* Backup handling code.
*
* Copyright (C) 1999 Andrew Tridgell
- * Copyright (C) 2003-2009 Wayne Davison
+ * Copyright (C) 2003-2022 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
extern char *backup_suffix;
extern char *backup_dir;
-/* make a complete pathname for backup file */
-char *get_backup_name(const char *fname)
+/* Returns -1 on error, 0 on missing dir, and 1 on present dir. */
+static int validate_backup_dir(void)
{
- if (backup_dir) {
- if (stringjoin(backup_dir_buf + backup_dir_len, backup_dir_remainder,
- fname, backup_suffix, NULL) < backup_dir_remainder)
- return backup_dir_buf;
- } else {
- if (stringjoin(backup_dir_buf, MAXPATHLEN,
- fname, backup_suffix, NULL) < MAXPATHLEN)
- return backup_dir_buf;
- }
+ STRUCT_STAT st;
- rprintf(FERROR, "backup filename too long\n");
- return NULL;
+ if (do_lstat(backup_dir_buf, &st) < 0) {
+ if (errno == ENOENT)
+ return 0;
+ 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;
}
-/****************************************************************************
-Create a directory given an absolute path, perms based upon another directory
-path
-****************************************************************************/
-int make_bak_dir(const char *fullpath)
+/* 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 fbuf[MAXPATHLEN], *rel, *end, *p;
- struct file_struct *file;
- int len = backup_dir_len;
+ const char *f;
+ int val;
+ BOOL ret = True;
stat_x sx;
+ char *b, *rel = backup_dir_buf + backup_dir_len, *name = rel;
- while (*fullpath == '.' && fullpath[1] == '/') {
- fullpath += 2;
- len -= 2;
+ for (f = fname, b = rel; *f && *f == *b; f++, b++) {
+ if (*b == '/')
+ name = b + 1;
}
- if (strlcpy(fbuf, fullpath, sizeof fbuf) >= sizeof fbuf)
- return -1;
+ if (stringjoin(rel, backup_dir_remainder, fname, backup_suffix, NULL) >= backup_dir_remainder) {
+ rprintf(FERROR, "backup filename too long\n");
+ *name = '\0';
+ return False;
+ }
- rel = fbuf + len;
- end = p = rel + strlen(rel);
-
- /* Try to find an existing dir, starting from the deepest dir. */
- while (1) {
- if (--p == fbuf)
- return -1;
- if (*p == '/') {
- *p = '\0';
- if (mkdir_defmode(fbuf) == 0)
- break;
- if (errno != ENOENT) {
- rsyserr(FERROR, errno,
- "make_bak_dir mkdir %s failed",
- full_fname(fbuf));
- return -1;
- }
+ for ( ; ; name = b + 1) {
+ if ((b = strchr(name, '/')) == NULL)
+ return True;
+ *b = '\0';
+
+ val = validate_backup_dir();
+ if (val == 0)
+ break;
+ if (val < 0) {
+ *name = '\0';
+ return False;
}
+
+ *b = '/';
}
- /* Make all the dirs that we didn't find on the way here. */
- while (1) {
- if (p >= rel) {
- /* Try to transfer the directory settings of the
- * actual dir that the files are coming from. */
- init_stat_x(&sx);
- if (x_stat(rel, &sx.st, NULL) < 0) {
- rsyserr(FERROR, errno,
- "make_bak_dir stat %s failed",
- full_fname(rel));
- } else {
- if (!(file = make_file(rel, NULL, NULL, 0, NO_FILTERS)))
+ 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;
+ if (val == 0)
continue;
+ } else
+ rsyserr(FERROR, errno, "backup mkdir %s failed", backup_dir_buf);
+ *name = '\0';
+ ret = False;
+ goto cleanup;
+ }
+
+ /* 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);
- }
+ 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);
- }
+ if (preserve_xattrs) {
+ get_xattr(rel, &sx);
+ cache_tmp_xattr(file, &sx);
+ free_xattr(&sx);
+ }
#endif
- set_file_attrs(fbuf, file, NULL, NULL, 0);
- unmake_file(file);
+ set_file_attrs(backup_dir_buf, file, NULL, NULL, 0);
+ unmake_file(file);
+ }
+
+ *b = '/';
+ }
+
+ cleanup:
+
#ifdef SUPPORT_ACLS
- uncache_tmp_acls();
+ uncache_tmp_acls();
#endif
#ifdef SUPPORT_XATTRS
- uncache_tmp_xattrs();
+ uncache_tmp_xattrs();
#endif
- }
- }
- *p = '/';
- p += strlen(p);
- if (p == end)
- break;
- if (mkdir_defmode(fbuf) < 0) {
- rsyserr(FERROR, errno, "make_bak_dir mkdir %s failed",
- full_fname(fbuf));
- return -1;
+
+ return ret;
+}
+
+/* Make a complete pathname for backup file and verify any new path elements. */
+char *get_backup_name(const char *fname)
+{
+ if (backup_dir) {
+ static int initialized = 0;
+ if (!initialized) {
+ int ret;
+ if (backup_dir_len > 1)
+ backup_dir_buf[backup_dir_len-1] = '\0';
+ ret = make_path(backup_dir_buf, 0);
+ if (backup_dir_len > 1)
+ backup_dir_buf[backup_dir_len-1] = '/';
+ if (ret < 0)
+ return NULL;
+ initialized = 1;
}
+ /* 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;
}
- return 0;
+ if (stringjoin(backup_dir_buf, MAXPATHLEN, fname, backup_suffix, NULL) < MAXPATHLEN)
+ return backup_dir_buf;
+
+ rprintf(FERROR, "backup filename too long\n");
+ return NULL;
}
/* 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 (S_ISLNK(stp->st_mode)) {
- if (prefer_rename)
- goto do_rename;
+#ifdef SUPPORT_HARD_LINKS
+ if (!prefer_rename) {
#ifndef CAN_HARDLINK_SYMLINK
- return 0; /* Use copy code. */
+ if (S_ISLNK(stp->st_mode))
+ return 0; /* Use copy code. */
#endif
- }
- if (IS_SPECIAL(stp->st_mode) || IS_DEVICE(stp->st_mode)) {
- if (prefer_rename)
- goto do_rename;
#ifndef CAN_HARDLINK_SPECIAL
- return 0; /* Use copy code. */
+ if (IS_SPECIAL(stp->st_mode) || IS_DEVICE(stp->st_mode))
+ return 0; /* Use copy code. */
#endif
- }
-#ifdef SUPPORT_HARD_LINKS
- if (!S_ISDIR(stp->st_mode)) {
- if (do_link(from, to) == 0)
+ if (do_link(from, to) == 0) {
+ if (DEBUG_GTE(BACKUP, 1))
+ rprintf(FINFO, "make_backup: HLINK %s successful.\n", from);
return 2;
- return 0;
+ }
+ /* We prefer to rename a regular file rather than copy it. */
+ if (!S_ISREG(stp->st_mode) || errno == EEXIST || errno == EISDIR)
+ return 0;
}
#endif
- do_rename:
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(to); /* Just in case... */
+ 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.*/
+/* Hard-link, rename, or copy an item to the backup name. Returns 0 for
+ * failure, 1 if item was moved, 2 if item was duplicated or hard linked
+ * into backup area, or 3 if item doesn't exist or isn't a regular file. */
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);
+ char *buf;
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;
+ return 3;
+
+ if (!(buf = get_backup_name(fname)))
+ return 0;
/* 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) {
+ 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 ((ret = link_or_rename(fname, buf, prefer_rename, &sx.st)) != 0)
goto success;
- } else if (backup_dir && errno == ENOENT) {
- /* If the backup dir is missing, try again after making it. */
- if (make_bak_dir(buf) != 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 */
+ return 3; /* the file could have disappeared */
#ifdef SUPPORT_ACLS
if (preserve_acls && !S_ISLNK(file->mode)) {
/* 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))) {
- int save_errno;
- if (do_mknod(buf, file->mode, sx.st.st_rdev) < 0) {
- save_errno = errno ? errno : EINVAL; /* 0 paranoia */
- if (errno == ENOENT && make_bak_dir(buf) == 0) {
- if (do_mknod(buf, file->mode, sx.st.st_rdev) < 0)
- save_errno = errno ? errno : save_errno;
- else
- save_errno = 0;
- }
- if (save_errno) {
- rsyserr(FERROR, save_errno, "mknod %s failed",
- full_fname(buf));
- }
- } else
- save_errno = 0;
- if (DEBUG_GTE(BACKUP, 1) && save_errno == 0) {
- rprintf(FINFO, "make_backup: DEVICE %s successful.\n",
- fname);
- }
- ret = 2;
- }
-
- if (!ret && S_ISDIR(file->mode)) {
- int ret_code;
- /* make an empty directory */
- if (do_mkdir(buf, file->mode) < 0) {
- int save_errno = errno ? errno : EINVAL; /* 0 paranoia */
- if (errno == ENOENT && make_bak_dir(buf) == 0) {
- if (do_mkdir(buf, file->mode) < 0)
- save_errno = errno ? errno : save_errno;
- else
- save_errno = 0;
- }
- if (save_errno) {
- rsyserr(FINFO, save_errno, "mkdir %s failed",
- full_fname(buf));
- }
- }
-
- ret_code = do_rmdir(fname);
- if (DEBUG_GTE(BACKUP, 1)) {
- rprintf(FINFO, "make_backup: RMDIR %s returns %i\n",
- full_fname(fname), ret_code);
- }
+ 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;
}
const char *sl = F_SYMLINK(file);
if (safe_symlinks && unsafe_symlink(sl, fname)) {
if (INFO_GTE(SYMSAFE, 1)) {
- rprintf(FINFO, "ignoring unsafe symlink %s -> %s\n",
- full_fname(buf), sl);
+ rprintf(FINFO, "not backing up unsafe symlink \"%s\" -> \"%s\"\n",
+ fname, sl);
}
ret = 2;
} else {
- if (do_symlink(sl, buf) < 0) {
- int save_errno = errno ? errno : EINVAL; /* 0 paranoia */
- if (errno == ENOENT && make_bak_dir(buf) == 0) {
- if (do_symlink(sl, buf) < 0)
- save_errno = errno ? errno : save_errno;
- else
- save_errno = 0;
- }
- if (save_errno) {
- rsyserr(FERROR, save_errno, "link %s -> \"%s\"",
- full_fname(buf), sl);
- }
- }
+ 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);
+ if (INFO_GTE(NONREG, 1))
+ rprintf(FINFO, "make_bak: skipping non-regular file %s\n", fname);
unmake_file(file);
#ifdef SUPPORT_ACLS
uncache_tmp_acls();
#ifdef SUPPORT_XATTRS
uncache_tmp_xattrs();
#endif
- return 2;
+ return 3;
}
/* Copy to backup tree if a file. */
if (!ret) {
- if (copy_file(fname, buf, -1, file->mode, 1) < 0) {
+ if (copy_file(fname, buf, -1, file->mode) < 0) {
rsyserr(FERROR, errno, "keep_backup failed: %s -> \"%s\"",
full_fname(fname), buf);
unmake_file(file);
#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);
+ set_file_attrs(buf, file, NULL, fname, ATTRS_ACCURATE_TIME);
preserve_xattrs = save_preserve_xattrs;
unmake_file(file);
#endif
success:
- if (INFO_GTE(BACKUP, 1)) {
- rprintf(FINFO, "backed up %s to %s\n",
- fname, buf);
- }
+ if (INFO_GTE(BACKUP, 1))
+ rprintf(FINFO, "backed up %s to %s\n", fname, buf);
return ret;
}