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1991/0522/port/stfcall.c (diff list | history)

port/stfcall.c on 1991/0521
1991/0521    
#include	"u.h" 
#include	"lib.h" 
#include	"mem.h" 
#include	"dat.h" 
#include	"fns.h" 
#include	"errno.h" 
 
#include	"fcall.h"
1991/0522    
#define DPRINT 	if(fcalldebug)print
1991/0521    
 
int fcalldebug = 0; 
 
typedef struct Fcalld	Fcalld; 
 
struct Fcalld{ 
	int	dev;		/* ref. for debug output */ 
	int	state; 
	int	type;		/* of current message */ 
	int	need;		/* bytes remaining in current message */ 
	int	nhdr;		/* bytes of header treasured up in hdr */ 
	uchar	hdr[16]; 
}; 
 
enum { 
	Startup, Startup1, Begin, Header, Data 
}; 
 
/* 
 *  fcall stream module definition 
 */ 
static void fcalliput(Queue*, Block*); 
static void fcalloput(Queue*, Block*); 
static void fcallopen(Queue*, Stream*); 
static void fcallclose(Queue*); 
static void fcallreset(void); 
Qinfo fcallinfo = 
{ 
	fcalliput, 
	fcalloput, 
	fcallopen, 
	fcallclose, 
	"fcall", 
	fcallreset 
}; 
 
static Block *	putmsg(Queue*, Block*, int); 
 
static uchar msglen[] = { 
	  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, 
	  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, 
	  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, 
	  0,  0,  3,  3,  3,  3,  0, 67,  5,  3, 89, 13,  7,  5, 33, 13, 
	  6, 13, 38, 13, 15,  8, 16,  7,  5,  5,  5,  5,  5,121,121,  5, 
	 35, 13,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, 
	  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, 
	  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, 
	  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, 
	  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, 
	  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, 
	  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, 
	  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, 
	  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, 
	  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, 
	  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0 
}; 
static void 
fcallreset(void) 
{} 
 
static void 
fcallopen(Queue *q, Stream *s) 
{ 
	Fcalld *f; 
 
	DPRINT("fcallopen %d\n", s->dev); 
 
	q->ptr = allocb(sizeof(Fcalld)); 
	f = (Fcalld *)((Block *)q->ptr)->base; 
	f->dev = s->dev; 
	f->state = Startup; 
	f->type = 0; 
	f->need = 0; 
	f->nhdr = 0; 
} 
 
static void 
fcallclose(Queue * q) 
{ 
	Fcalld *f = (Fcalld *)((Block *)q->ptr)->base; 
 
	DPRINT("fcallstclose %d\n", f->dev); 
	freeb(q->ptr); 
	q->ptr = 0; 
} 
 
void 
fcalloput(Queue *q, Block *bp) 
{ 
	PUTNEXT(q, bp); 
} 
 
 
static void 
fcalliput(Queue *q, Block *bp) 
{ 
	Fcalld *f = (Fcalld *)((Block *)q->ptr)->base; 
	int len, n; 
 
	len = BLEN(bp); 
	DPRINT("fcalliput %d: blen=%d\n", f->dev, len); 
	if(bp->type != M_DATA){ 
		DPRINT("fcalliput %d: type=%d\n", f->dev, bp->type); 
		PUTNEXT(q, bp); 
		return; 
	} 
	bp->flags &= ~S_DELIM; 
	if(len == 0){ 
		freeb(bp); 
		return; 
	} 
	while(len > 0)switch(f->state){ 
	case Startup: 
		if (len == 1 && bp->rptr[0] == 'O'){ 
			DPRINT("fcalliput %d: O\n", f->dev); 
			PUTNEXT(q, bp); 
			f->state = Startup1; 
			return; 
		} 
		if(bp->rptr[0] == 'O' && bp->rptr[1] == 'K'){ 
			DPRINT("fcalliput %d: OK\n", f->dev); 
			bp = putmsg(q, bp, 2); 
			len -= 2; 
		} 
		f->state = Begin; 
		break; 
 
	case Startup1: 
		if(bp->rptr[0] == 'K'){ 
			DPRINT("fcalliput %d: K\n", f->dev); 
			bp = putmsg(q, bp, 1); 
			len -= 1; 
			f->state = Begin; 
			break; 
		} 
		f->type = 'O'; 
		f->need = msglen['O']-1; 
		f->state = Data; 
		DPRINT("fcalliput %d: type=%d, need=%d\n", 
			f->dev, f->type, f->need); 
		break; 
 
	case Begin: 
		f->type = bp->rptr[0]; 
		f->need = msglen[f->type]; 
		f->nhdr = 0; 
		if(f->type == Twrite || f->type == Rread) 
			f->state = Header; 
		else 
			f->state = Data; 
		DPRINT("fcalliput %d: type=%d, need=%d\n", 
			f->dev, f->type, f->need); 
		break; 
 
	case Header: 
		n = f->need; 
		if(n > len) 
			n = len; 
		memmove(&f->hdr[f->nhdr], bp->rptr, n); 
		f->nhdr += n; 
		DPRINT("fcalliput %d: nhdr=%d\n", 
			f->dev, f->nhdr); 
		if(n == f->need){ 
			f->need += f->hdr[f->nhdr-3]; 
			f->need += f->hdr[f->nhdr-2] << 8; 
			f->state = Data; 
			DPRINT("fcalliput %d: need=%d\n", 
				f->dev, f->need); 
		} 
		/* fall through */ 
 
	case Data: 
		if(f->need > len){ 
			f->need -= len; 
			PUTNEXT(q, bp); 
			return; 
		} 
		bp = putmsg(q, bp, f->need); 
		len -= f->need; 
		f->state = Begin; 
		break; 
	} 
} 
 
static Block * 
putmsg(Queue *q, Block *bp, int n) 
{ 
	Block *xbp; 
	int k; 
 
	DPRINT("putmsg: n=%d\n\n", n); 
	k = BLEN(bp) - n; 
	if(k == 0){ 
		bp->flags |= S_DELIM; 
		PUTNEXT(q, bp); 
		return 0; 
	} 
	if(n <= k){ 
		xbp = allocb(n); 
		memmove(xbp->wptr, bp->rptr, n); 
		xbp->wptr += n; 
		bp->rptr += n; 
		xbp->flags |= S_DELIM; 
		PUTNEXT(q, xbp); 
		return bp; 
	} 
	xbp = allocb(k); 
	memmove(xbp->wptr, bp->rptr+n, k); 
	xbp->wptr += k; 
	bp->wptr -= k; 
	bp->flags |= S_DELIM; 
	PUTNEXT(q, bp); 
	return xbp; 
}


source code copyright © 1990-2005 Lucent Technologies; see license
Plan 9 distribution
comments to russ cox (rsc@swtch.com)