/**************************************************************** * TrapIt * * by David M. Balean, 1993 * * * * This program demonstrates a method of handling CPU * * exceptions from a C program. * ****************************************************************/ #include #include #include #include #include /* for getreg */ #include extern char *_ProgramName; char __stdiowin[] = "CON:0/0/620/240/"; char __stdiov37[] = "/CLOSE"; /* prototypes */ /* various bits of code to create CPU exceptions */ extern VOID address_exc(VOID), illegal_exc(VOID), div0_exc(VOID); extern VOID chk_exc(VOID),trapv_exc(VOID),privelege_exc(VOID),trace_exc(VOID); extern VOID A_Line_exc(VOID), F_Line_exc(VOID), trap1_exc(VOID); VOID ExitInitTrap(VOID); /* Clean-up function */ VOID (*func[])(VOID); /* Array of function pointers */ VOID ClearUp(VOID); VOID (*TrapFunc[])(...); VOID ElseWhere(char *s); VOID InLineFunction(VOID); struct Task *MyTask, *FindTask(); /* reg_pc the return address reg_CCR user status reg_d0...d7 all the data registers reg_a0...a7 all the address registers fp0...fp7 all the floating point registers res_num the number of times it has been restored, max 0xffffffff */ struct TrapEnvironment { APTR reg_pc; WORD reg_CCR; LONG reg_d0, reg_d1, reg_d2, reg_d3, reg_d4, reg_d5, reg_d6, reg_d7; LONG reg_a0, reg_a1, reg_a2, reg_a3, reg_a4, reg_a5, reg_a6, reg_a7; LONG fp0[3], fp1[3], fp2[3], fp3[3], fp4[3], fp5[3], fp6[3], fp7[3]; ULONG res_mum; }; /*** NOTE: The FPCP has more registers than this! Probably unimportant There are also: FPCR (32 bit floating point control register) FPSR (32 bit floating point status register) FPIAR (32 bit floating point instruction address register) ***/ struct TrapIt { ULONG trapnum; ULONG ilnumber; ULONG numcalls; APTR oldtrap; APTR ilfunc; /* These are the available functions */ UWORD trapit[63]; /* should be hidden from user */ UWORD restore[2]; UWORD restore_a0[31]; UWORD save_env[13]; UWORD save_env_a0[39]; UWORD set_init_trap[10]; UWORD set_iltrap[34]; UWORD set_ilnumber[7]; UWORD clear_iltrap[13]; UWORD clear_init_trap[13]; UWORD free_trap[23]; /* The initial environment and the inline environment */ struct TrapEnvironment initenv; struct TrapEnvironment inlineenv; }; static struct TrapIt MyTrap = { 0, /* errnum ds.l 1 trap number goes here */ 0, /* ilnumber ds.l 1 for user use e.g. line number */ 0, /* numcalls ds.l 1 number of times inline called */ NULL, /* oldtrap ds.l 1 old pointer, filled in later */ NULL, /* ilfunc ds.l 1 pointer to user inline function */ 0x0C97, 0x0000, 0x0040, /* trapit cmp.l #64,(a7) */ 0x6410, /* bcc.b .NotTrapped */ 0x0C97, 0x0000, 0x0019, /* cmp.l #25,(a7) */ 0x650E, /* bcs.b .Trapped */ 0x0C97, 0x0000, 0x0020, /* cmp.l #32,(a7) */ 0x6406, /* bcc.b .Trapped */ 0x2F3A, 0xFFDE, /* .NotTrapped move.l oldtrap(pc),-(a7)*/ 0x4E75, /* rts */ 0x201F, /* .Trapped move.l (a7)+,d0 */ 0x41FA, 0xFFCA, /* lea.l errnum(pc),a0 */ 0x2080, /* move.l d0,(a0) */ 0x2078, 0x0004, /* movea.l (4).w,a0 */ 0x3228, 0x0128, /* move.w $128(a0),d1 */ 0x0281, 0x0000, 0x000F, /* and.l #$0f,d1 */ 0x660C, /* bne.b .NOT68000 */ 0xB07C, 0x0004, /* .MR68000 cmp.w #4,d0 */ 0x6402, /* bcc.b .NOTaddress */ 0x504F, /* addq.w #8,a7 */ 0x7206, /* .NOTaddress moveq.l #6,d1 */ 0x6012, /* bra.b .donetrap */ 0x41FA, 0x006C, /* .NOT68000 lea.l Xtable(pc),a0 */ 0x322F, 0x0006, /* move.w $06(a7),d1 */ 0x0241, 0xF000, /* andi.w #$f000,d1 */ 0xE959, /* rol.w #4,d1 */ 0xD0C1, /* add.w d1,a0 */ 0x1210, /* move.b (a0),d1 */ 0x3017, /* .donetrap move.w (a7),d0 */ 0xDEC1, /* add.w d1,a7 */ 0x0240, 0x5FFF, /* andi.w #$5fff,d0 */ 0x46C0, /* move.w d0,SR */ 0x203A, 0xFF9C, /* move.l ilfunc(pc),d0 */ 0x6714, /* beq.b .initenv */ 0x43FA, 0xFF8E, /* lea.l numcalls(pc),a1 */ 0x5291, /* addq.l #1,(a1) */ 0x6602, /* bne.b .calls_ok */ 0x5391, /* subq.l #1,(a1) */ 0x2040, /* .calls_ok movea.l d0,a0 */ 0x4E90, /* jsr (a0) */ 0x41FA, 0x0226, /* lea.l inlineenv(pc),a0*/ 0x600A, /* bra.b restore_a0 */ 0x41FA, 0x0176, /* .initenv lea.l initenv(pc),a0 */ 0x6004, /* bra.b restore_a0 */ /* trapit = 63 WORDS */ 0x206F, 0x0004, /* restore movea.l 4(a7)+,a0 */ /* resore = 2 WORDS */ 0x2278, 0x0004, /* restore_a0 movea.l (4).w,a1 */ 0x0829, 0x0004, 0x0129, /* btst.b #4,$129(a1) */ 0x6706, /* beq.b .skip */ 0xF228, 0xD0FF, 0x0046, /* fmovem.x reg_fp0(a0),fp0-fp7 */ 0x2268, 0x0042, /* .skip move.l reg_a7(a0),a1 */ 0x2290, /* move.l (a0),(a1) */ 0x52A8,0x00A6, /* addq.l #1,res_num(a0) */ 0x6604, /* bne.b .res_num_ok */ 0x53A8,0x00A6, /* subq.l #1,res_num(a0) */ 0x44E8, 0x0004, /* .res_num_ok move.w reg_CCR(a0),CCR */ 0x4CE8, 0xFFFF, 0x0006, /* movem.l reg_d0(a0),d0-d7/a0-a7 */ 0x4E75, /* rts */ 0x0808, /* Xtable dc.b 8,8 */ 0x0C00, /* dc.b 12,0 */ 0x0000, /* dc.b 0,0 */ 0x0000, /* dc.b 0,0 */ 0x3A14, /* dc.b 58,20 */ 0x205C, /* dc.b 32,92 */ 0x0000, /* dc.b 0,0 */ 0x0000, /* dc.b 0,0 */ /* restore_a0 = 31 WORDS */ 0x48E7, 0x0080, /* save_env movem.l a0,-(a7) */ 0x4CEF, 0x0100, 0x0008, /* movem.l 4+4(a7),a0 */ 0x610E, /* bsr.b save_env_a0 */ 0x216F, 0x0004, 0x0000, /* move.l 4(a7),reg_pc(a0)*/ 0x44E8, 0x0004, /* move.w reg_CCR(a0),CCR */ 0x205F, /* movea.l (a7)+,a0 */ 0x4E75, /* rts */ /* save_env = 13 WORDS */ 0x48E7, 0xC042, /*save_env_a0 movem.l d0-d1/a1/a6,-(a7)*/ 0x48E7, 0x0080, /* movem.l a0,-(a7) */ 0x2C78, 0x0004, /* movea.l (4).w,a6 */ 0x4EAE, 0xFDF0, /* jsr $fffffdf0(a6) */ 0x205F, /* movea.l (a7)+,a0 */ 0x3140, 0x0004, /* move.w d0,reg_CCR(a0) */ 0x4CDF, 0x4203, /* movem.l (a7)+,d0-d1/a1/a6 */ 0x2097, /* move.l (a7),(a0) */ 0x48E8, 0x00FF, 0x0006, /* movem.l d0-d7,reg_d0(a0)*/ 0x216F, 0x0004, 0x0026, /* move.l 4(a7),reg_a0(a0)*/ 0x48E8, 0xFE00, 0x002A, /* movem.l a1-a7,reg_a1(a0)*/ 0x50A8, 0x0042, /* addq.l #8,reg_a7(a0) */ 0x2278, 0x0004, /* movea.l (4).w,a1 */ 0x0829, 0x0004, 0x0129, /* btst.b #4,$129(a1) */ 0x6706, /* beq.b .skip */ 0xF228, 0xF0FF, 0x0046, /* fmovem.x fp0-fp7,reg_fp0(a0) */ 0x44E8, 0x0004, /* .skip move.w reg_CCR(a0),CCR */ 0x2268, 0x002A, /* movea.l reg_a1(a0),a1 */ 0x4E75, /* rts */ /* save_env_a0 = 39 WORDS */ 0x48E7, 0x0080, /* set_init_trap movem.l a0,-(a7) */ 0x41FA, 0x00C2, /* lea.l initenv(pc),a0 */ 0x61A8, /* bsr.b save_env_a0 */ 0x20AF, 0x0008, /* move.l 4+4(a7),(a0) */ 0x6126, /* bsr.b put_trap */ 0x205F, /* movea.l (a7)+,a0 */ 0x4E75, /* rts */ /* set_init_trap = 10 WORDS */ 0x48E7, 0x0080, /* set_iltrap movem.l a0,-(a7) */ 0x41FA, 0x0158, /* lea.l inlineenv(pc),a0*/ 0x6194, /* bsr.b save_env_a0 */ 0x20AF, 0x0004, /* move.l 4(a7),(a0) */ 0x41FA, 0xFEB0, /* lea.l ilfunc(pc),a0 */ 0x20AF, 0x0008, /* move.l 4+4(a7),(a0) */ 0x41FA, 0xFEA0, /* lea.l numcalls(pc),a0 */ 0x4290, /* clr.l (a0) */ 0x6104, /* bsr.b put_trap */ 0x205F, /* movea.l (a7)+,a0 */ 0x4E75, /* rts */ /* set_iltrap = 17 WORDS */ 0x2F09, /* put_trap move.l a1,-(a7) */ 0x43FA, 0xFE96, /* lea.l oldtrap(pc),a1 */ 0x4A91, /* tst.l (a1) */ 0x6614, /* bne.b .trapped */ 0x2078, 0x0004, /* movea.l (4).w,a0 */ 0x2068, 0x0114, /* movea.l $114(a0),a0 */ 0x41E8, 0x0032, /* lea.l $32(a0),a0 */ 0x2290, /* move.l (a0),(a1) */ 0x43FA, 0xFE88, /* lea.l trapit(pc),a1 */ 0x2089, /* move.l a1,(a0) */ 0x225F, /* .trapped move.l (a7)+,a1 */ 0x4E75, /* rts */ /* put_trap = 17 WORDS */ /* set_iltrap + put_trap = 34 WORDS */ 0x2F08, /* set_ilnumber move.l a0,-(a7) */ 0x41FA, 0xFE6C, /* lea.l ilnumber(pc),a0 */ 0x20AF, 0x0008, /* move.l 4+4(a7),(a0) */ 0x205F, /* move.l (a7)+,a0 */ 0x4E75, /* rts */ /* set_ilnumber = 7 WORDS */ 0x2F08, /* clear_iltrap move.l a0,-(a7) */ 0x41FA, 0x005E, /* lea.l initenv(pc),a0 */ 0x4A90, /* tst.l (a0) */ 0x6606, /* bne.b .il_only */ 0x6100, 0x0028, /* bsr.w free_trap */ 0x6006, /* bra.b .done */ 0x41FA, 0xFE5C, /* il_only lea.l ilfunc(pc),a0 */ 0x4290, /* clr.l (a0) */ 0x205F, /* .done movea.l (a7)+,a0 */ 0x4E75, /* rts */ /* clear_iltrap = 13 WORDS */ 0x2F08, /* clear_init_trap move.l a0,-(a7) */ 0x41FA, 0xFE50, /* lea.l ilfunc(pc),a0 */ 0x4A90, /* tst.l (a0) */ 0x6606, /* bne.b .init_only */ 0x6100, 0x000E, /* bsr.w free_trap */ 0x6006, /* bra.b .done */ 0x41FA, 0x0036, /* .init_only lea.l initenv(pc),a0 */ 0x4290, /* clr.l (a0) */ 0x205F, /* .done move.l (a7)+,a0 */ 0x4E75, /* rts */ /* clear_init_trap = 13 WORDS */ 0x48E7, 0x00C0, /* free_trap movem.l a0-a1,-(a7) */ 0x41FA, 0xFE34, /* lea.l ilfunc(pc),a0 */ 0x4290, /* clr.l (a0) */ 0x41FA, 0x0022, /* lea.l initenv(pc),a0 */ 0x4290, /* clr.l (a0) */ 0x2078, 0x0004, /* movea.l (4).w,a0 */ 0x2068, 0x0114, /* movea.l $114(a0),a0 */ 0x41E8, 0x0032, /* lea.l 50(a0),a0 */ 0x43FA, 0xFE18, /* lea.l oldtrap(pc),a1 */ 0x4A91, /* tst.l (a1) */ 0x6704, /* beq.b .quit */ 0x2091, /* move.l (a1),(a0) */ 0x4291, /* clr.l (a1) */ 0x4CDF, 0x0300, /* .quit movem.l (a7)+,a0-a1 */ 0x4E75, /* rts */ /* free_trap = 23 WORDS */ /* The rest is not initialized, i.e. zero */ /* initenv ds.b sizeof_env */ /* inlineenv ds.b sizeof_env */ }; VOID NoError(VOID) { printf("\nNo Error...\n"); } VOID BusError(VOID) { printf("\nSorry, can't create exception 2.\n"); } #define NUMFUNCS 13 VOID (*func[NUMFUNCS])(VOID) = { (VOID (*)())NoError, (VOID (*)())NoError, (VOID (*)())BusError, (VOID (*)())&address_exc, (VOID (*)())&illegal_exc, (VOID (*)())&div0_exc, (VOID (*)())&chk_exc, (VOID (*)())&trapv_exc, (VOID (*)())&privelege_exc, (VOID (*)())&trace_exc, (VOID (*)())&A_Line_exc, (VOID (*)())&F_Line_exc, (VOID (*)())&trap1_exc, }; /* Trapit functions */ #define NUMTRAPFUNCS 9 VOID (*TrapFunc[NUMTRAPFUNCS])(...) = { (VOID (*)(struct TrapEnvironment *))MyTrap.restore, /* restore env */ (VOID (*)(struct TrapEnvironment))MyTrap.save_env, /* save env */ (VOID (*)(APTR))MyTrap.set_init_trap, /* set initial trap */ (VOID (*)(APTR))MyTrap.set_iltrap, /* set inline trap */ (VOID (*)(ULONG))MyTrap.set_ilnumber, /* set user trap number */ (VOID (*)(VOID))MyTrap.clear_iltrap, /* clear inline trap */ (VOID (*)(VOID))MyTrap.clear_init_trap, /* clear initial trap */ (VOID (*)(VOID))MyTrap.free_trap /* free the whole trap */ }; #define RESTORE_ENV(x) (*TrapFunc[0])(x) #define SAVE_ENV(x) (*TrapFunc[1])(x) #define SET_INIT_TRAP(x) (*TrapFunc[2])(x) #define SET_ILTRAP(x) (*TrapFunc[3])(x);\ if(MyTrap.numcalls==0){ #define ILTRAP }else{ #define END_ILTRAP } #define SET_TRAPNUM(x) (*TrapFunc[4])(x) #define RESET_ILTRAP(x) }SET_ILTRAP(x) #define CLEAR_ILTRAP() (*TrapFunc[5])() #define CLEAR_INIT_TRAP() (*TrapFunc[6])() #define FREE_TRAP() (*TrapFunc[7])() static struct TrapEnvironment TestEnv; VOID main(VOID) { int n; SET_INIT_TRAP(&ExitInitTrap); printf("WARNING: I have got A-Line Exception working on standard 68000 only.\n"); printf(" It gurus on my Derringer accelerated A2000HD (68030/68881).\n\n"); printf("Testing ILTRAP\n"); SET_ILTRAP(&InLineFunction); SAVE_ENV(&TestEnv); printf(" 0 No Error... 0\n"); printf(" 1 No Error... 1\n"); printf(" 2 Bus error 2 Can't create this one!\n"); printf(" 3 Address error 3\n"); printf(" 4 Illegal instruction 4\n"); printf(" 5 Divide by zero error 5\n"); printf(" 6 chk exception 6\n"); printf(" 7 trapv exception 7\n"); printf(" 8 Privelege violation 8\n"); printf(" 9 trace exception 9\n"); printf(" 10 1010 (A) emulation 10 (WARNING: possible Guru exception #3\n"); printf(" 11 1111 (F) emulation 11\n"); printf(" 33 Trap #1 ( = $21) 33\n"); printf(" 100 Restore Environment to before this...\n"); printf(" 101 Restore Environment from elsewhere...\n"); printf("\n WHICH: "); scanf("%ld",&n); if (n == 100) /* You can do this as many times as you like */ RESTORE_ENV(&TestEnv); if (n == 101) ElseWhere("We got here"); if (n==33) n = 12; else if (n==12) n = 33; SET_TRAPNUM(n<<2); if ((n>=0) && (n>\n"); END_ILTRAP printf("Now testing INIT_TRAP\n"); CLEAR_ILTRAP(); RESTORE_ENV(&TestEnv); printf("---- ALL DONE ---- (don't know how you got here!)\n"); ClearUp(); } /* Function called by SET_ILTRAP if a CPU exception occurs */ VOID InLineFunction(VOID) { printf("INLINE TRAP:\n"); printf("Clever me! I have trapped exception number %ld\n",MyTrap.trapnum); printf("The user number was %ld\n\n",MyTrap.ilnumber); } /* To test a restore from way off! */ VOID ElseWhere(char *s) { printf("ElseWhere: %s!\n",s); RESTORE_ENV(&TestEnv); } /* Free memory, close up everything and exit... */ VOID ClearUp(VOID) { FREE_TRAP(); printf("Press a key or WINDOWCLOSE gadget to quit"); fseek(stdin, 0, SEEK_END); getch(); exit(0); /* exit(0) will fix stack */ } /* Our Exception Code Exits To Here (Init_Trap) */ VOID ExitInitTrap(VOID) { printf("INITIAL TRAP\n"); printf("Clever me! I have trapped exception number %ld\n\n",MyTrap.trapnum); ClearUp(); } /* << END OF FILE >> */