Isolates generic DnsClient from AsyncHostResolver.

net/base/bigendian.cc

+// Copyright (c) 2011 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 "net/base/bigendian.h"
+
+namespace net {
+
+BigEndianReader::BigEndianReader(const void* buf, size_t len)
+    : ptr_(reinterpret_cast<const char*>(buf)), end_(ptr_ + len) {}
+
+bool BigEndianReader::Skip(size_t len) {
+  if (ptr_ + len > end_)
+    return false;
+  ptr_+= len;
+  return true;
+}
+
+bool BigEndianReader::Copy(void* out, size_t len) {
+  if (ptr_ + len > end_)
+    return false;
+  memcpy(out, ptr_, len);
+  ptr_+= len;
+  return true;
+}
+
+bool BigEndianReader::Piece(base::StringPiece* out, size_t len) {
+  if (ptr_ + len > end_)
+    return false;
+  *out = base::StringPiece(ptr_, len);
+  ptr_+= len;
+  return true;
+}
+
+template<typename T>
+bool BigEndianReader::Read(T* v) {
+  if (ptr_ + sizeof(T) > end_)
+    return false;
+  ReadBigEndian<T>(ptr_, v);
+  ptr_+= sizeof(T);
+  return true;
+}
+
+bool BigEndianReader::U8(uint8* v) {
+  return Read(v);
+}
+
+bool BigEndianReader::U16(uint16* v) {
+  return Read(v);
+}
+
+bool BigEndianReader::U32(uint32* v) {
+  return Read(v);
+}
+
+BigEndianWriter::BigEndianWriter(void* buf, size_t len)
+    : ptr_(reinterpret_cast<char*>(buf)), end_(ptr_ + len) {}
+
+bool BigEndianWriter::Skip(size_t len) {
+  if (ptr_ + len > end_)
+    return false;
+  ptr_+= len;
+  return true;
+}
+
+bool BigEndianWriter::Copy(const void* buf, size_t len) {
+  if (ptr_ + len > end_)
+    return false;
+  memcpy(ptr_, buf, len);
+  ptr_+= len;
+  return true;
+}
+
+template<typename T>
+bool BigEndianWriter::Write(T v) {
+  if (ptr_ + sizeof(T) > end_)
+    return false;
+  WriteBigEndian<T>(ptr_, v);
+  ptr_+= sizeof(T);
+  return true;
+}
+
+bool BigEndianWriter::U8(uint8 v) {
+  return Write(v);
+}
+
+bool BigEndianWriter::U16(uint16 v) {
+  return Write(v);
+}
+
+bool BigEndianWriter::U32(uint32 v) {
+  return Write(v);
+}
+
+}  // namespace net
+