/*
 * pthread.h - pthread primitives
 *
 *   Copyright (c) 2000-2020  Shiro Kawai  <shiro@acm.org>
 *
 *   Redistribution and use in source and binary forms, with or without
 *   modification, are permitted provided that the following conditions
 *   are met:
 *
 *   1. Redistributions of source code must retain the above copyright
 *      notice, this list of conditions and the following disclaimer.
 *
 *   2. Redistributions in binary form must reproduce the above copyright
 *      notice, this list of conditions and the following disclaimer in the
 *      documentation and/or other materials provided with the distribution.
 *
 *   3. Neither the name of the authors nor the names of its contributors
 *      may be used to endorse or promote products derived from this
 *      software without specific prior written permission.
 *
 *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
 *   TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 *   PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 *   LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 *   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 *   SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#ifndef GAUCHE_PTHREAD_H
#define GAUCHE_PTHREAD_H

/* Abstract thread implementation based on pthreads.
 * See gauche/uthread.h for the detailed semantics of those macros.
 */

#include <pthread.h>

#define GAUCHE_HAS_THREADS 1

/* Thread */
typedef pthread_t ScmInternalThread;
#define SCM_INTERNAL_THREAD_INIT(thr)   ((thr) = (pthread_t)NULL)
#define SCM_INTERNAL_THREAD_INITIALIZED_P(thr)  ((thr) != (pthread_t)NULL)
#define SCM_INTERNAL_THREAD_GETCURRENT()  pthread_self()
#define SCM_INTERNAL_THREAD_SETSPECIFIC(key, val) \
    (pthread_setspecific((key), (val)) == 0)
#define SCM_INTERNAL_THREAD_EXIT()        pthread_exit(NULL)

#define SCM_INTERNAL_THREAD_CLEANUP_PUSH(fn, data) \
    pthread_cleanup_push(fn, data)
#define SCM_INTERNAL_THREAD_CLEANUP_POP() \
    pthread_cleanup_pop(1)

#define SCM_INTERNAL_THREAD_PROC_RETTYPE   void*
#define SCM_INTERNAL_THREAD_PROC_RETVAL    NULL

/* On POSIX systems, when available, we reserve one signal to notify
   other threads to terminate.
   NB: POSIX requires at least 8 realtime signals, but cygwin doesn't
   provide them (on cygwin, SIGRTMIN == SIGRTMAX).   We use SIGPWR
   instead.
*/
#if defined(SIGRTMIN) && !defined(GAUCHE_PTHREAD_SIGNAL)
#  if !defined(__CYGWIN__)
#    define GAUCHE_PTHREAD_SIGNAL (SIGRTMIN+5)
#  else
#    define GAUCHE_PTHREAD_SIGNAL SIGPWR
#  endif
#endif /*defined(SIGRTMIN) && !defined(GAUCHE_PTHREAD_SIGNAL)*/

/* Mutex */
typedef pthread_mutex_t ScmInternalMutex;
#define SCM_INTERNAL_MUTEX_INIT(mutex)    pthread_mutex_init(&(mutex), NULL)
#define SCM_INTERNAL_MUTEX_LOCK(mutex)    pthread_mutex_lock(&(mutex))
#define SCM_INTERNAL_MUTEX_UNLOCK(mutex)  pthread_mutex_unlock(&(mutex))
#define SCM_INTERNAL_MUTEX_DESTROY(mutex) pthread_mutex_destroy(&(mutex))
#define SCM_INTERNAL_MUTEX_INITIALIZER    PTHREAD_MUTEX_INITIALIZER

SCM_EXTERN void Scm__MutexCleanup(void *); /* in core.c */

/* Mutex operation with cleanup.  The dummy statement before
   pthread_cleanup_pop() allows a label to be placed before
   SAFE_LOCK_END macro.  Without that, it could be an error
   if pthread_cleanup_pop expands into something beginning with
   closing brace. */
#define SCM_INTERNAL_MUTEX_SAFE_LOCK_BEGIN(mutex)               \
    pthread_mutex_lock(&(mutex));                               \
    pthread_cleanup_push(Scm__MutexCleanup, &(mutex))
#define SCM_INTERNAL_MUTEX_SAFE_LOCK_END() /*dummy*/; pthread_cleanup_pop(1)

/* Condition variable */
typedef pthread_cond_t ScmInternalCond;
#define SCM_INTERNAL_COND_INIT(cond)        pthread_cond_init(&(cond), NULL)
#define SCM_INTERNAL_COND_SIGNAL(cond)      pthread_cond_signal(&(cond))
#define SCM_INTERNAL_COND_BROADCAST(cond)   pthread_cond_broadcast(&(cond))
#define SCM_INTERNAL_COND_WAIT(cond, mutex) pthread_cond_wait(&(cond), &(mutex))
#define SCM_INTERNAL_COND_TIMEDWAIT(cond, mutex, ptimespec) \
    pthread_cond_timedwait(&(cond), &(mutex), (ptimespec))
#define SCM_INTERNAL_COND_DESTROY(cond)     pthread_cond_destroy(&(cond))
#define SCM_INTERNAL_COND_INITIALIZER       PTHREAD_COND_INITIALIZER
#define SCM_INTERNAL_COND_TIMEDOUT          ETIMEDOUT
#define SCM_INTERNAL_COND_INTR              EINTR

/* Fast lock */
#ifdef HAVE_PTHREAD_SPINLOCK_T
typedef pthread_spinlock_t ScmInternalFastlock;
#define SCM_INTERNAL_FASTLOCK_INIT(spin) \
    pthread_spin_init(&(spin), PTHREAD_PROCESS_PRIVATE)
#define SCM_INTERNAL_FASTLOCK_LOCK(spin) \
    pthread_spin_lock(&(spin))
#define SCM_INTERNAL_FASTLOCK_UNLOCK(spin) \
    pthread_spin_unlock(&(spin))
#define SCM_INTERNAL_FASTLOCK_DESTROY(spin) \
    pthread_spin_destroy(&(spin))
#else  /*!HAVE_PTHREAD_SPINLOCK_T*/
typedef pthread_mutex_t ScmInternalFastlock;
#define SCM_INTERNAL_FASTLOCK_INIT(fl)   SCM_INTERNAL_MUTEX_INIT(fl)
#define SCM_INTERNAL_FASTLOCK_LOCK(fl)   SCM_INTERNAL_MUTEX_LOCK(fl)
#define SCM_INTERNAL_FASTLOCK_UNLOCK(fl) SCM_INTERNAL_MUTEX_UNLOCK(fl)
#define SCM_INTERNAL_FASTLOCK_DESTROY(fl) SCM_INTERNAL_MUTEX_DESTROY(fl)
#endif /*!HAVE_PTHREAD_SPINLOCK_T*/

/* Issues a full memory barrier */
#define SCM_INTERNAL_SYNC()                 __sync_synchronize()

#endif /* GAUCHE_PTHREAD_H */
