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/*-

 * Copyright (c) 1990, 1993

 *      The Regents of the University of California.  All rights reserved.

 *

 * This code is derived from software contributed to Berkeley by

 * Chris Torek.

 *

 * 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. All advertising materials mentioning features or use of this software

 *    must display the following acknowledgement:

 *      This product includes software developed by the University of

 *      California, Berkeley and its contributors.

 * 4. 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.

 */

/* MODIFIED:

 * -- added _THREAD_SAFE an all similar stuff

 * -- modified initialization and termination

 */

#if defined(LIBC_SCCS) && !defined(lint)

#if 0

static char sccsid[] = "@(#)findfp.c    8.2 (Berkeley) 1/4/94";

#endif

static const char rcsid[] =

                "$\Id: findfp.c,v 1.3 1996/06/22 10:33:12 jraynard Exp $";

#endif /* LIBC_SCCS and not lint */

#ifdef _THREAD_SAFE

#include <kernel/func.h>

#include <kernel/model.h>

static NOPM_mutexattr_t mutexattr=NOPM_MUTEXATTR_INITIALIZER;

#endif

#include <sys/param.h>

#include <unistd.h>

#include <stdio.h>

#include <errno.h>

#include <stdlib.h>

#include <string.h>

#include "local.h"

#include "glue.h"

/* MG (added =0) */

int     __sdidinit=0;

#define NDYNAMIC 10             /* add ten more whenever necessary */

#define std(flags, file) \

        {0,0,0,flags,file,{0},0,__sF+file,__sclose,__sread,__sseek,__swrite}

/*       p r w flags file _bf z  cookie      close    read    seek    write */

                                /* the usual - (stdin + stdout + stderr) */

static FILE usual[FOPEN_MAX - 3];

static struct glue uglue = { 0, FOPEN_MAX - 3, usual };

FILE __sF[3] = {

        std(__SRD|__SLBF, STDIN_FILENO),        /* stdin */

        std(__SWR|__SLBF, STDOUT_FILENO),       /* stdout */

        std(__SWR|__SNBF, STDERR_FILENO)        /* stderr */

};

struct glue __sglue = { &uglue, 3, __sF };

static struct glue *    moreglue __P((int));

static struct glue *

moreglue(n)

        register int n;

{

        register struct glue *g;

        register FILE *p;

        static FILE empty;

        g = (struct glue *)malloc(sizeof(*g) + ALIGNBYTES + n * sizeof(FILE));

        if (g == NULL)

                return (NULL);

        p = (FILE *)ALIGN(g + 1);

        g->next = NULL;

        g->niobs = n;

        g->iobs = p;

        while (--n >= 0) {

                *p = empty;

#ifdef _THREAD_SAFE

                mutex_init(&p->_mutex,&mutexattr);             

#endif

                p++;

        }

        return (g);

}

/*

 * Find a free FILE for fopen et al.

 */

FILE *

__sfp()

{

        register FILE *fp;

        register int n;

        register struct glue *g;

        if (!__sdidinit)

                __sinit();

        for (g = &__sglue;; g = g->next) {

                for (fp = g->iobs, n = g->niobs; --n >= 0; fp++)

                        if (fp->_flags == 0)

                                goto found;

                if (g->next == NULL && (g->next = moreglue(NDYNAMIC)) == NULL)

                        break;

        }

        return (NULL);

found:

        fp->_flags = 1;         /* reserve this slot; caller sets real flags */

        fp->_p = NULL;          /* no current pointer */

        fp->_w = 0;             /* nothing to read or write */

        fp->_r = 0;

        fp->_bf._base = NULL;   /* no buffer */

        fp->_bf._size = 0;

        fp->_lbfsize = 0;       /* not line buffered */

        fp->_file = -1;         /* no file */

/*      fp->_cookie = <any>; */ /* caller sets cookie, _read/_write etc */

        fp->_ub._base = NULL;   /* no ungetc buffer */

        fp->_ub._size = 0;

        fp->_lb._base = NULL;   /* no line buffer */

        fp->_lb._size = 0;

        return (fp);

}

/*

 * XXX.  Force immediate allocation of internal memory.  Not used by stdio,

 * but documented historically for certain applications.  Bad applications.

 */

__warn_references(f_prealloc,

        "warning: this program uses f_prealloc(), which is stupid.");

void

f_prealloc()

{

        register struct glue *g;

        int n;

        n = getdtablesize() - FOPEN_MAX + 20;           /* 20 for slop. */

        for (g = &__sglue; (n -= g->niobs) > 0 && g->next; g = g->next)

                /* void */;

        if (n > 0)

                g->next = moreglue(n);

}

/*

 * exit() calls _cleanup() through *__cleanup, set whenever we

 * open or buffer a file.  This chicanery is done so that programs

 * that do not use stdio need not link it all in.

 *

 * The name `_cleanup' is, alas, fairly well known outside stdio.

 */

void

_cleanup()

{

        /* (void) _fwalk(fclose); */

        (void) _fwalk(__sflush);                /* `cheating' */

}

/*

 * __sinit() is called whenever stdio's internal variables must be set up.

 */

void

__sinit()

{

#ifdef _THREAD_SAFE

  register FILE *fp;

  register int n;

  register struct glue *g;

#endif

  /* make sure we clean up on exit */

  __cleanup = _cleanup;         /* conservative */

  __sdidinit = 1;

#ifdef _THREAD_SAFE

  for (g = &__sglue;; g = g->next) {

    for (fp = g->iobs, n = g->niobs; --n >= 0; fp++)

      mutex_init(&fp->_mutex,&mutexattr);

    if (g->next == NULL) break;

  }

#endif

}