path: root/src/corelib/kernel/qcoreapplication_android.cpp

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#include "qcoreapplication.h"
#include "qcoreapplication_p.h"

#include <QtCore/private/qjnihelpers_p.h>
#include <QtCore/qfuture.h>
#include <QtCore/qjnienvironment.h>
#include <QtCore/qjniobject.h>
#include <QtCore/qlist.h>
#include <QtCore/qmutex.h>
#include <QtCore/qpromise.h>
#include <QtCore/qscopedpointer.h>

QT_BEGIN_NAMESPACE

static const char qtNativeClassName[] = "org/qtproject/qt/android/QtNative";

#ifndef QT_NO_EXCEPTIONS
static const char emptyPermissionExcept[] = "The permission cannot be an empty string.";
static const char invalidNativePermissionExcept[] =
        "Coudn't convert the provided permission type to a native Android permission string.";
#endif

QPermission::PermissionResult resultFromAndroid(jint value)
{
    return value == 0 ? QPermission::Authorized : QPermission::Denied;
}

using PendingPermissionRequestsHash
            = QHash<int, QSharedPointer<QPromise<QPermission::PermissionResult>>>;
Q_GLOBAL_STATIC(PendingPermissionRequestsHash, g_pendingPermissionRequests);
static QBasicMutex g_pendingPermissionRequestsMutex;

static int nextRequestCode()
{
    static QBasicAtomicInt counter = Q_BASIC_ATOMIC_INITIALIZER(0);
    return counter.fetchAndAddRelaxed(1);
}

static QStringList nativeStringsFromPermission(QPermission::PermisionType permission)
{
    static const auto precisePerm = QStringLiteral("android.permission.ACCESS_FINE_LOCATION");
    static const auto coarsePerm = QStringLiteral("android.permission.ACCESS_COARSE_LOCATION");
    static const auto backgroundPerm =
            QStringLiteral("android.permission.ACCESS_BACKGROUND_LOCATION");

    switch (permission) {
    case QPermission::CoarseLocation:
        return {coarsePerm};
    case QPermission::PreciseLocation:
        return {precisePerm};
    case QPermission::CoarseBackgroundLocation:
        // Keep the background permission first to be able to use .first()
        // in checkPermission because it takes single permission
        if (QtAndroidPrivate::androidSdkVersion() >= 29)
            return {backgroundPerm, coarsePerm};
        return {coarsePerm};
    case QPermission::PreciseBackgroundLocation:
        if (QtAndroidPrivate::androidSdkVersion() >= 29)
            return {backgroundPerm, precisePerm};
        return {precisePerm};
    case QPermission::Camera:
        return {QStringLiteral("android.permission.CAMERA")};
    case QPermission::Microphone:
        return {QStringLiteral("android.permission.RECORD_AUDIO")};
    case QPermission::BodySensors:
        return {QStringLiteral("android.permission.BODY_SENSORS")};
    case QPermission::PhysicalActivity:
        return {QStringLiteral("android.permission.ACTIVITY_RECOGNITION")};
    case QPermission::ReadContacts:
        return {QStringLiteral("android.permission.READ_CONTACTS")};
    case QPermission::WriteContacts:
        return {QStringLiteral("android.permission.WRITE_CONTACTS")};
    case QPermission::ReadStorage:
        return {QStringLiteral("android.permission.READ_EXTERNAL_STORAGE")};
    case QPermission::WriteStorage:
        return {QStringLiteral("android.permission.WRITE_EXTERNAL_STORAGE")};
    case QPermission::ReadCalendar:
        return {QStringLiteral("android.permission.READ_CALENDAR")};
    case QPermission::WriteCalendar:
        return {QStringLiteral("android.permission.WRITE_CALENDAR")};

    default:
        return {};
    }
}

/*!
    \internal

    This function is called when the result of the permission request is available.
    Once a permission is requested, the result is braodcast by the OS and listened
    to by QtActivity which passes it to C++ through a native JNI method call.
 */
static void sendRequestPermissionsResult(JNIEnv *env, jobject *obj, jint requestCode,
                                         jobjectArray permissions, jintArray grantResults)
{
    Q_UNUSED(obj);

    QMutexLocker locker(&g_pendingPermissionRequestsMutex);
    auto it = g_pendingPermissionRequests->constFind(requestCode);
    if (it == g_pendingPermissionRequests->constEnd()) {
        qWarning() << "Found no valid pending permission request for request code" << requestCode;
        return;
    }

    auto request = *it;
    g_pendingPermissionRequests->erase(it);
    locker.unlock();

    const int size = env->GetArrayLength(permissions);
    std::unique_ptr<jint[]> results(new jint[size]);
    env->GetIntArrayRegion(grantResults, 0, size, results.get());

    for (int i = 0 ; i < size; ++i) {
        QPermission::PermissionResult result = resultFromAndroid(results[i]);
        request->addResult(result, i);
    }

    request->finish();
}

QFuture<QPermission::PermissionResult> requestPermissionsInternal(const QStringList &permissions)
{
    QSharedPointer<QPromise<QPermission::PermissionResult>> promise;
    promise.reset(new QPromise<QPermission::PermissionResult>());
    QFuture<QPermission::PermissionResult> future = promise->future();
    promise->start();

    // No mechanism to request permission for SDK version below 23, because
    // permissions defined in the manifest are granted at install time.
    if (QtAndroidPrivate::androidSdkVersion() < 23) {
        for (int i = 0; i < permissions.size(); ++i)
            promise->addResult(QCoreApplication::checkPermission(permissions.at(i)).result(), i);
        promise->finish();
        return future;
    }

    const int requestCode = nextRequestCode();
    QMutexLocker locker(&g_pendingPermissionRequestsMutex);
    g_pendingPermissionRequests->insert(requestCode, promise);

    QtAndroidPrivate::runOnAndroidThread([permissions, requestCode] {
        QJniEnvironment env;
        jclass clazz = env.findClass("java/lang/String");
        auto array = env->NewObjectArray(permissions.size(), clazz, nullptr);
        int index = 0;

        for (auto &perm : permissions)
            env->SetObjectArrayElement(array, index++, QJniObject::fromString(perm).object());

        QJniObject(QtAndroidPrivate::activity()).callMethod<void>("requestPermissions",
                                                                  "([Ljava/lang/String;I)V",
                                                                  array,
                                                                  requestCode);
        env->DeleteLocalRef(array);
    }, QJniEnvironment().jniEnv());

    return future;
}

QFuture<QPermission::PermissionResult>
QCoreApplicationPrivate::requestPermission(const QString &permission)
{
    // avoid the uneccessary call and response to an empty permission string
    if (permission.size() > 0)
        return requestPermissionsInternal({permission});

    QPromise<QPermission::PermissionResult> promise;
    QFuture<QPermission::PermissionResult> future = promise.future();
    promise.start();
#ifndef QT_NO_EXCEPTIONS
    promise.setException(std::make_exception_ptr(std::runtime_error(emptyPermissionExcept)));
#else
    promise.addResult(QPermission::Denied);
#endif
    promise.finish();
    return future;
}

QFuture<QPermission::PermissionResult> groupRequestToSingleResult(const QStringList &permissions)
{
    QSharedPointer<QPromise<QPermission::PermissionResult>> promise;
    promise.reset(new QPromise<QPermission::PermissionResult>());
    QFuture<QPermission::PermissionResult> future = promise->future();
    promise->start();
    requestPermissionsInternal(permissions).then(
                [promise](QFuture<QPermission::PermissionResult> future) {
        auto results = future.results();
        if (results.count(QPermission::Authorized) == results.count())
            promise->addResult(QPermission::Authorized, 0);
        else
            promise->addResult(QPermission::Denied, 0);
        promise->finish();
    });

    return future;
}

QFuture<QPermission::PermissionResult>
QCoreApplicationPrivate::requestPermission(QPermission::PermisionType permission)
{
    const auto nativePermissions = nativeStringsFromPermission(permission);

    if (nativePermissions.size() > 0)
        return groupRequestToSingleResult(nativePermissions);

    QPromise<QPermission::PermissionResult> promise;
    QFuture<QPermission::PermissionResult> future = promise.future();
    promise.start();
#ifndef QT_NO_EXCEPTIONS
    promise.setException(std::make_exception_ptr(
                             std::runtime_error(invalidNativePermissionExcept)));
#else
    promise.addResult(QPermission::Denied);
#endif
    promise.finish();
    return future;
}

QFuture<QPermission::PermissionResult>
QCoreApplicationPrivate::checkPermission(const QString &permission)
{
    QPromise<QPermission::PermissionResult> promise;
    QFuture<QPermission::PermissionResult> future = promise.future();
    promise.start();

    if (permission.size() > 0) {
        auto res = QJniObject::callStaticMethod<jint>(qtNativeClassName,
                                                      "checkSelfPermission",
                                                      "(Ljava/lang/String;)I",
                                                      QJniObject::fromString(permission).object());
        promise.addResult(resultFromAndroid(res));
    } else {
#ifndef QT_NO_EXCEPTIONS
        promise.setException(std::make_exception_ptr(std::runtime_error(emptyPermissionExcept)));
#else
        promise.addResult(QPermission::Denied);
#endif
    }

    promise.finish();
    return future;
}

QFuture<QPermission::PermissionResult>
QCoreApplicationPrivate::checkPermission(QPermission::PermisionType permission)
{
    const auto nativePermissions = nativeStringsFromPermission(permission);

    if (nativePermissions.size() > 0)
        return checkPermission(nativePermissions.first());

    QPromise<QPermission::PermissionResult> promise;
    QFuture<QPermission::PermissionResult> future = promise.future();
    promise.start();
#ifndef QT_NO_EXCEPTIONS
    promise.setException(std::make_exception_ptr(
                             std::runtime_error(invalidNativePermissionExcept)));
#else
    promise.addResult(QPermission::Denied);
#endif
    promise.finish();
    return future;
}

bool QtAndroidPrivate::registerPermissionNatives()
{
    if (QtAndroidPrivate::androidSdkVersion() < 23)
        return true;

    JNINativeMethod methods[] = {
        {"sendRequestPermissionsResult", "(I[Ljava/lang/String;[I)V",
         reinterpret_cast<void *>(sendRequestPermissionsResult)
        }};

    QJniEnvironment env;
    return env.registerNativeMethods(qtNativeClassName, methods, 1);
}

QT_END_NAMESPACE