| 128 | self._decompressor = self._decomp_factory(**self._decomp_args) |
| 129 | |
| 130 | def seek(self, offset, whence=io.SEEK_SET): |
| 131 | # Recalculate offset as an absolute file position. |
| 132 | if whence == io.SEEK_SET: |
| 133 | pass |
| 134 | elif whence == io.SEEK_CUR: |
| 135 | offset = self._pos + offset |
| 136 | elif whence == io.SEEK_END: |
| 137 | # Seeking relative to EOF - we need to know the file's size. |
| 138 | if self._size < 0: |
| 139 | while self.read(io.DEFAULT_BUFFER_SIZE): |
| 140 | pass |
| 141 | offset = self._size + offset |
| 142 | else: |
| 143 | raise ValueError("Invalid value for whence: {}".format(whence)) |
| 144 | |
| 145 | # Make it so that offset is the number of bytes to skip forward. |
| 146 | if offset < self._pos: |
| 147 | self._rewind() |
| 148 | else: |
| 149 | offset -= self._pos |
| 150 | |
| 151 | # Read and discard data until we reach the desired position. |
| 152 | while offset > 0: |
| 153 | data = self.read(min(io.DEFAULT_BUFFER_SIZE, offset)) |
| 154 | if not data: |
| 155 | break |
| 156 | offset -= len(data) |
| 157 | |
| 158 | return self._pos |
| 159 | |
| 160 | def tell(self): |
| 161 | """Return the current file position.""" |