From fec4d2cc3f5c1d98b616d6d9a6bc309bebb3783c Mon Sep 17 00:00:00 2001
From: Bertrand SIMONNET <bsimonnet@google.com>
Date: Wed, 5 Aug 2015 16:04:14 -0700
Subject: [PATCH] metrics: Add a CLI flag to disable dbus.

DBus is not setup in several targets and the metrics_daemon will crash
if it cannot connect to DBus.
Running metrics daemon without dbus allows us to test the daemon in any
target.

BUG: 22879597

Change-Id: Ica69c8e96c3df794a210a0fa3d44f85a98a660f0
---
 metrics/metrics_daemon.cc      | 45 +++++++++++++++++++---------------
 metrics/metrics_daemon.h       |  5 ++++
 metrics/metrics_daemon_main.cc |  4 +++
 3 files changed, 34 insertions(+), 20 deletions(-)

diff --git a/metrics/metrics_daemon.cc b/metrics/metrics_daemon.cc
index 634027842..f9061d563 100644
--- a/metrics/metrics_daemon.cc
+++ b/metrics/metrics_daemon.cc
@@ -210,6 +210,7 @@ uint32_t MetricsDaemon::GetOsVersionHash() {
 
 void MetricsDaemon::Init(bool testing,
                          bool uploader_active,
+                         bool dbus_enabled,
                          MetricsLibraryInterface* metrics_lib,
                          const string& vmstats_path,
                          const string& scaling_max_freq_path,
@@ -220,6 +221,7 @@ void MetricsDaemon::Init(bool testing,
                          const string& config_root) {
   testing_ = testing;
   uploader_active_ = uploader_active;
+  dbus_enabled_ = dbus_enabled;
   config_root_ = config_root;
   DCHECK(metrics_lib != nullptr);
   metrics_lib_ = metrics_lib;
@@ -275,36 +277,39 @@ void MetricsDaemon::Init(bool testing,
 }
 
 int MetricsDaemon::OnInit() {
-  int return_code = chromeos::DBusDaemon::OnInit();
+  int return_code = dbus_enabled_ ? chromeos::DBusDaemon::OnInit() :
+      chromeos::Daemon::OnInit();
   if (return_code != EX_OK)
     return return_code;
 
   if (testing_)
     return EX_OK;
 
-  bus_->AssertOnDBusThread();
-  CHECK(bus_->SetUpAsyncOperations());
+  if (dbus_enabled_) {
+    bus_->AssertOnDBusThread();
+    CHECK(bus_->SetUpAsyncOperations());
 
-  if (bus_->is_connected()) {
-    const std::string match_rule =
-        base::StringPrintf(kCrashReporterMatchRule,
-                           kCrashReporterInterface,
-                           kCrashReporterUserCrashSignal);
+    if (bus_->is_connected()) {
+      const std::string match_rule =
+          base::StringPrintf(kCrashReporterMatchRule,
+                             kCrashReporterInterface,
+                             kCrashReporterUserCrashSignal);
 
-    bus_->AddFilterFunction(&MetricsDaemon::MessageFilter, this);
+      bus_->AddFilterFunction(&MetricsDaemon::MessageFilter, this);
 
-    DBusError error;
-    dbus_error_init(&error);
-    bus_->AddMatch(match_rule, &error);
+      DBusError error;
+      dbus_error_init(&error);
+      bus_->AddMatch(match_rule, &error);
 
-    if (dbus_error_is_set(&error)) {
-      LOG(ERROR) << "Failed to add match rule \"" << match_rule << "\". Got "
-          << error.name << ": " << error.message;
-      return EX_SOFTWARE;
+      if (dbus_error_is_set(&error)) {
+        LOG(ERROR) << "Failed to add match rule \"" << match_rule << "\". Got "
+            << error.name << ": " << error.message;
+        return EX_SOFTWARE;
+      }
+    } else {
+      LOG(ERROR) << "DBus isn't connected.";
+      return EX_UNAVAILABLE;
     }
-  } else {
-    LOG(ERROR) << "DBus isn't connected.";
-    return EX_UNAVAILABLE;
   }
 
   if (uploader_active_) {
@@ -317,7 +322,7 @@ int MetricsDaemon::OnInit() {
 }
 
 void MetricsDaemon::OnShutdown(int* return_code) {
-  if (!testing_ && bus_->is_connected()) {
+  if (!testing_ && dbus_enabled_ && bus_->is_connected()) {
     const std::string match_rule =
         base::StringPrintf(kCrashReporterMatchRule,
                            kCrashReporterInterface,
diff --git a/metrics/metrics_daemon.h b/metrics/metrics_daemon.h
index 49e6d7058..ccac52a19 100644
--- a/metrics/metrics_daemon.h
+++ b/metrics/metrics_daemon.h
@@ -31,6 +31,7 @@ class MetricsDaemon : public chromeos::DBusDaemon {
   // Initializes metrics class variables.
   void Init(bool testing,
             bool uploader_active,
+            bool dbus_enabled,
             MetricsLibraryInterface* metrics_lib,
             const std::string& vmstats_path,
             const std::string& cpuinfo_max_freq_path,
@@ -289,6 +290,10 @@ class MetricsDaemon : public chromeos::DBusDaemon {
   // Whether the uploader is enabled or disabled.
   bool uploader_active_;
 
+  // Whether or not dbus should be used.
+  // If disabled, we will not collect the frequency of crashes.
+  bool dbus_enabled_;
+
   // Root of the configuration files to use.
   std::string config_root_;
 
diff --git a/metrics/metrics_daemon_main.cc b/metrics/metrics_daemon_main.cc
index 01a6f7bd0..6c580ba25 100644
--- a/metrics/metrics_daemon_main.cc
+++ b/metrics/metrics_daemon_main.cc
@@ -29,6 +29,9 @@ int main(int argc, char** argv) {
               false,
               "run the uploader once and exit");
 
+  // Enable dbus.
+  DEFINE_bool(withdbus, true, "Enable dbus");
+
   // Upload Service flags.
   DEFINE_int32(upload_interval_secs,
                1800,
@@ -58,6 +61,7 @@ int main(int argc, char** argv) {
   MetricsDaemon daemon;
   daemon.Init(FLAGS_uploader_test,
               FLAGS_uploader | FLAGS_uploader_test,
+              FLAGS_withdbus,
               &metrics_lib,
               "/proc/vmstat",
               kScalingMaxFreqPath,