fd.h

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/* ==== fd.h ============================================================
 * Copyright (c) 1993, 1994 by Chris Provenzano, [e-mail]
 * All rights reserved.
 *
 * 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 Chris Provenzano.
 * 4. The name of Chris Provenzano may not be used to endorse or promote 
 *	  products derived from this software without specific prior written
 *	  permission.
 *
 * THIS SOFTWARE IS PROVIDED BY CHRIS PROVENZANO ``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 CHRIS PROVENZANO 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.
 *
 * $Id$
 *
 * Description : Basic fd header.
 *
 *  1.00 93/08/14 proven
 *      -Started coding this file.
 *
 *	1.01 93/11/13 proven
 *		-The functions readv() and writev() added
 */

/*
 * New pthread types.
 */
enum fd_type {
	FD_NT,					/* Not tested */
	FD_NIU,					/* Known to be not in use */
	FD_HALF_DUPLEX,			/* Files, and seeking devices */
	FD_FULL_DUPLEX,			/* pipes, sockets, drivers, ... */
	FD_TEST_HALF_DUPLEX,	/* Redo machdep_sys_fcntl */
	FD_TEST_FULL_DUPLEX	/* Redo machdep_sys_fcntl */
};


#define FD_READ				0x1
#define FD_WRITE			0x2
#define FD_RDWR				(FD_READ | FD_WRITE)

union fd_data {
	void 					*ptr;
	int						i;
};

struct timespec;
struct iovec;
struct fd_ops {
	pthread_ssize_t 		(*write) __P_((union fd_data, int, const void *,
										  size_t, struct timespec *));
	pthread_ssize_t 		(*read) __P_((union fd_data, int, void *, size_t,
										 struct timespec *));
	int						(*close)();
	int						(*fcntl)();
	int						(*writev) __P_((union fd_data, int,
										   const struct iovec *,
										   int, struct timespec *));
	int						(*readv) __P_((union fd_data, int,
										  const struct iovec *,
										  int, struct timespec *));
	off_t					(*seek)();
	int						use_kfds;
};

struct fd_table_entry {
	struct pthread_queue	r_queue;
	struct pthread_queue	w_queue;
	struct pthread			*r_owner;
	struct pthread			*w_owner;
	pthread_mutex_t			mutex;
	struct fd_table_entry	*next;
	struct fd_ops			*ops;
	enum fd_type			type;
	int						r_lockcount;		/* Count for FILE read locks */
	int						w_lockcount;		/* Count for FILE write locks */
	int						count;

	/* data that needs to be passed to the type dependent fd */
	int						flags;
	union fd_data			fd;
};

/*
 * Globals
 */
#if defined(PTHREAD_KERNEL)

extern struct fd_table_entry **fd_table;
extern int dtablesize;

#endif

/*
 * New functions
 */

__BEGIN_DECLS

#if defined(PTHREAD_KERNEL)

#endif

__END_DECLS