#ifndef KERNEL_FUTEX_H_
#define KERNEL_FUTEX_H_

#include <kernel/btree.h>
#include <kernel/wait.h>
#include <mango/types.h>

struct task;
struct address_space;

typedef uintptr_t futex_key_t;

struct futex {
	struct btree_node f_node;

	futex_key_t f_key;
	struct waitqueue f_waiters;
};

extern kern_status_t futex_init(void);
extern kern_status_t futex_get(
	kern_futex_t *futex,
	futex_key_t *out,
	unsigned int flags);
extern kern_status_t futex_wait(
	futex_key_t futex,
	kern_futex_t new_val,
	unsigned int flags);
extern kern_status_t futex_wake(
	futex_key_t futex,
	size_t nwaiters,
	unsigned int flags);

#endif