--- ray/src/rt/rc3.c	2012/06/09 16:47:27	2.2
+++ ray/src/rt/rc3.c	2012/11/15 19:41:03	2.18
@@ -1,20 +1,21 @@
 #ifndef lint
-static const char RCSid[] = "$Id: rc3.c,v 2.2 2012/06/09 16:47:27 greg Exp $";
+static const char RCSid[] = "$Id: rc3.c,v 2.18 2012/11/15 19:41:03 greg Exp $";
 #endif
 /*
  * Accumulate ray contributions for a set of materials
  * Controlling process for multiple children
  */
 
+#include <signal.h>
 #include "rcontrib.h"
-#include "platform.h"
-#include "rtprocess.h"
 #include "selcall.h"
 
+#define	MAXIQ		(int)(PIPE_BUF/(sizeof(FVECT)*2))
+
 /* Modifier contribution queue (results waiting to be output) */
 typedef struct s_binq {
-	int		ndx;		/* index for this entry */
-	int		n2add;		/* number left to add */
+	RNUMBER		ndx;		/* index for this entry */
+	RNUMBER		nadded;		/* accumulated so far */
 	struct s_binq	*next;		/* next in queue */
 	MODCONT		*mca[1];	/* contrib. array (extends struct) */
 } BINQ;
@@ -22,25 +23,30 @@ typedef struct s_binq {
 static BINQ	*out_bq = NULL;		/* output bin queue */
 static BINQ	*free_bq = NULL;	/* free queue entries */
 
-static SUBPROC	kida[MAXPROCESS];	/* child processes */
-static FILE	*inq_fp[MAXPROCESS];	/* input streams */
+static struct {
+	RNUMBER	r1;			/* assigned ray starting index */
+	SUBPROC	pr;			/* PID, i/o descriptors */
+	FILE	*infp;			/* file pointer to read from process */
+	int	nr;			/* number of rays to sum (0 if free) */
+} kida[MAXPROCESS];		/* our child processes */
 
 
-/* Get new (empty) bin queue entry */
+/* Get new bin queue entry */
 static BINQ *
 new_binq()
 {
-	BINQ	*bp = free_bq;
+	BINQ	*bp;
 	int	i;
 
-	if (bp != NULL) {		/* something already available? */
+	if (free_bq != NULL) {		/* something already available? */
+		bp = free_bq;
 		free_bq = bp->next;
 		bp->next = NULL;
-		bp->n2add = accumulate-1;
+		bp->nadded = 0;
 		return(bp);
 	}
 					/* else allocate fresh */
-	bp = (BINQ *)malloc(sizeof(BINQ)+(nmods-1)*sizeof(MODCONT *));
+	bp = (BINQ *)malloc(sizeof(BINQ) + sizeof(MODCONT *)*(nmods-1));
 	if (bp == NULL)
 		goto memerr;
 	for (i = nmods; i--; ) {
@@ -53,7 +59,7 @@ new_binq()
 		/* memset(bp->mca[i]->cbin, 0, sizeof(DCOLOR)*mp->nbins); */
 	}
 	bp->ndx = 0;
-	bp->n2add = accumulate-1;
+	bp->nadded = 0;
 	bp->next = NULL;
 	return(bp);
 memerr:
@@ -89,7 +95,7 @@ free_binq(BINQ *bp)
 
 
 /* Add modifier values to accumulation record in queue and clear */
-void
+static void
 queue_modifiers()
 {
 	MODCONT	*mpin, *mpout;
@@ -105,10 +111,11 @@ queue_modifiers()
 			addcolor(mpout->cbin[j], mpin->cbin[j]);
 		memset(mpin->cbin, 0, sizeof(DCOLOR)*mpin->nbins);
 	}
+	out_bq->nadded++;
 }
 
 
-/* Sum one modifier record into another (doesn't update n2add) */
+/* Sum one modifier record into another (updates nadded) */
 static void
 add_modbin(BINQ *dst, BINQ *src)
 {
@@ -120,6 +127,7 @@ add_modbin(BINQ *dst, BINQ *src)
 		for (j = mpout->nbins; j--; )
 			addcolor(mpout->cbin[j], mpin->cbin[j]);
 	}
+	dst->nadded += src->nadded;
 }
 
 
@@ -139,10 +147,11 @@ queue_output(BINQ *bp)
 		}
 		return;
 	}
-	b_last = NULL;			/* else insert in output queue */
+	b_last = NULL;			/* insert in output queue */
 	for (b_cur = out_bq; b_cur != NULL && b_cur->ndx < bp->ndx;
 				b_cur = b_cur->next)
 		b_last = b_cur;
+
 	if (b_last != NULL) {
 		bp->next = b_cur;
 		b_last->next = bp;
@@ -150,18 +159,17 @@ queue_output(BINQ *bp)
 		bp->next = out_bq;
 		out_bq = bp;
 	}
-	if (accumulate <= 1)		/* no accumulating? */
+	if (accumulate == 1)		/* no accumulation? */
 		return;
 	b_cur = out_bq;			/* else merge accumulation entries */
 	while (b_cur->next != NULL) {
-		if (b_cur->n2add <= 0 ||
+		if (b_cur->nadded >= accumulate ||
 				(b_cur->ndx-1)/accumulate !=
 				(b_cur->next->ndx-1)/accumulate) {
 			b_cur = b_cur->next;
 			continue;
 		}
 		add_modbin(b_cur, b_cur->next);
-		b_cur->n2add--;
 		b_last = b_cur->next;
 		b_cur->next = b_last->next;
 		b_last->next = NULL;
@@ -170,18 +178,34 @@ queue_output(BINQ *bp)
 }
 
 
-/* Get current with output FIFO by producing ready results */
+/* Count number of records ready for output */
 static int
-output_catchup()
+queue_ready()
 {
+	int	nready = 0;
+	BINQ	*bp;
+
+	for (bp = out_bq; bp != NULL && bp->nadded >= accumulate &&
+				bp->ndx == lastdone+nready*accumulate+1;
+				bp = bp->next)
+		++nready;
+
+	return(nready);
+}
+
+
+/* Catch up with output queue by producing ready results */
+static int
+output_catchup(int nmax)
+{
 	int	nout = 0;
 	BINQ	*bp;
 	int	i;
-
-	if (accumulate <= 0)		/* just accumulating? */
-		return(0);
-					/* else output ready results */
-	while (out_bq != NULL && (out_bq->ndx == lastdone+1) & !out_bq->n2add) {
+					/* output ready results */
+	while (out_bq != NULL && out_bq->nadded >= accumulate
+				&& out_bq->ndx == lastdone+1) {
+		if ((nmax > 0) & (nout >= nmax))
+			break;
 		bp = out_bq;			/* pop off first entry */
 		out_bq = bp->next;
 		bp->next = NULL;
@@ -196,9 +220,9 @@ output_catchup()
 }
 
 
-/* Put a zero record in results queue */
+/* Put a zero record in results queue & output */
 void
-zero_record(int ndx)
+put_zero_record(int ndx)
 {
 	BINQ	*bp = new_binq();
 	int	i;
@@ -206,10 +230,32 @@ zero_record(int ndx)
 	for (i = nmods; i--; )
 		memset(bp->mca[i]->cbin, 0, sizeof(DCOLOR)*bp->mca[i]->nbins);
 	bp->ndx = ndx;
+	bp->nadded = 1;
 	queue_output(bp);
+	output_catchup(0);
 }
 
 
+/* Get results from child process and add to queue */
+static void
+queue_results(int k)
+{
+	BINQ	*bq = new_binq();	/* get results holder */
+	int	j;
+
+	bq->ndx = kida[k].r1;
+	bq->nadded = kida[k].nr;
+					/* read from child */
+	for (j = 0; j < nmods; j++)
+		if (fread(bq->mca[j]->cbin, sizeof(DCOLOR), bq->mca[j]->nbins,
+					kida[k].infp) != bq->mca[j]->nbins)
+			error(SYSTEM, "read error from render process");
+			
+	queue_output(bq);		/* put results in output queue */
+	kida[k].nr = 0;			/* mark child as available */
+}
+
+
 /* callback to set output spec to NULL (stdout) */
 static int
 set_stdout(const LUENT *le, void *p)
@@ -223,134 +269,130 @@ set_stdout(const LUENT *le, void *p)
 int
 in_rchild()
 {
-#ifdef _WIN32
-	error(WARNING, "multiprocessing unsupported -- running solo");
-	nproc = 1;
-	return(1);
-#else
-					/* try to fork ourselves */
-	while (nchild < nproc) {
-		int	p0[2], p1[2];
-		int	pid;
-					/* prepare i/o pipes */
-		if (pipe(p0) < 0 || pipe(p1) < 0)
-			error(SYSTEM, "pipe() call failed!");
-		pid = fork();		/* fork parent process */
-		if (pid == 0) {		/* if in child, set up & return true */
-			close(p0[1]); close(p1[0]);
-			dup2(p0[0], 0); close(p0[0]);
-			dup2(p1[1], 1); close(p1[1]);
+	int	rval;
+
+	while (nchild < nproc) {	/* fork until target reached */
+		errno = 0;
+		rval = open_process(&kida[nchild].pr, NULL);
+		if (rval < 0)
+			error(SYSTEM, "open_process() call failed");
+		if (rval == 0) {	/* if in child, set up & return true */
+			lu_doall(&modconttab, &set_stdout, NULL);
+			lu_done(&ofiletab);
+			while (nchild--) {	/* don't share other pipes */
+				close(kida[nchild].pr.w);
+				fclose(kida[nchild].infp);
+			}
 			inpfmt = (sizeof(RREAL)==sizeof(double)) ? 'd' : 'f';
 			outfmt = 'd';
 			header = 0;
-			waitflush = xres = 1;
 			yres = 0;
 			raysleft = 0;
-			account = accumulate = 1;
-			lu_doall(&modconttab, set_stdout, NULL);
-			nchild = -1;
-			return(1);	/* child return value */
+			if (accumulate == 1) {
+				waitflush = xres = 1;
+				account = accumulate = 1;
+			} else {	/* parent controls accumulation */
+				waitflush = xres = 0;
+				account = accumulate = 0;
+			}
+			return(1);	/* return "true" in child */
 		}
-		if (pid < 0)
-			error(SYSTEM, "fork() call failed!");
-					/* connect our pipes */
-		close(p0[0]); close(p1[1]);
-		kida[nchild].r = p1[0];
-		kida[nchild].w = p0[1];
-		kida[nchild].pid = pid;
-		kida[nchild].running = -1;
-		inq_fp[nchild] = fdopen(p1[0], "rb");
-		if (inq_fp[nchild] == NULL)
+		if (rval != PIPE_BUF)
+			error(CONSISTENCY, "bad value from open_process()");
+					/* connect to child's output */
+		kida[nchild].infp = fdopen(kida[nchild].pr.r, "rb");
+		if (kida[nchild].infp == NULL)
 			error(SYSTEM, "out of memory in in_rchild()");
-		++nchild;
-	}
-	return(0);			/* parent return value */
+#ifdef getc_unlocked
+		flockfile(kida[nchild].infp);	/* avoid mutex overhead */
 #endif
+		kida[nchild++].nr = 0;	/* mark as available */
+	}
+	return(0);			/* return "false" in parent */
 }
 
 
 /* Close child processes */
 void
-end_children()
+end_children(int immed)
 {
 	int	status;
 	
-	while (nchild-- > 0) {
-		kida[nchild].r = -1;	/* close(-1) error is ignored */
-		if ((status = close_process(&kida[nchild])) > 0) {
+	while (nchild > 0) {
+		nchild--;
+#ifdef SIGKILL
+		if (immed)		/* error mode -- quick exit */
+			kill(kida[nchild].pr.pid, SIGKILL);
+#endif
+		if ((status = close_process(&kida[nchild].pr)) > 0 && !immed) {
 			sprintf(errmsg,
 				"rendering process returned bad status (%d)",
 					status);
 			error(WARNING, errmsg);
 		}
-		fclose(inq_fp[nchild]);	/* performs actual close() */
+		fclose(kida[nchild].infp);
 	}
 }
 
 
-/* Wait for the next available child, managing output queue as well */
+/* Wait for the next available child, managing output queue simultaneously */
 static int
-next_child_nq(int force_wait)
+next_child_nq(int flushing)
 {
 	static struct timeval	polling;
-	struct timeval		*pmode = force_wait | (accumulate <= 0) ?
-					(struct timeval *)NULL : &polling;
+	struct timeval		*pmode;
 	fd_set			readset, errset;
-	int			i, j, n, nr;
+	int			i, n, nr, nqr;
 
-	if (!force_wait)		/* see if there's one free */
+	if (!flushing)			/* see if there's one free */
 		for (i = nchild; i--; )
-			if (kida[i].running < 0)
+			if (!kida[i].nr)
 				return(i);
+
+	nqr = queue_ready();		/* choose blocking mode or polling */
+	if ((nqr > 0) & !flushing)
+		pmode = &polling;
+	else
+		pmode = NULL;
+tryagain:				/* catch up with output? */
+	if (pmode == &polling) {
+		if (nqr > nchild)	/* don't get too far behind */
+			nqr -= output_catchup(nqr-nchild);
+	} else if (nqr > 0)		/* clear output before blocking */
+		nqr -= output_catchup(0);
 					/* prepare select() call */
 	FD_ZERO(&readset); FD_ZERO(&errset);
 	n = nr = 0;
 	for (i = nchild; i--; ) {
-		if (kida[i].running > 0) {
-			FD_SET(kida[i].r, &readset);
+		if (kida[i].nr) {
+			FD_SET(kida[i].pr.r, &readset);
 			++nr;
 		}
-		FD_SET(kida[i].r, &errset);
-		if (kida[i].r >= n)
-			n = kida[i].r + 1;
+		FD_SET(kida[i].pr.r, &errset);
+		if (kida[i].pr.r >= n)
+			n = kida[i].pr.r + 1;
 	}
-	if (!nr)			/* nothing going on */
+	if (!nr)			/* nothing to wait for? */
 		return(-1);
-tryagain:
-	if (pmode == NULL)		/* about to block, so catch up */
-		output_catchup();
 	if ((nr > 1) | (pmode == &polling)) {
 		errno = 0;
 		nr = select(n, &readset, NULL, &errset, pmode);
-		if (!nr & (pmode == &polling)) {
+		if (!nr) {
 			pmode = NULL;	/* try again, blocking this time */
 			goto tryagain;
 		}
-		if (nr <= 0)
-			error(SYSTEM, "select call error in next_child_nq()");
+		if (nr < 0)
+			error(SYSTEM, "select() error in next_child_nq()");
 	} else
 		FD_ZERO(&errset);
 	n = -1;				/* read results from child(ren) */
 	for (i = nchild; i--; ) {
-		BINQ	*bq;
-		if (FD_ISSET(kida[i].r, &errset))
+		if (FD_ISSET(kida[i].pr.r, &errset))
 			error(USER, "rendering process died");
-		if (!FD_ISSET(kida[i].r, &readset))
-			continue;
-		bq = new_binq();	/* get results holder */
-		bq->ndx = kida[i].running;
-					/* read from child */
-		for (j = 0; j < nmods; j++) {
-			n = bq->mca[j]->nbins;
-			nr = fread(bq->mca[j]->cbin,sizeof(DCOLOR),n,inq_fp[i]);
-			if (nr != n)
-				error(SYSTEM, "read error from render process");
-		}
-		queue_output(bq);	/* put results in output queue */
-		kida[i].running = -1;	/* mark child as available */
-		n = i;
+		if (FD_ISSET(kida[i].pr.r, &readset))
+			queue_results(n = i);
 	}
-	return(n);			/* last available child */
+	return(n);			/* first available child */
 }
 
 
@@ -358,56 +400,161 @@ tryagain:
 void
 parental_loop()
 {
+	const int	qlimit = (accumulate == 1) ? 1 : MAXIQ-1;
+	int		ninq = 0;
+	FVECT		orgdir[2*MAXIQ];
+	int		i, n;
+					/* load rays from stdin & process */
+#ifdef getc_unlocked
+	flockfile(stdin);		/* avoid lock/unlock overhead */
+#endif
+	while (getvec(orgdir[2*ninq]) == 0 && getvec(orgdir[2*ninq+1]) == 0) {
+		const int	zero_ray = orgdir[2*ninq+1][0] == 0.0 &&
+						(orgdir[2*ninq+1][1] == 0.0) &
+						(orgdir[2*ninq+1][2] == 0.0);
+		ninq += !zero_ray;
+				/* Zero ray cannot go in input queue */
+		if (zero_ray ? ninq : ninq >= qlimit ||
+			    lastray/accumulate != (lastray+ninq)/accumulate) {
+			i = next_child_nq(0);		/* manages output */
+			n = ninq;
+			if (accumulate > 1)		/* need terminator? */
+				memset(orgdir[2*n++], 0, sizeof(FVECT)*2);
+			n *= sizeof(FVECT)*2;		/* send assignment */
+			if (writebuf(kida[i].pr.w, (char *)orgdir, n) != n)
+				error(SYSTEM, "pipe write error");
+			kida[i].r1 = lastray+1;
+			lastray += kida[i].nr = ninq;	/* mark as busy */
+			if (lastray < lastdone) {	/* RNUMBER wrapped? */
+				while (next_child_nq(1) >= 0)
+					;
+				lastray -= ninq;
+				lastdone = lastray %= accumulate;
+			}
+			ninq = 0;
+		}
+		if (zero_ray) {				/* put bogus record? */
+			if ((yres <= 0) | (xres <= 1) &&
+					(lastray+1) % accumulate == 0) {
+				while (next_child_nq(1) >= 0)
+					;		/* clear the queue */
+				lastdone = lastray = accumulate-1;
+				waitflush = 1;		/* flush next */
+			}
+			put_zero_record(++lastray);
+		}
+		if (raysleft && !--raysleft)
+			break;				/* preemptive EOI */
+	}
+	while (next_child_nq(1) >= 0)		/* empty results queue */
+		;
+	if (account < accumulate) {
+		error(WARNING, "partial accumulation in final record");
+		free_binq(out_bq);		/* XXX just ignore it */
+		out_bq = NULL;
+	}
+	free_binq(NULL);			/* clean up */
+	lu_done(&ofiletab);
+	if (raysleft)
+		error(USER, "unexpected EOF on input");
+}
+
+
+/* Wait for the next available child by monitoring "to" pipes */
+static int
+next_child_ready()
+{
+	fd_set			writeset, errset;
+	int			i, n;
+
+	for (i = nchild; i--; )		/* see if there's one free first */
+		if (!kida[i].nr)
+			return(i);
+					/* prepare select() call */
+	FD_ZERO(&writeset); FD_ZERO(&errset);
+	n = 0;
+	for (i = nchild; i--; ) {
+		FD_SET(kida[i].pr.w, &writeset);
+		FD_SET(kida[i].pr.r, &errset);
+		if (kida[i].pr.w >= n)
+			n = kida[i].pr.w + 1;
+		if (kida[i].pr.r >= n)
+			n = kida[i].pr.r + 1;
+	}
+	errno = 0;
+	n = select(n, NULL, &writeset, &errset, NULL);
+	if (n < 0)
+		error(SYSTEM, "select() error in next_child_ready()");
+	n = -1;				/* identify waiting child */
+	for (i = nchild; i--; ) {
+		if (FD_ISSET(kida[i].pr.r, &errset))
+			error(USER, "rendering process died");
+		if (FD_ISSET(kida[i].pr.w, &writeset))
+			kida[n = i].nr = 0;
+	}
+	return(n);			/* first available child */
+}
+
+
+/* Modified parental loop for full accumulation mode (-c 0) */
+void
+feeder_loop()
+{
 	static int	ignore_warning_given = 0;
-	FVECT		orgdir[2];
-	double		d;
+	int		ninq = 0;
+	FVECT		orgdir[2*MAXIQ];
+	int		i, n;
 					/* load rays from stdin & process */
 #ifdef getc_unlocked
 	flockfile(stdin);		/* avoid lock/unlock overhead */
 #endif
-	while (getvec(orgdir[0]) == 0 && getvec(orgdir[1]) == 0) {
-		d = normalize(orgdir[1]);
-							/* asking for flush? */
-		if ((d == 0.0) & (accumulate != 1)) {
+	while (getvec(orgdir[2*ninq]) == 0 && getvec(orgdir[2*ninq+1]) == 0) {
+		if (orgdir[2*ninq+1][0] == 0.0 &&	/* asking for flush? */
+				(orgdir[2*ninq+1][1] == 0.0) &
+				(orgdir[2*ninq+1][2] == 0.0)) {
 			if (!ignore_warning_given++)
 				error(WARNING,
 				"dummy ray(s) ignored during accumulation\n");
 			continue;
-		}
-		if ((d == 0.0) | (lastray+1 < lastray)) {
-			while (next_child_nq(1) >= 0)
-				;
-			lastdone = lastray = 0;
-		}
-		if (d == 0.0) {
-			if ((yres <= 0) | (xres <= 0))
-				waitflush = 1;		/* flush right after */
-			zero_record(++lastray);
-		} else {				/* else assign */
-			int	avail = next_child_nq(0);
-			if (writebuf(kida[avail].w, (char *)orgdir,
-					sizeof(FVECT)*2) != sizeof(FVECT)*2)
+		} 
+		if (++ninq >= MAXIQ) {
+			i = next_child_ready();		/* get eager child */
+			n = sizeof(FVECT)*2 * ninq;	/* give assignment */
+			if (writebuf(kida[i].pr.w, (char *)orgdir, n) != n)
 				error(SYSTEM, "pipe write error");
-			kida[avail].running = ++lastray;
+			kida[i].r1 = lastray+1;
+			lastray += kida[i].nr = ninq;
+			if (lastray < lastdone)		/* RNUMBER wrapped? */
+				lastdone = lastray = 0;
+			ninq = 0;
 		}
 		if (raysleft && !--raysleft)
 			break;				/* preemptive EOI */
 	}
-	while (next_child_nq(1) >= 0)		/* empty results queue */
-		;
-						/* output accumulated record */
-	if (accumulate <= 0 || account < accumulate) {
-		int	i;
-		if (account < accumulate) {
-			error(WARNING, "partial accumulation in final record");
-			accumulate -= account;
-		}
-		for (i = 0; i < nmods; i++)
-			mod_output(out_bq->mca[i]);
-		end_record();
+	if (ninq) {				/* polish off input */
+		i = next_child_ready();
+		n = sizeof(FVECT)*2 * ninq;
+		if (writebuf(kida[i].pr.w, (char *)orgdir, n) != n)
+			error(SYSTEM, "pipe write error");
+		kida[i].r1 = lastray+1;
+		lastray += kida[i].nr = ninq;
+		ninq = 0;
 	}
+	memset(orgdir, 0, sizeof(FVECT)*2);	/* get results */
+	for (i = nchild; i--; ) {
+		writebuf(kida[i].pr.w, (char *)orgdir, sizeof(FVECT)*2);
+		queue_results(i);
+	}
+	if (recover)				/* and from before? */
+		queue_modifiers();
+	end_children(0);			/* free up file descriptors */
+	for (i = 0; i < nmods; i++)
+		mod_output(out_bq->mca[i]);	/* output accumulated record */
+	end_record();
+	free_binq(out_bq);			/* clean up */
+	out_bq = NULL;
+	free_binq(NULL);
+	lu_done(&ofiletab);
 	if (raysleft)
 		error(USER, "unexpected EOF on input");
-	free_binq(NULL);			/* clean up */
-	lu_done(&ofiletab);
 }