/*
   ***************************************************************************
   *
   * Datei:
   *      RSysSignalTrap.c
   *
   * Inhalt:
   *
   *      --- Globale Routinen ---
   *
   *    void HandleTrap ( int signal );
   *    void InstallTrapHandlers ( void );
   *    void RemoveTrapHandlers ( void );
   *    void _traphandler ( long sig );
   *
   *      --- Lokale  Routinen ---
   *
   *    static void ( *_sigfuncs [_NUMSIG ]);
   *    static void convert ( ULONG state , char *str );
   *
   * Bemerkungen:
   *      Verwaltung eines Traphandlers, um RSys wirklich (?) absturzsicher
   *      zu machen.
   *
   * Erstellungsdatum:
   *      07-Jul-93     Rolf Böhme
   *
   * Änderungen:
   *      07-Jul-93     Rolf Böhme        Erstellung
   *
   ***************************************************************************
 */

#include "RSys.h"
#include "protos.h"

/*
   #define SIG_BEGINSSP                 0
   #define SIG_BEGINPC                  1
   #define SIG_BUSERROR                 2
   #define SIG_ADDRERROR                3
   #define SIG_ILLCOMM                  4
   #define SIG_DIVZERO                  5
   #define SIG_CHKERROR                 6
   #define SIG_TRAPV                    7
   #define SIG_VIOLPRIV                 8
   #define SIG_TRACE                    9
   #define SIG_LINEAEMUL                10
   #define SIG_LINEFEMUL                11
   #define SIG_NOTDEF                   12
   #define SIG_COPROPROT                13
   #define SIG_FORMATERR                14
   #define SIG_INTRFAIL                 15

   #define SIG_MC_ILLCOND               48
   #define SIG_MC_ILLRESULT     49
   #define SIG_MC_DIVZERO               50
   #define SIG_MC_UNDERFLOW     51
   #define SIG_MC_OPERROR               52
   #define SIG_MC_OVERFLOW      53
   #define SIG_MC_NANSIG                54
   #define SIG_MC_NOTDEF                55
 */

static void (*_sigfuncs[_NUMSIG]) (int);
int _trapexception (void);
int _initfpu (void);
void *_oldtrap, **_trapaddr;

static TASK *tp;

char *TrapCPUMsg[] =
{
  "Begin of SSP (ISP by 680x0)",
  "Begin of PC",
  "Bus error",
  "Address error",
  "Illegal or unknown instruction",
  "Division by zero or arithmetic fault",
  "CHK and CHK2 affected",
  "TRAP or TRAPV reached",
  "Priviledge violation",
  "Trace error",
  "Line A Emulator, illegal Opcode by MC68000",
  "Line F Emulator, illegal Opcode by MC68000",
  "Error is reserved",
  "Coprocessor protocol error",
  "Format error by MC680x0",
  "Uninitialized Interrupt"
};

 /*
  * convert() konvertiert eine 32Bit-Zahl in einen
  * "Binärstring", also in einen String, der nur aus '0'
  * und '1' besteht
  */
static void
convert (ULONG state, char *str)
{
  int bit;

  for (bit = 0; bit < 32; bit++)
    str[31 - bit] = ((state & (1L << bit)) ? '1' : '0');

  str[32] = STRINGEND;

}

 /*
  * HandleTrap() ist die Funktion, die im Falle eines
  * System traps aktiviert wird. Diese Routine ruft
  * entweder den System debugger ROMWack auf, oder
  * verursacht einen Kaltstart des Rechners, falls dies
  * gewünscht wird. Installiert wird diese Routine
  * mit der ANSI-Routine signal() des
  * Aztec-C-Compilers
  */
void
HandleTrap (int signal)
{
  int action;
  char exceptstr[33], signalstr[33], statestr[33];
  UBYTE *fmt = (UBYTE *) "Error signal: %s (%ld)\n"
  "Exception   : %s (0x%08lX)\n"
  "Task signal : %s (0x%08lX)\n"
  "CPU Status  : %s (0x%08lX)\n"
  "Trap data   : %08lX\n"
  "Except data : %08lX\n";
  ULONG exc, sig, sta;
  APTR UserStack;

  UserStack = SuperState ();

  exc = SetExcept (0L, 0L);
  sig = SetSignal (0L, 0L);
  sta = SetSR (0L, 0L);

  UserState (UserStack);

  convert (exc, exceptstr);
  convert (sig, signalstr);
  convert (sta, statestr);

  if (IntuitionBase != NULL)
    action = MyEasyRequest (NULL,
		   (UBYTE *) NAME " *** Emergency trap failure message ***",
     (UBYTE *) "Continue|Terminate RSys|Call system debugger|Reboot system",
			    fmt, TrapCPUMsg[signal], signal,
			    exceptstr, exc, signalstr, sig, statestr, sta,
			    tp->tc_TrapData, tp->tc_ExceptData);
  else
    {
      action = -1;
      Printf (fmt, (ULONG) TrapCPUMsg[signal], signal,
	      exceptstr, exc, signalstr, sig, statestr, sta,
	      tp->tc_TrapData, tp->tc_ExceptData);
    }

  switch (action)
    {
    case -1:
      exit (0);
      break;

    case 0:
      ColdReboot ();
      break;

    case 1:
      break;

    case 2:
      CloseAll ();
      break;

    case 3:
      Debug (0L);
      CloseAll ();
      break;
    }

}

 /*
  * InstallTrapHandlers() installiert einen Traphandler,
  * der auf verschiedene Traps reagieren kann
  */
void
InstallTrapHandlers (void)
{
  int i;

  tp = FindTask (NULL);

  Forbid ();

  _trapaddr = (void *) &tp->tc_TrapCode;
  _oldtrap = tp->tc_TrapCode;

  tp->tc_TrapCode = (APTR) & _trapexception;

  if (SysBase->AttnFlags & AFF_68881)
    _initfpu ();

  for (i = _FSTSIG; i <= _NUMSIG; i++)
    _sigfuncs[i] = HandleTrap;

  Permit ();

}

void
RemoveTrapHandlers (void)
{
  int i;

  Forbid ();

  if (_trapaddr)
    *_trapaddr = _oldtrap;

  for (i = _FSTSIG; i <= _NUMSIG; i++)
    _sigfuncs[i] = NULL;

  Permit ();

}

void
_traphandler (long sig)
{
  void (*handler) (int);

  if ((handler = _sigfuncs[sig]) != NULL)
    (*handler) (sig);

}