diff options
Diffstat (limited to 'applypatch/imgdiff.cpp')
| -rw-r--r-- | applypatch/imgdiff.cpp | 959 |
1 files changed, 567 insertions, 392 deletions
diff --git a/applypatch/imgdiff.cpp b/applypatch/imgdiff.cpp index fc240644f..880265260 100644 --- a/applypatch/imgdiff.cpp +++ b/applypatch/imgdiff.cpp @@ -196,7 +196,8 @@ class ImageChunk { size_t DataLengthForPatch() const; void Dump() const { - printf("type %d start %zu len %zu\n", type_, start_, DataLengthForPatch()); + printf("type: %d, start: %zu, len: %zu, name: %s\n", type_, start_, DataLengthForPatch(), + entry_name_.c_str()); } void SetSourceInfo(const ImageChunk& other); @@ -211,7 +212,7 @@ class ImageChunk { size_t GetHeaderSize(size_t patch_size) const; // Return the offset of the next patch into the patch data. - size_t WriteHeaderToFd(int fd, const std::vector<uint8_t>& patch, size_t offset); + size_t WriteHeaderToFd(int fd, const std::vector<uint8_t>& patch, size_t offset) const; /* * Cause a gzip chunk to be treated as a normal chunk (ie, as a blob @@ -233,6 +234,14 @@ class ImageChunk { bool IsAdjacentNormal(const ImageChunk& other) const; void MergeAdjacentNormal(const ImageChunk& other); + /* + * Compute a bsdiff patch between |this| and the input source chunks. + * Store the result in the patch_data. + * |bsdiff_cache| can be used to cache the suffix array if the same |src| chunk is used + * repeatedly, pass nullptr if not needed. + */ + bool MakePatch(const ImageChunk& src, std::vector<uint8_t>* patch_data, saidx_t** bsdiff_cache); + private: int type_; // CHUNK_NORMAL, CHUNK_DEFLATE, CHUNK_RAW size_t start_; // offset of chunk in the original input file @@ -322,7 +331,7 @@ bool ImageChunk::ChangeChunkToRaw(size_t patch_size) { void ImageChunk::ChangeDeflateChunkToNormal() { if (type_ != CHUNK_DEFLATE) return; type_ = CHUNK_NORMAL; - entry_name_.clear(); + // No need to clear the entry name. uncompressed_data_.clear(); } @@ -345,7 +354,7 @@ size_t ImageChunk::GetHeaderSize(size_t patch_size) const { } } -size_t ImageChunk::WriteHeaderToFd(int fd, const std::vector<uint8_t>& patch, size_t offset) { +size_t ImageChunk::WriteHeaderToFd(int fd, const std::vector<uint8_t>& patch, size_t offset) const { Write4(fd, type_); switch (type_) { case CHUNK_NORMAL: @@ -393,6 +402,68 @@ void ImageChunk::MergeAdjacentNormal(const ImageChunk& other) { raw_data_len_ = raw_data_len_ + other.raw_data_len_; } +bool ImageChunk::MakePatch(const ImageChunk& src, std::vector<uint8_t>* patch_data, + saidx_t** bsdiff_cache) { + if (ChangeChunkToRaw(0)) { + size_t patch_size = DataLengthForPatch(); + patch_data->resize(patch_size); + std::copy(DataForPatch(), DataForPatch() + patch_size, patch_data->begin()); + return true; + } + +#if defined(__ANDROID__) + char ptemp[] = "/data/local/tmp/imgdiff-patch-XXXXXX"; +#else + char ptemp[] = "/tmp/imgdiff-patch-XXXXXX"; +#endif + + int fd = mkstemp(ptemp); + if (fd == -1) { + printf("MakePatch failed to create a temporary file: %s\n", strerror(errno)); + return false; + } + close(fd); + + int r = bsdiff::bsdiff(src.DataForPatch(), src.DataLengthForPatch(), DataForPatch(), + DataLengthForPatch(), ptemp, bsdiff_cache); + if (r != 0) { + printf("bsdiff() failed: %d\n", r); + return false; + } + + android::base::unique_fd patch_fd(open(ptemp, O_RDONLY)); + if (patch_fd == -1) { + printf("failed to open %s: %s\n", ptemp, strerror(errno)); + return false; + } + struct stat st; + if (fstat(patch_fd, &st) != 0) { + printf("failed to stat patch file %s: %s\n", ptemp, strerror(errno)); + return false; + } + + size_t sz = static_cast<size_t>(st.st_size); + // Change the chunk type to raw if the patch takes less space that way. + if (ChangeChunkToRaw(sz)) { + unlink(ptemp); + size_t patch_size = DataLengthForPatch(); + patch_data->resize(patch_size); + std::copy(DataForPatch(), DataForPatch() + patch_size, patch_data->begin()); + return true; + } + patch_data->resize(sz); + if (!android::base::ReadFully(patch_fd, patch_data->data(), sz)) { + printf("failed to read \"%s\" %s\n", ptemp, strerror(errno)); + unlink(ptemp); + return false; + } + + unlink(ptemp); + SetSourceInfo(src); + + return true; +} + bool ImageChunk::ReconstructDeflateChunk() { if (type_ != CHUNK_DEFLATE) { printf("attempt to reconstruct non-deflate chunk\n"); @@ -458,195 +529,467 @@ bool ImageChunk::TryReconstruction(int level) { return true; } -// EOCD record -// offset 0: signature 0x06054b50, 4 bytes -// offset 4: number of this disk, 2 bytes -// ... -// offset 20: comment length, 2 bytes -// offset 22: comment, n bytes -static bool GetZipFileSize(const std::vector<uint8_t>& zip_file, size_t* input_file_size) { - if (zip_file.size() < 22) { - printf("file is too small to be a zip file\n"); - return false; +// Interface for zip_mode and image_mode images. We initialize the image from an input file and +// split the file content into a list of image chunks. +class Image { + public: + explicit Image(bool is_source) : is_source_(is_source) {} + + virtual ~Image() {} + + // Create a list of image chunks from input file. + virtual bool Initialize(const std::string& filename) = 0; + + // Look for runs of adjacent normal chunks and compress them down into a single chunk. (Such + // runs can be produced when deflate chunks are changed to normal chunks.) + void MergeAdjacentNormalChunks(); + + // In zip mode, find the matching deflate source chunk by entry name. Search for normal chunks + // also if |find_normal| is true. + ImageChunk* FindChunkByName(const std::string& name, bool find_normal = false); + + // Write the contents of |patch_data| to |patch_fd|. + bool WritePatchDataToFd(const std::vector<std::vector<uint8_t>>& patch_data, int patch_fd) const; + + void DumpChunks() const; + + // Non const iterators to access the stored ImageChunks. + std::vector<ImageChunk>::iterator begin() { + return chunks_.begin(); } - // Look for End of central directory record of the zip file, and calculate the actual - // zip_file size. - for (int i = zip_file.size() - 22; i >= 0; i--) { - if (zip_file[i] == 0x50) { - if (get_unaligned<uint32_t>(&zip_file[i]) == 0x06054b50) { - // double-check: this archive consists of a single "disk". - CHECK_EQ(get_unaligned<uint16_t>(&zip_file[i + 4]), 0); + std::vector<ImageChunk>::iterator end() { + return chunks_.end(); + } + // Return a pointer to the ith ImageChunk. + ImageChunk* Get(size_t i) { + CHECK_LT(i, chunks_.size()); + return &chunks_[i]; + } - uint16_t comment_length = get_unaligned<uint16_t>(&zip_file[i + 20]); - size_t file_size = i + 22 + comment_length; - CHECK_LE(file_size, zip_file.size()); - *input_file_size = file_size; - return true; + size_t NumOfChunks() const { + return chunks_.size(); + } + + protected: + bool ReadFile(const std::string& filename, std::vector<uint8_t>* file_content); + + bool is_source_; // True if it's for source chunks. + std::vector<ImageChunk> chunks_; // Internal storage of ImageChunk. + std::vector<uint8_t> file_content_; // Store the whole input file in memory. +}; + +void Image::MergeAdjacentNormalChunks() { + size_t merged_last = 0, cur = 0; + while (cur < chunks_.size()) { + // Look for normal chunks adjacent to the current one. If such chunk exists, extend the + // length of the current normal chunk. + size_t to_check = cur + 1; + while (to_check < chunks_.size() && chunks_[cur].IsAdjacentNormal(chunks_[to_check])) { + chunks_[cur].MergeAdjacentNormal(chunks_[to_check]); + to_check++; + } + + if (merged_last != cur) { + chunks_[merged_last] = std::move(chunks_[cur]); + } + merged_last++; + cur = to_check; + } + if (merged_last < chunks_.size()) { + chunks_.erase(chunks_.begin() + merged_last, chunks_.end()); + } +} + +ImageChunk* Image::FindChunkByName(const std::string& name, bool find_normal) { + if (name.empty()) { + return nullptr; + } + for (auto& chunk : chunks_) { + if ((chunk.GetType() == CHUNK_DEFLATE || find_normal) && chunk.GetEntryName() == name) { + return &chunk; + } + } + return nullptr; +} + +bool Image::WritePatchDataToFd(const std::vector<std::vector<uint8_t>>& patch_data, + int patch_fd) const { + // Figure out how big the imgdiff file header is going to be, so that we can correctly compute + // the offset of each bsdiff patch within the file. + CHECK_EQ(chunks_.size(), patch_data.size()); + size_t total_header_size = 12; + for (size_t i = 0; i < chunks_.size(); ++i) { + total_header_size += chunks_[i].GetHeaderSize(patch_data[i].size()); + } + + size_t offset = total_header_size; + + // Write out the headers. + if (!android::base::WriteStringToFd("IMGDIFF2", patch_fd)) { + printf("failed to write \"IMGDIFF2\": %s\n", strerror(errno)); + return false; + } + Write4(patch_fd, static_cast<int32_t>(chunks_.size())); + for (size_t i = 0; i < chunks_.size(); ++i) { + printf("chunk %zu: ", i); + offset = chunks_[i].WriteHeaderToFd(patch_fd, patch_data[i], offset); + } + + // Append each chunk's bsdiff patch, in order. + for (size_t i = 0; i < chunks_.size(); ++i) { + if (chunks_[i].GetType() != CHUNK_RAW) { + if (!android::base::WriteFully(patch_fd, patch_data[i].data(), patch_data[i].size())) { + printf("failed to write %zu bytes patch for chunk %zu\n", patch_data[i].size(), i); + return false; } } } - // EOCD not found, this file is likely not a valid zip file. - return false; + return true; +} + +void Image::DumpChunks() const { + std::string type = is_source_ ? "source" : "target"; + printf("Dumping chunks for %s\n", type.c_str()); + for (size_t i = 0; i < chunks_.size(); ++i) { + printf("chunk %zu: ", i); + chunks_[i].Dump(); + } } -static bool ReadZip(const char* filename, std::vector<ImageChunk>* chunks, - std::vector<uint8_t>* zip_file, bool include_pseudo_chunk) { - CHECK(chunks != nullptr && zip_file != nullptr); +bool Image::ReadFile(const std::string& filename, std::vector<uint8_t>* file_content) { + CHECK(file_content != nullptr); - android::base::unique_fd fd(open(filename, O_RDONLY)); + android::base::unique_fd fd(open(filename.c_str(), O_RDONLY)); if (fd == -1) { - printf("failed to open \"%s\" %s\n", filename, strerror(errno)); + printf("failed to open \"%s\" %s\n", filename.c_str(), strerror(errno)); return false; } struct stat st; if (fstat(fd, &st) != 0) { - printf("failed to stat \"%s\": %s\n", filename, strerror(errno)); + printf("failed to stat \"%s\": %s\n", filename.c_str(), strerror(errno)); return false; } size_t sz = static_cast<size_t>(st.st_size); - zip_file->resize(sz); - if (!android::base::ReadFully(fd, zip_file->data(), sz)) { - printf("failed to read \"%s\" %s\n", filename, strerror(errno)); + file_content->resize(sz); + if (!android::base::ReadFully(fd, file_content->data(), sz)) { + printf("failed to read \"%s\" %s\n", filename.c_str(), strerror(errno)); return false; } fd.reset(); - // Trim the trailing zeros before we pass the file to ziparchive handler. + return true; +} + +class ZipModeImage : public Image { + public: + explicit ZipModeImage(bool is_source) : Image(is_source) {} + + bool Initialize(const std::string& filename) override; + + const ImageChunk& PseudoSource() const { + CHECK(is_source_); + CHECK(pseudo_source_ != nullptr); + return *pseudo_source_; + } + + // Verify that we can reconstruct the deflate chunks; also change the type to CHUNK_NORMAL if + // src and tgt are identical. + static bool CheckAndProcessChunks(ZipModeImage* tgt_image, ZipModeImage* src_image); + + // Compute the patches against the input image, and write the data into |patch_name|. + static bool GeneratePatches(ZipModeImage* tgt_image, ZipModeImage* src_image, + const std::string& patch_name); + + private: + // Initialize image chunks based on the zip entries. + bool InitializeChunks(const std::string& filename, ZipArchiveHandle handle); + // Add the a zip entry to the list. + bool AddZipEntryToChunks(ZipArchiveHandle handle, const std::string& entry_name, ZipEntry* entry); + // Return the real size of the zip file. (omit the trailing zeros that used for alignment) + bool GetZipFileSize(size_t* input_file_size); + + // The pesudo source chunk for bsdiff if there's no match for the given target chunk. It's in + // fact the whole source file. + std::unique_ptr<ImageChunk> pseudo_source_; +}; + +bool ZipModeImage::Initialize(const std::string& filename) { + if (!ReadFile(filename, &file_content_)) { + return false; + } + + // Omit the trailing zeros before we pass the file to ziparchive handler. size_t zipfile_size; - if (!GetZipFileSize(*zip_file, &zipfile_size)) { - printf("failed to parse the actual size of %s\n", filename); + if (!GetZipFileSize(&zipfile_size)) { + printf("failed to parse the actual size of %s\n", filename.c_str()); return false; } ZipArchiveHandle handle; - int err = OpenArchiveFromMemory(zip_file->data(), zipfile_size, filename, &handle); + int err = OpenArchiveFromMemory(const_cast<uint8_t*>(file_content_.data()), zipfile_size, + filename.c_str(), &handle); if (err != 0) { - printf("failed to open zip file %s: %s\n", filename, ErrorCodeString(err)); + printf("failed to open zip file %s: %s\n", filename.c_str(), ErrorCodeString(err)); CloseArchive(handle); return false; } - // Create a list of deflated zip entries, sorted by offset. - std::vector<std::pair<std::string, ZipEntry>> temp_entries; + if (is_source_) { + pseudo_source_ = std::make_unique<ImageChunk>(CHUNK_NORMAL, 0, &file_content_, zipfile_size); + } + if (!InitializeChunks(filename, handle)) { + CloseArchive(handle); + return false; + } + + CloseArchive(handle); + return true; +} + +// Iterate the zip entries and compose the image chunks accordingly. +bool ZipModeImage::InitializeChunks(const std::string& filename, ZipArchiveHandle handle) { void* cookie; int ret = StartIteration(handle, &cookie, nullptr, nullptr); if (ret != 0) { - printf("failed to iterate over entries in %s: %s\n", filename, ErrorCodeString(ret)); - CloseArchive(handle); + printf("failed to iterate over entries in %s: %s\n", filename.c_str(), ErrorCodeString(ret)); return false; } + // Create a list of deflated zip entries, sorted by offset. + std::vector<std::pair<std::string, ZipEntry>> temp_entries; ZipString name; ZipEntry entry; while ((ret = Next(cookie, &entry, &name)) == 0) { if (entry.method == kCompressDeflated) { - std::string entryname(name.name, name.name + name.name_length); - temp_entries.push_back(std::make_pair(entryname, entry)); + std::string entry_name(name.name, name.name + name.name_length); + temp_entries.emplace_back(entry_name, entry); } } if (ret != -1) { printf("Error while iterating over zip entries: %s\n", ErrorCodeString(ret)); - CloseArchive(handle); return false; } std::sort(temp_entries.begin(), temp_entries.end(), - [](auto& entry1, auto& entry2) { - return entry1.second.offset < entry2.second.offset; - }); + [](auto& entry1, auto& entry2) { return entry1.second.offset < entry2.second.offset; }); EndIteration(cookie); - if (include_pseudo_chunk) { - chunks->emplace_back(CHUNK_NORMAL, 0, zip_file, zip_file->size()); + // For source chunks, we don't need to compose chunks for the metadata. + if (is_source_) { + for (auto& entry : temp_entries) { + if (!AddZipEntryToChunks(handle, entry.first, &entry.second)) { + printf("Failed to add %s to source chunks\n", entry.first.c_str()); + return false; + } + } + return true; } + // For target chunks, add the deflate entries as CHUNK_DEFLATE and the contents between two + // deflate entries as CHUNK_NORMAL. size_t pos = 0; size_t nextentry = 0; - while (pos < zip_file->size()) { + while (pos < file_content_.size()) { if (nextentry < temp_entries.size() && static_cast<off64_t>(pos) == temp_entries[nextentry].second.offset) { - // compose the next deflate chunk. - std::string entryname = temp_entries[nextentry].first; - size_t uncompressed_len = temp_entries[nextentry].second.uncompressed_length; - std::vector<uint8_t> uncompressed_data(uncompressed_len); - if ((ret = ExtractToMemory(handle, &temp_entries[nextentry].second, uncompressed_data.data(), - uncompressed_len)) != 0) { - printf("failed to extract %s with size %zu: %s\n", entryname.c_str(), uncompressed_len, - ErrorCodeString(ret)); - CloseArchive(handle); + // Add the next zip entry. + std::string entry_name = temp_entries[nextentry].first; + if (!AddZipEntryToChunks(handle, entry_name, &temp_entries[nextentry].second)) { + printf("Failed to add %s to target chunks\n", entry_name.c_str()); return false; } - size_t compressed_len = temp_entries[nextentry].second.compressed_length; - ImageChunk curr(CHUNK_DEFLATE, pos, zip_file, compressed_len); - curr.SetEntryName(std::move(entryname)); - curr.SetUncompressedData(std::move(uncompressed_data)); - chunks->push_back(curr); - - pos += compressed_len; + pos += temp_entries[nextentry].second.compressed_length; ++nextentry; continue; } - // Use a normal chunk to take all the data up to the start of the next deflate section. + // Use a normal chunk to take all the data up to the start of the next entry. size_t raw_data_len; if (nextentry < temp_entries.size()) { raw_data_len = temp_entries[nextentry].second.offset - pos; } else { - raw_data_len = zip_file->size() - pos; + raw_data_len = file_content_.size() - pos; } - chunks->emplace_back(CHUNK_NORMAL, pos, zip_file, raw_data_len); + chunks_.emplace_back(CHUNK_NORMAL, pos, &file_content_, raw_data_len); pos += raw_data_len; } - CloseArchive(handle); return true; } -// Read the given file and break it up into chunks, and putting the data in to a vector. -static bool ReadImage(const char* filename, std::vector<ImageChunk>* chunks, - std::vector<uint8_t>* img) { - CHECK(chunks != nullptr && img != nullptr); +bool ZipModeImage::AddZipEntryToChunks(ZipArchiveHandle handle, const std::string& entry_name, + ZipEntry* entry) { + size_t compressed_len = entry->compressed_length; + if (entry->method == kCompressDeflated) { + size_t uncompressed_len = entry->uncompressed_length; + std::vector<uint8_t> uncompressed_data(uncompressed_len); + int ret = ExtractToMemory(handle, entry, uncompressed_data.data(), uncompressed_len); + if (ret != 0) { + printf("failed to extract %s with size %zu: %s\n", entry_name.c_str(), uncompressed_len, + ErrorCodeString(ret)); + return false; + } + ImageChunk curr(CHUNK_DEFLATE, entry->offset, &file_content_, compressed_len); + curr.SetEntryName(entry_name); + curr.SetUncompressedData(std::move(uncompressed_data)); + chunks_.push_back(curr); + } else { + ImageChunk curr(CHUNK_NORMAL, entry->offset, &file_content_, compressed_len); + curr.SetEntryName(entry_name); + chunks_.push_back(curr); + } - android::base::unique_fd fd(open(filename, O_RDONLY)); - if (fd == -1) { - printf("failed to open \"%s\" %s\n", filename, strerror(errno)); + return true; +} + +// EOCD record +// offset 0: signature 0x06054b50, 4 bytes +// offset 4: number of this disk, 2 bytes +// ... +// offset 20: comment length, 2 bytes +// offset 22: comment, n bytes +bool ZipModeImage::GetZipFileSize(size_t* input_file_size) { + if (file_content_.size() < 22) { + printf("file is too small to be a zip file\n"); return false; } - struct stat st; - if (fstat(fd, &st) != 0) { - printf("failed to stat \"%s\": %s\n", filename, strerror(errno)); + + // Look for End of central directory record of the zip file, and calculate the actual + // zip_file size. + for (int i = file_content_.size() - 22; i >= 0; i--) { + if (file_content_[i] == 0x50) { + if (get_unaligned<uint32_t>(&file_content_[i]) == 0x06054b50) { + // double-check: this archive consists of a single "disk". + CHECK_EQ(get_unaligned<uint16_t>(&file_content_[i + 4]), 0); + + uint16_t comment_length = get_unaligned<uint16_t>(&file_content_[i + 20]); + size_t file_size = i + 22 + comment_length; + CHECK_LE(file_size, file_content_.size()); + *input_file_size = file_size; + return true; + } + } + } + + // EOCD not found, this file is likely not a valid zip file. + return false; +} + +bool ZipModeImage::CheckAndProcessChunks(ZipModeImage* tgt_image, ZipModeImage* src_image) { + for (auto& tgt_chunk : *tgt_image) { + if (tgt_chunk.GetType() != CHUNK_DEFLATE) { + continue; + } + + ImageChunk* src_chunk = src_image->FindChunkByName(tgt_chunk.GetEntryName()); + if (src_chunk == nullptr) { + tgt_chunk.ChangeDeflateChunkToNormal(); + } else if (tgt_chunk == *src_chunk) { + // If two deflate chunks are identical (eg, the kernel has not changed between two builds), + // treat them as normal chunks. This makes applypatch much faster -- it can apply a trivial + // patch to the compressed data, rather than uncompressing and recompressing to apply the + // trivial patch to the uncompressed data. + tgt_chunk.ChangeDeflateChunkToNormal(); + src_chunk->ChangeDeflateChunkToNormal(); + } else if (!tgt_chunk.ReconstructDeflateChunk()) { + // We cannot recompress the data and get exactly the same bits as are in the input target + // image. Treat the chunk as a normal non-deflated chunk. + printf("failed to reconstruct target deflate chunk [%s]; treating as normal\n", + tgt_chunk.GetEntryName().c_str()); + + tgt_chunk.ChangeDeflateChunkToNormal(); + src_chunk->ChangeDeflateChunkToNormal(); + } + } + + return true; +} + +bool ZipModeImage::GeneratePatches(ZipModeImage* tgt_image, ZipModeImage* src_image, + const std::string& patch_name) { + // For zips, we only need merge normal chunks for the target: deflated chunks are matched via + // filename, and normal chunks are patched using the entire source file as the source. + tgt_image->MergeAdjacentNormalChunks(); + tgt_image->DumpChunks(); + + printf("Construct patches for %zu chunks...\n", tgt_image->NumOfChunks()); + std::vector<std::vector<uint8_t>> patch_data(tgt_image->NumOfChunks()); + + saidx_t* bsdiff_cache = nullptr; + size_t i = 0; + for (auto& tgt_chunk : *tgt_image) { + ImageChunk* src_chunk = (tgt_chunk.GetType() != CHUNK_DEFLATE) + ? nullptr + : src_image->FindChunkByName(tgt_chunk.GetEntryName()); + + const auto& src_ref = (src_chunk == nullptr) ? src_image->PseudoSource() : *src_chunk; + saidx_t** bsdiff_cache_ptr = (src_chunk == nullptr) ? &bsdiff_cache : nullptr; + + if (!tgt_chunk.MakePatch(src_ref, &patch_data[i], bsdiff_cache_ptr)) { + printf("Failed to generate patch, name: %s\n", tgt_chunk.GetEntryName().c_str()); + return false; + } + + printf("patch %3zu is %zu bytes (of %zu)\n", i, patch_data[i].size(), + tgt_chunk.GetRawDataLength()); + i++; + } + free(bsdiff_cache); + + android::base::unique_fd patch_fd( + open(patch_name.c_str(), O_CREAT | O_WRONLY | O_TRUNC, S_IRUSR | S_IWUSR)); + if (patch_fd == -1) { + printf("failed to open \"%s\": %s\n", patch_name.c_str(), strerror(errno)); return false; } - size_t sz = static_cast<size_t>(st.st_size); - img->resize(sz); - if (!android::base::ReadFully(fd, img->data(), sz)) { - printf("failed to read \"%s\" %s\n", filename, strerror(errno)); + return tgt_image->WritePatchDataToFd(patch_data, patch_fd); +} + +class ImageModeImage : public Image { + public: + explicit ImageModeImage(bool is_source) : Image(is_source) {} + + // Initialize the image chunks list by searching the magic numbers in an image file. + bool Initialize(const std::string& filename) override; + + // In Image Mode, verify that the source and target images have the same chunk structure (ie, the + // same sequence of deflate and normal chunks). + static bool CheckAndProcessChunks(ImageModeImage* tgt_image, ImageModeImage* src_image); + + // In image mode, generate patches against the given source chunks and bonus_data; write the + // result to |patch_name|. + static bool GeneratePatches(ImageModeImage* tgt_image, ImageModeImage* src_image, + const std::vector<uint8_t>& bonus_data, const std::string& patch_name); +}; + +bool ImageModeImage::Initialize(const std::string& filename) { + if (!ReadFile(filename, &file_content_)) { return false; } + size_t sz = file_content_.size(); size_t pos = 0; - while (pos < sz) { // 0x00 no header flags, 0x08 deflate compression, 0x1f8b gzip magic number - if (sz - pos >= 4 && get_unaligned<uint32_t>(img->data() + pos) == 0x00088b1f) { + if (sz - pos >= 4 && get_unaligned<uint32_t>(file_content_.data() + pos) == 0x00088b1f) { // 'pos' is the offset of the start of a gzip chunk. size_t chunk_offset = pos; // The remaining data is too small to be a gzip chunk; treat them as a normal chunk. if (sz - pos < GZIP_HEADER_LEN + GZIP_FOOTER_LEN) { - chunks->emplace_back(CHUNK_NORMAL, pos, img, sz - pos); + chunks_.emplace_back(CHUNK_NORMAL, pos, &file_content_, sz - pos); break; } // We need three chunks for the deflated image in total, one normal chunk for the header, // one deflated chunk for the body, and another normal chunk for the footer. - chunks->emplace_back(CHUNK_NORMAL, pos, img, GZIP_HEADER_LEN); + chunks_.emplace_back(CHUNK_NORMAL, pos, &file_content_, GZIP_HEADER_LEN); pos += GZIP_HEADER_LEN; // We must decompress this chunk in order to discover where it ends, and so we can update @@ -657,7 +1000,7 @@ static bool ReadImage(const char* filename, std::vector<ImageChunk>* chunks, strm.zfree = Z_NULL; strm.opaque = Z_NULL; strm.avail_in = sz - pos; - strm.next_in = img->data() + pos; + strm.next_in = file_content_.data() + pos; // -15 means we are decoding a 'raw' deflate stream; zlib will // not expect zlib headers. @@ -700,22 +1043,22 @@ static bool ReadImage(const char* filename, std::vector<ImageChunk>* chunks, printf("Warning: invalid footer position; treating as a nomal chunk\n"); continue; } - size_t footer_size = get_unaligned<uint32_t>(img->data() + footer_index); + size_t footer_size = get_unaligned<uint32_t>(file_content_.data() + footer_index); if (footer_size != uncompressed_len) { printf("Warning: footer size %zu != decompressed size %zu; treating as a nomal chunk\n", footer_size, uncompressed_len); continue; } - ImageChunk body(CHUNK_DEFLATE, pos, img, raw_data_len); + ImageChunk body(CHUNK_DEFLATE, pos, &file_content_, raw_data_len); uncompressed_data.resize(uncompressed_len); body.SetUncompressedData(std::move(uncompressed_data)); - chunks->push_back(body); + chunks_.push_back(body); pos += raw_data_len; // create a normal chunk for the footer - chunks->emplace_back(CHUNK_NORMAL, pos, img, GZIP_FOOTER_LEN); + chunks_.emplace_back(CHUNK_NORMAL, pos, &file_content_, GZIP_FOOTER_LEN); pos += GZIP_FOOTER_LEN; } else { @@ -726,12 +1069,12 @@ static bool ReadImage(const char* filename, std::vector<ImageChunk>* chunks, size_t data_len = 0; while (data_len + pos < sz) { if (data_len + pos + 4 <= sz && - get_unaligned<uint32_t>(img->data() + pos + data_len) == 0x00088b1f) { + get_unaligned<uint32_t>(file_content_.data() + pos + data_len) == 0x00088b1f) { break; } data_len++; } - chunks->emplace_back(CHUNK_NORMAL, pos, img, data_len); + chunks_.emplace_back(CHUNK_NORMAL, pos, &file_content_, data_len); pos += data_len; } @@ -740,346 +1083,178 @@ static bool ReadImage(const char* filename, std::vector<ImageChunk>* chunks, return true; } -/* - * Given source and target chunks, compute a bsdiff patch between them. - * Store the result in the patch_data. - * |bsdiff_cache| can be used to cache the suffix array if the same |src| chunk - * is used repeatedly, pass nullptr if not needed. - */ -static bool MakePatch(const ImageChunk* src, ImageChunk* tgt, std::vector<uint8_t>* patch_data, - saidx_t** bsdiff_cache) { - if (tgt->ChangeChunkToRaw(0)) { - size_t patch_size = tgt->DataLengthForPatch(); - patch_data->resize(patch_size); - std::copy(tgt->DataForPatch(), tgt->DataForPatch() + patch_size, patch_data->begin()); - return true; - } - -#if defined(__ANDROID__) - char ptemp[] = "/data/local/tmp/imgdiff-patch-XXXXXX"; -#else - char ptemp[] = "/tmp/imgdiff-patch-XXXXXX"; -#endif - - int fd = mkstemp(ptemp); - if (fd == -1) { - printf("MakePatch failed to create a temporary file: %s\n", strerror(errno)); +// In Image Mode, verify that the source and target images have the same chunk structure (ie, the +// same sequence of deflate and normal chunks). +bool ImageModeImage::CheckAndProcessChunks(ImageModeImage* tgt_image, ImageModeImage* src_image) { + // In image mode, merge the gzip header and footer in with any adjacent normal chunks. + tgt_image->MergeAdjacentNormalChunks(); + src_image->MergeAdjacentNormalChunks(); + + if (tgt_image->NumOfChunks() != src_image->NumOfChunks()) { + printf("source and target don't have same number of chunks!\n"); + tgt_image->DumpChunks(); + src_image->DumpChunks(); return false; } - close(fd); - - int r = bsdiff::bsdiff(src->DataForPatch(), src->DataLengthForPatch(), tgt->DataForPatch(), - tgt->DataLengthForPatch(), ptemp, bsdiff_cache); - if (r != 0) { - printf("bsdiff() failed: %d\n", r); - return false; + for (size_t i = 0; i < tgt_image->NumOfChunks(); ++i) { + if (tgt_image->Get(i)->GetType() != src_image->Get(i)->GetType()) { + printf("source and target don't have same chunk structure! (chunk %zu)\n", i); + tgt_image->DumpChunks(); + src_image->DumpChunks(); + return false; + } } - android::base::unique_fd patch_fd(open(ptemp, O_RDONLY)); - if (patch_fd == -1) { - printf("failed to open %s: %s\n", ptemp, strerror(errno)); - return false; - } - struct stat st; - if (fstat(patch_fd, &st) != 0) { - printf("failed to stat patch file %s: %s\n", ptemp, strerror(errno)); - return false; - } + for (size_t i = 0; i < tgt_image->NumOfChunks(); ++i) { + auto& tgt_chunk = *tgt_image->Get(i); + auto& src_chunk = *src_image->Get(i); + if (tgt_chunk.GetType() != CHUNK_DEFLATE) { + continue; + } - size_t sz = static_cast<size_t>(st.st_size); - // Change the chunk type to raw if the patch takes less space that way. - if (tgt->ChangeChunkToRaw(sz)) { - unlink(ptemp); - size_t patch_size = tgt->DataLengthForPatch(); - patch_data->resize(patch_size); - std::copy(tgt->DataForPatch(), tgt->DataForPatch() + patch_size, patch_data->begin()); - return true; + // Confirm that we can recompress the data and get exactly the same bits as are in the + // input target image. + if (!tgt_chunk.ReconstructDeflateChunk()) { + printf("failed to reconstruct target deflate chunk %zu [%s]; treating as normal\n", i, + tgt_chunk.GetEntryName().c_str()); + tgt_chunk.ChangeDeflateChunkToNormal(); + src_chunk.ChangeDeflateChunkToNormal(); + continue; + } + + // If two deflate chunks are identical treat them as normal chunks. + if (tgt_chunk == src_chunk) { + tgt_chunk.ChangeDeflateChunkToNormal(); + src_chunk.ChangeDeflateChunkToNormal(); + } } - patch_data->resize(sz); - if (!android::base::ReadFully(patch_fd, patch_data->data(), sz)) { - printf("failed to read \"%s\" %s\n", ptemp, strerror(errno)); + + // For images, we need to maintain the parallel structure of the chunk lists, so do the merging + // in both the source and target lists. + tgt_image->MergeAdjacentNormalChunks(); + src_image->MergeAdjacentNormalChunks(); + if (tgt_image->NumOfChunks() != src_image->NumOfChunks()) { + // This shouldn't happen. + printf("merging normal chunks went awry\n"); return false; } - unlink(ptemp); - tgt->SetSourceInfo(*src); - return true; } -/* - * Look for runs of adjacent normal chunks and compress them down into - * a single chunk. (Such runs can be produced when deflate chunks are - * changed to normal chunks.) - */ -static void MergeAdjacentNormalChunks(std::vector<ImageChunk>* chunks) { - size_t merged_last = 0, cur = 0; - while (cur < chunks->size()) { - // Look for normal chunks adjacent to the current one. If such chunk exists, extend the - // length of the current normal chunk. - size_t to_check = cur + 1; - while (to_check < chunks->size() && chunks->at(cur).IsAdjacentNormal(chunks->at(to_check))) { - chunks->at(cur).MergeAdjacentNormal(chunks->at(to_check)); - to_check++; +// In image mode, generate patches against the given source chunks and bonus_data; write the +// result to |patch_name|. +bool ImageModeImage::GeneratePatches(ImageModeImage* tgt_image, ImageModeImage* src_image, + const std::vector<uint8_t>& bonus_data, + const std::string& patch_name) { + printf("Construct patches for %zu chunks...\n", tgt_image->NumOfChunks()); + std::vector<std::vector<uint8_t>> patch_data(tgt_image->NumOfChunks()); + + for (size_t i = 0; i < tgt_image->NumOfChunks(); i++) { + auto& tgt_chunk = *tgt_image->Get(i); + auto& src_chunk = *src_image->Get(i); + + if (i == 1 && !bonus_data.empty()) { + printf(" using %zu bytes of bonus data for chunk %zu\n", bonus_data.size(), i); + src_chunk.SetBonusData(bonus_data); } - if (merged_last != cur) { - chunks->at(merged_last) = std::move(chunks->at(cur)); + if (!tgt_chunk.MakePatch(src_chunk, &patch_data[i], nullptr)) { + printf("Failed to generate patch for target chunk %zu: ", i); + return false; } - merged_last++; - cur = to_check; - } - if (merged_last < chunks->size()) { - chunks->erase(chunks->begin() + merged_last, chunks->end()); + printf("patch %3zu is %zu bytes (of %zu)\n", i, patch_data[i].size(), + tgt_chunk.GetRawDataLength()); } -} -static ImageChunk* FindChunkByName(const std::string& name, std::vector<ImageChunk>& chunks) { - for (size_t i = 0; i < chunks.size(); ++i) { - if (chunks[i].GetType() == CHUNK_DEFLATE && chunks[i].GetEntryName() == name) { - return &chunks[i]; - } + android::base::unique_fd patch_fd( + open(patch_name.c_str(), O_CREAT | O_WRONLY | O_TRUNC, S_IRUSR | S_IWUSR)); + if (patch_fd == -1) { + printf("failed to open \"%s\": %s\n", patch_name.c_str(), strerror(errno)); + return false; } - return nullptr; -} -static void DumpChunks(const std::vector<ImageChunk>& chunks) { - for (size_t i = 0; i < chunks.size(); ++i) { - printf("chunk %zu: ", i); - chunks[i].Dump(); - } + return tgt_image->WritePatchDataToFd(patch_data, patch_fd); } int imgdiff(int argc, const char** argv) { bool zip_mode = false; + std::vector<uint8_t> bonus_data; - if (argc >= 2 && strcmp(argv[1], "-z") == 0) { - zip_mode = true; - --argc; - ++argv; - } + int opt; + optind = 1; // Reset the getopt state so that we can call it multiple times for test. - std::vector<uint8_t> bonus_data; - if (argc >= 3 && strcmp(argv[1], "-b") == 0) { - android::base::unique_fd fd(open(argv[2], O_RDONLY)); - if (fd == -1) { - printf("failed to open bonus file %s: %s\n", argv[2], strerror(errno)); - return 1; - } - struct stat st; - if (fstat(fd, &st) != 0) { - printf("failed to stat bonus file %s: %s\n", argv[2], strerror(errno)); - return 1; - } + while ((opt = getopt(argc, const_cast<char**>(argv), "zb:")) != -1) { + switch (opt) { + case 'z': + zip_mode = true; + break; + case 'b': { + android::base::unique_fd fd(open(optarg, O_RDONLY)); + if (fd == -1) { + printf("failed to open bonus file %s: %s\n", optarg, strerror(errno)); + return 1; + } + struct stat st; + if (fstat(fd, &st) != 0) { + printf("failed to stat bonus file %s: %s\n", optarg, strerror(errno)); + return 1; + } - size_t bonus_size = st.st_size; - bonus_data.resize(bonus_size); - if (!android::base::ReadFully(fd, bonus_data.data(), bonus_size)) { - printf("failed to read bonus file %s: %s\n", argv[2], strerror(errno)); - return 1; + size_t bonus_size = st.st_size; + bonus_data.resize(bonus_size); + if (!android::base::ReadFully(fd, bonus_data.data(), bonus_size)) { + printf("failed to read bonus file %s: %s\n", optarg, strerror(errno)); + return 1; + } + break; + } + default: + printf("unexpected opt: %s\n", optarg); + return 2; } - - argc -= 2; - argv += 2; } - if (argc != 4) { - printf("usage: %s [-z] [-b <bonus-file>] <src-img> <tgt-img> <patch-file>\n", - argv[0]); + if (argc - optind != 3) { + printf("usage: %s [-z] [-b <bonus-file>] <src-img> <tgt-img> <patch-file>\n", argv[0]); return 2; } - std::vector<ImageChunk> src_chunks; - std::vector<ImageChunk> tgt_chunks; - std::vector<uint8_t> src_file; - std::vector<uint8_t> tgt_file; - if (zip_mode) { - if (!ReadZip(argv[1], &src_chunks, &src_file, true)) { - printf("failed to break apart source zip file\n"); + ZipModeImage src_image(true); + ZipModeImage tgt_image(false); + + if (!src_image.Initialize(argv[optind])) { return 1; } - if (!ReadZip(argv[2], &tgt_chunks, &tgt_file, false)) { - printf("failed to break apart target zip file\n"); + if (!tgt_image.Initialize(argv[optind + 1])) { return 1; } - } else { - if (!ReadImage(argv[1], &src_chunks, &src_file)) { - printf("failed to break apart source image\n"); + + if (!ZipModeImage::CheckAndProcessChunks(&tgt_image, &src_image)) { return 1; } - if (!ReadImage(argv[2], &tgt_chunks, &tgt_file)) { - printf("failed to break apart target image\n"); + // Compute bsdiff patches for each chunk's data (the uncompressed data, in the case of + // deflate chunks). + if (!ZipModeImage::GeneratePatches(&tgt_image, &src_image, argv[optind + 2])) { return 1; } + } else { + ImageModeImage src_image(true); + ImageModeImage tgt_image(false); - // Verify that the source and target images have the same chunk - // structure (ie, the same sequence of deflate and normal chunks). - - // Merge the gzip header and footer in with any adjacent normal chunks. - MergeAdjacentNormalChunks(&tgt_chunks); - MergeAdjacentNormalChunks(&src_chunks); - - if (src_chunks.size() != tgt_chunks.size()) { - printf("source and target don't have same number of chunks!\n"); - printf("source chunks:\n"); - DumpChunks(src_chunks); - printf("target chunks:\n"); - DumpChunks(tgt_chunks); + if (!src_image.Initialize(argv[optind])) { return 1; } - for (size_t i = 0; i < src_chunks.size(); ++i) { - if (src_chunks[i].GetType() != tgt_chunks[i].GetType()) { - printf("source and target don't have same chunk structure! (chunk %zu)\n", i); - printf("source chunks:\n"); - DumpChunks(src_chunks); - printf("target chunks:\n"); - DumpChunks(tgt_chunks); - return 1; - } - } - } - - for (size_t i = 0; i < tgt_chunks.size(); ++i) { - if (tgt_chunks[i].GetType() == CHUNK_DEFLATE) { - // Confirm that given the uncompressed chunk data in the target, we - // can recompress it and get exactly the same bits as are in the - // input target image. If this fails, treat the chunk as a normal - // non-deflated chunk. - if (!tgt_chunks[i].ReconstructDeflateChunk()) { - printf("failed to reconstruct target deflate chunk %zu [%s]; treating as normal\n", i, - tgt_chunks[i].GetEntryName().c_str()); - tgt_chunks[i].ChangeDeflateChunkToNormal(); - if (zip_mode) { - ImageChunk* src = FindChunkByName(tgt_chunks[i].GetEntryName(), src_chunks); - if (src != nullptr) { - src->ChangeDeflateChunkToNormal(); - } - } else { - src_chunks[i].ChangeDeflateChunkToNormal(); - } - continue; - } - - // If two deflate chunks are identical (eg, the kernel has not - // changed between two builds), treat them as normal chunks. - // This makes applypatch much faster -- it can apply a trivial - // patch to the compressed data, rather than uncompressing and - // recompressing to apply the trivial patch to the uncompressed - // data. - ImageChunk* src; - if (zip_mode) { - src = FindChunkByName(tgt_chunks[i].GetEntryName(), src_chunks); - } else { - src = &src_chunks[i]; - } - - if (src == nullptr) { - tgt_chunks[i].ChangeDeflateChunkToNormal(); - } else if (tgt_chunks[i] == *src) { - tgt_chunks[i].ChangeDeflateChunkToNormal(); - src->ChangeDeflateChunkToNormal(); - } - } - } - - // Merging neighboring normal chunks. - if (zip_mode) { - // For zips, we only need to do this to the target: deflated - // chunks are matched via filename, and normal chunks are patched - // using the entire source file as the source. - MergeAdjacentNormalChunks(&tgt_chunks); - - } else { - // For images, we need to maintain the parallel structure of the - // chunk lists, so do the merging in both the source and target - // lists. - MergeAdjacentNormalChunks(&tgt_chunks); - MergeAdjacentNormalChunks(&src_chunks); - if (src_chunks.size() != tgt_chunks.size()) { - // This shouldn't happen. - printf("merging normal chunks went awry\n"); + if (!tgt_image.Initialize(argv[optind + 1])) { return 1; } - } - - // Compute bsdiff patches for each chunk's data (the uncompressed - // data, in the case of deflate chunks). - - DumpChunks(src_chunks); - printf("Construct patches for %zu chunks...\n", tgt_chunks.size()); - std::vector<std::vector<uint8_t>> patch_data(tgt_chunks.size()); - saidx_t* bsdiff_cache = nullptr; - for (size_t i = 0; i < tgt_chunks.size(); ++i) { - if (zip_mode) { - ImageChunk* src; - if (tgt_chunks[i].GetType() == CHUNK_DEFLATE && - (src = FindChunkByName(tgt_chunks[i].GetEntryName(), src_chunks))) { - if (!MakePatch(src, &tgt_chunks[i], &patch_data[i], nullptr)) { - printf("Failed to generate patch for target chunk %zu: ", i); - return 1; - } - } else { - if (!MakePatch(&src_chunks[0], &tgt_chunks[i], &patch_data[i], &bsdiff_cache)) { - printf("Failed to generate patch for target chunk %zu: ", i); - return 1; - } - } - } else { - if (i == 1 && !bonus_data.empty()) { - printf(" using %zu bytes of bonus data for chunk %zu\n", bonus_data.size(), i); - src_chunks[i].SetBonusData(bonus_data); - } - - if (!MakePatch(&src_chunks[i], &tgt_chunks[i], &patch_data[i], nullptr)) { - printf("Failed to generate patch for target chunk %zu: ", i); - return 1; - } + if (!ImageModeImage::CheckAndProcessChunks(&tgt_image, &src_image)) { + return 1; } - printf("patch %3zu is %zu bytes (of %zu)\n", i, patch_data[i].size(), - src_chunks[i].GetRawDataLength()); - } - - if (bsdiff_cache != nullptr) { - free(bsdiff_cache); - } - - // Figure out how big the imgdiff file header is going to be, so - // that we can correctly compute the offset of each bsdiff patch - // within the file. - - size_t total_header_size = 12; - for (size_t i = 0; i < tgt_chunks.size(); ++i) { - total_header_size += tgt_chunks[i].GetHeaderSize(patch_data[i].size()); - } - - size_t offset = total_header_size; - - android::base::unique_fd patch_fd(open(argv[3], O_CREAT | O_WRONLY | O_TRUNC, S_IRUSR | S_IWUSR)); - if (patch_fd == -1) { - printf("failed to open \"%s\": %s\n", argv[3], strerror(errno)); - return 1; - } - - // Write out the headers. - if (!android::base::WriteStringToFd("IMGDIFF2", patch_fd)) { - printf("failed to write \"IMGDIFF2\" to \"%s\": %s\n", argv[3], strerror(errno)); - return 1; - } - Write4(patch_fd, static_cast<int32_t>(tgt_chunks.size())); - for (size_t i = 0; i < tgt_chunks.size(); ++i) { - printf("chunk %zu: ", i); - offset = tgt_chunks[i].WriteHeaderToFd(patch_fd, patch_data[i], offset); - } - - // Append each chunk's bsdiff patch, in order. - for (size_t i = 0; i < tgt_chunks.size(); ++i) { - if (tgt_chunks[i].GetType() != CHUNK_RAW) { - if (!android::base::WriteFully(patch_fd, patch_data[i].data(), patch_data[i].size())) { - CHECK(false) << "failed to write " << patch_data[i].size() << " bytes patch for chunk " - << i; - } + if (!ImageModeImage::GeneratePatches(&tgt_image, &src_image, bonus_data, argv[optind + 2])) { + return 1; } } |