New version of unwinder.

Bug: 23762183

Test: All unit tests pass.
Change-Id: I0ac69e55af56e1142c0a1ee3715cdc48f2ed3ec3
diff --git a/libunwindstack/Memory.h b/libunwindstack/Memory.h
new file mode 100644
index 0000000..5ab031d
--- /dev/null
+++ b/libunwindstack/Memory.h
@@ -0,0 +1,121 @@
+/*
+ * Copyright (C) 2016 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.
+ */
+
+#ifndef _LIBUNWINDSTACK_MEMORY_H
+#define _LIBUNWINDSTACK_MEMORY_H
+
+#include <stdint.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include <string>
+
+#include <android-base/unique_fd.h>
+
+constexpr bool kMemoryStatsEnabled = true;
+
+class Memory {
+ public:
+  Memory() = default;
+  virtual ~Memory() = default;
+
+  virtual bool ReadString(uint64_t addr, std::string* string, uint64_t max_read = UINT64_MAX);
+
+  virtual bool Read(uint64_t addr, void* dst, size_t size) = 0;
+
+  inline bool Read(uint64_t addr, void* start, void* field, size_t size) {
+    return Read(addr + reinterpret_cast<uintptr_t>(field) - reinterpret_cast<uintptr_t>(start),
+                field, size);
+  }
+
+  inline bool Read32(uint64_t addr, uint32_t* dst) {
+    return Read(addr, dst, sizeof(uint32_t));
+  }
+
+  inline bool Read64(uint64_t addr, uint64_t* dst) {
+    return Read(addr, dst, sizeof(uint64_t));
+  }
+};
+
+class MemoryFileAtOffset : public Memory {
+ public:
+  MemoryFileAtOffset() = default;
+  virtual ~MemoryFileAtOffset();
+
+  bool Init(const std::string& file, uint64_t offset);
+
+  bool Read(uint64_t addr, void* dst, size_t size) override;
+
+ protected:
+  size_t size_ = 0;
+  size_t offset_ = 0;
+  uint8_t* data_ = nullptr;
+};
+
+class MemoryOffline : public MemoryFileAtOffset {
+ public:
+  MemoryOffline() = default;
+  virtual ~MemoryOffline() = default;
+
+  bool Init(const std::string& file, uint64_t offset);
+
+  bool Read(uint64_t addr, void* dst, size_t size) override;
+
+ private:
+  uint64_t start_;
+};
+
+class MemoryRemote : public Memory {
+ public:
+  MemoryRemote(pid_t pid) : pid_(pid) {}
+  virtual ~MemoryRemote() = default;
+
+  bool Read(uint64_t addr, void* dst, size_t size) override;
+
+  pid_t pid() { return pid_; }
+
+ private:
+  pid_t pid_;
+};
+
+class MemoryLocal : public Memory {
+ public:
+  MemoryLocal() = default;
+  virtual ~MemoryLocal() = default;
+
+  bool Read(uint64_t addr, void* dst, size_t size) override;
+};
+
+class MemoryRange : public Memory {
+ public:
+  MemoryRange(Memory* memory, uint64_t begin, uint64_t end)
+      : memory_(memory), begin_(begin), length_(end - begin_) {}
+  virtual ~MemoryRange() { delete memory_; }
+
+  inline bool Read(uint64_t addr, void* dst, size_t size) override {
+    if (addr + size <= length_) {
+      return memory_->Read(addr + begin_, dst, size);
+    }
+    return false;
+  }
+
+ private:
+  Memory* memory_;
+  uint64_t begin_;
+  uint64_t length_;
+};
+
+#endif  // _LIBUNWINDSTACK_MEMORY_H