src/util/rpiece.c

/* Copyright (c) 1992 Regents of the University of California */

#ifndef lint
static char SCCSid[] = "$SunId$ LBL";
#endif

/*
 * Generate sections of a picture.
 */
 
#include "standard.h"
#include <fcntl.h>
#include <signal.h>
#include "color.h"
#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  *pbuf;
                                /* our view parameters */
VIEW  ourview = STDVIEW;
double  pixaspect = 1.0;
int  hres = 512, vres = 512, hmult = 2, vmult = 2;
                                /* output file */
char  *outfile = NULL;
int  outfd;
long  scanorig;
int  syncfd = -1;               /* lock file descriptor */
int  nforked = 0;

char  *progname;
int  verbose = 0;

extern long  lseek(), ftell();

int  gotalrm = 0;
int  onalrm() { gotalrm++; }


main(argc, argv)
int  argc;
char  *argv[];
{
        register int  i, rval;
        
        progname = argv[0];
        for (i = 1; i < argc; i++) {
                if (argv[i][0] == '-')
                        switch (argv[i][1]) {
                        case 'v':
                                switch (argv[i][2]) {
                                case '\0':      /* verbose option */
                                        verbose = !verbose;
                                        continue;
                                case 'f':       /* view file */
                                        if (viewfile(argv[++i], &ourview, NULL) <= 0) {
                                                fprintf(stderr,
                                        "%s: not a view file\n", argv[i]);
                                                exit(1);
                                        }
                                        continue;
                                default:        /* view option? */
                                        rval = getviewopt(&ourview, argc-i, argv+i);
                                        if (rval >= 0) {
                                                i += rval;
                                                continue;
                                        }
                                        break;
                                }
                                break;
                        case 'p':               /* pixel aspect ratio? */
                                if (argv[i][2] == 'a' && !argv[i][3])
                                        pixaspect = atof(argv[i+1]);
                                break;
                        case 'x':               /* piece x resolution */
                                if (!argv[i][2])
                                        hres = atoi(argv[i+1]);
                                break;
                        case 'y':               /* piece y resolution */
                                if (!argv[i][2])
                                        vres = atoi(argv[i+1]);
                                break;
                        case 'X':               /* horizontal multiplier */
                                if (argv[i][2])
                                        break;
                                hmult = atoi(argv[++i]);
                                continue;
                        case 'Y':               /* vertical multiplier */
                                if (argv[i][2])
                                        break;
                                vmult = atoi(argv[++i]);
                                continue;
                        case 'F':               /* syncronization file */
                                if (argv[i][2])
                                        break;
                                if ((syncfd = open(argv[++i], O_RDWR)) < 0) {
                                        fprintf(stderr, "%s: cannot open\n",
                                                        argv[i]);
                                        exit(1);
                                }
                                continue;
                        case 'o':               /* output file */
                                if (argv[i][2])
                                        break;
                                outfile = argv[++i];
                                continue;
                        }
                rpargv[rpargc++] = argv[i];
        }
        rpargv[rpargc] = NULL;
        if (outfile == NULL) {
                fprintf(stderr, "%s: missing output file\n", argv[0]);
                exit(1);
        }
        init(argc, argv);
        rpiece();
        rval = cleanup(0);
        exit(rval);
}


init(ac, av)                    /* set up output file and start rpict */
int  ac;
char  **av;
{
        extern char  VersionID[];
        char  *err;
        FILE  *fp;
        int  hr, vr;
                                        /* set up view */
        if ((err = setview(&ourview)) != NULL) {
                fprintf(stderr, "%s: %s\n", progname, err);
                exit(1);
        }
        if (syncfd != -1) {
                char  buf[32];
                buf[read(syncfd, buf, sizeof(buf)-1)] = '\0';
                sscanf(buf, "%d %d", &hmult, &vmult);
        }
        normaspect(viewaspect(&ourview)*hmult/vmult, &pixaspect, &hres, &vres);
                                        /* open output file */
        if ((outfd = open(outfile, O_WRONLY|O_CREAT|O_EXCL, 0666)) >= 0) {
                if ((fp = fdopen(dup(outfd), "w")) == NULL)
                        goto filerr;
                printargs(ac, av, fp);          /* write header */
                fprintf(fp, "SOFTWARE= %s\n", VersionID);
                fputs(VIEWSTR, fp);
                fprintview(&ourview, fp);
                putc('\n', fp);
                if (pixaspect < .99 || pixaspect > 1.01)
                        fputaspect(pixaspect, fp);
                fputformat(COLRFMT, fp);
                putc('\n', fp);
                fprtresolu(hres*hmult, vres*vmult, fp);
        } else if ((outfd = open(outfile, O_RDWR)) >= 0) {
                if ((fp = fdopen(dup(outfd), "r+")) == NULL)
                        goto filerr;
                getheader(fp, NULL, NULL);      /* skip header */
                if (fscnresolu(&hr, &vr, fp) < 0 ||     /* check resolution */
                                hr != hres*hmult || vr != vres*vmult) {
                        fprintf(stderr, "%s: resolution mismatch on file \"%s\"\n",
                                        progname, outfile);
                        exit(1);
                }
        } else {
                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]);
                exit(1);
        }
        if ((fromrp = fdopen(rpd[0], "r")) == NULL ||
                        (torp = fdopen(rpd[1], "w")) == NULL) {
                fprintf(stderr, "%s: cannot open stream to %s\n",
                                progname, rpargv[0]);
                exit(1);
        }
        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: i/o error on file \"%s\"\n", progname, outfile);
        exit(1);
}


int
nextpiece(xp, yp)               /* get next piece assignment */
int  *xp, *yp;
{
        extern char  *fgets();
        struct flock  fls;
        char  buf[64];

        if (gotalrm)                    /* someone wants us to quit */
                return(0);
        if (syncfd != -1) {             /* use sync file */
                fls.l_type = F_WRLCK;           /* gain exclusive access */
                fls.l_whence = 0;
                fls.l_start = 0L;
                fls.l_len = 0L;
                fcntl(syncfd, F_SETLKW, &fls);
                lseek(syncfd, 0L, 0);
                buf[read(syncfd, buf, sizeof(buf)-1)] = '\0';
                if (sscanf(buf, "%*d %*d %d %d", xp, yp) < 2) {
                        *xp = hmult-1;
                        *yp = vmult;
                }
                if (--(*yp) < 0) {              /* decrement position */
                        *yp = vmult-1;
                        if (--(*xp) < 0) {      /* all done! */
                                close(syncfd);
                                return(0);
                        }
                }
                sprintf(buf, "%d %d\n%d %d\n", hmult, vmult, *xp, *yp);
                lseek(syncfd, 0L, 0);           /* write new position */
                write(syncfd, buf, strlen(buf));
                fls.l_type = F_UNLCK;           /* release sync file */
                fcntl(syncfd, F_SETLKW, &fls);
                return(1);
        }
        if (fgets(buf, sizeof(buf), stdin) == NULL)     /* use stdin */
                return(0);
        if (sscanf(buf, "%d %d", xp, yp) == 2)
                return(1);
        fprintf(stderr, "%s: input format error\n", progname);
        exit(cleanup(1));
}


int
cleanup(rstat)                  /* close rpict process and clean up */
int  rstat;
{
        int  status;

        free((char *)pbuf);
        fclose(torp);
        fclose(fromrp);
        while (wait(&status) != -1)
                if (rstat == 0)
                        rstat = status>>8 & 0xff;
        return(rstat);
}


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)) {
                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);                   /* assigns piece to rpict */
                putpiece(xorg, yorg);           /* place piece in output */
                if (verbose) {                  /* notify caller */
                        printf("%d %d done\n", xorg, yorg);
                        fflush(stdout);
                }
        }
}


int
putpiece(xpos, ypos)            /* get next piece from rpict */
int  xpos, ypos;
{
        struct flock  fls;
        int  pid, status;
        int  hr, vr;
        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(cleanup(1));
        }
                                /* 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(cleanup(1));
        }
                                /* 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(cleanup(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--;
                }
                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;
                }
        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);
}
Revision:	2.13
Committed:	Thu Nov 12 10:13:35 1992 UTC (31 years, 5 months ago) by greg
Content type:	text/plain
Branch:	MAIN
Changes since 2.12:	+2 -2 lines
Log Message:	minor bug fix for compilers that don't handle variable arguments
#	User	Rev	Content
1	greg	2.1	/* Copyright (c) 1992 Regents of the University of California */
2
3			#ifndef lint
4			static char SCCSid[] = "$SunId$ LBL";
5			#endif
6
7			/*
8			* Generate sections of a picture.
9			*/
10
11			#include "standard.h"
12			#include <fcntl.h>
13	greg	2.6	#include <signal.h>
14	greg	2.1	#include "color.h"
15			#include "view.h"
16			#include "resolu.h"
17
18	greg	2.12	#ifndef NFS
19			#define NFS 1
20			#endif
21	greg	2.9	/* set the following to 0 to forgo forking */
22			#ifndef MAXFORK
23	greg	2.12	#if NFS
24	greg	2.10	#define MAXFORK 3 /* allotment of duped processes */
25	greg	2.12	#else
26			#define MAXFORK 0
27	greg	2.9	#endif
28	greg	2.12	#endif
29	greg	2.9
30	greg	2.1	/* rpict command */
31	greg	2.4	char *rpargv[128] = {"rpict", "-S", "1", "-x", "512", "-y", "512", "-pa", "1"};
32			int rpargc = 9;
33	greg	2.1	int rpd[3];
34			FILE torp, fromrp;
35	greg	2.8	COLR *pbuf;
36	greg	2.1	/* our view parameters */
37			VIEW ourview = STDVIEW;
38	greg	2.4	double pixaspect = 1.0;
39	greg	2.1	int hres = 512, vres = 512, hmult = 2, vmult = 2;
40			/* output file */
41			char *outfile = NULL;
42			int outfd;
43			long scanorig;
44	greg	2.5	int syncfd = -1; /* lock file descriptor */
45	greg	2.9	int nforked = 0;
46	greg	2.1
47			char *progname;
48			int verbose = 0;
49
50			extern long lseek(), ftell();
51
52	greg	2.6	int gotalrm = 0;
53			int onalrm() { gotalrm++; }
54	greg	2.1
55	greg	2.6
56	greg	2.1	main(argc, argv)
57			int argc;
58			char *argv[];
59			{
60			register int i, rval;
61
62			progname = argv[0];
63			for (i = 1; i < argc; i++) {
64			if (argv[i][0] == '-')
65			switch (argv[i][1]) {
66			case 'v':
67			switch (argv[i][2]) {
68			case '\0': /* verbose option */
69			verbose = !verbose;
70			continue;
71			case 'f': /* view file */
72			if (viewfile(argv[++i], &ourview, NULL) <= 0) {
73			fprintf(stderr,
74			"%s: not a view file\n", argv[i]);
75			exit(1);
76			}
77			continue;
78			default: /* view option? */
79			rval = getviewopt(&ourview, argc-i, argv+i);
80			if (rval >= 0) {
81			i += rval;
82			continue;
83			}
84			break;
85			}
86			break;
87			case 'p': /* pixel aspect ratio? */
88			if (argv[i][2] == 'a' && !argv[i][3])
89			pixaspect = atof(argv[i+1]);
90			break;
91			case 'x': /* piece x resolution */
92			if (!argv[i][2])
93			hres = atoi(argv[i+1]);
94			break;
95			case 'y': /* piece y resolution */
96			if (!argv[i][2])
97			vres = atoi(argv[i+1]);
98			break;
99			case 'X': /* horizontal multiplier */
100			if (argv[i][2])
101			break;
102			hmult = atoi(argv[++i]);
103			continue;
104			case 'Y': /* vertical multiplier */
105			if (argv[i][2])
106			break;
107			vmult = atoi(argv[++i]);
108			continue;
109	greg	2.5	case 'F': /* syncronization file */
110			if (argv[i][2])
111			break;
112			if ((syncfd = open(argv[++i], O_RDWR)) < 0) {
113			fprintf(stderr, "%s: cannot open\n",
114			argv[i]);
115			exit(1);
116			}
117			continue;
118	greg	2.1	case 'o': /* output file */
119			if (argv[i][2])
120			break;
121			outfile = argv[++i];
122			continue;
123			}
124			rpargv[rpargc++] = argv[i];
125			}
126			rpargv[rpargc] = NULL;
127			if (outfile == NULL) {
128			fprintf(stderr, "%s: missing output file\n", argv[0]);
129			exit(1);
130			}
131			init(argc, argv);
132			rpiece();
133	greg	2.10	rval = cleanup(0);
134	greg	2.1	exit(rval);
135			}
136
137
138			init(ac, av) /* set up output file and start rpict */
139			int ac;
140			char **av;
141			{
142	greg	2.2	extern char VersionID[];
143	greg	2.1	char *err;
144			FILE *fp;
145			int hr, vr;
146			/* set up view */
147			if ((err = setview(&ourview)) != NULL) {
148			fprintf(stderr, "%s: %s\n", progname, err);
149			exit(1);
150			}
151	greg	2.5	if (syncfd != -1) {
152			char buf[32];
153			buf[read(syncfd, buf, sizeof(buf)-1)] = '\0';
154			sscanf(buf, "%d %d", &hmult, &vmult);
155			}
156	greg	2.1	normaspect(viewaspect(&ourview)*hmult/vmult, &pixaspect, &hres, &vres);
157			/* open output file */
158			if ((outfd = open(outfile, O_WRONLY\|O_CREAT\|O_EXCL, 0666)) >= 0) {
159			if ((fp = fdopen(dup(outfd), "w")) == NULL)
160			goto filerr;
161			printargs(ac, av, fp); /* write header */
162	greg	2.2	fprintf(fp, "SOFTWARE= %s\n", VersionID);
163	greg	2.1	fputs(VIEWSTR, fp);
164			fprintview(&ourview, fp);
165			putc('\n', fp);
166			if (pixaspect < .99 \|\| pixaspect > 1.01)
167			fputaspect(pixaspect, fp);
168			fputformat(COLRFMT, fp);
169			putc('\n', fp);
170			fprtresolu(hreshmult, vresvmult, fp);
171			} else if ((outfd = open(outfile, O_RDWR)) >= 0) {
172			if ((fp = fdopen(dup(outfd), "r+")) == NULL)
173			goto filerr;
174	greg	2.13	getheader(fp, NULL, NULL); /* skip header */
175	greg	2.1	if (fscnresolu(&hr, &vr, fp) < 0 \|\| /* check resolution */
176			hr != hreshmult \|\| vr != vresvmult) {
177	greg	2.8	fprintf(stderr, "%s: resolution mismatch on file \"%s\"\n",
178			progname, outfile);
179	greg	2.1	exit(1);
180			}
181			} else {
182	greg	2.8	fprintf(stderr, "%s: cannot open file \"%s\"\n",
183			progname, outfile);
184	greg	2.1	exit(1);
185			}
186			scanorig = ftell(fp); /* record position of first scanline */
187			if (fclose(fp) == -1) /* done with stream i/o */
188			goto filerr;
189	greg	2.12	#if NFS
190	greg	2.8	sync(); /* flush NFS buffers */
191	greg	2.12	#endif
192	greg	2.1	/* start rpict process */
193			if (open_process(rpd, rpargv) <= 0) {
194	greg	2.3	fprintf(stderr, "%s: cannot start %s\n", progname, rpargv[0]);
195	greg	2.1	exit(1);
196			}
197			if ((fromrp = fdopen(rpd[0], "r")) == NULL \|\|
198			(torp = fdopen(rpd[1], "w")) == NULL) {
199			fprintf(stderr, "%s: cannot open stream to %s\n",
200			progname, rpargv[0]);
201			exit(1);
202			}
203	greg	2.8	if ((pbuf = (COLR )malloc(hresvres*sizeof(COLR))) == NULL) {
204	greg	2.1	fprintf(stderr, "%s: out of memory\n", progname);
205			exit(1);
206			}
207	greg	2.6	signal(SIGALRM, onalrm);
208	greg	2.1	return;
209			filerr:
210	greg	2.8	fprintf(stderr, "%s: i/o error on file \"%s\"\n", progname, outfile);
211	greg	2.1	exit(1);
212			}
213
214
215			int
216	greg	2.5	nextpiece(xp, yp) /* get next piece assignment */
217			int xp, yp;
218			{
219			extern char *fgets();
220			struct flock fls;
221			char buf[64];
222
223	greg	2.6	if (gotalrm) /* someone wants us to quit */
224			return(0);
225			if (syncfd != -1) { /* use sync file */
226	greg	2.5	fls.l_type = F_WRLCK; /* gain exclusive access */
227			fls.l_whence = 0;
228			fls.l_start = 0L;
229			fls.l_len = 0L;
230			fcntl(syncfd, F_SETLKW, &fls);
231			lseek(syncfd, 0L, 0);
232			buf[read(syncfd, buf, sizeof(buf)-1)] = '\0';
233			if (sscanf(buf, "%d %d %d %d", xp, yp) < 2) {
234	greg	2.8	*xp = hmult-1;
235			*yp = vmult;
236			}
237			if (--(yp) < 0) { / decrement position */
238	greg	2.5	*yp = vmult-1;
239	greg	2.8	if (--(xp) < 0) { / all done! */
240	greg	2.5	close(syncfd);
241			return(0);
242			}
243			}
244			sprintf(buf, "%d %d\n%d %d\n", hmult, vmult, xp, yp);
245			lseek(syncfd, 0L, 0); /* write new position */
246			write(syncfd, buf, strlen(buf));
247			fls.l_type = F_UNLCK; /* release sync file */
248			fcntl(syncfd, F_SETLKW, &fls);
249			return(1);
250			}
251	greg	2.6	if (fgets(buf, sizeof(buf), stdin) == NULL) /* use stdin */
252	greg	2.5	return(0);
253			if (sscanf(buf, "%d %d", xp, yp) == 2)
254			return(1);
255			fprintf(stderr, "%s: input format error\n", progname);
256	greg	2.10	exit(cleanup(1));
257	greg	2.5	}
258
259
260			int
261	greg	2.10	cleanup(rstat) /* close rpict process and clean up */
262			int rstat;
263	greg	2.1	{
264	greg	2.10	int status;
265	greg	2.1
266	greg	2.8	free((char *)pbuf);
267	greg	2.1	fclose(torp);
268			fclose(fromrp);
269	greg	2.10	while (wait(&status) != -1)
270	greg	2.9	if (rstat == 0)
271			rstat = status>>8 & 0xff;
272			return(rstat);
273	greg	2.1	}
274
275
276			rpiece() /* render picture piece by piece */
277			{
278			VIEW pview;
279			int xorg, yorg;
280	greg	2.11	/* compute view parameters */
281			copystruct(&pview, &ourview);
282			switch (ourview.type) {
283			case VT_PER:
284			pview.horiz = 2.180./PIatan(
285			tan(PI/180./2.*ourview.horiz)/hmult );
286			pview.vert = 2.180./PIatan(
287			tan(PI/180./2.*ourview.vert)/vmult );
288			break;
289			case VT_PAR:
290			case VT_ANG:
291			pview.horiz = ourview.horiz / hmult;
292			pview.vert = ourview.vert / vmult;
293			break;
294			case VT_HEM:
295			pview.horiz = 2.180./PIasin(
296			sin(PI/180./2.*ourview.horiz)/hmult );
297			pview.vert = 2.180./PIasin(
298			sin(PI/180./2.*ourview.vert)/vmult );
299			break;
300			default:
301			fprintf(stderr, "%s: unknown view type '-vt%c'\n",
302			progname, ourview.type);
303			exit(cleanup(1));
304			}
305			/* render each piece */
306	greg	2.5	while (nextpiece(&xorg, &yorg)) {
307	greg	2.11	pview.hoff = ourview.hoff + xorg - 0.5*(hmult-1);
308			pview.voff = ourview.voff + yorg - 0.5*(vmult-1);
309	greg	2.1	fputs(VIEWSTR, torp);
310			fprintview(&pview, torp);
311			putc('\n', torp);
312	greg	2.11	fflush(torp); /* assigns piece to rpict */
313	greg	2.1	putpiece(xorg, yorg); /* place piece in output */
314			if (verbose) { /* notify caller */
315	greg	2.5	printf("%d %d done\n", xorg, yorg);
316			fflush(stdout);
317	greg	2.1	}
318			}
319			}
320
321
322	greg	2.9	int
323	greg	2.1	putpiece(xpos, ypos) /* get next piece from rpict */
324			int xpos, ypos;
325			{
326	greg	2.7	struct flock fls;
327	greg	2.9	int pid, status;
328	greg	2.1	int hr, vr;
329	greg	2.8	register int y;
330			/* check bounds */
331	greg	2.5	if (xpos < 0 \| ypos < 0 \| xpos >= hmult \| ypos >= vmult) {
332			fprintf(stderr, "%s: requested piece (%d,%d) out of range\n",
333			progname, xpos, ypos);
334	greg	2.10	exit(cleanup(1));
335	greg	2.5	}
336	greg	2.8	/* check header from rpict */
337	greg	2.13	getheader(fromrp, NULL, NULL);
338	greg	2.11	if (fscnresolu(&hr, &vr, fromrp) < 0 \|\| hr != hres \| vr != vres) {
339	greg	2.3	fprintf(stderr, "%s: resolution mismatch from %s\n",
340			progname, rpargv[0]);
341	greg	2.10	exit(cleanup(1));
342	greg	2.1	}
343	greg	2.8	/* load new piece into buffer */
344			for (y = 0; y < vr; y++)
345			if (freadcolrs(pbuf+y*hr, hr, fromrp) < 0) {
346	greg	2.3	fprintf(stderr, "%s: read error from %s\n",
347			progname, rpargv[0]);
348	greg	2.10	exit(cleanup(1));
349	greg	2.1	}
350	greg	2.9	#if MAXFORK
351			/* fork so we don't slow rpict down */
352			if ((pid = fork()) > 0) {
353	greg	2.10	if (++nforked >= MAXFORK) {
354	greg	2.9	wait(&status); /* reap a child */
355			if (status)
356	greg	2.10	exit(cleanup(status>>8 & 0xff));
357	greg	2.9	nforked--;
358			}
359			return(pid);
360			}
361			#else
362			pid = -1; /* no forking */
363			#endif
364	greg	2.12	#if NFS
365	greg	2.8	/* lock file section so NFS doesn't mess up */
366			fls.l_whence = 0;
367			fls.l_len = (long)vreshmulthres*sizeof(COLR);
368			fls.l_start = scanorig + (vmult-1-ypos)*fls.l_len;
369			fls.l_type = F_WRLCK;
370			fcntl(outfd, F_SETLKW, &fls);
371	greg	2.12	#endif
372	greg	2.8	/* write new piece to file */
373			if (lseek(outfd, fls.l_start+(long)xposhressizeof(COLR), 0) == -1)
374			goto seekerr;
375	greg	2.9	if (hmult == 1) {
376			if (writebuf(outfd, (char *)pbuf,
377			vrhrsizeof(COLR)) != vrhrsizeof(COLR))
378			goto writerr;
379			} else
380			for (y = 0; y < vr; y++) {
381			if (writebuf(outfd, (char )(pbuf+yhr),
382			hrsizeof(COLR)) != hrsizeof(COLR))
383			goto writerr;
384			if (y < vr-1 && lseek(outfd,
385			(long)(hmult-1)hrsizeof(COLR),
386			1) == -1)
387			goto seekerr;
388	greg	2.1	}
389	greg	2.9	if (pid == -1) { /* fork failed */
390	greg	2.12	#if NFS
391	greg	2.9	fls.l_type = F_UNLCK; /* release lock */
392			fcntl(outfd, F_SETLKW, &fls);
393	greg	2.12	#endif
394	greg	2.9	return(0);
395	greg	2.1	}
396	greg	2.9	_exit(0); /* else exit child process (releasing lock) */
397	greg	2.8	seekerr:
398			fprintf(stderr, "%s: seek error on file \"%s\"\n", progname, outfile);
399	greg	2.9	_exit(1);
400			writerr:
401			fprintf(stderr, "%s: write error on file \"%s\"\n", progname, outfile);
402			_exit(1);
403	greg	2.1	}