X-Git-Url: https://sigrok.org/gitweb/?p=libsigrokdecode.git;a=blobdiff_plain;f=type_decoder.c;h=6692c3d44e34c54960381aa56812748726e81406;hp=34b414e6c3b31a96644529245ea504d9dd665227;hb=3a67b032235e719dc4e74f735d1c95ef2d481a33;hpb=d0a0ed032e0120140a28e93ac42753786bf0087b

diff --git a/type_decoder.c b/type_decoder.c
index 34b414e..6692c3d 100644
--- a/type_decoder.c
+++ b/type_decoder.c
@@ -1,5 +1,5 @@
 /*
- * This file is part of the sigrok project.
+ * This file is part of the libsigrokdecode project.
  *
  * Copyright (C) 2012 Bert Vermeulen <bert@biot.com>
  *
@@ -17,178 +17,1050 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#include "sigrokdecode.h" /* First, so we avoid a _POSIX_C_SOURCE warning. */
-#include "sigrokdecode-internal.h"
-#include "config.h"
+#include <config.h>
+#include "libsigrokdecode-internal.h" /* First, so we avoid a _POSIX_C_SOURCE warning. */
+#include "libsigrokdecode.h"
+#include <inttypes.h>
 
+/** @cond PRIVATE */
+extern SRD_PRIV GSList *sessions;
+/** @endcond */
 
-static int convert_pyobj(struct srd_decoder_instance *di, PyObject *obj,
-		int *ann_format, char ***ann)
+typedef struct {
+        PyObject_HEAD
+} srd_Decoder;
+
+/* This is only used for nicer srd_dbg() output. */
+static const char *output_type_name(unsigned int idx)
+{
+	static const char names[][16] = {
+		"OUTPUT_ANN",
+		"OUTPUT_PYTHON",
+		"OUTPUT_BINARY",
+		"OUTPUT_META",
+		"(invalid)"
+	};
+
+	return names[MIN(idx, G_N_ELEMENTS(names) - 1)];
+}
+
+static void release_annotation(struct srd_proto_data_annotation *pda)
+{
+	if (!pda)
+		return;
+	if (pda->ann_text)
+		g_strfreev(pda->ann_text);
+}
+
+static int convert_annotation(struct srd_decoder_inst *di, PyObject *obj,
+		struct srd_proto_data *pdata)
 {
 	PyObject *py_tmp;
 	struct srd_pd_output *pdo;
-	int ann_id;
+	struct srd_proto_data_annotation *pda;
+	int ann_class;
+	char **ann_text;
+	PyGILState_STATE gstate;
+
+	gstate = PyGILState_Ensure();
 
-	/* Should be a list of [annotation format, [string, ...]] */
-	if (!PyList_Check(obj) && !PyTuple_Check(obj)) {
-		srd_err("Protocol decoder %s submitted %s instead of list",
-				di->decoder->name, obj->ob_type->tp_name);
-		return SRD_ERR_PYTHON;
+	/* Should be a list of [annotation class, [string, ...]]. */
+	if (!PyList_Check(obj)) {
+		srd_err("Protocol decoder %s submitted an annotation that"
+			" is not a list", di->decoder->name);
+		goto err;
 	}
 
-	/* Should have 2 elements... */
+	/* Should have 2 elements. */
 	if (PyList_Size(obj) != 2) {
-		srd_err("Protocol decoder %s submitted annotation list with %d elements instead of 2",
-				di->decoder->name, PyList_Size(obj));
-		return SRD_ERR_PYTHON;
+		srd_err("Protocol decoder %s submitted annotation list with "
+			"%zd elements instead of 2", di->decoder->name,
+			PyList_Size(obj));
+		goto err;
 	}
 
-	/* First element should be an integer matching a previously
-	 * registered annotation format. */
+	/*
+	 * The first element should be an integer matching a previously
+	 * registered annotation class.
+	 */
 	py_tmp = PyList_GetItem(obj, 0);
 	if (!PyLong_Check(py_tmp)) {
-		srd_err("Protocol decoder %s submitted annotation list, but first element was not an integer",
-				di->decoder->name);
-		return SRD_ERR_PYTHON;
+		srd_err("Protocol decoder %s submitted annotation list, but "
+			"first element was not an integer.", di->decoder->name);
+		goto err;
 	}
-
-	ann_id = PyLong_AsLong(py_tmp);
-	if (!(pdo = g_slist_nth_data(di->decoder->annotations, ann_id))) {
-		srd_err("Protocol decoder %s submitted data to non-existent annotation format %d",
-				di->decoder->name, ann_id);
-		return SRD_ERR_PYTHON;
+	ann_class = PyLong_AsLong(py_tmp);
+	if (!(pdo = g_slist_nth_data(di->decoder->annotations, ann_class))) {
+		srd_err("Protocol decoder %s submitted data to unregistered "
+			"annotation class %d.", di->decoder->name, ann_class);
+		goto err;
 	}
-	*ann_format = ann_id;
 
-	/* Second element must be a list */
+	/* Second element must be a list. */
 	py_tmp = PyList_GetItem(obj, 1);
 	if (!PyList_Check(py_tmp)) {
-		srd_err("Protocol decoder %s submitted annotation list, but second element was not a list",
-				di->decoder->name);
-		return SRD_ERR_PYTHON;
+		srd_err("Protocol decoder %s submitted annotation list, but "
+			"second element was not a list.", di->decoder->name);
+		goto err;
+	}
+	if (py_strseq_to_char(py_tmp, &ann_text) != SRD_OK) {
+		srd_err("Protocol decoder %s submitted annotation list, but "
+			"second element was malformed.", di->decoder->name);
+		goto err;
+	}
+
+	pda = pdata->data;
+	pda->ann_class = ann_class;
+	pda->ann_text = ann_text;
+
+	PyGILState_Release(gstate);
+
+	return SRD_OK;
+
+err:
+	PyGILState_Release(gstate);
+
+	return SRD_ERR_PYTHON;
+}
+
+static void release_binary(struct srd_proto_data_binary *pdb)
+{
+	if (!pdb)
+		return;
+	g_free((void *)pdb->data);
+}
+
+static int convert_binary(struct srd_decoder_inst *di, PyObject *obj,
+		struct srd_proto_data *pdata)
+{
+	struct srd_proto_data_binary *pdb;
+	PyObject *py_tmp;
+	Py_ssize_t size;
+	int bin_class;
+	char *class_name, *buf;
+	PyGILState_STATE gstate;
+
+	gstate = PyGILState_Ensure();
+
+	/* Should be a list of [binary class, bytes]. */
+	if (!PyList_Check(obj)) {
+		srd_err("Protocol decoder %s submitted non-list for SRD_OUTPUT_BINARY.",
+			di->decoder->name);
+		goto err;
+	}
+
+	/* Should have 2 elements. */
+	if (PyList_Size(obj) != 2) {
+		srd_err("Protocol decoder %s submitted SRD_OUTPUT_BINARY list "
+				"with %zd elements instead of 2", di->decoder->name,
+				PyList_Size(obj));
+		goto err;
+	}
+
+	/* The first element should be an integer. */
+	py_tmp = PyList_GetItem(obj, 0);
+	if (!PyLong_Check(py_tmp)) {
+		srd_err("Protocol decoder %s submitted SRD_OUTPUT_BINARY list, "
+			"but first element was not an integer.", di->decoder->name);
+		goto err;
+	}
+	bin_class = PyLong_AsLong(py_tmp);
+	if (!(class_name = g_slist_nth_data(di->decoder->binary, bin_class))) {
+		srd_err("Protocol decoder %s submitted SRD_OUTPUT_BINARY with "
+			"unregistered binary class %d.", di->decoder->name, bin_class);
+		goto err;
 	}
-	if (py_strlist_to_char(py_tmp, ann) != SRD_OK) {
-		srd_err("Protocol decoder %s submitted annotation list, but second element was malformed",
-				di->decoder->name);
-		return SRD_ERR_PYTHON;
+
+	/* Second element should be bytes. */
+	py_tmp = PyList_GetItem(obj, 1);
+	if (!PyBytes_Check(py_tmp)) {
+		srd_err("Protocol decoder %s submitted SRD_OUTPUT_BINARY list, "
+			"but second element was not bytes.", di->decoder->name);
+		goto err;
+	}
+
+	/* Consider an empty set of bytes a bug. */
+	if (PyBytes_Size(py_tmp) == 0) {
+		srd_err("Protocol decoder %s submitted SRD_OUTPUT_BINARY "
+				"with empty data set.", di->decoder->name);
+		goto err;
+	}
+
+	if (PyBytes_AsStringAndSize(py_tmp, &buf, &size) == -1)
+		goto err;
+
+	PyGILState_Release(gstate);
+
+	pdb = pdata->data;
+	pdb->bin_class = bin_class;
+	pdb->size = size;
+	if (!(pdb->data = g_try_malloc(pdb->size)))
+		return SRD_ERR_MALLOC;
+	memcpy((void *)pdb->data, (const void *)buf, pdb->size);
+
+	return SRD_OK;
+
+err:
+	PyGILState_Release(gstate);
+
+	return SRD_ERR_PYTHON;
+}
+
+static inline struct srd_decoder_inst *srd_sess_inst_find_by_obj(
+	struct srd_session *sess, const GSList *stack, const PyObject *obj)
+{
+	const GSList *l;
+	struct srd_decoder_inst *tmp, *di;
+
+	if (!sess)
+		return NULL;
+
+	di = NULL;
+	for (l = stack ? stack : sess->di_list; di == NULL && l != NULL; l = l->next) {
+		tmp = l->data;
+		if (tmp->py_inst == obj)
+			di = tmp;
+		else if (tmp->next_di)
+			di = srd_sess_inst_find_by_obj(sess, tmp->next_di, obj);
+	}
+
+	return di;
+}
+
+/**
+ * Find a decoder instance by its Python object.
+ *
+ * I.e. find that instance's instantiation of the sigrokdecode.Decoder class.
+ * This will recurse to find the instance anywhere in the stack tree of all
+ * sessions.
+ *
+ * @param stack Pointer to a GSList of struct srd_decoder_inst, indicating the
+ *              stack to search. To start searching at the bottom level of
+ *              decoder instances, pass NULL.
+ * @param obj The Python class instantiation.
+ *
+ * @return Pointer to struct srd_decoder_inst, or NULL if not found.
+ *
+ * @since 0.1.0
+ */
+static inline struct srd_decoder_inst *srd_inst_find_by_obj(
+		const GSList *stack, const PyObject *obj)
+{
+	struct srd_decoder_inst *di;
+	struct srd_session *sess;
+	GSList *l;
+
+	/* Performance shortcut: Handle the most common case first. */
+	sess = sessions->data;
+	di = sess->di_list->data;
+	if (di->py_inst == obj)
+		return di; 
+
+	di = NULL;
+	for (l = sessions; di == NULL && l != NULL; l = l->next) {
+		sess = l->data;
+		di = srd_sess_inst_find_by_obj(sess, stack, obj);
+	}
+
+	return di;
+}
+
+static int convert_meta(struct srd_proto_data *pdata, PyObject *obj)
+{
+	long long intvalue;
+	double dvalue;
+	PyGILState_STATE gstate;
+
+	gstate = PyGILState_Ensure();
+
+	if (g_variant_type_equal(pdata->pdo->meta_type, G_VARIANT_TYPE_INT64)) {
+		if (!PyLong_Check(obj)) {
+			PyErr_Format(PyExc_TypeError, "This output was registered "
+					"as 'int', but something else was passed.");
+			goto err;
+		}
+		intvalue = PyLong_AsLongLong(obj);
+		if (PyErr_Occurred())
+			goto err;
+		pdata->data = g_variant_new_int64(intvalue);
+	} else if (g_variant_type_equal(pdata->pdo->meta_type, G_VARIANT_TYPE_DOUBLE)) {
+		if (!PyFloat_Check(obj)) {
+			PyErr_Format(PyExc_TypeError, "This output was registered "
+					"as 'float', but something else was passed.");
+			goto err;
+		}
+		dvalue = PyFloat_AsDouble(obj);
+		if (PyErr_Occurred())
+			goto err;
+		pdata->data = g_variant_new_double(dvalue);
 	}
 
+	PyGILState_Release(gstate);
+
 	return SRD_OK;
+
+err:
+	PyGILState_Release(gstate);
+
+	return SRD_ERR_PYTHON;
+}
+
+static void release_meta(GVariant *gvar)
+{
+	if (!gvar)
+		return;
+	g_variant_unref(gvar);
 }
 
 static PyObject *Decoder_put(PyObject *self, PyObject *args)
 {
 	GSList *l;
-	PyObject *data, *py_res;
-	struct srd_decoder_instance *di, *next_di;
+	PyObject *py_data, *py_res;
+	struct srd_decoder_inst *di, *next_di;
 	struct srd_pd_output *pdo;
-	struct srd_proto_data *pdata;
+	struct srd_proto_data pdata;
+	struct srd_proto_data_annotation pda;
+	struct srd_proto_data_binary pdb;
 	uint64_t start_sample, end_sample;
 	int output_id;
-	void (*cb)();
+	struct srd_pd_callback *cb;
+	PyGILState_STATE gstate;
 
-	if (!(di = get_di_by_decobject(self)))
-		return NULL;
+	py_data = NULL;
 
-	if (!PyArg_ParseTuple(args, "KKiO", &start_sample, &end_sample, &output_id, &data))
-		return NULL;
+	gstate = PyGILState_Ensure();
+
+	if (!(di = srd_inst_find_by_obj(NULL, self))) {
+		/* Shouldn't happen. */
+		srd_dbg("put(): self instance not found.");
+		goto err;
+	}
+
+	if (!PyArg_ParseTuple(args, "KKiO", &start_sample, &end_sample,
+		&output_id, &py_data)) {
+		/*
+		 * This throws an exception, but by returning NULL here we let
+		 * Python raise it. This results in a much better trace in
+		 * controller.c on the decode() method call.
+		 */
+		goto err;
+	}
 
 	if (!(l = g_slist_nth(di->pd_output, output_id))) {
-		srd_err("Protocol decoder %s submitted invalid output ID %d",
-				di->decoder->name, output_id);
-		return NULL;
+		srd_err("Protocol decoder %s submitted invalid output ID %d.",
+			di->decoder->name, output_id);
+		goto err;
 	}
 	pdo = l->data;
 
-	if (!(pdata = g_try_malloc0(sizeof(struct srd_proto_data))))
-		return NULL;
-	pdata->start_sample = start_sample;
-	pdata->end_sample = end_sample;
-	pdata->pdo = pdo;
+	srd_spew("Instance %s put %" PRIu64 "-%" PRIu64 " %s on oid %d.",
+		 di->inst_id, start_sample, end_sample,
+		 output_type_name(pdo->output_type), output_id);
+
+	pdata.start_sample = start_sample;
+	pdata.end_sample = end_sample;
+	pdata.pdo = pdo;
+	pdata.data = NULL;
 
 	switch (pdo->output_type) {
 	case SRD_OUTPUT_ANN:
 		/* Annotations are only fed to callbacks. */
-		if ((cb = srd_find_callback(pdo->output_type))) {
-			/* Annotations need converting from PyObject. */
-			if (convert_pyobj(di, data, &pdata->ann_format,
-					(char ***)&pdata->data) != SRD_OK) {
+		if ((cb = srd_pd_output_callback_find(di->sess, pdo->output_type))) {
+			pdata.data = &pda;
+			/* Convert from PyDict to srd_proto_data_annotation. */
+			if (convert_annotation(di, py_data, &pdata) != SRD_OK) {
 				/* An error was already logged. */
 				break;
 			}
-			cb(pdata);
+			Py_BEGIN_ALLOW_THREADS
+			cb->cb(&pdata, cb->cb_data);
+			Py_END_ALLOW_THREADS
+			release_annotation(pdata.data);
 		}
 		break;
-	case SRD_OUTPUT_PROTO:
+	case SRD_OUTPUT_PYTHON:
 		for (l = di->next_di; l; l = l->next) {
 			next_di = l->data;
-			/* TODO: is this needed? */
-			Py_XINCREF(next_di->py_instance);
-			if (!(py_res = PyObject_CallMethod(next_di->py_instance, "decode",
-					"KKO", start_sample, end_sample, data))) {
-				if (PyErr_Occurred())
-					PyErr_Print();
+			srd_spew("Sending %" PRIu64 "-%" PRIu64 " to instance %s",
+				 start_sample, end_sample, next_di->inst_id);
+			if (!(py_res = PyObject_CallMethod(
+				next_di->py_inst, "decode", "KKO", start_sample,
+				end_sample, py_data))) {
+				srd_exception_catch("Calling %s decode() failed",
+							next_di->inst_id);
 			}
 			Py_XDECREF(py_res);
 		}
+		if ((cb = srd_pd_output_callback_find(di->sess, pdo->output_type))) {
+			/*
+			 * Frontends aren't really supposed to get Python
+			 * callbacks, but it's useful for testing.
+			 */
+			pdata.data = py_data;
+			cb->cb(&pdata, cb->cb_data);
+		}
 		break;
 	case SRD_OUTPUT_BINARY:
-		srd_err("SRD_OUTPUT_BINARY not yet supported");
+		if ((cb = srd_pd_output_callback_find(di->sess, pdo->output_type))) {
+			pdata.data = &pdb;
+			/* Convert from PyDict to srd_proto_data_binary. */
+			if (convert_binary(di, py_data, &pdata) != SRD_OK) {
+				/* An error was already logged. */
+				break;
+			}
+			Py_BEGIN_ALLOW_THREADS
+			cb->cb(&pdata, cb->cb_data);
+			Py_END_ALLOW_THREADS
+			release_binary(pdata.data);
+		}
+		break;
+	case SRD_OUTPUT_META:
+		if ((cb = srd_pd_output_callback_find(di->sess, pdo->output_type))) {
+			/* Annotations need converting from PyObject. */
+			if (convert_meta(&pdata, py_data) != SRD_OK) {
+				/* An exception was already set up. */
+				break;
+			}
+			Py_BEGIN_ALLOW_THREADS
+			cb->cb(&pdata, cb->cb_data);
+			Py_END_ALLOW_THREADS
+			release_meta(pdata.data);
+		}
 		break;
 	default:
-		srd_err("Protocol decoder %s submitted invalid output type %d",
-				di->decoder->name, pdo->output_type);
+		srd_err("Protocol decoder %s submitted invalid output type %d.",
+			di->decoder->name, pdo->output_type);
 		break;
 	}
 
-	g_free(pdata);
+	PyGILState_Release(gstate);
 
 	Py_RETURN_NONE;
+
+err:
+	PyGILState_Release(gstate);
+
+	return NULL;
+}
+
+static PyObject *Decoder_register(PyObject *self, PyObject *args,
+		PyObject *kwargs)
+{
+	struct srd_decoder_inst *di;
+	struct srd_pd_output *pdo;
+	PyObject *py_new_output_id;
+	PyTypeObject *meta_type_py;
+	const GVariantType *meta_type_gv;
+	int output_type;
+	char *proto_id, *meta_name, *meta_descr;
+	char *keywords[] = { "output_type", "proto_id", "meta", NULL };
+	PyGILState_STATE gstate;
+	gboolean is_meta;
+	GSList *l;
+	struct srd_pd_output *cmp;
+
+	gstate = PyGILState_Ensure();
+
+	meta_type_py = NULL;
+	meta_type_gv = NULL;
+	meta_name = meta_descr = NULL;
+
+	if (!(di = srd_inst_find_by_obj(NULL, self))) {
+		PyErr_SetString(PyExc_Exception, "decoder instance not found");
+		goto err;
+	}
+
+	/* Default to instance ID, which defaults to class ID. */
+	proto_id = di->inst_id;
+	if (!PyArg_ParseTupleAndKeywords(args, kwargs, "i|s(Oss)", keywords,
+			&output_type, &proto_id,
+			&meta_type_py, &meta_name, &meta_descr)) {
+		/* Let Python raise this exception. */
+		goto err;
+	}
+
+	/* Check if the meta value's type is supported. */
+	is_meta = output_type == SRD_OUTPUT_META;
+	if (is_meta) {
+		if (meta_type_py == &PyLong_Type)
+			meta_type_gv = G_VARIANT_TYPE_INT64;
+		else if (meta_type_py == &PyFloat_Type)
+			meta_type_gv = G_VARIANT_TYPE_DOUBLE;
+		else {
+			PyErr_Format(PyExc_TypeError, "Unsupported type.");
+			goto err;
+		}
+	}
+
+	pdo = NULL;
+	for (l = di->pd_output; l; l = l->next) {
+		cmp = l->data;
+		if (cmp->output_type != output_type)
+			continue;
+		if (strcmp(cmp->proto_id, proto_id) != 0)
+			continue;
+		if (is_meta && cmp->meta_type != meta_type_gv)
+			continue;
+		if (is_meta && strcmp(cmp->meta_name, meta_name) != 0)
+			continue;
+		if (is_meta && strcmp(cmp->meta_descr, meta_descr) != 0)
+			continue;
+		pdo = cmp;
+		break;
+	}
+	if (pdo) {
+		py_new_output_id = Py_BuildValue("i", pdo->pdo_id);
+		PyGILState_Release(gstate);
+		return py_new_output_id;
+	}
+
+	srd_dbg("Instance %s creating new output type %d for %s.",
+		di->inst_id, output_type, proto_id);
+
+	pdo = g_malloc(sizeof(struct srd_pd_output));
+
+	/* pdo_id is just a simple index, nothing is deleted from this list anyway. */
+	pdo->pdo_id = g_slist_length(di->pd_output);
+	pdo->output_type = output_type;
+	pdo->di = di;
+	pdo->proto_id = g_strdup(proto_id);
+
+	if (output_type == SRD_OUTPUT_META) {
+		pdo->meta_type = meta_type_gv;
+		pdo->meta_name = g_strdup(meta_name);
+		pdo->meta_descr = g_strdup(meta_descr);
+	}
+
+	di->pd_output = g_slist_append(di->pd_output, pdo);
+	py_new_output_id = Py_BuildValue("i", pdo->pdo_id);
+
+	PyGILState_Release(gstate);
+
+	return py_new_output_id;
+
+err:
+	PyGILState_Release(gstate);
+
+	return NULL;
+}
+
+static int get_term_type(const char *v)
+{
+	switch (v[0]) {
+	case 'h':
+		return SRD_TERM_HIGH;
+	case 'l':
+		return SRD_TERM_LOW;
+	case 'r':
+		return SRD_TERM_RISING_EDGE;
+	case 'f':
+		return SRD_TERM_FALLING_EDGE;
+	case 'e':
+		return SRD_TERM_EITHER_EDGE;
+	case 'n':
+		return SRD_TERM_NO_EDGE;
+	default:
+		return -1;
+	}
+
+	return -1;
 }
 
+/**
+ * Get the pin values at the current sample number.
+ *
+ * @param di The decoder instance to use. Must not be NULL.
+ *           The number of channels must be >= 1.
+ *
+ * @return A newly allocated PyTuple containing the pin values at the
+ *         current sample number.
+ */
+static PyObject *get_current_pinvalues(const struct srd_decoder_inst *di)
+{
+	int i;
+	uint8_t sample;
+	const uint8_t *sample_pos;
+	int byte_offset, bit_offset;
+	PyObject *py_pinvalues;
+	PyGILState_STATE gstate;
+
+	if (!di) {
+		srd_err("Invalid decoder instance.");
+		return NULL;
+	}
+
+	gstate = PyGILState_Ensure();
+
+	py_pinvalues = PyTuple_New(di->dec_num_channels);
+
+	for (i = 0; i < di->dec_num_channels; i++) {
+		/* A channelmap value of -1 means "unused optional channel". */
+		if (di->dec_channelmap[i] == -1) {
+			/* Value of unused channel is 0xff, instead of 0 or 1. */
+			PyTuple_SetItem(py_pinvalues, i, PyLong_FromLong(0xff));
+		} else {
+			sample_pos = di->inbuf + ((di->abs_cur_samplenum - di->abs_start_samplenum) * di->data_unitsize);
+			byte_offset = di->dec_channelmap[i] / 8;
+			bit_offset = di->dec_channelmap[i] % 8;
+			sample = *(sample_pos + byte_offset) & (1 << bit_offset) ? 1 : 0;
+			PyTuple_SetItem(py_pinvalues, i, PyLong_FromLong(sample));
+		}
+	}
 
-static PyObject *Decoder_add(PyObject *self, PyObject *args)
+	PyGILState_Release(gstate);
+
+	return py_pinvalues;
+}
+
+/**
+ * Create a list of terms in the specified condition.
+ *
+ * If there are no terms in the condition, 'term_list' will be NULL.
+ *
+ * @param py_dict A Python dict containing terms. Must not be NULL.
+ * @param term_list Pointer to a GSList which will be set to the newly
+ *                  created list of terms. Must not be NULL.
+ *
+ * @return SRD_OK upon success, a negative error code otherwise.
+ */
+static int create_term_list(PyObject *py_dict, GSList **term_list)
 {
-	PyObject *ret;
-	struct srd_decoder_instance *di;
-	char *proto_id;
-	int output_type, pdo_id;
+	Py_ssize_t pos = 0;
+	PyObject *py_key, *py_value;
+	struct srd_term *term;
+	uint64_t num_samples_to_skip;
+	char *term_str;
+	PyGILState_STATE gstate;
+
+	if (!py_dict || !term_list)
+		return SRD_ERR_ARG;
+
+	/* "Create" an empty GSList of terms. */
+	*term_list = NULL;
 
-	if (!(di = get_di_by_decobject(self))) {
-		srd_err("%s():%d decoder instance not found", __func__, __LINE__);
+	gstate = PyGILState_Ensure();
+
+	/* Iterate over all items in the current dict. */
+	while (PyDict_Next(py_dict, &pos, &py_key, &py_value)) {
+		/* Check whether the current key is a string or a number. */
+		if (PyLong_Check(py_key)) {
+			/* The key is a number. */
+			/* TODO: Check if the number is a valid channel. */
+			/* Get the value string. */
+			if ((py_pydictitem_as_str(py_dict, py_key, &term_str)) != SRD_OK) {
+				srd_err("Failed to get the value.");
+				goto err;
+			}
+			term = g_malloc(sizeof(struct srd_term));
+			term->type = get_term_type(term_str);
+			term->channel = PyLong_AsLong(py_key);
+			g_free(term_str);
+		} else if (PyUnicode_Check(py_key)) {
+			/* The key is a string. */
+			/* TODO: Check if it's "skip". */
+			if ((py_pydictitem_as_long(py_dict, py_key, &num_samples_to_skip)) != SRD_OK) {
+				srd_err("Failed to get number of samples to skip.");
+				goto err;
+			}
+			term = g_malloc(sizeof(struct srd_term));
+			term->type = SRD_TERM_SKIP;
+			term->num_samples_to_skip = num_samples_to_skip;
+			term->num_samples_already_skipped = 0;
+		} else {
+			srd_err("Term key is neither a string nor a number.");
+			goto err;
+		}
+
+		/* Add the term to the list of terms. */
+		*term_list = g_slist_append(*term_list, term);
+	}
+
+	PyGILState_Release(gstate);
+
+	return SRD_OK;
+
+err:
+	PyGILState_Release(gstate);
+
+	return SRD_ERR;
+}
+
+/**
+ * Replace the current condition list with the new one.
+ *
+ * @param self TODO. Must not be NULL.
+ * @param args TODO. Must not be NULL.
+ *
+ * @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.
+ * @retval 9999 TODO.
+ */
+static int set_new_condition_list(PyObject *self, PyObject *args)
+{
+	struct srd_decoder_inst *di;
+	GSList *term_list;
+	PyObject *py_conditionlist, *py_conds, *py_dict;
+	int i, num_conditions, ret;
+	PyGILState_STATE gstate;
+
+	if (!self || !args)
+		return SRD_ERR_ARG;
+
+	gstate = PyGILState_Ensure();
+
+	/* Get the decoder instance. */
+	if (!(di = srd_inst_find_by_obj(NULL, self))) {
 		PyErr_SetString(PyExc_Exception, "decoder instance not found");
+		goto err;
+	}
+
+	/*
+	 * Return an error condition from .wait() when termination is
+	 * requested, such that decode() will terminate.
+	 */
+	if (di->want_wait_terminate) {
+		srd_dbg("%s: %s: Skip (want_term).", di->inst_id, __func__);
+		goto err;
+	}
+
+	/*
+	 * 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. */
+		goto err;
+	}
+	if (py_conds == Py_None) {
+		/* 'py_conds' is None. */
+		goto ret_9999;
+	} else if (PyList_Check(py_conds)) {
+		/* 'py_conds' is a list. */
+		py_conditionlist = py_conds;
+		num_conditions = PyList_Size(py_conditionlist);
+		if (num_conditions == 0)
+			goto ret_9999; /* The PD invoked self.wait([]). */
+		Py_IncRef(py_conditionlist);
+	} else if (PyDict_Check(py_conds)) {
+		/* 'py_conds' is a dict. */
+		if (PyDict_Size(py_conds) == 0)
+			goto ret_9999; /* The PD invoked self.wait({}). */
+		/* Make a list and put the dict in there for convenience. */
+		py_conditionlist = PyList_New(1);
+		Py_IncRef(py_conds);
+		PyList_SetItem(py_conditionlist, 0, py_conds);
+		num_conditions = 1;
+	} else {
+		srd_err("Condition list is neither a list nor a dict.");
+		goto err;
+	}
+
+	/* Free the old condition list. */
+	condition_list_free(di);
+
+	ret = SRD_OK;
+
+	/* Iterate over the conditions, set di->condition_list accordingly. */
+	for (i = 0; i < num_conditions; i++) {
+		/* Get a condition (dict) from the condition list. */
+		py_dict = PyList_GetItem(py_conditionlist, i);
+		if (!PyDict_Check(py_dict)) {
+			srd_err("Condition is not a dict.");
+			ret = SRD_ERR;
+			break;
+		}
+
+		/* Create the list of terms in this condition. */
+		if ((ret = create_term_list(py_dict, &term_list)) < 0)
+			break;
+
+		/* Add the new condition to the PD instance's condition list. */
+		di->condition_list = g_slist_append(di->condition_list, term_list);
+	}
+
+	Py_DecRef(py_conditionlist);
+
+	PyGILState_Release(gstate);
+
+	return ret;
+
+err:
+	PyGILState_Release(gstate);
+
+	return SRD_ERR;
+
+ret_9999:
+	PyGILState_Release(gstate);
+
+	return 9999;
+}
+
+/**
+ * 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_malloc(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;
+	PyObject *py_pinvalues, *py_matched;
+	PyGILState_STATE gstate;
+
+	if (!self || !args)
 		return NULL;
+
+	gstate = PyGILState_Ensure();
+
+	if (!(di = srd_inst_find_by_obj(NULL, self))) {
+		PyErr_SetString(PyExc_Exception, "decoder instance not found");
+		PyGILState_Release(gstate);
+		Py_RETURN_NONE;
 	}
 
-	if (!PyArg_ParseTuple(args, "is", &output_type, &proto_id)) {
-		if (PyErr_Occurred())
-			PyErr_Print();
+	ret = set_new_condition_list(self, args);
+	if (ret < 0) {
+		srd_dbg("%s: %s: Aborting wait().", di->inst_id, __func__);
+		goto err;
+	}
+	if (ret == 9999) {
+		/*
+		 * 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__);
+			goto err;
+		}
+	}
+
+	while (1) {
+
+		Py_BEGIN_ALLOW_THREADS
+
+		/* Wait for new samples to process, or termination request. */
+		g_mutex_lock(&di->data_mutex);
+		while (!di->got_new_samples && !di->want_wait_terminate)
+			g_cond_wait(&di->got_new_samples_cond, &di->data_mutex);
+
+		/*
+		 * Check whether any of the current condition(s) match.
+		 * Arrange for termination requests to take a code path which
+		 * won't find new samples to process, pretends to have processed
+		 * previously stored samples, and returns to the main thread,
+		 * while the termination request still gets signalled.
+		 */
+		found_match = FALSE;
+
+		/* Ignore return value for now, should never be negative. */
+		(void)process_samples_until_condition_match(di, &found_match);
+
+		Py_END_ALLOW_THREADS
+
+		/* If there's a match, set self.samplenum etc. and return. */
+		if (found_match) {
+			/* Set self.samplenum to the (absolute) sample number that matched. */
+			PyObject_SetAttrString(di->py_inst, "samplenum",
+				PyLong_FromLong(di->abs_cur_samplenum));
+
+			if (di->match_array && di->match_array->len > 0) {
+				py_matched = PyTuple_New(di->match_array->len);
+				for (i = 0; i < di->match_array->len; i++)
+					PyTuple_SetItem(py_matched, i, PyBool_FromLong(di->match_array->data[i]));
+				PyObject_SetAttrString(di->py_inst, "matched", py_matched);
+				match_array_free(di);
+			} else {
+				PyObject_SetAttrString(di->py_inst, "matched", Py_None);
+			}
+
+			py_pinvalues = get_current_pinvalues(di);
+
+			g_mutex_unlock(&di->data_mutex);
+
+			PyGILState_Release(gstate);
+
+			return py_pinvalues;
+		}
+
+		/* No match, reset state for the next chunk. */
+		di->got_new_samples = FALSE;
+		di->handled_all_samples = TRUE;
+		di->abs_start_samplenum = 0;
+		di->abs_end_samplenum = 0;
+		di->inbuf = NULL;
+		di->inbuflen = 0;
+
+		/* Signal the main thread that we handled all samples. */
+		g_cond_signal(&di->handled_all_samples_cond);
+
+		/*
+		 * When termination of wait() and decode() was requested,
+		 * then exit the loop after releasing the mutex.
+		 */
+		if (di->want_wait_terminate) {
+			srd_dbg("%s: %s: Will return from wait().",
+				di->inst_id, __func__);
+			g_mutex_unlock(&di->data_mutex);
+			goto err;
+		}
+
+		g_mutex_unlock(&di->data_mutex);
+	}
+
+	PyGILState_Release(gstate);
+
+	Py_RETURN_NONE;
+
+err:
+	PyGILState_Release(gstate);
+
+	return NULL;
+}
+
+/**
+ * Return whether the specified channel was supplied to the decoder.
+ *
+ * @param self TODO. Must not be NULL.
+ * @param args TODO. Must not be NULL.
+ *
+ * @retval Py_True The channel has been supplied by the frontend.
+ * @retval Py_False The channel has been supplied by the frontend.
+ * @retval NULL An error occurred.
+ */
+static PyObject *Decoder_has_channel(PyObject *self, PyObject *args)
+{
+	int idx, count;
+	struct srd_decoder_inst *di;
+	PyGILState_STATE gstate;
+
+	if (!self || !args)
 		return NULL;
+
+	gstate = PyGILState_Ensure();
+
+	if (!(di = srd_inst_find_by_obj(NULL, self))) {
+		PyErr_SetString(PyExc_Exception, "decoder instance not found");
+		goto err;
 	}
 
-	pdo_id = pd_add(di, output_type, proto_id);
-	if (pdo_id < 0)
-		Py_RETURN_NONE;
-	else
-		ret = Py_BuildValue("i", pdo_id);
+	/*
+	 * Get the integer argument of self.has_channel(). Check for
+	 * the range of supported PD input channel numbers.
+	 */
+	if (!PyArg_ParseTuple(args, "i", &idx)) {
+		/* Let Python raise this exception. */
+		goto err;
+	}
 
-	return ret;
+	count = g_slist_length(di->decoder->channels) +
+	        g_slist_length(di->decoder->opt_channels);
+	if (idx < 0 || idx >= count) {
+		srd_err("Invalid index %d, PD channel count %d.", idx, count);
+		PyErr_SetString(PyExc_IndexError, "invalid channel index");
+		goto err;
+	}
+
+	PyGILState_Release(gstate);
+
+	return (di->dec_channelmap[idx] == -1) ? Py_False : Py_True;
+
+err:
+	PyGILState_Release(gstate);
+
+	return NULL;
 }
 
 static PyMethodDef Decoder_methods[] = {
-	{"put", Decoder_put, METH_VARARGS,
-	 "Accepts a dictionary with the following keys: time, duration, data"},
-	{"add", Decoder_add, METH_VARARGS, "Create a new output stream"},
+	{ "put", Decoder_put, METH_VARARGS,
+	  "Accepts a dictionary with the following keys: startsample, endsample, data" },
+	{ "register", (PyCFunction)Decoder_register, METH_VARARGS|METH_KEYWORDS,
+			"Register a new output stream" },
+	{ "wait", Decoder_wait, METH_VARARGS,
+			"Wait for one or more conditions to occur" },
+	{ "has_channel", Decoder_has_channel, METH_VARARGS,
+			"Report whether a channel was supplied" },
 	{NULL, NULL, 0, NULL}
 };
 
+/**
+ * Create the sigrokdecode.Decoder type.
+ *
+ * @return The new type object.
+ *
+ * @private
+ */
+SRD_PRIV PyObject *srd_Decoder_type_new(void)
+{
+	PyType_Spec spec;
+	PyType_Slot slots[] = {
+		{ Py_tp_doc, "sigrok Decoder base class" },
+		{ Py_tp_methods, Decoder_methods },
+		{ Py_tp_new, (void *)&PyType_GenericNew },
+		{ 0, NULL }
+	};
+	PyObject *py_obj;
+	PyGILState_STATE gstate;
 
-PyTypeObject srd_Decoder_type = {
-	PyVarObject_HEAD_INIT(NULL, 0)
-	.tp_name = "sigrokdecode.Decoder",
-	.tp_basicsize = sizeof(srd_Decoder),
-	.tp_flags = Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE,
-	.tp_doc = "Sigrok Decoder base class",
-	.tp_methods = Decoder_methods,
-};
+	gstate = PyGILState_Ensure();
 
+	spec.name = "sigrokdecode.Decoder";
+	spec.basicsize = sizeof(srd_Decoder);
+	spec.itemsize = 0;
+	spec.flags = Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE;
+	spec.slots = slots;
+
+	py_obj = PyType_FromSpec(&spec);
+
+	PyGILState_Release(gstate);
+
+	return py_obj;
+}