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/*
** No copyright?!
**
** $Id: int.c,v 1.4 1997/03/18 02:36:56 msmith Exp $
*/
#include "doscmd.h"
/*
** Cause a software interrupt to happen immediately after we
** return to vm86 mode
*/
void
softint(int intnum)
{
regcontext_t *REGS = saved_regcontext;
u_long vec = ivec[intnum];
/*
** if we're dead, or there's no vector or the saved registers are
** invalid
*/
if (dead || !saved_valid || vec == 0)
return;
/*
** if the vector points into the BIOS, or the handler at the other
** end is just an IRET, don't bother.
*/
if ((vec >> 16) == 0xf000 || *(u_char *)VECPTR(vec) == 0xcf)
return;
#if 0
/*
* software interrupts are always taken
*/
if ((R_EFLAGS & PSL_VIF) == 0) {
delay_interrupt(intnum, softint);
return;
}
#endif
debug(D_TRAPS|intnum, "Int%x [%04x:%04x]\n",
intnum, vec >> 16, vec & 0xffff);
N_PUSH((R_FLAGS & ~PSL_I) | (R_EFLAGS & PSL_VIF ? PSL_I : 0), REGS);
N_PUSH(R_CS, REGS);
N_PUSH(R_IP, REGS);
#if 1
R_EFLAGS &= ~PSL_VIF; /* XXX disable interrupts? */
#else
R_EFLAGS |= PSL_VIF;
#endif
N_PUTVEC(R_CS, R_IP, vec);
}
/*
** Cause a hardware interrupt to happen immediately after
** we return to vm86 mode
*/
void
hardint(int intnum)
{
regcontext_t *REGS = saved_regcontext;
u_long vec = ivec[intnum];
/*
* XXXXX
* We should simulate the IRQ mask in the PIC.
*/
/*
** if we're dead, or there's no vector, or the saved registers
** are invalid
*/
if (dead || !saved_valid || vec == 0)
return;
/*
** if the vector points into the BIOS, or the handler at the
** other end is just an IRET, don't bother
*/
if ((vec >> 16) == 0xf000 || *(u_char *)VECPTR(vec) == 0xcf)
return;
if ((R_EFLAGS & PSL_VIF) == 0) {
delay_interrupt(intnum, hardint);
return;
}
debug(D_TRAPS|intnum, "Int%x [%04x:%04x]\n",
intnum, vec >> 16, vec & 0xffff);
N_PUSH((R_FLAGS & ~PSL_I) | (R_EFLAGS & PSL_VIF ? PSL_I : 0), REGS);
N_PUSH(R_CS, REGS);
N_PUSH(R_IP, REGS);
#if 1
R_EFLAGS &= ~PSL_VIF; /* XXX disable interrupts */
#else
R_EFLAGS |= PSL_VIF;
#endif
N_PUTVEC(R_CS, R_IP, vec);
}
typedef void (*foo_t)(int);
void
resume_interrupt(void)
{
int i;
regcontext_t *REGS = saved_regcontext;
n_pending--;
if (n_pending == 0)
R_EFLAGS &= ~PSL_VIP;
for (i = 0; i < 256; i++) {
if (pending[i]) {
((foo_t)(pending[i]))(i);
pending[i] = 0;
break;
}
}
}
void
delay_interrupt(int intnum, void (*func)(int))
{
regcontext_t *REGS = saved_regcontext;
#if 0
printf("DELAY [%x/%d]\n", intnum, n_pending);
#endif
if (pending[intnum] == 0) {
pending[intnum] = (u_long)func;
n_pending++;
}
R_EFLAGS |= PSL_VIP;
}
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