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/*-
 * 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);
}