+/**
+ * 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));
+ }
+ }
+
+ 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)
+{
+ 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;
+
+ 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;
+ }
+
+ 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;
+ }
+
+ /*
+ * 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;
+ }
+
+ 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;