xref: /onnv-gate/usr/src/lib/libast/common/disc/sfdctee.c (revision 4887:feebf9260c2e)
1*4887Schin /***********************************************************************
2*4887Schin *                                                                      *
3*4887Schin *               This software is part of the ast package               *
4*4887Schin *           Copyright (c) 1985-2007 AT&T Knowledge Ventures            *
5*4887Schin *                      and is licensed under the                       *
6*4887Schin *                  Common Public License, Version 1.0                  *
7*4887Schin *                      by AT&T Knowledge Ventures                      *
8*4887Schin *                                                                      *
9*4887Schin *                A copy of the License is available at                 *
10*4887Schin *            http://www.opensource.org/licenses/cpl1.0.txt             *
11*4887Schin *         (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9)         *
12*4887Schin *                                                                      *
13*4887Schin *              Information and Software Systems Research               *
14*4887Schin *                            AT&T Research                             *
15*4887Schin *                           Florham Park NJ                            *
16*4887Schin *                                                                      *
17*4887Schin *                 Glenn Fowler <gsf@research.att.com>                  *
18*4887Schin *                  David Korn <dgk@research.att.com>                   *
19*4887Schin *                   Phong Vo <kpv@research.att.com>                    *
20*4887Schin *                                                                      *
21*4887Schin ***********************************************************************/
22*4887Schin #include	"sfdchdr.h"
23*4887Schin 
24*4887Schin /*	A discipline to tee the output to a stream to another stream.
25*4887Schin **	This is similar to what the "tee" program does. As implemented
26*4887Schin **	this discipline only works with file streams.
27*4887Schin **
28*4887Schin **	Written by Kiem-Phong Vo, kpv@research.att.com, 03/18/1998.
29*4887Schin */
30*4887Schin 
31*4887Schin /* the discipline structure for tee-ing */
32*4887Schin typedef struct _tee_s
33*4887Schin {	Sfdisc_t	disc;	/* the sfio discipline structure */
34*4887Schin 	Sfio_t*		tee;	/* the stream to tee to */
35*4887Schin 	int		status;	/* if tee stream is still ok */
36*4887Schin } Tee_t;
37*4887Schin 
38*4887Schin /*	write to the teed stream.  */
39*4887Schin #if __STD_C
40*4887Schin static ssize_t teewrite(Sfio_t* f, const Void_t* buf, size_t size, Sfdisc_t* disc)
41*4887Schin #else
42*4887Schin static ssize_t teewrite(f,buf,size,disc)
43*4887Schin Sfio_t* 	f;	/* the stream being written to */
44*4887Schin Void_t*		buf;	/* the buffer of data being output */
45*4887Schin size_t		size;	/* the data size */
46*4887Schin Sfdisc_t*	disc;	/* the tee discipline */
47*4887Schin #endif
48*4887Schin {
49*4887Schin 	reg Tee_t*	te = (Tee_t*)disc;
50*4887Schin 
51*4887Schin 	/* tee data if still ok */
52*4887Schin 	if(te->status == 0 && sfwrite(te->tee,buf,size) != (ssize_t)size)
53*4887Schin 		te->status = -1;
54*4887Schin 
55*4887Schin 	/* do the actual write */
56*4887Schin 	return sfwr(f,buf,size,disc);
57*4887Schin }
58*4887Schin 
59*4887Schin /* on close, remove the discipline */
60*4887Schin #if __STD_C
61*4887Schin static int teeexcept(Sfio_t* f, int type, Void_t* data, Sfdisc_t* disc)
62*4887Schin #else
63*4887Schin static int teeexcept(f,type,data,disc)
64*4887Schin Sfio_t*		f;
65*4887Schin int		type;
66*4887Schin Void_t*		data;
67*4887Schin Sfdisc_t*	disc;
68*4887Schin #endif
69*4887Schin {
70*4887Schin 	if(type == SF_FINAL || type == SF_DPOP)
71*4887Schin 		free(disc);
72*4887Schin 
73*4887Schin 	return 0;
74*4887Schin }
75*4887Schin 
76*4887Schin #if __STD_C
77*4887Schin int sfdctee(Sfio_t* f, Sfio_t* tee)
78*4887Schin #else
79*4887Schin int sfdctee(f, tee)
80*4887Schin Sfio_t*	f;	/* stream to tee from	*/
81*4887Schin Sfio_t*	tee;	/* stream to tee to	*/
82*4887Schin #endif
83*4887Schin {
84*4887Schin 	reg Tee_t*	te;
85*4887Schin 
86*4887Schin 	if(!(te = (Tee_t*)malloc(sizeof(Tee_t))) )
87*4887Schin 		return -1;
88*4887Schin 
89*4887Schin 	te->disc.readf = NIL(Sfread_f);
90*4887Schin 	te->disc.seekf = NIL(Sfseek_f);
91*4887Schin 	te->disc.writef = teewrite;
92*4887Schin 	te->disc.exceptf = teeexcept;
93*4887Schin 	te->tee = tee;
94*4887Schin 	te->status = 0;
95*4887Schin 
96*4887Schin 	if(sfdisc(f,(Sfdisc_t*)te) != (Sfdisc_t*)te)
97*4887Schin 	{	free(te);
98*4887Schin 		return -1;
99*4887Schin 	}
100*4887Schin 
101*4887Schin 	return 0;
102*4887Schin }
103