--- ray/src/hd/holofile.c	1999/03/09 08:40:11	3.39
+++ ray/src/hd/holofile.c	2003/05/13 17:58:33	3.44
@@ -1,9 +1,6 @@
-/* Copyright (c) 1999 Silicon Graphics, Inc. */
-
 #ifndef lint
-static char SCCSid[] = "$SunId$ SGI";
+static const char	RCSid[] = "$Id: holofile.c,v 3.44 2003/05/13 17:58:33 greg Exp $";
 #endif
-
 /*
  * Routines for managing holodeck files
  *
@@ -52,7 +49,7 @@ 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 */
@@ -61,6 +58,40 @@ 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((void *)hproto, (void *)&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((void *)hp);
+		return(NULL);
+	}
+	bzero((void *)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((void *)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;
@@ -70,7 +101,7 @@ char	*rout;
 	register char	*newp;
 					/* call malloc/realloc */
 	if (ptr == NULL) newp = (char *)malloc(siz);
-	else newp = (char *)realloc(ptr, siz);
+	else newp = (char *)realloc((void *)ptr, siz);
 					/* check success */
 	if (newp == NULL && rout != NULL) {
 		hdfreecache(25, NULL);	/* free some memory */
@@ -85,18 +116,20 @@ 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,
 				(fd+1)*sizeof(struct fraglist), "hdattach");
-		bzero((char *)(hdfragl+nhdfragls),
+		bzero((void *)(hdfragl+nhdfragls),
 				(fd+1-nhdfragls)*sizeof(struct fraglist));
 		nhdfragls = fd+1;
 	}
 	hdfragl[fd].nlinks++;
-	hdfragl[fd].flen = lseek(fd, 0L, 2);	/* get file length */
+	hdfragl[fd].writable = wr;		/* set writable flag */
+	hdfragl[fd].flen = lseek(fd, (off_t)0L, 2);	/* get file length */
 }
 
 
@@ -109,7 +142,7 @@ register int	fd;
 	if (fd < 0 | fd >= nhdfragls || !hdfragl[fd].nlinks)
 		return;
 	if (!--hdfragl[fd].nlinks && hdfragl[fd].nfrags) {
-		free((char *)hdfragl[fd].fi);
+		free((void *)hdfragl[fd].fi);
 		hdfragl[fd].fi = NULL;
 		hdfragl[fd].nfrags = 0;
 	}
@@ -123,11 +156,12 @@ HDGRID	*hproto;		/* holodeck section grid */
 {
 	long	rtrunc;
 	long	fpos;
+	int	writable;
 	register HOLO	*hp;
 	register int	n;
 					/* prepare for system errors */
 	errno = 0;
-	if ((fpos = lseek(fd, 0L, 1)) < 0)
+	if ((fpos = lseek(fd, (off_t)0L, 1)) < 0)
 		error(SYSTEM, "cannot determine holodeck file position");
 	if (hproto == NULL) {		/* assume we're loading it */
 		HDGRID	hpr;
@@ -148,7 +182,14 @@ 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, (off_t)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 */
@@ -157,12 +198,13 @@ 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;
@@ -200,7 +242,7 @@ int	i;
 	register int	j;
 
 	if (!hp->dirty++) {			/* write smudge first time */
-		if (lseek(hp->fd, biglob(hp)->fo+(i-1)*sizeof(BEAMI), 0) < 0
+		if (lseek(hp->fd, (off_t)(biglob(hp)->fo+(i-1)*sizeof(BEAMI)), 0) < 0
 				|| write(hp->fd, (char *)&smudge,
 					sizeof(BEAMI)) != sizeof(BEAMI))
 			error(SYSTEM, "seek/write error in hdmarkdirty");
@@ -263,8 +305,8 @@ int	all;
 		return(0);
 	errno = 0;			/* write dirty segments */
 	for (j = 0; j < hp->dirty; j++) {
-		if (lseek(hp->fd, biglob(hp)->fo +
-				(hp->dirseg[j].s-1)*sizeof(BEAMI), 0) < 0)
+		if (lseek(hp->fd, (off_t)(biglob(hp)->fo +
+				(hp->dirseg[j].s-1)*sizeof(BEAMI)), 0) < 0)
 			error(SYSTEM, "cannot seek on holodeck file");
 		n = hp->dirseg[j].n * sizeof(BEAMI);
 		if (write(hp->fd, (char *)(hp->bi+hp->dirseg[j].s), n) != n)
@@ -313,10 +355,10 @@ int	fd;
 	if (fd < 0)
 		return(-1);
 	if (fd >= nhdfragls || !hdfragl[fd].nlinks) {
-		if ((fpos = lseek(fd, 0L, 1)) < 0)
+		if ((fpos = lseek(fd, (off_t)0L, 1)) < 0)
 			return(-1);
-		flen = lseek(fd, 0L, 2);
-		lseek(fd, fpos, 0);
+		flen = lseek(fd, (off_t)0L, 2);
+		lseek(fd, (off_t)fpos, 0);
 		return(flen);
 	}
 	return(hdfragl[fd].flen);
@@ -371,7 +413,7 @@ int	nr;			/* number of new rays desired */
 		blglob(hp)->nrm += n;
 		if ((n = hp->bl[i]->nrm = hp->bi[i].nrd)) {
 			errno = 0;
-			if (lseek(hp->fd, hp->bi[i].fo, 0) < 0)
+			if (lseek(hp->fd, (off_t)hp->bi[i].fo, 0) < 0)
 				error(SYSTEM, "seek error on holodeck file");
 			n *= sizeof(RAYVAL);
 			if (read(hp->fd, (char *)hdbray(hp->bl[i]), n) != n)
@@ -387,7 +429,7 @@ int	nr;			/* number of new rays desired */
 		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));
+	bzero((void *)p, nr*sizeof(RAYVAL));
 	blglob(hp)->tick = hp->bl[i]->tick = hdclock++;	/* update LRU clock */
 	return(p);				/* point to new rays */
 }
@@ -410,7 +452,7 @@ register int	i;
 		hp->bl[i] = (BEAM *)hdrealloc(NULL, hdbsiz(n), "hdgetbeam");
 		blglob(hp)->nrm += hp->bl[i]->nrm = n;
 		errno = 0;
-		if (lseek(hp->fd, hp->bi[i].fo, 0) < 0)
+		if (lseek(hp->fd, (off_t)hp->bi[i].fo, 0) < 0)
 			error(SYSTEM, "seek error on holodeck file");
 		n *= sizeof(RAYVAL);
 		if (read(hp->fd, (char *)hdbray(hp->bl[i]), n) != n)
@@ -457,7 +499,7 @@ int	(*bf)();		/* callback function (optional) */
 		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);
+	qsort((void *)hb, n, sizeof(HDBEAMI), hdfilord);
 	bytesloaded = 0;		/* run through loaded beams */
 	for ( ; n && (bp = hb->h->bl[hb->b]) != NULL; n--, hb++) {
 		bp->tick = hdclock;	/* preempt swap */
@@ -501,6 +543,8 @@ int	i;
 	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)
@@ -525,7 +569,7 @@ int	i;
 		if (f->fi == NULL)
 			newp = (BEAMI *)malloc((j+FRAGBLK)*sizeof(BEAMI));
 		else
-			newp = (BEAMI *)realloc((char *)f->fi,
+			newp = (BEAMI *)realloc((void *)f->fi,
 					(j+FRAGBLK)*sizeof(BEAMI));
 		if (newp == NULL) {
 			f->nfrags--;	/* graceful failure */
@@ -627,8 +671,8 @@ register int	i;
 	unsigned int	n;
 	long	nfo;
 					/* check file status */
-	if (hdfragl[hp->fd].writerr)
-		return(-1);
+	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? */
@@ -639,11 +683,11 @@ register int	i;
 	if (nrays) {			/* get and write new fragment */
 		nfo = hdallocfrag(hp->fd, nrays);
 		errno = 0;
-		if (lseek(hp->fd, nfo, 0) < 0)
+		if (lseek(hp->fd, (off_t)nfo, 0) < 0)
 			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");
 		}
@@ -671,7 +715,7 @@ 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)
@@ -693,7 +737,7 @@ register int	i;
 	if (nchanged)
 		hdsyncbeam(hp, i);		/* write new fragment */
 	blglob(hp)->nrm -= hp->bl[i]->nrm;
-	free((char *)hp->bl[i]);		/* free memory */
+	free((void *)hp->bl[i]);		/* free memory */
 	hp->bl[i] = NULL;
 	return(nchanged);
 }
@@ -724,11 +768,13 @@ register int	i;
 				CONSISTENCY, "bad beam count in hdkillbeam");
 		return(nchanged);
 	}
-	DCHECK(i < 1 | i > nbeams(hp),
-			CONSISTENCY, "bad beam index to hdkillbeam");
+	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]);
+		free((void *)hp->bl[i]);
 		hp->bl[i] = NULL;
 	} else
 		nchanged = hp->bi[i].nrd;
@@ -826,7 +872,7 @@ register HOLO	*hp;		/* NULL means clean up all */
 	if (hp == NULL) {		/* NULL means clean up everything */
 		while (hdlist[0] != NULL)
 			hddone(hdlist[0]);
-		free((char *)hdfragl);
+		free((void *)hdfragl);
 		hdfragl = NULL; nhdfragls = 0;
 		return;
 	}
@@ -841,6 +887,6 @@ register HOLO	*hp;		/* NULL means clean up all */
 				i++;
 			break;
 		}
-	free((char *)hp->bl);		/* free beam list */
-	free((char *)hp);		/* free holodeck struct */
+	free((void *)hp->bl);		/* free beam list */
+	free((void *)hp);		/* free holodeck struct */
 }