-/*
- Copyright (C) Andrew Tridgell 1999
-
- This program is free software; you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2 of the License, or
- (at your option) any later version.
-
- This program is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- GNU General Public License for more details.
-
- You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
-*/
-
-/* backup handling code */
+/*
+ * Backup handling code.
+ *
+ * Copyright (C) 1999 Andrew Tridgell
+ * Copyright (C) 2003-2009 Wayne Davison
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, visit the http://fsf.org website.
+ */
#include "rsync.h"
+#include "ifuncs.h"
-extern int verbose;
+extern int am_root;
+extern int preserve_acls;
+extern int preserve_xattrs;
+extern int preserve_devices;
+extern int preserve_specials;
+extern int preserve_links;
+extern int safe_symlinks;
+extern int backup_dir_len;
+extern unsigned int backup_dir_remainder;
+extern char backup_dir_buf[MAXPATHLEN];
extern char *backup_suffix;
extern char *backup_dir;
-
-/* simple backup creates a backup with a suffix in the same directory */
-static int make_simple_backup(char *fname)
+/* Returns -1 on error, 0 on missing dir, and 1 on present dir. */
+static int validate_backup_dir(void)
{
- char fnamebak[MAXPATHLEN];
- if (strlen(fname) + strlen(backup_suffix) > (MAXPATHLEN-1)) {
- rprintf(FERROR,"backup filename too long\n");
- return 0;
- }
+ STRUCT_STAT st;
- slprintf(fnamebak,sizeof(fnamebak),"%s%s",fname,backup_suffix);
- if (do_rename(fname,fnamebak) != 0) {
- /* cygwin (at least version b19) reports EINVAL */
- if (errno != ENOENT && errno != EINVAL) {
- rprintf(FERROR,"rename %s %s : %s\n",fname,fnamebak,strerror(errno));
+ if (do_lstat(backup_dir_buf, &st) < 0) {
+ if (errno == ENOENT)
return 0;
- }
- } else if (verbose > 1) {
- rprintf(FINFO,"backed up %s to %s\n",fname,fnamebak);
+ rsyserr(FERROR, errno, "backup lstat %s failed", backup_dir_buf);
+ return -1;
+ }
+ if (!S_ISDIR(st.st_mode)) {
+ int flags = get_del_for_flag(st.st_mode) | DEL_FOR_BACKUP | DEL_RECURSE;
+ if (delete_item(backup_dir_buf, st.st_mode, flags) == 0)
+ return 0;
+ return -1;
}
return 1;
}
-
-/* recursively make a directory path */
-static int make_dir(char *name, int mask)
+/* Create a backup path from the given fname, putting the result into
+ * backup_dir_buf. Any new directories (compared to the prior backup
+ * path) are ensured to exist as directories, replacing anything else
+ * that may be in the way (e.g. a symlink). */
+static BOOL copy_valid_path(const char *fname)
{
- char newdir [MAXPATHLEN];
- char *p, *d;
-
- /* copy pathname over, look for last '/' */
- for (p = d = newdir; *name; *d++ = *name++)
- if (*name == '/')
- p = d;
- if (p == newdir)
- return 0;
- *p = 0;
+ const char *f;
+ int val;
+ BOOL ret = True;
+ stat_x sx;
+ char *b, *rel = backup_dir_buf + backup_dir_len, *name = rel;
- /* make the new directory, if that fails then make its parent */
- while (do_mkdir (newdir, mask) != 0)
- if ((errno != ENOENT) || !make_dir (newdir, mask))
- return 0;
+ for (f = fname, b = rel; *f && *f == *b; f++, b++) {
+ if (*b == '/')
+ name = b + 1;
+ }
- return 1;
-} /* make_dir */
+ if (stringjoin(rel, backup_dir_remainder, fname, backup_suffix, NULL) >= backup_dir_remainder) {
+ rprintf(FERROR, "backup filename too long\n");
+ *name = '\0';
+ return False;
+ }
+ for ( ; ; name = b + 1) {
+ if ((b = strchr(name, '/')) == NULL)
+ return True;
+ *b = '\0';
-/* robustly move a file, creating new directory structures if necessary */
-static int robust_move(char *src, char *dst)
-{
- int keep_trying = 4;
- int keep_path_extfs = 0;
- int failed;
-
- while (keep_trying) {
- if (keep_path_extfs)
- failed = copy_file (src, dst, 0755);
- else
- failed = robust_rename (src, dst);
-
- if (failed) {
- if (verbose > 2)
- rprintf (FERROR, "robust_move failed: %s(%d)\n",
- strerror (errno), errno);
- switch (errno) {
- /* external filesystem */
- case EXDEV:
- keep_path_extfs = 1;
- keep_trying--;
- break;
- /* no directory to write to */
- case ENOENT:
- make_dir (dst, 0755);
- keep_trying--;
+ val = validate_backup_dir();
+ if (val == 0)
+ break;
+ if (val < 0) {
+ *name = '\0';
+ return False;
+ }
+
+ *b = '/';
+ }
+
+ init_stat_x(&sx);
+
+ for ( ; b; name = b + 1, b = strchr(name, '/')) {
+ *b = '\0';
+
+ while (do_mkdir(backup_dir_buf, ACCESSPERMS) < 0) {
+ if (errno == EEXIST) {
+ val = validate_backup_dir();
+ if (val > 0)
break;
- default:
- keep_trying = 0;
- } /* switch */
- } else
- keep_trying = 0;
- } /* while */
- return (!failed);
-} /* robust_move */
-
-
-/* if we have a backup_dir, then we get here from make_backup().
- We will move the file to be deleted into a parallel directory tree */
-static int keep_backup(char *fname)
-{
- static int initialised;
+ if (val == 0)
+ continue;
+ } else
+ rsyserr(FERROR, errno, "backup mkdir %s failed", backup_dir_buf);
+ *name = '\0';
+ ret = False;
+ goto cleanup;
+ }
- char keep_name [MAXPATHLEN];
- STRUCT_STAT st;
- struct file_struct *file;
+ /* Try to transfer the directory settings of the actual dir
+ * that the files are coming from. */
+ if (x_stat(rel, &sx.st, NULL) < 0)
+ rsyserr(FERROR, errno, "backup stat %s failed", full_fname(rel));
+ else {
+ struct file_struct *file;
+ if (!(file = make_file(rel, NULL, NULL, 0, NO_FILTERS)))
+ continue;
+#ifdef SUPPORT_ACLS
+ if (preserve_acls && !S_ISLNK(file->mode)) {
+ get_acl(rel, &sx);
+ cache_tmp_acl(file, &sx);
+ free_acl(&sx);
+ }
+#endif
+#ifdef SUPPORT_XATTRS
+ if (preserve_xattrs) {
+ get_xattr(rel, &sx);
+ cache_tmp_xattr(file, &sx);
+ free_xattr(&sx);
+ }
+#endif
+ set_file_attrs(backup_dir_buf, file, NULL, NULL, 0);
+ unmake_file(file);
+ }
- if (!initialised) {
- if (backup_dir[strlen(backup_dir) - 1] == '/')
- backup_dir[strlen(backup_dir) - 1] = 0;
- if (verbose > 0)
- rprintf (FINFO, "backup_dir is %s\n", backup_dir);
- initialised = 1;
+ *b = '/';
}
- /* return if no file to keep */
-#if SUPPORT_LINKS
- if (do_lstat (fname, &st)) return 1;
-#else
- if (do_stat (fname, &st)) return 1;
+ cleanup:
+
+#ifdef SUPPORT_ACLS
+ uncache_tmp_acls();
+#endif
+#ifdef SUPPORT_XATTRS
+ uncache_tmp_xattrs();
#endif
- file = make_file (0, fname);
+ return ret;
+}
- /* make a complete pathname for backup file */
- if (strlen(backup_dir) + strlen(fname) > (MAXPATHLEN - 1)) {
- rprintf (FERROR, "keep_backup filename too long\n");
- return 0;
+/* Make a complete pathname for backup file and verify any new path elements. */
+char *get_backup_name(const char *fname)
+{
+ if (backup_dir) {
+ /* copy fname into backup_dir_buf while validating the dirs. */
+ if (copy_valid_path(fname))
+ return backup_dir_buf;
+ /* copy_valid_path() has printed an error message. */
+ return NULL;
}
- slprintf(keep_name, sizeof (keep_name), "%s/%s", backup_dir, fname);
-
- if (!S_ISDIR(file->mode)) {
- /* move to keep tree if a file */
- if (!robust_move (fname, keep_name))
- rprintf(FERROR, "keep_backup failed %s -> %s : %s\n",
- fname, keep_name, strerror(errno));
- } else {
- /* this bit only used to "keep" empty directories */
- /* make the parent directories */
- make_dir (keep_name, 0755);
- /* now make the (empty) directory */
- do_mkdir (keep_name, file->mode);
- if (verbose > 1)
- rprintf (FINFO, "keep_backup: made empty dir: %s\n",
- keep_name);
- }
-
- set_perms (keep_name, file, NULL, 0);
- free_file (file);
- free (file);
- if (verbose > 1)
- rprintf (FINFO, "keep_backup %s -> %s\n", fname, keep_name);
- return 1;
-} /* keep_backup */
+ if (stringjoin(backup_dir_buf, MAXPATHLEN, fname, backup_suffix, NULL) < MAXPATHLEN)
+ return backup_dir_buf;
+
+ rprintf(FERROR, "backup filename too long\n");
+ return NULL;
+}
-/* main backup switch routine */
-int make_backup(char *fname)
+/* Has same return codes as make_backup(). */
+static inline int link_or_rename(const char *from, const char *to,
+ BOOL prefer_rename, STRUCT_STAT *stp)
{
- if (backup_dir)
- return (keep_backup(fname));
- else
- return (make_simple_backup(fname));
+#ifdef SUPPORT_HARD_LINKS
+ if (!prefer_rename) {
+#ifndef CAN_HARDLINK_SYMLINK
+ if (S_ISLNK(stp->st_mode))
+ return 0; /* Use copy code. */
+#endif
+#ifndef CAN_HARDLINK_SPECIAL
+ if (IS_SPECIAL(stp->st_mode) || IS_DEVICE(stp->st_mode))
+ return 0; /* Use copy code. */
+#endif
+ if (do_link(from, to) == 0) {
+ if (DEBUG_GTE(BACKUP, 1))
+ rprintf(FINFO, "make_backup: HLINK %s successful.\n", from);
+ return 2;
+ }
+ /* We prefer to rename a regular file rather than copy it. */
+ if (!S_ISREG(stp->st_mode) || errno == EEXIST || errno == EISDIR)
+ return 0;
+ }
+#endif
+ if (do_rename(from, to) == 0) {
+ if (stp->st_nlink > 1 && !S_ISDIR(stp->st_mode)) {
+ /* If someone has hard-linked the file into the backup
+ * dir, rename() might return success but do nothing! */
+ robust_unlink(from); /* Just in case... */
+ }
+ if (DEBUG_GTE(BACKUP, 1))
+ rprintf(FINFO, "make_backup: RENAME %s successful.\n", from);
+ return 1;
+ }
+ return 0;
}
+/* Hard-link, rename, or copy an item to the backup name. Returns 2 if item
+ * was duplicated into backup area, 1 if item was moved, or 0 for failure.*/
+int make_backup(const char *fname, BOOL prefer_rename)
+{
+ stat_x sx;
+ struct file_struct *file;
+ int save_preserve_xattrs;
+ char *buf = get_backup_name(fname);
+ int ret = 0;
+
+ if (!buf)
+ return 0;
+
+ init_stat_x(&sx);
+ /* Return success if no file to keep. */
+ if (x_lstat(fname, &sx.st, NULL) < 0)
+ return 1;
+
+ /* Try a hard-link or a rename first. Using rename is not atomic, but
+ * is more efficient than forcing a copy for larger files when no hard-
+ * linking is possible. */
+ if ((ret = link_or_rename(fname, buf, prefer_rename, &sx.st)) != 0)
+ goto success;
+ if (errno == EEXIST || errno == EISDIR) {
+ STRUCT_STAT bakst;
+ if (do_lstat(buf, &bakst) == 0) {
+ int flags = get_del_for_flag(bakst.st_mode) | DEL_FOR_BACKUP | DEL_RECURSE;
+ if (delete_item(buf, bakst.st_mode, flags) != 0)
+ return 0;
+ }
+ if ((ret = link_or_rename(fname, buf, prefer_rename, &sx.st)) != 0)
+ goto success;
+ }
+
+ /* Fall back to making a copy. */
+ if (!(file = make_file(fname, NULL, &sx.st, 0, NO_FILTERS)))
+ return 1; /* the file could have disappeared */
+
+#ifdef SUPPORT_ACLS
+ if (preserve_acls && !S_ISLNK(file->mode)) {
+ get_acl(fname, &sx);
+ cache_tmp_acl(file, &sx);
+ free_acl(&sx);
+ }
+#endif
+#ifdef SUPPORT_XATTRS
+ if (preserve_xattrs) {
+ get_xattr(fname, &sx);
+ cache_tmp_xattr(file, &sx);
+ free_xattr(&sx);
+ }
+#endif
+
+ /* Check to see if this is a device file, or link */
+ if ((am_root && preserve_devices && IS_DEVICE(file->mode))
+ || (preserve_specials && IS_SPECIAL(file->mode))) {
+ if (do_mknod(buf, file->mode, sx.st.st_rdev) < 0)
+ rsyserr(FERROR, errno, "mknod %s failed", full_fname(buf));
+ else if (DEBUG_GTE(BACKUP, 1))
+ rprintf(FINFO, "make_backup: DEVICE %s successful.\n", fname);
+ ret = 2;
+ }
+
+#ifdef SUPPORT_LINKS
+ if (!ret && preserve_links && S_ISLNK(file->mode)) {
+ const char *sl = F_SYMLINK(file);
+ if (safe_symlinks && unsafe_symlink(sl, fname)) {
+ if (INFO_GTE(SYMSAFE, 1)) {
+ rprintf(FINFO, "not backing up unsafe symlink \"%s\" -> \"%s\"\n",
+ fname, sl);
+ }
+ ret = 2;
+ } else {
+ if (do_symlink(sl, buf) < 0)
+ rsyserr(FERROR, errno, "link %s -> \"%s\"", full_fname(buf), sl);
+ else if (DEBUG_GTE(BACKUP, 1))
+ rprintf(FINFO, "make_backup: SYMLINK %s successful.\n", fname);
+ ret = 2;
+ }
+ }
+#endif
+
+ if (!ret && !S_ISREG(file->mode)) {
+ rprintf(FINFO, "make_bak: skipping non-regular file %s\n", fname);
+ unmake_file(file);
+#ifdef SUPPORT_ACLS
+ uncache_tmp_acls();
+#endif
+#ifdef SUPPORT_XATTRS
+ uncache_tmp_xattrs();
+#endif
+ return 2;
+ }
+
+ /* Copy to backup tree if a file. */
+ if (!ret) {
+ if (copy_file(fname, buf, -1, file->mode) < 0) {
+ rsyserr(FERROR, errno, "keep_backup failed: %s -> \"%s\"",
+ full_fname(fname), buf);
+ unmake_file(file);
+#ifdef SUPPORT_ACLS
+ uncache_tmp_acls();
+#endif
+#ifdef SUPPORT_XATTRS
+ uncache_tmp_xattrs();
+#endif
+ return 0;
+ }
+ if (DEBUG_GTE(BACKUP, 1))
+ rprintf(FINFO, "make_backup: COPY %s successful.\n", fname);
+ ret = 2;
+ }
+
+ save_preserve_xattrs = preserve_xattrs;
+ preserve_xattrs = 0;
+ set_file_attrs(buf, file, NULL, fname, 0);
+ preserve_xattrs = save_preserve_xattrs;
+
+ unmake_file(file);
+#ifdef SUPPORT_ACLS
+ uncache_tmp_acls();
+#endif
+#ifdef SUPPORT_XATTRS
+ uncache_tmp_xattrs();
+#endif
+
+ success:
+ if (INFO_GTE(BACKUP, 1))
+ rprintf(FINFO, "backed up %s to %s\n", fname, buf);
+ return ret;
+}