--- ray/src/hd/holofile.c	1998/11/09 17:10:53	3.28
+++ ray/src/hd/holofile.c	1999/08/05 15:53:09	3.41
@@ -1,4 +1,4 @@
-/* Copyright (c) 1998 Silicon Graphics, Inc. */
+/* Copyright (c) 1999 Regents of the University of California */
 
 #ifndef lint
 static char SCCSid[] = "$SunId$ SGI";
@@ -13,33 +13,46 @@ static char SCCSid[] = "$SunId$ SGI";
 #include "holo.h"
 
 #ifndef CACHESIZE
-#define CACHESIZE	16	/* default cache size (Mbytes, 0==inf) */
+#ifdef BIGMEM
+#define CACHESIZE	17	/* default cache size (Mbytes, 0==inf) */
+#else
+#define CACHESIZE	5
 #endif
+#endif
 #ifndef FREEBEAMS
 #define FREEBEAMS	1500	/* maximum beams to free at a time */
 #endif
 #ifndef PCTFREE
 #define PCTFREE		15	/* maximum fraction to free (%) */
 #endif
-#ifndef MAXFRAG
-#define MAXFRAG		32767	/* maximum fragments/file to track (0==inf) */
+#ifndef MAXFRAGB
+#define MAXFRAGB	16	/* fragment blocks/file to track (0==inf) */
 #endif
+#ifndef FF_DEFAULT
+				/* when to free a beam fragment */
+#define FF_DEFAULT	(FF_WRITE|FF_KILL)
+#endif
+#ifndef MINDIRSEL
+				/* minimum directory seek length */
+#define MINDIRSEL	(4*BUFSIZ/sizeof(BEAMI))
+#endif
 
 #ifndef BSD
 #define write	writebuf	/* safe i/o routines */
 #define read	readbuf
 #endif
 
-#define FRAGBLK		256	/* number of fragments to allocate at a time */
+#define FRAGBLK		512	/* number of fragments to allocate at a time */
 
+int	hdfragflags = FF_DEFAULT;	/* tells when to free fragments */
 unsigned	hdcachesize = CACHESIZE*1024*1024;	/* target cache size */
-unsigned long	hdclock;	/* clock value */
+unsigned long	hdclock;		/* clock value */
 
 HOLO	*hdlist[HDMAX+1];	/* holodeck pointers (NULL term.) */
 
 static struct fraglist {
 	short	nlinks;		/* number of holodeck sections using us */
-	short	writerr;	/* write error encountered */
+	short	writable;	/* 0 read-only, <0 write error encountered */
 	int	nfrags;		/* number of known fragments */
 	BEAMI	*fi;		/* fragments, descending file position */
 	long	flen;		/* last known file length */
@@ -48,6 +61,40 @@ static struct fraglist {
 static int	nhdfragls;	/* size of hdfragl array */
 
 
+HOLO *
+hdalloc(hproto)		/* allocate and set holodeck section based on grid */
+HDGRID	*hproto;
+{
+	HOLO	hdhead;
+	register HOLO	*hp;
+	int	n;
+				/* copy grid to temporary header */
+	bcopy((char *)hproto, (char *)&hdhead, sizeof(HDGRID));
+				/* compute grid vectors and sizes */
+	hdcompgrid(&hdhead);
+				/* allocate header with directory */
+	n = sizeof(HOLO)+nbeams(&hdhead)*sizeof(BEAMI);
+	if ((hp = (HOLO *)malloc(n)) == NULL)
+		return(NULL);
+				/* copy header information */
+	copystruct(hp, &hdhead);
+				/* allocate and clear beam list */
+	hp->bl = (BEAM **)malloc((nbeams(hp)+1)*sizeof(BEAM *)+sizeof(BEAM));
+	if (hp->bl == NULL) {
+		free((char *)hp);
+		return(NULL);
+	}
+	bzero((char *)hp->bl, (nbeams(hp)+1)*sizeof(BEAM *)+sizeof(BEAM));
+	hp->bl[0] = (BEAM *)(hp->bl+nbeams(hp)+1);	/* set blglob(hp) */
+	hp->fd = -1;
+	hp->dirty = 0;
+	hp->priv = NULL;
+				/* clear beam directory */
+	bzero((char *)hp->bi, (nbeams(hp)+1)*sizeof(BEAMI));
+	return(hp);		/* all is well */
+}
+
+
 char *
 hdrealloc(ptr, siz, rout)	/* (re)allocate memory, retry then error */
 char	*ptr;
@@ -72,8 +119,9 @@ char	*rout;
 }
 
 
-hdattach(fd)		/* start tracking file fragments for some section */
+hdattach(fd, wr)	/* start tracking file fragments for some section */
 register int	fd;
+int	wr;
 {
 	if (fd >= nhdfragls) {
 		hdfragl = (struct fraglist *)hdrealloc((char *)hdfragl,
@@ -83,6 +131,7 @@ register int	fd;
 		nhdfragls = fd+1;
 	}
 	hdfragl[fd].nlinks++;
+	hdfragl[fd].writable = wr;		/* set writable flag */
 	hdfragl[fd].flen = lseek(fd, 0L, 2);	/* get file length */
 }
 
@@ -110,6 +159,7 @@ HDGRID	*hproto;		/* holodeck section grid */
 {
 	long	rtrunc;
 	long	fpos;
+	int	writable;
 	register HOLO	*hp;
 	register int	n;
 					/* prepare for system errors */
@@ -135,7 +185,14 @@ HDGRID	*hproto;		/* holodeck section grid */
 				error(WARNING, "dirty holodeck section");
 				break;
 			}
-	} else {			/* assume we're creating it */
+						/* check writability */
+		if (fd < nhdfragls && hdfragl[fd].nlinks)
+			writable = hdfragl[fd].writable;
+		else
+			writable = lseek(fd, fpos, 0) == fpos &&
+				write(fd, (char *)hp, sizeof(HDGRID)) ==
+							sizeof(HDGRID);
+	} else {			/* else assume we're creating it */
 		if ((hp = hdalloc(hproto)) == NULL)
 			goto memerr;
 						/* write header and skeleton */
@@ -144,12 +201,13 @@ HDGRID	*hproto;		/* holodeck section grid */
 					sizeof(HDGRID) ||
 				write(fd, (char *)(hp->bi+1), n) != n)
 			error(SYSTEM, "cannot write header to holodeck file");
+		writable = 1;
 	}
 	hp->fd = fd;	
 	hp->dirty = 0;
 	biglob(hp)->fo = fpos + sizeof(HDGRID);
 					/* start tracking fragments */
-	hdattach(fd);
+	hdattach(fd, writable);
 					/* check rays on disk */
 	fpos = hdfilen(fd);
 	biglob(hp)->nrd = rtrunc = 0;
@@ -178,7 +236,7 @@ memerr:
 }
 
 
-markdirty(hp, i)		/* mark holodeck directory position dirty */
+hdmarkdirty(hp, i)		/* mark holodeck directory position dirty */
 register HOLO	*hp;
 int	i;
 {
@@ -190,7 +248,7 @@ int	i;
 		if (lseek(hp->fd, biglob(hp)->fo+(i-1)*sizeof(BEAMI), 0) < 0
 				|| write(hp->fd, (char *)&smudge,
 					sizeof(BEAMI)) != sizeof(BEAMI))
-			error(SYSTEM, "seek/write error in markdirty");
+			error(SYSTEM, "seek/write error in hdmarkdirty");
 		hp->dirseg[0].s = i;
 		hp->dirseg[0].n = 1;
 		return;
@@ -204,25 +262,28 @@ int	i;
 		}
 		copystruct(hp->dirseg+j, hp->dirseg+(j-1));
 	}
-	mindist = nbeams(hp);			/* find closest neighbors */
-	for (j = hp->dirty; --j; )
-		if (hp->dirseg[j].s - (hp->dirseg[j-1].s + hp->dirseg[j-1].n)
-				< mindist) {
-			mindist = hp->dirseg[j].s -
+	do {				/* check neighbors */
+		mindist = nbeams(hp);		/* find closest */
+		for (j = hp->dirty; --j; )
+			if (hp->dirseg[j].s -
+					(hp->dirseg[j-1].s + hp->dirseg[j-1].n)
+					< mindist) {
+				minpos = j;
+				mindist = hp->dirseg[j].s -
 					(hp->dirseg[j-1].s + hp->dirseg[j-1].n);
-			minpos = j;
-		}
-	if (hp->dirty > MAXDIRSE || mindist <= BUFSIZ/sizeof(BEAMI)) {
+			}
+						/* good enough? */
+		if (hp->dirty <= MAXDIRSE && mindist > MINDIRSEL)
+			break;
 		j = minpos - 1;			/* coalesce neighbors */
 		if (hp->dirseg[j].s + hp->dirseg[j].n <
-				hp->dirseg[minpos].s + hp->dirseg[minpos].n) {
+				hp->dirseg[minpos].s + hp->dirseg[minpos].n)
 			hp->dirseg[j].n = hp->dirseg[minpos].s +
 					hp->dirseg[minpos].n - hp->dirseg[j].s;
-		}
-		hp->dirty--;			/* close the gap */
-		for (j = minpos; j < hp->dirty; j++)
+		hp->dirty--;
+		while (++j < hp->dirty)		/* close the gap */
 			copystruct(hp->dirseg+j, hp->dirseg+(j+1));
-	}
+	} while (mindist <= MINDIRSEL);
 }
 
 
@@ -342,10 +403,9 @@ int	nr;			/* number of new rays desired */
 	RAYVAL	*p;
 	int	n;
 
-	if (nr <= 0)
-		return(NULL);
-	if (i < 1 | i > nbeams(hp))
-		error(CONSISTENCY, "bad beam index given to hdnewrays");
+	if (nr <= 0) return(NULL);
+	CHECK(i < 1 | i > nbeams(hp),
+			CONSISTENCY, "bad beam index given to hdnewrays");
 	if (hp->bl[i] != NULL)
 		hp->bl[i]->tick = hdclock;	/* preempt swap */
 	if (hdcachesize > 0 && hdmemuse(0) >= hdcachesize)
@@ -354,7 +414,7 @@ int	nr;			/* number of new rays desired */
 		n = hp->bi[i].nrd + nr;
 		hp->bl[i] = (BEAM *)hdrealloc(NULL, hdbsiz(n), "hdnewrays");
 		blglob(hp)->nrm += n;
-		if (n = hp->bl[i]->nrm = hp->bi[i].nrd) {
+		if ((n = hp->bl[i]->nrm = hp->bi[i].nrd)) {
 			errno = 0;
 			if (lseek(hp->fd, hp->bi[i].fo, 0) < 0)
 				error(SYSTEM, "seek error on holodeck file");
@@ -368,6 +428,8 @@ int	nr;			/* number of new rays desired */
 				hdbsiz(hp->bl[i]->nrm + nr), "hdnewrays");
 		blglob(hp)->nrm += nr;
 	}
+	if (hdfragflags&FF_ALLOC && hp->bi[i].nrd)
+		hdfreefrag(hp, i);		/* relinquish old fragment */
 	p = hdbray(hp->bl[i]) + hp->bl[i]->nrm;
 	hp->bl[i]->nrm += nr;			/* update in-core structure */
 	bzero((char *)p, nr*sizeof(RAYVAL));
@@ -383,8 +445,8 @@ register int	i;
 {
 	register int	n;
 
-	if (i < 1 | i > nbeams(hp))
-		error(CONSISTENCY, "bad beam index given to hdgetbeam");
+	CHECK(i < 1 | i > nbeams(hp),
+			CONSISTENCY, "bad beam index given to hdgetbeam");
 	if (hp->bl[i] == NULL) {		/* load from disk */
 		if (!(n = hp->bi[i].nrd))
 			return(NULL);
@@ -398,6 +460,8 @@ register int	i;
 		n *= sizeof(RAYVAL);
 		if (read(hp->fd, (char *)hdbray(hp->bl[i]), n) != n)
 			error(SYSTEM, "error reading beam from holodeck file");
+		if (hdfragflags&FF_READ)
+			hdfreefrag(hp, i);	/* relinquish old frag. */
 	}
 	blglob(hp)->tick = hp->bl[i]->tick = hdclock++;	/* update LRU clock */
 	return(hp->bl[i]);
@@ -435,7 +499,7 @@ int	(*bf)();		/* callback function (optional) */
 					/* precheck consistency */
 	if (n <= 0) return;
 	for (i = n; i--; )
-		if (hb[i].h == NULL || hb[i].b < 1 | hb[i].b > nbeams(hb[i].h))
+		if (hb[i].h==NULL || hb[i].b<1 | hb[i].b>nbeams(hb[i].h))
 			error(CONSISTENCY, "bad beam in hdloadbeams");
 					/* sort list for optimal access */
 	qsort((char *)hb, n, sizeof(HDBEAMI), hdfilord);
@@ -468,20 +532,22 @@ int	(*bf)();		/* callback function (optional) */
 }
 
 
-hdfreefrag(fd, bi)			/* free a file fragment */
-int	fd;
-register BEAMI	*bi;
+int
+hdfreefrag(hp, i)			/* free a file fragment */
+HOLO	*hp;
+int	i;
 {
+	register BEAMI	*bi = &hp->bi[i];
 	register struct fraglist	*f;
 	register int	j, k;
 
-	if (bi->nrd == 0)
-		return;
-#ifdef DEBUG
-	if (fd < 0 | fd >= nhdfragls || !hdfragl[fd].nlinks)
-		error(CONSISTENCY, "bad file descriptor in hdfreefrag");
-#endif
-	f = &hdfragl[fd];
+	if (bi->nrd <= 0)
+		return(0);
+	DCHECK(hp->fd < 0 | hp->fd >= nhdfragls || !hdfragl[hp->fd].nlinks,
+			CONSISTENCY, "bad file descriptor in hdfreefrag");
+	f = &hdfragl[hp->fd];
+	if (!f->writable)
+		return(0);
 	if (f->nfrags % FRAGBLK == 0) {	/* delete empty remnants */
 		for (j = k = 0; k < f->nfrags; j++, k++) {
 			while (f->fi[k].nrd == 0)
@@ -494,11 +560,14 @@ register BEAMI	*bi;
 		f->nfrags = j;
 	}
 	j = f->nfrags++;		/* allocate a slot in free list */
-#if MAXFRAG
-	if (j >= MAXFRAG-1)
-		f->nfrags--;
+#if MAXFRAGB
+	if (j >= MAXFRAGB*FRAGBLK) {
+		f->nfrags = j--;	/* stop list growth */
+		if (bi->nrd <= f->fi[j].nrd)
+			return(0);	/* new one no better than discard */
+	}
 #endif
-	if (j % FRAGBLK == 0) {		/* more free list space */
+	if (j % FRAGBLK == 0) {		/* more (or less) free list space */
 		register BEAMI	*newp;
 		if (f->fi == NULL)
 			newp = (BEAMI *)malloc((j+FRAGBLK)*sizeof(BEAMI));
@@ -507,7 +576,7 @@ register BEAMI	*bi;
 					(j+FRAGBLK)*sizeof(BEAMI));
 		if (newp == NULL) {
 			f->nfrags--;	/* graceful failure */
-			return;
+			return(0);
 		}
 		f->fi = newp;
 	}
@@ -534,38 +603,62 @@ register BEAMI	*bi;
 			}
 			break;
 		}
+	biglob(hp)->nrd -= bi->nrd;		/* tell fragment it's free */
+	bi->nrd = 0;
+	bi->fo = 0L;
+	hdmarkdirty(hp, i);			/* assume we'll reallocate */
+	return(1);
 }
 
 
+int
+hdfragOK(fd, listlen, listsiz)	/* get fragment list status for file */
+int	fd;
+int	*listlen;
+register int4	*listsiz;
+{
+	register struct fraglist	*f;
+	register int	i;
+
+	if (fd < 0 | fd >= nhdfragls || !(f = &hdfragl[fd])->nlinks)
+		return(0);		/* listless */
+	if (listlen != NULL)
+		*listlen = f->nfrags;
+	if (listsiz != NULL)
+		for (i = f->nfrags, *listsiz = 0; i--; )
+			*listsiz += f->fi[i].nrd;
+#if MAXFRAGB
+	return(f->nfrags < MAXFRAGB*FRAGBLK);
+#else
+	return(1);			/* list never fills up */
+#endif
+}
+
+
 long
 hdallocfrag(fd, nrays)		/* allocate a file fragment */
 int	fd;
 unsigned int4	nrays;
 {
 	register struct fraglist	*f;
-	register int	j, k;
+	register int	j;
 	long	nfo;
 
 	if (nrays == 0)
 		return(-1L);
-#ifdef DEBUG
-	if (fd < 0 | fd >= nhdfragls || !hdfragl[fd].nlinks)
-		error(CONSISTENCY, "bad file descriptor in hdallocfrag");
-#endif
+	DCHECK(fd < 0 | fd >= nhdfragls || !hdfragl[fd].nlinks,
+			CONSISTENCY, "bad file descriptor in hdallocfrag");
 	f = &hdfragl[fd];
-	k = -1;				/* find closest-sized fragment */
-	for (j = f->nfrags; j-- > 0; )
-		if (f->fi[j].nrd >= nrays &&
-				(k < 0 || f->fi[j].nrd < f->fi[k].nrd))
-			if (f->fi[k=j].nrd == nrays)
-				break;
-	if (k < 0) {			/* no fragment -- extend file */
+	for (j = f->nfrags; j-- > 0; )	/* first fit algorithm */
+		if (f->fi[j].nrd >= nrays)
+			break;
+	if (j < 0) {			/* no fragment -- extend file */
 		nfo = f->flen;
 		f->flen += nrays*sizeof(RAYVAL);
 	} else {			/* else use fragment */
-		nfo = f->fi[k].fo;
-		f->fi[k].fo += nrays*sizeof(RAYVAL);
-		f->fi[k].nrd -= nrays;
+		nfo = f->fi[j].fo;
+		f->fi[j].fo += nrays*sizeof(RAYVAL);
+		f->fi[j].nrd -= nrays;
 	}
 	return(nfo);
 }
@@ -576,21 +669,20 @@ hdsyncbeam(hp, i)		/* sync beam in memory with beam on
 register HOLO	*hp;
 register int	i;
 {
+	int	fragfreed;
 	unsigned int4	nrays;
 	unsigned int	n;
 	long	nfo;
 					/* check file status */
-	if (hdfragl[hp->fd].writerr)
-		return(-1);
-#ifdef DEBUG
-	if (i < 1 | i > nbeams(hp))
-		error(CONSISTENCY, "bad beam index in hdsyncbeam");
-#endif
+	if (hdfragl[hp->fd].writable <= 0)
+		return(hdfragl[hp->fd].writable);
+	DCHECK(i < 1 | i > nbeams(hp),
+			CONSISTENCY, "bad beam index in hdsyncbeam");
 					/* is current fragment OK? */
 	if (hp->bl[i] == NULL || (nrays = hp->bl[i]->nrm) == hp->bi[i].nrd)
 		return(0);
-	if (hp->bi[i].nrd)		/* relinquish old fragment */
-		hdfreefrag(hp->fd, &hp->bi[i]);
+					/* relinquish old fragment? */
+	fragfreed = hdfragflags&FF_WRITE && hp->bi[i].nrd && hdfreefrag(hp,i);
 	if (nrays) {			/* get and write new fragment */
 		nfo = hdallocfrag(hp->fd, nrays);
 		errno = 0;
@@ -598,7 +690,7 @@ register int	i;
 			error(SYSTEM, "cannot seek on holodeck file");
 		n = hp->bl[i]->nrm * sizeof(RAYVAL);
 		if (write(hp->fd, (char *)hdbray(hp->bl[i]), n) != n) {
-			hdfragl[hp->fd].writerr++;
+			hdfragl[hp->fd].writable = -1;
 			hdsync(NULL, 0);	/* sync directories */
 			error(SYSTEM, "write error in hdsyncbeam");
 		}
@@ -607,7 +699,8 @@ register int	i;
 		hp->bi[i].fo = 0L;
 	biglob(hp)->nrd += nrays - hp->bi[i].nrd;
 	hp->bi[i].nrd = nrays;
-	markdirty(hp, i);		/* section directory now out of date */
+	if (!fragfreed)
+		hdmarkdirty(hp, i);		/* need to flag dir. ent. */
 	return(1);
 }
 
@@ -625,19 +718,21 @@ register int	i;
 			nchanged += hdfreebeam(hdlist[i], 0);
 		return(nchanged);
 	}
-	if (hdfragl[hp->fd].writerr)	/* check for file error */
+	if (hdfragl[hp->fd].writable < 0)	/* check for file error */
 		return(0);
 	if (i == 0) {			/* clear entire holodeck */
+		if (blglob(hp)->nrm == 0)
+			return(0);		/* already clear */
 		nchanged = 0;
 		for (i = nbeams(hp); i > 0; i--)
 			if (hp->bl[i] != NULL)
 				nchanged += hdfreebeam(hp, i);
+		DCHECK(blglob(hp)->nrm != 0,
+				CONSISTENCY, "bad beam count in hdfreebeam");
 		return(nchanged);
 	}
-#ifdef DEBUG
-	if (i < 1 | i > nbeams(hp))
-		error(CONSISTENCY, "bad beam index to hdfreebeam");
-#endif
+	DCHECK(i < 1 | i > nbeams(hp),
+			CONSISTENCY, "bad beam index to hdfreebeam");
 	if (hp->bl[i] == NULL)
 		return(0);
 					/* check for additions */
@@ -656,7 +751,6 @@ hdkillbeam(hp, i)		/* delete beam from holodeck */
 register HOLO	*hp;
 register int	i;
 {
-	static BEAM	emptybeam;
 	int	nchanged;
 
 	if (hp == NULL) {		/* clobber all holodecks */
@@ -666,30 +760,33 @@ register int	i;
 		return(nchanged);
 	}
 	if (i == 0) {			/* clobber entire holodeck */
+		if (biglob(hp)->nrd == 0 & blglob(hp)->nrm == 0)
+			return(0);		/* already empty */
 		nchanged = 0;
+		nchanged = 0;
 		for (i = nbeams(hp); i > 0; i--)
 			if (hp->bi[i].nrd > 0 || hp->bl[i] != NULL)
 				nchanged += hdkillbeam(hp, i);
-#ifdef DEBUG
-		if (biglob(hp)->nrd != 0 | blglob(hp)->nrm != 0)
-			error(CONSISTENCY, "bad beam count in hdkillbeam");
-#endif
+		DCHECK(biglob(hp)->nrd != 0 | blglob(hp)->nrm != 0,
+				CONSISTENCY, "bad beam count in hdkillbeam");
 		return(nchanged);
 	}
-#ifdef DEBUG
-	if (i < 1 | i > nbeams(hp))
-		error(CONSISTENCY, "bad beam index to hdkillbeam");
-#endif
+	DCHECK(i < 1 | i > nbeams(hp), CONSISTENCY,
+			"bad beam index to hdkillbeam");
+	DCHECK(!hdfragl[hp->fd].writable, CONSISTENCY,
+			"hdkillbeam called on read-only holodeck");
 	if (hp->bl[i] != NULL) {	/* free memory */
 		blglob(hp)->nrm -= nchanged = hp->bl[i]->nrm;
 		free((char *)hp->bl[i]);
+		hp->bl[i] = NULL;
 	} else
 		nchanged = hp->bi[i].nrd;
-	if (hp->bi[i].nrd) {		/* free file fragment */
-		hp->bl[i] = &emptybeam;
-		hdsyncbeam(hp, i);
+	if (hp->bi[i].nrd && !(hdfragflags&FF_KILL && hdfreefrag(hp,i))) {
+		biglob(hp)->nrd -= hp->bi[i].nrd;	/* free failed */
+		hp->bi[i].nrd = 0;
+		hp->bi[i].fo = 0L;
+		hdmarkdirty(hp, i);
 	}
-	hp->bl[i] = NULL;
 	return(nchanged);
 }
 
@@ -783,8 +880,7 @@ register HOLO	*hp;		/* NULL means clean up all */
 		return;
 	}
 					/* flush all data and free memory */
-	hdfreebeam(hp, 0);
-	hdsync(hp, 0);
+	hdflush(hp);
 					/* release fragment resources */
 	hdrelease(hp->fd);
 					/* remove hp from active list */