| /* |
| * Copyright (C) 2015 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #include "format/binary/XmlFlattener.h" |
| |
| #include <algorithm> |
| #include <map> |
| #include <vector> |
| |
| #include "android-base/logging.h" |
| #include "android-base/macros.h" |
| #include "androidfw/ResourceTypes.h" |
| #include "utils/misc.h" |
| |
| #include "ResourceUtils.h" |
| #include "SdkConstants.h" |
| #include "ValueVisitor.h" |
| #include "format/binary/ChunkWriter.h" |
| #include "format/binary/ResourceTypeExtensions.h" |
| #include "xml/XmlDom.h" |
| |
| using namespace android; |
| |
| using ::aapt::ResourceUtils::StringBuilder; |
| |
| namespace aapt { |
| |
| namespace { |
| |
| constexpr uint32_t kLowPriority = 0xffffffffu; |
| |
| static bool cmp_xml_attribute_by_id(const xml::Attribute* a, const xml::Attribute* b) { |
| if (a->compiled_attribute && a->compiled_attribute.value().id) { |
| if (b->compiled_attribute && b->compiled_attribute.value().id) { |
| return a->compiled_attribute.value().id.value() < b->compiled_attribute.value().id.value(); |
| } |
| return true; |
| } else if (!b->compiled_attribute) { |
| int diff = a->namespace_uri.compare(b->namespace_uri); |
| if (diff < 0) { |
| return true; |
| } else if (diff > 0) { |
| return false; |
| } |
| return a->name < b->name; |
| } |
| return false; |
| } |
| |
| class XmlFlattenerVisitor : public xml::ConstVisitor { |
| public: |
| using xml::ConstVisitor::Visit; |
| |
| StringPool pool; |
| std::map<uint8_t, StringPool> package_pools; |
| |
| struct StringFlattenDest { |
| StringPool::Ref ref; |
| ResStringPool_ref* dest; |
| }; |
| |
| std::vector<StringFlattenDest> string_refs; |
| |
| XmlFlattenerVisitor(BigBuffer* buffer, XmlFlattenerOptions options) |
| : buffer_(buffer), options_(options) { |
| } |
| |
| void Visit(const xml::Text* node) override { |
| if (util::TrimWhitespace(node->text).empty()) { |
| // Skip whitespace only text nodes. |
| return; |
| } |
| |
| ChunkWriter writer(buffer_); |
| ResXMLTree_node* flat_node = writer.StartChunk<ResXMLTree_node>(RES_XML_CDATA_TYPE); |
| flat_node->lineNumber = util::HostToDevice32(node->line_number); |
| flat_node->comment.index = util::HostToDevice32(-1); |
| |
| ResXMLTree_cdataExt* flat_text = writer.NextBlock<ResXMLTree_cdataExt>(); |
| |
| // Process plain strings to make sure they get properly escaped. |
| StringBuilder builder; |
| builder.AppendText(node->text); |
| AddString(builder.to_string(), kLowPriority, &flat_text->data); |
| |
| writer.Finish(); |
| } |
| |
| void Visit(const xml::Element* node) override { |
| for (const xml::NamespaceDecl& decl : node->namespace_decls) { |
| // Skip dedicated tools namespace. |
| if (decl.uri != xml::kSchemaTools) { |
| WriteNamespace(decl, android::RES_XML_START_NAMESPACE_TYPE); |
| } |
| } |
| |
| { |
| ChunkWriter start_writer(buffer_); |
| ResXMLTree_node* flat_node = |
| start_writer.StartChunk<ResXMLTree_node>(RES_XML_START_ELEMENT_TYPE); |
| flat_node->lineNumber = util::HostToDevice32(node->line_number); |
| flat_node->comment.index = util::HostToDevice32(-1); |
| |
| ResXMLTree_attrExt* flat_elem = start_writer.NextBlock<ResXMLTree_attrExt>(); |
| |
| // A missing namespace must be null, not an empty string. Otherwise the runtime complains. |
| AddString(node->namespace_uri, kLowPriority, &flat_elem->ns, |
| true /* treat_empty_string_as_null */); |
| AddString(node->name, kLowPriority, &flat_elem->name, true /* treat_empty_string_as_null */); |
| |
| flat_elem->attributeStart = util::HostToDevice16(sizeof(*flat_elem)); |
| flat_elem->attributeSize = util::HostToDevice16(sizeof(ResXMLTree_attribute)); |
| |
| WriteAttributes(node, flat_elem, &start_writer); |
| |
| start_writer.Finish(); |
| } |
| |
| xml::ConstVisitor::Visit(node); |
| |
| { |
| ChunkWriter end_writer(buffer_); |
| ResXMLTree_node* flat_end_node = |
| end_writer.StartChunk<ResXMLTree_node>(RES_XML_END_ELEMENT_TYPE); |
| flat_end_node->lineNumber = util::HostToDevice32(node->line_number); |
| flat_end_node->comment.index = util::HostToDevice32(-1); |
| |
| ResXMLTree_endElementExt* flat_end_elem = end_writer.NextBlock<ResXMLTree_endElementExt>(); |
| AddString(node->namespace_uri, kLowPriority, &flat_end_elem->ns, |
| true /* treat_empty_string_as_null */); |
| AddString(node->name, kLowPriority, &flat_end_elem->name); |
| |
| end_writer.Finish(); |
| } |
| |
| for (auto iter = node->namespace_decls.rbegin(); iter != node->namespace_decls.rend(); ++iter) { |
| // Skip dedicated tools namespace. |
| if (iter->uri != xml::kSchemaTools) { |
| WriteNamespace(*iter, android::RES_XML_END_NAMESPACE_TYPE); |
| } |
| } |
| } |
| |
| private: |
| DISALLOW_COPY_AND_ASSIGN(XmlFlattenerVisitor); |
| |
| // We are adding strings to a StringPool whose strings will be sorted and merged with other |
| // string pools. That means we can't encode the ID of a string directly. Instead, we defer the |
| // writing of the ID here, until after the StringPool is merged and sorted. |
| void AddString(const StringPiece& str, uint32_t priority, android::ResStringPool_ref* dest, |
| bool treat_empty_string_as_null = false) { |
| if (str.empty() && treat_empty_string_as_null) { |
| // Some parts of the runtime treat null differently than empty string. |
| dest->index = util::DeviceToHost32(-1); |
| } else { |
| string_refs.push_back( |
| StringFlattenDest{pool.MakeRef(str, StringPool::Context(priority)), dest}); |
| } |
| } |
| |
| // We are adding strings to a StringPool whose strings will be sorted and merged with other |
| // string pools. That means we can't encode the ID of a string directly. Instead, we defer the |
| // writing of the ID here, until after the StringPool is merged and sorted. |
| void AddString(const StringPool::Ref& ref, android::ResStringPool_ref* dest) { |
| string_refs.push_back(StringFlattenDest{ref, dest}); |
| } |
| |
| void WriteNamespace(const xml::NamespaceDecl& decl, uint16_t type) { |
| ChunkWriter writer(buffer_); |
| |
| ResXMLTree_node* flatNode = writer.StartChunk<ResXMLTree_node>(type); |
| flatNode->lineNumber = util::HostToDevice32(decl.line_number); |
| flatNode->comment.index = util::HostToDevice32(-1); |
| |
| ResXMLTree_namespaceExt* flat_ns = writer.NextBlock<ResXMLTree_namespaceExt>(); |
| AddString(decl.prefix, kLowPriority, &flat_ns->prefix); |
| AddString(decl.uri, kLowPriority, &flat_ns->uri); |
| |
| writer.Finish(); |
| } |
| |
| void WriteAttributes(const xml::Element* node, ResXMLTree_attrExt* flat_elem, |
| ChunkWriter* writer) { |
| filtered_attrs_.clear(); |
| filtered_attrs_.reserve(node->attributes.size()); |
| |
| // Filter the attributes. |
| for (const xml::Attribute& attr : node->attributes) { |
| if (attr.namespace_uri != xml::kSchemaTools) { |
| filtered_attrs_.push_back(&attr); |
| } |
| } |
| |
| if (filtered_attrs_.empty()) { |
| return; |
| } |
| |
| const ResourceId kIdAttr(0x010100d0); |
| |
| std::sort(filtered_attrs_.begin(), filtered_attrs_.end(), cmp_xml_attribute_by_id); |
| |
| flat_elem->attributeCount = util::HostToDevice16(filtered_attrs_.size()); |
| |
| ResXMLTree_attribute* flat_attr = |
| writer->NextBlock<ResXMLTree_attribute>(filtered_attrs_.size()); |
| uint16_t attribute_index = 1; |
| for (const xml::Attribute* xml_attr : filtered_attrs_) { |
| // Assign the indices for specific attributes. |
| if (xml_attr->compiled_attribute && xml_attr->compiled_attribute.value().id && |
| xml_attr->compiled_attribute.value().id.value() == kIdAttr) { |
| flat_elem->idIndex = util::HostToDevice16(attribute_index); |
| } else if (xml_attr->namespace_uri.empty()) { |
| if (xml_attr->name == "class") { |
| flat_elem->classIndex = util::HostToDevice16(attribute_index); |
| } else if (xml_attr->name == "style") { |
| flat_elem->styleIndex = util::HostToDevice16(attribute_index); |
| } |
| } |
| attribute_index++; |
| |
| // Add the namespaceUri to the list of StringRefs to encode. Use null if the namespace |
| // is empty (doesn't exist). |
| AddString(xml_attr->namespace_uri, kLowPriority, &flat_attr->ns, |
| true /* treat_empty_string_as_null */); |
| |
| flat_attr->rawValue.index = util::HostToDevice32(-1); |
| |
| if (!xml_attr->compiled_attribute || !xml_attr->compiled_attribute.value().id) { |
| // The attribute has no associated ResourceID, so the string order doesn't matter. |
| AddString(xml_attr->name, kLowPriority, &flat_attr->name); |
| } else { |
| // Attribute names are stored without packages, but we use |
| // their StringPool index to lookup their resource IDs. |
| // This will cause collisions, so we can't dedupe |
| // attribute names from different packages. We use separate |
| // pools that we later combine. |
| // |
| // Lookup the StringPool for this package and make the reference there. |
| const xml::AaptAttribute& aapt_attr = xml_attr->compiled_attribute.value(); |
| |
| StringPool::Ref name_ref = package_pools[aapt_attr.id.value().package_id()].MakeRef( |
| xml_attr->name, StringPool::Context(aapt_attr.id.value().id)); |
| |
| // Add it to the list of strings to flatten. |
| AddString(name_ref, &flat_attr->name); |
| } |
| |
| std::string processed_str; |
| Maybe<StringPiece> compiled_text; |
| if (xml_attr->compiled_value != nullptr) { |
| // Make sure we're not flattening a String. A String can be referencing a string from |
| // a different StringPool than we're using here to build the binary XML. |
| String* string_value = ValueCast<String>(xml_attr->compiled_value.get()); |
| if (string_value != nullptr) { |
| // Mark the String's text as needing to be serialized. |
| compiled_text = StringPiece(*string_value->value); |
| } else { |
| // Serialize this compiled value safely. |
| CHECK(xml_attr->compiled_value->Flatten(&flat_attr->typedValue)); |
| } |
| } else { |
| // There is no compiled value, so treat the raw string as compiled, once it is processed to |
| // make sure escape sequences are properly interpreted. |
| processed_str = |
| StringBuilder(true /*preserve_spaces*/).AppendText(xml_attr->value).to_string(); |
| compiled_text = StringPiece(processed_str); |
| } |
| |
| if (compiled_text) { |
| // Write out the compiled text and raw_text. |
| flat_attr->typedValue.dataType = android::Res_value::TYPE_STRING; |
| AddString(compiled_text.value(), kLowPriority, |
| reinterpret_cast<ResStringPool_ref*>(&flat_attr->typedValue.data)); |
| if (options_.keep_raw_values) { |
| AddString(xml_attr->value, kLowPriority, &flat_attr->rawValue); |
| } else { |
| AddString(compiled_text.value(), kLowPriority, &flat_attr->rawValue); |
| } |
| } else if (options_.keep_raw_values && !xml_attr->value.empty()) { |
| AddString(xml_attr->value, kLowPriority, &flat_attr->rawValue); |
| } |
| |
| flat_attr->typedValue.size = util::HostToDevice16(sizeof(flat_attr->typedValue)); |
| flat_attr++; |
| } |
| } |
| |
| BigBuffer* buffer_; |
| XmlFlattenerOptions options_; |
| |
| // Scratch vector to filter attributes. We avoid allocations making this a member. |
| std::vector<const xml::Attribute*> filtered_attrs_; |
| }; |
| |
| } // namespace |
| |
| bool XmlFlattener::Flatten(IAaptContext* context, const xml::Node* node) { |
| BigBuffer node_buffer(1024); |
| XmlFlattenerVisitor visitor(&node_buffer, options_); |
| node->Accept(&visitor); |
| |
| // Merge the package pools into the main pool. |
| for (auto& package_pool_entry : visitor.package_pools) { |
| visitor.pool.Merge(std::move(package_pool_entry.second)); |
| } |
| |
| // Sort the string pool so that attribute resource IDs show up first. |
| visitor.pool.Sort([](const StringPool::Context& a, const StringPool::Context& b) -> int { |
| return util::compare(a.priority, b.priority); |
| }); |
| |
| // Now we flatten the string pool references into the correct places. |
| for (const auto& ref_entry : visitor.string_refs) { |
| ref_entry.dest->index = util::HostToDevice32(ref_entry.ref.index()); |
| } |
| |
| // Write the XML header. |
| ChunkWriter xml_header_writer(buffer_); |
| xml_header_writer.StartChunk<ResXMLTree_header>(RES_XML_TYPE); |
| |
| // Flatten the StringPool. |
| if (options_.use_utf16) { |
| StringPool::FlattenUtf16(buffer_, visitor.pool); |
| } else { |
| StringPool::FlattenUtf8(buffer_, visitor.pool); |
| } |
| |
| { |
| // Write the array of resource IDs, indexed by StringPool order. |
| ChunkWriter res_id_map_writer(buffer_); |
| res_id_map_writer.StartChunk<ResChunk_header>(RES_XML_RESOURCE_MAP_TYPE); |
| for (const auto& str : visitor.pool.strings()) { |
| ResourceId id(str->context.priority); |
| if (str->context.priority == kLowPriority || !id.is_valid()) { |
| // When we see the first non-resource ID, we're done. |
| break; |
| } |
| *res_id_map_writer.NextBlock<uint32_t>() = util::HostToDevice32(id.id); |
| } |
| res_id_map_writer.Finish(); |
| } |
| |
| // Move the nodeBuffer and append it to the out buffer. |
| buffer_->AppendBuffer(std::move(node_buffer)); |
| |
| // Finish the xml header. |
| xml_header_writer.Finish(); |
| return true; |
| } |
| |
| bool XmlFlattener::Consume(IAaptContext* context, const xml::XmlResource* resource) { |
| if (!resource->root) { |
| return false; |
| } |
| return Flatten(context, resource->root.get()); |
| } |
| |
| } // namespace aapt |