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;
40 extern int make_backups;
41 extern int csum_length;
42 extern int ignore_times;
44 extern int io_timeout;
45 extern int protocol_version;
46 extern int always_checksum;
47 extern char *partial_dir;
48 extern char *compare_dest;
50 extern int whole_file;
51 extern int local_server;
53 extern int read_batch;
54 extern int only_existing;
55 extern int orig_umask;
56 extern int safe_symlinks;
57 extern unsigned int block_size;
59 extern struct exclude_list_struct server_exclude_list;
62 /* choose whether to skip a particular file */
63 static int skip_file(char *fname, struct file_struct *file, STRUCT_STAT *st)
65 if (st->st_size != file->length)
69 && (st->st_mode & CHMOD_BITS) != (file->mode & CHMOD_BITS))
72 if (am_root && preserve_uid && st->st_uid != file->uid)
75 if (preserve_gid && file->gid != GID_NONE
76 && st->st_gid != file->gid)
80 /* if always checksum is set then we use the checksum instead
81 of the file time to determine whether to sync */
82 if (always_checksum && S_ISREG(st->st_mode)) {
83 char sum[MD4_SUM_LENGTH];
84 file_checksum(fname,sum,st->st_size);
85 return memcmp(sum, file->u.sum, protocol_version < 21 ? 2
86 : MD4_SUM_LENGTH) == 0;
95 return cmp_modtime(st->st_mtime, file->modtime) == 0;
100 * NULL sum_struct means we have no checksums
102 void write_sum_head(int f, struct sum_struct *sum)
104 static struct sum_struct null_sum;
109 write_int(f, sum->count);
110 write_int(f, sum->blength);
111 if (protocol_version >= 27)
112 write_int(f, sum->s2length);
113 write_int(f, sum->remainder);
117 * set (initialize) the size entries in the per-file sum_struct
118 * calculating dynamic block and checksum sizes.
120 * This is only called from generate_and_send_sums() but is a separate
121 * function to encapsulate the logic.
123 * The block size is a rounded square root of file length.
125 * The checksum size is determined according to:
126 * blocksum_bits = BLOCKSUM_EXP + 2*log2(file_len) - log2(block_len)
127 * provided by Donovan Baarda which gives a probability of rsync
128 * algorithm corrupting data and falling back using the whole md4
131 * This might be made one of several selectable heuristics.
134 static void sum_sizes_sqroot(struct sum_struct *sum, uint64 len)
136 unsigned int blength;
142 blength = block_size;
143 } else if (len <= BLOCK_SIZE * BLOCK_SIZE) {
144 blength = BLOCK_SIZE;
154 if (len < (uint64)blength * blength)
157 } while (c >= 8); /* round to multiple of 8 */
158 blength = MAX(blength, BLOCK_SIZE);
161 if (protocol_version < 27) {
162 s2length = csum_length;
163 } else if (csum_length == SUM_LENGTH) {
164 s2length = SUM_LENGTH;
166 int b = BLOCKSUM_BIAS;
172 while (c >>= 1 && b) {
175 s2length = (b + 1 - 32 + 7) / 8; /* add a bit,
178 * --optimize in compiler--
180 s2length = MAX(s2length, csum_length);
181 s2length = MIN(s2length, SUM_LENGTH);
185 sum->blength = blength;
186 sum->s2length = s2length;
187 sum->count = (len + (blength - 1)) / blength;
188 sum->remainder = (len % blength);
190 if (sum->count && verbose > 2) {
191 rprintf(FINFO, "count=%.0f rem=%u blength=%u s2length=%d flength=%.0f\n",
192 (double)sum->count, sum->remainder, sum->blength,
193 sum->s2length, (double)sum->flength);
199 * Generate and send a stream of signatures/checksums that describe a buffer
201 * Generate approximately one checksum every block_len bytes.
203 static void generate_and_send_sums(int fd, OFF_T len, int f_out, int f_copy)
206 struct map_struct *mapbuf;
207 struct sum_struct sum;
210 sum_sizes_sqroot(&sum, len);
213 mapbuf = map_file(fd, len, MAX_MAP_SIZE, sum.blength);
217 write_sum_head(f_out, &sum);
219 for (i = 0; i < sum.count; i++) {
220 unsigned int n1 = MIN(len, sum.blength);
221 char *map = map_ptr(mapbuf, offset, n1);
222 uint32 sum1 = get_checksum1(map, n1);
223 char sum2[SUM_LENGTH];
226 full_write(f_copy, map, n1);
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);
249 * Acts on file number @p i from @p flist, whose name is @p fname.
251 * First fixes up permissions, then generates checksums for the file.
253 * @note This comment was added later by mbp who was trying to work it
254 * out. It might be wrong.
256 static void recv_generator(char *fname, struct file_struct *file, int i,
260 STRUCT_STAT st, partial_st;
261 struct file_struct *back_file;
262 int statret, stat_errno;
263 char *fnamecmp, *partialptr, *backupptr;
264 char fnamecmpbuf[MAXPATHLEN];
270 rprintf(FINFO, "recv_generator(%s,%d)\n", safe_fname(fname), i);
272 if (server_exclude_list.head
273 && check_exclude(&server_exclude_list, fname,
274 S_ISDIR(file->mode)) < 0) {
276 rprintf(FINFO, "skipping server-excluded file \"%s\"\n",
286 statret = link_stat(fname, &st,
287 keep_dirlinks && S_ISDIR(file->mode));
291 if (only_existing && statret == -1 && stat_errno == ENOENT) {
292 /* we only want to update existing files */
294 rprintf(FINFO, "not creating new file \"%s\"\n",
300 if (statret == 0 && !preserve_perms
301 && S_ISDIR(st.st_mode) == S_ISDIR(file->mode)) {
302 /* if the file exists already and we aren't perserving
303 * permissions then act as though the remote end sent
304 * us the file permissions we already have */
305 file->mode = (file->mode & ~CHMOD_BITS)
306 | (st.st_mode & CHMOD_BITS);
309 if (S_ISDIR(file->mode)) {
310 /* The file to be received is a directory, so we need
311 * to prepare appropriately. If there is already a
312 * file of that name and it is *not* a directory, then
313 * we need to delete it. If it doesn't exist, then
314 * recursively create it. */
317 return; /* TODO: causes inaccuracies -- fix */
318 if (statret == 0 && !S_ISDIR(st.st_mode)) {
319 if (robust_unlink(fname) != 0) {
320 rsyserr(FERROR, errno,
321 "recv_generator: unlink %s to make room for directory",
327 if (statret != 0 && do_mkdir(fname,file->mode) != 0 && errno != EEXIST) {
328 if (!(relative_paths && errno == ENOENT
329 && create_directory_path(fname, orig_umask) == 0
330 && do_mkdir(fname, file->mode) == 0)) {
331 rsyserr(FERROR, errno,
332 "recv_generator: mkdir %s failed",
336 /* f_out is set to -1 when doing final directory-permission
337 * and modification-time repair. */
338 if (set_perms(fname, file, statret ? NULL : &st, 0)
339 && verbose && f_out != -1)
340 rprintf(FINFO, "%s/\n", safe_fname(fname));
344 if (preserve_links && S_ISLNK(file->mode)) {
346 char lnk[MAXPATHLEN];
349 if (safe_symlinks && unsafe_symlink(file->u.link, fname)) {
351 rprintf(FINFO, "ignoring unsafe symlink %s -> \"%s\"\n",
352 full_fname(fname), file->u.link);
357 l = readlink(fname,lnk,MAXPATHLEN-1);
360 /* A link already pointing to the
361 * right place -- no further action
363 if (strcmp(lnk,file->u.link) == 0) {
364 set_perms(fname, file, &st,
369 /* Not a symlink, so delete whatever's
370 * already there and put a new symlink
374 if (do_symlink(file->u.link,fname) != 0) {
375 rsyserr(FERROR, errno, "symlink %s -> \"%s\" failed",
376 full_fname(fname), safe_fname(file->u.link));
378 set_perms(fname,file,NULL,0);
380 rprintf(FINFO, "%s -> %s\n", safe_fname(fname),
381 safe_fname(file->u.link));
388 if (am_root && preserve_devices && IS_DEVICE(file->mode)) {
390 st.st_mode != file->mode ||
391 st.st_rdev != file->u.rdev) {
394 rprintf(FINFO,"mknod(%s,0%o,0x%x)\n",
396 (int)file->mode, (int)file->u.rdev);
398 if (do_mknod(fname,file->mode,file->u.rdev) != 0) {
399 rsyserr(FERROR, errno, "mknod %s failed",
402 set_perms(fname,file,NULL,0);
404 rprintf(FINFO, "%s\n",
409 set_perms(fname, file, &st, PERMS_REPORT);
414 if (preserve_hard_links && hard_link_check(file, HL_CHECK_MASTER))
417 if (!S_ISREG(file->mode)) {
418 rprintf(FINFO, "skipping non-regular file \"%s\"\n",
425 if (statret == -1 && compare_dest != NULL) {
426 /* try the file at compare_dest instead */
427 pathjoin(fnamecmpbuf, sizeof fnamecmpbuf, compare_dest, fname);
428 if (link_stat(fnamecmpbuf, &st, 0) == 0
429 && S_ISREG(st.st_mode)) {
431 if (link_dest && !dry_run) {
432 if (do_link(fnamecmpbuf, fname) < 0) {
434 rsyserr(FINFO, errno,
439 fnamecmp = fnamecmpbuf;
443 fnamecmp = fnamecmpbuf;
448 if (statret == 0 && !S_ISREG(st.st_mode)) {
449 if (delete_file(fname) != 0)
455 if (partial_dir && (partialptr = partial_dir_fname(fname))
456 && link_stat(partialptr, &partial_st, 0) == 0
457 && S_ISREG(partial_st.st_mode)) {
459 goto prepare_to_open;
464 if (preserve_hard_links && hard_link_check(file, HL_SKIP))
466 if (stat_errno == ENOENT) {
468 if (!dry_run && !read_batch)
469 write_sum_head(f_out, NULL);
470 } else if (verbose > 1) {
471 rsyserr(FERROR, stat_errno,
472 "recv_generator: failed to stat %s",
478 if (opt_ignore_existing && fnamecmp == fname) {
480 rprintf(FINFO, "%s exists\n", safe_fname(fname));
484 if (update_only && fnamecmp == fname
485 && cmp_modtime(st.st_mtime, file->modtime) > 0) {
487 rprintf(FINFO, "%s is newer\n", safe_fname(fname));
491 if (skip_file(fnamecmp, file, &st)) {
492 if (fnamecmp == fname)
493 set_perms(fname, file, &st, PERMS_REPORT);
498 if (dry_run || read_batch) {
503 if (whole_file > 0) {
505 write_sum_head(f_out, NULL);
511 fnamecmp = partialptr;
515 fd = do_open(fnamecmp, O_RDONLY, 0);
518 rsyserr(FERROR, errno, "failed to open %s, continuing",
519 full_fname(fnamecmp));
521 /* pretend the file didn't exist */
522 if (preserve_hard_links && hard_link_check(file, HL_SKIP))
525 write_sum_head(f_out, NULL);
529 if (inplace && make_backups) {
530 if (!(backupptr = get_backup_name(fname))) {
534 if (!(back_file = make_file(fname, NULL, NO_EXCLUDES))) {
536 goto pretend_missing;
538 if (robust_unlink(backupptr) && errno != ENOENT) {
539 rsyserr(FERROR, errno, "unlink %s",
540 full_fname(backupptr));
545 if ((f_copy = do_open(backupptr,
546 O_WRONLY | O_CREAT | O_TRUNC | O_EXCL, 0600)) < 0) {
547 rsyserr(FERROR, errno, "open %s",
548 full_fname(backupptr));
560 rprintf(FINFO, "gen mapped %s of size %.0f\n",
561 safe_fname(fnamecmp), (double)st.st_size);
565 rprintf(FINFO, "generating and sending sums for %d\n", i);
568 generate_and_send_sums(fd, st.st_size, f_out, f_copy);
572 set_perms(backupptr, back_file, NULL, 0);
574 rprintf(FINFO, "backed up %s to %s\n", fname, backupptr);
582 void generate_files(int f_out, struct file_list *flist, char *local_name)
586 char fbuf[MAXPATHLEN];
589 rprintf(FINFO, "generator starting pid=%ld count=%d\n",
590 (long)getpid(), flist->count);
596 ? "delta-transmission disabled for local transfer or --whole-file\n"
597 : "delta transmission enabled\n");
600 /* we expect to just sit around now, so don't exit on a
601 timeout. If we really get a timeout then the other process should
605 for (i = 0; i < flist->count; i++) {
606 struct file_struct *file = flist->files[i];
607 struct file_struct copy;
611 /* we need to ensure that any directories we create have writeable
612 permissions initially so that we can create the files within
613 them. This is then fixed after the files are transferred */
614 if (!am_root && S_ISDIR(file->mode) && !(file->mode & S_IWUSR)) {
616 /* XXX: Could this be causing a problem on SCO? Perhaps their
617 * handling of permissions is strange? */
618 copy.mode |= S_IWUSR; /* user write */
622 recv_generator(local_name ? local_name : f_name_to(file, fbuf),
627 csum_length = SUM_LENGTH;
631 rprintf(FINFO,"generate_files phase=%d\n",phase);
633 write_int(f_out, -1);
635 /* files can cycle through the system more than once
636 * to catch initial checksum errors */
637 while ((i = get_redo_num()) != -1) {
638 struct file_struct *file = flist->files[i];
639 recv_generator(local_name ? local_name : f_name_to(file, fbuf),
645 rprintf(FINFO,"generate_files phase=%d\n",phase);
647 write_int(f_out, -1);
649 if (preserve_hard_links)
652 /* now we need to fix any directory permissions that were
653 * modified during the transfer */
654 for (i = 0; i < flist->count; i++) {
655 struct file_struct *file = flist->files[i];
656 if (!file->basename || !S_ISDIR(file->mode))
658 recv_generator(local_name ? local_name : f_name(file),
663 rprintf(FINFO,"generate_files finished\n");