/* $OpenBSD: proctime.c,v 1.4 2011/05/31 14:02:26 jasper Exp $	*/

/* Copyright (C) 1998-99 Martin Baulig
   This file is part of LibGTop 1.0.

   Contributed by Martin Baulig <martin@home-of-linux.org>, April 1998.

   LibGTop is free software; you can redistribute it and/or modify it
   under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License,
   or (at your option) any later version.

   LibGTop is distributed in the hope that it will be useful, but WITHOUT
   ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
   FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
   for more details.

   You should have received a copy of the GNU General Public License
   along with LibGTop; see the file COPYING. If not, write to the
   Free Software Foundation, Inc., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.
*/

#include <config.h>
#include <glibtop.h>
#include <glibtop/error.h>
#include <glibtop/proctime.h>

#include <glibtop_suid.h>

static const unsigned long _glibtop_sysdeps_proc_time =
(1L << GLIBTOP_PROC_TIME_RTIME) + (1L << GLIBTOP_PROC_TIME_FREQUENCY);

static const unsigned long _glibtop_sysdeps_proc_time_user =
(1L << GLIBTOP_PROC_TIME_UTIME) + (1L << GLIBTOP_PROC_TIME_STIME) +
(1L << GLIBTOP_PROC_TIME_CUTIME) + (1L << GLIBTOP_PROC_TIME_CSTIME) +
(1L << GLIBTOP_PROC_TIME_START_TIME);

#define tv2sec(tv)	(((guint64) tv.tv_sec * 1000000) + (guint64) tv.tv_usec)

static unsigned int clockrate;
static int mib [] = { CTL_KERN, KERN_CLOCKRATE };

/* Init function. */

void
_glibtop_init_proc_time_p (glibtop *server)
{
	struct clockinfo ci;
	size_t length;
	length = sizeof (ci);
	if (sysctl (mib, 2, &ci, &length, NULL, 0) == 0)
		clockrate = ci.hz;
	if (!clockrate)
		clockrate = 1; /* XXX avoid div by 0 later */

	server->sysdeps.proc_time = _glibtop_sysdeps_proc_time |
		_glibtop_sysdeps_proc_time_user;
}

/* Taken from /usr/src/sys/kern/kern_resource.c */

/*
 * Transform the running time and tick information in proc p into user,
 * system, and interrupt time usage.
 */

static void
calcru(p, up, sp, ip)
     struct proc *p;
     struct timeval *up;
     struct timeval *sp;
     struct timeval *ip;
{
	quad_t totusec;
	u_quad_t u, st, ut, it, tot;
        long sec, usec;
        struct timeval tv;

	st = p->p_sticks;
	ut = p->p_uticks;
	it = p->p_iticks;

	tot = st + ut + it;
	if (tot == 0) {
		st = 1;
		tot = 1;
	}

	sec = p->p_rtime.tv_sec;
	usec = p->p_rtime.tv_usec;

	totusec = (quad_t)sec * 1000000 + usec;

	if (totusec < 0) {
		/* XXX no %qd in kernel.  Truncate. */
		fprintf (stderr, "calcru: negative time: %ld usec\n",
			 (long)totusec);
		totusec = 0;
	}


	u = totusec;
	st = (u * st) / tot;
	sp->tv_sec = st / 1000000;
	sp->tv_usec = st % 1000000;
	ut = (u * ut) / tot;
	up->tv_sec = ut / 1000000;
	up->tv_usec = ut % 1000000;
	if (ip != NULL) {
		it = (u * it) / tot;
		ip->tv_sec = it / 1000000;
		ip->tv_usec = it % 1000000;
	}
}

/* Provides detailed information about a process. */

void
glibtop_get_proc_time_p (glibtop *server, glibtop_proc_time *buf,
			 pid_t pid)
{
	struct kinfo_proc2 *pinfo;
	int count;

	glibtop_init_p (server, (1L << GLIBTOP_SYSDEPS_PROC_TIME), 0);

	memset (buf, 0, sizeof (glibtop_proc_time));

	/* It does not work for the swapper task. */
	if (pid == 0) return;


	/* Get the process information */
	pinfo = kvm_getproc2 (server->machine.kd, KERN_PROC_PID, pid,
			      sizeof (*pinfo), &count);
	if ((pinfo == NULL) || (count != 1)) {
		glibtop_warn_io_r (server, "kvm_getprocs (%d)", pid);
		return;
	}

	buf->rtime = pinfo[0].p_rtime_sec * clockrate 
		+ pinfo[0].p_rtime_usec  * clockrate / 1000000;
	buf->frequency = clockrate;

	buf->flags = _glibtop_sysdeps_proc_time;

	buf->utime = pinfo[0].p_uutime_sec * 1000000
		+ pinfo[0].p_uutime_usec;
	buf->stime = pinfo[0].p_ustime_sec * 1000000
		+ pinfo[0].p_ustime_usec;
	buf->cutime = pinfo[0].p_uctime_sec * 1000000
		+ pinfo[0].p_uctime_usec; /* XXX is u+s */
	buf->cstime = 0; /* XXX */
	buf->start_time = pinfo[0].p_ustart_sec;

	buf->flags |= _glibtop_sysdeps_proc_time_user;
}