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;
56 extern struct exclude_list_struct server_exclude_list;
59 /* choose whether to skip a particular file */
60 static int skip_file(char *fname, struct file_struct *file, STRUCT_STAT *st)
62 if (st->st_size != file->length)
66 && (st->st_mode & CHMOD_BITS) != (file->mode & CHMOD_BITS))
69 if (am_root && preserve_uid && st->st_uid != file->uid)
72 if (preserve_gid && file->gid != GID_NONE
73 && st->st_gid != file->gid)
77 /* if always checksum is set then we use the checksum instead
78 of the file time to determine whether to sync */
79 if (always_checksum && S_ISREG(st->st_mode)) {
80 char sum[MD4_SUM_LENGTH];
81 char fnamecmpdest[MAXPATHLEN];
83 if (compare_dest != NULL) {
84 if (access(fname, 0) != 0) {
85 pathjoin(fnamecmpdest, sizeof fnamecmpdest,
90 file_checksum(fname,sum,st->st_size);
91 return memcmp(sum, file->u.sum, protocol_version < 21 ? 2
92 : MD4_SUM_LENGTH) == 0;
101 return cmp_modtime(st->st_mtime, file->modtime) == 0;
106 * NULL sum_struct means we have no checksums
108 void write_sum_head(int f, struct sum_struct *sum)
110 static struct sum_struct null_sum;
115 write_int(f, sum->count);
116 write_int(f, sum->blength);
117 if (protocol_version >= 27)
118 write_int(f, sum->s2length);
119 write_int(f, sum->remainder);
123 * set (initialize) the size entries in the per-file sum_struct
124 * calculating dynamic block and checksum sizes.
126 * This is only called from generate_and_send_sums() but is a separate
127 * function to encapsulate the logic.
129 * The block size is a rounded square root of file length.
131 * The checksum size is determined according to:
132 * blocksum_bits = BLOCKSUM_EXP + 2*log2(file_len) - log2(block_len)
133 * provided by Donovan Baarda which gives a probability of rsync
134 * algorithm corrupting data and falling back using the whole md4
137 * This might be made one of several selectable heuristics.
140 static void sum_sizes_sqroot(struct sum_struct *sum, uint64 len)
142 unsigned int blength;
148 blength = block_size;
149 } else if (len <= BLOCK_SIZE * BLOCK_SIZE) {
150 blength = BLOCK_SIZE;
160 if (len < (uint64)blength * blength)
163 } while (c >= 8); /* round to multiple of 8 */
164 blength = MAX(blength, BLOCK_SIZE);
165 blength = MIN(blength, MAX_MAP_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);
206 * Generate and send a stream of signatures/checksums that describe a buffer
208 * Generate approximately one checksum every block_len bytes.
210 static void generate_and_send_sums(int fd, OFF_T len, int f_out)
213 struct map_struct *mapbuf;
214 struct sum_struct sum;
217 sum_sizes_sqroot(&sum, len);
220 mapbuf = map_file(fd, len, sum.blength);
224 write_sum_head(f_out, &sum);
226 for (i = 0; i < sum.count; i++) {
227 unsigned int n1 = MIN(len, sum.blength);
228 char *map = map_ptr(mapbuf, offset, n1);
229 uint32 sum1 = get_checksum1(map, n1);
230 char sum2[SUM_LENGTH];
232 get_checksum2(map, n1, sum2);
236 "chunk[%.0f] offset=%.0f len=%u sum1=%08lx\n",
237 (double)i, (double)offset, n1,
238 (unsigned long)sum1);
240 write_int(f_out, sum1);
241 write_buf(f_out, sum2, sum.s2length);
253 * Acts on file number @p i from @p flist, whose name is @p fname.
255 * First fixes up permissions, then generates checksums for the file.
257 * @note This comment was added later by mbp who was trying to work it
258 * out. It might be wrong.
260 static void recv_generator(char *fname, struct file_struct *file, int i,
267 char fnamecmpbuf[MAXPATHLEN];
273 rprintf(FINFO,"recv_generator(%s,%d)\n",fname,i);
275 if (server_exclude_list.head
276 && check_exclude(&server_exclude_list, fname,
277 S_ISDIR(file->mode)) < 0) {
279 rprintf(FINFO, "skipping server-excluded file \"%s\"\n",
285 statret = link_stat(fname, &st, keep_dirlinks && S_ISDIR(file->mode));
287 if (only_existing && statret == -1 && errno == ENOENT) {
288 /* we only want to update existing files */
290 rprintf(FINFO, "not creating new file \"%s\"\n", fname);
294 if (statret == 0 && !preserve_perms
295 && S_ISDIR(st.st_mode) == S_ISDIR(file->mode)) {
296 /* if the file exists already and we aren't perserving
297 * permissions then act as though the remote end sent
298 * us the file permissions we already have */
299 file->mode = (file->mode & ~CHMOD_BITS)
300 | (st.st_mode & CHMOD_BITS);
303 if (S_ISDIR(file->mode)) {
304 /* The file to be received is a directory, so we need
305 * to prepare appropriately. If there is already a
306 * file of that name and it is *not* a directory, then
307 * we need to delete it. If it doesn't exist, then
308 * recursively create it. */
311 return; /* TODO: causes inaccuracies -- fix */
312 if (statret == 0 && !S_ISDIR(st.st_mode)) {
313 if (robust_unlink(fname) != 0) {
314 rsyserr(FERROR, errno,
315 "recv_generator: unlink %s to make room for directory",
321 if (statret != 0 && do_mkdir(fname,file->mode) != 0 && errno != EEXIST) {
322 if (!(relative_paths && errno == ENOENT
323 && create_directory_path(fname, orig_umask) == 0
324 && do_mkdir(fname, file->mode) == 0)) {
325 rsyserr(FERROR, errno,
326 "recv_generator: mkdir %s failed",
330 /* f_out is set to -1 when doing final directory-permission
331 * and modification-time repair. */
332 if (set_perms(fname, file, statret ? NULL : &st, 0)
333 && verbose && f_out != -1)
334 rprintf(FINFO,"%s/\n",fname);
338 if (preserve_links && S_ISLNK(file->mode)) {
340 char lnk[MAXPATHLEN];
343 if (safe_symlinks && unsafe_symlink(file->u.link, fname)) {
345 rprintf(FINFO, "ignoring unsafe symlink %s -> \"%s\"\n",
346 full_fname(fname), file->u.link);
351 l = readlink(fname,lnk,MAXPATHLEN-1);
354 /* A link already pointing to the
355 * right place -- no further action
357 if (strcmp(lnk,file->u.link) == 0) {
358 set_perms(fname, file, &st,
363 /* Not a symlink, so delete whatever's
364 * already there and put a new symlink
368 if (do_symlink(file->u.link,fname) != 0) {
369 rsyserr(FERROR, errno, "symlink %s -> \"%s\" failed",
370 full_fname(fname), file->u.link);
372 set_perms(fname,file,NULL,0);
374 rprintf(FINFO,"%s -> %s\n", fname,file->u.link);
382 if (am_root && preserve_devices && IS_DEVICE(file->mode)) {
384 st.st_mode != file->mode ||
385 st.st_rdev != file->u.rdev) {
388 rprintf(FINFO,"mknod(%s,0%o,0x%x)\n",
389 fname,(int)file->mode,(int)file->u.rdev);
391 if (do_mknod(fname,file->mode,file->u.rdev) != 0) {
392 rsyserr(FERROR, errno, "mknod %s failed",
395 set_perms(fname,file,NULL,0);
397 rprintf(FINFO,"%s\n",fname);
400 set_perms(fname, file, &st, PERMS_REPORT);
406 if (preserve_hard_links && hard_link_check(file, HL_CHECK_MASTER))
409 if (!S_ISREG(file->mode)) {
410 rprintf(FINFO, "skipping non-regular file \"%s\"\n",fname);
416 if (statret == -1 && compare_dest != NULL) {
417 /* try the file at compare_dest instead */
418 int saveerrno = errno;
419 pathjoin(fnamecmpbuf, sizeof fnamecmpbuf, compare_dest, fname);
420 statret = link_stat(fnamecmpbuf, &st, 0);
421 if (!S_ISREG(st.st_mode))
426 else if (link_dest && !dry_run) {
427 if (do_link(fnamecmpbuf, fname) != 0) {
429 rsyserr(FINFO, errno, "link %s => %s",
433 fnamecmp = fnamecmpbuf;
437 fnamecmp = fnamecmpbuf;
441 if (preserve_hard_links && hard_link_check(file, HL_SKIP))
443 if (errno == ENOENT) {
445 if (!dry_run && !read_batch)
446 write_sum_head(f_out, NULL);
447 } else if (verbose > 1) {
448 rsyserr(FERROR, errno,
449 "recv_generator: failed to open %s",
455 if (!S_ISREG(st.st_mode)) {
456 if (delete_file(fname) != 0) {
460 /* now pretend the file didn't exist */
461 if (preserve_hard_links && hard_link_check(file, HL_SKIP))
464 if (!dry_run && !read_batch)
465 write_sum_head(f_out, NULL);
469 if (opt_ignore_existing && fnamecmp == fname) {
471 rprintf(FINFO,"%s exists\n",fname);
475 if (update_only && fnamecmp == fname
476 && cmp_modtime(st.st_mtime, file->modtime) > 0) {
478 rprintf(FINFO,"%s is newer\n",fname);
482 if (skip_file(fname, file, &st)) {
483 if (fnamecmp == fname)
484 set_perms(fname, file, &st, PERMS_REPORT);
488 if (dry_run || read_batch) {
493 if (whole_file > 0) {
495 write_sum_head(f_out, NULL);
500 fd = do_open(fnamecmp, O_RDONLY, 0);
503 rsyserr(FERROR, errno, "failed to open %s, continuing",
504 full_fname(fnamecmp));
505 /* pretend the file didn't exist */
506 if (preserve_hard_links && hard_link_check(file, HL_SKIP))
509 write_sum_head(f_out, NULL);
514 rprintf(FINFO,"gen mapped %s of size %.0f\n", fnamecmp,
519 rprintf(FINFO, "generating and sending sums for %d\n", i);
522 generate_and_send_sums(fd, st.st_size, f_out);
528 void generate_files(int f_out, struct file_list *flist, char *local_name)
532 char fbuf[MAXPATHLEN];
535 rprintf(FINFO, "generator starting pid=%ld count=%d\n",
536 (long)getpid(), flist->count);
542 ? "delta-transmission disabled for local transfer or --whole-file\n"
543 : "delta transmission enabled\n");
546 /* we expect to just sit around now, so don't exit on a
547 timeout. If we really get a timeout then the other process should
551 for (i = 0; i < flist->count; i++) {
552 struct file_struct *file = flist->files[i];
553 struct file_struct copy;
557 /* we need to ensure that any directories we create have writeable
558 permissions initially so that we can create the files within
559 them. This is then fixed after the files are transferred */
560 if (!am_root && S_ISDIR(file->mode) && !(file->mode & S_IWUSR)) {
562 /* XXX: Could this be causing a problem on SCO? Perhaps their
563 * handling of permissions is strange? */
564 copy.mode |= S_IWUSR; /* user write */
568 recv_generator(local_name ? local_name : f_name_to(file, fbuf),
573 csum_length = SUM_LENGTH;
577 rprintf(FINFO,"generate_files phase=%d\n",phase);
579 write_int(f_out, -1);
581 /* files can cycle through the system more than once
582 * to catch initial checksum errors */
583 while ((i = get_redo_num()) != -1) {
584 struct file_struct *file = flist->files[i];
585 recv_generator(local_name ? local_name : f_name_to(file, fbuf),
591 rprintf(FINFO,"generate_files phase=%d\n",phase);
593 write_int(f_out, -1);
595 if (preserve_hard_links)
598 /* now we need to fix any directory permissions that were
599 * modified during the transfer */
600 for (i = 0; i < flist->count; i++) {
601 struct file_struct *file = flist->files[i];
602 if (!file->basename || !S_ISDIR(file->mode))
604 recv_generator(local_name ? local_name : f_name(file),
609 rprintf(FINFO,"generate_files finished\n");