diff options
Diffstat (limited to 'Lib/zipfile.py')
| -rw-r--r-- | Lib/zipfile.py | 80 |
1 files changed, 58 insertions, 22 deletions
diff --git a/Lib/zipfile.py b/Lib/zipfile.py index 8c2950f..55afa08 100644 --- a/Lib/zipfile.py +++ b/Lib/zipfile.py @@ -667,6 +667,26 @@ class _SharedFile: self._file = None self._close(fileobj) +# Provide the tell method for unseekable stream +class _Tellable: + def __init__(self, fp): + self.fp = fp + self.offset = 0 + + def write(self, data): + n = self.fp.write(data) + self.offset += n + return n + + def tell(self): + return self.offset + + def flush(self): + self.fp.flush() + + def close(self): + self.fp.close() + class ZipExtFile(io.BufferedIOBase): """File-like object for reading an archive member. @@ -994,6 +1014,7 @@ class ZipFile: self.filename = getattr(file, 'name', None) self._fileRefCnt = 1 self._lock = threading.RLock() + self._seekable = True try: if mode == 'r': @@ -1002,13 +1023,24 @@ class ZipFile: # set the modified flag so central directory gets written # even if no files are added to the archive self._didModify = True - self.start_dir = self.fp.tell() + try: + self.start_dir = self.fp.tell() + except (AttributeError, OSError): + self.fp = _Tellable(self.fp) + self.start_dir = 0 + self._seekable = False + else: + # Some file-like objects can provide tell() but not seek() + try: + self.fp.seek(self.start_dir) + except (AttributeError, OSError): + self._seekable = False elif mode == '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) + self.fp.seek(self.start_dir) except BadZipFile: # file is not a zip file, just append self.fp.seek(0, 2) @@ -1415,7 +1447,8 @@ class ZipFile: zinfo.file_size = st.st_size zinfo.flag_bits = 0x00 with self._lock: - self.fp.seek(self.start_dir, 0) + if self._seekable: + self.fp.seek(self.start_dir) zinfo.header_offset = self.fp.tell() # Start of header bytes if zinfo.compress_type == ZIP_LZMA: # Compressed data includes an end-of-stream (EOS) marker @@ -1436,6 +1469,8 @@ class ZipFile: return cmpr = _get_compressor(zinfo.compress_type) + if not self._seekable: + zinfo.flag_bits |= 0x08 with open(filename, "rb") as fp: # Must overwrite CRC and sizes with correct data later zinfo.CRC = CRC = 0 @@ -1464,17 +1499,24 @@ class ZipFile: zinfo.compress_size = file_size zinfo.CRC = CRC zinfo.file_size = file_size - if not zip64 and self._allowZip64: - if file_size > ZIP64_LIMIT: - raise RuntimeError('File size has increased during compressing') - if compress_size > ZIP64_LIMIT: - raise RuntimeError('Compressed size larger than uncompressed size') - # Seek backwards and write file header (which will now include - # correct CRC and file sizes) - self.start_dir = self.fp.tell() # Preserve current position in file - self.fp.seek(zinfo.header_offset, 0) - self.fp.write(zinfo.FileHeader(zip64)) - self.fp.seek(self.start_dir, 0) + if zinfo.flag_bits & 0x08: + # Write CRC and file sizes after the file data + fmt = '<LQQ' if zip64 else '<LLL' + self.fp.write(struct.pack(fmt, zinfo.CRC, zinfo.compress_size, + zinfo.file_size)) + self.start_dir = self.fp.tell() + else: + if not zip64 and self._allowZip64: + if file_size > ZIP64_LIMIT: + raise RuntimeError('File size has increased during compressing') + if compress_size > ZIP64_LIMIT: + raise RuntimeError('Compressed size larger than uncompressed size') + # Seek backwards and write file header (which will now include + # correct CRC and file sizes) + self.start_dir = self.fp.tell() # Preserve current position in file + self.fp.seek(zinfo.header_offset) + self.fp.write(zinfo.FileHeader(zip64)) + self.fp.seek(self.start_dir) self.filelist.append(zinfo) self.NameToInfo[zinfo.filename] = zinfo @@ -1504,11 +1546,8 @@ class ZipFile: zinfo.file_size = len(data) # Uncompressed size with self._lock: - try: + if self._seekable: self.fp.seek(self.start_dir) - except (AttributeError, io.UnsupportedOperation): - # Some file-like objects can provide tell() but not seek() - pass zinfo.header_offset = self.fp.tell() # Start of header data if compress_type is not None: zinfo.compress_type = compress_type @@ -1557,11 +1596,8 @@ class ZipFile: try: if self.mode in ("w", "a") and self._didModify: # write ending records with self._lock: - try: + if self._seekable: self.fp.seek(self.start_dir) - except (AttributeError, io.UnsupportedOperation): - # Some file-like objects can provide tell() but not seek() - pass self._write_end_record() finally: fp = self.fp |