[Glacier] Add a status object to hold error and a message.

lib/glacier/status/status.h

@@ -0,0 +1,63 @@
+#pragma once
+
+#include "status/error.h"
+#include "string/string.h"
+
+namespace glcr {
+
+class Status {
+ public:
+  static Status Ok() { return {}; }
+  Status(ErrorCode code) : code_(code), message_() {}
+  Status(ErrorCode code, StringView message) : code_(code), message_(message) {}
+
+  explicit operator bool() { return ok(); }
+  bool ok() { return code_ == OK; }
+
+  ErrorCode code() { return code_; }
+  StringView message() { return message_; }
+
+ private:
+  ErrorCode code_;
+  String message_;
+
+  Status();
+};
+
+Status InvalidArgument(StringView message) {
+  return Status(INVALID_ARGUMENT, message);
+}
+
+Status NotFound(StringView message) { return Status(NOT_FOUND, message); }
+
+Status PermissionDenied(StringView message) {
+  return Status(PERMISSION_DENIED, message);
+}
+
+Status NullPtr(StringView message) { return Status(NULL_PTR, message); }
+
+Status Empty(StringView message) { return Status(EMPTY, message); }
+
+Status AlreadyExists(StringView message) {
+  return Status(ALREADY_EXISTS, message);
+}
+
+Status BufferSize(StringView message) { return Status(BUFFER_SIZE, message); }
+
+Status FailedPrecondition(StringView message) {
+  return Status(FAILED_PRECONDITION, message);
+}
+
+Status Internal(StringView message) { return Status(INTERNAL, message); }
+
+Status Unimplemented(StringView message) {
+  return Status(UNIMPLEMENTED, message);
+}
+
+Status Exhausted(StringView message) { return Status(EXHAUSTED, message); }
+
+Status InvalidResponse(StringView message) {
+  return Status(INVALID_RESPONSE, message);
+}
+
+}  // namespace glcr