Port Android relocation packer to chromium build

third_party/android_platform/bionic/tools/relocation_packer/src/leb128.cc

 // Copyright 2014 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 "leb128.h"
 
 #include <stdint.h>
 #include <vector>
 
 #include "elf_traits.h"
 
 namespace relocation_packer {
 
 // Empty constructor and destructor to silence chromium-style.
-Leb128Encoder::Leb128Encoder() { }
-Leb128Encoder::~Leb128Encoder() { }
+template <typename uint_t>
+Leb128Encoder<uint_t>::Leb128Encoder() { }
+
+template <typename uint_t>
+Leb128Encoder<uint_t>::~Leb128Encoder() { }
 
 // Add a single value to the encoding.  Values are encoded with variable
 // length.  The least significant 7 bits of each byte hold 7 bits of data,
 // and the most significant bit is set on each byte except the last.
-void Leb128Encoder::Enqueue(ELF::Xword value) {
+template <typename uint_t>
+void Leb128Encoder<uint_t>::Enqueue(uint_t value) {
+  uint_t uvalue = static_cast<uint_t>(value);
   do {
-    const uint8_t byte = value & 127;
-    value >>= 7;
-    encoding_.push_back((value ? 128 : 0) | byte);
-  } while (value);
+    const uint8_t byte = uvalue & 127;
+    uvalue >>= 7;
+    encoding_.push_back((uvalue ? 128 : 0) | byte);
+  } while (uvalue);
 }
 
 // Add a vector of values to the encoding.
-void Leb128Encoder::EnqueueAll(const std::vector<ELF::Xword>& values) {
-  for (size_t i = 0; i < values.size(); ++i)
+template <typename uint_t>
+void Leb128Encoder<uint_t>::EnqueueAll(const std::vector<uint_t>& values) {
+  for (size_t i = 0; i < values.size(); ++i) {
     Enqueue(values[i]);
+  }
 }
 
 // Create a new decoder for the given encoded stream.
-Leb128Decoder::Leb128Decoder(const std::vector<uint8_t>& encoding) {
+template <typename uint_t>
+Leb128Decoder<uint_t>::Leb128Decoder(const std::vector<uint8_t>& encoding, size_t start_with) {
   encoding_ = encoding;
-  cursor_ = 0;
+  cursor_ = start_with;
 }
 
 // Empty destructor to silence chromium-style.
-Leb128Decoder::~Leb128Decoder() { }
+template <typename uint_t>
+Leb128Decoder<uint_t>::~Leb128Decoder() { }
 
 // Decode and retrieve a single value from the encoding.  Read forwards until
 // a byte without its most significant bit is found, then read the 7 bit
 // fields of the bytes spanned to re-form the value.
-ELF::Xword Leb128Decoder::Dequeue() {
-  ELF::Xword value = 0;
+template <typename uint_t>
+uint_t Leb128Decoder<uint_t>::Dequeue() {
+  uint_t value = 0;
 
   size_t shift = 0;
   uint8_t byte;
 
   // Loop until we reach a byte with its high order bit clear.
   do {
     byte = encoding_[cursor_++];
-    value |= static_cast<ELF::Xword>(byte & 127) << shift;
+    value |= static_cast<uint_t>(byte & 127) << shift;
     shift += 7;
   } while (byte & 128);
 
   return value;
 }
 
 // Decode and retrieve all remaining values from the encoding.
-void Leb128Decoder::DequeueAll(std::vector<ELF::Xword>* values) {
-  while (cursor_ < encoding_.size())
+template <typename uint_t>
+void Leb128Decoder<uint_t>::DequeueAll(std::vector<uint_t>* values) {
+  while (cursor_ < encoding_.size()) {
     values->push_back(Dequeue());
+  }
 }
 
+template class Leb128Encoder<uint32_t>;
+template class Leb128Encoder<uint64_t>;
+
+template class Leb128Decoder<uint32_t>;
+template class Leb128Decoder<uint64_t>;
+
 }  // namespace relocation_packer