diff --git a/libs/androidfw/BigBuffer.cpp b/libs/androidfw/BigBuffer.cpp
new file mode 100644
index 0000000..bedfc49
--- /dev/null
+++ b/libs/androidfw/BigBuffer.cpp
@@ -0,0 +1,87 @@
+/*
+ * 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 <androidfw/BigBuffer.h>
+
+#include <algorithm>
+#include <memory>
+#include <vector>
+
+#include "android-base/logging.h"
+
+namespace android {
+
+void* BigBuffer::NextBlockImpl(size_t size) {
+  if (!blocks_.empty()) {
+    Block& block = blocks_.back();
+    if (block.block_size_ - block.size >= size) {
+      void* out_buffer = block.buffer.get() + block.size;
+      block.size += size;
+      size_ += size;
+      return out_buffer;
+    }
+  }
+
+  const size_t actual_size = std::max(block_size_, size);
+
+  Block block = {};
+
+  // Zero-allocate the block's buffer.
+  block.buffer = std::unique_ptr<uint8_t[]>(new uint8_t[actual_size]());
+  CHECK(block.buffer);
+
+  block.size = size;
+  block.block_size_ = actual_size;
+
+  blocks_.push_back(std::move(block));
+  size_ += size;
+  return blocks_.back().buffer.get();
+}
+
+void* BigBuffer::NextBlock(size_t* out_size) {
+  if (!blocks_.empty()) {
+    Block& block = blocks_.back();
+    if (block.size != block.block_size_) {
+      void* out_buffer = block.buffer.get() + block.size;
+      size_t size = block.block_size_ - block.size;
+      block.size = block.block_size_;
+      size_ += size;
+      *out_size = size;
+      return out_buffer;
+    }
+  }
+
+  // Zero-allocate the block's buffer.
+  Block block = {};
+  block.buffer = std::unique_ptr<uint8_t[]>(new uint8_t[block_size_]());
+  CHECK(block.buffer);
+  block.size = block_size_;
+  block.block_size_ = block_size_;
+  blocks_.push_back(std::move(block));
+  size_ += block_size_;
+  *out_size = block_size_;
+  return blocks_.back().buffer.get();
+}
+
+std::string BigBuffer::to_string() const {
+  std::string result;
+  for (const Block& block : blocks_) {
+    result.append(block.buffer.get(), block.buffer.get() + block.size);
+  }
+  return result;
+}
+
+}  // namespace android