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);
296 (S_ISDIR(st.st_mode) == S_ISDIR(file->mode))) {
297 /* if the file exists already and we aren't perserving
298 * permissions then act as though the remote end sent
299 * us the file permissions we already have */
300 file->mode = (file->mode & ~CHMOD_BITS)
301 | (st.st_mode & CHMOD_BITS);
304 if (S_ISDIR(file->mode)) {
305 /* The file to be received is a directory, so we need
306 * to prepare appropriately. If there is already a
307 * file of that name and it is *not* a directory, then
308 * we need to delete it. If it doesn't exist, then
309 * recursively create it. */
312 return; /* TODO: causes inaccuracies -- fix */
313 if (statret == 0 && !S_ISDIR(st.st_mode)) {
314 if (robust_unlink(fname) != 0) {
315 rsyserr(FERROR, errno,
316 "recv_generator: unlink %s to make room for directory",
322 if (statret != 0 && do_mkdir(fname,file->mode) != 0 && errno != EEXIST) {
323 if (!(relative_paths && errno == ENOENT
324 && create_directory_path(fname, orig_umask) == 0
325 && do_mkdir(fname, file->mode) == 0)) {
326 rsyserr(FERROR, errno,
327 "recv_generator: mkdir %s failed",
331 /* f_out is set to -1 when doing final directory-permission
332 * and modification-time repair. */
333 if (set_perms(fname, file, statret ? NULL : &st, 0)
334 && verbose && f_out != -1)
335 rprintf(FINFO,"%s/\n",fname);
339 if (preserve_links && S_ISLNK(file->mode)) {
341 char lnk[MAXPATHLEN];
344 if (safe_symlinks && unsafe_symlink(file->u.link, fname)) {
346 rprintf(FINFO, "ignoring unsafe symlink %s -> \"%s\"\n",
347 full_fname(fname), file->u.link);
352 l = readlink(fname,lnk,MAXPATHLEN-1);
355 /* A link already pointing to the
356 * right place -- no further action
358 if (strcmp(lnk,file->u.link) == 0) {
359 set_perms(fname, file, &st,
364 /* Not a symlink, so delete whatever's
365 * already there and put a new symlink
369 if (do_symlink(file->u.link,fname) != 0) {
370 rsyserr(FERROR, errno, "symlink %s -> \"%s\" failed",
371 full_fname(fname), file->u.link);
373 set_perms(fname,file,NULL,0);
375 rprintf(FINFO,"%s -> %s\n", fname,file->u.link);
383 if (am_root && preserve_devices && IS_DEVICE(file->mode)) {
385 st.st_mode != file->mode ||
386 st.st_rdev != file->u.rdev) {
389 rprintf(FINFO,"mknod(%s,0%o,0x%x)\n",
390 fname,(int)file->mode,(int)file->u.rdev);
392 if (do_mknod(fname,file->mode,file->u.rdev) != 0) {
393 rsyserr(FERROR, errno, "mknod %s failed",
396 set_perms(fname,file,NULL,0);
398 rprintf(FINFO,"%s\n",fname);
401 set_perms(fname, file, &st, PERMS_REPORT);
407 if (preserve_hard_links && hard_link_check(file, HL_CHECK_MASTER))
410 if (!S_ISREG(file->mode)) {
411 rprintf(FINFO, "skipping non-regular file \"%s\"\n",fname);
417 if (statret == -1 && compare_dest != NULL) {
418 /* try the file at compare_dest instead */
419 int saveerrno = errno;
420 pathjoin(fnamecmpbuf, sizeof fnamecmpbuf, compare_dest, fname);
421 statret = link_stat(fnamecmpbuf, &st, 0);
422 if (!S_ISREG(st.st_mode))
427 else if (link_dest && !dry_run) {
428 if (do_link(fnamecmpbuf, fname) != 0) {
430 rsyserr(FINFO, errno, "link %s => %s",
434 fnamecmp = fnamecmpbuf;
438 fnamecmp = fnamecmpbuf;
442 if (preserve_hard_links && hard_link_check(file, HL_SKIP))
444 if (errno == ENOENT) {
446 if (!dry_run && !read_batch)
447 write_sum_head(f_out, NULL);
448 } else if (verbose > 1) {
449 rsyserr(FERROR, errno,
450 "recv_generator: failed to open %s",
456 if (!S_ISREG(st.st_mode)) {
457 if (delete_file(fname) != 0) {
461 /* now pretend the file didn't exist */
462 if (preserve_hard_links && hard_link_check(file, HL_SKIP))
465 if (!dry_run && !read_batch)
466 write_sum_head(f_out, NULL);
470 if (opt_ignore_existing && fnamecmp == fname) {
472 rprintf(FINFO,"%s exists\n",fname);
476 if (update_only && fnamecmp == fname
477 && cmp_modtime(st.st_mtime, file->modtime) > 0) {
479 rprintf(FINFO,"%s is newer\n",fname);
483 if (skip_file(fname, file, &st)) {
484 if (fnamecmp == fname)
485 set_perms(fname, file, &st, PERMS_REPORT);
489 if (dry_run || read_batch) {
494 if (whole_file > 0) {
496 write_sum_head(f_out, NULL);
501 fd = do_open(fnamecmp, O_RDONLY, 0);
504 rsyserr(FERROR, errno, "failed to open %s, continuing",
505 full_fname(fnamecmp));
506 /* pretend the file didn't exist */
507 if (preserve_hard_links && hard_link_check(file, HL_SKIP))
510 write_sum_head(f_out, NULL);
515 rprintf(FINFO,"gen mapped %s of size %.0f\n", fnamecmp,
520 rprintf(FINFO, "generating and sending sums for %d\n", i);
523 generate_and_send_sums(fd, st.st_size, f_out);
529 void generate_files(int f_out, struct file_list *flist, char *local_name)
533 char fbuf[MAXPATHLEN];
536 rprintf(FINFO, "generator starting pid=%ld count=%d\n",
537 (long)getpid(), flist->count);
543 ? "delta-transmission disabled for local transfer or --whole-file\n"
544 : "delta transmission enabled\n");
547 /* we expect to just sit around now, so don't exit on a
548 timeout. If we really get a timeout then the other process should
552 for (i = 0; i < flist->count; i++) {
553 struct file_struct *file = flist->files[i];
554 struct file_struct copy;
558 /* we need to ensure that any directories we create have writeable
559 permissions initially so that we can create the files within
560 them. This is then fixed after the files are transferred */
561 if (!am_root && S_ISDIR(file->mode) && !(file->mode & S_IWUSR)) {
563 /* XXX: Could this be causing a problem on SCO? Perhaps their
564 * handling of permissions is strange? */
565 copy.mode |= S_IWUSR; /* user write */
569 recv_generator(local_name ? local_name : f_name_to(file, fbuf),
574 csum_length = SUM_LENGTH;
578 rprintf(FINFO,"generate_files phase=%d\n",phase);
580 write_int(f_out, -1);
582 /* files can cycle through the system more than once
583 * to catch initial checksum errors */
584 while ((i = get_redo_num()) != -1) {
585 struct file_struct *file = flist->files[i];
586 recv_generator(local_name ? local_name : f_name_to(file, fbuf),
592 rprintf(FINFO,"generate_files phase=%d\n",phase);
594 write_int(f_out, -1);
596 if (preserve_hard_links)
599 /* now we need to fix any directory permissions that were
600 * modified during the transfer */
601 for (i = 0; i < flist->count; i++) {
602 struct file_struct *file = flist->files[i];
603 if (!file->basename || !S_ISDIR(file->mode))
605 recv_generator(local_name ? local_name : f_name(file),
610 rprintf(FINFO,"generate_files finished\n");