firmware/events.c

   1 /***************************************************************************
   2  *             __________               __   ___.
   3  *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
   4  *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
   5  *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
   6  *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
   7  *                     \/            \/     \/    \/            \/
   8  * $Id$
   9  *
  10  * Copyright (C) 2008 by Miika Pekkarinen
  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
  20 #include <stdio.h>
  21 #include "events.h"
  22 #include "panic.h"
  23
  24 struct sysevent {
  25     unsigned short id;
  26     bool oneshot;
  27     void (*callback)(void *data);
  28 };
  29
  30 struct sysevent events[MAX_SYS_EVENTS];
  31
  32 bool add_event(unsigned short id, bool oneshot, void (*handler))
  33 {
  34     int i;
  35
  36     /* Check if the event already exists. */
  37     for (i = 0; i < MAX_SYS_EVENTS; i++)
  38     {
  39         if (events[i].callback == handler && events[i].id == id)
  40             return false;
  41     }
  42
  43     /* Try to find a free slot. */
  44     for (i = 0; i < MAX_SYS_EVENTS; i++)
  45     {
  46         if (events[i].callback == NULL)
  47         {
  48             events[i].id = id;
  49             events[i].oneshot = oneshot;
  50             events[i].callback = handler;
  51             return true;
  52         }
  53     }
  54
  55     panicf("event line full");
  56     return false;
  57 }
  58
  59 void remove_event(unsigned short id, void (*handler))
  60 {
  61     int i;
  62
  63     for (i = 0; i < MAX_SYS_EVENTS; i++)
  64     {
  65         if (events[i].id == id && events[i].callback == handler)
  66         {
  67             events[i].callback = NULL;
  68             return;
  69         }
  70     }
  71
  72     panicf("event %d not found", (int)id);
  73 }
  74
  75 void send_event(unsigned short id, void *data)
  76 {
  77     int i;
  78
  79     for (i = 0; i < MAX_SYS_EVENTS; i++)
  80     {
  81         if (events[i].id == id && events[i].callback != NULL)
  82         {
  83             events[i].callback(data);
  84
  85             if (events[i].oneshot)
  86                 events[i].callback = NULL;
  87         }
  88     }
  89 }
  90