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 extern int module_id;
  25 extern int def_compress_level;
  26
  27 static int compression_level;
  28
  29 /* determine the compression level based on a wildcard filename list */
  30 void set_compression(char *fname)
  31 {
  32         char *dont;
  33         char *tok;
  34
  35         if (!do_compression)
  36                 return;
  37
  38         compression_level = def_compress_level;
  39         dont = lp_dont_compress(module_id);
  40
  41         if (!dont || !*dont)
  42                 return;
  43
  44         if (dont[0] == '*' && !dont[1]) {
  45                 /* an optimization to skip the rest of this routine */
  46                 compression_level = 0;
  47                 return;
  48         }
  49
  50         if ((tok = strrchr(fname, '/')) != NULL)
  51                 fname = tok + 1;
  52
  53         dont = strdup(dont);
  54         fname = strdup(fname);
  55         if (!dont || !fname)
  56                 return;
  57
  58         strlower(dont);
  59         strlower(fname);
  60
  61         for (tok = strtok(dont, " "); tok; tok = strtok(NULL, " ")) {
  62                 if (wildmatch(tok, fname)) {
  63                         compression_level = 0;
  64                         break;
  65                 }
  66         }
  67         free(dont);
  68         free(fname);
  69 }
  70
  71 /* non-compressing recv token */
  72 static int32 simple_recv_token(int f, char **data)
  73 {
  74         static int32 residue;
  75         static char *buf;
  76         int32 n;
  77
  78         if (!buf) {
  79                 buf = new_array(char, CHUNK_SIZE);
  80                 if (!buf)
  81                         out_of_memory("simple_recv_token");
  82         }
  83
  84         if (residue == 0) {
  85                 int32 i = read_int(f);
  86                 if (i <= 0)
  87                         return i;
  88                 residue = i;
  89         }
  90
  91         *data = buf;
  92         n = MIN(CHUNK_SIZE,residue);
  93         residue -= n;
  94         read_buf(f,buf,n);
  95         return n;
  96 }
  97
  98
  99 /* non-compressing send token */
 100 static void simple_send_token(int f, int32 token, struct map_struct *buf,
 101                               OFF_T offset, int32 n)
 102 {
 103         if (n > 0) {
 104                 int32 len = 0;
 105                 while (len < n) {
 106                         int32 n1 = MIN(CHUNK_SIZE, n-len);
 107                         write_int(f, n1);
 108                         write_buf(f, map_ptr(buf, offset+len, n1), n1);
 109                         len += n1;
 110                 }
 111         }
 112         /* a -2 token means to send data only and no token */
 113         if (token != -2)
 114                 write_int(f, -(token+1));
 115 }
 116
 117
 118 /* Flag bytes in compressed stream are encoded as follows: */
 119 #define END_FLAG        0       /* that's all folks */
 120 #define TOKEN_LONG      0x20    /* followed by 32-bit token number */
 121 #define TOKENRUN_LONG   0x21    /* ditto with 16-bit run count */
 122 #define DEFLATED_DATA   0x40    /* + 6-bit high len, then low len byte */
 123 #define TOKEN_REL       0x80    /* + 6-bit relative token number */
 124 #define TOKENRUN_REL    0xc0    /* ditto with 16-bit run count */
 125
 126 #define MAX_DATA_COUNT  16383   /* fit 14 bit count into 2 bytes with flags */
 127
 128 /* zlib.h says that if we want to be able to compress something in a single
 129  * call, avail_out must be at least 0.1% larger than avail_in plus 12 bytes.
 130  * We'll add in 0.1%+16, just to be safe (and we'll avoid floating point,
 131  * to ensure that this is a compile-time value). */
 132 #define AVAIL_OUT_SIZE(avail_in_size) ((avail_in_size)*1001/1000+16)
 133
 134 /* For coding runs of tokens */
 135 static int32 last_token = -1;
 136 static int32 run_start;
 137 static int32 last_run_end;
 138
 139 /* Deflation state */
 140 static z_stream tx_strm;
 141
 142 /* Output buffer */
 143 static char *obuf;
 144
 145 /* We want obuf to be able to hold both MAX_DATA_COUNT+2 bytes as well as
 146  * AVAIL_OUT_SIZE(CHUNK_SIZE) bytes, so make sure that it's large enough. */
 147 #if MAX_DATA_COUNT+2 > AVAIL_OUT_SIZE(CHUNK_SIZE)
 148 #define OBUF_SIZE       (MAX_DATA_COUNT+2)
 149 #else
 150 #define OBUF_SIZE       AVAIL_OUT_SIZE(CHUNK_SIZE)
 151 #endif
 152
 153 /* Send a deflated token */
 154 static void
 155 send_deflated_token(int f, int32 token, struct map_struct *buf, OFF_T offset,
 156                     int32 nb, int32 toklen)
 157 {
 158         int32 n, r;
 159         static int init_done, flush_pending;
 160
 161         if (last_token == -1) {
 162                 /* initialization */
 163                 if (!init_done) {
 164                         tx_strm.next_in = NULL;
 165                         tx_strm.zalloc = NULL;
 166                         tx_strm.zfree = NULL;
 167                         if (deflateInit2(&tx_strm, compression_level,
 168                                          Z_DEFLATED, -15, 8,
 169                                          Z_DEFAULT_STRATEGY) != Z_OK) {
 170                                 rprintf(FERROR, "compression init failed\n");
 171                                 exit_cleanup(RERR_STREAMIO);
 172                         }
 173                         if ((obuf = new_array(char, OBUF_SIZE)) == NULL)
 174                                 out_of_memory("send_deflated_token");
 175                         init_done = 1;
 176                 } else
 177                         deflateReset(&tx_strm);
 178                 last_run_end = 0;
 179                 run_start = token;
 180                 flush_pending = 0;
 181
 182         } else if (last_token == -2) {
 183                 run_start = token;
 184
 185         } else if (nb != 0 || token != last_token + 1
 186                    || token >= run_start + 65536) {
 187                 /* output previous run */
 188                 r = run_start - last_run_end;
 189                 n = last_token - run_start;
 190                 if (r >= 0 && r <= 63) {
 191                         write_byte(f, (n==0? TOKEN_REL: TOKENRUN_REL) + r);
 192                 } else {
 193                         write_byte(f, (n==0? TOKEN_LONG: TOKENRUN_LONG));
 194                         write_int(f, run_start);
 195                 }
 196                 if (n != 0) {
 197                         write_byte(f, n);
 198                         write_byte(f, n >> 8);
 199                 }
 200                 last_run_end = last_token;
 201                 run_start = token;
 202         }
 203
 204         last_token = token;
 205
 206         if (nb != 0 || flush_pending) {
 207                 /* deflate the data starting at offset */
 208                 int flush = Z_NO_FLUSH;
 209                 tx_strm.avail_in = 0;
 210                 tx_strm.avail_out = 0;
 211                 do {
 212                         if (tx_strm.avail_in == 0 && nb != 0) {
 213                                 /* give it some more input */
 214                                 n = MIN(nb, CHUNK_SIZE);
 215                                 tx_strm.next_in = (Bytef *)
 216                                         map_ptr(buf, offset, n);
 217                                 tx_strm.avail_in = n;
 218                                 nb -= n;
 219                                 offset += n;
 220                         }
 221                         if (tx_strm.avail_out == 0) {
 222                                 tx_strm.next_out = (Bytef *)(obuf + 2);
 223                                 tx_strm.avail_out = MAX_DATA_COUNT;
 224                                 if (flush != Z_NO_FLUSH) {
 225                                         /*
 226                                          * We left the last 4 bytes in the
 227                                          * buffer, in case they are the
 228                                          * last 4.  Move them to the front.
 229                                          */
 230                                         memcpy(tx_strm.next_out,
 231                                                obuf+MAX_DATA_COUNT-2, 4);
 232                                         tx_strm.next_out += 4;
 233                                         tx_strm.avail_out -= 4;
 234                                 }
 235                         }
 236                         if (nb == 0 && token != -2)
 237                                 flush = Z_SYNC_FLUSH;
 238                         r = deflate(&tx_strm, flush);
 239                         if (r != Z_OK) {
 240                                 rprintf(FERROR, "deflate returned %d\n", r);
 241                                 exit_cleanup(RERR_STREAMIO);
 242                         }
 243                         if (nb == 0 || tx_strm.avail_out == 0) {
 244                                 n = MAX_DATA_COUNT - tx_strm.avail_out;
 245                                 if (flush != Z_NO_FLUSH) {
 246                                         /*
 247                                          * We have to trim off the last 4
 248                                          * bytes of output when flushing
 249                                          * (they are just 0, 0, ff, ff).
 250                                          */
 251                                         n -= 4;
 252                                 }
 253                                 if (n > 0) {
 254                                         obuf[0] = DEFLATED_DATA + (n >> 8);
 255                                         obuf[1] = n;
 256                                         write_buf(f, obuf, n+2);
 257                                 }
 258                         }
 259                 } while (nb != 0 || tx_strm.avail_out == 0);
 260                 flush_pending = token == -2;
 261         }
 262
 263         if (token == -1) {
 264                 /* end of file - clean up */
 265                 write_byte(f, END_FLAG);
 266         } else if (token != -2) {
 267                 /* Add the data in the current block to the compressor's
 268                  * history and hash table. */
 269                 do {
 270                         /* Break up long sections in the same way that
 271                          * see_deflate_token() does. */
 272                         int32 n1 = toklen > 0xffff ? 0xffff : toklen;
 273                         toklen -= n1;
 274                         tx_strm.next_in = (Bytef *)map_ptr(buf, offset, n1);
 275                         tx_strm.avail_in = n1;
 276                         tx_strm.next_out = (Bytef *) obuf;
 277                         tx_strm.avail_out = AVAIL_OUT_SIZE(CHUNK_SIZE);
 278                         r = deflate(&tx_strm, Z_INSERT_ONLY);
 279                         if (r != Z_OK || tx_strm.avail_in != 0) {
 280                                 rprintf(FERROR, "deflate on token returned %d (%d bytes left)\n",
 281                                         r, tx_strm.avail_in);
 282                                 exit_cleanup(RERR_STREAMIO);
 283                         }
 284                 } while (toklen > 0);
 285         }
 286 }
 287
 288
 289 /* tells us what the receiver is in the middle of doing */
 290 static enum { r_init, r_idle, r_running, r_inflating, r_inflated } recv_state;
 291
 292 /* for inflating stuff */
 293 static z_stream rx_strm;
 294 static char *cbuf;
 295 static char *dbuf;
 296
 297 /* for decoding runs of tokens */
 298 static int32 rx_token;
 299 static int32 rx_run;
 300
 301 /* Receive a deflated token and inflate it */
 302 static int32 recv_deflated_token(int f, char **data)
 303 {
 304         static int init_done;
 305         static int32 saved_flag;
 306         int32 n, flag;
 307         int r;
 308
 309         for (;;) {
 310                 switch (recv_state) {
 311                 case r_init:
 312                         if (!init_done) {
 313                                 rx_strm.next_out = NULL;
 314                                 rx_strm.zalloc = NULL;
 315                                 rx_strm.zfree = NULL;
 316                                 if (inflateInit2(&rx_strm, -15) != Z_OK) {
 317                                         rprintf(FERROR, "inflate init failed\n");
 318                                         exit_cleanup(RERR_STREAMIO);
 319                                 }
 320                                 if (!(cbuf = new_array(char, MAX_DATA_COUNT))
 321                                     || !(dbuf = new_array(char, AVAIL_OUT_SIZE(CHUNK_SIZE))))
 322                                         out_of_memory("recv_deflated_token");
 323                                 init_done = 1;
 324                         } else {
 325                                 inflateReset(&rx_strm);
 326                         }
 327                         recv_state = r_idle;
 328                         rx_token = 0;
 329                         break;
 330
 331                 case r_idle:
 332                 case r_inflated:
 333                         if (saved_flag) {
 334                                 flag = saved_flag & 0xff;
 335                                 saved_flag = 0;
 336                         } else
 337                                 flag = read_byte(f);
 338                         if ((flag & 0xC0) == DEFLATED_DATA) {
 339                                 n = ((flag & 0x3f) << 8) + read_byte(f);
 340                                 read_buf(f, cbuf, n);
 341                                 rx_strm.next_in = (Bytef *)cbuf;
 342                                 rx_strm.avail_in = n;
 343                                 recv_state = r_inflating;
 344                                 break;
 345                         }
 346                         if (recv_state == r_inflated) {
 347                                 /* check previous inflated stuff ended correctly */
 348                                 rx_strm.avail_in = 0;
 349                                 rx_strm.next_out = (Bytef *)dbuf;
 350                                 rx_strm.avail_out = AVAIL_OUT_SIZE(CHUNK_SIZE);
 351                                 r = inflate(&rx_strm, Z_SYNC_FLUSH);
 352                                 n = AVAIL_OUT_SIZE(CHUNK_SIZE) - rx_strm.avail_out;
 353                                 /*
 354                                  * Z_BUF_ERROR just means no progress was
 355                                  * made, i.e. the decompressor didn't have
 356                                  * any pending output for us.
 357                                  */
 358                                 if (r != Z_OK && r != Z_BUF_ERROR) {
 359                                         rprintf(FERROR, "inflate flush returned %d (%d bytes)\n",
 360                                                 r, n);
 361                                         exit_cleanup(RERR_STREAMIO);
 362                                 }
 363                                 if (n != 0 && r != Z_BUF_ERROR) {
 364                                         /* have to return some more data and
 365                                            save the flag for later. */
 366                                         saved_flag = flag + 0x10000;
 367                                         *data = dbuf;
 368                                         return n;
 369                                 }
 370                                 /*
 371                                  * At this point the decompressor should
 372                                  * be expecting to see the 0, 0, ff, ff bytes.
 373                                  */
 374                                 if (!inflateSyncPoint(&rx_strm)) {
 375                                         rprintf(FERROR, "decompressor lost sync!\n");
 376                                         exit_cleanup(RERR_STREAMIO);
 377                                 }
 378                                 rx_strm.avail_in = 4;
 379                                 rx_strm.next_in = (Bytef *)cbuf;
 380                                 cbuf[0] = cbuf[1] = 0;
 381                                 cbuf[2] = cbuf[3] = 0xff;
 382                                 inflate(&rx_strm, Z_SYNC_FLUSH);
 383                                 recv_state = r_idle;
 384                         }
 385                         if (flag == END_FLAG) {
 386                                 /* that's all folks */
 387                                 recv_state = r_init;
 388                                 return 0;
 389                         }
 390
 391                         /* here we have a token of some kind */
 392                         if (flag & TOKEN_REL) {
 393                                 rx_token += flag & 0x3f;
 394                                 flag >>= 6;
 395                         } else
 396                                 rx_token = read_int(f);
 397                         if (flag & 1) {
 398                                 rx_run = read_byte(f);
 399                                 rx_run += read_byte(f) << 8;
 400                                 recv_state = r_running;
 401                         }
 402                         return -1 - rx_token;
 403
 404                 case r_inflating:
 405                         rx_strm.next_out = (Bytef *)dbuf;
 406                         rx_strm.avail_out = AVAIL_OUT_SIZE(CHUNK_SIZE);
 407                         r = inflate(&rx_strm, Z_NO_FLUSH);
 408                         n = AVAIL_OUT_SIZE(CHUNK_SIZE) - rx_strm.avail_out;
 409                         if (r != Z_OK) {
 410                                 rprintf(FERROR, "inflate returned %d (%d bytes)\n", r, n);
 411                                 exit_cleanup(RERR_STREAMIO);
 412                         }
 413                         if (rx_strm.avail_in == 0)
 414                                 recv_state = r_inflated;
 415                         if (n != 0) {
 416                                 *data = dbuf;
 417                                 return n;
 418                         }
 419                         break;
 420
 421                 case r_running:
 422                         ++rx_token;
 423                         if (--rx_run == 0)
 424                                 recv_state = r_idle;
 425                         return -1 - rx_token;
 426                 }
 427         }
 428 }
 429
 430 /*
 431  * put the data corresponding to a token that we've just returned
 432  * from recv_deflated_token into the decompressor's history buffer.
 433  */
 434 static void see_deflate_token(char *buf, int32 len)
 435 {
 436         int r;
 437         int32 blklen;
 438         unsigned char hdr[5];
 439
 440         rx_strm.avail_in = 0;
 441         blklen = 0;
 442         hdr[0] = 0;
 443         do {
 444                 if (rx_strm.avail_in == 0 && len != 0) {
 445                         if (blklen == 0) {
 446                                 /* Give it a fake stored-block header. */
 447                                 rx_strm.next_in = (Bytef *)hdr;
 448                                 rx_strm.avail_in = 5;
 449                                 blklen = len;
 450                                 if (blklen > 0xffff)
 451                                         blklen = 0xffff;
 452                                 hdr[1] = blklen;
 453                                 hdr[2] = blklen >> 8;
 454                                 hdr[3] = ~hdr[1];
 455                                 hdr[4] = ~hdr[2];
 456                         } else {
 457                                 rx_strm.next_in = (Bytef *)buf;
 458                                 rx_strm.avail_in = blklen;
 459                                 len -= blklen;
 460                                 blklen = 0;
 461                         }
 462                 }
 463                 rx_strm.next_out = (Bytef *)dbuf;
 464                 rx_strm.avail_out = AVAIL_OUT_SIZE(CHUNK_SIZE);
 465                 r = inflate(&rx_strm, Z_SYNC_FLUSH);
 466                 if (r != Z_OK) {
 467                         rprintf(FERROR, "inflate (token) returned %d\n", r);
 468                         exit_cleanup(RERR_STREAMIO);
 469                 }
 470         } while (len || rx_strm.avail_out == 0);
 471 }
 472
 473 /**
 474  * Transmit a verbatim buffer of length @p n followed by a token.
 475  * If token == -1 then we have reached EOF
 476  * If n == 0 then don't send a buffer
 477  */
 478 void send_token(int f, int32 token, struct map_struct *buf, OFF_T offset,
 479                 int32 n, int32 toklen)
 480 {
 481         if (!do_compression)
 482                 simple_send_token(f, token, buf, offset, n);
 483         else
 484                 send_deflated_token(f, token, buf, offset, n, toklen);
 485 }
 486
 487
 488 /*
 489  * receive a token or buffer from the other end. If the reurn value is >0 then
 490  * it is a data buffer of that length, and *data will point at the data.
 491  * if the return value is -i then it represents token i-1
 492  * if the return value is 0 then the end has been reached
 493  */
 494 int32 recv_token(int f, char **data)
 495 {
 496         int tok;
 497
 498         if (!do_compression) {
 499                 tok = simple_recv_token(f,data);
 500         } else {
 501                 tok = recv_deflated_token(f, data);
 502         }
 503         return tok;
 504 }
 505
 506 /*
 507  * look at the data corresponding to a token, if necessary
 508  */
 509 void see_token(char *data, int32 toklen)
 510 {
 511         if (do_compression)
 512                 see_deflate_token(data, toklen);
 513 }