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;
49 extern int read_batch;
50 extern int write_batch;
52 extern int only_existing;
53 extern int orig_umask;
54 extern int safe_symlinks;
55 extern unsigned int block_size;
57 extern struct exclude_list_struct server_exclude_list;
60 /* choose whether to skip a particular file */
61 static int skip_file(char *fname, struct file_struct *file, STRUCT_STAT *st)
63 if (st->st_size != file->length)
67 && (st->st_mode & CHMOD_BITS) != (file->mode & CHMOD_BITS))
70 if (am_root && preserve_uid && st->st_uid != file->uid)
73 if (preserve_gid && file->gid != GID_NONE
74 && st->st_gid != file->gid)
78 /* if always checksum is set then we use the checksum instead
79 of the file time to determine whether to sync */
80 if (always_checksum && S_ISREG(st->st_mode)) {
81 char sum[MD4_SUM_LENGTH];
82 char fnamecmpdest[MAXPATHLEN];
84 if (compare_dest != NULL) {
85 if (access(fname, 0) != 0) {
86 pathjoin(fnamecmpdest, sizeof fnamecmpdest,
91 file_checksum(fname,sum,st->st_size);
92 return memcmp(sum, file->u.sum, protocol_version < 21 ? 2
93 : MD4_SUM_LENGTH) == 0;
102 return cmp_modtime(st->st_mtime, file->modtime) == 0;
107 * NULL sum_struct means we have no checksums
109 void write_sum_head(int f, struct sum_struct *sum)
111 static struct sum_struct null_sum;
116 write_int(f, sum->count);
117 write_int(f, sum->blength);
118 if (protocol_version >= 27)
119 write_int(f, sum->s2length);
120 write_int(f, sum->remainder);
124 * set (initialize) the size entries in the per-file sum_struct
125 * calculating dynamic block and checksum sizes.
127 * This is only called from generate_and_send_sums() but is a separate
128 * function to encapsulate the logic.
130 * The block size is a rounded square root of file length.
132 * The checksum size is determined according to:
133 * blocksum_bits = BLOCKSUM_EXP + 2*log2(file_len) - log2(block_len)
134 * provided by Donovan Baarda which gives a probability of rsync
135 * algorithm corrupting data and falling back using the whole md4
138 * This might be made one of several selectable heuristics.
141 static void sum_sizes_sqroot(struct sum_struct *sum, uint64 len)
143 unsigned int blength;
149 blength = block_size;
150 } else if (len <= BLOCK_SIZE * BLOCK_SIZE) {
151 blength = BLOCK_SIZE;
161 if (len < (uint64)blength * blength)
164 } while (c >= 8); /* round to multiple of 8 */
165 blength = MAX(blength, BLOCK_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);
205 * Perhaps we want to just send an empty checksum set for this file,
206 * which will force the whole thing to be literally transferred.
208 * When do we do this? If the user's explicitly said they
209 * want the whole thing, or if { they haven't explicitly
210 * requested a delta, and it's local but not batch mode.}
213 static BOOL disable_deltas_p(void)
217 if (whole_file == 0 || write_batch || read_batch)
224 * Generate and send a stream of signatures/checksums that describe a buffer
226 * Generate approximately one checksum every block_len bytes.
228 static void generate_and_send_sums(struct map_struct *buf, size_t len, int f_out)
231 struct sum_struct sum;
234 sum_sizes_sqroot(&sum, len);
236 write_sum_head(f_out, &sum);
238 for (i = 0; i < sum.count; i++) {
239 unsigned int n1 = MIN(len, sum.blength);
240 char *map = map_ptr(buf, offset, n1);
241 uint32 sum1 = get_checksum1(map, n1);
242 char sum2[SUM_LENGTH];
244 get_checksum2(map, n1, sum2);
248 "chunk[%.0f] offset=%.0f len=%u sum1=%08lx\n",
249 (double)i, (double)offset, n1,
250 (unsigned long)sum1);
252 write_int(f_out, sum1);
253 write_buf(f_out, sum2, sum.s2length);
262 * Acts on file number @p i from @p flist, whose name is @p fname.
264 * First fixes up permissions, then generates checksums for the file.
266 * @note This comment was added later by mbp who was trying to work it
267 * out. It might be wrong.
269 void recv_generator(char *fname, struct file_struct *file, int i, int f_out)
273 struct map_struct *mapbuf;
276 char fnamecmpbuf[MAXPATHLEN];
282 rprintf(FINFO,"recv_generator(%s,%d)\n",fname,i);
284 if (server_exclude_list.head
285 && check_exclude(&server_exclude_list, fname,
286 S_ISDIR(file->mode)) < 0) {
288 rprintf(FINFO, "skipping server-excluded file \"%s\"\n",
294 statret = link_stat(fname, &st, keep_dirlinks && S_ISDIR(file->mode));
296 if (only_existing && statret == -1 && errno == ENOENT) {
297 /* we only want to update existing files */
299 rprintf(FINFO, "not creating new file \"%s\"\n", fname);
305 (S_ISDIR(st.st_mode) == S_ISDIR(file->mode))) {
306 /* if the file exists already and we aren't perserving
307 * permissions then act as though the remote end sent
308 * us the file permissions we already have */
309 file->mode = (file->mode & ~CHMOD_BITS)
310 | (st.st_mode & CHMOD_BITS);
313 if (S_ISDIR(file->mode)) {
314 /* The file to be received is a directory, so we need
315 * to prepare appropriately. If there is already a
316 * file of that name and it is *not* a directory, then
317 * we need to delete it. If it doesn't exist, then
318 * recursively create it. */
321 return; /* TODO: causes inaccuracies -- fix */
322 if (statret == 0 && !S_ISDIR(st.st_mode)) {
323 if (robust_unlink(fname) != 0) {
324 rsyserr(FERROR, errno,
325 "recv_generator: unlink %s to make room for directory",
331 if (statret != 0 && do_mkdir(fname,file->mode) != 0 && errno != EEXIST) {
332 if (!(relative_paths && errno == ENOENT
333 && create_directory_path(fname, orig_umask) == 0
334 && do_mkdir(fname, file->mode) == 0)) {
335 rsyserr(FERROR, errno,
336 "recv_generator: mkdir %s failed",
340 /* f_out is set to -1 when doing final directory-permission
341 * and modification-time repair. */
342 if (set_perms(fname, file, statret ? NULL : &st, 0)
343 && verbose && f_out != -1)
344 rprintf(FINFO,"%s/\n",fname);
348 if (preserve_links && S_ISLNK(file->mode)) {
350 char lnk[MAXPATHLEN];
353 if (safe_symlinks && unsafe_symlink(file->u.link, fname)) {
355 rprintf(FINFO, "ignoring unsafe symlink %s -> \"%s\"\n",
356 full_fname(fname), file->u.link);
361 l = readlink(fname,lnk,MAXPATHLEN-1);
364 /* A link already pointing to the
365 * right place -- no further action
367 if (strcmp(lnk,file->u.link) == 0) {
368 set_perms(fname, file, &st,
373 /* Not a symlink, so delete whatever's
374 * already there and put a new symlink
378 if (do_symlink(file->u.link,fname) != 0) {
379 rsyserr(FERROR, errno, "symlink %s -> \"%s\" failed",
380 full_fname(fname), file->u.link);
382 set_perms(fname,file,NULL,0);
384 rprintf(FINFO,"%s -> %s\n", fname,file->u.link);
392 if (am_root && preserve_devices && IS_DEVICE(file->mode)) {
394 st.st_mode != file->mode ||
395 st.st_rdev != file->u.rdev) {
398 rprintf(FINFO,"mknod(%s,0%o,0x%x)\n",
399 fname,(int)file->mode,(int)file->u.rdev);
401 if (do_mknod(fname,file->mode,file->u.rdev) != 0) {
402 rsyserr(FERROR, errno, "mknod %s failed",
405 set_perms(fname,file,NULL,0);
407 rprintf(FINFO,"%s\n",fname);
410 set_perms(fname, file, &st, PERMS_REPORT);
416 if (preserve_hard_links && hard_link_check(file, HL_CHECK_MASTER))
419 if (!S_ISREG(file->mode)) {
420 rprintf(FINFO, "skipping non-regular file \"%s\"\n",fname);
426 if (statret == -1 && compare_dest != NULL) {
427 /* try the file at compare_dest instead */
428 int saveerrno = errno;
429 pathjoin(fnamecmpbuf, sizeof fnamecmpbuf, compare_dest, fname);
430 statret = link_stat(fnamecmpbuf, &st, 0);
431 if (!S_ISREG(st.st_mode))
436 else if (link_dest && !dry_run) {
437 if (do_link(fnamecmpbuf, fname) != 0) {
439 rsyserr(FINFO, errno, "link %s => %s",
443 fnamecmp = fnamecmpbuf;
447 fnamecmp = fnamecmpbuf;
451 if (preserve_hard_links && hard_link_check(file, HL_SKIP))
453 if (errno == ENOENT) {
456 write_sum_head(f_out, NULL);
457 } else if (verbose > 1) {
458 rsyserr(FERROR, errno,
459 "recv_generator: failed to open %s",
465 if (!S_ISREG(st.st_mode)) {
466 if (delete_file(fname) != 0) {
470 /* now pretend the file didn't exist */
471 if (preserve_hard_links && hard_link_check(file, HL_SKIP))
475 write_sum_head(f_out, NULL);
479 if (opt_ignore_existing && fnamecmp == fname) {
481 rprintf(FINFO,"%s exists\n",fname);
485 if (update_only && fnamecmp == fname
486 && cmp_modtime(st.st_mtime, file->modtime) > 0) {
488 rprintf(FINFO,"%s is newer\n",fname);
492 if (skip_file(fname, file, &st)) {
493 if (fnamecmp == fname)
494 set_perms(fname, file, &st, PERMS_REPORT);
503 if (disable_deltas_p()) {
505 write_sum_head(f_out, NULL);
510 fd = do_open(fnamecmp, O_RDONLY, 0);
513 rsyserr(FERROR, errno, "failed to open %s, continuing",
514 full_fname(fnamecmp));
515 /* pretend the file didn't exist */
516 if (preserve_hard_links && hard_link_check(file, HL_SKIP))
519 write_sum_head(f_out, NULL);
524 mapbuf = map_file(fd,st.st_size);
529 rprintf(FINFO,"gen mapped %s of size %.0f\n", fnamecmp,
534 rprintf(FINFO, "generating and sending sums for %d\n", i);
537 generate_and_send_sums(mapbuf, st.st_size, f_out);
545 void generate_files(int f, struct file_list *flist, char *local_name)
549 char fbuf[MAXPATHLEN];
552 rprintf(FINFO, "generator starting pid=%ld count=%d\n",
553 (long)getpid(), flist->count);
559 ? "delta-transmission disabled for local transfer or --whole-file\n"
560 : "delta transmission enabled\n");
563 /* we expect to just sit around now, so don't exit on a
564 timeout. If we really get a timeout then the other process should
568 for (i = 0; i < flist->count; i++) {
569 struct file_struct *file = flist->files[i];
570 struct file_struct copy;
574 /* we need to ensure that any directories we create have writeable
575 permissions initially so that we can create the files within
576 them. This is then fixed after the files are transferred */
577 if (!am_root && S_ISDIR(file->mode) && !(file->mode & S_IWUSR)) {
579 /* XXX: Could this be causing a problem on SCO? Perhaps their
580 * handling of permissions is strange? */
581 copy.mode |= S_IWUSR; /* user write */
585 recv_generator(local_name ? local_name : f_name_to(file, fbuf),
590 csum_length = SUM_LENGTH;
594 rprintf(FINFO,"generate_files phase=%d\n",phase);
598 /* files can cycle through the system more than once
599 * to catch initial checksum errors */
600 while ((i = get_redo_num()) != -1) {
601 struct file_struct *file = flist->files[i];
602 recv_generator(local_name ? local_name : f_name_to(file, fbuf),
608 rprintf(FINFO,"generate_files phase=%d\n",phase);
612 if (preserve_hard_links)
615 /* now we need to fix any directory permissions that were
616 * modified during the transfer */
617 for (i = 0; i < flist->count; i++) {
618 struct file_struct *file = flist->files[i];
619 if (!file->basename || !S_ISDIR(file->mode))
621 recv_generator(local_name ? local_name : f_name(file),
626 rprintf(FINFO,"generate_files finished\n");