xref: /onnv-gate/usr/src/lib/libbc/libc/gen/common/l64a.c (revision 0:68f95e015346)
1*0Sstevel@tonic-gate /*
2*0Sstevel@tonic-gate  * CDDL HEADER START
3*0Sstevel@tonic-gate  *
4*0Sstevel@tonic-gate  * The contents of this file are subject to the terms of the
5*0Sstevel@tonic-gate  * Common Development and Distribution License, Version 1.0 only
6*0Sstevel@tonic-gate  * (the "License").  You may not use this file except in compliance
7*0Sstevel@tonic-gate  * with the License.
8*0Sstevel@tonic-gate  *
9*0Sstevel@tonic-gate  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10*0Sstevel@tonic-gate  * or http://www.opensolaris.org/os/licensing.
11*0Sstevel@tonic-gate  * See the License for the specific language governing permissions
12*0Sstevel@tonic-gate  * and limitations under the License.
13*0Sstevel@tonic-gate  *
14*0Sstevel@tonic-gate  * When distributing Covered Code, include this CDDL HEADER in each
15*0Sstevel@tonic-gate  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16*0Sstevel@tonic-gate  * If applicable, add the following below this CDDL HEADER, with the
17*0Sstevel@tonic-gate  * fields enclosed by brackets "[]" replaced with your own identifying
18*0Sstevel@tonic-gate  * information: Portions Copyright [yyyy] [name of copyright owner]
19*0Sstevel@tonic-gate  *
20*0Sstevel@tonic-gate  * CDDL HEADER END
21*0Sstevel@tonic-gate  */
22*0Sstevel@tonic-gate /*      Copyright (c) 1984 AT&T */
23*0Sstevel@tonic-gate /*        All Rights Reserved   */
24*0Sstevel@tonic-gate 
25*0Sstevel@tonic-gate #pragma ident	"%Z%%M%	%I%	%E% SMI"  /* from S5R2 1.5 */
26*0Sstevel@tonic-gate 
27*0Sstevel@tonic-gate /*LINTLIBRARY*/
28*0Sstevel@tonic-gate /*
29*0Sstevel@tonic-gate  * convert long int to base 64 ascii
30*0Sstevel@tonic-gate  * char set is [./0-9A-Za-z]
31*0Sstevel@tonic-gate  * two's complement negatives are assumed,
32*0Sstevel@tonic-gate  * but no assumptions are made about sign propagation on right shift
33*0Sstevel@tonic-gate  *
34*0Sstevel@tonic-gate  */
35*0Sstevel@tonic-gate 
36*0Sstevel@tonic-gate #include <values.h>
37*0Sstevel@tonic-gate #define BITSPERCHAR	6 /* to hold entire character set */
38*0Sstevel@tonic-gate #define BITSPERLONG	(BITSPERBYTE * sizeof(long))
39*0Sstevel@tonic-gate #define NMAX	((BITSPERLONG + BITSPERCHAR - 1)/BITSPERCHAR)
40*0Sstevel@tonic-gate #define SIGN	(-(1L << (BITSPERLONG - BITSPERCHAR - 1)))
41*0Sstevel@tonic-gate #define CHARMASK	((1 << BITSPERCHAR) - 1)
42*0Sstevel@tonic-gate #define WORDMASK	((1L << ((NMAX - 1) * BITSPERCHAR)) - 1)
43*0Sstevel@tonic-gate 
44*0Sstevel@tonic-gate static char buf[NMAX + 1];
45*0Sstevel@tonic-gate 
46*0Sstevel@tonic-gate char *
l64a(lg)47*0Sstevel@tonic-gate l64a(lg)
48*0Sstevel@tonic-gate register long lg;
49*0Sstevel@tonic-gate {
50*0Sstevel@tonic-gate 	register char *s = buf;
51*0Sstevel@tonic-gate 
52*0Sstevel@tonic-gate 	while (lg != 0) {
53*0Sstevel@tonic-gate 
54*0Sstevel@tonic-gate 		register int c = ((int)lg & CHARMASK) + ('0' - 2);
55*0Sstevel@tonic-gate 
56*0Sstevel@tonic-gate 		if (c > '9')
57*0Sstevel@tonic-gate 			c += 'A' - '9' - 1;
58*0Sstevel@tonic-gate 		if (c > 'Z')
59*0Sstevel@tonic-gate 			c += 'a' - 'Z' - 1;
60*0Sstevel@tonic-gate 		*s++ = c;
61*0Sstevel@tonic-gate 		/* fill high-order CHAR if negative */
62*0Sstevel@tonic-gate 		/* but suppress sign propagation */
63*0Sstevel@tonic-gate 		lg = ((lg < 0) ? (lg >> BITSPERCHAR) | SIGN :
64*0Sstevel@tonic-gate 			lg >> BITSPERCHAR) & WORDMASK;
65*0Sstevel@tonic-gate 	}
66*0Sstevel@tonic-gate 	*s = '\0';
67*0Sstevel@tonic-gate 	return (buf);
68*0Sstevel@tonic-gate }
69