newlib-cygwin/newlib/libc/stdio/findfp.c

171 lines
3.9 KiB
C

/* No user fns here. Pesch 15apr92. */
/*
* Copyright (c) 1990 The Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms are permitted
* provided that the above copyright notice and this paragraph are
* duplicated in all such forms and that any documentation,
* advertising materials, and other materials related to such
* distribution and use acknowledge that the software was developed
* by the University of California, Berkeley. The name of the
* University may not be used to endorse or promote products derived
* from this software without specific prior written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>
#include <fcntl.h>
#include "local.h"
static void
std (ptr, flags, file, data)
FILE *ptr;
int flags;
int file;
struct _reent *data;
{
ptr->_p = 0;
ptr->_r = 0;
ptr->_w = 0;
ptr->_flags = flags;
ptr->_file = file;
ptr->_bf._base = 0;
ptr->_bf._size = 0;
ptr->_lbfsize = 0;
ptr->_cookie = ptr;
ptr->_read = __sread;
ptr->_write = __swrite;
ptr->_seek = __sseek;
ptr->_close = __sclose;
ptr->_data = data;
#ifdef __SCLE
if (__stextmode(ptr->_file))
ptr->_flags |= __SCLE;
#endif
}
struct _glue *
__sfmoreglue (d, n)
struct _reent *d;
register int n;
{
struct _glue *g;
FILE *p;
g = (struct _glue *) _malloc_r (d, sizeof (*g) + n * sizeof (FILE));
if (g == NULL)
return NULL;
p = (FILE *) (g + 1);
g->_next = NULL;
g->_niobs = n;
g->_iobs = p;
memset (p, 0, n * sizeof (FILE));
return g;
}
/*
* Find a free FILE for fopen et al.
*/
FILE *
__sfp (d)
struct _reent *d;
{
FILE *fp;
int n;
struct _glue *g;
if (!d->__sdidinit)
__sinit (d);
for (g = &d->__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 = __sfmoreglue (d, NDYNAMIC)) == NULL)
break;
}
d->_errno = ENOMEM;
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;
fp->_data = d;
return fp;
}
/*
* 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_r (ptr)
struct _reent *ptr;
{
/* (void) _fwalk(fclose); */
(void) _fwalk (ptr, fflush); /* `cheating' */
}
#ifndef _REENT_ONLY
void
_cleanup ()
{
_cleanup_r (_REENT);
}
#endif
/*
* __sinit() is called whenever stdio's internal variables must be set up.
*/
void
__sinit (s)
struct _reent *s;
{
/* make sure we clean up on exit */
s->__cleanup = _cleanup_r; /* conservative */
s->__sdidinit = 1;
std (s->__sf + 0, __SRD, 0, s);
/* on platforms that have true file system I/O, we can verify whether stdout
is an interactive terminal or not. For all other platforms, we will
default to line buffered mode here. */
#ifdef HAVE_FCNTL
std (s->__sf + 1, __SWR, 1, s);
#else
std (s->__sf + 1, __SWR | __SLBF, 1, s);
#endif
std (s->__sf + 2, __SWR | __SNBF, 2, s);
s->__sglue._next = NULL;
s->__sglue._niobs = 3;
s->__sglue._iobs = &s->__sf[0];
}