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) 2004-2015 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 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, 1);
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 /* Note that some OSes have a dev == 0, so increment to avoid storing a 0. */
71 if (!dev_node || dev_node->key != dev+1) {
72 /* We keep a separate hash table of inodes for every device. */
73 dev_node = hashtable_find(dev_tbl, dev+1, 1);
74 if (!(tbl = dev_node->data)) {
75 tbl = dev_node->data = hashtable_create(512, 1);
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 char *fname, int statret, stat_x *sxp,
216 const char *oldname, STRUCT_STAT *old_stp,
217 const char *realname, int itemizing, enum logcode code)
220 if (sxp->st.st_dev == old_stp->st_dev
221 && sxp->st.st_ino == old_stp->st_ino) {
223 itemize(fname, file, ndx, statret, sxp,
224 ITEM_LOCAL_CHANGE | ITEM_XNAME_FOLLOWS,
227 if (INFO_GTE(NAME, 2) && maybe_ATTRS_REPORT)
228 rprintf(FCLIENT, "%s is uptodate\n", fname);
229 file->flags |= FLAG_HLINK_DONE;
234 if (atomic_create(file, fname, NULL, oldname, MAKEDEV(0, 0), sxp, statret == 0 ? DEL_FOR_FILE : 0)) {
236 itemize(fname, file, ndx, statret, sxp,
237 ITEM_LOCAL_CHANGE | ITEM_XNAME_FOLLOWS, 0,
240 if (code != FNONE && INFO_GTE(NAME, 1))
241 rprintf(code, "%s => %s\n", fname, realname);
248 /* Figure out if a prior entry is still there or if we just have a
249 * cached name for it. */
250 static char *check_prior(struct file_struct *file, int gnum,
251 int *prev_ndx_p, struct file_list **flist_p)
253 struct file_struct *fp;
254 struct ht_int32_node *node;
255 int prev_ndx = F_HL_PREV(file);
258 struct file_list *flist;
260 || (flist = flist_for_ndx(prev_ndx, NULL)) == NULL)
262 fp = flist->files[prev_ndx - flist->ndx_start];
263 if (!(fp->flags & FLAG_SKIP_HLINK)) {
264 *prev_ndx_p = prev_ndx;
268 F_HL_PREV(file) = prev_ndx = F_HL_PREV(fp);
272 && (node = hashtable_find(prior_hlinks, gnum, 0)) != NULL) {
273 assert(node->data != NULL);
274 if (CVAL(node->data, 0) != 0) {
279 /* The prior file must have been skipped. */
280 F_HL_PREV(file) = -1;
288 /* Only called if FLAG_HLINKED is set and FLAG_HLINK_FIRST is not. Returns:
289 * 0 = process the file, 1 = skip the file, -1 = error occurred. */
290 int hard_link_check(struct file_struct *file, int ndx, char *fname,
291 int statret, stat_x *sxp, int itemizing,
295 char namebuf[MAXPATHLEN], altbuf[MAXPATHLEN];
296 char *realname, *prev_name;
297 struct file_list *flist;
298 int gnum = inc_recurse ? F_HL_GNUM(file) : -1;
301 prev_name = realname = check_prior(file, gnum, &prev_ndx, &flist);
304 struct file_struct *prev_file;
307 /* The previous file was skipped, so this one is
308 * treated as if it were the first in its group. */
309 if (DEBUG_GTE(HLINK, 2)) {
310 rprintf(FINFO, "hlink for %d (%s,%d): virtual first\n",
311 ndx, f_name(file, NULL), gnum);
316 prev_file = flist->files[prev_ndx - flist->ndx_start];
318 /* Is the previous link not complete yet? */
319 if (!(prev_file->flags & FLAG_HLINK_DONE)) {
320 /* Is the previous link being transferred? */
321 if (prev_file->flags & FLAG_FILE_SENT) {
322 /* Add ourselves to the list of files that will
323 * be updated when the transfer completes, and
324 * mark ourself as waiting for the transfer. */
325 F_HL_PREV(file) = F_HL_PREV(prev_file);
326 F_HL_PREV(prev_file) = ndx;
327 file->flags |= FLAG_FILE_SENT;
328 cur_flist->in_progress++;
329 if (DEBUG_GTE(HLINK, 2)) {
330 rprintf(FINFO, "hlink for %d (%s,%d): waiting for %d\n",
331 ndx, f_name(file, NULL), gnum, F_HL_PREV(file));
335 if (DEBUG_GTE(HLINK, 2)) {
336 rprintf(FINFO, "hlink for %d (%s,%d): looking for a leader\n",
337 ndx, f_name(file, NULL), gnum);
342 /* There is a finished file to link with! */
343 if (!(prev_file->flags & FLAG_HLINK_FIRST)) {
344 /* The previous previous is FIRST when prev is not. */
345 prev_name = realname = check_prior(prev_file, gnum, &prev_ndx, &flist);
346 /* Update our previous pointer to point to the FIRST. */
347 F_HL_PREV(file) = prev_ndx;
353 assert(flist != NULL);
354 prev_file = flist->files[prev_ndx - flist->ndx_start];
355 /* F_HL_PREV() is alt_dest value when DONE && FIRST. */
356 alt_dest = F_HL_PREV(prev_file);
357 if (DEBUG_GTE(HLINK, 2)) {
358 rprintf(FINFO, "hlink for %d (%s,%d): found flist match (alt %d)\n",
359 ndx, f_name(file, NULL), gnum, alt_dest);
362 if (alt_dest >= 0 && dry_run) {
363 pathjoin(namebuf, MAXPATHLEN, basis_dir[alt_dest],
364 f_name(prev_file, NULL));
366 realname = f_name(prev_file, altbuf);
368 prev_name = f_name(prev_file, namebuf);
369 realname = prev_name;
374 if (DEBUG_GTE(HLINK, 2)) {
375 rprintf(FINFO, "hlink for %d (%s,%d): leader is %d (%s)\n",
376 ndx, f_name(file, NULL), gnum, prev_ndx, prev_name);
379 if (link_stat(prev_name, &prev_st, 0) < 0) {
380 if (!dry_run || errno != ENOENT) {
381 rsyserr(FERROR_XFER, errno, "stat %s failed", full_fname(prev_name));
384 /* A new hard-link will get a new dev & inode, so approximate
385 * those values in dry-run mode by zeroing them. */
386 memset(&prev_st, 0, sizeof prev_st);
389 if (statret < 0 && basis_dir[0] != NULL) {
390 /* If we match an alt-dest item, we don't output this as a change. */
391 char cmpbuf[MAXPATHLEN];
394 init_stat_x(&alt_sx);
396 pathjoin(cmpbuf, MAXPATHLEN, basis_dir[j], fname);
397 if (link_stat(cmpbuf, &alt_sx.st, 0) < 0)
400 if (prev_st.st_dev != alt_sx.st.st_dev
401 || prev_st.st_ino != alt_sx.st.st_ino)
404 if (stdout_format_has_i == 0
405 || (!INFO_GTE(NAME, 2) && stdout_format_has_i < 2)) {
408 if (INFO_GTE(NAME, 2) && maybe_ATTRS_REPORT)
409 rprintf(FCLIENT, "%s is uptodate\n", fname);
413 if (!unchanged_file(cmpbuf, file, &alt_sx.st))
416 if (unchanged_attrs(cmpbuf, file, &alt_sx))
418 } while (basis_dir[++j] != NULL);
422 if (preserve_acls && !S_ISLNK(file->mode)) {
424 if (!ACL_READY(alt_sx))
425 get_acl(cmpbuf, sxp);
427 sxp->acc_acl = alt_sx.acc_acl;
428 sxp->def_acl = alt_sx.def_acl;
429 alt_sx.acc_acl = alt_sx.def_acl = NULL;
433 #ifdef SUPPORT_XATTRS
434 if (preserve_xattrs) {
436 if (!XATTR_READY(alt_sx))
437 get_xattr(cmpbuf, sxp);
439 sxp->xattr = alt_sx.xattr;
445 free_stat_x(&alt_sx);
448 if (maybe_hard_link(file, ndx, fname, statret, sxp, prev_name, &prev_st,
449 realname, itemizing, code) < 0)
452 if (remove_source_files == 1 && do_xfers)
453 send_msg_int(MSG_SUCCESS, ndx);
458 int hard_link_one(struct file_struct *file, const char *fname,
459 const char *oldname, int terse)
461 if (do_link(oldname, fname) < 0) {
464 if (!INFO_GTE(NAME, 1))
469 rsyserr(code, errno, "link %s => %s failed",
470 full_fname(fname), oldname);
474 file->flags |= FLAG_HLINK_DONE;
479 void finish_hard_link(struct file_struct *file, const char *fname, int fin_ndx,
480 STRUCT_STAT *stp, int itemizing, enum logcode code,
485 char prev_name[MAXPATHLEN], alt_name[MAXPATHLEN];
486 const char *our_name;
487 struct file_list *flist;
488 int prev_statret, ndx, prev_ndx = F_HL_PREV(file);
490 if (stp == NULL && prev_ndx >= 0) {
491 if (link_stat(fname, &st, 0) < 0 && !dry_run) {
492 rsyserr(FERROR_XFER, errno, "stat %s failed",
499 /* FIRST combined with DONE means we were the first to get done. */
500 file->flags |= FLAG_HLINK_FIRST | FLAG_HLINK_DONE;
501 F_HL_PREV(file) = alt_dest;
502 if (alt_dest >= 0 && dry_run) {
503 pathjoin(alt_name, MAXPATHLEN, basis_dir[alt_dest],
509 init_stat_x(&prev_sx);
511 while ((ndx = prev_ndx) >= 0) {
513 flist = flist_for_ndx(ndx, "finish_hard_link");
514 file = flist->files[ndx - flist->ndx_start];
515 file->flags = (file->flags & ~FLAG_HLINK_FIRST) | FLAG_HLINK_DONE;
516 prev_ndx = F_HL_PREV(file);
517 F_HL_PREV(file) = fin_ndx;
518 prev_statret = link_stat(f_name(file, prev_name), &prev_sx.st, 0);
519 val = maybe_hard_link(file, ndx, prev_name, prev_statret, &prev_sx,
520 our_name, stp, fname, itemizing, code);
521 flist->in_progress--;
522 free_stat_x(&prev_sx);
525 if (remove_source_files == 1 && do_xfers)
526 send_msg_int(MSG_SUCCESS, ndx);
530 int gnum = F_HL_GNUM(file);
531 struct ht_int32_node *node = hashtable_find(prior_hlinks, gnum, 0);
533 rprintf(FERROR, "Unable to find a hlink node for %d (%s)\n", gnum, f_name(file, prev_name));
534 exit_cleanup(RERR_MESSAGEIO);
536 if (node->data == NULL) {
537 rprintf(FERROR, "Hlink node data for %d is NULL (%s)\n", gnum, f_name(file, prev_name));
538 exit_cleanup(RERR_MESSAGEIO);
540 if (CVAL(node->data, 0) != 0) {
541 rprintf(FERROR, "Hlink node data for %d already has path=%s (%s)\n",
542 gnum, (char*)node->data, f_name(file, prev_name));
543 exit_cleanup(RERR_MESSAGEIO);
546 if (!(node->data = strdup(our_name)))
547 out_of_memory("finish_hard_link");
551 int skip_hard_link(struct file_struct *file, struct file_list **flist_p)
553 struct file_list *flist;
556 file->flags |= FLAG_SKIP_HLINK;
557 if (!(file->flags & FLAG_HLINK_LAST))
560 check_prior(file, F_HL_GNUM(file), &prev_ndx, &flist);
562 file = flist->files[prev_ndx - flist->ndx_start];
563 if (file->flags & (FLAG_HLINK_DONE|FLAG_FILE_SENT))
565 file->flags |= FLAG_HLINK_LAST;