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|
#![cfg(feature = "macros")]
#![cfg(any(not(Py_LIMITED_API), Py_3_11))]
#![warn(unsafe_op_in_unsafe_fn)]
use pyo3::buffer::PyBuffer;
use pyo3::exceptions::PyBufferError;
use pyo3::ffi;
use pyo3::prelude::*;
use pyo3::types::IntoPyDict;
use std::ffi::CString;
use std::ffi::{c_int, c_void};
use std::ptr;
use std::sync::atomic::{AtomicBool, Ordering};
use std::sync::Arc;
mod test_utils;
#[pyclass]
struct TestBufferClass {
vec: Vec<u8>,
drop_called: Arc<AtomicBool>,
}
#[pymethods]
impl TestBufferClass {
unsafe fn __getbuffer__(
slf: Bound<'_, Self>,
view: *mut ffi::Py_buffer,
flags: c_int,
) -> PyResult<()> {
unsafe { fill_view_from_readonly_data(view, flags, &slf.borrow().vec, slf.into_any()) }
}
unsafe fn __releasebuffer__(&self, view: *mut ffi::Py_buffer) {
// Release memory held by the format string
drop(unsafe { CString::from_raw((*view).format) });
}
}
impl Drop for TestBufferClass {
fn drop(&mut self) {
print!("dropped");
self.drop_called.store(true, Ordering::Relaxed);
}
}
#[test]
fn test_buffer() {
let drop_called = Arc::new(AtomicBool::new(false));
Python::attach(|py| {
let instance = Py::new(
py,
TestBufferClass {
vec: vec![b' ', b'2', b'3'],
drop_called: drop_called.clone(),
},
)
.unwrap();
let env = [("ob", instance)].into_py_dict(py).unwrap();
py_assert!(py, *env, "bytes(ob) == b' 23'");
});
assert!(drop_called.load(Ordering::Relaxed));
}
#[test]
fn test_buffer_referenced() {
let drop_called = Arc::new(AtomicBool::new(false));
let buf = {
let input = vec![b' ', b'2', b'3'];
Python::attach(|py| {
let instance = TestBufferClass {
vec: input.clone(),
drop_called: drop_called.clone(),
}
.into_pyobject(py)
.unwrap();
let buf = PyBuffer::<u8>::get(&instance).unwrap();
assert_eq!(buf.to_vec(py).unwrap(), input);
drop(instance);
buf
})
};
assert!(!drop_called.load(Ordering::Relaxed));
Python::attach(|_| {
drop(buf);
});
assert!(drop_called.load(Ordering::Relaxed));
}
#[test]
#[cfg(Py_3_8)] // sys.unraisablehook not available until Python 3.8
fn test_releasebuffer_unraisable_error() {
use pyo3::exceptions::PyValueError;
use test_utils::UnraisableCapture;
#[pyclass]
struct ReleaseBufferError {}
#[pymethods]
impl ReleaseBufferError {
unsafe fn __getbuffer__(
slf: Bound<'_, Self>,
view: *mut ffi::Py_buffer,
flags: c_int,
) -> PyResult<()> {
static BUF_BYTES: &[u8] = b"hello world";
unsafe { fill_view_from_readonly_data(view, flags, BUF_BYTES, slf.into_any()) }
}
unsafe fn __releasebuffer__(&self, _view: *mut ffi::Py_buffer) -> PyResult<()> {
Err(PyValueError::new_err("oh dear"))
}
}
Python::attach(|py| {
let instance = Py::new(py, ReleaseBufferError {}).unwrap();
let (err, object) = UnraisableCapture::enter(py, |capture| {
let env = [("ob", instance.clone_ref(py))].into_py_dict(py).unwrap();
assert!(capture.take_capture().is_none());
py_assert!(py, *env, "bytes(ob) == b'hello world'");
capture.take_capture().unwrap()
});
assert_eq!(err.to_string(), "ValueError: oh dear");
assert!(object.is(&instance));
});
}
/// # Safety
///
/// `view` must be a valid pointer to ffi::Py_buffer, or null
/// `data` must outlive the Python lifetime of `owner` (i.e. data must be owned by owner, or data
/// must be static data)
unsafe fn fill_view_from_readonly_data(
view: *mut ffi::Py_buffer,
flags: c_int,
data: &[u8],
owner: Bound<'_, PyAny>,
) -> PyResult<()> {
if view.is_null() {
return Err(PyBufferError::new_err("View is null"));
}
if (flags & ffi::PyBUF_WRITABLE) == ffi::PyBUF_WRITABLE {
return Err(PyBufferError::new_err("Object is not writable"));
}
unsafe {
(*view).obj = owner.into_ptr();
(*view).buf = data.as_ptr() as *mut c_void;
(*view).len = data.len() as isize;
(*view).readonly = 1;
(*view).itemsize = 1;
(*view).format = if (flags & ffi::PyBUF_FORMAT) == ffi::PyBUF_FORMAT {
let msg = CString::new("B").unwrap();
msg.into_raw()
} else {
ptr::null_mut()
};
(*view).ndim = 1;
(*view).shape = if (flags & ffi::PyBUF_ND) == ffi::PyBUF_ND {
&mut (*view).len
} else {
ptr::null_mut()
};
(*view).strides = if (flags & ffi::PyBUF_STRIDES) == ffi::PyBUF_STRIDES {
&mut (*view).itemsize
} else {
ptr::null_mut()
};
(*view).suboffsets = ptr::null_mut();
(*view).internal = ptr::null_mut();
}
Ok(())
}
|
