1 /* $Id: tape.c,v 1.1 2003/08/05 03:27:12 fredette Exp $ */
2 
3 /* generic/tape.c - generic tape implementation support: */
4 
5 /*
6  * Copyright (c) 2003 Matt Fredette
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. All advertising materials mentioning features or use of this software
18  *    must display the following acknowledgement:
19  *      This product includes software developed by Matt Fredette.
20  * 4. The name of the author may not be used to endorse or promote products
21  *    derived from this software without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
24  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
25  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
26  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
27  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
28  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
29  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
31  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
32  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
33  * POSSIBILITY OF SUCH DAMAGE.
34  */
35 
36 #include <tme/common.h>
37 _TME_RCSID("$Id: tape.c,v 1.1 2003/08/05 03:27:12 fredette Exp $");
38 
39 /* includes: */
40 #include <tme/generic/tape.h>
41 
42 /* this scores a tape connection: */
43 int
tme_tape_connection_score(struct tme_connection * conn,unsigned int * _score)44 tme_tape_connection_score(struct tme_connection *conn,
45 			  unsigned int *_score)
46 {
47   struct tme_tape_connection *conn_tape;
48   struct tme_tape_connection *conn_tape_other;
49 
50   /* both sides must be tape connections: */
51   assert(conn->tme_connection_type == TME_CONNECTION_TAPE);
52   assert(conn->tme_connection_other->tme_connection_type == TME_CONNECTION_TAPE);
53 
54   /* you cannot connect a tape to a tape, or a tape frontend to a tape
55      frontend: */
56   conn_tape = (struct tme_tape_connection *) conn;
57   conn_tape_other = (struct tme_tape_connection *) conn->tme_connection_other;
58   *_score
59     = ((conn_tape->tme_tape_connection_read != NULL
60 	|| conn_tape->tme_tape_connection_write != NULL)
61        != (conn_tape_other->tme_tape_connection_read != NULL
62 	   || conn_tape_other->tme_tape_connection_write != NULL));
63   return (TME_OK);
64 }
65