r_ieee_vals_.rar_John A

/* Copyright (c) 1984 AT&T */ /* All Rights Reserved */ /* THIS IS UNPUBLISHED PROPRIETARY SOURCE CODE OF AT&T */ /* The copyright notice above does not evidence any */ /* actual or intended publication of such source code. */ #ident "@(#)pk1.c 1.1 92/07/30" /* from SVR3.2 uucp:pk1.c 2.5 */ #include "uucp.h" #include "pk.h" #include <sys/buf.h> #define PKMAXSTMSG 40 #define CONNODATA 20 /* Max Continuous Non Valid Data Count */ #define NTIMEOUT 50 /* Experimental */ int Connodata = 0; /* Continuous Non Valid Data Count */ int Ntimeout = 0; /* Experimental */ extern int Retries; /* * Translation of states from numbers to letters, in such a way as to be * meaningful to John Q. UUCPadministrator */ static struct { int state; char *msg; } st_trans[] = { DEAD, "Dead!", INITa, "INIT code a", INITb, "INIT code b", LIVE, "O.K.", RXMIT, "Rcv/Xmit", RREJ, "RREJ?", PDEBUG, "PDEBUG?", DRAINO, "Draino...", WAITO, "Waiting", DOWN, "Link down", RCLOSE, "RCLOSE?", BADFRAME, "Bad frame", -1, "End of the line", }; /* * start initial synchronization. */ struct pack * pkopen(ifn, ofn) int ifn, ofn; { register struct pack *pk; register char **bp; register int i; char *calloc(); if ((pk = (struct pack *) calloc(1, sizeof (struct pack))) == NULL) return(NULL); pk->p_ifn = ifn; pk->p_ofn = ofn; pk->p_xsize = pk->p_rsize = PACKSIZE; pk->p_rwindow = pk->p_swindow = WINDOWS; /* * allocate input window */ 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) return(NULL); pk->p_rwindow = i; /* * start synchronization */ pk->p_msg = pk->p_rmsg = M_INITA; pkoutput(pk); for (i = 0; i < PKMAXSTMSG; i++) { pkgetpack(pk); if ((pk->p_state & LIVE) != 0) break; } if (i >= PKMAXSTMSG) 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 * */ #define GETRIES 10 /* * Byte collection. */ pkgetpack(ipk) struct pack *ipk; { register char *p; register struct pack *pk; register struct header *h; unsigned short sum; int k, tries, ifn, noise; char **bp, hdchk; pk = ipk; /* * If we are known to be DOWN, or if we've received too many garbage * packets or timeouts, give up without a fight. */ if ((pk->p_state & DOWN) || Connodata > CONNODATA || Ntimeout > NTIMEOUT) pkfail(); ifn = pk->p_ifn; h = &pk->p_ihbuf; /* * Attempt no more than GETRIES times to read a packet. The only valid * exit from this loop is a return. Break forces a failure. */ for (tries = 0; tries < GETRIES; tries++) { /* * Read header. * First look for SYN. If more than 3 * packetsize characters * go by w/o a SYN, request a retransmit. */ p = (caddr_t) h; noise = 0; for ( ; ; ) { if (pkcget(ifn, p, 1) != SUCCESS) { DEBUG(7, "Alarm while looking for SYN -- request RXMIT\n", 0); goto retransmit; } if (*p == SYN) break; /* got it */ if (noise++ > 3 * pk->p_rsize) { DEBUG(7, "No SYN in %d characters -- request RXMIT\n", noise); goto retransmit; } } /* Now look for remainder of header */ if (pkcget(ifn, p+1, HDRSIZ - 1) != SUCCESS) { DEBUG(7, "Alarm while looking for header -- request RXMIT\n", 0); goto retransmit; } /* Validate the header */ Connodata++; hdchk = p[1] ^ p[2] ^ p[3] ^ p[4]; sum = ((unsigned) p[2] & 0377) | ((unsigned) p[3] << 8); h->sum = sum; k = h->ksize; if (hdchk != h->ccntl) { /* bad header */ DEBUG(7, "bad header checksum\n", 0); return; } if (k == 9) { /* control packet */ if (((h->sum + h->cntl) & 0xffff) == CHECK) { pkcntl(h->cntl, pk); xlatestate(pk, 7); } else { /* bad header */ DEBUG(7, "bad header (k == 9) 0%o\n", h->cntl&0xff); pk->p_state |= BADFRAME; } return; } /* data packet */ if (k && pksizes[k] != pk->p_rsize) return; pk->p_rpr = h->cntl & MOD8; pksack(pk); if ((bp = pk->p_ipool) == NULL) { DEBUG(7, "bp NULL\n", 0); return; } pk->p_ipool = (char **) *bp; /* Header checks out, go for data */ if (pkcget(pk->p_ifn, (char *) bp, pk->p_rsize) == SUCCESS) { pkdata(h->cntl, h->sum, pk, bp); Ntimeout = 0; return; } DEBUG(7, "Alarm while reading data -- request RXMIT\n", 0); retransmit: /* * Transmission error or excessive noise. Send a RXMIT * and try again. */ 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); } DEBUG(7, "pkgetpack failed after %d tries\n", tries); pkfail(); } /* * Translate pk->p_state into something printable. */ xlatestate(pk, dbglvl) register struct pack *pk; { register int i; char delimc = ' ', msgline[80], *buf = msgline; if (Debug < dbglvl) return; sprintf(buf, "state -"); buf += strlen(buf); for(i = 0; st_trans[i].state != -1; i++) { if (pk->p_state&st_trans[i].state){ sprintf(buf, "%c[%s]", delimc, st_trans[i].msg); buf += strlen(buf); delimc = '&'; } } sprintf(buf, " (0%o)\n", pk->p_state); DEBUG(dbglvl, "%s", msgline); } pkdata(c, sum, pk, bp) register struct pack *pk; unsigned short sum; char c; char **bp; { register x; int t; char m; 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) goto slot; } drop: *bp = (char *)pk->p_ipool; pk->p_ipool = bp; return; slot: m = mask[x]; pk->p_imap |= m; pk->p_is[x] = c; pk->p_isum[x] = sum; pk->p_ib[x] = (char *)bp; } #define PKMAXBUF 128 /* * 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; int x; char cntl; { register char *p; register short checkword; register 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 */ if (Debug >= 9) xlatecntl(1, cntl); p = (caddr_t) & pk->p_ohbuf; if (x < 0) { if ((*Write)(pk->p_ofn, p, HDRSIZ) != HDRSIZ) { DEBUG(4, "pkxstart, write failed, %s\n", sys_errlist[errno]); logent(sys_errlist[errno], "PKXSTART WRITE"); pkfail(); /* NOT REACHED */ } } else { char buf[PKMAXBUF + HDRSIZ]; memcpy(buf, p, HDRSIZ); memcpy(buf+HDRSIZ, pk->p_ob[x], pk->p_xsize); if ((*Write)(pk->p_ofn, buf, pk->p_xsize + HDRSIZ) != pk->p_xsize + HDRSIZ) { DEBUG(4, "pkxstart, write failed, %s\n", sys_errlist[errno]); logent(sys_errlist[errno], "PKXSTART WRITE"); pkfail(); /* NOT REACHED */ } Connodata = 0; } if (pk->p_msg) pkoutput(pk); } /* * get n characters from input * b -> buffer for characters * fn -> file descriptor * n -> requested number of characters * return: * SUCCESS -> n chars successfully read * FAIL -> o.w. */ jmp_buf Getjbuf; cgalarm() { longjmp(Getjbuf, 1); } pkcget(fn, b, n) register int n; register char *b; register int fn; { register int ret; register int donap; if (n == 0) return(SUCCESS); donap = (linebaudrate > 0 && linebaudrate < 4800); if (setjmp(Getjbuf)) { Ntimeout++; DEBUG(4, "pkcget: alarm %d\n", Ntimeout); return(FAIL); } (void) signal(SIGALRM, cgalarm);