gpxe/src/util/nrv2b.c

   1 /**************************************************************
   2     Form adapted from lzhuf.c
   3     written by Haruyasu Yoshizaki 11/20/1988
   4     some minor changes 4/6/1989
   5     comments translated by Haruhiko Okumura 4/7/1989
   6
   7     minor beautifications and adjustments for compiling under Linux
   8     by Markus Gutschke <gutschk@math.uni-muenster.de>
   9                                                 1997-01-27
  10
  11     Modifications to allow use as a filter by Ken Yap
  12     <ken_yap@users.sourceforge.net>.
  13
  14                                                 1997-07-01
  15
  16     Small mod to cope with running on big-endian machines
  17     by Jim Hague <jim.hague@acm.org)
  18                                                 1998-02-06
  19
  20     Make compression statistics report shorter
  21     by Ken Yap <ken_yap@users.sourceforge.net>.
  22                                                 2001-04-25
  23
  24     Replaced algorithm with nrv2b from ucl the compression
  25     library from upx.  That code is:
  26     Copyright (C) 1996-2002 Markus Franz Xaver Johannes Oberhumer
  27     And is distributed under the terms of the GPL.
  28     The conversion was performed
  29     by Eric Biederman <ebiederman@lnxi.com>.
  30                                              20 August 2002
  31
  32 **************************************************************/
  33 #define UCLPACK_COMPAT 0
  34 #define NDEBUG 1
  35 #include <stdio.h>
  36 #include <stdlib.h>
  37 #include <string.h>
  38 #include <ctype.h>
  39 #include <errno.h>
  40 #ifdef __FreeBSD__
  41 #include <inttypes.h>
  42 #else
  43 #include <stdint.h>
  44 #endif
  45 #include <limits.h>
  46 #include <assert.h>
  47 #if UCLPACK_COMPAT
  48 #include <netinet/in.h>
  49 #endif
  50
  51 #ifndef VERBOSE
  52 #define Fprintf(x)
  53 #define wterr     0
  54 #else
  55 #define Fprintf(x) fprintf x
  56 #endif
  57
  58 #ifndef MAIN
  59 extern
  60 #endif
  61 FILE  *infile, *outfile;
  62
  63 #if defined(ENCODE) || defined(DECODE)
  64
  65 #ifndef ENDIAN
  66 #define ENDIAN   0
  67 #endif
  68 #ifndef BITSIZE
  69 #define BITSIZE 32
  70 #endif
  71
  72 static __inline__ void Error(char *message)
  73 {
  74         Fprintf((stderr, "\n%s\n", message));
  75         exit(EXIT_FAILURE);
  76 }
  77
  78 /* These will be a complete waste of time on a lo-endian */
  79 /* system, but it only gets done once so WTF. */
  80 static unsigned long i86ul_to_host(unsigned long ul)
  81 {
  82         unsigned long res = 0;
  83         int i;
  84         union
  85         {
  86                 unsigned char c[4];
  87                 unsigned long ul;
  88         } u;
  89
  90         u.ul = ul;
  91         for (i = 3; i >= 0; i--)
  92                 res = (res << 8) + u.c[i];
  93         return res;
  94 }
  95
  96 static unsigned long host_to_i86ul(unsigned long ul)
  97 {
  98         int i;
  99         union
 100         {
 101                 unsigned char c[4];
 102                 unsigned long ul;
 103         } u;
 104
 105         for (i = 0; i < 4; i++)
 106         {
 107                 u.c[i] = ul & 0xff;
 108                 ul >>= 8;
 109         }
 110         return u.ul;
 111 }
 112 #endif
 113
 114
 115
 116 #if UCLPACK_COMPAT
 117 /* magic file header for compressed files */
 118 static const unsigned char magic[8] =
 119 { 0x00, 0xe9, 0x55, 0x43, 0x4c, 0xff, 0x01, 0x1a };
 120
 121 #endif
 122
 123 #ifdef ENCODE
 124 /********** NRV2B_99 compression **********/
 125
 126 /* Note by limiting the ring buffer I have limited the maximum
 127  * offset to 64K.  Since etherboot rarely gets that big it
 128  * is not a problem and it gives me a firm guarantee
 129  * that I will never get a 3 byte string match that is encodes
 130  * to more than 9/8 it's original size.
 131  * That guaranteee is important to for the inplace decompressor.
 132  * There are better ways to do this if a larger offset and buffer
 133  * would give better compression.
 134  */
 135 #define N       (65536ul)           /* size of ring buffer */
 136 #define THRESHOLD       1           /* lower limit for match length */
 137 #define F            2048           /* upper limit for match length */
 138 #define M2_MAX_OFFSET                 0xd00
 139
 140 /* note: to use default values pass -1, i.e. initialize
 141  * this struct by a memset(x,0xff,sizeof(x)) */
 142 struct ucl_compress_config
 143 {
 144         int bb_endian;
 145         int bb_size;
 146         unsigned int max_offset;
 147         unsigned int max_match;
 148         int s_level;
 149         int h_level;
 150         int p_level;
 151         int c_flags;
 152         unsigned int m_size;
 153 };
 154
 155 struct ucl_compress
 156 {
 157         int init;
 158
 159         unsigned int look;          /* bytes in lookahead buffer */
 160
 161         unsigned int m_len;
 162         unsigned int m_off;
 163
 164         unsigned int last_m_len;
 165         unsigned int last_m_off;
 166
 167         const unsigned char *bp;
 168         const unsigned char *ip;
 169         const unsigned char *in;
 170         const unsigned char *in_end;
 171         unsigned char *out;
 172
 173         uint64_t bb_b;
 174         unsigned bb_k;
 175         unsigned bb_c_endian;
 176         unsigned bb_c_s;
 177         unsigned bb_c_s8;
 178         unsigned char *bb_p;
 179         unsigned char *bb_op;
 180
 181         struct ucl_compress_config conf;
 182         unsigned int *result;
 183
 184         unsigned int textsize;      /* text size counter */
 185         unsigned int codesize;      /* code size counter */
 186         unsigned int printcount; /* counter for reporting progress every 1K
 187                                     bytes */
 188
 189
 190         /* some stats */
 191         unsigned long lit_bytes;
 192         unsigned long match_bytes;
 193         unsigned long rep_bytes;
 194         unsigned long lazy;
 195 };
 196
 197
 198
 199 #define getbyte(c)  ((c).ip < (c).in_end ? *((c).ip)++ : (-1))
 200
 201 #define UCL_E_OK               0
 202 #define UCL_E_INVALID_ARGUMENT 1
 203 #define UCL_E_OUT_OF_MEMORY    2
 204 #define UCL_E_ERROR            3
 205
 206 /***********************************************************************
 207 //
 208 ************************************************************************/
 209
 210 #define SWD_HSIZE       16384
 211 #define SWD_MAX_CHAIN   2048
 212 #define SWD_BEST_OFF    1
 213
 214 #define HEAD3(b,p) \
 215     (((0x9f5f*(((((uint32_t)b[p]<<5)^b[p+1])<<5)^b[p+2]))>>5) & (SWD_HSIZE-1))
 216
 217 #define HEAD2(b,p)      (b[p] ^ ((unsigned)b[p+1]<<8))
 218 #define NIL2              UINT_MAX
 219
 220 struct ucl_swd
 221 {
 222 /* public - "built-in" */
 223         unsigned int n;
 224         unsigned int f;
 225         unsigned int threshold;
 226
 227 /* public - configuration */
 228         unsigned int max_chain;
 229         unsigned int nice_length;
 230         int use_best_off;
 231         unsigned int lazy_insert;
 232
 233 /* public - output */
 234         unsigned int m_len;
 235         unsigned int m_off;
 236         unsigned int look;
 237         int b_char;
 238 #if defined(SWD_BEST_OFF)
 239         unsigned int best_off[ SWD_BEST_OFF ];
 240 #endif
 241
 242 /* semi public */
 243         struct ucl_compress *c;
 244         unsigned int m_pos;
 245 #if defined(SWD_BEST_OFF)
 246         unsigned int best_pos[ SWD_BEST_OFF ];
 247 #endif
 248
 249 /* private */
 250         const uint8_t *dict;
 251         const uint8_t *dict_end;
 252         unsigned int dict_len;
 253
 254 /* private */
 255         unsigned int ip;                /* input pointer (lookahead) */
 256         unsigned int bp;                /* buffer pointer */
 257         unsigned int rp;                /* remove pointer */
 258         unsigned int b_size;
 259
 260         unsigned char *b_wrap;
 261
 262         unsigned int node_count;
 263         unsigned int first_rp;
 264
 265         unsigned char b [ N + F + F ];
 266         unsigned int head3 [ SWD_HSIZE ];
 267         unsigned int succ3 [ N + F ];
 268         unsigned int best3 [ N + F ];
 269         unsigned int llen3 [ SWD_HSIZE ];
 270         unsigned int head2 [ 65536U ];
 271 };
 272
 273 #define s_head3(s,key)        s->head3[key]
 274
 275
 276 #if !defined( NDEBUG)
 277 static void assert_match(const struct ucl_swd * swd, unsigned int m_len,
 278         unsigned int m_off )
 279
 280 {
 281         const struct ucl_compress *c = swd->c;
 282         unsigned int d_off;
 283
 284         assert(m_len >= 2);
 285         if (m_off <= (unsigned int) (c->bp - c->in))
 286         {
 287                 assert(c->bp - m_off + m_len < c->ip);
 288                 assert(memcmp(c->bp, c->bp - m_off, m_len) == 0);
 289         }
 290         else
 291         {
 292                 assert(swd->dict != NULL);
 293                 d_off = m_off - (unsigned int) (c->bp - c->in);
 294                 assert(d_off <= swd->dict_len);
 295                 if (m_len > d_off)
 296                 {
 297                         assert(memcmp(c->bp, swd->dict_end - d_off, d_off) ==
 298                                 0);
 299
 300                         assert(c->in + m_len - d_off < c->ip);
 301                         assert(memcmp(c->bp + d_off, c->in, m_len - d_off) ==
 302                                 0);
 303
 304                 }
 305                 else
 306                 {
 307                         assert(memcmp(c->bp, swd->dict_end - d_off, m_len) ==
 308                                 0);
 309
 310                 }
 311         }
 312 }
 313 #else
 314 #  define assert_match(a,b,c)   ((void)0)
 315 #endif
 316
 317 /***********************************************************************
 318 //
 319 ************************************************************************/
 320
 321
 322 static
 323 void swd_initdict(struct ucl_swd *s, const uint8_t *dict, unsigned int dict_len)
 324
 325 {
 326         s->dict = s->dict_end = NULL;
 327         s->dict_len = 0;
 328
 329         if (!dict || dict_len <= 0)
 330                 return;
 331         if (dict_len > s->n)
 332         {
 333                 dict += dict_len - s->n;
 334                 dict_len = s->n;
 335         }
 336
 337         s->dict = dict;
 338         s->dict_len = dict_len;
 339         s->dict_end = dict + dict_len;
 340         memcpy(s->b,dict,dict_len);
 341         s->ip = dict_len;
 342 }
 343
 344
 345 static
 346 void swd_insertdict(struct ucl_swd *s, unsigned int node, unsigned int len)
 347 {
 348         unsigned int key;
 349
 350         s->node_count = s->n - len;
 351         s->first_rp = node;
 352
 353         while (len-- > 0)
 354         {
 355                 key = HEAD3(s->b,node);
 356                 s->succ3[node] = s_head3(s,key);
 357                 s->head3[key] = (unsigned int)(node);
 358                 s->best3[node] = (unsigned int)(s->f + 1);
 359                 s->llen3[key]++;
 360                 assert(s->llen3[key] <= s->n);
 361
 362                 key = HEAD2(s->b,node);
 363                 s->head2[key] = (unsigned int)(node);
 364
 365                 node++;
 366         }
 367 }
 368
 369 /***********************************************************************
 370 //
 371 ************************************************************************/
 372
 373
 374 static
 375 int swd_init(struct ucl_swd *s, const uint8_t *dict, unsigned int dict_len)
 376 {
 377         unsigned int i = 0;
 378         int c = 0;
 379
 380         if (s->n == 0)
 381                 s->n = N;
 382         if (s->f == 0)
 383                 s->f = F;
 384         s->threshold = THRESHOLD;
 385         if (s->n > N || s->f > F)
 386                 return UCL_E_INVALID_ARGUMENT;
 387
 388         /* defaults */
 389         s->max_chain = SWD_MAX_CHAIN;
 390         s->nice_length = s->f;
 391         s->use_best_off = 0;
 392         s->lazy_insert = 0;
 393
 394         s->b_size = s->n + s->f;
 395         if (s->b_size + s->f >= UINT_MAX)
 396                 return UCL_E_ERROR;
 397         s->b_wrap = s->b + s->b_size;
 398         s->node_count = s->n;
 399
 400         memset(s->llen3, 0, sizeof(s->llen3[0]) * SWD_HSIZE);
 401         for (i = 0; i < 65536U; i++)
 402                 s->head2[i] = NIL2;
 403
 404         s->ip = 0;
 405         swd_initdict(s,dict,dict_len);
 406         s->bp = s->ip;
 407         s->first_rp = s->ip;
 408
 409         assert(s->ip + s->f <= s->b_size);
 410
 411         s->look = (unsigned int) (s->c->in_end - s->c->ip);
 412         if (s->look > 0)
 413         {
 414                 if (s->look > s->f)
 415                         s->look = s->f;
 416                 memcpy(&s->b[s->ip],s->c->ip,s->look);
 417                 s->c->ip += s->look;
 418                 s->ip += s->look;
 419         }
 420         if (s->ip == s->b_size)
 421                 s->ip = 0;
 422
 423         if (s->look >= 2 && s->dict_len > 0)
 424                 swd_insertdict(s,0,s->dict_len);
 425
 426         s->rp = s->first_rp;
 427         if (s->rp >= s->node_count)
 428                 s->rp -= s->node_count;
 429         else
 430                 s->rp += s->b_size - s->node_count;
 431
 432         /* unused i */
 433         /* unused c */
 434         return UCL_E_OK;
 435 }
 436
 437
 438 static
 439 void swd_exit(struct ucl_swd *s)
 440 {
 441         /* unused s */
 442
 443 }
 444
 445 #define swd_pos2off(s,pos) \
 446         (s->bp > (pos) ? s->bp - (pos) : s->b_size - ((pos) - s->bp))
 447
 448 /***********************************************************************
 449 //
 450 ************************************************************************/
 451
 452 static __inline__
 453 void swd_getbyte(struct ucl_swd *s)
 454 {
 455         int c;
 456
 457         if ((c = getbyte(*(s->c))) < 0)
 458         {
 459                 if (s->look > 0)
 460                         --s->look;
 461         }
 462         else
 463         {
 464                 s->b[s->ip] = (uint8_t)(c);
 465                 if (s->ip < s->f)
 466                         s->b_wrap[s->ip] = (uint8_t)(c);
 467         }
 468         if (++s->ip == s->b_size)
 469                 s->ip = 0;
 470         if (++s->bp == s->b_size)
 471                 s->bp = 0;
 472         if (++s->rp == s->b_size)
 473                 s->rp = 0;
 474 }
 475 /***********************************************************************
 476 // remove node from lists
 477 ************************************************************************/
 478
 479 static __inline__
 480 void swd_remove_node(struct ucl_swd *s, unsigned int node)
 481 {
 482         if (s->node_count == 0)
 483         {
 484                 unsigned int key;
 485
 486 #ifdef UCL_DEBUG
 487                 if (s->first_rp != UINT_MAX)
 488                 {
 489                         if (node != s->first_rp)
 490                                 printf("Remove %5d: %5d %5d %5d %5d %6d %6d\n",
 491
 492                                         node, s->rp, s->ip, s->bp, s->first_rp,
 493                                         s->ip - node, s->ip - s->bp);
 494                         assert(node == s->first_rp);
 495                         s->first_rp = UINT_MAX;
 496                 }
 497 #endif
 498
 499                 key = HEAD3(s->b,node);
 500                 assert(s->llen3[key] > 0);
 501                 --s->llen3[key];
 502
 503                 key = HEAD2(s->b,node);
 504                 assert(s->head2[key] != NIL2);
 505                 if ((unsigned int) s->head2[key] == node)
 506                         s->head2[key] = NIL2;
 507         }
 508         else
 509                 --s->node_count;
 510 }
 511
 512
 513 /***********************************************************************
 514 //
 515 ************************************************************************/
 516
 517
 518 static
 519 void swd_accept(struct ucl_swd *s, unsigned int n)
 520 {
 521         assert(n <= s->look);
 522
 523         if (n > 0) do
 524         {
 525                 unsigned int key;
 526
 527                 swd_remove_node(s,s->rp);
 528
 529                 /* add bp into HEAD3 */
 530                 key = HEAD3(s->b,s->bp);
 531                 s->succ3[s->bp] = s_head3(s,key);
 532                 s->head3[key] = (unsigned int)(s->bp);
 533                 s->best3[s->bp] = (unsigned int)(s->f + 1);
 534                 s->llen3[key]++;
 535                 assert(s->llen3[key] <= s->n);
 536
 537                 /* add bp into HEAD2 */
 538                 key = HEAD2(s->b,s->bp);
 539                 s->head2[key] = (unsigned int)(s->bp);
 540
 541                 swd_getbyte(s);
 542         } while (--n > 0);
 543 }
 544
 545 /***********************************************************************
 546 //
 547 ************************************************************************/
 548
 549 static
 550 void swd_search(struct ucl_swd *s, unsigned int node, unsigned int cnt)
 551 {
 552         const unsigned char *p1;
 553         const unsigned char *p2;
 554         const unsigned char *px;
 555
 556         unsigned int m_len = s->m_len;
 557         const unsigned char * b  = s->b;
 558         const unsigned char * bp = s->b + s->bp;
 559         const unsigned char * bx = s->b + s->bp + s->look;
 560         unsigned char scan_end1;
 561
 562         assert(s->m_len > 0);
 563
 564         scan_end1 = bp[m_len - 1];
 565         for ( ; cnt-- > 0; node = s->succ3[node])
 566         {
 567                 p1 = bp;
 568                 p2 = b + node;
 569                 px = bx;
 570
 571                 assert(m_len < s->look);
 572
 573                 if (
 574                         p2[m_len - 1] == scan_end1 &&
 575                         p2[m_len] == p1[m_len] &&
 576                         p2[0] == p1[0] &&
 577                         p2[1] == p1[1])
 578                 {
 579                         unsigned int i;
 580                         assert(memcmp(bp,&b[node],3) == 0);
 581
 582                         p1 += 2; p2 += 2;
 583                         do {} while (++p1 < px && *p1 == *++p2);
 584                         i = p1 - bp;
 585
 586 #ifdef UCL_DEBUG
 587                         if (memcmp(bp,&b[node],i) != 0)
 588                                 printf("%5ld %5ld %02x%02x %02x%02x\n",
 589                                         (long)s->bp, (long) node,
 590                                         bp[0], bp[1], b[node], b[node+1]);
 591 #endif
 592                         assert(memcmp(bp,&b[node],i) == 0);
 593
 594 #if defined(SWD_BEST_OFF)
 595                         if (i < SWD_BEST_OFF)
 596                         {
 597                                 if (s->best_pos[i] == 0)
 598                                         s->best_pos[i] = node + 1;
 599                         }
 600 #endif
 601                         if (i > m_len)
 602                         {
 603                                 s->m_len = m_len = i;
 604                                 s->m_pos = node;
 605                                 if (m_len == s->look)
 606                                         return;
 607                                 if (m_len >= s->nice_length)
 608                                         return;
 609                                 if (m_len > (unsigned int) s->best3[node])
 610                                         return;
 611                                 scan_end1 = bp[m_len - 1];
 612                         }
 613                 }
 614         }
 615 }
 616
 617 static int swd_search2(struct ucl_swd *s)
 618 {
 619         unsigned int key;
 620
 621         assert(s->look >= 2);
 622         assert(s->m_len > 0);
 623
 624         key = s->head2[ HEAD2(s->b,s->bp) ];
 625         if (key == NIL2)
 626                 return 0;
 627 #ifdef UCL_DEBUG
 628         if (memcmp(&s->b[s->bp],&s->b[key],2) != 0)
 629                 printf("%5ld %5ld %02x%02x %02x%02x\n", (long)s->bp, (long)key,
 630                         s->b[s->bp], s->b[s->bp+1], s->b[key], s->b[key+1]);
 631 #endif
 632         assert(memcmp(&s->b[s->bp],&s->b[key],2) == 0);
 633 #if defined(SWD_BEST_OFF)
 634         if (s->best_pos[2] == 0)
 635                 s->best_pos[2] = key + 1;
 636 #endif
 637
 638         if (s->m_len < 2)
 639         {
 640                 s->m_len = 2;
 641                 s->m_pos = key;
 642         }
 643         return 1;
 644 }
 645
 646 /***********************************************************************
 647 //
 648 ************************************************************************/
 649
 650 static
 651 void swd_findbest(struct ucl_swd *s)
 652 {
 653         unsigned int key;
 654         unsigned int cnt, node;
 655         unsigned int len;
 656
 657         assert(s->m_len > 0);
 658
 659         /* get current head, add bp into HEAD3 */
 660         key = HEAD3(s->b,s->bp);
 661         node = s->succ3[s->bp] = s_head3(s,key);
 662         cnt = s->llen3[key]++;
 663         assert(s->llen3[key] <= s->n + s->f);
 664         if (cnt > s->max_chain && s->max_chain > 0)
 665                 cnt = s->max_chain;
 666         s->head3[key] = (unsigned int)(s->bp);
 667
 668         s->b_char = s->b[s->bp];
 669         len = s->m_len;
 670         if (s->m_len >= s->look)
 671         {
 672                 if (s->look == 0)
 673                         s->b_char = -1;
 674                 s->m_off = 0;
 675                 s->best3[s->bp] = (unsigned int)(s->f + 1);
 676         }
 677         else
 678         {
 679                 if (swd_search2(s))
 680                         if (s->look >= 3)
 681                                 swd_search(s,node,cnt);
 682                 if (s->m_len > len)
 683                         s->m_off = swd_pos2off(s,s->m_pos);
 684                 s->best3[s->bp] = (unsigned int)(s->m_len);
 685
 686 #if defined(SWD_BEST_OFF)
 687                 if (s->use_best_off)
 688                 {
 689                         int i;
 690                         for (i = 2; i < SWD_BEST_OFF; i++)
 691                                 if (s->best_pos[i] > 0)
 692                                         s->best_off[i] =
 693                                                 swd_pos2off(s,s->best_pos[i]-1);
 694
 695                                 else
 696                                         s->best_off[i] = 0;
 697                 }
 698 #endif
 699         }
 700
 701         swd_remove_node(s,s->rp);
 702
 703         /* add bp into HEAD2 */
 704         key = HEAD2(s->b,s->bp);
 705         s->head2[key] = (unsigned int)(s->bp);
 706 }
 707
 708
 709 /***********************************************************************
 710 //
 711 ************************************************************************/
 712
 713 static int
 714 init_match ( struct ucl_compress *c, struct ucl_swd *s,
 715         const uint8_t *dict, unsigned int dict_len,
 716         uint32_t flags )
 717 {
 718         int r;
 719
 720         assert(!c->init);
 721         c->init = 1;
 722
 723         s->c = c;
 724
 725         c->last_m_len = c->last_m_off = 0;
 726
 727         c->textsize = c->codesize = c->printcount = 0;
 728         c->lit_bytes = c->match_bytes = c->rep_bytes = 0;
 729         c->lazy = 0;
 730
 731         r = swd_init(s,dict,dict_len);
 732         if (r != UCL_E_OK)
 733         {
 734                 swd_exit(s);
 735                 return r;
 736         }
 737
 738         s->use_best_off = (flags & 1) ? 1 : 0;
 739         return UCL_E_OK;
 740 }
 741
 742 static int
 743 find_match ( struct ucl_compress *c, struct ucl_swd *s,
 744         unsigned int this_len, unsigned int skip )
 745 {
 746         assert(c->init);
 747
 748         if (skip > 0)
 749         {
 750                 assert(this_len >= skip);
 751                 swd_accept(s, this_len - skip);
 752                 c->textsize += this_len - skip + 1;
 753         }
 754         else
 755         {
 756                 assert(this_len <= 1);
 757                 c->textsize += this_len - skip;
 758         }
 759
 760         s->m_len = THRESHOLD;
 761 #ifdef SWD_BEST_OFF
 762         if (s->use_best_off)
 763                 memset(s->best_pos,0,sizeof(s->best_pos));
 764 #endif
 765         swd_findbest(s);
 766         c->m_len = s->m_len;
 767         c->m_off = s->m_off;
 768
 769         swd_getbyte(s);
 770
 771         if (s->b_char < 0)
 772         {
 773                 c->look = 0;
 774                 c->m_len = 0;
 775                 swd_exit(s);
 776         }
 777         else
 778         {
 779                 c->look = s->look + 1;
 780         }
 781         c->bp = c->ip - c->look;
 782
 783 #if 0
 784         /* brute force match search */
 785         if (c->m_len > THRESHOLD && c->m_len + 1 <= c->look)
 786         {
 787                 const uint8_t *ip = c->bp;
 788                 const uint8_t *m  = c->bp - c->m_off;
 789                 const uint8_t *in = c->in;
 790
 791                 if (ip - in > N)
 792                         in = ip - N;
 793                 for (;;)
 794                 {
 795                         while (*in != *ip)
 796                                 in++;
 797                         if (in == ip)
 798                                 break;
 799                         if (in != m)
 800                                 if (memcmp(in,ip,c->m_len+1) == 0)
 801                                         printf("%p %p %p %5d\n",in,ip,m,c->m_len);
 802
 803                         in++;
 804                 }
 805         }
 806 #endif
 807
 808         return UCL_E_OK;
 809 }
 810
 811
 812 static int bbConfig(struct ucl_compress *c, int endian, int bitsize)
 813 {
 814         if (endian != -1)
 815         {
 816                 if (endian != 0)
 817                         return UCL_E_ERROR;
 818                 c->bb_c_endian = endian;
 819         }
 820         if (bitsize != -1)
 821         {
 822                 if (bitsize != 8 && bitsize != 16 && bitsize != 32 && bitsize != 64)
 823                         return UCL_E_ERROR;
 824                 c->bb_c_s = bitsize;
 825                 c->bb_c_s8 = bitsize / 8;
 826         }
 827         c->bb_b = 0; c->bb_k = 0;
 828         c->bb_p = NULL;
 829         c->bb_op = NULL;
 830         return UCL_E_OK;
 831 }
 832
 833 static void bbWriteBits(struct ucl_compress *c)
 834 {
 835         uint8_t *p = c->bb_p;
 836         uint64_t b = c->bb_b;
 837
 838         p[0] = (uint8_t)(b >>  0);
 839         if (c->bb_c_s >= 16)
 840         {
 841                 p[1] = (uint8_t)(b >>  8);
 842                 if (c->bb_c_s >= 32)
 843                 {
 844                         p[2] = (uint8_t)(b >> 16);
 845                         p[3] = (uint8_t)(b >> 24);
 846                         if (c->bb_c_s == 64)
 847                         {
 848                                 p[4] = (uint8_t)(b >> 32);
 849                                 p[5] = (uint8_t)(b >> 40);
 850                                 p[6] = (uint8_t)(b >> 48);
 851                                 p[7] = (uint8_t)(b >> 56);
 852                         }
 853                 }
 854         }
 855 }
 856
 857
 858 static void bbPutBit(struct ucl_compress *c, unsigned bit)
 859 {
 860         assert(bit == 0 || bit == 1);
 861         assert(c->bb_k <= c->bb_c_s);
 862
 863         if (c->bb_k < c->bb_c_s)
 864         {
 865                 if (c->bb_k == 0)
 866                 {
 867                         assert(c->bb_p == NULL);
 868                         c->bb_p = c->bb_op;
 869                         c->bb_op += c->bb_c_s8;
 870                 }
 871                 assert(c->bb_p != NULL);
 872                 assert(c->bb_p + c->bb_c_s8 <= c->bb_op);
 873
 874                 c->bb_b = (c->bb_b << 1) + bit;
 875                 c->bb_k++;
 876         }
 877         else
 878         {
 879                 assert(c->bb_p != NULL);
 880                 assert(c->bb_p + c->bb_c_s8 <= c->bb_op);
 881
 882                 bbWriteBits(c);
 883                 c->bb_p = c->bb_op;
 884                 c->bb_op += c->bb_c_s8;
 885                 c->bb_b = bit;
 886                 c->bb_k = 1;
 887         }
 888 }
 889
 890
 891 static void bbPutByte(struct ucl_compress *c, unsigned b)
 892 {
 893         /**printf("putbyte %p %p %x  (%d)\n", op, bb_p, x, bb_k);*/
 894         assert(c->bb_p == NULL || c->bb_p + c->bb_c_s8 <= c->bb_op);
 895         *c->bb_op++ = (uint8_t)(b);
 896 }
 897
 898 static void bbFlushBits(struct ucl_compress *c, unsigned filler_bit)
 899 {
 900         if (c->bb_k > 0)
 901         {
 902                 assert(c->bb_k <= c->bb_c_s);
 903                 while (c->bb_k != c->bb_c_s)
 904                         bbPutBit(c, filler_bit);
 905                 bbWriteBits(c);
 906                 c->bb_k = 0;
 907         }
 908         c->bb_p = NULL;
 909 }
 910
 911
 912
 913 /***********************************************************************
 914 //
 915 ************************************************************************/
 916
 917
 918 static void code_prefix_ss11(struct ucl_compress *c, uint32_t i)
 919 {
 920         if (i >= 2)
 921         {
 922                 uint32_t t = 4;
 923                 i += 2;
 924                 do {
 925                         t <<= 1;
 926                 } while (i >= t);
 927                 t >>= 1;
 928                 do {
 929                         t >>= 1;
 930                         bbPutBit(c, (i & t) ? 1 : 0);
 931                         bbPutBit(c, 0);
 932                 } while (t > 2);
 933         }
 934         bbPutBit(c, (unsigned)i & 1);
 935         bbPutBit(c, 1);
 936 }
 937
 938 static void
 939 code_match(struct ucl_compress *c, unsigned int m_len, const unsigned int m_off)
 940
 941 {
 942         while (m_len > c->conf.max_match)
 943         {
 944                 code_match(c, c->conf.max_match - 3, m_off);
 945                 m_len -= c->conf.max_match - 3;
 946         }
 947
 948         c->match_bytes += m_len;
 949         if (m_len > c->result[3])
 950                 c->result[3] = m_len;
 951         if (m_off > c->result[1])
 952                 c->result[1] = m_off;
 953
 954         bbPutBit(c, 0);
 955
 956         if (m_off == c->last_m_off)
 957         {
 958                 bbPutBit(c, 0);
 959                 bbPutBit(c, 1);
 960         }
 961         else
 962         {
 963                 code_prefix_ss11(c, 1 + ((m_off - 1) >> 8));
 964                 bbPutByte(c, (unsigned)m_off - 1);
 965         }
 966         m_len = m_len - 1 - (m_off > M2_MAX_OFFSET);
 967         if (m_len >= 4)
 968         {
 969                 bbPutBit(c,0);
 970                 bbPutBit(c,0);
 971                 code_prefix_ss11(c, m_len - 4);
 972         }
 973         else
 974         {
 975                 bbPutBit(c, m_len > 1);
 976                 bbPutBit(c, (unsigned)m_len & 1);
 977         }
 978
 979         c->last_m_off = m_off;
 980 }
 981
 982 static void
 983 code_run(struct ucl_compress *c, const uint8_t *ii, unsigned int lit)
 984 {
 985         if (lit == 0)
 986                 return;
 987         c->lit_bytes += lit;
 988         if (lit > c->result[5])
 989                 c->result[5] = lit;
 990         do {
 991                 bbPutBit(c, 1);
 992                 bbPutByte(c, *ii++);
 993         } while (--lit > 0);
 994 }
 995
 996 /***********************************************************************
 997 //
 998 ************************************************************************/
 999
1000 static int
1001 len_of_coded_match(struct ucl_compress *c, unsigned int m_len, unsigned int
1002         m_off)
1003
1004 {
1005         int b;
1006         if (m_len < 2 || (m_len == 2 && (m_off > M2_MAX_OFFSET))
1007                 || m_off > c->conf.max_offset)
1008                 return -1;
1009         assert(m_off > 0);
1010
1011         m_len = m_len - 2 - (m_off > M2_MAX_OFFSET);
1012
1013         if (m_off == c->last_m_off)
1014                 b = 1 + 2;
1015         else
1016         {
1017                 b = 1 + 10;
1018                 m_off = (m_off - 1) >> 8;
1019                 while (m_off > 0)
1020                 {
1021                         b += 2;
1022                         m_off >>= 1;
1023                 }
1024         }
1025
1026         b += 2;
1027         if (m_len < 3)
1028                 return b;
1029         m_len -= 3;
1030
1031         do {
1032                 b += 2;
1033                 m_len >>= 1;
1034         } while (m_len > 0);
1035
1036         return b;
1037 }
1038
1039 int ucl_nrv2b_99_compress(
1040         const uint8_t *in, unsigned long in_len,
1041         uint8_t *out, unsigned long *out_len,
1042         unsigned int *result)
1043 {
1044         const uint8_t *ii;
1045         unsigned int lit;
1046         unsigned int m_len, m_off;
1047         struct ucl_compress c_buffer;
1048         struct ucl_compress * const c = &c_buffer;
1049         struct ucl_swd *swd;
1050         unsigned int result_buffer[16];
1051         int r;
1052
1053 /* max compression */
1054 #define SC_TRY_LAZY    2
1055 #define SC_GOOD_LENGTH F
1056 #define SC_MAX_LAZY    F
1057 #define SC_NICE_LENGTH F
1058 #define SC_MAX_CHAIN   4096
1059 #define SC_FLAGS       1
1060 #define SC_MAX_OFFSET  N
1061
1062         memset(c, 0, sizeof(*c));
1063         c->ip = c->in = in;
1064         c->in_end = in + in_len;
1065         c->out = out;
1066         c->result = result ? result : result_buffer;
1067         memset(c->result, 0, 16*sizeof(*c->result));
1068         c->result[0] = c->result[2] = c->result[4] = UINT_MAX;
1069         result = NULL;
1070         memset(&c->conf, 0xff, sizeof(c->conf));
1071         r = bbConfig(c, ENDIAN, BITSIZE);
1072         if (r == 0)
1073                 r = bbConfig(c, c->conf.bb_endian, c->conf.bb_size);
1074         if (r != 0)
1075                 return UCL_E_INVALID_ARGUMENT;
1076         c->bb_op = out;
1077
1078         ii = c->ip;             /* point to start of literal run */
1079         lit = 0;
1080
1081
1082         swd = (struct ucl_swd *) malloc(sizeof(*swd));
1083         if (!swd)
1084                 return UCL_E_OUT_OF_MEMORY;
1085
1086         swd->f = F;
1087         swd->n = N;
1088         if (in_len >= 256 && in_len < swd->n)
1089                 swd->n = in_len;
1090         if (swd->f < 8 || swd->n < 256)
1091                 return UCL_E_INVALID_ARGUMENT;
1092
1093         r = init_match(c,swd,NULL,0, SC_FLAGS);
1094         if (r != UCL_E_OK)
1095         {
1096                 free(swd);
1097                 return r;
1098         }
1099         if (SC_MAX_CHAIN > 0)
1100                 swd->max_chain = SC_MAX_CHAIN;
1101         if (SC_NICE_LENGTH > 0)
1102                 swd->nice_length = SC_NICE_LENGTH;
1103         if (c->conf.max_match < swd->nice_length)
1104                 swd->nice_length = c->conf.max_match;
1105
1106         c->last_m_off = 1;
1107         r = find_match(c,swd,0,0);
1108         if (r != UCL_E_OK)
1109                 return r;
1110         while (c->look > 0)
1111         {
1112                 unsigned int ahead;
1113                 unsigned int max_ahead;
1114                 int l1, l2;
1115
1116                 c->codesize = c->bb_op - out;
1117
1118                 m_len = c->m_len;
1119                 m_off = c->m_off;
1120
1121                 assert(c->bp == c->ip - c->look);
1122                 assert(c->bp >= in);
1123                 if (lit == 0)
1124                         ii = c->bp;
1125                 assert(ii + lit == c->bp);
1126                 assert(swd->b_char == *(c->bp));
1127
1128                 if (m_len < 2 || (m_len == 2 && (m_off > M2_MAX_OFFSET))
1129                         || m_off > c->conf.max_offset)
1130                 {
1131                         /* a literal */
1132                         lit++;
1133                         swd->max_chain = SC_MAX_CHAIN;
1134                         r = find_match(c,swd,1,0);
1135                         assert(r == 0);
1136                         continue;
1137                 }
1138
1139                 /* a match */
1140                 assert_match(swd,m_len,m_off);
1141
1142                 /* shall we try a lazy match ? */
1143                 ahead = 0;
1144                 if (SC_TRY_LAZY <= 0 || m_len >= SC_MAX_LAZY || m_off ==
1145                         c->last_m_off)
1146
1147                 {
1148                         /* no */
1149                         l1 = 0;
1150                         max_ahead = 0;
1151                 }
1152                 else
1153                 {
1154                         /* yes, try a lazy match */
1155                         l1 = len_of_coded_match(c,m_len,m_off);
1156                         assert(l1 > 0);
1157                         max_ahead = SC_TRY_LAZY;
1158                         if ((m_len - 1) < max_ahead) {
1159                                 max_ahead = m_len -1;
1160                         }
1161                 }
1162
1163                 while (ahead < max_ahead && c->look > m_len)
1164                 {
1165                         if (m_len >= SC_GOOD_LENGTH)
1166                                 swd->max_chain = SC_MAX_CHAIN >> 2;
1167                         else
1168                                 swd->max_chain = SC_MAX_CHAIN;
1169                         r = find_match(c,swd,1,0);
1170                         ahead++;
1171
1172                         assert(r == 0);
1173                         assert(c->look > 0);
1174                         assert(ii + lit + ahead == c->bp);
1175
1176                         if (c->m_len < 2)
1177                                 continue;
1178                         l2 = len_of_coded_match(c,c->m_len,c->m_off);
1179                         if (l2 < 0)
1180                                 continue;
1181                         if (l1 + (int)(ahead + c->m_len - m_len) * 5 > l2 +
1182                                 (int)(ahead) * 9)
1183                         {
1184                                 c->lazy++;
1185                                 assert_match(swd,c->m_len,c->m_off);
1186                                 lit += ahead;
1187                                 assert(ii + lit == c->bp);
1188                                 goto lazy_match_done;
1189                         }
1190                 }
1191
1192                 assert(ii + lit + ahead == c->bp);
1193
1194                 /* 1 - code run */
1195                 code_run(c,ii,lit);
1196                 lit = 0;
1197
1198                 /* 2 - code match */
1199                 code_match(c,m_len,m_off);
1200                 swd->max_chain = SC_MAX_CHAIN;
1201                 r = find_match(c,swd,m_len,1+ahead);
1202                 assert(r == 0);
1203
1204         lazy_match_done: ;
1205         }
1206
1207         /* store final run */
1208         code_run(c,ii,lit);
1209
1210         /* EOF */
1211         bbPutBit(c, 0);
1212         code_prefix_ss11(c, 0x1000000U);
1213         bbPutByte(c, 0xff);
1214
1215         bbFlushBits(c, 0);
1216
1217         assert(c->textsize == in_len);
1218         c->codesize = c->bb_op - out;
1219         *out_len = c->bb_op - out;
1220
1221 #if 0
1222         printf("%7ld %7ld -> %7ld   %7ld %7ld   %ld  (max: %d %d %d)\n",
1223                 (long) c->textsize, (long) in_len, (long) c->codesize,
1224                 c->match_bytes, c->lit_bytes,  c->lazy,
1225                 c->result[1], c->result[3], c->result[5]);
1226 #endif
1227         assert(c->lit_bytes + c->match_bytes == in_len);
1228
1229         swd_exit(swd);
1230         free(swd);
1231
1232         return UCL_E_OK;
1233 }
1234
1235
1236 void Encode(void)  /* compression */
1237 {
1238         uint8_t *in, *out;
1239         unsigned long in_len, out_len;
1240         uint32_t tw;
1241         int r;
1242         fseek(infile, 0, SEEK_END);
1243         in_len = ftell(infile);
1244 #ifdef VERBOSE
1245         if ((signed long)in_len < 0)
1246                 Fprintf((stderr, "Errno: %d", errno));
1247 #endif
1248 #if UCLPACK_COMPAT
1249         {
1250                 uint8_t byte;
1251                 if (fwrite(magic, sizeof(magic), 1, outfile) != 1)
1252                         Error("Can't write.");
1253                 tw = htonl(0); /* flags */
1254                 if (fwrite(&tw, sizeof(tw), 1, outfile) != 1)
1255                         Error("Can't write.");
1256                 byte = 0x2b;            /* method */
1257                 if (fwrite(&byte, sizeof(byte), 1, outfile) != 1)
1258                         Error("Can't write.");
1259                 byte = 10;              /* level */
1260                 if (fwrite(&byte, sizeof(byte), 1, outfile) != 1)
1261                         Error("Can't write.");
1262                 tw = htonl(256*1024);           /* block_size */
1263                 if (fwrite(&tw, sizeof(tw), 1, outfile) != 1)
1264                         Error("Can't write.");
1265                 tw = htonl(in_len);
1266                 if (fwrite(&tw, sizeof(tw), 1, outfile) != 1)
1267                         Error("Can't write.");  /* output size of text */
1268         }
1269 #else
1270         tw = host_to_i86ul(in_len);
1271         if (fwrite(&tw, sizeof(tw), 1, outfile) != 1)
1272                 Error("Can't write.");  /* output size of text */
1273 #endif
1274         if (in_len == 0)
1275                 return;
1276         rewind(infile);
1277
1278         in = malloc(in_len);
1279         out_len = in_len + (in_len/8) + 256;
1280         out = malloc(out_len);
1281         if (!in || !out) {
1282                 Error("Can't malloc");
1283         }
1284         if (fread(in, in_len, 1, infile) != 1) {
1285                 Error("Can't read");
1286         }
1287         r = ucl_nrv2b_99_compress(in, in_len, out, &out_len, 0 );
1288         if (r != UCL_E_OK)
1289                 Error("Compression failure\n");
1290 #if UCLPACK_COMPAT
1291         tw = htonl(out_len);
1292         if (fwrite(&tw, sizeof(tw), 1, outfile) != 1)
1293                 Error("Can't write.");  /* file size of text */
1294
1295 #endif
1296         if (fwrite(out, out_len, 1, outfile) != 1) {
1297                 Error("Write error\n");
1298         }
1299 #if UCLPACK_COMPAT
1300         tw = htonl(0); /* EOF marker */
1301         if (fwrite(&tw, sizeof(tw), 1, outfile) != 1)
1302                 Error("Can't write.");
1303
1304 #endif
1305
1306 #ifdef  LONG_REPORT
1307         Fprintf((stdout, "input size    %ld bytes\n", in_len));
1308         Fprintf((stdout, "output size   %ld bytes\n", out_len));
1309         Fprintf((stdout, "input/output  %.3f\n", (double)in_len / out_len));
1310 #else
1311         Fprintf((stdout, "input/output = %ld/%ld = %.3f\n", in_len, out_len,
1312                 (double)in_len / out_len));
1313 #endif
1314
1315 }
1316
1317 #endif
1318
1319 #ifdef DECODE
1320
1321 #define GETBIT_8(bb, src, ilen) \
1322     (((bb = bb & 0x7f ? bb*2 : ((unsigned)src[ilen++]*2+1)) >> 8) & 1)
1323
1324 #define GETBIT_LE16(bb, src, ilen) \
1325     (bb*=2,bb&0xffff ? (bb>>16)&1 : (ilen+=2,((bb=(src[ilen-2]+src[ilen-1]*256u)*2+1)>>16)&1))
1326
1327 #define GETBIT_LE32(bb, src, ilen) \
1328     (bc > 0 ? ((bb>>--bc)&1) : (bc=31,\
1329     bb=*(const uint32_t *)((src)+ilen),ilen+=4,(bb>>31)&1))
1330
1331 #define GETBIT_LE64(bb, src, ilen) \
1332     (bc > 0 ? ((bb>>--bc)&1) : (bc=63, \
1333     bb=*(const uint64_t *)((src)+ilen),ilen+=8,(bb>>63)&1))
1334
1335 #if ENDIAN == 0 && BITSIZE == 8
1336 #define GETBIT(bb, src, ilen) GETBIT_8(bb, src, ilen)
1337 #endif
1338 #if ENDIAN == 0 && BITSIZE == 16
1339 #define GETBIT(bb, src, ilen) GETBIT_LE16(bb, src, ilen)
1340 #endif
1341 #if ENDIAN == 0 && BITSIZE == 32
1342 #define GETBIT(bb, src, ilen) GETBIT_LE32(bb, src, ilen)
1343 #endif
1344 #if ENDIAN == 0 && BITSIZE == 64
1345 #define GETBIT(bb, src, ilen) GETBIT_LE64(bb, src, ilen)
1346 #endif
1347 #ifndef GETBIT
1348 #error "Bad Combination of ENDIAN and BITSIZE values specified"
1349 #endif
1350
1351 #undef SAFE
1352
1353 #ifdef SAFE
1354 #define FAIL(x,r)   if (x) { Error(r); }
1355 #else
1356 #define FAIL(x,r)
1357 #endif
1358
1359 void Decode(void)  /* recover */
1360 {
1361         uint32_t tw;
1362         uint8_t *src, *dst;
1363         unsigned long max_src_len, src_len, dst_len;
1364         unsigned long ilen = 0, olen = 0, last_m_off =  1;
1365 #if BITSIZE <= 32
1366         uint32_t bb = 0;
1367 #elif BITSIZE == 64
1368         uint64_t bb = 0;
1369 #endif
1370         unsigned bc = 0;
1371 #if UCLPACK_COMPAT
1372         if (fseek(infile, sizeof(magic) + sizeof(tw) + 1 + 1 + sizeof(tw),
1373                 SEEK_SET) != 0)
1374
1375                 Error("Seek Error");
1376         if (fread(&tw, sizeof(tw), 1, infile) < 1)
1377                 Error("Can't read"); /* read size of text */
1378         dst_len = ntohl(tw);
1379         if (fread(&tw, sizeof(tw), 1, infile) < 1)
1380                 Error("Can't read"); /* read size of file */
1381         max_src_len = ntohl(tw);
1382 #else
1383         if (fread(&tw, sizeof(tw), 1, infile) < 1)
1384                 Error("Can't read"); /* read size of text */
1385         dst_len = i86ul_to_host(tw);
1386         max_src_len = dst_len + (dst_len/8) + 256;
1387 #endif
1388         if (dst_len == 0)
1389                 return;
1390         dst = malloc(dst_len);
1391         if (!dst)
1392                 Error("Can't malloc");
1393         src = malloc(max_src_len);
1394         if (!src)
1395                 Error("Can't malloc");
1396         src_len = fread(src, 1, max_src_len, infile);
1397         if (src_len <= 0)
1398                 Error("Can't read");
1399
1400         for(;;) {
1401                 unsigned int m_off, m_len;
1402                 while(GETBIT(bb, src, ilen)) {
1403                         FAIL(ilen >= src_len, "input overrun");
1404                         FAIL(olen >= dst_len, "output  overrun");
1405                         dst[olen++] = src[ilen++];
1406                 }
1407                 m_off = 1;
1408                 do {
1409                         m_off = m_off*2 + GETBIT(bb, src, ilen);
1410                         FAIL(ilen >= src_len, "input overrun");
1411                         FAIL(m_off > 0xffffffU +3, "lookbehind overrun");
1412                 } while (!GETBIT(bb, src, ilen));
1413                 if (m_off == 2)
1414                 {
1415                         m_off = last_m_off;
1416                 }
1417                 else
1418                 {
1419                         FAIL(ilen >= src_len, "input overrun");
1420                         m_off = (m_off - 3)*256 + src[ilen++];
1421                         if (m_off == 0xffffffffU)
1422                                 break;
1423                         last_m_off = ++m_off;
1424                 }
1425                 m_len = GETBIT(bb, src, ilen);
1426                 m_len = m_len*2 + GETBIT(bb, src, ilen);
1427                 if (m_len == 0)
1428                 {
1429                         m_len++;
1430                         do {
1431                                 m_len = m_len*2 + GETBIT(bb, src, ilen);
1432                                 FAIL(ilen >= src_len, "input overrun");
1433                                 FAIL(m_len >= dst_len, "output overrun");
1434                         } while(!GETBIT(bb, src, ilen));
1435                         m_len += 2;
1436                 }
1437                 m_len += (m_off > 0xd00);
1438                 FAIL(olen + m_len > dst_len, "output overrun");
1439                 FAIL(m_off > olen, "lookbeind overrun");
1440                 {
1441                         const uint8_t *m_pos;
1442                         m_pos = dst + olen - m_off;
1443                         dst[olen++] = *m_pos++;
1444                         do {
1445                                 dst[olen++] = *m_pos++;
1446                         } while(--m_len > 0);
1447                 }
1448         }
1449         FAIL(ilen < src_len, "input not consumed");
1450         FAIL(ilen > src_len, "input overrun");
1451         assert(ilen == src_len);
1452         Fprintf((stderr, "%12ld\n", olen));
1453         if (dst_len != olen) {
1454                 fprintf(stderr, "length != expected length\n");
1455         }
1456         if (fwrite(dst, olen, 1, outfile) != 1)
1457                 Error("Write error\n");
1458         free(src);
1459         free(dst);
1460 }
1461 #endif
1462
1463 #ifdef MAIN
1464 int main(int argc, char *argv[])
1465 {
1466         char  *s;
1467         FILE  *f;
1468         int    c;
1469
1470         if (argc == 2) {
1471                 outfile = stdout;
1472                 if ((f = tmpfile()) == NULL) {
1473                         perror("tmpfile");
1474                         return EXIT_FAILURE;
1475                 }
1476                 while ((c = getchar()) != EOF)
1477                         fputc(c, f);
1478                 rewind(infile = f);
1479         }
1480         else if (argc != 4) {
1481                 Fprintf((stderr, "'nrv2b e file1 file2' encodes file1 into file2.\n"
1482                         "'nrv2b d file2 file1' decodes file2 into file1.\n"));
1483                 return EXIT_FAILURE;
1484         }
1485         if (argc == 4) {
1486                 if ((s = argv[1], s[1] || strpbrk(s, "DEde") == NULL)
1487                         || (s = argv[2], (infile  = fopen(s, "rb")) == NULL)
1488                         || (s = argv[3], (outfile = fopen(s, "wb")) == NULL)) {
1489                         Fprintf((stderr, "??? %s\n", s));
1490                         return EXIT_FAILURE;
1491                 }
1492         }
1493         if (toupper(*argv[1]) == 'E')
1494                 Encode();
1495         else
1496                 Decode();
1497         fclose(infile);
1498         fclose(outfile);
1499         return EXIT_SUCCESS;
1500 }
1501 #endif