libs/graphicsenv/GraphicsEnv.cpp

/*
 * Copyright 2017 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 ATRACE_TAG ATRACE_TAG_GRAPHICS

//#define LOG_NDEBUG 1
#define LOG_TAG "GraphicsEnv"

#include <graphicsenv/GraphicsEnv.h>

#include <dlfcn.h>
#include <unistd.h>

#include <android-base/file.h>
#include <android-base/properties.h>
#include <android-base/strings.h>
#include <android/dlext.h>
#include <binder/IServiceManager.h>
#include <graphicsenv/IGpuService.h>
#include <log/log.h>
#include <nativeloader/dlext_namespaces.h>
#include <sys/prctl.h>
#include <utils/Trace.h>

#include <memory>
#include <string>
#include <thread>

// TODO(b/159240322): Extend this to x86 ABI.
#if defined(__LP64__)
#define UPDATABLE_DRIVER_ABI "arm64-v8a"
#else
#define UPDATABLE_DRIVER_ABI "armeabi-v7a"
#endif // defined(__LP64__)

// TODO(ianelliott@): Get the following from an ANGLE header:
#define CURRENT_ANGLE_API_VERSION 2 // Current API verion we are targetting
// Version-2 API:
typedef bool (*fpANGLEGetFeatureSupportUtilAPIVersion)(unsigned int* versionToUse);
typedef bool (*fpANGLEAndroidParseRulesString)(const char* rulesString, void** rulesHandle,
                                               int* rulesVersion);
typedef bool (*fpANGLEGetSystemInfo)(void** handle);
typedef bool (*fpANGLEAddDeviceInfoToSystemInfo)(const char* deviceMfr, const char* deviceModel,
                                                 void* handle);
typedef bool (*fpANGLEShouldBeUsedForApplication)(void* rulesHandle, int rulesVersion,
                                                  void* systemInfoHandle, const char* appName);
typedef bool (*fpANGLEFreeRulesHandle)(void* handle);
typedef bool (*fpANGLEFreeSystemInfoHandle)(void* handle);

namespace {
static bool isVndkEnabled() {
#ifdef __BIONIC__
    static bool isVndkEnabled = android::base::GetProperty("ro.vndk.version", "") != "";
    return isVndkEnabled;
#endif
    return false;
}
} // namespace

namespace android {

enum NativeLibrary {
    LLNDK = 0,
    VNDKSP = 1,
};

static constexpr const char* kNativeLibrariesSystemConfigPath[] =
        {"/apex/com.android.vndk.v{}/etc/llndk.libraries.{}.txt",
         "/apex/com.android.vndk.v{}/etc/vndksp.libraries.{}.txt"};

static const char* kLlndkLibrariesTxtPath = "/system/etc/llndk.libraries.txt";

static std::string vndkVersionStr() {
#ifdef __BIONIC__
    return base::GetProperty("ro.vndk.version", "");
#endif
    return "";
}

static void insertVndkVersionStr(std::string* fileName) {
    LOG_ALWAYS_FATAL_IF(!fileName, "fileName should never be nullptr");
    std::string version = vndkVersionStr();
    size_t pos = fileName->find("{}");
    while (pos != std::string::npos) {
        fileName->replace(pos, 2, version);
        pos = fileName->find("{}", pos + version.size());
    }
}

static bool readConfig(const std::string& configFile, std::vector<std::string>* soNames) {
    // Read list of public native libraries from the config file.
    std::string fileContent;
    if (!base::ReadFileToString(configFile, &fileContent)) {
        return false;
    }

    std::vector<std::string> lines = base::Split(fileContent, "\n");

    for (auto& line : lines) {
        auto trimmedLine = base::Trim(line);
        if (!trimmedLine.empty()) {
            soNames->push_back(trimmedLine);
        }
    }

    return true;
}

static const std::string getSystemNativeLibraries(NativeLibrary type) {
    std::string nativeLibrariesSystemConfig = "";

    if (!isVndkEnabled() && type == NativeLibrary::LLNDK) {
        nativeLibrariesSystemConfig = kLlndkLibrariesTxtPath;
    } else {
        nativeLibrariesSystemConfig = kNativeLibrariesSystemConfigPath[type];
        insertVndkVersionStr(&nativeLibrariesSystemConfig);
    }

    std::vector<std::string> soNames;
    if (!readConfig(nativeLibrariesSystemConfig, &soNames)) {
        ALOGE("Failed to retrieve library names from %s", nativeLibrariesSystemConfig.c_str());
        return "";
    }

    return base::Join(soNames, ':');
}

static sp<IGpuService> getGpuService() {
    static const sp<IBinder> binder = defaultServiceManager()->checkService(String16("gpu"));
    if (!binder) {
        ALOGE("Failed to get gpu service");
        return nullptr;
    }

    return interface_cast<IGpuService>(binder);
}

/*static*/ GraphicsEnv& GraphicsEnv::getInstance() {
    static GraphicsEnv env;
    return env;
}

bool GraphicsEnv::isDebuggable() {
    // This flag determines if the application is marked debuggable
    bool appDebuggable = prctl(PR_GET_DUMPABLE, 0, 0, 0, 0) > 0;

    // This flag is set only in `debuggable` builds of the platform
#if defined(ANDROID_DEBUGGABLE)
    bool platformDebuggable = true;
#else
    bool platformDebuggable = false;
#endif

    ALOGV("GraphicsEnv::isDebuggable returning appDebuggable=%s || platformDebuggable=%s",
          appDebuggable ? "true" : "false", platformDebuggable ? "true" : "false");

    return appDebuggable || platformDebuggable;
}

/**
 * APIs for updatable graphics drivers
 */

void GraphicsEnv::setDriverPathAndSphalLibraries(const std::string& path,
                                                 const std::string& sphalLibraries) {
    if (!mDriverPath.empty() || !mSphalLibraries.empty()) {
        ALOGV("ignoring attempt to change driver path from '%s' to '%s' or change sphal libraries "
              "from '%s' to '%s'",
              mDriverPath.c_str(), path.c_str(), mSphalLibraries.c_str(), sphalLibraries.c_str());
        return;
    }
    ALOGV("setting driver path to '%s' and sphal libraries to '%s'", path.c_str(),
          sphalLibraries.c_str());
    mDriverPath = path;
    mSphalLibraries = sphalLibraries;
}

// Return true if all the required libraries from vndk and sphal namespace are
// linked to the driver namespace correctly.
bool GraphicsEnv::linkDriverNamespaceLocked(android_namespace_t* destNamespace,
                                            android_namespace_t* vndkNamespace,
                                            const std::string& sharedSphalLibraries) {
    const std::string llndkLibraries = getSystemNativeLibraries(NativeLibrary::LLNDK);
    if (llndkLibraries.empty()) {
        return false;
    }
    if (!android_link_namespaces(destNamespace, nullptr, llndkLibraries.c_str())) {
        ALOGE("Failed to link default namespace[%s]", dlerror());
        return false;
    }

    const std::string vndkspLibraries = getSystemNativeLibraries(NativeLibrary::VNDKSP);
    if (vndkspLibraries.empty()) {
        return false;
    }
    if (!android_link_namespaces(destNamespace, vndkNamespace, vndkspLibraries.c_str())) {
        ALOGE("Failed to link vndk namespace[%s]", dlerror());
        return false;
    }

    if (sharedSphalLibraries.empty()) {
        return true;
    }

    // Make additional libraries in sphal to be accessible
    auto sphalNamespace = android_get_exported_namespace("sphal");
    if (!sphalNamespace) {
        ALOGE("Depend on these libraries[%s] in sphal, but failed to get sphal namespace",
              sharedSphalLibraries.c_str());
        return false;
    }

    if (!android_link_namespaces(destNamespace, sphalNamespace, sharedSphalLibraries.c_str())) {
        ALOGE("Failed to link sphal namespace[%s]", dlerror());
        return false;
    }

    return true;
}

android_namespace_t* GraphicsEnv::getDriverNamespace() {
    std::lock_guard<std::mutex> lock(mNamespaceMutex);

    if (mDriverNamespace) {
        return mDriverNamespace;
    }

    if (mDriverPath.empty()) {
        // For an application process, driver path is empty means this application is not opted in
        // to use updatable driver. Application process doesn't have the ability to set up
        // environment variables and hence before `getenv` call will return.
        // For a process that is not an application process, if it's run from an environment,
        // for example shell, where environment variables can be set, then it can opt into using
        // udpatable driver by setting UPDATABLE_GFX_DRIVER to 1. By setting to 1 the developer
        // driver will be used currently.
        // TODO(b/159240322) Support the production updatable driver.
        const char* id = getenv("UPDATABLE_GFX_DRIVER");
        if (id == nullptr || std::strcmp(id, "1") != 0) {
            return nullptr;
        }
        const sp<IGpuService> gpuService = getGpuService();
        if (!gpuService) {
            return nullptr;
        }
        mDriverPath = gpuService->getUpdatableDriverPath();
        if (mDriverPath.empty()) {
            return nullptr;
        }
        mDriverPath.append(UPDATABLE_DRIVER_ABI);
        ALOGI("Driver path is setup via UPDATABLE_GFX_DRIVER: %s", mDriverPath.c_str());
    }

    auto vndkNamespace = android_get_exported_namespace("vndk");
    if (!vndkNamespace) {
        mDriverNamespace = nullptr;
        return mDriverNamespace;
    }

    mDriverNamespace = android_create_namespace("updatable gfx driver",
                                                mDriverPath.c_str(), // ld_library_path
                                                mDriverPath.c_str(), // default_library_path
                                                ANDROID_NAMESPACE_TYPE_ISOLATED,
                                                nullptr, // permitted_when_isolated_path
                                                nullptr);

    if (!linkDriverNamespaceLocked(mDriverNamespace, vndkNamespace, mSphalLibraries)) {
        mDriverNamespace = nullptr;
    }

    return mDriverNamespace;
}

std::string GraphicsEnv::getDriverPath() const {
    return mDriverPath;
}

/**
 * APIs for GpuStats
 */

void GraphicsEnv::hintActivityLaunch() {
    ATRACE_CALL();

    {
        std::lock_guard<std::mutex> lock(mStatsLock);
        if (mActivityLaunched) return;
        mActivityLaunched = true;
    }

    std::thread trySendGpuStatsThread([this]() {
        // If there's already graphics driver preloaded in the process, just send
        // the stats info to GpuStats directly through async binder.
        std::lock_guard<std::mutex> lock(mStatsLock);
        if (mGpuStats.glDriverToSend) {
            mGpuStats.glDriverToSend = false;
            sendGpuStatsLocked(GpuStatsInfo::Api::API_GL, true, mGpuStats.glDriverLoadingTime);
        }
        if (mGpuStats.vkDriverToSend) {
            mGpuStats.vkDriverToSend = false;
            sendGpuStatsLocked(GpuStatsInfo::Api::API_VK, true, mGpuStats.vkDriverLoadingTime);
        }
    });
    trySendGpuStatsThread.detach();
}

void GraphicsEnv::setGpuStats(const std::string& driverPackageName,
                              const std::string& driverVersionName, uint64_t driverVersionCode,
                              int64_t driverBuildTime, const std::string& appPackageName,
                              const int vulkanVersion) {
    ATRACE_CALL();

    std::lock_guard<std::mutex> lock(mStatsLock);
    ALOGV("setGpuStats:\n"
          "\tdriverPackageName[%s]\n"
          "\tdriverVersionName[%s]\n"
          "\tdriverVersionCode[%" PRIu64 "]\n"
          "\tdriverBuildTime[%" PRId64 "]\n"
          "\tappPackageName[%s]\n"
          "\tvulkanVersion[%d]\n",
          driverPackageName.c_str(), driverVersionName.c_str(), driverVersionCode, driverBuildTime,
          appPackageName.c_str(), vulkanVersion);

    mGpuStats.driverPackageName = driverPackageName;
    mGpuStats.driverVersionName = driverVersionName;
    mGpuStats.driverVersionCode = driverVersionCode;
    mGpuStats.driverBuildTime = driverBuildTime;
    mGpuStats.appPackageName = appPackageName;
    mGpuStats.vulkanVersion = vulkanVersion;
}

void GraphicsEnv::setDriverToLoad(GpuStatsInfo::Driver driver) {
    ATRACE_CALL();

    std::lock_guard<std::mutex> lock(mStatsLock);
    switch (driver) {
        case GpuStatsInfo::Driver::GL:
        case GpuStatsInfo::Driver::GL_UPDATED:
        case GpuStatsInfo::Driver::ANGLE: {
            if (mGpuStats.glDriverToLoad == GpuStatsInfo::Driver::NONE ||
                mGpuStats.glDriverToLoad == GpuStatsInfo::Driver::GL) {
                mGpuStats.glDriverToLoad = driver;
                break;
            }

            if (mGpuStats.glDriverFallback == GpuStatsInfo::Driver::NONE) {
                mGpuStats.glDriverFallback = driver;
            }
            break;
        }
        case GpuStatsInfo::Driver::VULKAN:
        case GpuStatsInfo::Driver::VULKAN_UPDATED: {
            if (mGpuStats.vkDriverToLoad == GpuStatsInfo::Driver::NONE ||
                mGpuStats.vkDriverToLoad == GpuStatsInfo::Driver::VULKAN) {
                mGpuStats.vkDriverToLoad = driver;
                break;
            }

            if (mGpuStats.vkDriverFallback == GpuStatsInfo::Driver::NONE) {
                mGpuStats.vkDriverFallback = driver;
            }
            break;
        }
        default:
            break;
    }
}

void GraphicsEnv::setDriverLoaded(GpuStatsInfo::Api api, bool isDriverLoaded,
                                  int64_t driverLoadingTime) {
    ATRACE_CALL();

    std::lock_guard<std::mutex> lock(mStatsLock);
    if (api == GpuStatsInfo::Api::API_GL) {
        mGpuStats.glDriverToSend = true;
        mGpuStats.glDriverLoadingTime = driverLoadingTime;
    } else {
        mGpuStats.vkDriverToSend = true;
        mGpuStats.vkDriverLoadingTime = driverLoadingTime;
    }

    sendGpuStatsLocked(api, isDriverLoaded, driverLoadingTime);
}

// Hash function to calculate hash for null-terminated Vulkan extension names
// We store hash values of the extensions, rather than the actual names or
// indices to be able to support new extensions easily, avoid creating
// a table of 'known' extensions inside Android and reduce the runtime overhead.
static uint64_t calculateExtensionHash(const char* word) {
    if (!word) {
        return 0;
    }
    const size_t wordLen = strlen(word);
    const uint32_t seed = 167;
    uint64_t hash = 0;
    for (size_t i = 0; i < wordLen; i++) {
        hash = (hash * seed) + word[i];
    }
    return hash;
}

void GraphicsEnv::setVulkanInstanceExtensions(uint32_t enabledExtensionCount,
                                              const char* const* ppEnabledExtensionNames) {
    ATRACE_CALL();
    if (enabledExtensionCount == 0 || ppEnabledExtensionNames == nullptr) {
        return;
    }

    const uint32_t maxNumStats = android::GpuStatsAppInfo::MAX_NUM_EXTENSIONS;
    uint64_t extensionHashes[maxNumStats];
    const uint32_t numStats = std::min(enabledExtensionCount, maxNumStats);
    for(uint32_t i = 0; i < numStats; i++) {
        extensionHashes[i] = calculateExtensionHash(ppEnabledExtensionNames[i]);
    }
    setTargetStatsArray(android::GpuStatsInfo::Stats::VULKAN_INSTANCE_EXTENSION,
                        extensionHashes, numStats);
}

void GraphicsEnv::setVulkanDeviceExtensions(uint32_t enabledExtensionCount,
                                            const char* const* ppEnabledExtensionNames) {
    ATRACE_CALL();
    if (enabledExtensionCount == 0 || ppEnabledExtensionNames == nullptr) {
        return;
    }

    const uint32_t maxNumStats = android::GpuStatsAppInfo::MAX_NUM_EXTENSIONS;
    uint64_t extensionHashes[maxNumStats];
    const uint32_t numStats = std::min(enabledExtensionCount, maxNumStats);
    for(uint32_t i = 0; i < numStats; i++) {
        extensionHashes[i] = calculateExtensionHash(ppEnabledExtensionNames[i]);
    }
    setTargetStatsArray(android::GpuStatsInfo::Stats::VULKAN_DEVICE_EXTENSION,
                        extensionHashes, numStats);
}

bool GraphicsEnv::readyToSendGpuStatsLocked() {
    // Only send stats for processes having at least one activity launched and that process doesn't
    // skip the GraphicsEnvironment setup.
    return mActivityLaunched && !mGpuStats.appPackageName.empty();
}

void GraphicsEnv::setTargetStats(const GpuStatsInfo::Stats stats, const uint64_t value) {
    return setTargetStatsArray(stats, &value, 1);
}

void GraphicsEnv::setTargetStatsArray(const GpuStatsInfo::Stats stats, const uint64_t* values,
                                      const uint32_t valueCount) {
    ATRACE_CALL();

    std::lock_guard<std::mutex> lock(mStatsLock);
    if (!readyToSendGpuStatsLocked()) return;

    const sp<IGpuService> gpuService = getGpuService();
    if (gpuService) {
        gpuService->setTargetStatsArray(mGpuStats.appPackageName, mGpuStats.driverVersionCode,
                                        stats, values, valueCount);
    }
}

void GraphicsEnv::sendGpuStatsLocked(GpuStatsInfo::Api api, bool isDriverLoaded,
                                     int64_t driverLoadingTime) {
    ATRACE_CALL();

    if (!readyToSendGpuStatsLocked()) return;

    ALOGV("sendGpuStats:\n"
          "\tdriverPackageName[%s]\n"
          "\tdriverVersionName[%s]\n"
          "\tdriverVersionCode[%" PRIu64 "]\n"
          "\tdriverBuildTime[%" PRId64 "]\n"
          "\tappPackageName[%s]\n"
          "\tvulkanVersion[%d]\n"
          "\tapi[%d]\n"
          "\tisDriverLoaded[%d]\n"
          "\tdriverLoadingTime[%" PRId64 "]",
          mGpuStats.driverPackageName.c_str(), mGpuStats.driverVersionName.c_str(),
          mGpuStats.driverVersionCode, mGpuStats.driverBuildTime, mGpuStats.appPackageName.c_str(),
          mGpuStats.vulkanVersion, static_cast<int32_t>(api), isDriverLoaded, driverLoadingTime);

    GpuStatsInfo::Driver driver = GpuStatsInfo::Driver::NONE;
    bool isIntendedDriverLoaded = false;
    if (api == GpuStatsInfo::Api::API_GL) {
        driver = mGpuStats.glDriverToLoad;
        isIntendedDriverLoaded =
                isDriverLoaded && (mGpuStats.glDriverFallback == GpuStatsInfo::Driver::NONE);
    } else {
        driver = mGpuStats.vkDriverToLoad;
        isIntendedDriverLoaded =
                isDriverLoaded && (mGpuStats.vkDriverFallback == GpuStatsInfo::Driver::NONE);
    }

    const sp<IGpuService> gpuService = getGpuService();
    if (gpuService) {
        gpuService->setGpuStats(mGpuStats.driverPackageName, mGpuStats.driverVersionName,
                                mGpuStats.driverVersionCode, mGpuStats.driverBuildTime,
                                mGpuStats.appPackageName, mGpuStats.vulkanVersion, driver,
                                isIntendedDriverLoaded, driverLoadingTime);
    }
}

bool GraphicsEnv::setInjectLayersPrSetDumpable() {
    if (prctl(PR_SET_DUMPABLE, 1, 0, 0, 0) == -1) {
        return false;
    }
    return true;
}

/**
 * APIs for ANGLE
 */

bool GraphicsEnv::shouldUseAngle() {
    // Make sure we are init'ed
    if (mPackageName.empty()) {
        ALOGV("Package name is empty. setAngleInfo() has not been called to enable ANGLE.");
        return false;
    }

    return mShouldUseAngle;
}

// Set ANGLE information.
// If path is "system", it means system ANGLE must be used for the process.
// If shouldUseNativeDriver is true, it means native GLES drivers must be used for the process.
// If path is set to nonempty and shouldUseNativeDriver is true, ANGLE will be used regardless.
void GraphicsEnv::setAngleInfo(const std::string& path, const bool shouldUseNativeDriver,
                               const std::string& packageName,
                               const std::vector<std::string> eglFeatures) {
    if (mShouldUseAngle) {
        // ANGLE is already set up for this application process, even if the application
        // needs to switch from apk to system or vice versa, the application process must
        // be killed and relaunch so that the loader can properly load ANGLE again.
        // The architecture does not support runtime switch between drivers, so just return.
        ALOGE("ANGLE is already set for %s", packageName.c_str());
        return;
    }

    mAngleEglFeatures = std::move(eglFeatures);
    ALOGV("setting ANGLE path to '%s'", path.c_str());
    mAnglePath = std::move(path);
    ALOGV("setting app package name to '%s'", packageName.c_str());
    mPackageName = std::move(packageName);
    if (mAnglePath == "system") {
        mShouldUseSystemAngle = true;
    }
    if (!mAnglePath.empty()) {
        mShouldUseAngle = true;
    }
    mShouldUseNativeDriver = shouldUseNativeDriver;
}

std::string& GraphicsEnv::getPackageName() {
    return mPackageName;
}

const std::vector<std::string>& GraphicsEnv::getAngleEglFeatures() {
    return mAngleEglFeatures;
}

android_namespace_t* GraphicsEnv::getAngleNamespace() {
    std::lock_guard<std::mutex> lock(mNamespaceMutex);

    if (mAngleNamespace) {
        return mAngleNamespace;
    }

    // If ANGLE path is not set, it means ANGLE should not be used for this process;
    // or if ANGLE path is set and set to use system ANGLE, then a namespace is not needed
    // because:
    //     1) if the default OpenGL ES driver is already ANGLE, then the loader will skip;
    //     2) if the default OpenGL ES driver is native, then there's no symbol conflict;
    //     3) if there's no OpenGL ES driver is preloaded, then there's no symbol conflict.
    if (mAnglePath.empty() || mShouldUseSystemAngle) {
        ALOGV("mAnglePath is empty or use system ANGLE, abort creating ANGLE namespace");
        return nullptr;
    }

    // Construct the search paths for system ANGLE.
    const char* const defaultLibraryPaths =
#if defined(__LP64__)
            "/vendor/lib64/egl:/system/lib64";
#else
            "/vendor/lib/egl:/system/lib";
#endif

    // If the application process will run on top of system ANGLE, construct the namespace
    // with sphal namespace being the parent namespace so that search paths and libraries
    // are properly inherited.
    mAngleNamespace =
            android_create_namespace("ANGLE",
                                     mShouldUseSystemAngle ? defaultLibraryPaths
                                                           : mAnglePath.c_str(), // ld_library_path
                                     mShouldUseSystemAngle
                                             ? defaultLibraryPaths
                                             : mAnglePath.c_str(), // default_library_path
                                     ANDROID_NAMESPACE_TYPE_SHARED_ISOLATED,
                                     nullptr, // permitted_when_isolated_path
                                     mShouldUseSystemAngle ? android_get_exported_namespace("sphal")
                                                           : nullptr); // parent

    ALOGD_IF(!mAngleNamespace, "Could not create ANGLE namespace from default");

    if (!mShouldUseSystemAngle) {
        return mAngleNamespace;
    }

    auto vndkNamespace = android_get_exported_namespace("vndk");
    if (!vndkNamespace) {
        mAngleNamespace = nullptr;
        return mAngleNamespace;
    }

    if (!linkDriverNamespaceLocked(mAngleNamespace, vndkNamespace, "")) {
        mAngleNamespace = nullptr;
    }

    return mAngleNamespace;
}

void GraphicsEnv::nativeToggleAngleAsSystemDriver(bool enabled) {
    const sp<IGpuService> gpuService = getGpuService();
    if (!gpuService) {
        ALOGE("No GPU service");
        return;
    }
    gpuService->toggleAngleAsSystemDriver(enabled);
}

bool GraphicsEnv::shouldUseSystemAngle() {
    return mShouldUseSystemAngle;
}

bool GraphicsEnv::shouldUseNativeDriver() {
    return mShouldUseNativeDriver;
}

/**
 * APIs for debuggable layers
 */

void GraphicsEnv::setLayerPaths(NativeLoaderNamespace* appNamespace,
                                const std::string& layerPaths) {
    if (mLayerPaths.empty()) {
        mLayerPaths = layerPaths;
        mAppNamespace = appNamespace;
    } else {
        ALOGV("Vulkan layer search path already set, not clobbering with '%s' for namespace %p'",
              layerPaths.c_str(), appNamespace);
    }
}

NativeLoaderNamespace* GraphicsEnv::getAppNamespace() {
    return mAppNamespace;
}

const std::string& GraphicsEnv::getLayerPaths() {
    return mLayerPaths;
}

const std::string& GraphicsEnv::getDebugLayers() {
    return mDebugLayers;
}

const std::string& GraphicsEnv::getDebugLayersGLES() {
    return mDebugLayersGLES;
}

void GraphicsEnv::setDebugLayers(const std::string& layers) {
    mDebugLayers = layers;
}

void GraphicsEnv::setDebugLayersGLES(const std::string& layers) {
    mDebugLayersGLES = layers;
}

} // namespace android