spa: move thread to SPA support

It can be more generally useful eventually.

spa/include/spa/support/thread.h

@@ -0,0 +1,129 @@
+/* Simple Plugin API
+ *
+ * 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 SPA_THREAD_H
+#define SPA_THREAD_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <string.h>
+#include <errno.h>
+
+#include <spa/utils/defs.h>
+#include <spa/utils/dict.h>
+
+/**
+ * \addtogroup spa_support
+ * \{
+ */
+
+/** a thread object.
+ * This can be cast to a platform native thread, like pthread on posix systems
+ */
+#define SPA_TYPE_INFO_Thread		SPA_TYPE_INFO_POINTER_BASE "Thread"
+struct spa_thread;
+
+#define SPA_TYPE_INTERFACE_ThreadUtils	SPA_TYPE_INFO_INTERFACE_BASE "ThreadUtils"
+#define SPA_VERSION_THREAD_UTILS		0
+struct spa_thread_utils { struct spa_interface iface; };
+
+/** thread utils */
+struct spa_thread_utils_methods {
+#define SPA_VERSION_THREAD_UTILS_METHODS	0
+	uint32_t version;
+
+	/** create a new thread that runs \a start with \a arg */
+	struct spa_thread * (*create) (void *data, const struct spa_dict *props,
+			void *(*start)(void*), void *arg);
+	/** stop and join a thread */
+	int (*join)(void *data, struct spa_thread *thread, void **retval);
+
+	/** get realtime priority range for threads created with \a props */
+	int (*get_rt_range) (void *data, const struct spa_dict *props, int *min, int *max);
+	/** acquire realtime priority */
+	int (*acquire_rt) (void *data, struct spa_thread *thread, int priority);
+	/** drop realtime priority */
+	int (*drop_rt) (void *data, struct spa_thread *thread);
+};
+
+static inline struct spa_thread *spa_thread_utils_create(struct spa_thread_utils *o,
+		const struct spa_dict *props, void *(*start_routine)(void*), void *arg)
+{
+	struct spa_thread *res = NULL;
+	spa_interface_call_res(&o->iface,
+			struct spa_thread_utils_methods, res, create, 0,
+			props, start_routine, arg);
+	return res;
+}
+
+static inline int spa_thread_utils_join(struct spa_thread_utils *o,
+		struct spa_thread *thread, void **retval)
+{
+	int res = -ENOTSUP;
+	spa_interface_call_res(&o->iface,
+			struct spa_thread_utils_methods, res, join, 0,
+			thread, retval);
+	return res;
+}
+
+static inline int spa_thread_utils_get_rt_range(struct spa_thread_utils *o,
+		const struct spa_dict *props, int *min, int *max)
+{
+	int res = -ENOTSUP;
+	spa_interface_call_res(&o->iface,
+			struct spa_thread_utils_methods, res, get_rt_range, 0,
+			props, min, max);
+	return res;
+}
+
+static inline int spa_thread_utils_acquire_rt(struct spa_thread_utils *o,
+		struct spa_thread *thread, int priority)
+{
+	int res = -ENOTSUP;
+	spa_interface_call_res(&o->iface,
+			struct spa_thread_utils_methods, res, acquire_rt, 0,
+			thread, priority);
+	return res;
+}
+
+static inline int spa_thread_utils_drop_rt(struct spa_thread_utils *o,
+		struct spa_thread *thread)
+{
+	int res = -ENOTSUP;
+	spa_interface_call_res(&o->iface,
+			struct spa_thread_utils_methods, res, drop_rt, 0, thread);
+	return res;
+}
+
+/**
+ * \}
+ */
+
+#ifdef __cplusplus
+}  /* extern "C" */
+#endif
+
+#endif /* SPA_THREAD_H */