minix/minix/net/inet/clock.c
David van Moolenbroek d91f738bd8 Kernel: export clock information on kernel page
Please note that this information is for use by system services only!
The clock facility is not ready to be used directly by userland, and
thus, this kernel page extension is NOT part of the userland ABI.

For service programmers' convenience, change the prototype of the
getticks(3) to return the uptime clock value directly, since the call
can no longer fail.

Correct the sys_times(2) reply message to use the right field type
for the boot time.

Restructure the kernel internals a bit so as to have all the clock
stuff closer together.

Change-Id: Ifc050b7bd253aecbe46e3bd7d7cc75bd86e45555
2015-09-23 12:00:46 +00:00

191 lines
3.2 KiB
C

/*
clock.c
Copyright 1995 Philip Homburg
*/
#include "inet.h"
#include "proto.h"
#include "generic/assert.h"
#include "generic/buf.h"
#include "generic/clock.h"
THIS_FILE
int clck_call_expire;
static clock_t curr_time;
static clock_t prev_time;
static minix_timer_t *timer_chain;
static time_t next_timeout;
static void clck_fast_release(minix_timer_t *timer);
static void set_timer(void);
void clck_init()
{
clck_call_expire= 0;
curr_time= 0;
prev_time= 0;
next_timeout= 0;
timer_chain= 0;
}
time_t get_time()
{
if (!curr_time)
{
curr_time = getticks();
assert(curr_time >= prev_time); /* XXX */
}
return curr_time;
}
void set_time (tim)
clock_t tim;
{
if (!curr_time && tim >= prev_time)
{
/* Some code assumes that no time elapses while it is
* running.
*/
curr_time= tim;
}
else if (!curr_time)
{
DBLOCK(0x20, printf("set_time: new time %lu < prev_time %lu\n",
tim, prev_time));
}
}
void reset_time()
{
prev_time= curr_time;
curr_time= 0;
}
void clck_timer(timer, timeout, func, fd)
minix_timer_t *timer;
time_t timeout;
timer_func_t func;
int fd;
{
minix_timer_t *timer_index;
if (timer->tim_active)
clck_fast_release(timer);
assert(!timer->tim_active);
timer->tim_next= 0;
timer->tim_func= func;
timer->tim_ref= fd;
timer->tim_time= timeout;
timer->tim_active= 1;
if (!timer_chain)
timer_chain= timer;
else if (timeout < timer_chain->tim_time)
{
timer->tim_next= timer_chain;
timer_chain= timer;
}
else
{
timer_index= timer_chain;
while (timer_index->tim_next &&
timer_index->tim_next->tim_time < timeout)
timer_index= timer_index->tim_next;
timer->tim_next= timer_index->tim_next;
timer_index->tim_next= timer;
}
if (next_timeout == 0 || timer_chain->tim_time < next_timeout)
set_timer();
}
void clck_tick (mess)
message *mess;
{
next_timeout= 0;
set_timer();
}
static void clck_fast_release (timer)
minix_timer_t *timer;
{
minix_timer_t *timer_index;
if (!timer->tim_active)
return;
if (timer == timer_chain)
timer_chain= timer_chain->tim_next;
else
{
timer_index= timer_chain;
while (timer_index && timer_index->tim_next != timer)
timer_index= timer_index->tim_next;
assert(timer_index);
timer_index->tim_next= timer->tim_next;
}
timer->tim_active= 0;
}
static void set_timer()
{
time_t new_time;
time_t now;
if (!timer_chain)
return;
now= get_time();
new_time= timer_chain->tim_time;
if (new_time <= now)
{
clck_call_expire= 1;
return;
}
if (next_timeout == 0 || new_time < next_timeout)
{
next_timeout= new_time;
new_time -= now;
if (sys_setalarm(new_time, 0) != OK)
ip_panic(("can't set timer"));
}
}
void clck_untimer (timer)
minix_timer_t *timer;
{
clck_fast_release (timer);
set_timer();
}
void clck_expire_timers()
{
time_t now;
minix_timer_t *timer_index;
clck_call_expire= 0;
if (timer_chain == NULL)
return;
now= get_time();
while (timer_chain && timer_chain->tim_time<=now)
{
assert(timer_chain->tim_active);
timer_chain->tim_active= 0;
timer_index= timer_chain;
timer_chain= timer_chain->tim_next;
(*timer_index->tim_func)(timer_index->tim_ref, timer_index);
}
set_timer();
}
/*
* $PchId: clock.c,v 1.10 2005/06/28 14:23:40 philip Exp $
*/