pulse-server: add skeleton extension for stream-restore

Makes the system-volume slider show up again in pavucontrol
and gnome-control-setting. Does not work yet, though.

src/modules/module-protocol-pulse/ext-stream-restore.c

@@ -0,0 +1,91 @@
+/* PipeWire
+ *
+ * Copyright © 2020 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.
+ */
+
+#define EXT_STREAM_RESTORE_VERSION	1
+
+static const struct extension_sub ext_stream_restore[];
+
+static int do_extension_stream_restore_test(struct client *client, uint32_t command, uint32_t tag, struct message *m)
+{
+	struct message *reply;
+
+	reply = reply_new(client, tag);
+	message_put(reply,
+			TAG_U32, EXT_STREAM_RESTORE_VERSION,
+			TAG_INVALID);
+	return send_message(client, reply);
+}
+
+static int do_extension_stream_restore_read(struct client *client, uint32_t command, uint32_t tag, struct message *m)
+{
+	struct message *reply;
+	reply = reply_new(client, tag);
+	return send_message(client, reply);
+}
+
+static int do_extension_stream_restore_write(struct client *client, uint32_t command, uint32_t tag, struct message *m)
+{
+	return reply_simple_ack(client, tag);
+}
+
+static int do_extension_stream_restore_delete(struct client *client, uint32_t command, uint32_t tag, struct message *m)
+{
+	return reply_simple_ack(client, tag);
+}
+
+static int do_extension_stream_restore_subscribe(struct client *client, uint32_t command, uint32_t tag, struct message *m)
+{
+	return reply_simple_ack(client, tag);
+}
+
+static const struct extension_sub ext_stream_restore[] = {
+	{ "TEST", 0, do_extension_stream_restore_test, },
+	{ "READ", 1, do_extension_stream_restore_read, },
+	{ "WRITE", 2, do_extension_stream_restore_write, },
+	{ "DELETE", 3, do_extension_stream_restore_delete, },
+	{ "SUBSCRIBE", 4, do_extension_stream_restore_subscribe, },
+	{ "EVENT", 5, },
+};
+
+static int do_extension_stream_restore(struct client *client, uint32_t tag, struct message *m)
+{
+	struct impl *impl = client->impl;
+	uint32_t command;
+	int res;
+
+	if ((res = message_get(m,
+			TAG_U32, &command,
+			TAG_INVALID)) < 0)
+		return -EPROTO;
+
+	if (command >= SPA_N_ELEMENTS(ext_stream_restore))
+		return -ENOTSUP;
+	if (ext_stream_restore[command].process == NULL)
+		return -EPROTO;
+
+	pw_log_info(NAME" %p: [EXT_STREAM_RESTORE_%s] %s tag:%u", impl, client->name,
+			ext_stream_restore[command].name, tag);
+
+	return ext_stream_restore[command].process(client, command, tag, m);
+}

src/modules/module-protocol-pulse/extension.c

@@ -0,0 +1,64 @@
+/* PipeWire
+ *
+ * Copyright © 2020 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.
+ */
+
+struct extension_sub {
+	const char *name;
+	uint32_t command;
+	int (*process)(struct client *client, uint32_t command, uint32_t tag, struct message *m);
+};
+
+struct extension {
+	const char *name;
+	uint32_t idx;
+	int (*process)(struct client *client, uint32_t tag, struct message *m);
+};
+
+#include "ext-stream-restore.c"
+
+static int do_extension_device_restore(struct client *client, uint32_t tag, struct message *m)
+{
+	return -ENOTSUP;
+}
+
+static int do_extension_device_manager(struct client *client, uint32_t tag, struct message *m)
+{
+	return -ENOTSUP;
+}
+
+struct extension extensions[] = {
+	{ "module-stream-restore", 0 | EXTENSION_FLAG, do_extension_stream_restore, },
+	{ "module-device-restore", 1 | EXTENSION_FLAG, do_extension_device_restore, },
+	{ "module-device-manager", 2 | EXTENSION_FLAG, do_extension_device_manager, },
+};
+
+static struct extension *find_extension(uint32_t idx, const char *name)
+{
+	uint32_t i;
+	for (i = 0; i < SPA_N_ELEMENTS(extensions); i++) {
+		if (idx == extensions[i].idx ||
+		    (name && strcmp(name, extensions[i].name) == 0))
+			return &extensions[i];
+	}
+	return 0;
+}

src/modules/module-protocol-pulse/pulse-server.c

@@ -420,6 +420,8 @@ static int reply_error(struct client *client, uint32_t command, uint32_t tag, in
 	return send_message(client, reply);
 }
 
+#include "extension.c"
+
 static int send_underflow(struct stream *stream, int64_t offset)
 {
 	struct client *client = stream->client;
@@ -4015,6 +4017,34 @@ static int do_update_stream_sample_rate(struct client *client, uint32_t command,
 	return reply_simple_ack(client, tag);
 }
 
+static int do_extension(struct client *client, uint32_t command, uint32_t tag, struct message *m)
+{
+	struct impl *impl = client->impl;
+	uint32_t idx;
+	const char *name;
+	struct extension *ext;
+	int res;
+
+	if ((res = message_get(m,
+			TAG_U32, &idx,
+			TAG_STRING, &name,
+			TAG_INVALID)) < 0)
+		return -EPROTO;
+
+	pw_log_info(NAME" %p: [%s] %s tag:%u id:%u name:%s", impl, client->name,
+			commands[command].name, tag, idx, name);
+
+	if ((idx == SPA_ID_INVALID && name == NULL) ||
+	    (idx != SPA_ID_INVALID && name != NULL))
+		return -EINVAL;
+
+	ext = find_extension(idx, name);
+	if (ext == NULL)
+		return -ENOENT;
+
+	return ext->process(client, tag, m);
+}
+
 static int do_set_profile(struct client *client, uint32_t command, uint32_t tag, struct message *m)
 {
 	struct impl *impl = client->impl;
@@ -4432,7 +4462,7 @@ static const struct command commands[COMMAND_MAX] =
 	[COMMAND_STARTED] = { "STARTED", },
 
 	/* Supported since protocol v14 (0.9.12) */
-	[COMMAND_EXTENSION] = { "EXTENSION", do_error_not_implemented, },
+	[COMMAND_EXTENSION] = { "EXTENSION", do_extension, },
 	/* Supported since protocol v15 (0.9.15) */
 	[COMMAND_SET_CARD_PROFILE] = { "SET_CARD_PROFILE", do_set_profile, },