src/rt/rc3.c

#ifndef lint
static const char RCSid[] = "$Id: rc3.c,v 2.20 2015/08/23 00:17:12 greg Exp $";
#endif
/*
 * Accumulate ray contributions for a set of materials
 * Controlling process for multiple children
 */

#include <signal.h>
#include "rcontrib.h"
#include "selcall.h"

#define MAXIQ           (int)(PIPE_BUF/(sizeof(FVECT)*2))

/* Modifier contribution queue (results waiting to be output) */
typedef struct s_binq {
        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;

static BINQ     *out_bq = NULL;         /* output bin queue */
static BINQ     *free_bq = NULL;        /* free queue entries */

static SUBPROC  kidpr[MAXPROCESS];      /* our child processes */

static struct {
        RNUMBER r1;                     /* assigned ray starting index */
        FILE    *infp;                  /* file pointer to read from process */
        int     nr;                     /* number of rays to sum (0 if free) */
} kida[MAXPROCESS];             /* our child process i/o */


/* Get new bin queue entry */
static BINQ *
new_binq()
{
        BINQ    *bp;
        int     i;

        if (free_bq != NULL) {          /* something already available? */
                bp = free_bq;
                free_bq = bp->next;
                bp->next = NULL;
                bp->nadded = 0;
                return(bp);
        }
                                        /* else allocate fresh */
        bp = (BINQ *)malloc(sizeof(BINQ) + sizeof(MODCONT *)*(nmods-1));
        if (bp == NULL)
                goto memerr;
        for (i = nmods; i--; ) {
                MODCONT *mp = (MODCONT *)lu_find(&modconttab,modname[i])->data;
                bp->mca[i] = (MODCONT *)malloc(sizeof(MODCONT) +
                                                sizeof(DCOLOR)*(mp->nbins-1));
                if (bp->mca[i] == NULL)
                        goto memerr;
                memcpy(bp->mca[i], mp, sizeof(MODCONT)-sizeof(DCOLOR));
                /* memset(bp->mca[i]->cbin, 0, sizeof(DCOLOR)*mp->nbins); */
        }
        bp->ndx = 0;
        bp->nadded = 0;
        bp->next = NULL;
        return(bp);
memerr:
        error(SYSTEM, "out of memory in new_binq()");
        return(NULL);
}


/* Free a bin queue entry */
static void
free_binq(BINQ *bp)
{
        int     i;

        if (bp == NULL) {               /* signal to release our free list */
                while ((bp = free_bq) != NULL) {
                        free_bq = bp->next;
                        for (i = nmods; i--; )
                                free(bp->mca[i]);
                                /* Note: we don't own bp->mca[i]->binv */
                        free(bp);
                }
                return;
        }
                                        /* clear sums for next use */
/*      for (i = nmods; i--; )
                memset(bp->mca[i]->cbin, 0, sizeof(DCOLOR)*bp->mca[i]->nbins);
*/
        bp->ndx = 0;
        bp->next = free_bq;             /* push onto free list */
        free_bq = bp;
}


/* Add modifier values to accumulation record in queue and clear */
static void
queue_modifiers()
{
        MODCONT *mpin, *mpout;
        int     i, j;

        if ((accumulate > 0) | (out_bq == NULL))
                error(CONSISTENCY, "bad call to queue_modifiers()");

        for (i = nmods; i--; ) {
                mpin = (MODCONT *)lu_find(&modconttab,modname[i])->data;
                mpout = out_bq->mca[i];
                for (j = mpout->nbins; j--; )
                        addcolor(mpout->cbin[j], mpin->cbin[j]);
                memset(mpin->cbin, 0, sizeof(DCOLOR)*mpin->nbins);
        }
        out_bq->nadded++;
}


/* Sum one modifier record into another (updates nadded) */
static void
add_modbin(BINQ *dst, BINQ *src)
{
        int     i, j;
        
        for (i = nmods; i--; ) {
                MODCONT *mpin = src->mca[i];
                MODCONT *mpout = dst->mca[i];
                for (j = mpout->nbins; j--; )
                        addcolor(mpout->cbin[j], mpin->cbin[j]);
        }
        dst->nadded += src->nadded;
}


/* Queue values for later output */
static void
queue_output(BINQ *bp)
{
        BINQ    *b_last, *b_cur;

        if (accumulate <= 0) {          /* just accumulating? */
                if (out_bq == NULL) {
                        bp->next = NULL;
                        out_bq = bp;
                } else {
                        add_modbin(out_bq, bp);
                        free_binq(bp);
                }
                return;
        }
        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;
        } else {
                bp->next = out_bq;
                out_bq = bp;
        }
        if (accumulate == 1)            /* no accumulation? */
                return;
        b_cur = out_bq;                 /* else merge accumulation entries */
        while (b_cur->next != NULL) {
                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_last = b_cur->next;
                b_cur->next = b_last->next;
                b_last->next = NULL;
                free_binq(b_last);
        }
}


/* Count number of records ready for output */
static int
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;
                                        /* 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;
                for (i = 0; i < nmods; i++)     /* output record */
                        mod_output(bp->mca[i]);
                end_record();
                free_binq(bp);                  /* free this entry */
                lastdone += accumulate;
                ++nout;
        }
        return(nout);
}


/* Put a zero record in results queue & output */
void
put_zero_record(int ndx)
{
        BINQ    *bp = new_binq();
        int     i;

        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)
{
        (*(MODCONT *)le->data).outspec = NULL;
        return(0);
}


/* Start child processes if we can (call only once in parent!) */
int
in_rchild()
{
        int     rval;

        while (nchild < nproc) {        /* fork until target reached */
                errno = 0;
                rval = open_process(&kidpr[nchild], 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(kidpr[nchild].w);
                                fclose(kida[nchild].infp);
                        }
                        inpfmt = (sizeof(RREAL)==sizeof(double)) ? 'd' : 'f';
                        outfmt = 'd';
                        header = 0;
                        yres = 0;
                        raysleft = 0;
                        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 (rval != PIPE_BUF)
                        error(CONSISTENCY, "bad value from open_process()");
                                        /* connect to child's output */
                kida[nchild].infp = fdopen(kidpr[nchild].r, "rb");
                if (kida[nchild].infp == NULL)
                        error(SYSTEM, "out of memory in in_rchild()");
                kida[nchild++].nr = 0;  /* mark as available */
        }
#ifdef getc_unlocked
        for (rval = nchild; rval--; )   /* avoid mutex overhead */
                flockfile(kida[rval].infp);
#endif
        return(0);                      /* return "false" in parent */
}


/* Close child processes */
void
end_children(int immed)
{
        int     i;

#ifdef SIGKILL                          /* error mode -- quick exit */
        for (i = nchild*immed; i-- > 0; )
                kill(kidpr[nchild].pid, SIGKILL);
#endif
        if ((i = close_processes(kidpr, nchild)) > 0 && !immed) {
                sprintf(errmsg, "rendering process returned bad status (%d)",
                                        i);
                        error(WARNING, errmsg);
        }
        while (nchild-- > 0)
                fclose(kida[nchild].infp);
}


/* Wait for the next available child, managing output queue simultaneously */
static int
next_child_nq(int flushing)
{
        static struct timeval   polling;
        struct timeval          *pmode;
        fd_set                  readset, errset;
        int                     i, n, nr, nqr;

        if (!flushing)                  /* see if there's one free */
                for (i = nchild; i--; )
                        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].nr) {
                        FD_SET(kidpr[i].r, &readset);
                        ++nr;
                }
                FD_SET(kidpr[i].r, &errset);
                if (kidpr[i].r >= n)
                        n = kidpr[i].r + 1;
        }
        if (!nr)                        /* nothing to wait for? */
                return(-1);
        if ((nr > 1) | (pmode == &polling)) {
                errno = 0;
                nr = select(n, &readset, NULL, &errset, pmode);
                if (!nr) {
                        pmode = NULL;   /* try again, blocking this time */
                        goto tryagain;
                }
                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--; ) {
                if (FD_ISSET(kidpr[i].r, &errset))
                        error(USER, "rendering process died");
                if (FD_ISSET(kidpr[i].r, &readset))
                        queue_results(n = i);
        }
        return(n);                      /* first available child */
}


/* Run parental oversight loop */
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(kidpr[i].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(kidpr[i].w, &writeset);
                FD_SET(kidpr[i].r, &errset);
                if (kidpr[i].w >= n)
                        n = kidpr[i].w + 1;
                if (kidpr[i].r >= n)
                        n = kidpr[i].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(kidpr[i].r, &errset))
                        error(USER, "rendering process died");
                if (FD_ISSET(kidpr[i].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;
        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) {
                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 (++ninq >= MAXIQ) {
                        i = next_child_ready();         /* get eager child */
                        n = sizeof(FVECT)*2 * ninq;     /* give assignment */
                        if (writebuf(kidpr[i].w, (char *)orgdir, n) != n)
                                error(SYSTEM, "pipe write error");
                        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 */
        }
        if (ninq) {                             /* polish off input */
                i = next_child_ready();
                n = sizeof(FVECT)*2 * ninq;
                if (writebuf(kidpr[i].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(kidpr[i].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");
}
Revision:	2.21
Committed:	Fri Mar 4 02:48:14 2016 UTC (8 years, 2 months ago) by greg
Content type:	text/plain
Branch:	MAIN
Changes since 2.20:	+35 -37 lines
Log Message:	Made quitting rvu, rholo and rcontrib quicker with multiple processes on Unix
#	User	Rev	Content
1	greg	2.1	#ifndef lint
2	greg	2.21	static const char RCSid[] = "$Id: rc3.c,v 2.20 2015/08/23 00:17:12 greg Exp $";
3	greg	2.1	#endif
4			/*
5			* Accumulate ray contributions for a set of materials
6			* Controlling process for multiple children
7			*/
8
9	greg	2.14	#include <signal.h>
10	greg	2.1	#include "rcontrib.h"
11			#include "selcall.h"
12
13	greg	2.10	#define MAXIQ (int)(PIPE_BUF/(sizeof(FVECT)*2))
14
15	greg	2.1	/* Modifier contribution queue (results waiting to be output) */
16			typedef struct s_binq {
17	greg	2.6	RNUMBER ndx; /* index for this entry */
18			RNUMBER nadded; /* accumulated so far */
19	greg	2.1	struct s_binq next; / next in queue */
20			MODCONT mca[1]; / contrib. array (extends struct) */
21			} BINQ;
22
23			static BINQ out_bq = NULL; / output bin queue */
24			static BINQ free_bq = NULL; / free queue entries */
25
26	greg	2.21	static SUBPROC kidpr[MAXPROCESS]; /* our child processes */
27
28	greg	2.6	static struct {
29			RNUMBER r1; /* assigned ray starting index */
30			FILE infp; / file pointer to read from process */
31	greg	2.10	int nr; /* number of rays to sum (0 if free) */
32	greg	2.21	} kida[MAXPROCESS]; /* our child process i/o */
33	greg	2.1
34
35	greg	2.4	/* Get new bin queue entry */
36	greg	2.1	static BINQ *
37			new_binq()
38			{
39	greg	2.4	BINQ *bp;
40	greg	2.1	int i;
41
42	greg	2.4	if (free_bq != NULL) { /* something already available? */
43			bp = free_bq;
44	greg	2.1	free_bq = bp->next;
45			bp->next = NULL;
46	greg	2.6	bp->nadded = 0;
47	greg	2.1	return(bp);
48			}
49			/* else allocate fresh */
50	greg	2.4	bp = (BINQ )malloc(sizeof(BINQ) + sizeof(MODCONT )*(nmods-1));
51	greg	2.1	if (bp == NULL)
52			goto memerr;
53			for (i = nmods; i--; ) {
54			MODCONT mp = (MODCONT )lu_find(&modconttab,modname[i])->data;
55			bp->mca[i] = (MODCONT *)malloc(sizeof(MODCONT) +
56			sizeof(DCOLOR)*(mp->nbins-1));
57			if (bp->mca[i] == NULL)
58			goto memerr;
59			memcpy(bp->mca[i], mp, sizeof(MODCONT)-sizeof(DCOLOR));
60			/* memset(bp->mca[i]->cbin, 0, sizeof(DCOLOR)mp->nbins); /
61			}
62			bp->ndx = 0;
63	greg	2.6	bp->nadded = 0;
64	greg	2.1	bp->next = NULL;
65			return(bp);
66			memerr:
67			error(SYSTEM, "out of memory in new_binq()");
68			return(NULL);
69			}
70
71
72			/* Free a bin queue entry */
73			static void
74			free_binq(BINQ *bp)
75			{
76			int i;
77
78			if (bp == NULL) { /* signal to release our free list */
79			while ((bp = free_bq) != NULL) {
80			free_bq = bp->next;
81			for (i = nmods; i--; )
82			free(bp->mca[i]);
83			/* Note: we don't own bp->mca[i]->binv */
84			free(bp);
85			}
86			return;
87			}
88			/* clear sums for next use */
89			/* for (i = nmods; i--; )
90			memset(bp->mca[i]->cbin, 0, sizeof(DCOLOR)*bp->mca[i]->nbins);
91			*/
92			bp->ndx = 0;
93			bp->next = free_bq; /* push onto free list */
94			free_bq = bp;
95			}
96
97
98			/* Add modifier values to accumulation record in queue and clear */
99	greg	2.10	static void
100	greg	2.1	queue_modifiers()
101			{
102			MODCONT mpin, mpout;
103			int i, j;
104
105			if ((accumulate > 0) \| (out_bq == NULL))
106			error(CONSISTENCY, "bad call to queue_modifiers()");
107
108			for (i = nmods; i--; ) {
109			mpin = (MODCONT *)lu_find(&modconttab,modname[i])->data;
110			mpout = out_bq->mca[i];
111			for (j = mpout->nbins; j--; )
112			addcolor(mpout->cbin[j], mpin->cbin[j]);
113			memset(mpin->cbin, 0, sizeof(DCOLOR)*mpin->nbins);
114			}
115	greg	2.5	out_bq->nadded++;
116	greg	2.1	}
117
118
119	greg	2.4	/* Sum one modifier record into another (updates nadded) */
120	greg	2.1	static void
121			add_modbin(BINQ dst, BINQ src)
122			{
123			int i, j;
124
125			for (i = nmods; i--; ) {
126			MODCONT *mpin = src->mca[i];
127			MODCONT *mpout = dst->mca[i];
128			for (j = mpout->nbins; j--; )
129			addcolor(mpout->cbin[j], mpin->cbin[j]);
130			}
131	greg	2.4	dst->nadded += src->nadded;
132	greg	2.1	}
133
134
135	greg	2.2	/* Queue values for later output */
136			static void
137	greg	2.1	queue_output(BINQ *bp)
138			{
139			BINQ b_last, b_cur;
140
141			if (accumulate <= 0) { /* just accumulating? */
142			if (out_bq == NULL) {
143			bp->next = NULL;
144			out_bq = bp;
145			} else {
146			add_modbin(out_bq, bp);
147			free_binq(bp);
148			}
149	greg	2.2	return;
150	greg	2.1	}
151	greg	2.10	b_last = NULL; /* insert in output queue */
152	greg	2.1	for (b_cur = out_bq; b_cur != NULL && b_cur->ndx < bp->ndx;
153			b_cur = b_cur->next)
154			b_last = b_cur;
155	greg	2.4
156	greg	2.1	if (b_last != NULL) {
157			bp->next = b_cur;
158			b_last->next = bp;
159			} else {
160			bp->next = out_bq;
161			out_bq = bp;
162			}
163	greg	2.3	if (accumulate == 1) /* no accumulation? */
164	greg	2.2	return;
165			b_cur = out_bq; /* else merge accumulation entries */
166			while (b_cur->next != NULL) {
167	greg	2.4	if (b_cur->nadded >= accumulate \|\|
168	greg	2.2	(b_cur->ndx-1)/accumulate !=
169			(b_cur->next->ndx-1)/accumulate) {
170			b_cur = b_cur->next;
171			continue;
172	greg	2.1	}
173	greg	2.2	add_modbin(b_cur, b_cur->next);
174			b_last = b_cur->next;
175			b_cur->next = b_last->next;
176			b_last->next = NULL;
177			free_binq(b_last);
178	greg	2.1	}
179	greg	2.2	}
180
181
182	greg	2.4	/* Count number of records ready for output */
183			static int
184			queue_ready()
185			{
186			int nready = 0;
187			BINQ *bp;
188
189			for (bp = out_bq; bp != NULL && bp->nadded >= accumulate &&
190			bp->ndx == lastdone+nready*accumulate+1;
191			bp = bp->next)
192			++nready;
193
194			return(nready);
195			}
196
197
198			/* Catch up with output queue by producing ready results */
199	greg	2.2	static int
200	greg	2.4	output_catchup(int nmax)
201	greg	2.2	{
202			int nout = 0;
203			BINQ *bp;
204			int i;
205	greg	2.10	/* output ready results */
206	greg	2.4	while (out_bq != NULL && out_bq->nadded >= accumulate
207			&& out_bq->ndx == lastdone+1) {
208			if ((nmax > 0) & (nout >= nmax))
209			break;
210	greg	2.2	bp = out_bq; /* pop off first entry */
211			out_bq = bp->next;
212			bp->next = NULL;
213	greg	2.1	for (i = 0; i < nmods; i++) /* output record */
214	greg	2.2	mod_output(bp->mca[i]);
215	greg	2.1	end_record();
216	greg	2.2	free_binq(bp); /* free this entry */
217	greg	2.1	lastdone += accumulate;
218			++nout;
219			}
220			return(nout);
221			}
222
223
224	greg	2.3	/* Put a zero record in results queue & output */
225	greg	2.1	void
226	greg	2.3	put_zero_record(int ndx)
227	greg	2.1	{
228			BINQ *bp = new_binq();
229			int i;
230
231			for (i = nmods; i--; )
232			memset(bp->mca[i]->cbin, 0, sizeof(DCOLOR)*bp->mca[i]->nbins);
233			bp->ndx = ndx;
234	greg	2.6	bp->nadded = 1;
235	greg	2.1	queue_output(bp);
236	greg	2.4	output_catchup(0);
237	greg	2.1	}
238
239
240	greg	2.6	/* Get results from child process and add to queue */
241			static void
242			queue_results(int k)
243			{
244			BINQ bq = new_binq(); / get results holder */
245			int j;
246
247			bq->ndx = kida[k].r1;
248			bq->nadded = kida[k].nr;
249			/* read from child */
250			for (j = 0; j < nmods; j++)
251			if (fread(bq->mca[j]->cbin, sizeof(DCOLOR), bq->mca[j]->nbins,
252			kida[k].infp) != bq->mca[j]->nbins)
253			error(SYSTEM, "read error from render process");
254
255			queue_output(bq); /* put results in output queue */
256			kida[k].nr = 0; /* mark child as available */
257			}
258
259
260	greg	2.1	/* callback to set output spec to NULL (stdout) */
261			static int
262			set_stdout(const LUENT le, void p)
263			{
264			((MODCONT )le->data).outspec = NULL;
265			return(0);
266			}
267
268
269	greg	2.20	/* Start child processes if we can (call only once in parent!) */
270	greg	2.1	int
271			in_rchild()
272			{
273	greg	2.9	int rval;
274
275			while (nchild < nproc) { /* fork until target reached */
276	greg	2.3	errno = 0;
277	greg	2.21	rval = open_process(&kidpr[nchild], NULL);
278	greg	2.9	if (rval < 0)
279			error(SYSTEM, "open_process() call failed");
280			if (rval == 0) { /* if in child, set up & return true */
281	greg	2.18	lu_doall(&modconttab, &set_stdout, NULL);
282	greg	2.4	lu_done(&ofiletab);
283	greg	2.5	while (nchild--) { /* don't share other pipes */
284	greg	2.21	close(kidpr[nchild].w);
285	greg	2.6	fclose(kida[nchild].infp);
286	greg	2.4	}
287	greg	2.1	inpfmt = (sizeof(RREAL)==sizeof(double)) ? 'd' : 'f';
288			outfmt = 'd';
289			header = 0;
290			yres = 0;
291			raysleft = 0;
292	greg	2.6	if (accumulate == 1) {
293			waitflush = xres = 1;
294			account = accumulate = 1;
295			} else { /* parent controls accumulation */
296			waitflush = xres = 0;
297			account = accumulate = 0;
298			}
299	greg	2.9	return(1); /* return "true" in child */
300	greg	2.1	}
301	greg	2.9	if (rval != PIPE_BUF)
302			error(CONSISTENCY, "bad value from open_process()");
303			/* connect to child's output */
304	greg	2.21	kida[nchild].infp = fdopen(kidpr[nchild].r, "rb");
305	greg	2.6	if (kida[nchild].infp == NULL)
306	greg	2.2	error(SYSTEM, "out of memory in in_rchild()");
307	greg	2.6	kida[nchild++].nr = 0; /* mark as available */
308	greg	2.1	}
309	greg	2.20	#ifdef getc_unlocked
310			for (rval = nchild; rval--; ) /* avoid mutex overhead */
311			flockfile(kida[rval].infp);
312			#endif
313	greg	2.9	return(0); /* return "false" in parent */
314	greg	2.1	}
315
316
317			/* Close child processes */
318			void
319	greg	2.12	end_children(int immed)
320	greg	2.1	{
321	greg	2.21	int i;
322
323			#ifdef SIGKILL /* error mode -- quick exit */
324			for (i = nchild*immed; i-- > 0; )
325			kill(kidpr[nchild].pid, SIGKILL);
326	greg	2.15	#endif
327	greg	2.21	if ((i = close_processes(kidpr, nchild)) > 0 && !immed) {
328			sprintf(errmsg, "rendering process returned bad status (%d)",
329			i);
330	greg	2.1	error(WARNING, errmsg);
331	greg	2.21	}
332			while (nchild-- > 0)
333	greg	2.9	fclose(kida[nchild].infp);
334	greg	2.1	}
335
336
337	greg	2.5	/* Wait for the next available child, managing output queue simultaneously */
338	greg	2.1	static int
339	greg	2.5	next_child_nq(int flushing)
340	greg	2.1	{
341	greg	2.2	static struct timeval polling;
342	greg	2.4	struct timeval *pmode;
343	greg	2.2	fd_set readset, errset;
344	greg	2.6	int i, n, nr, nqr;
345	greg	2.1
346	greg	2.5	if (!flushing) /* see if there's one free */
347	greg	2.1	for (i = nchild; i--; )
348	greg	2.6	if (!kida[i].nr)
349	greg	2.1	return(i);
350	greg	2.4
351	greg	2.5	nqr = queue_ready(); /* choose blocking mode or polling */
352			if ((nqr > 0) & !flushing)
353			pmode = &polling;
354			else
355	greg	2.4	pmode = NULL;
356	greg	2.5	tryagain: /* catch up with output? */
357			if (pmode == &polling) {
358			if (nqr > nchild) /* don't get too far behind */
359			nqr -= output_catchup(nqr-nchild);
360			} else if (nqr > 0) /* clear output before blocking */
361			nqr -= output_catchup(0);
362	greg	2.1	/* prepare select() call */
363			FD_ZERO(&readset); FD_ZERO(&errset);
364			n = nr = 0;
365			for (i = nchild; i--; ) {
366	greg	2.6	if (kida[i].nr) {
367	greg	2.21	FD_SET(kidpr[i].r, &readset);
368	greg	2.1	++nr;
369			}
370	greg	2.21	FD_SET(kidpr[i].r, &errset);
371			if (kidpr[i].r >= n)
372			n = kidpr[i].r + 1;
373	greg	2.1	}
374	greg	2.3	if (!nr) /* nothing to wait for? */
375			return(-1);
376	greg	2.2	if ((nr > 1) \| (pmode == &polling)) {
377	greg	2.1	errno = 0;
378	greg	2.5	nr = select(n, &readset, NULL, &errset, pmode);
379			if (!nr) {
380	greg	2.2	pmode = NULL; /* try again, blocking this time */
381			goto tryagain;
382			}
383	greg	2.5	if (nr < 0)
384	greg	2.3	error(SYSTEM, "select() error in next_child_nq()");
385	greg	2.1	} else
386			FD_ZERO(&errset);
387			n = -1; /* read results from child(ren) */
388			for (i = nchild; i--; ) {
389	greg	2.21	if (FD_ISSET(kidpr[i].r, &errset))
390	greg	2.1	error(USER, "rendering process died");
391	greg	2.21	if (FD_ISSET(kidpr[i].r, &readset))
392	greg	2.6	queue_results(n = i);
393	greg	2.1	}
394	greg	2.3	return(n); /* first available child */
395	greg	2.1	}
396
397
398			/* Run parental oversight loop */
399			void
400			parental_loop()
401			{
402	greg	2.17	const int qlimit = (accumulate == 1) ? 1 : MAXIQ-1;
403	greg	2.6	int ninq = 0;
404			FVECT orgdir[2*MAXIQ];
405			int i, n;
406	greg	2.1	/* load rays from stdin & process */
407			#ifdef getc_unlocked
408			flockfile(stdin); /* avoid lock/unlock overhead */
409			#endif
410	greg	2.6	while (getvec(orgdir[2ninq]) == 0 && getvec(orgdir[2ninq+1]) == 0) {
411	greg	2.18	const int zero_ray = orgdir[2*ninq+1][0] == 0.0 &&
412			(orgdir[2*ninq+1][1] == 0.0) &
413			(orgdir[2*ninq+1][2] == 0.0);
414			ninq += !zero_ray;
415			/* Zero ray cannot go in input queue */
416			if (zero_ray ? ninq : ninq >= qlimit \|\|
417	greg	2.6	lastray/accumulate != (lastray+ninq)/accumulate) {
418	greg	2.5	i = next_child_nq(0); /* manages output */
419	greg	2.6	n = ninq;
420	greg	2.18	if (accumulate > 1) /* need terminator? */
421	greg	2.6	memset(orgdir[2n++], 0, sizeof(FVECT)2);
422			n = sizeof(FVECT)2; /* send assignment */
423	greg	2.21	if (writebuf(kidpr[i].w, (char *)orgdir, n) != n)
424	greg	2.1	error(SYSTEM, "pipe write error");
425	greg	2.6	kida[i].r1 = lastray+1;
426			lastray += kida[i].nr = ninq; /* mark as busy */
427			if (lastray < lastdone) { /* RNUMBER wrapped? */
428			while (next_child_nq(1) >= 0)
429			;
430	greg	2.17	lastray -= ninq;
431			lastdone = lastray %= accumulate;
432	greg	2.6	}
433	greg	2.17	ninq = 0;
434	greg	2.1	}
435	greg	2.18	if (zero_ray) { /* put bogus record? */
436			if ((yres <= 0) \| (xres <= 1) &&
437			(lastray+1) % accumulate == 0) {
438			while (next_child_nq(1) >= 0)
439			; /* clear the queue */
440			lastdone = lastray = accumulate-1;
441			waitflush = 1; /* flush next */
442			}
443			put_zero_record(++lastray);
444			}
445	greg	2.1	if (raysleft && !--raysleft)
446			break; /* preemptive EOI */
447			}
448			while (next_child_nq(1) >= 0) /* empty results queue */
449			;
450	greg	2.10	if (account < accumulate) {
451			error(WARNING, "partial accumulation in final record");
452			free_binq(out_bq); /* XXX just ignore it */
453	greg	2.3	out_bq = NULL;
454	greg	2.1	}
455	greg	2.10	free_binq(NULL); /* clean up */
456			lu_done(&ofiletab);
457	greg	2.1	if (raysleft)
458			error(USER, "unexpected EOF on input");
459	greg	2.10	}
460
461
462			/* Wait for the next available child by monitoring "to" pipes */
463			static int
464			next_child_ready()
465			{
466			fd_set writeset, errset;
467	greg	2.11	int i, n;
468	greg	2.10
469			for (i = nchild; i--; ) /* see if there's one free first */
470			if (!kida[i].nr)
471			return(i);
472			/* prepare select() call */
473			FD_ZERO(&writeset); FD_ZERO(&errset);
474			n = 0;
475			for (i = nchild; i--; ) {
476	greg	2.21	FD_SET(kidpr[i].w, &writeset);
477			FD_SET(kidpr[i].r, &errset);
478			if (kidpr[i].w >= n)
479			n = kidpr[i].w + 1;
480			if (kidpr[i].r >= n)
481			n = kidpr[i].r + 1;
482	greg	2.10	}
483			errno = 0;
484			n = select(n, NULL, &writeset, &errset, NULL);
485			if (n < 0)
486			error(SYSTEM, "select() error in next_child_ready()");
487			n = -1; /* identify waiting child */
488			for (i = nchild; i--; ) {
489	greg	2.21	if (FD_ISSET(kidpr[i].r, &errset))
490	greg	2.10	error(USER, "rendering process died");
491	greg	2.21	if (FD_ISSET(kidpr[i].w, &writeset))
492	greg	2.10	kida[n = i].nr = 0;
493			}
494			return(n); /* first available child */
495			}
496
497
498			/* Modified parental loop for full accumulation mode (-c 0) */
499			void
500			feeder_loop()
501			{
502			static int ignore_warning_given = 0;
503			int ninq = 0;
504			FVECT orgdir[2*MAXIQ];
505			int i, n;
506			/* load rays from stdin & process */
507			#ifdef getc_unlocked
508			flockfile(stdin); /* avoid lock/unlock overhead */
509			#endif
510			while (getvec(orgdir[2ninq]) == 0 && getvec(orgdir[2ninq+1]) == 0) {
511			if (orgdir[2ninq+1][0] == 0.0 && / asking for flush? */
512			(orgdir[2*ninq+1][1] == 0.0) &
513			(orgdir[2*ninq+1][2] == 0.0)) {
514			if (!ignore_warning_given++)
515			error(WARNING,
516			"dummy ray(s) ignored during accumulation\n");
517			continue;
518			}
519			if (++ninq >= MAXIQ) {
520			i = next_child_ready(); /* get eager child */
521			n = sizeof(FVECT)2 ninq; /* give assignment */
522	greg	2.21	if (writebuf(kidpr[i].w, (char *)orgdir, n) != n)
523	greg	2.10	error(SYSTEM, "pipe write error");
524			kida[i].r1 = lastray+1;
525			lastray += kida[i].nr = ninq;
526			if (lastray < lastdone) /* RNUMBER wrapped? */
527			lastdone = lastray = 0;
528	greg	2.18	ninq = 0;
529	greg	2.10	}
530			if (raysleft && !--raysleft)
531			break; /* preemptive EOI */
532			}
533			if (ninq) { /* polish off input */
534			i = next_child_ready();
535			n = sizeof(FVECT)2 ninq;
536	greg	2.21	if (writebuf(kidpr[i].w, (char *)orgdir, n) != n)
537	greg	2.10	error(SYSTEM, "pipe write error");
538			kida[i].r1 = lastray+1;
539			lastray += kida[i].nr = ninq;
540			ninq = 0;
541			}
542	greg	2.13	memset(orgdir, 0, sizeof(FVECT)2); / get results */
543			for (i = nchild; i--; ) {
544	greg	2.21	writebuf(kidpr[i].w, (char )orgdir, sizeof(FVECT)2);
545	greg	2.10	queue_results(i);
546			}
547			if (recover) /* and from before? */
548			queue_modifiers();
549	greg	2.12	end_children(0); /* free up file descriptors */
550	greg	2.10	for (i = 0; i < nmods; i++)
551			mod_output(out_bq->mca[i]); /* output accumulated record */
552			end_record();
553			free_binq(out_bq); /* clean up */
554			out_bq = NULL;
555			free_binq(NULL);
556	greg	2.1	lu_done(&ofiletab);
557	greg	2.10	if (raysleft)
558			error(USER, "unexpected EOF on input");
559	greg	2.1	}