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