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root/radiance/ray/src/hd/holofile.c
Revision: 3.30
Committed: Thu Dec 10 10:45:02 1998 UTC (25 years, 4 months ago) by gwlarson
Content type: text/plain
Branch: MAIN
Changes since 3.29: +1 -1 lines
Log Message:
reduced size of fragment list to speed hdflush() calls

File Contents

# Content
1 /* Copyright (c) 1998 Silicon Graphics, Inc. */
2
3 #ifndef lint
4 static char SCCSid[] = "$SunId$ SGI";
5 #endif
6
7 /*
8 * Routines for managing holodeck files
9 *
10 * 9/30/97 GWLarson
11 */
12
13 #include "holo.h"
14
15 #ifndef CACHESIZE
16 #define CACHESIZE 16 /* default cache size (Mbytes, 0==inf) */
17 #endif
18 #ifndef FREEBEAMS
19 #define FREEBEAMS 1500 /* maximum beams to free at a time */
20 #endif
21 #ifndef PCTFREE
22 #define PCTFREE 15 /* maximum fraction to free (%) */
23 #endif
24 #ifndef MAXFRAG
25 #define MAXFRAG 8191 /* maximum fragments/file to track (0==inf) */
26 #endif
27 #ifndef MINDIRSEL
28 /* minimum directory seek length */
29 #define MINDIRSEL (4*BUFSIZ/sizeof(BEAMI))
30 #endif
31
32 #ifndef BSD
33 #define write writebuf /* safe i/o routines */
34 #define read readbuf
35 #endif
36
37 #define FRAGBLK 256 /* number of fragments to allocate at a time */
38
39 unsigned hdcachesize = CACHESIZE*1024*1024; /* target cache size */
40 unsigned long hdclock; /* clock value */
41
42 HOLO *hdlist[HDMAX+1]; /* holodeck pointers (NULL term.) */
43
44 static struct fraglist {
45 short nlinks; /* number of holodeck sections using us */
46 short writerr; /* write error encountered */
47 int nfrags; /* number of known fragments */
48 BEAMI *fi; /* fragments, descending file position */
49 long flen; /* last known file length */
50 } *hdfragl; /* fragment lists, indexed by file descriptor */
51
52 static int nhdfragls; /* size of hdfragl array */
53
54
55 char *
56 hdrealloc(ptr, siz, rout) /* (re)allocate memory, retry then error */
57 char *ptr;
58 unsigned siz;
59 char *rout;
60 {
61 register char *newp;
62 /* call malloc/realloc */
63 if (ptr == NULL) newp = (char *)malloc(siz);
64 else newp = (char *)realloc(ptr, siz);
65 /* check success */
66 if (newp == NULL && rout != NULL) {
67 hdfreecache(25, NULL); /* free some memory */
68 errno = 0; /* retry */
69 newp = hdrealloc(ptr, siz, NULL);
70 if (newp == NULL) { /* give up and report error */
71 sprintf(errmsg, "out of memory in %s", rout);
72 error(SYSTEM, errmsg);
73 }
74 }
75 return(newp);
76 }
77
78
79 hdattach(fd) /* start tracking file fragments for some section */
80 register int fd;
81 {
82 if (fd >= nhdfragls) {
83 hdfragl = (struct fraglist *)hdrealloc((char *)hdfragl,
84 (fd+1)*sizeof(struct fraglist), "hdattach");
85 bzero((char *)(hdfragl+nhdfragls),
86 (fd+1-nhdfragls)*sizeof(struct fraglist));
87 nhdfragls = fd+1;
88 }
89 hdfragl[fd].nlinks++;
90 hdfragl[fd].flen = lseek(fd, 0L, 2); /* get file length */
91 }
92
93
94 /* Do we need a routine to locate file fragments given known occupants? */
95
96
97 hdrelease(fd) /* stop tracking file fragments for some section */
98 register int fd;
99 {
100 if (fd < 0 | fd >= nhdfragls || !hdfragl[fd].nlinks)
101 return;
102 if (!--hdfragl[fd].nlinks && hdfragl[fd].nfrags) {
103 free((char *)hdfragl[fd].fi);
104 hdfragl[fd].fi = NULL;
105 hdfragl[fd].nfrags = 0;
106 }
107 }
108
109
110 HOLO *
111 hdinit(fd, hproto) /* initialize a holodeck section in a file */
112 int fd; /* corresponding file descriptor */
113 HDGRID *hproto; /* holodeck section grid */
114 {
115 long rtrunc;
116 long fpos;
117 register HOLO *hp;
118 register int n;
119 /* prepare for system errors */
120 errno = 0;
121 if ((fpos = lseek(fd, 0L, 1)) < 0)
122 error(SYSTEM, "cannot determine holodeck file position");
123 if (hproto == NULL) { /* assume we're loading it */
124 HDGRID hpr;
125 /* load header */
126 if (read(fd, (char *)&hpr, sizeof(HDGRID)) != sizeof(HDGRID))
127 error(SYSTEM, "cannot load holodeck header");
128 /* allocate grid */
129 if ((hp = hdalloc(&hpr)) == NULL)
130 goto memerr;
131 /* load beam directory */
132 n = nbeams(hp)*sizeof(BEAMI);
133 if (read(fd, (char *)(hp->bi+1), n) != n)
134 error(SYSTEM, "failure loading holodeck directory");
135 /* check that it's clean */
136 for (n = nbeams(hp); n > 0; n--)
137 if (hp->bi[n].fo < 0) {
138 hp->bi[n].fo = 0;
139 error(WARNING, "dirty holodeck section");
140 break;
141 }
142 } else { /* assume we're creating it */
143 if ((hp = hdalloc(hproto)) == NULL)
144 goto memerr;
145 /* write header and skeleton */
146 n = nbeams(hp)*sizeof(BEAMI);
147 if (write(fd, (char *)hproto, sizeof(HDGRID)) !=
148 sizeof(HDGRID) ||
149 write(fd, (char *)(hp->bi+1), n) != n)
150 error(SYSTEM, "cannot write header to holodeck file");
151 }
152 hp->fd = fd;
153 hp->dirty = 0;
154 biglob(hp)->fo = fpos + sizeof(HDGRID);
155 /* start tracking fragments */
156 hdattach(fd);
157 /* check rays on disk */
158 fpos = hdfilen(fd);
159 biglob(hp)->nrd = rtrunc = 0;
160 for (n = hproto == NULL ? nbeams(hp) : 0; n > 0; n--)
161 if (hp->bi[n].nrd)
162 if (hp->bi[n].fo+hp->bi[n].nrd*sizeof(RAYVAL) > fpos) {
163 rtrunc += hp->bi[n].nrd;
164 hp->bi[n].nrd = 0;
165 } else
166 biglob(hp)->nrd += hp->bi[n].nrd;
167 if (rtrunc) {
168 sprintf(errmsg, "truncated section, %ld rays lost (%.1f%%)",
169 rtrunc, 100.*rtrunc/(rtrunc+biglob(hp)->nrd));
170 error(WARNING, errmsg);
171 }
172 /* add to holodeck list */
173 for (n = 0; n < HDMAX; n++)
174 if (hdlist[n] == NULL) {
175 hdlist[n] = hp;
176 break;
177 }
178 /* all done */
179 return(hp);
180 memerr:
181 error(SYSTEM, "cannot allocate holodeck grid");
182 }
183
184
185 markdirty(hp, i) /* mark holodeck directory position dirty */
186 register HOLO *hp;
187 int i;
188 {
189 static BEAMI smudge = {0, -1};
190 int mindist, minpos;
191 register int j;
192
193 if (!hp->dirty++) { /* write smudge first time */
194 if (lseek(hp->fd, biglob(hp)->fo+(i-1)*sizeof(BEAMI), 0) < 0
195 || write(hp->fd, (char *)&smudge,
196 sizeof(BEAMI)) != sizeof(BEAMI))
197 error(SYSTEM, "seek/write error in markdirty");
198 hp->dirseg[0].s = i;
199 hp->dirseg[0].n = 1;
200 return;
201 }
202 /* insert into segment list */
203 for (j = hp->dirty; j--; ) {
204 if (!j || hp->dirseg[j-1].s < i) {
205 hp->dirseg[j].s = i;
206 hp->dirseg[j].n = 1;
207 break;
208 }
209 copystruct(hp->dirseg+j, hp->dirseg+(j-1));
210 }
211 do { /* check neighbors */
212 mindist = nbeams(hp); /* find closest */
213 for (j = hp->dirty; --j; )
214 if (hp->dirseg[j].s -
215 (hp->dirseg[j-1].s + hp->dirseg[j-1].n)
216 < mindist) {
217 minpos = j;
218 mindist = hp->dirseg[j].s -
219 (hp->dirseg[j-1].s + hp->dirseg[j-1].n);
220 }
221 /* good enough? */
222 if (hp->dirty <= MAXDIRSE && mindist > MINDIRSEL)
223 break;
224 j = minpos - 1; /* coalesce neighbors */
225 if (hp->dirseg[j].s + hp->dirseg[j].n <
226 hp->dirseg[minpos].s + hp->dirseg[minpos].n)
227 hp->dirseg[j].n = hp->dirseg[minpos].s +
228 hp->dirseg[minpos].n - hp->dirseg[j].s;
229 hp->dirty--;
230 while (++j < hp->dirty) /* close the gap */
231 copystruct(hp->dirseg+j, hp->dirseg+(j+1));
232 } while (mindist <= MINDIRSEL);
233 }
234
235
236 int
237 hdsync(hp, all) /* update beams and directory on disk */
238 register HOLO *hp;
239 int all;
240 {
241 register int j, n;
242
243 if (hp == NULL) { /* do all holodecks */
244 n = 0;
245 for (j = 0; hdlist[j] != NULL; j++)
246 n += hdsync(hdlist[j], all);
247 return(n);
248 }
249 /* sync the beams */
250 for (j = (all ? nbeams(hp) : 0); j > 0; j--)
251 if (hp->bl[j] != NULL)
252 hdsyncbeam(hp, j);
253 if (!hp->dirty) /* directory clean? */
254 return(0);
255 errno = 0; /* write dirty segments */
256 for (j = 0; j < hp->dirty; j++) {
257 if (lseek(hp->fd, biglob(hp)->fo +
258 (hp->dirseg[j].s-1)*sizeof(BEAMI), 0) < 0)
259 error(SYSTEM, "cannot seek on holodeck file");
260 n = hp->dirseg[j].n * sizeof(BEAMI);
261 if (write(hp->fd, (char *)(hp->bi+hp->dirseg[j].s), n) != n)
262 error(SYSTEM, "cannot update section directory");
263 }
264 hp->dirty = 0; /* all clean */
265 return(1);
266 }
267
268
269 unsigned
270 hdmemuse(all) /* return memory usage (in bytes) */
271 int all; /* include overhead (painful) */
272 {
273 long total = 0;
274 register int i, j;
275
276 for (j = 0; hdlist[j] != NULL; j++) {
277 total += blglob(hdlist[j])->nrm * sizeof(RAYVAL);
278 if (all) {
279 total += sizeof(HOLO) + sizeof(BEAM *) +
280 nbeams(hdlist[j]) *
281 (sizeof(BEAM *)+sizeof(BEAMI));
282 for (i = nbeams(hdlist[j]); i > 0; i--)
283 if (hdlist[j]->bl[i] != NULL)
284 total += sizeof(BEAM);
285 }
286 }
287 if (all)
288 for (j = 0; j < nhdfragls; j++) {
289 total += sizeof(struct fraglist);
290 if (hdfragl[j].nfrags)
291 total += FRAGBLK*sizeof(BEAMI) *
292 ((hdfragl[j].nfrags-1)/FRAGBLK + 1) ;
293 }
294 return(total);
295 }
296
297
298 long
299 hdfilen(fd) /* return file length for fd */
300 int fd;
301 {
302 long fpos, flen;
303
304 if (fd < 0)
305 return(-1);
306 if (fd >= nhdfragls || !hdfragl[fd].nlinks) {
307 if ((fpos = lseek(fd, 0L, 1)) < 0)
308 return(-1);
309 flen = lseek(fd, 0L, 2);
310 lseek(fd, fpos, 0);
311 return(flen);
312 }
313 return(hdfragl[fd].flen);
314 }
315
316
317 long
318 hdfiluse(fd, all) /* compute file usage (in bytes) */
319 int fd; /* open file descriptor to check */
320 int all; /* include overhead and unflushed data */
321 {
322 long total = 0;
323 register int i, j;
324
325 for (j = 0; hdlist[j] != NULL; j++) {
326 if (hdlist[j]->fd != fd)
327 continue;
328 total += biglob(hdlist[j])->nrd * sizeof(RAYVAL);
329 if (all) {
330 for (i = nbeams(hdlist[j]); i > 0; i--)
331 if (hdlist[j]->bl[i] != NULL)
332 total += sizeof(RAYVAL) *
333 (hdlist[j]->bl[i]->nrm -
334 hdlist[j]->bi[i].nrd);
335 total += sizeof(HDGRID) +
336 nbeams(hdlist[j])*sizeof(BEAMI);
337 }
338 }
339 return(total); /* does not include fragments */
340 }
341
342
343 RAYVAL *
344 hdnewrays(hp, i, nr) /* allocate space for add'l rays and return pointer */
345 register HOLO *hp;
346 register int i;
347 int nr; /* number of new rays desired */
348 {
349 RAYVAL *p;
350 int n;
351
352 if (nr <= 0)
353 return(NULL);
354 if (i < 1 | i > nbeams(hp))
355 error(CONSISTENCY, "bad beam index given to hdnewrays");
356 if (hp->bl[i] != NULL)
357 hp->bl[i]->tick = hdclock; /* preempt swap */
358 if (hdcachesize > 0 && hdmemuse(0) >= hdcachesize)
359 hdfreecache(PCTFREE, NULL); /* free some space */
360 if (hp->bl[i] == NULL) { /* allocate (and load) */
361 n = hp->bi[i].nrd + nr;
362 hp->bl[i] = (BEAM *)hdrealloc(NULL, hdbsiz(n), "hdnewrays");
363 blglob(hp)->nrm += n;
364 if (n = hp->bl[i]->nrm = hp->bi[i].nrd) {
365 errno = 0;
366 if (lseek(hp->fd, hp->bi[i].fo, 0) < 0)
367 error(SYSTEM, "seek error on holodeck file");
368 n *= sizeof(RAYVAL);
369 if (read(hp->fd, (char *)hdbray(hp->bl[i]), n) != n)
370 error(SYSTEM,
371 "error reading beam from holodeck file");
372 }
373 } else { /* just grow in memory */
374 hp->bl[i] = (BEAM *)hdrealloc((char *)hp->bl[i],
375 hdbsiz(hp->bl[i]->nrm + nr), "hdnewrays");
376 blglob(hp)->nrm += nr;
377 }
378 p = hdbray(hp->bl[i]) + hp->bl[i]->nrm;
379 hp->bl[i]->nrm += nr; /* update in-core structure */
380 bzero((char *)p, nr*sizeof(RAYVAL));
381 blglob(hp)->tick = hp->bl[i]->tick = hdclock++; /* update LRU clock */
382 return(p); /* point to new rays */
383 }
384
385
386 BEAM *
387 hdgetbeam(hp, i) /* get beam (from file if necessary) */
388 register HOLO *hp;
389 register int i;
390 {
391 register int n;
392
393 if (i < 1 | i > nbeams(hp))
394 error(CONSISTENCY, "bad beam index given to hdgetbeam");
395 if (hp->bl[i] == NULL) { /* load from disk */
396 if (!(n = hp->bi[i].nrd))
397 return(NULL);
398 if (hdcachesize > 0 && hdmemuse(0) >= hdcachesize)
399 hdfreecache(PCTFREE, NULL); /* get free space */
400 hp->bl[i] = (BEAM *)hdrealloc(NULL, hdbsiz(n), "hdgetbeam");
401 blglob(hp)->nrm += hp->bl[i]->nrm = n;
402 errno = 0;
403 if (lseek(hp->fd, hp->bi[i].fo, 0) < 0)
404 error(SYSTEM, "seek error on holodeck file");
405 n *= sizeof(RAYVAL);
406 if (read(hp->fd, (char *)hdbray(hp->bl[i]), n) != n)
407 error(SYSTEM, "error reading beam from holodeck file");
408 }
409 blglob(hp)->tick = hp->bl[i]->tick = hdclock++; /* update LRU clock */
410 return(hp->bl[i]);
411 }
412
413
414 int
415 hdfilord(hb1, hb2) /* order beams for quick loading */
416 register HDBEAMI *hb1, *hb2;
417 {
418 register long c;
419 /* residents go first */
420 if (hb2->h->bl[hb2->b] != NULL)
421 return(hb1->h->bl[hb1->b] == NULL);
422 if (hb1->h->bl[hb1->b] != NULL)
423 return(-1);
424 /* otherwise sort by file descriptor */
425 if ((c = hb1->h->fd - hb2->h->fd))
426 return(c);
427 /* then by position in file */
428 c = hb1->h->bi[hb1->b].fo - hb2->h->bi[hb2->b].fo;
429 return(c > 0 ? 1 : c < 0 ? -1 : 0);
430 }
431
432
433 hdloadbeams(hb, n, bf) /* load a list of beams in optimal order */
434 register HDBEAMI *hb; /* list gets sorted by hdfilord() */
435 int n; /* list length */
436 int (*bf)(); /* callback function (optional) */
437 {
438 unsigned origcachesize, memuse;
439 int bytesloaded, needbytes, bytes2free;
440 register BEAM *bp;
441 register int i;
442 /* precheck consistency */
443 if (n <= 0) return;
444 for (i = n; i--; )
445 if (hb[i].h == NULL || hb[i].b < 1 | hb[i].b > nbeams(hb[i].h))
446 error(CONSISTENCY, "bad beam in hdloadbeams");
447 /* sort list for optimal access */
448 qsort((char *)hb, n, sizeof(HDBEAMI), hdfilord);
449 bytesloaded = 0; /* run through loaded beams */
450 for ( ; n && (bp = hb->h->bl[hb->b]) != NULL; n--, hb++) {
451 bp->tick = hdclock; /* preempt swap */
452 bytesloaded += bp->nrm;
453 if (bf != NULL)
454 (*bf)(bp, hb);
455 }
456 bytesloaded *= sizeof(RAYVAL);
457 if ((origcachesize = hdcachesize) > 0) {
458 needbytes = 0; /* figure out memory needs */
459 for (i = n; i--; )
460 needbytes += hb[i].h->bi[hb[i].b].nrd;
461 needbytes *= sizeof(RAYVAL);
462 do { /* free enough memory */
463 memuse = hdmemuse(0);
464 bytes2free = needbytes - (int)(hdcachesize-memuse);
465 if (bytes2free > (int)(memuse - bytesloaded))
466 bytes2free = memuse - bytesloaded;
467 } while (bytes2free > 0 &&
468 hdfreecache(100*bytes2free/memuse, NULL) < 0);
469 hdcachesize = 0; /* load beams w/o swap */
470 }
471 for (i = 0; i < n; i++)
472 if ((bp = hdgetbeam(hb[i].h, hb[i].b)) != NULL && bf != NULL)
473 (*bf)(bp, hb+i);
474 hdcachesize = origcachesize; /* resume dynamic swapping */
475 }
476
477
478 hdfreefrag(fd, bi) /* free a file fragment */
479 int fd;
480 register BEAMI *bi;
481 {
482 register struct fraglist *f;
483 register int j, k;
484
485 if (bi->nrd == 0)
486 return;
487 #ifdef DEBUG
488 if (fd < 0 | fd >= nhdfragls || !hdfragl[fd].nlinks)
489 error(CONSISTENCY, "bad file descriptor in hdfreefrag");
490 #endif
491 f = &hdfragl[fd];
492 if (f->nfrags % FRAGBLK == 0) { /* delete empty remnants */
493 for (j = k = 0; k < f->nfrags; j++, k++) {
494 while (f->fi[k].nrd == 0)
495 if (++k >= f->nfrags)
496 goto endloop;
497 if (k > j)
498 copystruct(f->fi+j, f->fi+k);
499 }
500 endloop:
501 f->nfrags = j;
502 }
503 j = f->nfrags++; /* allocate a slot in free list */
504 #if MAXFRAG
505 if (j >= MAXFRAG-1)
506 f->nfrags--;
507 #endif
508 if (j % FRAGBLK == 0) { /* more free list space */
509 register BEAMI *newp;
510 if (f->fi == NULL)
511 newp = (BEAMI *)malloc((j+FRAGBLK)*sizeof(BEAMI));
512 else
513 newp = (BEAMI *)realloc((char *)f->fi,
514 (j+FRAGBLK)*sizeof(BEAMI));
515 if (newp == NULL) {
516 f->nfrags--; /* graceful failure */
517 return;
518 }
519 f->fi = newp;
520 }
521 for ( ; ; j--) { /* insert in descending list */
522 if (!j || bi->fo < f->fi[j-1].fo) {
523 f->fi[j].fo = bi->fo;
524 f->fi[j].nrd = bi->nrd;
525 break;
526 }
527 copystruct(f->fi+j, f->fi+(j-1));
528 }
529 /* coalesce adjacent fragments */
530 /* successors never empty */
531 if (j && f->fi[j-1].fo == f->fi[j].fo + f->fi[j].nrd*sizeof(RAYVAL)) {
532 f->fi[j].nrd += f->fi[j-1].nrd;
533 f->fi[j-1].nrd = 0;
534 }
535 for (k = j+1; k < f->nfrags; k++) /* get non-empty predecessor */
536 if (f->fi[k].nrd) {
537 if (f->fi[j].fo == f->fi[k].fo +
538 f->fi[k].nrd*sizeof(RAYVAL)) {
539 f->fi[k].nrd += f->fi[j].nrd;
540 f->fi[j].nrd = 0;
541 }
542 break;
543 }
544 }
545
546
547 long
548 hdallocfrag(fd, nrays) /* allocate a file fragment */
549 int fd;
550 unsigned int4 nrays;
551 {
552 register struct fraglist *f;
553 register int j, k;
554 long nfo;
555
556 if (nrays == 0)
557 return(-1L);
558 #ifdef DEBUG
559 if (fd < 0 | fd >= nhdfragls || !hdfragl[fd].nlinks)
560 error(CONSISTENCY, "bad file descriptor in hdallocfrag");
561 #endif
562 f = &hdfragl[fd];
563 k = -1; /* find closest-sized fragment */
564 for (j = f->nfrags; j-- > 0; )
565 if (f->fi[j].nrd >= nrays &&
566 (k < 0 || f->fi[j].nrd < f->fi[k].nrd))
567 if (f->fi[k=j].nrd == nrays)
568 break;
569 if (k < 0) { /* no fragment -- extend file */
570 nfo = f->flen;
571 f->flen += nrays*sizeof(RAYVAL);
572 } else { /* else use fragment */
573 nfo = f->fi[k].fo;
574 f->fi[k].fo += nrays*sizeof(RAYVAL);
575 f->fi[k].nrd -= nrays;
576 }
577 return(nfo);
578 }
579
580
581 int
582 hdsyncbeam(hp, i) /* sync beam in memory with beam on disk */
583 register HOLO *hp;
584 register int i;
585 {
586 unsigned int4 nrays;
587 unsigned int n;
588 long nfo;
589 /* check file status */
590 if (hdfragl[hp->fd].writerr)
591 return(-1);
592 #ifdef DEBUG
593 if (i < 1 | i > nbeams(hp))
594 error(CONSISTENCY, "bad beam index in hdsyncbeam");
595 #endif
596 /* is current fragment OK? */
597 if (hp->bl[i] == NULL || (nrays = hp->bl[i]->nrm) == hp->bi[i].nrd)
598 return(0);
599 if (hp->bi[i].nrd) /* relinquish old fragment */
600 hdfreefrag(hp->fd, &hp->bi[i]);
601 if (nrays) { /* get and write new fragment */
602 nfo = hdallocfrag(hp->fd, nrays);
603 errno = 0;
604 if (lseek(hp->fd, nfo, 0) < 0)
605 error(SYSTEM, "cannot seek on holodeck file");
606 n = hp->bl[i]->nrm * sizeof(RAYVAL);
607 if (write(hp->fd, (char *)hdbray(hp->bl[i]), n) != n) {
608 hdfragl[hp->fd].writerr++;
609 hdsync(NULL, 0); /* sync directories */
610 error(SYSTEM, "write error in hdsyncbeam");
611 }
612 hp->bi[i].fo = nfo;
613 } else
614 hp->bi[i].fo = 0L;
615 biglob(hp)->nrd += nrays - hp->bi[i].nrd;
616 hp->bi[i].nrd = nrays;
617 markdirty(hp, i); /* section directory now out of date */
618 return(1);
619 }
620
621
622 int
623 hdfreebeam(hp, i) /* free beam, writing if dirty */
624 register HOLO *hp;
625 register int i;
626 {
627 int nchanged;
628
629 if (hp == NULL) { /* clear all holodecks */
630 nchanged = 0;
631 for (i = 0; hdlist[i] != NULL; i++)
632 nchanged += hdfreebeam(hdlist[i], 0);
633 return(nchanged);
634 }
635 if (hdfragl[hp->fd].writerr) /* check for file error */
636 return(0);
637 if (i == 0) { /* clear entire holodeck */
638 nchanged = 0;
639 for (i = nbeams(hp); i > 0; i--)
640 if (hp->bl[i] != NULL)
641 nchanged += hdfreebeam(hp, i);
642 return(nchanged);
643 }
644 #ifdef DEBUG
645 if (i < 1 | i > nbeams(hp))
646 error(CONSISTENCY, "bad beam index to hdfreebeam");
647 #endif
648 if (hp->bl[i] == NULL)
649 return(0);
650 /* check for additions */
651 nchanged = hp->bl[i]->nrm - hp->bi[i].nrd;
652 if (nchanged)
653 hdsyncbeam(hp, i); /* write new fragment */
654 blglob(hp)->nrm -= hp->bl[i]->nrm;
655 free((char *)hp->bl[i]); /* free memory */
656 hp->bl[i] = NULL;
657 return(nchanged);
658 }
659
660
661 int
662 hdkillbeam(hp, i) /* delete beam from holodeck */
663 register HOLO *hp;
664 register int i;
665 {
666 static BEAM emptybeam;
667 int nchanged;
668
669 if (hp == NULL) { /* clobber all holodecks */
670 nchanged = 0;
671 for (i = 0; hdlist[i] != NULL; i++)
672 nchanged += hdkillbeam(hdlist[i], 0);
673 return(nchanged);
674 }
675 if (i == 0) { /* clobber entire holodeck */
676 nchanged = 0;
677 for (i = nbeams(hp); i > 0; i--)
678 if (hp->bi[i].nrd > 0 || hp->bl[i] != NULL)
679 nchanged += hdkillbeam(hp, i);
680 #ifdef DEBUG
681 if (biglob(hp)->nrd != 0 | blglob(hp)->nrm != 0)
682 error(CONSISTENCY, "bad beam count in hdkillbeam");
683 #endif
684 return(nchanged);
685 }
686 #ifdef DEBUG
687 if (i < 1 | i > nbeams(hp))
688 error(CONSISTENCY, "bad beam index to hdkillbeam");
689 #endif
690 if (hp->bl[i] != NULL) { /* free memory */
691 blglob(hp)->nrm -= nchanged = hp->bl[i]->nrm;
692 free((char *)hp->bl[i]);
693 } else
694 nchanged = hp->bi[i].nrd;
695 if (hp->bi[i].nrd) { /* free file fragment */
696 hp->bl[i] = &emptybeam;
697 hdsyncbeam(hp, i);
698 }
699 hp->bl[i] = NULL;
700 return(nchanged);
701 }
702
703
704 int
705 hdlrulist(hb, nents, n, hp) /* add beams from holodeck to LRU list */
706 register HDBEAMI *hb; /* beam list */
707 int nents; /* current list length */
708 int n; /* maximum list length */
709 register HOLO *hp; /* section we're adding from */
710 {
711 register int i, j;
712 /* insert each beam from hp */
713 for (i = 1; i <= nbeams(hp); i++) {
714 if (hp->bl[i] == NULL) /* check if loaded */
715 continue;
716 #if 0
717 if (hp->bl[i]->tick == hdclock) /* preempt swap? */
718 continue;
719 #endif
720 if ((j = ++nents) >= n) /* grow list if we can */
721 nents--;
722 for ( ; ; ) { /* bubble into place */
723 if (!--j || hp->bl[i]->tick >=
724 hb[j-1].h->bl[hb[j-1].b]->tick) {
725 hb[j].h = hp;
726 hb[j].b = i;
727 break;
728 }
729 copystruct(hb+j, hb+(j-1));
730 }
731 }
732 return(nents); /* return new list length */
733 }
734
735
736 int
737 hdfreecache(pct, honly) /* free up cache space, writing changes */
738 int pct; /* maximum percentage to free */
739 register HOLO *honly; /* NULL means check all */
740 {
741 HDBEAMI hb[FREEBEAMS];
742 int freetarget;
743 int n;
744 register int i;
745 #ifdef DEBUG
746 unsigned membefore;
747
748 membefore = hdmemuse(0);
749 #endif
750 /* compute free target */
751 freetarget = (honly != NULL) ? blglob(honly)->nrm :
752 hdmemuse(0)/sizeof(RAYVAL) ;
753 freetarget = freetarget*pct/100;
754 if (freetarget <= 0)
755 return(0);
756 /* find least recently used */
757 n = 0;
758 if (honly != NULL)
759 n = hdlrulist(hb, n, FREEBEAMS, honly);
760 else
761 for (i = 0; hdlist[i] != NULL; i++)
762 n = hdlrulist(hb, n, FREEBEAMS, hdlist[i]);
763 /* free LRU beams */
764 for (i = 0; i < n; i++) {
765 hdfreebeam(hb[i].h, hb[i].b);
766 if ((freetarget -= hb[i].h->bi[hb[i].b].nrd) <= 0)
767 break;
768 }
769 hdsync(honly, 0); /* synchronize directories as necessary */
770 #ifdef DEBUG
771 sprintf(errmsg,
772 "%dK before, %dK after hdfreecache (%dK total), %d rays short\n",
773 membefore>>10, hdmemuse(0)>>10, hdmemuse(1)>>10, freetarget);
774 wputs(errmsg);
775 #endif
776 return(-freetarget); /* return how far past goal we went */
777 }
778
779
780 hddone(hp) /* clean up holodeck section and free */
781 register HOLO *hp; /* NULL means clean up all */
782 {
783 register int i;
784
785 if (hp == NULL) { /* NULL means clean up everything */
786 while (hdlist[0] != NULL)
787 hddone(hdlist[0]);
788 free((char *)hdfragl);
789 hdfragl = NULL; nhdfragls = 0;
790 return;
791 }
792 /* flush all data and free memory */
793 hdfreebeam(hp, 0);
794 hdsync(hp, 0);
795 /* release fragment resources */
796 hdrelease(hp->fd);
797 /* remove hp from active list */
798 for (i = 0; hdlist[i] != NULL; i++)
799 if (hdlist[i] == hp) {
800 while ((hdlist[i] = hdlist[i+1]) != NULL)
801 i++;
802 break;
803 }
804 free((char *)hp->bl); /* free beam list */
805 free((char *)hp); /* free holodeck struct */
806 }