[Sync] Move //sync to //components/sync.

sync/internal_api/model_type_store_backend.cc

-// Copyright 2015 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 "sync/internal_api/public/model_type_store_backend.h"
-
-#include <utility>
-
-#include "base/files/file_path.h"
-#include "base/memory/ptr_util.h"
-#include "third_party/leveldatabase/env_chromium.h"
-#include "third_party/leveldatabase/src/helpers/memenv/memenv.h"
-#include "third_party/leveldatabase/src/include/leveldb/db.h"
-#include "third_party/leveldatabase/src/include/leveldb/env.h"
-#include "third_party/leveldatabase/src/include/leveldb/iterator.h"
-#include "third_party/leveldatabase/src/include/leveldb/options.h"
-#include "third_party/leveldatabase/src/include/leveldb/slice.h"
-#include "third_party/leveldatabase/src/include/leveldb/status.h"
-#include "third_party/leveldatabase/src/include/leveldb/write_batch.h"
-
-namespace syncer_v2 {
-
-// static
-base::LazyInstance<ModelTypeStoreBackend::BackendMap>
-    ModelTypeStoreBackend::backend_map_ = LAZY_INSTANCE_INITIALIZER;
-
-ModelTypeStoreBackend::ModelTypeStoreBackend(const std::string& path)
-    : path_(path) {}
-
-ModelTypeStoreBackend::~ModelTypeStoreBackend() {
-  backend_map_.Get().erase(path_);
-}
-
-std::unique_ptr<leveldb::Env> ModelTypeStoreBackend::CreateInMemoryEnv() {
-  return base::WrapUnique(leveldb::NewMemEnv(leveldb::Env::Default()));
-}
-
-// static
-scoped_refptr<ModelTypeStoreBackend> ModelTypeStoreBackend::GetOrCreateBackend(
-    const std::string& path,
-    std::unique_ptr<leveldb::Env> env,
-    ModelTypeStore::Result* result) {
-  if (backend_map_.Get().find(path) != backend_map_.Get().end()) {
-    *result = ModelTypeStore::Result::SUCCESS;
-    return make_scoped_refptr(backend_map_.Get()[path]);
-  }
-
-  scoped_refptr<ModelTypeStoreBackend> backend =
-      new ModelTypeStoreBackend(path);
-
-  *result = backend->Init(path, std::move(env));
-
-  if (*result == ModelTypeStore::Result::SUCCESS) {
-    backend_map_.Get()[path] = backend.get();
-  } else {
-    backend = nullptr;
-  }
-
-  return backend;
-}
-
-ModelTypeStore::Result ModelTypeStoreBackend::Init(
-    const std::string& path,
-    std::unique_ptr<leveldb::Env> env) {
-  DFAKE_SCOPED_LOCK(push_pop_);
-  leveldb::DB* db_raw = nullptr;
-
-  leveldb::Options options;
-  options.create_if_missing = true;
-  options.reuse_logs = leveldb_env::kDefaultLogReuseOptionValue;
-  options.paranoid_checks = true;
-  if (env.get()) {
-    options.env = env.get();
-    env_ = std::move(env);
-  }
-
-  leveldb::Status status = leveldb::DB::Open(options, path, &db_raw);
-  if (!status.ok()) {
-    DCHECK(db_raw == nullptr);
-    return ModelTypeStore::Result::UNSPECIFIED_ERROR;
-  }
-  db_.reset(db_raw);
-  return ModelTypeStore::Result::SUCCESS;
-}
-
-ModelTypeStore::Result ModelTypeStoreBackend::ReadRecordsWithPrefix(
-    const std::string& prefix,
-    const ModelTypeStore::IdList& id_list,
-    ModelTypeStore::RecordList* record_list,
-    ModelTypeStore::IdList* missing_id_list) {
-  DFAKE_SCOPED_LOCK(push_pop_);
-  DCHECK(db_);
-  record_list->reserve(id_list.size());
-  leveldb::ReadOptions read_options;
-  read_options.verify_checksums = true;
-  std::string key;
-  std::string value;
-  for (const std::string& id : id_list) {
-    key = prefix + id;
-    leveldb::Status status = db_->Get(read_options, key, &value);
-    if (status.ok()) {
-      // TODO(pavely): Use emplace_back instead of push_back once it is allowed.
-      record_list->push_back(ModelTypeStore::Record(id, value));
-    } else if (status.IsNotFound()) {
-      missing_id_list->push_back(id);
-    } else {
-      return ModelTypeStore::Result::UNSPECIFIED_ERROR;
-    }
-  }
-  return ModelTypeStore::Result::SUCCESS;
-}
-
-ModelTypeStore::Result ModelTypeStoreBackend::ReadAllRecordsWithPrefix(
-    const std::string& prefix,
-    ModelTypeStore::RecordList* record_list) {
-  DFAKE_SCOPED_LOCK(push_pop_);
-  DCHECK(db_);
-  leveldb::ReadOptions read_options;
-  read_options.verify_checksums = true;
-  std::unique_ptr<leveldb::Iterator> iter(db_->NewIterator(read_options));
-  const leveldb::Slice prefix_slice(prefix);
-  for (iter->Seek(prefix_slice); iter->Valid(); iter->Next()) {
-    leveldb::Slice key = iter->key();
-    if (!key.starts_with(prefix_slice))
-      break;
-    key.remove_prefix(prefix_slice.size());
-    // TODO(pavely): Use emplace_back instead of push_back once it is allowed.
-    record_list->push_back(
-        ModelTypeStore::Record(key.ToString(), iter->value().ToString()));
-  }
-  return iter->status().ok() ? ModelTypeStore::Result::SUCCESS
-                             : ModelTypeStore::Result::UNSPECIFIED_ERROR;
-}
-
-ModelTypeStore::Result ModelTypeStoreBackend::WriteModifications(
-    std::unique_ptr<leveldb::WriteBatch> write_batch) {
-  DFAKE_SCOPED_LOCK(push_pop_);
-  DCHECK(db_);
-  leveldb::Status status =
-      db_->Write(leveldb::WriteOptions(), write_batch.get());
-  return status.ok() ? ModelTypeStore::Result::SUCCESS
-                     : ModelTypeStore::Result::UNSPECIFIED_ERROR;
-}
-
-}  // namespace syncer_v2