Initial public release of nearby library

Signed-off-by: Alexey Polyudov <apolyudov@google.com>
Change-Id: I85d490e448375aa4eb7b09680757c02fff1420b4

cpp/platform/base64_utils.cc

@@ -0,0 +1,71 @@
+// Copyright 2020 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "platform/base64_utils.h"
+
+#include "absl/strings/escaping.h"
+
+namespace location {
+namespace nearby {
+
+std::string Base64Utils::encode(ConstPtr<ByteArray> bytes) {
+  std::string base64_string;
+
+  if (!bytes.isNull()) {
+    absl::WebSafeBase64Escape(bytes->asString(), &base64_string);
+  }
+
+  return base64_string;
+}
+
+std::string Base64Utils::encode(const ByteArray& bytes) {
+  std::string base64_string;
+  absl::WebSafeBase64Escape(bytes.asString(), &base64_string);
+
+  return base64_string;
+}
+
+std::string Base64Utils::encode(absl::string_view input) {
+  std::string base64_string;
+  absl::WebSafeBase64Escape(input, &base64_string);
+
+  return base64_string;
+}
+
+template<>
+Ptr<ByteArray> Base64Utils::decode(absl::string_view base64_string) {
+  std::string decoded_string;
+  if (!absl::WebSafeBase64Unescape(base64_string, &decoded_string)) {
+    return Ptr<ByteArray>();
+  }
+
+  return MakePtr(new ByteArray(decoded_string));
+}
+
+template<>
+ByteArray Base64Utils::decode(absl::string_view base64_string) {
+  std::string decoded_string;
+  if (!absl::WebSafeBase64Unescape(base64_string, &decoded_string)) {
+    return ByteArray();
+  }
+
+  return ByteArray(decoded_string);
+}
+
+Ptr<ByteArray> Base64Utils::decode(absl::string_view base64_string) {
+  return decode<Ptr<ByteArray>>(base64_string);
+}
+
+}  // namespace nearby
+}  // namespace location