--- ray/src/util/rpiece.c	1992/08/08 18:47:39	2.7
+++ ray/src/util/rpiece.c	1992/12/02 17:07:00	2.14
@@ -15,12 +15,24 @@ static char SCCSid[] = "$SunId$ LBL";
 #include "view.h"
 #include "resolu.h"
 
+#ifndef NFS
+#define  NFS			1
+#endif
+				/* set the following to 0 to forgo forking */
+#ifndef MAXFORK
+#if NFS
+#define  MAXFORK		3	/* allotment of duped processes */
+#else
+#define  MAXFORK		0
+#endif
+#endif
+
 				/* rpict command */
 char  *rpargv[128] = {"rpict", "-S", "1", "-x", "512", "-y", "512", "-pa", "1"};
 int  rpargc = 9;
 int  rpd[3];
 FILE  *torp, *fromrp;
-COLR  *scanline;
+COLR  *pbuf;
 				/* our view parameters */
 VIEW  ourview = STDVIEW;
 double  pixaspect = 1.0;
@@ -30,6 +42,7 @@ char  *outfile = NULL;
 int  outfd;
 long  scanorig;
 int  syncfd = -1;		/* lock file descriptor */
+int  nforked = 0;
 
 char  *progname;
 int  verbose = 0;
@@ -96,7 +109,8 @@ char  *argv[];
 			case 'F':		/* syncronization file */
 				if (argv[i][2])
 					break;
-				if ((syncfd = open(argv[++i], O_RDWR)) < 0) {
+				if ((syncfd = open(argv[++i],
+						O_RDWR|O_CREAT, 0666)) < 0) {
 					fprintf(stderr, "%s: cannot open\n",
 							argv[i]);
 					exit(1);
@@ -117,7 +131,7 @@ char  *argv[];
 	}
 	init(argc, argv);
 	rpiece();
-	rval = cleanup();
+	rval = cleanup(0);
 	exit(rval);
 }
 
@@ -158,20 +172,24 @@ char  **av;
 	} else if ((outfd = open(outfile, O_RDWR)) >= 0) {
 		if ((fp = fdopen(dup(outfd), "r+")) == NULL)
 			goto filerr;
-		getheader(fp, NULL);		/* skip header */
+		getheader(fp, NULL, NULL);	/* skip header */
 		if (fscnresolu(&hr, &vr, fp) < 0 ||	/* check resolution */
 				hr != hres*hmult || vr != vres*vmult) {
-			fprintf(stderr, "%s: picture resolution mismatch\n",
-					outfile);
+			fprintf(stderr, "%s: resolution mismatch on file \"%s\"\n",
+					progname, outfile);
 			exit(1);
 		}
 	} else {
-		fprintf(stderr, "%s: cannot open\n", outfile);
+		fprintf(stderr, "%s: cannot open file \"%s\"\n",
+				progname, outfile);
 		exit(1);
 	}
 	scanorig = ftell(fp);		/* record position of first scanline */
 	if (fclose(fp) == -1)		/* done with stream i/o */
 		goto filerr;
+#if NFS
+	sync();				/* flush NFS buffers */
+#endif
 					/* start rpict process */
 	if (open_process(rpd, rpargv) <= 0) {
 		fprintf(stderr, "%s: cannot start %s\n", progname, rpargv[0]);
@@ -183,14 +201,14 @@ char  **av;
 				progname, rpargv[0]);
 		exit(1);
 	}
-	if ((scanline = (COLR *)malloc(hres*sizeof(COLR))) == NULL) {
+	if ((pbuf = (COLR *)malloc(hres*vres*sizeof(COLR))) == NULL) {
 		fprintf(stderr, "%s: out of memory\n", progname);
 		exit(1);
 	}
 	signal(SIGALRM, onalrm);
 	return;
 filerr:
-	fprintf(stderr, "%s: file i/o error\n", outfile);
+	fprintf(stderr, "%s: i/o error on file \"%s\"\n", progname, outfile);
 	exit(1);
 }
 
@@ -214,12 +232,12 @@ int  *xp, *yp;
 		lseek(syncfd, 0L, 0);
 		buf[read(syncfd, buf, sizeof(buf)-1)] = '\0';
 		if (sscanf(buf, "%*d %*d %d %d", xp, yp) < 2) {
-			*xp = hmult;
-			*yp = vmult-1;
-		}
-		if (--(*xp) < 0) {		/* decrement position */
 			*xp = hmult-1;
-			if (--(*yp) < 0) {	/* all done! */
+			*yp = vmult;
+		}
+		if (--(*yp) < 0) {		/* decrement position */
+			*yp = vmult-1;
+			if (--(*xp) < 0) {	/* all done! */
 				close(syncfd);
 				return(0);
 			}
@@ -236,22 +254,23 @@ int  *xp, *yp;
 	if (sscanf(buf, "%d %d", xp, yp) == 2)
 		return(1);
 	fprintf(stderr, "%s: input format error\n", progname);
-	exit(1);
+	exit(cleanup(1));
 }
 
 
 int
-cleanup()			/* close rpict process and clean up */
+cleanup(rstat)			/* close rpict process and clean up */
+int  rstat;
 {
-	register int  rpstat;
+	int  status;
 
-	free((char *)scanline);
+	free((char *)pbuf);
 	fclose(torp);
 	fclose(fromrp);
-	rpstat = close_process(rpd);
-	if (rpstat == -1)
-		rpstat = 0;
-	return(rpstat);
+	while (wait(&status) != -1)
+		if (rstat == 0)
+			rstat = status>>8 & 0xff;
+	return(rstat);
 }
 
 
@@ -259,38 +278,39 @@ rpiece()			/* render picture piece by piece */
 {
 	VIEW  pview;
 	int  xorg, yorg;
-	
+					/* compute view parameters */
+	copystruct(&pview, &ourview);
+	switch (ourview.type) {
+	case VT_PER:
+		pview.horiz = 2.*180./PI*atan(
+				tan(PI/180./2.*ourview.horiz)/hmult );
+		pview.vert = 2.*180./PI*atan(
+				tan(PI/180./2.*ourview.vert)/vmult );
+		break;
+	case VT_PAR:
+	case VT_ANG:
+		pview.horiz = ourview.horiz / hmult;
+		pview.vert = ourview.vert / vmult;
+		break;
+	case VT_HEM:
+		pview.horiz = 2.*180./PI*asin(
+				sin(PI/180./2.*ourview.horiz)/hmult );
+		pview.vert = 2.*180./PI*asin(
+				sin(PI/180./2.*ourview.vert)/vmult );
+		break;
+	default:
+		fprintf(stderr, "%s: unknown view type '-vt%c'\n",
+				progname, ourview.type);
+		exit(cleanup(1));
+	}
+					/* render each piece */
 	while (nextpiece(&xorg, &yorg)) {
-		copystruct(&pview, &ourview);	/* compute view for piece */
-		switch (ourview.type) {
-		case VT_PER:
-			pview.horiz = 2.*180./PI*atan(
-					tan(PI/180./2.*ourview.horiz)/hmult );
-			pview.vert = 2.*180./PI*atan(
-					tan(PI/180./2.*ourview.vert)/vmult );
-			break;
-		case VT_PAR:
-		case VT_ANG:
-			pview.horiz = ourview.horiz / hmult;
-			pview.vert = ourview.vert / vmult;
-			break;
-		case VT_HEM:
-			pview.horiz = 2.*180./PI*asin(
-					sin(PI/180./2.*ourview.horiz)/hmult );
-			pview.vert = 2.*180./PI*asin(
-					sin(PI/180./2.*ourview.vert)/vmult );
-			break;
-		default:
-			fprintf(stderr, "%s: unknown view type '-vt%c'\n",
-					progname, ourview.type);
-			exit(1);
-		}
-		pview.hoff += xorg - 0.5*(hmult-1);
-		pview.voff += yorg - 0.5*(vmult-1);
+		pview.hoff = ourview.hoff + xorg - 0.5*(hmult-1);
+		pview.voff = ourview.voff + yorg - 0.5*(vmult-1);
 		fputs(VIEWSTR, torp);
 		fprintview(&pview, torp);
 		putc('\n', torp);
-		fflush(torp);			/* assign piece to rpict */
+		fflush(torp);			/* assigns piece to rpict */
 		putpiece(xorg, yorg);		/* place piece in output */
 		if (verbose) {			/* notify caller */
 			printf("%d %d done\n", xorg, yorg);
@@ -300,48 +320,85 @@ rpiece()			/* render picture piece by piece */
 }
 
 
+int
 putpiece(xpos, ypos)		/* get next piece from rpict */
 int  xpos, ypos;
 {
 	struct flock  fls;
+	int  pid, status;
 	int  hr, vr;
-	int  y;
-
+	register int  y;
+				/* check bounds */
 	if (xpos < 0 | ypos < 0 | xpos >= hmult | ypos >= vmult) {
 		fprintf(stderr, "%s: requested piece (%d,%d) out of range\n",
 				progname, xpos, ypos);
-		exit(1);
+		exit(cleanup(1));
 	}
-	getheader(fromrp, NULL);	/* discard header info. */
-	if (fscnresolu(&hr, &vr, fromrp) < 0 ||	/* check resolution */
-			hr != hres || vr != vres) {
+				/* check header from rpict */
+	getheader(fromrp, NULL, NULL);
+	if (fscnresolu(&hr, &vr, fromrp) < 0 || hr != hres | vr != vres) {
 		fprintf(stderr, "%s: resolution mismatch from %s\n",
 				progname, rpargv[0]);
-		exit(1);
+		exit(cleanup(1));
 	}
-	fls.l_whence = 1;
-	fls.l_start = 0L;
-	fls.l_len = hr*sizeof(COLR);
-	for (y = 0; y < vr; y++) {	/* transfer scanlines */
-		if (freadcolrs(scanline, hr, fromrp) < 0) {
+				/* load new piece into buffer */
+	for (y = 0; y < vr; y++)
+		if (freadcolrs(pbuf+y*hr, hr, fromrp) < 0) {
 			fprintf(stderr, "%s: read error from %s\n",
 					progname, rpargv[0]);
-			exit(1);
+			exit(cleanup(1));
 		}
-		if ((y == 0 || hmult != 1) && lseek(outfd,
-scanorig+((long)((vmult-1-ypos)*vres+y)*hmult*hres+xpos*hres)*sizeof(COLR),
-				0) == -1) {
-			fprintf(stderr, "%s: seek error\n", outfile);
-			exit(1);
+#if MAXFORK
+				/* fork so we don't slow rpict down */
+	if ((pid = fork()) > 0) {
+		if (++nforked >= MAXFORK) {
+			wait(&status);		/* reap a child */
+			if (status)
+				exit(cleanup(status>>8 & 0xff));
+			nforked--;
 		}
-		fls.l_type = F_WRLCK;
-		fcntl(outfd, F_SETLKW, &fls);
-		if (writebuf(outfd, (char *)scanline, hr*sizeof(COLR)) !=
-				hr*sizeof(COLR)) {
-			fprintf(stderr, "%s: write error\n", outfile);
-			exit(1);
+		return(pid);
+	}
+#else
+	pid = -1;		/* no forking */
+#endif
+#if NFS
+				/* lock file section so NFS doesn't mess up */
+	fls.l_whence = 0;
+	fls.l_len = (long)vres*hmult*hres*sizeof(COLR);
+	fls.l_start = scanorig + (vmult-1-ypos)*fls.l_len;
+	fls.l_type = F_WRLCK;
+	fcntl(outfd, F_SETLKW, &fls);
+#endif
+				/* write new piece to file */
+	if (lseek(outfd, fls.l_start+(long)xpos*hres*sizeof(COLR), 0) == -1)
+		goto seekerr;
+	if (hmult == 1) {
+		if (writebuf(outfd, (char *)pbuf,
+				vr*hr*sizeof(COLR)) != vr*hr*sizeof(COLR))
+			goto writerr;
+	} else
+		for (y = 0; y < vr; y++) {
+			if (writebuf(outfd, (char *)(pbuf+y*hr),
+					hr*sizeof(COLR)) != hr*sizeof(COLR))
+				goto writerr;
+			if (y < vr-1 && lseek(outfd,
+					(long)(hmult-1)*hr*sizeof(COLR),
+					1) == -1)
+				goto seekerr;
 		}
-		fls.l_type = F_UNLCK;
+	if (pid == -1) {	/* fork failed */
+#if NFS
+		fls.l_type = F_UNLCK;		/* release lock */
 		fcntl(outfd, F_SETLKW, &fls);
+#endif
+		return(0);
 	}
+	_exit(0);		/* else exit child process (releasing lock) */
+seekerr:
+	fprintf(stderr, "%s: seek error on file \"%s\"\n", progname, outfile);
+	_exit(1);
+writerr:
+	fprintf(stderr, "%s: write error on file \"%s\"\n", progname, outfile);
+	_exit(1);
 }