commit cc169259cd4451d6bf23c04ed07ac69a1d4d9444
author Alex Deymo <deymo@chromium.org> Wed Jun 10 19:10:14 2015 -0700
committer ChromeOS Commit Bot <chromeos-commit-bot@chromium.org> Sat Jun 13 02:53:19 2015 +0000
tree b24bd75d69f118c204a36ff1c81558b27b4c11fd
parent a50870549b0fc16b659250449fffbd3eacc57d8b

update_engine: Switch main to GlibMessageLoop.

This patch instanciates a GlibMessageLoop for the main thread that
can be used by any module by calling MessageLoop::current().

BUG=brillo:91
TEST=Ran update_engine on a link device. Main loop still works.

Change-Id: I42a6011515de77a77dfb636cc5ae9488e072ad58
Reviewed-on: https://chromium-review.googlesource.com/276891
Reviewed-by: Gilad Arnold <garnold@chromium.org>
Commit-Queue: Alex Deymo <deymo@chromium.org>
Tested-by: Alex Deymo <deymo@chromium.org>

main.cc

diff --git a/main.cc b/main.cc
index 0fbfdaa..159c88f 100644
--- a/main.cc
+++ b/main.cc
@@ -15,6 +15,7 @@
 #include <base/strings/stringprintf.h>
 #include <base/time/time.h>
 #include <chromeos/flag_helper.h>
+#include <chromeos/message_loops/glib_message_loop.h>
 #include <glib.h>
 #include <metrics/metrics_library.h>
 #include <sys/stat.h>
@@ -43,21 +44,6 @@
 
 namespace chromeos_update_engine {
 
-gboolean UpdateBootFlags(void* arg) {
-  reinterpret_cast<UpdateAttempter*>(arg)->UpdateBootFlags();
-  return FALSE;  // Don't call this callback again
-}
-
-gboolean BroadcastStatus(void* arg) {
-  reinterpret_cast<UpdateAttempter*>(arg)->BroadcastStatus();
-  return FALSE;  // Don't call this callback again
-}
-
-gboolean UpdateEngineStarted(gpointer user_data) {
-  reinterpret_cast<UpdateAttempter*>(user_data)->UpdateEngineStarted();
-  return FALSE;  // Remove idle source (e.g. don't do the callback again)
-}
-
 namespace {
 
 // Wait for DBus to be ready by attempting to get the system bus up to
@@ -197,8 +183,13 @@
   // Done _after_ log file creation.
   umask(S_IXUSR | S_IRWXG | S_IRWXO);
 
-  // Create the single GMainLoop
-  GMainLoop* loop = g_main_loop_new(g_main_context_default(), FALSE);
+  // Create the single Glib main loop. Code accessing directly the glib main
+  // loop (such as calling g_timeout_add() or similar functions) will still work
+  // since the backend for the message loop is still the Glib main loop.
+  // TODO(deymo): Replace this |loop| with one based on libevent once no other
+  // code here uses glib directly.
+  chromeos::GlibMessageLoop loop;
+  loop.SetAsCurrent();
 
   // Wait up to 2 minutes for DBus to be ready.
   LOG_IF(FATAL, !chromeos_update_engine::WaitForDBusSystem(
@@ -231,25 +222,30 @@
   update_attempter->ScheduleUpdates();
 
   // Update boot flags after 45 seconds.
-  g_timeout_add_seconds(45,
-                        &chromeos_update_engine::UpdateBootFlags,
-                        update_attempter);
+  loop.PostDelayedTask(
+      base::Bind(&chromeos_update_engine::UpdateAttempter::UpdateBootFlags,
+                 base::Unretained(update_attempter)),
+      base::TimeDelta::FromSeconds(45));
 
   // Broadcast the update engine status on startup to ensure consistent system
   // state on crashes.
-  g_idle_add(&chromeos_update_engine::BroadcastStatus, update_attempter);
+  loop.PostTask(base::Bind(
+      &chromeos_update_engine::UpdateAttempter::BroadcastStatus,
+      base::Unretained(update_attempter)));
 
   // Run the UpdateEngineStarted() method on |update_attempter|.
-  g_idle_add(&chromeos_update_engine::UpdateEngineStarted, update_attempter);
+  loop.PostTask(base::Bind(
+      &chromeos_update_engine::UpdateAttempter::UpdateEngineStarted,
+      base::Unretained(update_attempter)));
 
   // Run the main loop until exit time:
-  g_main_loop_run(loop);
+  loop.Run();
 
   // Cleanup:
-  g_main_loop_unref(loop);
   update_attempter->set_dbus_service(nullptr);
   g_object_unref(G_OBJECT(service));
 
+  loop.ReleaseFromCurrent();
   LOG(INFO) << "Chrome OS Update Engine terminating";
   return 0;
 }