Attempting to fix Python bindings

Author: michaelbautin

hnswlib/hnswlib.h

@@ -491,6 +491,17 @@ class ChunkedArray {
         }
     }
 
+    void copyTo(char* destination, size_t num_bytes) {
+        size_t chunk_index = 0;
+        size_t bytes_per_chunk = getSizePerChunk();
+        while (num_bytes > 0) {
+            size_t cur_size = std::min(bytes_per_chunk, num_bytes);
+            memcpy(destination, chunks_[chunk_index].get(), cur_size);
+            num_bytes -= cur_size;
+            destination += cur_size;
+        }
+    }
+
  private:
     size_t getChunkCount(size_t element_count) const {
         return (element_count + elements_per_chunk_ - 1) / elements_per_chunk_;

python_bindings/bindings.cpp

@@ -383,7 +383,7 @@ class Index {
 
         memset(link_list_npy, 0, link_npy_size);
 
-        memcpy(data_level0_npy, appr_alg->data_level0_memory_, level0_npy_size);
+        appr_alg->data_level0_memory_.copyTo(data_level0_npy, level0_npy_size);
         memcpy(element_levels_npy, appr_alg->element_levels_.data(), appr_alg->element_levels_.size() * sizeof(int));
 
         for (size_t i = 0; i < appr_alg->cur_element_count; i++) {