X-Git-Url: https://sigrok.org/gitweb/?a=blobdiff_plain;f=type_decoder.c;h=231a8939b461ce6c1c09a26761f6b3e41e3aea28;hb=6120ff64d4096bcb32c8a42f06ff77d75a5326c2;hp=9ed3339d418593507b61c649f3a8f09fc4a3a127;hpb=04383ea876df72b7bd5c19854c30c81abdc0aa0c;p=libsigrokdecode.git

diff --git a/type_decoder.c b/type_decoder.c
index 9ed3339..231a893 100644
--- a/type_decoder.c
+++ b/type_decoder.c
@@ -529,14 +529,22 @@ static int set_new_condition_list(PyObject *self, PyObject *args)
 		return SRD_ERR;
 	}
 
-	/* Parse the argument of self.wait() into 'py_conds'. */
-	if (!PyArg_ParseTuple(args, "O", &py_conds)) {
+	/*
+	 * Parse the argument of self.wait() into 'py_conds', and check
+	 * the data type. The argument is optional, None is assumed in
+	 * its absence. None or an empty dict or an empty list mean that
+	 * there is no condition, and the next available sample shall
+	 * get returned to the caller.
+	 */
+	py_conds = Py_None;
+	if (!PyArg_ParseTuple(args, "|O", &py_conds)) {
 		/* Let Python raise this exception. */
 		return SRD_ERR;
 	}
-
-	/* Check whether 'py_conds' is a dict or a list. */
-	if (PyList_Check(py_conds)) {
+	if (py_conds == Py_None) {
+		/* 'py_conds' is None. */
+		return 9999;
+	} else if (PyList_Check(py_conds)) {
 		/* 'py_conds' is a list. */
 		py_conditionlist = py_conds;
 		num_conditions = PyList_Size(py_conditionlist);
@@ -585,9 +593,45 @@ static int set_new_condition_list(PyObject *self, PyObject *args)
 	return ret;
 }
 
+/**
+ * Create a SKIP condition list for condition-less .wait() calls.
+ *
+ * @param di Decoder instance.
+ * @param count Number of samples to skip.
+ *
+ * @retval SRD_OK The new condition list was set successfully.
+ * @retval SRD_ERR There was an error setting the new condition list.
+ *                 The contents of di->condition_list are undefined.
+ *
+ * This routine is a reduced and specialized version of the @ref
+ * set_new_condition_list() and @ref create_term_list() routines which
+ * gets invoked when .wait() was called without specifications for
+ * conditions. This minor duplication of the SKIP term list creation
+ * simplifies the logic and avoids the creation of expensive Python
+ * objects with "constant" values which the caller did not pass in the
+ * first place. It results in maximum sharing of match handling code
+ * paths.
+ */
+static int set_skip_condition(struct srd_decoder_inst *di, uint64_t count)
+{
+	struct srd_term *term;
+	GSList *term_list;
+
+	condition_list_free(di);
+	term = g_malloc0(sizeof(*term));
+	term->type = SRD_TERM_SKIP;
+	term->num_samples_to_skip = count;
+	term->num_samples_already_skipped = 0;
+	term_list = g_slist_append(NULL, term);
+	di->condition_list = g_slist_append(di->condition_list, term_list);
+
+	return SRD_OK;
+}
+
 static PyObject *Decoder_wait(PyObject *self, PyObject *args)
 {
 	int ret;
+	uint64_t skip_count;
 	unsigned int i;
 	gboolean found_match;
 	struct srd_decoder_inst *di;
@@ -607,10 +651,25 @@ static PyObject *Decoder_wait(PyObject *self, PyObject *args)
 		return NULL;
 	}
 	if (ret == 9999) {
-		/* Empty condition list, automatic match. */
-		PyObject_SetAttrString(di->py_inst, "matched", Py_None);
-		/* Leave self.samplenum unchanged (== di->abs_cur_samplenum). */
-		return get_current_pinvalues(di);
+		/*
+		 * Empty condition list, automatic match. Arrange for the
+		 * execution of regular match handling code paths such that
+		 * the next available sample is returned to the caller.
+		 * Make sure to skip one sample when "anywhere within the
+		 * stream", yet make sure to not skip sample number 0.
+		 */
+		if (di->abs_cur_samplenum)
+			skip_count = 1;
+		else if (!di->condition_list)
+			skip_count = 0;
+		else
+			skip_count = 1;
+		ret = set_skip_condition(di, skip_count);
+		if (ret < 0) {
+			srd_dbg("%s: %s: Cannot setup condition-less wait().",
+				di->inst_id, __func__);
+			return NULL;
+		}
 	}
 
 	while (1) {