Missed new files in last commit
Review URL: http://codereview.chromium.org/465067
git-svn-id: svn://chrome-svn/chromeos/trunk@336 06c00378-0e64-4dae-be16-12b19f9950a1
diff --git a/delta_diff_generator.cc b/delta_diff_generator.cc
new file mode 100644
index 0000000..6f352c7
--- /dev/null
+++ b/delta_diff_generator.cc
@@ -0,0 +1,423 @@
+// Copyright (c) 2009 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "update_engine/delta_diff_generator.h"
+#include <dirent.h>
+#include <endian.h>
+#include <errno.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <algorithm>
+#include <vector>
+#include <tr1/memory>
+#include <zlib.h>
+#include "chromeos/obsolete_logging.h"
+#include "base/scoped_ptr.h"
+#include "update_engine/delta_diff_parser.h"
+#include "update_engine/gzip.h"
+#include "update_engine/subprocess.h"
+#include "update_engine/utils.h"
+
+using std::vector;
+using std::tr1::shared_ptr;
+using chromeos_update_engine::DeltaArchiveManifest;
+
+namespace chromeos_update_engine {
+
+namespace {
+// These structs and methods are helpers for EncodeDataToDeltaFile()
+
+// Before moving the data into a proto buffer, the data is stored in
+// memory in these Node and Child structures.
+
+// Each Node struct represents a file on disk (which can be regular file,
+// directory, fifo, socket, symlink, etc). Nodes that contain children
+// (just directories) will have a vector of Child objects. Each child
+// object has a filename and a pointer to the associated Node. Thus,
+// filenames for files are stored with their parents, not as part of
+// the file itself.
+
+// These structures are easier to work with than the protobuf format
+// when adding files. When generating a delta file, we add an entry
+// for each file to a root Node object. Then, we sort each Node's
+// children vector so the children are stored alphabetically. Then,
+// we assign an index value to the idx field of each Node by a preorder
+// tree traversal. The index value assigned to a Node is the index it
+// will have in the DeltaArchiveManifest protobuf.
+// Finally, we add each Node to a DeltaArchiveManifest protobuf.
+
+struct Node;
+
+struct Child {
+ Child(const string& the_name,
+ Node* the_node)
+ : name(the_name),
+ node(the_node) {}
+ string name;
+ // Use shared_ptr here rather than scoped_ptr b/c this struct will be copied
+ // in stl containers
+ scoped_ptr<Node> node;
+};
+
+// For the C++ sort() function.
+struct ChildLessThan {
+ bool operator()(const shared_ptr<Child>& a, const shared_ptr<Child>& b) {
+ return a->name < b->name;
+ }
+};
+
+struct Node {
+ Node()
+ : mode(0),
+ uid(0),
+ gid(0),
+ compressed(false),
+ offset(-1),
+ length(0),
+ idx(0) {}
+
+ mode_t mode;
+ uid_t uid;
+ gid_t gid;
+
+ // data
+ bool compressed;
+ int offset; // -1 means no data
+ int length;
+
+ vector<shared_ptr<Child> > children;
+ int idx;
+};
+
+// This function sets *node's variables to match what's at path.
+// This includes calling this function recursively on all children. Children
+// not on the same device as the original node will not be considered.
+// Returns true on success.
+bool UpdateNodeFromPath(const string& path, Node* node) {
+ // Set metadata
+ struct stat stbuf;
+ TEST_AND_RETURN_FALSE_ERRNO(lstat(path.c_str(), &stbuf) == 0);
+ const dev_t dev = stbuf.st_dev;
+ node->mode = stbuf.st_mode;
+ node->uid = stbuf.st_uid;
+ node->gid = stbuf.st_gid;
+ if (!S_ISDIR(node->mode)) {
+ return true;
+ }
+
+ DIR* dir = opendir(path.c_str());
+ TEST_AND_RETURN_FALSE(dir);
+
+ struct dirent entry;
+ struct dirent* dir_entry;
+
+ for (;;) {
+ TEST_AND_RETURN_FALSE_ERRNO(readdir_r(dir, &entry, &dir_entry) == 0);
+ if (!dir_entry) {
+ // done
+ break;
+ }
+ if (!strcmp(".", dir_entry->d_name))
+ continue;
+ if (!strcmp("..", dir_entry->d_name))
+ continue;
+
+ string child_path = path + "/" + dir_entry->d_name;
+ struct stat child_stbuf;
+ TEST_AND_RETURN_FALSE_ERRNO(lstat(child_path.c_str(), &child_stbuf) == 0);
+ // make sure it's on the same dev
+ if (child_stbuf.st_dev != dev)
+ continue;
+ shared_ptr<Child> child(new Child(dir_entry->d_name, new Node));
+ node->children.push_back(child);
+ TEST_AND_RETURN_FALSE(UpdateNodeFromPath(path + "/" + child->name,
+ child->node.get()));
+ }
+ TEST_AND_RETURN_FALSE_ERRNO(closedir(dir) == 0);
+ // Done with all subdirs. sort children.
+ sort(node->children.begin(), node->children.end(), ChildLessThan());
+ return true;
+}
+
+// We go through n setting the index value of each Node to
+// *next_index_value, then increment next_index_value.
+// We then recursively assign index values to children.
+// The first caller should call this with *next_index_value == 0 and
+// the root Node, thus setting the root Node's index to 0.
+void PopulateChildIndexes(Node* n, int* next_index_value) {
+ n->idx = (*next_index_value)++;
+ for (unsigned int i = 0; i < n->children.size(); i++) {
+ PopulateChildIndexes(n->children[i]->node.get(), next_index_value);
+ }
+}
+
+// This converts a Node tree rooted at n into a DeltaArchiveManifest.
+void NodeToDeltaArchiveManifest(Node* n, DeltaArchiveManifest* archive) {
+ DeltaArchiveManifest_File *f = archive->add_files();
+ f->set_mode(n->mode);
+ f->set_uid(n->uid);
+ f->set_gid(n->gid);
+ if (!S_ISDIR(n->mode))
+ return;
+ for (unsigned int i = 0; i < n->children.size(); i++) {
+ DeltaArchiveManifest_File_Child* child = f->add_children();
+ child->set_name(n->children[i]->name);
+ child->set_index(n->children[i]->node->idx);
+ }
+ for (unsigned int i = 0; i < n->children.size(); i++) {
+ NodeToDeltaArchiveManifest(n->children[i]->node.get(), archive);
+ }
+}
+
+} // namespace {}
+
+// For each file in archive, write a delta for it into out_file
+// and update 'file' to refer to the delta.
+// This is a recursive function. Returns true on success.
+bool DeltaDiffGenerator::WriteFileDiffsToDeltaFile(
+ DeltaArchiveManifest* archive,
+ DeltaArchiveManifest_File* file,
+ const std::string& file_name,
+ const std::string& old_path,
+ const std::string& new_path,
+ FileWriter* out_file_writer,
+ int* out_file_length) {
+ TEST_AND_RETURN_FALSE(file->has_mode());
+
+ // Stat the actual file, too
+ struct stat stbuf;
+ TEST_AND_RETURN_FALSE_ERRNO(lstat((new_path + "/" + file_name).c_str(),
+ &stbuf) == 0);
+ TEST_AND_RETURN_FALSE(stbuf.st_mode == file->mode());
+
+ // See if we're a directory or not
+ if (S_ISDIR(file->mode())) {
+ for (int i = 0; i < file->children_size(); i++) {
+ DeltaArchiveManifest_File_Child* child = file->mutable_children(i);
+ DeltaArchiveManifest_File* child_file =
+ archive->mutable_files(child->index());
+ TEST_AND_RETURN_FALSE(WriteFileDiffsToDeltaFile(
+ archive,
+ child_file,
+ child->name(),
+ old_path + "/" + file_name,
+ new_path + "/" + file_name,
+ out_file_writer,
+ out_file_length));
+ }
+ return true;
+ }
+
+ if (S_ISFIFO(file->mode()) || S_ISSOCK(file->mode())) {
+ // These don't store any additional data
+ return true;
+ }
+
+ vector<char> data;
+ bool should_compress = true;
+ bool format_set = false;
+ DeltaArchiveManifest_File_DataFormat format;
+ if (S_ISLNK(file->mode())) {
+ LOG(INFO) << "link";
+ TEST_AND_RETURN_FALSE(EncodeLink(new_path + "/" + file_name, &data));
+ } else if (S_ISCHR(file->mode()) || S_ISBLK(file->mode())) {
+ LOG(INFO) << "dev";
+ TEST_AND_RETURN_FALSE(EncodeDev(stbuf, &data));
+ } else if (S_ISREG(file->mode())) {
+ LOG(INFO) << "reg";
+ // regular file. We may use a delta here.
+ TEST_AND_RETURN_FALSE(EncodeFile(old_path, new_path, file_name, &format,
+ &data));
+ should_compress = false;
+ format_set = true;
+ if ((format == DeltaArchiveManifest_File_DataFormat_BSDIFF) ||
+ (format == DeltaArchiveManifest_File_DataFormat_FULL_GZ))
+ TEST_AND_RETURN_FALSE(!data.empty());
+ } else {
+ // Should never get here; unhandled mode type.
+ LOG(ERROR) << "Unhandled mode type: " << file->mode();
+ return false;
+ }
+ LOG(INFO) << "data len: " << data.size();
+ if (!format_set) {
+ // Pick a format now
+ vector<char> compressed_data;
+ TEST_AND_RETURN_FALSE(GzipCompress(data, &compressed_data));
+ if (compressed_data.size() < data.size()) {
+ format = DeltaArchiveManifest_File_DataFormat_FULL_GZ;
+ data.swap(compressed_data);
+ } else {
+ format = DeltaArchiveManifest_File_DataFormat_FULL;
+ }
+ format_set = true;
+ }
+
+ if (!data.empty()) {
+ TEST_AND_RETURN_FALSE(format_set);
+ file->set_data_format(format);
+ file->set_data_offset(*out_file_length);
+ TEST_AND_RETURN_FALSE(static_cast<ssize_t>(data.size()) ==
+ out_file_writer->Write(&data[0], data.size()));
+ file->set_data_length(data.size());
+ *out_file_length += data.size();
+ }
+ return true;
+}
+
+bool DeltaDiffGenerator::EncodeLink(const std::string& path,
+ std::vector<char>* out) {
+ // Store symlink path as file data
+ vector<char> link_data(4096);
+ int rc = readlink(path.c_str(), &link_data[0], link_data.size());
+ TEST_AND_RETURN_FALSE_ERRNO(rc >= 0);
+ link_data.resize(rc);
+ out->swap(link_data);
+ return true;
+}
+
+bool DeltaDiffGenerator::EncodeDev(const struct stat& stbuf,
+ std::vector<char>* out) {
+ LinuxDevice dev;
+ dev.set_major(major(stbuf.st_rdev));
+ dev.set_minor(minor(stbuf.st_rdev));
+ out->resize(dev.ByteSize());
+ TEST_AND_RETURN_FALSE(dev.SerializeToArray(&(*out)[0], out->size()));
+ return true;
+}
+
+// Encode the file at new_path + "/" + file_name. It may be a binary diff
+// based on old_path + "/" + file_name. out_data_format will be set to
+// the format used. out_data_format may not be NULL.
+bool DeltaDiffGenerator::EncodeFile(
+ const string& old_dir,
+ const string& new_dir,
+ const string& file_name,
+ DeltaArchiveManifest_File_DataFormat* out_data_format,
+ vector<char>* out) {
+ TEST_AND_RETURN_FALSE(out_data_format);
+ // First, see the full length:
+ vector<char> full_data;
+ TEST_AND_RETURN_FALSE(utils::ReadFile(new_dir + "/" + file_name, &full_data));
+ vector<char> gz_data;
+ if (!full_data.empty()) {
+ TEST_AND_RETURN_FALSE(GzipCompress(full_data, &gz_data));
+ }
+ vector<char> *ret = NULL;
+
+ if (gz_data.size() < full_data.size()) {
+ *out_data_format = DeltaArchiveManifest_File_DataFormat_FULL_GZ;
+ ret = &gz_data;
+ } else {
+ *out_data_format = DeltaArchiveManifest_File_DataFormat_FULL;
+ ret = &full_data;
+ }
+
+ struct stat old_stbuf;
+ if ((stat((old_dir + "/" + file_name).c_str(), &old_stbuf) < 0) ||
+ (!S_ISREG(old_stbuf.st_mode))) {
+ // stat() failed or old file is not a regular file. Just send back the full
+ // contents
+ *out = *ret;
+ return true;
+ }
+ // We have an old file. Do a binary diff. For now use bsdiff.
+ const string kPatchFile = "/tmp/delta.patch";
+
+ vector<string> cmd;
+ cmd.push_back("/usr/bin/bsdiff");
+ cmd.push_back(old_dir + "/" + file_name);
+ cmd.push_back(new_dir + "/" + file_name);
+ cmd.push_back(kPatchFile);
+
+ int rc = 1;
+ TEST_AND_RETURN_FALSE(Subprocess::SynchronousExec(cmd, &rc));
+ TEST_AND_RETURN_FALSE(rc == 0);
+ vector<char> patch_file;
+ TEST_AND_RETURN_FALSE(utils::ReadFile(kPatchFile, &patch_file));
+ unlink(kPatchFile.c_str());
+
+ if (patch_file.size() < ret->size()) {
+ *out_data_format = DeltaArchiveManifest_File_DataFormat_BSDIFF;
+ ret = &patch_file;
+ }
+
+ *out = *ret;
+ return true;
+}
+
+DeltaArchiveManifest* DeltaDiffGenerator::EncodeMetadataToProtoBuffer(
+ const char* new_path) {
+ Node node;
+ if (!UpdateNodeFromPath(new_path, &node))
+ return NULL;
+ int index = 0;
+ PopulateChildIndexes(&node, &index);
+ DeltaArchiveManifest *ret = new DeltaArchiveManifest;
+ NodeToDeltaArchiveManifest(&node, ret);
+ return ret;
+}
+
+bool DeltaDiffGenerator::EncodeDataToDeltaFile(DeltaArchiveManifest* archive,
+ const std::string& old_path,
+ const std::string& new_path,
+ const std::string& out_file) {
+ DirectFileWriter out_writer;
+ int r = out_writer.Open(out_file.c_str(), O_WRONLY | O_CREAT | O_TRUNC, 0666);
+ TEST_AND_RETURN_FALSE_ERRNO(r >= 0);
+ ScopedFileWriterCloser closer(&out_writer);
+ TEST_AND_RETURN_FALSE(out_writer.Write(DeltaDiffParser::kFileMagic,
+ strlen(DeltaDiffParser::kFileMagic))
+ == static_cast<ssize_t>(
+ strlen(DeltaDiffParser::kFileMagic)));
+ // Write 8 null bytes. This will be filled in w/ the offset of
+ // the protobuf.
+ TEST_AND_RETURN_FALSE(out_writer.Write("\0\0\0\0\0\0\0\0", 8) == 8);
+ // 8 more bytes will be filled w/ the protobuf length.
+ TEST_AND_RETURN_FALSE(out_writer.Write("\0\0\0\0\0\0\0\0", 8) == 8);
+ int out_file_length = strlen(DeltaDiffParser::kFileMagic) + 16;
+
+ TEST_AND_RETURN_FALSE(archive->files_size() > 0);
+ DeltaArchiveManifest_File* file = archive->mutable_files(0);
+
+ TEST_AND_RETURN_FALSE(WriteFileDiffsToDeltaFile(archive,
+ file,
+ "",
+ old_path,
+ new_path,
+ &out_writer,
+ &out_file_length));
+
+ // Finally, write the protobuf to the end of the file
+ string encoded_archive;
+ TEST_AND_RETURN_FALSE(archive->SerializeToString(&encoded_archive));
+
+ // Compress the protobuf (which contains filenames)
+ vector<char> compressed_encoded_archive;
+ TEST_AND_RETURN_FALSE(GzipCompressString(encoded_archive,
+ &compressed_encoded_archive));
+
+ TEST_AND_RETURN_FALSE(out_writer.Write(compressed_encoded_archive.data(),
+ compressed_encoded_archive.size()) ==
+ static_cast<ssize_t>(
+ compressed_encoded_archive.size()));
+
+ // write offset of protobut to just after the file magic
+ int64 big_endian_protobuf_offset = htobe64(out_file_length);
+ TEST_AND_RETURN_FALSE(pwrite(out_writer.fd(),
+ &big_endian_protobuf_offset,
+ sizeof(big_endian_protobuf_offset),
+ strlen(DeltaDiffParser::kFileMagic)) ==
+ sizeof(big_endian_protobuf_offset));
+ // Write the size just after the offset
+ int64 pb_length = htobe64(compressed_encoded_archive.size());
+ TEST_AND_RETURN_FALSE(pwrite(out_writer.fd(),
+ &pb_length,
+ sizeof(pb_length),
+ strlen(DeltaDiffParser::kFileMagic) +
+ sizeof(big_endian_protobuf_offset)) ==
+ sizeof(pb_length));
+ return true;
+}
+
+} // namespace chromeos_update_engine