+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+ This file is part of systemd.
+
+ Copyright 2015 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include "util.h"
+#include "path-util.h"
+#include "rm-rf.h"
+
+int rm_rf_children(int fd, RemoveFlags flags, struct stat *root_dev) {
+ _cleanup_closedir_ DIR *d = NULL;
+ int ret = 0, r;
+
+ assert(fd >= 0);
+
+ /* This returns the first error we run into, but nevertheless
+ * tries to go on. This closes the passed fd. */
+
+ if (!(flags & REMOVE_PHYSICAL)) {
+
+ r = fd_is_temporary_fs(fd);
+ if (r < 0) {
+ safe_close(fd);
+ return r;
+ }
+
+ if (!r) {
+ /* We refuse to clean physical file systems
+ * with this call, unless explicitly
+ * requested. This is extra paranoia just to
+ * be sure we never ever remove non-state
+ * data */
+
+ log_error("Attempted to remove disk file system, and we can't allow that.");
+ safe_close(fd);
+ return -EPERM;
+ }
+ }
+
+ d = fdopendir(fd);
+ if (!d) {
+ safe_close(fd);
+ return errno == ENOENT ? 0 : -errno;
+ }
+
+ for (;;) {
+ struct dirent *de;
+ bool is_dir;
+ struct stat st;
+
+ errno = 0;
+ de = readdir(d);
+ if (!de) {
+ if (errno != 0 && ret == 0)
+ ret = -errno;
+ return ret;
+ }
+
+ if (streq(de->d_name, ".") || streq(de->d_name, ".."))
+ continue;
+
+ if (de->d_type == DT_UNKNOWN || (de->d_type == DT_DIR && root_dev)) {
+ if (fstatat(fd, de->d_name, &st, AT_SYMLINK_NOFOLLOW) < 0) {
+ if (ret == 0 && errno != ENOENT)
+ ret = -errno;
+ continue;
+ }
+
+ is_dir = S_ISDIR(st.st_mode);
+ } else
+ is_dir = de->d_type == DT_DIR;
+
+ if (is_dir) {
+ int subdir_fd;
+
+ /* if root_dev is set, remove subdirectories only, if device is same as dir */
+ if (root_dev && st.st_dev != root_dev->st_dev)
+ continue;
+
+ subdir_fd = openat(fd, de->d_name, O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC|O_NOFOLLOW|O_NOATIME);
+ if (subdir_fd < 0) {
+ if (ret == 0 && errno != ENOENT)
+ ret = -errno;
+ continue;
+ }
+
+ /* We pass REMOVE_PHYSICAL here, to avoid
+ * doing the fstatfs() to check the file
+ * system type again for each directory */
+ r = rm_rf_children(subdir_fd, flags | REMOVE_PHYSICAL, root_dev);
+ if (r < 0 && ret == 0)
+ ret = r;
+
+ if (unlinkat(fd, de->d_name, AT_REMOVEDIR) < 0) {
+ if (ret == 0 && errno != ENOENT)
+ ret = -errno;
+ }
+
+ } else if (!(flags & REMOVE_ONLY_DIRECTORIES)) {
+
+ if (unlinkat(fd, de->d_name, 0) < 0) {
+ if (ret == 0 && errno != ENOENT)
+ ret = -errno;
+ }
+ }
+ }
+}
+
+int rm_rf(const char *path, RemoveFlags flags) {
+ int fd, r;
+ struct statfs s;
+
+ assert(path);
+
+ /* We refuse to clean the root file system with this
+ * call. This is extra paranoia to never cause a really
+ * seriously broken system. */
+ if (path_equal(path, "/")) {
+ log_error("Attempted to remove entire root file system, and we can't allow that.");
+ return -EPERM;
+ }
+
+ fd = open(path, O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC|O_NOFOLLOW|O_NOATIME);
+ if (fd < 0) {
+
+ if (errno != ENOTDIR && errno != ELOOP)
+ return -errno;
+
+ if (!(flags & REMOVE_PHYSICAL)) {
+ if (statfs(path, &s) < 0)
+ return -errno;
+
+ if (!is_temporary_fs(&s)) {
+ log_error("Attempted to remove disk file system, and we can't allow that.");
+ return -EPERM;
+ }
+ }
+
+ if ((flags & REMOVE_ROOT) && !(flags & REMOVE_ONLY_DIRECTORIES))
+ if (unlink(path) < 0 && errno != ENOENT)
+ return -errno;
+
+ return 0;
+ }
+
+ r = rm_rf_children(fd, flags, NULL);
+
+ if (flags & REMOVE_ROOT) {
+
+ if (rmdir(path) < 0 && errno != ENOENT) {
+ if (r == 0)
+ r = -errno;
+ }
+ }
+
+ return r;
+}
~ianmdlvl / elogind.git / commitdiff