generate version 2 blockimgdiff files
Generate version 2 of the block_image_update transfer list format.
This improves patch size by a different strategy for dealing with
out-of-order transfers. If transfer A must be done before transfer B
due to B overwriting A's source but we want to do B before A, we
resolve the conflict by:
- before B is executed, we save ("stash") the overlapping region (ie
the blocks B will overwrite that A wants to read)
- when A is executed, it will read those parts of source data from
the stash rather than from the image.
This reverses the ordering constraint; with these additions now B
*must* go before A. The implementation of the stash is left up to the
code that executes the transfer list to apply the patch; it could hold
stashed data in RAM or on a scratch disk such as /cache, if available.
The code retains the ability to build a version 1 block image patch;
it's needed for processing older target-files.
Change-Id: Ia9aa0bd45d5dc3ef7c5835e483b1b2ead10135fe
diff --git a/tools/releasetools/common.py b/tools/releasetools/common.py
index 815c76c..96075a9 100644
--- a/tools/releasetools/common.py
+++ b/tools/releasetools/common.py
@@ -1030,7 +1030,14 @@
self.partition = partition
self.check_first_block = check_first_block
- b = blockimgdiff.BlockImageDiff(tgt, src, threads=OPTIONS.worker_threads)
+ version = 1
+ if OPTIONS.info_dict:
+ version = max(
+ int(i) for i in
+ OPTIONS.info_dict.get("blockimgdiff_versions", "1").split(","))
+
+ b = blockimgdiff.BlockImageDiff(tgt, src, threads=OPTIONS.worker_threads,
+ version=version)
tmpdir = tempfile.mkdtemp()
OPTIONS.tempfiles.append(tmpdir)
self.path = os.path.join(tmpdir, partition)