From 4d8959b73ac194ca9a2f623dcb5c23680f7d8536 Mon Sep 17 00:00:00 2001
From: Eric Snow <ericsnowcurrently@gmail.com>
Date: Thu, 16 Feb 2023 14:05:31 -0700
Subject: [PATCH] gh-101758: Add _PyState_AddModule() Back for the Stable ABI
 (gh-101956)

We're adding the function back, only for the stable ABI symbol and not as any form of API. I had removed it yesterday.

This undocumented "private" function was added with the implementation for PEP 3121 (3.0, 2007) for internal use and later moved out of the limited API (3.6, 2016) and then into the internal API (3.9, 2019). I removed it completely yesterday, including from the stable ABI manifest (where it was added because the symbol happened to be exported). It's unlikely that anyone is using _PyState_AddModule(), especially any stable ABI extensions built against 3.2-3.5, but we're playing it safe.

https://github.com/python/cpython/issues/101758
---
 Include/internal/pycore_pystate.h  |  6 ++++++
 Lib/test/test_stable_abi_ctypes.py |  1 +
 Misc/stable_abi.toml               |  3 +++
 PC/python3dll.c                    |  1 +
 Python/import.c                    | 20 ++++++++++++++++++++
 5 files changed, 31 insertions(+)

diff --git a/Include/internal/pycore_pystate.h b/Include/internal/pycore_pystate.h
index 638b86253879ea..7046ec8d9adaaf 100644
--- a/Include/internal/pycore_pystate.h
+++ b/Include/internal/pycore_pystate.h
@@ -152,6 +152,12 @@ extern void _PySignal_AfterFork(void);
 #endif
 
 
+PyAPI_FUNC(int) _PyState_AddModule(
+    PyThreadState *tstate,
+    PyObject* module,
+    PyModuleDef* def);
+
+
 PyAPI_FUNC(int) _PyOS_InterruptOccurred(PyThreadState *tstate);
 
 #define HEAD_LOCK(runtime) \
diff --git a/Lib/test/test_stable_abi_ctypes.py b/Lib/test/test_stable_abi_ctypes.py
index 7e50fbda2c07cb..e77c1c8409880d 100644
--- a/Lib/test/test_stable_abi_ctypes.py
+++ b/Lib/test/test_stable_abi_ctypes.py
@@ -864,6 +864,7 @@ def test_windows_feature_macros(self):
     "_PyObject_GC_Resize",
     "_PyObject_New",
     "_PyObject_NewVar",
+    "_PyState_AddModule",
     "_PyThreadState_Init",
     "_PyThreadState_Prealloc",
     "_PyWeakref_CallableProxyType",
diff --git a/Misc/stable_abi.toml b/Misc/stable_abi.toml
index c04a3a228caf56..21ff9616133445 100644
--- a/Misc/stable_abi.toml
+++ b/Misc/stable_abi.toml
@@ -1684,6 +1684,9 @@
 [function._PyObject_NewVar]
     added = '3.2'
     abi_only = true
+[function._PyState_AddModule]
+    added = '3.2'
+    abi_only = true
 [function._PyThreadState_Init]
     added = '3.2'
     abi_only = true
diff --git a/PC/python3dll.c b/PC/python3dll.c
index 79f09037282f54..e300819365756e 100755
--- a/PC/python3dll.c
+++ b/PC/python3dll.c
@@ -34,6 +34,7 @@ EXPORT_FUNC(_PyObject_GC_NewVar)
 EXPORT_FUNC(_PyObject_GC_Resize)
 EXPORT_FUNC(_PyObject_New)
 EXPORT_FUNC(_PyObject_NewVar)
+EXPORT_FUNC(_PyState_AddModule)
 EXPORT_FUNC(_PyThreadState_Init)
 EXPORT_FUNC(_PyThreadState_Prealloc)
 EXPORT_FUNC(Py_AddPendingCall)
diff --git a/Python/import.c b/Python/import.c
index ec126f28b85816..fabf03b1c5d698 100644
--- a/Python/import.c
+++ b/Python/import.c
@@ -487,6 +487,26 @@ PyState_FindModule(PyModuleDef* module)
     return _modules_by_index_get(interp, module);
 }
 
+/* _PyState_AddModule() has been completely removed from the C-API
+   (and was removed from the limited API in 3.6).  However, we're
+   playing it safe and keeping it around for any stable ABI extensions
+   built against 3.2-3.5. */
+int
+_PyState_AddModule(PyThreadState *tstate, PyObject* module, PyModuleDef* def)
+{
+    if (!def) {
+        assert(_PyErr_Occurred(tstate));
+        return -1;
+    }
+    if (def->m_slots) {
+        _PyErr_SetString(tstate,
+                         PyExc_SystemError,
+                         "PyState_AddModule called on module with slots");
+        return -1;
+    }
+    return _modules_by_index_set(tstate->interp, def, module);
+}
+
 int
 PyState_AddModule(PyObject* module, PyModuleDef* def)
 {