ckcfn3.c

linux终端仿真程序

/*  C K C F N 3  --  Packet buffer management for C-Kermit  */

/* (plus assorted functions tacked on at the end) */

/*
  Author: Frank da Cruz <[e-mail]>,
  Columbia University Academic Information Systems, New York City.

  Copyright (C) 1985, 1996, Trustees of Columbia University in the City of New
  York.  The C-Kermit software may not be, in whole or in part, licensed or
  sold for profit as a software product itself, nor may it be included in or
  distributed with commercial products or otherwise distributed by commercial
  concerns to their clients or customers without written permission of the
  Office of Kermit Development and Distribution, Columbia University.  This
  copyright notice must not be removed, altered, or obscured.
*/

#include "ckcsym.h"
#include "ckcdeb.h"
#include "ckcasc.h"
#include "ckcker.h"
#include "ckcxla.h"

#ifndef NODISPO
#ifdef pdp11
#define NODISPO
#endif /* pdpd11 */
#endif /* NODISPO */

extern int unkcs, wmax, wcur, discard, bctu, bctl, local, fdispla, what,
  sendmode, opnerr, dest;
extern long sendstart;

extern char * ofn2;
extern char ofn1[];
extern int ofn1x;

extern int xflg, remfile, remappd;
extern CHAR *data;
extern char filnam[];
#ifndef NOFRILLS
extern int rprintf, rmailf;		/* REMOTE MAIL, PRINT */
extern char * printfile;
extern int printpipe;
char optbuf[100];			/* Options for MAIL or REMOTE PRINT */
#endif /* NOFRILLS */
extern int wslots;
extern int fblksiz, frecl, forg, frecfm, fncact, fncsav, fcctrl, lf_opts;
#ifdef pdp11
  extern CHAR srvcmd[];
  extern char tmpbuf[];
  CHAR *pktmsg = (CHAR *) tmpbuf;
#else
#ifdef DYNAMIC
  extern CHAR *srvcmd;
  extern CHAR *pktmsg;
#else
  extern CHAR srvcmd[];
  extern CHAR pktmsg[];
#endif /* DYNAMIC */
#endif /* pdp11 */

extern int binary, spsiz;
extern int pktnum, cxseen, czseen, nfils, stdinf;
extern int memstr, stdouf, keep, sndsrc, hcflg;
extern int server, en_cwd, en_mai, en_pri;

extern int
  atenci, atenco, atdati, atdato, atleni, atleno, atblki, atblko,
  attypi, attypo, atsidi, atsido, atsysi, atsyso, atdisi, atdiso; 

#ifdef STRATUS
extern int atfrmi, atfrmo, atcrei, atcreo, atacti, atacto;
#endif /* STRATUS */

#ifdef datageneral
extern int quiet;
#endif /* datageneral */

extern long fsize, filcnt, ffc, tfc;

#ifndef NOCSETS
extern int tcharset, fcharset;
extern int ntcsets;
extern struct csinfo tcsinfo[], fcsinfo[];

/* Pointers to translation functions */
#ifdef CK_ANSIC
extern CHAR (*xls[MAXTCSETS+1][MAXFCSETS+1])(CHAR); /* Character set */
extern CHAR (*xlr[MAXTCSETS+1][MAXFCSETS+1])(CHAR); /* translation functions */
extern CHAR (*rx)(CHAR); /* Pointer to input character translation function */
extern CHAR (*sx)(CHAR); /* Pointer to output character translation function */
#else
extern CHAR (*xls[MAXTCSETS+1][MAXFCSETS+1])();	/* Character set */
extern CHAR (*xlr[MAXTCSETS+1][MAXFCSETS+1])();	/* translation functions. */
extern CHAR (*rx)();	/* Pointer to input character translation function */
extern CHAR (*sx)();    /* Pointer to output character translation function */
#endif /* CK_ANSIC */
#endif /* NOCSETS */

/* Variables global to Kermit that are defined in this module */

int winlo;				/* packet number at low window edge  */

int sbufnum;				/* number of free buffers */
int dum001 = 1234;			/* protection... */
int sbufuse[MAXWS];			/* buffer in-use flag */
int dum003 = 1111;
int rbufnum;				/* number of free buffers */
int dum002 = 4321;			/* more protection */
int rbufuse[MAXWS];			/* buffer in-use flag */
int sseqtbl[64];			/* sequence # to buffer # table */
int rseqtbl[64];			/* sequence # to buffer # table */
int sacktbl[64];			/* sequence # ack table */

#ifdef DYNAMIC
struct pktinfo *s_pkt = NULL;		/* array of pktinfo structures */
struct pktinfo *r_pkt = NULL;		/* array of pktinfo structures */
#else
struct pktinfo s_pkt[MAXWS];		/* array of pktinfo structures */
struct pktinfo r_pkt[MAXWS];		/* array of pktinfo structures */
#endif /* DYNAMIC */

#ifdef DEBUG
char xbuf[200];				/* For debug logging */
#endif /* DEBUG */

#ifdef DYNAMIC
CHAR *bigsbuf = NULL, *bigrbuf = NULL;
#else
char bigsbt[8];				/* Protection (shouldn't need this). */
					/* BUT DON'T REMOVE IT! */
CHAR bigsbuf[SBSIZ + 5];		/* Send-packet buffer area */
char bigrbt[8];				/* Safety padding */
CHAR bigrbuf[RBSIZ + 5];		/* Receive-packet area */
#endif
int bigsbsiz = SBSIZ;			/* Sizes of big send & rcv buffers. */
int bigrbsiz = RBSIZ;

#ifdef VMS
int zchkpath(char *s);
#endif /* VMS */

/* FUNCTIONS */

/* For sanity, use "i" for buffer slots, "n" for packet numbers. */

/* I N I B U F S */

/*
  Allocates the big send and receive buffers.
  Call with size for big send buffer (s) and receive buffer (r).
  These sizes can be different.
  Attempts to allocate buffers of the requested size, but if it can't,
  it will allocate smaller ones.
  Sets global variables bigsbsiz and bigrbsiz to the actual sizes,
  and bigsbuf and bigrbuf pointing to the actual buffers.
  Designed to be called more than once.
  Returns 0 on success, -1 on failure.
*/

CHAR *bigbufp = NULL;

int
inibufs(s,r) int s, r; {
#ifdef DYNAMIC
    unsigned
      int size;
#ifdef OS2
    unsigned		/* Don't you wish everybody had unsigned long... */
#endif /* OS2 */  
      long z;
    int x;

    debug(F101,"inibufs s","",s);
    debug(F101,"inibufs r","",r);

    if (s < 80 || r < 80) return(-1);	/* Validate arguments. */

    if (!s_pkt) {			/* Allocate packet info structures */
	if (!(s_pkt = (struct pktinfo *) malloc(sizeof(struct pktinfo)*MAXWS)))
	  fatal("ini_pkts: no memory for s_pkt");
    }
    for (x = 0; x < MAXWS; x++)
      s_pkt[x].pk_adr = NULL;		/* Initialize addresses */

    if (!r_pkt) {
	if (!(r_pkt = (struct pktinfo *) malloc(sizeof(struct pktinfo)*MAXWS)))
	  fatal("ini_pkts: no memory for s_pkt");
    }
    for (x = 0; x < MAXWS; x++)
      r_pkt[x].pk_adr = NULL;		/* Initialize addresses */

    if (!srvcmd) {			/* Allocate srvcmd buffer */
	srvcmd = (CHAR *) malloc(r + 100);
	if (!srvcmd) return(-1);
	*srvcmd = NUL;
    }
    if (!pktmsg) {			/* Allocate pktmsg buffer */
	pktmsg = (CHAR *) malloc(81);
	if (!pktmsg) return(-1);
	*pktmsg = NUL;
    }

    if (bigbufp) {			/* Free previous buffers, if any. */
	free(bigbufp);
	bigbufp = NULL;
    }
    size = s + r + 40;			/* Combined requested size + padding */
    z  = (unsigned) s + (unsigned) r + 40;
    debug(F101,"inibufs size 1","",size);
    debug(F101,"inibufs size z","",z);
    if ((long) size != z) {
	debug(F100,"inibufs overflow","",0);
	size = 65535;
    }	

    /* Try to get the space.  If malloc fails, try to get a little less. */
    /* (Obviously, this algorithm can be refined.) */

    while (!(bigbufp = (CHAR *) malloc(size))) {
	debug(F101,"inibufs bigbuf malloc failed","",size);
	size = (size * 2) / 3;		/* Failed, cut size by 1/3. */
	if (size < 200)			/* Try again until too small. */
	  return(-1);
    }
    debug(F101,"inibufs size 2","",size); /* OK, we got some space. */

/*
  Now divide the allocated space between the send and receive buffers in the
  requested proportion.  The natural formula would be (s / (s + r)) * size
  (for the send buffer), but that doesn't work with integer arithmetic and we
  can't use floating point because some machines don't have it.  This can be
  rearranged as (s * size) / (s + r).  But (s * size) can be VERY large, too
  large for 32 bits.  So let's do it this way.  This arithmetic works for
  buffer sizes up to about 5,000,000.
*/
#define FACTOR 20L
    z = ( (long) s * FACTOR ) / ( (long) s + (long) r );
    x = ( z * ( (long) size / FACTOR ) );
    if (x < 0) return(-1);		/* Catch overflow */

    bigsbsiz = x - 5;			/* Size of send buffer */
    bigsbuf = bigbufp;			/* Address of send buffer */
    debug(F101,"inibufs bigsbsiz","",bigsbsiz);

    bigrbsiz = size - x - 5;		/* Size of receive buffer */
    bigrbuf = bigbufp + x;		/* Addresss of receive buffer */
    debug(F101,"inibufs bigrbsiz","",bigrbsiz);

    return(0);				/* Success */
#else					/* No dynamic allocation */
    bigsbsiz = SBSIZ;			/* Just use the symbols */
    bigrbsiz = RBSIZ;			/* ... */
    return(0);				/* Success. */
#endif /* DYNAMIC */
}


/* M A K E B U F  --  Makes and clears a new buffers.  */

/* Call with: */
/*  slots:  number of buffer slots to make, 1 to 32 */
/*  bufsiz: size of the big buffer */
/*  buf:    address of the big buffer */
/*  xx:     pointer to array of pktinfo structures for these buffers */

/* Subdivides the big buffer into "slots" buffers. */

/* Returns: */
/*  -1 if too many or too few slots requested,     */
/*  -2 if slots would be too small.      */
/*   n (positive) on success = size of one buffer. */
/*   with pktinfo structure initialized for this set of buffers. */

int
makebuf(slots,bufsiz,buf,xx)
/* makebuf */ int slots, bufsiz; CHAR buf[]; struct pktinfo *xx; {

    CHAR *a;
    int i, size;

    debug(F101,"makebuf","",slots);
    debug(F101,"makebuf bufsiz","",bufsiz);
    debug(F101,"makebuf MAXWS","",MAXWS);

    if (slots > MAXWS || slots < 1) return(-1);
    if (bufsiz < slots * 10 ) return(-2);

    size = bufsiz / slots;		/* Divide up the big buffer. */
    a = buf;				/* Address of first piece. */

    for (i = 0; i < slots; i++) {
	struct pktinfo *x = &xx[i];
	x->bf_adr = a;			/* Address of this buffer */
	x->bf_len = size;		/* Length of this buffer */
	x->pk_len = 0;			/* Length of data field */
        x->pk_typ = ' ';		/* packet type */
	x->pk_seq = -1;			/* packet sequence number */
        x->pk_rtr = 0;			/* retransmissions */
	*a = '\0';			/* Clear the buffer */
	a += size;			/* Position to next buffer slot */
    }
    return(size);
}

/*  M A K S B U F  --  Makes the send-packet buffer  */

int
mksbuf(slots) int slots; {
    int i, x;
    sbufnum = 0;
    if ((x = makebuf(slots,bigsbsiz,bigsbuf,s_pkt)) < 0) {
	debug(F101,"mksbuf makebuf return","",x);
	return(x);
    }
    debug(F101,"mksbuf makebuf return","",x);
    for (i = 0; i < 64; i++) {		/* Initialize sequence-number- */
	sseqtbl[i] = -1;		/* to-buffer-number table. */
        sacktbl[i] = 0;
    }
    for (i = 0; i < MAXWS; i++)
      sbufuse[i] = 0;			/* Mark each buffer as free */
    sbufnum = slots;
    wcur = 0;
    return(x);
}

/*  M A K R B U F  --  Makes the receive-packet buffer  */

int
mkrbuf(slots) int slots; {
    int i, x;
    rbufnum = 0;
    if ((x = makebuf(slots,bigrbsiz,bigrbuf,r_pkt)) < 0) {
	debug(F101,"mkrbuf makebuf return","",x);
	return(x);
    }
    debug(F101,"mkrbuf makebuf return","",x);
    for (i = 0; i < 64; i++) {		/* Initialize sequence-number- */
	rseqtbl[i] = -1;		/* to-buffer-number table. */
    }
    for (i = 0; i < MAXWS; i++)
      rbufuse[i] = 0;			/* Mark each buffer as free */
    rbufnum = slots;
    wcur = 0;
    return(x);
}

/*  W I N D O W  --  Resize the window to n  */

int
window(n) int n; {
    debug(F101,"window","",n);
    if (n < 1 || n > MAXWS) return(-1);
    if (mksbuf(n) < 0) return(-1);
    if (mkrbuf(n) < 0) return(-1);
    wslots = n;
#ifdef DEBUG
    if (deblog) dumpsbuf();
    if (deblog) dumprbuf();
#endif /* DEBUG */
    return(0);
}

/*  G E T S B U F  --  Allocate a send-buffer.  */

/*  Call with packet sequence number to allocate buffer for. */
/*  Returns: */
/*   -4 if argument is invalid (negative, or greater than 63) */
/*   -3 if buffers were thought to be available but really weren't (bug!) */
/*   -2 if the number of free buffers is negative (bug!) */
/*   -1 if no free buffers. */
/*   0 or positive, packet sequence number, with buffer allocated for it. */

int
getsbuf(n) int n; {			/* Allocate a send-buffer */
    int i;
    if (n < 0 || n > 63) {
	debug(F101,"getsbuf bad arg","",n);
	return(-4);	/* Bad argument */
    }
    debug(F101,"getsbuf, packet","",n);
    debug(F101,"getsbuf, sbufnum","",sbufnum);
    if (sbufnum == 0) return(-1);	/* No free buffers. */
    if (sbufnum < 0) return(-2);	/* Shouldn't happen. */
    for (i = 0; i < wslots; i++)	/* Find the first one not in use. */
      if (sbufuse[i] == 0) {		/* Got one? */
	  sbufuse[i] = 1;		/* Mark it as in use. */
	  sbufnum--;			/* One less free buffer. */
	  *s_pkt[i].bf_adr = '\0';	/* Zero the buffer data field */
	  s_pkt[i].pk_seq = n;		/* Put in the sequence number */
          sseqtbl[n] = i;		/* Back pointer from sequence number */
          sacktbl[n] = 0;		/* ACK flag */
	  s_pkt[i].pk_len = 0;		/* Data field length now zero. */
	  s_pkt[i].pk_typ = ' ';	/* Blank the packet type too. */
	  s_pkt[i].pk_rtr = 0;		/* Zero the retransmission count */
	  data = s_pkt[i].bf_adr + 7;	/* Set global "data" address. */
	  if ((what & (W_SEND|W_REMO)) && (++wcur > wmax))
	    wmax = wcur;		/* For statistics. */
	  return(n);			/* Return its index. */
      }
    sbufnum = 0;			/* Didn't find one. */
    return(-3);				/* Shouldn't happen! */
}

int
getrbuf() {				/* Allocate a receive buffer */
    int i;
    debug(F101,"getrbuf rbufnum","",rbufnum);
    debug(F101,"getrbuf wslots","",wslots);
    debug(F101,"getrbuf dum002","",dum002);
    debug(F101,"getrbuf dum003","",dum003);
    if (rbufnum == 0) return(-1);	/* No free buffers. */
    if (rbufnum < 0) return(-2);	/* Shouldn't happen. */
    for (i = 0; i < wslots; i++)	/* Find the first one not in use. */
      if (rbufuse[i] == 0) {		/* Got one? */
	  rbufuse[i] = 1;		/* Mark it as in use. */
	  *r_pkt[i].bf_adr = '\0';	/* Zero the buffer data field */
	  rbufnum--;			/* One less free buffer. */
	  debug(F101,"getrbuf new rbufnum","",rbufnum);
	  if ((what & W_RECV) && (++wcur > wmax))
	    wmax = wcur;		/* For statistics. */
	  return(i);			/* Return its index. */
      }
    debug(F101,"getrbuf foulup","",i);
    rbufnum = 0;			/* Didn't find one. */
    return(-3);				/* Shouldn't happen! */
}

/*  F R E E S B U F  --  Free send-buffer for given packet sequence number */

/*  Returns:  */
/*   1 upon success  */
/*  -1 if specified buffer does not exist */

int