freebsd-dev/usr.bin/doscmd/timer.c
2001-12-02 13:48:40 +00:00

69 lines
1.5 KiB
C

/*
** No copyright?!
**
** $FreeBSD$
*/
#include "doscmd.h"
static void
int08(regcontext_t *REGS __unused)
{
*(u_long *)&BIOSDATA[0x6c] += 1; /* ticks since midnight */
while (*(u_long *)&BIOSDATA[0x6c] >= 24*60*6*182) {
*(u_long *)&BIOSDATA[0x6c] -= 24*60*6*182;
BIOSDATA[0x70]++; /* # times past mn */
}
/* What is the real BIOS' sequence? */
send_eoi();
softint(0x1c);
}
static void
int1c(regcontext_t *REGS __unused)
{
}
unsigned char timer;
static u_char
inb_timer(int port __unused)
{
return (--timer);
}
void
timer_init(void)
{
u_long vec;
struct itimerval itv;
struct timeval tv;
time_t tv_sec;
struct timezone tz;
struct tm tm;
vec = insert_hardint_trampoline();
ivec[0x08] = vec;
register_callback(vec, int08, "int 08");
vec = insert_softint_trampoline();
ivec[0x1c] = vec;
register_callback(vec, int1c, "int 1c");
define_input_port_handler(0x42, inb_timer);
define_input_port_handler(0x40, inb_timer);
/* Initialize time counter BIOS variable. */
gettimeofday(&tv, &tz);
tv_sec = tv.tv_sec;
tm = *localtime(&tv_sec);
*(u_long *)&BIOSDATA[0x6c] =
(((tm.tm_hour * 60 + tm.tm_min) * 60) + tm.tm_sec) * 182 / 10;
itv.it_interval.tv_sec = 0;
itv.it_interval.tv_usec = 54925; /* 1193182/65536 times per second */
itv.it_value.tv_sec = 0;
itv.it_value.tv_usec = 54925; /* 1193182/65536 times per second */
if (! timer_disable)
setitimer(ITIMER_REAL, &itv, 0);
}