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- #include <sys/param.h>
- #include <sys/types.h>
- #include <sys/systm.h>
- #include <sys/mbuf.h>
- #include <sys/socket.h>
- #include <net/if.h>
- #include <net/if_var.h>
- #include <net/if_types.h>
- #include <net/ppp_defs.h>
- #include <net/if_ppp.h>
- #define PACKETPTR struct mbuf *
- #include <net/ppp-comp.h>
- #if DO_BSD_COMPRESS
- struct bsd_db {
- int totlen;
- u_int hsize;
- u_char hshift;
- u_char n_bits;
- u_char maxbits;
- u_char debug;
- u_char unit;
- u_int16_t seqno;
- u_int hdrlen;
- u_int mru;
- u_int maxmaxcode;
- u_int max_ent;
- u_int in_count;
- u_int bytes_out;
- u_int ratio;
- u_int checkpoint;
- u_int clear_count;
- u_int incomp_count;
- u_int incomp_bytes;
- u_int uncomp_count;
- u_int uncomp_bytes;
- u_int comp_count;
- u_int comp_bytes;
- u_int16_t *lens;
- struct bsd_dict {
- union {
- u_int32_t fcode;
- struct {
- #if BYTE_ORDER == LITTLE_ENDIAN
- u_int16_t prefix;
- u_char suffix;
- u_char pad;
- #else
- u_char pad;
- u_char suffix;
- u_int16_t prefix;
- #endif
- } hs;
- } f;
- u_int16_t codem1;
- u_int16_t cptr;
- } dict[1];
- };
- #define BSD_OVHD 2
- #define BSD_INIT_BITS BSD_MIN_BITS
- static void *bsd_comp_alloc(u_char *options, int opt_len);
- static void *bsd_decomp_alloc(u_char *options, int opt_len);
- static void bsd_free(void *state);
- static int bsd_comp_init(void *state, u_char *options, int opt_len,
- int unit, int hdrlen, int debug);
- static int bsd_decomp_init(void *state, u_char *options, int opt_len,
- int unit, int hdrlen, int mru, int debug);
- static int bsd_compress(void *state, struct mbuf **mret,
- struct mbuf *mp, int slen, int maxolen);
- static void bsd_incomp(void *state, struct mbuf *dmsg);
- static int bsd_decompress(void *state, struct mbuf *cmp,
- struct mbuf **dmpp);
- static void bsd_reset(void *state);
- static void bsd_comp_stats(void *state, struct compstat *stats);
- struct compressor ppp_bsd_compress = {
- CI_BSD_COMPRESS,
- bsd_comp_alloc,
- bsd_free,
- bsd_comp_init,
- bsd_reset,
- bsd_compress,
- bsd_comp_stats,
- bsd_decomp_alloc,
- bsd_free,
- bsd_decomp_init,
- bsd_reset,
- bsd_decompress,
- bsd_incomp,
- bsd_comp_stats,
- };
- #define CLEAR 256
- #define FIRST 257
- #define LAST 255
- #define MAXCODE(b) ((1 << (b)) - 1)
- #define BADCODEM1 MAXCODE(BSD_MAX_BITS)
- #define BSD_HASH(prefix,suffix,hshift) ((((u_int32_t)(suffix)) << (hshift)) \
- ^ (u_int32_t)(prefix))
- #define BSD_KEY(prefix,suffix) ((((u_int32_t)(suffix)) << 16) \
- + (u_int32_t)(prefix))
- #define CHECK_GAP 10000 /* Ratio check interval */
- #define RATIO_SCALE_LOG 8
- #define RATIO_SCALE (1<<RATIO_SCALE_LOG)
- #define RATIO_MAX (0x7fffffff>>RATIO_SCALE_LOG)
- static void bsd_clear(struct bsd_db *);
- static int bsd_check(struct bsd_db *);
- static void *bsd_alloc(u_char *, int, int);
- static int bsd_init(struct bsd_db *, u_char *, int, int, int, int,
- int, int);
- static void
- bsd_clear(db)
- struct bsd_db *db;
- {
- db->clear_count++;
- db->max_ent = FIRST-1;
- db->n_bits = BSD_INIT_BITS;
- db->ratio = 0;
- db->bytes_out = 0;
- db->in_count = 0;
- db->incomp_count = 0;
- db->checkpoint = CHECK_GAP;
- }
- static int
- bsd_check(db)
- struct bsd_db *db;
- {
- u_int new_ratio;
- if (db->in_count >= db->checkpoint) {
-
- if (db->in_count >= RATIO_MAX
- || db->bytes_out >= RATIO_MAX) {
- db->in_count -= db->in_count/4;
- db->bytes_out -= db->bytes_out/4;
- }
- db->checkpoint = db->in_count + CHECK_GAP;
- if (db->max_ent >= db->maxmaxcode) {
-
- new_ratio = db->in_count << RATIO_SCALE_LOG;
- if (db->bytes_out != 0)
- new_ratio /= db->bytes_out;
- if (new_ratio < db->ratio || new_ratio < 1 * RATIO_SCALE) {
- bsd_clear(db);
- return 1;
- }
- db->ratio = new_ratio;
- }
- }
- return 0;
- }
- static void
- bsd_comp_stats(state, stats)
- void *state;
- struct compstat *stats;
- {
- struct bsd_db *db = (struct bsd_db *) state;
- u_int out;
- stats->unc_bytes = db->uncomp_bytes;
- stats->unc_packets = db->uncomp_count;
- stats->comp_bytes = db->comp_bytes;
- stats->comp_packets = db->comp_count;
- stats->inc_bytes = db->incomp_bytes;
- stats->inc_packets = db->incomp_count;
- stats->ratio = db->in_count;
- out = db->bytes_out;
- if (stats->ratio <= 0x7fffff)
- stats->ratio <<= 8;
- else
- out >>= 8;
- if (out != 0)
- stats->ratio /= out;
- }
- static void
- bsd_reset(state)
- void *state;
- {
- struct bsd_db *db = (struct bsd_db *) state;
- db->seqno = 0;
- bsd_clear(db);
- db->clear_count = 0;
- }
- static void *
- bsd_alloc(options, opt_len, decomp)
- u_char *options;
- int opt_len, decomp;
- {
- int bits;
- u_int newlen, hsize, hshift, maxmaxcode;
- struct bsd_db *db;
- if (opt_len < CILEN_BSD_COMPRESS || options[0] != CI_BSD_COMPRESS
- || options[1] != CILEN_BSD_COMPRESS
- || BSD_VERSION(options[2]) != BSD_CURRENT_VERSION)
- return NULL;
- bits = BSD_NBITS(options[2]);
- switch (bits) {
- case 9:
- case 10:
- case 11:
- case 12:
- hsize = 5003;
- hshift = 4;
- break;
- case 13:
- hsize = 9001;
- hshift = 5;
- break;
- case 14:
- hsize = 18013;
- hshift = 6;
- break;
- case 15:
- hsize = 35023;
- hshift = 7;
- break;
- case 16:
-
-
-
- default:
- return NULL;
- }
- maxmaxcode = MAXCODE(bits);
- newlen = sizeof(*db) + (hsize-1) * (sizeof(db->dict[0]));
- db = malloc(newlen, M_DEVBUF, M_NOWAIT|M_ZERO);
- if (!db)
- return NULL;
- if (!decomp) {
- db->lens = NULL;
- } else {
- db->lens = mallocarray(maxmaxcode + 1, sizeof(db->lens[0]), M_DEVBUF,
- M_NOWAIT);
- if (!db->lens) {
- free(db, M_DEVBUF, 0);
- return NULL;
- }
- }
- db->totlen = newlen;
- db->hsize = hsize;
- db->hshift = hshift;
- db->maxmaxcode = maxmaxcode;
- db->maxbits = bits;
- return (void *) db;
- }
- static void
- bsd_free(state)
- void *state;
- {
- struct bsd_db *db = (struct bsd_db *) state;
- if (db->lens)
- free(db->lens, M_DEVBUF, 0);
- free(db, M_DEVBUF, 0);
- }
- static void *
- bsd_comp_alloc(options, opt_len)
- u_char *options;
- int opt_len;
- {
- return bsd_alloc(options, opt_len, 0);
- }
- static void *
- bsd_decomp_alloc(options, opt_len)
- u_char *options;
- int opt_len;
- {
- return bsd_alloc(options, opt_len, 1);
- }
- static int
- bsd_init(db, options, opt_len, unit, hdrlen, mru, debug, decomp)
- struct bsd_db *db;
- u_char *options;
- int opt_len, unit, hdrlen, mru, debug, decomp;
- {
- int i;
- if (opt_len < CILEN_BSD_COMPRESS || options[0] != CI_BSD_COMPRESS
- || options[1] != CILEN_BSD_COMPRESS
- || BSD_VERSION(options[2]) != BSD_CURRENT_VERSION
- || BSD_NBITS(options[2]) != db->maxbits
- || (decomp && db->lens == NULL))
- return 0;
- if (decomp) {
- i = LAST+1;
- while (i != 0)
- db->lens[--i] = 1;
- }
- i = db->hsize;
- while (i != 0) {
- db->dict[--i].codem1 = BADCODEM1;
- db->dict[i].cptr = 0;
- }
- db->unit = unit;
- db->hdrlen = hdrlen;
- db->mru = mru;
- #ifndef DEBUG
- if (debug)
- #endif
- db->debug = 1;
- bsd_reset(db);
- return 1;
- }
- static int
- bsd_comp_init(state, options, opt_len, unit, hdrlen, debug)
- void *state;
- u_char *options;
- int opt_len, unit, hdrlen, debug;
- {
- return bsd_init((struct bsd_db *) state, options, opt_len,
- unit, hdrlen, 0, debug, 0);
- }
- static int
- bsd_decomp_init(state, options, opt_len, unit, hdrlen, mru, debug)
- void *state;
- u_char *options;
- int opt_len, unit, hdrlen, mru, debug;
- {
- return bsd_init((struct bsd_db *) state, options, opt_len,
- unit, hdrlen, mru, debug, 1);
- }
- int
- bsd_compress(state, mret, mp, slen, maxolen)
- void *state;
- struct mbuf **mret;
- struct mbuf *mp;
- int slen;
- int maxolen;
- {
- struct bsd_db *db = (struct bsd_db *) state;
- int hshift = db->hshift;
- u_int max_ent = db->max_ent;
- u_int n_bits = db->n_bits;
- u_int bitno = 32;
- u_int32_t accm = 0, fcode;
- struct bsd_dict *dictp;
- u_char c;
- int hval, disp, ent, ilen;
- u_char *rptr, *wptr;
- u_char *cp_end;
- int olen;
- struct mbuf *m;
- #define PUTBYTE(v) { \
- ++olen; \
- if (wptr) { \
- *wptr++ = (v); \
- if (wptr >= cp_end) { \
- m->m_len = wptr - mtod(m, u_char *); \
- MGET(m->m_next, M_DONTWAIT, MT_DATA); \
- m = m->m_next; \
- if (m) { \
- m->m_len = 0; \
- if (maxolen - olen > MLEN) \
- MCLGET(m, M_DONTWAIT); \
- wptr = mtod(m, u_char *); \
- cp_end = wptr + M_TRAILINGSPACE(m); \
- } else \
- wptr = NULL; \
- } \
- } \
- }
- #define OUTPUT(ent) { \
- bitno -= n_bits; \
- accm |= ((ent) << bitno); \
- do { \
- PUTBYTE(accm >> 24); \
- accm <<= 8; \
- bitno += 8; \
- } while (bitno <= 24); \
- }
- /*
- * If the protocol is not in the range we're interested in,
- * just return without compressing the packet. If it is,
- * the protocol becomes the first byte to compress.
- */
- rptr = mtod(mp, u_char *);
- ent = PPP_PROTOCOL(rptr);
- if (ent < 0x21 || ent > 0xf9) {
- *mret = NULL;
- return slen;
- }
-
- if (maxolen > slen)
- maxolen = slen;
-
- MGET(m, M_DONTWAIT, MT_DATA);
- *mret = m;
- if (m != NULL) {
- m->m_len = 0;
- if (maxolen + db->hdrlen > MLEN)
- MCLGET(m, M_DONTWAIT);
- m->m_data += db->hdrlen;
- wptr = mtod(m, u_char *);
- cp_end = wptr + M_TRAILINGSPACE(m);
- } else
- wptr = cp_end = NULL;
-
- if (wptr) {
- *wptr++ = PPP_ADDRESS(rptr);
- *wptr++ = PPP_CONTROL(rptr);
- *wptr++ = 0;
- *wptr++ = PPP_COMP;
- *wptr++ = db->seqno >> 8;
- *wptr++ = db->seqno;
- }
- ++db->seqno;
- olen = 0;
- rptr += PPP_HDRLEN;
- slen = mp->m_len - PPP_HDRLEN;
- ilen = slen + 1;
- for (;;) {
- if (slen <= 0) {
- mp = mp->m_next;
- if (!mp)
- break;
- rptr = mtod(mp, u_char *);
- slen = mp->m_len;
- if (!slen)
- continue;
- ilen += slen;
- }
- slen--;
- c = *rptr++;
- fcode = BSD_KEY(ent, c);
- hval = BSD_HASH(ent, c, hshift);
- dictp = &db->dict[hval];
-
- if (dictp->codem1 >= max_ent)
- goto nomatch;
- if (dictp->f.fcode == fcode) {
- ent = dictp->codem1+1;
- continue;
- }
-
- disp = (hval == 0) ? 1 : hval;
- do {
- hval += disp;
- if (hval >= db->hsize)
- hval -= db->hsize;
- dictp = &db->dict[hval];
- if (dictp->codem1 >= max_ent)
- goto nomatch;
- } while (dictp->f.fcode != fcode);
- ent = dictp->codem1 + 1;
- continue;
- nomatch:
- OUTPUT(ent);
-
- if (max_ent < db->maxmaxcode) {
- struct bsd_dict *dictp2;
-
- if (max_ent >= MAXCODE(n_bits))
- db->n_bits = ++n_bits;
-
- dictp2 = &db->dict[max_ent+1];
- if (db->dict[dictp2->cptr].codem1 == max_ent)
- db->dict[dictp2->cptr].codem1 = BADCODEM1;
- dictp2->cptr = hval;
- dictp->codem1 = max_ent;
- dictp->f.fcode = fcode;
- db->max_ent = ++max_ent;
- }
- ent = c;
- }
- OUTPUT(ent);
- db->bytes_out += olen;
- db->in_count += ilen;
- if (bitno < 32)
- ++db->bytes_out;
- if (bsd_check(db))
- OUTPUT(CLEAR);
-
- if (bitno != 32)
- PUTBYTE((accm | (0xff << (bitno-8))) >> 24);
- if (m != NULL) {
- m->m_len = wptr - mtod(m, u_char *);
- m->m_next = NULL;
- }
-
- if (max_ent >= MAXCODE(n_bits) && max_ent < db->maxmaxcode)
- db->n_bits++;
- db->uncomp_bytes += ilen;
- ++db->uncomp_count;
- if (olen + PPP_HDRLEN + BSD_OVHD > maxolen) {
-
- m_freem(*mret);
- *mret = NULL;
- ++db->incomp_count;
- db->incomp_bytes += ilen;
- } else {
- ++db->comp_count;
- db->comp_bytes += olen + BSD_OVHD;
- }
- return olen + PPP_HDRLEN + BSD_OVHD;
- #undef OUTPUT
- #undef PUTBYTE
- }
- static void
- bsd_incomp(state, dmsg)
- void *state;
- struct mbuf *dmsg;
- {
- struct bsd_db *db = (struct bsd_db *) state;
- u_int hshift = db->hshift;
- u_int max_ent = db->max_ent;
- u_int n_bits = db->n_bits;
- struct bsd_dict *dictp;
- u_int32_t fcode;
- u_char c;
- u_int32_t hval, disp;
- int slen, ilen;
- u_int bitno = 7;
- u_char *rptr;
- u_int ent;
-
- rptr = mtod(dmsg, u_char *);
- ent = PPP_PROTOCOL(rptr);
- if (ent < 0x21 || ent > 0xf9)
- return;
- db->incomp_count++;
- db->seqno++;
- ilen = 1;
- rptr += PPP_HDRLEN;
- slen = dmsg->m_len - PPP_HDRLEN;
- for (;;) {
- if (slen <= 0) {
- dmsg = dmsg->m_next;
- if (!dmsg)
- break;
- rptr = mtod(dmsg, u_char *);
- slen = dmsg->m_len;
- continue;
- }
- ilen += slen;
- do {
- c = *rptr++;
- fcode = BSD_KEY(ent, c);
- hval = BSD_HASH(ent, c, hshift);
- dictp = &db->dict[hval];
-
- if (dictp->codem1 >= max_ent)
- goto nomatch;
- if (dictp->f.fcode == fcode) {
- ent = dictp->codem1+1;
- continue;
- }
-
- disp = (hval == 0) ? 1 : hval;
- do {
- hval += disp;
- if (hval >= db->hsize)
- hval -= db->hsize;
- dictp = &db->dict[hval];
- if (dictp->codem1 >= max_ent)
- goto nomatch;
- } while (dictp->f.fcode != fcode);
- ent = dictp->codem1+1;
- continue;
- nomatch:
- bitno += n_bits;
-
- if (max_ent < db->maxmaxcode) {
- struct bsd_dict *dictp2;
-
- if (max_ent >= MAXCODE(n_bits))
- db->n_bits = ++n_bits;
-
- dictp2 = &db->dict[max_ent+1];
- if (db->dict[dictp2->cptr].codem1 == max_ent)
- db->dict[dictp2->cptr].codem1 = BADCODEM1;
- dictp2->cptr = hval;
- dictp->codem1 = max_ent;
- dictp->f.fcode = fcode;
- db->max_ent = ++max_ent;
- db->lens[max_ent] = db->lens[ent]+1;
- }
- ent = c;
- } while (--slen != 0);
- }
- bitno += n_bits;
- db->bytes_out += bitno/8;
- db->in_count += ilen;
- (void)bsd_check(db);
- ++db->incomp_count;
- db->incomp_bytes += ilen;
- ++db->uncomp_count;
- db->uncomp_bytes += ilen;
-
- if (max_ent >= MAXCODE(n_bits) && max_ent < db->maxmaxcode)
- db->n_bits++;
- }
- int
- bsd_decompress(state, cmp, dmpp)
- void *state;
- struct mbuf *cmp, **dmpp;
- {
- struct bsd_db *db = (struct bsd_db *) state;
- u_int max_ent = db->max_ent;
- u_int32_t accm = 0;
- u_int bitno = 32;
- u_int n_bits = db->n_bits;
- u_int tgtbitno = 32-n_bits;
- struct bsd_dict *dictp;
- int explen, i, seq, len;
- u_int incode, oldcode, finchar;
- u_char *p, *rptr, *wptr;
- struct mbuf *m, *dmp, *mret;
- int adrs, ctrl, ilen;
- int space, codelen, extra;
-
- *dmpp = NULL;
- rptr = mtod(cmp, u_char *);
- adrs = PPP_ADDRESS(rptr);
- ctrl = PPP_CONTROL(rptr);
- rptr += PPP_HDRLEN;
- len = cmp->m_len - PPP_HDRLEN;
- seq = 0;
- for (i = 0; i < 2; ++i) {
- while (len <= 0) {
- cmp = cmp->m_next;
- if (cmp == NULL)
- return DECOMP_ERROR;
- rptr = mtod(cmp, u_char *);
- len = cmp->m_len;
- }
- seq = (seq << 8) + *rptr++;
- --len;
- }
-
- if (seq != db->seqno) {
- if (db->debug)
- printf("bsd_decomp%d: bad sequence # %d, expected %d\n",
- db->unit, seq, db->seqno - 1);
- return DECOMP_ERROR;
- }
- ++db->seqno;
-
- MGETHDR(dmp, M_DONTWAIT, MT_DATA);
- if (dmp == NULL)
- return DECOMP_ERROR;
- mret = dmp;
- dmp->m_len = 0;
- dmp->m_next = NULL;
- MCLGET(dmp, M_DONTWAIT);
- dmp->m_data += db->hdrlen;
- wptr = mtod(dmp, u_char *);
- space = M_TRAILINGSPACE(dmp) - PPP_HDRLEN + 1;
-
- wptr[0] = adrs;
- wptr[1] = ctrl;
- wptr[2] = 0;
- wptr += PPP_HDRLEN - 1;
- ilen = len;
- oldcode = CLEAR;
- explen = 0;
- for (;;) {
- if (len == 0) {
- cmp = cmp->m_next;
- if (!cmp)
- break;
- rptr = mtod(cmp, u_char *);
- len = cmp->m_len;
- ilen += len;
- continue;
- }
-
- bitno -= 8;
- accm |= *rptr++ << bitno;
- --len;
- if (tgtbitno < bitno)
- continue;
- incode = accm >> tgtbitno;
- accm <<= n_bits;
- bitno += n_bits;
- if (incode == CLEAR) {
-
- if (len > 0 || cmp->m_next != NULL) {
- while ((cmp = cmp->m_next) != NULL)
- len += cmp->m_len;
- if (len > 0) {
- m_freem(mret);
- if (db->debug)
- printf("bsd_decomp%d: bad CLEAR\n", db->unit);
- return DECOMP_FATALERROR;
- }
- }
- bsd_clear(db);
- explen = ilen = 0;
- break;
- }
- if (incode > max_ent + 2 || incode > db->maxmaxcode
- || (incode > max_ent && oldcode == CLEAR)) {
- m_freem(mret);
- if (db->debug) {
- printf("bsd_decomp%d: bad code 0x%x oldcode=0x%x ",
- db->unit, incode, oldcode);
- printf("max_ent=0x%x explen=%d seqno=%d\n",
- max_ent, explen, db->seqno);
- }
- return DECOMP_FATALERROR;
- }
-
- if (incode > max_ent) {
- finchar = oldcode;
- extra = 1;
- } else {
- finchar = incode;
- extra = 0;
- }
- codelen = db->lens[finchar];
- explen += codelen + extra;
- if (explen > db->mru + 1) {
- m_freem(mret);
- if (db->debug) {
- printf("bsd_decomp%d: ran out of mru\n", db->unit);
- #ifdef DEBUG
- while ((cmp = cmp->m_next) != NULL)
- len += cmp->m_len;
- printf(" len=%d, finchar=0x%x, codelen=%d, explen=%d\n",
- len, finchar, codelen, explen);
- #endif
- }
- return DECOMP_FATALERROR;
- }
-
- if ((space -= codelen + extra) < 0) {
- dmp->m_len = wptr - mtod(dmp, u_char *);
- MGET(m, M_DONTWAIT, MT_DATA);
- if (m == NULL) {
- m_freem(mret);
- return DECOMP_ERROR;
- }
- m->m_len = 0;
- m->m_next = NULL;
- dmp->m_next = m;
- MCLGET(m, M_DONTWAIT);
- space = M_TRAILINGSPACE(m) - (codelen + extra);
- if (space < 0) {
-
- m_freem(mret);
- return DECOMP_ERROR;
- }
- dmp = m;
- wptr = mtod(dmp, u_char *);
- }
-
- p = (wptr += codelen);
- while (finchar > LAST) {
- dictp = &db->dict[db->dict[finchar].cptr];
- #ifdef DEBUG
- if (--codelen <= 0 || dictp->codem1 != finchar-1)
- goto bad;
- #endif
- *--p = dictp->f.hs.suffix;
- finchar = dictp->f.hs.prefix;
- }
- *--p = finchar;
- #ifdef DEBUG
- if (--codelen != 0)
- printf("bsd_decomp%d: short by %d after code 0x%x, max_ent=0x%x\n",
- db->unit, codelen, incode, max_ent);
- #endif
- if (extra)
- *wptr++ = finchar;
-
- if (oldcode != CLEAR && max_ent < db->maxmaxcode) {
- struct bsd_dict *dictp2;
- u_int32_t fcode;
- u_int32_t hval, disp;
- fcode = BSD_KEY(oldcode,finchar);
- hval = BSD_HASH(oldcode,finchar,db->hshift);
- dictp = &db->dict[hval];
-
- if (dictp->codem1 < max_ent) {
- disp = (hval == 0) ? 1 : hval;
- do {
- hval += disp;
- if (hval >= db->hsize)
- hval -= db->hsize;
- dictp = &db->dict[hval];
- } while (dictp->codem1 < max_ent);
- }
-
- dictp2 = &db->dict[max_ent+1];
- if (db->dict[dictp2->cptr].codem1 == max_ent) {
- db->dict[dictp2->cptr].codem1 = BADCODEM1;
- }
- dictp2->cptr = hval;
- dictp->codem1 = max_ent;
- dictp->f.fcode = fcode;
- db->max_ent = ++max_ent;
- db->lens[max_ent] = db->lens[oldcode]+1;
-
- if (max_ent >= MAXCODE(n_bits) && max_ent < db->maxmaxcode) {
- db->n_bits = ++n_bits;
- tgtbitno = 32-n_bits;
- }
- }
- oldcode = incode;
- }
- dmp->m_len = wptr - mtod(dmp, u_char *);
-
- db->bytes_out += ilen;
- db->in_count += explen;
- if (bsd_check(db) && db->debug) {
- printf("bsd_decomp%d: peer should have cleared dictionary\n",
- db->unit);
- }
- ++db->comp_count;
- db->comp_bytes += ilen + BSD_OVHD;
- ++db->uncomp_count;
- db->uncomp_bytes += explen;
- *dmpp = mret;
- return DECOMP_OK;
- #ifdef DEBUG
- bad:
- if (codelen <= 0) {
- printf("bsd_decomp%d: fell off end of chain ", db->unit);
- printf("0x%x at 0x%x by 0x%x, max_ent=0x%x\n",
- incode, finchar, db->dict[finchar].cptr, max_ent);
- } else if (dictp->codem1 != finchar-1) {
- printf("bsd_decomp%d: bad code chain 0x%x finchar=0x%x ",
- db->unit, incode, finchar);
- printf("oldcode=0x%x cptr=0x%x codem1=0x%x\n", oldcode,
- db->dict[finchar].cptr, dictp->codem1);
- }
- m_freem(mret);
- return DECOMP_FATALERROR;
- #endif
- }
- #endif
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