token.c

   1 /*
   2  * Routines used by the file-transfer code.
   3  *
   4  * Copyright (C) 1996 Andrew Tridgell
   5  * Copyright (C) 1996 Paul Mackerras
   6  * Copyright (C) 2003-2020 Wayne Davison
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 3 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License along
  19  * with this program; if not, visit the http://fsf.org website.
  20  */
  21
  22 #include "rsync.h"
  23 #include "itypes.h"
  24 #include <zlib.h>
  25 #ifdef SUPPORT_ZSTD
  26 #include <zstd.h>
  27 #endif
  28 #ifdef SUPPORT_LZ4
  29 #include <lz4.h>
  30 #endif
  31
  32 extern int do_compression;
  33 extern int protocol_version;
  34 extern int module_id;
  35 extern int do_compression_level;
  36 extern char *skip_compress;
  37
  38 #ifndef Z_INSERT_ONLY
  39 #define Z_INSERT_ONLY Z_SYNC_FLUSH
  40 #endif
  41
  42 static int compression_level; /* The compression level for the current file. */
  43 static int skip_compression_level; /* The least possible compressing for handling skip-compress files. */
  44 static int per_file_default_level; /* The default level that each new file gets prior to checking its suffix. */
  45
  46 struct suffix_tree {
  47         struct suffix_tree *sibling;
  48         struct suffix_tree *child;
  49         char letter, word_end;
  50 };
  51
  52 static char *match_list;
  53 static struct suffix_tree *suftree;
  54
  55 void init_compression_level(void)
  56 {
  57         int min_level, max_level, def_level, off_level;
  58
  59         switch (do_compression) {
  60         case CPRES_NONE:
  61                 return;
  62         case CPRES_ZLIB:
  63         case CPRES_ZLIBX:
  64                 min_level = 1;
  65                 max_level = Z_BEST_COMPRESSION;
  66                 def_level = 6; /* Z_DEFAULT_COMPRESSION is -1, so set it to the real default */
  67                 off_level = skip_compression_level = Z_NO_COMPRESSION;
  68                 if (do_compression_level == Z_DEFAULT_COMPRESSION)
  69                         do_compression_level = def_level;
  70                 break;
  71 #ifdef SUPPORT_ZSTD
  72         case CPRES_ZSTD:
  73                 min_level = skip_compression_level = ZSTD_minCLevel();
  74                 max_level = ZSTD_maxCLevel();
  75                 def_level = ZSTD_CLEVEL_DEFAULT;
  76                 off_level = CLVL_NOT_SPECIFIED;
  77                 if (do_compression_level == 0)
  78                         do_compression_level = def_level;
  79                 break;
  80 #endif
  81 #ifdef SUPPORT_LZ4
  82         case CPRES_LZ4:
  83                 min_level = skip_compression_level = 0;
  84                 max_level = 0;
  85                 def_level = 0;
  86                 off_level = CLVL_NOT_SPECIFIED;
  87                 break;
  88 #endif
  89         default: /* paranoia to prevent missing case values */
  90                 assert(0);
  91         }
  92
  93         if (do_compression_level == CLVL_NOT_SPECIFIED)
  94                 do_compression_level = def_level;
  95         else if (do_compression_level == off_level) {
  96                 do_compression = CPRES_NONE;
  97                 return;
  98         }
  99
 100         /* We don't bother with any errors or warnings -- just make sure that the values are valid. */
 101         if (do_compression_level < min_level)
 102                 do_compression_level = min_level;
 103         else if (do_compression_level > max_level)
 104                 do_compression_level = max_level;
 105 }
 106
 107 static void add_suffix(struct suffix_tree **prior, char ltr, const char *str)
 108 {
 109         struct suffix_tree *node, *newnode;
 110
 111         if (ltr == '[') {
 112                 const char *after = strchr(str, ']');
 113                 /* Treat "[foo" and "[]" as having a literal '['. */
 114                 if (after && after++ != str+1) {
 115                         while ((ltr = *str++) != ']')
 116                                 add_suffix(prior, ltr, after);
 117                         return;
 118                 }
 119         }
 120
 121         for (node = *prior; node; prior = &node->sibling, node = node->sibling) {
 122                 if (node->letter == ltr) {
 123                         if (*str)
 124                                 add_suffix(&node->child, *str, str+1);
 125                         else
 126                                 node->word_end = 1;
 127                         return;
 128                 }
 129                 if (node->letter > ltr)
 130                         break;
 131         }
 132         if (!(newnode = new(struct suffix_tree)))
 133                 out_of_memory("add_suffix");
 134         newnode->sibling = node;
 135         newnode->child = NULL;
 136         newnode->letter = ltr;
 137         *prior = newnode;
 138         if (*str) {
 139                 add_suffix(&newnode->child, *str, str+1);
 140                 newnode->word_end = 0;
 141         } else
 142                 newnode->word_end = 1;
 143 }
 144
 145 static void add_nocompress_suffixes(const char *str)
 146 {
 147         char *buf, *t;
 148         const char *f = str;
 149
 150         if (!(buf = new_array(char, strlen(f) + 1)))
 151                 out_of_memory("add_nocompress_suffixes");
 152
 153         while (*f) {
 154                 if (*f == '/') {
 155                         f++;
 156                         continue;
 157                 }
 158
 159                 t = buf;
 160                 do {
 161                         if (isUpper(f))
 162                                 *t++ = toLower(f);
 163                         else
 164                                 *t++ = *f;
 165                 } while (*++f != '/' && *f);
 166                 *t++ = '\0';
 167
 168                 add_suffix(&suftree, *buf, buf+1);
 169         }
 170
 171         free(buf);
 172 }
 173
 174 static void init_set_compression(void)
 175 {
 176         const char *f;
 177         char *t, *start;
 178
 179         if (skip_compress)
 180                 add_nocompress_suffixes(skip_compress);
 181
 182         /* A non-daemon transfer skips the default suffix list if the
 183          * user specified --skip-compress. */
 184         if (skip_compress && module_id < 0)
 185                 f = "";
 186         else
 187                 f = lp_dont_compress(module_id);
 188
 189         if (!(match_list = t = new_array(char, strlen(f) + 2)))
 190                 out_of_memory("set_compression");
 191
 192         per_file_default_level = do_compression_level;
 193
 194         while (*f) {
 195                 if (*f == ' ') {
 196                         f++;
 197                         continue;
 198                 }
 199
 200                 start = t;
 201                 do {
 202                         if (isUpper(f))
 203                                 *t++ = toLower(f);
 204                         else
 205                                 *t++ = *f;
 206                 } while (*++f != ' ' && *f);
 207                 *t++ = '\0';
 208
 209                 if (t - start == 1+1 && *start == '*') {
 210                         /* Optimize a match-string of "*". */
 211                         *match_list = '\0';
 212                         suftree = NULL;
 213                         per_file_default_level = skip_compression_level;
 214                         break;
 215                 }
 216
 217                 /* Move *.foo items into the stuffix tree. */
 218                 if (*start == '*' && start[1] == '.' && start[2]
 219                  && !strpbrk(start+2, ".?*")) {
 220                         add_suffix(&suftree, start[2], start+3);
 221                         t = start;
 222                 }
 223         }
 224         *t++ = '\0';
 225 }
 226
 227 /* determine the compression level based on a wildcard filename list */
 228 void set_compression(const char *fname)
 229 {
 230         const struct suffix_tree *node;
 231         const char *s;
 232         char ltr;
 233
 234         if (!do_compression)
 235                 return;
 236
 237         if (!match_list)
 238                 init_set_compression();
 239
 240         compression_level = per_file_default_level;
 241
 242         if (!*match_list && !suftree)
 243                 return;
 244
 245         if ((s = strrchr(fname, '/')) != NULL)
 246                 fname = s + 1;
 247
 248         for (s = match_list; *s; s += strlen(s) + 1) {
 249                 if (iwildmatch(s, fname)) {
 250                         compression_level = skip_compression_level;
 251                         return;
 252                 }
 253         }
 254
 255         if (!(node = suftree) || !(s = strrchr(fname, '.'))
 256          || s == fname || !(ltr = *++s))
 257                 return;
 258
 259         while (1) {
 260                 if (isUpper(&ltr))
 261                         ltr = toLower(&ltr);
 262                 while (node->letter != ltr) {
 263                         if (node->letter > ltr)
 264                                 return;
 265                         if (!(node = node->sibling))
 266                                 return;
 267                 }
 268                 if ((ltr = *++s) == '\0') {
 269                         if (node->word_end)
 270                                 compression_level = skip_compression_level;
 271                         return;
 272                 }
 273                 if (!(node = node->child))
 274                         return;
 275         }
 276 }
 277
 278 /* non-compressing recv token */
 279 static int32 simple_recv_token(int f, char **data)
 280 {
 281         static int32 residue;
 282         static char *buf;
 283         int32 n;
 284
 285         if (!buf) {
 286                 buf = new_array(char, CHUNK_SIZE);
 287                 if (!buf)
 288                         out_of_memory("simple_recv_token");
 289         }
 290
 291         if (residue == 0) {
 292                 int32 i = read_int(f);
 293                 if (i <= 0)
 294                         return i;
 295                 residue = i;
 296         }
 297
 298         *data = buf;
 299         n = MIN(CHUNK_SIZE,residue);
 300         residue -= n;
 301         read_buf(f,buf,n);
 302         return n;
 303 }
 304
 305 /* non-compressing send token */
 306 static void simple_send_token(int f, int32 token, struct map_struct *buf, OFF_T offset, int32 n)
 307 {
 308         if (n > 0) {
 309                 int32 len = 0;
 310                 while (len < n) {
 311                         int32 n1 = MIN(CHUNK_SIZE, n-len);
 312                         write_int(f, n1);
 313                         write_buf(f, map_ptr(buf, offset+len, n1), n1);
 314                         len += n1;
 315                 }
 316         }
 317         /* a -2 token means to send data only and no token */
 318         if (token != -2)
 319                 write_int(f, -(token+1));
 320 }
 321
 322 /* Flag bytes in compressed stream are encoded as follows: */
 323 #define END_FLAG        0       /* that's all folks */
 324 #define TOKEN_LONG      0x20    /* followed by 32-bit token number */
 325 #define TOKENRUN_LONG   0x21    /* ditto with 16-bit run count */
 326 #define DEFLATED_DATA   0x40    /* + 6-bit high len, then low len byte */
 327 #define TOKEN_REL       0x80    /* + 6-bit relative token number */
 328 #define TOKENRUN_REL    0xc0    /* ditto with 16-bit run count */
 329
 330 #define MAX_DATA_COUNT  16383   /* fit 14 bit count into 2 bytes with flags */
 331
 332 /* zlib.h says that if we want to be able to compress something in a single
 333  * call, avail_out must be at least 0.1% larger than avail_in plus 12 bytes.
 334  * We'll add in 0.1%+16, just to be safe (and we'll avoid floating point,
 335  * to ensure that this is a compile-time value). */
 336 #define AVAIL_OUT_SIZE(avail_in_size) ((avail_in_size)*1001/1000+16)
 337
 338 /* For coding runs of tokens */
 339 static int32 last_token = -1;
 340 static int32 run_start;
 341 static int32 last_run_end;
 342
 343 /* Deflation state */
 344 static z_stream tx_strm;
 345
 346 /* Output buffer */
 347 static char *obuf;
 348
 349 /* We want obuf to be able to hold both MAX_DATA_COUNT+2 bytes as well as
 350  * AVAIL_OUT_SIZE(CHUNK_SIZE) bytes, so make sure that it's large enough. */
 351 #if MAX_DATA_COUNT+2 > AVAIL_OUT_SIZE(CHUNK_SIZE)
 352 #define OBUF_SIZE       (MAX_DATA_COUNT+2)
 353 #else
 354 #define OBUF_SIZE       AVAIL_OUT_SIZE(CHUNK_SIZE)
 355 #endif
 356
 357 /* Send a deflated token */
 358 static void
 359 send_deflated_token(int f, int32 token, struct map_struct *buf, OFF_T offset, int32 nb, int32 toklen)
 360 {
 361         static int init_done, flush_pending;
 362         int32 n, r;
 363
 364         if (last_token == -1) {
 365                 /* initialization */
 366                 if (!init_done) {
 367                         tx_strm.next_in = NULL;
 368                         tx_strm.zalloc = NULL;
 369                         tx_strm.zfree = NULL;
 370                         if (deflateInit2(&tx_strm, compression_level,
 371                                          Z_DEFLATED, -15, 8,
 372                                          Z_DEFAULT_STRATEGY) != Z_OK) {
 373                                 rprintf(FERROR, "compression init failed\n");
 374                                 exit_cleanup(RERR_PROTOCOL);
 375                         }
 376                         if ((obuf = new_array(char, OBUF_SIZE)) == NULL)
 377                                 out_of_memory("send_deflated_token");
 378                         init_done = 1;
 379                 } else
 380                         deflateReset(&tx_strm);
 381                 last_run_end = 0;
 382                 run_start = token;
 383                 flush_pending = 0;
 384         } else if (last_token == -2) {
 385                 run_start = token;
 386         } else if (nb != 0 || token != last_token + 1
 387                    || token >= run_start + 65536) {
 388                 /* output previous run */
 389                 r = run_start - last_run_end;
 390                 n = last_token - run_start;
 391                 if (r >= 0 && r <= 63) {
 392                         write_byte(f, (n==0? TOKEN_REL: TOKENRUN_REL) + r);
 393                 } else {
 394                         write_byte(f, (n==0? TOKEN_LONG: TOKENRUN_LONG));
 395                         write_int(f, run_start);
 396                 }
 397                 if (n != 0) {
 398                         write_byte(f, n);
 399                         write_byte(f, n >> 8);
 400                 }
 401                 last_run_end = last_token;
 402                 run_start = token;
 403         }
 404
 405         last_token = token;
 406
 407         if (nb != 0 || flush_pending) {
 408                 /* deflate the data starting at offset */
 409                 int flush = Z_NO_FLUSH;
 410                 tx_strm.avail_in = 0;
 411                 tx_strm.avail_out = 0;
 412                 do {
 413                         if (tx_strm.avail_in == 0 && nb != 0) {
 414                                 /* give it some more input */
 415                                 n = MIN(nb, CHUNK_SIZE);
 416                                 tx_strm.next_in = (Bytef *)
 417                                         map_ptr(buf, offset, n);
 418                                 tx_strm.avail_in = n;
 419                                 nb -= n;
 420                                 offset += n;
 421                         }
 422                         if (tx_strm.avail_out == 0) {
 423                                 tx_strm.next_out = (Bytef *)(obuf + 2);
 424                                 tx_strm.avail_out = MAX_DATA_COUNT;
 425                                 if (flush != Z_NO_FLUSH) {
 426                                         /*
 427                                          * We left the last 4 bytes in the
 428                                          * buffer, in case they are the
 429                                          * last 4.  Move them to the front.
 430                                          */
 431                                         memcpy(tx_strm.next_out, obuf+MAX_DATA_COUNT-2, 4);
 432                                         tx_strm.next_out += 4;
 433                                         tx_strm.avail_out -= 4;
 434                                 }
 435                         }
 436                         if (nb == 0 && token != -2)
 437                                 flush = Z_SYNC_FLUSH;
 438                         r = deflate(&tx_strm, flush);
 439                         if (r != Z_OK) {
 440                                 rprintf(FERROR, "deflate returned %d\n", r);
 441                                 exit_cleanup(RERR_STREAMIO);
 442                         }
 443                         if (nb == 0 || tx_strm.avail_out == 0) {
 444                                 n = MAX_DATA_COUNT - tx_strm.avail_out;
 445                                 if (flush != Z_NO_FLUSH) {
 446                                         /*
 447                                          * We have to trim off the last 4
 448                                          * bytes of output when flushing
 449                                          * (they are just 0, 0, ff, ff).
 450                                          */
 451                                         n -= 4;
 452                                 }
 453                                 if (n > 0) {
 454                                         obuf[0] = DEFLATED_DATA + (n >> 8);
 455                                         obuf[1] = n;
 456                                         write_buf(f, obuf, n+2);
 457                                 }
 458                         }
 459                 } while (nb != 0 || tx_strm.avail_out == 0);
 460                 flush_pending = token == -2;
 461         }
 462
 463         if (token == -1) {
 464                 /* end of file - clean up */
 465                 write_byte(f, END_FLAG);
 466         } else if (token != -2 && do_compression == CPRES_ZLIB) {
 467                 /* Add the data in the current block to the compressor's
 468                  * history and hash table. */
 469                 do {
 470                         /* Break up long sections in the same way that
 471                          * see_deflate_token() does. */
 472                         int32 n1 = toklen > 0xffff ? 0xffff : toklen;
 473                         toklen -= n1;
 474                         tx_strm.next_in = (Bytef *)map_ptr(buf, offset, n1);
 475                         tx_strm.avail_in = n1;
 476                         if (protocol_version >= 31) /* Newer protocols avoid a data-duplicating bug */
 477                                 offset += n1;
 478                         tx_strm.next_out = (Bytef *) obuf;
 479                         tx_strm.avail_out = AVAIL_OUT_SIZE(CHUNK_SIZE);
 480                         r = deflate(&tx_strm, Z_INSERT_ONLY);
 481                         if (r != Z_OK || tx_strm.avail_in != 0) {
 482                                 rprintf(FERROR, "deflate on token returned %d (%d bytes left)\n",
 483                                         r, tx_strm.avail_in);
 484                                 exit_cleanup(RERR_STREAMIO);
 485                         }
 486                 } while (toklen > 0);
 487         }
 488 }
 489
 490 /* tells us what the receiver is in the middle of doing */
 491 static enum { r_init, r_idle, r_running, r_inflating, r_inflated } recv_state;
 492
 493 /* for inflating stuff */
 494 static z_stream rx_strm;
 495 static char *cbuf;
 496 static char *dbuf;
 497
 498 /* for decoding runs of tokens */
 499 static int32 rx_token;
 500 static int32 rx_run;
 501
 502 /* Receive a deflated token and inflate it */
 503 static int32 recv_deflated_token(int f, char **data)
 504 {
 505         static int init_done;
 506         static int32 saved_flag;
 507         int32 n, flag;
 508         int r;
 509
 510         for (;;) {
 511                 switch (recv_state) {
 512                 case r_init:
 513                         if (!init_done) {
 514                                 rx_strm.next_out = NULL;
 515                                 rx_strm.zalloc = NULL;
 516                                 rx_strm.zfree = NULL;
 517                                 if (inflateInit2(&rx_strm, -15) != Z_OK) {
 518                                         rprintf(FERROR, "inflate init failed\n");
 519                                         exit_cleanup(RERR_PROTOCOL);
 520                                 }
 521                                 if (!(cbuf = new_array(char, MAX_DATA_COUNT))
 522                                  || !(dbuf = new_array(char, AVAIL_OUT_SIZE(CHUNK_SIZE))))
 523                                         out_of_memory("recv_deflated_token");
 524                                 init_done = 1;
 525                         } else {
 526                                 inflateReset(&rx_strm);
 527                         }
 528                         recv_state = r_idle;
 529                         rx_token = 0;
 530                         break;
 531
 532                 case r_idle:
 533                 case r_inflated:
 534                         if (saved_flag) {
 535                                 flag = saved_flag & 0xff;
 536                                 saved_flag = 0;
 537                         } else
 538                                 flag = read_byte(f);
 539                         if ((flag & 0xC0) == DEFLATED_DATA) {
 540                                 n = ((flag & 0x3f) << 8) + read_byte(f);
 541                                 read_buf(f, cbuf, n);
 542                                 rx_strm.next_in = (Bytef *)cbuf;
 543                                 rx_strm.avail_in = n;
 544                                 recv_state = r_inflating;
 545                                 break;
 546                         }
 547                         if (recv_state == r_inflated) {
 548                                 /* check previous inflated stuff ended correctly */
 549                                 rx_strm.avail_in = 0;
 550                                 rx_strm.next_out = (Bytef *)dbuf;
 551                                 rx_strm.avail_out = AVAIL_OUT_SIZE(CHUNK_SIZE);
 552                                 r = inflate(&rx_strm, Z_SYNC_FLUSH);
 553                                 n = AVAIL_OUT_SIZE(CHUNK_SIZE) - rx_strm.avail_out;
 554                                 /*
 555                                  * Z_BUF_ERROR just means no progress was
 556                                  * made, i.e. the decompressor didn't have
 557                                  * any pending output for us.
 558                                  */
 559                                 if (r != Z_OK && r != Z_BUF_ERROR) {
 560                                         rprintf(FERROR, "inflate flush returned %d (%d bytes)\n",
 561                                                 r, n);
 562                                         exit_cleanup(RERR_STREAMIO);
 563                                 }
 564                                 if (n != 0 && r != Z_BUF_ERROR) {
 565                                         /* have to return some more data and
 566                                            save the flag for later. */
 567                                         saved_flag = flag + 0x10000;
 568                                         *data = dbuf;
 569                                         return n;
 570                                 }
 571                                 /*
 572                                  * At this point the decompressor should
 573                                  * be expecting to see the 0, 0, ff, ff bytes.
 574                                  */
 575                                 if (!inflateSyncPoint(&rx_strm)) {
 576                                         rprintf(FERROR, "decompressor lost sync!\n");
 577                                         exit_cleanup(RERR_STREAMIO);
 578                                 }
 579                                 rx_strm.avail_in = 4;
 580                                 rx_strm.next_in = (Bytef *)cbuf;
 581                                 cbuf[0] = cbuf[1] = 0;
 582                                 cbuf[2] = cbuf[3] = 0xff;
 583                                 inflate(&rx_strm, Z_SYNC_FLUSH);
 584                                 recv_state = r_idle;
 585                         }
 586                         if (flag == END_FLAG) {
 587                                 /* that's all folks */
 588                                 recv_state = r_init;
 589                                 return 0;
 590                         }
 591
 592                         /* here we have a token of some kind */
 593                         if (flag & TOKEN_REL) {
 594                                 rx_token += flag & 0x3f;
 595                                 flag >>= 6;
 596                         } else
 597                                 rx_token = read_int(f);
 598                         if (flag & 1) {
 599                                 rx_run = read_byte(f);
 600                                 rx_run += read_byte(f) << 8;
 601                                 recv_state = r_running;
 602                         }
 603                         return -1 - rx_token;
 604
 605                 case r_inflating:
 606                         rx_strm.next_out = (Bytef *)dbuf;
 607                         rx_strm.avail_out = AVAIL_OUT_SIZE(CHUNK_SIZE);
 608                         r = inflate(&rx_strm, Z_NO_FLUSH);
 609                         n = AVAIL_OUT_SIZE(CHUNK_SIZE) - rx_strm.avail_out;
 610                         if (r != Z_OK) {
 611                                 rprintf(FERROR, "inflate returned %d (%d bytes)\n", r, n);
 612                                 exit_cleanup(RERR_STREAMIO);
 613                         }
 614                         if (rx_strm.avail_in == 0)
 615                                 recv_state = r_inflated;
 616                         if (n != 0) {
 617                                 *data = dbuf;
 618                                 return n;
 619                         }
 620                         break;
 621
 622                 case r_running:
 623                         ++rx_token;
 624                         if (--rx_run == 0)
 625                                 recv_state = r_idle;
 626                         return -1 - rx_token;
 627                 }
 628         }
 629 }
 630
 631 /*
 632  * put the data corresponding to a token that we've just returned
 633  * from recv_deflated_token into the decompressor's history buffer.
 634  */
 635 static void see_deflate_token(char *buf, int32 len)
 636 {
 637         int r;
 638         int32 blklen;
 639         unsigned char hdr[5];
 640
 641         rx_strm.avail_in = 0;
 642         blklen = 0;
 643         hdr[0] = 0;
 644         do {
 645                 if (rx_strm.avail_in == 0 && len != 0) {
 646                         if (blklen == 0) {
 647                                 /* Give it a fake stored-block header. */
 648                                 rx_strm.next_in = (Bytef *)hdr;
 649                                 rx_strm.avail_in = 5;
 650                                 blklen = len;
 651                                 if (blklen > 0xffff)
 652                                         blklen = 0xffff;
 653                                 hdr[1] = blklen;
 654                                 hdr[2] = blklen >> 8;
 655                                 hdr[3] = ~hdr[1];
 656                                 hdr[4] = ~hdr[2];
 657                         } else {
 658                                 rx_strm.next_in = (Bytef *)buf;
 659                                 rx_strm.avail_in = blklen;
 660                                 if (protocol_version >= 31) /* Newer protocols avoid a data-duplicating bug */
 661                                         buf += blklen;
 662                                 len -= blklen;
 663                                 blklen = 0;
 664                         }
 665                 }
 666                 rx_strm.next_out = (Bytef *)dbuf;
 667                 rx_strm.avail_out = AVAIL_OUT_SIZE(CHUNK_SIZE);
 668                 r = inflate(&rx_strm, Z_SYNC_FLUSH);
 669                 if (r != Z_OK && r != Z_BUF_ERROR) {
 670                         rprintf(FERROR, "inflate (token) returned %d\n", r);
 671                         exit_cleanup(RERR_STREAMIO);
 672                 }
 673         } while (len || rx_strm.avail_out == 0);
 674 }
 675
 676 #ifdef SUPPORT_ZSTD
 677
 678 static ZSTD_inBuffer zstd_in_buff;
 679 static ZSTD_outBuffer zstd_out_buff;
 680 static ZSTD_CCtx *zstd_cctx;
 681
 682 static void send_zstd_token(int f, int32 token, struct map_struct *buf, OFF_T offset, int32 nb)
 683 {
 684         static int comp_init_done, flush_pending;
 685         ZSTD_EndDirective flush = ZSTD_e_continue;
 686         int32 n, r;
 687
 688         /* initialization */
 689         if (!comp_init_done) {
 690
 691                 zstd_cctx = ZSTD_createCCtx();
 692                 if (!zstd_cctx) {
 693                         rprintf(FERROR, "compression init failed\n");
 694                         exit_cleanup(RERR_PROTOCOL);
 695                 }
 696
 697                 obuf = new_array(char, OBUF_SIZE);
 698                 if (!obuf)
 699                         out_of_memory("send_deflated_token");
 700
 701                 ZSTD_CCtx_setParameter(zstd_cctx, ZSTD_c_compressionLevel, do_compression_level);
 702                 zstd_out_buff.dst = obuf + 2;
 703
 704                 comp_init_done = 1;
 705         }
 706
 707         if (last_token == -1) {
 708                 last_run_end = 0;
 709                 run_start = token;
 710                 flush_pending = 0;
 711         } else if (last_token == -2) {
 712                 run_start = token;
 713
 714         } else if (nb != 0 || token != last_token + 1
 715                    || token >= run_start + 65536) {
 716
 717                 /* output previous run */
 718                 r = run_start - last_run_end;
 719                 n = last_token - run_start;
 720
 721                 if (r >= 0 && r <= 63) {
 722                         write_byte(f, (n==0? TOKEN_REL: TOKENRUN_REL) + r);
 723                 } else {
 724                         write_byte(f, (n==0? TOKEN_LONG: TOKENRUN_LONG));
 725                         write_int(f, run_start);
 726                 }
 727                 if (n != 0) {
 728                         write_byte(f, n);
 729                         write_byte(f, n >> 8);
 730                 }
 731                 last_run_end = last_token;
 732                 run_start = token;
 733         }
 734
 735         last_token = token;
 736
 737         if (nb || flush_pending) {
 738
 739                 zstd_in_buff.src = map_ptr(buf, offset, nb);
 740                 zstd_in_buff.size = nb;
 741                 zstd_in_buff.pos = 0;
 742
 743                 do {
 744                         if (zstd_out_buff.size == 0) {
 745                                 zstd_out_buff.size = MAX_DATA_COUNT;
 746                                 zstd_out_buff.pos = 0;
 747                         }
 748
 749                         /* File ended, flush */
 750                         if (token != -2)
 751                                 flush = ZSTD_e_flush;
 752
 753                         r = ZSTD_compressStream2(zstd_cctx, &zstd_out_buff, &zstd_in_buff, flush);
 754                         if (ZSTD_isError(r)) {
 755                                 rprintf(FERROR, "ZSTD_compressStream returned %d\n", r);
 756                                 exit_cleanup(RERR_STREAMIO);
 757                         }
 758
 759                         /*
 760                          * Nothing is sent if the buffer isn't full so avoid smaller
 761                          * transfers. If a file is finished then we flush the internal
 762                          * state and send a smaller buffer so that the remote side can
 763                          * finish the file.
 764                          */
 765                         if (zstd_out_buff.pos == zstd_out_buff.size || flush == ZSTD_e_flush) {
 766                                 n = zstd_out_buff.pos;
 767
 768                                 obuf[0] = DEFLATED_DATA + (n >> 8);
 769                                 obuf[1] = n;
 770                                 write_buf(f, obuf, n+2);
 771
 772                                 zstd_out_buff.size = 0;
 773                         }
 774                         /*
 775                          * Loop while the input buffer isn't full consumed or the
 776                          * internal state isn't fully flushed.
 777                          */
 778                 } while (zstd_in_buff.pos < zstd_in_buff.size || r > 0);
 779                 flush_pending = token == -2;
 780         }
 781
 782         if (token == -1) {
 783                 /* end of file - clean up */
 784                 write_byte(f, END_FLAG);
 785         }
 786 }
 787
 788 static ZSTD_DCtx *zstd_dctx;
 789
 790 static int32 recv_zstd_token(int f, char **data)
 791 {
 792         static int decomp_init_done;
 793         static int out_buffer_size;
 794         int32 n, flag;
 795         int r;
 796
 797         if (!decomp_init_done) {
 798
 799                 zstd_dctx = ZSTD_createDCtx();
 800                 if (!zstd_dctx) {
 801                         rprintf(FERROR, "ZSTD_createDStream failed\n");
 802                         exit_cleanup(RERR_PROTOCOL);
 803                 }
 804
 805                 /* Output buffer fits two decompressed blocks */
 806                 out_buffer_size = ZSTD_DStreamOutSize() * 2;
 807                 cbuf = new_array(char, MAX_DATA_COUNT);
 808                 dbuf = new_array(char, out_buffer_size);
 809                 if (!cbuf || !dbuf)
 810                         out_of_memory("recv_zstd_token");
 811
 812                 zstd_in_buff.src = cbuf;
 813                 zstd_out_buff.dst = dbuf;
 814
 815                 decomp_init_done = 1;
 816         }
 817
 818         do {
 819         switch (recv_state) {
 820         case r_init:
 821                 recv_state = r_idle;
 822                 rx_token = 0;
 823                 break;
 824
 825         case r_idle:
 826                 flag = read_byte(f);
 827                 if ((flag & 0xC0) == DEFLATED_DATA) {
 828                         n = ((flag & 0x3f) << 8) + read_byte(f);
 829                         read_buf(f, cbuf, n);
 830
 831                         zstd_in_buff.size = n;
 832                         zstd_in_buff.pos = 0;
 833
 834                         recv_state = r_inflating;
 835
 836                 } else if (flag == END_FLAG) {
 837                         /* that's all folks */
 838                         recv_state = r_init;
 839                         return 0;
 840
 841                 } else {
 842                         /* here we have a token of some kind */
 843                         if (flag & TOKEN_REL) {
 844                                 rx_token += flag & 0x3f;
 845                                 flag >>= 6;
 846                         } else
 847                                 rx_token = read_int(f);
 848                         if (flag & 1) {
 849                                 rx_run = read_byte(f);
 850                                 rx_run += read_byte(f) << 8;
 851                                 recv_state = r_running;
 852                         }
 853                         return -1 - rx_token;
 854                 }
 855                 break;
 856
 857         case r_inflating:
 858                 zstd_out_buff.size = out_buffer_size;
 859                 zstd_out_buff.pos = 0;
 860
 861                 r = ZSTD_decompressStream(zstd_dctx, &zstd_out_buff, &zstd_in_buff);
 862                 n = zstd_out_buff.pos;
 863                 if (ZSTD_isError(r)) {
 864                         rprintf(FERROR, "ZSTD decomp returned %d (%d bytes)\n", r, n);
 865                         exit_cleanup(RERR_STREAMIO);
 866                 }
 867
 868                 /*
 869                  * If the input buffer is fully consumed and the output
 870                  * buffer is not full then next step is to read more
 871                  * data.
 872                  */
 873                 if (zstd_in_buff.size == zstd_in_buff.pos && n < out_buffer_size)
 874                         recv_state = r_idle;
 875
 876                 if (n != 0) {
 877                         *data = dbuf;
 878                         return n;
 879                 }
 880                 break;
 881
 882         case r_running:
 883                 ++rx_token;
 884                 if (--rx_run == 0)
 885                         recv_state = r_idle;
 886                 return -1 - rx_token;
 887                 break;
 888
 889         case r_inflated:
 890                 break;
 891         }
 892         } while (1);
 893 }
 894 #endif /* SUPPORT_ZSTD */
 895
 896 #ifdef SUPPORT_LZ4
 897 static void
 898 send_compressed_token(int f, int32 token, struct map_struct *buf, OFF_T offset, int32 nb)
 899 {
 900         static int init_done, flush_pending;
 901         int size = MAX(LZ4_compressBound(CHUNK_SIZE), MAX_DATA_COUNT+2);
 902         int32 n, r;
 903
 904         if (last_token == -1) {
 905                 if (!init_done) {
 906                         if ((obuf = new_array(char, size)) == NULL)
 907                                 out_of_memory("send_compressed_token");
 908                         init_done = 1;
 909                 }
 910                 last_run_end = 0;
 911                 run_start = token;
 912                 flush_pending = 0;
 913         } else if (last_token == -2) {
 914                 run_start = token;
 915         } else if (nb != 0 || token != last_token + 1
 916                    || token >= run_start + 65536) {
 917                 /* output previous run */
 918                 r = run_start - last_run_end;
 919                 n = last_token - run_start;
 920                 if (r >= 0 && r <= 63) {
 921                         write_byte(f, (n==0? TOKEN_REL: TOKENRUN_REL) + r);
 922                 } else {
 923                         write_byte(f, (n==0? TOKEN_LONG: TOKENRUN_LONG));
 924                         write_int(f, run_start);
 925                 }
 926                 if (n != 0) {
 927                         write_byte(f, n);
 928                         write_byte(f, n >> 8);
 929                 }
 930                 last_run_end = last_token;
 931                 run_start = token;
 932         }
 933
 934         last_token = token;
 935
 936         if (nb != 0 || flush_pending) {
 937                 int available_in, available_out = 0;
 938                 const char *next_in;
 939
 940                 do {
 941                         char *ptr = obuf;
 942                         char *next_out = obuf + 2;
 943
 944                         if (available_out == 0) {
 945                                 available_in = MIN(nb, MAX_DATA_COUNT);
 946                                 next_in = map_ptr(buf, offset, available_in);
 947                         } else
 948                                 available_in /= 2;
 949
 950                         available_out = LZ4_compress_default(next_in, next_out, available_in, size - 2);
 951                         if (!available_out) {
 952                                 rprintf(FERROR, "compress returned %d\n", available_out);
 953                                 exit_cleanup(RERR_STREAMIO);
 954                         }
 955                         if (available_out <= MAX_DATA_COUNT) {
 956                                 ptr[0] = DEFLATED_DATA + (available_out >> 8);
 957                                 ptr[1] = available_out;
 958
 959                                 write_buf(f, ptr, available_out + 2);
 960
 961                                 available_out = 0;
 962                                 nb -= available_in;
 963                                 offset += available_in;
 964                         }
 965                 } while (nb != 0);
 966                 flush_pending = token == -2;
 967         }
 968         if (token == -1)
 969                 /* end of file - clean up */
 970                 write_byte(f, END_FLAG);
 971 }
 972
 973 static int32 recv_compressed_token(int f, char **data)
 974 {
 975         static int32 saved_flag;
 976         static int init_done;
 977         int32 n, flag;
 978         int size = MAX(LZ4_compressBound(CHUNK_SIZE), MAX_DATA_COUNT+2);
 979         static const char *next_in;
 980         static int avail_in;
 981         int avail_out;
 982
 983         for (;;) {
 984                 switch (recv_state) {
 985                 case r_init:
 986                         if (!init_done) {
 987                                 if (!(cbuf = new_array(char, MAX_DATA_COUNT))
 988                                  || !(dbuf = new_array(char, size)))
 989                                         out_of_memory("recv_compressed_token");
 990                                 init_done = 1;
 991                         }
 992                         recv_state = r_idle;
 993                         rx_token = 0;
 994                         break;
 995                 case r_idle:
 996                 case r_inflated:
 997                         if (saved_flag) {
 998                                 flag = saved_flag & 0xff;
 999                                 saved_flag = 0;
1000                         } else
1001                                 flag = read_byte(f);
1002                         if ((flag & 0xC0) == DEFLATED_DATA) {
1003                                 n = ((flag & 0x3f) << 8) + read_byte(f);
1004                                 read_buf(f, cbuf, n);
1005                                 next_in = (char *)cbuf;
1006                                 avail_in = n;
1007                                 recv_state = r_inflating;
1008                                 break;
1009                         }
1010
1011                         if (recv_state == r_inflated)
1012                                 recv_state = r_idle;
1013
1014                         if (flag == END_FLAG) {
1015                                 /* that's all folks */
1016                                 recv_state = r_init;
1017                                 return 0;
1018                         }
1019
1020                         /* here we have a token of some kind */
1021                         if (flag & TOKEN_REL) {
1022                                 rx_token += flag & 0x3f;
1023                                 flag >>= 6;
1024                         } else
1025                                 rx_token = read_int(f);
1026                         if (flag & 1) {
1027                                 rx_run = read_byte(f);
1028                                 rx_run += read_byte(f) << 8;
1029                                 recv_state = r_running;
1030                         }
1031                         return -1 - rx_token;
1032
1033                 case r_inflating:
1034                         avail_out = LZ4_decompress_safe(next_in, dbuf, avail_in, size);
1035                         if (avail_out < 0) {
1036                                 rprintf(FERROR, "uncompress failed: %d\n", avail_out);
1037                                 exit_cleanup(RERR_STREAMIO);
1038                         }
1039                         recv_state = r_inflated;
1040                         *data = dbuf;
1041                         return avail_out;
1042
1043                 case r_running:
1044                         ++rx_token;
1045                         if (--rx_run == 0)
1046                                 recv_state = r_idle;
1047                         return -1 - rx_token;
1048                 }
1049         }
1050
1051 }
1052
1053 # if 0
1054 static void see_uncompressed_token(char *buf, int32 len)
1055 {
1056         static const char *next_in;
1057         static int avail_in;
1058         int avail_out;
1059
1060         int32 blklen;
1061         char hdr[5];
1062
1063         avail_in = 0;
1064         blklen = 0;
1065         hdr[0] = 0;
1066         do {
1067                 if (avail_in == 0 && len != 0) {
1068                         if (blklen == 0) {
1069                                 /* Give it a fake stored-block header. */
1070                                 next_in = hdr;
1071                                 avail_in = 5;
1072                                 blklen = len;
1073                                 if (blklen > 0xffff)
1074                                         blklen = 0xffff;
1075                                 hdr[1] = blklen;
1076                                 hdr[2] = blklen >> 8;
1077                                 hdr[3] = ~hdr[1];
1078                                 hdr[4] = ~hdr[2];
1079                         } else {
1080                                 next_in = (char *)buf;
1081                                 avail_in = blklen;
1082                                 if (protocol_version >= 31) /* Newer protocols avoid a data-duplicating bug */
1083                                         buf += blklen;
1084                                 len -= blklen;
1085                                 blklen = 0;
1086                         }
1087                 }
1088                 avail_out = LZ4_decompress_safe(next_in, dbuf, avail_in, LZ4_compressBound(CHUNK_SIZE));
1089                 if (avail_out < 0) {
1090                         rprintf(FERROR, "uncompress failed: %d\n", avail_out);
1091                         exit_cleanup(RERR_STREAMIO);
1092                 }
1093
1094         } while (len);
1095 }
1096 # endif /* 0 */
1097 #endif /* SUPPORT_LZ4 */
1098
1099 /**
1100  * Transmit a verbatim buffer of length @p n followed by a token.
1101  * If token == -1 then we have reached EOF
1102  * If n == 0 then don't send a buffer
1103  */
1104 void send_token(int f, int32 token, struct map_struct *buf, OFF_T offset,
1105                 int32 n, int32 toklen)
1106 {
1107         switch (do_compression) {
1108         case CPRES_NONE:
1109                 simple_send_token(f, token, buf, offset, n);
1110                 break;
1111         case CPRES_ZLIB:
1112         case CPRES_ZLIBX:
1113                 send_deflated_token(f, token, buf, offset, n, toklen);
1114                 break;
1115 #ifdef SUPPORT_ZSTD
1116         case CPRES_ZSTD:
1117                 send_zstd_token(f, token, buf, offset, n);
1118                 break;
1119 #endif
1120 #ifdef SUPPORT_LZ4
1121         case CPRES_LZ4:
1122                 send_compressed_token(f, token, buf, offset, n);
1123                 break;
1124 #endif
1125         default:
1126                 assert(0);
1127         }
1128 }
1129
1130 /*
1131  * receive a token or buffer from the other end. If the return value is >0 then
1132  * it is a data buffer of that length, and *data will point at the data.
1133  * if the return value is -i then it represents token i-1
1134  * if the return value is 0 then the end has been reached
1135  */
1136 int32 recv_token(int f, char **data)
1137 {
1138         switch (do_compression) {
1139         case CPRES_NONE:
1140                 return simple_recv_token(f,data);
1141         case CPRES_ZLIB:
1142         case CPRES_ZLIBX:
1143                 return recv_deflated_token(f, data);
1144 #ifdef SUPPORT_ZSTD
1145         case CPRES_ZSTD:
1146                 return recv_zstd_token(f, data);
1147 #endif
1148 #ifdef SUPPORT_LZ4
1149         case CPRES_LZ4:
1150                 return recv_compressed_token(f, data);
1151 #endif
1152         default:
1153                 assert(0);
1154         }
1155 }
1156
1157 /*
1158  * look at the data corresponding to a token, if necessary
1159  */
1160 void see_token(char *data, int32 toklen)
1161 {
1162         switch (do_compression) {
1163         case CPRES_NONE:
1164                 break;
1165         case CPRES_ZLIB:
1166                 see_deflate_token(data, toklen);
1167                 break;
1168         case CPRES_ZLIBX:
1169                 break;
1170 #ifdef SUPPORT_LZ4
1171         case CPRES_LZ4:
1172                 /*see_uncompressed_token(data, toklen);*/
1173                 break;
1174 #endif
1175 #ifdef SUPPORT_LZ4
1176         case CPRES_ZSTD:
1177                 break;
1178 #endif
1179         default:
1180                 assert(0);
1181         }
1182 }