10 files changed, 166 insertions(+), 81 deletions(-)

M gnot/errno.h
A pc/cga.c
M pc/trap.c
M pc/vga.c
M port/devproc.c
M port/portdat.h
M port/segment.c
M port/sysproc.c
M power/errno.h
M ss/trap.c

@@ 1,5 1,5 @@
 enum{
-	Enevermind,	/* never mind */
+	Enoerror,	/* no error */
 	Enofd,		/* no free file descriptors */
 	Ebadfd,		/* fd out of range or not open */
 	Ebadusefd,	/* inappropriate use of fd */

@@ 0,0 1,58 @@
+#include	"u.h"
+#include	"lib.h"
+#include	"mem.h"
+#include	"dat.h"
+#include	"fns.h"
+
+#define	WIDTH	160
+#define	HEIGHT	24
+#define SCREEN	((char *)(0xB8000|KZERO))
+int pos;
+
+void
+screeninit(void)
+{
+	memset(SCREEN+pos, 0, WIDTH*HEIGHT-pos);
+}
+
+void
+screenputc(int c)
+{
+	int i;
+	static int color;
+
+	if(c == '\n'){
+		pos = pos/WIDTH;
+		pos = (pos+1)*WIDTH;
+	} else if(c == '\t'){
+		i = 8 - ((pos/2)&7);
+		while(i-->0)
+			screenputc(' ');
+	} else if(c == '\b'){
+		if(pos >= 2)
+			pos -= 2;
+		screenputc(' ');
+		pos -= 2;
+	} else {
+		SCREEN[pos++] = c;
+		SCREEN[pos++] = 0x1d;
+	}
+	if(pos >= WIDTH*HEIGHT){
+		memmove(SCREEN, &SCREEN[WIDTH], WIDTH*(HEIGHT-1));
+		memset(&SCREEN[WIDTH*(HEIGHT-1)], 0, WIDTH);
+		pos = WIDTH*(HEIGHT-1);
+	}
+}
+
+void
+screenputs(char *s, int n)
+{
+	while(n-- > 0)
+		screenputc(*s++);
+}
+
+int
+screenbits(void)
+{
+	return 4;
+}

@@ 259,7 259,7 @@ syscall(Ureg *ur)
 	if(ax == NOTED){
 		noted(ur, *(ulong*)(sp+BY2WD));
 		ret = -1;
-	} else if(u->nnote){
+	} else if(u->nnote && ax!=FORK){
 		ur->ax = ret;
 		notify(ur);
 	}


@@ 346,7 346,7 @@ noted(Ureg *ur, ulong arg0)
 	u->notified = 0;
 	nur->flags = (u->svflags&0xffffff00) | (ur->flags&0xff);
 	memmove(ur, u->ureg, sizeof(Ureg));
-	ur->ax = -1;	/* return error from the interrupted call */
+	ur->ax = -1;	/* return error from the interrupted syscall */
 	switch(arg0){
 	case NCONT:
 		splhi();

@@ 9,21 9,43 @@ enum
 {
 	GRX=		0x3CE,		/* index to graphics registers */
 	GR=		0x3CF,		/* graphics registers 0-8 */
+	SRX=		0x3C4,		/* index to sequence registers */
+	SR=		0x3C5,		/* sequence registers 0-7 */
 };
 
+void
+srout(int reg, int val)
+{
+	outb(SRX, reg);
+	outb(SR, val);
+}
+
+void
+grout(int reg, int val)
+{
+	outb(GRX, reg);
+	outb(GR, val);
+}
+
 /*
  *  look at VGA registers
  */
 void
 vgainit(void)
 {
+	uchar *display;
 	int i;
-	uchar x;
 
-	for(i = 0; i < 9; i++){
-		outb(GRX, i);
-		x = inb(GR);
-		print("GR%d == %ux\n", i, x);
-	}
-	panic("for the hell of it");
+	srout(2, 0x0f);		/* enable all 4 color planes */
+	srout(4, 0x08);		/* quad mode */
+	grout(5, 0x40);		/* pixel bits are sequential */
+	grout(6, 0x01);		/* graphics mode - display starts at 0xA0000 */
+
+	for(;;);
+	display = (uchar*)(0xA0000 | KZERO);
+	for(i = 0; i < 128*1024; i++)
+		display[i] = 0x00;
+
+	for(i = 0; i < 4*640; i++)
+		display[i] = 0xff;
 }

@@ 273,7 273,7 @@ procread(Chan *c, void *va, long n, ulong offset)
 			s->steal++;
 			qunlock(&s->lk);
 			if(pagedout(pg)){
-				pprint("nonresident page addr %lux (complain to rob)\n", offset);
+				pprint("nonresident page addr %lux (complain to philw)\n", offset);
 				memset(a, 0, n);
 			}else{
 				k = kmap(pg);

@@ 63,7 63,7 @@ struct Alarm
 	List;
 	Lock;
 	int	busy;
-	long	dt;		/* may underflow in clock(); must be signed */
+	long	dt;			/* may underflow in clock(); must be signed */
 	void	(*f)(void*);
 	void	*arg;
 };


@@ 86,20 86,20 @@ struct Alarms
 struct Block
 {
 	Block	*next;
-	uchar	*rptr;		/* first unconsumed byte */
-	uchar	*wptr;		/* first empty byte */
-	uchar	*lim;		/* 1 past the end of the buffer */
-	uchar	*base;		/* start of the buffer */
+	uchar	*rptr;			/* first unconsumed byte */
+	uchar	*wptr;			/* first empty byte */
+	uchar	*lim;			/* 1 past the end of the buffer */
+	uchar	*base;			/* start of the buffer */
 	uchar	flags;
 	uchar	type;
 };
 
 struct Blist {
 	Lock;
-	Block	*first;		/* first data block */
-	Block	*last;		/* last data block */
-	long	len;		/* length of list in bytes */
-	int	nb;		/* number of blocks in list */
+	Block	*first;			/* first data block */
+	Block	*last;			/* last data block */
+	long	len;			/* length of list in bytes */
+	int	nb;			/* number of blocks in list */
 };
 
 /*


@@ 107,21 107,21 @@ struct Blist {
  */
 enum
 {
-	Aaccess,	/* as in access, stat */
-	Atodir,		/* as in chdir */
-	Aopen,		/* for i/o */
-	Amount,		/* to be mounted upon */
-	Acreate,	/* file is to be created */
+	Aaccess,			/* as in access, stat */
+	Atodir,				/* as in chdir */
+	Aopen,				/* for i/o */
+	Amount,				/* to be mounted upon */
+	Acreate,			/* file is to be created */
 };
 
 /*
  *  Chan.flags
  */
-#define	COPEN	1	/* for i/o */
-#define	CMOUNT	2	/* is result of a mount/bind */
-#define	CCREATE	4	/* permits creation if CMOUNT */
-#define	CCEXEC	8	/* close on exec */
-#define	CFREE	16	/* not in use */
+#define	COPEN	1			/* for i/o */
+#define	CMOUNT	2			/* is result of a mount/bind */
+#define	CCREATE	4			/* permits creation if CMOUNT */
+#define	CCEXEC	8			/* close on exec */
+#define	CFREE	16			/* not in use */
 
 struct Chan
 {


@@ 200,9 200,9 @@ struct Etherpkt {
 	uchar data[1500];
 	uchar crc[4];
 };
-#define	ETHERMINTU	60	/* minimum transmit size */
-#define	ETHERMAXTU	1514	/* maximum transmit size */
-#define ETHERHDRSIZE	14	/* size of an ethernet header */
+#define	ETHERMINTU	60		/* minimum transmit size */
+#define	ETHERMAXTU	1514		/* maximum transmit size */
+#define ETHERHDRSIZE	14		/* size of an ethernet header */
 
 /*
  *  character based IO (mouse, keyboard, console screen)


@@ 287,12 287,12 @@ struct Page
 
 struct Swapalloc
 {
-	Lock;			/* Free map lock */
-	int	free;		/* Number of currently free swap pages */
-	char	*swmap;		/* Base of swap map in memory */
-	char	*alloc;		/* Round robin allocator */
-	char	*top;		/* Top of swap map */
-	Rendez	r;		/* Pager kproc idle sleep */
+	Lock;				/* Free map lock */
+	int	free;			/* Number of currently free swap pages */
+	char	*swmap;			/* Base of swap map in memory */
+	char	*alloc;			/* Round robin allocator */
+	char	*top;			/* Top of swap map */
+	Rendez	r;			/* Pager kproc idle sleep */
 }swapalloc;
 
 struct Image


@@ 390,17 390,17 @@ struct Palloc
 	Lock;
 	ulong	addr;
 	int	active;
-	Page	*page;		/* base of Page structures, indexed by phys page number */
-	ulong	minppn;		/* index of first usable page */
-	Page	*head;		/* most recently used */
-	Page	*tail;		/* least recently used */
-	ulong	freecount;	/* how many pages on free list now */
-	ulong	user;		/* how many user pages */
+	Page	*page;			/* base of Page structures */
+	ulong	minppn;			/* index of first usable page */
+	Page	*head;			/* most recently used */
+	Page	*tail;			/* least recently used */
+	ulong	freecount;		/* how many pages on free list now */
+	ulong	user;			/* how many user pages */
 	Page	*hash[PGHSIZE];
 	Lock	hashlock;
-	Rendez	r;		/* Sleep for free mem */
-	QLock	pwait;		/* Queue of procs waiting for memory */
-	int	wanted;		/* Do the wakeup at free */
+	Rendez	r;			/* Sleep for free mem */
+	QLock	pwait;			/* Queue of procs waiting for memory */
+	int	wanted;			/* Do the wakeup at free */
 };
 
 enum					/* Argument to forkpgrp call */


@@ 523,37 523,37 @@ struct Qinfo
 /*
  *  Queue.flag
  */
-#define QHUNGUP	0x1	/* flag bit meaning the stream has been hung up */
+#define QHUNGUP	0x1			/* flag bit meaning the stream has been hung up */
 #define QINUSE	0x2
-#define QHIWAT	0x4	/* queue has gone past the high water mark */	
+#define QHIWAT	0x4			/* queue has gone past the high water mark */	
 #define QDEBUG	0x8
 
 struct Queue {
 	Blist;
 	int	flag;
-	Qinfo	*info;		/* line discipline definition */
-	Queue	*other;		/* opposite direction, same line discipline */
-	Queue	*next;		/* next queue in the stream */
+	Qinfo	*info;			/* line discipline definition */
+	Queue	*other;			/* opposite direction, same line discipline */
+	Queue	*next;			/* next queue in the stream */
 	void	(*put)(Queue*, Block*);
-	QLock	rlock;		/* mutex for processes sleeping at r */
-	Rendez	r;		/* standard place to wait for flow control */
-	Rendez	*rp;		/* where flow control wakeups go to */
-	void	*ptr;		/* private info for the queue */
+	QLock	rlock;			/* mutex for processes sleeping at r */
+	Rendez	r;			/* standard place to wait for flow control */
+	Rendez	*rp;			/* where flow control wakeups go to */
+	void	*ptr;			/* private info for the queue */
 };
 
 struct Stream {
-	QLock;			/* structure lock */
-	short	inuse;		/* number of processes in stream */
-	short	opens;		/* number of processes with stream open */
-	ushort	hread;		/* number of reads after hangup */
-	ushort	type;		/* correlation with Chan */
-	ushort	dev;		/* ... */
-	ushort	id;		/* ... */
-	QLock	rdlock;		/* read lock */
-	Queue	*procq;		/* write queue at process end */
-	Queue	*devq;		/* read queue at device end */
-	Block	*err;		/* error message from down stream */
-	int	forcedelim;	/* force a delimiter before the next message */
+	QLock;				/* structure lock */
+	short	inuse;			/* number of processes in stream */
+	short	opens;			/* number of processes with stream open */
+	ushort	hread;			/* number of reads after hangup */
+	ushort	type;			/* correlation with Chan */
+	ushort	dev;			/* ... */
+	ushort	id;			/* ... */
+	QLock	rdlock;			/* read lock */
+	Queue	*procq;			/* write queue at process end */
+	Queue	*devq;			/* read queue at device end */
+	Block	*err;			/* error message from down stream */
+	int	forcedelim;		/* force a delimiter before the next message */
 };
 
 /*


@@ 578,13 578,13 @@ enum {
 	Sdataqid = Shighqid,
 	Sctlqid = Sdataqid-1,
 	Slowqid = Sctlqid,
-	Streamhi= (9*1024),	/* byte count high water mark */
-	Streambhi= 32,		/* block count high water mark */
+	Streamhi= (9*1024),		/* byte count high water mark */
+	Streambhi= 32,			/* block count high water mark */
 };
 
-#define MAXSYSARG	6	/* for mount(fd, mpt, flag, arg, srv, authfd) */
+#define MAXSYSARG	6		/* for mount(fd, mpt, flag, arg, srv, authfd) */
 #define	PRINTSIZE	256
-#define	NUMSIZE	12		/* size of formatted number */
+#define	NUMSIZE		12		/* size of formatted number */
 
 extern	FPsave	initfp;
 extern	Conf	conf;


@@ 600,6 600,3 @@ extern  Image	swapimage;
 #define	CHDIR		0x80000000L
 #define	CHAPPEND 	0x40000000L
 #define	CHEXCL		0x20000000L
-
-
-

@@ 196,7 196,10 @@ attachimage(int type, Chan *c, ulong base, ulong len)
 
 	lock(&imagealloc);
 
-	/* Search the image cache for remains of the text from a previous incarnation */
+	/*
+	 * Search the image cache for remains of the text from a previous 
+	 * or currently running incarnation 
+	 */
 	for(i = ihash(c->qid.path); i; i = i->hash) {
 		if(c->qid.path == i->qid.path) {
 			lock(i);


@@ 211,6 214,10 @@ attachimage(int type, Chan *c, ulong base, ulong len)
 		}
 	}
 	
+	/*
+	 * imagereclaim dumps pages from the free list which are cached by image
+	 * structures. This should free some image structures.
+	 */
 	while(!(i = imagealloc.free)) {
 		unlock(&imagealloc);
 		imagereclaim();


@@ 241,7 248,6 @@ found:
 	else
 		incref(i->s);
 
-	unlock(i);
 	return i;
 }
 

@@ 264,12 264,14 @@ sysexec(ulong *arg)
 		fdclose(i, CCEXEC);
 
 	/* Text.  Shared. Attaches to cache image if possible */
+	/* attachimage returns a locked cache image */
 	img = attachimage(SG_TEXT|SG_RONLY, tc, UTZERO, (t-UTZERO)>>PGSHIFT);
 	ts = img->s;
 	p->seg[TSEG] = ts;
 	ts->flushme = 1;
 	ts->fstart = 0;
 	ts->flen = sizeof(Exec)+text;
+	unlock(img);
 
 	/* Data. Shared. */
 	s = newseg(SG_DATA, t, (d-t)>>PGSHIFT);


@@ 408,6 410,7 @@ syserrstr(ulong *arg)
 
 	validaddr(arg[0], ERRLEN, 1);
 	memmove((char*)arg[0], u->error, ERRLEN);
+	strncpy(u->error, errstrtab[0], ERRLEN);
 	return 0;
 }
 

@@ 1,5 1,5 @@
 enum{
-	Enevermind,	/* never mind */
+	Enoerror,	/* no error */
 	Enofd,		/* no free file descriptors */
 	Ebadfd,		/* fd out of range or not open */
 	Ebadusefd,	/* inappropriate use of fd */

@@ 284,7 284,6 @@ noted(Ureg **urp, ulong arg0)
 	}
 	u->notified = 0;
 	memmove(*urp, u->ureg, sizeof(Ureg));
-	(*urp)->r7 = -1;	/* return error from the interrupted call */
 	switch(arg0){
 	case NCONT:
 		splhi();


@@ 412,7 411,7 @@ syscall(Ureg *aur)
 	u->p->insyscall = 0;
 	if(r7 == NOTED)	/* ugly hack */
 		noted(&aur, *(ulong*)(sp+1*BY2WD));	/* doesn't return */
-	if(u->nnote){
+	if(u->nnote && r7!=FORK){
 		ur->r7 = ret;
 		notify(ur);
 	}