allow arrow keys to work on console or rio window; but since there's no
way to position the cursor without erasing text ← and ^a don't work
as one would expect.  (this could be fixed, but norio itself seems a bit
misguided) 

additionally, fix rune handling.  ironicly vt can't handle this.

Reference: /n/atom/patch/applied2013/noriofixes
Date: Thu Dec 26 13:55:10 CET 2013
Signed-off-by: quanstro@quanstro.net

--- /sys/src/cmd/aux/norio.c	Thu Dec 26 13:52:06 2013
+++ /sys/src/cmd/aux/norio.c	Thu Dec 26 13:52:07 2013
@@ -3,8 +3,10 @@
 #include <fcall.h>
 #include <thread.h>
 #include <9p.h>
+#include <keyboard.h>
 
 #define Ctl(c)	((c) - '@')
+#define Esc(c)	((c) << 24)
 
 enum {
 	Hbufsz	= 8192,
@@ -333,7 +335,7 @@
 	char *e, *p;
 
 	if(h->histfd == -1)
-		return nil;
+		return "";
 	if(h->reset == 1){
 		dohistreset(h);
 		h->reset = 0;
@@ -356,7 +358,7 @@
 		}
 		if(histfil(h, 1) == -1){
 			h->dir = 0;
-			return nil;
+			return "";
 		}
 	}
 }
@@ -388,6 +390,27 @@
 }
 
 int
+cpnrune(char *s1, char *s2, int n)
+{
+	int rv, m;
+	Rune dummy;
+
+	rv = 0;
+	for(;n > 0; n--){
+		if(*s2 == 0){
+			rv = -1;
+			break;
+		}
+		m = chartorune(&dummy, s2);
+		memcpy(s1, s2, m);	
+		s1 += m;
+		s2 += m;
+	}
+	*s1 = 0;
+	return rv;
+}
+
+int
 countrunes(char *s, char *e)
 {
 	int i, n;
@@ -424,7 +447,8 @@
 	if(n == 0)
 		return -1;
 	i->tick += n;
-	return n < 0? 1: 3;
+//	return n < 0? 1: 3;
+	return 3;
 }
 
 int
@@ -527,8 +551,9 @@
 	c->outpt += n;
 }
 
+/* esc sequences from ansi terminals */
 int
-ichar(Cp *p, int c)
+irune(Cp *p, Rune c)
 {
 	char *t, *tl, *rp, *s, *o, buf[256*4], tbuf[512];
 	int r, i, n, rv, esc, emit;
@@ -537,8 +562,7 @@
 	cn = p->cons;
 	emit = 3;
 	r = cn->raw;
-	buf[0] = c;
-	buf[1] = 0;
+	snprint(buf, sizeof buf, "%C", c);
 	s = o = buf;
 	tl = nil;
 	rv = 1;
@@ -558,17 +582,17 @@
 		esc = 0;
 		if(s == nil)
 			r = 1;
-		else switch(cn->esc << 8 | c){
-		case 1<<8 | '[':
-		case 1<<8 | 'O':
+		else switch(Esc(cn->esc) | c){
+		case Esc(1) | '[':
+		case Esc(1) | 'O':
 			esc = 2;
 			emit = 0;
 			break;
-		case 2<<8 | '3':
+		case Esc(2) | '3':
 			esc = 3;
 			emit = 0;
 			break;
-		case 3<<8 | '~':
+		case Esc(3) | '~':
 			if(cn->tick == cn->e){
 				emit = 0;
 				break;
@@ -579,7 +603,8 @@
 			o = "";
 			tl = " \b";
 			break;
-		case 2<<8 | 'A':
+		case Kup:
+		case Esc(2) | 'A':
 		case Ctl('P'):
 			s = hprev(cn);
 			if(s == nil)
@@ -600,39 +625,34 @@
 			cleanibuf(cn);
 			addstr(cn, s);
 			break;
-		case 2<<8 | 'B':
+		case Kdown:
+		case Esc(2) | 'B':
 		case Ctl('N'):
 			s = hnext(cn);
-			if(s == nil)
-				s = "";
 			goto h;
-		case 2<<8 | 'C':
+		case Kright:
+		case Esc(2) | 'C':
 		case Ctl('F'):
-			buf[0] = cn->tick[0];
-			buf[1] = 0;
+			cpnrune(buf, cn->tick, 1);
 			emit = move(cn, 1);
 			o = buf;
 			break;
-		case 2<<8 | 'D':
+		case Kleft:
+		case Esc(2) | 'D':
 		case Ctl('B'):
 			emit = move(cn, -1);
 			o = "\b";
 			break;
 		case Ctl('A'):
 			n = cn->tick-cn->ibuf;
-			for(i = 0; i < n;)
-				buf[i++] = Ctl('H');
-			buf[i] = 0;
+			memset(buf, Ctl('H'), n);
+			buf[n] = 0;
 			s = buf;
 			cn->tick = cn->ibuf;
 			emit = 1;
 			break;
 		case 0x7f:
 		case Ctl('C'):
-	//		proccreate(interruptproc, cn, 4096);
-	//		o = "";
-	//		s = nil;
-	//		break;
 			interruptproc(cn);
 			if(sendp(p->c, nil) == -1)
 				sysfatal("sendp: %r");
@@ -656,7 +676,7 @@
 			n = cn->e - cn->tick;
 			cut(cn, cn->tick, n);
 			memset(buf, ' ', n);
-			memset(buf+n, '\b', n);
+			memset(buf+n, '\b', n);		/* wrong, runes */
 			buf[2*n] = 0;
 			s = buf;
 			cn->e = cn->tick;
@@ -737,22 +757,40 @@
 		cn->e[0] = 0;
 		if(r != 1 && emit&2 && cn->tick != cn->e){
 			emitit(cn->co, cn->tick);
-			n = cn->e - cn->tick;
-			for(i = 0; i < n;)
-				buf[i++] = Ctl('H');
-			buf[i] = 0;
+			n = countrunes(cn->tick, cn->e);
+			memset(buf, Ctl('H'), n);
+			buf[n] = 0;
 			rp = buf;
 		}
 		if(tl != nil)
 			emitit(cn->co, tl);
 		if(rp != nil)
-			emitit(cn->co, buf);
+			emitit(cn->co, rp);
 	}
 	if(r)
 		cleanibuf(cn);
 	return rv;
 }
 
+int
+ichar(Cp *p, int c)
+{
+	Rune r;
+	static char rbuf[UTFmax+1];
+	static int i;
+
+	if(i == UTFmax)
+		i = 0;
+	rbuf[i++] = c;
+	if(!fullrune(rbuf, i))
+		return 1;
+	i = 0;
+	chartorune(&r, rbuf);
+	if(r != Runeerror)
+		return irune(p, r);
+	return 1;
+}
+
 void
 consiproc(void *v)
 {
@@ -777,7 +815,7 @@
 	dump:;
 	}
 dead:
-syslog(0, "norio", "%s exiting %s", buf, "dead");
+//	syslog(0, "norio", "%s exiting %s", buf, "dead");
 fprint(2, "%s: exiting\n", buf);
 	chanclose(c->c);
 	threadexitsall("");
@@ -802,8 +840,8 @@
 		if(n == -1)
 			break;
 	}
-syslog(0, "norio", "%s exiting %s", buf, s);
-fprint(2, "%s: exiting\n", buf);
+//	syslog(0, "norio", "%s exiting %s", buf, s);
+fprint(2, "%s: exiting %s\n", buf, s);
 	chanclose(c->c);
 	threadexits("");
 }
@@ -1055,6 +1093,7 @@
 		return;
 	}
 
+//	r->fid->aux = a;
 	switch(a->type){
 	default:
 		abort();
@@ -1071,7 +1110,6 @@
 		respond(r, nil);
 		break;
 	}
-	r->fid->aux = a;
 }
 
 void
@@ -1156,7 +1194,7 @@
 void
 usage(void)
 {
-	fprint(2, "usage: norio [Ssml]\n");
+	fprint(2, "usage: norio [-Sl] [-s srvpt] [-m mtpt]\n");
 	exits("");
 }
 
@@ -1192,7 +1230,7 @@
 	if(!flag['l']){
 		c->ctlfd = open(consctl, OWRITE);
 		if(c->ctlfd == -1)
-		sysfatal("open: %r");
+			sysfatal("open: %r");
 		write(c->ctlfd, "rawon", 5);
 	}
 
@@ -1216,14 +1254,12 @@
 	threadpostmountsrv(&fs, srv, mtpt, MBEFORE);
 	c->pid = rc();
 	threadnotify(nf0, 1);
-//	while(waitpid() != c->pid)
-//		;
 	for(;;){
 		w = wait();
 		if(w == nil)
 			break;
 		if(w->msg && w->msg[0])
-			print("rc exits: %s\n", w->msg);
+			fprint(2, "rc exits: %s\n", w->msg);
 		free(w);
 		break;
 	}