bsd/net/bsd_comp.c

165 static void	bsd_clear(struct bsd_db *db);
166 static int	bsd_check(struct bsd_db *db);
168 static int	bsd_init_comp_db(struct bsd_db *db, u_char *options,
233 bsd_clear(db)
234     struct bsd_db *db;
236     db->clear_count++;
237     db->max_ent = FIRST-1;
238     db->n_bits = BSD_INIT_BITS;
239     db->ratio = 0;
240     db->bytes_out = 0;
241     db->in_count = 0;
242     db->checkpoint = CHECK_GAP;
259 bsd_check(db)
260     struct bsd_db *db;
264     if (db->in_count >= db->checkpoint) {
266 	if (db->in_count >= RATIO_MAX
267 	    || db->bytes_out >= RATIO_MAX) {
268 	    db->in_count -= db->in_count/4;
269 	    db->bytes_out -= db->bytes_out/4;
272 	db->checkpoint = db->in_count + CHECK_GAP;
274 	if (db->max_ent >= db->maxmaxcode) {
280 	     *	db->in_count <= RATIO_MAX.
282 	    new_ratio = db->in_count << RATIO_SCALE_LOG;
283 	    if (db->bytes_out != 0)
284 		new_ratio /= db->bytes_out;
286 	    if (new_ratio < db->ratio || new_ratio < 1 * RATIO_SCALE) {
287 		bsd_clear(db);
290 	    db->ratio = new_ratio;
304     struct bsd_db *db = (struct bsd_db *) state;
307     stats->unc_bytes = db->uncomp_bytes;
308     stats->unc_packets = db->uncomp_count;
309     stats->comp_bytes = db->comp_bytes;
310     stats->comp_packets = db->comp_count;
311     stats->inc_bytes = db->incomp_bytes;
312     stats->inc_packets = db->incomp_count;
313     stats->ratio = db->in_count;
314     out = db->bytes_out;
330     struct bsd_db *db = (struct bsd_db *) state;
332     db->seqno = 0;
333     bsd_clear(db);
334     db->clear_count = 0;
347     struct bsd_db *db;
383     newlen = sizeof(*db) + (hsize-1) * (sizeof(db->dict[0]));
384     MALLOC(db, struct bsd_db *, newlen, M_DEVBUF, M_NOWAIT);
385     if (!db)
387     bzero(db, sizeof(*db) - sizeof(db->dict));
390 	db->lens = NULL;
392 	MALLOC(db->lens, u_int16_t *, (maxmaxcode+1) * sizeof(db->lens[0]),
394 	if (!db->lens) {
395 	    FREE(db, M_DEVBUF);
400     db->totlen = newlen;
401     db->hsize = hsize;
402     db->hshift = hshift;
403     db->maxmaxcode = maxmaxcode;
404     db->maxbits = bits;
406     return (void *) db;
413     struct bsd_db *db = (struct bsd_db *) state;
415     if (db->lens)
416 	FREE(db->lens, M_DEVBUF);
417     FREE(db, M_DEVBUF);
440 bsd_init_comp_db(db, options, opt_len, unit, hdrlen, mru, debug, decomp)
441     struct bsd_db *db;
450 	|| BSD_NBITS(options[2]) != db->maxbits
451 	|| (decomp && db->lens == NULL))
457 	    db->lens[--i] = 1;
459     i = db->hsize;
461 	db->dict[--i].codem1 = BADCODEM1;
462 	db->dict[i].cptr = 0;
465     db->unit = unit;
466     db->hdrlen = hdrlen;
467     db->mru = mru;
471         db->debug = 1;
473     bsd_reset(db);
512     struct bsd_db *db = (struct bsd_db *) state;
513     int hshift = db->hshift;
514     u_int max_ent = db->max_ent;
515     u_int n_bits = db->n_bits;
578 	if (maxolen + db->hdrlen > MLEN)
580 	m->m_data += db->hdrlen;
595 	*wptr++ = db->seqno >> 8;
596 	*wptr++ = db->seqno;
598     ++db->seqno;
620 	dictp = &db->dict[hval];
634 	    if (hval >= db->hsize)
635 		hval -= db->hsize;
636 	    dictp = &db->dict[hval];
647 	if (max_ent < db->maxmaxcode) {
651 		db->n_bits = ++n_bits;
656 	    dictp2 = &db->dict[max_ent+1];
657 	    if (db->dict[dictp2->cptr].codem1 == max_ent)
658 		db->dict[dictp2->cptr].codem1 = BADCODEM1;
663 	    db->max_ent = ++max_ent;
669     db->bytes_out += olen;
670     db->in_count += ilen;
672 	++db->bytes_out;	/* count complete bytes */
674     if (bsd_check(db))
693     if (max_ent >= MAXCODE(n_bits) && max_ent < db->maxmaxcode)
694 	db->n_bits++;
696     db->uncomp_bytes += ilen;
697     ++db->uncomp_count;
704 	++db->incomp_count;
705 	db->incomp_bytes += ilen;
707 	++db->comp_count;
708 	db->comp_bytes += olen + BSD_OVHD;
726     struct bsd_db *db = (struct bsd_db *) state;
727     u_int hshift = db->hshift;
728     u_int max_ent = db->max_ent;
729     u_int n_bits = db->n_bits;
749     db->seqno++;
768 	    dictp = &db->dict[hval];
782 		if (hval >= db->hsize)
783 		    hval -= db->hsize;
784 		dictp = &db->dict[hval];
795 	    if (max_ent < db->maxmaxcode) {
799 		    db->n_bits = ++n_bits;
804 		dictp2 = &db->dict[max_ent+1];
805 		if (db->dict[dictp2->cptr].codem1 == max_ent)
806 		    db->dict[dictp2->cptr].codem1 = BADCODEM1;
811 		db->max_ent = ++max_ent;
812 		db->lens[max_ent] = db->lens[ent]+1;
818     db->bytes_out += bitno/8;
819     db->in_count += ilen;
820     (void)bsd_check(db);
822     ++db->incomp_count;
823     db->incomp_bytes += ilen;
824     ++db->uncomp_count;
825     db->uncomp_bytes += ilen;
830     if (max_ent >= MAXCODE(n_bits) && max_ent < db->maxmaxcode)
831 	db->n_bits++;
856     struct bsd_db *db = (struct bsd_db *) state;
857     u_int max_ent = db->max_ent;
860     u_int n_bits = db->n_bits;
897     if (seq != db->seqno) {
898 	if (db->debug)
900 		   db->unit, seq, db->seqno - 1);
903     ++db->seqno;
915     dmp->m_data += db->hdrlen;
970 		    if (db->debug)
971 			printf("bsd_decomp%d: bad CLEAR\n", db->unit);
975 	    bsd_clear(db);
980 	if (incode > max_ent + 2 || incode > db->maxmaxcode
983 	    if (db->debug) {
985 		       db->unit, incode, oldcode);
987 		       max_ent, explen, db->seqno);
1001 	codelen = db->lens[finchar];
1003 	if (explen > db->mru + 1) {
1005 	    if (db->debug) {
1006 		printf("bsd_decomp%d: ran out of mru\n", db->unit);
1047 	    dictp = &db->dict[db->dict[finchar].cptr];
1060 		   db->unit, codelen, incode, max_ent);
1073 	if (oldcode != CLEAR && max_ent < db->maxmaxcode) {
1079 	    hval = BSD_HASH(oldcode,finchar,db->hshift);
1080 	    dictp = &db->dict[hval];
1087 		    if (hval >= db->hsize)
1088 			hval -= db->hsize;
1089 		    dictp = &db->dict[hval];
1097 	    dictp2 = &db->dict[max_ent+1];
1098 	    if (db->dict[dictp2->cptr].codem1 == max_ent) {
1099 		db->dict[dictp2->cptr].codem1 = BADCODEM1;
1105 	    db->max_ent = ++max_ent;
1106 	    db->lens[max_ent] = db->lens[oldcode]+1;
1109 	    if (max_ent >= MAXCODE(n_bits) && max_ent < db->maxmaxcode) {
1110 		db->n_bits = ++n_bits;
1122     db->bytes_out += ilen;
1123     db->in_count += explen;
1124     if (bsd_check(db) && db->debug) {
1126 	       db->unit);
1129     ++db->comp_count;
1130     db->comp_bytes += ilen + BSD_OVHD;
1131     ++db->uncomp_count;
1132     db->uncomp_bytes += explen;
1140 	printf("bsd_decomp%d: fell off end of chain ", db->unit);
1142 	       incode, finchar, db->dict[finchar].cptr, max_ent);
1145 	       db->unit, incode, finchar);
1147 	       db->dict[finchar].cptr, dictp->codem1);