Revamp dexlayout writing functions
Added some stream abstractions to make it easier to split apart
the main part of the dex file compared to the data one.
Moved to using a vector based stream instead of a mem_map one.
Motivations:
Make it easy to separate data into a separate stream for multidex data
deduping.
Remove upper bounds on dex expansion that would SIGSEGV if the writer
went over the limit.
Bug: 72051652
Bug: 63756964
Test: test-art-host
Change-Id: Ic622a4142b161566d149166a1767434ff4cc7fec
diff --git a/dexlayout/dex_container.h b/dexlayout/dex_container.h
new file mode 100644
index 0000000..7c426cb
--- /dev/null
+++ b/dexlayout/dex_container.h
@@ -0,0 +1,80 @@
+/*
+ * Copyright (C) 2018 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.
+ *
+ * Header file of an in-memory representation of DEX files.
+ */
+
+#ifndef ART_DEXLAYOUT_DEX_CONTAINER_H_
+#define ART_DEXLAYOUT_DEX_CONTAINER_H_
+
+#include <vector>
+
+namespace art {
+
+// Dex container holds the artifacts produced by dexlayout and contains up to two sections: a main
+// section and a data section.
+// This container may also hold metadata used for multi dex deduplication in the future.
+class DexContainer {
+ public:
+ virtual ~DexContainer() {}
+
+ class Section {
+ public:
+ virtual ~Section() {}
+
+ // Returns the start of the memory region.
+ virtual uint8_t* Begin() = 0;
+
+ // Size in bytes.
+ virtual size_t Size() const = 0;
+
+ // Resize the backing storage.
+ virtual void Resize(size_t size) = 0;
+
+ // Returns the end of the memory region.
+ uint8_t* End() {
+ return Begin() + Size();
+ }
+ };
+
+ // Vector backed section.
+ class VectorSection : public Section {
+ public:
+ virtual ~VectorSection() {}
+
+ uint8_t* Begin() OVERRIDE {
+ return &data_[0];
+ }
+
+ size_t Size() const OVERRIDE {
+ return data_.size();
+ }
+
+ void Resize(size_t size) OVERRIDE {
+ data_.resize(size, 0u);
+ }
+
+ private:
+ std::vector<uint8_t> data_;
+ };
+
+ virtual Section* GetMainSection() = 0;
+ virtual Section* GetDataSection() = 0;
+ virtual bool IsCompactDexContainer() const = 0;
+};
+
+} // namespace art
+
+#endif // ART_DEXLAYOUT_DEX_CONTAINER_H_