79 lines
2 KiB
Rust
79 lines
2 KiB
Rust
use pyo3::class::PyBufferProtocol;
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use pyo3::exceptions::BufferError;
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use pyo3::ffi;
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use pyo3::prelude::*;
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use pyo3::types::IntoPyDict;
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use std::ffi::CStr;
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use std::os::raw::{c_int, c_void};
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use std::ptr;
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#[pyclass]
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struct TestClass {
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vec: Vec<u8>,
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}
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#[pyproto]
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impl PyBufferProtocol for TestClass {
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fn bf_getbuffer(&self, view: *mut ffi::Py_buffer, flags: c_int) -> PyResult<()> {
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if view.is_null() {
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return Err(BufferError::py_err("View is null"));
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}
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unsafe {
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(*view).obj = ptr::null_mut();
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}
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if (flags & ffi::PyBUF_WRITABLE) == ffi::PyBUF_WRITABLE {
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return Err(BufferError::py_err("Object is not writable"));
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}
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let bytes = &self.vec;
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unsafe {
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(*view).buf = bytes.as_ptr() as *mut c_void;
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(*view).len = bytes.len() as isize;
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(*view).readonly = 1;
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(*view).itemsize = 1;
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(*view).format = ptr::null_mut();
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if (flags & ffi::PyBUF_FORMAT) == ffi::PyBUF_FORMAT {
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let msg = CStr::from_bytes_with_nul(b"B\0").unwrap();
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(*view).format = msg.as_ptr() as *mut _;
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}
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(*view).ndim = 1;
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(*view).shape = ptr::null_mut();
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if (flags & ffi::PyBUF_ND) == ffi::PyBUF_ND {
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(*view).shape = (&((*view).len)) as *const _ as *mut _;
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}
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(*view).strides = ptr::null_mut();
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if (flags & ffi::PyBUF_STRIDES) == ffi::PyBUF_STRIDES {
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(*view).strides = &((*view).itemsize) as *const _ as *mut _;
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}
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(*view).suboffsets = ptr::null_mut();
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(*view).internal = ptr::null_mut();
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}
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Ok(())
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}
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}
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#[test]
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fn test_buffer() {
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let gil = Python::acquire_gil();
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let py = gil.python();
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let t = Py::new(
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py,
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TestClass {
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vec: vec![b' ', b'2', b'3'],
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},
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)
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.unwrap();
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let d = [("ob", t)].into_py_dict(py);
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py.run("assert bytes(ob) == b' 23'", None, Some(d)).unwrap();
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}
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