mojo leveldb: Add an iteration interface.

components/leveldb/public/cpp/util.cc

+// Copyright 2016 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 "components/leveldb/public/cpp/util.h"
+
+#include "third_party/leveldatabase/src/include/leveldb/status.h"
+
+namespace leveldb {
+
+DatabaseError LeveldbStatusToError(const leveldb::Status& s) {
+  if (s.ok())
+    return DatabaseError::OK;
+  if (s.IsNotFound())
+    return DatabaseError::NOT_FOUND;
+  if (s.IsCorruption())
+    return DatabaseError::CORRUPTION;
+  if (s.IsNotSupportedError())
+    return DatabaseError::NOT_SUPPORTED;
+  if (s.IsIOError())
+    return DatabaseError::IO_ERROR;
+  return DatabaseError::INVALID_ARGUMENT;
+}
+
+leveldb::Status DatabaseErrorToStatus(DatabaseError e,
+                                      const Slice& msg,
+                                      const Slice& msg2) {
+  switch (e) {
+    case DatabaseError::OK:
+      return leveldb::Status::OK();
+    case DatabaseError::NOT_FOUND:
+      return leveldb::Status::NotFound(msg, msg2);
+    case DatabaseError::CORRUPTION:
+      return leveldb::Status::Corruption(msg, msg2);
+    case DatabaseError::NOT_SUPPORTED:
+      return leveldb::Status::NotSupported(msg, msg2);
+    case DatabaseError::INVALID_ARGUMENT:
+      return leveldb::Status::InvalidArgument(msg, msg2);
+    case DatabaseError::IO_ERROR:
+      return leveldb::Status::IOError(msg, msg2);
+  }
+
+  // This will never be reached, but we still have configurations which don't
+  // do switch enum checking.
+  return leveldb::Status::InvalidArgument(msg, msg2);
+}
+
+leveldb::Slice GetSliceFor(const mojo::Array<uint8_t>& key) {
+  if (key.size() == 0)
+    return leveldb::Slice();
+  return leveldb::Slice(reinterpret_cast<const char*>(&key.front()),
+                        key.size());
+}
+
+mojo::Array<uint8_t> GetArrayFor(const leveldb::Slice& s) {
+  if (s.size() == 0)
+    return mojo::Array<uint8_t>();
+  return mojo::Array<uint8_t>(std::vector<uint8_t>(
+      reinterpret_cast<const uint8_t*>(s.data()),
+      reinterpret_cast<const uint8_t*>(s.data() + s.size())));
+}
+
+}  // namespace leveldb