Report all socket connection errors if we fail.
[rsync.git] / hlink.c
1 /*
2  * Routines to support hard-linking.
3  *
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
8  *
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.
13  *
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.
18  *
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.
21  */
22
23 #include "rsync.h"
24
25 extern int verbose;
26 extern int dry_run;
27 extern int list_only;
28 extern int am_sender;
29 extern int inc_recurse;
30 extern int do_xfers;
31 extern int link_dest;
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;
42
43 #ifdef SUPPORT_HARD_LINKS
44
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. */
50
51 static struct hashtable *dev_tbl;
52
53 static struct hashtable *prior_hlinks;
54
55 static struct file_list *hlink_flist;
56
57 void init_hard_links(void)
58 {
59         if (am_sender || protocol_version < 30)
60                 dev_tbl = hashtable_create(16, 1);
61         else if (inc_recurse)
62                 prior_hlinks = hashtable_create(1024, 0);
63 }
64
65 struct ht_int64_node *idev_find(int64 dev, int64 ino)
66 {
67         static struct ht_int64_node *dev_node = NULL;
68         struct hashtable *tbl;
69
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         } else
77                 tbl = dev_node->data;
78
79         return hashtable_find(tbl, ino, 1);
80 }
81
82 void idev_destroy(void)
83 {
84         int i;
85
86         for (i = 0; i < dev_tbl->size; i++) {
87                 struct ht_int32_node *node = HT_NODE(dev_tbl, dev_tbl->nodes, i);
88                 if (node->data)
89                         hashtable_destroy(node->data);
90         }
91
92         hashtable_destroy(dev_tbl);
93 }
94
95 static int hlink_compare_gnum(int *int1, int *int2)
96 {
97         struct file_struct *f1 = hlink_flist->sorted[*int1];
98         struct file_struct *f2 = hlink_flist->sorted[*int2];
99         int32 gnum1 = F_HL_GNUM(f1);
100         int32 gnum2 = F_HL_GNUM(f2);
101
102         if (gnum1 != gnum2)
103                 return gnum1 > gnum2 ? 1 : -1;
104
105         return *int1 > *int2 ? 1 : -1;
106 }
107
108 static void match_gnums(int32 *ndx_list, int ndx_count)
109 {
110         int32 from, prev;
111         struct file_struct *file, *file_next;
112         struct ht_int32_node *node = NULL;
113         int32 gnum, gnum_next;
114
115         qsort(ndx_list, ndx_count, sizeof ndx_list[0],
116              (int (*)()) hlink_compare_gnum);
117
118         for (from = 0; from < ndx_count; from++) {
119                 file = hlink_flist->sorted[ndx_list[from]];
120                 gnum = F_HL_GNUM(file);
121                 if (inc_recurse) {
122                         node = hashtable_find(prior_hlinks, gnum, 1);
123                         if (!node->data) {
124                                 if (!(node->data = new_array0(char, 5)))
125                                         out_of_memory("match_gnums");
126                                 assert(gnum >= hlink_flist->ndx_start);
127                                 file->flags |= FLAG_HLINK_FIRST;
128                                 prev = -1;
129                         } else if (CVAL(node->data, 0) == 0) {
130                                 struct file_list *flist;
131                                 prev = IVAL(node->data, 1);
132                                 flist = flist_for_ndx(prev, NULL);
133                                 if (flist)
134                                         flist->files[prev - flist->ndx_start]->flags &= ~FLAG_HLINK_LAST;
135                                 else {
136                                         /* We skipped all prior files in this
137                                          * group, so mark this as a "first". */
138                                         file->flags |= FLAG_HLINK_FIRST;
139                                         prev = -1;
140                                 }
141                         } else
142                                 prev = -1;
143                 } else {
144                         file->flags |= FLAG_HLINK_FIRST;
145                         prev = -1;
146                 }
147                 for ( ; from < ndx_count-1; file = file_next, gnum = gnum_next, from++) { /*SHARED ITERATOR*/
148                         file_next = hlink_flist->sorted[ndx_list[from+1]];
149                         gnum_next = F_HL_GNUM(file_next);
150                         if (gnum != gnum_next)
151                                 break;
152                         F_HL_PREV(file) = prev;
153                         /* The linked list uses over-the-wire ndx values. */
154                         if (unsort_ndx)
155                                 prev = F_NDX(file);
156                         else
157                                 prev = ndx_list[from] + hlink_flist->ndx_start;
158                 }
159                 if (prev < 0 && !inc_recurse) {
160                         /* Disable hard-link bit and set DONE so that
161                          * HLINK_BUMP()-dependent values are unaffected. */
162                         file->flags &= ~(FLAG_HLINKED | FLAG_HLINK_FIRST);
163                         file->flags |= FLAG_HLINK_DONE;
164                         continue;
165                 }
166
167                 file->flags |= FLAG_HLINK_LAST;
168                 F_HL_PREV(file) = prev;
169                 if (inc_recurse && CVAL(node->data, 0) == 0) {
170                         if (unsort_ndx)
171                                 prev = F_NDX(file);
172                         else
173                                 prev = ndx_list[from] + hlink_flist->ndx_start;
174                         SIVAL(node->data, 1, prev);
175                 }
176         }
177 }
178
179 /* Analyze the hard-links in the file-list by creating a list of all the
180  * items that have hlink data, sorting them, and matching up identical
181  * values into clusters.  These will be a single linked list from last
182  * to first when we're done. */
183 void match_hard_links(struct file_list *flist)
184 {
185         if (!list_only && flist->used) {
186                 int i, ndx_count = 0;
187                 int32 *ndx_list;
188
189                 if (!(ndx_list = new_array(int32, flist->used)))
190                         out_of_memory("match_hard_links");
191
192                 for (i = 0; i < flist->used; i++) {
193                         if (F_IS_HLINKED(flist->sorted[i]))
194                                 ndx_list[ndx_count++] = i;
195                 }
196
197                 hlink_flist = flist;
198
199                 if (ndx_count)
200                         match_gnums(ndx_list, ndx_count);
201
202                 free(ndx_list);
203         }
204         if (protocol_version < 30)
205                 idev_destroy();
206 }
207
208 static int maybe_hard_link(struct file_struct *file, int ndx,
209                            const char *fname, int statret, stat_x *sxp,
210                            const char *oldname, STRUCT_STAT *old_stp,
211                            const char *realname, int itemizing, enum logcode code)
212 {
213         if (statret == 0) {
214                 if (sxp->st.st_dev == old_stp->st_dev
215                  && sxp->st.st_ino == old_stp->st_ino) {
216                         if (itemizing) {
217                                 itemize(fname, file, ndx, statret, sxp,
218                                         ITEM_LOCAL_CHANGE | ITEM_XNAME_FOLLOWS,
219                                         0, "");
220                         }
221                         if (verbose > 1 && maybe_ATTRS_REPORT)
222                                 rprintf(FCLIENT, "%s is uptodate\n", fname);
223                         file->flags |= FLAG_HLINK_DONE;
224                         return 0;
225                 }
226                 if (make_backups > 0) {
227                         if (!make_backup(fname))
228                                 return -1;
229                 } else if (robust_unlink(fname)) {
230                         rsyserr(FERROR_XFER, errno, "unlink %s failed",
231                                 full_fname(fname));
232                         return -1;
233                 }
234         }
235
236         if (hard_link_one(file, fname, oldname, 0)) {
237                 if (itemizing) {
238                         itemize(fname, file, ndx, statret, sxp,
239                                 ITEM_LOCAL_CHANGE | ITEM_XNAME_FOLLOWS, 0,
240                                 realname);
241                 }
242                 if (code != FNONE && verbose)
243                         rprintf(code, "%s => %s\n", fname, realname);
244                 return 0;
245         }
246         return -1;
247 }
248
249 /* Figure out if a prior entry is still there or if we just have a
250  * cached name for it. */
251 static char *check_prior(struct file_struct *file, int gnum,
252                          int *prev_ndx_p, struct file_list **flist_p)
253 {
254         struct file_struct *fp;
255         struct ht_int32_node *node;
256         int prev_ndx = F_HL_PREV(file);
257
258         while (1) {
259                 struct file_list *flist;
260                 if (prev_ndx < 0
261                  || (flist = flist_for_ndx(prev_ndx, NULL)) == NULL)
262                         break;
263                 fp = flist->files[prev_ndx - flist->ndx_start];
264                 if (!(fp->flags & FLAG_SKIP_HLINK)) {
265                         *prev_ndx_p = prev_ndx;
266                         *flist_p = flist;
267                         return NULL;
268                 }
269                 F_HL_PREV(file) = prev_ndx = F_HL_PREV(fp);
270         }
271
272         if (inc_recurse
273          && (node = hashtable_find(prior_hlinks, gnum, 0)) != NULL) {
274                 assert(node->data != NULL);
275                 if (CVAL(node->data, 0) != 0) {
276                         *prev_ndx_p = -1;
277                         *flist_p = NULL;
278                         return node->data;
279                 }
280                 /* The prior file must have been skipped. */
281                 F_HL_PREV(file) = -1;
282         }
283
284         *prev_ndx_p = -1;
285         *flist_p = NULL;
286         return NULL;
287 }
288
289 /* Only called if FLAG_HLINKED is set and FLAG_HLINK_FIRST is not.  Returns:
290  * 0 = process the file, 1 = skip the file, -1 = error occurred. */
291 int hard_link_check(struct file_struct *file, int ndx, const char *fname,
292                     int statret, stat_x *sxp, int itemizing,
293                     enum logcode code)
294 {
295         STRUCT_STAT prev_st;
296         char namebuf[MAXPATHLEN], altbuf[MAXPATHLEN];
297         char *realname, *prev_name;
298         struct file_list *flist;
299         int gnum = inc_recurse ? F_HL_GNUM(file) : -1;
300         int prev_ndx;
301
302         prev_name = realname = check_prior(file, gnum, &prev_ndx, &flist);
303
304         if (!prev_name) {
305                 struct file_struct *prev_file;
306
307                 if (!flist) {
308                         /* The previous file was skipped, so this one is
309                          * treated as if it were the first in its group. */
310                         return 0;
311                 }
312
313                 prev_file = flist->files[prev_ndx - flist->ndx_start];
314
315                 /* Is the previous link not complete yet? */
316                 if (!(prev_file->flags & FLAG_HLINK_DONE)) {
317                         /* Is the previous link being transferred? */
318                         if (prev_file->flags & FLAG_FILE_SENT) {
319                                 /* Add ourselves to the list of files that will
320                                  * be updated when the transfer completes, and
321                                  * mark ourself as waiting for the transfer. */
322                                 F_HL_PREV(file) = F_HL_PREV(prev_file);
323                                 F_HL_PREV(prev_file) = ndx;
324                                 file->flags |= FLAG_FILE_SENT;
325                                 cur_flist->in_progress++;
326                                 return 1;
327                         }
328                         return 0;
329                 }
330
331                 /* There is a finished file to link with! */
332                 if (!(prev_file->flags & FLAG_HLINK_FIRST)) {
333                         /* The previous previous is FIRST when prev is not. */
334                         prev_name = realname = check_prior(prev_file, gnum, &prev_ndx, &flist);
335                         assert(prev_name != NULL || flist != NULL);
336                         /* Update our previous pointer to point to the FIRST. */
337                         F_HL_PREV(file) = prev_ndx;
338                 }
339
340                 if (!prev_name) {
341                         int alt_dest;
342
343                         prev_file = flist->files[prev_ndx - flist->ndx_start];
344                         /* F_HL_PREV() is alt_dest value when DONE && FIRST. */
345                         alt_dest = F_HL_PREV(prev_file);
346
347                         if (alt_dest >= 0 && dry_run) {
348                                 pathjoin(namebuf, MAXPATHLEN, basis_dir[alt_dest],
349                                          f_name(prev_file, NULL));
350                                 prev_name = namebuf;
351                                 realname = f_name(prev_file, altbuf);
352                         } else {
353                                 prev_name = f_name(prev_file, namebuf);
354                                 realname = prev_name;
355                         }
356                 }
357         }
358
359         if (link_stat(prev_name, &prev_st, 0) < 0) {
360                 if (!dry_run || errno != ENOENT) {
361                         rsyserr(FERROR_XFER, errno, "stat %s failed", full_fname(prev_name));
362                         return -1;
363                 }
364                 /* A new hard-link will get a new dev & inode, so approximate
365                  * those values in dry-run mode by zeroing them. */
366                 memset(&prev_st, 0, sizeof prev_st);
367         }
368
369         if (statret < 0 && basis_dir[0] != NULL) {
370                 /* If we match an alt-dest item, we don't output this as a change. */
371                 char cmpbuf[MAXPATHLEN];
372                 stat_x alt_sx;
373                 int j = 0;
374 #ifdef SUPPORT_ACLS
375                 alt_sx.acc_acl = alt_sx.def_acl = NULL;
376 #endif
377 #ifdef SUPPORT_XATTRS
378                 alt_sx.xattr = NULL;
379 #endif
380                 do {
381                         pathjoin(cmpbuf, MAXPATHLEN, basis_dir[j], fname);
382                         if (link_stat(cmpbuf, &alt_sx.st, 0) < 0)
383                                 continue;
384                         if (link_dest) {
385                                 if (prev_st.st_dev != alt_sx.st.st_dev
386                                  || prev_st.st_ino != alt_sx.st.st_ino)
387                                         continue;
388                                 statret = 1;
389                                 if (stdout_format_has_i == 0
390                                  || (verbose < 2 && stdout_format_has_i < 2)) {
391                                         itemizing = 0;
392                                         code = FNONE;
393                                         if (verbose > 1 && maybe_ATTRS_REPORT)
394                                                 rprintf(FCLIENT, "%s is uptodate\n", fname);
395                                 }
396                                 break;
397                         }
398                         if (!unchanged_file(cmpbuf, file, &alt_sx.st))
399                                 continue;
400                         statret = 1;
401                         if (unchanged_attrs(cmpbuf, file, &alt_sx))
402                                 break;
403                 } while (basis_dir[++j] != NULL);
404                 if (statret == 1) {
405                         sxp->st = alt_sx.st;
406 #ifdef SUPPORT_ACLS
407                         if (preserve_acls && !S_ISLNK(file->mode)) {
408                                 free_acl(sxp);
409                                 if (!ACL_READY(alt_sx))
410                                         get_acl(cmpbuf, sxp);
411                                 else {
412                                         sxp->acc_acl = alt_sx.acc_acl;
413                                         sxp->def_acl = alt_sx.def_acl;
414                                         alt_sx.acc_acl = alt_sx.def_acl = NULL;
415                                 }
416                         }
417 #endif
418 #ifdef SUPPORT_XATTRS
419                         if (preserve_xattrs) {
420                                 free_xattr(sxp);
421                                 if (!XATTR_READY(alt_sx))
422                                         get_xattr(cmpbuf, sxp);
423                                 else {
424                                         sxp->xattr = alt_sx.xattr;
425                                         alt_sx.xattr = NULL;
426                                 }
427                         }
428 #endif
429                 } else {
430 #ifdef SUPPORT_ACLS
431                         if (preserve_acls)
432                                 free_acl(&alt_sx);
433 #endif
434 #ifdef SUPPORT_XATTRS
435                         if (preserve_xattrs)
436                                 free_xattr(&alt_sx);
437 #endif
438                 }
439         }
440
441         if (maybe_hard_link(file, ndx, fname, statret, sxp, prev_name, &prev_st,
442                             realname, itemizing, code) < 0)
443                 return -1;
444
445         if (remove_source_files == 1 && do_xfers)
446                 send_msg_int(MSG_SUCCESS, ndx);
447
448         return 1;
449 }
450
451 int hard_link_one(struct file_struct *file, const char *fname,
452                   const char *oldname, int terse)
453 {
454         if (do_link(oldname, fname) < 0) {
455                 enum logcode code;
456                 if (terse) {
457                         if (!verbose)
458                                 return 0;
459                         code = FINFO;
460                 } else
461                         code = FERROR_XFER;
462                 rsyserr(code, errno, "link %s => %s failed",
463                         full_fname(fname), oldname);
464                 return 0;
465         }
466
467         file->flags |= FLAG_HLINK_DONE;
468
469         return 1;
470 }
471
472 void finish_hard_link(struct file_struct *file, const char *fname, int fin_ndx,
473                       STRUCT_STAT *stp, int itemizing, enum logcode code,
474                       int alt_dest)
475 {
476         stat_x prev_sx;
477         STRUCT_STAT st;
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);
482
483         if (stp == NULL && prev_ndx >= 0) {
484                 if (link_stat(fname, &st, 0) < 0) {
485                         rsyserr(FERROR_XFER, errno, "stat %s failed",
486                                 full_fname(fname));
487                         return;
488                 }
489                 stp = &st;
490         }
491
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],
497                          f_name(file, NULL));
498                 our_name = alt_name;
499         } else
500                 our_name = fname;
501
502 #ifdef SUPPORT_ACLS
503         prev_sx.acc_acl = prev_sx.def_acl = NULL;
504 #endif
505 #ifdef SUPPORT_XATTRS
506         prev_sx.xattr = NULL;
507 #endif
508
509         while ((ndx = prev_ndx) >= 0) {
510                 int val;
511                 flist = flist_for_ndx(ndx, "finish_hard_link");
512                 file = flist->files[ndx - flist->ndx_start];
513                 file->flags = (file->flags & ~FLAG_HLINK_FIRST) | FLAG_HLINK_DONE;
514                 prev_ndx = F_HL_PREV(file);
515                 F_HL_PREV(file) = fin_ndx;
516                 prev_statret = link_stat(f_name(file, prev_name), &prev_sx.st, 0);
517                 val = maybe_hard_link(file, ndx, prev_name, prev_statret, &prev_sx,
518                                       our_name, stp, fname, itemizing, code);
519                 flist->in_progress--;
520 #ifdef SUPPORT_ACLS
521                 if (preserve_acls)
522                         free_acl(&prev_sx);
523 #endif
524 #ifdef SUPPORT_XATTRS
525                 if (preserve_xattrs)
526                         free_xattr(&prev_sx);
527 #endif
528                 if (val < 0)
529                         continue;
530                 if (remove_source_files == 1 && do_xfers)
531                         send_msg_int(MSG_SUCCESS, ndx);
532         }
533
534         if (inc_recurse) {
535                 int gnum = F_HL_GNUM(file);
536                 struct ht_int32_node *node = hashtable_find(prior_hlinks, gnum, 0);
537                 if (node == NULL) {
538                         rprintf(FERROR, "Unable to find a hlink node for %d (%s)\n", gnum, f_name(file, prev_name));
539                         exit_cleanup(RERR_MESSAGEIO);
540                 }
541                 if (node->data == NULL) {
542                         rprintf(FERROR, "Hlink node data for %d is NULL (%s)\n", gnum, f_name(file, prev_name));
543                         exit_cleanup(RERR_MESSAGEIO);
544                 }
545                 if (CVAL(node->data, 0) != 0) {
546                         rprintf(FERROR, "Hlink node data for %d already has path=%s (%s)\n",
547                                 gnum, (char*)node->data, f_name(file, prev_name));
548                         exit_cleanup(RERR_MESSAGEIO);
549                 }
550                 free(node->data);
551                 if (!(node->data = strdup(our_name)))
552                         out_of_memory("finish_hard_link");
553         }
554 }
555
556 int skip_hard_link(struct file_struct *file, struct file_list **flist_p)
557 {
558         struct file_list *flist;
559         int prev_ndx;
560
561         file->flags |= FLAG_SKIP_HLINK;
562         if (!(file->flags & FLAG_HLINK_LAST))
563                 return -1;
564
565         check_prior(file, F_HL_GNUM(file), &prev_ndx, &flist);
566         if (prev_ndx >= 0) {
567                 file = flist->files[prev_ndx - flist->ndx_start];
568                 if (file->flags & (FLAG_HLINK_DONE|FLAG_FILE_SENT))
569                         return -1;
570                 file->flags |= FLAG_HLINK_LAST;
571                 *flist_p = flist;
572         }
573
574         return prev_ndx;
575 }
576 #endif