tree 904b30c4b1f270d7f991105beecec87302eddcea
parent 4c82df357f29cba23393732bcd6f411f856eb2e6
author Alex Deymo <deymo@chromium.org> 1415663918 -0800
committer chrome-internal-fetch <chrome-internal-fetch@google.com> 1415772805 +0000

update_engine: Add support for parsing the size of a squashfs.

This patch extends the utils::GetFilesystemSize() function to support
squashfs (in addition to the existing ext3 support). The filesystem
type is detected automatically.

squashfs doesn't define a block size for the physical device that it
relies on. There's a definition of block size for the data before
compression that doesn't affect the block size used for the underlying
device. When creating the squashfs, it is by default padded to 4 KiB,
so we assume 4 KiB as the block size. This is also the minimum block
size required by verity to compute hashes in all supported archs.

BUG=chromium:430956
TEST=Unittest added.

Change-Id: Ia683a27c094e25952e8d665535dc6219c849bdd0
Reviewed-on: https://chromium-review.googlesource.com/228906
Reviewed-by: Gaurav Shah <gauravsh@chromium.org>
Commit-Queue: Alex Deymo <deymo@chromium.org>
Tested-by: Alex Deymo <deymo@chromium.org>