token.c

   1 /*
   2    Copyright (C) Andrew Tridgell 1996
   3    Copyright (C) Paul Mackerras 1996
   4
   5    This program is free software; you can redistribute it and/or modify
   6    it under the terms of the GNU General Public License as published by
   7    the Free Software Foundation; either version 2 of the License, or
   8    (at your option) any later version.
   9
  10    This program is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13    GNU General Public License for more details.
  14
  15    You should have received a copy of the GNU General Public License
  16    along with this program; if not, write to the Free Software
  17    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  18 */
  19
  20 #include "rsync.h"
  21 #include "zlib/zlib.h"
  22
  23 extern int do_compression;
  24 static int compression_level = Z_DEFAULT_COMPRESSION;
  25
  26 /* determine the compression level based on a wildcard filename list */
  27 void set_compression(char *fname)
  28 {
  29         extern int module_id;
  30         char *dont;
  31         char *tok;
  32
  33         if (!do_compression) return;
  34
  35         compression_level = Z_DEFAULT_COMPRESSION;
  36         dont = lp_dont_compress(module_id);
  37
  38         if (!dont || !*dont) return;
  39
  40         if ((dont[0] == '*') && (!dont[1])) {
  41                 /* an optimization to skip the rest of this routine */
  42                 compression_level = 0;
  43                 return;
  44         }
  45
  46         dont = strdup(dont);
  47         fname = strdup(fname);
  48         if (!dont || !fname) return;
  49
  50         strlower(dont);
  51         strlower(fname);
  52
  53         for (tok=strtok(dont," ");tok;tok=strtok(NULL," ")) {
  54                 if (wildmatch(tok, fname)) {
  55                         compression_level = 0;
  56                         break;
  57                 }
  58         }
  59         free(dont);
  60         free(fname);
  61 }
  62
  63 /* non-compressing recv token */
  64 static int simple_recv_token(int f,char **data)
  65 {
  66         static int residue;
  67         static char *buf;
  68         int n;
  69
  70         if (!buf) {
  71                 buf = new_array(char, CHUNK_SIZE);
  72                 if (!buf) out_of_memory("simple_recv_token");
  73         }
  74
  75         if (residue == 0) {
  76                 int i = read_int(f);
  77                 if (i <= 0) return i;
  78                 residue = i;
  79         }
  80
  81         *data = buf;
  82         n = MIN(CHUNK_SIZE,residue);
  83         residue -= n;
  84         read_buf(f,buf,n);
  85         return n;
  86 }
  87
  88
  89 /* non-compressing send token */
  90 static void simple_send_token(int f,int token,
  91                               struct map_struct *buf,OFF_T offset,int n)
  92 {
  93         extern int write_batch;
  94         int hold_int;
  95
  96         if (n > 0) {
  97                 int l = 0;
  98                 while (l < n) {
  99                         int n1 = MIN(CHUNK_SIZE,n-l);
 100                         write_int(f,n1);
 101                         write_buf(f,map_ptr(buf,offset+l,n1),n1);
 102                         if (write_batch) {
 103                                 write_batch_delta_file( (char *) &n1, sizeof(int) );
 104                                 write_batch_delta_file(map_ptr(buf,offset+l,n1),n1);
 105                         }
 106                         l += n1;
 107                 }
 108         }
 109         /* a -2 token means to send data only and no token */
 110         if (token != -2) {
 111                 write_int(f,-(token+1));
 112                 if (write_batch) {
 113                         hold_int = -(token+1);
 114                         write_batch_delta_file( (char *) &hold_int, sizeof(int) );
 115                 }
 116         }
 117 }
 118
 119
 120 /* Flag bytes in compressed stream are encoded as follows: */
 121 #define END_FLAG        0       /* that's all folks */
 122 #define TOKEN_LONG      0x20    /* followed by 32-bit token number */
 123 #define TOKENRUN_LONG   0x21    /* ditto with 16-bit run count */
 124 #define DEFLATED_DATA   0x40    /* + 6-bit high len, then low len byte */
 125 #define TOKEN_REL       0x80    /* + 6-bit relative token number */
 126 #define TOKENRUN_REL    0xc0    /* ditto with 16-bit run count */
 127
 128 #define MAX_DATA_COUNT  16383   /* fit 14 bit count into 2 bytes with flags */
 129
 130 /* zlib.h says that if we want to be able to compress something in a single
 131  * call, avail_out must be at least 0.1% larger than avail_in plus 12 bytes.
 132  * We'll add in 0.1%+16, just to be safe (and we'll avoid floating point,
 133  * to ensure that this is a compile-time value). */
 134 #define AVAIL_OUT_SIZE(avail_in_size) ((avail_in_size)*1001/1000+16)
 135
 136 /* For coding runs of tokens */
 137 static int last_token = -1;
 138 static int run_start;
 139 static int last_run_end;
 140
 141 /* Deflation state */
 142 static z_stream tx_strm;
 143
 144 /* Output buffer */
 145 static char *obuf;
 146
 147 /* We want obuf to be able to hold both MAX_DATA_COUNT+2 bytes as well as
 148  * AVAIL_OUT_SIZE(CHUNK_SIZE) bytes, so make sure that it's large enough. */
 149 #if MAX_DATA_COUNT+2 > AVAIL_OUT_SIZE(CHUNK_SIZE)
 150 #define OBUF_SIZE       (MAX_DATA_COUNT+2)
 151 #else
 152 #define OBUF_SIZE       AVAIL_OUT_SIZE(CHUNK_SIZE)
 153 #endif
 154
 155 /* Send a deflated token */
 156 static void
 157 send_deflated_token(int f, int token,
 158                     struct map_struct *buf, OFF_T offset, int nb, int toklen)
 159 {
 160         int n, r;
 161         static int init_done, flush_pending;
 162         extern int write_batch;
 163         char temp_byte;
 164
 165         if (last_token == -1) {
 166                 /* initialization */
 167                 if (!init_done) {
 168                         tx_strm.next_in = NULL;
 169                         tx_strm.zalloc = NULL;
 170                         tx_strm.zfree = NULL;
 171                         if (deflateInit2(&tx_strm, compression_level,
 172                                          Z_DEFLATED, -15, 8,
 173                                          Z_DEFAULT_STRATEGY) != Z_OK) {
 174                                 rprintf(FERROR, "compression init failed\n");
 175                                 exit_cleanup(RERR_STREAMIO);
 176                         }
 177                         if ((obuf = new_array(char, OBUF_SIZE)) == NULL)
 178                                 out_of_memory("send_deflated_token");
 179                         init_done = 1;
 180                 } else
 181                         deflateReset(&tx_strm);
 182                 last_run_end = 0;
 183                 run_start = token;
 184                 flush_pending = 0;
 185
 186         } else if (last_token == -2) {
 187                 run_start = token;
 188
 189         } else if (nb != 0 || token != last_token + 1
 190                    || token >= run_start + 65536) {
 191                 /* output previous run */
 192                 r = run_start - last_run_end;
 193                 n = last_token - run_start;
 194                 if (r >= 0 && r <= 63) {
 195                         write_byte(f, (n==0? TOKEN_REL: TOKENRUN_REL) + r);
 196                         if (write_batch) {
 197                                 temp_byte = (char)( (n==0? TOKEN_REL: TOKENRUN_REL) + r);
 198                                 write_batch_delta_file(&temp_byte,sizeof(char));
 199                         }
 200                 } else {
 201                         write_byte(f, (n==0? TOKEN_LONG: TOKENRUN_LONG));
 202                         write_int(f, run_start);
 203                         if (write_batch) {
 204                                 temp_byte = (char)(n==0? TOKEN_LONG: TOKENRUN_LONG);
 205                                 write_batch_delta_file(&temp_byte,sizeof(char));
 206                                 write_batch_delta_file((char *)&run_start,sizeof(run_start));
 207                         }
 208                 }
 209                 if (n != 0) {
 210                         write_byte(f, n);
 211                         write_byte(f, n >> 8);
 212                         if (write_batch) {
 213                                 temp_byte = (char)n;
 214                                 write_batch_delta_file(&temp_byte,sizeof(char));
 215                                 temp_byte = (char)(n >> 8);
 216                                 write_batch_delta_file(&temp_byte,sizeof(char));
 217                         }
 218                 }
 219                 last_run_end = last_token;
 220                 run_start = token;
 221         }
 222
 223         last_token = token;
 224
 225         if (nb != 0 || flush_pending) {
 226                 /* deflate the data starting at offset */
 227                 int flush = Z_NO_FLUSH;
 228                 tx_strm.avail_in = 0;
 229                 tx_strm.avail_out = 0;
 230                 do {
 231                         if (tx_strm.avail_in == 0 && nb != 0) {
 232                                 /* give it some more input */
 233                                 n = MIN(nb, CHUNK_SIZE);
 234                                 tx_strm.next_in = (Bytef *)
 235                                         map_ptr(buf, offset, n);
 236                                 tx_strm.avail_in = n;
 237                                 nb -= n;
 238                                 offset += n;
 239                         }
 240                         if (tx_strm.avail_out == 0) {
 241                                 tx_strm.next_out = (Bytef *)(obuf + 2);
 242                                 tx_strm.avail_out = MAX_DATA_COUNT;
 243                                 if (flush != Z_NO_FLUSH) {
 244                                         /*
 245                                          * We left the last 4 bytes in the
 246                                          * buffer, in case they are the
 247                                          * last 4.  Move them to the front.
 248                                          */
 249                                         memcpy(tx_strm.next_out,
 250                                                obuf+MAX_DATA_COUNT-2, 4);
 251                                         tx_strm.next_out += 4;
 252                                         tx_strm.avail_out -= 4;
 253                                 }
 254                         }
 255                         if (nb == 0 && token != -2)
 256                                 flush = Z_SYNC_FLUSH;
 257                         r = deflate(&tx_strm, flush);
 258                         if (r != Z_OK) {
 259                                 rprintf(FERROR, "deflate returned %d\n", r);
 260                                 exit_cleanup(RERR_STREAMIO);
 261                         }
 262                         if (nb == 0 || tx_strm.avail_out == 0) {
 263                                 n = MAX_DATA_COUNT - tx_strm.avail_out;
 264                                 if (flush != Z_NO_FLUSH) {
 265                                         /*
 266                                          * We have to trim off the last 4
 267                                          * bytes of output when flushing
 268                                          * (they are just 0, 0, ff, ff).
 269                                          */
 270                                         n -= 4;
 271                                 }
 272                                 if (n > 0) {
 273                                         obuf[0] = DEFLATED_DATA + (n >> 8);
 274                                         obuf[1] = n;
 275                                         write_buf(f, obuf, n+2);
 276                                         if (write_batch)
 277                                                 write_batch_delta_file(obuf,n+2);
 278                                 }
 279                         }
 280                 } while (nb != 0 || tx_strm.avail_out == 0);
 281                 flush_pending = token == -2;
 282         }
 283
 284         if (token == -1) {
 285                 /* end of file - clean up */
 286                 write_byte(f, END_FLAG);
 287                 if (write_batch) {
 288                         temp_byte = END_FLAG;
 289                         write_batch_delta_file(&temp_byte,sizeof(char));
 290                 }
 291
 292         } else if (token != -2) {
 293                 /* add the data in the current block to the compressor's
 294                    history and hash table */
 295                 tx_strm.next_in = (Bytef *) map_ptr(buf, offset, toklen);
 296                 tx_strm.avail_in = toklen;
 297                 tx_strm.next_out = (Bytef *) obuf;
 298                 tx_strm.avail_out = AVAIL_OUT_SIZE(CHUNK_SIZE);
 299                 r = deflate(&tx_strm, Z_INSERT_ONLY);
 300                 if (r != Z_OK || tx_strm.avail_in != 0) {
 301                         rprintf(FERROR, "deflate on token returned %d (%d bytes left)\n",
 302                                 r, tx_strm.avail_in);
 303                         exit_cleanup(RERR_STREAMIO);
 304                 }
 305         }
 306 }
 307
 308
 309 /* tells us what the receiver is in the middle of doing */
 310 static enum { r_init, r_idle, r_running, r_inflating, r_inflated } recv_state;
 311
 312 /* for inflating stuff */
 313 static z_stream rx_strm;
 314 static char *cbuf;
 315 static char *dbuf;
 316
 317 /* for decoding runs of tokens */
 318 static int rx_token;
 319 static int rx_run;
 320
 321 /* Receive a deflated token and inflate it */
 322 static int
 323 recv_deflated_token(int f, char **data)
 324 {
 325         int n, r, flag;
 326         static int init_done;
 327         static int saved_flag;
 328
 329         for (;;) {
 330                 switch (recv_state) {
 331                 case r_init:
 332                         if (!init_done) {
 333                                 rx_strm.next_out = NULL;
 334                                 rx_strm.zalloc = NULL;
 335                                 rx_strm.zfree = NULL;
 336                                 if (inflateInit2(&rx_strm, -15) != Z_OK) {
 337                                         rprintf(FERROR, "inflate init failed\n");
 338                                         exit_cleanup(RERR_STREAMIO);
 339                                 }
 340                                 if (!(cbuf = new_array(char, MAX_DATA_COUNT))
 341                                     || !(dbuf = new_array(char, AVAIL_OUT_SIZE(CHUNK_SIZE))))
 342                                         out_of_memory("recv_deflated_token");
 343                                 init_done = 1;
 344                         } else {
 345                                 inflateReset(&rx_strm);
 346                         }
 347                         recv_state = r_idle;
 348                         rx_token = 0;
 349                         break;
 350
 351                 case r_idle:
 352                 case r_inflated:
 353                         if (saved_flag) {
 354                                 flag = saved_flag & 0xff;
 355                                 saved_flag = 0;
 356                         } else
 357                                 flag = read_byte(f);
 358                         if ((flag & 0xC0) == DEFLATED_DATA) {
 359                                 n = ((flag & 0x3f) << 8) + read_byte(f);
 360                                 read_buf(f, cbuf, n);
 361                                 rx_strm.next_in = (Bytef *)cbuf;
 362                                 rx_strm.avail_in = n;
 363                                 recv_state = r_inflating;
 364                                 break;
 365                         }
 366                         if (recv_state == r_inflated) {
 367                                 /* check previous inflated stuff ended correctly */
 368                                 rx_strm.avail_in = 0;
 369                                 rx_strm.next_out = (Bytef *)dbuf;
 370                                 rx_strm.avail_out = AVAIL_OUT_SIZE(CHUNK_SIZE);
 371                                 r = inflate(&rx_strm, Z_SYNC_FLUSH);
 372                                 n = AVAIL_OUT_SIZE(CHUNK_SIZE) - rx_strm.avail_out;
 373                                 /*
 374                                  * Z_BUF_ERROR just means no progress was
 375                                  * made, i.e. the decompressor didn't have
 376                                  * any pending output for us.
 377                                  */
 378                                 if (r != Z_OK && r != Z_BUF_ERROR) {
 379                                         rprintf(FERROR, "inflate flush returned %d (%d bytes)\n",
 380                                                 r, n);
 381                                         exit_cleanup(RERR_STREAMIO);
 382                                 }
 383                                 if (n != 0 && r != Z_BUF_ERROR) {
 384                                         /* have to return some more data and
 385                                            save the flag for later. */
 386                                         saved_flag = flag + 0x10000;
 387                                         *data = dbuf;
 388                                         return n;
 389                                 }
 390                                 /*
 391                                  * At this point the decompressor should
 392                                  * be expecting to see the 0, 0, ff, ff bytes.
 393                                  */
 394                                 if (!inflateSyncPoint(&rx_strm)) {
 395                                         rprintf(FERROR, "decompressor lost sync!\n");
 396                                         exit_cleanup(RERR_STREAMIO);
 397                                 }
 398                                 rx_strm.avail_in = 4;
 399                                 rx_strm.next_in = (Bytef *)cbuf;
 400                                 cbuf[0] = cbuf[1] = 0;
 401                                 cbuf[2] = cbuf[3] = 0xff;
 402                                 inflate(&rx_strm, Z_SYNC_FLUSH);
 403                                 recv_state = r_idle;
 404                         }
 405                         if (flag == END_FLAG) {
 406                                 /* that's all folks */
 407                                 recv_state = r_init;
 408                                 return 0;
 409                         }
 410
 411                         /* here we have a token of some kind */
 412                         if (flag & TOKEN_REL) {
 413                                 rx_token += flag & 0x3f;
 414                                 flag >>= 6;
 415                         } else
 416                                 rx_token = read_int(f);
 417                         if (flag & 1) {
 418                                 rx_run = read_byte(f);
 419                                 rx_run += read_byte(f) << 8;
 420                                 recv_state = r_running;
 421                         }
 422                         return -1 - rx_token;
 423
 424                 case r_inflating:
 425                         rx_strm.next_out = (Bytef *)dbuf;
 426                         rx_strm.avail_out = AVAIL_OUT_SIZE(CHUNK_SIZE);
 427                         r = inflate(&rx_strm, Z_NO_FLUSH);
 428                         n = AVAIL_OUT_SIZE(CHUNK_SIZE) - rx_strm.avail_out;
 429                         if (r != Z_OK) {
 430                                 rprintf(FERROR, "inflate returned %d (%d bytes)\n", r, n);
 431                                 exit_cleanup(RERR_STREAMIO);
 432                         }
 433                         if (rx_strm.avail_in == 0)
 434                                 recv_state = r_inflated;
 435                         if (n != 0) {
 436                                 *data = dbuf;
 437                                 return n;
 438                         }
 439                         break;
 440
 441                 case r_running:
 442                         ++rx_token;
 443                         if (--rx_run == 0)
 444                                 recv_state = r_idle;
 445                         return -1 - rx_token;
 446                 }
 447         }
 448 }
 449
 450 /*
 451  * put the data corresponding to a token that we've just returned
 452  * from recv_deflated_token into the decompressor's history buffer.
 453  */
 454 static void see_deflate_token(char *buf, int len)
 455 {
 456         int r, blklen;
 457         unsigned char hdr[5];
 458
 459         rx_strm.avail_in = 0;
 460         blklen = 0;
 461         hdr[0] = 0;
 462         do {
 463                 if (rx_strm.avail_in == 0 && len != 0) {
 464                         if (blklen == 0) {
 465                                 /* Give it a fake stored-block header. */
 466                                 rx_strm.next_in = (Bytef *)hdr;
 467                                 rx_strm.avail_in = 5;
 468                                 blklen = len;
 469                                 if (blklen > 0xffff)
 470                                         blklen = 0xffff;
 471                                 hdr[1] = blklen;
 472                                 hdr[2] = blklen >> 8;
 473                                 hdr[3] = ~hdr[1];
 474                                 hdr[4] = ~hdr[2];
 475                         } else {
 476                                 rx_strm.next_in = (Bytef *)buf;
 477                                 rx_strm.avail_in = blklen;
 478                                 len -= blklen;
 479                                 blklen = 0;
 480                         }
 481                 }
 482                 rx_strm.next_out = (Bytef *)dbuf;
 483                 rx_strm.avail_out = AVAIL_OUT_SIZE(CHUNK_SIZE);
 484                 r = inflate(&rx_strm, Z_SYNC_FLUSH);
 485                 if (r != Z_OK) {
 486                         rprintf(FERROR, "inflate (token) returned %d\n", r);
 487                         exit_cleanup(RERR_STREAMIO);
 488                 }
 489         } while (len || rx_strm.avail_out == 0);
 490 }
 491
 492 /**
 493  * Transmit a verbatim buffer of length @p n followed by a token.
 494  * If token == -1 then we have reached EOF
 495  * If n == 0 then don't send a buffer
 496  */
 497 void send_token(int f,int token,struct map_struct *buf,OFF_T offset,
 498                 int n,int toklen)
 499 {
 500         if (!do_compression) {
 501                 simple_send_token(f,token,buf,offset,n);
 502         } else {
 503                 send_deflated_token(f, token, buf, offset, n, toklen);
 504         }
 505 }
 506
 507
 508 /*
 509  * receive a token or buffer from the other end. If the reurn value is >0 then
 510  * it is a data buffer of that length, and *data will point at the data.
 511  * if the return value is -i then it represents token i-1
 512  * if the return value is 0 then the end has been reached
 513  */
 514 int recv_token(int f,char **data)
 515 {
 516         int tok;
 517
 518         if (!do_compression) {
 519                 tok = simple_recv_token(f,data);
 520         } else {
 521                 tok = recv_deflated_token(f, data);
 522         }
 523         return tok;
 524 }
 525
 526 /*
 527  * look at the data corresponding to a token, if necessary
 528  */
 529 void see_token(char *data, int toklen)
 530 {
 531         if (do_compression)
 532                 see_deflate_token(data, toklen);
 533 }