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);
167 if (protocol_version < 27) {
168 s2length = csum_length;
169 } else if (csum_length == SUM_LENGTH) {
170 s2length = SUM_LENGTH;
172 int b = BLOCKSUM_BIAS;
178 while (c >>= 1 && b) {
181 s2length = (b + 1 - 32 + 7) / 8; /* add a bit,
184 * --optimize in compiler--
186 s2length = MAX(s2length, csum_length);
187 s2length = MIN(s2length, SUM_LENGTH);
191 sum->blength = blength;
192 sum->s2length = s2length;
193 sum->count = (len + (blength - 1)) / blength;
194 sum->remainder = (len % blength);
196 if (sum->count && verbose > 2) {
197 rprintf(FINFO, "count=%.0f rem=%u blength=%u s2length=%d flength=%.0f\n",
198 (double)sum->count, sum->remainder, sum->blength,
199 sum->s2length, (double)sum->flength);
205 * Generate and send a stream of signatures/checksums that describe a buffer
207 * Generate approximately one checksum every block_len bytes.
209 static void generate_and_send_sums(struct map_struct *buf, OFF_T len, int f_out)
212 struct sum_struct sum;
215 sum_sizes_sqroot(&sum, len);
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(buf, offset, n1);
222 uint32 sum1 = get_checksum1(map, n1);
223 char sum2[SUM_LENGTH];
225 get_checksum2(map, n1, sum2);
229 "chunk[%.0f] offset=%.0f len=%u sum1=%08lx\n",
230 (double)i, (double)offset, n1,
231 (unsigned long)sum1);
233 write_int(f_out, sum1);
234 write_buf(f_out, sum2, sum.s2length);
243 * Acts on file number @p i from @p flist, whose name is @p fname.
245 * First fixes up permissions, then generates checksums for the file.
247 * @note This comment was added later by mbp who was trying to work it
248 * out. It might be wrong.
250 static void recv_generator(char *fname, struct file_struct *file, int i,
255 struct map_struct *mapbuf;
258 char fnamecmpbuf[MAXPATHLEN];
264 rprintf(FINFO,"recv_generator(%s,%d)\n",fname,i);
266 if (server_exclude_list.head
267 && check_exclude(&server_exclude_list, fname,
268 S_ISDIR(file->mode)) < 0) {
270 rprintf(FINFO, "skipping server-excluded file \"%s\"\n",
276 statret = link_stat(fname, &st, keep_dirlinks && S_ISDIR(file->mode));
278 if (only_existing && statret == -1 && errno == ENOENT) {
279 /* we only want to update existing files */
281 rprintf(FINFO, "not creating new file \"%s\"\n", fname);
287 (S_ISDIR(st.st_mode) == S_ISDIR(file->mode))) {
288 /* if the file exists already and we aren't perserving
289 * permissions then act as though the remote end sent
290 * us the file permissions we already have */
291 file->mode = (file->mode & ~CHMOD_BITS)
292 | (st.st_mode & CHMOD_BITS);
295 if (S_ISDIR(file->mode)) {
296 /* The file to be received is a directory, so we need
297 * to prepare appropriately. If there is already a
298 * file of that name and it is *not* a directory, then
299 * we need to delete it. If it doesn't exist, then
300 * recursively create it. */
303 return; /* TODO: causes inaccuracies -- fix */
304 if (statret == 0 && !S_ISDIR(st.st_mode)) {
305 if (robust_unlink(fname) != 0) {
306 rsyserr(FERROR, errno,
307 "recv_generator: unlink %s to make room for directory",
313 if (statret != 0 && do_mkdir(fname,file->mode) != 0 && errno != EEXIST) {
314 if (!(relative_paths && errno == ENOENT
315 && create_directory_path(fname, orig_umask) == 0
316 && do_mkdir(fname, file->mode) == 0)) {
317 rsyserr(FERROR, errno,
318 "recv_generator: mkdir %s failed",
322 /* f_out is set to -1 when doing final directory-permission
323 * and modification-time repair. */
324 if (set_perms(fname, file, statret ? NULL : &st, 0)
325 && verbose && f_out != -1)
326 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);
401 if (preserve_hard_links && hard_link_check(file, HL_CHECK_MASTER))
404 if (!S_ISREG(file->mode)) {
405 rprintf(FINFO, "skipping non-regular file \"%s\"\n",fname);
411 if (statret == -1 && compare_dest != NULL) {
412 /* try the file at compare_dest instead */
413 int saveerrno = errno;
414 pathjoin(fnamecmpbuf, sizeof fnamecmpbuf, compare_dest, fname);
415 statret = link_stat(fnamecmpbuf, &st, 0);
416 if (!S_ISREG(st.st_mode))
421 else if (link_dest && !dry_run) {
422 if (do_link(fnamecmpbuf, fname) != 0) {
424 rsyserr(FINFO, errno, "link %s => %s",
428 fnamecmp = fnamecmpbuf;
432 fnamecmp = fnamecmpbuf;
436 if (preserve_hard_links && hard_link_check(file, HL_SKIP))
438 if (errno == ENOENT) {
441 write_sum_head(f_out, NULL);
442 } else if (verbose > 1) {
443 rsyserr(FERROR, errno,
444 "recv_generator: failed to open %s",
450 if (!S_ISREG(st.st_mode)) {
451 if (delete_file(fname) != 0) {
455 /* now pretend the file didn't exist */
456 if (preserve_hard_links && hard_link_check(file, HL_SKIP))
460 write_sum_head(f_out, NULL);
464 if (opt_ignore_existing && fnamecmp == fname) {
466 rprintf(FINFO,"%s exists\n",fname);
470 if (update_only && fnamecmp == fname
471 && cmp_modtime(st.st_mtime, file->modtime) > 0) {
473 rprintf(FINFO,"%s is newer\n",fname);
477 if (skip_file(fname, file, &st)) {
478 if (fnamecmp == fname)
479 set_perms(fname, file, &st, PERMS_REPORT);
488 if (whole_file > 0) {
490 write_sum_head(f_out, NULL);
495 fd = do_open(fnamecmp, O_RDONLY, 0);
498 rsyserr(FERROR, errno, "failed to open %s, continuing",
499 full_fname(fnamecmp));
500 /* pretend the file didn't exist */
501 if (preserve_hard_links && hard_link_check(file, HL_SKIP))
504 write_sum_head(f_out, NULL);
509 mapbuf = map_file(fd,st.st_size);
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(mapbuf, st.st_size, f_out);
530 void generate_files(int f_out, struct file_list *flist, char *local_name)
534 char fbuf[MAXPATHLEN];
537 rprintf(FINFO, "generator starting pid=%ld count=%d\n",
538 (long)getpid(), flist->count);
544 ? "delta-transmission disabled for local transfer or --whole-file\n"
545 : "delta transmission enabled\n");
548 /* we expect to just sit around now, so don't exit on a
549 timeout. If we really get a timeout then the other process should
553 for (i = 0; i < flist->count; i++) {
554 struct file_struct *file = flist->files[i];
555 struct file_struct copy;
559 /* we need to ensure that any directories we create have writeable
560 permissions initially so that we can create the files within
561 them. This is then fixed after the files are transferred */
562 if (!am_root && S_ISDIR(file->mode) && !(file->mode & S_IWUSR)) {
564 /* XXX: Could this be causing a problem on SCO? Perhaps their
565 * handling of permissions is strange? */
566 copy.mode |= S_IWUSR; /* user write */
570 recv_generator(local_name ? local_name : f_name_to(file, fbuf),
575 csum_length = SUM_LENGTH;
579 rprintf(FINFO,"generate_files phase=%d\n",phase);
581 write_int(f_out, -1);
583 /* files can cycle through the system more than once
584 * to catch initial checksum errors */
585 while ((i = get_redo_num()) != -1) {
586 struct file_struct *file = flist->files[i];
587 recv_generator(local_name ? local_name : f_name_to(file, fbuf),
593 rprintf(FINFO,"generate_files phase=%d\n",phase);
595 write_int(f_out, -1);
597 if (preserve_hard_links)
600 /* now we need to fix any directory permissions that were
601 * modified during the transfer */
602 for (i = 0; i < flist->count; i++) {
603 struct file_struct *file = flist->files[i];
604 if (!file->basename || !S_ISDIR(file->mode))
606 recv_generator(local_name ? local_name : f_name(file),
611 rprintf(FINFO,"generate_files finished\n");