rom/exec/traphandler.c

   1 /*
   2     Copyright © 1995-2010, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     Desc: Default trap handler
   6     Lang: english
   7 */
   8
   9 #include <exec/alerts.h>
  10 #include <exec/tasks.h>
  11 #include <proto/exec.h>
  12
  13 #include "kernel_cpu.h"
  14
  15 #include "etask.h"
  16 #include "exec_intern.h"
  17 #include "exec_util.h"
  18
  19 /* In original AmigaOS the trap handler is entered in supervisor mode with the
  20  * following on the supervisor stack:
  21  *  0(sp).l = trap#
  22  *  4(sp) Processor dependent exception frame
  23  * In our current implementation we use two pointers on stack. Context structure is
  24  * currently private because it differs even on the same CPU, however i beleive it
  25  * should be changed to some generalized form in order to allow applications (debuggers)
  26  * to use it.
  27  */
  28
  29 void Exec_TrapHandler(ULONG trapNum, struct AROSCPUContext *ctx)
  30 {
  31     struct Task *task = SysBase->ThisTask;
  32     struct IntETask *iet;
  33
  34     /* Our situation is deadend */
  35     trapNum |= AT_DeadEnd;
  36
  37     if (task)
  38     {
  39         /* Get internal task structure */
  40         iet = GetIntETask(task);
  41         /* Protection against double-crash. If the alert code is already specified, we have
  42            a second crash during processing the first one. Then we just pick up initial alert code
  43            and just call Alert(). */
  44         if (iet->iet_AlertCode)
  45             trapNum = iet->iet_AlertCode;
  46         else
  47         {
  48             /* Otherwise we can try to send the crash to user level. Set alert information for the task */
  49 #ifdef GET_PC
  50             iet->iet_AlertLocation = GET_PC(ctx);
  51 #endif
  52
  53 #ifdef SET_PC
  54             iet->iet_AlertCode = trapNum;
  55             /* Make the task to jump to crash handler. We don't care about return address etc because
  56                the alert is deadend anyway. */
  57             SET_PC(ctx, Exec_CrashHandler);
  58             /* Let the task go */
  59             return;
  60 #endif
  61         }
  62     }
  63
  64     Alert(trapNum);
  65 } /* TrapHandler */