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#ifndef NET_DISK_CACHE_CACHE_INTERNAL_INL_H__
#define NET_DISK_CACHE_CACHE_INTERNAL_INL_H__

#include "net/disk_cache/storage_block.h"

#include "net/disk_cache/trace.h"

namespace disk_cache {

template<typename T> StorageBlock<T>::StorageBlock(MappedFile* file,
                                                   Addr address)
    : file_(file), address_(address), data_(NULL), modified_(false),
      own_data_(false), extended_(false) {
  if (address.num_blocks() > 1)
    extended_ = true;
  DCHECK(!address.is_initialized() || sizeof(*data_) == address.BlockSize());
}

template<typename T> StorageBlock<T>::~StorageBlock() {
  if (modified_)
    Store();
  if (own_data_)
    delete data_;
}

template<typename T> void* StorageBlock<T>::buffer() const {
  return data_;
}

template<typename T> size_t StorageBlock<T>::size() const {
  if (!extended_)
    return sizeof(*data_);
  return address_.num_blocks() * sizeof(*data_);
}

template<typename T> int StorageBlock<T>::offset() const {
  return address_.start_block() * address_.BlockSize();
}

template<typename T> bool StorageBlock<T>::LazyInit(MappedFile* file,
                                                    Addr address) {
  if (file_ || address_.is_initialized()) {
    NOTREACHED();
    return false;
  }
  file_ = file;
  address_.set_value(address.value());
  if (address.num_blocks() > 1)
    extended_ = true;

  DCHECK(sizeof(*data_) == address.BlockSize());
  return true;
}

template<typename T> void StorageBlock<T>::SetData(T* other) {
  DCHECK(!modified_);
  if (own_data_) {
    delete data_;
    own_data_ = false;
  }
  data_ = other;
}

template<typename T> void StorageBlock<T>::set_modified() {
  DCHECK(data_);
  modified_ = true;
}

template<typename T> T* StorageBlock<T>::Data() {
  if (!data_)
    AllocateData();
  return data_;
}

template<typename T> bool StorageBlock<T>::HasData() const {
  return (NULL != data_);
}

template<typename T> const Addr StorageBlock<T>::address() const {
  return address_;
}

template<typename T> bool StorageBlock<T>::Load() {
  if (file_) {
    if (!data_)
      AllocateData();

    if (file_->Load(this)) {
      modified_ = false;
      return true;
    }
  }
  LOG(WARNING) << "Failed data load.";
  Trace("Failed data load.");
  return false;
}

template<typename T> bool StorageBlock<T>::Store() {
  if (file_) {
    if (file_->Store(this)) {
      modified_ = false;
      return true;
    }
  }
  LOG(ERROR) << "Failed data store.";
  Trace("Failed data store.");
  return false;
}

template<typename T> void StorageBlock<T>::AllocateData() {
  DCHECK(!data_);
  if (!extended_) {
    data_ = new T;
  } else {
    void* buffer = new char[address_.num_blocks() * sizeof(*data_)];
    data_ = new(buffer) T;
  }
  own_data_ = true;
}

}  // namespace disk_cache

#endif  // NET_DISK_CACHE_CACHE_INTERNAL_INL_H__