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freebsd-dev/lib/libc/stdio/fclose.c

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BSD 4.4 Lite Lib Sources
1994-05-27 05:00:24 +00:00
/*-
* 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.
* 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.
*/
#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)fclose.c 8.1 (Berkeley) 6/4/93";
#endif /* LIBC_SCCS and not lint */
Fix the style of the SCM ID's. I believe have made all of libc .c's as consistent as possible.
2002-03-22 21:53:29 +00:00
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
BSD 4.4 Lite Lib Sources
1994-05-27 05:00:24 +00:00
Remove _THREAD_SAFE and make libc thread-safe by default by adding (weak definitions to) stubs for some of the pthread functions. If the threads library is linked in, the real pthread functions will pulled in. Use the following convention for system calls wrapped by the threads library: __sys_foo - actual system call _foo - weak definition to __sys_foo foo - weak definition to __sys_foo Change all libc uses of system calls wrapped by the threads library from foo to _foo. In order to define the prototypes for _foo(), we introduce namespace.h and un-namespace.h (suggested by bde). All files that need to reference these system calls, should include namespace.h before any standard includes, then include un-namespace.h after the standard includes and before any local includes. <db.h> is an exception and shouldn't be included in between namespace.h and un-namespace.h namespace.h will define foo to _foo, and un-namespace.h will undefine foo. Try to eliminate some of the recursive calls to MT-safe functions in libc/stdio in preparation for adding a mutex to FILE. We have recursive mutexes, but would like to avoid using them if possible. Remove uneeded includes of <errno.h> from a few files. Add $FreeBSD$ to a few files in order to pass commitprep. Approved by: -arch
2001-01-24 13:01:12 +00:00
#include "namespace.h"
BSD 4.4 Lite Lib Sources
1994-05-27 05:00:24 +00:00
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
Remove _THREAD_SAFE and make libc thread-safe by default by adding (weak definitions to) stubs for some of the pthread functions. If the threads library is linked in, the real pthread functions will pulled in. Use the following convention for system calls wrapped by the threads library: __sys_foo - actual system call _foo - weak definition to __sys_foo foo - weak definition to __sys_foo Change all libc uses of system calls wrapped by the threads library from foo to _foo. In order to define the prototypes for _foo(), we introduce namespace.h and un-namespace.h (suggested by bde). All files that need to reference these system calls, should include namespace.h before any standard includes, then include un-namespace.h after the standard includes and before any local includes. <db.h> is an exception and shouldn't be included in between namespace.h and un-namespace.h namespace.h will define foo to _foo, and un-namespace.h will undefine foo. Try to eliminate some of the recursive calls to MT-safe functions in libc/stdio in preparation for adding a mutex to FILE. We have recursive mutexes, but would like to avoid using them if possible. Remove uneeded includes of <errno.h> from a few files. Add $FreeBSD$ to a few files in order to pass commitprep. Approved by: -arch
2001-01-24 13:01:12 +00:00
#include "un-namespace.h"
Take the spinlock around clearing of the fp->_flags in fclose(3), which indicates the avaliability of FILE, to prevent possible reordering of the writes as seen by other CPUs. Reported by: Fengwei yin <yfw.bsd gmail com> Reviewed by: jhb MFC after: 1 week
2012-04-24 17:51:36 +00:00
#include <spinlock.h>
Add FILE locking stubs for libc. Change the FILE locking to support kernel threads when linked with libpthread (which you haven't see yet). This requires that libc become thread-safe and thread-aware, testing __isthreaded before attempting to do lock/unlock calls. The impact on non-threaded programs is minor. This change works with libc_r, so it's the best compromise.
1998-04-11 07:40:47 +00:00
#include "libc_private.h"
Remove _THREAD_SAFE and make libc thread-safe by default by adding (weak definitions to) stubs for some of the pthread functions. If the threads library is linked in, the real pthread functions will pulled in. Use the following convention for system calls wrapped by the threads library: __sys_foo - actual system call _foo - weak definition to __sys_foo foo - weak definition to __sys_foo Change all libc uses of system calls wrapped by the threads library from foo to _foo. In order to define the prototypes for _foo(), we introduce namespace.h and un-namespace.h (suggested by bde). All files that need to reference these system calls, should include namespace.h before any standard includes, then include un-namespace.h after the standard includes and before any local includes. <db.h> is an exception and shouldn't be included in between namespace.h and un-namespace.h namespace.h will define foo to _foo, and un-namespace.h will undefine foo. Try to eliminate some of the recursive calls to MT-safe functions in libc/stdio in preparation for adding a mutex to FILE. We have recursive mutexes, but would like to avoid using them if possible. Remove uneeded includes of <errno.h> from a few files. Add $FreeBSD$ to a few files in order to pass commitprep. Approved by: -arch
2001-01-24 13:01:12 +00:00
#include "local.h"
BSD 4.4 Lite Lib Sources
1994-05-27 05:00:24 +00:00
Reviewed by: julian and (hsu?) Submitted by: John Birrel(L?) changes for threadsafe operations
1996-01-22 00:02:33 +00:00
int
libc MT-safety, part 2. Add a lock to FILE. flockfile and friends are now implemented (for the most part) in libc. flockfile_debug is implemented in libc_r; I suppose it's about time to kill it but will do it in a future commit. Fix a potential deadlock in _fwalk in a threaded environment. A file flag (__SIGN) was added to stdio.h that, when set, tells _fwalk to ignore it in its walk. This seemed to be needed in refill.c because each file needs to be locked when flushing. Add a stub for pthread_self in libc. This is needed by flockfile which is allowed by POSIX to be recursive. Make fgetpos() error return value (-1) match man page. Remove recursive calls to locked functions (stdio); I think I've got them all, but I may have missed a couple. A few K&R -> ANSI conversions along with removal of a few instances of "register". $Id$ -> $FreeBSD$ in libc/stdio/rget.c Not objected to: -arch, a few months ago
2001-02-11 22:06:43 +00:00
fclose(FILE *fp)
BSD 4.4 Lite Lib Sources
1994-05-27 05:00:24 +00:00
{
Remove _THREAD_SAFE and make libc thread-safe by default by adding (weak definitions to) stubs for some of the pthread functions. If the threads library is linked in, the real pthread functions will pulled in. Use the following convention for system calls wrapped by the threads library: __sys_foo - actual system call _foo - weak definition to __sys_foo foo - weak definition to __sys_foo Change all libc uses of system calls wrapped by the threads library from foo to _foo. In order to define the prototypes for _foo(), we introduce namespace.h and un-namespace.h (suggested by bde). All files that need to reference these system calls, should include namespace.h before any standard includes, then include un-namespace.h after the standard includes and before any local includes. <db.h> is an exception and shouldn't be included in between namespace.h and un-namespace.h namespace.h will define foo to _foo, and un-namespace.h will undefine foo. Try to eliminate some of the recursive calls to MT-safe functions in libc/stdio in preparation for adding a mutex to FILE. We have recursive mutexes, but would like to avoid using them if possible. Remove uneeded includes of <errno.h> from a few files. Add $FreeBSD$ to a few files in order to pass commitprep. Approved by: -arch
2001-01-24 13:01:12 +00:00
int r;
BSD 4.4 Lite Lib Sources
1994-05-27 05:00:24 +00:00
if (fp->_flags == 0) { /* not open! */
errno = EBADF;
return (EOF);
}
Add FILE locking stubs for libc. Change the FILE locking to support kernel threads when linked with libpthread (which you haven't see yet). This requires that libc become thread-safe and thread-aware, testing __isthreaded before attempting to do lock/unlock calls. The impact on non-threaded programs is minor. This change works with libc_r, so it's the best compromise.
1998-04-11 07:40:47 +00:00
FLOCKFILE(fp);
BSD 4.4 Lite Lib Sources
1994-05-27 05:00:24 +00:00
r = fp->_flags & __SWR ? __sflush(fp) : 0;
if (fp->_close != NULL && (*fp->_close)(fp->_cookie) < 0)
r = EOF;
if (fp->_flags & __SMBF)
free((char *)fp->_bf._base);
if (HASUB(fp))
FREEUB(fp);
if (HASLB(fp))
FREELB(fp);
Reviewed by: julian and (hsu?) Submitted by: John Birrel(L?) changes for threadsafe operations
1996-01-22 00:02:33 +00:00
fp->_file = -1;
BSD 4.4 Lite Lib Sources
1994-05-27 05:00:24 +00:00
fp->_r = fp->_w = 0; /* Mess up if reaccessed. */
Take the spinlock around clearing of the fp->_flags in fclose(3), which indicates the avaliability of FILE, to prevent possible reordering of the writes as seen by other CPUs. Reported by: Fengwei yin <yfw.bsd gmail com> Reviewed by: jhb MFC after: 1 week
2012-04-24 17:51:36 +00:00
/*
* Lock the spinlock used to protect __sglue list walk in
* __sfp(). The __sfp() uses fp->_flags == 0 test as an
* indication of the unused FILE.
*
* Taking the lock prevents possible compiler or processor
* reordering of the writes performed before the final _flags
* cleanup, making sure that we are done with the FILE before
* it is considered available.
*/
STDIO_THREAD_LOCK();
Make __sfp() even more thread-safe.
1999-11-21 22:34:57 +00:00
fp->_flags = 0; /* Release this FILE for reuse. */
Take the spinlock around clearing of the fp->_flags in fclose(3), which indicates the avaliability of FILE, to prevent possible reordering of the writes as seen by other CPUs. Reported by: Fengwei yin <yfw.bsd gmail com> Reviewed by: jhb MFC after: 1 week
2012-04-24 17:51:36 +00:00
STDIO_THREAD_UNLOCK();
libc MT-safety, part 2. Add a lock to FILE. flockfile and friends are now implemented (for the most part) in libc. flockfile_debug is implemented in libc_r; I suppose it's about time to kill it but will do it in a future commit. Fix a potential deadlock in _fwalk in a threaded environment. A file flag (__SIGN) was added to stdio.h that, when set, tells _fwalk to ignore it in its walk. This seemed to be needed in refill.c because each file needs to be locked when flushing. Add a stub for pthread_self in libc. This is needed by flockfile which is allowed by POSIX to be recursive. Make fgetpos() error return value (-1) match man page. Remove recursive calls to locked functions (stdio); I think I've got them all, but I may have missed a couple. A few K&R -> ANSI conversions along with removal of a few instances of "register". $Id$ -> $FreeBSD$ in libc/stdio/rget.c Not objected to: -arch, a few months ago
2001-02-11 22:06:43 +00:00
FUNLOCKFILE(fp);
BSD 4.4 Lite Lib Sources
1994-05-27 05:00:24 +00:00
return (r);
}
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