--- cdecimal3.c	2011-06-15 17:48:40.000000000 +0200
+++ cdecimal3_failapi.c	2011-06-15 17:48:33.000000000 +0200
@@ -142,6 +142,103 @@
 /* Top level Exception; inherits from ArithmeticError */
 static PyObject *DecimalException = NULL;
 
+/* FailAPI */
+static PyObject *FailAPIException = NULL;
+
+static unsigned long counter = 0;
+static unsigned long apicalls = 0;
+static unsigned long failpoint = 0;
+static Py_complex _cfail = {-1, -1};
+
+#define FFUNC(ret, funcall) (\
+  (++counter, ++apicalls == failpoint)                    \
+    ? (PyErr_SetString(FailAPIException, "failapi"), ret) \
+    : funcall)
+
+#define FFUNC_NOEX(ret, funcall) (\
+  (++counter, ++apicalls == failpoint) ? ret : funcall)
+
+#define IFUNC(funcall) (\
+  (++counter, ++apicalls == failpoint)                   \
+    ? (PyErr_SetString(FailAPIException, "failapi"), -1) \
+    : funcall)
+
+#define PFUNC(funcall) (\
+  (++counter, ++apicalls == failpoint)                     \
+    ? (PyErr_SetString(FailAPIException, "failapi"), NULL) \
+    : funcall)
+
+#define PFUNC_NOEX(funcall) (\
+  (++counter, ++apicalls == failpoint) ? NULL : funcall)
+
+#define SFUNC(func, result, ...) do { \
+    if (++counter, ++apicalls == failpoint)              \
+        mpd_seterror(result, MPD_Malloc_error, &status); \
+    else                                                 \
+        func(result, __VA_ARGS__);                       \
+    } while (0)
+
+static PyObject *
+get_failpoint(PyObject *self UNUSED, PyObject *dummy UNUSED)
+{
+	return Py_BuildValue("k", failpoint);
+}
+
+static PyObject *
+get_apicalls(PyObject *self UNUSED, PyObject *dummy UNUSED)
+{
+	return Py_BuildValue("k", apicalls);
+}
+
+static PyObject *
+set_failpoint(PyObject *self UNUSED, PyObject *value)
+{
+	failpoint = PyLong_AsUnsignedLong(value);
+	if (PyErr_Occurred()) {
+		return NULL; /* GCOV_NOT_REACHED */
+	}
+	Py_RETURN_NONE;
+}
+
+static PyObject *
+set_apicalls(PyObject *self UNUSED, PyObject *value)
+{
+	apicalls = PyLong_AsUnsignedLong(value);
+	if (PyErr_Occurred()) {
+		return NULL; /* GCOV_NOT_REACHED */
+	}
+	Py_RETURN_NONE;
+}
+
+void *
+mpd_malloc_fail(size_t size)
+{
+
+	if (++apicalls == failpoint) {
+		return NULL;
+	}
+	return PyMem_Malloc(size);
+}
+
+void *
+mpd_calloc_fail(size_t nmemb, size_t size)
+{
+	if (++apicalls == failpoint) {
+		return NULL;
+	}
+	return mpd_callocfunc_em(nmemb, size);
+}
+
+void *
+mpd_realloc_fail(void *ptr, size_t size)
+{
+	if (++apicalls == failpoint) {
+		return NULL;
+	}
+	return PyMem_Realloc(ptr, size);
+}
+/* End FailAPI */
+
 /* Exceptions that correspond to IEEE signals; inherit from DecimalException */
 static DecCondMap signal_map[] = {
   {"InvalidOperation", "cdecimal.InvalidOperation", MPD_IEEE_Invalid_operation, NULL},
@@ -232,7 +329,7 @@
 static int
 runtime_error_int(const char *mesg)
 {
-	PyErr_SetString(PyExc_RuntimeError, mesg);
+	PyErr_SetString(FailAPIException, mesg);
 	return -1;
 }
 #define INTERNAL_ERROR_INT(funcname) \
@@ -241,7 +338,7 @@
 static PyObject *
 runtime_error_ptr(const char *mesg)
 {
-	PyErr_SetString(PyExc_RuntimeError, mesg);
+	PyErr_SetString(FailAPIException, mesg);
 	return NULL;
 }
 #define INTERNAL_ERROR_PTR(funcname) \
@@ -288,20 +385,20 @@
 	PyObject *list;
 	DecCondMap *cm;
 
-	if ((list = PyList_New(0)) == NULL) {
+	if ((list = PFUNC(PyList_New(0))) == NULL) {
 		return NULL;
 	}
 
 	for (cm = cond_map; cm->name != NULL; cm++) {
 		if (flags&cm->mpd_cond) {
-			if (PyList_Append(list, cm->dec_cond) < 0) {
+			if (IFUNC(PyList_Append(list, cm->dec_cond)) < 0) {
 				goto error;
 			}
 		}
 	}
 	for (cm = signal_map+1; cm->name != NULL; cm++) {
 		if (flags&cm->mpd_cond) {
-			if (PyList_Append(list, cm->dec_cond) < 0) {
+			if (IFUNC(PyList_Append(list, cm->dec_cond)) < 0) {
 				goto error;
 			}
 		}
@@ -320,13 +417,13 @@
 	PyObject *list;
 	DecCondMap *cm;
 
-	if ((list = PyList_New(0)) == NULL) {
+	if ((list = PFUNC(PyList_New(0))) == NULL) {
 		return NULL;
 	}
 
 	for (cm = signal_map; cm->name != NULL; cm++) {
 		if (flags&cm->mpd_cond) {
-			if (PyList_Append(list, cm->dec_cond) < 0) {
+			if (IFUNC(PyList_Append(list, cm->dec_cond)) < 0) {
 				goto error;
 			}
 		}
@@ -380,7 +477,7 @@
 	}
 
 	for (cm = signal_map; cm->name != NULL; cm++) {
-		if ((b = PyDict_GetItemWithError(val, cm->dec_cond)) == NULL) {
+		if ((b = PFUNC(PyDict_GetItemWithError(val, cm->dec_cond))) == NULL) {
 			if (!PyErr_Occurred()) {
 				PyErr_SetString(PyExc_TypeError,
 		 		   "invalid signal dict.");
@@ -388,7 +485,7 @@
 			return UINT32_MAX;
 		}
 
-		if ((x = PyObject_IsTrue(b)) < 0) {
+		if ((x = IFUNC(PyObject_IsTrue(b))) < 0) {
 			return UINT32_MAX;
 		}
 		if (x == 1) {
@@ -404,7 +501,7 @@
 {
 	long x;
 
-	x = PyLong_AsLong(v);
+	x = IFUNC(PyLong_AsLong(v));
 	if (PyErr_Occurred()) {
 		return UINT32_MAX;
 	}
@@ -427,7 +524,7 @@
 		return MPD_SSIZE_MAX;
 	}
 
-	x = _PyLong_AsMpdSsize(v);
+	x = IFUNC(_PyLong_AsMpdSsize(v));
 	if (PyErr_Occurred()) {
 		return MPD_SSIZE_MAX;
 	}
@@ -440,6 +537,12 @@
 {
 	mpd_context_t *ctx = CTX(context);
 
+	if (status&MPD_Malloc_error) {
+		/* Translate MemoryError to FailAPIException */
+		PyErr_SetString(FailAPIException, "failapi");
+		return 1;
+	}
+
 	ctx->status |= status;
 	if (ctx->traps&status) {
 		PyObject *ex, *siglist;
@@ -468,7 +571,7 @@
 static int
 signaldict_init(PyObject *self, PyObject *args, PyObject *kwds)
 {
-	if (PyDict_Type.tp_init(self, args, kwds) < 0) {
+	if (IFUNC(PyDict_Type.tp_init(self, args, kwds)) < 0) {
 		return -1;
 	}
 
@@ -488,7 +591,7 @@
 
 	for (cm = signal_map; cm->name != NULL; cm++) {
 		b = (flags&cm->mpd_cond) ? Py_True : Py_False;
-		if (PyDict_SetItem(self, cm->dec_cond, b) < 0) {
+		if (IFUNC(PyDict_SetItem(self, cm->dec_cond, b)) < 0) {
 			return -1;
 		}
 	}
@@ -504,7 +607,7 @@
 	SdFlags(self) = 0;
 
 	for (cm = signal_map; cm->name != NULL; cm++) {
-		if (PyDict_SetItem(self, cm->dec_cond, Py_False) < 0) {
+		if (IFUNC(PyDict_SetItem(self, cm->dec_cond, Py_False)) < 0) {
 			return -1;
 		}
 	}
@@ -521,19 +624,19 @@
 		return -1;
 	}
 
-	if ((x = PyObject_IsTrue(value)) < 0) {
+	if ((x = IFUNC(PyObject_IsTrue(value))) < 0) {
 		return -1;
 	}
 	if (x == 1) {
 		SdFlags(self) |= flag;
-		if (PyDict_SetItem(self, key, Py_True) < 0) {
+		if (IFUNC(PyDict_SetItem(self, key, Py_True)) < 0) {
 			return -1;
 		}
 		return 0;
 	}
 	else {
 		SdFlags(self) &= ~flag;
-		if (PyDict_SetItem(self, key, Py_False) < 0) {
+		if (IFUNC(PyDict_SetItem(self, key, Py_False)) < 0) {
 			return -1;
 		}
 		return 0;
@@ -546,7 +649,7 @@
 	if (signaldict_update(self) < 0) {
 		return NULL;
 	}
-	return PyObject_CallMethod((PyObject *)&PyDict_Type, name, "O", self);
+	return PFUNC(PyObject_CallMethod((PyObject *)&PyDict_Type, name, "O", self));
 }
 
 static PyObject *
@@ -562,7 +665,7 @@
 			return NULL;
 		}
 	}
-	return PyDict_Type.tp_richcompare(a, b, op);
+	return PFUNC(PyDict_Type.tp_richcompare(a, b, op));
 }
 
 static int
@@ -571,7 +674,7 @@
 	if (signaldict_update(self) < 0) {
 		return -1;
 	}
-	return PyDict_Contains(self, key);
+	return IFUNC(PyDict_Contains(self, key));
 }
 
 static PyObject *
@@ -580,25 +683,25 @@
 	if (signaldict_update(self) < 0) {
 		return NULL;
 	}
-	return PyDict_Copy(self);
+	return PFUNC(PyDict_Copy(self));
 }
 
 static PyObject *
 signaldict_get(PyObject *self, PyObject *args)
 {
 	PyObject *key = NULL, *failobj = NULL;
-	if (!PyArg_ParseTuple(args, "O|O", &key, &failobj)) {
+	if (!FFUNC(0, PyArg_ParseTuple(args, "O|O", &key, &failobj))) {
 		return NULL; /* GCOV_NOT_REACHED (why?) */
 	}
 	if (signaldict_update(self) < 0) {
 		return NULL;
 	}
 	if (failobj) {
-		return PyObject_CallMethod((PyObject *)&PyDict_Type, "get",
-		                           "OOO", self, key, failobj);
+		return PFUNC(PyObject_CallMethod((PyObject *)&PyDict_Type, "get",
+		                           "OOO", self, key, failobj));
 	}
-	return PyObject_CallMethod((PyObject *)&PyDict_Type, "get",
-	                           "OO", self, key);
+	return PFUNC(PyObject_CallMethod((PyObject *)&PyDict_Type, "get",
+	                           "OO", self, key));
 }
 
 static PyObject *
@@ -608,8 +711,8 @@
 	if (signaldict_update(self) < 0) {
 		return NULL;
 	}
-	ret = PyDict_Contains(self, key);
-	return ret < 0 ? NULL : PyBool_FromLong(ret);
+	ret = IFUNC(PyDict_Contains(self, key));
+	return ret < 0 ? NULL : PFUNC(PyBool_FromLong(ret));
 }
 
 static PyObject *
@@ -618,7 +721,7 @@
 	if (signaldict_update(self) < 0) {
 		return NULL;
 	}
-	return PyDict_Items(self);
+	return PFUNC(PyDict_Items(self));
 }
 
 static PyObject *
@@ -627,7 +730,7 @@
 	if (signaldict_update(self) < 0) {
 		return NULL;
 	}
-	return PyDict_Type.tp_iter(self);
+	return PFUNC(PyDict_Type.tp_iter(self));
 }
 
 static PyObject *
@@ -636,7 +739,7 @@
 	if (signaldict_update(self) < 0) {
 		return NULL;
 	}
-	return PyDict_Keys(self);
+	return PFUNC(PyDict_Keys(self));
 }
 
 static Py_ssize_t
@@ -645,7 +748,7 @@
 	if (signaldict_update(self) < 0) {
 		return -1;
 	}
-	return PyDict_Type.tp_as_mapping->mp_length(self);
+	return IFUNC(PyDict_Type.tp_as_mapping->mp_length(self));
 }
 
 static int
@@ -663,7 +766,7 @@
 	if (signaldict_update(self) < 0) {
 		return NULL;
 	}
-	return PyDict_Type.tp_repr(self);
+	return PFUNC(PyDict_Type.tp_repr(self));
 }
 
 static PyObject *
@@ -689,7 +792,7 @@
 	if (signaldict_update(self) < 0) {
 		return NULL;
 	}
-	return PyDict_Type.tp_as_mapping->mp_subscript(self, key);
+	return PFUNC(PyDict_Type.tp_as_mapping->mp_subscript(self, key));
 }
 
 static PyObject *
@@ -698,7 +801,7 @@
 	if (signaldict_update(self) < 0) {
 		return NULL;
 	}
-	return PyDict_Values(self);
+	return PFUNC(PyDict_Values(self));
 }
 
 
@@ -785,7 +888,7 @@
 	mpd_context_t *ctx;
 
 	ctx = CTX(self);
-	return Py_BuildValue(CONV_mpd_ssize_t, mpd_getprec(ctx));
+	return PFUNC(Py_BuildValue(CONV_mpd_ssize_t, mpd_getprec(ctx)));
 }
 
 static PyObject *
@@ -794,7 +897,7 @@
 	mpd_context_t *ctx;
 
 	ctx = CTX(self);
-	return Py_BuildValue(CONV_mpd_ssize_t, mpd_getemax(ctx));
+	return PFUNC(Py_BuildValue(CONV_mpd_ssize_t, mpd_getemax(ctx)));
 }
 
 static PyObject *
@@ -803,7 +906,7 @@
 	mpd_context_t *ctx;
 
 	ctx = CTX(self);
-	return Py_BuildValue(CONV_mpd_ssize_t, mpd_getemin(ctx));
+	return PFUNC(Py_BuildValue(CONV_mpd_ssize_t, mpd_getemin(ctx)));
 }
 
 static PyObject *
@@ -812,7 +915,7 @@
 	mpd_context_t *ctx;
 
 	ctx = CTX(self);
-	return Py_BuildValue(CONV_mpd_ssize_t, mpd_etiny(ctx));
+	return PFUNC(Py_BuildValue(CONV_mpd_ssize_t, mpd_etiny(ctx)));
 }
 
 static PyObject *
@@ -821,7 +924,7 @@
 	mpd_context_t *ctx;
 
 	ctx = CTX(self);
-	return Py_BuildValue(CONV_mpd_ssize_t, mpd_etop(ctx));
+	return PFUNC(Py_BuildValue(CONV_mpd_ssize_t, mpd_etop(ctx)));
 }
 
 static PyObject *
@@ -830,13 +933,13 @@
 	mpd_context_t *ctx;
 
 	ctx = CTX(self);
-	return Py_BuildValue("i", mpd_getround(ctx));
+	return PFUNC(Py_BuildValue("i", mpd_getround(ctx)));
 }
 
 static PyObject *
 context_getcapitals(PyObject *self, void *closure UNUSED)
 {
-	return Py_BuildValue("i", CtxCaps(self));
+	return PFUNC(Py_BuildValue("i", CtxCaps(self)));
 }
 
 static PyObject *
@@ -845,7 +948,7 @@
 	mpd_context_t *ctx;
 
 	ctx = CTX(self);
-	return Py_BuildValue("i", mpd_gettraps(ctx));
+	return PFUNC(Py_BuildValue("i", mpd_gettraps(ctx)));
 }
 
 static PyObject *
@@ -854,7 +957,7 @@
 	mpd_context_t *ctx;
 
 	ctx = CTX(self);
-	return Py_BuildValue("i", mpd_getstatus(ctx));
+	return PFUNC(Py_BuildValue("i", mpd_getstatus(ctx)));
 }
 
 static PyObject *
@@ -863,7 +966,7 @@
 	mpd_context_t *ctx;
 
 	ctx = CTX(self);
-	return Py_BuildValue("i", mpd_getclamp(ctx));
+	return PFUNC(Py_BuildValue("i", mpd_getclamp(ctx)));
 }
 
 static PyObject *
@@ -872,7 +975,7 @@
 	mpd_context_t *ctx;
 
 	ctx = CTX(self);
-	return Py_BuildValue("i", mpd_getcr(ctx));
+	return PFUNC(Py_BuildValue("i", mpd_getcr(ctx)));
 }
 
 static int
@@ -1032,7 +1135,7 @@
 	}
 
 	ctx = CTX(self);
-	if (!mpd_qsettraps(ctx, flags)) {
+	if (!FFUNC_NOEX(0, mpd_qsettraps(ctx, flags))) {
 		INTERNAL_ERROR_INT("context_settraps");
 	}
 
@@ -1051,7 +1154,7 @@
 	}
 
 	ctx = CTX(self);
-	if (!mpd_qsettraps(ctx, flags)) {
+	if (!FFUNC_NOEX(0, mpd_qsettraps(ctx, flags))) {
 		INTERNAL_ERROR_INT("context_settraps_list");
 	}
 
@@ -1070,7 +1173,7 @@
 	}
 
 	ctx = CTX(self);
-	if (!mpd_qsettraps(ctx, flags)) {
+	if (!FFUNC_NOEX(0, mpd_qsettraps(ctx, flags))) {
 		INTERNAL_ERROR_INT("context_settraps_dict");
 	}
 
@@ -1089,7 +1192,7 @@
 	}
 
 	ctx = CTX(self);
-	if (!mpd_qsetstatus(ctx, flags)) {
+	if (!FFUNC_NOEX(0, mpd_qsetstatus(ctx, flags))) {
 		INTERNAL_ERROR_INT("context_setstatus");
 	}
 
@@ -1108,7 +1211,7 @@
 	}
 
 	ctx = CTX(self);
-	if (!mpd_qsetstatus(ctx, flags)) {
+	if (!FFUNC_NOEX(0, mpd_qsetstatus(ctx, flags))) {
 		INTERNAL_ERROR_INT("context_setstatus_list");
 	}
 
@@ -1127,7 +1230,7 @@
 	}
 
 	ctx = CTX(self);
-	if (!mpd_qsetstatus(ctx, flags)) {
+	if (!FFUNC_NOEX(0, mpd_qsetstatus(ctx, flags))) {
 		INTERNAL_ERROR_INT("context_setstatus_dict");
 	}
 
@@ -1256,18 +1359,18 @@
 	PyDecContextObject *self = NULL;
 	mpd_context_t *ctx;
 
-	self = PyObject_New(PyDecContextObject, &PyDecContext_Type);
+	self = PFUNC(PyObject_New(PyDecContextObject, &PyDecContext_Type));
 	if (self == NULL) {
 		return NULL;
 	}
 
-	self->traps = PyObject_CallObject((PyObject *)&PyDecSignalDict_Type, NULL);
+	self->traps = PFUNC(PyObject_CallObject((PyObject *)&PyDecSignalDict_Type, NULL));
 	if (self->traps == NULL) {
 		self->flags = NULL;
 		Py_DECREF(self);
 		return NULL;
 	}
-	self->flags = PyObject_CallObject((PyObject *)&PyDecSignalDict_Type, NULL);
+	self->flags = PFUNC(PyObject_CallObject((PyObject *)&PyDecSignalDict_Type, NULL));
 	if (self->flags == NULL) {
 		Py_DECREF(self);
 		return NULL;
@@ -1310,7 +1413,7 @@
 	int i;
 
 	if (PyLong_Check(v)) {
-		x = PyLong_AsLong(v);
+		x = IFUNC(PyLong_AsLong(v));
 		if (PyErr_Occurred()) {
 			return -1;
 		}
@@ -1349,13 +1452,13 @@
 	if (default_context_template) {
 		t = *CTX(default_context_template);
 	}
-	if (!PyArg_ParseTupleAndKeywords(
+	if (!FFUNC(0, PyArg_ParseTupleAndKeywords(
 	        args, kwds,
 	        "|" CONV_mpd_ssize_t "O" CONV_mpd_ssize_t CONV_mpd_ssize_t "ii"
 	        "OOi", kwlist,
 	        &t.prec, &rounding, &t.emin, &t.emax, &capitals, &t.clamp,
 	        &status, &traps, &t.allcr
-	     )) {
+	     ))) {
 		return -1;
 	}
 	if (rounding != NULL) {
@@ -1427,32 +1530,32 @@
 	ctx = CTX(self);
 
 	cp = s; mem = FD_CTX_LEN;
-	n = snprintf(cp, mem,
+	n = FFUNC_NOEX(-1, snprintf(cp, mem,
 	             "Context(prec=%"PRI_mpd_ssize_t", rounding=%s, "
 	             "Emin=%"PRI_mpd_ssize_t", Emax=%"PRI_mpd_ssize_t", "
 	             "capitals=%d, clamp=%d, flags=",
 	             ctx->prec, mpd_round_string[ctx->round],
 	             ctx->emin, ctx->emax,
-	             self->capitals, ctx->clamp);
+	             self->capitals, ctx->clamp));
 	if (n < 0 || n >= mem) goto error;
 	cp += n; mem -= n;
 
-	n = mpd_lsnprint_signals(cp, mem, ctx->status, dec_signal_string);
+	n = FFUNC_NOEX(-1, mpd_lsnprint_signals(cp, mem, ctx->status, dec_signal_string));
 	if (n < 0 || n >= mem) goto error;
 	cp += n; mem -= n;
 
-	n = snprintf(cp, mem, ", traps=");
+	n = FFUNC_NOEX(-1, snprintf(cp, mem, ", traps="));
 	if (n < 0 || n >= mem) goto error;
 	cp += n; mem -= n;
 
-	n = mpd_lsnprint_signals(cp, mem, ctx->traps, dec_signal_string);
+	n = FFUNC_NOEX(-1, mpd_lsnprint_signals(cp, mem, ctx->traps, dec_signal_string));
 	if (n < 0 || n >= mem) goto error;
 	cp += n; mem -= n;
 
-	n = snprintf(cp, mem, ")");
+	n = FFUNC_NOEX(-1, snprintf(cp, mem, ")"));
 	if (n < 0 || n >= mem) goto error;
 
-	return PyUnicode_FromString(s);
+	return PFUNC(PyUnicode_FromString(s));
 
 error:
 	INTERNAL_ERROR_PTR("context_repr");
@@ -1502,7 +1605,7 @@
 		goto error;
 	}
 
-	context = PyObject_CallObject((PyObject *)&PyDecContext_Type, NULL);
+	context = PFUNC(PyObject_CallObject((PyObject *)&PyDecContext_Type, NULL));
 	if (context == NULL) {
 		return NULL;
 	}
@@ -1523,7 +1626,7 @@
 {
 	PyObject *copy;
 
-	copy = PyObject_CallObject((PyObject *)&PyDecContext_Type, NULL);
+	copy = PFUNC(PyObject_CallObject((PyObject *)&PyDecContext_Type, NULL));
 	if (copy == NULL) {
 		return NULL;
 	}
@@ -1553,13 +1656,13 @@
 		return NULL;
 	}
 
-	ret = Py_BuildValue(
+	ret = PFUNC(Py_BuildValue(
 	        "O(" CONV_mpd_ssize_t "s" CONV_mpd_ssize_t CONV_mpd_ssize_t
 	        "iiOO)",
 	        Py_TYPE(self),
 	        ctx->prec, mpd_round_string[ctx->round], ctx->emin, ctx->emax,
 	        CtxCaps(self), ctx->clamp, flags, traps
-	);
+	));
 
 	Py_DECREF(flags);
 	Py_DECREF(traps);
@@ -1698,14 +1801,14 @@
 	PyObject *dict = NULL;
 	PyObject *tl_context = NULL;
 
-	dict = PyThreadState_GetDict();
+	dict = PFUNC_NOEX(PyThreadState_GetDict());
 	if (dict == NULL) {
-		PyErr_SetString(PyExc_RuntimeError,
+		PyErr_SetString(FailAPIException,
 		    "cannot get thread state.");
 		return NULL;
 	}
 
-	tl_context = PyDict_GetItemWithError(dict, tls_context_key);
+	tl_context = PFUNC(PyDict_GetItemWithError(dict, tls_context_key));
 	if (tl_context != NULL) {
 		/* We already have a thread local context and
 		 * return a borrowed reference. */
@@ -1721,7 +1824,7 @@
 	if (tl_context == NULL) {
 		return NULL;
 	}
-	if (PyDict_SetItem(dict, tls_context_key, tl_context) < 0) {
+	if (IFUNC(PyDict_SetItem(dict, tls_context_key, tl_context)) < 0) {
 		Py_DECREF(tl_context);
 		return NULL;
 	}
@@ -1768,9 +1871,9 @@
 
 	CONTEXT_CHECK(v);
 
-	dict = PyThreadState_GetDict();
+	dict = PFUNC_NOEX(PyThreadState_GetDict());
 	if (dict == NULL) {
-		PyErr_SetString(PyExc_RuntimeError,
+		PyErr_SetString(FailAPIException,
 		    "cannot get thread state.");
 		return NULL;
 	}
@@ -1788,7 +1891,7 @@
 		Py_INCREF(v);
 	}
 
-	if (PyDict_SetItem(dict, tls_context_key, v) < 0) {
+	if (IFUNC(PyDict_SetItem(dict, tls_context_key, v)) < 0) {
 		Py_DECREF(v);
 		return NULL;
 	}
@@ -1810,13 +1913,13 @@
 
 	CURRENT_CONTEXT(global);
 	local = global;
-	if (!PyArg_ParseTuple(args, "|O", &local)) {
+	if (!FFUNC(0, PyArg_ParseTuple(args, "|O", &local))) {
 		return NULL;
 	}
 	CONTEXT_CHECK_VA(local);
 
-	self = PyObject_New(PyDecContextManagerObject,
-	                    &PyDecContextManager_Type);
+	self = PFUNC(PyObject_New(PyDecContextManagerObject,
+	                    &PyDecContextManager_Type));
 	if (self == NULL) {
 		return NULL;
 	}
@@ -1864,6 +1967,19 @@
 
 	ret = PyDec_SetCurrentContext(NULL, self->global);
 	if (ret == NULL) {
+		/* This particular failpoint leaves the global state
+		   undefined (global context is not restored, but the
+		   exception is swallowed by the test suite). So we
+		   make sure that the proper exception has occcurred,
+		   restore the context and reraise the esception. */
+		assert(PyErr_Occurred() == FailAPIException);
+		PyErr_Clear();
+
+		ret = PyDec_SetCurrentContext(NULL, self->global);
+		PyErr_SetString(FailAPIException, "failapi");
+
+		assert(ret != NULL);
+		Py_DECREF(ret);
 		return NULL;
 	}
 	Py_DECREF(ret);
@@ -1921,10 +2037,10 @@
 	PyObject *dec;
 
 	if (type == &PyDec_Type) {
-		dec = (PyObject *)PyObject_New(PyDecObject, &PyDec_Type);
+		dec = (PyObject *)PFUNC(PyObject_New(PyDecObject, &PyDec_Type));
 	}
 	else {
-		dec = type->tp_alloc(type, 0);
+		dec = PFUNC(type->tp_alloc(type, 0));
 	}
 	if (dec == NULL) {
 		return NULL;
@@ -1933,7 +2049,7 @@
 	MPD(dec) = mpd_qnew();
 	if (MPD(dec) == NULL) {
 		Py_DECREF(dec);
-		PyErr_NoMemory();
+		PyErr_SetString(FailAPIException, "failapi");
 		return NULL;
 	}
 
@@ -2015,14 +2131,14 @@
 {
 	char *s;
 
-	s = PyMem_Malloc(PyUnicode_GET_SIZE(u)+1);
+	s = PFUNC_NOEX(PyMem_Malloc(PyUnicode_GET_SIZE(u)+1));
 	if (s == NULL) {
-		PyErr_NoMemory();
+		PyErr_SetString(FailAPIException, "failapi");
 		return NULL;
 	}
-	if (PyUnicode_EncodeDecimal(PyUnicode_AS_UNICODE(u),
+	if (IFUNC(PyUnicode_EncodeDecimal(PyUnicode_AS_UNICODE(u),
 	                            PyUnicode_GET_SIZE(u),
-	                            s, NULL)) {
+	                            s, NULL))) {
 		PyMem_Free(s);
 		return NULL;
 	}
@@ -2050,8 +2166,8 @@
 
 	if (s != x || t != y) {
 		n = t-s;
-		if ((y = PyMem_Malloc(n+1)) == NULL) {
-			PyErr_NoMemory();
+		if ((y = PFUNC_NOEX(PyMem_Malloc(n+1))) == NULL) {
+			PyErr_SetString(FailAPIException, "failapi");
 			return NULL;
 		}
 		strncpy(y, s, n);
@@ -2143,7 +2259,7 @@
 		return NULL;
 	}
 
-	mpd_qset_ssize(MPD(dec), v, CTX(context), &status);
+	SFUNC(mpd_qset_ssize, MPD(dec), v, CTX(context), &status);
 	if (dec_addstatus(context, status)) {
 		Py_DECREF(dec);
 		return NULL;
@@ -2166,7 +2282,7 @@
 
 	mpd_maxcontext(&maxctx);
 
-	mpd_qset_ssize(MPD(dec), v, &maxctx, &status);
+	SFUNC(mpd_qset_ssize, MPD(dec), v, &maxctx, &status);
 	if (dec_addstatus(context, status)) {
 		Py_DECREF(dec);
 		return NULL;
@@ -2303,7 +2419,7 @@
 		return NULL;
 	}
 
-	x = PyFloat_AsDouble(v);
+	x = IFUNC(PyFloat_AsDouble(v));
 	if (x == -1.0 && PyErr_Occurred()) {
 		return NULL;
 	}
@@ -2326,13 +2442,13 @@
 	}
 
 	/* absolute value of the float */
-	tmp = PyObject_CallMethod(v, "__abs__", NULL);
+	tmp = PFUNC(PyObject_CallMethod(v, "__abs__", NULL));
 	if (tmp == NULL) {
 		return NULL;
 	}
 
 	/* float as integer ratio: numerator/denominator */
-	n_d = PyObject_CallMethod(tmp, "as_integer_ratio", NULL);
+	n_d = PFUNC(PyObject_CallMethod(tmp, "as_integer_ratio", NULL));
 	Py_DECREF(tmp);
 	if (n_d == NULL) {
 		return NULL;
@@ -2340,7 +2456,7 @@
 	n = PyTuple_GET_ITEM(n_d, 0);
 	d = PyTuple_GET_ITEM(n_d, 1);
 
-	tmp = PyObject_CallMethod(d, "bit_length", NULL);
+	tmp = PFUNC(PyObject_CallMethod(d, "bit_length", NULL));
 	if (tmp == NULL) {
 		Py_DECREF(n_d);
 		return NULL;
@@ -2362,14 +2478,14 @@
 	d1 = mpd_qnew();
 	if (d1 == NULL) {
 		Py_DECREF(dec);
-		PyErr_NoMemory();
+		PyErr_SetString(FailAPIException, "failapi");
 		return NULL;
 	}
 	d2 = mpd_qnew();
 	if (d2 == NULL) {
 		mpd_del(d1);
 		Py_DECREF(dec);
-		PyErr_NoMemory();
+		PyErr_SetString(FailAPIException, "failapi");
 		return NULL;
 	}
 
@@ -2448,7 +2564,7 @@
 		    "sign must be an integer with the value 0 or 1.");
 		goto error;
 	}
-	sign = PyLong_AsLong(tmp);
+	sign = IFUNC(PyLong_AsLong(tmp));
 	if (PyErr_Occurred()) {
 		goto error;
 	}
@@ -2504,15 +2620,15 @@
 	tsize = PyTuple_Size(digits);
 	/* [sign][coeffdigits+1][E][-][expdigits+1]['\0'] */
 	mem = 1 + tsize + 3 + MPD_EXPDIGITS + 2;
-	cp = decstring = PyMem_Malloc(mem);
+	cp = decstring = PFUNC_NOEX(PyMem_Malloc(mem));
 	if (decstring == NULL) {
-		PyErr_NoMemory();
+		PyErr_SetString(FailAPIException, "failapi");
 		goto error;
 	}
 
-	n = snprintf(cp, mem, "%s", sign_special);
+	n = FFUNC(-1, snprintf(cp, mem, "%s", sign_special));
 	if (n < 0 || n >= mem) {
-		PyErr_SetString(PyExc_RuntimeError,
+		PyErr_SetString(FailAPIException,
 		    "internal error in dec_sequence_as_str.");
 		goto error;
 	}
@@ -2529,7 +2645,7 @@
 			    "coefficient must be a tuple of digits.");
 			goto error;
 		}
-		l = PyLong_AsLong(tmp);
+		l = IFUNC(PyLong_AsLong(tmp));
 		if (PyErr_Occurred()) {
 			goto error;
 		}
@@ -2545,9 +2661,9 @@
 	if (sign_special[1] == '\0') {
 		/* not a special number */
 		*cp++ = 'E';
-		n = snprintf(cp, MPD_EXPDIGITS+1, "%" PRI_mpd_ssize_t, exp);
+		n = FFUNC(-1, snprintf(cp, MPD_EXPDIGITS+1, "%" PRI_mpd_ssize_t, exp));
 		if (n < 0 || n >= MPD_EXPDIGITS+1) {
-			PyErr_SetString(PyExc_RuntimeError,
+			PyErr_SetString(FailAPIException,
 			    "internal error in dec_sequence_as_str.");
 			goto error;
 		}
@@ -2688,13 +2804,13 @@
 		return NULL;
 	}
 
-	mpd_qcopy(MPD(result), MPD(v), &status);
+	SFUNC(mpd_qcopy, MPD(result), MPD(v), &status);
 	if (dec_addstatus(context, status)) {
 		Py_DECREF(result);
 		return NULL;
 	}
 
-	mpd_qfinalize(MPD(result), CTX(context), &status);
+	SFUNC(mpd_qfinalize, MPD(result), CTX(context), &status);
 	if (dec_addstatus(context, status)) {
 		Py_DECREF(result);
 		return NULL;
@@ -2799,7 +2915,7 @@
 	PyObject *context;
 
 	CURRENT_CONTEXT(context);
-	if (!PyArg_ParseTuple(args, "|OO", &v, &context)) {
+	if (!FFUNC(0, PyArg_ParseTuple(args, "|OO", &v, &context))) {
 		return NULL;
 	}
 	CONTEXT_CHECK_VA(context);
@@ -2812,7 +2928,7 @@
 {
 	PyObject *v = NULL;
 
-	if (!PyArg_ParseTuple(args, "|O", &v)) {
+	if (!FFUNC(0, PyArg_ParseTuple(args, "|O", &v))) {
 		return NULL;
 	}
 
@@ -2936,7 +3052,7 @@
 	mpd_t *vv;
 
 	/* v is not special, r is a rational */
-	tmp = PyObject_GetAttrString(r, "denominator");
+	tmp = PFUNC(PyObject_GetAttrString(r, "denominator"));
 	if (tmp == NULL) {
 		return NULL;
 	}
@@ -2949,7 +3065,7 @@
 	vv = mpd_qncopy(MPD(v));
 	if (vv == NULL) {
 		Py_DECREF(denom);
-		PyErr_NoMemory();
+		PyErr_SetString(FailAPIException, "failapi");
 		return NULL;
 	}
 	result = dec_alloc();
@@ -2989,7 +3105,7 @@
 {
 	PyObject *tmp, *num;
 
-	tmp = PyObject_GetAttrString(r, "numerator");
+	tmp = PFUNC(PyObject_GetAttrString(r, "numerator"));
 	if (tmp == NULL) {
 		return NULL;
 	}
@@ -3037,12 +3153,12 @@
 	}
 #if PY_VERSION_HEX >= 0x03020000
 	else if (PyComplex_Check(w) && (op == Py_EQ || op == Py_NE)) {
-		Py_complex c = PyComplex_AsCComplex(w);
+		Py_complex c = FFUNC(_cfail, PyComplex_AsCComplex(w));
 		if (PyErr_Occurred()) {
 			*wcmp = NULL;
 		}
 		else if (c.imag == 0.0) {
-			PyObject *tmp = PyFloat_FromDouble(c.real);
+			PyObject *tmp = PFUNC(PyFloat_FromDouble(c.real));
 			if (tmp == NULL) {
 				*wcmp = NULL;
 			}
@@ -3102,11 +3218,11 @@
 	CURRENT_CONTEXT(c);
 	res = mpd_to_sci(MPD(dec), CtxCaps(c));
 	if (res == NULL) {
-		PyErr_NoMemory();
+		PyErr_SetString(FailAPIException, "failapi");
 		return NULL;
 	}
 
-	s = PyUnicode_FromString(res);
+	s = PFUNC(PyUnicode_FromString(res));
 	mpd_free(res);
 
 	return s;
@@ -3127,16 +3243,18 @@
 	CURRENT_CONTEXT(c);
 	cp = mpd_to_sci(MPD(dec), CtxCaps(c));
 	if (cp == NULL) {
-		PyErr_NoMemory();
+		PyErr_SetString(FailAPIException, "failapi");
 		return NULL;
 	}
 	declen = strlen(cp);
 
 	err = 0;
+	mpd_reallocfunc = mpd_realloc_fail;
 	cp = mpd_realloc(cp, (mpd_size_t)(declen+dtaglen+3), sizeof *cp, &err);
+	mpd_reallocfunc = PyMem_Realloc;
 	if (err) {
 		mpd_free(cp);
-		PyErr_NoMemory();
+		PyErr_SetString(FailAPIException, "failapi");
 		return NULL;
 	}
 
@@ -3146,7 +3264,7 @@
 	cp[declen+dtaglen+1] = ')';
 	cp[declen+dtaglen+2] = '\0';
 
-	s = PyUnicode_FromString(cp);
+	s = PFUNC(PyUnicode_FromString(cp));
 
 	mpd_free(cp);
 	return s;
@@ -3173,12 +3291,12 @@
 
 
 	CURRENT_CONTEXT(context);
-	if (!PyArg_ParseTuple(args, "O|O", &fmtarg, &override)) {
+	if (!FFUNC(0, PyArg_ParseTuple(args, "O|O", &fmtarg, &override))) {
 		return NULL;
 	}
 
 	if (PyUnicode_Check(fmtarg)) {
-		if ((fmt = PyUnicode_AsUTF8String(fmtarg)) == NULL) {
+		if ((fmt = PFUNC(PyUnicode_AsUTF8String(fmtarg))) == NULL) {
 			return NULL;
 		}
 	}
@@ -3201,19 +3319,19 @@
 			goto finish;
 		}
 		if ((dot = PyDict_GetItemString(override, "decimal_point"))) {
-			if ((dot = PyUnicode_AsUTF8String(dot)) == NULL) {
+			if ((dot = PFUNC(PyUnicode_AsUTF8String(dot))) == NULL) {
 				goto finish;
 			}
 			spec.dot = PyBytes_AS_STRING(dot);
 		}
 		if ((sep = PyDict_GetItemString(override, "thousands_sep"))) {
-			if ((sep = PyUnicode_AsUTF8String(sep)) == NULL) {
+			if ((sep = PFUNC(PyUnicode_AsUTF8String(sep))) == NULL) {
 				goto finish;
 			}
 			spec.sep = PyBytes_AS_STRING(sep);
 		}
 		if ((grouping = PyDict_GetItemString(override, "grouping"))) {
-			if ((grouping = PyUnicode_AsUTF8String(grouping)) == NULL) {
+			if ((grouping = PFUNC(PyUnicode_AsUTF8String(grouping))) == NULL) {
 				goto finish;
 			}
 			spec.grouping = PyBytes_AS_STRING(grouping);
@@ -3222,17 +3340,17 @@
 	else {
 		n = strlen(spec.dot);
 		if (n > 1 || (n == 1 && !isascii((uchar)spec.dot[0]))) {
-			n = mbstowcs(buf, spec.dot, 2);
+			n = FFUNC_NOEX((size_t)-1, mbstowcs(buf, spec.dot, 2));
 			if (n != 1) {
-				PyErr_SetString(PyExc_ValueError,
+				PyErr_SetString(FailAPIException,
 				    "invalid decimal point or unsupported "
 				    "combination of LC_CTYPE and LC_NUMERIC.");
 				goto finish;
 			}
-			if ((tmp = PyUnicode_FromWideChar(buf, n)) == NULL) {
+			if ((tmp = PFUNC(PyUnicode_FromWideChar(buf, n))) == NULL) {
 				goto finish;
 			}
-			if ((dot = PyUnicode_AsUTF8String(tmp)) == NULL) {
+			if ((dot = PFUNC(PyUnicode_AsUTF8String(tmp))) == NULL) {
 				Py_DECREF(tmp);
 				goto finish;
 			}
@@ -3241,17 +3359,17 @@
 		}
 		n = strlen(spec.sep);
 		if (n > 1 || (n == 1 && !isascii((uchar)spec.sep[0]))) {
-			n = mbstowcs(buf, spec.sep, 2);
+			n = FFUNC_NOEX((size_t)-1, mbstowcs(buf, spec.sep, 2));
 			if (n != 1) {
-				PyErr_SetString(PyExc_ValueError,
+				PyErr_SetString(FailAPIException,
 				    "invalid thousands separator or unsupported "
 				    "combination of LC_CTYPE and LC_NUMERIC.");
 				goto finish;
 			}
-			if ((tmp = PyUnicode_FromWideChar(buf, n)) == NULL) {
+			if ((tmp = PFUNC(PyUnicode_FromWideChar(buf, n))) == NULL) {
 				goto finish;
 			}
-			if ((sep = PyUnicode_AsUTF8String(tmp)) == NULL) {
+			if ((sep = PFUNC(PyUnicode_AsUTF8String(tmp))) == NULL) {
 				Py_DECREF(tmp);
 				goto finish;
 			}
@@ -3266,7 +3384,7 @@
 		dec_addstatus(context, status);
 		goto finish;
 	}
-	result = PyUnicode_DecodeUTF8(decstring, strlen(decstring), NULL);
+	result = PFUNC(PyUnicode_DecodeUTF8(decstring, strlen(decstring), NULL));
 
 
 finish:
@@ -3303,24 +3421,24 @@
 	}
 
 	if ((x = mpd_qnew()) == NULL) {
-		PyErr_NoMemory();
+		PyErr_SetString(FailAPIException, "failapi");
 		return NULL;
 	}
 	workctx = *CTX(context);
 	workctx.round = round;
-	mpd_qround_to_int(x, MPD(dec), &workctx, &status);
+	SFUNC(mpd_qround_to_int, x, MPD(dec), &workctx, &status);
 	if (dec_addstatus(context, status)) {
 		mpd_del(x);
 		return NULL;
 	}
 
-	maxsize = mpd_sizeinbase(x, PyLong_BASE);
+	maxsize = FFUNC_NOEX((size_t)PY_SSIZE_T_MAX+1, mpd_sizeinbase(x, PyLong_BASE));
 	if (maxsize > PY_SSIZE_T_MAX) {
 		mpd_del(x);
-		PyErr_NoMemory();
+		PyErr_SetString(FailAPIException, "failapi");
 		return NULL;
 	}
-	if ((pylong = _PyLong_New(maxsize)) == NULL) {
+	if ((pylong = PFUNC(_PyLong_New(maxsize))) == NULL) {
 		mpd_del(x);
 		return NULL;
 	}
@@ -3364,8 +3482,8 @@
 	int round = -1;
 
 	CURRENT_CONTEXT(context);
-	if (!PyArg_ParseTupleAndKeywords(args, kwds, "|iO", kwlist,
-	                                 &round, &context)) {
+	if (!FFUNC(0, PyArg_ParseTupleAndKeywords(args, kwds, "|iO", kwlist,
+	                                 &round, &context))) {
 		return NULL;
 	}
 	CONTEXT_CHECK_VA(context);
@@ -3381,7 +3499,7 @@
 		return NULL;
 	}
 
-	mpd_qround_to_int(MPD(result), MPD(dec), &workctx, &status);
+	SFUNC(mpd_qround_to_int, MPD(result), MPD(dec), &workctx, &status);
 	if (dec_addstatus(context, status)) {
 		Py_DECREF(result);
 		return NULL;
@@ -3401,8 +3519,8 @@
 	int round = -1;
 
 	CURRENT_CONTEXT(context);
-	if (!PyArg_ParseTupleAndKeywords(args, kwds, "|iO", kwlist,
-	                                 &round, &context)) {
+	if (!FFUNC(0, PyArg_ParseTupleAndKeywords(args, kwds, "|iO", kwlist,
+	                                 &round, &context))) {
 		return NULL;
 	}
 	CONTEXT_CHECK_VA(context);
@@ -3452,7 +3570,7 @@
 
 
 	CURRENT_CONTEXT(context);
-	if (!PyArg_ParseTuple(args, "|O", &x)) {
+	if (!FFUNC(0, PyArg_ParseTuple(args, "|O", &x))) {
 		return NULL;
 	}
 
@@ -3505,28 +3623,28 @@
 
 
 	if ((x = mpd_qncopy(MPD(dec))) == NULL) {
-		PyErr_NoMemory();
+		PyErr_SetString(FailAPIException, "failapi");
 		goto out;
 	}
 
-	sign = Py_BuildValue("i", mpd_sign(MPD(dec)));
+	sign = PFUNC(Py_BuildValue("i", mpd_sign(MPD(dec))));
 	if (sign == NULL) goto out;
 
 	if (mpd_isinfinite(x)) {
-		if ((expt = Py_BuildValue("s", "F")) == NULL) {
+		if ((expt = PFUNC(Py_BuildValue("s", "F"))) == NULL) {
 			goto out;
 		}
 		/* decimal.py has non-compliant infinity payloads. */
-		if ((coeff = Py_BuildValue("(i)", 0)) == NULL) {
+		if ((coeff = PFUNC(Py_BuildValue("(i)", 0))) == NULL) {
 			goto out;
 		}
 	}
 	else {
 		if (mpd_isnan(x)) {
-			expt = Py_BuildValue("s", mpd_isqnan(x)?"n":"N");
+			expt = PFUNC(Py_BuildValue("s", mpd_isqnan(x)?"n":"N"));
 		}
 		else {
-			expt = Py_BuildValue(CONV_mpd_ssize_t, MPD(dec)->exp);
+			expt = PFUNC(Py_BuildValue(CONV_mpd_ssize_t, MPD(dec)->exp));
 		}
 		if (expt == NULL) goto out;
 
@@ -3539,30 +3657,30 @@
 			mpd_clear_flags(x);
 			intstring = mpd_to_sci(x, 1);
 			if (intstring == NULL) {
-				PyErr_NoMemory();
+				PyErr_SetString(FailAPIException, "failapi");
 				goto out;
 			}
 
 			intlen = strlen(intstring);
-			if ((coeff = PyTuple_New(intlen)) == NULL) {
+			if ((coeff = PFUNC(PyTuple_New(intlen))) == NULL) {
 				goto out;
 			}
 
 			for (i = 0; i < intlen; i++) {
-				tmp = Py_BuildValue("i", intstring[i]-'0');
+				tmp = PFUNC(Py_BuildValue("i", intstring[i]-'0'));
 				if (tmp == NULL) goto out;
 				PyTuple_SET_ITEM(coeff, i, tmp);
 			}
 		}
 		else {
-			if ((coeff = PyTuple_New(0)) == NULL) {
+			if ((coeff = PFUNC(PyTuple_New(0))) == NULL) {
 				goto out;
 			}
 		}
 	}
 
-	result = PyObject_CallFunctionObjArgs(DecimalTuple,
-	                                      sign, coeff, expt, NULL);
+	result = PFUNC(PyObject_CallFunctionObjArgs(DecimalTuple,
+	                                      sign, coeff, expt, NULL));
 
 out:
 	if (x) mpd_del(x);
@@ -3647,7 +3765,7 @@
         PyObject *context;                             \
                                                        \
         CURRENT_CONTEXT(context);                      \
-        if (!PyArg_ParseTuple(args, "|O", &context)) { \
+        if (!FFUNC(0, PyArg_ParseTuple(args, "|O", &context))) { \
                 return NULL;                           \
         }                                              \
         CONTEXT_CHECK_VA(context);                     \
@@ -3666,7 +3784,7 @@
         uint32_t status = 0;                                    \
                                                                 \
         CURRENT_CONTEXT(context);                               \
-        if (!PyArg_ParseTuple(args, "|O", &context)) {          \
+        if (!FFUNC(0, PyArg_ParseTuple(args, "|O", &context))) {          \
                 return NULL;                                    \
         }                                                       \
         CONTEXT_CHECK_VA(context);                              \
@@ -3695,7 +3813,7 @@
         uint32_t status = 0;                                         \
                                                                      \
         CURRENT_CONTEXT(context);                                    \
-        if (!PyArg_ParseTuple(args, "O|O", &w, &context)) {          \
+        if (!FFUNC(0, PyArg_ParseTuple(args, "O|O", &w, &context))) {          \
                 return NULL;                                         \
         }                                                            \
         CONTEXT_CHECK_VA(context);                                   \
@@ -3729,7 +3847,7 @@
         PyObject *result;                                   \
                                                             \
         CURRENT_CONTEXT(context);                           \
-        if (!PyArg_ParseTuple(args, "O|O", &w, &context)) { \
+        if (!FFUNC(0, PyArg_ParseTuple(args, "O|O", &w, &context))) { \
                 return NULL;                                \
         }                                                   \
         CONTEXT_CHECK_VA(context);                          \
@@ -3759,7 +3877,7 @@
         uint32_t status = 0;                                                 \
                                                                              \
         CURRENT_CONTEXT(context);                                            \
-        if (!PyArg_ParseTuple(args, "OO|O", &w, &x, &context)) {             \
+        if (!FFUNC(0, PyArg_ParseTuple(args, "OO|O", &w, &x, &context))) {             \
                 return NULL;                                                 \
         }                                                                    \
         CONTEXT_CHECK_VA(context);                                           \
@@ -3848,7 +3966,7 @@
 		return NULL;
 	}
 
-	ret = Py_BuildValue("(OO)", q, r);
+	ret = PFUNC(Py_BuildValue("(OO)", q, r));
 	Py_DECREF(r);
 	Py_DECREF(q);
 	return ret;
@@ -3963,7 +4081,7 @@
 		retval = mpd_adjexp(MPD(self));
 	}
 
-	return _PyLong_FromMpdSsize(retval);
+	return PFUNC(_PyLong_FromMpdSsize(retval));
 }
 
 /* Apply either the current context or the context provided as an optional
@@ -3974,7 +4092,7 @@
 	PyObject *context;
 
 	CURRENT_CONTEXT(context);
-	if (!PyArg_ParseTuple(args, "|O", &context)) {
+	if (!FFUNC(0, PyArg_ParseTuple(args, "|O", &context))) {
 		return NULL;
 	}
 	CONTEXT_CHECK_VA(context);
@@ -3994,7 +4112,7 @@
 		return NULL;
 	}
 
-	mpd_qcopy_abs(MPD(result), MPD(self), &status);
+	SFUNC(mpd_qcopy_abs, MPD(result), MPD(self), &status);
 	if (dec_addstatus(context, status)) {
 		Py_DECREF(result);
 		return NULL;
@@ -4015,7 +4133,7 @@
 		return NULL;
 	}
 
-	mpd_qcopy_negate(MPD(result), MPD(self), &status);
+	SFUNC(mpd_qcopy_negate, MPD(result), MPD(self), &status);
 	if (dec_addstatus(context, status)) {
 		Py_DECREF(result);
 		return NULL;
@@ -4047,7 +4165,7 @@
 		return NULL;
 	}
 
-	mpd_qcopy_sign(MPD(result), MPD(a), MPD(b), &status);
+	SFUNC(mpd_qcopy_sign, MPD(result), MPD(a), MPD(b), &status);
 	Py_DECREF(a);
 	Py_DECREF(b);
 	if (dec_addstatus(context, status)) {
@@ -4073,13 +4191,13 @@
 	const char *cp;
 
 	CURRENT_CONTEXT(context);
-	if (!PyArg_ParseTuple(args, "|O", &context)) {
+	if (!FFUNC(0, PyArg_ParseTuple(args, "|O", &context))) {
 		return NULL;
 	}
 	CONTEXT_CHECK_VA(context);
 
 	cp = mpd_class(MPD(self), CTX(context));
-	return Py_BuildValue("s", cp);
+	return PFUNC(Py_BuildValue("s", cp));
 }
 
 static PyObject *
@@ -4106,7 +4224,7 @@
 	PyObject *ret;
 
 	CURRENT_CONTEXT(context);
-	if (!PyArg_ParseTuple(args, "O|O", &w, &context)) {
+	if (!FFUNC(0, PyArg_ParseTuple(args, "O|O", &w, &context))) {
 		return NULL;
 	}
 	CONTEXT_CHECK_VA(context);
@@ -4133,7 +4251,7 @@
 		return NULL;
 	}
 
-	ret = Py_BuildValue("(OO)", q, r);
+	ret = PFUNC(Py_BuildValue("(OO)", q, r));
 	Py_DECREF(r);
 	Py_DECREF(q);
 	return ret;
@@ -4151,8 +4269,8 @@
 	int round = -1;
 
 	CURRENT_CONTEXT(context);
-	if (!PyArg_ParseTupleAndKeywords(args, kwds, "O|iO", kwlist,
-	                                 &w, &round, &context)) {
+	if (!FFUNC(0, PyArg_ParseTupleAndKeywords(args, kwds, "O|iO", kwlist,
+	                                 &w, &round, &context))) {
 		return NULL;
 	}
 	CONTEXT_CHECK_VA(context);
@@ -4204,7 +4322,7 @@
 	PyObject *a, *b;
 
 	CURRENT_CONTEXT(context);
-	if (!PyArg_ParseTuple(args, "O|O", &w, &context)) {
+	if (!FFUNC(0, PyArg_ParseTuple(args, "O|O", &w, &context))) {
 		return NULL;
 	}
 	CONTEXT_CHECK_VA(context);
@@ -4221,7 +4339,7 @@
 static PyObject *
 dec_mpd_sign(PyObject *self, PyObject *dummy UNUSED)
 {
-	return Py_BuildValue("i", mpd_arith_sign(MPD(self)));
+	return PFUNC(Py_BuildValue("i", mpd_arith_sign(MPD(self))));
 }
 
 static PyObject *
@@ -4232,18 +4350,18 @@
 	char *s;
 
 	CURRENT_CONTEXT(context);
-	if (!PyArg_ParseTuple(args, "|O", &context)) {
+	if (!FFUNC(0, PyArg_ParseTuple(args, "|O", &context))) {
 		return NULL;
 	}
 	CONTEXT_CHECK_VA(context);
 
 	s = mpd_to_sci(MPD(self), CtxCaps(context));
 	if (s == NULL) {
-		PyErr_NoMemory();
+		PyErr_SetString(FailAPIException, "failapi");
 		return NULL;
 	}
 
-	result = PyUnicode_FromString(s);
+	result = PFUNC(PyUnicode_FromString(s));
 	mpd_free(s);
 
 	return result;
@@ -4257,18 +4375,18 @@
 	char *s;
 
 	CURRENT_CONTEXT(context);
-	if (!PyArg_ParseTuple(args, "|O", &context)) {
+	if (!FFUNC(0, PyArg_ParseTuple(args, "|O", &context))) {
 		return NULL;
 	}
 	CONTEXT_CHECK_VA(context);
 
 	s = mpd_to_eng(MPD(self), CtxCaps(context));
 	if (s == NULL) {
-		PyErr_NoMemory();
+		PyErr_SetString(FailAPIException, "failapi");
 		return NULL;
 	}
 
-	result = PyUnicode_FromString(s);
+	result = PFUNC(PyUnicode_FromString(s));
 	mpd_free(s);
 
 	return result;
@@ -4359,11 +4477,11 @@
 	long result;
 
 	if ((a = dec_alloc()) == NULL) {
-		PyErr_NoMemory();
+		PyErr_SetString(FailAPIException, "failapi");
 		return -1;
 	}
-	if (!mpd_qcopy(MPD(a), MPD(v), &status)) {
-		PyErr_NoMemory();
+	if (!FFUNC_NOEX(0, mpd_qcopy(MPD(a), MPD(v), &status))) {
+		PyErr_SetString(FailAPIException, "failapi");
 		result = -1;
 		goto finish;
 	}
@@ -4393,8 +4511,8 @@
 		}
 		mpd_maxcontext(&maxcontext);
 
-		if ((tmp = mpd_qnew()) == NULL) {
-			PyErr_NoMemory();
+		if ((tmp = PFUNC_NOEX(mpd_qnew())) == NULL) {
+			PyErr_SetString(FailAPIException, "failapi");
 			result = -1;
 			goto finish;
 		}
@@ -4404,7 +4522,7 @@
 		mpd_qset_ssize(tmp, MPD(a)->exp, &maxcontext, &status);
 		mpd_qpowmod(tmp, &ten, tmp, &two64m1, &maxcontext, &status);
 		MPD(a)->exp = 0;
-		mpd_qmul(MPD(a), MPD(a), tmp, &maxcontext, &status);
+		SFUNC(mpd_qmul, MPD(a), MPD(a), tmp, &maxcontext, &status);
 
 		if (status&MPD_Errors) {
 			if (dec_addstatus(context, status)) {
@@ -4436,12 +4554,12 @@
 
 		cp = mpd_to_sci(MPD(a), 1);
 		if (cp == NULL) {
-			PyErr_NoMemory();
+			PyErr_SetString(FailAPIException, "failapi");
 			result = -1;
 			goto finish;
 		}
 
-		obj = Py_BuildValue("(i"CONV_mpd_ssize_t"s)", sign, exp, cp);
+		obj = PFUNC(Py_BuildValue("(i"CONV_mpd_ssize_t"s)", sign, exp, cp));
 		if (obj == NULL) {
 			result = -1;
 			goto finish;
@@ -4539,7 +4657,7 @@
 	}
 
 	/* hash = (int(v) * exp_hash) % p */
-	if (!mpd_qcopy(tmp, MPD(v), &status)) {
+	if (!FFUNC_NOEX(0, mpd_qcopy(tmp, MPD(v), &status))) {
 		goto malloc_error;
 	}
 	tmp->exp = 0;
@@ -4566,7 +4684,7 @@
 	return result;
 
 malloc_error:
-	PyErr_NoMemory();
+	PyErr_SetString(FailAPIException, "failapi");
 	result = -1;
 	goto finish;
 }
@@ -4581,7 +4699,7 @@
 		return NULL;
 	}
 
-	result = Py_BuildValue("O(O)", Py_TYPE(self), str);
+	result = PFUNC(Py_BuildValue("O(O)", Py_TYPE(self), str));
 	Py_DECREF(str);
 
 	return result;
@@ -4620,17 +4738,17 @@
 	PyObject *f;
 	double x;
 
-	if ((f = PyDec_AsFloat(self)) == NULL) {
+	if ((f = PFUNC(PyDec_AsFloat(self))) == NULL) {
 		return NULL;
 	}
 
-	x = PyFloat_AsDouble(f);
+	x = IFUNC(PyFloat_AsDouble(f));
 	Py_DECREF(f);
 	if (PyErr_Occurred()) {
 		return NULL;
 	}
 
-	return PyComplex_FromDoubles(x, 0);
+	return PFUNC(PyComplex_FromDoubles(x, 0));
 }
 
 static PyObject *
@@ -4918,7 +5036,7 @@
         PyObject *result;                                            \
         uint32_t status = 0;                                         \
                                                                      \
-        if (!PyArg_ParseTuple(args, "OO", &v, &w)) {                 \
+        if (!FFUNC(0, PyArg_ParseTuple(args, "OO", &v, &w))) {                 \
                 return NULL;                                         \
         }                                                            \
                                                                      \
@@ -4953,7 +5071,7 @@
         PyObject *a, *b;                             \
         PyObject *result;                            \
                                                      \
-        if (!PyArg_ParseTuple(args, "OO", &v, &w)) { \
+        if (!FFUNC(0, PyArg_ParseTuple(args, "OO", &v, &w))) { \
                 return NULL;                         \
         }                                            \
                                                      \
@@ -4982,7 +5100,7 @@
         PyObject *result;                                                    \
         uint32_t status = 0;                                                 \
                                                                              \
-        if (!PyArg_ParseTuple(args, "OOO", &v, &w, &x)) {                    \
+        if (!FFUNC(0, PyArg_ParseTuple(args, "OOO", &v, &w, &x))) {                    \
                 return NULL;                                                 \
         }                                                                    \
                                                                              \
@@ -5075,7 +5193,7 @@
 		return NULL;
 	}
 
-	mpd_qcopy_abs(MPD(result), MPD(a), &status);
+	SFUNC(mpd_qcopy_abs, MPD(result), MPD(a), &status);
 	Py_DECREF(a);
 	if (dec_addstatus(context, status)) {
 		Py_DECREF(result);
@@ -5111,7 +5229,7 @@
 		return NULL;
 	}
 
-	mpd_qcopy_negate(MPD(result), MPD(a), &status);
+	SFUNC(mpd_qcopy_negate, MPD(result), MPD(a), &status);
 	Py_DECREF(a);
 	if (dec_addstatus(context, status)) {
 		Py_DECREF(result);
@@ -5135,7 +5253,7 @@
 	PyObject *result;
 	uint32_t status = 0;
 
-	if (!PyArg_ParseTuple(args, "OO", &v, &w)) {
+	if (!FFUNC(0, PyArg_ParseTuple(args, "OO", &v, &w))) {
 		return NULL;
 	}
 
@@ -5147,7 +5265,7 @@
 		return NULL;
 	}
 
-	mpd_qcopy_sign(MPD(result), MPD(a), MPD(b), &status);
+	SFUNC(mpd_qcopy_sign, MPD(result), MPD(a), MPD(b), &status);
 	Py_DECREF(a);
 	Py_DECREF(b);
 	if (dec_addstatus(context, status)) {
@@ -5202,7 +5320,7 @@
 	cp = mpd_class(MPD(a), CTX(context));
 	Py_DECREF(a);
 
-	return Py_BuildValue("s", cp);
+	return PFUNC(Py_BuildValue("s", cp));
 }
 
 static PyObject *
@@ -5214,7 +5332,7 @@
 	uint32_t status = 0;
 	PyObject *ret;
 
-	if (!PyArg_ParseTuple(args, "OO", &v, &w)) {
+	if (!FFUNC(0, PyArg_ParseTuple(args, "OO", &v, &w))) {
 		return NULL;
 	}
 
@@ -5241,7 +5359,7 @@
 		return NULL;
 	}
 
-	ret = Py_BuildValue("(OO)", q, r);
+	ret = PFUNC(Py_BuildValue("(OO)", q, r));
 	Py_DECREF(r);
 	Py_DECREF(q);
 	return ret;
@@ -5259,11 +5377,11 @@
 	s = mpd_to_sci(MPD(a), CtxCaps(context));
 	Py_DECREF(a);
 	if (s == NULL) {
-		PyErr_NoMemory();
+		PyErr_SetString(FailAPIException, "failapi");
 		return NULL;
 	}
 
-	result = PyUnicode_FromString(s);
+	result = PFUNC(PyUnicode_FromString(s));
 	mpd_free(s);
 
 	return result;
@@ -5281,11 +5399,11 @@
 	s = mpd_to_eng(MPD(a), CtxCaps(context));
 	Py_DECREF(a);
 	if (s == NULL) {
-		PyErr_NoMemory();
+		PyErr_SetString(FailAPIException, "failapi");
 		return NULL;
 	}
 
-	result = PyUnicode_FromString(s);
+	result = PFUNC(PyUnicode_FromString(s));
 	mpd_free(s);
 
 	return result;
@@ -5304,7 +5422,7 @@
 	PyObject *a, *b;
 	PyObject *result;
 
-	if (!PyArg_ParseTuple(args, "OO", &v, &w)) {
+	if (!FFUNC(0, PyArg_ParseTuple(args, "OO", &v, &w))) {
 		return NULL;
 	}
 
@@ -5482,6 +5600,10 @@
   { "setcontext", (PyCFunction)PyDec_SetCurrentContext, METH_O, doc_setcontext},
   { "localcontext", (PyCFunction)ctxmanager_new, METH_VARARGS, doc_localcontext},
   { "IEEEContext", (PyCFunction)ieee_context, METH_O, doc_ieee_context},
+  { "getfailpoint", get_failpoint, METH_NOARGS, NULL},
+  { "getapicalls", get_apicalls, METH_NOARGS, NULL},
+  { "setfailpoint", set_failpoint, METH_O, NULL},
+  { "setapicalls", set_apicalls, METH_O, NULL},
   { NULL, NULL, 1, NULL }
 };
 
@@ -5571,9 +5693,13 @@
 
 	/* Init libmpdec */
 	mpd_traphandler = dec_traphandler;
-	mpd_mallocfunc = PyMem_Malloc;
+	mpd_mallocfunc = mpd_malloc_fail;
+	/* If dec->alloc is greater that the requested size,
+	   mpd_realloc uses the old memory area if the actual
+	   call to realloc fails. This makes it difficult to
+	   generate failures reliably. */
 	mpd_reallocfunc = PyMem_Realloc;
-	mpd_callocfunc = mpd_callocfunc_em;
+	mpd_callocfunc = mpd_calloc_fail;
 	mpd_free = PyMem_Free;
 	mpd_setminalloc(4);
 
@@ -5636,8 +5762,13 @@
 	ASSIGN_PTR(DecimalException, PyErr_NewException(
 	                                 "cdecimal.DecimalException",
 	                                 PyExc_ArithmeticError, NULL));
+	ASSIGN_PTR(FailAPIException, PyErr_NewException(
+	                                 "decimal.FailAPIException",
+	                                 PyExc_BaseException, NULL));
 	Py_INCREF(DecimalException);
 	CHECK_INT(PyModule_AddObject(m, "DecimalException", DecimalException));
+	Py_INCREF(FailAPIException);
+	CHECK_INT(PyModule_AddObject(m, "FailAPIException", FailAPIException));
 
 	/* Add exceptions that correspond to IEEE signals */
 	for (cm = signal_map; cm->name != NULL; cm++) {