fdopen.c
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上传日期:2007-04-14
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文件大小:3k
- /*-
- * Copyright (c) 1990 The Regents of the University of California.
- * Copyright (c) 1993, 1994 Chris Provenzano.
- * 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.
- */
- #if defined(LIBC_SCCS) && !defined(lint)
- /*static char *sccsid = "from: @(#)fdopen.c 5.6 (Berkeley) 2/24/91";*/
- static char *rcsid = "$Id$";
- #endif /* LIBC_SCCS and not lint */
- #include <pthread.h>
- #include <sys/types.h>
- #include <fcntl.h>
- #include <unistd.h>
- #include <stdio.h>
- #include <errno.h>
- #include "local.h"
- extern pthread_mutex_t __sfp_mutex;
- extern pthread_cond_t __sfp_cond;
- extern int __sfp_state;
- FILE *fdopen(int fd, const char *mode)
- {
- register FILE *fp;
- int flags, oflags, fdflags, tmp;
- if ((flags = __sflags(mode, &oflags)) == 0)
- return (NULL);
- /* Make sure the mode the user wants is a subset of the actual mode. */
- if ((fdflags = fcntl(fd, F_GETFL, 0)) < 0)
- return (NULL);
- tmp = fdflags & O_ACCMODE;
- if (tmp != O_RDWR && (tmp != (oflags & O_ACCMODE))) {
- errno = EINVAL;
- return (NULL);
- }
- __sinit ();
- pthread_mutex_lock(&__sfp_mutex);
- while (__sfp_state) {
- pthread_cond_wait(&__sfp_cond, &__sfp_mutex);
- }
- if (fp = __sfp()) {
- fp->_flags = flags;
- /*
- * If opened for appending, but underlying descriptor does not have
- * O_APPEND bit set, assert __SAPP so that __swrite() will lseek to
- * end before each write.
- */
- if ((oflags & O_APPEND) && !(fdflags & O_APPEND))
- fp->_flags |= __SAPP;
- fp->_file = fd;
- }
- pthread_mutex_unlock(&__sfp_mutex);
- return (fp);
- }