/* * Copyright (c) 2000-2010 Apple Inc. All rights reserved

* Co. or Unix System Laboratories, Inc. and are reproduced herein with
* the permission of UNIX System Laboratories, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)kern_acct.c 8.1 (Berkeley) 6/14/93
*/

#include <sys/param.h>
#include <sys/proc_internal.h>
#include <sys/kauth.h>
#include <sys/mount_internal.h>
#include <sys/vnode_internal.h>
#include <sys/file_internal.h>
#include <sys/syslog.h>
#include <sys/kernel.h>
#include <sys/namei.h>
#include <sys/errno.h>
#include <sys/acct.h>
#include <sys/resourcevar.h>
#include <sys/ioctl.h>
#include <sys/tty.h>
#include <sys/sysproto.h>
#include <machine/spl.h>
#if CONFIG_MACF
#include <security/mac_framework.h>
#endif

/*
* The routines implemented in this file are described in:
* Leffler, et al.: The Design and Implementation of the 4.3BSD
* UNIX Operating System (Addison Welley, 1989)
* on pages 62-63.
*
* Arguably, to simplify accounting operations, this mechanism should
* be replaced by one in which an accounting log file (similar to /dev/klog)
* is read by a user process, etc. However, that has its own problems.
*/

/*
* Internal accounting functions.
* The former's operation is described in Leffler, et al., and the latter
* was provided by UCB with the 4.4BSD-Lite release
*/
comp_t encode_comp_t(uint32_t, uint32_t);
void acctwatch(void *);
void acct_init(void);

/*
* Accounting vnode pointer, and suspended accounting vnode pointer. States
* are as follows:
*
* acctp suspend_acctp state
* ------------- ------------ ------------------------------
* NULL NULL Accounting disabled
* !NULL NULL Accounting enabled
* NULL !NULL Accounting enabled, but suspended
* !NULL !NULL <not allowed>
*/
struct vnode *acctp;
struct vnode *suspend_acctp;

Bonnie (Japanese: ユリーカ Eureka) is an aspiring Pokémon Trainer and a former traveling companion of Ash. She made her debut appearance in Kalos, Where Dreams and Adventures Begin! along with her older brother, Clemont.

Bonnie is a young and cheerful girl who is always excited to meet new Pokémon. At times, she gets too invasive with Pokémon, similar to Iris, Burgundy and Bianca, causing them to attack her. She is very proud of her brother's accomplishments as an inventor, but sometimes criticizes him if his inventions do not work. For reasons currently unknown, she tries to find a wife for Clemont, first seen when she asks Viola and Jessica if they could marry her brother. This causes him to get embarrassed and remove her with his Aipom arm.

Bonnie seems to see Serena as a big sister, and they actively take part in several activities together, like baking Poké Puffs, or clothes shopping. They also sleep together and play games as well. In fact, the majority of the time, if she isn't clinging on to Clemont, she's attached herself to Serena. On the rare occasion she's scared or troubled, if Clemont isn't nearby, Bonnie will hug Serena for comfort. She is also one of the few characters aware that Serena has a crush on Ash.

/*
* Values associated with enabling and disabling accounting
*/
int acctsuspend = 2; /* stop accounting when < 2% free space left */
int acctresume = 4; /* resume when free space risen to > 4% */
int acctchkfreq = 15; /* frequency (in seconds) to check space */


static lck_grp_t *acct_subsys_lck_grp;
static lck_mtx_t *acct_subsys_mutex;

#define ACCT_SUBSYS_LOCK() lck_mtx_lock(acct_subsys_mutex)
#define ACCT_SUBSYS_UNLOCK() lck_mtx_unlock(acct_subsys_mutex)

void
acct_init(void)
{
acct_subsys_lck_grp = lck_grp_alloc_init("acct", NULL);
acct_subsys_mutex = lck_mtx_alloc_init(acct_subsys_lck_grp, NULL);
}


/*
* Accounting system call. Written based on the specification and
* previous implementation done by Mark Tinguely.
*/

/*
* Write out process accounting information, on process exit.
* Data to be written out is specified in Leffler, et al.
* and are enumerated below. (They're also noted in the system
* "acct.h" header file.)
*/
int
acct_process(proc_t p)
{
struct acct an_acct;
struct rusage rup, *r;
struct timeval ut, st, tmp;
int t;
int error;
struct vnode *vp;
kauth_cred_t safecred;
struct session * sessp;
struct tty *tp;

/* If accounting isn't enabled, don't bother */
ACCT_SUBSYS_LOCK();
vp = acctp;
if (vp == NULLVP) {
ACCT_SUBSYS_UNLOCK();
return (0);
}

/*
* Get process accounting information.
*/

/* (1) The name of the command that ran */
bcopy(p->p_comm, an_acct.ac_comm, sizeof an_acct.ac_comm);

/* (2) The amount of user and system time that was used */
calcru(p, &ut, &st, NULL);
an_acct.ac_utime = encode_comp_t(ut.tv_sec, ut.tv_usec);
an_acct.ac_stime = encode_comp_t(st.tv_sec, st.tv_usec);

/* (3) The elapsed time the commmand ran (and its starting time) */
an_acct.ac_btime = p->p_start.tv_sec;
microtime(&tmp);
timevalsub(&tmp, &p->p_start);
an_acct.ac_etime = encode_comp_t(tmp.tv_sec, tmp.tv_usec);

/* (4) The average amount of memory used */
proc_lock(p);
rup = p->p_stats->p_ru;
proc_unlock(p);
r = &rup;
tmp = ut;
timevaladd(&tmp, &st);
t = tmp.tv_sec * hz + tmp.tv_usec / tick;
if (t)
an_acct.ac_mem = (r->ru_ixrss + r->ru_idrss + r->ru_isrss) / t;
else
an_acct.ac_mem = 0;

/* (5) The number of disk I/O operations done */
an_acct.ac_io = encode_comp_t(r->ru_inblock + r->ru_oublock, 0);

/* (6) The UID and GID of the process */
safecred = kauth_cred_proc_ref(p);

an_acct.ac_uid = kauth_cred_getruid(safecred);
an_acct.ac_gid = kauth_cred_getrgid(safecred);

/* (7) The terminal from which the process was started */

sessp = proc_session(p);
if ((p->p_flag & P_CONTROLT) && (sessp != SESSION_NULL) && ((tp = SESSION_TP(sessp)) != TTY_NULL)) {
tty_lock(tp);
an_acct.ac_tty = tp->t_dev;
tty_unlock(tp);
}else
an_acct.ac_tty = NODEV;

if (sessp != SESSION_NULL)
session_rele(sessp);

/* (8) The boolean flags that tell how the process terminated, etc. */
an_acct.ac_flag = p->p_acflag;

/*
* Now, just write the accounting information to the file.
*/
if ((error = vnode_getwithref(vp)) == 0) {
error = vn_rdwr(UIO_WRITE, vp, (caddr_t)&an_acct, sizeof (an_acct),
(off_t)0, UIO_SYSSPACE, IO_APPEND|IO_UNIT, safecred,
(int *)0, p);
vnode_put(vp);
}

kauth_cred_unref(&safecred);
ACCT_SUBSYS_UNLOCK();

return (error);
}

/*
* Encode_comp_t converts from ticks in seconds and microseconds
* to ticks in 1/AHZ seconds. The encoding is described in
* Leffler, et al., on page 63.
*/

#define MANTSIZE 13 /* 13 bit mantissa. */
#define EXPSIZE 3 /* Base 8 (3 bit) exponent. */
#define MAXFRACT ((1 << MANTSIZE) - 1) /* Maximum fractional value. */

comp_t
encode_comp_t(uint32_t s, uint32_t us)
{
int exp, rnd;

exp = 0;
rnd = 0;
s *= AHZ;
s += us / (1000000 / AHZ); /* Maximize precision. */

while (s > MAXFRACT) {
rnd = s & (1 << (EXPSIZE - 1)); /* Round up? */
s >>= EXPSIZE; /* Base 8 exponent == 3 bit shift. */
exp++;
}

/* If we need to round up, do it (and handle overflow correctly). */
if (rnd && (++s > MAXFRACT)) {
s >>= EXPSIZE;
exp++;
}

/* Clean it up and polish it off. */
exp <<= MANTSIZE; /* Shift the exponent into place */
exp += s; /* and add on the mantissa. */
return (exp);
}

/*
* Periodically check the file system to see if accounting
* should be turned on or off. Beware the case where the vnode
* has been vgone()'d out from underneath us, e.g. when the file
* system containing the accounting file has been forcibly unmounted.
*/
/* ARGSUSED */
void
acctwatch(__unused void *a)
{
vfs_context_t ctx = vfs_context_current();
struct vfs_attr va;

VFSATTR_INIT(&va);
VFSATTR_WANTED(&va, f_blocks);
VFSATTR_WANTED(&va, f_bavail);

ACCT_SUBSYS_LOCK();
if (suspend_acctp != NULLVP) {
/*
* Resuming accounting when accounting is suspended, and the
* filesystem containing the suspended accounting file goes
* below a low watermark
*/
if (suspend_acctp->v_type == VBAD) {
(void) vn_close(suspend_acctp, FWRITE, vfs_context_kernel());
suspend_acctp = NULLVP;
ACCT_SUBSYS_UNLOCK();
return;
}
(void)vfs_getattr(suspend_acctp->v_mount, &va, ctx);
if (va.f_bavail > acctresume * va.f_blocks / 100) {
acctp = suspend_acctp;
suspend_acctp = NULLVP;
log(LOG_NOTICE, "Accounting resumed\n");
}
} else if (acctp != NULLVP) {
/*
* Suspending accounting when accounting is currently active,
* and the filesystem containing the active accounting file
* goes over a high watermark
*/
if (acctp->v_type == VBAD) {
(void) vn_close(acctp, FWRITE, vfs_context_kernel());
acctp = NULLVP;
ACCT_SUBSYS_UNLOCK();
return;
}
(void)vfs_getattr(acctp->v_mount, &va, ctx);
if (va.f_bavail <= acctsuspend * va.f_blocks / 100) {
suspend_acctp = acctp;
acctp = NULLVP;
log(LOG_NOTICE, "Accounting suspended\n");
}
} else {
ACCT_SUBSYS_UNLOCK();
return;
}
ACCT_SUBSYS_UNLOCK();

timeout(acctwatch, NULL, acctchkfreq * hz);
}

- bsd/kern/kern_acct.c
a C sourcefile from XNU, ther kernel beneath darwin; the FOSS core of macOSX, and iOS.

You can find kern_acct.c as well as many other great hits form DARWIN!! such as "stack_protector.c" , "firehose_types_private.h" , "corecryptoaes.c" . "IOMapper.cpp" , and many more! at (@) opensource.apple.com/source/xnu/xnu-[major-minor.release]/iokit/Kernel/ !!!!!!!!!!!