usr/src/lib/libbc/libc/gen/common/mallopt.c

   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 }