int
_er90b_write(struct fdinfo *fio, bitptr bufptr, int nbytes,
struct ffsw *retstat, int fulp, int *ubc)
{
int ret;
int nbt = 0; /* number of bytes transferred so far */
int nbreq; /* number of bytes requested this request */
char *buf;
ER90BYT *f;
int zero = 0;
struct ffsw dumstat;
buf = BPTR2CP(bufptr);
if ((BPBITOFF(bufptr) & 7) != 0 || *ubc != 0)
ERETURN(retstat, FDC_ERR_UBC, 0);
nbreq = nbytes;
if (fio->rwflag == POSITIN) {
f = (ER90BYT *)fio->lyr_info;
if (f->tpos) {
ret = _tape_tpwait(f->fd, &(f->tpos));
if (ret < 0)
ERETURN(retstat, errno, 0);
}
}
else if (fio->rwflag == READIN) {
/* write after read requires position to zero */
ret = _er90b_pos(fio, FP_RSEEK, &zero, 1,
&dumstat);
if (ret < 0) {
*retstat = dumstat;
return(ERR);
}
}
if (nbreq > 0) {
again:
/* It is not safe to reissue the write if it fails */
/* with EINTR. Some data may have been transferred */
ret= write(fio->realfd, buf, nbreq);
if (ret < 0)
ERETURN(retstat, errno, nbt);
nbt += ret;
/*
* The assumption is made here that the system will never return
* zero bytes on a non-zero request without an error!
*/
if (nbt < nbytes) {
buf += ret;
nbreq -= ret;
goto again;
}
}
else if (nbytes < 0)
ERETURN(retstat, FDC_ERR_REQ, 0);
SETSTAT(retstat, FFCNT, nbt);
fio->rwflag = WRITIN;
return (nbt);
}
int
_er90b_writea(struct fdinfo *fio, bitptr bufptr, int nbytes,
struct ffsw *retstat, int fulp, int *ubc)
{
int ret = 0;
char *buf;
ER90BYT *f;
int zero = 0;
struct ffsw dumstat;
buf = BPTR2CP(bufptr);
if ((BPBITOFF(bufptr) & 7) != 0 || *ubc != 0)
ERETURN(retstat, FDC_ERR_UBC, 0);
if (fio->rwflag == POSITIN) {
f = (ER90BYT *)fio->lyr_info;
if (f->tpos) {
ret = _tape_tpwait(f->fd, &(f->tpos));
if (ret < 0)
ERETURN(retstat, errno, 0);
}
}
else if (fio->rwflag == READIN) {
/* write after read requires position to zero */
ret = _er90b_pos(fio, FP_RSEEK, &zero, 1,
&dumstat);
if (ret < 0) {
*retstat = dumstat;
return(ERR);
}
}
if (nbytes > 0) {
CLRFFSTAT(*retstat); /* flag async in progress */
ret= writea(fio->realfd, buf, nbytes,
(struct iosw *)retstat, 0);
if (ret < 0)
ERETURN(retstat, errno, 0);
}
else if (nbytes < 0) {
ERETURN(retstat, FDC_ERR_REQ, 0);
}
else { /* nbytes == 0 */
retstat->sw_flag = 1;
FFSTAT(*retstat) = FFCNT; /* I/O is done, and other stat */
/* fields are already set. */
}
fio->rwflag = WRITIN;
return (ret);
}
