thread: add interface to manage threads

Add an interface to create and join threads as well as change the
priority on the threads.

src/pipewire/meson.build

@@ -39,6 +39,7 @@ pipewire_headers = [
   'proxy.h',
   'resource.h',
   'stream.h',
+  'thread.h',
   'thread-loop.h',
   'type.h',
   'utils.h',
@@ -75,6 +76,7 @@ pipewire_sources = [
   'resource.c',
   'settings.c',
   'stream.c',
+  'thread.c',
   'thread-loop.c',
   'utils.c',
   'work-queue.c',

src/pipewire/thread.c

@@ -0,0 +1,118 @@
+/* PipeWire
+ *
+ * Copyright © 2021 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 <stdlib.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <pthread.h>
+
+#include <spa/utils/defs.h>
+#include <spa/utils/list.h>
+
+#include <pipewire/log.h>
+
+#include "thread.h"
+
+
+static struct pw_thread *impl_create(void *data,
+			const struct spa_dict *props,
+			void *(*start)(void*), void *arg)
+{
+	pthread_t pt;
+	int err;
+	if ((err = pthread_create(&pt, NULL, start, arg)) != 0) {
+		errno = err;
+		return NULL;
+	}
+	return (struct pw_thread*)pt;
+}
+
+static int impl_join(void *data, struct pw_thread *thread, void **retval)
+{
+	pthread_t pt = (pthread_t)thread;
+	return pthread_join(pt, retval);
+}
+
+static struct {
+	struct pw_thread_utils utils;
+	struct pw_thread_utils_methods methods;
+} default_impl = {
+	{ { PW_TYPE_INTERFACE_ThreadUtils,
+		 PW_VERSION_THREAD_UTILS,
+		 SPA_CALLBACKS_INIT(&default_impl.methods,
+				 &default_impl) } },
+	{ PW_VERSION_THREAD_UTILS_METHODS,
+            .create = impl_create,
+	    .join = impl_join, }
+};
+
+static struct pw_thread_utils *global_impl = &default_impl.utils;
+
+SPA_EXPORT
+void pw_thread_utils_set_impl(struct pw_thread_utils *impl)
+{
+	if (impl == NULL)
+		impl = &default_impl.utils;
+	global_impl = impl;
+}
+
+SPA_EXPORT
+struct pw_thread *pw_thread_utils_create(const struct spa_dict *props,
+		void *(*start_routine)(void*), void *arg)
+{
+	struct pw_thread *res = NULL;
+	spa_interface_call_res(&global_impl->iface,
+			struct pw_thread_utils_methods, res, create, 0,
+			props, start_routine, arg);
+	return res;
+}
+
+SPA_EXPORT
+int pw_thread_utils_join(struct pw_thread *thread, void **retval)
+{
+	int res = -ENOTSUP;
+	spa_interface_call_res(&global_impl->iface,
+			struct pw_thread_utils_methods, res, join, 0,
+			thread, retval);
+	return res;
+}
+
+SPA_EXPORT
+int pw_thread_utils_acquire_rt(struct pw_thread *thread, int priority)
+{
+	int res = -ENOTSUP;
+	spa_interface_call_res(&global_impl->iface,
+			struct pw_thread_utils_methods, res, acquire_rt, 0,
+			thread, priority);
+	return res;
+}
+
+SPA_EXPORT
+int pw_thread_utils_drop_rt(struct pw_thread *thread)
+{
+	int res = -ENOTSUP;
+	spa_interface_call_res(&global_impl->iface,
+			struct pw_thread_utils_methods, res, drop_rt, 0, thread);
+	return res;
+}

src/pipewire/thread.h

@@ -0,0 +1,76 @@
+/* PipeWire
+ *
+ * Copyright © 2021 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.
+ */
+
+#ifndef PIPEWIRE_THREAD_H
+#define PIPEWIRE_THREAD_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <string.h>
+#include <errno.h>
+
+#include <spa/utils/dict.h>
+#include <pipewire/type.h>
+
+/** \defgroup pw_thread Thread related functions
+ *
+ * \brief functions to manipulate threads
+ */
+
+#define PW_TYPE_INTERFACE_ThreadUtils	PW_TYPE_INFO_INTERFACE_BASE "ThreadUtils"
+
+struct pw_thread;
+
+#define PW_VERSION_THREAD_UTILS		0
+struct pw_thread_utils { struct spa_interface iface; };
+
+/** thread utils */
+struct pw_thread_utils_methods {
+#define PW_VERSION_THREAD_UTILS_METHODS	0
+	uint32_t version;
+
+	struct pw_thread * (*create) (void *data, const struct spa_dict *props,
+			void *(*start)(void*), void *arg);
+	int (*join)(void *data, struct pw_thread *thread, void **retval);
+
+	int (*acquire_rt) (void *data, struct pw_thread *thread, int priority);
+	int (*drop_rt) (void *data, struct pw_thread *thread);
+};
+
+void pw_thread_utils_set_impl(struct pw_thread_utils *impl);
+
+struct pw_thread *pw_thread_utils_create(const struct spa_dict *props,
+		void *(*start)(void*), void *arg);
+int pw_thread_utils_join(struct pw_thread *thread, void **retval);
+
+int pw_thread_utils_acquire_rt(struct pw_thread *thread, int priority);
+int pw_thread_utils_drop_rt(struct pw_thread *thread);
+
+#ifdef __cplusplus
+}  /* extern "C" */
+#endif
+
+#endif /* PIPEWIRE_THREAD_H */