?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
Preparing for release of 3.1.0pre1
[rsync.git] / token.c
blob953db783ea45d9aa2cf73e330535b79bccfcc596
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) 2003-2013 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 as published by
10 * the Free Software Foundation; either version 3 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License along
19 * with this program; if not, visit the http://fsf.org website.
20 */
21
22 #include "rsync.h"
23 #include "itypes.h"
24 #include <zlib.h>
25
26 #ifndef Z_INSERT_ONLY
27 #define Z_INSERT_ONLY Z_SYNC_FLUSH
28 #endif
29
30 extern int do_compression;
31 extern int protocol_version;
32 extern int module_id;
33 extern int def_compress_level;
34 extern char *skip_compress;
35
36 static int compression_level, per_file_default_level;
37
38 struct suffix_tree {
39 struct suffix_tree *sibling;
40 struct suffix_tree *child;
41 char letter, word_end;
42 };
43
44 static char *match_list;
45 static struct suffix_tree *suftree;
46
47 static void add_suffix(struct suffix_tree **prior, char ltr, const char *str)
48 {
49 struct suffix_tree *node, *newnode;
50
51 if (ltr == '[') {
52 const char *after = strchr(str, ']');
53 /* Treat "[foo" and "[]" as having a literal '['. */
54 if (after && after++ != str+1) {
55 while ((ltr = *str++) != ']')
56 add_suffix(prior, ltr, after);
57 return;
58 }
59 }
60
61 for (node = *prior; node; prior = &node->sibling, node = node->sibling) {
62 if (node->letter == ltr) {
63 if (*str)
64 add_suffix(&node->child, *str, str+1);
65 else
66 node->word_end = 1;
67 return;
68 }
69 if (node->letter > ltr)
70 break;
71 }
72 if (!(newnode = new(struct suffix_tree)))
73 out_of_memory("add_suffix");
74 newnode->sibling = node;
75 newnode->child = NULL;
76 newnode->letter = ltr;
77 *prior = newnode;
78 if (*str) {
79 add_suffix(&newnode->child, *str, str+1);
80 newnode->word_end = 0;
81 } else
82 newnode->word_end = 1;
83 }
84
85 static void add_nocompress_suffixes(const char *str)
86 {
87 char *buf, *t;
88 const char *f = str;
89
90 if (!(buf = new_array(char, strlen(f) + 1)))
91 out_of_memory("add_nocompress_suffixes");
92
93 while (*f) {
94 if (*f == '/') {
95 f++;
96 continue;
97 }
98
99 t = buf;
100 do {
101 if (isUpper(f))
102 *t++ = toLower(f);
103 else
104 *t++ = *f;
105 } while (*++f != '/' && *f);
106 *t++ = '\0';
107
108 add_suffix(&suftree, *buf, buf+1);
109 }
110
111 free(buf);
112 }
113
114 static void init_set_compression(void)
115 {
116 const char *f;
117 char *t, *start;
118
119 if (skip_compress)
120 add_nocompress_suffixes(skip_compress);
121
122 /* A non-daemon transfer skips the default suffix list if the
123 * user specified --skip-compress. */
124 if (skip_compress && module_id < 0)
125 f = "";
126 else
127 f = lp_dont_compress(module_id);
128
129 if (!(match_list = t = new_array(char, strlen(f) + 2)))
130 out_of_memory("set_compression");
131
132 per_file_default_level = def_compress_level;
133
134 while (*f) {
135 if (*f == ' ') {
136 f++;
137 continue;
138 }
139
140 start = t;
141 do {
142 if (isUpper(f))
143 *t++ = toLower(f);
144 else
145 *t++ = *f;
146 } while (*++f != ' ' && *f);
147 *t++ = '\0';
148
149 if (t - start == 1+1 && *start == '*') {
150 /* Optimize a match-string of "*". */
151 *match_list = '\0';
152 suftree = NULL;
153 per_file_default_level = 0;
154 break;
155 }
156
157 /* Move *.foo items into the stuffix tree. */
158 if (*start == '*' && start[1] == '.' && start[2]
159 && !strpbrk(start+2, ".?*")) {
160 add_suffix(&suftree, start[2], start+3);
161 t = start;
162 }
163 }
164 *t++ = '\0';
165 }
166
167 /* determine the compression level based on a wildcard filename list */
168 void set_compression(const char *fname)
169 {
170 const struct suffix_tree *node;
171 const char *s;
172 char ltr;
173
174 if (!do_compression)
175 return;
176
177 if (!match_list)
178 init_set_compression();
179
180 compression_level = per_file_default_level;
181
182 if (!*match_list && !suftree)
183 return;
184
185 if ((s = strrchr(fname, '/')) != NULL)
186 fname = s + 1;
187
188 for (s = match_list; *s; s += strlen(s) + 1) {
189 if (iwildmatch(s, fname)) {
190 compression_level = 0;
191 return;
192 }
193 }
194
195 if (!(node = suftree) || !(s = strrchr(fname, '.'))
196 || s == fname || !(ltr = *++s))
197 return;
198
199 while (1) {
200 if (isUpper(&ltr))
201 ltr = toLower(&ltr);
202 while (node->letter != ltr) {
203 if (node->letter > ltr)
204 return;
205 if (!(node = node->sibling))
206 return;
207 }
208 if ((ltr = *++s) == '\0') {
209 if (node->word_end)
210 compression_level = 0;
211 return;
212 }
213 if (!(node = node->child))
214 return;
215 }
216 }
217
218 /* non-compressing recv token */
219 static int32 simple_recv_token(int f, char **data)
220 {
221 static int32 residue;
222 static char *buf;
223 int32 n;
224
225 if (!buf) {
226 buf = new_array(char, CHUNK_SIZE);
227 if (!buf)
228 out_of_memory("simple_recv_token");
229 }
230
231 if (residue == 0) {
232 int32 i = read_int(f);
233 if (i <= 0)
234 return i;
235 residue = i;
236 }
237
238 *data = buf;
239 n = MIN(CHUNK_SIZE,residue);
240 residue -= n;
241 read_buf(f,buf,n);
242 return n;
243 }
244
245 /* non-compressing send token */
246 static void simple_send_token(int f, int32 token, struct map_struct *buf,
247 OFF_T offset, int32 n)
248 {
249 if (n > 0) {
250 int32 len = 0;
251 while (len < n) {
252 int32 n1 = MIN(CHUNK_SIZE, n-len);
253 write_int(f, n1);
254 write_buf(f, map_ptr(buf, offset+len, n1), n1);
255 len += n1;
256 }
257 }
258 /* a -2 token means to send data only and no token */
259 if (token != -2)
260 write_int(f, -(token+1));
261 }
262
263 /* Flag bytes in compressed stream are encoded as follows: */
264 #define END_FLAG 0 /* that's all folks */
265 #define TOKEN_LONG 0x20 /* followed by 32-bit token number */
266 #define TOKENRUN_LONG 0x21 /* ditto with 16-bit run count */
267 #define DEFLATED_DATA 0x40 /* + 6-bit high len, then low len byte */
268 #define TOKEN_REL 0x80 /* + 6-bit relative token number */
269 #define TOKENRUN_REL 0xc0 /* ditto with 16-bit run count */
270
271 #define MAX_DATA_COUNT 16383 /* fit 14 bit count into 2 bytes with flags */
272
273 /* zlib.h says that if we want to be able to compress something in a single
274 * call, avail_out must be at least 0.1% larger than avail_in plus 12 bytes.
275 * We'll add in 0.1%+16, just to be safe (and we'll avoid floating point,
276 * to ensure that this is a compile-time value). */
277 #define AVAIL_OUT_SIZE(avail_in_size) ((avail_in_size)*1001/1000+16)
278
279 /* For coding runs of tokens */
280 static int32 last_token = -1;
281 static int32 run_start;
282 static int32 last_run_end;
283
284 /* Deflation state */
285 static z_stream tx_strm;
286
287 /* Output buffer */
288 static char *obuf;
289
290 /* We want obuf to be able to hold both MAX_DATA_COUNT+2 bytes as well as
291 * AVAIL_OUT_SIZE(CHUNK_SIZE) bytes, so make sure that it's large enough. */
292 #if MAX_DATA_COUNT+2 > AVAIL_OUT_SIZE(CHUNK_SIZE)
293 #define OBUF_SIZE (MAX_DATA_COUNT+2)
294 #else
295 #define OBUF_SIZE AVAIL_OUT_SIZE(CHUNK_SIZE)
296 #endif
297
298 /* Send a deflated token */
299 static void
300 send_deflated_token(int f, int32 token, struct map_struct *buf, OFF_T offset,
301 int32 nb, int32 toklen)
302 {
303 int32 n, r;
304 static int init_done, flush_pending;
305
306 if (last_token == -1) {
307 /* initialization */
308 if (!init_done) {
309 tx_strm.next_in = NULL;
310 tx_strm.zalloc = NULL;
311 tx_strm.zfree = NULL;
312 if (deflateInit2(&tx_strm, compression_level,
313 Z_DEFLATED, -15, 8,
314 Z_DEFAULT_STRATEGY) != Z_OK) {
315 rprintf(FERROR, "compression init failed\n");
316 exit_cleanup(RERR_PROTOCOL);
317 }
318 if ((obuf = new_array(char, OBUF_SIZE)) == NULL)
319 out_of_memory("send_deflated_token");
320 init_done = 1;
321 } else
322 deflateReset(&tx_strm);
323 last_run_end = 0;
324 run_start = token;
325 flush_pending = 0;
326 } else if (last_token == -2) {
327 run_start = token;
328 } else if (nb != 0 || token != last_token + 1
329 || token >= run_start + 65536) {
330 /* output previous run */
331 r = run_start - last_run_end;
332 n = last_token - run_start;
333 if (r >= 0 && r <= 63) {
334 write_byte(f, (n==0? TOKEN_REL: TOKENRUN_REL) + r);
335 } else {
336 write_byte(f, (n==0? TOKEN_LONG: TOKENRUN_LONG));
337 write_int(f, run_start);
338 }
339 if (n != 0) {
340 write_byte(f, n);
341 write_byte(f, n >> 8);
342 }
343 last_run_end = last_token;
344 run_start = token;
345 }
346
347 last_token = token;
348
349 if (nb != 0 || flush_pending) {
350 /* deflate the data starting at offset */
351 int flush = Z_NO_FLUSH;
352 tx_strm.avail_in = 0;
353 tx_strm.avail_out = 0;
354 do {
355 if (tx_strm.avail_in == 0 && nb != 0) {
356 /* give it some more input */
357 n = MIN(nb, CHUNK_SIZE);
358 tx_strm.next_in = (Bytef *)
359 map_ptr(buf, offset, n);
360 tx_strm.avail_in = n;
361 nb -= n;
362 offset += n;
363 }
364 if (tx_strm.avail_out == 0) {
365 tx_strm.next_out = (Bytef *)(obuf + 2);
366 tx_strm.avail_out = MAX_DATA_COUNT;
367 if (flush != Z_NO_FLUSH) {
368 /*
369 * We left the last 4 bytes in the
370 * buffer, in case they are the
371 * last 4. Move them to the front.
372 */
373 memcpy(tx_strm.next_out,
374 obuf+MAX_DATA_COUNT-2, 4);
375 tx_strm.next_out += 4;
376 tx_strm.avail_out -= 4;
377 }
378 }
379 if (nb == 0 && token != -2)
380 flush = Z_SYNC_FLUSH;
381 r = deflate(&tx_strm, flush);
382 if (r != Z_OK) {
383 rprintf(FERROR, "deflate returned %d\n", r);
384 exit_cleanup(RERR_STREAMIO);
385 }
386 if (nb == 0 || tx_strm.avail_out == 0) {
387 n = MAX_DATA_COUNT - tx_strm.avail_out;
388 if (flush != Z_NO_FLUSH) {
389 /*
390 * We have to trim off the last 4
391 * bytes of output when flushing
392 * (they are just 0, 0, ff, ff).
393 */
394 n -= 4;
395 }
396 if (n > 0) {
397 obuf[0] = DEFLATED_DATA + (n >> 8);
398 obuf[1] = n;
399 write_buf(f, obuf, n+2);
400 }
401 }
402 } while (nb != 0 || tx_strm.avail_out == 0);
403 flush_pending = token == -2;
404 }
405
406 if (token == -1) {
407 /* end of file - clean up */
408 write_byte(f, END_FLAG);
409 } else if (token != -2) {
410 /* Add the data in the current block to the compressor's
411 * history and hash table. */
412 do {
413 /* Break up long sections in the same way that
414 * see_deflate_token() does. */
415 int32 n1 = toklen > 0xffff ? 0xffff : toklen;
416 toklen -= n1;
417 tx_strm.next_in = (Bytef *)map_ptr(buf, offset, n1);
418 tx_strm.avail_in = n1;
419 if (protocol_version >= 31) /* Newer protocols avoid a data-duplicating bug */
420 offset += n1;
421 do {
422 tx_strm.next_out = (Bytef *) obuf;
423 tx_strm.avail_out = AVAIL_OUT_SIZE(CHUNK_SIZE);
424 r = deflate(&tx_strm, Z_INSERT_ONLY);
425 if (r != Z_OK) {
426 rprintf(FERROR, "deflate on token returned %d (%d bytes left)\n",
427 r, tx_strm.avail_in);
428 exit_cleanup(RERR_STREAMIO);
429 }
430 } while (tx_strm.avail_in != 0);
431 } while (toklen > 0);
432 }
433 }
434
435 /* tells us what the receiver is in the middle of doing */
436 static enum { r_init, r_idle, r_running, r_inflating, r_inflated } recv_state;
437
438 /* for inflating stuff */
439 static z_stream rx_strm;
440 static char *cbuf;
441 static char *dbuf;
442
443 /* for decoding runs of tokens */
444 static int32 rx_token;
445 static int32 rx_run;
446
447 /* Receive a deflated token and inflate it */
448 static int32 recv_deflated_token(int f, char **data)
449 {
450 static int init_done;
451 static int32 saved_flag;
452 int32 n, flag;
453 int r;
454
455 for (;;) {
456 switch (recv_state) {
457 case r_init:
458 if (!init_done) {
459 rx_strm.next_out = NULL;
460 rx_strm.zalloc = NULL;
461 rx_strm.zfree = NULL;
462 if (inflateInit2(&rx_strm, -15) != Z_OK) {
463 rprintf(FERROR, "inflate init failed\n");
464 exit_cleanup(RERR_PROTOCOL);
465 }
466 if (!(cbuf = new_array(char, MAX_DATA_COUNT))
467 || !(dbuf = new_array(char, AVAIL_OUT_SIZE(CHUNK_SIZE))))
468 out_of_memory("recv_deflated_token");
469 init_done = 1;
470 } else {
471 inflateReset(&rx_strm);
472 }
473 recv_state = r_idle;
474 rx_token = 0;
475 break;
476
477 case r_idle:
478 case r_inflated:
479 if (saved_flag) {
480 flag = saved_flag & 0xff;
481 saved_flag = 0;
482 } else
483 flag = read_byte(f);
484 if ((flag & 0xC0) == DEFLATED_DATA) {
485 n = ((flag & 0x3f) << 8) + read_byte(f);
486 read_buf(f, cbuf, n);
487 rx_strm.next_in = (Bytef *)cbuf;
488 rx_strm.avail_in = n;
489 recv_state = r_inflating;
490 break;
491 }
492 if (recv_state == r_inflated) {
493 /* check previous inflated stuff ended correctly */
494 rx_strm.avail_in = 0;
495 rx_strm.next_out = (Bytef *)dbuf;
496 rx_strm.avail_out = AVAIL_OUT_SIZE(CHUNK_SIZE);
497 r = inflate(&rx_strm, Z_SYNC_FLUSH);
498 n = AVAIL_OUT_SIZE(CHUNK_SIZE) - rx_strm.avail_out;
499 /*
500 * Z_BUF_ERROR just means no progress was
501 * made, i.e. the decompressor didn't have
502 * any pending output for us.
503 */
504 if (r != Z_OK && r != Z_BUF_ERROR) {
505 rprintf(FERROR, "inflate flush returned %d (%d bytes)\n",
506 r, n);
507 exit_cleanup(RERR_STREAMIO);
508 }
509 if (n != 0 && r != Z_BUF_ERROR) {
510 /* have to return some more data and
511 save the flag for later. */
512 saved_flag = flag + 0x10000;
513 *data = dbuf;
514 return n;
515 }
516 /*
517 * At this point the decompressor should
518 * be expecting to see the 0, 0, ff, ff bytes.
519 */
520 if (!inflateSyncPoint(&rx_strm)) {
521 rprintf(FERROR, "decompressor lost sync!\n");
522 exit_cleanup(RERR_STREAMIO);
523 }
524 rx_strm.avail_in = 4;
525 rx_strm.next_in = (Bytef *)cbuf;
526 cbuf[0] = cbuf[1] = 0;
527 cbuf[2] = cbuf[3] = 0xff;
528 inflate(&rx_strm, Z_SYNC_FLUSH);
529 recv_state = r_idle;
530 }
531 if (flag == END_FLAG) {
532 /* that's all folks */
533 recv_state = r_init;
534 return 0;
535 }
536
537 /* here we have a token of some kind */
538 if (flag & TOKEN_REL) {
539 rx_token += flag & 0x3f;
540 flag >>= 6;
541 } else
542 rx_token = read_int(f);
543 if (flag & 1) {
544 rx_run = read_byte(f);
545 rx_run += read_byte(f) << 8;
546 recv_state = r_running;
547 }
548 return -1 - rx_token;
549
550 case r_inflating:
551 rx_strm.next_out = (Bytef *)dbuf;
552 rx_strm.avail_out = AVAIL_OUT_SIZE(CHUNK_SIZE);
553 r = inflate(&rx_strm, Z_NO_FLUSH);
554 n = AVAIL_OUT_SIZE(CHUNK_SIZE) - rx_strm.avail_out;
555 if (r != Z_OK) {
556 rprintf(FERROR, "inflate returned %d (%d bytes)\n", r, n);
557 exit_cleanup(RERR_STREAMIO);
558 }
559 if (rx_strm.avail_in == 0)
560 recv_state = r_inflated;
561 if (n != 0) {
562 *data = dbuf;
563 return n;
564 }
565 break;
566
567 case r_running:
568 ++rx_token;
569 if (--rx_run == 0)
570 recv_state = r_idle;
571 return -1 - rx_token;
572 }
573 }
574 }
575
576 /*
577 * put the data corresponding to a token that we've just returned
578 * from recv_deflated_token into the decompressor's history buffer.
579 */
580 static void see_deflate_token(char *buf, int32 len)
581 {
582 int r;
583 int32 blklen;
584 unsigned char hdr[5];
585
586 rx_strm.avail_in = 0;
587 blklen = 0;
588 hdr[0] = 0;
589 do {
590 if (rx_strm.avail_in == 0 && len != 0) {
591 if (blklen == 0) {
592 /* Give it a fake stored-block header. */
593 rx_strm.next_in = (Bytef *)hdr;
594 rx_strm.avail_in = 5;
595 blklen = len;
596 if (blklen > 0xffff)
597 blklen = 0xffff;
598 hdr[1] = blklen;
599 hdr[2] = blklen >> 8;
600 hdr[3] = ~hdr[1];
601 hdr[4] = ~hdr[2];
602 } else {
603 rx_strm.next_in = (Bytef *)buf;
604 rx_strm.avail_in = blklen;
605 if (protocol_version >= 31) /* Newer protocols avoid a data-duplicating bug */
606 buf += blklen;
607 len -= blklen;
608 blklen = 0;
609 }
610 }
611 rx_strm.next_out = (Bytef *)dbuf;
612 rx_strm.avail_out = AVAIL_OUT_SIZE(CHUNK_SIZE);
613 r = inflate(&rx_strm, Z_SYNC_FLUSH);
614 if (r != Z_OK && r != Z_BUF_ERROR) {
615 rprintf(FERROR, "inflate (token) returned %d\n", r);
616 exit_cleanup(RERR_STREAMIO);
617 }
618 } while (len || rx_strm.avail_out == 0);
619 }
620
621 /**
622 * Transmit a verbatim buffer of length @p n followed by a token.
623 * If token == -1 then we have reached EOF
624 * If n == 0 then don't send a buffer
625 */
626 void send_token(int f, int32 token, struct map_struct *buf, OFF_T offset,
627 int32 n, int32 toklen)
628 {
629 if (!do_compression)
630 simple_send_token(f, token, buf, offset, n);
631 else
632 send_deflated_token(f, token, buf, offset, n, toklen);
633 }
634
635 /*
636 * receive a token or buffer from the other end. If the reurn value is >0 then
637 * it is a data buffer of that length, and *data will point at the data.
638 * if the return value is -i then it represents token i-1
639 * if the return value is 0 then the end has been reached
640 */
641 int32 recv_token(int f, char **data)
642 {
643 int tok;
644
645 if (!do_compression) {
646 tok = simple_recv_token(f,data);
647 } else {
648 tok = recv_deflated_token(f, data);
649 }
650 return tok;
651 }
652
653 /*
654 * look at the data corresponding to a token, if necessary
655 */
656 void see_token(char *data, int32 toklen)
657 {
658 if (do_compression)
659 see_deflate_token(data, toklen);
660 }
rsync: a fast, versatile, remote (and local) file-copying tool