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[unix-history] / usr / src / sys / kern / kern_acct.c

/*      kern_acct.c     6.2     84/07/08        */

#include "../h/param.h"
#include "../h/systm.h"
#include "../h/dir.h"
#include "../h/user.h"
#include "../h/inode.h"
#include "../h/fs.h"
#include "../h/kernel.h"
#include "../h/acct.h"
#include "../h/uio.h"

/*
* SHOULD REPLACE THIS WITH A DRIVER THAT CAN BE READ TO SIMPLIFY.
*/
struct  inode *acctp;
struct  inode *savacctp;

/*
* Perform process accounting functions.
*/
sysacct()
{
       register struct inode *ip;
       register struct a {
               char    *fname;
       } *uap = (struct a *)u.u_ap;
       register struct nameidata *ndp = &u.u_nd;

       if (suser()) {
               if (savacctp) {
                       acctp = savacctp;
                       savacctp = NULL;
               }
               if (uap->fname==NULL) {
                       if (ip = acctp) {
                               irele(ip);
                               acctp = NULL;
                       }
                       return;
               }
               ndp->ni_nameiop = LOOKUP | FOLLOW;
               ndp->ni_segflg = UIO_USERSPACE;
               ndp->ni_dirp = uap->fname;
               ip = namei(ndp);
               if(ip == NULL)
                       return;
               if((ip->i_mode & IFMT) != IFREG) {
                       u.u_error = EACCES;
                       iput(ip);
                       return;
               }
               if (acctp && (acctp->i_number != ip->i_number ||
                   acctp->i_dev != ip->i_dev))
                       irele(acctp);
               acctp = ip;
               iunlock(ip);
       }
}

int     acctsuspend = 2;        /* stop accounting when < 2% free space left */
int     acctresume = 4;         /* resume when free space risen to > 4% */

struct  acct acctbuf;
/*
* On exit, write a record on the accounting file.
*/
acct()
{
       register int i;
       register struct inode *ip;
       register struct fs *fs;
       off_t siz;
       register struct acct *ap = &acctbuf;

       if (savacctp) {
               fs = savacctp->i_fs;
               if (freespace(fs, fs->fs_minfree + acctresume) > 0) {
                       acctp = savacctp;
                       savacctp = NULL;
                       printf("Accounting resumed\n");
               }
       }
       if ((ip = acctp) == NULL)
               return;
       fs = acctp->i_fs;
       if (freespace(fs, fs->fs_minfree + acctsuspend) <= 0) {
               savacctp = acctp;
               acctp = NULL;
               printf("Accounting suspended\n");
               return;
       }
       ilock(ip);
       for (i = 0; i < sizeof (ap->ac_comm); i++)
               ap->ac_comm[i] = u.u_comm[i];
       ap->ac_utime = compress((long)u.u_ru.ru_utime.tv_sec);
       ap->ac_stime = compress((long)u.u_ru.ru_stime.tv_sec);
       ap->ac_etime = compress((long)time.tv_sec - u.u_start);
       ap->ac_btime = u.u_start;
       ap->ac_uid = u.u_ruid;
       ap->ac_gid = u.u_rgid;
       ap->ac_mem = 0;
       if (i = u.u_ru.ru_utime.tv_sec + u.u_ru.ru_stime.tv_sec)
               ap->ac_mem =
                   (u.u_ru.ru_ixrss + u.u_ru.ru_idrss + u.u_ru.ru_isrss) / i;
       ap->ac_io = compress((long)(u.u_ru.ru_inblock + u.u_ru.ru_oublock));
       if (u.u_ttyp)
               ap->ac_tty = u.u_ttyd;
       else
               ap->ac_tty = NODEV;
       ap->ac_flag = u.u_acflag;
       siz = ip->i_size;
       u.u_error = 0;                          /* XXX */
       u.u_error =
           rdwri(UIO_WRITE, ip, (caddr_t)ap, sizeof (acctbuf), siz,
               1, (int *)0);
       if (u.u_error)
               itrunc(ip, (u_long)siz);
       iunlock(ip);
}

/*
* Produce a pseudo-floating point representation
* with 3 bits base-8 exponent, 13 bits fraction.
*/
compress(t)
       register long t;
{
       register exp = 0, round = 0;

       while (t >= 8192) {
               exp++;
               round = t&04;
               t >>= 3;
       }
       if (round) {
               t++;
               if (t >= 8192) {
                       t >>= 3;
                       exp++;
               }
       }
       return ((exp<<13) + t);
}