node: make port for_each more powerful

Make an int return from pw_node_for_each_port() so that we can return
errors or early exit.
Add pw_port_for_each_param() to iterate params. And use this to collect
the formats.

src/modules/module-autolink.c

@@ -234,10 +234,10 @@ static void node_port_removed(void *data, struct pw_port *port)
 {
 }
 
-static bool on_node_port_added(void *data, struct pw_port *port)
+static int on_node_port_added(void *data, struct pw_port *port)
 {
 	node_port_added(data, port);
-	return true;
+	return 0;
 }
 
 static void on_node_created(struct pw_node *node, struct node_info *info)

src/modules/module-jack/jack-node.c

@@ -1067,16 +1067,16 @@ struct find_data {
 	struct pw_jack_port *result;
 };
 
-static bool find_port(void *data, struct pw_port *port)
+static int find_port(void *data, struct pw_port *port)
 {
 	struct find_data *d = data;
 	struct port_data *pd = pw_port_get_user_data(port);
 
 	if (pd->port.port_id == d->port_id) {
 		d->result = &pd->port;
-		return false;
+		return 1;
 	}
-	return true;
+	return 0;
 }
 
 struct pw_jack_port *
@@ -1085,7 +1085,7 @@ pw_jack_node_find_port(struct pw_jack_node *node,
 		       jack_port_id_t port_id)
 {
 	struct find_data data = { port_id, };
-	if (!pw_node_for_each_port(node->node, direction, find_port, &data))
+	if (pw_node_for_each_port(node->node, direction, find_port, &data) == 1)
 		return data.result;
 	return NULL;
 }

src/pipewire/node.c

@@ -219,49 +219,43 @@ static int update_port_ids(struct pw_node *node)
 	return 0;
 }
 
-static int collect_params(struct pw_port *port, uint32_t param_id, struct spa_pod ***result)
+struct param_array {
+	struct spa_pod **params;
+	uint32_t n_params;
+};
+
+static int add_param(void *data, struct spa_pod *param)
 {
-	int res;
-	uint8_t buffer[4096];
-	struct spa_pod_builder b = { 0 };
-	uint32_t state = 0;
+	struct param_array *arr = data;
+	uint32_t idx = arr->n_params++;
 
-	for (res = 0;; res++) {
-		struct spa_pod *fmt;
-
-		spa_pod_builder_init(&b, buffer, sizeof(buffer));
-		if (spa_node_port_enum_params(port->node->node,
-					      port->direction, port->port_id,
-					      param_id, &state,
-					      NULL, &fmt, &b) <= 0)
-			break;
-
-		*result = realloc(*result, sizeof(struct spa_pod *) * (res + 1));
-		(*result)[res] = pw_spa_pod_copy(fmt);
-	}
-	return res;
+	arr->params = realloc(arr->params, sizeof(struct spa_pod *) * arr->n_params);
+	arr->params[idx] = pw_spa_pod_copy(param);
+	return 0;
 }
 
 static void
 update_info(struct pw_node *this)
 {
 	struct pw_type *t = &this->core->type;
+	struct param_array params;
+	struct pw_port *port;
 
-	this->info.input_params = NULL;
+	params = (struct param_array) { NULL };
 	if (!spa_list_is_empty(&this->input_ports)) {
-		struct pw_port *port = spa_list_first(&this->input_ports, struct pw_port, link);
-		this->info.n_input_params = collect_params(port,
-							   t->param.idEnumFormat,
-							   &this->info.input_params);
+		port = spa_list_first(&this->input_ports, struct pw_port, link);
+		pw_port_for_each_param(port, t->param.idEnumFormat, NULL, add_param, &params);
 	}
+	this->info.input_params = params.params;
+	this->info.n_input_params = params.n_params;
 
-	this->info.output_params = NULL;
+	params = (struct param_array) { NULL };
 	if (!spa_list_is_empty(&this->output_ports)) {
-		struct pw_port *port = spa_list_first(&this->output_ports, struct pw_port, link);
-		this->info.n_output_params = collect_params(port,
-							    t->param.idEnumFormat,
-							    &this->info.output_params);
+		port = spa_list_first(&this->output_ports, struct pw_port, link);
+		pw_port_for_each_param(port, t->param.idEnumFormat, NULL, add_param, &params);
 	}
+	this->info.output_params = params.params;
+	this->info.n_output_params = params.n_params;
 }
 
 static void
@@ -614,13 +608,14 @@ void pw_node_destroy(struct pw_node *node)
 	free(impl);
 }
 
-bool pw_node_for_each_port(struct pw_node *node,
+int pw_node_for_each_port(struct pw_node *node,
 			  enum pw_direction direction,
-			   bool (*callback) (void *data, struct pw_port *port),
+			  int (*callback) (void *data, struct pw_port *port),
 			  void *data)
 {
 	struct spa_list *ports;
 	struct pw_port *p, *t;
+	int res;
 
 	if (direction == PW_DIRECTION_INPUT)
 		ports = &node->input_ports;
@@ -628,9 +623,9 @@ bool pw_node_for_each_port(struct pw_node *node,
 		ports = &node->output_ports;
 
 	spa_list_for_each_safe(p, t, ports, link)
-		if (!callback(data, p))
-			return false;
-	return true;
+		if ((res = callback(data, p)) != 0)
+			return res;
+	return 0;
 }
 
 struct pw_port *

src/pipewire/node.h

@@ -138,10 +138,13 @@ void pw_node_add_listener(struct pw_node *node,
 			  const struct pw_node_events *events,
 			  void *data);
 
-/** iterate the ports in the given direction */
-bool pw_node_for_each_port(struct pw_node *node,
+/** Iterate the ports in the given direction. The callback should return
+ * 0 to fetch the next item, any other value stops the iteration and returns
+ * the value. When all callbacks return 0, this function returns 0 when all
+ * items are iterated. */
+int pw_node_for_each_port(struct pw_node *node,
 			  enum pw_direction direction,
-			   bool (*callback) (void *data, struct pw_port *port),
+			  int (*callback) (void *data, struct pw_port *port),
 			  void *data);
 
 

src/pipewire/port.c

@@ -382,6 +382,33 @@ int pw_port_pause(struct pw_port *port)
 	return 0;
 }
 
+int pw_port_for_each_param(struct pw_port *port,
+			   uint32_t param_id,
+			   const struct spa_pod *filter,
+			   int (*callback) (void *data, struct spa_pod *param),
+			   void *data)
+{
+	int res;
+	uint8_t buffer[4096];
+	struct spa_pod_builder b = { 0 };
+	uint32_t state;
+	struct spa_pod *param;
+
+	for (state = 0;;) {
+		spa_pod_builder_init(&b, buffer, sizeof(buffer));
+		if ((res = spa_node_port_enum_params(port->node->node,
+						     port->direction,
+						     port->port_id,
+						     param_id, &state,
+						     filter, &param, &b)) <= 0)
+			break;
+
+		if ((res = callback(data, param)) != 0)
+			break;
+	}
+	return res;
+}
+
 int pw_port_set_param(struct pw_port *port, uint32_t id, uint32_t flags,
 		      const struct spa_pod *param)
 {

src/pipewire/private.h

@@ -429,6 +429,15 @@ bool pw_port_add(struct pw_port *port, struct pw_node *node);
 /** Destroy a port \memberof pw_port */
 void pw_port_destroy(struct pw_port *port);
 
+/** Iterate the params of the given port. The callback should return
+ * 1 to fetch the next item, 0 to stop iteration or <0 on error.
+ * The function returns 0 on success or the error returned by the callback. */
+int pw_port_for_each_param(struct pw_port *port,
+			   uint32_t param_id,
+			   const struct spa_pod *filter,
+			   int (*callback) (void *data, struct spa_pod *param),
+			   void *data);
+
 /** Set a param on a port \memberof pw_port */
 int pw_port_set_param(struct pw_port *port, uint32_t id, uint32_t flags,
 		      const struct spa_pod *param);