newlib/newlib/libc/stdio/findfp.c

367 lines
8.5 KiB
C

/*
* 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,
* and/or 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.
*/
/* No user fns here. Pesch 15apr92. */
#include <_ansi.h>
#include <reent.h>
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>
#include <fcntl.h>
#include <sys/lock.h>
#include "local.h"
#if defined(_REENT_SMALL) && !defined(_REENT_GLOBAL_STDIO_STREAMS)
const struct __sFILE_fake __sf_fake_stdin =
{_NULL, 0, 0, 0, 0, {_NULL, 0}, 0, _NULL};
const struct __sFILE_fake __sf_fake_stdout =
{_NULL, 0, 0, 0, 0, {_NULL, 0}, 0, _NULL};
const struct __sFILE_fake __sf_fake_stderr =
{_NULL, 0, 0, 0, 0, {_NULL, 0}, 0, _NULL};
#endif
#ifdef _REENT_GLOBAL_STDIO_STREAMS
__FILE __sf[3];
#endif
#if (defined (__OPTIMIZE_SIZE__) || defined (PREFER_SIZE_OVER_SPEED))
_NOINLINE_STATIC void
#else
static void
#endif
std (FILE *ptr,
int flags,
int file)
{
ptr->_p = 0;
ptr->_r = 0;
ptr->_w = 0;
ptr->_flags = flags;
ptr->_flags2 = 0;
ptr->_file = file;
ptr->_bf._base = 0;
ptr->_bf._size = 0;
ptr->_lbfsize = 0;
memset (&ptr->_mbstate, 0, sizeof (_mbstate_t));
ptr->_cookie = ptr;
ptr->_read = __sread;
#ifndef __LARGE64_FILES
ptr->_write = __swrite;
#else /* __LARGE64_FILES */
ptr->_write = __swrite64;
ptr->_seek64 = __sseek64;
ptr->_flags |= __SL64;
#endif /* __LARGE64_FILES */
ptr->_seek = __sseek;
#ifdef _STDIO_CLOSE_PER_REENT_STD_STREAMS
ptr->_close = __sclose;
#else /* _STDIO_CLOSE_STD_STREAMS */
ptr->_close = NULL;
#endif /* _STDIO_CLOSE_STD_STREAMS */
#if !defined(__SINGLE_THREAD__) && !(defined(_REENT_SMALL) && !defined(_REENT_GLOBAL_STDIO_STREAMS))
__lock_init_recursive (ptr->_lock);
/*
* #else
* lock is already initialized in __sfp
*/
#endif
#ifdef __SCLE
if (__stextmode (ptr->_file))
ptr->_flags |= __SCLE;
#endif
}
static inline void
stdin_init(FILE *ptr)
{
std (ptr, __SRD, 0);
}
static inline void
stdout_init(FILE *ptr)
{
/* On platforms that have true file system I/O, we can verify
whether stdout is an interactive terminal or not, as part of
__smakebuf on first use of the stream. For all other platforms,
we will default to line buffered mode here. Technically, POSIX
requires both stdin and stdout to be line-buffered, but tradition
leaves stdin alone on systems without fcntl. */
#ifdef HAVE_FCNTL
std (ptr, __SWR, 1);
#else
std (ptr, __SWR | __SLBF, 1);
#endif
}
static inline void
stderr_init(FILE *ptr)
{
/* POSIX requires stderr to be opened for reading and writing, even
when the underlying fd 2 is write-only. */
std (ptr, __SRW | __SNBF, 2);
}
struct glue_with_file {
struct _glue glue;
FILE file;
};
struct _glue *
__sfmoreglue (struct _reent *d,
register int n)
{
struct glue_with_file *g;
g = (struct glue_with_file *)
_malloc_r (d, sizeof (*g) + (n - 1) * sizeof (FILE));
if (g == NULL)
return NULL;
g->glue._next = NULL;
g->glue._niobs = n;
g->glue._iobs = &g->file;
memset (&g->file, 0, n * sizeof (FILE));
return &g->glue;
}
/*
* Find a free FILE for fopen et al.
*/
FILE *
__sfp (struct _reent *d)
{
FILE *fp;
int n;
struct _glue *g;
_newlib_sfp_lock_start ();
if (!_GLOBAL_REENT->__sdidinit)
__sinit (_GLOBAL_REENT);
for (g = &_GLOBAL_REENT->__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;
}
_newlib_sfp_lock_exit ();
d->_errno = ENOMEM;
return NULL;
found:
fp->_file = -1; /* no file */
fp->_flags = 1; /* reserve this slot; caller sets real flags */
fp->_flags2 = 0;
#ifndef __SINGLE_THREAD__
__lock_init_recursive (fp->_lock);
#endif
_newlib_sfp_lock_end ();
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 */
memset (&fp->_mbstate, 0, sizeof (_mbstate_t));
/* 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;
}
/*
* 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 (struct _reent *ptr)
{
int (*cleanup_func) (struct _reent *, FILE *);
#ifdef _STDIO_BSD_SEMANTICS
/* BSD and Glibc systems only flush streams which have been written to
at exit time. Calling flush rather than close for speed, as on
the aforementioned systems. */
cleanup_func = __sflushw_r;
#else
/* Otherwise close files and flush read streams, too.
Note we call flush directly if "--enable-lite-exit" is in effect. */
#ifdef _LITE_EXIT
cleanup_func = _fflush_r;
#else
cleanup_func = _fclose_r;
#endif
#endif
#ifdef _REENT_GLOBAL_STDIO_STREAMS
if (ptr->_stdin != &__sf[0])
(*cleanup_func) (ptr, ptr->_stdin);
if (ptr->_stdout != &__sf[1])
(*cleanup_func) (ptr, ptr->_stdout);
if (ptr->_stderr != &__sf[2])
(*cleanup_func) (ptr, ptr->_stderr);
#endif
(void) _fwalk_reent (ptr, cleanup_func);
}
#ifndef _REENT_ONLY
void
_cleanup (void)
{
_cleanup_r (_GLOBAL_REENT);
}
#endif
/*
* __sinit() is called whenever stdio's internal variables must be set up.
*/
void
__sinit (struct _reent *s)
{
__sinit_lock_acquire ();
if (s->__sdidinit)
{
__sinit_lock_release ();
return;
}
/* make sure we clean up on exit */
s->__cleanup = _cleanup_r; /* conservative */
s->__sglue._next = NULL;
#ifndef _REENT_SMALL
# ifndef _REENT_GLOBAL_STDIO_STREAMS
s->__sglue._niobs = 3;
s->__sglue._iobs = &s->__sf[0];
# endif /* _REENT_GLOBAL_STDIO_STREAMS */
#else
s->__sglue._niobs = 0;
s->__sglue._iobs = NULL;
/* Avoid infinite recursion when calling __sfp for _GLOBAL_REENT. The
problem is that __sfp checks for _GLOBAL_REENT->__sdidinit and calls
__sinit if it's 0. */
if (s == _GLOBAL_REENT)
s->__sdidinit = 1;
# ifndef _REENT_GLOBAL_STDIO_STREAMS
s->_stdin = __sfp(s);
s->_stdout = __sfp(s);
s->_stderr = __sfp(s);
# else /* _REENT_GLOBAL_STDIO_STREAMS */
s->_stdin = &__sf[0];
s->_stdout = &__sf[1];
s->_stderr = &__sf[2];
# endif /* _REENT_GLOBAL_STDIO_STREAMS */
#endif
#ifdef _REENT_GLOBAL_STDIO_STREAMS
if (__sf[0]._cookie == NULL) {
_GLOBAL_REENT->__sglue._niobs = 3;
_GLOBAL_REENT->__sglue._iobs = &__sf[0];
stdin_init (&__sf[0]);
stdout_init (&__sf[1]);
stderr_init (&__sf[2]);
}
#else /* _REENT_GLOBAL_STDIO_STREAMS */
stdin_init (s->_stdin);
stdout_init (s->_stdout);
stderr_init (s->_stderr);
#endif /* _REENT_GLOBAL_STDIO_STREAMS */
s->__sdidinit = 1;
__sinit_lock_release ();
}
#ifndef __SINGLE_THREAD__
__LOCK_INIT_RECURSIVE(static, __sfp_recursive_mutex);
__LOCK_INIT_RECURSIVE(static, __sinit_recursive_mutex);
void
__sfp_lock_acquire (void)
{
__lock_acquire_recursive (__sfp_recursive_mutex);
}
void
__sfp_lock_release (void)
{
__lock_release_recursive (__sfp_recursive_mutex);
}
void
__sinit_lock_acquire (void)
{
__lock_acquire_recursive (__sinit_recursive_mutex);
}
void
__sinit_lock_release (void)
{
__lock_release_recursive (__sinit_recursive_mutex);
}
/* Walkable file locking routine. */
static int
__fp_lock (FILE * ptr)
{
if (!(ptr->_flags2 & __SNLK))
_flockfile (ptr);
return 0;
}
/* Walkable file unlocking routine. */
static int
__fp_unlock (FILE * ptr)
{
if (!(ptr->_flags2 & __SNLK))
_funlockfile (ptr);
return 0;
}
void
__fp_lock_all (void)
{
__sfp_lock_acquire ();
(void) _fwalk (_REENT, __fp_lock);
}
void
__fp_unlock_all (void)
{
(void) _fwalk (_REENT, __fp_unlock);
__sfp_lock_release ();
}
#endif