/*	$OpenBSD: rthread.h,v 1.49 2014/07/01 03:32:18 guenther Exp $ */
/*
 * Copyright (c) 2004,2005 Ted Unangst <tedu@openbsd.org>
 * All Rights Reserved.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */
/*
 * Private data structures that back up the typedefs in pthread.h.
 * Since only the thread library cares about their size or arrangement,
 * it should be possible to switch libraries without relinking.
 *
 * Do not reorder struct _spinlock and sem_t variables in the structs.
 * This is due to alignment requirements of certain arches like hppa.
 * The current requirement is 16 bytes.
 *
 * THE MACHINE DEPENDENT CERROR CODE HAS HARD CODED OFFSETS INTO PTHREAD_T!
 */

#include <sys/queue.h>
#include <semaphore.h>
#include <machine/spinlock.h>
#include <machine/tcb.h>		/* for TLS_VARIANT */

#ifdef __LP64__
#define RTHREAD_STACK_SIZE_DEF (512 * 1024)
#else
#define RTHREAD_STACK_SIZE_DEF (256 * 1024)
#endif

#define _USING_TICKETS 0
/*
 * tickets don't work yet? (or seem much slower, with lots of system time)
 * until then, keep the struct around to avoid excessive changes going
 * back and forth.
 */
struct _spinlock {
	_atomic_lock_t ticket;
};

#define	_SPINLOCK_UNLOCKED { _ATOMIC_LOCK_UNLOCKED }
extern struct _spinlock _SPINLOCK_UNLOCKED_ASSIGN;

struct stack {
	SLIST_ENTRY(stack)	link;	/* link for free default stacks */
	void	*sp;			/* machine stack pointer */
	void	*base;			/* bottom of allocated area */
	size_t	guardsize;		/* size of PROT_NONE zone or */
					/* ==1 if application alloced */
	size_t	len;			/* total size of allocated stack */
};

struct __sem {
	struct _spinlock lock;
	volatile int waitcount;
	volatile int value;
	int shared;
};

TAILQ_HEAD(pthread_queue, pthread);

struct pthread_mutex {
	struct _spinlock lock;
	struct pthread_queue lockers;
	int type;
	pthread_t owner;
	int count;
	int prioceiling;
};

struct pthread_mutex_attr {
	int ma_type;
	int ma_protocol;
	int ma_prioceiling;
};

struct pthread_cond {
	struct _spinlock lock;
	struct pthread_queue waiters;
	struct pthread_mutex *mutex;
	clockid_t clock;
};

struct pthread_cond_attr {
	clockid_t ca_clock;
};

struct pthread_rwlock {
	struct _spinlock lock;
	pthread_t owner;
	struct pthread_queue writers;
	int readers;
};

struct pthread_rwlockattr {
	int pshared;
};

struct pthread_attr {
	void *stack_addr;
	size_t stack_size;
	size_t guard_size;
	int detach_state;
	int contention_scope;
	int sched_policy;
	struct sched_param sched_param;
	int sched_inherit;
};

#define	PTHREAD_MIN_PRIORITY	0
#define	PTHREAD_MAX_PRIORITY	31

struct rthread_key {
	int used;
	void (*destructor)(void *);
};

struct rthread_storage {
	int keyid;
	struct rthread_storage *next;
	void *data;
};

struct rthread_cleanup_fn {
	void (*fn)(void *);
	void *arg;
	struct rthread_cleanup_fn *next;
};

struct pthread_barrier {
	pthread_mutex_t mutex;
	pthread_cond_t cond;
	int threshold;
	int sofar;
	int generation;
};

struct pthread_barrierattr {
	int pshared;
};

struct pthread_spinlock {
	struct _spinlock lock;
	pthread_t owner;
};

struct pthread {
	struct __sem donesem;
#if TLS_VARIANT == 1
	int *errno_ptr;
#endif
	pid_t tid;
	unsigned int flags;
	struct _spinlock flags_lock;
	void *retval;
	void *(*fn)(void *);
	void *arg;
	char name[32];
	struct stack *stack;
	LIST_ENTRY(pthread) threads;
	TAILQ_ENTRY(pthread) waiting;
	pthread_cond_t blocking_cond;
	int sched_policy;
	struct pthread_attr attr;
	struct sched_param sched_param;
	struct rthread_storage *local_storage;
	struct rthread_cleanup_fn *cleanup_fns;
	int myerrno;

	/* currently in a cancel point? */
	int cancel_point;

	/* cancel received in a delayed cancel block? */
	int delayed_cancel;
};
#define	THREAD_DONE		0x001
#define	THREAD_DETACHED		0x002
#define	THREAD_CANCELED		0x004
#define	THREAD_CANCEL_ENABLE	0x008
#define	THREAD_CANCEL_DEFERRED	0x010
#define	THREAD_CANCEL_DELAY	0x020
#define	THREAD_DYING		0x040
#define	THREAD_ORIGINAL		0x080	/* original thread from fork */
#define	THREAD_INITIAL_STACK	0x100	/* thread with stack from exec */

#define	IS_CANCELED(thread) \
	(((thread)->flags & (THREAD_CANCELED|THREAD_DYING)) == THREAD_CANCELED)


extern int _threads_ready;
extern size_t _thread_pagesize;
extern LIST_HEAD(listhead, pthread) _thread_list;
extern struct _spinlock _thread_lock;
extern struct pthread_attr _rthread_attr_default;

#define	ROUND_TO_PAGE(size) \
	(((size) + (_thread_pagesize - 1)) & ~(_thread_pagesize - 1))

void	_spinlock(volatile struct _spinlock *);
int	_spinlocktry(volatile struct _spinlock *);
void	_spinunlock(volatile struct _spinlock *);
int	_sem_wait(sem_t, int, const struct timespec *, int *);
int	_sem_post(sem_t);

int	_rthread_init(void);
void	_rthread_setflag(pthread_t, int);
void	_rthread_clearflag(pthread_t, int);
struct stack *_rthread_alloc_stack(pthread_t);
void	_rthread_free_stack(struct stack *);
void	_rthread_tls_destructors(pthread_t);
void	_rthread_debug(int, const char *, ...)
		__attribute__((__format__ (printf, 2, 3)));
void	_rthread_debug_init(void);
#if defined(__ELF__)
void	_rthread_dl_lock(int what);
void	_rthread_bind_lock(int);
#endif

/* rthread_cancel.c */
void	_enter_cancel(pthread_t);
void	_leave_cancel(pthread_t);
void	_enter_delayed_cancel(pthread_t);
void	_leave_delayed_cancel(pthread_t, int);

void	_thread_dump_info(void);

/* syscalls */
int	getthrid(void);
void	__threxit(pid_t *);
int	__thrsleep(const volatile void *, clockid_t, const struct timespec *,
	    volatile void *, const int *);
int	__thrwakeup(const volatile void *, int n);
int	__thrsigdivert(sigset_t, siginfo_t *, const struct timespec *);
int	sched_yield(void);
int	_thread_sys_sigaction(int, const struct sigaction *,
	    struct sigaction *);
int	_thread_sys_sigprocmask(int, const sigset_t *, sigset_t *);