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19de10d3d8
This ensures the buffers used by the empty `bytearray` and `array.array` are aligned the same as a pointer returned by the allocator. This is a more convenient default for interop with other languages that have stricter requirements of type-safe buffers (e.g. Rust's `&[T]` type) even when empty.
136 lines
3.1 KiB
C
136 lines
3.1 KiB
C
/* Test PEP 688 - Buffers */
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#include "parts.h"
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#include <stddef.h> // offsetof
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typedef struct {
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PyObject_HEAD
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PyObject *obj;
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Py_ssize_t references;
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} testBufObject;
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#define testBufObject_CAST(op) ((testBufObject *)(op))
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static PyObject *
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testbuf_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
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{
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PyObject *obj = PyBytes_FromString("test");
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if (obj == NULL) {
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return NULL;
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}
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testBufObject *self = (testBufObject *)type->tp_alloc(type, 0);
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if (self == NULL) {
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Py_DECREF(obj);
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return NULL;
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}
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self->obj = obj;
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self->references = 0;
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return (PyObject *)self;
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}
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static int
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testbuf_traverse(PyObject *op, visitproc visit, void *arg)
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{
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testBufObject *self = testBufObject_CAST(op);
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Py_VISIT(self->obj);
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return 0;
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}
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static int
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testbuf_clear(PyObject *op)
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{
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testBufObject *self = testBufObject_CAST(op);
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Py_CLEAR(self->obj);
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return 0;
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}
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static void
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testbuf_dealloc(PyObject *op)
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{
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testBufObject *self = testBufObject_CAST(op);
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PyObject_GC_UnTrack(self);
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Py_XDECREF(self->obj);
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Py_TYPE(self)->tp_free(self);
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}
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static int
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testbuf_getbuf(PyObject *op, Py_buffer *view, int flags)
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{
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testBufObject *self = testBufObject_CAST(op);
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int buf = PyObject_GetBuffer(self->obj, view, flags);
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if (buf == 0) {
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Py_SETREF(view->obj, Py_NewRef(self));
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self->references++;
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}
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return buf;
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}
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static void
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testbuf_releasebuf(PyObject *op, Py_buffer *Py_UNUSED(view))
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{
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testBufObject *self = testBufObject_CAST(op);
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self->references--;
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assert(self->references >= 0);
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}
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static PyBufferProcs testbuf_as_buffer = {
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.bf_getbuffer = testbuf_getbuf,
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.bf_releasebuffer = testbuf_releasebuf,
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};
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static struct PyMemberDef testbuf_members[] = {
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{"references", Py_T_PYSSIZET, offsetof(testBufObject, references), Py_READONLY},
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{NULL},
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};
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static PyTypeObject testBufType = {
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PyVarObject_HEAD_INIT(NULL, 0)
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.tp_name = "testBufType",
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.tp_basicsize = sizeof(testBufObject),
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.tp_flags = Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC,
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.tp_new = testbuf_new,
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.tp_dealloc = testbuf_dealloc,
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.tp_traverse = testbuf_traverse,
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.tp_clear = testbuf_clear,
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.tp_as_buffer = &testbuf_as_buffer,
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.tp_members = testbuf_members
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};
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/* Get the pointer from a buffer-supporting object as a PyLong.
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*
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* Used to test alignment properties. */
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static PyObject *
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buffer_pointer_as_int(PyObject *Py_UNUSED(module), PyObject *obj)
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{
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PyObject *out;
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Py_buffer view;
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if (PyObject_GetBuffer(obj, &view, PyBUF_SIMPLE) != 0) {
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return NULL;
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}
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out = PyLong_FromVoidPtr(view.buf);
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PyBuffer_Release(&view);
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return out;
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}
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static PyMethodDef test_methods[] = {
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{"buffer_pointer_as_int", buffer_pointer_as_int, METH_O},
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{NULL},
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};
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int
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_PyTestCapi_Init_Buffer(PyObject *m) {
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if (PyType_Ready(&testBufType) < 0) {
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return -1;
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}
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if (PyModule_AddObjectRef(m, "testBuf", (PyObject *)&testBufType)) {
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return -1;
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}
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if (PyModule_AddFunctions(m, test_methods) < 0) {
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return -1;
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}
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return 0;
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}
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