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 make_backups;
34 extern int protocol_version;
35 extern int remove_source_files;
36 extern int stdout_format_has_i;
37 extern int maybe_ATTRS_REPORT;
38 extern int unsort_ndx;
39 extern char *basis_dir[MAX_BASIS_DIRS+1];
40 extern struct file_list *cur_flist;
42 #ifdef SUPPORT_HARD_LINKS
44 /* Starting with protocol 30, we use a simple hashtable on the sending side
45 * for hashing the st_dev and st_ino info. The receiving side gets told
46 * (via flags and a "group index") which items are hard-linked together, so
47 * we can avoid the pool of dev+inode data. For incremental recursion mode,
48 * the receiver will use a ndx hash to remember old pathnames. */
50 static struct hashtable *dev_tbl;
52 static struct hashtable *prior_hlinks;
54 static struct file_list *hlink_flist;
56 void init_hard_links(void)
58 if (am_sender || protocol_version < 30)
59 dev_tbl = hashtable_create(16, SIZEOF_INT64 == 8);
61 prior_hlinks = hashtable_create(1024, 0);
64 struct ht_int64_node *idev_find(int64 dev, int64 ino)
66 static struct ht_int64_node *dev_node = NULL;
67 struct hashtable *tbl;
69 if (!dev_node || dev_node->key != dev) {
70 /* We keep a separate hash table of inodes for every device. */
71 dev_node = hashtable_find(dev_tbl, dev, 1);
72 if (!(tbl = dev_node->data)) {
73 tbl = dev_node->data = hashtable_create(512, SIZEOF_INT64 == 8);
74 if (DEBUG_GTE(HLINK, 3)) {
76 "[%s] created hashtable for dev %s\n",
77 who_am_i(), big_num(dev));
83 return hashtable_find(tbl, ino, 1);
86 void idev_destroy(void)
90 for (i = 0; i < dev_tbl->size; i++) {
91 struct ht_int32_node *node = HT_NODE(dev_tbl, dev_tbl->nodes, i);
93 hashtable_destroy(node->data);
96 hashtable_destroy(dev_tbl);
99 static int hlink_compare_gnum(int *int1, int *int2)
101 struct file_struct *f1 = hlink_flist->sorted[*int1];
102 struct file_struct *f2 = hlink_flist->sorted[*int2];
103 int32 gnum1 = F_HL_GNUM(f1);
104 int32 gnum2 = F_HL_GNUM(f2);
107 return gnum1 > gnum2 ? 1 : -1;
109 return *int1 > *int2 ? 1 : -1;
112 static void match_gnums(int32 *ndx_list, int ndx_count)
115 struct file_struct *file, *file_next;
116 struct ht_int32_node *node = NULL;
117 int32 gnum, gnum_next;
119 qsort(ndx_list, ndx_count, sizeof ndx_list[0],
120 (int (*)()) hlink_compare_gnum);
122 for (from = 0; from < ndx_count; from++) {
123 file = hlink_flist->sorted[ndx_list[from]];
124 gnum = F_HL_GNUM(file);
126 node = hashtable_find(prior_hlinks, gnum, 1);
128 if (!(node->data = new_array0(char, 5)))
129 out_of_memory("match_gnums");
130 assert(gnum >= hlink_flist->ndx_start);
131 file->flags |= FLAG_HLINK_FIRST;
133 } else if (CVAL(node->data, 0) == 0) {
134 struct file_list *flist;
135 prev = IVAL(node->data, 1);
136 flist = flist_for_ndx(prev, NULL);
138 flist->files[prev - flist->ndx_start]->flags &= ~FLAG_HLINK_LAST;
140 /* We skipped all prior files in this
141 * group, so mark this as a "first". */
142 file->flags |= FLAG_HLINK_FIRST;
148 file->flags |= FLAG_HLINK_FIRST;
151 for ( ; from < ndx_count-1; file = file_next, gnum = gnum_next, from++) { /*SHARED ITERATOR*/
152 file_next = hlink_flist->sorted[ndx_list[from+1]];
153 gnum_next = F_HL_GNUM(file_next);
154 if (gnum != gnum_next)
156 F_HL_PREV(file) = prev;
157 /* The linked list uses over-the-wire ndx values. */
161 prev = ndx_list[from] + hlink_flist->ndx_start;
163 if (prev < 0 && !inc_recurse) {
164 /* Disable hard-link bit and set DONE so that
165 * HLINK_BUMP()-dependent values are unaffected. */
166 file->flags &= ~(FLAG_HLINKED | FLAG_HLINK_FIRST);
167 file->flags |= FLAG_HLINK_DONE;
171 file->flags |= FLAG_HLINK_LAST;
172 F_HL_PREV(file) = prev;
173 if (inc_recurse && CVAL(node->data, 0) == 0) {
177 prev = ndx_list[from] + hlink_flist->ndx_start;
178 SIVAL(node->data, 1, prev);
183 /* Analyze the hard-links in the file-list by creating a list of all the
184 * items that have hlink data, sorting them, and matching up identical
185 * values into clusters. These will be a single linked list from last
186 * to first when we're done. */
187 void match_hard_links(struct file_list *flist)
189 if (!list_only && flist->used) {
190 int i, ndx_count = 0;
193 if (!(ndx_list = new_array(int32, flist->used)))
194 out_of_memory("match_hard_links");
196 for (i = 0; i < flist->used; i++) {
197 if (F_IS_HLINKED(flist->sorted[i]))
198 ndx_list[ndx_count++] = i;
204 match_gnums(ndx_list, ndx_count);
208 if (protocol_version < 30)
212 static int maybe_hard_link(struct file_struct *file, int ndx,
213 const char *fname, int statret, stat_x *sxp,
214 const char *oldname, STRUCT_STAT *old_stp,
215 const char *realname, int itemizing, enum logcode code)
218 if (sxp->st.st_dev == old_stp->st_dev
219 && sxp->st.st_ino == old_stp->st_ino) {
221 itemize(fname, file, ndx, statret, sxp,
222 ITEM_LOCAL_CHANGE | ITEM_XNAME_FOLLOWS,
225 if (INFO_GTE(NAME, 2) && maybe_ATTRS_REPORT)
226 rprintf(FCLIENT, "%s is uptodate\n", fname);
227 file->flags |= FLAG_HLINK_DONE;
230 if (make_backups > 0) {
231 if (!make_backup(fname))
233 } else if (robust_unlink(fname)) {
234 rsyserr(FERROR_XFER, errno, "unlink %s failed",
240 if (hard_link_one(file, fname, oldname, 0)) {
242 itemize(fname, file, ndx, statret, sxp,
243 ITEM_LOCAL_CHANGE | ITEM_XNAME_FOLLOWS, 0,
246 if (code != FNONE && INFO_GTE(NAME, 1))
247 rprintf(code, "%s => %s\n", fname, realname);
253 /* Figure out if a prior entry is still there or if we just have a
254 * cached name for it. */
255 static char *check_prior(struct file_struct *file, int gnum,
256 int *prev_ndx_p, struct file_list **flist_p)
258 struct file_struct *fp;
259 struct ht_int32_node *node;
260 int prev_ndx = F_HL_PREV(file);
263 struct file_list *flist;
265 || (flist = flist_for_ndx(prev_ndx, NULL)) == NULL)
267 fp = flist->files[prev_ndx - flist->ndx_start];
268 if (!(fp->flags & FLAG_SKIP_HLINK)) {
269 *prev_ndx_p = prev_ndx;
273 F_HL_PREV(file) = prev_ndx = F_HL_PREV(fp);
277 && (node = hashtable_find(prior_hlinks, gnum, 0)) != NULL) {
278 assert(node->data != NULL);
279 if (CVAL(node->data, 0) != 0) {
284 /* The prior file must have been skipped. */
285 F_HL_PREV(file) = -1;
293 /* Only called if FLAG_HLINKED is set and FLAG_HLINK_FIRST is not. Returns:
294 * 0 = process the file, 1 = skip the file, -1 = error occurred. */
295 int hard_link_check(struct file_struct *file, int ndx, const char *fname,
296 int statret, stat_x *sxp, int itemizing,
300 char namebuf[MAXPATHLEN], altbuf[MAXPATHLEN];
301 char *realname, *prev_name;
302 struct file_list *flist;
303 int gnum = inc_recurse ? F_HL_GNUM(file) : -1;
306 prev_name = realname = check_prior(file, gnum, &prev_ndx, &flist);
309 struct file_struct *prev_file;
312 /* The previous file was skipped, so this one is
313 * treated as if it were the first in its group. */
314 if (DEBUG_GTE(HLINK, 2)) {
315 rprintf(FINFO, "hlink for %d (%s,%d): virtual first\n",
316 ndx, f_name(file, NULL), gnum);
321 prev_file = flist->files[prev_ndx - flist->ndx_start];
323 /* Is the previous link not complete yet? */
324 if (!(prev_file->flags & FLAG_HLINK_DONE)) {
325 /* Is the previous link being transferred? */
326 if (prev_file->flags & FLAG_FILE_SENT) {
327 /* Add ourselves to the list of files that will
328 * be updated when the transfer completes, and
329 * mark ourself as waiting for the transfer. */
330 F_HL_PREV(file) = F_HL_PREV(prev_file);
331 F_HL_PREV(prev_file) = ndx;
332 file->flags |= FLAG_FILE_SENT;
333 cur_flist->in_progress++;
334 if (DEBUG_GTE(HLINK, 2)) {
335 rprintf(FINFO, "hlink for %d (%s,%d): waiting for %d\n",
336 ndx, f_name(file, NULL), gnum, F_HL_PREV(file));
340 if (DEBUG_GTE(HLINK, 2)) {
341 rprintf(FINFO, "hlink for %d (%s,%d): looking for a leader\n",
342 ndx, f_name(file, NULL), gnum);
347 /* There is a finished file to link with! */
348 if (!(prev_file->flags & FLAG_HLINK_FIRST)) {
349 /* The previous previous is FIRST when prev is not. */
350 prev_name = realname = check_prior(prev_file, gnum, &prev_ndx, &flist);
351 /* Update our previous pointer to point to the FIRST. */
352 F_HL_PREV(file) = prev_ndx;
358 assert(flist != NULL);
359 prev_file = flist->files[prev_ndx - flist->ndx_start];
360 /* F_HL_PREV() is alt_dest value when DONE && FIRST. */
361 alt_dest = F_HL_PREV(prev_file);
362 if (DEBUG_GTE(HLINK, 2)) {
363 rprintf(FINFO, "hlink for %d (%s,%d): found flist match (alt %d)\n",
364 ndx, f_name(file, NULL), gnum, alt_dest);
367 if (alt_dest >= 0 && dry_run) {
368 pathjoin(namebuf, MAXPATHLEN, basis_dir[alt_dest],
369 f_name(prev_file, NULL));
371 realname = f_name(prev_file, altbuf);
373 prev_name = f_name(prev_file, namebuf);
374 realname = prev_name;
379 if (DEBUG_GTE(HLINK, 2)) {
380 rprintf(FINFO, "hlink for %d (%s,%d): leader is %d (%s)\n",
381 ndx, f_name(file, NULL), gnum, prev_ndx, prev_name);
384 if (link_stat(prev_name, &prev_st, 0) < 0) {
385 rsyserr(FERROR_XFER, errno, "stat %s failed",
386 full_fname(prev_name));
390 if (statret < 0 && basis_dir[0] != NULL) {
391 /* If we match an alt-dest item, we don't output this as a change. */
392 char cmpbuf[MAXPATHLEN];
396 alt_sx.acc_acl = alt_sx.def_acl = NULL;
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)) {
426 if (!ACL_READY(*sxp))
427 get_acl(cmpbuf, sxp);
429 sxp->acc_acl = alt_sx.acc_acl;
430 sxp->def_acl = alt_sx.def_acl;
436 else if (preserve_acls)
441 if (maybe_hard_link(file, ndx, fname, statret, sxp, prev_name, &prev_st,
442 realname, itemizing, code) < 0)
445 if (remove_source_files == 1 && do_xfers)
446 send_msg_int(MSG_SUCCESS, ndx);
451 int hard_link_one(struct file_struct *file, const char *fname,
452 const char *oldname, int terse)
454 if (do_link(oldname, fname) < 0) {
457 if (!INFO_GTE(NAME, 1))
462 rsyserr(code, errno, "link %s => %s failed",
463 full_fname(fname), oldname);
467 file->flags |= FLAG_HLINK_DONE;
472 void finish_hard_link(struct file_struct *file, const char *fname, int fin_ndx,
473 STRUCT_STAT *stp, int itemizing, enum logcode code,
478 char prev_name[MAXPATHLEN], alt_name[MAXPATHLEN];
479 const char *our_name;
480 struct file_list *flist;
481 int prev_statret, ndx, prev_ndx = F_HL_PREV(file);
483 if (stp == NULL && prev_ndx >= 0) {
484 if (link_stat(fname, &st, 0) < 0) {
485 rsyserr(FERROR_XFER, errno, "stat %s failed",
492 /* FIRST combined with DONE means we were the first to get done. */
493 file->flags |= FLAG_HLINK_FIRST | FLAG_HLINK_DONE;
494 F_HL_PREV(file) = alt_dest;
495 if (alt_dest >= 0 && dry_run) {
496 pathjoin(alt_name, MAXPATHLEN, basis_dir[alt_dest],
503 prev_sx.acc_acl = prev_sx.def_acl = NULL;
506 while ((ndx = prev_ndx) >= 0) {
508 flist = flist_for_ndx(ndx, "finish_hard_link");
509 file = flist->files[ndx - flist->ndx_start];
510 file->flags = (file->flags & ~FLAG_HLINK_FIRST) | FLAG_HLINK_DONE;
511 prev_ndx = F_HL_PREV(file);
512 F_HL_PREV(file) = fin_ndx;
513 prev_statret = link_stat(f_name(file, prev_name), &prev_sx.st, 0);
514 val = maybe_hard_link(file, ndx, prev_name, prev_statret, &prev_sx,
515 our_name, stp, fname, itemizing, code);
516 flist->in_progress--;
523 if (remove_source_files == 1 && do_xfers)
524 send_msg_int(MSG_SUCCESS, ndx);
528 int gnum = F_HL_GNUM(file);
529 struct ht_int32_node *node = hashtable_find(prior_hlinks, gnum, 0);
530 assert(node != NULL && node->data != NULL);
531 assert(CVAL(node->data, 0) == 0);
533 if (!(node->data = strdup(our_name)))
534 out_of_memory("finish_hard_link");
538 int skip_hard_link(struct file_struct *file, struct file_list **flist_p)
540 struct file_list *flist;
543 file->flags |= FLAG_SKIP_HLINK;
544 if (!(file->flags & FLAG_HLINK_LAST))
547 check_prior(file, F_HL_GNUM(file), &prev_ndx, &flist);
549 file = flist->files[prev_ndx - flist->ndx_start];
550 if (file->flags & (FLAG_HLINK_DONE|FLAG_FILE_SENT))
552 file->flags |= FLAG_HLINK_LAST;