Fix a ClassNotFoundException crash on app start

This is equivalent to e6034a4740756334317ab2445b518a645930f4f4 in
qtbase, and needed because of a bug on Android that causes JNI_OnLoad()
to be called multiple times for the same library.

Fixes: QTBUG-80995
Change-Id: I86686feeb30f13cf56ea13c98bed3d5b799dfd90
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@qt.io>

1 files changed, 13 insertions, 5 deletions

diff --git a/src/purchasing/inapppurchase/android/qandroidjni.cpp b/src/purchasing/inapppurchase/android/qandroidjni.cpp
index 3c4d700..d1f4920 100644
--- a/src/purchasing/inapppurchase/android/qandroidjni.cpp
+++ b/src/purchasing/inapppurchase/android/qandroidjni.cpp
@@ -119,15 +119,23 @@ static JNINativeMethod methods[] = {
     {"purchaseFailed", "(JIILjava/lang/String;)V", (void *)purchaseFailed}
 };
 
-jint JNICALL JNI_OnLoad(JavaVM *vm, void *)
+JNIEXPORT jint JNICALL JNI_OnLoad(JavaVM *vm, void *)
 {
+    static bool initialized = false;
+    if (initialized)
+        return JNI_VERSION_1_6;
+    initialized = true;
+
     JNIEnv *env;
-    if (vm->GetEnv(reinterpret_cast<void **>(&env), JNI_VERSION_1_4) != JNI_OK)
-        return JNI_FALSE;
+    if (vm->GetEnv(reinterpret_cast<void **>(&env), JNI_VERSION_1_6) != JNI_OK)
+        return JNI_ERR;
 
     jclass clazz = env->FindClass("org/qtproject/qt5/android/purchasing/QtInAppPurchase");
+    if (!clazz)
+        return JNI_ERR;
+
     if (env->RegisterNatives(clazz, methods, sizeof(methods) / sizeof(methods[0])) < 0)
-        return JNI_FALSE;
+        return JNI_ERR;
 
-    return JNI_VERSION_1_4;
+    return JNI_VERSION_1_6;
 }