Remove the assumption of target chunk size in imgdiff
In the split mode of imgdiff, we used to assume that the size of a split
target chunk is always greater than the blocksize i.e. 4096. This may
lead to the following assertion failure:
I0221 04:57:33.451323 818464 common.py:205 imgdiff F 02-21 04:57:33 821203 821203 imgdiff.cpp:999]
Check failed: tgt_size >= BLOCK_SIZE (tgt_size=476, BLOCK_SIZE=4096)
This CL removes the assumption and handles the edge cases.
Test: generate and verify the incremental update for TFs in the bug; unit test passes
Bug: 73757557
Bug: 73711365
Change-Id: Iadbb4ee658995f5856cd488f3793980881a59620
diff --git a/applypatch/imgdiff.cpp b/applypatch/imgdiff.cpp
index 3dae63d..674cc2b 100644
--- a/applypatch/imgdiff.cpp
+++ b/applypatch/imgdiff.cpp
@@ -955,14 +955,17 @@
tgt->GetRawDataLength());
}
} else {
- ZipModeImage::AddSplitImageFromChunkList(tgt_image, src_image, src_ranges, split_tgt_chunks,
- split_src_chunks, split_tgt_images,
- split_src_images);
+ bool added_image = ZipModeImage::AddSplitImageFromChunkList(
+ tgt_image, src_image, src_ranges, split_tgt_chunks, split_src_chunks, split_tgt_images,
+ split_src_images);
split_tgt_chunks.clear();
split_src_chunks.clear();
- used_src_ranges.Insert(src_ranges);
- split_src_ranges->push_back(std::move(src_ranges));
+ // No need to update the split_src_ranges if we don't update the split source images.
+ if (added_image) {
+ used_src_ranges.Insert(src_ranges);
+ split_src_ranges->push_back(std::move(src_ranges));
+ }
src_ranges.Clear();
// We don't have enough space for the current chunk; start a new split image and handle
@@ -973,9 +976,12 @@
// TODO Trim it in case the CD exceeds limit too much.
src_ranges.Insert(central_directory->GetStartOffset(), central_directory->DataLengthForPatch());
- ZipModeImage::AddSplitImageFromChunkList(tgt_image, src_image, src_ranges, split_tgt_chunks,
- split_src_chunks, split_tgt_images, split_src_images);
- split_src_ranges->push_back(std::move(src_ranges));
+ bool added_image = ZipModeImage::AddSplitImageFromChunkList(tgt_image, src_image, src_ranges,
+ split_tgt_chunks, split_src_chunks,
+ split_tgt_images, split_src_images);
+ if (added_image) {
+ split_src_ranges->push_back(std::move(src_ranges));
+ }
ValidateSplitImages(*split_tgt_images, *split_src_images, *split_src_ranges,
tgt_image.file_content_.size());
@@ -983,7 +989,7 @@
return true;
}
-void ZipModeImage::AddSplitImageFromChunkList(const ZipModeImage& tgt_image,
+bool ZipModeImage::AddSplitImageFromChunkList(const ZipModeImage& tgt_image,
const ZipModeImage& src_image,
const SortedRangeSet& split_src_ranges,
const std::vector<ImageChunk>& split_tgt_chunks,
@@ -991,12 +997,6 @@
std::vector<ZipModeImage>* split_tgt_images,
std::vector<ZipModeImage>* split_src_images) {
CHECK(!split_tgt_chunks.empty());
- // Target chunks should occupy at least one block.
- // TODO put a warning and change the type to raw if it happens in extremely rare cases.
- size_t tgt_size = split_tgt_chunks.back().GetStartOffset() +
- split_tgt_chunks.back().DataLengthForPatch() -
- split_tgt_chunks.front().GetStartOffset();
- CHECK_GE(tgt_size, BLOCK_SIZE);
std::vector<ImageChunk> aligned_tgt_chunks;
@@ -1015,7 +1015,12 @@
i++;
}
- CHECK_LT(i, split_tgt_chunks.size());
+
+ // Nothing left after alignment in the current split tgt chunks; skip adding the split_tgt_image.
+ if (i == split_tgt_chunks.size()) {
+ return false;
+ }
+
aligned_tgt_chunks.insert(aligned_tgt_chunks.end(), split_tgt_chunks.begin() + i + 1,
split_tgt_chunks.end());
CHECK(!aligned_tgt_chunks.empty());
@@ -1024,8 +1029,10 @@
size_t end_offset =
aligned_tgt_chunks.back().GetStartOffset() + aligned_tgt_chunks.back().GetRawDataLength();
if (end_offset % BLOCK_SIZE != 0 && end_offset < tgt_image.file_content_.size()) {
+ size_t tail_block_length = std::min<size_t>(tgt_image.file_content_.size() - end_offset,
+ BLOCK_SIZE - (end_offset % BLOCK_SIZE));
aligned_tgt_chunks.emplace_back(CHUNK_NORMAL, end_offset, &tgt_image.file_content_,
- BLOCK_SIZE - (end_offset % BLOCK_SIZE));
+ tail_block_length);
}
ZipModeImage split_tgt_image(false);
@@ -1049,6 +1056,8 @@
split_tgt_images->push_back(std::move(split_tgt_image));
split_src_images->push_back(std::move(split_src_image));
+
+ return true;
}
void ZipModeImage::ValidateSplitImages(const std::vector<ZipModeImage>& split_tgt_images,
@@ -1536,7 +1545,7 @@
" patches together and output them into <patch-file>.\n"
" --split-info, Output the split information (patch_size, tgt_size, src_ranges);\n"
" zip mode with block-limit only.\n"
- " --debug_dir, Debug directory to put the split srcs and patches, zip mode only.\n"
+ " --debug-dir, Debug directory to put the split srcs and patches, zip mode only.\n"
" -v, --verbose, Enable verbose logging.";
return 2;
}