Add defensive check for result returned after JNI function calls

Summary:
Added method which checks if value(methodId, fieldId, class ...) returned by JNI functions (getMethod, getField, getClass ...) is valid or not and throw exception if they are not valid

##Changelog:
[Internal][Yoga] Add defensive check for result returned after JNI calls

Reviewed By: astreet

Differential Revision: D18745718

fbshipit-source-id: 2af26eda15fbe7834e1c9b274deeed4f106274ab

java/jni/common.cpp

@@ -18,11 +18,11 @@ void registerNatives(
     size_t numMethods) {
   jclass clazz = env->FindClass(className);
 
-  assertNoPendingJniException(env);
+  assertNoPendingJniExceptionIf(env, !clazz);
 
-  env->RegisterNatives(clazz, methods, numMethods);
+  auto result = env->RegisterNatives(clazz, methods, numMethods);
 
-  assertNoPendingJniException(env);
+  assertNoPendingJniExceptionIf(env, result != JNI_OK);
 }
 
 jmethodID getStaticMethodId(
@@ -32,7 +32,7 @@ jmethodID getStaticMethodId(
     const char* methodDescriptor) {
   jmethodID methodId =
       env->GetStaticMethodID(clazz, methodName, methodDescriptor);
-  assertNoPendingJniException(env);
+  assertNoPendingJniExceptionIf(env, !methodId);
   return methodId;
 }
 
@@ -42,7 +42,7 @@ jmethodID getMethodId(
     const char* methodName,
     const char* methodDescriptor) {
   jmethodID methodId = env->GetMethodID(clazz, methodName, methodDescriptor);
-  assertNoPendingJniException(env);
+  assertNoPendingJniExceptionIf(env, !methodId);
   return methodId;
 }
 
@@ -52,7 +52,7 @@ jfieldID getFieldId(
     const char* fieldName,
     const char* fieldSignature) {
   jfieldID fieldId = env->GetFieldID(clazz, fieldName, fieldSignature);
-  assertNoPendingJniException(env);
+  assertNoPendingJniExceptionIf(env, !fieldId);
   return fieldId;
 }
 
@@ -83,7 +83,7 @@ callStaticObjectMethod(JNIEnv* env, jclass clazz, jmethodID methodId, ...) {
   va_start(args, methodId);
   jobject result = env->CallStaticObjectMethodV(clazz, methodId, args);
   va_end(args);
-  assertNoPendingJniException(env);
+  assertNoPendingJniExceptionIf(env, !result);
   return make_local_ref(env, result);
 }
 

java/jni/corefunctions.cpp

@@ -76,6 +76,19 @@ void assertNoPendingJniException(JNIEnv* env) {
   throw YogaJniException(throwable);
 }
 
+void assertNoPendingJniExceptionIf(JNIEnv* env, bool condition) {
+  if (!condition) {
+    return;
+  }
+
+  if (env->ExceptionCheck() == JNI_TRUE) {
+    assertNoPendingJniException(env);
+    return;
+  }
+
+  throw YogaJniException();
+}
+
 } // namespace vanillajni
 } // namespace yoga
 } // namespace facebook

java/jni/corefunctions.h

@@ -47,6 +47,8 @@ void logErrorMessageAndDie(const char* message);
  */
 void assertNoPendingJniException(JNIEnv* env);
 
+void assertNoPendingJniExceptionIf(JNIEnv* env, bool condition);
+
 } // namespace vanillajni
 } // namespace yoga
 } // namespace facebook