroffset = \
+            struct.unpack(structEndArchive64, data)
+    if sig != stringEndArchive64:
+        return endrec
+
+    # Update the original endrec using data from the ZIP64 record
+    endrec[_ECD_SIGNATURE] = sig
+    endrec[_ECD_DISK_NUMBER] = disk_num
+    endrec[_ECD_DISK_START] = disk_dir
+    endrec[_ECD_ENTRIES_THIS_DISK] = dircount
+    endrec[_ECD_ENTRIES_TOTAL] = dircount2
+    endrec[_ECD_SIZE] = dirsize
+    endrec[_ECD_OFFSET] = diroffset
+    return endrec
+
+
+def _EndRecData(fpin):
+    """Return data from the "End of Central Directory" record, or None.
+
+    The data is a list of the nine items in the ZIP "End of central dir"
+    record followed by a tenth item, the file seek offset of this record."""
+
+    # Determine file size
+    fpin.seek(0, 2)
+    filesize = fpin.tell()
+
+    # Check to see if this is ZIP file with no archive comment (the
+    # "end of central directory" structure should be the last item in the
+    # file if this is the case).
+    fpin.seek(-sizeEndCentDir, 2)
+    data = fpin.read()
+    if data[0:4] == stringEndArchive and data[-2:] == "\000\000":
+        # the signature is correct and there's no comment, unpack structure
+        endrec = struct.unpack(structEndArchive, data)
+        endrec=list(endrec)
+
+        # Append a blank comment and record start offset
+        endrec.append("")
+        endrec.append(filesize - sizeEndCentDir)
+
+        # Try to read the "Zip64 end of central directory" structure
+        return _EndRecData64(fpin, -sizeEndCentDir, endrec)
+
+    # Either this is not a ZIP file, or it is a ZIP file with an archive
+    # comment.  Search the end of the file for the "end of central directory"
+    # record signature. The comment is the last item in the ZIP file and may be
+    # up to 64K long.  It is assumed that the "end of central directory" magic
+    # number does not appear in the comment.
+    maxCommentStart = max(filesize - (1 << 16) - sizeEndCentDir, 0)
+    fpin.seek(maxCommentStart, 0)
+    data = fpin.read()
+    start = data.rfind(stringEndArchive)
+    if start >= 0:
+        # found the magic number; attempt to unpack and interpret
+        recData = data[start:start+sizeEndCentDir]
+        endrec = list(struct.unpack(structEndArchive, recData))
+        comment = data[start+sizeEndCentDir:]
+        # check that comment length is correct
+        if endrec[_ECD_COMMENT_SIZE] == len(comment):
+            # Append the archive comment and start offset
+            endrec.append(comment)
+            endrec.append(maxCommentStart + start)
+
+            # Try to read the "Zip64 end of central directory" structure
+            return _EndRecData64(fpin, maxCommentStart + start - filesize,
+                                 endrec)
+
+    # Unable to find a valid end of central directory structure
+    return
+
+
+class ZipInfo (object):
+    """Class with attributes describing each file in the ZIP archive."""
+
+    __slots__ = (
+            'orig_filename',
+            'filename',
+            'date_time',
+            'compress_type',
+            'comment',
+            'extra',
+            'create_system',
+            'create_version',
+            'extract_version',
+            'reserved',
+            'flag_bits',
+            'volume',
+            'internal_attr',
+            'external_attr',
+            'header_offset',
+            'CRC',
+            'compress_size',
+            'file_size',
+            '_raw_time',
+        )
+
+    def __init__(self, filename="NoName", date_time=(1980,1,1,0,0,0)):
+        self.orig_filename = filename   # Original file name in archive
+
+        # Terminate the file name at the first null byte.  Null bytes in file
+        # names are used as tricks by viruses in archives.
+        null_byte = filename.find(chr(0))
+        if null_byte >= 0:
+            filename = filename[0:null_byte]
+        # This is used to ensure paths in generated ZIP files always use
+        # forward slashes as the directory separator, as required by the
+        # ZIP format specification.
+        if os.sep != "/" and os.sep in filename:
+            filename = filename.replace(os.sep, "/")
+
+        self.filename = filename        # Normalized file name
+        self.date_time = date_time      # year, month, day, hour, min, sec
+        # Standard values:
+        self.compress_type = ZIP_STORED # Type of compression for the file
+        self.comment = ""               # Comment for each file
+        self.extra = ""                 # ZIP extra data
+        if sys.platform == 'win32':
+            self.create_system = 0          # System which created ZIP archive
+        else:
+            # Assume everything else is unix-y
+            self.create_system = 3          # System which created ZIP archive
+        self.create_version = 20        # Version which created ZIP archive
+        self.extract_version = 20       # Version needed to extract archive
+        self.reserved = 0               # Must be zero
+        self.flag_bits = 0              # ZIP flag bits
+        self.volume = 0                 # Volume number of file header
+        self.internal_attr = 0          # Internal attributes
+        self.external_attr = 0          # External file attributes
+        # Other attributes are set by class ZipFile:
+        # header_offset         Byte offset to the file header
+        # CRC                   CRC-32 of the uncompressed file
+        # compress_size         Size of the compressed file
+        # file_size             Size of the uncompressed file
+
+    def FileHeader(self):
+        """Return the per-file header as a string."""
+        dt = self.date_time
+        dosdate = (dt[0] - 1980) << 9 | dt[1] << 5 | dt[2]
+        dostime = dt[3] << 11 | dt[4] << 5 | (dt[5] // 2)
+        if self.flag_bits & 0x08:
+            # Set these to zero because we write them after the file data
+            CRC = compress_size = file_size = 0
+        else:
+            CRC = self.CRC
+            compress_size = self.compress_size
+            file_size = self.file_size
+
+        extra = self.extra
+
+        if file_size > ZIP64_LIMIT or compress_size > ZIP64_LIMIT:
+            # File is larger than what fits into a 4 byte integer,
+            # fall back to the ZIP64 extension
+            fmt = '<HHQQ'
+            extra = extra + struct.pack(fmt,
+                    1, struct.calcsize(fmt)-4, file_size, compress_size)
+            file_size = 0xffffffff
+            compress_size = 0xffffffff
+            self.extract_version = max(45, self.extract_version)
+            self.create_version = max(45, self.extract_version)
+
+        filename, flag_bits = self._encodeFilenameFlags()
+        header = struct.pack(structFileHeader, stringFileHeader,
+                 self.extract_version, self.reserved, flag_bits,
+                 self.compress_type, dostime, dosdate, CRC,
+                 compress_size, file_size,
+                 len(filename), len(extra))
+        return header + filename + extra
+
+    def _encodeFilenameFlags(self):
+        if isinstance(self.filename, unicode):
+            try:
+                return self.filename.encode('ascii'), self.flag_bits
+            except UnicodeEncodeError:
+                return self.filename.encode('utf-8'), self.flag_bits | 0x800
+        else:
+            return self.filename, self.flag_bits
+
+    def _decodeFilename(self):
+        if self.flag_bits & 0x800:
+            return self.filename.decode('utf-8')
+        else:
+            return self.filename
+
+    def _decodeExtra(self):
+        # Try to decode the extra field.
+        extra = self.extra
+        unpack = struct.unpack
+        while extra:
+            tp, ln = unpack('<HH', extra[:4])
+            if tp == 1:
+                if ln >= 24:
+                    counts = unpack('<QQQ', extra[4:28])
+                elif ln == 16:
+                    counts = unpack('<QQ', extra[4:20])
+                elif ln == 8:
+                    counts = unpack('<Q', extra[4:12])
+                elif ln == 0:
+                    counts = ()
+                else:
+                    raise RuntimeError, "Corrupt extra field %s"%(ln,)
+
+                idx = 0
+
+                # ZIP64 extension (large files and/or large archives)
+                if self.file_size in (0xffffffffffffffffL, 0xffffffffL):
+                    self.file_size = counts[idx]
+                    idx += 1
+
+                if self.compress_size == 0xFFFFFFFFL:
+                    self.compress_size = counts[idx]
+                    idx += 1
+
+                if self.header_offset == 0xffffffffL:
+                    old = self.header_offset
+                    self.header_offset = counts[idx]
+                    idx+=1
+
+            extra = extra[ln+4:]
+
+
+class _ZipDecrypter:
+    """Class to handle decryption of files stored within a ZIP archive.
+
+    ZIP supports a password-based form of encryption. Even though known
+    plaintext attacks have been found against it, it is still useful
+    to be able to get data out of such a file.
+
+    Usage:
+        zd = _ZipDecrypter(mypwd)
+        plain_char = zd(cypher_char)
+        plain_text = map(zd, cypher_text)
+    """
+
+    def _GenerateCRCTable():
+        """Generate a CRC-32 table.
+
+        ZIP encryption uses the CRC32 one-byte primitive for scrambling some
+        internal keys. We noticed that a direct implementation is faster than
+        relying on binascii.crc32().
+        """
+        poly = 0xedb88320
+        table = [0] * 256
+        for i in range(256):
+            crc = i
+            for j in range(8):
+                if crc & 1:
+                    crc = ((crc >> 1) & 0x7FFFFFFF) ^ poly
+                else:
+                    crc = ((crc >> 1) & 0x7FFFFFFF)
+            table[i] = crc
+        return table
+    crctable = _GenerateCRCTable()
+
+    def _crc32(self, ch, crc):
+        """Compute the CRC32 primitive on one byte."""
+        return ((crc >> 8) & 0xffffff) ^ self.crctable[(crc ^ ord(ch)) & 0xff]
+
+    def __init__(self, pwd):
+        self.key0 = 305419896
+        self.key1 = 591751049
+        self.key2 = 878082192
+        for p in pwd:
+            self._UpdateKeys(p)
+
+    def _UpdateKeys(self, c):
+        self.key0 = self._crc32(c, self.key0)
+        self.key1 = (self.key1 + (self.key0 & 255)) & 4294967295
+        self.key1 = (self.key1 * 134775813 + 1) & 4294967295
+        self.key2 = self._crc32(chr((self.key1 >> 24) & 255), self.key2)
+
+    def __call__(self, c):
+        """Decrypt a single character."""
+        c = ord(c)
+        k = self.key2 | 2
+        c = c ^ (((k * (k^1)) >> 8) & 255)
+        c = chr(c)
+        self._UpdateKeys(c)
+        return c
+
+class ZipExtFile:
+    """File-like object for reading an archive member.
+       Is returned by ZipFile.open().
+    """
+
+    def __init__(self, fileobj, zipinfo, decrypt=None):
+        self.fileobj = fileobj
+        self.decrypter = decrypt
+        self.bytes_read = 0L
+        self.rawbuffer = ''
+        self.readbuffer = ''
+        self.linebuffer = ''
+        self.eof = False
+        self.univ_newlines = False
+        self.nlSeps = ("\n", )
+        self.lastdiscard = ''
+
+        self.compress_type = zipinfo.compress_type
+        self.compress_size = zipinfo.compress_size
+
+        self.closed  = False
+        self.mode    = "r"
+        self.name = zipinfo.filename
+
+        # read from compressed files in 64k blocks
+        self.compreadsize = 64*1024
+        if self.compress_type == ZIP_DEFLATED:
+            self.dc = zlib.decompressobj(-15)
+
+    def set_univ_newlines(self, univ_newlines):
+        self.univ_newlines = univ_newlines
+
+        # pick line separator char(s) based on universal newlines flag
+        self.nlSeps = ("\n", )
+        if self.univ_newlines:
+            self.nlSeps = ("\r\n", "\r", "\n")
+
+    def __iter__(self):
+        return self
+
+    def next(self):
+        nextline = self.readline()
+        if not nextline:
+            raise StopIteration()
+
+        return nextline
+
+    def close(self):
+        self.closed = True
+
+    def _checkfornewline(self):
+        nl, nllen = -1, -1
+        if self.linebuffer:
+            # ugly check for cases where half of an \r\n pair was
+            # read on the last pass, and the \r was discarded.  In this
+            # case we just throw away the \n at the start of the buffer.
+            if (self.lastdiscard, self.linebuffer[0]) == ('\r','\n'):
+                self.linebuffer = self.linebuffer[1:]
+
+            for sep in self.nlSeps:
+                nl = self.linebuffer.find(sep)
+                if nl >= 0:
+                    nllen = len(sep)
+                    return nl, nllen
+
+        return nl, nllen
+
+    def readline(self, size = -1):
+        """Read a line with approx. size. If size is negative,
+           read a whole line.
+        """
+        if size < 0:
+            size = sys.maxint
+        elif size == 0:
+            return ''
+
+        # check for a newline already in buffer
+        nl, nllen = self._checkfornewline()
+
+        if nl >= 0:
+            # the next line was already in the buffer
+            nl = min(nl, size)
+        else:
+            # no line break in buffer - try to read more
+            size -= len(self.linebuffer)
+            while nl < 0 and size > 0:
+                buf = self.read(min(size, 100))
+                if not buf:
+                    break
+                self.linebuffer += buf
+                size -= len(buf)
+
+                # check for a newline in buffer
+                nl, nllen = self._checkfornewline()
+
+            # we either ran out of bytes in the file, or
+            # met the specified size limit without finding a newline,
+            # so return current buffer
+            if nl < 0:
+                s = self.linebuffer
+                self.linebuffer = ''
+                return s
+
+        buf = self.linebuffer[:nl]
+        self.lastdiscard = self.linebuffer[nl:nl + nllen]
+        self.linebuffer = self.linebuffer[nl + nllen:]
+
+        # line is always returned with \n as newline char (except possibly
+        # for a final incomplete line in the file, which is handled above).
+        return buf + "\n"
+
+    def readlines(self, sizehint = -1):
+        """Return a list with all (following) lines. The sizehint parameter
+        is ignored in this implementation.
+        """
+        result = []
+        while True:
+            line = self.readline()
+            if not line: break
+            result.append(line)
+        return result
+
+    def read(self, size = None):
+        # act like file() obj and return empty string if size is 0
+        if size == 0:
+            return ''
+
+        # determine read size
+        bytesToRead = self.compress_size - self.bytes_read
+
+        # adjust read size for encrypted files since the first 12 bytes
+        # are for the encryption/password information
+        if self.decrypter is not None:
+            bytesToRead -= 12
+
+        if size is not None and size >= 0:
+            if self.compress_type == ZIP_STORED:
+                lr = len(self.readbuffer)
+                bytesToRead = min(bytesToRead, size - lr)
+            elif self.compress_type == ZIP_DEFLATED:
+                if len(self.readbuffer) > size:
+                    # the user has requested fewer bytes than we've already
+                    # pulled through the decompressor; don't read any more
+                    bytesToRead = 0
+                else:
+                    # user will use up the buffer, so read some more
+                    lr = len(self.rawbuffer)
+                    bytesToRead = min(bytesToRead, self.compreadsize - lr)
+
+        # avoid reading past end of file contents
+        if bytesToRead + self.bytes_read > self.compress_size:
+            bytesToRead = self.compress_size - self.bytes_read
+
+        # try to read from file (if necessary)
+        if bytesToRead > 0:
+            bytes = self.fileobj.read(bytesToRead)
+            self.bytes_read += len(bytes)
+            self.rawbuffer += bytes
+
+            # handle contents of raw buffer
+            if self.rawbuffer:
+                newdata = self.rawbuffer
+                self.rawbuffer = ''
+
+                # decrypt new data if we were given an object to handle that
+                if newdata and self.decrypter is not None:
+                    newdata = ''.join(map(self.decrypter, newdata))
+
+                # decompress newly read data if necessary
+                if newdata and self.compress_type == ZIP_DEFLATED:
+                    newdata = self.dc.decompress(newdata)
+                    self.rawbuffer = self.dc.unconsumed_tail
+                    if self.eof and len(self.rawbuffer) == 0:
+                        # we're out of raw bytes (both from the file and
+                        # the local buffer); flush just to make sure the
+                        # decompressor is done
+                        newdata += self.dc.flush()
+                        # prevent decompressor from being used again
+                        self.dc = None
+
+                self.readbuffer += newdata
+
+
+        # return what the user asked for
+        if size is None or len(self.readbuffer) <= size:
+            bytes = self.readbuffer
+            self.readbuffer = ''
+        else:
+            bytes = self.readbuffer[:size]
+            self.readbuffer = self.readbuffer[size:]
+
+        return bytes
+
+
+class ZipFile:
+    """ Class with methods to open, read, write, close, list zip files.
+
+    z = ZipFile(file, mode="r", compression=ZIP_STORED, allowZip64=False)
+
+    file: Either the path to the file, or a file-like object.
+          If it is a path, the file will be opened and closed by ZipFile.
+    mode: The mode can be either read "r", write "w" or append "a".
+    compression: ZIP_STORED (no compression) or ZIP_DEFLATED (requires zlib).
+    allowZip64: if True ZipFile will create files with ZIP64 extensions when
+                needed, otherwise it will raise an exception when this would
+                be necessary.
+
+    """
+
+    fp = None                   # Set here since __del__ checks it
+
+    def __init__(self, file, mode="r", compression=ZIP_STORED, allowZip64=False):
+        """Open the ZIP file with mode read "r", write "w" or append "a"."""
+        if mode not in ("r", "w", "a"):
+            raise RuntimeError('ZipFile() requires mode "r", "w", or "a"')
+
+        if compression == ZIP_STORED:
+            pass
+        elif compression == ZIP_DEFLATED:
+            if not zlib:
+                raise RuntimeError,\
+                      "Compression requires the (missing) zlib module"
+        else:
+            raise RuntimeError, "That compression method is not supported"
+
+        self._allowZip64 = allowZip64
+        self._didModify = False
+        self.debug = 0  # Level of printing: 0 through 3
+        self.NameToInfo = {}    # Find file info given name
+        self.filelist = []      # List of ZipInfo instances for archive
+        self.compression = compression  # Method of compression
+        self.mode = key = mode.replace('b', '')[0]
+        self.pwd = None
+        self.comment = ''
+
+        # Check if we were passed a file-like object
+        if isinstance(file, basestring):
+            self._filePassed = 0
+            self.filename = file
+            modeDict = {'r' : 'rb', 'w': 'wb', 'a' : 'r+b'}
+            try:
+                self.fp = open(file, modeDict[mode])
+            except IOError:
+                if mode == 'a':
+                    mode = key = 'w'
+                    self.fp = open(file, modeDict[mode])
+                else:
+                    raise
+        else:
+            self._filePassed = 1
+            self.fp = file
+            self.filename = getattr(file, 'name', None)
+
+        if key == 'r':
+            self._GetContents()
+        elif key == 'w':
+            pass
+        elif key == 'a':
+            try:                        # See if file is a zip file
+                self._RealGetContents()
+                # seek to start of directory and overwrite
+                self.fp.seek(self.start_dir, 0)
+            except BadZipfile:          # file is not a zip file, just append
+                self.fp.seek(0, 2)
+        else:
+            if not self._filePassed:
+                self.fp.close()
+                self.fp = None
+            raise RuntimeError, 'Mode must be "r", "w" or "a"'
+
+    def _GetContents(self):
+        """Read the directory, making sure we close the file if the format
+        is bad."""
+        try:
+            self._RealGetContents()
+        except BadZipfile:
+            if not self._filePassed:
+                self.fp.close()
+                self.fp = None
+            raise
+
+    def _RealGetContents(self):
+        """Read in the table of contents for the ZIP file."""
+        fp = self.fp
+        endrec = _EndRecData(fp)
+        if not endrec:
+            raise BadZipfile, "File is not a zip file"
+        if self.debug > 1:
+            print endrec
+        size_cd = endrec[_ECD_SIZE]             # bytes in central directory
+        offset_cd = endrec[_ECD_OFFSET]         # offset of central directory
+        self.comment = endrec[_ECD_COMMENT]     # archive comment
+
+        # "concat" is zero, unless zip was concatenated to another file
+        concat = endrec[_ECD_LOCATION] - size_cd - offset_cd
+        if endrec[_ECD_SIGNATURE] == stringEndArchive64:
+            # If Zip64 extension structures are present, account for them
+            concat -= (sizeEndCentDir64 + sizeEndCentDir64Locator)
+
+        if self.debug > 2:
+            inferred = concat + offset_cd
+            print "given, inferred, offset", offset_cd, inferred, concat
+        # self.start_dir:  Position of start of central directory
+        self.start_dir = offset_cd + concat
+        fp.seek(self.start_dir, 0)
+        data = fp.read(size_cd)
+        fp = cStringIO.StringIO(data)
+        total = 0
+        while total < size_cd:
+            centdir = fp.read(sizeCentralDir)
+            if centdir[0:4] != stringCentralDir:
+                raise BadZipfile, "Bad magic number for central directory"
+            centdir = struct.unpack(structCentralDir, centdir)
+            if self.debug > 2:
+                print centdir
+            filename = fp.read(centdir[_CD_FILENAME_LENGTH])
+            # Create ZipInfo instance to store file information
+            x = ZipInfo(filename)
+            x.extra = fp.read(centdir[_CD_EXTRA_FIELD_LENGTH])
+            x.comment = fp.read(centdir[_CD_COMMENT_LENGTH])
+            x.header_offset = centdir[_CD_LOCAL_HEADER_OFFSET]
+            (x.create_version, x.create_system, x.extract_version, x.reserved,
+                x.flag_bits, x.compress_type, t, d,
+                x.CRC, x.compress_size, x.file_size) = centdir[1:12]
+            x.volume, x.internal_attr, x.external_attr = centdir[15:18]
+            # Convert date/time code to (year, month, day, hour, min, sec)
+            x._raw_time = t
+            x.date_time = ( (d>>9)+1980, (d>>5)&0xF, d&0x1F,
+                                     t>>11, (t>>5)&0x3F, (t&0x1F) * 2 )
+
+            x._decodeExtra()
+            x.header_offset = x.header_offset + concat
+            x.filename = x._decodeFilename()
+            self.filelist.append(x)
+            self.NameToInfo[x.filename] = x
+
+            # update total bytes read from central directory
+            total = (total + sizeCentralDir + centdir[_CD_FILENAME_LENGTH]
+                     + centdir[_CD_EXTRA_FIELD_LENGTH]
+                     + centdir[_CD_COMMENT_LENGTH])
+
+            if self.debug > 2:
+                print "total", total
+
+
+    def namelist(self):
+        """Return a list of file names in the archive."""
+        l = []
+        for data in self.filelist:
+            l.append(data.filename)
+        return l
+
+    def infolist(self):
+        """Return a list of class ZipInfo instances for files in the
+        archive."""
+        return self.filelist
+
+    def printdir(self):
+        """Print a table of contents for the zip file."""
+        print "%-46s %19s %12s" % ("File Name", "Modified    ", "Size")
+        for zinfo in self.filelist:
+            date = "%d-%02d-%02d %02d:%02d:%02d" % zinfo.date_time[:6]
+            print "%-46s %s %12d" % (zinfo.filename, date, zinfo.file_size)
+
+    def testzip(self):
+        """Read all the files and check the CRC."""
+        chunk_size = 2 ** 20
+        for zinfo in self.filelist:
+            try:
+                # Read by chunks, to avoid an OverflowError or a
+                # MemoryError with very large embedded files.
+                f = self.open(zinfo.filename, "r")
+                while f.read(chunk_size):     # Check CRC-32
+                    pass
+            except BadZipfile:
+                return zinfo.filename
+
+    def getinfo(self, name):
+        """Return the instance of ZipInfo given 'name'."""
+        info = self.NameToInfo.get(name)
+        if info is None:
+            raise KeyError(
+                'There is no item named %r in the archive' % name)
+
+        return info
+
+    def setpassword(self, pwd):
+        """Set default password for encrypted files."""
+        self.pwd = pwd
+
+    def read(self, name, pwd=None):
+        """Return file bytes (as a string) for name."""
+        return self.open(name, "r", pwd).read()
+
+    def open(self, name, mode="r", pwd=None):
+        """Return file-like object for 'name'."""
+        if mode not in ("r", "U", "rU"):
+            raise RuntimeError, 'open() requires mode "r", "U", or "rU"'
+        if not self.fp:
+            raise RuntimeError, \
+                  "Attempt to read ZIP archive that was already closed"
+
+        # Only open a new file for instances where we were not
+        # given a file object in the constructor
+        if self._filePassed:
+            zef_file = self.fp
+        else:
+            zef_file = open(self.filename, 'rb')
+
+        # Make sure we have an info object
+        if isinstance(name, ZipInfo):
+            # 'name' is already an info object
+            zinfo = name
+        else:
+            # Get info object for name
+            zinfo = self.getinfo(name)
+
+        zef_file.seek(zinfo.header_offset, 0)
+
+        # Skip the file header:
+        fheader = zef_file.read(sizeFileHeader)
+        if fheader[0:4] != stringFileHeader:
+            raise BadZipfile, "Bad magic number for file header"
+
+        fheader = struct.unpack(structFileHeader, fheader)
+        fname = zef_file.read(fheader[_FH_FILENAME_LENGTH])
+        if fheader[_FH_EXTRA_FIELD_LENGTH]:
+            zef_file.read(fheader[_FH_EXTRA_FIELD_LENGTH])
+
+        if fname != zinfo.orig_filename:
+            raise BadZipfile, \
+                      'File name in directory "%s" and header "%s" differ.' % (
+                          zinfo.orig_filename, fname)
+
+        # check for encrypted flag & handle password
+        is_encrypted = zinfo.flag_bits & 0x1
+        zd = None
+        if is_encrypted:
+            if not pwd:
+                pwd = self.pwd
+            if not pwd:
+                raise RuntimeError, "File %s is encrypted, " \
+                      "password required for extraction" % name
+
+            zd = _ZipDecrypter(pwd)
+            # The first 12 bytes in the cypher stream is an encryption header
+            #  used to strengthen the algorithm. The first 11 bytes are
+            #  completely random, while the 12th contains the MSB of the CRC,
+            #  or the MSB of the file time depending on the header type
+            #  and is used to check the correctness of the password.
+            bytes = zef_file.read(12)
+            h = map(zd, bytes[0:12])
+            if zinfo.flag_bits & 0x8:
+                # compare against the file type from extended local headers
+                check_byte = (zinfo._raw_time >> 8) & 0xff
+            else:
+                # compare against the CRC otherwise
+                check_byte = (zinfo.CRC >> 24) & 0xff
+            if ord(h[11]) != check_byte:
+                raise RuntimeError("Bad password for file", name)
+
+        # build and return a ZipExtFile
+        if zd is None:
+            zef = ZipExtFile(zef_file, zinfo)
+        else:
+            zef = ZipExtFile(zef_file, zinfo, zd)
+
+        # set universal newlines on ZipExtFile if necessary
+        if "U" in mode:
+            zef.set_univ_newlines(True)
+        return zef
+
+    def extract(self, member, path=None, pwd=None):
+        """Extract a member from the archive to the current working directory,
+           using its full name. Its file information is extracted as accurately
+           as possible. `member' may be a filename or a ZipInfo object. You can
+           specify a different directory using `path'.
+        """
+        if not isinstance(member, ZipInfo):
+            member = self.getinfo(member)
+
+        if path is None:
+            path = os.getcwd()
+
+        return self._extract_member(member, path, pwd)
+
+    def extractall(self, path=None, members=None, pwd=None):
+        """Extract all members from the archive to the current working
+           directory. `path' specifies a different directory to extract to.
+           `members' is optional and must be a subset of the list returned
+           by namelist().
+        """
+        if members is None:
+            members = self.namelist()
+
+        for zipinfo in members:
+            self.extract(zipinfo, path, pwd)
+
+    def _extract_member(self, member, targetpath, pwd):
+        """Extract the ZipInfo object 'member' to a physical
+           file on the path targetpath.
+        """
+        # build the destination pathname, replacing
+        # forward slashes to platform specific separators.
+        # Strip trailing path separator, unless it represents the root.
+        if (targetpath[-1:] in (os.path.sep, os.path.altsep)
+            and len(os.path.splitdrive(targetpath)[1]) > 1):
+            targetpath = targetpath[:-1]
+
+        # don't include leading "/" from file name if present
+        if member.filename[0] == '/':
+            targetpath = os.path.join(targetpath, member.filename[1:])
+        else:
+            targetpath = os.path.join(targetpath, member.filename)
+
+        targetpath = os.path.normpath(targetpath)
+
+        # Create all upper directories if necessary.
+        upperdirs = os.path.dirname(targetpath)
+        if upperdirs and not os.path.exists(upperdirs):
+            os.makedirs(upperdirs)
+
+        if member.filename[-1] == '/':
+            if not os.path.isdir(targetpath):
+                os.mkdir(targetpath)
+            return targetpath
+
+        source = self.open(member, pwd=pwd)
+        target = file(targetpath, "wb")
+        shutil.copyfileobj(source, target)
+        source.close()
+        target.close()
+
+        return targetpath
+
+    def _writecheck(self, zinfo):
+        """Check for errors before writing a file to the archive."""
+        if zinfo.filename in self.NameToInfo:
+            if self.debug:      # Warning for duplicate names
+                print "Duplicate name:", zinfo.filename
+        if self.mode not in ("w", "a"):
+            raise RuntimeError, 'write() requires mode "w" or "a"'
+        if not self.fp:
+            raise RuntimeError, \
+                  "Attempt to write ZIP archive that was already closed"
+        if zinfo.compress_type == ZIP_DEFLATED and not zlib:
+            raise RuntimeError, \
+                  "Compression requires the (missing) zlib module"
+        if zinfo.compress_type not in (ZIP_STORED, ZIP_DEFLATED):
+            raise RuntimeError, \
+                  "That compression method is not supported"
+        if zinfo.file_size > ZIP64_LIMIT:
+            if not self._allowZip64:
+                raise LargeZipFile("Filesize would require ZIP64 extensions")
+        if zinfo.header_offset > ZIP64_LIMIT:
+            if not self._allowZip64:
+                raise LargeZipFile("Zipfile size would require ZIP64 extensions")
+
+    def write(self, filename, arcname=None, compress_type=None):
+        """Put the bytes from filename into the archive under the name
+        arcname."""
+        if not self.fp:
+            raise RuntimeError(
+                  "Attempt to write to ZIP archive that was already closed")
+
+        st = os.stat(filename)
+        isdir = stat.S_ISDIR(st.st_mode)
+        mtime = time.localtime(st.st_mtime)
+        date_time = mtime[0:6]
+        # Create ZipInfo instance to store file information
+        if arcname is None:
+            arcname = filename
+        arcname = os.path.normpath(os.path.splitdrive(arcname)[1])
+        while arcname[0] in (os.sep, os.altsep):
+            arcname = arcname[1:]
+        if isdir:
+            arcname += '/'
+        zinfo = ZipInfo(arcname, date_time)
+        zinfo.external_attr = (st[0] & 0xFFFF) << 16L      # Unix attributes
+        if compress_type is None:
+            zinfo.compress_type = self.compression
+        else:
+            zinfo.compress_type = compress_type
+
+        zinfo.file_size = st.st_size
+        zinfo.flag_bits = 0x00
+        zinfo.header_offset = self.fp.tell()    # Start of header bytes
+
+        self._writecheck(zinfo)
+        self._didModify = True
+
+        if isdir:
+            zinfo.file_size = 0
+            zinfo.compress_size = 0
+            zinfo.CRC = 0
+            self.filelist.append(zinfo)
+            self.NameToInfo[zinfo.filename] = zinfo
+            self.fp.write(zinfo.FileHeader())
+            return
+
+        fp = open(filename, "rb")
+        # Must overwrite CRC and sizes with correct data later
+        zinfo.CRC = CRC = 0
+        zinfo.compress_size = compress_size = 0
+        zinfo.file_size = file_size = 0
+        self.fp.write(zinfo.FileHeader())
+        if zinfo.compress_type == ZIP_DEFLATED:
+            cmpr = zlib.compressobj(zlib.Z_DEFAULT_COMPRESSION,
+                 zlib.DEFLATED, -15)
+        else:
+            cmpr = None
+        while 1:
+            buf = fp.read(1024 * 8)
+            if not buf:
+                break
+            file_size = file_size + len(buf)
+            CRC = crc32(buf, CRC) & 0xffffffff
+            if cmpr:
+                buf = cmpr.compress(buf)
+                compress_size = compress_size + len(buf)
+            self.fp.write(buf)
+        fp.close()
+        if cmpr:
+            buf = cmpr.flush()
+            compress_size = compress_size + len(buf)
+            self.fp.write(buf)
+            zinfo.compress_size = compress_size
+        else:
+            zinfo.compress_size = file_size
+        zinfo.CRC = CRC
+        zinfo.file_size = file_size
+        # Seek backwards and write CRC and file sizes
+        position = self.fp.tell()       # Preserve current position in file
+        self.fp.seek(zinfo.header_offset + 14, 0)
+        self.fp.write(struct.pack("<LLL", zinfo.CRC, zinfo.compress_size,
+              zinfo.file_size))
+        self.fp.seek(position, 0)
+        self.filelist.append(zinfo)
+        self.NameToInfo[zinfo.filename] = zinfo
+
+    def writestr(self, zinfo_or_arcname, bytes):
+        """Write a file into the archive.  The contents is the string
+        'bytes'.  'zinfo_or_arcname' is either a ZipInfo instance or
+        the name of the file in the archive."""
+        if not isinstance(zinfo_or_arcname, ZipInfo):
+            zinfo = ZipInfo(filename=zinfo_or_arcname,
+                            date_time=time.localtime(time.time())[:6])
+            zinfo.compress_type = self.compression
+            zinfo.external_attr = 0600 << 16
+        else:
+            zinfo = zinfo_or_arcname
+
+        if not self.fp:
+            raise RuntimeError(
+                  "Attempt to write to ZIP archive that was already closed")
+
+        zinfo.file_size = len(bytes)            # Uncompressed size
+        zinfo.header_offset = self.fp.tell()    # Start of header bytes
+        self._writecheck(zinfo)
+        self._didModify = True
+        zinfo.CRC = crc32(bytes) & 0xffffffff       # CRC-32 checksum
+        if zinfo.compress_type == ZIP_DEFLATED:
+            co = zlib.compressobj(zlib.Z_DEFAULT_COMPRESSION,
+                 zlib.DEFLATED, -15)
+            bytes = co.compress(bytes) + co.flush()
+            zinfo.compress_size = len(bytes)    # Compressed size
+        else:
+            zinfo.compress_size = zinfo.file_size
+        zinfo.header_offset = self.fp.tell()    # Start of header bytes
+        self.fp.write(zinfo.FileHeader())
+        self.fp.write(bytes)
+        self.fp.flush()
+        if zinfo.flag_bits & 0x08:
+            # Write CRC and file sizes after the file data
+            self.fp.write(struct.pack("<LLL", zinfo.CRC, zinfo.compress_size,
+                  zinfo.file_size))
+        self.filelist.append(zinfo)
+        self.NameToInfo[zinfo.filename] = zinfo
+
+    def __del__(self):
+        """Call the "close()" method in case the user forgot."""
+        self.close()
+
+    def close(self):
+        """Close the file, and for mode "w" and "a" write the ending
+        records."""
+        if self.fp is None:
+            return
+
+        if self.mode in ("w", "a") and self._didModify: # write ending records
+            count = 0
+            pos1 = self.fp.tell()
+            for zinfo in self.filelist:         # write central directory
+                count = count + 1
+                dt = zinfo.date_time
+                dosdate = (dt[0] - 1980) << 9 | dt[1] << 5 | dt[2]
+                dostime = dt[3] << 11 | dt[4] << 5 | (dt[5] // 2)
+                extra = []
+                if zinfo.file_size > ZIP64_LIMIT \
+                        or zinfo.compress_size > ZIP64_LIMIT:
+                    extra.append(zinfo.file_size)
+                    extra.append(zinfo.compress_size)
+                    file_size = 0xffffffff
+                    compress_size = 0xffffffff
+                else:
+                    file_size = zinfo.file_size
+                    compress_size = zinfo.compress_size
+
+                if zinfo.header_offset > ZIP64_LIMIT:
+                    extra.append(zinfo.header_offset)
+                    header_offset = 0xffffffffL
+                else:
+                    header_offset = zinfo.header_offset
+
+                extra_data = zinfo.extra
+                if extra:
+                    # Append a ZIP64 field to the extra's
+                    extra_data = struct.pack(
+                            '<HH' + 'Q'*len(extra),
+                            1, 8*len(extra), *extra) + extra_data
+
+                    extract_version = max(45, zinfo.extract_version)
+                    create_version = max(45, zinfo.create_version)
+                else:
+                    extract_version = zinfo.extract_version
+                    create_version = zinfo.create_version
+
+                try:
+                    filename, flag_bits = zinfo._encodeFilenameFlags()
+                    centdir = struct.pack(structCentralDir,
+                     stringCentralDir, create_version,
+                     zinfo.create_system, extract_version, zinfo.reserved,
+                     flag_bits, zinfo.compress_type, dostime, dosdate,
+                     zinfo.CRC, compress_size, file_size,
+                     len(filename), len(extra_data), len(zinfo.comment),
+                     0, zinfo.internal_attr, zinfo.external_attr,
+                     header_offset)
+                except DeprecationWarning:
+                    print >>sys.stderr, (structCentralDir,
+                     stringCentralDir, create_version,
+                     zinfo.create_system, extract_version, zinfo.reserved,
+                     zinfo.flag_bits, zinfo.compress_type, dostime, dosdate,
+                     zinfo.CRC, compress_size, file_size,
+                     len(zinfo.filename), len(extra_data), len(zinfo.comment),
+                     0, zinfo.internal_attr, zinfo.external_attr,
+                     header_offset)
+                    raise
+                self.fp.write(centdir)
+                self.fp.write(filename)
+                self.fp.write(extra_data)
+                self.fp.write(zinfo.comment)
+
+            pos2 = self.fp.tell()
+            # Write end-of-zip-archive record
+            centDirCount = count
+            centDirSize = pos2 - pos1
+            centDirOffset = pos1
+            if (centDirCount >= ZIP_FILECOUNT_LIMIT or
+                centDirOffset > ZIP64_LIMIT or
+                centDirSize > ZIP64_LIMIT):
+                # Need to write the ZIP64 end-of-archive records
+                zip64endrec = struct.pack(
+                        structEndArchive64, stringEndArchive64,
+                        44, 45, 45, 0, 0, centDirCount, centDirCount,
+                        centDirSize, centDirOffset)
+                self.fp.write(zip64endrec)
+
+                zip64locrec = struct.pack(
+                        structEndArchive64Locator,
+                        stringEndArchive64Locator, 0, pos2, 1)
+                self.fp.write(zip64locrec)
+                centDirCount = min(centDirCount, 0xFFFF)
+                centDirSize = min(centDirSize, 0xFFFFFFFF)
+                centDirOffset = min(centDirOffset, 0xFFFFFFFF)
+
+            # check for valid comment length
+            if len(self.comment) >= ZIP_MAX_COMMENT:
+                if self.debug > 0:
+                    msg = 'Archive comment is too long; truncating to %d bytes' \
+                          % ZIP_MAX_COMMENT
+                self.comment = self.comment[:ZIP_MAX_COMMENT]
+
+            endrec = struct.pack(structEndArchive, stringEndArchive,
+                                 0, 0, centDirCount, centDirCount,
+                                 centDirSize, centDirOffset, len(self.comment))
+            self.fp.write(endrec)
+            self.fp.write(self.comment)
+            self.fp.flush()
+
+        if not self._filePassed:
+            self.fp.close()
+        self.fp = None
+
+
+class PyZipFile(ZipFile):
+    """Class to create ZIP archives with Python library files and packages."""
+
+    def writepy(self, pathname, basename = ""):
+        """Add all files from "pathname" to the ZIP archive.
+
+        If pathname is a package directory, search the directory and
+        all package subdirectories recursively for all *.py and enter
+        the modules into the archive.  If pathname is a plain
+        directory, listdir *.py and enter all modules.  Else, pathname
+        must be a Python *.py file and the module will be put into the
+        archive.  Added modules are always module.pyo or module.pyc.
+        This method will compile the module.py into module.pyc if
+        necessary.
+        """
+        dir, name = os.path.split(pathname)
+        if os.path.isdir(pathname):
+            initname = os.path.join(pathname, "__init__.py")
+            if os.path.isfile(initname):
+                # This is a package directory, add it
+                if basename:
+                    basename = "%s/%s" % (basename, name)
+                else:
+                    basename = name
+                if self.debug:
+                    print "Adding package in", pathname, "as", basename
+                fname, arcname = self._get_codename(initname[0:-3], basename)
+                if self.debug:
+                    print "Adding", arcname
+                self.write(fname, arcname)
+                dirlist = os.listdir(pathname)
+                dirlist.remove("__init__.py")
+                # Add all *.py files and package subdirectories
+                for filename in dirlist:
+                    path = os.path.join(pathname, filename)
+                    root, ext = os.path.splitext(filename)
+                    if os.path.isdir(path):
+                        if os.path.isfile(os.path.join(path, "__init__.py")):
+                            # This is a package directory, add it
+                            self.writepy(path, basename)  # Recursive call
+                    elif ext == ".py":
+                        fname, arcname = self._get_codename(path[0:-3],
+                                         basename)
+                        if self.debug:
+                            print "Adding", arcname
+                        self.write(fname, arcname)
+            else:
+                # This is NOT a package directory, add its files at top level
+                if self.debug:
+                    print "Adding files from directory", pathname
+                for filename in os.listdir(pathname):
+                    path = os.path.join(pathname, filename)
+                    root, ext = os.path.splitext(filename)
+                    if ext == ".py":
+                        fname, arcname = self._get_codename(path[0:-3],
+                                         basename)
+                        if self.debug:
+                            print "Adding", arcname
+                        self.write(fname, arcname)
+        else:
+            if pathname[-3:] != ".py":
+                raise RuntimeError, \
+                      'Files added with writepy() must end with ".py"'
+            fname, arcname = self._get_codename(pathname[0:-3], basename)
+            if self.debug:
+                print "Adding file", arcname
+            self.write(fname, arcname)
+
+    def _get_codename(self, pathname, basename):
+        """Return (filename, archivename) for the path.
+
+        Given a module name path, return the correct file path and
+        archive name, compiling if necessary.  For example, given
+        /python/lib/string, return (/python/lib/string.pyc, string).
+        """
+        file_py  = pathname + ".py"
+        file_pyc = pathname + ".pyc"
+        file_pyo = pathname + ".pyo"
+        if os.path.isfile(file_pyo) and \
+                            os.stat(file_pyo).st_mtime >= os.stat(file_py).st_mtime:
+            fname = file_pyo    # Use .pyo file
+        elif not os.path.isfile(file_pyc) or \
+             os.stat(file_pyc).st_mtime < os.stat(file_py).st_mtime:
+            import py_compile
+            if self.debug:
+                print "Compiling", file_py
+            try:
+                py_compile.compile(file_py, file_pyc, None, True)
+            except py_compile.PyCompileError,err:
+                print err.msg
+            fname = file_pyc
+        else:
+            fname = file_pyc
+        archivename = os.path.split(fname)[1]
+        if basename:
+            archivename = "%s/%s" % (basename, archivename)
+        return (fname, archivename)
+
+
+def main(args = None):
+    import textwrap
+    USAGE=textwrap.dedent("""\
+        Usage:
+            zipfile.py -l zipfile.zip        # Show listing of a zipfile
+            zipfile.py -t zipfile.zip        # Test if a zipfile is valid
+            zipfile.py -e zipfile.zip target # Extract zipfile into target dir
+            zipfile.py -c zipfile.zip src ... # Create zipfile from sources
+        """)
+    if args is None:
+        args = sys.argv[1:]
+
+    if not args or args[0] not in ('-l', '-c', '-e', '-t'):
+        print USAGE
+        sys.exit(1)
+
+    if args[0] == '-l':
+        if len(args) != 2:
+            print USAGE
+            sys.exit(1)
+        zf = ZipFile(args[1], 'r')
+        zf.printdir()
+        zf.close()
+
+    elif args[0] == '-t':
+        if len(args) != 2:
+            print USAGE
+            sys.exit(1)
+        zf = ZipFile(args[1], 'r')
+        zf.testzip()
+        print "Done testing"
+
+    elif args[0] == '-e':
+        if len(args) != 3:
+            print USAGE
+            sys.exit(1)
+
+        zf = ZipFile(args[1], 'r')
+        out = args[2]
+        for path in zf.namelist():
+            if path.startswith('./'):
+                tgt = os.path.join(out, path[2:])
+            else:
+                tgt = os.path.join(out, path)
+
+            tgtdir = os.path.dirname(tgt)
+            if not os.path.exists(tgtdir):
+                os.makedirs(tgtdir)
+            fp = open(tgt, 'wb')
+            fp.write(zf.read(path))
+            fp.close()
+        zf.close()
+
+    elif args[0] == '-c':
+        if len(args) < 3:
+            print USAGE
+            sys.exit(1)
+
+        def addToZip(zf, path, zippath):
+            if os.path.isfile(path):
+                zf.write(path, zippath, ZIP_DEFLATED)
+            elif os.path.isdir(path):
+                for nm in os.listdir(path):
+                    addToZip(zf,
+                            os.path.join(path, nm), os.path.join(zippath, nm))
+            # else: ignore
+
+        zf = ZipFile(args[1], 'w', allowZip64=True)
+        for src in args[2:]:
+            addToZip(zf, src, os.path.basename(src))
+
+        zf.close()
+
+if __name__ == "__main__":
+    main()