4.3BSD-Reno/src/usr.bin/uucp/pk1.c
#ifndef lint
static char sccsid[] = "@(#)pk1.c 5.11 (Berkeley) 4/5/88";
#endif
#include <signal.h>
#include "uucp.h"
#include "pk.h"
#include <setjmp.h>
#ifdef BSD4_2
#include <sys/time.h>
#include <sys/uio.h>
#else /* !BSD4_2 */
struct iovec {
caddr_t iov_base;
int iov_len;
}
#endif /* !BSD4_2 */
#ifdef VMS
#include <eunice/eunice.h>
#include <vms/iodef.h>
#include <vms/ssdef.h>
int iomask[2];
#endif VMS
#define PKMAXSTMSG 40
#define MAXPKTIME 32 /* was 16 */
#define CONNODATA 10
#define MAXTIMEOUT 32
extern int errno;
extern int Retries;
extern char *sys_errlist[];
extern jmp_buf Sjbuf;
extern char *malloc();
int Connodata = 0;
int Ntimeout = 0;
int pktimeout = 4;
int pktimeskew = 2;
/*
* packet driver support routines
*
*/
extern struct pack *pklines[];
/*
* start initial synchronization.
*/
struct pack *
pkopen(ifn, ofn)
int ifn, ofn;
{
register struct pack *pk;
register char **bp;
register int i;
if ((pk = (struct pack *) malloc(sizeof (struct pack))) == NULL)
return NULL;
bzero((caddr_t) pk, sizeof (struct pack));
pk->p_ifn = ifn;
pk->p_ofn = ofn;
pk->p_xsize = pk->p_rsize = PACKSIZE;
pk->p_rwindow = pk->p_swindow = WINDOWS;
/* allocate input windows */
for (i = 0; i < pk->p_rwindow; i++) {
if ((bp = (char **) malloc((unsigned)pk->p_xsize)) == NULL)
break;
*bp = (char *) pk->p_ipool;
pk->p_ipool = bp;
}
if (i == 0) {
DEBUG(1, "pkopen: can't malloc i = 0\n", CNULL);
return NULL;
}
pk->p_rwindow = i;
/* start synchronization */
pk->p_msg = pk->p_rmsg = M_INITA;
for (i = 0; i < NPLINES; i++) {
if (pklines[i] == NULL) {
pklines[i] = pk;
break;
}
}
if (i >= NPLINES) {
DEBUG(1,"pkopen: i>=NPLINES\n", CNULL);
return NULL;
}
pkoutput(pk);
for (i = 0; i < PKMAXSTMSG; i++) {
pkgetpack(pk);
if ((pk->p_state & LIVE) != 0)
break;
}
if (i >= PKMAXSTMSG) {
DEBUG(1, "pkopen: i>= PKMAXSTMSG\n", CNULL);
return NULL;
}
pkreset(pk);
return pk;
}
/*
* input framing and block checking.
* frame layout for most devices is:
*
* S|K|X|Y|C|Z| ... data ... |
*
* where S == initial synch byte
* K == encoded frame size (indexes pksizes[])
* X, Y == block check bytes
* C == control byte
* Z == XOR of header (K^X^Y^C)
* data == 0 or more data bytes
*
*/
int pksizes[] = {
1, 32, 64, 128, 256, 512, 1024, 2048, 4096, 1
};
#define GETRIES 10
/*
* Pseudo-dma byte collection.
*/
pkgetpack(pk)
register struct pack *pk;
{
int k, tries, noise;
register char *p;
register struct header *h;
unsigned short sum;
int ifn;
char **bp;
char hdchk;
if ((pk->p_state & DOWN) || Connodata > CONNODATA || Ntimeout > MAXTIMEOUT)
pkfail();
ifn = pk->p_ifn;
/* find HEADER */
for (tries = 0, noise = 0; tries < GETRIES; ) {
p = (caddr_t) &pk->p_ihbuf;
if (pkcget(ifn, p, 1) == SUCCESS) {
if (*p++ == SYN) {
if (pkcget(ifn, p, HDRSIZ-1) == SUCCESS)
break;
} else {
if (noise++ < 10 || noise < (3*pk->p_rsize))
continue;
}
DEBUG(4, "Noisy line - set up RXMIT\n", CNULL);
noise = 0;
}
/* set up retransmit or REJ */
tries++;
Retries++;
pk->p_msg |= pk->p_rmsg;
if (pk->p_msg == 0)
pk->p_msg |= M_RR;
if ((pk->p_state & LIVE) == LIVE)
pk->p_state |= RXMIT;
pkoutput(pk);
}
if (tries >= GETRIES) {
DEBUG(4, "tries = %d\n", tries);
pkfail();
}
Connodata++;
h = (struct header *) &pk->p_ihbuf;
p = (caddr_t) h;
hdchk = p[1] ^ p[2] ^ p[3] ^ p[4];
p += 2;
sum = (unsigned) *p++ & 0377;
sum |= (unsigned) *p << 8;
h->sum = sum;
DEBUG(7, "rec h->cntl 0%o\n", h->cntl&0xff);
k = h->ksize;
if (hdchk != h->ccntl) {
/* bad header */
DEBUG(7, "bad header 0%o,", hdchk&0xff);
DEBUG(7, "h->ccntl 0%o\n", h->ccntl&0xff);
return;
}
if (k == 9) {
if (((h->sum + h->cntl) & 0xffff) == CHECK) {
pkcntl(h->cntl, pk);
DEBUG(7, "state - 0%o\n", pk->p_state);
} else {
/* bad header */
pk->p_state |= BADFRAME;
DEBUG(7, "bad header (k==9) 0%o\n", h->cntl&0xff);
}
return;
}
if (k && pksizes[k] == pk->p_rsize) {
pk->p_rpr = h->cntl & MOD8;
DEBUG(7, "end pksack 0%o\n", pk->p_rpr);
pksack(pk);
bp = pk->p_ipool;
if (bp == NULL) {
DEBUG(7, "bp NULL %s\n", "");
return;
}
pk->p_ipool = (char **) *bp;
Connodata = 0;
} else
return;
if (pkcget(pk->p_ifn, (char *) bp, pk->p_rsize) == SUCCESS) {
pkdata(h->cntl, h->sum, pk, (char **) bp);
} else {
*bp = (char *)pk->p_ipool;
pk->p_ipool = bp;
}
}
pkdata(c, sum, pk, bp)
char c;
unsigned short sum;
register struct pack *pk;
char **bp;
{
register x;
register int t;
if (pk->p_state & DRAINO || !(pk->p_state & LIVE)) {
pk->p_msg |= pk->p_rmsg;
pkoutput(pk);
goto drop;
}
t = next[pk->p_pr];
for(x = pk->p_pr; x != t; x = (x-1)&7) {
if (pk->p_is[x] == 0) {
pk->p_imap |= mask[x];
pk->p_is[x] = c;
pk->p_isum[x] = sum;
pk->p_ib[x] = (char *)bp;
return;
}
}
drop:
*bp = (char *)pk->p_ipool;
pk->p_ipool = bp;
}
/*
* setup input transfers
*
* Start transmission on output device associated with pk.
* For asynch devices (t_line==1) framing is
* imposed. For devices with framing and crc
* in the driver (t_line==2) the transfer is
* passed on to the driver.
*/
pkxstart(pk, cntl, x)
register struct pack *pk;
char cntl;
register x;
{
register char *p;
short checkword;
char hdchk;
p = (caddr_t) &pk->p_ohbuf;
*p++ = SYN;
if (x < 0) {
*p++ = hdchk = 9;
checkword = cntl;
} else {
*p++ = hdchk = pk->p_lpsize;
checkword = pk->p_osum[x] ^ (unsigned)(cntl & 0377);
}
checkword = CHECK - checkword;
*p = checkword;
hdchk ^= *p++;
*p = checkword>>8;
hdchk ^= *p++;
*p = cntl;
hdchk ^= *p++;
*p = hdchk;
/* writes */
DEBUG(7, "send 0%o\n", cntl&0xff);
p = (caddr_t) & pk->p_ohbuf;
if (x < 0) {
if(write(pk->p_ofn, p, HDRSIZ) != HDRSIZ) {
alarm(0);
logent("PKXSTART write failed", sys_errlist[errno]);
longjmp(Sjbuf, 4);
}
} else {
struct iovec iov[2];
iov[0].iov_base = p;
iov[0].iov_len = HDRSIZ;
iov[1].iov_base = pk->p_ob[x];
iov[1].iov_len = pk->p_xsize;
if (writev(pk->p_ofn, iov, 2) < 0) {
alarm(0);
logent("PKXSTART write failed", sys_errlist[errno]);
longjmp(Sjbuf, 5);
}
#ifdef 0
char buf[PKMAXBUF + HDRSIZ], *b;
int i;
for (i = 0, b = buf; i < HDRSIZ; i++)
*b++ = *p++;
for (i = 0, p = pk->p_ob[x]; i < pk->p_xsize; i++)
*b++ = *p++;
if (write(pk->p_ofn, buf, pk->p_xsize + HDRSIZ)
!= (HDRSIZ + pk->p_xsize)) {
alarm(0);
logent("PKXSTART write failed", sys_errlist[errno]);
longjmp(Sjbuf, 5);
}
#endif 0
Connodata = 0;
}
if (pk->p_msg)
pkoutput(pk);
}
/*
* get n characters from input
*
* return codes:
* n - number of characters returned
* 0 - end of file
*/
jmp_buf Getjbuf;
cgalarm()
{
longjmp(Getjbuf, 1);
}
pkcget(fn, b, n)
int fn;
register char *b;
register int n;
{
register int ret;
extern int linebaudrate;
#ifdef BSD4_2
long r, itime = 100000L; /* guess it's been 1/10th second since we
last read the line */
struct timeval tv;
#endif BSD4_2
#ifdef VMS
short iosb[4];
int SYS$QioW(); /* use this for long reads on vms */
#endif VMS
if (setjmp(Getjbuf)) {
Ntimeout++;
DEBUG(4, "pkcget: alarm %d\n", pktimeout * 1000 + Ntimeout);
pktimeout += pktimeskew;
if (pktimeout > MAXPKTIME)
pktimeout = MAXPKTIME;
return FAIL;
}
signal(SIGALRM, cgalarm);
alarm(pktimeout);
while (n > 0) {
#ifdef BSD4_2
if (linebaudrate > 0) {
r = n * 100000L;
r = r / linebaudrate;
r = (r * 100) - itime;
itime = 0;
/* we predict that more than 1/50th of a
second will go by before the read will
give back all that we want. */
if (r > 20000) {
tv.tv_sec = r / 1000000L;
tv.tv_usec = r % 1000000L;
DEBUG(11, "PKCGET stall for %d", tv.tv_sec);
DEBUG(11, ".%06d sec\n", tv.tv_usec);
(void) select (0, (int *)0, (int *)0, (int *)0, &tv);
}
}
#endif BSD4_2
#ifndef VMS
ret = read(fn, b, n);
#else VMS
_$Cancel_IO_On_Signal = FD_FAB_Pointer[fn];
ret = SYS$QioW(_$EFN,(FD_FAB_Pointer[fn]->fab).fab$l_stv,
IO$_READVBLK|IO$M_NOFILTR|IO$M_NOECHO,
iosb,0,0,b,n,0,
iomask,0,0);
_$Cancel_IO_On_Signal = 0;
if (ret == SS$_NORMAL)
ret = iosb[1]+iosb[3]; /* get length of transfer */
else
ret = 0;
#endif VMS
if (ret == 0) {
alarm(0);
return FAIL;
}
if (ret <= 0) {
alarm(0);
logent(sys_errlist[errno],"FAILED pkcget Read");
longjmp(Sjbuf, 6);
}
b += ret;
n -= ret;
}
alarm(0);
return SUCCESS;
}