xref: /illumos-gate/usr/src/contrib/ast/src/lib/libast/disc/sfdcslow.c (revision 2a8bcb4efb45d99ac41c94a75c396b362c414f7f)
1 /***********************************************************************
2 *                                                                      *
3 *               This software is part of the ast package               *
4 *          Copyright (c) 1985-2011 AT&T Intellectual Property          *
5 *                      and is licensed under the                       *
6 *                 Eclipse Public License, Version 1.0                  *
7 *                    by AT&T Intellectual Property                     *
8 *                                                                      *
9 *                A copy of the License is available at                 *
10 *          http://www.eclipse.org/org/documents/epl-v10.html           *
11 *         (with md5 checksum b35adb5213ca9657e911e9befb180842)         *
12 *                                                                      *
13 *              Information and Software Systems Research               *
14 *                            AT&T Research                             *
15 *                           Florham Park NJ                            *
16 *                                                                      *
17 *                 Glenn Fowler <gsf@research.att.com>                  *
18 *                  David Korn <dgk@research.att.com>                   *
19 *                   Phong Vo <kpv@research.att.com>                    *
20 *                                                                      *
21 ***********************************************************************/
22 #include "sfdchdr.h"
23 
24 /*	Make a stream op return immediately on interrupts.
25 **	This is useful on slow streams (hence the name).
26 **
27 **	Written by Glenn Fowler (03/18/1998).
28 */
29 
30 #if __STD_C
31 static int slowexcept(Sfio_t* f, int type, Void_t* v, Sfdisc_t* disc)
32 #else
33 static int slowexcept(f, type, v, disc)
34 Sfio_t*		f;
35 int		type;
36 Void_t*		v;
37 Sfdisc_t*	disc;
38 #endif
39 {
40 	NOTUSED(f);
41 	NOTUSED(v);
42 	NOTUSED(disc);
43 
44 	switch (type)
45 	{
46 	case SF_FINAL:
47 	case SF_DPOP:
48 		free(disc);
49 		break;
50 	case SF_READ:
51 	case SF_WRITE:
52 		if (errno == EINTR)
53 			return(-1);
54 		break;
55 	}
56 
57 	return(0);
58 }
59 
60 #if __STD_C
61 int sfdcslow(Sfio_t* f)
62 #else
63 int sfdcslow(f)
64 Sfio_t*	f;
65 #endif
66 {
67 	Sfdisc_t*	disc;
68 
69 	if(!(disc = (Sfdisc_t*)malloc(sizeof(Sfdisc_t))) )
70 		return(-1);
71 
72 	disc->readf = NIL(Sfread_f);
73 	disc->writef = NIL(Sfwrite_f);
74 	disc->seekf = NIL(Sfseek_f);
75 	disc->exceptf = slowexcept;
76 
77 	if(sfdisc(f,disc) != disc)
78 	{	free(disc);
79 		return(-1);
80 	}
81 	sfset(f,SF_IOINTR,1);
82 
83 	return(0);
84 }
85