arch/i386-darwin/exec/exception.c

   1 /*
   2     Copyright © 1995-2007, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     Desc: Exception - Perform a task exception.
   6     Lang: english
   7 */
   8 #include <exec/execbase.h>
   9 #include <aros/asmcall.h>
  10 #include <proto/kernel.h>
  11 #include <aros/kernel.h>
  12 #include <proto/arossupport.h>
  13
  14 #include <signal.h>
  15 #include <unistd.h>
  16
  17 /*****i*************************************************************************
  18
  19     NAME */
  20 #include <proto/exec.h>
  21
  22         AROS_LH0(void, Exception,
  23
  24 /*  LOCATION */
  25         struct ExecBase *, SysBase, 11, Exec)
  26
  27 /*  FUNCTION
  28         Exception handler. This function is called by the kernel if
  29         a task exception has occured. It is called in the Disable()'d
  30         state so that all signals are still unchanged.
  31
  32         TF_EXCEPT is still set and must be reset by this routine.
  33
  34         The user supplied exception code is called with the
  35         following parameters:
  36
  37             D0  -   Mask of Flags which caused this exception.
  38             A1  -   Task->tc_ExceptData
  39             A6  -   SysBase
  40
  41     INPUTS
  42
  43     RESULT
  44
  45     NOTES
  46         Exec internal function.
  47
  48     EXAMPLE
  49
  50     BUGS
  51
  52     SEE ALSO
  53         Dispatch()
  54
  55     INTERNALS
  56         At the end of this routine we set task->tc_State to TS_EXCEPT so the
  57         the kernel knows it can restore the signaled task context and set it
  58         to TS_RUN again.
  59
  60 ******************************************************************************/
  61 {
  62     AROS_LIBFUNC_INIT
  63
  64   KRNWireImpl(SoftEnable);
  65   KRNWireImpl(SoftCause);
  66
  67   struct Task * task = FindTask(NULL);
  68     BYTE nestCnt;
  69     ULONG flags;
  70
  71     task->tc_Flags &= ~TF_EXCEPT;
  72
  73     nestCnt = SysBase->IDNestCnt;
  74     SysBase->IDNestCnt = 0;
  75
  76     if ((flags = (task->tc_SigExcept & task->tc_SigRecvd)))
  77     {
  78         /* Call the Exception with the new AROS ASMCALL macros */
  79         if (task->tc_ExceptCode != NULL)
  80         {
  81             /* Block the signals we are handling now. The exception handler
  82                we are calling shall restore them.
  83             */
  84             task->tc_SigExcept ^= flags;
  85
  86             Enable();
  87             task->tc_SigExcept |= AROS_UFC3(ULONG, task->tc_ExceptCode,
  88                 AROS_UFCA(ULONG,             flags,               D0),
  89                 AROS_UFCA(APTR,              task->tc_ExceptData, A1),
  90                 AROS_UFCA(struct ExecBase *, SysBase,             A6)
  91             );
  92             Disable();
  93         }
  94         else
  95         {
  96             /* We don't have an exception handler, we shouldn't have
  97                any exceptions. Clear them.
  98             */
  99
 100             task->tc_SigExcept = 0;
 101         }
 102     }
 103
 104     task->tc_State = TS_EXCEPT;
 105
 106     SysBase->IDNestCnt = nestCnt;
 107
 108     /* Enter the kernel. We use an endless loop just in case the
 109        signal handler returns us to this point for whatever reason.
 110     */
 111     while (TRUE)
 112     {
 113           CALLHOOKPKT(krnSoftEnableImpl,0,0);
 114           CALLHOOKPKT(krnSoftCauseImpl,0,0);
 115     }
 116
 117     AROS_LIBFUNC_EXIT
 118 } /* Exception */