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", safe_fname(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",
296 if (statret == 0 && !preserve_perms
297 && S_ISDIR(st.st_mode) == S_ISDIR(file->mode)) {
298 /* if the file exists already and we aren't perserving
299 * permissions then act as though the remote end sent
300 * us the file permissions we already have */
301 file->mode = (file->mode & ~CHMOD_BITS)
302 | (st.st_mode & CHMOD_BITS);
305 if (S_ISDIR(file->mode)) {
306 /* The file to be received is a directory, so we need
307 * to prepare appropriately. If there is already a
308 * file of that name and it is *not* a directory, then
309 * we need to delete it. If it doesn't exist, then
310 * recursively create it. */
313 return; /* TODO: causes inaccuracies -- fix */
314 if (statret == 0 && !S_ISDIR(st.st_mode)) {
315 if (robust_unlink(fname) != 0) {
316 rsyserr(FERROR, errno,
317 "recv_generator: unlink %s to make room for directory",
323 if (statret != 0 && do_mkdir(fname,file->mode) != 0 && errno != EEXIST) {
324 if (!(relative_paths && errno == ENOENT
325 && create_directory_path(fname, orig_umask) == 0
326 && do_mkdir(fname, file->mode) == 0)) {
327 rsyserr(FERROR, errno,
328 "recv_generator: mkdir %s failed",
332 /* f_out is set to -1 when doing final directory-permission
333 * and modification-time repair. */
334 if (set_perms(fname, file, statret ? NULL : &st, 0)
335 && verbose && f_out != -1)
336 rprintf(FINFO, "%s/\n", safe_fname(fname));
340 if (preserve_links && S_ISLNK(file->mode)) {
342 char lnk[MAXPATHLEN];
345 if (safe_symlinks && unsafe_symlink(file->u.link, fname)) {
347 rprintf(FINFO, "ignoring unsafe symlink %s -> \"%s\"\n",
348 full_fname(fname), file->u.link);
353 l = readlink(fname,lnk,MAXPATHLEN-1);
356 /* A link already pointing to the
357 * right place -- no further action
359 if (strcmp(lnk,file->u.link) == 0) {
360 set_perms(fname, file, &st,
365 /* Not a symlink, so delete whatever's
366 * already there and put a new symlink
370 if (do_symlink(file->u.link,fname) != 0) {
371 rsyserr(FERROR, errno, "symlink %s -> \"%s\" failed",
372 full_fname(fname), safe_fname(file->u.link));
374 set_perms(fname,file,NULL,0);
376 rprintf(FINFO, "%s -> %s\n", safe_fname(fname),
377 safe_fname(file->u.link));
385 if (am_root && preserve_devices && IS_DEVICE(file->mode)) {
387 st.st_mode != file->mode ||
388 st.st_rdev != file->u.rdev) {
391 rprintf(FINFO,"mknod(%s,0%o,0x%x)\n",
393 (int)file->mode, (int)file->u.rdev);
395 if (do_mknod(fname,file->mode,file->u.rdev) != 0) {
396 rsyserr(FERROR, errno, "mknod %s failed",
399 set_perms(fname,file,NULL,0);
401 rprintf(FINFO, "%s\n",
406 set_perms(fname, file, &st, PERMS_REPORT);
412 if (preserve_hard_links && hard_link_check(file, HL_CHECK_MASTER))
415 if (!S_ISREG(file->mode)) {
416 rprintf(FINFO, "skipping non-regular file \"%s\"\n",
423 if (statret == -1 && compare_dest != NULL) {
424 /* try the file at compare_dest instead */
425 int saveerrno = errno;
426 pathjoin(fnamecmpbuf, sizeof fnamecmpbuf, compare_dest, fname);
427 statret = link_stat(fnamecmpbuf, &st, 0);
428 if (!S_ISREG(st.st_mode))
433 else if (link_dest && !dry_run) {
434 if (do_link(fnamecmpbuf, fname) != 0) {
436 rsyserr(FINFO, errno, "link %s => %s",
437 fnamecmpbuf, safe_fname(fname));
440 fnamecmp = fnamecmpbuf;
444 fnamecmp = fnamecmpbuf;
448 if (preserve_hard_links && hard_link_check(file, HL_SKIP))
450 if (errno == ENOENT) {
452 if (!dry_run && !read_batch)
453 write_sum_head(f_out, NULL);
454 } else if (verbose > 1) {
455 rsyserr(FERROR, errno,
456 "recv_generator: failed to open %s",
462 if (!S_ISREG(st.st_mode)) {
463 if (delete_file(fname) != 0) {
467 /* now pretend the file didn't exist */
468 if (preserve_hard_links && hard_link_check(file, HL_SKIP))
471 if (!dry_run && !read_batch)
472 write_sum_head(f_out, NULL);
476 if (opt_ignore_existing && fnamecmp == fname) {
478 rprintf(FINFO, "%s exists\n", safe_fname(fname));
482 if (update_only && fnamecmp == fname
483 && cmp_modtime(st.st_mtime, file->modtime) > 0) {
485 rprintf(FINFO, "%s is newer\n", safe_fname(fname));
489 if (skip_file(fname, file, &st)) {
490 if (fnamecmp == fname)
491 set_perms(fname, file, &st, PERMS_REPORT);
495 if (dry_run || read_batch) {
500 if (whole_file > 0) {
502 write_sum_head(f_out, NULL);
507 fd = do_open(fnamecmp, O_RDONLY, 0);
510 rsyserr(FERROR, errno, "failed to open %s, continuing",
511 full_fname(fnamecmp));
512 /* pretend the file didn't exist */
513 if (preserve_hard_links && hard_link_check(file, HL_SKIP))
516 write_sum_head(f_out, NULL);
521 rprintf(FINFO, "gen mapped %s of size %.0f\n",
522 safe_fname(fnamecmp), (double)st.st_size);
526 rprintf(FINFO, "generating and sending sums for %d\n", i);
529 generate_and_send_sums(fd, st.st_size, f_out);
535 void generate_files(int f_out, struct file_list *flist, char *local_name)
539 char fbuf[MAXPATHLEN];
542 rprintf(FINFO, "generator starting pid=%ld count=%d\n",
543 (long)getpid(), flist->count);
549 ? "delta-transmission disabled for local transfer or --whole-file\n"
550 : "delta transmission enabled\n");
553 /* we expect to just sit around now, so don't exit on a
554 timeout. If we really get a timeout then the other process should
558 for (i = 0; i < flist->count; i++) {
559 struct file_struct *file = flist->files[i];
560 struct file_struct copy;
564 /* we need to ensure that any directories we create have writeable
565 permissions initially so that we can create the files within
566 them. This is then fixed after the files are transferred */
567 if (!am_root && S_ISDIR(file->mode) && !(file->mode & S_IWUSR)) {
569 /* XXX: Could this be causing a problem on SCO? Perhaps their
570 * handling of permissions is strange? */
571 copy.mode |= S_IWUSR; /* user write */
575 recv_generator(local_name ? local_name : f_name_to(file, fbuf),
580 csum_length = SUM_LENGTH;
584 rprintf(FINFO,"generate_files phase=%d\n",phase);
586 write_int(f_out, -1);
588 /* files can cycle through the system more than once
589 * to catch initial checksum errors */
590 while ((i = get_redo_num()) != -1) {
591 struct file_struct *file = flist->files[i];
592 recv_generator(local_name ? local_name : f_name_to(file, fbuf),
598 rprintf(FINFO,"generate_files phase=%d\n",phase);
600 write_int(f_out, -1);
602 if (preserve_hard_links)
605 /* now we need to fix any directory permissions that were
606 * modified during the transfer */
607 for (i = 0; i < flist->count; i++) {
608 struct file_struct *file = flist->files[i];
609 if (!file->basename || !S_ISDIR(file->mode))
611 recv_generator(local_name ? local_name : f_name(file),
616 rprintf(FINFO,"generate_files finished\n");