accelerometer: USE USE_IIOSERVICE build flag

BUG=b:168434557
TEST=unit tests

Change-Id: I896495d19cc5c8ebdc3a696e537b18302644d389
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2624128
Commit-Queue: Cheng-Hao Yang <chenghaoyang@chromium.org>
Reviewed-by: Xiaoqian Dai <xdai@chromium.org>
Cr-Commit-Position: refs/heads/master@{#843415}

ash/BUILD.gn

@@ -6,6 +6,7 @@ import("//build/config/features.gni")
 import("//build/config/python.gni")
 import("//build/config/ui.gni")
 import("//chromeos/assistant/ambient.gni")
+import("//chromeos/components/sensors/buildflags.gni")
 import("//mojo/public/tools/bindings/mojom.gni")
 import("//testing/test.gni")
 import("//tools/grit/repack.gni")
@@ -132,12 +133,8 @@ component("ash") {
     "accelerometer/accelerometer_constants.h",
     "accelerometer/accelerometer_file_reader.cc",
     "accelerometer/accelerometer_file_reader.h",
-    "accelerometer/accelerometer_provider_mojo.cc",
-    "accelerometer/accelerometer_provider_mojo.h",
     "accelerometer/accelerometer_reader.cc",
     "accelerometer/accelerometer_reader.h",
-    "accelerometer/accelerometer_samples_observer.cc",
-    "accelerometer/accelerometer_samples_observer.h",
     "accelerometer/accelerometer_types.cc",
     "accelerometer/accelerometer_types.h",
     "accessibility/accessibility_controller_impl.cc",
@@ -1795,8 +1792,7 @@ component("ash") {
     # TODO(https://crbug.com/644336): Make CrasAudioHandler Chrome or Ash only.
     "//chromeos/audio",
     "//chromeos/components/multidevice/logging",
-    "//chromeos/components/sensors:sensors",
-    "//chromeos/components/sensors/mojom",
+    "//chromeos/components/sensors:buildflags",
     "//chromeos/constants",
     "//chromeos/dbus",
 
@@ -1924,6 +1920,23 @@ component("ash") {
       "//chromeos/assistant/internal/proto/google3",
     ]
   }
+
+  if (use_iioservice) {
+    sources -= [
+      "accelerometer/accelerometer_file_reader.cc",
+      "accelerometer/accelerometer_file_reader.h",
+    ]
+    sources += [
+      "accelerometer/accelerometer_provider_mojo.cc",
+      "accelerometer/accelerometer_provider_mojo.h",
+      "accelerometer/accelerometer_samples_observer.cc",
+      "accelerometer/accelerometer_samples_observer.h",
+    ]
+    deps += [
+      "//chromeos/components/sensors:sensors",
+      "//chromeos/components/sensors/mojom",
+    ]
+  }
 }
 
 # TODO(crbug.com/1112471): Get this to run cleanly under Python 3.
@@ -1954,8 +1967,6 @@ test("ash_unittests") {
     "accelerators/accelerator_unittest.cc",
     "accelerators/magnifier_key_scroller_unittest.cc",
     "accelerators/spoken_feedback_toggler_unittest.cc",
-    "accelerometer/accelerometer_provider_mojo_unittest.cc",
-    "accelerometer/accelerometer_samples_observer_unittest.cc",
     "accessibility/accessibility_controller_unittest.cc",
     "accessibility/accessibility_focus_ring_controller_unittest.cc",
     "accessibility/accessibility_focus_ring_group_unittest.cc",
@@ -2405,9 +2416,6 @@ test("ash_unittests") {
     "//chromeos/audio",
     "//chromeos/components/phonehub:test_support",
     "//chromeos/components/quick_answers:quick_answers",
-    "//chromeos/components/sensors:sensors",
-    "//chromeos/components/sensors:test_support",
-    "//chromeos/components/sensors/mojom",
     "//chromeos/constants",
     "//chromeos/dbus:test_support",
     "//chromeos/dbus/audio",
@@ -2513,6 +2521,18 @@ test("ash_unittests") {
     "//content/public/browser",
     "//content/public/common",
   ]
+
+  if (use_iioservice) {
+    sources += [
+      "accelerometer/accelerometer_provider_mojo_unittest.cc",
+      "accelerometer/accelerometer_samples_observer_unittest.cc",
+    ]
+    deps += [
+      "//chromeos/components/sensors:sensors",
+      "//chromeos/components/sensors:test_support",
+      "//chromeos/components/sensors/mojom",
+    ]
+  }
 }
 
 # TODO(oshima): Remove or migrate to new ash_ui_perftests

ash/accelerometer/accelerometer_provider_mojo.cc

@@ -94,8 +94,13 @@ AccelerometerProviderMojo::~AccelerometerProviderMojo() = default;
 void AccelerometerProviderMojo::RegisterSensorClient() {
   DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
 
-  chromeos::sensors::SensorHalDispatcher::GetInstance()->RegisterClient(
-      sensor_hal_client_.BindNewPipeAndPassRemote());
+  auto* dispatcher = chromeos::sensors::SensorHalDispatcher::GetInstance();
+  if (!dispatcher) {
+    // In unit tests, SensorHalDispatcher is not initialized.
+    return;
+  }
+
+  dispatcher->RegisterClient(sensor_hal_client_.BindNewPipeAndPassRemote());
 
   sensor_hal_client_.set_disconnect_handler(base::BindOnce(
       &AccelerometerProviderMojo::OnSensorHalClientFailure, this));

ash/accelerometer/accelerometer_reader.cc

@@ -4,27 +4,21 @@
 
 #include "ash/accelerometer/accelerometer_reader.h"
 
-#include <grp.h>
-
-#include "ash/accelerometer/accelerometer_file_reader.h"
-#include "ash/accelerometer/accelerometer_provider_mojo.h"
 #include "ash/shell.h"
 #include "ash/wm/tablet_mode/tablet_mode_controller.h"
 #include "base/no_destructor.h"
-#include "base/posix/eintr_wrapper.h"
 #include "base/sequenced_task_runner.h"
 #include "base/task/current_thread.h"
 #include "base/threading/sequenced_task_runner_handle.h"
+#include "chromeos/components/sensors/buildflags.h"
+#if BUILDFLAG(USE_IIOSERVICE)
+#include "ash/accelerometer/accelerometer_provider_mojo.h"
+#else  // !BUILDFLAG(USE_IIOSERVICE)
+#include "ash/accelerometer/accelerometer_file_reader.h"
+#endif  // BUILDFLAG(USE_IIOSERVICE)
 
 namespace ash {
 
-namespace {
-
-// Group name of IIO Service, used to check if IIO Service exists.
-constexpr char kIioServiceGroupName[] = "iioservice";
-
-}  // namespace
-
 // static
 AccelerometerReader* AccelerometerReader::GetInstance() {
   static base::NoDestructor<AccelerometerReader> accelerometer_reader;
@@ -62,17 +56,11 @@ void AccelerometerReader::SetECLidAngleDriverStatusForTesting(
 }
 
 AccelerometerReader::AccelerometerReader() {
-  char buf[1024];
-  struct group result;
-  struct group* resultp;
-
-  if (HANDLE_EINTR(getgrnam_r(kIioServiceGroupName, &result, buf, sizeof(buf),
-                              &resultp)) < 0 ||
-      !resultp) {
-    accelerometer_provider_ = new AccelerometerFileReader();
-  } else {
-    accelerometer_provider_ = new AccelerometerProviderMojo();
-  }
+#if BUILDFLAG(USE_IIOSERVICE)
+  accelerometer_provider_ = new AccelerometerProviderMojo();
+#else   // !BUILDFLAG(USE_IIOSERVICE)
+  accelerometer_provider_ = new AccelerometerFileReader();
+#endif  // BUILDFLAG(USE_IIOSERVICE)
 }
 
 AccelerometerReader::~AccelerometerReader() = default;