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 "system.h"
  21 #include "config.h"
  22 #include "general.h"
  23
  24 int round_value_to_list32(unsigned long value,
  25                           const unsigned long list[],
  26                           int count,
  27                           bool signd)
  28 {
  29     unsigned long dmin = ULONG_MAX;
  30     int idmin = -1, i;
  31
  32     for (i = 0; i < count; i++)
  33     {
  34         unsigned long diff;
  35
  36         if (list[i] == value)
  37         {
  38             idmin = i;
  39             break;
  40         }
  41
  42         if (signd ? ((long)list[i] < (long)value) : (list[i] < value))
  43             diff = value - list[i];
  44         else
  45             diff = list[i] - value;
  46
  47         if (diff < dmin)
  48         {
  49             dmin = diff;
  50             idmin = i;
  51         }
  52     }
  53
  54     return idmin;
  55 } /* round_value_to_list32 */
  56
  57 /* Number of bits set in src_mask should equal src_list length */
  58 int make_list_from_caps32(unsigned long src_mask,
  59                           const unsigned long *src_list,
  60                           unsigned long caps_mask,
  61                           unsigned long *caps_list)
  62 {
  63     int i, count;
  64     unsigned long mask;
  65
  66     for (mask = src_mask, count = 0, i = 0;
  67          mask != 0;
  68          src_mask = mask, i++)
  69     {
  70         unsigned long test_bit;
  71         mask &= mask - 1;           /* Zero lowest bit set */
  72         test_bit = mask ^ src_mask; /* Isolate the bit */
  73         if (test_bit & caps_mask)   /* Add item if caps has test bit set */
  74             caps_list[count++] = src_list ? src_list[i] : (unsigned long)i;
  75     }
  76
  77     return count;
  78 } /* make_list_from_caps32 */
  79
  80 /* Align a buffer and size to a size boundary while remaining within
  81  * the original boundaries */
  82 size_t align_buffer(void **start, size_t size, size_t align)
  83 {
  84     void *newstart = *start;
  85     void *newend = newstart + size;
  86
  87     /* Align the end down and the start up */
  88     newend = (void *)ALIGN_DOWN((intptr_t)newend, align);
  89     newstart = (void *)ALIGN_UP((intptr_t)newstart, align);
  90
  91     /* Hmmm - too small for this */
  92     if (newend <= newstart)
  93         return 0;
  94
  95     /* Return adjusted pointer and size */
  96     *start = newstart;
  97     return newend - newstart;
  98 }