pw-profiler: add profiler tool

Add Profiler object and fields.
Add profiler extension API. It notifies Profiler objects with
real-time performance data.
Add module that implements the profiler extension.
Add pw-profiler tool that binds to the profiler API and dumps the
data into a log file, gnuplot files, a html page and a script to
generate svg graphs. This is almost the same as what JACK2
JackEngineProfiling does.

src/modules/module-profiler/protocol-native.c

@@ -0,0 +1,125 @@
+/* PipeWire
+ *
+ * Copyright © 2019 Wim Taymans
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ */
+
+#include <errno.h>
+
+#include <spa/pod/builder.h>
+#include <spa/pod/parser.h>
+#include <spa/utils/result.h>
+
+#include <pipewire/pipewire.h>
+
+#include <extensions/protocol-native.h>
+#include <extensions/profiler.h>
+
+static int profiler_proxy_marshal_add_listener(void *object,
+			struct spa_hook *listener,
+			const struct pw_profiler_events *events,
+			void *data)
+{
+	struct pw_proxy *proxy = object;
+	pw_proxy_add_object_listener(proxy, listener, events, data);
+	return 0;
+}
+
+static int profiler_demarshal_add_listener(void *object,
+			const struct pw_protocol_native_message *msg)
+{
+	return -ENOTSUP;
+}
+
+static int profiler_resource_marshal_profile(void *object, const struct spa_pod *pod)
+{
+	struct pw_resource *resource = object;
+	struct spa_pod_builder *b;
+
+	b = pw_protocol_native_begin_resource(resource, PW_PROFILER_EVENT_PROFILE, NULL);
+
+	spa_pod_builder_add_struct(b, SPA_POD_Pod(pod));
+
+	return pw_protocol_native_end_resource(resource, b);
+}
+
+static int profiler_proxy_demarshal_profile(void *object,
+		const struct pw_protocol_native_message *msg)
+{
+	struct pw_proxy *proxy = object;
+	struct spa_pod_parser prs;
+	struct spa_pod *pod;
+
+	spa_pod_parser_init(&prs, msg->data, msg->size);
+
+	if (spa_pod_parser_get_struct(&prs, SPA_POD_Pod(&pod)) < 0)
+		return -EINVAL;
+
+	pw_proxy_notify(proxy, struct pw_profiler_events, profile, 0, pod);
+	return 0;
+}
+
+
+static const struct pw_profiler_methods pw_protocol_native_profiler_client_method_marshal = {
+	PW_VERSION_PROFILER_METHODS,
+	.add_listener = &profiler_proxy_marshal_add_listener,
+};
+
+static const struct pw_protocol_native_demarshal
+pw_protocol_native_profiler_server_method_demarshal[PW_PROFILER_METHOD_NUM] =
+{
+	[PW_PROFILER_METHOD_ADD_LISTENER] = { &profiler_demarshal_add_listener, 0 },
+};
+
+static const struct pw_profiler_events pw_protocol_native_profiler_server_event_marshal = {
+	PW_VERSION_PROFILER_EVENTS,
+	.profile = &profiler_resource_marshal_profile,
+};
+
+static const struct pw_protocol_native_demarshal
+pw_protocol_native_profiler_client_event_demarshal[PW_PROFILER_EVENT_NUM] =
+{
+	[PW_PROFILER_EVENT_PROFILE] = { &profiler_proxy_demarshal_profile, 0 },
+};
+
+static const struct pw_protocol_marshal pw_protocol_native_profiler_marshal = {
+	PW_TYPE_INTERFACE_Profiler,
+	PW_VERSION_PROFILER,
+	0,
+	PW_PROFILER_METHOD_NUM,
+	PW_PROFILER_EVENT_NUM,
+	.client_marshal = &pw_protocol_native_profiler_client_method_marshal,
+	.server_demarshal = pw_protocol_native_profiler_server_method_demarshal,
+	.server_marshal = &pw_protocol_native_profiler_server_event_marshal,
+	.client_demarshal = pw_protocol_native_profiler_client_event_demarshal,
+};
+
+int pw_protocol_native_ext_profiler_init(struct pw_context *context)
+{
+	struct pw_protocol *protocol;
+
+	protocol = pw_context_find_protocol(context, PW_TYPE_INFO_PROTOCOL_Native);
+	if (protocol == NULL)
+		return -EPROTO;
+
+	pw_protocol_add_marshal(protocol, &pw_protocol_native_profiler_marshal);
+	return 0;
+}