setTo method

Implementation

void setTo(Object src) {
  Uint8List bytes = _convertObjectToBytes(src);
  int size = bytes.length;

  // String tensors require buffer reallocation because the pre-allocated
  // buffer size does not match the encoded string data size. The native
  // copy path is kept here because the data pointer moves on realloc.
  if (type == TensorType.string) {
    final reallocStatus = tfliteBinding.TfLiteTensorRealloc(size, _tensor);
    if (reallocStatus != TfLiteStatus.kTfLiteOk) {
      throw StateError(
        'TfLiteTensorRealloc failed for string tensor '
        '(requested $size bytes) with '
        'TfLiteStatus=${describeTfLiteStatus(reallocStatus)}.',
      );
    }
    final ptr = calloc<Uint8>(size);
    checkState(isNotNull(ptr), message: 'unallocated');
    ptr.asTypedList(size).setRange(0, size, bytes);
    try {
      final copyStatus = tfliteBinding.TfLiteTensorCopyFromBuffer(
        _tensor,
        ptr.cast(),
        size,
      );
      if (copyStatus != TfLiteStatus.kTfLiteOk) {
        throw StateError(
          'TfLiteTensorCopyFromBuffer failed '
          '(buffer=$size bytes, tensor=${numBytes()} bytes) with '
          'TfLiteStatus=${describeTfLiteStatus(copyStatus)}.',
        );
      }
    } finally {
      calloc.free(ptr);
    }
    return;
  }

  // Single memcpy straight into the tensor's buffer; no native scratch copy.
  // Plain if+throw instead of checkState: quiver builds the interpolated
  // message eagerly, on every successful call in the hot path.
  final tensorByteSize = tfliteBinding.TfLiteTensorByteSize(_tensor);
  if (tensorByteSize != size) {
    throw StateError(
      'TfLiteTensorCopyFromBuffer failed '
      '(buffer=$size bytes, tensor=$tensorByteSize bytes).',
    );
  }
  final data = cast<Uint8>(tfliteBinding.TfLiteTensorData(_tensor));
  checkState(isNotNull(data), message: 'Tensor data is null.');
  data.asTypedList(tensorByteSize).setRange(0, tensorByteSize, bytes);
}