Copy fbjni library from react-native

lib/fb/jni/ByteBuffer.cpp

@@ -0,0 +1,77 @@
+/*
+ * Copyright (c) 2016-present, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ */
+
+#include <fb/fbjni/ByteBuffer.h>
+
+#include <stdexcept>
+
+#include <fb/fbjni/References.h>
+
+namespace facebook {
+namespace jni {
+
+namespace {
+local_ref<JByteBuffer> createEmpty() {
+  static auto cls = JByteBuffer::javaClassStatic();
+  static auto meth = cls->getStaticMethod<JByteBuffer::javaobject(int)>("allocateDirect");
+  return meth(cls, 0);
+}
+}
+
+local_ref<JByteBuffer> JByteBuffer::wrapBytes(uint8_t* data, size_t size) {
+  // env->NewDirectByteBuffer requires that size is positive. Android's
+  // dalvik returns an invalid result and Android's art aborts if size == 0.
+  // Workaround this by using a slow path through Java in that case.
+  if (!size) {
+    return createEmpty();
+  }
+  auto res = adopt_local(static_cast<javaobject>(Environment::current()->NewDirectByteBuffer(data, size)));
+  FACEBOOK_JNI_THROW_PENDING_EXCEPTION();
+  if (!res) {
+    throw std::runtime_error("Direct byte buffers are unsupported.");
+  }
+  return res;
+}
+
+uint8_t* JByteBuffer::getDirectBytes() {
+  if (!self()) {
+    throwNewJavaException("java/lang/NullPointerException", "java.lang.NullPointerException");
+  }
+  void* bytes = Environment::current()->GetDirectBufferAddress(self());
+  FACEBOOK_JNI_THROW_PENDING_EXCEPTION();
+  if (!bytes) {
+    throw std::runtime_error(
+        isDirect() ?
+          "Attempt to get direct bytes of non-direct byte buffer." :
+          "Error getting direct bytes of byte buffer.");
+  }
+  return static_cast<uint8_t*>(bytes);
+}
+
+size_t JByteBuffer::getDirectSize() {
+  if (!self()) {
+    throwNewJavaException("java/lang/NullPointerException", "java.lang.NullPointerException");
+  }
+  int size = Environment::current()->GetDirectBufferCapacity(self());
+  FACEBOOK_JNI_THROW_PENDING_EXCEPTION();
+  if (size < 0) {
+    throw std::runtime_error(
+        isDirect() ?
+          "Attempt to get direct size of non-direct byte buffer." :
+          "Error getting direct size of byte buffer.");
+  }
+  return static_cast<size_t>(size);
+}
+
+bool JByteBuffer::isDirect() {
+  static auto meth = javaClassStatic()->getMethod<jboolean()>("isDirect");
+  return meth(self());
+}
+
+}}