implement ffi/cpython/pystate

src/ffi/ceval.rs

@@ -2,10 +2,6 @@ use crate::ffi::object::PyObject;
 use crate::ffi::pystate::PyThreadState;
 use std::os::raw::{c_char, c_int, c_void};
 
-// TODO: move to cpython
-pub type _PyFrameEvalFunction =
-    extern "C" fn(*mut crate::ffi::PyFrameObject, c_int) -> *mut PyObject;
-
 extern "C" {
     #[cfg_attr(Py_3_9, deprecated(note = "Python 3.9"))]
     #[cfg_attr(PyPy, link_name = "PyPyEval_CallObjectWithKeywords")]

src/ffi/cpython/ceval.rs

@@ -1,13 +1,16 @@
 use crate::ffi::object::{freefunc, PyObject};
-use crate::ffi::pystate::Py_tracefunc;
+use crate::ffi::Py_tracefunc;
+
 use std::os::raw::c_int;
 
 extern "C" {
+    pub fn PyEval_SetProfile(trace_func: Py_tracefunc, arg1: *mut PyObject);
+
     pub fn _PyEval_EvalFrameDefault(
         arg1: *mut crate::ffi::PyFrameObject,
         exc: c_int,
     ) -> *mut PyObject;
     pub fn _PyEval_RequestCodeExtraIndex(func: freefunc) -> c_int;
-    pub fn PyEval_SetProfile(trace_func: Py_tracefunc, arg1: *mut PyObject);
+
     pub fn PyEval_SetTrace(trace_func: Py_tracefunc, arg1: *mut PyObject);
 }

src/ffi/cpython/mod.rs

@@ -1,23 +1,26 @@
-pub mod abstract_;
+pub(crate) mod abstract_;
 // skipped bytearrayobject.h
 #[cfg(not(PyPy))]
-pub mod bytesobject;
-pub mod ceval;
-pub mod code;
-pub mod compile;
+pub(crate) mod bytesobject;
+pub(crate) mod ceval;
+pub(crate) mod code;
+pub(crate) mod compile;
 #[cfg(not(PyPy))]
-pub mod dictobject;
+pub(crate) mod dictobject;
 // skipped fileobject.h
-pub mod frameobject;
-pub mod import;
+pub(crate) mod frameobject;
+pub(crate) mod import;
 #[cfg(all(Py_3_8, not(PyPy)))]
-pub mod initconfig;
+pub(crate) mod initconfig;
 // skipped interpreteridobject.h
-pub mod listobject;
-pub mod object;
-pub mod pydebug;
+pub(crate) mod listobject;
+pub(crate) mod object;
+pub(crate) mod pydebug;
 #[cfg(all(Py_3_8, not(PyPy)))]
-pub mod pylifecycle;
+pub(crate) mod pylifecycle;
+
+#[cfg(all(Py_3_8, not(PyPy)))]
+pub(crate) mod pystate;
 
 pub use self::abstract_::*;
 #[cfg(not(PyPy))]
@@ -36,3 +39,6 @@ pub use self::object::*;
 pub use self::pydebug::*;
 #[cfg(all(Py_3_8, not(PyPy)))]
 pub use self::pylifecycle::*;
+
+#[cfg(all(Py_3_8, not(PyPy)))]
+pub use self::pystate::*;

src/ffi/cpython/pystate.rs

@@ -0,0 +1,46 @@
+use crate::ffi::pystate::{PyInterpreterState, PyThreadState};
+use std::os::raw::c_int;
+
+// Py_tracefunc is defined in ffi::pystate
+
+pub const PyTrace_CALL: c_int = 0;
+pub const PyTrace_EXCEPTION: c_int = 1;
+pub const PyTrace_LINE: c_int = 2;
+pub const PyTrace_RETURN: c_int = 3;
+pub const PyTrace_C_CALL: c_int = 4;
+pub const PyTrace_C_EXCEPTION: c_int = 5;
+pub const PyTrace_C_RETURN: c_int = 6;
+pub const PyTrace_OPCODE: c_int = 7;
+
+extern "C" {
+    // PyGILState_Check is defined in ffi::pystate
+    pub fn PyInterpreterState_Main() -> *mut PyInterpreterState;
+    pub fn PyInterpreterState_Head() -> *mut PyInterpreterState;
+    pub fn PyInterpreterState_Next(interp: *mut PyInterpreterState) -> *mut PyInterpreterState;
+    pub fn PyInterpreterState_ThreadHead(interp: *mut PyInterpreterState) -> *mut PyThreadState;
+    pub fn PyThreadState_Next(tstate: *mut PyThreadState) -> *mut PyThreadState;
+}
+
+#[cfg(Py_3_9)]
+#[cfg_attr(docsrs, doc(cfg(Py_3_9)))]
+pub type _PyFrameEvalFunction = extern "C" fn(
+    *mut crate::ffi::PyThreadState,
+    *mut crate::ffi::PyFrameObject,
+    c_int,
+) -> *mut crate::ffi::object::PyObject;
+
+#[cfg(Py_3_9)]
+extern "C" {
+    /// Get the frame evaluation function.
+    #[cfg_attr(docsrs, doc(cfg(Py_3_9)))]
+    pub fn _PyInterpreterState_GetEvalFrameFunc(
+        interp: *mut PyInterpreterState,
+    ) -> _PyFrameEvalFunction;
+
+    ///Set the frame evaluation function.
+    #[cfg_attr(docsrs, doc(cfg(Py_3_9)))]
+    pub fn _PyInterpreterState_SetEvalFrameFunc(
+        interp: *mut PyInterpreterState,
+        eval_frame: _PyFrameEvalFunction,
+    );
+}

src/ffi/mod.rs

@@ -1,4 +1,19 @@
-//! Raw ffi declarations for the C interface of Python.
+//! Raw FFI declarations for Python's C API.
+//!
+//! This module provides low level bindings to the Python interpreter.
+//! It is meant for advanced users only - regular PyO3 users shouldn't
+//! need to interact with this module at all.
+//!
+//! # Safety
+//!
+//! The functions in this module lack individual safety documentation, but
+//! generally the following apply:
+//! - Pointer arguments have to point to a valid Python object of the correct type,
+//! although null pointers are sometimes valid input.
+//! - The vast majority can only be used safely while the GIL is held.
+//! - Some functions have additional safety requirements, consult the
+//! [Python/C API Reference Manual](https://docs.python.org/3/c-api/index.html)
+//! for more information.
 #![allow(
     non_camel_case_types,
     non_snake_case,
@@ -27,6 +42,7 @@ pub use self::code::*;
 pub use self::codecs::*;
 pub use self::compile::*;
 pub use self::complexobject::*;
+#[cfg(all(Py_3_8, not(Py_LIMITED_API)))]
 pub use self::context::*;
 #[cfg(not(Py_LIMITED_API))]
 pub use self::datetime::*;
@@ -78,6 +94,7 @@ pub use self::weakrefobject::*;
 
 #[cfg(not(Py_LIMITED_API))]
 pub use self::cpython::*;
+
 mod abstract_;
 // skipped asdl.h
 // skipped ast.h
@@ -95,8 +112,6 @@ mod compile; // TODO: incomplete
 mod complexobject; // TODO supports PEP-384 only
 #[cfg(all(Py_3_8, not(Py_LIMITED_API)))]
 mod context; // It's actually 3.7.1, but no cfg for patches.
-#[cfg(not(all(Py_3_8, not(Py_LIMITED_API))))]
-mod context {}
 #[cfg(not(Py_LIMITED_API))]
 pub(crate) mod datetime;
 mod descrobject; // TODO supports PEP-384 only

src/ffi/pystate.rs

@@ -1,4 +1,5 @@
-use crate::ffi::ceval::_PyFrameEvalFunction;
+#[cfg(all(Py_3_9, not(Py_LIMITED_API)))]
+use crate::ffi::cpython::pystate::_PyFrameEvalFunction;
 use crate::ffi::moduleobject::PyModuleDef;
 use crate::ffi::object::PyObject;
 use crate::ffi::PyFrameObject;
@@ -7,10 +8,29 @@ use std::os::raw::{c_int, c_long};
 pub const MAX_CO_EXTRA_USERS: c_int = 255;
 
 #[repr(C)]
-#[derive(Copy, Clone)]
+#[derive(Debug, Copy, Clone)]
 pub struct PyInterpreterState {
+    /// Not actually a public field
     pub ob_base: PyObject,
+
+    /// Not actually a public field
+    /// Also, it has an additional argument in 3.9
+    #[cfg(not(Py_3_9))]
+    pub eval_frame: extern "C" fn(*mut crate::ffi::PyFrameObject, c_int) -> *mut PyObject,
+
+    /// Not actually a public field
+    /// Also, it has an additional argument in 3.9
+    #[cfg(all(Py_3_9, not(Py_LIMITED_API)))]
     pub eval_frame: _PyFrameEvalFunction,
+
+    /// Not actually a public field
+    /// Also, it has an additional argument in 3.9
+    #[cfg(all(Py_3_9, Py_LIMITED_API))]
+    pub eval_frame: extern "C" fn(
+        *mut crate::ffi::PyThreadState,
+        *mut crate::ffi::PyFrameObject,
+        c_int,
+    ) -> *mut PyObject,
 }
 
 #[repr(C)]