| 1 | /* |
| 2 | Copyright (C) Andrew Tridgell 1999 |
| 3 | |
| 4 | This program is free software; you can redistribute it and/or modify |
| 5 | it under the terms of the GNU General Public License as published by |
| 6 | the Free Software Foundation; either version 2 of the License, or |
| 7 | (at your option) any later version. |
| 8 | |
| 9 | This program is distributed in the hope that it will be useful, |
| 10 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 12 | GNU General Public License for more details. |
| 13 | |
| 14 | You should have received a copy of the GNU General Public License |
| 15 | along with this program; if not, write to the Free Software |
| 16 | Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
| 17 | */ |
| 18 | |
| 19 | /* backup handling code */ |
| 20 | |
| 21 | #include "rsync.h" |
| 22 | |
| 23 | extern int verbose; |
| 24 | extern int backup_suffix_len; |
| 25 | extern int backup_dir_len; |
| 26 | extern unsigned int backup_dir_remainder; |
| 27 | extern char backup_dir_buf[MAXPATHLEN]; |
| 28 | extern char *backup_suffix; |
| 29 | extern char *backup_dir; |
| 30 | |
| 31 | extern int am_root; |
| 32 | extern int preserve_devices; |
| 33 | extern int preserve_links; |
| 34 | extern int preserve_hard_links; |
| 35 | extern int orig_umask; |
| 36 | extern int safe_symlinks; |
| 37 | |
| 38 | /* make a complete pathname for backup file */ |
| 39 | char *get_backup_name(char *fname) |
| 40 | { |
| 41 | if (backup_dir) { |
| 42 | if (stringjoin(backup_dir_buf + backup_dir_len, backup_dir_remainder, |
| 43 | fname, backup_suffix, NULL) < backup_dir_remainder) |
| 44 | return backup_dir_buf; |
| 45 | } else { |
| 46 | if (stringjoin(backup_dir_buf, MAXPATHLEN, |
| 47 | fname, backup_suffix, NULL) < MAXPATHLEN) |
| 48 | return backup_dir_buf; |
| 49 | } |
| 50 | |
| 51 | rprintf(FERROR, "backup filename too long\n"); |
| 52 | return NULL; |
| 53 | } |
| 54 | |
| 55 | /* simple backup creates a backup with a suffix in the same directory */ |
| 56 | static int make_simple_backup(char *fname) |
| 57 | { |
| 58 | char *fnamebak = get_backup_name(fname); |
| 59 | |
| 60 | if (!fnamebak) |
| 61 | return 0; |
| 62 | |
| 63 | if (do_rename(fname, fnamebak) != 0) { |
| 64 | /* cygwin (at least version b19) reports EINVAL */ |
| 65 | if (errno != ENOENT && errno != EINVAL) { |
| 66 | rsyserr(FERROR, errno, |
| 67 | "rename %s to backup %s", |
| 68 | safe_fname(fname), safe_fname(fnamebak)); |
| 69 | return 0; |
| 70 | } |
| 71 | } else if (verbose > 1) { |
| 72 | rprintf(FINFO, "backed up %s to %s\n", |
| 73 | safe_fname(fname), safe_fname(fnamebak)); |
| 74 | } |
| 75 | return 1; |
| 76 | } |
| 77 | |
| 78 | |
| 79 | /**************************************************************************** |
| 80 | Create a directory given an absolute path, perms based upon another directory |
| 81 | path |
| 82 | ****************************************************************************/ |
| 83 | static int make_bak_dir(char *fullpath) |
| 84 | { |
| 85 | STRUCT_STAT st; |
| 86 | char *rel = fullpath + backup_dir_len; |
| 87 | char *end = rel + strlen(rel); |
| 88 | char *p = end; |
| 89 | |
| 90 | while (strncmp(fullpath, "./", 2) == 0) |
| 91 | fullpath += 2; |
| 92 | |
| 93 | /* Try to find an existing dir, starting from the deepest dir. */ |
| 94 | while (1) { |
| 95 | if (--p == fullpath) { |
| 96 | p += strlen(p); |
| 97 | goto failure; |
| 98 | } |
| 99 | if (*p == '/') { |
| 100 | *p = '\0'; |
| 101 | if (do_mkdir(fullpath, 0777 & ~orig_umask) == 0) |
| 102 | break; |
| 103 | if (errno != ENOENT) { |
| 104 | rsyserr(FERROR, errno, |
| 105 | "make_bak_dir mkdir %s failed", |
| 106 | full_fname(fullpath)); |
| 107 | goto failure; |
| 108 | } |
| 109 | } |
| 110 | } |
| 111 | |
| 112 | /* Make all the dirs that we didn't find on the way here. */ |
| 113 | while (1) { |
| 114 | if (p >= rel) { |
| 115 | /* Try to transfer the directory settings of the |
| 116 | * actual dir that the files are coming from. */ |
| 117 | if (do_stat(rel, &st) < 0) { |
| 118 | rsyserr(FERROR, errno, |
| 119 | "make_bak_dir stat %s failed", |
| 120 | full_fname(rel)); |
| 121 | } else { |
| 122 | do_lchown(fullpath, st.st_uid, st.st_gid); |
| 123 | do_chmod(fullpath, st.st_mode); |
| 124 | } |
| 125 | } |
| 126 | *p = '/'; |
| 127 | p += strlen(p); |
| 128 | if (p == end) |
| 129 | break; |
| 130 | if (do_mkdir(fullpath, 0777 & ~orig_umask) < 0) { |
| 131 | rsyserr(FERROR, errno, "make_bak_dir mkdir %s failed", |
| 132 | full_fname(fullpath)); |
| 133 | goto failure; |
| 134 | } |
| 135 | } |
| 136 | return 0; |
| 137 | |
| 138 | failure: |
| 139 | while (p != end) { |
| 140 | *p = '/'; |
| 141 | p += strlen(p); |
| 142 | } |
| 143 | return -1; |
| 144 | } |
| 145 | |
| 146 | /* robustly move a file, creating new directory structures if necessary */ |
| 147 | static int robust_move(char *src, char *dst) |
| 148 | { |
| 149 | if (robust_rename(src, dst, 0755) < 0 && (errno != ENOENT |
| 150 | || make_bak_dir(dst) < 0 || robust_rename(src, dst, 0755) < 0)) |
| 151 | return -1; |
| 152 | return 0; |
| 153 | } |
| 154 | |
| 155 | |
| 156 | /* If we have a --backup-dir, then we get here from make_backup(). |
| 157 | * We will move the file to be deleted into a parallel directory tree. */ |
| 158 | static int keep_backup(char *fname) |
| 159 | { |
| 160 | STRUCT_STAT st; |
| 161 | struct file_struct *file; |
| 162 | char *buf; |
| 163 | int kept = 0; |
| 164 | int ret_code; |
| 165 | |
| 166 | /* return if no file to keep */ |
| 167 | if (do_lstat(fname, &st) < 0) |
| 168 | return 1; |
| 169 | |
| 170 | if (!(file = make_file(fname, NULL, NO_FILTERS))) |
| 171 | return 1; /* the file could have disappeared */ |
| 172 | |
| 173 | if (!(buf = get_backup_name(fname))) |
| 174 | return 0; |
| 175 | |
| 176 | /* Check to see if this is a device file, or link */ |
| 177 | if (IS_DEVICE(file->mode)) { |
| 178 | if (am_root && preserve_devices) { |
| 179 | if (do_mknod(buf, file->mode, file->u.rdev) < 0 |
| 180 | && (errno != ENOENT || make_bak_dir(buf) < 0 |
| 181 | || do_mknod(buf, file->mode, file->u.rdev) < 0)) { |
| 182 | rsyserr(FERROR, errno, "mknod %s failed", |
| 183 | full_fname(buf)); |
| 184 | } else if (verbose > 2) { |
| 185 | rprintf(FINFO, |
| 186 | "make_backup: DEVICE %s successful.\n", |
| 187 | safe_fname(fname)); |
| 188 | } |
| 189 | } |
| 190 | kept = 1; |
| 191 | do_unlink(fname); |
| 192 | } |
| 193 | |
| 194 | if (!kept && S_ISDIR(file->mode)) { |
| 195 | /* make an empty directory */ |
| 196 | if (do_mkdir(buf, file->mode) < 0 |
| 197 | && (errno != ENOENT || make_bak_dir(buf) < 0 |
| 198 | || do_mkdir(buf, file->mode) < 0)) { |
| 199 | rsyserr(FINFO, errno, "mkdir %s failed", |
| 200 | full_fname(buf)); |
| 201 | } |
| 202 | |
| 203 | ret_code = do_rmdir(fname); |
| 204 | if (verbose > 2) { |
| 205 | rprintf(FINFO, "make_backup: RMDIR %s returns %i\n", |
| 206 | full_fname(fname), ret_code); |
| 207 | } |
| 208 | kept = 1; |
| 209 | } |
| 210 | |
| 211 | #ifdef SUPPORT_LINKS |
| 212 | if (!kept && preserve_links && S_ISLNK(file->mode)) { |
| 213 | if (safe_symlinks && unsafe_symlink(file->u.link, buf)) { |
| 214 | if (verbose) { |
| 215 | rprintf(FINFO, "ignoring unsafe symlink %s -> %s\n", |
| 216 | full_fname(buf), file->u.link); |
| 217 | } |
| 218 | kept = 1; |
| 219 | } |
| 220 | if (do_symlink(file->u.link, buf) < 0 |
| 221 | && (errno != ENOENT || make_bak_dir(buf) < 0 |
| 222 | || do_symlink(file->u.link, buf) < 0)) { |
| 223 | rsyserr(FERROR, errno, "link %s -> \"%s\"", |
| 224 | full_fname(buf), safe_fname(file->u.link)); |
| 225 | } |
| 226 | do_unlink(fname); |
| 227 | kept = 1; |
| 228 | } |
| 229 | #endif |
| 230 | |
| 231 | if (!kept && !S_ISREG(file->mode)) { |
| 232 | rprintf(FINFO, "make_bak: skipping non-regular file %s\n", |
| 233 | safe_fname(fname)); |
| 234 | return 1; |
| 235 | } |
| 236 | |
| 237 | /* move to keep tree if a file */ |
| 238 | if (!kept) { |
| 239 | if (robust_move(fname, buf) != 0) { |
| 240 | rsyserr(FERROR, errno, "keep_backup failed: %s -> \"%s\"", |
| 241 | full_fname(fname), safe_fname(buf)); |
| 242 | } else if (st.st_nlink > 1) { |
| 243 | /* If someone has hard-linked the file into the backup |
| 244 | * dir, rename() might return success but do nothing! */ |
| 245 | robust_unlink(fname); /* Just in case... */ |
| 246 | } |
| 247 | } |
| 248 | set_perms(buf, file, NULL, 0); |
| 249 | free(file); |
| 250 | |
| 251 | if (verbose > 1) { |
| 252 | rprintf(FINFO, "backed up %s to %s\n", |
| 253 | safe_fname(fname), safe_fname(buf)); |
| 254 | } |
| 255 | return 1; |
| 256 | } |
| 257 | |
| 258 | |
| 259 | /* main backup switch routine */ |
| 260 | int make_backup(char *fname) |
| 261 | { |
| 262 | if (backup_dir) |
| 263 | return keep_backup(fname); |
| 264 | return make_simple_backup(fname); |
| 265 | } |