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) {
68 && (st->st_mode & CHMOD_BITS) != (file->mode & CHMOD_BITS))
71 if (am_root && preserve_uid && st->st_uid != file->uid)
74 if (preserve_gid && file->gid != GID_NONE
75 && st->st_gid != file->gid)
79 /* if always checksum is set then we use the checksum instead
80 of the file time to determine whether to sync */
81 if (always_checksum && S_ISREG(st->st_mode)) {
82 char sum[MD4_SUM_LENGTH];
83 char fnamecmpdest[MAXPATHLEN];
85 if (compare_dest != NULL) {
86 if (access(fname, 0) != 0) {
87 pathjoin(fnamecmpdest, sizeof fnamecmpdest,
92 file_checksum(fname,sum,st->st_size);
93 return memcmp(sum, file->u.sum, protocol_version < 21 ? 2
94 : MD4_SUM_LENGTH) == 0;
105 return (cmp_modtime(st->st_mtime,file->modtime) == 0);
110 * NULL sum_struct means we have no checksums
112 void write_sum_head(int f, struct sum_struct *sum)
114 static struct sum_struct null_sum;
119 write_int(f, sum->count);
120 write_int(f, sum->blength);
121 if (protocol_version >= 27)
122 write_int(f, sum->s2length);
123 write_int(f, sum->remainder);
127 * set (initialize) the size entries in the per-file sum_struct
128 * calculating dynamic block and checksum sizes.
130 * This is only called from generate_and_send_sums() but is a separate
131 * function to encapsulate the logic.
133 * The block size is a rounded square root of file length.
135 * The checksum size is determined according to:
136 * blocksum_bits = BLOCKSUM_EXP + 2*log2(file_len) - log2(block_len)
137 * provided by Donovan Baarda which gives a probability of rsync
138 * algorithm corrupting data and falling back using the whole md4
141 * This might be made one of several selectable heuristics.
144 static void sum_sizes_sqroot(struct sum_struct *sum, uint64 len)
146 unsigned int blength;
152 blength = block_size;
153 } else if (len <= BLOCK_SIZE * BLOCK_SIZE) {
154 blength = BLOCK_SIZE;
164 if (len < (uint64)blength * blength)
167 } while (c >= 8); /* round to multiple of 8 */
168 blength = MAX(blength, BLOCK_SIZE);
171 if (protocol_version < 27) {
172 s2length = csum_length;
173 } else if (csum_length == SUM_LENGTH) {
174 s2length = SUM_LENGTH;
176 int b = BLOCKSUM_BIAS;
182 while (c >>= 1 && b) {
185 s2length = (b + 1 - 32 + 7) / 8; /* add a bit,
188 * --optimize in compiler--
190 s2length = MAX(s2length, csum_length);
191 s2length = MIN(s2length, SUM_LENGTH);
195 sum->blength = blength;
196 sum->s2length = s2length;
197 sum->count = (len + (blength - 1)) / blength;
198 sum->remainder = (len % blength);
200 if (sum->count && verbose > 2) {
201 rprintf(FINFO, "count=%.0f rem=%u blength=%u s2length=%d flength=%.0f\n",
202 (double)sum->count, sum->remainder, sum->blength,
203 sum->s2length, (double)sum->flength);
208 * Perhaps we want to just send an empty checksum set for this file,
209 * which will force the whole thing to be literally transferred.
211 * When do we do this? If the user's explicitly said they
212 * want the whole thing, or if { they haven't explicitly
213 * requested a delta, and it's local but not batch mode.}
216 static BOOL disable_deltas_p(void)
220 if (whole_file == 0 || write_batch || read_batch)
227 * Generate and send a stream of signatures/checksums that describe a buffer
229 * Generate approximately one checksum every block_len bytes.
231 static void generate_and_send_sums(struct map_struct *buf, size_t len, int f_out)
234 struct sum_struct sum;
237 sum_sizes_sqroot(&sum, len);
239 write_sum_head(f_out, &sum);
241 for (i = 0; i < sum.count; i++) {
242 unsigned int n1 = MIN(len, sum.blength);
243 char *map = map_ptr(buf, offset, n1);
244 uint32 sum1 = get_checksum1(map, n1);
245 char sum2[SUM_LENGTH];
247 get_checksum2(map, n1, sum2);
251 "chunk[%.0f] offset=%.0f len=%u sum1=%08lx\n",
252 (double)i, (double)offset, n1,
253 (unsigned long)sum1);
255 write_int(f_out, sum1);
256 write_buf(f_out, sum2, sum.s2length);
265 * Acts on file number @p i from @p flist, whose name is @p fname.
267 * First fixes up permissions, then generates checksums for the file.
269 * @note This comment was added later by mbp who was trying to work it
270 * out. It might be wrong.
272 void recv_generator(char *fname, struct file_struct *file, int i, int f_out)
276 struct map_struct *mapbuf;
279 char fnamecmpbuf[MAXPATHLEN];
285 rprintf(FINFO,"recv_generator(%s,%d)\n",fname,i);
287 if (server_exclude_list.head
288 && check_exclude(&server_exclude_list, fname,
289 S_ISDIR(file->mode)) < 0) {
291 rprintf(FINFO, "skipping server-excluded file \"%s\"\n",
297 statret = link_stat(fname, &st, keep_dirlinks && S_ISDIR(file->mode));
299 if (only_existing && statret == -1 && errno == ENOENT) {
300 /* we only want to update existing files */
302 rprintf(FINFO, "not creating new file \"%s\"\n", fname);
308 (S_ISDIR(st.st_mode) == S_ISDIR(file->mode))) {
309 /* if the file exists already and we aren't perserving
310 * permissions then act as though the remote end sent
311 * us the file permissions we already have */
312 file->mode = (file->mode & ~CHMOD_BITS)
313 | (st.st_mode & CHMOD_BITS);
316 if (S_ISDIR(file->mode)) {
317 /* The file to be received is a directory, so we need
318 * to prepare appropriately. If there is already a
319 * file of that name and it is *not* a directory, then
320 * we need to delete it. If it doesn't exist, then
321 * recursively create it. */
324 return; /* TODO: causes inaccuracies -- fix */
325 if (statret == 0 && !S_ISDIR(st.st_mode)) {
326 if (robust_unlink(fname) != 0) {
327 rsyserr(FERROR, errno,
328 "recv_generator: unlink %s to make room for directory",
334 if (statret != 0 && do_mkdir(fname,file->mode) != 0 && errno != EEXIST) {
335 if (!(relative_paths && errno == ENOENT
336 && create_directory_path(fname, orig_umask) == 0
337 && do_mkdir(fname, file->mode) == 0)) {
338 rsyserr(FERROR, errno,
339 "recv_generator: mkdir %s failed",
343 /* f_out is set to -1 when doing final directory-permission
344 * and modification-time repair. */
345 if (set_perms(fname, file, statret ? NULL : &st, 0)
346 && verbose && f_out != -1)
347 rprintf(FINFO,"%s/\n",fname);
351 if (preserve_links && S_ISLNK(file->mode)) {
353 char lnk[MAXPATHLEN];
356 if (safe_symlinks && unsafe_symlink(file->u.link, fname)) {
358 rprintf(FINFO, "ignoring unsafe symlink %s -> \"%s\"\n",
359 full_fname(fname), file->u.link);
364 l = readlink(fname,lnk,MAXPATHLEN-1);
367 /* A link already pointing to the
368 * right place -- no further action
370 if (strcmp(lnk,file->u.link) == 0) {
371 set_perms(fname, file, &st,
376 /* Not a symlink, so delete whatever's
377 * already there and put a new symlink
381 if (do_symlink(file->u.link,fname) != 0) {
382 rsyserr(FERROR, errno, "symlink %s -> \"%s\" failed",
383 full_fname(fname), file->u.link);
385 set_perms(fname,file,NULL,0);
387 rprintf(FINFO,"%s -> %s\n", fname,file->u.link);
395 if (am_root && preserve_devices && IS_DEVICE(file->mode)) {
397 st.st_mode != file->mode ||
398 st.st_rdev != file->u.rdev) {
401 rprintf(FINFO,"mknod(%s,0%o,0x%x)\n",
402 fname,(int)file->mode,(int)file->u.rdev);
404 if (do_mknod(fname,file->mode,file->u.rdev) != 0) {
405 rsyserr(FERROR, errno, "mknod %s failed",
408 set_perms(fname,file,NULL,0);
410 rprintf(FINFO,"%s\n",fname);
413 set_perms(fname, file, &st, PERMS_REPORT);
419 if (preserve_hard_links && hard_link_check(file, HL_CHECK_MASTER))
422 if (!S_ISREG(file->mode)) {
423 rprintf(FINFO, "skipping non-regular file \"%s\"\n",fname);
429 if (statret == -1 && compare_dest != NULL) {
430 /* try the file at compare_dest instead */
431 int saveerrno = errno;
432 pathjoin(fnamecmpbuf, sizeof fnamecmpbuf, compare_dest, fname);
433 statret = link_stat(fnamecmpbuf, &st, 0);
434 if (!S_ISREG(st.st_mode))
439 else if (link_dest && !dry_run) {
440 if (do_link(fnamecmpbuf, fname) != 0) {
442 rsyserr(FINFO, errno, "link %s => %s",
446 fnamecmp = fnamecmpbuf;
450 fnamecmp = fnamecmpbuf;
454 if (preserve_hard_links && hard_link_check(file, HL_SKIP))
456 if (errno == ENOENT) {
459 write_sum_head(f_out, NULL);
460 } else if (verbose > 1) {
461 rsyserr(FERROR, errno,
462 "recv_generator: failed to open %s",
468 if (!S_ISREG(st.st_mode)) {
469 if (delete_file(fname) != 0) {
473 /* now pretend the file didn't exist */
474 if (preserve_hard_links && hard_link_check(file, HL_SKIP))
478 write_sum_head(f_out, NULL);
482 if (opt_ignore_existing && fnamecmp == fname) {
484 rprintf(FINFO,"%s exists\n",fname);
488 if (update_only && cmp_modtime(st.st_mtime,file->modtime)>0 && fnamecmp == fname) {
490 rprintf(FINFO,"%s is newer\n",fname);
494 if (skip_file(fname, file, &st)) {
495 if (fnamecmp == fname)
496 set_perms(fname, file, &st, PERMS_REPORT);
505 if (disable_deltas_p()) {
507 write_sum_head(f_out, NULL);
512 fd = do_open(fnamecmp, O_RDONLY, 0);
515 rsyserr(FERROR, errno, "failed to open %s, continuing",
516 full_fname(fnamecmp));
517 /* pretend the file didn't exist */
518 if (preserve_hard_links && hard_link_check(file, HL_SKIP))
521 write_sum_head(f_out, NULL);
526 mapbuf = map_file(fd,st.st_size);
531 rprintf(FINFO,"gen mapped %s of size %.0f\n", fnamecmp,
536 rprintf(FINFO, "generating and sending sums for %d\n", i);
539 generate_and_send_sums(mapbuf, st.st_size, f_out);
547 void generate_files(int f, struct file_list *flist, char *local_name)
551 char fbuf[MAXPATHLEN];
554 rprintf(FINFO, "generator starting pid=%ld count=%d\n",
555 (long)getpid(), flist->count);
561 ? "delta-transmission disabled for local transfer or --whole-file\n"
562 : "delta transmission enabled\n");
565 /* we expect to just sit around now, so don't exit on a
566 timeout. If we really get a timeout then the other process should
570 for (i = 0; i < flist->count; i++) {
571 struct file_struct *file = flist->files[i];
572 struct file_struct copy;
576 /* we need to ensure that any directories we create have writeable
577 permissions initially so that we can create the files within
578 them. This is then fixed after the files are transferred */
579 if (!am_root && S_ISDIR(file->mode) && !(file->mode & S_IWUSR)) {
581 /* XXX: Could this be causing a problem on SCO? Perhaps their
582 * handling of permissions is strange? */
583 copy.mode |= S_IWUSR; /* user write */
587 recv_generator(local_name ? local_name : f_name_to(file, fbuf),
592 csum_length = SUM_LENGTH;
596 rprintf(FINFO,"generate_files phase=%d\n",phase);
600 /* files can cycle through the system more than once
601 * to catch initial checksum errors */
602 while ((i = get_redo_num()) != -1) {
603 struct file_struct *file = flist->files[i];
604 recv_generator(local_name ? local_name : f_name_to(file, fbuf),
610 rprintf(FINFO,"generate_files phase=%d\n",phase);
614 if (preserve_hard_links)
617 /* now we need to fix any directory permissions that were
618 * modified during the transfer */
619 for (i = 0; i < flist->count; i++) {
620 struct file_struct *file = flist->files[i];
621 if (!file->basename || !S_ISDIR(file->mode))
623 recv_generator(local_name ? local_name : f_name(file),
628 rprintf(FINFO,"generate_files finished\n");