token.c

   1 /*
   2  * Routines used by the file-transfer code.
   3  *
   4  * Copyright (C) 1996 Andrew Tridgell
   5  * Copyright (C) 1996 Paul Mackerras
   6  * Copyright (C) 2003-2007 Wayne Davison
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License along
  18  * with this program; if not, write to the Free Software Foundation, Inc.,
  19  * 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA.
  20  */
  21
  22 #include "rsync.h"
  23 #include "zlib/zlib.h"
  24
  25 extern int do_compression;
  26 extern int module_id;
  27 extern int def_compress_level;
  28
  29 static int compression_level, per_file_default_level;
  30
  31 /* determine the compression level based on a wildcard filename list */
  32 void set_compression(char *fname)
  33 {
  34         static char *match_list;
  35         char *s;
  36
  37         if (!do_compression)
  38                 return;
  39
  40         if (!match_list) {
  41                 char *t, *f = lp_dont_compress(module_id);
  42                 int len = strlen(f);
  43                 if (!(match_list = t = new_array(char, len + 2)))
  44                         out_of_memory("set_compression");
  45                 while (*f) {
  46                         if (*f == ' ') {
  47                                 f++;
  48                                 continue;
  49                         }
  50                         do {
  51                                 if (isUpper(f))
  52                                         *t++ = toLower(f);
  53                                 else
  54                                         *t++ = *f;
  55                         } while (*++f != ' ' && *f);
  56                         *t++ = '\0';
  57                 }
  58                 /* Optimize a match-string of "*". */
  59                 if (t - match_list == 2 && match_list[0] == '*') {
  60                         t = match_list;
  61                         per_file_default_level = 0;
  62                 } else
  63                         per_file_default_level = def_compress_level;
  64                 *t++ = '\0';
  65         }
  66
  67         compression_level = per_file_default_level;
  68
  69         if (!*match_list)
  70                 return;
  71
  72         if ((s = strrchr(fname, '/')) != NULL)
  73                 fname = s + 1;
  74
  75         for (s = match_list; *s; s += strlen(s) + 1) {
  76                 if (iwildmatch(s, fname)) {
  77                         compression_level = 0;
  78                         break;
  79                 }
  80         }
  81 }
  82
  83 /* non-compressing recv token */
  84 static int32 simple_recv_token(int f, char **data)
  85 {
  86         static int32 residue;
  87         static char *buf;
  88         int32 n;
  89
  90         if (!buf) {
  91                 buf = new_array(char, CHUNK_SIZE);
  92                 if (!buf)
  93                         out_of_memory("simple_recv_token");
  94         }
  95
  96         if (residue == 0) {
  97                 int32 i = read_int(f);
  98                 if (i <= 0)
  99                         return i;
 100                 residue = i;
 101         }
 102
 103         *data = buf;
 104         n = MIN(CHUNK_SIZE,residue);
 105         residue -= n;
 106         read_buf(f,buf,n);
 107         return n;
 108 }
 109
 110 /* non-compressing send token */
 111 static void simple_send_token(int f, int32 token, struct map_struct *buf,
 112                               OFF_T offset, int32 n)
 113 {
 114         if (n > 0) {
 115                 int32 len = 0;
 116                 while (len < n) {
 117                         int32 n1 = MIN(CHUNK_SIZE, n-len);
 118                         write_int(f, n1);
 119                         write_buf(f, map_ptr(buf, offset+len, n1), n1);
 120                         len += n1;
 121                 }
 122         }
 123         /* a -2 token means to send data only and no token */
 124         if (token != -2)
 125                 write_int(f, -(token+1));
 126 }
 127
 128 /* Flag bytes in compressed stream are encoded as follows: */
 129 #define END_FLAG        0       /* that's all folks */
 130 #define TOKEN_LONG      0x20    /* followed by 32-bit token number */
 131 #define TOKENRUN_LONG   0x21    /* ditto with 16-bit run count */
 132 #define DEFLATED_DATA   0x40    /* + 6-bit high len, then low len byte */
 133 #define TOKEN_REL       0x80    /* + 6-bit relative token number */
 134 #define TOKENRUN_REL    0xc0    /* ditto with 16-bit run count */
 135
 136 #define MAX_DATA_COUNT  16383   /* fit 14 bit count into 2 bytes with flags */
 137
 138 /* zlib.h says that if we want to be able to compress something in a single
 139  * call, avail_out must be at least 0.1% larger than avail_in plus 12 bytes.
 140  * We'll add in 0.1%+16, just to be safe (and we'll avoid floating point,
 141  * to ensure that this is a compile-time value). */
 142 #define AVAIL_OUT_SIZE(avail_in_size) ((avail_in_size)*1001/1000+16)
 143
 144 /* For coding runs of tokens */
 145 static int32 last_token = -1;
 146 static int32 run_start;
 147 static int32 last_run_end;
 148
 149 /* Deflation state */
 150 static z_stream tx_strm;
 151
 152 /* Output buffer */
 153 static char *obuf;
 154
 155 /* We want obuf to be able to hold both MAX_DATA_COUNT+2 bytes as well as
 156  * AVAIL_OUT_SIZE(CHUNK_SIZE) bytes, so make sure that it's large enough. */
 157 #if MAX_DATA_COUNT+2 > AVAIL_OUT_SIZE(CHUNK_SIZE)
 158 #define OBUF_SIZE       (MAX_DATA_COUNT+2)
 159 #else
 160 #define OBUF_SIZE       AVAIL_OUT_SIZE(CHUNK_SIZE)
 161 #endif
 162
 163 /* Send a deflated token */
 164 static void
 165 send_deflated_token(int f, int32 token, struct map_struct *buf, OFF_T offset,
 166                     int32 nb, int32 toklen)
 167 {
 168         int32 n, r;
 169         static int init_done, flush_pending;
 170
 171         if (last_token == -1) {
 172                 /* initialization */
 173                 if (!init_done) {
 174                         tx_strm.next_in = NULL;
 175                         tx_strm.zalloc = NULL;
 176                         tx_strm.zfree = NULL;
 177                         if (deflateInit2(&tx_strm, compression_level,
 178                                          Z_DEFLATED, -15, 8,
 179                                          Z_DEFAULT_STRATEGY) != Z_OK) {
 180                                 rprintf(FERROR, "compression init failed\n");
 181                                 exit_cleanup(RERR_STREAMIO);
 182                         }
 183                         if ((obuf = new_array(char, OBUF_SIZE)) == NULL)
 184                                 out_of_memory("send_deflated_token");
 185                         init_done = 1;
 186                 } else
 187                         deflateReset(&tx_strm);
 188                 last_run_end = 0;
 189                 run_start = token;
 190                 flush_pending = 0;
 191         } else if (last_token == -2) {
 192                 run_start = token;
 193         } else if (nb != 0 || token != last_token + 1
 194                    || token >= run_start + 65536) {
 195                 /* output previous run */
 196                 r = run_start - last_run_end;
 197                 n = last_token - run_start;
 198                 if (r >= 0 && r <= 63) {
 199                         write_byte(f, (n==0? TOKEN_REL: TOKENRUN_REL) + r);
 200                 } else {
 201                         write_byte(f, (n==0? TOKEN_LONG: TOKENRUN_LONG));
 202                         write_int(f, run_start);
 203                 }
 204                 if (n != 0) {
 205                         write_byte(f, n);
 206                         write_byte(f, n >> 8);
 207                 }
 208                 last_run_end = last_token;
 209                 run_start = token;
 210         }
 211
 212         last_token = token;
 213
 214         if (nb != 0 || flush_pending) {
 215                 /* deflate the data starting at offset */
 216                 int flush = Z_NO_FLUSH;
 217                 tx_strm.avail_in = 0;
 218                 tx_strm.avail_out = 0;
 219                 do {
 220                         if (tx_strm.avail_in == 0 && nb != 0) {
 221                                 /* give it some more input */
 222                                 n = MIN(nb, CHUNK_SIZE);
 223                                 tx_strm.next_in = (Bytef *)
 224                                         map_ptr(buf, offset, n);
 225                                 tx_strm.avail_in = n;
 226                                 nb -= n;
 227                                 offset += n;
 228                         }
 229                         if (tx_strm.avail_out == 0) {
 230                                 tx_strm.next_out = (Bytef *)(obuf + 2);
 231                                 tx_strm.avail_out = MAX_DATA_COUNT;
 232                                 if (flush != Z_NO_FLUSH) {
 233                                         /*
 234                                          * We left the last 4 bytes in the
 235                                          * buffer, in case they are the
 236                                          * last 4.  Move them to the front.
 237                                          */
 238                                         memcpy(tx_strm.next_out,
 239                                                obuf+MAX_DATA_COUNT-2, 4);
 240                                         tx_strm.next_out += 4;
 241                                         tx_strm.avail_out -= 4;
 242                                 }
 243                         }
 244                         if (nb == 0 && token != -2)
 245                                 flush = Z_SYNC_FLUSH;
 246                         r = deflate(&tx_strm, flush);
 247                         if (r != Z_OK) {
 248                                 rprintf(FERROR, "deflate returned %d\n", r);
 249                                 exit_cleanup(RERR_STREAMIO);
 250                         }
 251                         if (nb == 0 || tx_strm.avail_out == 0) {
 252                                 n = MAX_DATA_COUNT - tx_strm.avail_out;
 253                                 if (flush != Z_NO_FLUSH) {
 254                                         /*
 255                                          * We have to trim off the last 4
 256                                          * bytes of output when flushing
 257                                          * (they are just 0, 0, ff, ff).
 258                                          */
 259                                         n -= 4;
 260                                 }
 261                                 if (n > 0) {
 262                                         obuf[0] = DEFLATED_DATA + (n >> 8);
 263                                         obuf[1] = n;
 264                                         write_buf(f, obuf, n+2);
 265                                 }
 266                         }
 267                 } while (nb != 0 || tx_strm.avail_out == 0);
 268                 flush_pending = token == -2;
 269         }
 270
 271         if (token == -1) {
 272                 /* end of file - clean up */
 273                 write_byte(f, END_FLAG);
 274         } else if (token != -2) {
 275                 /* Add the data in the current block to the compressor's
 276                  * history and hash table. */
 277                 do {
 278                         /* Break up long sections in the same way that
 279                          * see_deflate_token() does. */
 280                         int32 n1 = toklen > 0xffff ? 0xffff : toklen;
 281                         toklen -= n1;
 282                         tx_strm.next_in = (Bytef *)map_ptr(buf, offset, n1);
 283                         tx_strm.avail_in = n1;
 284                         tx_strm.next_out = (Bytef *) obuf;
 285                         tx_strm.avail_out = AVAIL_OUT_SIZE(CHUNK_SIZE);
 286                         r = deflate(&tx_strm, Z_INSERT_ONLY);
 287                         if (r != Z_OK || tx_strm.avail_in != 0) {
 288                                 rprintf(FERROR, "deflate on token returned %d (%d bytes left)\n",
 289                                         r, tx_strm.avail_in);
 290                                 exit_cleanup(RERR_STREAMIO);
 291                         }
 292                 } while (toklen > 0);
 293         }
 294 }
 295
 296 /* tells us what the receiver is in the middle of doing */
 297 static enum { r_init, r_idle, r_running, r_inflating, r_inflated } recv_state;
 298
 299 /* for inflating stuff */
 300 static z_stream rx_strm;
 301 static char *cbuf;
 302 static char *dbuf;
 303
 304 /* for decoding runs of tokens */
 305 static int32 rx_token;
 306 static int32 rx_run;
 307
 308 /* Receive a deflated token and inflate it */
 309 static int32 recv_deflated_token(int f, char **data)
 310 {
 311         static int init_done;
 312         static int32 saved_flag;
 313         int32 n, flag;
 314         int r;
 315
 316         for (;;) {
 317                 switch (recv_state) {
 318                 case r_init:
 319                         if (!init_done) {
 320                                 rx_strm.next_out = NULL;
 321                                 rx_strm.zalloc = NULL;
 322                                 rx_strm.zfree = NULL;
 323                                 if (inflateInit2(&rx_strm, -15) != Z_OK) {
 324                                         rprintf(FERROR, "inflate init failed\n");
 325                                         exit_cleanup(RERR_STREAMIO);
 326                                 }
 327                                 if (!(cbuf = new_array(char, MAX_DATA_COUNT))
 328                                     || !(dbuf = new_array(char, AVAIL_OUT_SIZE(CHUNK_SIZE))))
 329                                         out_of_memory("recv_deflated_token");
 330                                 init_done = 1;
 331                         } else {
 332                                 inflateReset(&rx_strm);
 333                         }
 334                         recv_state = r_idle;
 335                         rx_token = 0;
 336                         break;
 337
 338                 case r_idle:
 339                 case r_inflated:
 340                         if (saved_flag) {
 341                                 flag = saved_flag & 0xff;
 342                                 saved_flag = 0;
 343                         } else
 344                                 flag = read_byte(f);
 345                         if ((flag & 0xC0) == DEFLATED_DATA) {
 346                                 n = ((flag & 0x3f) << 8) + read_byte(f);
 347                                 read_buf(f, cbuf, n);
 348                                 rx_strm.next_in = (Bytef *)cbuf;
 349                                 rx_strm.avail_in = n;
 350                                 recv_state = r_inflating;
 351                                 break;
 352                         }
 353                         if (recv_state == r_inflated) {
 354                                 /* check previous inflated stuff ended correctly */
 355                                 rx_strm.avail_in = 0;
 356                                 rx_strm.next_out = (Bytef *)dbuf;
 357                                 rx_strm.avail_out = AVAIL_OUT_SIZE(CHUNK_SIZE);
 358                                 r = inflate(&rx_strm, Z_SYNC_FLUSH);
 359                                 n = AVAIL_OUT_SIZE(CHUNK_SIZE) - rx_strm.avail_out;
 360                                 /*
 361                                  * Z_BUF_ERROR just means no progress was
 362                                  * made, i.e. the decompressor didn't have
 363                                  * any pending output for us.
 364                                  */
 365                                 if (r != Z_OK && r != Z_BUF_ERROR) {
 366                                         rprintf(FERROR, "inflate flush returned %d (%d bytes)\n",
 367                                                 r, n);
 368                                         exit_cleanup(RERR_STREAMIO);
 369                                 }
 370                                 if (n != 0 && r != Z_BUF_ERROR) {
 371                                         /* have to return some more data and
 372                                            save the flag for later. */
 373                                         saved_flag = flag + 0x10000;
 374                                         *data = dbuf;
 375                                         return n;
 376                                 }
 377                                 /*
 378                                  * At this point the decompressor should
 379                                  * be expecting to see the 0, 0, ff, ff bytes.
 380                                  */
 381                                 if (!inflateSyncPoint(&rx_strm)) {
 382                                         rprintf(FERROR, "decompressor lost sync!\n");
 383                                         exit_cleanup(RERR_STREAMIO);
 384                                 }
 385                                 rx_strm.avail_in = 4;
 386                                 rx_strm.next_in = (Bytef *)cbuf;
 387                                 cbuf[0] = cbuf[1] = 0;
 388                                 cbuf[2] = cbuf[3] = 0xff;
 389                                 inflate(&rx_strm, Z_SYNC_FLUSH);
 390                                 recv_state = r_idle;
 391                         }
 392                         if (flag == END_FLAG) {
 393                                 /* that's all folks */
 394                                 recv_state = r_init;
 395                                 return 0;
 396                         }
 397
 398                         /* here we have a token of some kind */
 399                         if (flag & TOKEN_REL) {
 400                                 rx_token += flag & 0x3f;
 401                                 flag >>= 6;
 402                         } else
 403                                 rx_token = read_int(f);
 404                         if (flag & 1) {
 405                                 rx_run = read_byte(f);
 406                                 rx_run += read_byte(f) << 8;
 407                                 recv_state = r_running;
 408                         }
 409                         return -1 - rx_token;
 410
 411                 case r_inflating:
 412                         rx_strm.next_out = (Bytef *)dbuf;
 413                         rx_strm.avail_out = AVAIL_OUT_SIZE(CHUNK_SIZE);
 414                         r = inflate(&rx_strm, Z_NO_FLUSH);
 415                         n = AVAIL_OUT_SIZE(CHUNK_SIZE) - rx_strm.avail_out;
 416                         if (r != Z_OK) {
 417                                 rprintf(FERROR, "inflate returned %d (%d bytes)\n", r, n);
 418                                 exit_cleanup(RERR_STREAMIO);
 419                         }
 420                         if (rx_strm.avail_in == 0)
 421                                 recv_state = r_inflated;
 422                         if (n != 0) {
 423                                 *data = dbuf;
 424                                 return n;
 425                         }
 426                         break;
 427
 428                 case r_running:
 429                         ++rx_token;
 430                         if (--rx_run == 0)
 431                                 recv_state = r_idle;
 432                         return -1 - rx_token;
 433                 }
 434         }
 435 }
 436
 437 /*
 438  * put the data corresponding to a token that we've just returned
 439  * from recv_deflated_token into the decompressor's history buffer.
 440  */
 441 static void see_deflate_token(char *buf, int32 len)
 442 {
 443         int r;
 444         int32 blklen;
 445         unsigned char hdr[5];
 446
 447         rx_strm.avail_in = 0;
 448         blklen = 0;
 449         hdr[0] = 0;
 450         do {
 451                 if (rx_strm.avail_in == 0 && len != 0) {
 452                         if (blklen == 0) {
 453                                 /* Give it a fake stored-block header. */
 454                                 rx_strm.next_in = (Bytef *)hdr;
 455                                 rx_strm.avail_in = 5;
 456                                 blklen = len;
 457                                 if (blklen > 0xffff)
 458                                         blklen = 0xffff;
 459                                 hdr[1] = blklen;
 460                                 hdr[2] = blklen >> 8;
 461                                 hdr[3] = ~hdr[1];
 462                                 hdr[4] = ~hdr[2];
 463                         } else {
 464                                 rx_strm.next_in = (Bytef *)buf;
 465                                 rx_strm.avail_in = blklen;
 466                                 len -= blklen;
 467                                 blklen = 0;
 468                         }
 469                 }
 470                 rx_strm.next_out = (Bytef *)dbuf;
 471                 rx_strm.avail_out = AVAIL_OUT_SIZE(CHUNK_SIZE);
 472                 r = inflate(&rx_strm, Z_SYNC_FLUSH);
 473                 if (r != Z_OK) {
 474                         rprintf(FERROR, "inflate (token) returned %d\n", r);
 475                         exit_cleanup(RERR_STREAMIO);
 476                 }
 477         } while (len || rx_strm.avail_out == 0);
 478 }
 479
 480 /**
 481  * Transmit a verbatim buffer of length @p n followed by a token.
 482  * If token == -1 then we have reached EOF
 483  * If n == 0 then don't send a buffer
 484  */
 485 void send_token(int f, int32 token, struct map_struct *buf, OFF_T offset,
 486                 int32 n, int32 toklen)
 487 {
 488         if (!do_compression)
 489                 simple_send_token(f, token, buf, offset, n);
 490         else
 491                 send_deflated_token(f, token, buf, offset, n, toklen);
 492 }
 493
 494 /*
 495  * receive a token or buffer from the other end. If the reurn value is >0 then
 496  * it is a data buffer of that length, and *data will point at the data.
 497  * if the return value is -i then it represents token i-1
 498  * if the return value is 0 then the end has been reached
 499  */
 500 int32 recv_token(int f, char **data)
 501 {
 502         int tok;
 503
 504         if (!do_compression) {
 505                 tok = simple_recv_token(f,data);
 506         } else {
 507                 tok = recv_deflated_token(f, data);
 508         }
 509         return tok;
 510 }
 511
 512 /*
 513  * look at the data corresponding to a token, if necessary
 514  */
 515 void see_token(char *data, int32 toklen)
 516 {
 517         if (do_compression)
 518                 see_deflate_token(data, toklen);
 519 }