--- ray/src/rt/persist.c	1996/07/04 09:54:59	2.13
+++ ray/src/rt/persist.c	1997/11/07 12:12:53	2.22
@@ -11,10 +11,9 @@ static char SCCSid[] = "$SunId$ LBL";
 #include "standard.h"
 
 #ifdef F_SETLKW
-
 #include "paths.h"
+#include "selcall.h"
 #include <signal.h>
-#include <sys/types.h>
 #include <sys/stat.h>
 
 #ifndef TIMELIM
@@ -27,10 +26,12 @@ extern int	headismine;	/* boolean true if header belon
 
 extern char	*progname;	/* global program name */
 
+extern char	*errfile;	/* global error file name */
+
 static char	*persistfname = NULL;	/* persist file name */
 static int	persistfd = -1;		/* persist file descriptor */
 
-static char	inpname[TEMPLEN+1], outpname[TEMPLEN+1];
+static char	inpname[TEMPLEN+1], outpname[TEMPLEN+1], errname[TEMPLEN+1];
 
 
 pfdetach()		/* release persist (and header) resources */
@@ -41,6 +42,7 @@ pfdetach()		/* release persist (and header) resources 
 	persistfname = NULL;
 	inpname[0] = '\0';
 	outpname[0] = '\0';
+	errname[0] = '\0';
 	headismine = 0;
 }
 
@@ -55,6 +57,8 @@ pfclean()		/* clean up persist files */
 		unlink(inpname);
 	if (outpname[0])
 		unlink(outpname);
+	if (errname[0])
+		unlink(errname);
 }
 
 
@@ -107,34 +111,46 @@ pfhold()		/* holding pattern for idle rendering proces
 				/* close input and output descriptors */
 	close(fileno(stdin));
 	close(fileno(stdout));
+	if (errfile == NULL)
+		close(fileno(stderr));
 				/* create named pipes for input and output */
 	if (mknod(mktemp(strcpy(inpname,TEMPLATE)), S_IFIFO|0600, 0) < 0)
 		goto createrr;
 	if (mknod(mktemp(strcpy(outpname,TEMPLATE)), S_IFIFO|0600, 0) < 0)
 		goto createrr;
-	sprintf(buf, "%s %d\n%s\n%s\n", progname, getpid(), inpname, outpname);
-	if (lseek(persistfd, 0L, 0) < 0 || ftruncate(persistfd, 0L) < 0)
-		error(SYSTEM, "seek/truncate error on persist file");
+	if (errfile == NULL &&
+		mknod(mktemp(strcpy(errname,TEMPLATE)), S_IFIFO|0600, 0) < 0)
+		goto createrr;
+	sprintf(buf, "%s %d\n%s\n%s\n%s\n", progname, getpid(),
+			inpname, outpname, errname);
 	n = strlen(buf);
 	if (write(persistfd, buf, n) < n)
 		error(SYSTEM, "error writing persist file");
+	lseek(persistfd, 0L, 0);
 				/* wait TIMELIM for someone to signal us */
 	got_io = 0;
 	signal(SIGIO, sig_io);
 	oldalrm = (int (*)())signal(SIGALRM, sig_alrm);
 	alarm(TIMELIM);
-	pflock(0);
+	pflock(0);			/* unlock persist file for attach */
 	while (!got_io)
-		pause();
-	alarm(0);
+		pause();		/* wait for attach */
+	alarm(0);			/* turn off alarm */
 	signal(SIGALRM, oldalrm);
 	signal(SIGIO, SIG_DFL);
-	pflock(1);
+	pflock(1);			/* grab persist file back */
 				/* someone wants us; reopen stdin and stdout */
 	if (freopen(inpname, "r", stdin) == NULL)
 		goto openerr;
 	if (freopen(outpname, "w", stdout) == NULL)
 		goto openerr;
+	sleep(3);		/* give them a chance to open their pipes */
+	if (errname[0]) {
+		if (freopen(errname, "w", stderr) == NULL)
+			goto openerr;
+		unlink(errname);
+		errname[0] = '\0';
+	}
 	unlink(inpname);
 	inpname[0] = '\0';
 	unlink(outpname);
@@ -147,19 +163,28 @@ openerr:
 }
 
 
-io_process()		/* just act as conduits to and from actual process */
+io_process()		/* just act as go-between for actual process */
 {
 	register char	*cp;
 	register int	nr, n;
-	char	buf[512], *pfin, *pfout;
-	int	pid;
-				/* load and close persist file */
-	sleep(5);		/* helps synchronization */
-	nr = read(persistfd, buf, sizeof(buf)-1);
-	pfdetach();
-	if (nr <= 0)
-		error(SYSTEM, "cannot read persist file");
-	buf[nr] = '\0';
+	char	buf[BUFSIZ], *pfin, *pfout, *pferr;
+	int	pid, nfds;
+	int	fdout, fderr = -1;
+	fd_set	readfds, excepfds;
+					/* load persist file */
+	n = 40;
+	while ((nr = read(persistfd, buf, sizeof(buf)-1)) == 0) {
+		if (!n--)
+			error(USER, "unattended persist file?");
+		pflock(0);
+		sleep(15);		/* wait until ready */
+		pflock(1);
+	}
+	if (nr < 0)
+		error(SYSTEM, "error reading persist file");
+	ftruncate(persistfd, 0L);	/* truncate persist file */
+	pfdetach();			/* close & release persist file */
+	buf[nr] = '\0';			/* parse what we got */
 	if ((cp = index(buf, ' ')) == NULL)
 		goto formerr;
 	*cp++ = '\0';
@@ -175,45 +200,104 @@ io_process()		/* just act as conduits to and from actu
 	if ((cp = index(cp, '\n')) == NULL)
 		goto formerr;
 	*cp++ = '\0';
+	pferr = cp;
+	if ((cp = index(cp, '\n')) == NULL)
+		goto formerr;
+	*cp++ = '\0';
 	if (cp-buf != nr)
 		goto formerr;
 	if (strcmp(buf, progname)) {
 		sprintf(errmsg, "persist file for %s, not %s", buf, progname);
 		error(USER, errmsg);
 	}
-				/* wake up rendering process */
+					/* wake up rendering process */
 	if (kill(pid, SIGIO) < 0)
 		error(SYSTEM, "cannot signal rendering process in io_process");
-	pid = fork();		/* fork i/o process */
+					/* fork child feeder process */
+	pid = fork();
 	if (pid < 0)
 		error(SYSTEM, "fork failed in io_process");
-				/* connect to appropriate pipe */
-	if (pid) {			/* parent passes renderer output */
-		close(0);
-		if (open(pfout, O_RDONLY) != 0)
-			error(SYSTEM, "cannot open input pipe in io_process");
-	} else {			/* child passes renderer input */
-		close(1);
-		if (open(pfin, O_WRONLY) != 1)
-			error(SYSTEM, "cannot open output pipe in io_process");
+	if (pid == 0) {			/* feeder loop */
+		int	fdin;
+		close(1);		/* open input pipe */
+		if ((fdin = open(pfin, O_WRONLY)) < 0)
+			error(SYSTEM, "cannot open feed pipe in io_process");
+						/* renderer stdin */
+		while ((nr = read(0, cp=buf, sizeof(buf))) > 0) {
+			do {
+				if ((n = write(fdin, cp, nr)) <= 0)
+					goto writerr;
+				cp += n;
+			} while ((nr -= n) > 0);
+		}
+		if (nr < 0)
+			goto readerr;
+		_exit(0);
 	}
-				/* pass input to output */
-				/* read as much as we can, write all of it */
-	while ((nr = read(0, cp=buf, sizeof(buf))) > 0)
-		do {
-			if ((n = write(1, cp, nr)) <= 0)
-				goto writerr;
-			cp += n;
-		} while ((nr -= n) > 0);
-	if (nr < 0)
-		error(SYSTEM, "read error in io_process");
-	close(0);		/* close input */
-	close(1);		/* close output */
-	if (pid)		/* parent waits for child */
-		wait(0);
-	exit(0);		/* all done, exit (not quit!) */
+	close(0);
+					/* open output pipes, in order */
+	if ((fdout = open(pfout, O_RDONLY)) < 0)
+		error(SYSTEM, "cannot open output pipe in io_process");
+	if (pferr[0] && (fderr = open(pferr, O_RDONLY)) < 0)
+		error(SYSTEM, "cannot open error pipe in io_process");
+	for ( ; ; ) {			/* eater loop */
+		FD_ZERO(&readfds);
+		FD_ZERO(&excepfds);
+		nfds = 0;
+		if (fdout >= 0) {
+			FD_SET(fdout, &readfds);
+			FD_SET(fdout, &excepfds);
+			nfds = fdout+1;
+		}
+		if (fderr >= 0) {
+			FD_SET(fderr, &readfds);
+			FD_SET(fderr, &excepfds);
+			nfds = fderr+1;
+		}
+		if (nfds == 0)
+			break;			/* all done, exit */
+		if (select(nfds, &readfds, NULL, &excepfds, NULL) < 0)
+			error(SYSTEM, "error in select call in io_process");
+						/* renderer stderr */
+		if (fderr >= 0 && (FD_ISSET(fderr, &readfds) ||
+				FD_ISSET(fderr, &excepfds))) {
+			nr = read(fderr, cp=buf, sizeof(buf));
+			if (nr < 0)
+				goto readerr;
+			if (nr == 0) {
+				close(fderr);
+				/* close(2);	don't close stderr! */
+				fderr = -1;
+			} else
+				do {		/* write it all */
+					if ((n = write(2, cp, nr)) <= 0)
+						goto writerr;
+					cp += n;
+				} while ((nr -= n) > 0);
+		}
+						/* renderer stdout */
+		if (fdout >= 0 && (FD_ISSET(fdout, &readfds) ||
+				FD_ISSET(fdout, &excepfds))) {
+			nr = read(fdout, cp=buf, sizeof(buf));
+			if (nr < 0)
+				goto readerr;
+			if (nr == 0) {		/* EOF */
+				close(fdout);
+				close(1);
+				fdout = -1;
+			} else
+				do {		/* write it all */
+					if ((n = write(1, cp, nr)) <= 0)
+						goto writerr;
+					cp += n;
+				} while ((nr -= n) > 0);
+		}
+	}
+	_exit(0);		/* we ought to return renderer error status! */
 formerr:
 	error(USER, "format error in persist file");
+readerr:
+	error(SYSTEM, "read error in io_process");
 writerr:
 	error(SYSTEM, "write error in io_process");
 }