/* $Xorg: Berklib.c,v 1.4 2001/02/09 02:03:48 xorgcvs Exp $ */
/*

Copyright 1987, 1998 The Open Group

Permission to use, copy, modify, distribute, and sell this software and its
documentation for any purpose is hereby granted without fee, provided that
the above copyright notice appear in all copies and that both that
copyright notice and this permission notice appear in supporting
documentation.

The above copyright notice and this permission notice shall be included
in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
IN NO EVENT SHALL THE OPEN GROUP BE LIABLE FOR ANY CLAIM, DAMAGES OR
OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
OTHER DEALINGS IN THE SOFTWARE.

Except as contained in this notice, the name of The Open Group shall
not be used in advertising or otherwise to promote the sale, use or
other dealings in this Software without prior written authorization
from The Open Group.

*/
/* $XFree86: xc/lib/Xbsd/Berklib.c,v 3.9 2001/12/14 19:54:54 dawes Exp $ */


/*
 * These are routines found in BSD but not on all other systems.  The core
 * MIT distribution does not use them except for ffs in the server, unless
 * the system is seriously deficient.  You should enable only the ones that
 * you need for your system.  Use Xfuncs.h in clients to avoid using the
 * slow versions of bcopy, bcmp, and bzero provided here.
 */

#include <sys/types.h>

#ifdef hpux
#define WANT_RANDOM
#define WANT_QUE
#endif

#ifdef macII
/* silly bcopy in A/UX does not handle overlaps */
#define WANT_BFUNCS
#define WANT_MEMMOVE
#define NO_BZERO
#define WANT_RANDOM
#endif

#if defined(SVR4) && !defined(SCO325)
#define WANT_BFUNCS
#define WANT_FFS
#define WANT_RANDOM
#endif

#ifdef hcx
#define WANT_FFS
#endif

#ifdef SYSV
#ifdef i386
#ifndef SCO
#define WANT_FFS
#define WANT_MEMMOVE
#endif
#endif
#endif

#ifdef _SEQUENT_
#define WANT_GTOD
#define WANT_FFS
#endif /* _SEQUENT_ */

/* you should use Xfuncs.h in code instead of relying on Berklib */
#ifdef WANT_BFUNCS

#include <X11/Xosdefs.h>

#if (__STDC__) || defined(SVR4) || defined(hpux)

#include <string.h>

void bcopy (b1, b2, length)
    register char *b1, *b2;
    register int length;
{
    memmove(b2, b1, (size_t)length);
}

int bcmp (b1, b2, length)
    register char *b1, *b2;
    register int length;
{
    return memcmp(b1, b2, (size_t)length);
}

void bzero (b, length)
    register char *b;
    register int length;
{
    memset(b, 0, (size_t)length);
}

#else

void bcopy (b1, b2, length)
    register char *b1, *b2;
    register int length;
{
    if (b1 < b2) {
	b2 += length;
	b1 += length;
	while (length--)
	    *--b2 = *--b1;
    } else {
	while (length--)
	    *b2++ = *b1++;
    }
}

#if defined(SYSV)

#include <memory.h>

int bcmp (b1, b2, length)
    register char *b1, *b2;
    register int length;
{
    return memcmp(b1, b2, length);
}

#ifndef NO_BZERO

bzero (b, length)
    register char *b;
    register int length;
{
    memset(b, 0, length);
}

#endif

#else

int bcmp (b1, b2, length)
    register char *b1, *b2;
    register int length;
{
    while (length--) {
	if (*b1++ != *b2++) return 1;
    }
    return 0;
}

void bzero (b, length)
    register char *b;
    register int length;
{
    while (length--)
	*b++ = '\0';
}

#endif
#endif
#endif /* WANT_BFUNCS */

#ifdef WANT_MEMMOVE
char *memmove (b1, b2, length)
    register char *b1, *b2;
    register int length;
{
    char *sb1 = b1;

    if (b2 < b1) {
	b1 += length;
	b2 += length;
	while (length--)
	    *--b1 = *--b2;
    } else {
	while (length--)
	    *b1++ = *b2++;
    }
    return sb1;
}
#endif

#ifdef WANT_FFS
int
ffs(mask)
unsigned int	mask;
{
    register i;

    if ( ! mask ) return 0;
    i = 1;
    while (! (mask & 1)) {
	i++;
	mask = mask >> 1;
    }
    return i;
}
#endif

#ifdef WANT_RANDOM
#if defined(SYSV) || defined(SVR4) || defined(hpux)

long lrand48();

long random()
{
   return (lrand48());
}

void srandom(seed)
    int seed;
{
   srand48(seed);
}

#else

long random()
{
   return (rand());
}

void srandom(seed)
    int seed;
{
   srand(seed);
}

#endif
#endif /* WANT_RANDOM */

/*
 * insque, remque - insert/remove element from a queue
 *
 * DESCRIPTION
 *      Insque and remque manipulate queues built from doubly linked
 *      lists.  Each element in the queue must in the form of
 *      ``struct qelem''.  Insque inserts elem in a queue immedi-
 *      ately after pred; remque removes an entry elem from a queue.
 *
 * SEE ALSO
 *      ``VAX Architecture Handbook'', pp. 228-235.
 */

#ifdef WANT_QUE
struct qelem {
    struct    qelem *q_forw;
    struct    qelem *q_back;
    char *q_data;
    };

insque(elem, pred)
register struct qelem *elem, *pred;
{
    register struct qelem *q;
    /* Insert locking code here */
    if ( elem->q_forw = q = (pred ? pred->q_forw : pred) )
	q->q_back = elem;
    if ( elem->q_back = pred )
	pred->q_forw = elem;
    /* Insert unlocking code here */
}

remque(elem)
register struct qelem *elem;
{
    register struct qelem *q;
    if ( ! elem ) return;
    /* Insert locking code here */

    if ( q = elem->q_back ) q->q_forw = elem->q_forw;
    if ( q = elem->q_forw ) q->q_back = elem->q_back;

    /* insert unlocking code here */
}
#endif /* WANT_QUE */

/*
 * gettimeofday emulation
 * Caution -- emulation is incomplete
 *  - has only second, not microsecond, resolution.
 *  - does not return timezone info.
 */

#ifdef WANT_GTOD

#ifdef _SEQUENT_
#include <X11/Xos.h>
#endif /* _SEQUENT_ */

int gettimeofday (tvp, tzp)
    struct timeval *tvp;
    struct timezone *tzp;
{
#ifdef _SEQUENT_
    /*
     * Sequent has microsecond resolution. Need to link with -lseq
     */
    get_process_stats (tvp, -1, NULL, NULL);
#ifndef SVR4
    if (tzp)
    {
        tzset ();
        tzp->tz_minuteswest = timezone / 60;
        tzp->tz_dsttime = daylight;
    }
#endif /* SVR4 */
    return (0);
#else /* _SEQUENT_ */
    time (&tvp->tv_sec);
    tvp->tv_usec = 0L;

#ifndef SVR4
    if (tzp) {
	fprintf( stderr,
		 "Warning: gettimeofday() emulation does not return timezone\n"
		);
    }
#endif /* SVR4 */
#endif /* _SEQUENT_ */
}
#endif /* WANT_GTOD */