/*-
 * Copyright (c) 2002-2018 The UbixOS Project.
 * All rights reserved.
 *
 * This was developed by Christopher W. Olsen for the UbixOS Project.
 *
 * 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, the following disclaimer and the list of authors.
 * 2) Redistributions in binary form must reproduce the above copyright notice, this list of
 *    conditions, the following disclaimer and the list of authors in the documentation and/or
 *    other materials provided with the distribution.
 * 3) Neither the name of the UbixOS Project 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 AUTHOR 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 _SYS_SELECT_H
#define _SYS_SELECT_H

#include <sys/cdefs.h>
#include <sys/_types.h>
#include <sys/_timespec.h>
#include <sys/_timeval.h>

#include <sys/_sigset.h>

typedef unsigned long __fd_mask;
typedef __fd_mask fd_mask;

#ifndef _SIGSET_T_DECLARED
#define _SIGSET_T_DECLARED
typedef __sigset_t sigset_t;
#endif

/*
 * Select uses bit masks of file descriptors in longs.  These macros
 * manipulate such bit fields (the filesystem macros use chars).
 * FD_SETSIZE may be defined by the user, but the default here should
 * be enough for most uses.
 */
#ifndef FD_SETSIZE
#define FD_SETSIZE      1024
#endif

#define _NFDBITS        (sizeof(__fd_mask) * 8) /* bits per mask */
#define NFDBITS         _NFDBITS

#ifndef _howmany
#define _howmany(x, y)  (((x) + ((y) - 1)) / (y))
#endif

typedef struct fd_set {
    __fd_mask        __fds_bits [_howmany(FD_SETSIZE, _NFDBITS)];
} fd_set;

#define fds_bits        __fds_bits

#define __fdset_mask(n) ((__fd_mask)1 << ((n) % _NFDBITS))
#define FD_CLR(n, p)    ((p)->__fds_bits[(n)/_NFDBITS] &= ~__fdset_mask(n))
#define FD_COPY(f, t)   (void)(*(t) = *(f))
#define FD_ISSET(n, p)  (((p)->__fds_bits[(n)/_NFDBITS] & __fdset_mask(n)) != 0)
#define FD_SET(n, p)    ((p)->__fds_bits[(n)/_NFDBITS] |= __fdset_mask(n))
#define FD_ZERO(p) do {                                 \
        fd_set *_p;                                     \
        __size_t _n;                                    \
                                                        \
        _p = (p);                                       \
        _n = _howmany(FD_SETSIZE, _NFDBITS);            \
        while (_n > 0)                                  \
                _p->__fds_bits[--_n] = 0;               \
} while (0)

#ifndef _KERNEL

__BEGIN_DECLS
int pselect(int, fd_set *__restrict, fd_set *__restrict, fd_set *__restrict, const struct timespec *__restrict, const sigset_t *__restrict);

#ifndef _SELECT_DECLARED
#define _SELECT_DECLARED
/* XXX missing restrict type-qualifier */
int select(int, fd_set *, fd_set *, fd_set *, struct timeval *);
#endif
__END_DECLS
#endif /* !_KERNEL */



#endif /* END _SYS_SELECT_H */