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 static int obuf_size;
 141
 142 /* Send a deflated token */
 143 static void
 144 send_deflated_token(int f, int token,
 145                     struct map_struct *buf, OFF_T offset, int nb, int toklen)
 146 {
 147         int n, r;
 148         static int init_done, flush_pending;
 149         extern int write_batch;  /* dw */
 150         char temp_byte;   /* dw */
 151
 152         if (last_token == -1) {
 153                 /* initialization */
 154                 if (!init_done) {
 155                         tx_strm.next_in = NULL;
 156                         tx_strm.zalloc = NULL;
 157                         tx_strm.zfree = NULL;
 158                         if (deflateInit2(&tx_strm, compression_level,
 159                                          Z_DEFLATED, -15, 8,
 160                                          Z_DEFAULT_STRATEGY) != Z_OK) {
 161                                 rprintf(FERROR, "compression init failed\n");
 162                                 exit_cleanup(RERR_STREAMIO);
 163                         }
 164 #if MAX_DATA_COUNT+2 > CHUNK_SIZE+128 /* this shouldn't ever happen... */
 165                         obuf_size = MAX_DATA_COUNT+2;
 166 #else
 167                         obuf_size = CHUNK_SIZE+128;
 168 #endif
 169                         if ((obuf = malloc(obuf_size)) == NULL)
 170                                 out_of_memory("send_deflated_token");
 171                         init_done = 1;
 172                 } else
 173                         deflateReset(&tx_strm);
 174                 last_run_end = 0;
 175                 run_start = token;
 176                 flush_pending = 0;
 177
 178         } else if (last_token == -2) {
 179                 run_start = token;
 180
 181         } else if (nb != 0 || token != last_token + 1
 182                    || token >= run_start + 65536) {
 183                 /* output previous run */
 184                 r = run_start - last_run_end;
 185                 n = last_token - run_start;
 186                 if (r >= 0 && r <= 63) {
 187                         write_byte(f, (n==0? TOKEN_REL: TOKENRUN_REL) + r);
 188                         if (write_batch) { /* dw */
 189                             temp_byte = (char)( (n==0? TOKEN_REL: TOKENRUN_REL) + r);
 190                             write_batch_delta_file(&temp_byte,sizeof(char));
 191                         }
 192                 } else {
 193                         write_byte(f, (n==0? TOKEN_LONG: TOKENRUN_LONG));
 194                         write_int(f, run_start);
 195                         if (write_batch) { /* dw */
 196                             temp_byte = (char)(n==0? TOKEN_LONG: TOKENRUN_LONG);
 197                             write_batch_delta_file(&temp_byte,sizeof(temp_byte));
 198                             write_batch_delta_file((char *)&run_start,sizeof(run_start));
 199                         }
 200                 }
 201                 if (n != 0) {
 202                         write_byte(f, n);
 203                         write_byte(f, n >> 8);
 204                         if (write_batch) { /* dw */
 205                             write_batch_delta_file((char *)&n,sizeof(char));
 206                             temp_byte = (char) n >> 8;
 207                             write_batch_delta_file(&temp_byte,sizeof(temp_byte));
 208                         }
 209                 }
 210                 last_run_end = last_token;
 211                 run_start = token;
 212         }
 213
 214         last_token = token;
 215
 216         if (nb != 0 || flush_pending) {
 217                 /* deflate the data starting at offset */
 218                 int flush = Z_NO_FLUSH;
 219                 tx_strm.avail_in = 0;
 220                 tx_strm.avail_out = 0;
 221                 do {
 222                         if (tx_strm.avail_in == 0 && nb != 0) {
 223                                 /* give it some more input */
 224                                 n = MIN(nb, CHUNK_SIZE);
 225                                 tx_strm.next_in = (Bytef *)
 226                                         map_ptr(buf, offset, n);
 227                                 tx_strm.avail_in = n;
 228                                 nb -= n;
 229                                 offset += n;
 230                         }
 231                         if (tx_strm.avail_out == 0) {
 232                                 tx_strm.next_out = (Bytef *)(obuf + 2);
 233                                 tx_strm.avail_out = MAX_DATA_COUNT;
 234                                 if (flush != Z_NO_FLUSH) {
 235                                         /*
 236                                          * We left the last 4 bytes in the
 237                                          * buffer, in case they are the
 238                                          * last 4.  Move them to the front.
 239                                          */
 240                                         memcpy(tx_strm.next_out,
 241                                                obuf+MAX_DATA_COUNT-2, 4);
 242                                         tx_strm.next_out += 4;
 243                                         tx_strm.avail_out -= 4;
 244                                 }
 245                         }
 246                         if (nb == 0 && token != -2)
 247                                 flush = Z_SYNC_FLUSH;
 248                         r = deflate(&tx_strm, flush);
 249                         if (r != Z_OK) {
 250                                 rprintf(FERROR, "deflate returned %d\n", r);
 251                                 exit_cleanup(RERR_STREAMIO);
 252                         }
 253                         if (nb == 0 || tx_strm.avail_out == 0) {
 254                                 n = MAX_DATA_COUNT - tx_strm.avail_out;
 255                                 if (flush != Z_NO_FLUSH) {
 256                                         /*
 257                                          * We have to trim off the last 4
 258                                          * bytes of output when flushing
 259                                          * (they are just 0, 0, ff, ff).
 260                                          */
 261                                         n -= 4;
 262                                 }
 263                                 if (n > 0) {
 264                                         obuf[0] = DEFLATED_DATA + (n >> 8);
 265                                         obuf[1] = n;
 266                                         write_buf(f, obuf, n+2);
 267                                         if (write_batch) /* dw */
 268                                             write_batch_delta_file(obuf,n+2);
 269                                 }
 270                         }
 271                 } while (nb != 0 || tx_strm.avail_out == 0);
 272                 flush_pending = token == -2;
 273         }
 274
 275         if (token == -1) {
 276                 /* end of file - clean up */
 277                 write_byte(f, END_FLAG);
 278                 if (write_batch) { /* dw */
 279                     temp_byte = END_FLAG;
 280                     write_batch_delta_file((char *)&temp_byte,sizeof(temp_byte));
 281                 }
 282
 283         } else if (token != -2) {
 284                 /* add the data in the current block to the compressor's
 285                    history and hash table */
 286                 tx_strm.next_in = (Bytef *) map_ptr(buf, offset, toklen);
 287                 tx_strm.avail_in = toklen;
 288                 tx_strm.next_out = (Bytef *) obuf;
 289                 tx_strm.avail_out = obuf_size;
 290                 r = deflate(&tx_strm, Z_INSERT_ONLY);
 291                 if (r != Z_OK || tx_strm.avail_in != 0) {
 292                         rprintf(FERROR, "deflate on token returned %d (%d bytes left)\n",
 293                                 r, tx_strm.avail_in);
 294                         exit_cleanup(RERR_STREAMIO);
 295                 }
 296         }
 297 }
 298
 299
 300 /* tells us what the receiver is in the middle of doing */
 301 static enum { r_init, r_idle, r_running, r_inflating, r_inflated } recv_state;
 302
 303 /* for inflating stuff */
 304 static z_stream rx_strm;
 305 static char *cbuf;
 306 static char *dbuf;
 307
 308 /* for decoding runs of tokens */
 309 static int rx_token;
 310 static int rx_run;
 311
 312 /* Receive a deflated token and inflate it */
 313 static int
 314 recv_deflated_token(int f, char **data)
 315 {
 316         int n, r, flag;
 317         static int init_done;
 318         static int saved_flag;
 319
 320         for (;;) {
 321                 switch (recv_state) {
 322                 case r_init:
 323                         if (!init_done) {
 324                                 rx_strm.next_out = NULL;
 325                                 rx_strm.zalloc = NULL;
 326                                 rx_strm.zfree = NULL;
 327                                 if (inflateInit2(&rx_strm, -15) != Z_OK) {
 328                                         rprintf(FERROR, "inflate init failed\n");
 329                                         exit_cleanup(RERR_STREAMIO);
 330                                 }
 331                                 if ((cbuf = malloc(MAX_DATA_COUNT)) == NULL
 332                                     || (dbuf = malloc(CHUNK_SIZE)) == NULL)
 333                                         out_of_memory("recv_deflated_token");
 334                                 init_done = 1;
 335                         } else {
 336                                 inflateReset(&rx_strm);
 337                         }
 338                         recv_state = r_idle;
 339                         rx_token = 0;
 340                         break;
 341
 342                 case r_idle:
 343                 case r_inflated:
 344                         if (saved_flag) {
 345                                 flag = saved_flag & 0xff;
 346                                 saved_flag = 0;
 347                         } else
 348                                 flag = read_byte(f);
 349                         if ((flag & 0xC0) == DEFLATED_DATA) {
 350                                 n = ((flag & 0x3f) << 8) + read_byte(f);
 351                                 read_buf(f, cbuf, n);
 352                                 rx_strm.next_in = (Bytef *)cbuf;
 353                                 rx_strm.avail_in = n;
 354                                 recv_state = r_inflating;
 355                                 break;
 356                         }
 357                         if (recv_state == r_inflated) {
 358                                 /* check previous inflated stuff ended correctly */
 359                                 rx_strm.avail_in = 0;
 360                                 rx_strm.next_out = (Bytef *)dbuf;
 361                                 rx_strm.avail_out = CHUNK_SIZE;
 362                                 r = inflate(&rx_strm, Z_SYNC_FLUSH);
 363                                 n = CHUNK_SIZE - rx_strm.avail_out;
 364                                 /*
 365                                  * Z_BUF_ERROR just means no progress was
 366                                  * made, i.e. the decompressor didn't have
 367                                  * any pending output for us.
 368                                  */
 369                                 if (r != Z_OK && r != Z_BUF_ERROR) {
 370                                         rprintf(FERROR, "inflate flush returned %d (%d bytes)\n",
 371                                                 r, n);
 372                                         exit_cleanup(RERR_STREAMIO);
 373                                 }
 374                                 if (n != 0 && r != Z_BUF_ERROR) {
 375                                         /* have to return some more data and
 376                                            save the flag for later. */
 377                                         saved_flag = flag + 0x10000;
 378                                         *data = dbuf;
 379                                         return n;
 380                                 }
 381                                 /*
 382                                  * At this point the decompressor should
 383                                  * be expecting to see the 0, 0, ff, ff bytes.
 384                                  */
 385                                 if (!inflateSyncPoint(&rx_strm)) {
 386                                         rprintf(FERROR, "decompressor lost sync!\n");
 387                                         exit_cleanup(RERR_STREAMIO);
 388                                 }
 389                                 rx_strm.avail_in = 4;
 390                                 rx_strm.next_in = (Bytef *)cbuf;
 391                                 cbuf[0] = cbuf[1] = 0;
 392                                 cbuf[2] = cbuf[3] = 0xff;
 393                                 inflate(&rx_strm, Z_SYNC_FLUSH);
 394                                 recv_state = r_idle;
 395                         }
 396                         if (flag == END_FLAG) {
 397                                 /* that's all folks */
 398                                 recv_state = r_init;
 399                                 return 0;
 400                         }
 401
 402                         /* here we have a token of some kind */
 403                         if (flag & TOKEN_REL) {
 404                                 rx_token += flag & 0x3f;
 405                                 flag >>= 6;
 406                         } else
 407                                 rx_token = read_int(f);
 408                         if (flag & 1) {
 409                                 rx_run = read_byte(f);
 410                                 rx_run += read_byte(f) << 8;
 411                                 recv_state = r_running;
 412                         }
 413                         return -1 - rx_token;
 414
 415                 case r_inflating:
 416                         rx_strm.next_out = (Bytef *)dbuf;
 417                         rx_strm.avail_out = CHUNK_SIZE;
 418                         r = inflate(&rx_strm, Z_NO_FLUSH);
 419                         n = CHUNK_SIZE - rx_strm.avail_out;
 420                         if (r != Z_OK) {
 421                                 rprintf(FERROR, "inflate returned %d (%d bytes)\n", r, n);
 422                                 exit_cleanup(RERR_STREAMIO);
 423                         }
 424                         if (rx_strm.avail_in == 0)
 425                                 recv_state = r_inflated;
 426                         if (n != 0) {
 427                                 *data = dbuf;
 428                                 return n;
 429                         }
 430                         break;
 431
 432                 case r_running:
 433                         ++rx_token;
 434                         if (--rx_run == 0)
 435                                 recv_state = r_idle;
 436                         return -1 - rx_token;
 437                 }
 438         }
 439 }
 440
 441 /*
 442  * put the data corresponding to a token that we've just returned
 443  * from recv_deflated_token into the decompressor's history buffer.
 444  */
 445 static void see_deflate_token(char *buf, int len)
 446 {
 447         int r, blklen;
 448         unsigned char hdr[5];
 449
 450         rx_strm.avail_in = 0;
 451         blklen = 0;
 452         hdr[0] = 0;
 453         do {
 454                 if (rx_strm.avail_in == 0 && len != 0) {
 455                         if (blklen == 0) {
 456                                 /* Give it a fake stored-block header. */
 457                                 rx_strm.next_in = (Bytef *)hdr;
 458                                 rx_strm.avail_in = 5;
 459                                 blklen = len;
 460                                 if (blklen > 0xffff)
 461                                         blklen = 0xffff;
 462                                 hdr[1] = blklen;
 463                                 hdr[2] = blklen >> 8;
 464                                 hdr[3] = ~hdr[1];
 465                                 hdr[4] = ~hdr[2];
 466                         } else {
 467                                 rx_strm.next_in = (Bytef *)buf;
 468                                 rx_strm.avail_in = blklen;
 469                                 len -= blklen;
 470                                 blklen = 0;
 471                         }
 472                 }
 473                 rx_strm.next_out = (Bytef *)dbuf;
 474                 rx_strm.avail_out = CHUNK_SIZE;
 475                 r = inflate(&rx_strm, Z_SYNC_FLUSH);
 476                 if (r != Z_OK) {
 477                         rprintf(FERROR, "inflate (token) returned %d\n", r);
 478                         exit_cleanup(RERR_STREAMIO);
 479                 }
 480         } while (len || rx_strm.avail_out == 0);
 481 }
 482
 483 /**
 484  * Transmit a verbatim buffer of length @p n followed by a token.
 485  * If token == -1 then we have reached EOF
 486  * If n == 0 then don't send a buffer
 487  */
 488 void send_token(int f,int token,struct map_struct *buf,OFF_T offset,
 489                 int n,int toklen)
 490 {
 491         if (!do_compression) {
 492                 simple_send_token(f,token,buf,offset,n);
 493         } else {
 494                 send_deflated_token(f, token, buf, offset, n, toklen);
 495         }
 496 }
 497
 498
 499 /*
 500  * receive a token or buffer from the other end. If the reurn value is >0 then
 501  * it is a data buffer of that length, and *data will point at the data.
 502  * if the return value is -i then it represents token i-1
 503  * if the return value is 0 then the end has been reached
 504  */
 505 int recv_token(int f,char **data)
 506 {
 507         int tok;
 508
 509         if (!do_compression) {
 510                 tok = simple_recv_token(f,data);
 511         } else {
 512                 tok = recv_deflated_token(f, data);
 513         }
 514         return tok;
 515 }
 516
 517 /*
 518  * look at the data corresponding to a token, if necessary
 519  */
 520 void see_token(char *data, int toklen)
 521 {
 522         if (do_compression)
 523                 see_deflate_token(data, toklen);
 524 }