TransRead: add pbzip2 support

This patch adds support for multi-stream bz2 files (creted with pbzip2).
Unfortunately, the standard python 2.7 'bz2' module does not support it, so we
use the 'bz2file' module from PyPI.

'bz2file' may not be present in the system, in which case we fall-back to the
standard python 2.7 'bz2' module. As a bonus, 'bz2file' is a little bit faster
than 'bz2' even for single-stream archives.

Change-Id: I7b473987a3bda0241f49da5bbdf1a8a2b3841400
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>

diff --git a/bmaptools/TransRead.py b/bmaptools/TransRead.py
index a2730e2bd49455104146e17bcbcde043b90eaa80..950ab7c700e4346bcc807f1ce4ca7cdfef742dd9 100644 (file)
--- a/bmaptools/TransRead.py
+++ b/bmaptools/TransRead.py
@@ -316,9 +316,20 @@ class TransRead(object):
             elif self.name.endswith('.bz2'):
                 import bz2
 
+                # Let's try to use the bz2file module, which is a backport from
+                # python 3.3 available in PyPI. It supports multiple streams
+                # (pbzip2) and handles handles out-of-memory issues nicely.
+                try:
+                    import bz2file
+
+                    f_obj = bz2file.BZ2File(self._f_objs[-1], 'r')
+                except ImportError:
+                    import bz2
+
+                    f_obj = _CompressedFile(self._f_objs[-1],
+                                      bz2.BZ2Decompressor().decompress, 128)
+
                 self.compression_type = 'bzip2'
-                f_obj = _CompressedFile(self._f_objs[-1],
-                                        bz2.BZ2Decompressor().decompress, 128)
                 self._f_objs.append(f_obj)
 
                 if self.name.endswith('.tar.bz2'):