hlink.c

   1 /*
   2    Copyright (C) Andrew Tridgell 1996
   3    Copyright (C) Paul Mackerras 1996
   4    Copyright (C) 2002 by Martin Pool <mbp@samba.org>
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 2 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program; if not, write to the Free Software
  18    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  19 */
  20
  21 #include "rsync.h"
  22
  23 extern int dry_run;
  24 extern int verbose;
  25 extern int make_backups;
  26 extern struct file_list *the_file_list;
  27
  28 #ifdef SUPPORT_HARD_LINKS
  29
  30 #define FPTR(i) (the_file_list->files[i])
  31 #define LINKED(p1,p2) (FPTR(p1)->F_DEV == FPTR(p2)->F_DEV \
  32                     && FPTR(p1)->F_INODE == FPTR(p2)->F_INODE)
  33
  34 static int hlink_compare(int *int1, int *int2)
  35 {
  36         struct file_struct *f1 = FPTR(*int1);
  37         struct file_struct *f2 = FPTR(*int2);
  38
  39         if (f1->F_DEV != f2->F_DEV)
  40                 return (int) (f1->F_DEV > f2->F_DEV ? 1 : -1);
  41
  42         if (f1->F_INODE != f2->F_INODE)
  43                 return (int) (f1->F_INODE > f2->F_INODE ? 1 : -1);
  44
  45         return f_name_cmp(f1, f2);
  46 }
  47
  48 static int *hlink_list;
  49 static int hlink_count;
  50
  51 /* Analyze the data in the hlink_list[], remove items that aren't multiply
  52  * linked, and replace the dev+inode data with the hlindex+next linked list. */
  53 static void link_idev_data(void)
  54 {
  55         int head, from, to, start;
  56
  57         alloc_pool_t hlink_pool;
  58         alloc_pool_t idev_pool = the_file_list->hlink_pool;
  59
  60         hlink_pool = pool_create(128 * 1024, sizeof (struct hlink),
  61             out_of_memory, POOL_INTERN);
  62
  63         for (from = to = 0; from < hlink_count; from++) {
  64                 start = from;
  65                 head = hlink_list[start];
  66                 while (from < hlink_count-1
  67                     && LINKED(hlink_list[from], hlink_list[from+1])) {
  68                         pool_free(idev_pool, 0, FPTR(hlink_list[from])->link_u.idev);
  69                         FPTR(hlink_list[from])->link_u.links = pool_talloc(hlink_pool,
  70                             struct hlink, 1, "hlink_list");
  71
  72                         FPTR(hlink_list[from])->F_HLINDEX = to;
  73                         FPTR(hlink_list[from])->F_NEXT = hlink_list[from+1];
  74                         from++;
  75                 }
  76                 if (from > start) {
  77                         pool_free(idev_pool, 0, FPTR(hlink_list[from])->link_u.idev);
  78                         FPTR(hlink_list[from])->link_u.links = pool_talloc(hlink_pool,
  79                             struct hlink, 1, "hlink_list");
  80
  81                         FPTR(head)->flags |= FLAG_HLINK_TOL;
  82                         FPTR(hlink_list[from])->F_HLINDEX = to;
  83                         FPTR(hlink_list[from])->F_NEXT = head;
  84                         FPTR(hlink_list[from])->flags |= FLAG_HLINK_EOL;
  85                         hlink_list[to++] = head;
  86                 } else {
  87                         pool_free(idev_pool, 0, FPTR(head)->link_u.idev);
  88                         FPTR(head)->link_u.idev = NULL;
  89                 }
  90         }
  91
  92         if (!to) {
  93                 free(hlink_list);
  94                 hlink_list = NULL;
  95                 pool_destroy(hlink_pool);
  96                 hlink_pool = NULL;
  97         } else {
  98                 hlink_count = to;
  99                 hlink_list = realloc_array(hlink_list, int, hlink_count);
 100                 if (!hlink_list)
 101                         out_of_memory("init_hard_links");
 102         }
 103         the_file_list->hlink_pool = hlink_pool;
 104         pool_destroy(idev_pool);
 105 }
 106 #endif
 107
 108 void init_hard_links(void)
 109 {
 110 #ifdef SUPPORT_HARD_LINKS
 111         int i;
 112
 113         if (the_file_list->count < 2)
 114                 return;
 115
 116         if (hlink_list)
 117                 free(hlink_list);
 118
 119         if (!(hlink_list = new_array(int, the_file_list->count)))
 120                 out_of_memory("init_hard_links");
 121
 122         hlink_count = 0;
 123         for (i = 0; i < the_file_list->count; i++) {
 124                 if (FPTR(i)->link_u.idev)
 125                         hlink_list[hlink_count++] = i;
 126         }
 127
 128         qsort(hlink_list, hlink_count,
 129             sizeof hlink_list[0], (int (*)()) hlink_compare);
 130
 131         if (!hlink_count) {
 132                 free(hlink_list);
 133                 hlink_list = NULL;
 134         } else
 135                 link_idev_data();
 136 #endif
 137 }
 138
 139 int hard_link_check(struct file_struct *file, int ndx, int skip)
 140 {
 141 #ifdef SUPPORT_HARD_LINKS
 142         if (!hlink_list || !file->link_u.links)
 143                 return 0;
 144         if (skip && !(file->flags & FLAG_HLINK_EOL))
 145                 hlink_list[file->F_HLINDEX] = file->F_NEXT;
 146         if (hlink_list[file->F_HLINDEX] != ndx) {
 147                 if (verbose > 2) {
 148                         rprintf(FINFO, "\"%s\" is a hard link\n",
 149                                 safe_fname(f_name(file)));
 150                 }
 151                 return 1;
 152         }
 153 #endif
 154         return 0;
 155 }
 156
 157 #ifdef SUPPORT_HARD_LINKS
 158 int hard_link_one(struct file_struct *file, int ndx, char *fname,
 159                   int statret, STRUCT_STAT *st, char *toname, int terse,
 160                   int itemizing, enum logcode code)
 161 {
 162         if (do_link(toname, fname)) {
 163                 if (verbose) {
 164                         rsyserr(FERROR, errno, "link %s => %s failed",
 165                                 full_fname(fname), safe_fname(toname));
 166                 }
 167                 return -1;
 168         }
 169
 170         if (itemizing) {
 171                 itemize(file, ndx, statret, st,
 172                         ITEM_LOCAL_CHANGE | ITEM_XNAME_FOLLOWS, 0,
 173                         terse ? "" : toname);
 174         }
 175         if (code && verbose && !terse) {
 176                 rprintf(code, "%s => %s\n",
 177                         safe_fname(fname), safe_fname(toname));
 178         }
 179         return 0;
 180 }
 181 #endif
 182
 183
 184 void hard_link_cluster(struct file_struct *file, int master, int itemizing,
 185                        enum logcode code)
 186 {
 187 #ifdef SUPPORT_HARD_LINKS
 188         char hlink1[MAXPATHLEN];
 189         char *hlink2;
 190         STRUCT_STAT st1, st2;
 191         int statret, ndx = master;
 192
 193         if (link_stat(f_name_to(file, hlink1), &st1, 0) < 0)
 194                 return;
 195         if (!(file->flags & FLAG_HLINK_TOL)) {
 196                 while (!(file->flags & FLAG_HLINK_EOL)) {
 197                         ndx = file->F_NEXT;
 198                         file = FPTR(ndx);
 199                 }
 200         }
 201         do {
 202                 ndx = file->F_NEXT;
 203                 file = FPTR(ndx);
 204                 if (ndx == master)
 205                         continue;
 206                 hlink2 = f_name(file);
 207                 if ((statret = link_stat(hlink2, &st2, 0)) == 0) {
 208                         if (st2.st_dev == st1.st_dev
 209                             && st2.st_ino == st1.st_ino) {
 210                                 if (itemizing) {
 211                                         itemize(file, ndx, statret, &st2,
 212                                                 ITEM_LOCAL_CHANGE | ITEM_XNAME_FOLLOWS,
 213                                                 0, "");
 214                                 }
 215                                 continue;
 216                         }
 217                         if (make_backups) {
 218                                 if (!make_backup(hlink2))
 219                                         continue;
 220                         } else if (robust_unlink(hlink2)) {
 221                                 if (verbose > 0) {
 222                                         rsyserr(FINFO, errno,
 223                                                 "unlink %s failed",
 224                                                 full_fname(hlink2));
 225                                 }
 226                                 continue;
 227                         }
 228                 }
 229                 hard_link_one(file, ndx, hlink2, statret,
 230                               &st2, hlink1, 0, itemizing, code);
 231         } while (!(file->flags & FLAG_HLINK_EOL));
 232 #endif
 233 }