Fix threading in calling PyOS_InputHook from new REPL

Include/pythonrun.h

@@ -17,9 +17,9 @@ PyAPI_FUNC(void) PyErr_Display(PyObject *, PyObject *, PyObject *);
 PyAPI_FUNC(void) PyErr_DisplayException(PyObject *);
 #endif
 
-
 /* Stuff with no proper home (yet) */
 PyAPI_DATA(int) (*PyOS_InputHook)(void);
+PyAPI_FUNC(int) _PyOS_CallInputHook(void);
 
 /* Stack size, in "pointers" (so we get extra safety margins
    on 64-bit platforms).  On a 32-bit platform, this translates

Lib/_pyrepl/reader.py

@@ -24,6 +24,7 @@
 from contextlib import contextmanager
 from dataclasses import dataclass, field, fields
 import unicodedata
+import ctypes
 from _colorize import can_colorize, ANSIColors  # type: ignore[import-not-found]
 
 
@@ -239,6 +240,7 @@ class Reader:
     lxy: tuple[int, int] = field(init=False)
     calc_screen: CalcScreen = field(init=False)
     scheduled_commands: list[str] = field(default_factory=list)
+    input_hook_addr: ctypes.c_void_p | None = None
 
     def __post_init__(self) -> None:
         # Enable the use of `insert` without a `prepare` call - necessary to
@@ -643,6 +645,7 @@ def handle1(self, block: bool = True) -> bool:
             self.dirty = True
 
         while True:
+            ctypes.pythonapi._PyOS_CallInputHook()
             event = self.console.get_event(block)
             if not event:  # can only happen if we're not blocking
                 return False

Lib/test/test_pyrepl/test_reader.py

@@ -1,8 +1,10 @@
 import itertools
 import functools
 from unittest import TestCase
+from unittest.mock import MagicMock
 
 from .support import handle_all_events, handle_events_narrow_console, code_to_events, prepare_reader
+from test.support import import_helper
 from _pyrepl.console import Event
 
 
@@ -176,3 +178,24 @@ def test_newline_within_block_trailing_whitespace(self):
         )
         self.assert_screen_equals(reader, expected)
         self.assertTrue(reader.finished)
+
+    def test_input_hook_is_called_if_set(self):
+        import_helper.import_module('ctypes')
+        from ctypes import pythonapi, c_int, CFUNCTYPE, c_void_p, POINTER, cast
+
+        CMPFUNC = CFUNCTYPE(c_int)
+        the_mock = MagicMock()
+
+        def input_hook():
+            the_mock()
+            return 0
+
+        the_input_hook = CMPFUNC(input_hook)
+        prev_value = c_void_p.in_dll(pythonapi, "PyOS_InputHook").value
+        try:
+            c_void_p.in_dll(pythonapi, "PyOS_InputHook").value =  cast(the_input_hook, c_void_p).value
+            events = code_to_events("a")
+            reader, _ = handle_all_events(events)
+            the_mock.assert_called()
+        finally:
+            c_void_p.in_dll(pythonapi, "PyOS_InputHook").value =  prev_value

Misc/NEWS.d/next/Core and Builtins/2024-05-31-12-06-11.gh-issue-119842.tCGVsv.rst

@@ -0,0 +1 @@
+Honor :c:func:`PyOS_InputHook` in the new REPL. Patch by Pablo Galindo

Python/pylifecycle.c

@@ -3329,3 +3329,15 @@ PyOS_setsig(int sig, PyOS_sighandler_t handler)
     return oldhandler;
 #endif
 }
+
+int _PyOS_CallInputHook(void)
+{
+    // The return value is ignored, but let's handle it anyway
+    int result = 0;
+    if (PyOS_InputHook) {
+        Py_BEGIN_ALLOW_THREADS;
+        result = PyOS_InputHook();
+        Py_END_ALLOW_THREADS;
+    }
+    return result;
+}