/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright (c) 1992, 1993
 *      The Regents of the University of California.  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, 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 University 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 REGENTS 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 REGENTS 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/_sigset.h>
#include <sys/_timeval.h>
#include <sys/timespec.h>

typedef unsigned long   __fd_mask;
#if __BSD_VISIBLE
typedef __fd_mask       fd_mask;
#endif

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

#if !defined(_KERNEL) && defined(_FORTIFY_SOURCE) && _FORTIFY_SOURCE > 0
#include <ssp/ssp.h>
#else
#define __SSP_FORTIFY_LEVEL     0
#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 */
#if __BSD_VISIBLE
#define NFDBITS         _NFDBITS
#endif

#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;
#if __BSD_VISIBLE
#define fds_bits        __fds_bits
#endif

#define __fdset_idx_(p, n)      ((n) / _NFDBITS)
#if __SSP_FORTIFY_LEVEL == 0
#define __fdset_idx(p, n)       __fdset_idx_(p, n)
#else
__ssp_inline unsigned long
__fdset_idx(const fd_set *p, unsigned long idx)
{
        __size_t psz = __ssp_bos0(p);
        unsigned long sidx = __fdset_idx_(p, idx);

        if (idx >= FD_SETSIZE)
                __chk_fail();
        if (psz / sizeof(__fd_mask) < (sidx + 1))
                __chk_fail();

        return (sidx);
}
#endif

#define __fdset_mask(n) ((__fd_mask)1 << ((n) % _NFDBITS))
#define FD_CLR(n, p)    ((p)->__fds_bits[__fdset_idx(p, n)] &= ~__fdset_mask(n))
#if __BSD_VISIBLE
#define FD_COPY(f, t)   (void)(*(t) = *(f))
#endif
#define FD_ISSET(n, p)  \
    (((p)->__fds_bits[__fdset_idx(p, n)] & __fdset_mask(n)) != 0)
#define FD_SET(n, p)    ((p)->__fds_bits[__fdset_idx(p, n)] |= __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 /* _SYS_SELECT_H_ */