Close the socket fds in the "post-xfer exec" process.
[rsync/rsync.git] / backup.c
CommitLineData
addf0c4a 1/*
0f78b815
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2 * Backup handling code.
3 *
4 * Copyright (C) 1999 Andrew Tridgell
b3bf9b9d 5 * Copyright (C) 2003-2009 Wayne Davison
0f78b815
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6 *
7 * This program is free software; you can redistribute it and/or modify
8e41b68e
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8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 3 of the License, or
10 * (at your option) any later version.
0f78b815
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11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 *
e7c67065 17 * You should have received a copy of the GNU General Public License along
4fd842f9 18 * with this program; if not, visit the http://fsf.org website.
0f78b815 19 */
3d19b4c8
AT
20
21#include "rsync.h"
09ca0d15 22#include "ifuncs.h"
3d19b4c8 23
378a074c 24extern int am_root;
1c3344a1 25extern int preserve_acls;
16edf865 26extern int preserve_xattrs;
378a074c 27extern int preserve_devices;
b5c6a6ae 28extern int preserve_specials;
378a074c 29extern int preserve_links;
377dbd20 30extern int safe_symlinks;
6b2a3d5d 31extern int backup_dir_len;
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32extern unsigned int backup_dir_remainder;
33extern char backup_dir_buf[MAXPATHLEN];
34extern char *backup_suffix;
35extern char *backup_dir;
378a074c 36
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37/* Returns -1 on error, 0 on missing dir, and 1 on present dir. */
38static int validate_backup_dir(void)
39{
40 STRUCT_STAT st;
41
42 if (do_lstat(backup_dir_buf, &st) < 0) {
43 if (errno == ENOENT)
44 return 0;
45 rsyserr(FERROR, errno, "backup lstat %s failed", backup_dir_buf);
46 return -1;
47 }
48 if (!S_ISDIR(st.st_mode)) {
49 int flags = get_del_for_flag(st.st_mode) | DEL_FOR_BACKUP | DEL_RECURSE;
50 if (delete_item(backup_dir_buf, st.st_mode, flags) == 0)
51 return 0;
52 return -1;
53 }
54 return 1;
55}
56
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WD
57/* Create a backup path from the given fname, putting the result into
58 * backup_dir_buf. Any new directories (compared to the prior backup
59 * path) are ensured to exist as directories, replacing anything else
60 * that may be in the way (e.g. a symlink). */
61static BOOL copy_valid_path(const char *fname)
378a074c 62{
3696674b 63 const char *f;
9b594a53 64 int val;
3696674b 65 BOOL ret = True;
13710874 66 stat_x sx;
3696674b 67 char *b, *rel = backup_dir_buf + backup_dir_len, *name = rel;
de0e2250 68
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69 for (f = fname, b = rel; *f && *f == *b; f++, b++) {
70 if (*b == '/')
71 name = b + 1;
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72 }
73
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74 if (stringjoin(rel, backup_dir_remainder, fname, backup_suffix, NULL) >= backup_dir_remainder) {
75 rprintf(FERROR, "backup filename too long\n");
76 *name = '\0';
77 return False;
78 }
e1ac7791 79
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80 for ( ; ; name = b + 1) {
81 if ((b = strchr(name, '/')) == NULL)
82 return True;
83 *b = '\0';
de0e2250 84
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85 val = validate_backup_dir();
86 if (val == 0)
87 break;
88 if (val < 0) {
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89 *name = '\0';
90 return False;
de0e2250 91 }
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92
93 *b = '/';
47d6a60c 94 }
de0e2250 95
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96 init_stat_x(&sx);
97
98 for ( ; b; name = b + 1, b = strchr(name, '/')) {
99 *b = '\0';
100
9fbec6e4 101 while (do_mkdir(backup_dir_buf, ACCESSPERMS) < 0) {
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102 if (errno == EEXIST) {
103 val = validate_backup_dir();
104 if (val > 0)
105 break;
106 if (val == 0)
107 continue;
108 } else
109 rsyserr(FERROR, errno, "backup mkdir %s failed", backup_dir_buf);
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110 *name = '\0';
111 ret = False;
9b594a53 112 goto cleanup;
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113 }
114
115 /* Try to transfer the directory settings of the actual dir
116 * that the files are coming from. */
117 if (x_stat(rel, &sx.st, NULL) < 0)
118 rsyserr(FERROR, errno, "backup stat %s failed", full_fname(rel));
119 else {
120 struct file_struct *file;
121 if (!(file = make_file(rel, NULL, NULL, 0, NO_FILTERS)))
122 continue;
1c3344a1 123#ifdef SUPPORT_ACLS
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124 if (preserve_acls && !S_ISLNK(file->mode)) {
125 get_acl(rel, &sx);
126 cache_tmp_acl(file, &sx);
127 free_acl(&sx);
128 }
1e999f9f 129#endif
16edf865 130#ifdef SUPPORT_XATTRS
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131 if (preserve_xattrs) {
132 get_xattr(rel, &sx);
133 cache_tmp_xattr(file, &sx);
134 free_xattr(&sx);
135 }
16edf865 136#endif
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137 set_file_attrs(backup_dir_buf, file, NULL, NULL, 0);
138 unmake_file(file);
139 }
140
141 *b = '/';
142 }
143
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144 cleanup:
145
cb197514 146#ifdef SUPPORT_ACLS
3696674b 147 uncache_tmp_acls();
cb197514
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148#endif
149#ifdef SUPPORT_XATTRS
3696674b 150 uncache_tmp_xattrs();
cb197514 151#endif
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152
153 return ret;
154}
155
156/* Make a complete pathname for backup file and verify any new path elements. */
157char *get_backup_name(const char *fname)
158{
159 if (backup_dir) {
160 /* copy fname into backup_dir_buf while validating the dirs. */
161 if (copy_valid_path(fname))
162 return backup_dir_buf;
0b8a9bd6 163 /* copy_valid_path() has printed an error message. */
3696674b 164 return NULL;
47d6a60c 165 }
de0e2250 166
0b8a9bd6
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167 if (stringjoin(backup_dir_buf, MAXPATHLEN, fname, backup_suffix, NULL) < MAXPATHLEN)
168 return backup_dir_buf;
169
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170 rprintf(FERROR, "backup filename too long\n");
171 return NULL;
378a074c
AT
172}
173
21cddef2
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174/* Has same return codes as make_backup(). */
175static inline int link_or_rename(const char *from, const char *to,
176 BOOL prefer_rename, STRUCT_STAT *stp)
66203a98 177{
d735fe20
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178#ifdef SUPPORT_HARD_LINKS
179 if (!prefer_rename) {
21cddef2 180#ifndef CAN_HARDLINK_SYMLINK
d735fe20
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181 if (S_ISLNK(stp->st_mode))
182 return 0; /* Use copy code. */
21cddef2 183#endif
21cddef2 184#ifndef CAN_HARDLINK_SPECIAL
d735fe20
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185 if (IS_SPECIAL(stp->st_mode) || IS_DEVICE(stp->st_mode))
186 return 0; /* Use copy code. */
21cddef2 187#endif
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188 if (do_link(from, to) == 0) {
189 if (DEBUG_GTE(BACKUP, 1))
190 rprintf(FINFO, "make_backup: HLINK %s successful.\n", from);
5e2d51ee 191 return 2;
3696674b 192 }
5e2d51ee
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193 /* We prefer to rename a regular file rather than copy it. */
194 if (!S_ISREG(stp->st_mode) || errno == EEXIST || errno == EISDIR)
d735fe20 195 return 0;
21cddef2
WD
196 }
197#endif
21cddef2
WD
198 if (do_rename(from, to) == 0) {
199 if (stp->st_nlink > 1 && !S_ISDIR(stp->st_mode)) {
200 /* If someone has hard-linked the file into the backup
201 * dir, rename() might return success but do nothing! */
5e2d51ee 202 robust_unlink(from); /* Just in case... */
f1ca7c44 203 }
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204 if (DEBUG_GTE(BACKUP, 1))
205 rprintf(FINFO, "make_backup: RENAME %s successful.\n", from);
21cddef2 206 return 1;
f1ca7c44 207 }
62c9e6b3 208 return 0;
de0e2250 209}
66203a98 210
21cddef2
WD
211/* Hard-link, rename, or copy an item to the backup name. Returns 2 if item
212 * was duplicated into backup area, 1 if item was moved, or 0 for failure.*/
213int make_backup(const char *fname, BOOL prefer_rename)
66203a98 214{
13710874 215 stat_x sx;
66203a98 216 struct file_struct *file;
21cddef2
WD
217 int save_preserve_xattrs;
218 char *buf = get_backup_name(fname);
219 int ret = 0;
220
221 if (!buf)
222 return 0;
378a074c 223
09ca0d15
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224 init_stat_x(&sx);
225 /* Return success if no file to keep. */
9439c0cb 226 if (x_lstat(fname, &sx.st, NULL) < 0)
9fd62d15 227 return 1;
66203a98 228
21cddef2
WD
229 /* Try a hard-link or a rename first. Using rename is not atomic, but
230 * is more efficient than forcing a copy for larger files when no hard-
231 * linking is possible. */
232 if ((ret = link_or_rename(fname, buf, prefer_rename, &sx.st)) != 0)
233 goto success;
d735fe20 234 if (errno == EEXIST || errno == EISDIR) {
21cddef2
WD
235 STRUCT_STAT bakst;
236 if (do_lstat(buf, &bakst) == 0) {
237 int flags = get_del_for_flag(bakst.st_mode) | DEL_FOR_BACKUP | DEL_RECURSE;
238 if (delete_item(buf, bakst.st_mode, flags) != 0)
239 return 0;
240 }
241 if ((ret = link_or_rename(fname, buf, prefer_rename, &sx.st)) != 0)
242 goto success;
82ad07c4 243 }
378a074c 244
21cddef2
WD
245 /* Fall back to making a copy. */
246 if (!(file = make_file(fname, NULL, &sx.st, 0, NO_FILTERS)))
247 return 1; /* the file could have disappeared */
248
1c3344a1
WD
249#ifdef SUPPORT_ACLS
250 if (preserve_acls && !S_ISLNK(file->mode)) {
251 get_acl(fname, &sx);
cb197514 252 cache_tmp_acl(file, &sx);
1c3344a1
WD
253 free_acl(&sx);
254 }
255#endif
16edf865
WD
256#ifdef SUPPORT_XATTRS
257 if (preserve_xattrs) {
258 get_xattr(fname, &sx);
cb197514 259 cache_tmp_xattr(file, &sx);
16edf865
WD
260 free_xattr(&sx);
261 }
262#endif
1c3344a1 263
378a074c 264 /* Check to see if this is a device file, or link */
b5c6a6ae
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265 if ((am_root && preserve_devices && IS_DEVICE(file->mode))
266 || (preserve_specials && IS_SPECIAL(file->mode))) {
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WD
267 if (do_mknod(buf, file->mode, sx.st.st_rdev) < 0)
268 rsyserr(FERROR, errno, "mknod %s failed", full_fname(buf));
269 else if (DEBUG_GTE(BACKUP, 1))
270 rprintf(FINFO, "make_backup: DEVICE %s successful.\n", fname);
21cddef2 271 ret = 2;
47d6a60c 272 }
378a074c 273
4f5b0756 274#ifdef SUPPORT_LINKS
21cddef2 275 if (!ret && preserve_links && S_ISLNK(file->mode)) {
82ad07c4 276 const char *sl = F_SYMLINK(file);
e6f3a33c 277 if (safe_symlinks && unsafe_symlink(sl, fname)) {
951e826b 278 if (INFO_GTE(SYMSAFE, 1)) {
7a3ce973
MM
279 rprintf(FINFO, "not backing up unsafe symlink \"%s\" -> \"%s\"\n",
280 fname, sl);
47d6a60c 281 }
21cddef2 282 ret = 2;
93e28fbd 283 } else {
3696674b
WD
284 if (do_symlink(sl, buf) < 0)
285 rsyserr(FERROR, errno, "link %s -> \"%s\"", full_fname(buf), sl);
286 else if (DEBUG_GTE(BACKUP, 1))
287 rprintf(FINFO, "make_backup: SYMLINK %s successful.\n", fname);
21cddef2 288 ret = 2;
47d6a60c 289 }
47d6a60c 290 }
378a074c 291#endif
378a074c 292
21cddef2 293 if (!ret && !S_ISREG(file->mode)) {
3696674b 294 rprintf(FINFO, "make_bak: skipping non-regular file %s\n", fname);
82ad07c4 295 unmake_file(file);
cb197514
WD
296#ifdef SUPPORT_ACLS
297 uncache_tmp_acls();
298#endif
299#ifdef SUPPORT_XATTRS
300 uncache_tmp_xattrs();
301#endif
21cddef2 302 return 2;
47d6a60c 303 }
66203a98 304
21cddef2
WD
305 /* Copy to backup tree if a file. */
306 if (!ret) {
3696674b 307 if (copy_file(fname, buf, -1, file->mode) < 0) {
d62bcc17 308 rsyserr(FERROR, errno, "keep_backup failed: %s -> \"%s\"",
45c49b52 309 full_fname(fname), buf);
21cddef2 310 unmake_file(file);
cb197514
WD
311#ifdef SUPPORT_ACLS
312 uncache_tmp_acls();
313#endif
314#ifdef SUPPORT_XATTRS
315 uncache_tmp_xattrs();
316#endif
21cddef2 317 return 0;
47d6a60c 318 }
3696674b
WD
319 if (DEBUG_GTE(BACKUP, 1))
320 rprintf(FINFO, "make_backup: COPY %s successful.\n", fname);
21cddef2 321 ret = 2;
47d6a60c 322 }
21cddef2
WD
323
324 save_preserve_xattrs = preserve_xattrs;
e9489cd6 325 preserve_xattrs = 0;
16edf865 326 set_file_attrs(buf, file, NULL, fname, 0);
e9489cd6 327 preserve_xattrs = save_preserve_xattrs;
21cddef2 328
82ad07c4 329 unmake_file(file);
cb197514
WD
330#ifdef SUPPORT_ACLS
331 uncache_tmp_acls();
332#endif
333#ifdef SUPPORT_XATTRS
334 uncache_tmp_xattrs();
335#endif
378a074c 336
21cddef2 337 success:
3696674b
WD
338 if (INFO_GTE(BACKUP, 1))
339 rprintf(FINFO, "backed up %s to %s\n", fname, buf);
21cddef2 340 return ret;
66203a98 341}