local_ref<jstring> make_jstring(const char* utf8) {
if (!utf8) {
return {};
}
const auto env = internal::getEnv();
size_t len;
size_t modlen = detail::modifiedLength(reinterpret_cast<const uint8_t*>(utf8), &len);
jstring result;
if (modlen == len) {
// The only difference between utf8 and modifiedUTF8 is in encoding 4-byte UTF8 chars
// and '\0' that is encoded on 2 bytes.
//
// Since modifiedUTF8-encoded string can be no shorter than it's UTF8 conterpart we
// know that if those two strings are of the same length we don't need to do any
// conversion -> no 4-byte chars nor '\0'.
result = env->NewStringUTF(utf8);
} else {
auto modified = std::vector<char>(modlen + 1); // allocate extra byte for \0
detail::utf8ToModifiedUTF8(
reinterpret_cast<const uint8_t*>(utf8), len,
reinterpret_cast<uint8_t*>(modified.data()), modified.size());
result = env->NewStringUTF(modified.data());
}
FACEBOOK_JNI_THROW_PENDING_EXCEPTION();
return adopt_local(result);
}
size_t JByteBuffer::getDirectSize() const {
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);
}
uint8_t* JByteBuffer::getDirectBytes() const {
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);
}
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;
}
