text: /*
   * Copyright (c) 2005 David Xu <davidxu@freebsd.org>
   * All rights reserved.
   *
   * 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 unmodified, 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.
   *
   * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
   *
   * $FreeBSD: soc2013/dpl/head/lib/librt/aio.c 157121 2006-03-24 03:24:27Z davidxu $
   *
   */
  
  #include <sys/cdefs.h>
  #include <sys/types.h>
  #include <sys/syscall.h>
  #include <sys/aio.h>
  
  #include "namespace.h"
  #include <errno.h>
  #include <stddef.h>
  #include <signal.h>
  #include "sigev_thread.h"
  #include "un-namespace.h"
  
  __weak_reference(__aio_read, _aio_read);
  __weak_reference(__aio_read, aio_read);
  __weak_reference(__aio_write, _aio_write);
  __weak_reference(__aio_write, aio_write);
  __weak_reference(__aio_return, _aio_return);
  __weak_reference(__aio_return, aio_return);
  __weak_reference(__aio_waitcomplete, _aio_waitcomplete);
  __weak_reference(__aio_waitcomplete, aio_waitcomplete);
  __weak_reference(__aio_fsync, _aio_fsync);
  __weak_reference(__aio_fsync, aio_fsync);
  
  typedef void (*aio_func)(union sigval val, struct aiocb *iocb);
  
  extern int __sys_aio_read(struct aiocb *iocb);
  extern int __sys_aio_write(struct aiocb *iocb);
  extern int __sys_aio_waitcomplete(struct aiocb **iocbp, struct timespec *timeout);
  extern int __sys_aio_return(struct aiocb *iocb);
  extern int __sys_aio_error(struct aiocb *iocb);
  extern int __sys_aio_fsync(int op, struct aiocb *iocb);
  
  static void
  aio_dispatch(struct sigev_node *sn)
  {
  	aio_func f = sn->sn_func;
  
  	f(sn->sn_value, (struct aiocb *)sn->sn_id);
  }
  
  static int
  aio_sigev_alloc(struct aiocb *iocb, struct sigev_node **sn,
  	struct sigevent *saved_ev)
  {
  	if (__sigev_check_init()) {
  		/* This might be that thread library is not enabled. */
  		errno = EINVAL;
  		return (-1);
  	}
  
  	*sn = __sigev_alloc(SI_ASYNCIO, &iocb->aio_sigevent, NULL, 1);
  	if (*sn == NULL) {
  		errno = EAGAIN;
  		return (-1);
  	}
  	
  	*saved_ev = iocb->aio_sigevent;
  	(*sn)->sn_id = (sigev_id_t)iocb;
  	__sigev_get_sigevent(*sn, &iocb->aio_sigevent, (*sn)->sn_id);
  	(*sn)->sn_dispatch = aio_dispatch;
  
  	__sigev_list_lock();
  	__sigev_register(*sn);
  	__sigev_list_unlock();
  
  	return (0);
  }
  
  static int
  aio_io(struct aiocb *iocb, int (*sysfunc)(struct aiocb *iocb))
  {
  	struct sigev_node *sn;
  	struct sigevent saved_ev;
  	int ret, err;
  
  	if (iocb->aio_sigevent.sigev_notify != SIGEV_THREAD) {
  		ret = sysfunc(iocb);
  		return (ret);
  	}
  
  	ret = aio_sigev_alloc(iocb, &sn, &saved_ev);
  	if (ret)
  		return (ret);
  	ret = sysfunc(iocb);
  	iocb->aio_sigevent = saved_ev;
  	if (ret != 0) {
  		err = errno;
  		__sigev_list_lock();
  		__sigev_delete_node(sn);
  		__sigev_list_unlock();
  		errno = err;
  	}
  	return (ret);
  }
  
  int
  __aio_read(struct aiocb *iocb)
  {
  
  	return aio_io(iocb, &__sys_aio_read);
  }
  
  int
  __aio_write(struct aiocb *iocb)
  {
  
  	return aio_io(iocb, &__sys_aio_write);
  }
  
  int
  __aio_waitcomplete(struct aiocb **iocbp, struct timespec *timeout)
  {
  	int err;
  	int ret = __sys_aio_waitcomplete(iocbp, timeout);
  
  	if (*iocbp) {
  		if ((*iocbp)->aio_sigevent.sigev_notify == SIGEV_THREAD) {
  			err = errno;
  			__sigev_list_lock();
  			__sigev_delete(SI_ASYNCIO, (sigev_id_t)(*iocbp));
  			__sigev_list_unlock();
  			errno = err;
  		}
  	}
  
  	return (ret);
  }
  
  int
  __aio_return(struct aiocb *iocb)
  {
  
  	if (iocb->aio_sigevent.sigev_notify == SIGEV_THREAD) {
  		if (__sys_aio_error(iocb) == EINPROGRESS)
  			return (EINPROGRESS);
  		__sigev_list_lock();
  		__sigev_delete(SI_ASYNCIO, (sigev_id_t)iocb);
  		__sigev_list_unlock();
  	}
  
  	return __sys_aio_return(iocb);
  }
  
  int
  __aio_fsync(int op, struct aiocb *iocb)
  {
  	struct sigev_node *sn;
  	struct sigevent saved_ev;
  	int ret, err;
  
  	if (iocb->aio_sigevent.sigev_notify != SIGEV_THREAD)
  		return __sys_aio_fsync(op, iocb);
  
  	ret = aio_sigev_alloc(iocb, &sn, &saved_ev);
  	if (ret)
  		return (ret);
  	ret = __sys_aio_fsync(op, iocb);
  	iocb->aio_sigevent = saved_ev;
  	if (ret != 0) {
  		err = errno;
  		__sigev_list_lock();
  		__sigev_delete_node(sn);
  		__sigev_list_unlock();
  		errno = err;
  	}
  	return (ret);
  }
  