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 (fnmatch(tok, fname, 0) == 0) {
  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 = (char *)malloc(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; /* dw */
  94         int hold_int; /* dw */
  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 /* For coding runs of tokens */
 131 static int last_token = -1;
 132 static int run_start;
 133 static int last_run_end;
 134
 135 /* Deflation state */
 136 static z_stream tx_strm;
 137
 138 /* Output buffer */
 139 static char *obuf;
 140
 141 /* Send a deflated token */
 142 static void
 143 send_deflated_token(int f, int token,
 144                     struct map_struct *buf, OFF_T offset, int nb, int toklen)
 145 {
 146         int n, r;
 147         static int init_done, flush_pending;
 148         extern int write_batch;  /* dw */
 149         char temp_byte;   /* dw */
 150
 151         if (last_token == -1) {
 152                 /* initialization */
 153                 if (!init_done) {
 154                         tx_strm.next_in = NULL;
 155                         tx_strm.zalloc = NULL;
 156                         tx_strm.zfree = NULL;
 157                         if (deflateInit2(&tx_strm, compression_level,
 158                                          Z_DEFLATED, -15, 8,
 159                                          Z_DEFAULT_STRATEGY) != Z_OK) {
 160                                 rprintf(FERROR, "compression init failed\n");
 161                                 exit_cleanup(RERR_STREAMIO);
 162                         }
 163                         if ((obuf = malloc(MAX_DATA_COUNT+2)) == NULL)
 164                                 out_of_memory("send_deflated_token");
 165                         init_done = 1;
 166                 } else
 167                         deflateReset(&tx_strm);
 168                 last_run_end = 0;
 169                 run_start = token;
 170                 flush_pending = 0;
 171
 172         } else if (last_token == -2) {
 173                 run_start = token;
 174
 175         } else if (nb != 0 || token != last_token + 1
 176                    || token >= run_start + 65536) {
 177                 /* output previous run */
 178                 r = run_start - last_run_end;
 179                 n = last_token - run_start;
 180                 if (r >= 0 && r <= 63) {
 181                         write_byte(f, (n==0? TOKEN_REL: TOKENRUN_REL) + r);
 182                         if (write_batch) { /* dw */
 183                             temp_byte = (char)( (n==0? TOKEN_REL: TOKENRUN_REL) + r);
 184                             write_batch_delta_file(&temp_byte,sizeof(char));
 185                         }
 186                 } else {
 187                         write_byte(f, (n==0? TOKEN_LONG: TOKENRUN_LONG));
 188                         write_int(f, run_start);
 189                         if (write_batch) { /* dw */
 190                             temp_byte = (char)(n==0? TOKEN_LONG: TOKENRUN_LONG);
 191                             write_batch_delta_file(&temp_byte,sizeof(temp_byte));
 192                             write_batch_delta_file((char *)&run_start,sizeof(run_start));
 193                         }
 194                 }
 195                 if (n != 0) {
 196                         write_byte(f, n);
 197                         write_byte(f, n >> 8);
 198                         if (write_batch) { /* dw */
 199                             write_batch_delta_file((char *)&n,sizeof(char));
 200                             temp_byte = (char) n >> 8;
 201                             write_batch_delta_file(&temp_byte,sizeof(temp_byte));
 202                         }
 203                 }
 204                 last_run_end = last_token;
 205                 run_start = token;
 206         }
 207
 208         last_token = token;
 209
 210         if (nb != 0 || flush_pending) {
 211                 /* deflate the data starting at offset */
 212                 int flush = Z_NO_FLUSH;
 213                 tx_strm.avail_in = 0;
 214                 tx_strm.avail_out = 0;
 215                 do {
 216                         if (tx_strm.avail_in == 0 && nb != 0) {
 217                                 /* give it some more input */
 218                                 n = MIN(nb, CHUNK_SIZE);
 219                                 tx_strm.next_in = (Bytef *)
 220                                         map_ptr(buf, offset, n);
 221                                 tx_strm.avail_in = n;
 222                                 nb -= n;
 223                                 offset += n;
 224                         }
 225                         if (tx_strm.avail_out == 0) {
 226                                 tx_strm.next_out = (Bytef *)(obuf + 2);
 227                                 tx_strm.avail_out = MAX_DATA_COUNT;
 228                                 if (flush != Z_NO_FLUSH) {
 229                                         /*
 230                                          * We left the last 4 bytes in the
 231                                          * buffer, in case they are the
 232                                          * last 4.  Move them to the front.
 233                                          */
 234                                         memcpy(tx_strm.next_out,
 235                                                obuf+MAX_DATA_COUNT-2, 4);
 236                                         tx_strm.next_out += 4;
 237                                         tx_strm.avail_out -= 4;
 238                                 }
 239                         }
 240                         if (nb == 0 && token != -2)
 241                                 flush = Z_SYNC_FLUSH;
 242                         r = deflate(&tx_strm, flush);
 243                         if (r != Z_OK) {
 244                                 rprintf(FERROR, "deflate returned %d\n", r);
 245                                 exit_cleanup(RERR_STREAMIO);
 246                         }
 247                         if (nb == 0 || tx_strm.avail_out == 0) {
 248                                 n = MAX_DATA_COUNT - tx_strm.avail_out;
 249                                 if (flush != Z_NO_FLUSH) {
 250                                         /*
 251                                          * We have to trim off the last 4
 252                                          * bytes of output when flushing
 253                                          * (they are just 0, 0, ff, ff).
 254                                          */
 255                                         n -= 4;
 256                                 }
 257                                 if (n > 0) {
 258                                         obuf[0] = DEFLATED_DATA + (n >> 8);
 259                                         obuf[1] = n;
 260                                         write_buf(f, obuf, n+2);
 261                                         if (write_batch) /* dw */
 262                                             write_batch_delta_file(obuf,n+2);
 263                                 }
 264                         }
 265                 } while (nb != 0 || tx_strm.avail_out == 0);
 266                 flush_pending = token == -2;
 267         }
 268
 269         if (token == -1) {
 270                 /* end of file - clean up */
 271                 write_byte(f, END_FLAG);
 272                 if (write_batch) { /* dw */
 273                     temp_byte = END_FLAG;
 274                     write_batch_delta_file((char *)&temp_byte,sizeof(temp_byte));
 275                 }
 276
 277         } else if (token != -2) {
 278                 /* add the data in the current block to the compressor's
 279                    history and hash table */
 280                 tx_strm.next_in = (Bytef *) map_ptr(buf, offset, toklen);
 281                 tx_strm.avail_in = toklen;
 282                 tx_strm.next_out = (Bytef *) obuf;
 283                 tx_strm.avail_out = MAX_DATA_COUNT;
 284                 r = deflate(&tx_strm, Z_INSERT_ONLY);
 285                 if (r != Z_OK || tx_strm.avail_in != 0) {
 286                         rprintf(FERROR, "deflate on token returned %d (%d bytes left)\n",
 287                                 r, tx_strm.avail_in);
 288                         exit_cleanup(RERR_STREAMIO);
 289                 }
 290         }
 291 }
 292
 293
 294 /* tells us what the receiver is in the middle of doing */
 295 static enum { r_init, r_idle, r_running, r_inflating, r_inflated } recv_state;
 296
 297 /* for inflating stuff */
 298 static z_stream rx_strm;
 299 static char *cbuf;
 300 static char *dbuf;
 301
 302 /* for decoding runs of tokens */
 303 static int rx_token;
 304 static int rx_run;
 305
 306 /* Receive a deflated token and inflate it */
 307 static int
 308 recv_deflated_token(int f, char **data)
 309 {
 310         int n, r, flag;
 311         static int init_done;
 312         static int saved_flag;
 313
 314         for (;;) {
 315                 switch (recv_state) {
 316                 case r_init:
 317                         if (!init_done) {
 318                                 rx_strm.next_out = NULL;
 319                                 rx_strm.zalloc = NULL;
 320                                 rx_strm.zfree = NULL;
 321                                 if (inflateInit2(&rx_strm, -15) != Z_OK) {
 322                                         rprintf(FERROR, "inflate init failed\n");
 323                                         exit_cleanup(RERR_STREAMIO);
 324                                 }
 325                                 if ((cbuf = malloc(MAX_DATA_COUNT)) == NULL
 326                                     || (dbuf = malloc(CHUNK_SIZE)) == NULL)
 327                                         out_of_memory("recv_deflated_token");
 328                                 init_done = 1;
 329                         } else {
 330                                 inflateReset(&rx_strm);
 331                         }
 332                         recv_state = r_idle;
 333                         rx_token = 0;
 334                         break;
 335
 336                 case r_idle:
 337                 case r_inflated:
 338                         if (saved_flag) {
 339                                 flag = saved_flag & 0xff;
 340                                 saved_flag = 0;
 341                         } else
 342                                 flag = read_byte(f);
 343                         if ((flag & 0xC0) == DEFLATED_DATA) {
 344                                 n = ((flag & 0x3f) << 8) + read_byte(f);
 345                                 read_buf(f, cbuf, n);
 346                                 rx_strm.next_in = (Bytef *)cbuf;
 347                                 rx_strm.avail_in = n;
 348                                 recv_state = r_inflating;
 349                                 break;
 350                         }
 351                         if (recv_state == r_inflated) {
 352                                 /* check previous inflated stuff ended correctly */
 353                                 rx_strm.avail_in = 0;
 354                                 rx_strm.next_out = (Bytef *)dbuf;
 355                                 rx_strm.avail_out = CHUNK_SIZE;
 356                                 r = inflate(&rx_strm, Z_SYNC_FLUSH);
 357                                 n = CHUNK_SIZE - rx_strm.avail_out;
 358                                 /*
 359                                  * Z_BUF_ERROR just means no progress was
 360                                  * made, i.e. the decompressor didn't have
 361                                  * any pending output for us.
 362                                  */
 363                                 if (r != Z_OK && r != Z_BUF_ERROR) {
 364                                         rprintf(FERROR, "inflate flush returned %d (%d bytes)\n",
 365                                                 r, n);
 366                                         exit_cleanup(RERR_STREAMIO);
 367                                 }
 368                                 if (n != 0 && r != Z_BUF_ERROR) {
 369                                         /* have to return some more data and
 370                                            save the flag for later. */
 371                                         saved_flag = flag + 0x10000;
 372                                         *data = dbuf;
 373                                         return n;
 374                                 }
 375                                 /*
 376                                  * At this point the decompressor should
 377                                  * be expecting to see the 0, 0, ff, ff bytes.
 378                                  */
 379                                 if (!inflateSyncPoint(&rx_strm)) {
 380                                         rprintf(FERROR, "decompressor lost sync!\n");
 381                                         exit_cleanup(RERR_STREAMIO);
 382                                 }
 383                                 rx_strm.avail_in = 4;
 384                                 rx_strm.next_in = (Bytef *)cbuf;
 385                                 cbuf[0] = cbuf[1] = 0;
 386                                 cbuf[2] = cbuf[3] = 0xff;
 387                                 inflate(&rx_strm, Z_SYNC_FLUSH);
 388                                 recv_state = r_idle;
 389                         }
 390                         if (flag == END_FLAG) {
 391                                 /* that's all folks */
 392                                 recv_state = r_init;
 393                                 return 0;
 394                         }
 395
 396                         /* here we have a token of some kind */
 397                         if (flag & TOKEN_REL) {
 398                                 rx_token += flag & 0x3f;
 399                                 flag >>= 6;
 400                         } else
 401                                 rx_token = read_int(f);
 402                         if (flag & 1) {
 403                                 rx_run = read_byte(f);
 404                                 rx_run += read_byte(f) << 8;
 405                                 recv_state = r_running;
 406                         }
 407                         return -1 - rx_token;
 408
 409                 case r_inflating:
 410                         rx_strm.next_out = (Bytef *)dbuf;
 411                         rx_strm.avail_out = CHUNK_SIZE;
 412                         r = inflate(&rx_strm, Z_NO_FLUSH);
 413                         n = CHUNK_SIZE - rx_strm.avail_out;
 414                         if (r != Z_OK) {
 415                                 rprintf(FERROR, "inflate returned %d (%d bytes)\n", r, n);
 416                                 exit_cleanup(RERR_STREAMIO);
 417                         }
 418                         if (rx_strm.avail_in == 0)
 419                                 recv_state = r_inflated;
 420                         if (n != 0) {
 421                                 *data = dbuf;
 422                                 return n;
 423                         }
 424                         break;
 425
 426                 case r_running:
 427                         ++rx_token;
 428                         if (--rx_run == 0)
 429                                 recv_state = r_idle;
 430                         return -1 - rx_token;
 431                 }
 432         }
 433 }
 434
 435 /*
 436  * put the data corresponding to a token that we've just returned
 437  * from recv_deflated_token into the decompressor's history buffer.
 438  */
 439 static void see_deflate_token(char *buf, int len)
 440 {
 441         int r, blklen;
 442         unsigned char hdr[5];
 443
 444         rx_strm.avail_in = 0;
 445         blklen = 0;
 446         hdr[0] = 0;
 447         do {
 448                 if (rx_strm.avail_in == 0 && len != 0) {
 449                         if (blklen == 0) {
 450                                 /* Give it a fake stored-block header. */
 451                                 rx_strm.next_in = (Bytef *)hdr;
 452                                 rx_strm.avail_in = 5;
 453                                 blklen = len;
 454                                 if (blklen > 0xffff)
 455                                         blklen = 0xffff;
 456                                 hdr[1] = blklen;
 457                                 hdr[2] = blklen >> 8;
 458                                 hdr[3] = ~hdr[1];
 459                                 hdr[4] = ~hdr[2];
 460                         } else {
 461                                 rx_strm.next_in = (Bytef *)buf;
 462                                 rx_strm.avail_in = blklen;
 463                                 len -= blklen;
 464                                 blklen = 0;
 465                         }
 466                 }
 467                 rx_strm.next_out = (Bytef *)dbuf;
 468                 rx_strm.avail_out = CHUNK_SIZE;
 469                 r = inflate(&rx_strm, Z_SYNC_FLUSH);
 470                 if (r != Z_OK) {
 471                         rprintf(FERROR, "inflate (token) returned %d\n", r);
 472                         exit_cleanup(RERR_STREAMIO);
 473                 }
 474         } while (len || rx_strm.avail_out == 0);
 475 }
 476
 477 /*
 478  * transmit a verbatim buffer of length n followed by a token
 479  * If token == -1 then we have reached EOF
 480  * If n == 0 then don't send a buffer
 481  */
 482 void send_token(int f,int token,struct map_struct *buf,OFF_T offset,
 483                 int n,int toklen)
 484 {
 485         if (!do_compression) {
 486                 simple_send_token(f,token,buf,offset,n);
 487         } else {
 488                 send_deflated_token(f, token, buf, offset, n, toklen);
 489         }
 490 }
 491
 492
 493 /*
 494  * receive a token or buffer from the other end. If the reurn value is >0 then
 495  * it is a data buffer of that length, and *data will point at the data.
 496  * if the return value is -i then it represents token i-1
 497  * if the return value is 0 then the end has been reached
 498  */
 499 int recv_token(int f,char **data)
 500 {
 501         int tok;
 502
 503         if (!do_compression) {
 504                 tok = simple_recv_token(f,data);
 505         } else {
 506                 tok = recv_deflated_token(f, data);
 507         }
 508         return tok;
 509 }
 510
 511 /*
 512  * look at the data corresponding to a token, if necessary
 513  */
 514 void see_token(char *data, int toklen)
 515 {
 516         if (do_compression)
 517                 see_deflate_token(data, toklen);
 518 }