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/*
* Copyright (c) 1992, 1993, 1996
* Berkeley Software Design, Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Berkeley Software
* Design, Inc.
*
* THIS SOFTWARE IS PROVIDED BY Berkeley Software Design, Inc. ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL Berkeley Software Design, Inc. BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* BSDI trace.c,v 2.2 1996/04/08 19:33:07 bostic Exp
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "doscmd.h"
#include "trap.h"
int tmode = 0;
static u_short *saddr;
static u_char *iaddr, ibyte;
/* locals */
static void printtrace(regcontext_t *REGS, char *buf);
static __inline void showstate(long, long, char);
/*
* Before exiting to VM86 mode:
* 1) Always set the trap flag.
* 2) If this is a POPF or IRET instruction, set the trap flag in the saved
* flag state on the stack.
* On entering from VM86 mode:
* 1) Restore the trap flag from our saved flag state.
* 2) If we just finished a POPF or IRET instruction, patch the saved flag
* state on the stack.
*/
int tracetype;
int
resettrace(regcontext_t *REGS)
{
if ((R_EFLAGS & PSL_VM) == 0) /* invalid unless handling a vm86 process */
return (0);
/* XXX */ return 1;
switch (tracetype) {
case 1:
R_EFLAGS &= ~PSL_T;
tracetype = 0;
return (1);
case 2:
if ((u_char *)MAKEPTR(R_CS, R_IP - 1) == iaddr)
R_IP --;
*iaddr = ibyte;
tracetype = 0;
return (1);
case 3:
case 4:
R_EFLAGS &= ~PSL_T;
*saddr &= ~PSL_T;
tracetype = 0;
return (1);
}
return (0);
}
void
tracetrap(regcontext_t *REGS)
{
u_char *addr;
int n;
char buf[100];
if ((R_EFLAGS & PSL_VM) == 0)
return;
addr = (u_char *)MAKEPTR(R_CS, R_IP);
n = i386dis(R_CS, R_IP, addr, buf, 0);
printtrace(REGS, buf);
/* XXX */
R_EFLAGS |= PSL_T;
return;
/* XXX */
switch (addr[0]) {
case REPNZ:
case REPZ:
tracetype = 2;
iaddr = (u_char *)MAKEPTR(R_CS, R_IP + n);
break;
case PUSHF:
tracetype = 4;
saddr = (u_short *)MAKEPTR(R_SS, R_SP - 2);
break;
case POPF:
tracetype = 3;
saddr = (u_short *)MAKEPTR(R_SS, R_SP + 0);
break;
case IRET:
tracetype = 3;
saddr = (u_short *)MAKEPTR(R_SS, R_SP + 4);
#if 0
printf("IRET: %04x %04x %04x\n",
((u_short *)MAKEPTR(R_SS, R_SP))[0],
((u_short *)MAKEPTR(R_SS, R_SP))[1],
((u_short *)MAKEPTR(R_SS, R_SP))[2]);
#endif
break;
case OPSIZ:
switch (addr[1]) {
case PUSHF:
tracetype = 4;
saddr = (u_short *)MAKEPTR(R_SS, R_SP - 4);
break;
case POPF:
tracetype = 3;
saddr = (u_short *)MAKEPTR(R_SS, R_SP + 0);
break;
case IRET:
tracetype = 3;
saddr = (u_short *)MAKEPTR(R_SS, R_SP + 8);
break;
default:
tracetype = 1;
break;
}
default:
tracetype = 1;
break;
}
switch (tracetype) {
case 1:
case 4:
if (R_EFLAGS & PSL_T)
tracetype = 0;
else
R_EFLAGS |= PSL_T;
break;
case 2:
if (*iaddr == TRACETRAP)
tracetype = 0;
else {
ibyte = *iaddr;
*iaddr = TRACETRAP;
}
break;
case 3:
R_EFLAGS |= PSL_T;
if (*saddr & PSL_T)
tracetype = 0;
else
*saddr |= PSL_T;
break;
}
}
static __inline void
showstate(long flags, long flag, char f)
{
putc((flags & flag) ? f : ' ', debugf);
}
static void
printtrace(regcontext_t *REGS, char *buf)
{
static int first = 1;
#if BIG_DEBUG
u_char *addr = (u_char *)MAKEPTR(R_CS, R_IP);
#endif
if (first) {
fprintf(debugf, "%4s:%4s "
#if BIG_DEBUG
".. .. .. .. .. .. "
#endif
"%-30s "
"%4s %4s %4s %4s %4s %4s %4s %4s %4s %4s %4s\n",
"CS", "IP", "instruction",
"AX", "BX", "CX", "DX",
"DI", "SI", "SP", "BP",
"SS", "DS", "ES");
first = 0;
}
fprintf(debugf, "%04x:%04x "
#if BIG_DEBUG
"%02x %02x %02x %02x %02x %02x "
#endif
"%-30s "
"%04x %04x %04x %04x %04x %04x %04x %04x %04x %04x %04x ",
R_CS, R_IP,
#if BIG_DEBUG
addr[0], addr[1], addr[2], addr[3], addr[4], addr[5],
#endif
buf,
R_AX, R_BX, R_CX, R_DX, R_DI, R_SI, R_SP, R_BP, R_SS, R_DS, R_ES);
#if 0
fprintf(debugf, "%04x %04x %04x %04x ",
((u_short *)VECPTR(0x0D760FCA-14))[0],
((u_short *)VECPTR(0x0D760FCA-14))[1],
((u_short *)VECPTR(0x0D760F7A+8))[0],
((u_short *)VECPTR(0x0D760F7A+8))[1]);
#endif
showstate(R_EFLAGS, PSL_C, 'C');
showstate(R_EFLAGS, PSL_PF, 'P');
showstate(R_EFLAGS, PSL_AF, 'c');
showstate(R_EFLAGS, PSL_Z, 'Z');
showstate(R_EFLAGS, PSL_N, 'N');
showstate(R_EFLAGS, PSL_T, 'T');
showstate(R_EFLAGS, PSL_I, 'I');
showstate(R_EFLAGS, PSL_D, 'D');
showstate(R_EFLAGS, PSL_V, 'V');
showstate(R_EFLAGS, PSL_NT, 'n');
showstate(R_EFLAGS, PSL_RF, 'r');
showstate(R_EFLAGS, PSL_VM, 'v');
showstate(R_EFLAGS, PSL_AC, 'a');
showstate(R_EFLAGS, PSL_VIF, 'i');
showstate(R_EFLAGS, PSL_VIP, 'p');
putc('\n', debugf);
}
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