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,
257 int f_out, int f_out_name)
259 int fd = -1, f_copy = -1;
260 STRUCT_STAT st, partial_st;
261 struct file_struct *back_file = NULL;
262 int statret, stat_errno;
263 char *fnamecmp, *partialptr, *backupptr = NULL;
264 char fnamecmpbuf[MAXPATHLEN];
271 rprintf(FINFO, "recv_generator(%s,%d)\n", safe_fname(fname), i);
273 if (server_exclude_list.head
274 && check_exclude(&server_exclude_list, fname,
275 S_ISDIR(file->mode)) < 0) {
277 rprintf(FINFO, "skipping server-excluded file \"%s\"\n",
287 statret = link_stat(fname, &st,
288 keep_dirlinks && S_ISDIR(file->mode));
292 if (only_existing && statret == -1 && stat_errno == ENOENT) {
293 /* we only want to update existing files */
295 rprintf(FINFO, "not creating new file \"%s\"\n",
301 if (statret == 0 && !preserve_perms
302 && S_ISDIR(st.st_mode) == S_ISDIR(file->mode)) {
303 /* if the file exists already and we aren't perserving
304 * permissions then act as though the remote end sent
305 * us the file permissions we already have */
306 file->mode = (file->mode & ~CHMOD_BITS)
307 | (st.st_mode & CHMOD_BITS);
310 if (S_ISDIR(file->mode)) {
311 /* The file to be received is a directory, so we need
312 * to prepare appropriately. If there is already a
313 * file of that name and it is *not* a directory, then
314 * we need to delete it. If it doesn't exist, then
315 * recursively create it. */
318 return; /* TODO: causes inaccuracies -- fix */
319 if (statret == 0 && !S_ISDIR(st.st_mode)) {
320 if (robust_unlink(fname) != 0) {
321 rsyserr(FERROR, errno,
322 "recv_generator: unlink %s to make room for directory",
328 if (statret != 0 && do_mkdir(fname,file->mode) != 0 && errno != EEXIST) {
329 if (!(relative_paths && errno == ENOENT
330 && create_directory_path(fname, orig_umask) == 0
331 && do_mkdir(fname, file->mode) == 0)) {
332 rsyserr(FERROR, errno,
333 "recv_generator: mkdir %s failed",
337 /* f_out is set to -1 when doing final directory-permission
338 * and modification-time repair. */
339 if (set_perms(fname, file, statret ? NULL : &st, 0)
340 && verbose && f_out != -1)
341 rprintf(FINFO, "%s/\n", safe_fname(fname));
345 if (preserve_links && S_ISLNK(file->mode)) {
347 char lnk[MAXPATHLEN];
350 if (safe_symlinks && unsafe_symlink(file->u.link, fname)) {
352 rprintf(FINFO, "ignoring unsafe symlink %s -> \"%s\"\n",
353 full_fname(fname), file->u.link);
358 l = readlink(fname,lnk,MAXPATHLEN-1);
361 /* A link already pointing to the
362 * right place -- no further action
364 if (strcmp(lnk,file->u.link) == 0) {
365 set_perms(fname, file, &st,
370 /* Not a symlink, so delete whatever's
371 * already there and put a new symlink
375 if (do_symlink(file->u.link,fname) != 0) {
376 rsyserr(FERROR, errno, "symlink %s -> \"%s\" failed",
377 full_fname(fname), safe_fname(file->u.link));
379 set_perms(fname,file,NULL,0);
381 rprintf(FINFO, "%s -> %s\n", safe_fname(fname),
382 safe_fname(file->u.link));
389 if (am_root && preserve_devices && IS_DEVICE(file->mode)) {
391 st.st_mode != file->mode ||
392 st.st_rdev != file->u.rdev) {
395 rprintf(FINFO,"mknod(%s,0%o,0x%x)\n",
397 (int)file->mode, (int)file->u.rdev);
399 if (do_mknod(fname,file->mode,file->u.rdev) != 0) {
400 rsyserr(FERROR, errno, "mknod %s failed",
403 set_perms(fname,file,NULL,0);
405 rprintf(FINFO, "%s\n",
410 set_perms(fname, file, &st, PERMS_REPORT);
415 if (preserve_hard_links && hard_link_check(file, HL_CHECK_MASTER))
418 if (!S_ISREG(file->mode)) {
419 rprintf(FINFO, "skipping non-regular file \"%s\"\n",
425 fnamecmp_type = FNAMECMP_FNAME;
427 if (statret == -1 && compare_dest != NULL) {
428 /* try the file at compare_dest instead */
429 pathjoin(fnamecmpbuf, sizeof fnamecmpbuf, compare_dest, fname);
430 if (link_stat(fnamecmpbuf, &st, 0) == 0
431 && S_ISREG(st.st_mode)) {
433 if (link_dest && !dry_run) {
434 if (do_link(fnamecmpbuf, fname) < 0) {
436 rsyserr(FINFO, errno,
441 fnamecmp = fnamecmpbuf;
442 fnamecmp_type = FNAMECMP_CMPDEST;
447 fnamecmp = fnamecmpbuf;
448 fnamecmp_type = FNAMECMP_CMPDEST;
454 if (statret == 0 && !S_ISREG(st.st_mode)) {
455 if (delete_file(fname) != 0)
461 if (partial_dir && (partialptr = partial_dir_fname(fname))
462 && link_stat(partialptr, &partial_st, 0) == 0
463 && S_ISREG(partial_st.st_mode)) {
465 goto prepare_to_open;
470 if (preserve_hard_links && hard_link_check(file, HL_SKIP))
472 if (stat_errno == ENOENT)
475 rsyserr(FERROR, stat_errno,
476 "recv_generator: failed to stat %s",
482 if (opt_ignore_existing && fnamecmp_type == FNAMECMP_FNAME) {
484 rprintf(FINFO, "%s exists\n", safe_fname(fname));
488 if (update_only && fnamecmp_type == FNAMECMP_FNAME
489 && cmp_modtime(st.st_mtime, file->modtime) > 0) {
491 rprintf(FINFO, "%s is newer\n", safe_fname(fname));
495 if (skip_file(fnamecmp, file, &st)) {
496 if (fnamecmp_type == FNAMECMP_FNAME)
497 set_perms(fname, file, &st, PERMS_REPORT);
502 if (dry_run || whole_file > 0) {
511 fnamecmp = partialptr;
512 fnamecmp_type = FNAMECMP_PARTIAL_DIR;
516 fd = do_open(fnamecmp, O_RDONLY, 0);
519 rsyserr(FERROR, errno, "failed to open %s, continuing",
520 full_fname(fnamecmp));
522 /* pretend the file didn't exist */
523 if (preserve_hard_links && hard_link_check(file, HL_SKIP))
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));
553 fnamecmp_type = FNAMECMP_BACKUP;
557 rprintf(FINFO, "gen mapped %s of size %.0f\n",
558 safe_fname(fnamecmp), (double)st.st_size);
562 rprintf(FINFO, "generating and sending sums for %d\n", i);
567 write_byte(f_out_name, fnamecmp_type);
569 if (dry_run || read_batch)
573 generate_and_send_sums(fd, st.st_size, f_out, f_copy);
577 set_perms(backupptr, back_file, NULL, 0);
579 rprintf(FINFO, "backed up %s to %s\n",
587 write_sum_head(f_out, NULL);
591 void generate_files(int f_out, struct file_list *flist, char *local_name,
596 char fbuf[MAXPATHLEN];
599 rprintf(FINFO, "generator starting pid=%ld count=%d\n",
600 (long)getpid(), flist->count);
606 ? "delta-transmission disabled for local transfer or --whole-file\n"
607 : "delta transmission enabled\n");
610 /* we expect to just sit around now, so don't exit on a
611 timeout. If we really get a timeout then the other process should
615 for (i = 0; i < flist->count; i++) {
616 struct file_struct *file = flist->files[i];
617 struct file_struct copy;
621 /* we need to ensure that any directories we create have writeable
622 permissions initially so that we can create the files within
623 them. This is then fixed after the files are transferred */
624 if (!am_root && S_ISDIR(file->mode) && !(file->mode & S_IWUSR)) {
626 /* XXX: Could this be causing a problem on SCO? Perhaps their
627 * handling of permissions is strange? */
628 copy.mode |= S_IWUSR; /* user write */
632 recv_generator(local_name ? local_name : f_name_to(file, fbuf),
633 file, i, f_out, f_out_name);
637 csum_length = SUM_LENGTH;
641 rprintf(FINFO,"generate_files phase=%d\n",phase);
643 write_int(f_out, -1);
645 /* files can cycle through the system more than once
646 * to catch initial checksum errors */
647 while ((i = get_redo_num()) != -1) {
648 struct file_struct *file = flist->files[i];
649 recv_generator(local_name ? local_name : f_name_to(file, fbuf),
650 file, i, f_out, f_out_name);
655 rprintf(FINFO,"generate_files phase=%d\n",phase);
657 write_int(f_out, -1);
659 if (preserve_hard_links)
662 /* now we need to fix any directory permissions that were
663 * modified during the transfer */
664 for (i = 0; i < flist->count; i++) {
665 struct file_struct *file = flist->files[i];
666 if (!file->basename || !S_ISDIR(file->mode))
668 recv_generator(local_name ? local_name : f_name(file),
673 rprintf(FINFO,"generate_files finished\n");