lock init on py < 3.13

Author: SwayamInSync

quaddtype/numpy_quaddtype/src/scalar.c

@@ -22,6 +22,18 @@
 // src: https://en.wikipedia.org/wiki/Quadruple-precision_floating-point_format
 #define SLEEF_QUAD_DECIMAL_DIG 36
 
+#if PY_VERSION_HEX < 0x30d00b3
+static PyThread_type_lock sleef_lock;
+#define LOCK_SLEEF PyThread_acquire_lock(sleef_lock, WAIT_LOCK)
+#define UNLOCK_SLEEF PyThread_release_lock(sleef_lock)
+#else
+static PyMutex sleef_lock = {0};
+#define LOCK_SLEEF PyMutex_Lock(&sleef_lock)
+#define UNLOCK_SLEEF PyMutex_Unlock(&sleef_lock)
+#endif
+
+
+
 
 QuadPrecisionObject *
 QuadPrecision_raw_new(QuadBackendType backend)
@@ -422,13 +434,16 @@ QuadPrecision_is_integer(QuadPrecisionObject *self, PyObject *Py_UNUSED(ignored)
     }
 }
 
-// this is thread-unsafe
 PyObject* quad_to_pylong(Sleef_quad value)
 {
     char buffer[128];
+
+    // Sleef_snprintf call is thread-unsafe
+    // LOCK_SLEEF;
     // Format as integer (%.0Qf gives integer with no decimal places)
     // Q modifier means pass Sleef_quad by value
     int written = Sleef_snprintf(buffer, sizeof(buffer), "%.0Qf", value);
+    // UNLOCK_SLEEF;
     if (written < 0 || written >= sizeof(buffer)) {
         PyErr_SetString(PyExc_RuntimeError, "Failed to convert quad to string");
         return NULL;
@@ -503,7 +518,6 @@ QuadPrecision_as_integer_ratio(QuadPrecisionObject *self, PyObject *Py_UNUSED(ig
         exponent--;
     }
 
-
     // numerator and denominators can't fit in int
     // convert items to PyLongObject from string instead
 
@@ -587,6 +601,13 @@ PyTypeObject QuadPrecision_Type = {
 int
 init_quadprecision_scalar(void)
 {
+#if PY_VERSION_HEX < 0x30d00b3
+    sleef_lock = PyThread_allocate_lock();
+    if (sleef_lock == NULL) {
+        PyErr_NoMemory();
+        return -1;
+    }
+#endif
     QuadPrecision_Type.tp_base = &PyFloatingArrType_Type;
     return PyType_Ready(&QuadPrecision_Type);
 }

quaddtype/tests/test_multithreading.py

@@ -21,11 +21,11 @@
 
 def test_as_integer_ratio_reconstruction():
     """Multi-threaded test that as_integer_ratio() can reconstruct the original value."""
-    values = ["3.14", "0.1", "1.414213562373095", "2.718281828459045",
-    "-1.23456789", "1000.001", "0.0001", "1e20", "1.23e15", "1e-30", pi]
 
     def test(barrier):
       barrier.wait() # All threads start simultaneously
+      values = ["3.14", "0.1", "1.414213562373095", "2.718281828459045",
+      "-1.23456789", "1000.001", "0.0001", "1e20", "1.23e15", "1e-30", pi]
       for val in values:
         quad_val = QuadPrecision(val)
         num, denom = quad_val.as_integer_ratio()