firmware/general.c

   1 /***************************************************************************
   2  *             __________               __   ___.
   3  *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
   4  *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
   5  *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
   6  *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
   7  *                     \/            \/     \/    \/            \/
   8  * $Id$
   9  *
  10  * Copyright (C) 2006 by Michael Sevakis
  11  *
  12  * All files in this archive are subject to the GNU General Public License.
  13  * See the file COPYING in the source tree root for full license agreement.
  14  *
  15  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
  16  * KIND, either express or implied.
  17  *
  18  ****************************************************************************/
  19 #include <limits.h>
  20 #include "config.h"
  21 #include "general.h"
  22
  23 int round_value_to_list32(unsigned long value,
  24                           const unsigned long list[],
  25                           int count,
  26                           bool signd)
  27 {
  28     unsigned long dmin = ULONG_MAX;
  29     int idmin = -1, i;
  30
  31     for (i = 0; i < count; i++)
  32     {
  33         unsigned long diff;
  34
  35         if (list[i] == value)
  36         {
  37             idmin = i;
  38             break;
  39         }
  40
  41         if (signd ? ((long)list[i] < (long)value) : (list[i] < value))
  42             diff = value - list[i];
  43         else
  44             diff = list[i] - value;
  45
  46         if (diff < dmin)
  47         {
  48             dmin = diff;
  49             idmin = i;
  50         }
  51     }
  52
  53     return idmin;
  54 } /* round_value_to_list32 */
  55
  56 /* Number of bits set in src_mask should equal src_list length */
  57 int make_list_from_caps32(unsigned long src_mask,
  58                           const unsigned long *src_list,
  59                           unsigned long caps_mask,
  60                           unsigned long *caps_list)
  61 {
  62     int i, count;
  63     unsigned long mask;
  64
  65     for (mask = src_mask, count = 0, i = 0;
  66          mask != 0;
  67          src_mask = mask, i++)
  68     {
  69         unsigned long test_bit;
  70         mask &= mask - 1;           /* Zero lowest bit set */
  71         test_bit = mask ^ src_mask; /* Isolate the bit */
  72         if (test_bit & caps_mask)   /* Add item if caps has test bit set */
  73             caps_list[count++] = src_list ? src_list[i] : (unsigned long)i;
  74     }
  75
  76     return count;
  77 } /* make_list_from_caps32 */