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;
50 extern int read_batch;
51 extern int only_existing;
52 extern int orig_umask;
53 extern int safe_symlinks;
54 extern unsigned int block_size;
55 extern unsigned int max_map_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);
166 blength = MIN(blength, MAX_MAP_SIZE);
168 max_map_size = MAX(MAX_MAP_SIZE, blength * 32);
170 if (protocol_version < 27) {
171 s2length = csum_length;
172 } else if (csum_length == SUM_LENGTH) {
173 s2length = SUM_LENGTH;
175 int b = BLOCKSUM_BIAS;
181 while (c >>= 1 && b) {
184 s2length = (b + 1 - 32 + 7) / 8; /* add a bit,
187 * --optimize in compiler--
189 s2length = MAX(s2length, csum_length);
190 s2length = MIN(s2length, SUM_LENGTH);
194 sum->blength = blength;
195 sum->s2length = s2length;
196 sum->count = (len + (blength - 1)) / blength;
197 sum->remainder = (len % blength);
199 if (sum->count && verbose > 2) {
200 rprintf(FINFO, "count=%.0f rem=%u blength=%u s2length=%d flength=%.0f\n",
201 (double)sum->count, sum->remainder, sum->blength,
202 sum->s2length, (double)sum->flength);
208 * Generate and send a stream of signatures/checksums that describe a buffer
210 * Generate approximately one checksum every block_len bytes.
212 static void generate_and_send_sums(struct map_struct *buf, OFF_T len, int f_out)
215 struct sum_struct sum;
218 sum_sizes_sqroot(&sum, len);
220 write_sum_head(f_out, &sum);
222 for (i = 0; i < sum.count; i++) {
223 unsigned int n1 = MIN(len, sum.blength);
224 char *map = map_ptr(buf, offset, n1);
225 uint32 sum1 = get_checksum1(map, n1);
226 char sum2[SUM_LENGTH];
228 get_checksum2(map, n1, sum2);
232 "chunk[%.0f] offset=%.0f len=%u sum1=%08lx\n",
233 (double)i, (double)offset, n1,
234 (unsigned long)sum1);
236 write_int(f_out, sum1);
237 write_buf(f_out, sum2, sum.s2length);
246 * Acts on file number @p i from @p flist, whose name is @p fname.
248 * First fixes up permissions, then generates checksums for the file.
250 * @note This comment was added later by mbp who was trying to work it
251 * out. It might be wrong.
253 static void recv_generator(char *fname, struct file_struct *file, int i,
258 struct map_struct *mapbuf;
261 char fnamecmpbuf[MAXPATHLEN];
267 rprintf(FINFO,"recv_generator(%s,%d)\n",fname,i);
269 if (server_exclude_list.head
270 && check_exclude(&server_exclude_list, fname,
271 S_ISDIR(file->mode)) < 0) {
273 rprintf(FINFO, "skipping server-excluded file \"%s\"\n",
279 statret = link_stat(fname, &st, keep_dirlinks && S_ISDIR(file->mode));
281 if (only_existing && statret == -1 && errno == ENOENT) {
282 /* we only want to update existing files */
284 rprintf(FINFO, "not creating new file \"%s\"\n", fname);
290 (S_ISDIR(st.st_mode) == S_ISDIR(file->mode))) {
291 /* if the file exists already and we aren't perserving
292 * permissions then act as though the remote end sent
293 * us the file permissions we already have */
294 file->mode = (file->mode & ~CHMOD_BITS)
295 | (st.st_mode & CHMOD_BITS);
298 if (S_ISDIR(file->mode)) {
299 /* The file to be received is a directory, so we need
300 * to prepare appropriately. If there is already a
301 * file of that name and it is *not* a directory, then
302 * we need to delete it. If it doesn't exist, then
303 * recursively create it. */
306 return; /* TODO: causes inaccuracies -- fix */
307 if (statret == 0 && !S_ISDIR(st.st_mode)) {
308 if (robust_unlink(fname) != 0) {
309 rsyserr(FERROR, errno,
310 "recv_generator: unlink %s to make room for directory",
316 if (statret != 0 && do_mkdir(fname,file->mode) != 0 && errno != EEXIST) {
317 if (!(relative_paths && errno == ENOENT
318 && create_directory_path(fname, orig_umask) == 0
319 && do_mkdir(fname, file->mode) == 0)) {
320 rsyserr(FERROR, errno,
321 "recv_generator: mkdir %s failed",
325 /* f_out is set to -1 when doing final directory-permission
326 * and modification-time repair. */
327 if (set_perms(fname, file, statret ? NULL : &st, 0)
328 && verbose && f_out != -1)
329 rprintf(FINFO,"%s/\n",fname);
333 if (preserve_links && S_ISLNK(file->mode)) {
335 char lnk[MAXPATHLEN];
338 if (safe_symlinks && unsafe_symlink(file->u.link, fname)) {
340 rprintf(FINFO, "ignoring unsafe symlink %s -> \"%s\"\n",
341 full_fname(fname), file->u.link);
346 l = readlink(fname,lnk,MAXPATHLEN-1);
349 /* A link already pointing to the
350 * right place -- no further action
352 if (strcmp(lnk,file->u.link) == 0) {
353 set_perms(fname, file, &st,
358 /* Not a symlink, so delete whatever's
359 * already there and put a new symlink
363 if (do_symlink(file->u.link,fname) != 0) {
364 rsyserr(FERROR, errno, "symlink %s -> \"%s\" failed",
365 full_fname(fname), file->u.link);
367 set_perms(fname,file,NULL,0);
369 rprintf(FINFO,"%s -> %s\n", fname,file->u.link);
377 if (am_root && preserve_devices && IS_DEVICE(file->mode)) {
379 st.st_mode != file->mode ||
380 st.st_rdev != file->u.rdev) {
383 rprintf(FINFO,"mknod(%s,0%o,0x%x)\n",
384 fname,(int)file->mode,(int)file->u.rdev);
386 if (do_mknod(fname,file->mode,file->u.rdev) != 0) {
387 rsyserr(FERROR, errno, "mknod %s failed",
390 set_perms(fname,file,NULL,0);
392 rprintf(FINFO,"%s\n",fname);
395 set_perms(fname, file, &st, PERMS_REPORT);
404 if (preserve_hard_links && hard_link_check(file, HL_CHECK_MASTER))
407 if (!S_ISREG(file->mode)) {
408 rprintf(FINFO, "skipping non-regular file \"%s\"\n",fname);
414 if (statret == -1 && compare_dest != NULL) {
415 /* try the file at compare_dest instead */
416 int saveerrno = errno;
417 pathjoin(fnamecmpbuf, sizeof fnamecmpbuf, compare_dest, fname);
418 statret = link_stat(fnamecmpbuf, &st, 0);
419 if (!S_ISREG(st.st_mode))
424 else if (link_dest && !dry_run) {
425 if (do_link(fnamecmpbuf, fname) != 0) {
427 rsyserr(FINFO, errno, "link %s => %s",
431 fnamecmp = fnamecmpbuf;
435 fnamecmp = fnamecmpbuf;
439 if (preserve_hard_links && hard_link_check(file, HL_SKIP))
441 if (errno == ENOENT) {
444 write_sum_head(f_out, NULL);
445 } else if (verbose > 1) {
446 rsyserr(FERROR, errno,
447 "recv_generator: failed to open %s",
453 if (!S_ISREG(st.st_mode)) {
454 if (delete_file(fname) != 0) {
458 /* now pretend the file didn't exist */
459 if (preserve_hard_links && hard_link_check(file, HL_SKIP))
463 write_sum_head(f_out, NULL);
467 if (opt_ignore_existing && fnamecmp == fname) {
469 rprintf(FINFO,"%s exists\n",fname);
473 if (update_only && fnamecmp == fname
474 && cmp_modtime(st.st_mtime, file->modtime) > 0) {
476 rprintf(FINFO,"%s is newer\n",fname);
480 if (skip_file(fname, file, &st)) {
481 if (fnamecmp == fname)
482 set_perms(fname, file, &st, PERMS_REPORT);
491 if (whole_file > 0) {
493 write_sum_head(f_out, NULL);
498 fd = do_open(fnamecmp, O_RDONLY, 0);
501 rsyserr(FERROR, errno, "failed to open %s, continuing",
502 full_fname(fnamecmp));
503 /* pretend the file didn't exist */
504 if (preserve_hard_links && hard_link_check(file, HL_SKIP))
507 write_sum_head(f_out, NULL);
512 mapbuf = map_file(fd,st.st_size);
517 rprintf(FINFO,"gen mapped %s of size %.0f\n", fnamecmp,
522 rprintf(FINFO, "generating and sending sums for %d\n", i);
525 generate_and_send_sums(mapbuf, st.st_size, f_out);
533 void generate_files(int f_out, struct file_list *flist, char *local_name)
537 char fbuf[MAXPATHLEN];
540 rprintf(FINFO, "generator starting pid=%ld count=%d\n",
541 (long)getpid(), flist->count);
547 ? "delta-transmission disabled for local transfer or --whole-file\n"
548 : "delta transmission enabled\n");
551 /* we expect to just sit around now, so don't exit on a
552 timeout. If we really get a timeout then the other process should
556 for (i = 0; i < flist->count; i++) {
557 struct file_struct *file = flist->files[i];
558 struct file_struct copy;
562 /* we need to ensure that any directories we create have writeable
563 permissions initially so that we can create the files within
564 them. This is then fixed after the files are transferred */
565 if (!am_root && S_ISDIR(file->mode) && !(file->mode & S_IWUSR)) {
567 /* XXX: Could this be causing a problem on SCO? Perhaps their
568 * handling of permissions is strange? */
569 copy.mode |= S_IWUSR; /* user write */
573 recv_generator(local_name ? local_name : f_name_to(file, fbuf),
578 csum_length = SUM_LENGTH;
582 rprintf(FINFO,"generate_files phase=%d\n",phase);
584 write_int(f_out, -1);
586 /* files can cycle through the system more than once
587 * to catch initial checksum errors */
588 while ((i = get_redo_num()) != -1) {
589 struct file_struct *file = flist->files[i];
590 recv_generator(local_name ? local_name : f_name_to(file, fbuf),
596 rprintf(FINFO,"generate_files phase=%d\n",phase);
598 write_int(f_out, -1);
600 if (preserve_hard_links)
603 /* now we need to fix any directory permissions that were
604 * modified during the transfer */
605 for (i = 0; i < flist->count; i++) {
606 struct file_struct *file = flist->files[i];
607 if (!file->basename || !S_ISDIR(file->mode))
609 recv_generator(local_name ? local_name : f_name(file),
614 rprintf(FINFO,"generate_files finished\n");