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  * This program is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU General Public License
  14  * as published by the Free Software Foundation; either version 2
  15  * of the License, or (at your option) any later version.
  16  *
  17  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
  18  * KIND, either express or implied.
  19  *
  20  ****************************************************************************/
  21 #include <limits.h>
  22 #include "system.h"
  23 #include "config.h"
  24 #include "general.h"
  25
  26 int round_value_to_list32(unsigned long value,
  27                           const unsigned long list[],
  28                           int count,
  29                           bool signd)
  30 {
  31     unsigned long dmin = ULONG_MAX;
  32     int idmin = -1, i;
  33
  34     for (i = 0; i < count; i++)
  35     {
  36         unsigned long diff;
  37
  38         if (list[i] == value)
  39         {
  40             idmin = i;
  41             break;
  42         }
  43
  44         if (signd ? ((long)list[i] < (long)value) : (list[i] < value))
  45             diff = value - list[i];
  46         else
  47             diff = list[i] - value;
  48
  49         if (diff < dmin)
  50         {
  51             dmin = diff;
  52             idmin = i;
  53         }
  54     }
  55
  56     return idmin;
  57 } /* round_value_to_list32 */
  58
  59 /* Number of bits set in src_mask should equal src_list length */
  60 int make_list_from_caps32(unsigned long src_mask,
  61                           const unsigned long *src_list,
  62                           unsigned long caps_mask,
  63                           unsigned long *caps_list)
  64 {
  65     int i, count;
  66     unsigned long mask;
  67
  68     for (mask = src_mask, count = 0, i = 0;
  69          mask != 0;
  70          src_mask = mask, i++)
  71     {
  72         unsigned long test_bit;
  73         mask &= mask - 1;           /* Zero lowest bit set */
  74         test_bit = mask ^ src_mask; /* Isolate the bit */
  75         if (test_bit & caps_mask)   /* Add item if caps has test bit set */
  76             caps_list[count++] = src_list ? src_list[i] : (unsigned long)i;
  77     }
  78
  79     return count;
  80 } /* make_list_from_caps32 */
  81
  82 /* Align a buffer and size to a size boundary while remaining within
  83  * the original boundaries */
  84 size_t align_buffer(void **start, size_t size, size_t align)
  85 {
  86     void *newstart = *start;
  87     void *newend = newstart + size;
  88
  89     /* Align the end down and the start up */
  90     newend = (void *)ALIGN_DOWN((intptr_t)newend, align);
  91     newstart = (void *)ALIGN_UP((intptr_t)newstart, align);
  92
  93     /* Hmmm - too small for this */
  94     if (newend <= newstart)
  95         return 0;
  96
  97     /* Return adjusted pointer and size */
  98     *start = newstart;
  99     return newend - newstart;
 100 }