SRI-NOSC/ken/sys2.c
#
#include "param.h"
#include "systm.h"
#include "user.h"
#include "proc.h"
#include "reg.h"
#include "file.h"
#include "inode.h"
#ifdef NETSYS
#include "conf.h"
#endif NETSYS
/*
* read system call
*/
read()
{
rdwr(FREAD);
}
/*
* write system call
*/
write()
{
rdwr(FWRITE);
}
/*
* common code for read and write calls:
* check permissions, set base, count, and offset,
* and switch out to readi, writei, or pipe code.
*/
rdwr(mode)
{
register *fp, m;
m = mode;
fp = getf(u.u_ar0[R0]);
if(fp == NULL)
return;
if((fp->f_flag&m) == 0) {
u.u_error = EBADF;
return;
}
u.u_base = u.u_arg[0];
u.u_count = u.u_arg[1];
u.u_segflg = 0;
#ifdef NETSYS
if( fp->f_flag & FNET )
{
if( m == FREAD )
netread( fp->f_netnode[ f_rdnode ] );
else
netwrite( fp->f_netnode[ f_wrtnode ]);
}
else
#endif NETSYS
if(fp->f_flag&FPIPE) {
if(m==FREAD)
readp(fp); else
writep(fp);
} else {
u.u_offset[1] = fp->f_offset[1];
u.u_offset[0] = fp->f_offset[0];
if(m==FREAD)
readi(fp->f_inode); else
writei(fp->f_inode);
dpadd(fp->f_offset, u.u_arg[1]-u.u_count);
}
u.u_ar0[R0] = u.u_arg[1]-u.u_count;
}
/*
* open system call
*/
open()
{
register *ip;
extern uchar;
ip = namei(&uchar, 0);
if(ip == NULL)
return;
u.u_arg[1]++;
open1(ip, u.u_arg[1], 0);
}
/*
* creat system call
*
* bug fix reported May-June 1977
* UNIX NEWS Vol 2, No. 5 p5-3
* George Goble - Purdue University
*/
creat()
{
register *ip;
extern uchar;
ip = namei(&uchar, 1);
if(ip == NULL) {
if(u.u_error)
return;
if( (u.u_cdir->i_nlink == 0) /* bug fix */
&& (fubyte(u.u_arg[0]) != '/') ) { /* bug fix */
u.u_error = ENOENT; /* bug fix */
err: iput(u.u_pdir); /* namei left parent dir locked */
/* bug fix */
return; /* bug fix */
}
ip = maknode(u.u_arg[1]&07777&(~ISVTX));
if (ip==NULL)
goto err; /* bug fix */
open1(ip, FWRITE, 2);
} else
open1(ip, FWRITE, 1);
}
/*
* common code for open and creat.
* Check permissions, allocate an open file structure,
* and call the device open routine if any.
*/
open1(ip, mode, trf)
int *ip;
{
register struct file *fp;
register *rip, m;
int i;
rip = ip;
m = mode;
#ifdef NETSYS
if( m < 1 || m > 3 )
{
m = (FREAD|FWRITE);
mode--;
}
#endif NETSYS
if(trf != 2) {
if(m&FREAD)
access(rip, IREAD);
if(m&FWRITE) {
access(rip, IWRITE);
if((rip->i_mode&IFMT) == IFDIR)
u.u_error = EISDIR;
}
}
if(u.u_error)
goto out;
#ifdef NETSYS
if ( ((rip->i_mode & IFMT) == IFCHR)
&& (rip->i_addr[0].d_major <= 0177777) )
{
/* normal net open */
netopen( rip,mode );
return;
}
#endif NETSYS
if(trf)
itrunc(rip);
prele(rip);
if ((fp = falloc()) == NULL)
goto out;
fp->f_flag = m&(FREAD|FWRITE);
fp->f_inode = rip;
i = u.u_ar0[R0];
openi(rip, m&FWRITE);
if(u.u_error == 0)
return;
u.u_ofile[i] = NULL;
fp->f_count--;
out:
iput(rip);
}
/*
* close system call
*/
close()
{
register *fp;
fp = getf(u.u_ar0[R0]);
if(fp == NULL)
return;
u.u_ofile[u.u_ar0[R0]] = NULL;
closef(fp);
}
/*
* seek system call
*/
seek()
{
int n[2];
register *fp, t;
fp = getf(u.u_ar0[R0]);
if(fp == NULL)
return;
#ifdef NETSYS
if( fp->f_flag&FNET)
{
u.u_error = ESNET;
return;
}
#endif NETSYS
if(fp->f_flag&FPIPE) {
u.u_error = ESPIPE;
return;
}
t = u.u_arg[1];
if(t > 2) {
n[1] = u.u_arg[0]<<9;
n[0] = u.u_arg[0]>>7;
if(t == 3)
n[0] =& 0777;
} else {
n[1] = u.u_arg[0];
n[0] = 0;
if(t!=0 && n[1]<0)
n[0] = -1;
}
switch(t) {
case 1:
case 4:
n[0] =+ fp->f_offset[0];
dpadd(n, fp->f_offset[1]);
break;
default:
n[0] =+ fp->f_inode->i_size0&0377;
dpadd(n, fp->f_inode->i_size1);
case 0:
case 3:
;
}
fp->f_offset[1] = n[1];
fp->f_offset[0] = n[0];
}
/*
* link system call
*/
link()
{
register *ip, *xp;
extern uchar;
ip = namei(&uchar, 0);
if(ip == NULL)
return;
if(ip->i_nlink >= 127) {
u.u_error = EMLINK;
goto out;
}
if((ip->i_mode&IFMT)==IFDIR && !suser())
goto out;
/*
* unlock to avoid possibly hanging the namei
*/
ip->i_flag =& ~ILOCK;
u.u_dirp = u.u_arg[1];
xp = namei(&uchar, 1);
if(xp != NULL) {
u.u_error = EEXIST;
iput(xp);
}
if(u.u_error)
goto out;
if(u.u_pdir->i_dev != ip->i_dev) {
iput(u.u_pdir);
u.u_error = EXDEV;
goto out;
}
wdir(ip);
ip->i_nlink++;
ip->i_flag =| IUPD;
out:
iput(ip);
}
/*
* mknod system call
*/
mknod()
{
register *ip;
extern uchar;
if(suser()) {
ip = namei(&uchar, 1);
if(ip != NULL) {
u.u_error = EEXIST;
goto out;
}
}
if(u.u_error)
return;
ip = maknode(u.u_arg[1]);
if (ip==NULL)
return;
ip->i_addr[0] = u.u_arg[2];
out:
iput(ip);
}
/*
* sleep system call
* not to be confused with the sleep internal routine.
*/
sslep()
{
/*
* modified 31Oct77 by J.S.Kravitz and R.J.Balocca to
* make sleep better (no unneeded swaps)
*
* note that sleep now changes 'alarm' value, it is not
* a good idea to enter sleep with an alarm set... not
* a common mode of programming anyway
*/
alarm (); /* set up alarm clock with parameters from user */
spl6();
while (u.u_procp->p_clktim)
sleep (&u.u_procp->p_clktim, PSLEP);
spl0();
}
/*
* access system call
*/
saccess()
{
extern uchar;
register svuid, svgid;
register *ip;
svuid = u.u_uid;
svgid = u.u_gid;
u.u_uid = u.u_ruid;
u.u_gid = u.u_rgid;
ip = namei(&uchar, 0);
if (ip != NULL) {
if (u.u_arg[1]&(IREAD>>6))
access(ip, IREAD);
if (u.u_arg[1]&(IWRITE>>6))
access(ip, IWRITE);
if (u.u_arg[1]&(IEXEC>>6))
access(ip, IEXEC);
iput(ip);
}
u.u_uid = svuid;
u.u_gid = svgid;
}
#ifdef NETSYS
/*
* tell the ncpdaemon to reset all he knows about a host
*/
net_reset()
{
struct
{
char net_op;
char net_rsthost;
}nreset;
register char *ip;
extern uchar;
if (!suser())
{
return; /* suser sets u.u_error to EPERM */
}
nreset.net_op = 4; /* assign reset opcode for daemon */
nreset.net_rsthost = u.u_ar0[R0]; /* assign host number*/
switch ( to_ncp (&nreset, 2, 0) ) /* send instruction to daemon */
{
case 0:
u.u_ar0[R0] = 0;
return;
case 1:
u.u_error = ENCPBUF;
return;
default: /* -1 and anything else we dont know about */
u.u_error = ENCPNO;
return;
}
}
#endif NETSYS