syn68k/runtime/dosinterrupts.c

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2008-09-26 14:25:10 +00:00
#ifdef MSDOS
#include "syn68k_private.h"
#ifndef SYNCHRONOUS_INTERRUPTS
int
dos_block_interrupts ()
{
unsigned long iflag;
asm ("pushfl\n\t" /* We save the old eflags, which has interrupt mask bit. */
"popl %0\n\t"
"shrl $9,%0\n\t"
"andl $1,%0\n\t"
"jz 1f\n\t" /* Avoid CLI overhead under DPMI. */
"cli\n"
"1:"
: "=r" (iflag)
: : "cc");
return iflag;
}
void
dos_restore_interrupts (int onoff)
{
unsigned long current_iflag;
asm ("pushfl\n\t" /* We save the old eflags, which has interrupt mask bit. */
"popl %0\n\t"
"shrl $9,%0\n\t"
"andl $1,%0"
: "=r" (current_iflag)
: : "cc");
if (onoff != current_iflag)
{
/* Only execute these when necessary, to avoid DPMI overhead. */
if (onoff)
asm ("sti");
else
asm ("cli");
}
}
#endif /* !SYNCHRONOUS_INTERRUPTS */
#endif /* MSDOS */