1 /* -*- c-file-style: "linux" -*-
3 rsync -- fast file replication program
5 Copyright (C) 1996-2000 by Andrew Tridgell
6 Copyright (C) Paul Mackerras 1996
7 Copyright (C) 2002 by Martin Pool <mbp@samba.org>
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 2 of the License, or
12 (at your option) any later version.
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with this program; if not, write to the Free Software
21 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
28 extern int relative_paths;
29 extern int keep_dirlinks;
30 extern int preserve_links;
32 extern int preserve_devices;
33 extern int preserve_hard_links;
34 extern int preserve_perms;
35 extern int preserve_uid;
36 extern int preserve_gid;
37 extern int update_only;
38 extern int opt_ignore_existing;
39 extern int csum_length;
40 extern int ignore_times;
42 extern int io_timeout;
43 extern int protocol_version;
44 extern int always_checksum;
45 extern char *compare_dest;
47 extern int whole_file;
48 extern int local_server;
49 extern int read_batch;
50 extern int write_batch;
52 extern int only_existing;
53 extern int orig_umask;
54 extern int safe_symlinks;
55 extern unsigned int block_size;
57 extern struct exclude_list_struct server_exclude_list;
60 /* choose whether to skip a particular file */
61 static int skip_file(char *fname, struct file_struct *file, STRUCT_STAT *st)
63 if (st->st_size != file->length)
67 && (st->st_mode & CHMOD_BITS) != (file->mode & CHMOD_BITS))
70 if (am_root && preserve_uid && st->st_uid != file->uid)
73 if (preserve_gid && file->gid != GID_NONE
74 && st->st_gid != file->gid)
78 /* if always checksum is set then we use the checksum instead
79 of the file time to determine whether to sync */
80 if (always_checksum && S_ISREG(st->st_mode)) {
81 char sum[MD4_SUM_LENGTH];
82 char fnamecmpdest[MAXPATHLEN];
84 if (compare_dest != NULL) {
85 if (access(fname, 0) != 0) {
86 pathjoin(fnamecmpdest, sizeof fnamecmpdest,
91 file_checksum(fname,sum,st->st_size);
92 return memcmp(sum, file->u.sum, protocol_version < 21 ? 2
93 : MD4_SUM_LENGTH) == 0;
102 return cmp_modtime(st->st_mtime, file->modtime) == 0;
107 * NULL sum_struct means we have no checksums
109 void write_sum_head(int f, struct sum_struct *sum)
111 static struct sum_struct null_sum;
116 write_int(f, sum->count);
117 write_int(f, sum->blength);
118 if (protocol_version >= 27)
119 write_int(f, sum->s2length);
120 write_int(f, sum->remainder);
124 * set (initialize) the size entries in the per-file sum_struct
125 * calculating dynamic block and checksum sizes.
127 * This is only called from generate_and_send_sums() but is a separate
128 * function to encapsulate the logic.
130 * The block size is a rounded square root of file length.
132 * The checksum size is determined according to:
133 * blocksum_bits = BLOCKSUM_EXP + 2*log2(file_len) - log2(block_len)
134 * provided by Donovan Baarda which gives a probability of rsync
135 * algorithm corrupting data and falling back using the whole md4
138 * This might be made one of several selectable heuristics.
141 static void sum_sizes_sqroot(struct sum_struct *sum, uint64 len)
143 unsigned int blength;
149 blength = block_size;
150 } else if (len <= BLOCK_SIZE * BLOCK_SIZE) {
151 blength = BLOCK_SIZE;
161 if (len < (uint64)blength * blength)
164 } while (c >= 8); /* round to multiple of 8 */
165 blength = MAX(blength, BLOCK_SIZE);
168 if (protocol_version < 27) {
169 s2length = csum_length;
170 } else if (csum_length == SUM_LENGTH) {
171 s2length = SUM_LENGTH;
173 int b = BLOCKSUM_BIAS;
179 while (c >>= 1 && b) {
182 s2length = (b + 1 - 32 + 7) / 8; /* add a bit,
185 * --optimize in compiler--
187 s2length = MAX(s2length, csum_length);
188 s2length = MIN(s2length, SUM_LENGTH);
192 sum->blength = blength;
193 sum->s2length = s2length;
194 sum->count = (len + (blength - 1)) / blength;
195 sum->remainder = (len % blength);
197 if (sum->count && verbose > 2) {
198 rprintf(FINFO, "count=%.0f rem=%u blength=%u s2length=%d flength=%.0f\n",
199 (double)sum->count, sum->remainder, sum->blength,
200 sum->s2length, (double)sum->flength);
205 * Perhaps we want to just send an empty checksum set for this file,
206 * which will force the whole thing to be literally transferred.
208 * When do we do this? If the user's explicitly said they
209 * want the whole thing, or if { they haven't explicitly
210 * requested a delta, and it's local but not batch mode.}
213 static BOOL disable_deltas_p(void)
217 if (whole_file == 0 || write_batch || read_batch)
224 * Generate and send a stream of signatures/checksums that describe a buffer
226 * Generate approximately one checksum every block_len bytes.
228 static void generate_and_send_sums(struct map_struct *buf, size_t len, int f_out)
231 struct sum_struct sum;
234 sum_sizes_sqroot(&sum, len);
236 write_sum_head(f_out, &sum);
238 for (i = 0; i < sum.count; i++) {
239 unsigned int n1 = MIN(len, sum.blength);
240 char *map = map_ptr(buf, offset, n1);
241 uint32 sum1 = get_checksum1(map, n1);
242 char sum2[SUM_LENGTH];
244 get_checksum2(map, n1, sum2);
248 "chunk[%.0f] offset=%.0f len=%u sum1=%08lx\n",
249 (double)i, (double)offset, n1,
250 (unsigned long)sum1);
252 write_int(f_out, sum1);
253 write_buf(f_out, sum2, sum.s2length);
262 * Acts on file number @p i from @p flist, whose name is @p fname.
264 * First fixes up permissions, then generates checksums for the file.
266 * @note This comment was added later by mbp who was trying to work it
267 * out. It might be wrong.
269 static void recv_generator(char *fname, struct file_struct *file, int i,
274 struct map_struct *mapbuf;
277 char fnamecmpbuf[MAXPATHLEN];
283 rprintf(FINFO,"recv_generator(%s,%d)\n",fname,i);
285 if (server_exclude_list.head
286 && check_exclude(&server_exclude_list, fname,
287 S_ISDIR(file->mode)) < 0) {
289 rprintf(FINFO, "skipping server-excluded file \"%s\"\n",
295 statret = link_stat(fname, &st, keep_dirlinks && S_ISDIR(file->mode));
297 if (only_existing && statret == -1 && errno == ENOENT) {
298 /* we only want to update existing files */
300 rprintf(FINFO, "not creating new file \"%s\"\n", fname);
306 (S_ISDIR(st.st_mode) == S_ISDIR(file->mode))) {
307 /* if the file exists already and we aren't perserving
308 * permissions then act as though the remote end sent
309 * us the file permissions we already have */
310 file->mode = (file->mode & ~CHMOD_BITS)
311 | (st.st_mode & CHMOD_BITS);
314 if (S_ISDIR(file->mode)) {
315 /* The file to be received is a directory, so we need
316 * to prepare appropriately. If there is already a
317 * file of that name and it is *not* a directory, then
318 * we need to delete it. If it doesn't exist, then
319 * recursively create it. */
322 return; /* TODO: causes inaccuracies -- fix */
323 if (statret == 0 && !S_ISDIR(st.st_mode)) {
324 if (robust_unlink(fname) != 0) {
325 rsyserr(FERROR, errno,
326 "recv_generator: unlink %s to make room for directory",
332 if (statret != 0 && do_mkdir(fname,file->mode) != 0 && errno != EEXIST) {
333 if (!(relative_paths && errno == ENOENT
334 && create_directory_path(fname, orig_umask) == 0
335 && do_mkdir(fname, file->mode) == 0)) {
336 rsyserr(FERROR, errno,
337 "recv_generator: mkdir %s failed",
341 /* f_out is set to -1 when doing final directory-permission
342 * and modification-time repair. */
343 if (set_perms(fname, file, statret ? NULL : &st, 0)
344 && verbose && f_out != -1)
345 rprintf(FINFO,"%s/\n",fname);
349 if (preserve_links && S_ISLNK(file->mode)) {
351 char lnk[MAXPATHLEN];
354 if (safe_symlinks && unsafe_symlink(file->u.link, fname)) {
356 rprintf(FINFO, "ignoring unsafe symlink %s -> \"%s\"\n",
357 full_fname(fname), file->u.link);
362 l = readlink(fname,lnk,MAXPATHLEN-1);
365 /* A link already pointing to the
366 * right place -- no further action
368 if (strcmp(lnk,file->u.link) == 0) {
369 set_perms(fname, file, &st,
374 /* Not a symlink, so delete whatever's
375 * already there and put a new symlink
379 if (do_symlink(file->u.link,fname) != 0) {
380 rsyserr(FERROR, errno, "symlink %s -> \"%s\" failed",
381 full_fname(fname), file->u.link);
383 set_perms(fname,file,NULL,0);
385 rprintf(FINFO,"%s -> %s\n", fname,file->u.link);
393 if (am_root && preserve_devices && IS_DEVICE(file->mode)) {
395 st.st_mode != file->mode ||
396 st.st_rdev != file->u.rdev) {
399 rprintf(FINFO,"mknod(%s,0%o,0x%x)\n",
400 fname,(int)file->mode,(int)file->u.rdev);
402 if (do_mknod(fname,file->mode,file->u.rdev) != 0) {
403 rsyserr(FERROR, errno, "mknod %s failed",
406 set_perms(fname,file,NULL,0);
408 rprintf(FINFO,"%s\n",fname);
411 set_perms(fname, file, &st, PERMS_REPORT);
417 if (preserve_hard_links && hard_link_check(file, HL_CHECK_MASTER))
420 if (!S_ISREG(file->mode)) {
421 rprintf(FINFO, "skipping non-regular file \"%s\"\n",fname);
427 if (statret == -1 && compare_dest != NULL) {
428 /* try the file at compare_dest instead */
429 int saveerrno = errno;
430 pathjoin(fnamecmpbuf, sizeof fnamecmpbuf, compare_dest, fname);
431 statret = link_stat(fnamecmpbuf, &st, 0);
432 if (!S_ISREG(st.st_mode))
437 else if (link_dest && !dry_run) {
438 if (do_link(fnamecmpbuf, fname) != 0) {
440 rsyserr(FINFO, errno, "link %s => %s",
444 fnamecmp = fnamecmpbuf;
448 fnamecmp = fnamecmpbuf;
452 if (preserve_hard_links && hard_link_check(file, HL_SKIP))
454 if (errno == ENOENT) {
457 write_sum_head(f_out, NULL);
458 } else if (verbose > 1) {
459 rsyserr(FERROR, errno,
460 "recv_generator: failed to open %s",
466 if (!S_ISREG(st.st_mode)) {
467 if (delete_file(fname) != 0) {
471 /* now pretend the file didn't exist */
472 if (preserve_hard_links && hard_link_check(file, HL_SKIP))
476 write_sum_head(f_out, NULL);
480 if (opt_ignore_existing && fnamecmp == fname) {
482 rprintf(FINFO,"%s exists\n",fname);
486 if (update_only && fnamecmp == fname
487 && cmp_modtime(st.st_mtime, file->modtime) > 0) {
489 rprintf(FINFO,"%s is newer\n",fname);
493 if (skip_file(fname, file, &st)) {
494 if (fnamecmp == fname)
495 set_perms(fname, file, &st, PERMS_REPORT);
504 if (disable_deltas_p()) {
506 write_sum_head(f_out, NULL);
511 fd = do_open(fnamecmp, O_RDONLY, 0);
514 rsyserr(FERROR, errno, "failed to open %s, continuing",
515 full_fname(fnamecmp));
516 /* pretend the file didn't exist */
517 if (preserve_hard_links && hard_link_check(file, HL_SKIP))
520 write_sum_head(f_out, NULL);
525 mapbuf = map_file(fd,st.st_size);
530 rprintf(FINFO,"gen mapped %s of size %.0f\n", fnamecmp,
535 rprintf(FINFO, "generating and sending sums for %d\n", i);
538 generate_and_send_sums(mapbuf, st.st_size, f_out);
546 void generate_files(int f, struct file_list *flist, char *local_name)
550 char fbuf[MAXPATHLEN];
553 rprintf(FINFO, "generator starting pid=%ld count=%d\n",
554 (long)getpid(), flist->count);
560 ? "delta-transmission disabled for local transfer or --whole-file\n"
561 : "delta transmission enabled\n");
564 /* we expect to just sit around now, so don't exit on a
565 timeout. If we really get a timeout then the other process should
569 for (i = 0; i < flist->count; i++) {
570 struct file_struct *file = flist->files[i];
571 struct file_struct copy;
575 /* we need to ensure that any directories we create have writeable
576 permissions initially so that we can create the files within
577 them. This is then fixed after the files are transferred */
578 if (!am_root && S_ISDIR(file->mode) && !(file->mode & S_IWUSR)) {
580 /* XXX: Could this be causing a problem on SCO? Perhaps their
581 * handling of permissions is strange? */
582 copy.mode |= S_IWUSR; /* user write */
586 recv_generator(local_name ? local_name : f_name_to(file, fbuf),
591 csum_length = SUM_LENGTH;
595 rprintf(FINFO,"generate_files phase=%d\n",phase);
599 /* files can cycle through the system more than once
600 * to catch initial checksum errors */
601 while ((i = get_redo_num()) != -1) {
602 struct file_struct *file = flist->files[i];
603 recv_generator(local_name ? local_name : f_name_to(file, fbuf),
609 rprintf(FINFO,"generate_files phase=%d\n",phase);
613 if (preserve_hard_links)
616 /* now we need to fix any directory permissions that were
617 * modified during the transfer */
618 for (i = 0; i < flist->count; i++) {
619 struct file_struct *file = flist->files[i];
620 if (!file->basename || !S_ISDIR(file->mode))
622 recv_generator(local_name ? local_name : f_name(file),
627 rprintf(FINFO,"generate_files finished\n");