gnss/aidl/vts/gnss_hal_test.cpp - android_hardware_interfaces - Gitiles

 /*
  * Copyright (C) 2020 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 #define LOG_TAG "GnssHalTest"

 #include "gnss_hal_test.h"
 #include <hidl/ServiceManagement.h>
 #include "Utils.h"

 using android::hardware::gnss::GnssConstellationType;
 using android::hardware::gnss::GnssLocation;
 using android::hardware::gnss::IGnss;
 using android::hardware::gnss::IGnssCallback;
 using android::hardware::gnss::common::Utils;
 using GnssConstellationTypeV2_0 = android::hardware::gnss::V2_0::GnssConstellationType;

 void GnssHalTest::SetUp() {
     // Get AIDL handle
     aidl_gnss_hal_ = android::waitForDeclaredService<IGnssAidl>(String16(GetParam().c_str()));
     ASSERT_NE(aidl_gnss_hal_, nullptr);
     ALOGD("AIDL Interface Version = %d", aidl_gnss_hal_->getInterfaceVersion());

     if (aidl_gnss_hal_->getInterfaceVersion() == 1) {
         const auto& hidlInstanceNames = android::hardware::getAllHalInstanceNames(
                 android::hardware::gnss::V2_1::IGnss::descriptor);
         gnss_hal_ = IGnss_V2_1::getService(hidlInstanceNames[0]);
         ASSERT_NE(gnss_hal_, nullptr);
     }

     SetUpGnssCallback();
 }

 void GnssHalTest::SetUpGnssCallback() {
     aidl_gnss_cb_ = new GnssCallbackAidl();
     ASSERT_NE(aidl_gnss_cb_, nullptr);

     auto status = aidl_gnss_hal_->setCallback(aidl_gnss_cb_);
     if (!status.isOk()) {
         ALOGE("Failed to setCallback");
     }
     ASSERT_TRUE(status.isOk());

     /*
      * Capabilities callback should trigger.
      */
     EXPECT_TRUE(aidl_gnss_cb_->capabilities_cbq_.retrieve(aidl_gnss_cb_->last_capabilities_,
                                                           TIMEOUT_SEC));
     EXPECT_EQ(aidl_gnss_cb_->capabilities_cbq_.calledCount(), 1);

     if (aidl_gnss_hal_->getInterfaceVersion() == 1) {
         // Invoke the super method.
         GnssHalTestTemplate<IGnss_V2_1>::SetUpGnssCallback();
     }
 }

 void GnssHalTest::CheckLocation(const GnssLocation& location, bool check_speed) {
     Utils::checkLocation(location, check_speed, /* check_more_accuracies= */ true);
 }

 void GnssHalTest::SetPositionMode(const int min_interval_msec, const bool low_power_mode) {
     if (aidl_gnss_hal_->getInterfaceVersion() == 1) {
         // Invoke the super method.
         return GnssHalTestTemplate<IGnss_V2_1>::SetPositionMode(min_interval_msec, low_power_mode);
     }

     const int kPreferredAccuracy = 0;  // Ideally perfect (matches GnssLocationProvider)
     const int kPreferredTimeMsec = 0;  // Ideally immediate

     auto status = aidl_gnss_hal_->setPositionMode(
             IGnss::GnssPositionMode::MS_BASED, IGnss::GnssPositionRecurrence::RECURRENCE_PERIODIC,
             min_interval_msec, kPreferredAccuracy, kPreferredTimeMsec, low_power_mode);

     ASSERT_TRUE(status.isOk());
 }

 bool GnssHalTest::StartAndCheckFirstLocation(const int min_interval_msec,
                                              const bool low_power_mode) {
     if (aidl_gnss_hal_->getInterfaceVersion() == 1) {
         // Invoke the super method.
         return GnssHalTestTemplate<IGnss_V2_1>::StartAndCheckFirstLocation(min_interval_msec,
                                                                            low_power_mode);
     }

     SetPositionMode(min_interval_msec, low_power_mode);
     auto result = aidl_gnss_hal_->start();

     EXPECT_TRUE(result.isOk());

     /*
      * GnssLocationProvider support of AGPS SUPL & XtraDownloader is not available in VTS,
      * so allow time to demodulate ephemeris over the air.
      */
     const int kFirstGnssLocationTimeoutSeconds = 75;

     EXPECT_TRUE(aidl_gnss_cb_->location_cbq_.retrieve(aidl_gnss_cb_->last_location_,
                                                       kFirstGnssLocationTimeoutSeconds));
     int locationCalledCount = aidl_gnss_cb_->location_cbq_.calledCount();
     EXPECT_EQ(locationCalledCount, 1);

     if (locationCalledCount > 0) {
         // don't require speed on first fix
         CheckLocation(aidl_gnss_cb_->last_location_, false);
         return true;
     }
     return false;
 }

 void GnssHalTest::StopAndClearLocations() {
     ALOGD("StopAndClearLocations");
     if (aidl_gnss_hal_->getInterfaceVersion() == 1) {
         // Invoke the super method.
         return GnssHalTestTemplate<IGnss_V2_1>::StopAndClearLocations();
     }

     auto status = aidl_gnss_hal_->stop();
     EXPECT_TRUE(status.isOk());

     /*
      * Clear notify/waiting counter, allowing up till the timeout after
      * the last reply for final startup messages to arrive (esp. system
      * info.)
      */
     while (aidl_gnss_cb_->location_cbq_.retrieve(aidl_gnss_cb_->last_location_, TIMEOUT_SEC)) {
     }
     aidl_gnss_cb_->location_cbq_.reset();
 }

 void GnssHalTest::StartAndCheckLocations(int count) {
     if (aidl_gnss_hal_->getInterfaceVersion() == 1) {
         // Invoke the super method.
         return GnssHalTestTemplate<IGnss_V2_1>::StartAndCheckLocations(count);
     }
     const int kMinIntervalMsec = 500;
     const int kLocationTimeoutSubsequentSec = 2;
     const bool kLowPowerMode = false;

     EXPECT_TRUE(StartAndCheckFirstLocation(kMinIntervalMsec, kLowPowerMode));

     for (int i = 1; i < count; i++) {
         EXPECT_TRUE(aidl_gnss_cb_->location_cbq_.retrieve(aidl_gnss_cb_->last_location_,
                                                           kLocationTimeoutSubsequentSec));
         int locationCalledCount = aidl_gnss_cb_->location_cbq_.calledCount();
         EXPECT_EQ(locationCalledCount, i + 1);
         // Don't cause confusion by checking details if no location yet
         if (locationCalledCount > 0) {
             // Should be more than 1 location by now, but if not, still don't check first fix speed
             CheckLocation(aidl_gnss_cb_->last_location_, locationCalledCount > 1);
         }
     }
 }

 std::list<std::vector<IGnssCallback::GnssSvInfo>> GnssHalTest::convertToAidl(
         const std::list<hidl_vec<IGnssCallback_2_1::GnssSvInfo>>& sv_info_list) {
     std::list<std::vector<IGnssCallback::GnssSvInfo>> aidl_sv_info_list;
     for (const auto& sv_info_vec : sv_info_list) {
         std::vector<IGnssCallback::GnssSvInfo> aidl_sv_info_vec;
         for (const auto& sv_info : sv_info_vec) {
             IGnssCallback::GnssSvInfo aidl_sv_info;
             aidl_sv_info.svid = sv_info.v2_0.v1_0.svid;
             aidl_sv_info.constellation =
                     static_cast<GnssConstellationType>(sv_info.v2_0.constellation);
             aidl_sv_info.cN0Dbhz = sv_info.v2_0.v1_0.cN0Dbhz;
             aidl_sv_info.basebandCN0DbHz = sv_info.basebandCN0DbHz;
             aidl_sv_info.elevationDegrees = sv_info.v2_0.v1_0.elevationDegrees;
             aidl_sv_info.azimuthDegrees = sv_info.v2_0.v1_0.azimuthDegrees;
             aidl_sv_info.carrierFrequencyHz = (int64_t)sv_info.v2_0.v1_0.carrierFrequencyHz;
             aidl_sv_info.svFlag = (int)sv_info.v2_0.v1_0.svFlag;
             aidl_sv_info_vec.push_back(aidl_sv_info);
         }
         aidl_sv_info_list.push_back(aidl_sv_info_vec);
     }
     return aidl_sv_info_list;
 }

 /*
  * FindStrongFrequentNonGpsSource:
  *
  * Search through a GnssSvStatus list for the strongest non-GPS satellite observed enough times
  *
  * returns the strongest source,
  *         or a source with constellation == UNKNOWN if none are found sufficient times
  */
 BlocklistedSource GnssHalTest::FindStrongFrequentNonGpsSource(
         const std::list<hidl_vec<IGnssCallback_2_1::GnssSvInfo>> sv_info_list,
         const int min_observations) {
     return FindStrongFrequentNonGpsSource(convertToAidl(sv_info_list), min_observations);
 }

 BlocklistedSource GnssHalTest::FindStrongFrequentNonGpsSource(
         const std::list<std::vector<IGnssCallback::GnssSvInfo>> sv_info_list,
         const int min_observations) {
     std::map<ComparableBlocklistedSource, SignalCounts> mapSignals;

     for (const auto& sv_info_vec : sv_info_list) {
         for (uint32_t iSv = 0; iSv < sv_info_vec.size(); iSv++) {
             const auto& gnss_sv = sv_info_vec[iSv];
             if ((gnss_sv.svFlag & (int)IGnssCallback::GnssSvFlags::USED_IN_FIX) &&
                 (gnss_sv.constellation != GnssConstellationType::GPS)) {
                 ComparableBlocklistedSource source;
                 source.id.svid = gnss_sv.svid;
                 source.id.constellation = gnss_sv.constellation;

                 const auto& itSignal = mapSignals.find(source);
                 if (itSignal == mapSignals.end()) {
                     SignalCounts counts;
                     counts.observations = 1;
                     counts.max_cn0_dbhz = gnss_sv.cN0Dbhz;
                     mapSignals.insert(
                             std::pair<ComparableBlocklistedSource, SignalCounts>(source, counts));
                 } else {
                     itSignal->second.observations++;
                     if (itSignal->second.max_cn0_dbhz < gnss_sv.cN0Dbhz) {
                         itSignal->second.max_cn0_dbhz = gnss_sv.cN0Dbhz;
                     }
                 }
             }
         }
     }

     float max_cn0_dbhz_with_sufficient_count = 0.;
     int total_observation_count = 0;
     int blocklisted_source_count_observation = 0;

     ComparableBlocklistedSource source_to_blocklist;  // initializes to zero = UNKNOWN constellation
     for (auto const& pairSignal : mapSignals) {
         total_observation_count += pairSignal.second.observations;
         if ((pairSignal.second.observations >= min_observations) &&
             (pairSignal.second.max_cn0_dbhz > max_cn0_dbhz_with_sufficient_count)) {
             source_to_blocklist = pairSignal.first;
             blocklisted_source_count_observation = pairSignal.second.observations;
             max_cn0_dbhz_with_sufficient_count = pairSignal.second.max_cn0_dbhz;
         }
     }
     ALOGD("Among %d observations, chose svid %d, constellation %d, "
           "with %d observations at %.1f max CNo",
           total_observation_count, source_to_blocklist.id.svid,
           (int)source_to_blocklist.id.constellation, blocklisted_source_count_observation,
           max_cn0_dbhz_with_sufficient_count);

     return source_to_blocklist.id;
 }

 GnssConstellationType GnssHalTest::startLocationAndGetNonGpsConstellation(
         const int locations_to_await, const int gnss_sv_info_list_timeout) {
     if (aidl_gnss_hal_->getInterfaceVersion() == 1) {
         return static_cast<GnssConstellationType>(
                 GnssHalTestTemplate<IGnss_V2_1>::startLocationAndGetNonGpsConstellation(
                         locations_to_await, gnss_sv_info_list_timeout));
     }
     aidl_gnss_cb_->location_cbq_.reset();
     StartAndCheckLocations(locations_to_await);
     const int location_called_count = aidl_gnss_cb_->location_cbq_.calledCount();

     // Tolerate 1 less sv status to handle edge cases in reporting.
     int sv_info_list_cbq_size = aidl_gnss_cb_->sv_info_list_cbq_.size();
     EXPECT_GE(sv_info_list_cbq_size + 1, locations_to_await);
     ALOGD("Observed %d GnssSvInfo, while awaiting %d Locations (%d received)",
           sv_info_list_cbq_size, locations_to_await, location_called_count);

     // Find first non-GPS constellation to blocklist
     GnssConstellationType constellation_to_blocklist = GnssConstellationType::UNKNOWN;
     for (int i = 0; i < sv_info_list_cbq_size; ++i) {
         std::vector<IGnssCallback::GnssSvInfo> sv_info_vec;
         aidl_gnss_cb_->sv_info_list_cbq_.retrieve(sv_info_vec, gnss_sv_info_list_timeout);
         for (uint32_t iSv = 0; iSv < sv_info_vec.size(); iSv++) {
             auto& gnss_sv = sv_info_vec[iSv];
             if ((gnss_sv.svFlag & (uint32_t)IGnssCallback::GnssSvFlags::USED_IN_FIX) &&
                 (gnss_sv.constellation != GnssConstellationType::UNKNOWN) &&
                 (gnss_sv.constellation != GnssConstellationType::GPS)) {
                 // found a non-GPS constellation
                 constellation_to_blocklist = gnss_sv.constellation;
                 break;
             }
         }
         if (constellation_to_blocklist != GnssConstellationType::UNKNOWN) {
             break;
         }
     }

     if (constellation_to_blocklist == GnssConstellationType::UNKNOWN) {
         ALOGI("No non-GPS constellations found, constellation blocklist test less effective.");
         // Proceed functionally to blocklist something.
         constellation_to_blocklist = GnssConstellationType::GLONASS;
     }

     return constellation_to_blocklist;
 }
	/*
	* Copyright (C) 2020 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	#define LOG_TAG "GnssHalTest"

	#include "gnss_hal_test.h"
	#include <hidl/ServiceManagement.h>
	#include "Utils.h"

	using android::hardware::gnss::GnssConstellationType;
	using android::hardware::gnss::GnssLocation;
	using android::hardware::gnss::IGnss;
	using android::hardware::gnss::IGnssCallback;
	using android::hardware::gnss::common::Utils;
	using GnssConstellationTypeV2_0 = android::hardware::gnss::V2_0::GnssConstellationType;

	void GnssHalTest::SetUp() {
	// Get AIDL handle
	aidl_gnss_hal_ = android::waitForDeclaredService<IGnssAidl>(String16(GetParam().c_str()));
	ASSERT_NE(aidl_gnss_hal_, nullptr);
	ALOGD("AIDL Interface Version = %d", aidl_gnss_hal_->getInterfaceVersion());

	if (aidl_gnss_hal_->getInterfaceVersion() == 1) {
	const auto& hidlInstanceNames = android::hardware::getAllHalInstanceNames(
	android::hardware::gnss::V2_1::IGnss::descriptor);
	gnss_hal_ = IGnss_V2_1::getService(hidlInstanceNames[0]);
	ASSERT_NE(gnss_hal_, nullptr);
	}

	SetUpGnssCallback();
	}

	void GnssHalTest::SetUpGnssCallback() {
	aidl_gnss_cb_ = new GnssCallbackAidl();
	ASSERT_NE(aidl_gnss_cb_, nullptr);

	auto status = aidl_gnss_hal_->setCallback(aidl_gnss_cb_);
	if (!status.isOk()) {
	ALOGE("Failed to setCallback");
	}
	ASSERT_TRUE(status.isOk());

	/*
	* Capabilities callback should trigger.
	*/
	EXPECT_TRUE(aidl_gnss_cb_->capabilities_cbq_.retrieve(aidl_gnss_cb_->last_capabilities_,
	TIMEOUT_SEC));
	EXPECT_EQ(aidl_gnss_cb_->capabilities_cbq_.calledCount(), 1);

	if (aidl_gnss_hal_->getInterfaceVersion() == 1) {
	// Invoke the super method.
	GnssHalTestTemplate<IGnss_V2_1>::SetUpGnssCallback();
	}
	}

	void GnssHalTest::CheckLocation(const GnssLocation& location, bool check_speed) {
	Utils::checkLocation(location, check_speed, /* check_more_accuracies= */ true);
	}

	void GnssHalTest::SetPositionMode(const int min_interval_msec, const bool low_power_mode) {
	if (aidl_gnss_hal_->getInterfaceVersion() == 1) {
	// Invoke the super method.
	return GnssHalTestTemplate<IGnss_V2_1>::SetPositionMode(min_interval_msec, low_power_mode);
	}

	const int kPreferredAccuracy = 0; // Ideally perfect (matches GnssLocationProvider)
	const int kPreferredTimeMsec = 0; // Ideally immediate

	auto status = aidl_gnss_hal_->setPositionMode(
	IGnss::GnssPositionMode::MS_BASED, IGnss::GnssPositionRecurrence::RECURRENCE_PERIODIC,
	min_interval_msec, kPreferredAccuracy, kPreferredTimeMsec, low_power_mode);

	ASSERT_TRUE(status.isOk());
	}

	bool GnssHalTest::StartAndCheckFirstLocation(const int min_interval_msec,
	const bool low_power_mode) {
	if (aidl_gnss_hal_->getInterfaceVersion() == 1) {
	// Invoke the super method.
	return GnssHalTestTemplate<IGnss_V2_1>::StartAndCheckFirstLocation(min_interval_msec,
	low_power_mode);
	}

	SetPositionMode(min_interval_msec, low_power_mode);
	auto result = aidl_gnss_hal_->start();

	EXPECT_TRUE(result.isOk());

	/*
	* GnssLocationProvider support of AGPS SUPL & XtraDownloader is not available in VTS,
	* so allow time to demodulate ephemeris over the air.
	*/
	const int kFirstGnssLocationTimeoutSeconds = 75;

	EXPECT_TRUE(aidl_gnss_cb_->location_cbq_.retrieve(aidl_gnss_cb_->last_location_,
	kFirstGnssLocationTimeoutSeconds));
	int locationCalledCount = aidl_gnss_cb_->location_cbq_.calledCount();
	EXPECT_EQ(locationCalledCount, 1);

	if (locationCalledCount > 0) {
	// don't require speed on first fix
	CheckLocation(aidl_gnss_cb_->last_location_, false);
	return true;
	}
	return false;
	}

	void GnssHalTest::StopAndClearLocations() {
	ALOGD("StopAndClearLocations");
	if (aidl_gnss_hal_->getInterfaceVersion() == 1) {
	// Invoke the super method.
	return GnssHalTestTemplate<IGnss_V2_1>::StopAndClearLocations();
	}

	auto status = aidl_gnss_hal_->stop();
	EXPECT_TRUE(status.isOk());

	/*
	* Clear notify/waiting counter, allowing up till the timeout after
	* the last reply for final startup messages to arrive (esp. system
	* info.)
	*/
	while (aidl_gnss_cb_->location_cbq_.retrieve(aidl_gnss_cb_->last_location_, TIMEOUT_SEC)) {
	}
	aidl_gnss_cb_->location_cbq_.reset();
	}

	void GnssHalTest::StartAndCheckLocations(int count) {
	if (aidl_gnss_hal_->getInterfaceVersion() == 1) {
	// Invoke the super method.
	return GnssHalTestTemplate<IGnss_V2_1>::StartAndCheckLocations(count);
	}
	const int kMinIntervalMsec = 500;
	const int kLocationTimeoutSubsequentSec = 2;
	const bool kLowPowerMode = false;

	EXPECT_TRUE(StartAndCheckFirstLocation(kMinIntervalMsec, kLowPowerMode));

	for (int i = 1; i < count; i++) {
	EXPECT_TRUE(aidl_gnss_cb_->location_cbq_.retrieve(aidl_gnss_cb_->last_location_,
	kLocationTimeoutSubsequentSec));
	int locationCalledCount = aidl_gnss_cb_->location_cbq_.calledCount();
	EXPECT_EQ(locationCalledCount, i + 1);
	// Don't cause confusion by checking details if no location yet
	if (locationCalledCount > 0) {
	// Should be more than 1 location by now, but if not, still don't check first fix speed
	CheckLocation(aidl_gnss_cb_->last_location_, locationCalledCount > 1);
	}
	}
	}

	std::list<std::vector<IGnssCallback::GnssSvInfo>> GnssHalTest::convertToAidl(
	const std::list<hidl_vec<IGnssCallback_2_1::GnssSvInfo>>& sv_info_list) {
	std::list<std::vector<IGnssCallback::GnssSvInfo>> aidl_sv_info_list;
	for (const auto& sv_info_vec : sv_info_list) {
	std::vector<IGnssCallback::GnssSvInfo> aidl_sv_info_vec;
	for (const auto& sv_info : sv_info_vec) {
	IGnssCallback::GnssSvInfo aidl_sv_info;
	aidl_sv_info.svid = sv_info.v2_0.v1_0.svid;
	aidl_sv_info.constellation =
	static_cast<GnssConstellationType>(sv_info.v2_0.constellation);
	aidl_sv_info.cN0Dbhz = sv_info.v2_0.v1_0.cN0Dbhz;
	aidl_sv_info.basebandCN0DbHz = sv_info.basebandCN0DbHz;
	aidl_sv_info.elevationDegrees = sv_info.v2_0.v1_0.elevationDegrees;
	aidl_sv_info.azimuthDegrees = sv_info.v2_0.v1_0.azimuthDegrees;
	aidl_sv_info.carrierFrequencyHz = (int64_t)sv_info.v2_0.v1_0.carrierFrequencyHz;
	aidl_sv_info.svFlag = (int)sv_info.v2_0.v1_0.svFlag;
	aidl_sv_info_vec.push_back(aidl_sv_info);
	}
	aidl_sv_info_list.push_back(aidl_sv_info_vec);
	}
	return aidl_sv_info_list;
	}

	/*
	* FindStrongFrequentNonGpsSource:
	*
	* Search through a GnssSvStatus list for the strongest non-GPS satellite observed enough times
	*
	* returns the strongest source,
	* or a source with constellation == UNKNOWN if none are found sufficient times
	*/
	BlocklistedSource GnssHalTest::FindStrongFrequentNonGpsSource(
	const std::list<hidl_vec<IGnssCallback_2_1::GnssSvInfo>> sv_info_list,
	const int min_observations) {
	return FindStrongFrequentNonGpsSource(convertToAidl(sv_info_list), min_observations);
	}

	BlocklistedSource GnssHalTest::FindStrongFrequentNonGpsSource(
	const std::list<std::vector<IGnssCallback::GnssSvInfo>> sv_info_list,
	const int min_observations) {
	std::map<ComparableBlocklistedSource, SignalCounts> mapSignals;

	for (const auto& sv_info_vec : sv_info_list) {
	for (uint32_t iSv = 0; iSv < sv_info_vec.size(); iSv++) {
	const auto& gnss_sv = sv_info_vec[iSv];
	if ((gnss_sv.svFlag & (int)IGnssCallback::GnssSvFlags::USED_IN_FIX) &&
	(gnss_sv.constellation != GnssConstellationType::GPS)) {
	ComparableBlocklistedSource source;
	source.id.svid = gnss_sv.svid;
	source.id.constellation = gnss_sv.constellation;

	const auto& itSignal = mapSignals.find(source);
	if (itSignal == mapSignals.end()) {
	SignalCounts counts;
	counts.observations = 1;
	counts.max_cn0_dbhz = gnss_sv.cN0Dbhz;
	mapSignals.insert(
	std::pair<ComparableBlocklistedSource, SignalCounts>(source, counts));
	} else {
	itSignal->second.observations++;
	if (itSignal->second.max_cn0_dbhz < gnss_sv.cN0Dbhz) {
	itSignal->second.max_cn0_dbhz = gnss_sv.cN0Dbhz;
	}
	}
	}
	}
	}

	float max_cn0_dbhz_with_sufficient_count = 0.;
	int total_observation_count = 0;
	int blocklisted_source_count_observation = 0;

	ComparableBlocklistedSource source_to_blocklist; // initializes to zero = UNKNOWN constellation
	for (auto const& pairSignal : mapSignals) {
	total_observation_count += pairSignal.second.observations;
	if ((pairSignal.second.observations >= min_observations) &&
	(pairSignal.second.max_cn0_dbhz > max_cn0_dbhz_with_sufficient_count)) {
	source_to_blocklist = pairSignal.first;
	blocklisted_source_count_observation = pairSignal.second.observations;
	max_cn0_dbhz_with_sufficient_count = pairSignal.second.max_cn0_dbhz;
	}
	}
	ALOGD("Among %d observations, chose svid %d, constellation %d, "
	"with %d observations at %.1f max CNo",
	total_observation_count, source_to_blocklist.id.svid,
	(int)source_to_blocklist.id.constellation, blocklisted_source_count_observation,
	max_cn0_dbhz_with_sufficient_count);

	return source_to_blocklist.id;
	}

	GnssConstellationType GnssHalTest::startLocationAndGetNonGpsConstellation(
	const int locations_to_await, const int gnss_sv_info_list_timeout) {
	if (aidl_gnss_hal_->getInterfaceVersion() == 1) {
	return static_cast<GnssConstellationType>(
	GnssHalTestTemplate<IGnss_V2_1>::startLocationAndGetNonGpsConstellation(
	locations_to_await, gnss_sv_info_list_timeout));
	}
	aidl_gnss_cb_->location_cbq_.reset();
	StartAndCheckLocations(locations_to_await);
	const int location_called_count = aidl_gnss_cb_->location_cbq_.calledCount();

	// Tolerate 1 less sv status to handle edge cases in reporting.
	int sv_info_list_cbq_size = aidl_gnss_cb_->sv_info_list_cbq_.size();
	EXPECT_GE(sv_info_list_cbq_size + 1, locations_to_await);
	ALOGD("Observed %d GnssSvInfo, while awaiting %d Locations (%d received)",
	sv_info_list_cbq_size, locations_to_await, location_called_count);

	// Find first non-GPS constellation to blocklist
	GnssConstellationType constellation_to_blocklist = GnssConstellationType::UNKNOWN;
	for (int i = 0; i < sv_info_list_cbq_size; ++i) {
	std::vector<IGnssCallback::GnssSvInfo> sv_info_vec;
	aidl_gnss_cb_->sv_info_list_cbq_.retrieve(sv_info_vec, gnss_sv_info_list_timeout);
	for (uint32_t iSv = 0; iSv < sv_info_vec.size(); iSv++) {
	auto& gnss_sv = sv_info_vec[iSv];
	if ((gnss_sv.svFlag & (uint32_t)IGnssCallback::GnssSvFlags::USED_IN_FIX) &&
	(gnss_sv.constellation != GnssConstellationType::UNKNOWN) &&
	(gnss_sv.constellation != GnssConstellationType::GPS)) {
	// found a non-GPS constellation
	constellation_to_blocklist = gnss_sv.constellation;
	break;
	}
	}
	if (constellation_to_blocklist != GnssConstellationType::UNKNOWN) {
	break;
	}
	}

	if (constellation_to_blocklist == GnssConstellationType::UNKNOWN) {
	ALOGI("No non-GPS constellations found, constellation blocklist test less effective.");
	// Proceed functionally to blocklist something.
	constellation_to_blocklist = GnssConstellationType::GLONASS;
	}

	return constellation_to_blocklist;
	}