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) 2004-2008 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.
29 extern int inc_recurse;
32 extern int preserve_acls;
33 extern int preserve_xattrs;
34 extern int make_backups;
35 extern int protocol_version;
36 extern int remove_source_files;
37 extern int stdout_format_has_i;
38 extern int maybe_ATTRS_REPORT;
39 extern int unsort_ndx;
40 extern char *basis_dir[MAX_BASIS_DIRS+1];
41 extern struct file_list *cur_flist;
43 #ifdef SUPPORT_HARD_LINKS
45 /* Starting with protocol 30, we use a simple hashtable on the sending side
46 * for hashing the st_dev and st_ino info. The receiving side gets told
47 * (via flags and a "group index") which items are hard-linked together, so
48 * we can avoid the pool of dev+inode data. For incremental recursion mode,
49 * the receiver will use a ndx hash to remember old pathnames. */
51 static struct hashtable *dev_tbl;
53 static struct hashtable *prior_hlinks;
55 static struct file_list *hlink_flist;
57 void init_hard_links(void)
59 if (am_sender || protocol_version < 30)
60 dev_tbl = hashtable_create(16, SIZEOF_INT64 == 8);
62 prior_hlinks = hashtable_create(1024, 0);
65 struct ht_int64_node *idev_find(int64 dev, int64 ino)
67 static struct ht_int64_node *dev_node = NULL;
68 struct hashtable *tbl;
70 if (!dev_node || dev_node->key != dev) {
71 /* We keep a separate hash table of inodes for every device. */
72 dev_node = hashtable_find(dev_tbl, dev, 1);
73 if (!(tbl = dev_node->data)) {
74 tbl = dev_node->data = hashtable_create(512, SIZEOF_INT64 == 8);
75 if (DEBUG_GTE(HLINK, 3)) {
77 "[%s] created hashtable for dev %s\n",
78 who_am_i(), big_num(dev));
84 return hashtable_find(tbl, ino, 1);
87 void idev_destroy(void)
91 for (i = 0; i < dev_tbl->size; i++) {
92 struct ht_int32_node *node = HT_NODE(dev_tbl, dev_tbl->nodes, i);
94 hashtable_destroy(node->data);
97 hashtable_destroy(dev_tbl);
100 static int hlink_compare_gnum(int *int1, int *int2)
102 struct file_struct *f1 = hlink_flist->sorted[*int1];
103 struct file_struct *f2 = hlink_flist->sorted[*int2];
104 int32 gnum1 = F_HL_GNUM(f1);
105 int32 gnum2 = F_HL_GNUM(f2);
108 return gnum1 > gnum2 ? 1 : -1;
110 return *int1 > *int2 ? 1 : -1;
113 static void match_gnums(int32 *ndx_list, int ndx_count)
116 struct file_struct *file, *file_next;
117 struct ht_int32_node *node = NULL;
118 int32 gnum, gnum_next;
120 qsort(ndx_list, ndx_count, sizeof ndx_list[0],
121 (int (*)()) hlink_compare_gnum);
123 for (from = 0; from < ndx_count; from++) {
124 file = hlink_flist->sorted[ndx_list[from]];
125 gnum = F_HL_GNUM(file);
127 node = hashtable_find(prior_hlinks, gnum, 1);
129 if (!(node->data = new_array0(char, 5)))
130 out_of_memory("match_gnums");
131 assert(gnum >= hlink_flist->ndx_start);
132 file->flags |= FLAG_HLINK_FIRST;
134 } else if (CVAL(node->data, 0) == 0) {
135 struct file_list *flist;
136 prev = IVAL(node->data, 1);
137 flist = flist_for_ndx(prev, NULL);
139 flist->files[prev - flist->ndx_start]->flags &= ~FLAG_HLINK_LAST;
141 /* We skipped all prior files in this
142 * group, so mark this as a "first". */
143 file->flags |= FLAG_HLINK_FIRST;
149 file->flags |= FLAG_HLINK_FIRST;
152 for ( ; from < ndx_count-1; file = file_next, gnum = gnum_next, from++) { /*SHARED ITERATOR*/
153 file_next = hlink_flist->sorted[ndx_list[from+1]];
154 gnum_next = F_HL_GNUM(file_next);
155 if (gnum != gnum_next)
157 F_HL_PREV(file) = prev;
158 /* The linked list uses over-the-wire ndx values. */
162 prev = ndx_list[from] + hlink_flist->ndx_start;
164 if (prev < 0 && !inc_recurse) {
165 /* Disable hard-link bit and set DONE so that
166 * HLINK_BUMP()-dependent values are unaffected. */
167 file->flags &= ~(FLAG_HLINKED | FLAG_HLINK_FIRST);
168 file->flags |= FLAG_HLINK_DONE;
172 file->flags |= FLAG_HLINK_LAST;
173 F_HL_PREV(file) = prev;
174 if (inc_recurse && CVAL(node->data, 0) == 0) {
178 prev = ndx_list[from] + hlink_flist->ndx_start;
179 SIVAL(node->data, 1, prev);
184 /* Analyze the hard-links in the file-list by creating a list of all the
185 * items that have hlink data, sorting them, and matching up identical
186 * values into clusters. These will be a single linked list from last
187 * to first when we're done. */
188 void match_hard_links(struct file_list *flist)
190 if (!list_only && flist->used) {
191 int i, ndx_count = 0;
194 if (!(ndx_list = new_array(int32, flist->used)))
195 out_of_memory("match_hard_links");
197 for (i = 0; i < flist->used; i++) {
198 if (F_IS_HLINKED(flist->sorted[i]))
199 ndx_list[ndx_count++] = i;
205 match_gnums(ndx_list, ndx_count);
209 if (protocol_version < 30)
213 static int maybe_hard_link(struct file_struct *file, int ndx,
214 const char *fname, int statret, stat_x *sxp,
215 const char *oldname, STRUCT_STAT *old_stp,
216 const char *realname, int itemizing, enum logcode code)
219 if (sxp->st.st_dev == old_stp->st_dev
220 && sxp->st.st_ino == old_stp->st_ino) {
222 itemize(fname, file, ndx, statret, sxp,
223 ITEM_LOCAL_CHANGE | ITEM_XNAME_FOLLOWS,
226 if (INFO_GTE(NAME, 2) && maybe_ATTRS_REPORT)
227 rprintf(FCLIENT, "%s is uptodate\n", fname);
228 file->flags |= FLAG_HLINK_DONE;
231 if (make_backups > 0) {
232 if (!make_backup(fname))
234 } else if (robust_unlink(fname)) {
235 rsyserr(FERROR_XFER, errno, "unlink %s failed",
241 if (hard_link_one(file, fname, oldname, 0)) {
243 itemize(fname, file, ndx, statret, sxp,
244 ITEM_LOCAL_CHANGE | ITEM_XNAME_FOLLOWS, 0,
247 if (code != FNONE && INFO_GTE(NAME, 1))
248 rprintf(code, "%s => %s\n", fname, realname);
254 /* Figure out if a prior entry is still there or if we just have a
255 * cached name for it. */
256 static char *check_prior(struct file_struct *file, int gnum,
257 int *prev_ndx_p, struct file_list **flist_p)
259 struct file_struct *fp;
260 struct ht_int32_node *node;
261 int prev_ndx = F_HL_PREV(file);
264 struct file_list *flist;
266 || (flist = flist_for_ndx(prev_ndx, NULL)) == NULL)
268 fp = flist->files[prev_ndx - flist->ndx_start];
269 if (!(fp->flags & FLAG_SKIP_HLINK)) {
270 *prev_ndx_p = prev_ndx;
274 F_HL_PREV(file) = prev_ndx = F_HL_PREV(fp);
278 && (node = hashtable_find(prior_hlinks, gnum, 0)) != NULL) {
279 assert(node->data != NULL);
280 if (CVAL(node->data, 0) != 0) {
285 /* The prior file must have been skipped. */
286 F_HL_PREV(file) = -1;
294 /* Only called if FLAG_HLINKED is set and FLAG_HLINK_FIRST is not. Returns:
295 * 0 = process the file, 1 = skip the file, -1 = error occurred. */
296 int hard_link_check(struct file_struct *file, int ndx, const char *fname,
297 int statret, stat_x *sxp, int itemizing,
301 char namebuf[MAXPATHLEN], altbuf[MAXPATHLEN];
302 char *realname, *prev_name;
303 struct file_list *flist;
304 int gnum = inc_recurse ? F_HL_GNUM(file) : -1;
307 prev_name = realname = check_prior(file, gnum, &prev_ndx, &flist);
310 struct file_struct *prev_file;
313 /* The previous file was skipped, so this one is
314 * treated as if it were the first in its group. */
315 if (DEBUG_GTE(HLINK, 2)) {
316 rprintf(FINFO, "hlink for %d (%s,%d): virtual first\n",
317 ndx, f_name(file, NULL), gnum);
322 prev_file = flist->files[prev_ndx - flist->ndx_start];
324 /* Is the previous link not complete yet? */
325 if (!(prev_file->flags & FLAG_HLINK_DONE)) {
326 /* Is the previous link being transferred? */
327 if (prev_file->flags & FLAG_FILE_SENT) {
328 /* Add ourselves to the list of files that will
329 * be updated when the transfer completes, and
330 * mark ourself as waiting for the transfer. */
331 F_HL_PREV(file) = F_HL_PREV(prev_file);
332 F_HL_PREV(prev_file) = ndx;
333 file->flags |= FLAG_FILE_SENT;
334 cur_flist->in_progress++;
335 if (DEBUG_GTE(HLINK, 2)) {
336 rprintf(FINFO, "hlink for %d (%s,%d): waiting for %d\n",
337 ndx, f_name(file, NULL), gnum, F_HL_PREV(file));
341 if (DEBUG_GTE(HLINK, 2)) {
342 rprintf(FINFO, "hlink for %d (%s,%d): looking for a leader\n",
343 ndx, f_name(file, NULL), gnum);
348 /* There is a finished file to link with! */
349 if (!(prev_file->flags & FLAG_HLINK_FIRST)) {
350 /* The previous previous is FIRST when prev is not. */
351 prev_name = realname = check_prior(prev_file, gnum, &prev_ndx, &flist);
352 /* Update our previous pointer to point to the FIRST. */
353 F_HL_PREV(file) = prev_ndx;
359 assert(flist != NULL);
360 prev_file = flist->files[prev_ndx - flist->ndx_start];
361 /* F_HL_PREV() is alt_dest value when DONE && FIRST. */
362 alt_dest = F_HL_PREV(prev_file);
363 if (DEBUG_GTE(HLINK, 2)) {
364 rprintf(FINFO, "hlink for %d (%s,%d): found flist match (alt %d)\n",
365 ndx, f_name(file, NULL), gnum, alt_dest);
368 if (alt_dest >= 0 && dry_run) {
369 pathjoin(namebuf, MAXPATHLEN, basis_dir[alt_dest],
370 f_name(prev_file, NULL));
372 realname = f_name(prev_file, altbuf);
374 prev_name = f_name(prev_file, namebuf);
375 realname = prev_name;
380 if (DEBUG_GTE(HLINK, 2)) {
381 rprintf(FINFO, "hlink for %d (%s,%d): leader is %d (%s)\n",
382 ndx, f_name(file, NULL), gnum, prev_ndx, prev_name);
385 if (link_stat(prev_name, &prev_st, 0) < 0) {
386 rsyserr(FERROR_XFER, errno, "stat %s failed",
387 full_fname(prev_name));
391 if (statret < 0 && basis_dir[0] != NULL) {
392 /* If we match an alt-dest item, we don't output this as a change. */
393 char cmpbuf[MAXPATHLEN];
397 alt_sx.acc_acl = alt_sx.def_acl = NULL;
399 #ifdef SUPPORT_XATTRS
403 pathjoin(cmpbuf, MAXPATHLEN, basis_dir[j], fname);
404 if (link_stat(cmpbuf, &alt_sx.st, 0) < 0)
407 if (prev_st.st_dev != alt_sx.st.st_dev
408 || prev_st.st_ino != alt_sx.st.st_ino)
411 if (stdout_format_has_i == 0
412 || (!INFO_GTE(NAME, 2) && stdout_format_has_i < 2)) {
415 if (INFO_GTE(NAME, 2) && maybe_ATTRS_REPORT)
416 rprintf(FCLIENT, "%s is uptodate\n", fname);
420 if (!unchanged_file(cmpbuf, file, &alt_sx.st))
423 if (unchanged_attrs(cmpbuf, file, &alt_sx))
425 } while (basis_dir[++j] != NULL);
429 if (preserve_acls && !S_ISLNK(file->mode)) {
431 if (!ACL_READY(alt_sx))
432 get_acl(cmpbuf, sxp);
434 sxp->acc_acl = alt_sx.acc_acl;
435 sxp->def_acl = alt_sx.def_acl;
436 alt_sx.acc_acl = alt_sx.def_acl = NULL;
440 #ifdef SUPPORT_XATTRS
441 if (preserve_xattrs) {
443 if (!XATTR_READY(alt_sx))
444 get_xattr(cmpbuf, sxp);
446 sxp->xattr = alt_sx.xattr;
456 #ifdef SUPPORT_XATTRS
463 if (maybe_hard_link(file, ndx, fname, statret, sxp, prev_name, &prev_st,
464 realname, itemizing, code) < 0)
467 if (remove_source_files == 1 && do_xfers)
468 send_msg_int(MSG_SUCCESS, ndx);
473 int hard_link_one(struct file_struct *file, const char *fname,
474 const char *oldname, int terse)
476 if (do_link(oldname, fname) < 0) {
479 if (!INFO_GTE(NAME, 1))
484 rsyserr(code, errno, "link %s => %s failed",
485 full_fname(fname), oldname);
489 file->flags |= FLAG_HLINK_DONE;
494 void finish_hard_link(struct file_struct *file, const char *fname, int fin_ndx,
495 STRUCT_STAT *stp, int itemizing, enum logcode code,
500 char prev_name[MAXPATHLEN], alt_name[MAXPATHLEN];
501 const char *our_name;
502 struct file_list *flist;
503 int prev_statret, ndx, prev_ndx = F_HL_PREV(file);
505 if (stp == NULL && prev_ndx >= 0) {
506 if (link_stat(fname, &st, 0) < 0) {
507 rsyserr(FERROR_XFER, errno, "stat %s failed",
514 /* FIRST combined with DONE means we were the first to get done. */
515 file->flags |= FLAG_HLINK_FIRST | FLAG_HLINK_DONE;
516 F_HL_PREV(file) = alt_dest;
517 if (alt_dest >= 0 && dry_run) {
518 pathjoin(alt_name, MAXPATHLEN, basis_dir[alt_dest],
525 prev_sx.acc_acl = prev_sx.def_acl = NULL;
527 #ifdef SUPPORT_XATTRS
528 prev_sx.xattr = NULL;
531 while ((ndx = prev_ndx) >= 0) {
533 flist = flist_for_ndx(ndx, "finish_hard_link");
534 file = flist->files[ndx - flist->ndx_start];
535 file->flags = (file->flags & ~FLAG_HLINK_FIRST) | FLAG_HLINK_DONE;
536 prev_ndx = F_HL_PREV(file);
537 F_HL_PREV(file) = fin_ndx;
538 prev_statret = link_stat(f_name(file, prev_name), &prev_sx.st, 0);
539 val = maybe_hard_link(file, ndx, prev_name, prev_statret, &prev_sx,
540 our_name, stp, fname, itemizing, code);
541 flist->in_progress--;
546 #ifdef SUPPORT_XATTRS
548 free_xattr(&prev_sx);
552 if (remove_source_files == 1 && do_xfers)
553 send_msg_int(MSG_SUCCESS, ndx);
557 int gnum = F_HL_GNUM(file);
558 struct ht_int32_node *node = hashtable_find(prior_hlinks, gnum, 0);
559 assert(node != NULL && node->data != NULL);
560 assert(CVAL(node->data, 0) == 0);
562 if (!(node->data = strdup(our_name)))
563 out_of_memory("finish_hard_link");
567 int skip_hard_link(struct file_struct *file, struct file_list **flist_p)
569 struct file_list *flist;
572 file->flags |= FLAG_SKIP_HLINK;
573 if (!(file->flags & FLAG_HLINK_LAST))
576 check_prior(file, F_HL_GNUM(file), &prev_ndx, &flist);
578 file = flist->files[prev_ndx - flist->ndx_start];
579 if (file->flags & (FLAG_HLINK_DONE|FLAG_FILE_SENT))
581 file->flags |= FLAG_HLINK_LAST;