xref: /titanic_41/usr/src/lib/libbc/libc/gen/common/mallopt.c (revision e4b86885570d77af552e9cf94f142f4d744fb8c8)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 1986 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 #include "mallint.h"
30 #include <errno.h>
31 
32 /*
33  * mallopt -- System V-compatible malloc "optimizer"
34  */
35 int
36 mallopt(int cmd, int value)
37 {
38 	if (__mallinfo.smblks != 0)
39 		return (-1);		/* small block has been allocated */
40 
41 	switch (cmd) {
42 	case M_MXFAST:		/* small block size */
43 		if (value < 0)
44 			return (-1);
45 		__mallinfo.mxfast = value;
46 		break;
47 
48 	case M_NLBLKS:		/* # small blocks per holding block */
49 		if (value <= 0)
50 			return (-1);
51 		__mallinfo.nlblks = value;
52 		break;
53 
54 	case M_GRAIN:		/* small block rounding factor */
55 		if (value <= 0)
56 			return (-1);
57 		/* round up to multiple of minimum alignment */
58 		__mallinfo.grain = roundup(value, ALIGNSIZ);
59 		break;
60 
61 	case M_KEEP:		/* Sun algorithm always preserves data */
62 		break;
63 
64 	default:
65 		return (-1);
66 	}
67 
68 	/* make sure that everything is consistent */
69 	__mallinfo.mxfast = roundup(__mallinfo.mxfast, __mallinfo.grain);
70 
71 	return (0);
72 }
73 
74 
75 /*
76  * mallinfo -- System V-compatible malloc information reporter
77  */
78 struct mallinfo
79 mallinfo(void)
80 {
81 	struct mallinfo mi;
82 
83 	mi = __mallinfo;
84 	mi.uordblks = mi.uordbytes - (mi.allocated * sizeof(uint));
85 	mi.fordblks = mi.arena - (mi.treeoverhead + mi.uordblks +
86 					    (mi.ordblks * sizeof(uint)));
87 	return (mi);
88 }
89