xref: /titanic_41/usr/src/lib/libast/common/sfio/sfgetl.c (revision 7c2fbfb345896881c631598ee3852ce9ce33fb07)
1 /***********************************************************************
2 *                                                                      *
3 *               This software is part of the ast package               *
4 *          Copyright (c) 1985-2008 AT&T Intellectual Property          *
5 *                      and is licensed under the                       *
6 *                  Common Public License, Version 1.0                  *
7 *                    by AT&T Intellectual Property                     *
8 *                                                                      *
9 *                A copy of the License is available at                 *
10 *            http://www.opensource.org/licenses/cpl1.0.txt             *
11 *         (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9)         *
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	"sfhdr.h"
23 
24 /*	Read a long value coded in a portable format.
25 **
26 **	Written by Kiem-Phong Vo
27 */
28 
29 #if __STD_C
30 Sflong_t sfgetl(Sfio_t* f)
31 #else
32 Sflong_t sfgetl(f)
33 Sfio_t*	f;
34 #endif
35 {
36 	Sflong_t	v;
37 	uchar		*s, *ends, c;
38 	int		p;
39 	SFMTXDECL(f);
40 
41 	SFMTXENTER(f,(Sflong_t)(-1));
42 
43 	if(f->mode != SF_READ && _sfmode(f,SF_READ,0) < 0)
44 		SFMTXRETURN(f, (Sflong_t)(-1));
45 	SFLOCK(f,0);
46 
47 	for(v = 0;;)
48 	{	if(SFRPEEK(f,s,p) <= 0)
49 		{	f->flags |= SF_ERROR;
50 			v = (Sflong_t)(-1);
51 			goto done;
52 		}
53 		for(ends = s+p; s < ends;)
54 		{	c = *s++;
55 			if(c&SF_MORE)
56 				v = ((Sfulong_t)v << SF_UBITS) | SFUVALUE(c);
57 			else
58 			{	/* special translation for this byte */
59 				v = ((Sfulong_t)v << SF_SBITS) | SFSVALUE(c);
60 				f->next = s;
61 				v = (c&SF_SIGN) ? -v-1 : v;
62 				goto done;
63 			}
64 		}
65 		f->next = s;
66 	}
67 done :
68 	SFOPEN(f,0);
69 	SFMTXRETURN(f, v);
70 }
71