1 files changed, 95 insertions, 0 deletions
diff --git a/brillo/dbus/utils.cc b/brillo/dbus/utils.cc
new file mode 100644
index 0000000..4fbd0ef
--- /dev/null
+++ b/brillo/dbus/utils.cc
@@ -0,0 +1,95 @@
+// Copyright 2014 The Chromium OS 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 <brillo/dbus/utils.h>
+
+#include <tuple>
+#include <vector>
+
+#include <base/bind.h>
+#include <base/memory/scoped_ptr.h>
+#include <brillo/errors/error_codes.h>
+#include <brillo/strings/string_utils.h>
+
+namespace brillo {
+namespace dbus_utils {
+
+std::unique_ptr<dbus::Response> CreateDBusErrorResponse(
+    dbus::MethodCall* method_call,
+    const std::string& error_name,
+    const std::string& error_message) {
+  auto resp = dbus::ErrorResponse::FromMethodCall(
+      method_call, error_name, error_message);
+  return std::unique_ptr<dbus::Response>(resp.release());
+}
+
+std::unique_ptr<dbus::Response> GetDBusError(dbus::MethodCall* method_call,
+                                             const brillo::Error* error) {
+  CHECK(error) << "Error object must be specified";
+  std::string error_name = DBUS_ERROR_FAILED;  // Default error code.
+  std::string error_message;
+
+  // Special case for "dbus" error domain.
+  // Pop the error code and message from the error chain and use them as the
+  // actual D-Bus error message.
+  if (error->GetDomain() == errors::dbus::kDomain) {
+    error_name = error->GetCode();
+    error_message = error->GetMessage();
+    error = error->GetInnerError();
+  }
+
+  // Append any inner errors to the error message.
+  while (error) {
+    // Format error string as "domain/code:message".
+    if (!error_message.empty())
+      error_message += ';';
+    error_message +=
+        error->GetDomain() + '/' + error->GetCode() + ':' + error->GetMessage();
+    error = error->GetInnerError();
+  }
+  return CreateDBusErrorResponse(method_call, error_name, error_message);
+}
+
+void AddDBusError(brillo::ErrorPtr* error,
+                  const std::string& dbus_error_name,
+                  const std::string& dbus_error_message) {
+  std::vector<std::string> parts = string_utils::Split(dbus_error_message, ";");
+  std::vector<std::tuple<std::string, std::string, std::string>> errors;
+  for (const std::string& part : parts) {
+    // Each part should be in format of "domain/code:message"
+    size_t slash_pos = part.find('/');
+    size_t colon_pos = part.find(':');
+    if (slash_pos != std::string::npos && colon_pos != std::string::npos &&
+        slash_pos < colon_pos) {
+      // If we have both '/' and ':' and in proper order, then we have a
+      // correctly encoded error object.
+      std::string domain = part.substr(0, slash_pos);
+      std::string code = part.substr(slash_pos + 1, colon_pos - slash_pos - 1);
+      std::string message = part.substr(colon_pos + 1);
+      errors.emplace_back(domain, code, message);
+    } else if (slash_pos == std::string::npos &&
+               colon_pos == std::string::npos && errors.empty()) {
+      // If we don't have both '/' and ':' and this is the first error object,
+      // then we had a D-Bus error at the top of the error chain.
+      errors.emplace_back(errors::dbus::kDomain, dbus_error_name, part);
+    } else {
+      // We have a malformed part. The whole D-Bus error was most likely
+      // not generated by GetDBusError(). To be safe, stop parsing it
+      // and return the error as received from D-Bus.
+      errors.clear();  // Remove any errors accumulated so far.
+      errors.emplace_back(
+          errors::dbus::kDomain, dbus_error_name, dbus_error_message);
+      break;
+    }
+  }
+
+  // Go backwards and add the parsed errors to the error chain.
+  for (auto it = errors.crbegin(); it != errors.crend(); ++it) {
+    Error::AddTo(
+        error, FROM_HERE, std::get<0>(*it), std::get<1>(*it), std::get<2>(*it));
+  }
+}
+
+}  // namespace dbus_utils
+}  // namespace brillo