Sensors: MultiHal: Add HIDL-based Multi-Hal

Add the ability to use more than a single sensor HAL
to the HIDL sensor service.

Bug: 32022308
Change-Id: I99866adbbbee6d93350327aaaba136682ae069ae
diff --git a/sensors/1.0/default/Android.bp b/sensors/1.0/default/Android.bp
index 7fbe117..994febe 100644
--- a/sensors/1.0/default/Android.bp
+++ b/sensors/1.0/default/Android.bp
@@ -8,7 +8,6 @@
         "libhardware",
         "libhwbinder",
         "libbase",
-        "libcutils",
         "libutils",
         "libhidlbase",
         "libhidltransport",
@@ -16,6 +15,7 @@
     ],
     static_libs: [
         "android.hardware.sensors@1.0-convert",
+        "multihal",
     ],
     local_include_dirs: ["include/sensors"],
 }
@@ -30,7 +30,6 @@
         "libhardware",
         "libhwbinder",
         "libbase",
-        "libcutils",
         "libutils",
         "libhidlbase",
         "libhidltransport",
diff --git a/sensors/1.0/default/Android.mk b/sensors/1.0/default/Android.mk
index b2b2c60..f37c3cb 100644
--- a/sensors/1.0/default/Android.mk
+++ b/sensors/1.0/default/Android.mk
@@ -5,21 +5,21 @@
 LOCAL_MODULE := android.hardware.sensors@1.0-service
 LOCAL_INIT_RC := android.hardware.sensors@1.0-service.rc
 LOCAL_SRC_FILES := \
-	service.cpp \
+        service.cpp \
 
 LOCAL_SHARED_LIBRARIES := \
-	liblog \
-	libcutils \
-	libdl \
-	libbase \
-	libutils \
-	libhardware_legacy \
-	libhardware \
+        liblog \
+        libcutils \
+        libdl \
+        libbase \
+        libutils \
+        libhardware_legacy \
+        libhardware \
 
 LOCAL_SHARED_LIBRARIES += \
-	libhwbinder \
-	libhidlbase \
-	libhidltransport \
-	android.hardware.sensors@1.0 \
+        libhwbinder \
+        libhidlbase \
+        libhidltransport \
+        android.hardware.sensors@1.0 \
 
 include $(BUILD_EXECUTABLE)
diff --git a/sensors/1.0/default/Sensors.cpp b/sensors/1.0/default/Sensors.cpp
index ef052c3..c76369f 100644
--- a/sensors/1.0/default/Sensors.cpp
+++ b/sensors/1.0/default/Sensors.cpp
@@ -15,17 +15,29 @@
  */
 
 #include "Sensors.h"
-
 #include "convert.h"
+#include "multihal.h"
 
 #include <android-base/logging.h>
 
+#include <sys/stat.h>
+
 namespace android {
 namespace hardware {
 namespace sensors {
 namespace V1_0 {
 namespace implementation {
 
+/*
+ * If a multi-hal configuration file exists in the proper location,
+ * return true indicating we need to use multi-hal functionality.
+ */
+static bool UseMultiHal() {
+    const std::string& name = MULTI_HAL_CONFIG_FILE_PATH;
+    struct stat buffer;
+    return (stat (name.c_str(), &buffer) == 0);
+}
+
 static Result ResultFromStatus(status_t err) {
     switch (err) {
         case OK:
@@ -43,10 +55,14 @@
     : mInitCheck(NO_INIT),
       mSensorModule(nullptr),
       mSensorDevice(nullptr) {
-    status_t err = hw_get_module(
+    status_t err = OK;
+    if (UseMultiHal()) {
+        mSensorModule = ::get_multi_hal_module_info();
+    } else {
+        err = hw_get_module(
             SENSORS_HARDWARE_MODULE_ID,
             (hw_module_t const **)&mSensorModule);
-
+    }
     if (mSensorModule == NULL) {
         err = UNKNOWN_ERROR;
     }