Fix the int32 overflow when computing page fragment sizes for large s…

…tring columns (#16028)

This PR fixes the possible `int32` overflow when computing page fragment sizes for large (2B+ char) string columns.

Authors:
  - Muhammad Haseeb (https://github.com/mhaseeb123)

Approvers:
  - Vukasin Milovanovic (https://github.com/vuule)
  - Nghia Truong (https://github.com/ttnghia)

URL: #16028

cpp/src/io/parquet/writer_impl.cu

@@ -1763,10 +1763,10 @@ auto convert_table_to_parquet_data(table_input_metadata& table_meta,
     // for multiple fragments per page to smooth things out. using 2 was too
     // unbalanced in final page sizes, so using 4 which seems to be a good
     // compromise at smoothing things out without getting fragment sizes too small.
-    auto frag_size_fn = [&](auto const& col, size_type col_size) {
+    auto frag_size_fn = [&](auto const& col, size_t col_size) {
       int const target_frags_per_page = is_col_fixed_width(col) ? 1 : 4;
       auto const avg_len =
-        target_frags_per_page * util::div_rounding_up_safe<size_type>(col_size, input.num_rows());
+        target_frags_per_page * util::div_rounding_up_safe<size_t>(col_size, input.num_rows());
       if (avg_len > 0) {
         auto const frag_size = util::div_rounding_up_safe<size_type>(max_page_size_bytes, avg_len);
         return std::min<size_type>(max_page_fragment_size, frag_size);