polars_arrow/ffi/
mod.rs

1#![allow(unsafe_op_in_unsafe_fn)]
2//! contains FFI bindings to import and export [`Array`](crate::array::Array) via
3//! Arrow's [C Data Interface](https://arrow.apache.org/docs/format/CDataInterface.html)
4mod array;
5mod bridge;
6mod generated;
7pub mod mmap;
8mod schema;
9mod stream;
10
11pub(crate) use array::{ArrowArrayRef, InternalArrowArray, try_from};
12pub(crate) use bridge::align_to_c_data_interface;
13pub use generated::{ArrowArray, ArrowArrayStream, ArrowSchema};
14use polars_error::PolarsResult;
15pub use stream::{ArrowArrayStreamReader, export_iterator};
16
17use self::schema::to_field;
18use crate::array::Array;
19use crate::datatypes::{ArrowDataType, Field};
20
21/// Exports an [`Box<dyn Array>`] to the C data interface.
22pub fn export_array_to_c(array: Box<dyn Array>) -> ArrowArray {
23    ArrowArray::new(bridge::align_to_c_data_interface(array))
24}
25
26/// Exports a [`Field`] to the C data interface.
27pub fn export_field_to_c(field: &Field) -> ArrowSchema {
28    ArrowSchema::new(field)
29}
30
31/// Imports a [`Field`] from the C data interface.
32/// # Safety
33/// This function is intrinsically `unsafe` and relies on a [`ArrowSchema`]
34/// being valid according to the [C data interface](https://arrow.apache.org/docs/format/CDataInterface.html) (FFI).
35pub unsafe fn import_field_from_c(field: &ArrowSchema) -> PolarsResult<Field> {
36    to_field(field)
37}
38
39/// Imports an [`Array`] from the C data interface.
40/// # Safety
41/// This function is intrinsically `unsafe` and relies on a [`ArrowArray`]
42/// being valid according to the [C data interface](https://arrow.apache.org/docs/format/CDataInterface.html) (FFI).
43pub unsafe fn import_array_from_c(
44    array: ArrowArray,
45    dtype: ArrowDataType,
46) -> PolarsResult<Box<dyn Array>> {
47    try_from(InternalArrowArray::new(array, dtype))
48}
polars_arrow/ffi/mod.rs

polars_arrow/ffi/
mod.rs
