[3.9] bpo-40826: Fix GIL usage in PyOS_Readline() (GH-20613)

* bpo-40826: Fix GIL usage in PyOS_Readline() (GH-20579)

Fix GIL usage in PyOS_Readline(): lock the GIL to set an exception.

Pass tstate to my_fgets() and _PyOS_WindowsConsoleReadline(). Cleanup
these functions.

(cherry picked from commit c353764fd564e401cf47a5d9efab18c72c60014e)

* bpo-40826: Add _PyOS_InterruptOccurred(tstate) function (GH-20599)

my_fgets() now calls _PyOS_InterruptOccurred(tstate) to check for
pending signals, rather calling PyOS_InterruptOccurred().

my_fgets() is called with the GIL released, whereas
PyOS_InterruptOccurred() must be called with the GIL held.

test_repl: use text=True and avoid SuppressCrashReport in
test_multiline_string_parsing().

Fix my_fgets() on Windows: fgets(fp) does crash if fileno(fp) is closed.

(cherry picked from commit fa7ab6aa0f9a4f695e5525db5a113cd21fa93787)

1 files changed, 15 insertions, 3 deletions

diff --git a/Modules/signalmodule.c b/Modules/signalmodule.c
index 8348971c353..b3f5904feb7 100644
--- a/Modules/signalmodule.c
+++ b/Modules/signalmodule.c
@@ -1779,11 +1779,13 @@ PyOS_FiniInterrupts(void)
     finisignal();
 }
 
+
+// The caller doesn't have to hold the GIL
 int
-PyOS_InterruptOccurred(void)
+_PyOS_InterruptOccurred(PyThreadState *tstate)
 {
-    PyInterpreterState *interp = _PyInterpreterState_GET();
-    if (!_Py_ThreadCanHandleSignals(interp)) {
+    assert(tstate != NULL);
+    if (!_Py_ThreadCanHandleSignals(tstate->interp)) {
         return 0;
     }
 
@@ -1795,6 +1797,16 @@ PyOS_InterruptOccurred(void)
     return 1;
 }
 
+
+// The caller must to hold the GIL
+int
+PyOS_InterruptOccurred(void)
+{
+    PyThreadState *tstate = _PyThreadState_GET();
+    return _PyOS_InterruptOccurred(tstate);
+}
+
+
 static void
 _clear_pending_signals(void)
 {