From e3746662f6e2b79fe6cb18fc1f6d01334e14ad5e Mon Sep 17 00:00:00 2001
From: David du Colombier <0intro@gmail.com>
Date: Tue, 1 Jun 1993 00:00:00 +0000
Subject: [PATCH] Plan 9 from Bell Labs 1993-06-01

---
 boot/boot.c    |  13 +++
 port/devcons.c | 262 ++++++++++++++++++-------------------------------
 port/devpipe.c |   4 +-
 port/portdat.h |  37 +------
 port/portfns.h |  21 ++--
 port/qio.c     |  42 ++++++--
 6 files changed, 153 insertions(+), 226 deletions(-)

diff --git a/boot/boot.c b/boot/boot.c
index db5d477f11534bef2ace30e1045d4111b1d4d039..31f02f0c94dff0d280169c2f7472647a8f3167c8 100644
--- a/boot/boot.c
+++ b/boot/boot.c
@@ -24,6 +24,18 @@ static void	swapproc(void);
 static void	recover(Method*);
 static Method	*rootserver(char*);
 
+void
+intest(void)
+{
+	int n;
+	char buf[128];
+
+	print(">");
+	n = read(0, buf, sizeof(buf)-1);
+print("read %d bytes\n", n);
+	write(1, buf, n);
+}
+
 void
 pipetest(void)
 {
@@ -178,6 +190,7 @@ boot(int argc, char *argv[])
 	print("\n");
 #endif DEBUG
 
+	intest();
 	pipetest();
 	pipetest2();
 	ethertest();
diff --git a/port/devcons.c b/port/devcons.c
index ea1c3dd14eaf00463a4fd9b6cc680e89f07641ec..0c90b337db68d3236498604f2bcf0a94f7d78de7 100644
--- a/port/devcons.c
+++ b/port/devcons.c
@@ -8,35 +8,34 @@
 
 #include	"devtab.h"
 
-struct {
-	IOQ;			/* lock to klogputs */
-	QLock;			/* qlock to getc */
-}klogq;
+Queue	*mouseq;
+Queue	*kbdq;		/* unprocessed console input */
+Queue	*lineq;		/* processed console input */
+Queue	*printq;	/* console output */
+Queue	*klogq;
 
-IOQ	mouseq;
-IOQ	lineq;			/* lock to getc; interrupt putc's */
-IOQ	printq;
-KIOQ	kbdq;
+static struct
+{
+	QLock;
+
+	int	raw;		/* true if we shouldn't process input */
+	int	ctl;		/* number of opens to the control file */
+	int	x;		/* index into line */
+	char	line[1024];	/* current input line */
+
+	char	c;
+	int	count;
+	int	repeat;
+} kbd;
 
-static Ref	ctl;		/* number of opens to the control file */
-static int	raw;		/* true if ctl file is raw */
 
 char	sysname[NAMELEN];
 
-/*
- *  init the queues and set the output routine
- */
 void
 printinit(void)
 {
-	initq(&printq);
-	printq.puts = 0;
-	initq(&lineq);
-	initq(&kbdq);
-	kbdq.putc = kbdputc;
-	initq(&klogq);
-	initq(&mouseq);
-	mouseq.putc = mouseputc;
+	klogq = qopen(32*1024, 0, 0, 0);
+	lineq = qopen(2*1024, 0, 0, 0);
 }
 
 /*
@@ -65,7 +64,7 @@ putstrn(char *str, int n)
 	 *  put the message there.  Tack a carriage return
 	 *  before new lines.
 	 */
-	if(printq.puts == 0)
+	if(printq == 0)
 		return;
 	while(n > 0){
 		t = memchr(str, '\n', n);
@@ -74,62 +73,16 @@ putstrn(char *str, int n)
 			memmove(buf, str, m);
 			buf[m] = '\r';
 			buf[m+1] = '\n';
-			(*printq.puts)(&printq, buf, m+2);
+			qwrite(printq, buf, m+2, 1);
 			str = t + 1;
 			n -= m + 1;
 		} else {
-			(*printq.puts)(&printq, str, n);
+			qwrite(printq, str, n, 1);
 			break;
 		}
 	}
 }
 
-/*
- *   Print a string in the kernel log.  Ignore overflow.
- */
-void
-klogputs(char *str, long n)
-{
-	int s, m;
-	uchar *nextin;
-
-	s = splhi();
-	lock(&klogq);
-	while(n){
-		m = &klogq.buf[NQ] - klogq.in;
-		if(m > n)
-			m = n;
-		memmove(klogq.in, str, m);
-		n -= m;
-		str += m;
-		nextin = klogq.in + m;
-		if(nextin >= &klogq.buf[NQ])
-			klogq.in = klogq.buf;
-		else
-			klogq.in = nextin;
-	}
-	unlock(&klogq);
-	splx(s);
-	wakeup(&klogq.r);
-}
-
-int
-isbrkc(KIOQ *q)
-{
-	uchar *p;
-
-	for(p=q->out; p!=q->in; ){
-		if(raw)
-			return 1;
-		if(*p==0x04 || *p=='\n')
-			return 1;
-		p++;
-		if(p >= q->buf+sizeof(q->buf))
-			p = q->buf;
-	}
-	return 0;
-}
-
 int
 sprint(char *s, char *fmt, ...)
 {
@@ -154,7 +107,7 @@ kprint(char *fmt, ...)
 	int n;
 
 	n = doprint(buf, buf+sizeof(buf), fmt, (&fmt+1)) - buf;
-	klogputs(buf, n);
+	qwrite(klogq, buf, n, 1);
 	return n;
 }
 
@@ -202,7 +155,7 @@ pprint(char *fmt, ...)
 void
 prflush(void)
 {
-	while(printq.in != printq.out) ;
+	while(qlen(printq) > 0) ;
 }
 
 void
@@ -245,8 +198,12 @@ echo(Rune r, char *buf, int n)
 		return;
 	}
 	ctrlt = 0;
-	if(raw)
+	if(kbd.raw)
 		return;
+
+	/*
+	 *  finally, the actual echoing
+	 */
 	if(r == 0x15)
 		putstrn("^U\n", 3);
 	else
@@ -254,10 +211,12 @@ echo(Rune r, char *buf, int n)
 }
 
 /*
- *  turn '\r' into '\n' before putting it into the queue
+ *  Called by a uart interrupt for console input.
+ *
+ *  turn '\r' into '\n' before putting it into the queue.
  */
 int
-kbdcr2nl(IOQ *q, int ch)
+kbdcr2nl(Queue *q, int ch)
 {
 	if(ch == '\r')
 		ch = '\n';
@@ -267,11 +226,13 @@ kbdcr2nl(IOQ *q, int ch)
 /*
  *  Put character, possibly a rune, into read queue at interrupt time.
  *  Always called splhi from processor 0.
+ *
+ *  Called at interrupt time to process a character.
  */
 int
-kbdputc(IOQ *q, int ch)
+kbdputc(Queue *q, int ch)
 {
-	int i, n;
+	int n;
 	char buf[3];
 	Rune r;
 
@@ -281,42 +242,35 @@ kbdputc(IOQ *q, int ch)
 	if(n == 0)
 		return 0;
 	echo(r, buf, n);
-	kbdq.c = r;
-	for(i=0; i<n; i++){
-		*kbdq.in++ = buf[i];
-		if(kbdq.in == kbdq.buf+sizeof(kbdq.buf))
-			kbdq.in = kbdq.buf;
-	}
-	if(raw || r=='\n' || r==0x04)
-		wakeup(&kbdq.r);
+	qproduce(kbdq, buf, n);
 	return 0;
 }
 
 void
 kbdrepeat(int rep)
 {
-	kbdq.repeat = rep;
-	kbdq.count = 0;
+	kbd.repeat = rep;
+	kbd.count = 0;
 }
 
 void
 kbdclock(void)
 {
-	if(kbdq.repeat == 0)
+	if(kbd.repeat == 0)
 		return;
-	if(kbdq.repeat==1 && ++kbdq.count>HZ){
-		kbdq.repeat = 2;
-		kbdq.count = 0;
+	if(kbd.repeat==1 && ++kbd.count>HZ){
+		kbd.repeat = 2;
+		kbd.count = 0;
 		return;
 	}
-	if(++kbdq.count&1)
-		kbdputc(&kbdq, kbdq.c);
+	if(++kbd.count&1)
+		kbdputc(kbdq, kbd.c);
 }
 
 int
 consactive(void)
 {
-	return printq.in != printq.out;
+	return qlen(printq) > 0;
 }
 
 enum{
@@ -456,7 +410,9 @@ consopen(Chan *c, int omode)
 	case Qconsctl:
 		if(!iseve())
 			error(Eperm);
-		incref(&ctl);
+		qlock(&kbd);
+		kbd.ctl++;
+		qunlock(&kbd);
 		break;
 	}
 	return devopen(c, omode, consdir, NCONS, devgen);
@@ -476,10 +432,10 @@ consclose(Chan *c)
 	switch(c->qid.path){
 	case Qconsctl:
 		if(c->flag&COPEN){
-			lock(&ctl);
-			if(--ctl.ref == 0)
-				raw = 0;
-			unlock(&ctl);
+			qlock(&kbd);
+			if(--kbd.ctl == 0)
+				kbd.raw = 0;
+			qunlock(&kbd);
 		}
 	case Qauth:
 	case Qauthcheck:
@@ -504,52 +460,41 @@ consread(Chan *c, void *buf, long n, ulong offset)
 		return devdirread(c, buf, n, consdir, NCONS, devgen);
 
 	case Qcons:
-		qlock(&kbdq);
+		qlock(&kbd);
 		if(waserror()){
-			qunlock(&kbdq);
+			qunlock(&kbd);
 			nexterror();
 		}
-		while(!cangetc(&lineq)){
-			sleep(&kbdq.r, isbrkc, &kbdq);
-			do{
-				lock(&lineq);
-				ch = getc(&kbdq);
-				if(raw)
-					goto Default;
-				switch(ch){
-				case '\b':
-					if(lineq.in != lineq.out){
-						if(lineq.in == lineq.buf)
-							lineq.in = lineq.buf+sizeof(lineq.buf);
-						lineq.in--;
-					}
-					break;
-				case 0x15:
-					lineq.in = lineq.out;
-					break;
-				Default:
-				default:
-					*lineq.in = ch;
-					if(lineq.in >= lineq.buf+sizeof(lineq.buf)-1)
-						lineq.in = lineq.buf;
-					else
-						lineq.in++;
-				}
-				unlock(&lineq);
-			}while(raw==0 && ch!='\n' && ch!=0x04);
-		}
-		i = 0;
-		while(n > 0){
-			ch = getc(&lineq);
-			if(ch==-1 || (raw==0 && ch==0x04))
+		while(!qcanread(lineq)){
+			qread(kbdq, &kbd.line[kbd.x], 1);
+			ch = kbd.line[kbd.x];
+			if(kbd.raw){
+				i = splhi();
+				qproduce(lineq, &kbd.line[kbd.x], 1);
+				splx(i);
+				continue;
+			}
+			switch(ch){
+			case '\b':
+				if(kbd.x)
+					kbd.x--;
+				break;
+			case 0x15:
+				kbd.x = 0;
+				break;
+			default:
+				kbd.line[kbd.x++] = ch;
 				break;
-			i++;
-			*cbuf++ = ch;
-			--n;
+			}
+			if(kbd.x == sizeof(kbd.line) || ch == '\n' || ch == 0x04){
+				if(ch == 0x04)
+					kbd.x--;
+				qwrite(lineq, kbd.line, kbd.x, 1);
+			}
 		}
-		poperror();
-		qunlock(&kbdq);
-		return i;
+		n = qread(lineq, buf, n);
+		qunlock(&kbd);
+		return n;
 
 	case Qcputime:
 		k = offset;
@@ -613,21 +558,7 @@ consread(Chan *c, void *buf, long n, ulong offset)
 		return 0;
 
 	case Qklog:
-		qlock(&klogq);
-		if(waserror()){
-			qunlock(&klogq);
-			nexterror();
-		}
-		while(!cangetc(&klogq))
-			sleep(&klogq.r, cangetc, &klogq);
-		for(i=0; i<n; i++){
-			if((ch=getc(&klogq)) == -1)
-				break;
-			*cbuf++ = ch;
-		}
-		poperror();
-		qunlock(&klogq);
-		return i;
+		return qread(klogq, buf, n);
 
 	case Qmsec:
 		return readnum(offset, buf, n, TK2MS(MACHP(0)->ticks), NUMSIZE);
@@ -730,7 +661,7 @@ conswrite(Chan *c, void *va, long n, ulong offset)
 	long l, bp;
 	char *a = va;
 	Mach *mp;
-	int id, fd, ch;
+	int id, fd;
 	Chan *swc;
 
 	switch(c->qid.path){
@@ -757,20 +688,15 @@ conswrite(Chan *c, void *va, long n, ulong offset)
 		buf[n] = 0;
 		for(a = buf; a;){
 			if(strncmp(a, "rawon", 5) == 0){
-				lock(&lineq);
-				while((ch=getc(&kbdq)) != -1){
-					*lineq.in++ = ch;
-					if(lineq.in == lineq.buf+sizeof(lineq.buf))
-						lineq.in = lineq.buf;
+				qlock(&kbd);
+				if(kbd.x){
+					qwrite(kbdq, kbd.line, kbd.x, 1);
+					kbd.x = 0;
 				}
-				unlock(&lineq);
-				lock(&ctl);
-				raw = 1;
-				unlock(&ctl);
+				kbd.raw = 1;
+				qunlock(&kbd);
 			} else if(strncmp(a, "rawoff", 6) == 0){
-				lock(&ctl);
-				raw = 0;
-				unlock(&ctl);
+				kbd.raw = 0;
 			}
 			if(a = strchr(a, ' '))
 				a++;
diff --git a/port/devpipe.c b/port/devpipe.c
index c1f1521c48b3a5a9227676643484ac8d16ed6161..4193ae6201282c1e433d7a7e9684915ffa843d5c 100644
--- a/port/devpipe.c
+++ b/port/devpipe.c
@@ -301,9 +301,9 @@ pipewrite(Chan *c, void *va, long n, ulong offset)
 
 	switch(NETTYPE(c->qid.path)){
 	case Qdata0:
-		return qwrite(p->q[1], va, n);
+		return qwrite(p->q[1], va, n, 0);
 	case Qdata1:
-		return qwrite(p->q[0], va, n);
+		return qwrite(p->q[0], va, n, 0);
 	default:
 		panic("piperead");
 	}
diff --git a/port/portdat.h b/port/portdat.h
index 51085e68c9c061d4940496f9580b7f2ccaf0dcef..ebd998d7f63ef666f089e78720182fd42f58ea73 100644
--- a/port/portdat.h
+++ b/port/portdat.h
@@ -218,36 +218,6 @@ struct Scsi
 	uchar		cmdblk[16];
 };
 
-/* character based IO (mouse, keyboard, console screen) */
-#define NQ	4096
-struct IOQ
-{
-	Lock;
-	uchar	buf[NQ];
-	uchar	*in;
-	uchar	*out;
-	int	state;
-	Rendez	r;
-	union{
-		void	(*puts)(IOQ*, void*, int);	/* output */
-		int	(*putc)(IOQ*, int);		/* input */
-	};
-	union{
-		int	(*gets)(IOQ*, void*, int);	/* input */
-		int	(*getc)(IOQ*);			/* output */
-	};
-	void	*ptr;
-};
-
-struct KIOQ
-{
-	QLock;
-	IOQ;
-	int	repeat;
-	int	c;
-	int	count;
-};
-
 enum
 {
 	NSMAX	=	1000,
@@ -654,13 +624,12 @@ extern  char	eve[];
 extern	char	hostdomain[];
 extern	uchar	initcode[];
 extern	FPsave	initfp;
-extern  KIOQ	kbdq;
-extern  IOQ	lineq;
-extern  IOQ	mouseq;
+extern  Queue	*kbdq;
+extern  Queue	*mouseq;
 extern  Ref	noteidalloc;
 extern	int	nrdy;
 extern	Palloc	palloc;
-extern  IOQ	printq;
+extern  Queue	*printq;
 extern	char*	statename[];
 extern  Image	swapimage;
 extern	char	sysname[NAMELEN];
diff --git a/port/portfns.h b/port/portfns.h
index 7fd1bb151262286a7dd0d5462c1b61d5fae712ff..eb651470edfbaabd298e6e0f02f37f64ac0b1b57 100644
--- a/port/portfns.h
+++ b/port/portfns.h
@@ -77,10 +77,8 @@ void		freechan(Chan*);
 void		freepte(Segment*, Pte*);
 void		freesegs(int);
 void		freesession(Session*);
-int		getc(IOQ*);
 void		getcolor(ulong, ulong*, ulong*, ulong*);
 int		getfields(char*, char**, int, char);
-int		gets(IOQ*, void*, int);
 void		gotolabel(Label*);
 int		haswaitq(void*);
 int		hwcursmove(int, int);
@@ -88,15 +86,14 @@ int		hwcursset(uchar*, uchar*, int, int);
 void		iallocinit(void);
 long		ibrk(ulong, int);
 int		incref(Ref*);
-void		initq(IOQ*);
 void		initscsi(void);
 void		initseg(void);
 void		invalidateu(void);
 void		isdir(Chan*);
 int		ispages(void*);
 void		kbdclock(void);
-int		kbdcr2nl(IOQ*, int);
-int		kbdputc(IOQ*, int);
+int		kbdcr2nl(Queue*, int);
+int		kbdputc(Queue*, int);
 void		kbdrepeat(int);
 void		kickpager(void);
 int		kprint(char*, ...);
@@ -109,7 +106,6 @@ void		lights(int);
 void		lock(Lock*);
 void		lockinit(void);
 Page*		lookpage(Image*, ulong);
-int		m3mouseputc(IOQ*, int);
 void		machinit(void);
 void*		malloc(ulong);
 void		mmuswitch(Proc*);
@@ -123,7 +119,6 @@ void		mountfree(Mount*);
 void		mousebuttons(int);
 void		mousectl(char*);
 void		mouseclock(void);
-int		mouseputc(IOQ*, int);
 void		mousescreenupdate(void);
 int		msize(void*);
 Chan*		namec(char*, int, int, ulong);
@@ -159,28 +154,27 @@ void		procinit0(void);
 Proc*		proctab(int);
 Pte*		ptealloc(void);
 Pte*		ptecpy(Pte*);
-int		putc(IOQ*, int);
 void		putimage(Image*);
 void		putmmu(ulong, ulong, Page*);
 void		putpage(Page*);
-void		puts(IOQ*, void*, int);
 void		putseg(Segment*);
 void		putstr(char*);
 void		putstr(char*);
 void		putstrn(char*, long);
 void		putswap(Page*);
 ulong		pwait(Waitmsg*);
+int		qcanread(Queue*);
 void		qclose(Queue*);
-int		qconsume(Queue*, uchar*, int);
+int		qconsume(Queue*, void*, int);
 void		qhangup(Queue*);
 int		qlen(Queue*);
 void		qlock(QLock*);
 Queue*		qopen(int, int, void (*)(void*), void*);
-int		qproduce(Queue*, uchar*, int);
-long		qread(Queue*, char*, int);
+int		qproduce(Queue*, void*, int);
+long		qread(Queue*, void*, int);
 void		qreopen(Queue*);
 void		qunlock(QLock*);
-long		qwrite(Queue*, char*, int);
+long		qwrite(Queue*, void*, int, int);
 int		readnum(ulong, char*, ulong, ulong, int);
 int		readstr(ulong, char*, ulong, char*);
 void		ready(Proc*);
@@ -197,7 +191,6 @@ void		savefpregs(FPsave*);
 void		sccclock(void);
 int		sccintr(void);
 void		sccsetup(void*, ulong, int);
-void		sccspecial(int, IOQ*, IOQ*, int);
 void		sched(void);
 void		schedinit(void);
 int		screenbits(void);
diff --git a/port/qio.c b/port/qio.c
index 119a7528a2d5c0da4deb801304302918185c0391..dc3c2d27a8ad181e3dcb169ae2d1fcc0e9b696f7 100644
--- a/port/qio.c
+++ b/port/qio.c
@@ -253,10 +253,11 @@ allocb(int size)
  *  set, any bytes left in a block afer a consume are discarded.
  */
 int
-qconsume(Queue *q, uchar *p, int len)
+qconsume(Queue *q, void *vp, int len)
 {
 	Block *b;
 	int n, dowakeup;
+	uchar *p = vp;
 
 	/* sync with qwrite */
 	lock(q);
@@ -298,10 +299,11 @@ qconsume(Queue *q, uchar *p, int len)
 }
 
 int
-qproduce(Queue *q, uchar *p, int len)
+qproduce(Queue *q, void *vp, int len)
 {
 	Block *b;
 	int dowakeup;
+	uchar *p = vp;
 
 	/* sync with qread */
 	lock(q);
@@ -340,8 +342,11 @@ qproduce(Queue *q, uchar *p, int len)
 		dowakeup = 0;
 	unlock(q);
 
-	if(dowakeup)
+	if(dowakeup){
+		if(q->kick)
+			(*q->kick)(q->arg);
 		wakeup(&q->rr);
+	}
 
 	return len;
 }
@@ -363,6 +368,7 @@ qopen(int limit, int msg, void (*kick)(void*), void *arg)
 	q->kick = kick;
 	q->arg = arg;
 	q->state = msg ? Qmsg : 0;
+	q->state |= Qstarve;
 
 	return q;
 }
@@ -380,10 +386,11 @@ notempty(void *a)
  *  and wait on its Rendez.
  */
 long
-qread(Queue *q, char *p, int len)
+qread(Queue *q, void *vp, int len)
 {
 	Block *b;
 	int x, n, dowakeup;
+	uchar *p = vp;
 
 	qlock(&q->rlock);
 	if(waserror()){
@@ -467,10 +474,11 @@ qnotfull(void *a)
  *  queue the data.
  */
 long
-qwrite(Queue *q, char *p, int len)
+qwrite(Queue *q, void *vp, int len, int nowait)
 {
 	int x, dowakeup;
 	Block *b;
+	uchar *p = vp;
 
 	b = allocb(len);
 	memmove(b->wp, p, len);
@@ -478,6 +486,8 @@ qwrite(Queue *q, char *p, int len)
 
 	/* flow control */
 	while(!qnotfull(q)){
+		if(nowait)
+			return len;
 		qlock(&q->wlock);
 		q->state |= Qflow;
 		sleep(&q->wr, qnotfull, q);
@@ -493,8 +503,11 @@ qwrite(Queue *q, char *p, int len)
 		error(Ehungup);
 	}
 
-	b->next = q->bfirst;
-	q->bfirst = b;
+	if(q->bfirst)
+		q->blast->next = b;
+	else
+		q->bfirst = b;
+	q->blast = b;
 	q->len += len;
 
 	if(q->state & Qstarve){
@@ -506,8 +519,11 @@ qwrite(Queue *q, char *p, int len)
 	unlock(q);
 	splx(x);
 
-	if(dowakeup)
+	if(dowakeup){
+		if(q->kick)
+			(*q->kick)(q->arg);
 		wakeup(&q->rr);
+	}
 
 	return len;
 }
@@ -570,6 +586,7 @@ void
 qreopen(Queue *q)
 {
 	q->state &= ~Qclosed;
+	q->state |= Qstarve;
 }
 
 /*
@@ -580,3 +597,12 @@ qlen(Queue *q)
 {
 	return q->len;
 }
+
+/*
+ *  return true if we can read without blocking
+ */
+int
+qcanread(Queue *q)
+{
+	return q->bfirst!=0;
+}