AU: Try delta updates first, then full updates

src/platform/update_engine/main.cc

Index: src/platform/update_engine/main.cc
diff --git a/src/platform/update_engine/main.cc b/src/platform/update_engine/main.cc
index bbb6401e1db67b809167f60bdb90637a2725a019..bbd992767b9cc68886e506acf364ad0a3be1d295 100644
--- a/src/platform/update_engine/main.cc
+++ b/src/platform/update_engine/main.cc
@@ -2,12 +2,159 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+#include <string>
+#include <tr1/memory>
+#include <vector>
+#include <gflags/gflags.h>
 #include <glib.h>
+#include "chromeos/obsolete_logging.h"
+#include "update_engine/action_processor.h"
+#include "update_engine/download_action.h"
+#include "update_engine/filesystem_copier_action.h"
+#include "update_engine/install_action.h"
+#include "update_engine/libcurl_http_fetcher.h"
+#include "update_engine/omaha_request_prep_action.h"
+#include "update_engine/omaha_response_handler_action.h"
+#include "update_engine/postinstall_runner_action.h"
+#include "update_engine/set_bootable_flag_action.h"
+#include "update_engine/update_check_action.h"
+
+using std::string;
+using std::tr1::shared_ptr;
+using std::vector;
+
+namespace chromeos_update_engine {
+
+class UpdateAttempter : public ActionProcessorDelegate {
+ public:
+  UpdateAttempter(GMainLoop *loop)
+      : full_update_(false),
+        loop_(loop) {}
+  void Update(bool force_full_update);
+  
+  // Delegate method:
+  void ProcessingDone(const ActionProcessor* processor, bool success);
+ private:
+  bool full_update_;
+  vector<shared_ptr<AbstractAction> > actions_;
+  ActionProcessor processor_;
+  GMainLoop *loop_;
+
+  // pointer to the OmahaResponseHandlerAction in the actions_ vector;
+  shared_ptr<OmahaResponseHandlerAction> response_handler_action_;
+  DISALLOW_COPY_AND_ASSIGN(UpdateAttempter);
+};
+
+// Returns true on success. If there was no update available, that's still
+// success.
+// If force_full is true, try to force a full update.
+void UpdateAttempter::Update(bool force_full_update) {
+  full_update_ = force_full_update;
+  CHECK(!processor_.IsRunning());
+  processor_.set_delegate(this);
+
+  // Actions:
+  shared_ptr<OmahaRequestPrepAction> request_prep_action(
+      new OmahaRequestPrepAction(force_full_update));
+  shared_ptr<UpdateCheckAction> update_check_action(
+      new UpdateCheckAction(new LibcurlHttpFetcher));
+  shared_ptr<OmahaResponseHandlerAction> response_handler_action(
+      new OmahaResponseHandlerAction);
+  shared_ptr<FilesystemCopierAction> filesystem_copier_action(
+      new FilesystemCopierAction);
+  shared_ptr<DownloadAction> download_action(
+      new DownloadAction(new LibcurlHttpFetcher));
+  shared_ptr<InstallAction> install_action(
+      new InstallAction);
+  shared_ptr<PostinstallRunnerAction> postinstall_runner_action(
+      new PostinstallRunnerAction);
+  shared_ptr<SetBootableFlagAction> set_bootable_flag_action(
+      new SetBootableFlagAction);
+      
+  response_handler_action_ = response_handler_action;
+
+  actions_.push_back(shared_ptr<AbstractAction>(request_prep_action));
+  actions_.push_back(shared_ptr<AbstractAction>(update_check_action));
+  actions_.push_back(shared_ptr<AbstractAction>(response_handler_action));
+  actions_.push_back(shared_ptr<AbstractAction>(filesystem_copier_action));
+  actions_.push_back(shared_ptr<AbstractAction>(download_action));
+  actions_.push_back(shared_ptr<AbstractAction>(install_action));
+  actions_.push_back(shared_ptr<AbstractAction>(postinstall_runner_action));
+  actions_.push_back(shared_ptr<AbstractAction>(set_bootable_flag_action));
+  
+  // Enqueue the actions
+  for (vector<shared_ptr<AbstractAction> >::iterator it = actions_.begin();
+       it != actions_.end(); ++it) {
+    processor_.EnqueueAction(it->get());
+  }
+
+  // Bond them together. We have to use the leaf-types when calling
+  // BondActions().
+  BondActions(request_prep_action.get(), update_check_action.get());
+  BondActions(update_check_action.get(), response_handler_action.get());
+  BondActions(response_handler_action.get(), filesystem_copier_action.get());
+  BondActions(filesystem_copier_action.get(), download_action.get());
+  BondActions(download_action.get(), install_action.get());
+  BondActions(install_action.get(), postinstall_runner_action.get());
+  BondActions(postinstall_runner_action.get(), set_bootable_flag_action.get());
+
+  processor_.StartProcessing();
+}
+
+void UpdateAttempter::ProcessingDone(const ActionProcessor* processor,
+                                     bool success) {
+  CHECK(response_handler_action_);
+  if (response_handler_action_->GotNoUpdateResponse()) {
+    // All done.
+    g_main_loop_quit(loop_);
+    return;
+  }
+  if (!success) {
+    if (!full_update_) {
+      LOG(ERROR) << "Update failed. Attempting full update";
+      actions_.clear();
+      response_handler_action_.reset();
+      Update(true);
+      return;
+    } else {
+      LOG(ERROR) << "Full update failed. Aborting";
+    }
+  }
+  g_main_loop_quit(loop_);
+}
+
+gboolean UpdateInMainLoop(void* arg) {
+  UpdateAttempter* update_attempter = reinterpret_cast<UpdateAttempter*>(arg);
+  update_attempter->Update(false);
+  return FALSE;  // Don't call this callback function again
+}
+
+}  // namespace chromeos_update_engine
 
 #include "update_engine/subprocess.h"
 
 int main(int argc, char** argv) {
   g_thread_init(NULL);
   chromeos_update_engine::Subprocess::Init();
+  google::ParseCommandLineFlags(&argc, &argv, true);
+  // TODO(adlr): figure out log file
+  logging::InitLogging("",
+                       logging::LOG_ONLY_TO_SYSTEM_DEBUG_LOG,
+                       logging::DONT_LOCK_LOG_FILE,
+                       logging::APPEND_TO_OLD_LOG_FILE);
+  LOG(INFO) << "Chrome OS Update Engine starting";
+  
+  // Create the single GMainLoop
+  GMainLoop *loop = g_main_loop_new(g_main_context_default(), FALSE);
+
+  chromeos_update_engine::UpdateAttempter update_attempter(loop);
+
+  g_timeout_add(0, &chromeos_update_engine::UpdateInMainLoop,
+                &update_attempter);
+
+  g_main_loop_run(loop);
+  g_main_loop_unref(loop);
+
+  LOG(INFO) << "Chrome OS Update Engine terminating";
   return 0;
 }