AU: Implement getting of tracks through GetTrack.

omaha_request_params.cc

 // Copyright (c) 2010 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 "update_engine/omaha_request_params.h"
 
 #include <errno.h>
 #include <fcntl.h>
 #include <sys/utsname.h>
 
@@ skipping 74 matching lines @@
   app_track = track;
   return true;
 }
 
 bool OmahaRequestDeviceParams::SetDeviceTrack(const std::string& track) {
   OmahaRequestDeviceParams params;
   TEST_AND_RETURN_FALSE(params.Init("", ""));
   return params.SetTrack(track);
 }
 
+string OmahaRequestDeviceParams::GetDeviceTrack() {
+  OmahaRequestDeviceParams params;
+  // Note that params.app_track is an empty string if the value in
+  // lsb-release file is invalid. See Init() for details.
+  return params.Init("", "") ? params.app_track : "";
+}
+
 string OmahaRequestDeviceParams::GetLsbValue(const string& key,
                                              const string& default_value,
                                              ValueValidator validator) const {
   string files[] = {string(utils::kStatefulPartition) + "/etc/lsb-release",
                     "/etc/lsb-release"};
   for (unsigned int i = 0; i < arraysize(files); ++i) {
     // TODO(adlr): make sure files checked are owned as root (and all
     // their parents are recursively, too).
     string file_data;
     if (!utils::ReadFileToString(root_ + files[i], &file_data))
@@ skipping 38 matching lines @@
   return IsOfficialBuild() ?
       (track == "beta-channel" || track == "dev-channel") : true;
 }
 
 void OmahaRequestDeviceParams::SetBuildTypeOfficial(bool is_official) {
   force_build_type_ = true;
   forced_official_build_ = is_official;
 }
 
 }  // namespace chromeos_update_engine