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 preserve_links;
31 extern int preserve_devices;
32 extern int preserve_hard_links;
33 extern int preserve_perms;
34 extern int preserve_uid;
35 extern int preserve_gid;
36 extern int update_only;
37 extern int opt_ignore_existing;
38 extern int csum_length;
39 extern int ignore_times;
41 extern int io_timeout;
42 extern int protocol_version;
43 extern int always_checksum;
44 extern char *compare_dest;
48 /* choose whether to skip a particular file */
49 static int skip_file(char *fname, struct file_struct *file, STRUCT_STAT *st)
51 if (st->st_size != file->length) {
56 && (st->st_mode & ~_S_IFMT) != (file->mode & ~_S_IFMT))
59 if (am_root && preserve_uid && st->st_uid != file->uid)
62 if (preserve_gid && file->gid != GID_NONE
63 && st->st_gid != file->gid)
67 /* if always checksum is set then we use the checksum instead
68 of the file time to determine whether to sync */
69 if (always_checksum && S_ISREG(st->st_mode)) {
70 char sum[MD4_SUM_LENGTH];
71 char fnamecmpdest[MAXPATHLEN];
73 if (compare_dest != NULL) {
74 if (access(fname, 0) != 0) {
75 pathjoin(fnamecmpdest, sizeof fnamecmpdest,
80 file_checksum(fname,sum,st->st_size);
81 return memcmp(sum, file->u.sum, protocol_version < 21 ? 2
82 : MD4_SUM_LENGTH) == 0;
93 return (cmp_modtime(st->st_mtime,file->modtime) == 0);
98 * NULL sum_struct means we have no checksums
100 void write_sum_head(int f, struct sum_struct *sum)
102 static struct sum_struct null_sum;
104 if (sum == (struct sum_struct *)NULL)
107 write_int(f, sum->count);
108 write_int(f, sum->blength);
109 if (protocol_version >= 27)
110 write_int(f, sum->s2length);
111 write_int(f, sum->remainder);
115 * set (initialize) the size entries in the per-file sum_struct
116 * calulating dynamic block ans checksum sizes.
118 * This is only called from generate_and_send_sums() but is a seperate
119 * function to encapsulate the logic.
121 * The block size is a rounded square root of file length.
123 * The checksum size is determined according to:
124 * blocksum_bits = BLOCKSUM_EXP + 2*log2(file_len) - log2(block_len)
125 * provided by Donovan Baarda which gives a probability of rsync
126 * algorithm corrupting data and falling back using the whole md4
129 * This might be made one of several selectable heuristics.
132 static void sum_sizes_sqroot(struct sum_struct *sum, uint64 len)
134 extern unsigned int block_size;
135 unsigned int blength;
141 blength = block_size;
142 } else if (len <= BLOCK_SIZE * BLOCK_SIZE) {
143 blength = BLOCK_SIZE;
153 if (len < (uint64)blength * blength)
156 } while (c >= 8); /* round to multiple of 8 */
157 blength = MAX(blength, BLOCK_SIZE);
160 if (protocol_version < 27) {
161 s2length = csum_length;
162 } else if (csum_length == SUM_LENGTH) {
163 s2length = SUM_LENGTH;
165 int b = BLOCKSUM_BIAS;
171 while (c >>= 1 && b) {
174 s2length = (b + 1 - 32 + 7) / 8; /* add a bit,
177 * --optimize in compiler--
179 s2length = MAX(s2length, csum_length);
180 s2length = MIN(s2length, SUM_LENGTH);
184 sum->blength = blength;
185 sum->s2length = s2length;
186 sum->count = (len + (blength - 1)) / blength;
187 sum->remainder = (len % blength);
189 if (sum->count && verbose > 2) {
190 rprintf(FINFO, "count=%.0f rem=%u blength=%u s2length=%d flength=%.0f\n",
191 (double)sum->count, sum->remainder, sum->blength,
192 sum->s2length, (double)sum->flength);
197 * Perhaps we want to just send an empty checksum set for this file,
198 * which will force the whole thing to be literally transferred.
200 * When do we do this? If the user's explicitly said they
201 * want the whole thing, or if { they haven't explicitly
202 * requested a delta, and it's local but not batch mode.}
205 static BOOL disable_deltas_p(void)
207 extern int whole_file;
208 extern int local_server;
209 extern int write_batch;
213 if (whole_file == 0 || write_batch)
220 * Generate and send a stream of signatures/checksums that describe a buffer
222 * Generate approximately one checksum every block_len bytes.
224 static void generate_and_send_sums(struct map_struct *buf, size_t len, int f_out)
227 struct sum_struct sum;
230 sum_sizes_sqroot(&sum, len);
232 write_sum_head(f_out, &sum);
234 for (i = 0; i < sum.count; i++) {
235 unsigned int n1 = MIN(len, sum.blength);
236 char *map = map_ptr(buf, offset, n1);
237 uint32 sum1 = get_checksum1(map, n1);
238 char sum2[SUM_LENGTH];
240 get_checksum2(map, n1, sum2);
244 "chunk[%.0f] offset=%.0f len=%u sum1=%08lx\n",
245 (double)i, (double)offset, n1,
246 (unsigned long)sum1);
248 write_int(f_out, sum1);
249 write_buf(f_out, sum2, sum.s2length);
258 * Acts on file number @p i from @p flist, whose name is @p fname.
260 * First fixes up permissions, then generates checksums for the file.
262 * @note This comment was added later by mbp who was trying to work it
263 * out. It might be wrong.
265 void recv_generator(char *fname, struct file_struct *file, int i, int f_out)
269 struct map_struct *mapbuf;
272 char fnamecmpbuf[MAXPATHLEN];
273 extern char *compare_dest;
274 extern int list_only;
275 extern int only_existing;
276 extern int orig_umask;
282 rprintf(FINFO,"recv_generator(%s,%d)\n",fname,i);
284 statret = link_stat(fname,&st);
286 if (only_existing && statret == -1 && errno == ENOENT) {
287 /* we only want to update existing files */
288 if (verbose > 1) rprintf(FINFO, "not creating new file \"%s\"\n",fname);
294 (S_ISDIR(st.st_mode) == S_ISDIR(file->mode))) {
295 /* if the file exists already and we aren't perserving
296 * permissions then act as though the remote end sent
297 * us the file permissions we already have */
298 file->mode = (file->mode & _S_IFMT) | (st.st_mode & ~_S_IFMT);
301 if (S_ISDIR(file->mode)) {
302 /* The file to be received is a directory, so we need
303 * to prepare appropriately. If there is already a
304 * file of that name and it is *not* a directory, then
305 * we need to delete it. If it doesn't exist, then
306 * recursively create it. */
308 if (dry_run) return; /* XXXX -- might cause inaccuracies?? -- mbp */
309 if (statret == 0 && !S_ISDIR(st.st_mode)) {
310 if (robust_unlink(fname) != 0) {
312 "recv_generator: unlink %s to make room for directory: %s\n",
313 full_fname(fname), strerror(errno));
318 if (statret != 0 && do_mkdir(fname,file->mode) != 0 && errno != EEXIST) {
319 if (!(relative_paths && errno==ENOENT &&
320 create_directory_path(fname, orig_umask)==0 &&
321 do_mkdir(fname,file->mode)==0)) {
322 rprintf(FERROR, "recv_generator: mkdir %s failed: %s\n",
323 full_fname(fname), strerror(errno));
326 /* f_out is set to -1 when doing final directory
327 permission and modification time repair */
328 if (set_perms(fname,file,NULL,0) && verbose && (f_out != -1))
329 rprintf(FINFO,"%s/\n",fname);
333 if (preserve_links && S_ISLNK(file->mode)) {
335 char lnk[MAXPATHLEN];
337 extern int safe_symlinks;
339 if (safe_symlinks && unsafe_symlink(file->u.link, fname)) {
341 rprintf(FINFO, "ignoring unsafe symlink %s -> \"%s\"\n",
342 full_fname(fname), file->u.link);
347 l = readlink(fname,lnk,MAXPATHLEN-1);
350 /* A link already pointing to the
351 * right place -- no further action
353 if (strcmp(lnk,file->u.link) == 0) {
354 set_perms(fname,file,&st,1);
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 rprintf(FERROR, "symlink %s -> \"%s\" failed: %s\n",
365 full_fname(fname), file->u.link, strerror(errno));
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 (DEV64_T)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);
385 if (do_mknod(fname,file->mode,file->u.rdev) != 0) {
386 rprintf(FERROR, "mknod %s failed: %s\n",
387 full_fname(fname), strerror(errno));
389 set_perms(fname,file,NULL,0);
391 rprintf(FINFO,"%s\n",fname);
394 set_perms(fname,file,&st,1);
400 if (preserve_hard_links && file->link_u.links && file->F_HEAD != file) {
402 rprintf(FINFO, "recv_generator: \"%s\" is a hard link\n",
408 if (!S_ISREG(file->mode)) {
409 rprintf(FINFO, "skipping non-regular file \"%s\"\n",fname);
415 if ((statret == -1) && (compare_dest != NULL)) {
416 /* try the file at compare_dest instead */
417 int saveerrno = errno;
418 pathjoin(fnamecmpbuf, sizeof fnamecmpbuf, compare_dest, fname);
419 statret = link_stat(fnamecmpbuf,&st);
420 if (!S_ISREG(st.st_mode))
425 else if (link_dest && !dry_run) {
426 if (do_link(fnamecmpbuf, fname) != 0) {
428 rprintf(FINFO,"link %s => %s : %s\n",
433 fnamecmp = fnamecmpbuf;
437 fnamecmp = fnamecmpbuf;
441 if (errno == ENOENT) {
443 if (!dry_run) write_sum_head(f_out, NULL);
444 } else if (verbose > 1) {
446 "recv_generator: failed to open %s: %s\n",
447 full_fname(fname), strerror(errno));
452 if (!S_ISREG(st.st_mode)) {
453 if (delete_file(fname) != 0) {
457 /* now pretend the file didn't exist */
459 if (!dry_run) write_sum_head(f_out, NULL);
463 if (opt_ignore_existing && fnamecmp == fname) {
465 rprintf(FINFO,"%s exists\n",fname);
469 if (update_only && cmp_modtime(st.st_mtime,file->modtime)>0 && fnamecmp == fname) {
471 rprintf(FINFO,"%s is newer\n",fname);
475 if (skip_file(fname, file, &st)) {
476 if (fnamecmp == fname)
477 set_perms(fname,file,&st,1);
486 if (disable_deltas_p()) {
488 write_sum_head(f_out, NULL);
493 fd = do_open(fnamecmp, O_RDONLY, 0);
496 rprintf(FERROR, "failed to open %s, continuing: %s\n",
497 full_fname(fnamecmp), strerror(errno));
498 /* pretend the file didn't exist */
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);
521 if (mapbuf) unmap_file(mapbuf);
525 void generate_files(int f, struct file_list *flist, char *local_name)
529 char fbuf[MAXPATHLEN];
532 rprintf(FINFO,"generator starting pid=%d count=%d\n",
533 (int)getpid(),flist->count);
538 ? "delta-transmission disabled for local transfer or --whole-file\n"
539 : "delta transmission enabled\n");
542 /* we expect to just sit around now, so don't exit on a
543 timeout. If we really get a timeout then the other process should
547 for (i = 0; i < flist->count; i++) {
548 struct file_struct *file = flist->files[i];
549 struct file_struct copy;
553 /* we need to ensure that any directories we create have writeable
554 permissions initially so that we can create the files within
555 them. This is then fixed after the files are transferred */
556 if (!am_root && S_ISDIR(file->mode) && !(file->mode & S_IWUSR)) {
558 /* XXX: Could this be causing a problem on SCO? Perhaps their
559 * handling of permissions is strange? */
560 copy.mode |= S_IWUSR; /* user write */
564 recv_generator(local_name ? local_name : f_name_to(file, fbuf),
569 csum_length = SUM_LENGTH;
573 rprintf(FINFO,"generate_files phase=%d\n",phase);
577 /* files can cycle through the system more than once
578 * to catch initial checksum errors */
579 while ((i = get_redo_num()) != -1) {
580 struct file_struct *file = flist->files[i];
581 recv_generator(local_name ? local_name : f_name_to(file, fbuf),
587 rprintf(FINFO,"generate_files phase=%d\n",phase);