ViewVC Help
View File | Revision Log | Show Annotations | Download File | Root Listing
root/radiance/ray/src/rt/ambient.c
Revision: 2.42
Committed: Thu Jan 2 09:37:13 1997 UTC (27 years, 4 months ago) by greg
Content type: text/plain
Branch: MAIN
Changes since 2.41: +2 -1 lines
Log Message:
corrected problem in error reporting

File Contents

# User Rev Content
1 greg 2.38 /* Copyright (c) 1996 Regents of the University of California */
2 greg 1.1
3     #ifndef lint
4     static char SCCSid[] = "$SunId$ LBL";
5     #endif
6    
7     /*
8     * ambient.c - routines dealing with ambient (inter-reflected) component.
9     */
10    
11     #include "ray.h"
12    
13     #include "octree.h"
14    
15 greg 1.8 #include "otypes.h"
16    
17 greg 1.14 #include "ambient.h"
18    
19 greg 1.1 #include "random.h"
20    
21 greg 2.32 #ifndef OCTSCALE
22 greg 2.29 #define OCTSCALE 1.0 /* ceil((valid rad.)/(cube size)) */
23 greg 2.32 #endif
24 greg 1.1
25 greg 1.14 typedef struct ambtree {
26 greg 2.12 AMBVAL *alist; /* ambient value list */
27     struct ambtree *kid; /* 8 child nodes */
28 greg 1.14 } AMBTREE; /* ambient octree */
29    
30 greg 1.1 extern CUBE thescene; /* contains space boundaries */
31    
32 greg 2.27 extern char *shm_boundary; /* memory sharing boundary */
33 greg 2.26
34 greg 2.12 #define MAXASET 511 /* maximum number of elements in ambient set */
35     OBJECT ambset[MAXASET+1]={0}; /* ambient include/exclude set */
36 greg 1.1
37 greg 2.12 double maxarad; /* maximum ambient radius */
38     double minarad; /* minimum ambient radius */
39 greg 1.1
40 greg 2.12 static AMBTREE atrunk; /* our ambient trunk node */
41 greg 1.1
42     static FILE *ambfp = NULL; /* ambient file pointer */
43 greg 2.16 static int nunflshed = 0; /* number of unflushed ambient values */
44 greg 1.1
45 greg 2.26 #ifndef SORT_THRESH
46     #ifdef BIGMEM
47 greg 2.27 #define SORT_THRESH ((9L<<20)/sizeof(AMBVAL))
48 greg 2.26 #else
49 greg 2.27 #define SORT_THRESH ((3L<<20)/sizeof(AMBVAL))
50 greg 2.26 #endif
51     #endif
52     #ifndef SORT_INTVL
53 greg 2.41 #define SORT_INTVL (SORT_THRESH<<1)
54 greg 2.26 #endif
55 greg 2.28 #ifndef MAX_SORT_INTVL
56 greg 2.41 #define MAX_SORT_INTVL (SORT_INTVL<<6)
57 greg 2.28 #endif
58 greg 2.26
59 greg 2.32 static COLOR avsum = BLKCOLOR; /* computed ambient value sum */
60 greg 2.35 static unsigned int nambvals = 0; /* total number of indirect values */
61     static unsigned int nambshare = 0; /* number of values from file */
62 greg 2.27 static unsigned long ambclock = 0; /* ambient access clock */
63     static unsigned long lastsort = 0; /* time of last value sort */
64 greg 2.26 static long sortintvl = SORT_INTVL; /* time until next sort */
65    
66     #define MAXACLOCK (1L<<30) /* clock turnover value */
67 greg 2.27 /*
68     * Track access times unless we are sharing ambient values
69     * through memory on a multiprocessor, when we want to avoid
70 greg 2.35 * claiming our own memory (copy on write). Go ahead anyway
71     * if more than two thirds of our values are unshared.
72 greg 2.27 */
73 greg 2.35 #define tracktime (shm_boundary == NULL || nambvals > 3*nambshare)
74 greg 2.26
75 greg 2.12 #define AMBFLUSH (BUFSIZ/AMBVALSIZ)
76 greg 2.6
77 greg 2.12 #define newambval() (AMBVAL *)bmalloc(sizeof(AMBVAL))
78 greg 1.1
79 greg 2.7 extern long ftell(), lseek();
80 greg 2.40 static int initambfile(), avsave(), avinsert(), sortambvals(), avlmemi();
81 greg 2.20 static AMBVAL *avstore();
82 greg 2.19 #ifdef F_SETLKW
83     static aflock();
84     #endif
85 greg 1.1
86 greg 2.7
87 greg 2.3 setambres(ar) /* set ambient resolution */
88     int ar;
89     {
90 greg 2.21 ambres = ar < 0 ? 0 : ar; /* may be done already */
91 greg 2.3 /* set min & max radii */
92     if (ar <= 0) {
93 greg 2.25 minarad = 0;
94 greg 2.3 maxarad = thescene.cusize / 2.0;
95     } else {
96     minarad = thescene.cusize / ar;
97 greg 2.30 maxarad = 64 * minarad; /* heuristic */
98 greg 2.3 if (maxarad > thescene.cusize / 2.0)
99     maxarad = thescene.cusize / 2.0;
100     }
101 greg 2.25 if (minarad <= FTINY)
102     minarad = 10*FTINY;
103     if (maxarad <= minarad)
104     maxarad = 64 * minarad;
105 greg 2.3 }
106    
107    
108 greg 2.21 setambacc(newa) /* set ambient accuracy */
109 greg 2.20 double newa;
110     {
111 greg 2.33 double ambdiff;
112 greg 2.20
113 greg 2.33 if (newa < 0.0)
114     newa = 0.0;
115     ambdiff = fabs(newa - ambacc);
116     if (ambdiff >= .01 && (ambacc = newa) > FTINY && nambvals > 0)
117     sortambvals(1); /* rebuild tree */
118 greg 2.20 }
119    
120    
121 greg 1.1 setambient(afile) /* initialize calculation */
122     char *afile;
123     {
124 greg 2.37 long pos, flen;
125 greg 2.12 AMBVAL amb;
126 greg 2.3 /* init ambient limits */
127     setambres(ambres);
128 greg 2.21 setambacc(ambacc);
129 greg 2.19 if (afile == NULL)
130     return;
131 greg 2.20 if (ambacc <= FTINY) {
132 greg 2.21 sprintf(errmsg, "zero ambient accuracy so \"%s\" not opened",
133 greg 2.20 afile);
134     error(WARNING, errmsg);
135     return;
136     }
137 greg 2.3 /* open ambient file */
138 greg 2.19 if ((ambfp = fopen(afile, "r+")) != NULL) {
139     initambfile(0);
140 greg 2.37 pos = ftell(ambfp);
141 greg 2.19 while (readambval(&amb, ambfp))
142 greg 2.21 avinsert(avstore(&amb));
143 greg 2.19 /* align */
144 greg 2.37 pos += (long)nambvals*AMBVALSIZ;
145     flen = lseek(fileno(ambfp), 0L, 2);
146     if (flen != pos) {
147 greg 2.42 sprintf(errmsg,
148 greg 2.37 "ignoring last %ld values in ambient file (corrupted)",
149     (flen - pos)/AMBVALSIZ);
150 greg 2.42 error(WARNING, errmsg);
151 greg 2.37 fseek(ambfp, pos, 0);
152     ftruncate(fileno(ambfp), pos);
153     }
154 greg 2.35 nambshare = nambvals;
155 greg 2.19 } else if ((ambfp = fopen(afile, "w+")) != NULL)
156     initambfile(1);
157     else {
158     sprintf(errmsg, "cannot open ambient file \"%s\"", afile);
159     error(SYSTEM, errmsg);
160 greg 2.16 }
161 greg 2.19 nunflshed++; /* lie */
162     ambsync();
163 greg 1.8 }
164    
165    
166     ambnotify(obj) /* record new modifier */
167 greg 2.12 OBJECT obj;
168 greg 1.8 {
169 greg 1.11 static int hitlimit = 0;
170 greg 2.12 register OBJREC *o = objptr(obj);
171 greg 1.8 register char **amblp;
172    
173 greg 1.11 if (hitlimit || !ismodifier(o->otype))
174 greg 1.8 return;
175     for (amblp = amblist; *amblp != NULL; amblp++)
176     if (!strcmp(o->oname, *amblp)) {
177 greg 1.11 if (ambset[0] >= MAXASET) {
178     error(WARNING, "too many modifiers in ambient list");
179     hitlimit++;
180     return; /* should this be fatal? */
181     }
182 greg 1.8 insertelem(ambset, obj);
183     return;
184 greg 1.1 }
185     }
186    
187    
188 greg 2.34 ambient(acol, r, nrm) /* compute ambient component for ray */
189 greg 1.1 COLOR acol;
190     register RAY *r;
191 greg 2.34 FVECT nrm;
192 greg 1.1 {
193     static int rdepth = 0; /* ambient recursion */
194 greg 2.12 double d;
195 greg 1.1
196     if (ambdiv <= 0) /* no ambient calculation */
197     goto dumbamb;
198     /* check number of bounces */
199 greg 1.16 if (rdepth >= ambounce)
200 greg 1.1 goto dumbamb;
201     /* check ambient list */
202     if (ambincl != -1 && r->ro != NULL &&
203     ambincl != inset(ambset, r->ro->omod))
204     goto dumbamb;
205    
206     if (ambacc <= FTINY) { /* no ambient storage */
207 greg 1.16 rdepth++;
208     d = doambient(acol, r, r->rweight, NULL, NULL);
209     rdepth--;
210 greg 2.32 if (d <= FTINY)
211 greg 1.1 goto dumbamb;
212 greg 1.16 return;
213 greg 1.1 }
214 greg 2.40
215     if (tracktime) /* sort to minimize thrashing */
216     sortambvals(0);
217 greg 1.1 /* get ambient value */
218     setcolor(acol, 0.0, 0.0, 0.0);
219 greg 2.34 d = sumambient(acol, r, nrm, rdepth,
220 greg 1.16 &atrunk, thescene.cuorg, thescene.cusize);
221 greg 2.32 if (d > FTINY) {
222 greg 1.16 scalecolor(acol, 1.0/d);
223 greg 2.32 return;
224 greg 1.16 }
225 greg 2.33 rdepth++; /* need to cache new value */
226 greg 2.34 d = makeambient(acol, r, nrm, rdepth-1);
227 greg 2.32 rdepth--;
228 greg 1.16 if (d > FTINY)
229     return;
230 greg 1.1 dumbamb: /* return global value */
231     copycolor(acol, ambval);
232 greg 2.36 if (ambvwt <= 0 | nambvals == 0)
233 greg 2.32 return;
234 greg 2.36 scalecolor(acol, (double)ambvwt);
235 greg 2.32 addcolor(acol, avsum); /* average in computations */
236 greg 2.36 d = 1.0/(ambvwt+nambvals);
237 greg 2.32 scalecolor(acol, d);
238 greg 1.1 }
239    
240    
241     double
242 greg 2.34 sumambient(acol, r, rn, al, at, c0, s) /* get interpolated ambient value */
243 greg 1.1 COLOR acol;
244     register RAY *r;
245 greg 2.34 FVECT rn;
246 greg 1.16 int al;
247 greg 2.12 AMBTREE *at;
248 greg 1.1 FVECT c0;
249 greg 2.12 double s;
250 greg 1.1 {
251 greg 2.12 double d, e1, e2, wt, wsum;
252 greg 1.1 COLOR ct;
253     FVECT ck0;
254     int i;
255     register int j;
256 greg 2.12 register AMBVAL *av;
257 greg 2.29
258     wsum = 0.0;
259 greg 1.7 /* do this node */
260 greg 1.1 for (av = at->alist; av != NULL; av = av->next) {
261 greg 2.26 if (tracktime)
262 greg 2.40 av->latick = ambclock;
263 greg 1.1 /*
264 greg 1.16 * Ambient level test.
265 greg 1.1 */
266 greg 2.23 if (av->lvl > al) /* list sorted, so this works */
267     break;
268     if (av->weight < r->rweight-FTINY)
269 greg 1.1 continue;
270     /*
271     * Ambient radius test.
272     */
273 greg 2.29 d = av->pos[0] - r->rop[0];
274     e1 = d * d;
275     d = av->pos[1] - r->rop[1];
276     e1 += d * d;
277     d = av->pos[2] - r->rop[2];
278     e1 += d * d;
279 greg 1.1 e1 /= av->rad * av->rad;
280     if (e1 > ambacc*ambacc*1.21)
281     continue;
282     /*
283     * Normal direction test.
284     */
285     e2 = (1.0 - DOT(av->dir, r->ron)) * r->rweight;
286     if (e2 < 0.0) e2 = 0.0;
287     if (e1 + e2 > ambacc*ambacc*1.21)
288     continue;
289     /*
290     * Ray behind test.
291     */
292     d = 0.0;
293     for (j = 0; j < 3; j++)
294     d += (r->rop[j] - av->pos[j]) *
295     (av->dir[j] + r->ron[j]);
296 greg 1.18 if (d*0.5 < -minarad*ambacc-.001)
297 greg 1.1 continue;
298     /*
299     * Jittering final test reduces image artifacts.
300     */
301     wt = sqrt(e1) + sqrt(e2);
302 greg 2.31 if (wt > ambacc*(.9+.2*urand(9015+samplendx)))
303 greg 1.1 continue;
304     if (wt <= 1e-3)
305     wt = 1e3;
306     else
307     wt = 1.0 / wt;
308     wsum += wt;
309 greg 2.34 extambient(ct, av, r->rop, rn);
310 greg 1.1 scalecolor(ct, wt);
311     addcolor(acol, ct);
312 greg 1.7 }
313     if (at->kid == NULL)
314     return(wsum);
315     /* do children */
316     s *= 0.5;
317     for (i = 0; i < 8; i++) {
318     for (j = 0; j < 3; j++) {
319     ck0[j] = c0[j];
320     if (1<<j & i)
321     ck0[j] += s;
322     if (r->rop[j] < ck0[j] - OCTSCALE*s)
323     break;
324     if (r->rop[j] > ck0[j] + (1.0+OCTSCALE)*s)
325     break;
326     }
327     if (j == 3)
328 greg 2.34 wsum += sumambient(acol, r, rn, al, at->kid+i, ck0, s);
329 greg 1.1 }
330     return(wsum);
331     }
332    
333    
334     double
335 greg 2.34 makeambient(acol, r, rn, al) /* make a new ambient value */
336 greg 1.1 COLOR acol;
337     register RAY *r;
338 greg 2.34 FVECT rn;
339 greg 1.16 int al;
340 greg 1.1 {
341 greg 2.12 AMBVAL amb;
342 greg 1.14 FVECT gp, gd;
343 greg 1.16 /* compute weight */
344     amb.weight = pow(AVGREFL, (double)al);
345 greg 2.33 if (r->rweight < 0.1*amb.weight) /* heuristic */
346 greg 1.16 amb.weight = r->rweight;
347     /* compute ambient */
348     amb.rad = doambient(acol, r, amb.weight, gp, gd);
349 greg 2.33 if (amb.rad <= FTINY)
350 greg 1.1 return(0.0);
351     /* store it */
352     VCOPY(amb.pos, r->rop);
353     VCOPY(amb.dir, r->ron);
354 greg 1.16 amb.lvl = al;
355 greg 1.1 copycolor(amb.val, acol);
356 greg 1.14 VCOPY(amb.gpos, gp);
357     VCOPY(amb.gdir, gd);
358 greg 1.1 /* insert into tree */
359 greg 2.7 avsave(&amb); /* and save to file */
360 greg 2.34 if (rn != r->ron)
361     extambient(acol, &amb, r->rop, rn); /* texture */
362 greg 1.1 return(amb.rad);
363 greg 1.15 }
364    
365    
366     extambient(cr, ap, pv, nv) /* extrapolate value at pv, nv */
367     COLOR cr;
368 greg 2.12 register AMBVAL *ap;
369 greg 1.15 FVECT pv, nv;
370     {
371     FVECT v1, v2;
372     register int i;
373 greg 2.12 double d;
374 greg 1.15
375     d = 1.0; /* zeroeth order */
376     /* gradient due to translation */
377     for (i = 0; i < 3; i++)
378     d += ap->gpos[i]*(pv[i]-ap->pos[i]);
379     /* gradient due to rotation */
380     VCOPY(v1, ap->dir);
381     fcross(v2, v1, nv);
382     d += DOT(ap->gdir, v2);
383     if (d <= 0.0) {
384     setcolor(cr, 0.0, 0.0, 0.0);
385     return;
386     }
387     copycolor(cr, ap->val);
388     scalecolor(cr, d);
389 greg 1.1 }
390    
391    
392     static
393 greg 2.9 initambfile(creat) /* initialize ambient file */
394     int creat;
395     {
396     extern char *progname, *octname, VersionID[];
397    
398 greg 2.19 #ifdef F_SETLKW
399     aflock(creat ? F_WRLCK : F_RDLCK);
400     #endif
401 greg 2.12 #ifdef MSDOS
402     setmode(fileno(ambfp), O_BINARY);
403     #endif
404 greg 2.21 setbuf(ambfp, bmalloc(BUFSIZ+8));
405 greg 2.9 if (creat) { /* new file */
406 greg 2.24 newheader("RADIANCE", ambfp);
407 greg 2.41 fprintf(ambfp, "%s -av %g %g %g -aw %d -ab %d -aa %g ",
408 greg 2.9 progname, colval(ambval,RED),
409     colval(ambval,GRN), colval(ambval,BLU),
410 greg 2.41 ambvwt, ambounce, ambacc);
411 greg 2.9 fprintf(ambfp, "-ad %d -as %d -ar %d %s\n",
412     ambdiv, ambssamp, ambres,
413     octname==NULL ? "" : octname);
414     fprintf(ambfp, "SOFTWARE= %s\n", VersionID);
415     fputformat(AMBFMT, ambfp);
416     putc('\n', ambfp);
417     putambmagic(ambfp);
418 greg 2.17 } else if (checkheader(ambfp, AMBFMT, NULL) < 0 || !hasambmagic(ambfp))
419     error(USER, "bad ambient file");
420 greg 2.9 }
421    
422    
423     static
424 greg 2.7 avsave(av) /* insert and save an ambient value */
425 greg 2.12 AMBVAL *av;
426 greg 1.1 {
427 greg 2.21 avinsert(avstore(av));
428 greg 1.1 if (ambfp == NULL)
429     return;
430 greg 2.5 if (writambval(av, ambfp) < 0)
431 greg 1.1 goto writerr;
432 greg 2.16 if (++nunflshed >= AMBFLUSH)
433 greg 2.7 if (ambsync() == EOF)
434 greg 1.1 goto writerr;
435     return;
436     writerr:
437 greg 2.17 error(SYSTEM, "error writing ambient file");
438 greg 1.1 }
439    
440    
441 greg 2.20 static AMBVAL *
442     avstore(aval) /* allocate memory and store aval */
443     register AMBVAL *aval;
444     {
445     register AMBVAL *av;
446    
447     if ((av = newambval()) == NULL)
448     error(SYSTEM, "out of memory in avstore");
449     copystruct(av, aval);
450 greg 2.26 av->latick = ambclock;
451     av->next = NULL;
452 greg 2.32 addcolor(avsum, av->val); /* add to sum for averaging */
453 greg 2.26 nambvals++;
454 greg 2.20 return(av);
455     }
456    
457    
458 greg 2.26 #define ATALLOCSZ 512 /* #/8 trees to allocate at once */
459    
460     static AMBTREE *atfreelist = NULL; /* free ambient tree structures */
461    
462    
463 greg 1.1 static
464 greg 2.26 AMBTREE *
465     newambtree() /* allocate 8 ambient tree structs */
466     {
467     register AMBTREE *atp, *upperlim;
468    
469     if (atfreelist == NULL) { /* get more nodes */
470     atfreelist = (AMBTREE *)bmalloc(ATALLOCSZ*8*sizeof(AMBTREE));
471     if (atfreelist == NULL)
472     return(NULL);
473     /* link new free list */
474     upperlim = atfreelist + 8*(ATALLOCSZ-1);
475     for (atp = atfreelist; atp < upperlim; atp += 8)
476     atp->kid = atp + 8;
477     atp->kid = NULL;
478     }
479     atp = atfreelist;
480     atfreelist = atp->kid;
481     bzero((char *)atp, 8*sizeof(AMBTREE));
482     return(atp);
483     }
484    
485    
486     static
487     freeambtree(atp) /* free 8 ambient tree structs */
488     AMBTREE *atp;
489     {
490     atp->kid = atfreelist;
491     atfreelist = atp;
492     }
493    
494    
495     static
496 greg 2.21 avinsert(av) /* insert ambient value in our tree */
497 greg 2.20 register AMBVAL *av;
498 greg 1.1 {
499 greg 2.21 register AMBTREE *at;
500 greg 2.23 register AMBVAL *ap;
501     AMBVAL avh;
502 greg 1.1 FVECT ck0;
503 greg 2.21 double s;
504 greg 1.1 int branch;
505     register int i;
506    
507 greg 2.20 if (av->rad <= FTINY)
508     error(CONSISTENCY, "zero ambient radius in avinsert");
509 greg 2.21 at = &atrunk;
510     VCOPY(ck0, thescene.cuorg);
511     s = thescene.cusize;
512 greg 1.1 while (s*(OCTSCALE/2) > av->rad*ambacc) {
513     if (at->kid == NULL)
514     if ((at->kid = newambtree()) == NULL)
515 greg 2.20 error(SYSTEM, "out of memory in avinsert");
516 greg 1.1 s *= 0.5;
517     branch = 0;
518     for (i = 0; i < 3; i++)
519     if (av->pos[i] > ck0[i] + s) {
520     ck0[i] += s;
521     branch |= 1 << i;
522     }
523     at = at->kid + branch;
524     }
525 greg 2.23 avh.next = at->alist; /* order by increasing level */
526     for (ap = &avh; ap->next != NULL; ap = ap->next)
527     if (ap->next->lvl >= av->lvl)
528     break;
529     av->next = ap->next;
530     ap->next = av;
531     at->alist = avh.next;
532 greg 2.7 }
533    
534    
535 greg 2.20 static
536 greg 2.26 unloadatree(at, f) /* unload an ambient value tree */
537 greg 2.20 register AMBTREE *at;
538 greg 2.26 int (*f)();
539 greg 2.20 {
540     register AMBVAL *av;
541     register int i;
542     /* transfer values at this node */
543     for (av = at->alist; av != NULL; av = at->alist) {
544     at->alist = av->next;
545 greg 2.26 (*f)(av);
546 greg 2.20 }
547 greg 2.21 if (at->kid == NULL)
548     return;
549 greg 2.20 for (i = 0; i < 8; i++) /* transfer and free children */
550 greg 2.26 unloadatree(at->kid+i, f);
551 greg 2.20 freeambtree(at->kid);
552 greg 2.26 at->kid = NULL;
553     }
554    
555    
556 greg 2.39 static struct avl {
557     AMBVAL *p;
558     unsigned long t;
559     } *avlist1; /* ambient value list with ticks */
560     static AMBVAL **avlist2; /* memory positions for sorting */
561 greg 2.26 static int i_avlist; /* index for lists */
562    
563    
564     static
565     av2list(av)
566 greg 2.39 register AMBVAL *av;
567 greg 2.26 {
568 greg 2.27 #ifdef DEBUG
569 greg 2.26 if (i_avlist >= nambvals)
570     error(CONSISTENCY, "too many ambient values in av2list1");
571 greg 2.27 #endif
572 greg 2.39 avlist1[i_avlist].p = avlist2[i_avlist] = av;
573     avlist1[i_avlist++].t = av->latick;
574 greg 2.26 }
575    
576    
577     static int
578 greg 2.39 alatcmp(av1, av2) /* compare ambient values for MRA */
579     struct avl *av1, *av2;
580 greg 2.26 {
581 greg 2.39 register long lc = av2->t - av1->t;
582 greg 2.38 return(lc<0 ? -1 : lc>0 ? 1 : 0);
583 greg 2.26 }
584    
585    
586     static int
587     aposcmp(avp1, avp2) /* compare ambient value positions */
588     AMBVAL **avp1, **avp2;
589     {
590     return(*avp1 - *avp2);
591     }
592    
593    
594 greg 2.39 #if 1
595 greg 2.27 static int
596     avlmemi(avaddr) /* find list position from address */
597     AMBVAL *avaddr;
598     {
599     register AMBVAL **avlpp;
600    
601     avlpp = (AMBVAL **)bsearch((char *)&avaddr, (char *)avlist2,
602     nambvals, sizeof(AMBVAL *), aposcmp);
603     if (avlpp == NULL)
604     error(CONSISTENCY, "address not found in avlmemi");
605     return(avlpp - avlist2);
606     }
607     #else
608     #define avlmemi(avaddr) ((AMBVAL **)bsearch((char *)&avaddr,(char *)avlist2, \
609     nambvals,sizeof(AMBVAL *),aposcmp) - avlist2)
610     #endif
611    
612    
613 greg 2.26 static
614     sortambvals(always) /* resort ambient values */
615     int always;
616     {
617     AMBTREE oldatrunk;
618     AMBVAL tav, *tap, *pnext;
619     register int i, j;
620 greg 2.28 /* see if it's time yet */
621 greg 2.40 if (!always && (ambclock++ < lastsort+sortintvl ||
622 greg 2.28 nambvals < SORT_THRESH))
623     return;
624 greg 2.26 /*
625     * The idea here is to minimize memory thrashing
626     * in VM systems by improving reference locality.
627     * We do this by periodically sorting our stored ambient
628     * values in memory in order of most recently to least
629     * recently accessed. This ordering was chosen so that new
630     * ambient values (which tend to be less important) go into
631     * higher memory with the infrequently accessed values.
632     * Since we expect our values to need sorting less
633     * frequently as the process continues, we double our
634     * waiting interval after each call.
635     * This routine is also called by setambacc() with
636     * the "always" parameter set to 1 so that the ambient
637     * tree will be rebuilt with the new accuracy parameter.
638     */
639 greg 2.27 if (tracktime) { /* allocate pointer arrays to sort */
640 greg 2.26 avlist2 = (AMBVAL **)malloc(nambvals*sizeof(AMBVAL *));
641 greg 2.39 avlist1 = (struct avl *)malloc(nambvals*sizeof(struct avl));
642     } else {
643     avlist2 = NULL;
644     avlist1 = NULL;
645     }
646     if (avlist1 == NULL) { /* no time tracking -- rebuild tree? */
647     if (avlist2 != NULL)
648     free((char *)avlist2);
649 greg 2.27 if (always) { /* rebuild without sorting */
650     copystruct(&oldatrunk, &atrunk);
651     atrunk.alist = NULL;
652     atrunk.kid = NULL;
653     unloadatree(&oldatrunk, avinsert);
654     }
655 greg 2.26 } else { /* sort memory by last access time */
656     /*
657     * Sorting memory is tricky because it isn't contiguous.
658     * We have to sort an array of pointers by MRA and also
659     * by memory position. We then copy values in "loops"
660     * to minimize memory hits. Nevertheless, we will visit
661 greg 2.27 * everyone at least twice, and this is an expensive process
662 greg 2.26 * when we're thrashing, which is when we need to do it.
663     */
664 greg 2.27 #ifdef DEBUG
665 greg 2.29 sprintf(errmsg, "sorting %u ambient values at ambclock=%lu...",
666     nambvals, ambclock);
667 greg 2.27 eputs(errmsg);
668     #endif
669     i_avlist = 0;
670     unloadatree(&atrunk, av2list); /* empty current tree */
671     #ifdef DEBUG
672     if (i_avlist < nambvals)
673     error(CONSISTENCY, "missing ambient values in sortambvals");
674     #endif
675 greg 2.39 qsort((char *)avlist1, nambvals, sizeof(struct avl), alatcmp);
676 greg 2.26 qsort((char *)avlist2, nambvals, sizeof(AMBVAL *), aposcmp);
677     for (i = 0; i < nambvals; i++) {
678 greg 2.39 if (avlist1[i].p == NULL)
679 greg 2.26 continue;
680     tap = avlist2[i];
681     copystruct(&tav, tap);
682 greg 2.39 for (j = i; (pnext = avlist1[j].p) != tap;
683 greg 2.27 j = avlmemi(pnext)) {
684 greg 2.26 copystruct(avlist2[j], pnext);
685     avinsert(avlist2[j]);
686 greg 2.39 avlist1[j].p = NULL;
687 greg 2.26 }
688     copystruct(avlist2[j], &tav);
689     avinsert(avlist2[j]);
690 greg 2.39 avlist1[j].p = NULL;
691 greg 2.26 }
692     free((char *)avlist1);
693     free((char *)avlist2);
694 greg 2.28 /* compute new sort interval */
695     sortintvl = ambclock - lastsort;
696 greg 2.32 if (sortintvl >= MAX_SORT_INTVL/2)
697 greg 2.28 sortintvl = MAX_SORT_INTVL;
698     else
699 greg 2.26 sortintvl <<= 1; /* wait twice as long next */
700 greg 2.27 #ifdef DEBUG
701     eputs("done\n");
702     #endif
703 greg 2.26 }
704     if (ambclock >= MAXACLOCK)
705     ambclock = MAXACLOCK/2;
706     lastsort = ambclock;
707 greg 2.20 }
708    
709    
710 greg 2.18 #ifdef F_SETLKW
711 greg 2.10
712 greg 2.19 static
713     aflock(typ) /* lock/unlock ambient file */
714     int typ;
715     {
716     static struct flock fls; /* static so initialized to zeroes */
717    
718     fls.l_type = typ;
719     if (fcntl(fileno(ambfp), F_SETLKW, &fls) < 0)
720     error(SYSTEM, "cannot (un)lock ambient file");
721     }
722    
723    
724 greg 2.16 int
725 greg 2.7 ambsync() /* synchronize ambient file */
726     {
727     static FILE *ambinp = NULL;
728 greg 2.15 static long lastpos = -1;
729     long flen;
730 greg 2.12 AMBVAL avs;
731 greg 2.7 register int n;
732 greg 2.16
733     if (nunflshed == 0)
734     return(0);
735 greg 2.19 if (lastpos < 0) /* initializing (locked in initambfile) */
736     goto syncend;
737 greg 2.7 /* gain exclusive access */
738 greg 2.19 aflock(F_WRLCK);
739 greg 2.7 /* see if file has grown */
740 greg 2.15 if ((flen = lseek(fileno(ambfp), 0L, 2)) < 0)
741 greg 2.21 goto seekerr;
742 greg 2.15 if (n = flen - lastpos) { /* file has grown */
743 greg 2.17 if (ambinp == NULL) { /* use duplicate filedes */
744     ambinp = fdopen(dup(fileno(ambfp)), "r");
745 greg 2.14 if (ambinp == NULL)
746 greg 2.17 error(SYSTEM, "fdopen failed in ambsync");
747 greg 2.14 }
748 greg 2.15 if (fseek(ambinp, lastpos, 0) < 0)
749 greg 2.21 goto seekerr;
750 greg 2.15 while (n >= AMBVALSIZ) { /* load contributed values */
751 greg 2.37 if (!readambval(&avs, ambinp)) {
752     sprintf(errmsg,
753     "ambient file corrupted near character %ld",
754     flen - n);
755     error(WARNING, errmsg);
756     break;
757     }
758 greg 2.21 avinsert(avstore(&avs));
759 greg 2.15 n -= AMBVALSIZ;
760     }
761 greg 2.22 /*** seek always as safety measure
762     if (n) ***/ /* alignment */
763 greg 2.21 if (lseek(fileno(ambfp), flen-n, 0) < 0)
764     goto seekerr;
765 greg 2.7 }
766 greg 2.21 #ifdef DEBUG
767     if (ambfp->_ptr - ambfp->_base != nunflshed*AMBVALSIZ) {
768     sprintf(errmsg, "ambient file buffer at %d rather than %d",
769     ambfp->_ptr - ambfp->_base,
770     nunflshed*AMBVALSIZ);
771     error(CONSISTENCY, errmsg);
772     }
773     #endif
774 greg 2.15 syncend:
775 greg 2.7 n = fflush(ambfp); /* calls write() at last */
776 greg 2.21 if ((lastpos = lseek(fileno(ambfp), 0L, 1)) < 0)
777     goto seekerr;
778 greg 2.19 aflock(F_UNLCK); /* release file */
779 greg 2.16 nunflshed = 0;
780 greg 2.7 return(n);
781 greg 2.21 seekerr:
782     error(SYSTEM, "seek failed in ambsync");
783 greg 2.18 }
784    
785     #else
786    
787     int
788     ambsync() /* flush ambient file */
789     {
790     if (nunflshed == 0)
791     return(0);
792     nunflshed = 0;
793     return(fflush(ambfp));
794 greg 1.1 }
795 greg 2.10
796     #endif