2 * Routines to support hard-linking.
4 * Copyright (C) 1996 Andrew Tridgell
5 * Copyright (C) 1996 Paul Mackerras
6 * Copyright (C) 2002 Martin Pool <mbp@samba.org>
7 * Copyright (C) 2004-2009 Wayne Davison
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 3 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 along
20 * with this program; if not, visit the http://fsf.org website.
30 extern int inc_recurse;
33 extern int preserve_acls;
34 extern int preserve_xattrs;
35 extern int make_backups;
36 extern int protocol_version;
37 extern int remove_source_files;
38 extern int stdout_format_has_i;
39 extern int maybe_ATTRS_REPORT;
40 extern int unsort_ndx;
41 extern char *basis_dir[MAX_BASIS_DIRS+1];
42 extern struct file_list *cur_flist;
44 #ifdef SUPPORT_HARD_LINKS
46 /* Starting with protocol 30, we use a simple hashtable on the sending side
47 * for hashing the st_dev and st_ino info. The receiving side gets told
48 * (via flags and a "group index") which items are hard-linked together, so
49 * we can avoid the pool of dev+inode data. For incremental recursion mode,
50 * the receiver will use a ndx hash to remember old pathnames. */
52 static struct hashtable *dev_tbl;
54 static struct hashtable *prior_hlinks;
56 static struct file_list *hlink_flist;
58 void init_hard_links(void)
60 if (am_sender || protocol_version < 30)
61 dev_tbl = hashtable_create(16, SIZEOF_INT64 == 8);
63 prior_hlinks = hashtable_create(1024, 0);
66 struct ht_int64_node *idev_find(int64 dev, int64 ino)
68 static struct ht_int64_node *dev_node = NULL;
69 struct hashtable *tbl;
71 if (!dev_node || dev_node->key != dev) {
72 /* We keep a separate hash table of inodes for every device. */
73 dev_node = hashtable_find(dev_tbl, dev, 1);
74 if (!(tbl = dev_node->data)) {
75 tbl = dev_node->data = hashtable_create(512, SIZEOF_INT64 == 8);
76 if (DEBUG_GTE(HLINK, 3)) {
78 "[%s] created hashtable for dev %s\n",
79 who_am_i(), big_num(dev));
85 return hashtable_find(tbl, ino, 1);
88 void idev_destroy(void)
92 for (i = 0; i < dev_tbl->size; i++) {
93 struct ht_int32_node *node = HT_NODE(dev_tbl, dev_tbl->nodes, i);
95 hashtable_destroy(node->data);
98 hashtable_destroy(dev_tbl);
101 static int hlink_compare_gnum(int *int1, int *int2)
103 struct file_struct *f1 = hlink_flist->sorted[*int1];
104 struct file_struct *f2 = hlink_flist->sorted[*int2];
105 int32 gnum1 = F_HL_GNUM(f1);
106 int32 gnum2 = F_HL_GNUM(f2);
109 return gnum1 > gnum2 ? 1 : -1;
111 return *int1 > *int2 ? 1 : -1;
114 static void match_gnums(int32 *ndx_list, int ndx_count)
117 struct file_struct *file, *file_next;
118 struct ht_int32_node *node = NULL;
119 int32 gnum, gnum_next;
121 qsort(ndx_list, ndx_count, sizeof ndx_list[0],
122 (int (*)()) hlink_compare_gnum);
124 for (from = 0; from < ndx_count; from++) {
125 file = hlink_flist->sorted[ndx_list[from]];
126 gnum = F_HL_GNUM(file);
128 node = hashtable_find(prior_hlinks, gnum, 1);
130 if (!(node->data = new_array0(char, 5)))
131 out_of_memory("match_gnums");
132 assert(gnum >= hlink_flist->ndx_start);
133 file->flags |= FLAG_HLINK_FIRST;
135 } else if (CVAL(node->data, 0) == 0) {
136 struct file_list *flist;
137 prev = IVAL(node->data, 1);
138 flist = flist_for_ndx(prev, NULL);
140 flist->files[prev - flist->ndx_start]->flags &= ~FLAG_HLINK_LAST;
142 /* We skipped all prior files in this
143 * group, so mark this as a "first". */
144 file->flags |= FLAG_HLINK_FIRST;
150 file->flags |= FLAG_HLINK_FIRST;
153 for ( ; from < ndx_count-1; file = file_next, gnum = gnum_next, from++) { /*SHARED ITERATOR*/
154 file_next = hlink_flist->sorted[ndx_list[from+1]];
155 gnum_next = F_HL_GNUM(file_next);
156 if (gnum != gnum_next)
158 F_HL_PREV(file) = prev;
159 /* The linked list uses over-the-wire ndx values. */
163 prev = ndx_list[from] + hlink_flist->ndx_start;
165 if (prev < 0 && !inc_recurse) {
166 /* Disable hard-link bit and set DONE so that
167 * HLINK_BUMP()-dependent values are unaffected. */
168 file->flags &= ~(FLAG_HLINKED | FLAG_HLINK_FIRST);
169 file->flags |= FLAG_HLINK_DONE;
173 file->flags |= FLAG_HLINK_LAST;
174 F_HL_PREV(file) = prev;
175 if (inc_recurse && CVAL(node->data, 0) == 0) {
179 prev = ndx_list[from] + hlink_flist->ndx_start;
180 SIVAL(node->data, 1, prev);
185 /* Analyze the hard-links in the file-list by creating a list of all the
186 * items that have hlink data, sorting them, and matching up identical
187 * values into clusters. These will be a single linked list from last
188 * to first when we're done. */
189 void match_hard_links(struct file_list *flist)
191 if (!list_only && flist->used) {
192 int i, ndx_count = 0;
195 if (!(ndx_list = new_array(int32, flist->used)))
196 out_of_memory("match_hard_links");
198 for (i = 0; i < flist->used; i++) {
199 if (F_IS_HLINKED(flist->sorted[i]))
200 ndx_list[ndx_count++] = i;
206 match_gnums(ndx_list, ndx_count);
210 if (protocol_version < 30)
214 static int maybe_hard_link(struct file_struct *file, int ndx,
215 const char *fname, int statret, stat_x *sxp,
216 const char *oldname, STRUCT_STAT *old_stp,
217 const char *realname, int itemizing, enum logcode code)
221 if (sxp->st.st_dev == old_stp->st_dev
222 && sxp->st.st_ino == old_stp->st_ino) {
224 itemize(fname, file, ndx, statret, sxp,
225 ITEM_LOCAL_CHANGE | ITEM_XNAME_FOLLOWS,
228 if (INFO_GTE(NAME, 2) && maybe_ATTRS_REPORT)
229 rprintf(FCLIENT, "%s is uptodate\n", fname);
230 file->flags |= FLAG_HLINK_DONE;
233 if (make_backups > 0 && (ok = make_backup(fname, True)) == 0)
235 if (ok != 1 && robust_unlink(fname) && errno != ENOENT) {
236 rsyserr(FERROR_XFER, errno, "unlink %s failed",
242 if (hard_link_one(file, fname, oldname, 0)) {
244 itemize(fname, file, ndx, statret, sxp,
245 ITEM_LOCAL_CHANGE | ITEM_XNAME_FOLLOWS, 0,
248 if (code != FNONE && INFO_GTE(NAME, 1))
249 rprintf(code, "%s => %s\n", fname, realname);
255 /* Figure out if a prior entry is still there or if we just have a
256 * cached name for it. */
257 static char *check_prior(struct file_struct *file, int gnum,
258 int *prev_ndx_p, struct file_list **flist_p)
260 struct file_struct *fp;
261 struct ht_int32_node *node;
262 int prev_ndx = F_HL_PREV(file);
265 struct file_list *flist;
267 || (flist = flist_for_ndx(prev_ndx, NULL)) == NULL)
269 fp = flist->files[prev_ndx - flist->ndx_start];
270 if (!(fp->flags & FLAG_SKIP_HLINK)) {
271 *prev_ndx_p = prev_ndx;
275 F_HL_PREV(file) = prev_ndx = F_HL_PREV(fp);
279 && (node = hashtable_find(prior_hlinks, gnum, 0)) != NULL) {
280 assert(node->data != NULL);
281 if (CVAL(node->data, 0) != 0) {
286 /* The prior file must have been skipped. */
287 F_HL_PREV(file) = -1;
295 /* Only called if FLAG_HLINKED is set and FLAG_HLINK_FIRST is not. Returns:
296 * 0 = process the file, 1 = skip the file, -1 = error occurred. */
297 int hard_link_check(struct file_struct *file, int ndx, const char *fname,
298 int statret, stat_x *sxp, int itemizing,
302 char namebuf[MAXPATHLEN], altbuf[MAXPATHLEN];
303 char *realname, *prev_name;
304 struct file_list *flist;
305 int gnum = inc_recurse ? F_HL_GNUM(file) : -1;
308 prev_name = realname = check_prior(file, gnum, &prev_ndx, &flist);
311 struct file_struct *prev_file;
314 /* The previous file was skipped, so this one is
315 * treated as if it were the first in its group. */
316 if (DEBUG_GTE(HLINK, 2)) {
317 rprintf(FINFO, "hlink for %d (%s,%d): virtual first\n",
318 ndx, f_name(file, NULL), gnum);
323 prev_file = flist->files[prev_ndx - flist->ndx_start];
325 /* Is the previous link not complete yet? */
326 if (!(prev_file->flags & FLAG_HLINK_DONE)) {
327 /* Is the previous link being transferred? */
328 if (prev_file->flags & FLAG_FILE_SENT) {
329 /* Add ourselves to the list of files that will
330 * be updated when the transfer completes, and
331 * mark ourself as waiting for the transfer. */
332 F_HL_PREV(file) = F_HL_PREV(prev_file);
333 F_HL_PREV(prev_file) = ndx;
334 file->flags |= FLAG_FILE_SENT;
335 cur_flist->in_progress++;
336 if (DEBUG_GTE(HLINK, 2)) {
337 rprintf(FINFO, "hlink for %d (%s,%d): waiting for %d\n",
338 ndx, f_name(file, NULL), gnum, F_HL_PREV(file));
342 if (DEBUG_GTE(HLINK, 2)) {
343 rprintf(FINFO, "hlink for %d (%s,%d): looking for a leader\n",
344 ndx, f_name(file, NULL), gnum);
349 /* There is a finished file to link with! */
350 if (!(prev_file->flags & FLAG_HLINK_FIRST)) {
351 /* The previous previous is FIRST when prev is not. */
352 prev_name = realname = check_prior(prev_file, gnum, &prev_ndx, &flist);
353 /* Update our previous pointer to point to the FIRST. */
354 F_HL_PREV(file) = prev_ndx;
360 assert(flist != NULL);
361 prev_file = flist->files[prev_ndx - flist->ndx_start];
362 /* F_HL_PREV() is alt_dest value when DONE && FIRST. */
363 alt_dest = F_HL_PREV(prev_file);
364 if (DEBUG_GTE(HLINK, 2)) {
365 rprintf(FINFO, "hlink for %d (%s,%d): found flist match (alt %d)\n",
366 ndx, f_name(file, NULL), gnum, alt_dest);
369 if (alt_dest >= 0 && dry_run) {
370 pathjoin(namebuf, MAXPATHLEN, basis_dir[alt_dest],
371 f_name(prev_file, NULL));
373 realname = f_name(prev_file, altbuf);
375 prev_name = f_name(prev_file, namebuf);
376 realname = prev_name;
381 if (DEBUG_GTE(HLINK, 2)) {
382 rprintf(FINFO, "hlink for %d (%s,%d): leader is %d (%s)\n",
383 ndx, f_name(file, NULL), gnum, prev_ndx, prev_name);
386 if (link_stat(prev_name, &prev_st, 0) < 0) {
387 rsyserr(FERROR_XFER, errno, "stat %s failed",
388 full_fname(prev_name));
392 if (statret < 0 && basis_dir[0] != NULL) {
393 /* If we match an alt-dest item, we don't output this as a change. */
394 char cmpbuf[MAXPATHLEN];
397 init_stat_x(&alt_sx);
399 pathjoin(cmpbuf, MAXPATHLEN, basis_dir[j], fname);
400 if (link_stat(cmpbuf, &alt_sx.st, 0) < 0)
403 if (prev_st.st_dev != alt_sx.st.st_dev
404 || prev_st.st_ino != alt_sx.st.st_ino)
407 if (stdout_format_has_i == 0
408 || (!INFO_GTE(NAME, 2) && stdout_format_has_i < 2)) {
411 if (INFO_GTE(NAME, 2) && maybe_ATTRS_REPORT)
412 rprintf(FCLIENT, "%s is uptodate\n", fname);
416 if (!unchanged_file(cmpbuf, file, &alt_sx.st))
419 if (unchanged_attrs(cmpbuf, file, &alt_sx))
421 } while (basis_dir[++j] != NULL);
425 if (preserve_acls && !S_ISLNK(file->mode)) {
427 if (!ACL_READY(alt_sx))
428 get_acl(cmpbuf, sxp);
430 sxp->acc_acl = alt_sx.acc_acl;
431 sxp->def_acl = alt_sx.def_acl;
432 alt_sx.acc_acl = alt_sx.def_acl = NULL;
436 #ifdef SUPPORT_XATTRS
437 if (preserve_xattrs) {
439 if (!XATTR_READY(alt_sx))
440 get_xattr(cmpbuf, sxp);
442 sxp->xattr = alt_sx.xattr;
452 #ifdef SUPPORT_XATTRS
459 if (maybe_hard_link(file, ndx, fname, statret, sxp, prev_name, &prev_st,
460 realname, itemizing, code) < 0)
463 if (remove_source_files == 1 && do_xfers)
464 send_msg_int(MSG_SUCCESS, ndx);
469 int hard_link_one(struct file_struct *file, const char *fname,
470 const char *oldname, int terse)
472 if (do_link(oldname, fname) < 0) {
475 if (!INFO_GTE(NAME, 1))
480 rsyserr(code, errno, "link %s => %s failed",
481 full_fname(fname), oldname);
485 file->flags |= FLAG_HLINK_DONE;
490 void finish_hard_link(struct file_struct *file, const char *fname, int fin_ndx,
491 STRUCT_STAT *stp, int itemizing, enum logcode code,
496 char prev_name[MAXPATHLEN], alt_name[MAXPATHLEN];
497 const char *our_name;
498 struct file_list *flist;
499 int prev_statret, ndx, prev_ndx = F_HL_PREV(file);
501 if (stp == NULL && prev_ndx >= 0) {
502 if (link_stat(fname, &st, 0) < 0) {
503 rsyserr(FERROR_XFER, errno, "stat %s failed",
510 /* FIRST combined with DONE means we were the first to get done. */
511 file->flags |= FLAG_HLINK_FIRST | FLAG_HLINK_DONE;
512 F_HL_PREV(file) = alt_dest;
513 if (alt_dest >= 0 && dry_run) {
514 pathjoin(alt_name, MAXPATHLEN, basis_dir[alt_dest],
520 init_stat_x(&prev_sx);
522 while ((ndx = prev_ndx) >= 0) {
524 flist = flist_for_ndx(ndx, "finish_hard_link");
525 file = flist->files[ndx - flist->ndx_start];
526 file->flags = (file->flags & ~FLAG_HLINK_FIRST) | FLAG_HLINK_DONE;
527 prev_ndx = F_HL_PREV(file);
528 F_HL_PREV(file) = fin_ndx;
529 prev_statret = link_stat(f_name(file, prev_name), &prev_sx.st, 0);
530 val = maybe_hard_link(file, ndx, prev_name, prev_statret, &prev_sx,
531 our_name, stp, fname, itemizing, code);
532 flist->in_progress--;
537 #ifdef SUPPORT_XATTRS
539 free_xattr(&prev_sx);
543 if (remove_source_files == 1 && do_xfers)
544 send_msg_int(MSG_SUCCESS, ndx);
548 int gnum = F_HL_GNUM(file);
549 struct ht_int32_node *node = hashtable_find(prior_hlinks, gnum, 0);
550 assert(node != NULL && node->data != NULL);
551 assert(CVAL(node->data, 0) == 0);
553 if (!(node->data = strdup(our_name)))
554 out_of_memory("finish_hard_link");
558 int skip_hard_link(struct file_struct *file, struct file_list **flist_p)
560 struct file_list *flist;
563 file->flags |= FLAG_SKIP_HLINK;
564 if (!(file->flags & FLAG_HLINK_LAST))
567 check_prior(file, F_HL_GNUM(file), &prev_ndx, &flist);
569 file = flist->files[prev_ndx - flist->ndx_start];
570 if (file->flags & (FLAG_HLINK_DONE|FLAG_FILE_SENT))
572 file->flags |= FLAG_HLINK_LAST;