use GETF macro where appropriate

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

/*      sys_generic.c   6.3     84/08/22        */

#include "../h/param.h"
#include "../h/systm.h"
#include "../h/dir.h"
#include "../h/user.h"
#include "../h/ioctl.h"
#include "../h/file.h"
#include "../h/proc.h"
#include "../h/uio.h"
#include "../h/kernel.h"
#include "../h/stat.h"

/*
* Read system call.
*/
read()
{
       register struct a {
               int     fdes;
               char    *cbuf;
               unsigned count;
       } *uap = (struct a *)u.u_ap;
       struct uio auio;
       struct iovec aiov;

       aiov.iov_base = (caddr_t)uap->cbuf;
       aiov.iov_len = uap->count;
       auio.uio_iov = &aiov;
       auio.uio_iovcnt = 1;
       rwuio(&auio, UIO_READ);
}

readv()
{
       register struct a {
               int     fdes;
               struct  iovec *iovp;
               int     iovcnt;
       } *uap = (struct a *)u.u_ap;
       struct uio auio;
       struct iovec aiov[16];          /* XXX */

       if (uap->iovcnt <= 0 || uap->iovcnt > sizeof(aiov)/sizeof(aiov[0])) {
               u.u_error = EINVAL;
               return;
       }
       auio.uio_iov = aiov;
       auio.uio_iovcnt = uap->iovcnt;
       u.u_error = copyin((caddr_t)uap->iovp, (caddr_t)aiov,
           (unsigned)(uap->iovcnt * sizeof (struct iovec)));
       if (u.u_error)
               return;
       rwuio(&auio, UIO_READ);
}

/*
* Write system call
*/
write()
{
       register struct a {
               int     fdes;
               char    *cbuf;
               int     count;
       } *uap = (struct a *)u.u_ap;
       struct uio auio;
       struct iovec aiov;

       auio.uio_iov = &aiov;
       auio.uio_iovcnt = 1;
       aiov.iov_base = uap->cbuf;
       aiov.iov_len = uap->count;
       rwuio(&auio, UIO_WRITE);
}

writev()
{
       register struct a {
               int     fdes;
               struct  iovec *iovp;
               int     iovcnt;
       } *uap = (struct a *)u.u_ap;
       struct uio auio;
       struct iovec aiov[16];          /* XXX */

       if (uap->iovcnt <= 0 || uap->iovcnt > sizeof(aiov)/sizeof(aiov[0])) {
               u.u_error = EINVAL;
               return;
       }
       auio.uio_iov = aiov;
       auio.uio_iovcnt = uap->iovcnt;
       u.u_error = copyin((caddr_t)uap->iovp, (caddr_t)aiov,
           (unsigned)(uap->iovcnt * sizeof (struct iovec)));
       if (u.u_error)
               return;
       rwuio(&auio, UIO_WRITE);
}

rwuio(uio, rw)
       register struct uio *uio;
       enum uio_rw rw;
{
       struct a {
               int     fdes;
       };
       register struct file *fp;
       register struct iovec *iov;
       int i, count;

       GETF(fp, ((struct a *)u.u_ap)->fdes);
       if ((fp->f_flag&(rw==UIO_READ ? FREAD : FWRITE)) == 0) {
               u.u_error = EBADF;
               return;
       }
       uio->uio_resid = 0;
       uio->uio_segflg = UIO_USERSPACE;
       iov = uio->uio_iov;
       for (i = 0; i < uio->uio_iovcnt; i++) {
               if (iov->iov_len < 0) {
                       u.u_error = EINVAL;
                       return;
               }
               uio->uio_resid += iov->iov_len;
               if (uio->uio_resid < 0) {
                       u.u_error = EINVAL;
                       return;
               }
               iov++;
       }
       count = uio->uio_resid;
       uio->uio_offset = fp->f_offset;
       if ((u.u_procp->p_flag&SOUSIG) == 0 && setjmp(&u.u_qsave)) {
               if (uio->uio_resid == count)
                       u.u_eosys = RESTARTSYS;
       } else
               u.u_error = (*fp->f_ops->fo_rw)(fp, rw, uio);
       u.u_r.r_val1 = count - uio->uio_resid;
       fp->f_offset += u.u_r.r_val1;
}

/*
* Ioctl system call
*/
ioctl()
{
       register struct file *fp;
       struct a {
               int     fdes;
               int     cmd;
               caddr_t cmarg;
       } *uap;
       register int com;
       register u_int size;
       char data[IOCPARM_MASK+1];

       uap = (struct a *)u.u_ap;
       GETF(fp, uap->fdes);
       if ((fp->f_flag & (FREAD|FWRITE)) == 0) {
               u.u_error = EBADF;
               return;
       }
       com = uap->cmd;

#if defined(vax) && defined(COMPAT)
       /*
        * Map old style ioctl's into new for the
        * sake of backwards compatibility (sigh).
        */
       if ((com&~0xffff) == 0) {
               com = mapioctl(com);
               if (com == 0) {
                       u.u_error = EINVAL;
                       return;
               }
       }
#endif
       if (com == FIOCLEX) {
               u.u_pofile[uap->fdes] |= UF_EXCLOSE;
               return;
       }
       if (com == FIONCLEX) {
               u.u_pofile[uap->fdes] &= ~UF_EXCLOSE;
               return;
       }

       /*
        * Interpret high order word to find
        * amount of data to be copied to/from the
        * user's address space.
        */
       size = (com &~ (IOC_INOUT|IOC_VOID)) >> 16;
       if (size > sizeof (data)) {
               u.u_error = EFAULT;
               return;
       }
       if (com&IOC_IN) {
               if (size) {
                       u.u_error =
                           copyin(uap->cmarg, (caddr_t)data, (u_int)size);
                       if (u.u_error)
                               return;
               } else
                       *(caddr_t *)data = uap->cmarg;
       } else if ((com&IOC_OUT) && size)
               /*
                * Zero the buffer on the stack so the user
                * always gets back something deterministic.
                */
               bzero((caddr_t)data, size);
       else if (com&IOC_VOID)
               *(caddr_t *)data = uap->cmarg;

       switch (com) {

       case FIONBIO:
               u.u_error = fset(fp, FNDELAY, *(int *)data);
               return;

       case FIOASYNC:
               u.u_error = fset(fp, FASYNC, *(int *)data);
               return;

       case FIOSETOWN:
               u.u_error = fsetown(fp, *(int *)data);
               return;

       case FIOGETOWN:
               u.u_error = fgetown(fp, (int *)data);
               return;
       }
       u.u_error = (*fp->f_ops->fo_ioctl)(fp, com, data);
       /*
        * Copy any data to user, size was
        * already set and checked above.
        */
       if (u.u_error == 0 && (com&IOC_OUT) && size)
               u.u_error = copyout(data, uap->cmarg, (u_int)size);
}

int     unselect();
int     nselcoll;
/*
* Select system call.
*/
select()
{
       register struct uap  {
               int     nd;
               long    *in, *ou, *ex;
               struct  timeval *tv;
       } *uap = (struct uap *)u.u_ap;
       int ibits[3], obits[3];
       struct timeval atv;
       int s, ncoll, mask;
       label_t lqsave;

       obits[0] = obits[1] = obits[2] = 0;
       if (uap->nd > NOFILE)
               uap->nd = NOFILE;       /* forgiving, if slightly wrong */
       mask = (1 << uap->nd) - 1;

#define getbits(name, x) \
       if (uap->name) { \
               u.u_error = copyin((caddr_t)uap->name, (caddr_t)&ibits[x], \
                   sizeof (ibits[x])); \
               if (u.u_error) \
                       goto done; \
               ibits[x] &= mask; \
       } else \
               ibits[x] = 0;
       getbits(in, 0);
       getbits(ou, 1);
       getbits(ex, 2);
#undef  getbits

       if (uap->tv) {
               u.u_error = copyin((caddr_t)uap->tv, (caddr_t)&atv,
                       sizeof (atv));
               if (u.u_error)
                       goto done;
               if (itimerfix(&atv)) {
                       u.u_error = EINVAL;
                       goto done;
               }
               s = spl7(); timevaladd(&atv, &time); splx(s);
       }
retry:
       ncoll = nselcoll;
       u.u_procp->p_flag |= SSEL;
       u.u_r.r_val1 = selscan(ibits, obits);
       if (u.u_error || u.u_r.r_val1)
               goto done;
       s = spl6();
       /* this should be timercmp(&time, &atv, >=) */
       if (uap->tv && (time.tv_sec > atv.tv_sec ||
           time.tv_sec == atv.tv_sec && time.tv_usec >= atv.tv_usec)) {
               splx(s);
               goto done;
       }
       if ((u.u_procp->p_flag & SSEL) == 0 || nselcoll != ncoll) {
               u.u_procp->p_flag &= ~SSEL;
               splx(s);
               goto retry;
       }
       u.u_procp->p_flag &= ~SSEL;
       if (uap->tv) {
               lqsave = u.u_qsave;
               if (setjmp(&u.u_qsave)) {
                       untimeout(unselect, (caddr_t)u.u_procp);
                       u.u_error = EINTR;
                       splx(s);
                       goto done;
               }
               timeout(unselect, (caddr_t)u.u_procp, hzto(&atv));
       }
       sleep((caddr_t)&selwait, PZERO+1);
       if (uap->tv) {
               u.u_qsave = lqsave;
               untimeout(unselect, (caddr_t)u.u_procp);
       }
       splx(s);
       goto retry;
done:
#define putbits(name, x) \
       if (uap->name) { \
               int error = copyout((caddr_t)&obits[x], (caddr_t)uap->name, \
                   sizeof (obits[x])); \
               if (error) \
                       u.u_error = error; \
       }
       putbits(in, 0);
       putbits(ou, 1);
       putbits(ex, 2);
#undef putbits
}

unselect(p)
       register struct proc *p;
{
       register int s = spl6();

       switch (p->p_stat) {

       case SSLEEP:
               setrun(p);
               break;

       case SSTOP:
               unsleep(p);
               break;
       }
       splx(s);
}

selscan(ibits, obits)
       int *ibits, *obits;
{
       register int which, bits, i;
       int flag;
       struct file *fp;
       int n = 0;

       for (which = 0; which < 3; which++) {
               bits = ibits[which];
               obits[which] = 0;
               switch (which) {

               case 0:
                       flag = FREAD; break;

               case 1:
                       flag = FWRITE; break;

               case 2:
                       flag = 0; break;
               }
               while (i = ffs(bits)) {
                       bits &= ~(1<<(i-1));
                       fp = u.u_ofile[i-1];
                       if (fp == NULL) {
                               u.u_error = EBADF;
                               break;
                       }
                       if ((*fp->f_ops->fo_select)(fp, flag)) {
                               obits[which] |= (1<<(i-1));
                               n++;
                       }
               }
       }
       return (n);
}

/*ARGSUSED*/
seltrue(dev, flag)
       dev_t dev;
       int flag;
{

       return (1);
}

selwakeup(p, coll)
       register struct proc *p;
       int coll;
{

       if (coll) {
               nselcoll++;
               wakeup((caddr_t)&selwait);
       }
       if (p) {
               int s = spl6();
               if (p->p_wchan == (caddr_t)&selwait)
                       setrun(p);
               else if (p->p_flag & SSEL)
                       p->p_flag &= ~SSEL;
               splx(s);
       }
}