gh-111916: Make hashlib related modules thread-safe without the GIL (#111981)

Always use an individual lock on hash objects when in free-threaded builds.

Fixes #111916

1 files changed, 9 insertions, 10 deletions

diff --git a/Modules/sha1module.c b/Modules/sha1module.c
index 3fd5312..eda6b56 100644
--- a/Modules/sha1module.c
+++ b/Modules/sha1module.c
@@ -49,7 +49,8 @@ typedef long long SHA1_INT64;        /* 64-bit integer */
 typedef struct {
     PyObject_HEAD
     // Prevents undefined behavior via multiple threads entering the C API.
-    // The lock will be NULL before threaded access has been enabled.
+    bool use_mutex;
+    PyMutex mutex;
     PyThread_type_lock lock;
     Hacl_Streaming_SHA1_state *hash_state;
 } SHA1object;
@@ -76,7 +77,8 @@ newSHA1object(SHA1State *st)
     if (sha == NULL) {
         return NULL;
     }
-    sha->lock = NULL;
+    HASHLIB_INIT_MUTEX(sha);
+
     PyObject_GC_Track(sha);
     return sha;
 }
@@ -94,9 +96,6 @@ static void
 SHA1_dealloc(SHA1object *ptr)
 {
     Hacl_Streaming_SHA1_legacy_free(ptr->hash_state);
-    if (ptr->lock != NULL) {
-        PyThread_free_lock(ptr->lock);
-    }
     PyTypeObject *tp = Py_TYPE(ptr);
     PyObject_GC_UnTrack(ptr);
     PyObject_GC_Del(ptr);
@@ -192,14 +191,14 @@ SHA1Type_update(SHA1object *self, PyObject *obj)
 
     GET_BUFFER_VIEW_OR_ERROUT(obj, &buf);
 
-    if (self->lock == NULL && buf.len >= HASHLIB_GIL_MINSIZE) {
-        self->lock = PyThread_allocate_lock();
+    if (!self->use_mutex && buf.len >= HASHLIB_GIL_MINSIZE) {
+        self->use_mutex = true;
     }
-    if (self->lock != NULL) {
+    if (self->use_mutex) {
         Py_BEGIN_ALLOW_THREADS
-        PyThread_acquire_lock(self->lock, 1);
+        PyMutex_Lock(&self->mutex);
         update(self->hash_state, buf.buf, buf.len);
-        PyThread_release_lock(self->lock);
+        PyMutex_Unlock(&self->mutex);
         Py_END_ALLOW_THREADS
     } else {
         update(self->hash_state, buf.buf, buf.len);