AU: Retry up to 3 times 30 seconds apart on HTTP response code 0.

update_attempter.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/update_attempter.h"
 
 // From 'man clock_gettime': feature test macro: _POSIX_C_SOURCE >= 199309L
 #ifndef _POSIX_C_SOURCE
 #define _POSIX_C_SOURCE 199309L
 #endif  // _POSIX_C_SOURCE
@@ skipping 144 matching lines @@
   }
   LOG_IF(INFO, !obeying_proxies_) << "To help ensure updates work, this update "
       "check we are ignoring the proxy settings and using "
       "direct connections.";
 
   DisableDeltaUpdateIfNeeded();
   CHECK(!processor_->IsRunning());
   processor_->set_delegate(this);
 
   // Actions:
+  LibcurlHttpFetcher* update_check_fetcher =
+      new LibcurlHttpFetcher(GetProxyResolver());
+  // If this is an automatic check, try harder to connect to the network. See
+  // comment in libcurl_http_fetcher.cc.
+  if (!obey_proxies) {
+    update_check_fetcher->set_no_network_max_retries(3);
+  }
   shared_ptr<OmahaRequestAction> update_check_action(
       new OmahaRequestAction(prefs_,
                              omaha_request_params_,
                              NULL,
-                             new LibcurlHttpFetcher(GetProxyResolver())));
+                             update_check_fetcher));  // passes ownership
   shared_ptr<OmahaResponseHandlerAction> response_handler_action(
       new OmahaResponseHandlerAction(prefs_));
   shared_ptr<FilesystemCopierAction> filesystem_copier_action(
       new FilesystemCopierAction(false));
   shared_ptr<FilesystemCopierAction> kernel_filesystem_copier_action(
       new FilesystemCopierAction(true));
   shared_ptr<OmahaRequestAction> download_started_action(
       new OmahaRequestAction(prefs_,
                              omaha_request_params_,
                              new OmahaEvent(
@@ skipping 376 matching lines @@
     if (resume_offset < response_handler_action_->install_plan().size) {
       ranges.push_back(make_pair(resume_offset, -1));
     }
   } else {
     ranges.push_back(make_pair(0, -1));
   }
   fetcher->set_ranges(ranges);
 }
 
 }  // namespace chromeos_update_engine