vt: convert from event to threads

the event library doesnt do any flow control. if the host
keeps sending data while the user is mousing arround,
extract() will collect the data until memory fills up.

so instead we abandon the event library and convert
the program to use channels.

5 files changed, 191 insertions, 244 deletions

diff --git a/sys/src/cmd/vt/cons.h b/sys/src/cmd/vt/cons.h
index fbf022953..f415e4d3b 100644
--- a/sys/src/cmd/vt/cons.h
+++ b/sys/src/cmd/vt/cons.h
@@ -81,7 +81,7 @@ extern Image *fgdefault;
 extern int cursoron;
 extern int nocolor;
 
-extern void curson(int);
+extern void curson(void);
 extern void cursoff(void);
 extern void setdim(int, int);
 
diff --git a/sys/src/cmd/vt/event.c b/sys/src/cmd/vt/event.c
deleted file mode 100644
index 44d100fd1..000000000
--- a/sys/src/cmd/vt/event.c
+++ /dev/null
@@ -1,70 +0,0 @@
-#include <u.h>
-#include <libc.h>
-#include <draw.h>
-#include <event.h>
-#include "cons.h"
-
-#define	BUFSIZ	4000
-
-extern int	outfd;
-
-int	hostpid;
-
-void
-edie(void)
-{
-	static int dead = 0;
-
-	if(dead++ > 0) return;
-	close(outfd);
-	postnote(PNGROUP, getpid(), "exit");
-}
-
-static int
-start_host(void)
-{
-	int	fd;
-
-	cs = consctl();
-
-	switch((hostpid = rfork(RFPROC|RFNAMEG|RFFDG|RFNOTEG))) {
-	case 0:
-		fd = open("/dev/cons", OREAD);
-		dup(fd,0);
-		if(fd != 0)
-			close(fd);
-		fd = open("/dev/cons", OWRITE);
-		dup(fd,1);
-		dup(fd,2);
-		if(fd != 1 && fd !=2)
-			close(fd);
-		execl("/bin/rc","rcX",nil);
-		fprint(2,"failed to start up rc\n");
-		_exits("rc");
-	case -1:
-		fprint(2,"rc startup: fork error\n");
-		_exits("rc_fork");
-	}
-
-	return open("/mnt/cons/data", ORDWR);
-}
-
-void
-ebegin(int Ehost)
-{
-
-	atexit(edie);
-
-	einit(Emouse|Ekeyboard);
-
-	outfd = start_host();
-	if( estart(Ehost, outfd, BUFSIZ) != Ehost) {
-		exits("event init error");
-	}
-}
-
-void
-send_interrupt(void)
-{
-	postnote(PNGROUP, hostpid,"interrupt");
-}
diff --git a/sys/src/cmd/vt/event.h b/sys/src/cmd/vt/event.h
deleted file mode 100644
index baa108623..000000000
--- a/sys/src/cmd/vt/event.h
+++ /dev/null
@@ -1,13 +0,0 @@
-#define BSIZE	4000
-#define MOUSE	0
-#define KBD	1
-#define	HOST	2
-#define HOST_BLOCKED	1
-#define KBD_BLOCKED	2
-
-typedef struct IOEvent {
-	short	key;
-	short	size;
-	uchar	data[BSIZE];
-} IOEvent;
-
diff --git a/sys/src/cmd/vt/main.c b/sys/src/cmd/vt/main.c
index ebbc63d98..6bea55e9d 100644
--- a/sys/src/cmd/vt/main.c
+++ b/sys/src/cmd/vt/main.c
@@ -1,21 +1,18 @@
 #include <u.h>
 #include <libc.h>
 #include <draw.h>
-#include <event.h>
-#include <bio.h>
+#include <thread.h>
+#include <mouse.h>
 #include <keyboard.h>
+#include <bio.h>
 #include "cons.h"
 
-enum{
-	Ehost		= 4,
-};
-
 char	*menutext2[] = {
 	"backup",
 	"forward",
 	"reset",
 	"clear",
-	"send",
+	"paste",
 	"page",
 	0
 };
@@ -93,48 +90,117 @@ int	NS;
 int	CW;
 int	XMARGIN;
 int	YMARGIN;
-Consstate *cs;
+
 Mouse	mouse;
+Rune	kbdchar;
+
+Mousectl	*mc;
+Keyboardctl	*kc;
+Channel		*hc;
+Consstate	*cs;
 
 int	debug;
 int	nocolor;
 int	logfd = -1;
-int	outfd = -1;
+int	hostfd = -1;
+int	hostpid;
 Biobuf	*snarffp = 0;
-
-char	*host_buf;
-char	*hostp;				/* input from host */
-
-int	host_bsize = 2*BSIZE;
-int	hostlength;			/* amount of input from host */
+Rune	*hostbuf, *hostbufp;
 char	echo_input[BSIZE];
 char	*echop = echo_input;		/* characters to echo, after canon */
 char	sendbuf[BSIZE];	/* hope you can't type ahead more than BSIZE chars */
-char	*sendp = sendbuf;
+char	*sendbufp = sendbuf;
 
 char *term;
 struct funckey *fk;
 
 /* functions */
 void	initialize(int, char **);
-void	ebegin(int);
 int	waitchar(void);
+void	waitio(void);
 int	rcvchar(void);
-void	set_input(char *);
-void	set_host(Event *);
 void	bigscroll(void);
 void	readmenu(void);
 void	selection(void);
-void	eresized(int);
 void	resize(void);
 void	send_interrupt(void);
 int	alnum(int);
 void	escapedump(int,uchar *,int);
 Rune*	onscreenp(int, int);
 
+int
+start_host(void)
+{
+	int	fd;
+
+	switch((hostpid = rfork(RFPROC|RFNAMEG|RFFDG|RFNOTEG))) {
+	case 0:
+		fd = open("/dev/cons", OREAD);
+		dup(fd,0);
+		if(fd != 0)
+			close(fd);
+		fd = open("/dev/cons", OWRITE);
+		dup(fd,1);
+		dup(fd,2);
+		if(fd != 1 && fd !=2)
+			close(fd);
+		execl("/bin/rc","rcX",nil);
+		fprint(2,"failed to start up rc\n");
+		_exits("rc");
+	case -1:
+		fprint(2,"rc startup: fork error\n");
+		_exits("rc_fork");
+	}
+	return open("/mnt/cons/data", ORDWR);
+}
+
+void
+send_interrupt(void)
+{
+	postnote(PNGROUP, hostpid, "interrupt");
+}
+
 void
-main(int argc, char **argv)
+hostreader(void*)
 {
+	char cb[BSIZE+1], *cp;
+	Rune *rb, *rp;
+	int n, r;
+
+	n = 0;
+	while((r = read(hostfd, cb+n, BSIZE-n)) > 0){
+		n += r;
+		rb = mallocz((n+1)*sizeof(Rune), 0);
+		for(rp = rb, cp = cb; n > 0; n -= r, cp += r){
+			if(!fullrune(cp, n))
+				break;
+			r = chartorune(rp, cp);
+			if(*rp != 0)
+				rp++;
+		}
+		if(rp > rb){
+			*rp = 0;
+			sendp(hc, rb);
+		} else {
+			free(rb);
+		}
+		if(n > 0) memmove(cb, cp, n);
+	}
+	sendp(hc, nil);
+}
+
+static void
+shutdown(void)
+{
+	postnote(PNGROUP, getpid(), "exit");
+	threadexitsall(nil);
+}
+
+void
+threadmain(int argc, char **argv)
+{
+	rfork(RFNAMEG|RFNOTEG|RFENVG);
+	atexit(shutdown);
 	initialize(argc, argv);
 	emulate();
 }
@@ -153,8 +219,6 @@ initialize(int argc, char **argv)
 	int i, blkbg;
 	char *fontname, *p;
 
-	rfork(RFNAMEG|RFNOTEG|RFENVG);
-
 	fontname = nil;
 	term = "vt100";
 	fk = vt100fk;
@@ -196,18 +260,19 @@ initialize(int argc, char **argv)
 		break;
 	}ARGEND;
 
-	host_buf = mallocz(host_bsize, 1);
-	hostp = host_buf;
-	hostlength = 0;
-
-	if(initdraw(0, fontname, term) < 0){
-		fprint(2, "%s: initdraw failed: %r\n", term);
-		exits("initdraw");
-	}
-	werrstr("");		/* clear spurious error messages */
-	ebegin(Ehost);
-
+	if(initdraw(0, fontname, term) < 0)
+		sysfatal("inidraw failed: %r");
+	if((mc = initmouse("/dev/mouse", screen)) == nil)
+		sysfatal("initmouse failed: %r");
+	if((kc = initkeyboard("/dev/cons")) == nil)
+		sysfatal("initkeyboard failed: %r");
+	if((cs = consctl()) == nil)
+		sysfatal("consctl failed: %r");
 	cs->raw = rflag;
+	hc = chancreate(sizeof(Rune*), 0);
+	if((hostfd = start_host()) >= 0)
+		proccreate(hostreader, nil, BSIZE+1024);
+
 	histp = hist;
 	menu2.item = menutext2;
 	menu3.item = menutext3;
@@ -276,25 +341,19 @@ newline(void)
 void
 cursoff(void)
 {
-	draw(screen, Rpt(pt(x, y), addpt(pt(x, y), Pt(CW,NS))), 
-		cursback, nil, cursback->r.min);
+	draw(screen, Rpt(pt(x, y), addpt(pt(x, y), Pt(CW,NS))), cursback, nil, cursback->r.min);
 }
 
 void
-curson(int bl)
+curson(void)
 {
-	Image *col;
+	Image *col = (blocked || hostfd < 0) ? red : bordercol;
 
 	if(!cursoron){
 		cursoff();
 		return;
 	}
-
 	draw(cursback, cursback->r, screen, nil, pt(x, y));
-	if(bl)
-		col = red;
-	else
-		col = bordercol;
 	border(screen, Rpt(pt(x, y), addpt(pt(x, y), Pt(CW,NS))), 2, col, ZP);
 }
 
@@ -357,58 +416,58 @@ canon(char *ep, Rune c)
 	case Kpgdown:
 		return SCROLL;
 	case '\b':
-		if(sendp > sendbuf){
-			sendp = backrune(sendbuf, sendp);
+		if(sendbufp > sendbuf){
+			sendbufp = backrune(sendbuf, sendbufp);
 			*ep++ = '\b';
 			*ep++ = ' ';
 			*ep++ = '\b';
 		}
 		break;
 	case 0x15:	/* ^U line kill */
-		sendp = sendbuf;
+		sendbufp = sendbuf;
 		*ep++ = '^';
 		*ep++ = 'U';
 		*ep++ = '\n';
 		break;
 	case 0x17:	/* ^W word kill */
-		while(sendp > sendbuf && !alnum(*sendp)) {
-			sendp = backrune(sendbuf, sendp);
+		while(sendbufp > sendbuf && !alnum(*sendbufp)) {
+			sendbufp = backrune(sendbuf, sendbufp);
 			*ep++ = '\b';
 			*ep++ = ' ';
 			*ep++ = '\b';
 		}
-		while(sendp > sendbuf && alnum(*sendp)) {
-			sendp = backrune(sendbuf, sendp);
+		while(sendbufp > sendbuf && alnum(*sendbufp)) {
+			sendbufp = backrune(sendbuf, sendbufp);
 			*ep++ = '\b';
 			*ep++ = ' ';
 			*ep++ = '\b';
 		}
 		break;
 	case '\177':	/* interrupt */
-		sendp = sendbuf;
+		sendbufp = sendbuf;
 		send_interrupt();
 		return(NEWLINE);
 	case '\021':	/* quit */
 	case '\r':
 	case '\n':
-		if(sendp < &sendbuf[BSIZE])
-			*sendp++ = '\n';
-		sendnchars((int)(sendp-sendbuf), sendbuf);
-		sendp = sendbuf;
+		if(sendbufp < &sendbuf[BSIZE])
+			*sendbufp++ = '\n';
+		sendnchars((int)(sendbufp-sendbuf), sendbuf);
+		sendbufp = sendbuf;
 		if(c == '\n' || c == '\r')
 			*ep++ = '\n';
 		*ep = 0;
 		return(NEWLINE);
 	case '\004':	/* EOT */
-		if(sendp == sendbuf) {
+		if(sendbufp == sendbuf) {
 			sendnchars(0,sendbuf);
 			*ep = 0;
 			return(NEWLINE);
 		}
 		/* fall through */
 	default:
-		if(sendp < &sendbuf[BSIZE-UTFmax])
-			sendp += runetochar(sendp, &c);
+		if(sendbufp < &sendbuf[BSIZE-UTFmax])
+			sendbufp += runetochar(sendbufp, &c);
 		ep += runetochar(ep, &c);
 		break;
 	}
@@ -432,53 +491,30 @@ sendfk(char *name)
 int
 waitchar(void)
 {
-	Event e;
-	int c;
-	int newmouse;
-	int wasblocked;
-	Rune kbdchar = 0;
-	char echobuf[4*BSIZE];
+	static char echobuf[4*BSIZE];
 
 	for(;;) {
 		if(resize_flag)
 			resize();
-		wasblocked = blocked;
 		if(backp)
 			return(0);
-		if(ecanmouse()){
-			if(button1())
-				selection();
-			else if(button2() || button3())
-				readmenu();
-		}
 		if(snarffp) {
-			static Rune lastc = ~0;
+			int c;
 
 			if((c = Bgetrune(snarffp)) < 0) {
-				if(lastc != '\n')
-					write(outfd,"\n",1);
 				Bterm(snarffp);
-				snarffp = 0;
-				if(lastc != '\n') {
-					lastc = ~0;
-					return('\n');
-				}
-				lastc = ~0;
+				snarffp = nil;
 				continue;
 			}
-			lastc = c;
-			write(outfd, echobuf, runetochar(echobuf, &lastc));
-			return(c);
+			kbdchar = c;
 		}
-		if(!blocked && host_avail())
-			return(rcvchar());
-		if(kbdchar > 0) {
+		if(kbdchar) {
 			if(backc){
 				backc = 0;
 				backup(backc);
 			}
 			if(blocked)
-				resize();
+				resize_flag = 1;
 			if(cs->raw) {
 				switch(kbdchar){
 				case Kup:
@@ -547,51 +583,65 @@ waitchar(void)
 					sendnchars(runetochar(echobuf, &kbdchar), echobuf);
 					break;
 				}
-			} else if(canon(echobuf,kbdchar) == SCROLL) {
-				if(!blocked)
-					bigscroll();
-			} else
-				strcat(echo_input,echobuf);
+			} else {
+				switch(canon(echobuf, kbdchar)){
+				case SCROLL:
+					if(!blocked)
+						bigscroll();
+					break;
+				default:
+					strcat(echo_input,echobuf);
+				}
+			}
 			blocked = 0;
 			kbdchar = 0;
 			continue;
 		}
-		curson(wasblocked);	/* turn on cursor while we're waiting */
-		flushimage(display, 1);
-		do {
-			newmouse = 0;
-			switch(eread(blocked ? Emouse|Ekeyboard : 
-					       Emouse|Ekeyboard|Ehost, &e)) {
-			case Emouse:
-				mouse = e.mouse;
-				if(button1())
-					selection();
-				else if(button2() || button3())
-					readmenu();
-				else if(resize_flag == 0) {
-					/* eresized() is triggered by special mouse event */
-					newmouse = 1;
-				}
-				break;
-			case Ekeyboard:
-				kbdchar = e.kbdc;
-				break;
-			case Ehost:
-				set_host(&e);
-				break;
-			default:
-				perror("protocol violation");
-				exits("protocol violation");
-			}
-		} while(newmouse == 1);
-		cursoff();	/* turn cursor back off */
+		if(!blocked){
+			if(host_avail())
+				return(rcvchar());
+			free(hostbuf);
+			hostbuf = hostbufp = nil;
+		}
+		waitio();
 	}
 }
 
 void
-eresized(int new)
+waitio(void)
 {
-	resize_flag = 1+new;
+	enum { AMOUSE, ARESIZE, AKBD, AHOST, AEND, };
+	Alt a[AEND+1] = {
+		{ mc->c, &mouse, CHANRCV },
+		{ mc->resizec, nil, CHANRCV },
+		{ kc->c, &kbdchar, CHANRCV },
+		{ hc, &hostbuf, CHANNOP },
+		{ nil, nil, CHANEND },
+	};
+
+	if(hostbuf == nil) a[AHOST].op = CHANRCV;
+
+	curson();	/* turn on cursor while we're waiting */
+	flushimage(display, 1);
+	switch(alt(a)){
+	case AMOUSE:
+		if(button1())
+			selection();
+		else if(button2() || button3())
+			readmenu();
+		break;
+	case ARESIZE:
+		resize_flag = 2;
+		break;
+	case AHOST:
+		hostbufp = hostbuf;
+		if(hostbufp == nil){
+			close(hostfd);
+			hostfd = -1;
+		}
+		break;
+	}
+	cursoff();	/* turn cursor back off */
 }
 
 void
@@ -620,7 +670,6 @@ resize(void)
 		fprint(2, "can't reattach to window: %r\n");
 		exits("can't reattach to window");
 	}
-	draw(screen, screen->r, bgcolor, nil, ZP);
 	xmax = (Dx(screen->r) - 2*INSET)/CW-1;
 	ymax = (Dy(screen->r) - 2*INSET)/NS-1;
 	XMARGIN = (Dx(screen->r) - (xmax+1)*CW) / 2;
@@ -629,10 +678,11 @@ resize(void)
 	y = 0;
 	yscrmin = 0;
 	yscrmax = ymax;
-	free(onscreen);
-	onscreen = mallocz((ymax+1)*(xmax+2)*sizeof(Rune), 1);
 	olines = 0;
 	exportsize();
+	free(onscreen);
+	onscreen = mallocz((ymax+1)*(xmax+2)*sizeof(Rune), 1);
+	border(screen, screen->r, XMARGIN+YMARGIN, bgcolor, ZP);
 	clear(0,0,xmax+1,ymax+1);
 	if(resize_flag > 1)
 		backup(backc);
@@ -732,7 +782,8 @@ selection(void)
 			r.max.x = 0;
 		d = drawselection(r, ZR, red);
 		flushimage(display, 1);
-		mouse = emouse();
+		readmouse(mc);
+		mouse = mc->Mouse;
 		draw(screen, d, backup, nil, d.min);
 	} while(button1());
 	if((mouse.buttons & 07) == 5)
@@ -754,7 +805,7 @@ readmenu(void)
 		menu3.item[2] = ttystate[cs->raw].nlcr ? "nl" : "nlcr";
 		menu3.item[3] = cs->raw ? "cooked" : "raw";
 
-		switch(emenuhit(3, &mouse, &menu3)) {
+		switch(menuhit(3, mc, &menu3, nil)) {
 		case 0:		/* 24x80 */
 			setdim(24, 80);
 			return;
@@ -775,7 +826,7 @@ readmenu(void)
 
 	menu2.item[5] = pagemode? "scroll": "page";
 
-	switch(emenuhit(2, &mouse, &menu2)) {
+	switch(menuhit(2, mc, &menu2, nil)) {
 
 	case 0:		/* back up */
 		if(atend == 0) {
@@ -798,7 +849,7 @@ readmenu(void)
 		return;
 
 	case 3:		/* clear screen */
-		eresized(0);
+		resize_flag = 1;
 		return;
 
 	case 4:		/* send the snarf buffer */
@@ -808,7 +859,7 @@ readmenu(void)
 	case 5:		/* pause and clear at end of screen */
 		pagemode = 1-pagemode;
 		if(blocked && !pagemode) {
-			eresized(0);
+			resize_flag = 1;
 			blocked = 0;
 		}
 		return;
@@ -821,7 +872,7 @@ backup(int count)
 	Rune *cp;
 	int n;
 
-	eresized(0);
+	resize_flag = 1;
 	if(count == 0 && !pagemode) {
 		n = ymax;
 		nbacklines = HISTSIZ;	/* make sure we scroll to the very end */
@@ -927,12 +978,11 @@ number(Rune *p, int *got)
 void
 sendnchars(int n,char *p)
 {
-	if(write(outfd,p,n) < 0) {
-		close(outfd);
-		close(0);
-		close(1);
-		close(2);
-		exits("write");
+	if(hostfd < 0)
+		return;
+	if(write(hostfd,p,n) < 0){
+		close(hostfd);
+		hostfd = -1;
 	}
 }
 
@@ -941,9 +991,7 @@ host_avail(void)
 {
 	if(*echop != 0 && fullrune(echop, strlen(echop)))
 		return 1;
-	if((hostp - host_buf) < hostlength)
-		return fullrune(hostp, hostlength - (hostp - host_buf));
-	return 0;
+	return hostbufp != nil && *hostbufp != 0;
 }
 
 int
@@ -959,24 +1007,7 @@ rcvchar(void)
 		}
 		return r;
 	}
-	hostp += chartorune(&r, hostp);
-	return r;
-}
-
-void
-set_host(Event *e)
-{
-	hostlength -= (hostp - host_buf);
-	if(hostlength > 0)
-		memmove(host_buf, hostp, hostlength);
-	hostlength += e->n;
-	if(hostlength >= host_bsize) {
-		host_bsize = BSIZE*((hostlength + BSIZE)/BSIZE);
-		host_buf = realloc(host_buf, host_bsize);
-	}
-	memmove(host_buf + hostlength - e->n, e->data, e->n);
-	host_buf[hostlength] = 0;
-	hostp = host_buf;
+	return *hostbufp++;
 }
 
 void
diff --git a/sys/src/cmd/vt/mkfile b/sys/src/cmd/vt/mkfile
index 98001569c..b3a4174e2 100644
--- a/sys/src/cmd/vt/mkfile
+++ b/sys/src/cmd/vt/mkfile
@@ -4,7 +4,6 @@ TARG=vt
 
 OFILES=\
 	consctl.$O\
-	event.$O\
 	main.$O\
 	vt.$O\