Merge "releasetools: Refactor the condition checking for using imgdiff." (bec8be51) · Commits · e / os / android_build

tools/releasetools/blockimgdiff.py

+50 −26

Original line number	Diff line number	Diff line
		@@ -191,7 +191,6 @@ class Transfer(object):
		self.tgt_sha1 = tgt_sha1
		self.src_sha1 = src_sha1
		self.style = style
		self.intact = tgt_ranges.monotonic and src_ranges.monotonic

		# We use OrderedDict rather than dict so that the output is repeatable;
		# otherwise it would depend on the hash values of the Transfer objects.
		@@ -333,6 +332,45 @@ class BlockImageDiff(object):
		def max_stashed_size(self):
		return self._max_stashed_size

		@staticmethod
		def FileTypeSupportedByImgdiff(filename):
		"""Returns whether the file type is supported by imgdiff."""
		return filename.lower().endswith(('.apk', '.jar', '.zip'))

		def CanUseImgdiff(self, name, tgt_ranges, src_ranges):
		"""Checks whether we can apply imgdiff for the given RangeSets.

		For files in ZIP format (e.g., APKs, JARs, etc.) we would like to use
		'imgdiff -z' if possible. Because it usually produces significantly smaller
		patches than bsdiff.

		This is permissible if all of the following conditions hold.
		- The imgdiff hasn't been disabled by the caller (e.g. squashfs);
		- The file type is supported by imgdiff;
		- The source and target blocks are monotonic (i.e. the data is stored with
		blocks in increasing order);
		- We haven't removed any blocks from the source set.

		If all these conditions are satisfied, concatenating all the blocks in the
		RangeSet in order will produce a valid ZIP file (plus possibly extra zeros
		in the last block). imgdiff is fine with extra zeros at the end of the file.

		Args:
		name: The filename to be diff'd.
		tgt_ranges: The target RangeSet.
		src_ranges: The source RangeSet.

		Returns:
		A boolean result.
		"""
		return (
		not self.disable_imgdiff and
		self.FileTypeSupportedByImgdiff(name) and
		tgt_ranges.monotonic and
		src_ranges.monotonic and
		not tgt_ranges.extra.get('trimmed') and
		not src_ranges.extra.get('trimmed'))

		def Compute(self, prefix):
		# When looking for a source file to use as the diff input for a
		# target file, we try:
		@@ -711,28 +749,13 @@ class BlockImageDiff(object):
		# transfer is intact.
		assert not self.disable_imgdiff
		imgdiff = True
		if not xf.intact:
		if (xf.src_ranges.extra.get('trimmed') or
		xf.tgt_ranges.extra.get('trimmed')):
		imgdiff = False
		xf.patch = None
		else:
		# For files in zip format (eg, APKs, JARs, etc.) we would
		# like to use imgdiff -z if possible (because it usually
		# produces significantly smaller patches than bsdiff).
		# This is permissible if:
		#
		# - imgdiff is not disabled, and
		# - the source and target files are monotonic (ie, the
		# data is stored with blocks in increasing order), and
		# - we haven't removed any blocks from the source set.
		#
		# If these conditions are satisfied then appending all the
		# blocks in the set together in order will produce a valid
		# zip file (plus possibly extra zeros in the last block),
		# which is what imgdiff needs to operate. (imgdiff is
		# fine with extra zeros at the end of the file.)
		imgdiff = (not self.disable_imgdiff and xf.intact and
		xf.tgt_name.split(".")[-1].lower()
		in ("apk", "jar", "zip"))
		imgdiff = self.CanUseImgdiff(
		xf.tgt_name, xf.tgt_ranges, xf.src_ranges)
		xf.style = "imgdiff" if imgdiff else "bsdiff"
		diff_queue.append((index, imgdiff, patch_num))
		patch_num += 1
		@@ -977,7 +1000,7 @@ class BlockImageDiff(object):
		out_of_order += 1
		assert xf.src_ranges.overlaps(u.tgt_ranges)
		xf.src_ranges = xf.src_ranges.subtract(u.tgt_ranges)
		xf.intact = False
		xf.src_ranges.extra['trimmed'] = True

		if xf.style == "diff" and not xf.src_ranges:
		# nothing left to diff from; treat as new data
		@@ -1261,11 +1284,12 @@ class BlockImageDiff(object):
		style, by_id)
		return

		if tgt_name.split(".")[-1].lower() in ("apk", "jar", "zip"):
		split_enable = (not self.disable_imgdiff and src_ranges.monotonic and
		tgt_ranges.monotonic)
		if split_enable and (self.tgt.RangeSha1(tgt_ranges) !=
		self.src.RangeSha1(src_ranges)):
		# Split large APKs with imgdiff, if possible. We're intentionally checking
		# file types one more time (CanUseImgdiff() checks that as well), before
		# calling the costly RangeSha1()s.
		if (self.FileTypeSupportedByImgdiff(tgt_name) and
		self.tgt.RangeSha1(tgt_ranges) != self.src.RangeSha1(src_ranges)):
		if self.CanUseImgdiff(tgt_name, tgt_ranges, src_ranges):
		large_apks.append((tgt_name, src_name, tgt_ranges, src_ranges))
		return

tools/releasetools/test_blockimgdiff.py

+51 −0

Original line number	Diff line number	Diff line
		@@ -172,3 +172,54 @@ class BlockImageDiffTest(unittest.TestCase):
		# Insufficient cache to stash 15 blocks (size * 0.8 < 15).
		common.OPTIONS.cache_size = 15 * 4096
		self.assertEqual(15, block_image_diff.ReviseStashSize())

		def test_FileTypeSupportedByImgdiff(self):
		self.assertTrue(
		BlockImageDiff.FileTypeSupportedByImgdiff(
		"/system/priv-app/Settings/Settings.apk"))
		self.assertTrue(
		BlockImageDiff.FileTypeSupportedByImgdiff(
		"/system/framework/am.jar"))
		self.assertTrue(
		BlockImageDiff.FileTypeSupportedByImgdiff(
		"/system/etc/security/otacerts.zip"))

		self.assertFalse(
		BlockImageDiff.FileTypeSupportedByImgdiff(
		"/system/framework/arm/boot.oat"))
		self.assertFalse(
		BlockImageDiff.FileTypeSupportedByImgdiff(
		"/system/priv-app/notanapk"))

		def test_CanUseImgdiff(self):
		block_image_diff = BlockImageDiff(EmptyImage(), EmptyImage())
		self.assertTrue(
		block_image_diff.CanUseImgdiff(
		"/system/app/app1.apk", RangeSet("10-15"), RangeSet("0-5")))

		def test_CanUseImgdiff_ineligible(self):
		# Disabled by caller.
		block_image_diff = BlockImageDiff(EmptyImage(), EmptyImage(),
		disable_imgdiff=True)
		self.assertFalse(
		block_image_diff.CanUseImgdiff(
		"/system/app/app1.apk", RangeSet("10-15"), RangeSet("0-5")))

		# Unsupported file type.
		block_image_diff = BlockImageDiff(EmptyImage(), EmptyImage())
		self.assertFalse(
		block_image_diff.CanUseImgdiff(
		"/system/bin/gzip", RangeSet("10-15"), RangeSet("0-5")))

		# At least one of the ranges is in non-monotonic order.
		self.assertFalse(
		block_image_diff.CanUseImgdiff(
		"/system/app/app2.apk", RangeSet("10-15"),
		RangeSet("15-20 30 10-14")))

		# At least one of the ranges has been modified.
		src_ranges = RangeSet("0-5")
		src_ranges.extra['trimmed'] = True
		self.assertFalse(
		block_image_diff.CanUseImgdiff(
		"/vendor/app/app3.apk", RangeSet("10-15"), src_ranges))