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 only_existing;
51 extern int orig_umask;
52 extern int safe_symlinks;
53 extern unsigned int block_size;
55 extern struct exclude_list_struct server_exclude_list;
58 /* choose whether to skip a particular file */
59 static int skip_file(char *fname, struct file_struct *file, STRUCT_STAT *st)
61 if (st->st_size != file->length)
65 && (st->st_mode & CHMOD_BITS) != (file->mode & CHMOD_BITS))
68 if (am_root && preserve_uid && st->st_uid != file->uid)
71 if (preserve_gid && file->gid != GID_NONE
72 && st->st_gid != file->gid)
76 /* if always checksum is set then we use the checksum instead
77 of the file time to determine whether to sync */
78 if (always_checksum && S_ISREG(st->st_mode)) {
79 char sum[MD4_SUM_LENGTH];
80 char fnamecmpdest[MAXPATHLEN];
82 if (compare_dest != NULL) {
83 if (access(fname, 0) != 0) {
84 pathjoin(fnamecmpdest, sizeof fnamecmpdest,
89 file_checksum(fname,sum,st->st_size);
90 return memcmp(sum, file->u.sum, protocol_version < 21 ? 2
91 : MD4_SUM_LENGTH) == 0;
100 return cmp_modtime(st->st_mtime, file->modtime) == 0;
105 * NULL sum_struct means we have no checksums
107 void write_sum_head(int f, struct sum_struct *sum)
109 static struct sum_struct null_sum;
114 write_int(f, sum->count);
115 write_int(f, sum->blength);
116 if (protocol_version >= 27)
117 write_int(f, sum->s2length);
118 write_int(f, sum->remainder);
122 * set (initialize) the size entries in the per-file sum_struct
123 * calculating dynamic block and checksum sizes.
125 * This is only called from generate_and_send_sums() but is a separate
126 * function to encapsulate the logic.
128 * The block size is a rounded square root of file length.
130 * The checksum size is determined according to:
131 * blocksum_bits = BLOCKSUM_EXP + 2*log2(file_len) - log2(block_len)
132 * provided by Donovan Baarda which gives a probability of rsync
133 * algorithm corrupting data and falling back using the whole md4
136 * This might be made one of several selectable heuristics.
139 static void sum_sizes_sqroot(struct sum_struct *sum, uint64 len)
141 unsigned int blength;
147 blength = block_size;
148 } else if (len <= BLOCK_SIZE * BLOCK_SIZE) {
149 blength = BLOCK_SIZE;
159 if (len < (uint64)blength * blength)
162 } while (c >= 8); /* round to multiple of 8 */
163 blength = MAX(blength, BLOCK_SIZE);
166 if (protocol_version < 27) {
167 s2length = csum_length;
168 } else if (csum_length == SUM_LENGTH) {
169 s2length = SUM_LENGTH;
171 int b = BLOCKSUM_BIAS;
177 while (c >>= 1 && b) {
180 s2length = (b + 1 - 32 + 7) / 8; /* add a bit,
183 * --optimize in compiler--
185 s2length = MAX(s2length, csum_length);
186 s2length = MIN(s2length, SUM_LENGTH);
190 sum->blength = blength;
191 sum->s2length = s2length;
192 sum->count = (len + (blength - 1)) / blength;
193 sum->remainder = (len % blength);
195 if (sum->count && verbose > 2) {
196 rprintf(FINFO, "count=%.0f rem=%u blength=%u s2length=%d flength=%.0f\n",
197 (double)sum->count, sum->remainder, sum->blength,
198 sum->s2length, (double)sum->flength);
204 * Generate and send a stream of signatures/checksums that describe a buffer
206 * Generate approximately one checksum every block_len bytes.
208 static void generate_and_send_sums(struct map_struct *buf, OFF_T len, int f_out)
211 struct sum_struct sum;
214 sum_sizes_sqroot(&sum, len);
216 write_sum_head(f_out, &sum);
218 for (i = 0; i < sum.count; i++) {
219 unsigned int n1 = MIN(len, sum.blength);
220 char *map = map_ptr(buf, offset, n1);
221 uint32 sum1 = get_checksum1(map, n1);
222 char sum2[SUM_LENGTH];
224 get_checksum2(map, n1, sum2);
228 "chunk[%.0f] offset=%.0f len=%u sum1=%08lx\n",
229 (double)i, (double)offset, n1,
230 (unsigned long)sum1);
232 write_int(f_out, sum1);
233 write_buf(f_out, sum2, sum.s2length);
242 * Acts on file number @p i from @p flist, whose name is @p fname.
244 * First fixes up permissions, then generates checksums for the file.
246 * @note This comment was added later by mbp who was trying to work it
247 * out. It might be wrong.
249 static void recv_generator(char *fname, struct file_struct *file, int i,
254 struct map_struct *mapbuf;
257 char fnamecmpbuf[MAXPATHLEN];
263 rprintf(FINFO,"recv_generator(%s,%d)\n",fname,i);
265 if (server_exclude_list.head
266 && check_exclude(&server_exclude_list, fname,
267 S_ISDIR(file->mode)) < 0) {
269 rprintf(FINFO, "skipping server-excluded file \"%s\"\n",
275 statret = link_stat(fname, &st, keep_dirlinks && S_ISDIR(file->mode));
277 if (only_existing && statret == -1 && errno == ENOENT) {
278 /* we only want to update existing files */
280 rprintf(FINFO, "not creating new file \"%s\"\n", fname);
286 (S_ISDIR(st.st_mode) == S_ISDIR(file->mode))) {
287 /* if the file exists already and we aren't perserving
288 * permissions then act as though the remote end sent
289 * us the file permissions we already have */
290 file->mode = (file->mode & ~CHMOD_BITS)
291 | (st.st_mode & CHMOD_BITS);
294 if (S_ISDIR(file->mode)) {
295 /* The file to be received is a directory, so we need
296 * to prepare appropriately. If there is already a
297 * file of that name and it is *not* a directory, then
298 * we need to delete it. If it doesn't exist, then
299 * recursively create it. */
302 return; /* TODO: causes inaccuracies -- fix */
303 if (statret == 0 && !S_ISDIR(st.st_mode)) {
304 if (robust_unlink(fname) != 0) {
305 rsyserr(FERROR, errno,
306 "recv_generator: unlink %s to make room for directory",
312 if (statret != 0 && do_mkdir(fname,file->mode) != 0 && errno != EEXIST) {
313 if (!(relative_paths && errno == ENOENT
314 && create_directory_path(fname, orig_umask) == 0
315 && do_mkdir(fname, file->mode) == 0)) {
316 rsyserr(FERROR, errno,
317 "recv_generator: mkdir %s failed",
321 /* f_out is set to -1 when doing final directory-permission
322 * and modification-time repair. */
323 if (set_perms(fname, file, statret ? NULL : &st, 0)
324 && verbose && f_out != -1)
325 rprintf(FINFO,"%s/\n",fname);
329 if (preserve_links && S_ISLNK(file->mode)) {
331 char lnk[MAXPATHLEN];
334 if (safe_symlinks && unsafe_symlink(file->u.link, fname)) {
336 rprintf(FINFO, "ignoring unsafe symlink %s -> \"%s\"\n",
337 full_fname(fname), file->u.link);
342 l = readlink(fname,lnk,MAXPATHLEN-1);
345 /* A link already pointing to the
346 * right place -- no further action
348 if (strcmp(lnk,file->u.link) == 0) {
349 set_perms(fname, file, &st,
354 /* Not a symlink, so delete whatever's
355 * already there and put a new symlink
359 if (do_symlink(file->u.link,fname) != 0) {
360 rsyserr(FERROR, errno, "symlink %s -> \"%s\" failed",
361 full_fname(fname), file->u.link);
363 set_perms(fname,file,NULL,0);
365 rprintf(FINFO,"%s -> %s\n", fname,file->u.link);
373 if (am_root && preserve_devices && IS_DEVICE(file->mode)) {
375 st.st_mode != file->mode ||
376 st.st_rdev != file->u.rdev) {
379 rprintf(FINFO,"mknod(%s,0%o,0x%x)\n",
380 fname,(int)file->mode,(int)file->u.rdev);
382 if (do_mknod(fname,file->mode,file->u.rdev) != 0) {
383 rsyserr(FERROR, errno, "mknod %s failed",
386 set_perms(fname,file,NULL,0);
388 rprintf(FINFO,"%s\n",fname);
391 set_perms(fname, file, &st, PERMS_REPORT);
397 if (preserve_hard_links && hard_link_check(file, HL_CHECK_MASTER))
400 if (!S_ISREG(file->mode)) {
401 rprintf(FINFO, "skipping non-regular file \"%s\"\n",fname);
407 if (statret == -1 && compare_dest != NULL) {
408 /* try the file at compare_dest instead */
409 int saveerrno = errno;
410 pathjoin(fnamecmpbuf, sizeof fnamecmpbuf, compare_dest, fname);
411 statret = link_stat(fnamecmpbuf, &st, 0);
412 if (!S_ISREG(st.st_mode))
417 else if (link_dest && !dry_run) {
418 if (do_link(fnamecmpbuf, fname) != 0) {
420 rsyserr(FINFO, errno, "link %s => %s",
424 fnamecmp = fnamecmpbuf;
428 fnamecmp = fnamecmpbuf;
432 if (preserve_hard_links && hard_link_check(file, HL_SKIP))
434 if (errno == ENOENT) {
437 write_sum_head(f_out, NULL);
438 } else if (verbose > 1) {
439 rsyserr(FERROR, errno,
440 "recv_generator: failed to open %s",
446 if (!S_ISREG(st.st_mode)) {
447 if (delete_file(fname) != 0) {
451 /* now pretend the file didn't exist */
452 if (preserve_hard_links && hard_link_check(file, HL_SKIP))
456 write_sum_head(f_out, NULL);
460 if (opt_ignore_existing && fnamecmp == fname) {
462 rprintf(FINFO,"%s exists\n",fname);
466 if (update_only && fnamecmp == fname
467 && cmp_modtime(st.st_mtime, file->modtime) > 0) {
469 rprintf(FINFO,"%s is newer\n",fname);
473 if (skip_file(fname, file, &st)) {
474 if (fnamecmp == fname)
475 set_perms(fname, file, &st, PERMS_REPORT);
484 if (whole_file > 0) {
486 write_sum_head(f_out, NULL);
491 fd = do_open(fnamecmp, O_RDONLY, 0);
494 rsyserr(FERROR, errno, "failed to open %s, continuing",
495 full_fname(fnamecmp));
496 /* pretend the file didn't exist */
497 if (preserve_hard_links && hard_link_check(file, HL_SKIP))
500 write_sum_head(f_out, NULL);
505 mapbuf = map_file(fd,st.st_size);
510 rprintf(FINFO,"gen mapped %s of size %.0f\n", fnamecmp,
515 rprintf(FINFO, "generating and sending sums for %d\n", i);
518 generate_and_send_sums(mapbuf, st.st_size, f_out);
526 void generate_files(int f_out, struct file_list *flist, char *local_name)
530 char fbuf[MAXPATHLEN];
533 rprintf(FINFO, "generator starting pid=%ld count=%d\n",
534 (long)getpid(), flist->count);
540 ? "delta-transmission disabled for local transfer or --whole-file\n"
541 : "delta transmission enabled\n");
544 /* we expect to just sit around now, so don't exit on a
545 timeout. If we really get a timeout then the other process should
549 for (i = 0; i < flist->count; i++) {
550 struct file_struct *file = flist->files[i];
551 struct file_struct copy;
555 /* we need to ensure that any directories we create have writeable
556 permissions initially so that we can create the files within
557 them. This is then fixed after the files are transferred */
558 if (!am_root && S_ISDIR(file->mode) && !(file->mode & S_IWUSR)) {
560 /* XXX: Could this be causing a problem on SCO? Perhaps their
561 * handling of permissions is strange? */
562 copy.mode |= S_IWUSR; /* user write */
566 recv_generator(local_name ? local_name : f_name_to(file, fbuf),
571 csum_length = SUM_LENGTH;
575 rprintf(FINFO,"generate_files phase=%d\n",phase);
577 write_int(f_out, -1);
579 /* files can cycle through the system more than once
580 * to catch initial checksum errors */
581 while ((i = get_redo_num()) != -1) {
582 struct file_struct *file = flist->files[i];
583 recv_generator(local_name ? local_name : f_name_to(file, fbuf),
589 rprintf(FINFO,"generate_files phase=%d\n",phase);
591 write_int(f_out, -1);
593 if (preserve_hard_links)
596 /* now we need to fix any directory permissions that were
597 * modified during the transfer */
598 for (i = 0; i < flist->count; i++) {
599 struct file_struct *file = flist->files[i];
600 if (!file->basename || !S_ISDIR(file->mode))
602 recv_generator(local_name ? local_name : f_name(file),
607 rprintf(FINFO,"generate_files finished\n");