configure: add '-Wundef' to warning flags

[lttng-tools.git] / src / bin / lttng-sessiond / thread.h

/*
 * Copyright (C) 2018 Jérémie Galarneau <jeremie.galarneau@efficios.com>
 *
 * SPDX-License-Identifier: GPL-2.0-only
 *
 */

#include <stdbool.h>

#ifndef THREAD_H
#define THREAD_H

struct lttng_thread;

/* Main function of the new thread. */
typedef void *(*lttng_thread_entry_point)(void *);

/* Callback invoked to initiate the shutdown a thread. */
typedef bool (*lttng_thread_shutdown_cb)(void *);

/*
 * Callback invoked to clean-up the thread data.
 * Invoked when the thread is destroyed to ensure there is no
 * race between a use by the "thread shutdown callback" and
 * a use by the thread itself.
 */
typedef void (*lttng_thread_cleanup_cb)(void *);

/*
 * Returns a reference to the newly-created thread.
 * The shutdown and cleanup callbacks are optional.
 */
struct lttng_thread *lttng_thread_create(const char *name,
		lttng_thread_entry_point entry,
		lttng_thread_shutdown_cb shutdown,
		lttng_thread_cleanup_cb cleanup,
		void *thread_data);

bool lttng_thread_get(struct lttng_thread *thread);
void lttng_thread_put(struct lttng_thread *thread);

const char *lttng_thread_get_name(const struct lttng_thread *thread);

/*
 * Explicitly shutdown a thread. This function returns once the
 * thread has returned and been joined.
 *
 * It is invalid to call this function more than once on a thread.
 *
 * Returns true on success, false on error.
 */
bool lttng_thread_shutdown(struct lttng_thread *thread);

/*
 * Shutdown all orphaned threads (threads to which no external reference
 * exist).
 *
 * Returns once all orphaned threads have been joined.
 */
void lttng_thread_list_shutdown_orphans(void);

#endif /* THREAD_H */