type_decoder: update .samplenum before ending .wait() with EOFError

[libsigrokdecode.git] / type_decoder.c

diff --git a/type_decoder.c b/type_decoder.c
index 0a92a45df7b1510c98ede2c226779cf8d667c435..cf7ec8e7c383b40b502201e4034b4b9b98e0a8de 100644 (file)
--- a/type_decoder.c
+++ b/type_decoder.c
@@ -1089,6 +1089,27 @@ static PyObject *Decoder_wait(PyObject *self, PyObject *args)
                /* Signal the main thread that we handled all samples. */
                g_cond_signal(&di->handled_all_samples_cond);
 
+               /*
+                * When EOF was provided externally, communicate the
+                * Python EOFError exception to .decode() and return
+                * from the .wait() method call. This is motivated by
+                * the use of Python context managers, so that .decode()
+                * methods can "close" incompletely accumulated data
+                * when the sample data is exhausted.
+                */
+               if (di->communicate_eof) {
+                       /* Advance self.samplenum to the (absolute) last sample number. */
+                       py_samplenum = PyLong_FromUnsignedLongLong(di->abs_cur_samplenum);
+                       PyObject_SetAttrString(di->py_inst, "samplenum", py_samplenum);
+                       Py_DECREF(py_samplenum);
+                       /* Raise an EOFError Python exception. */
+                       srd_dbg("%s: %s: Raising EOF from wait().",
+                               di->inst_id, __func__);
+                       g_mutex_unlock(&di->data_mutex);
+                       PyErr_SetString(PyExc_EOFError, "samples exhausted");
+                       goto err;
+               }
+
                /*
                 * When termination of wait() and decode() was requested,
                 * then exit the loop after releasing the mutex.