util-lib: split our string related calls from util.[ch] into its own file string-util.[ch]

There are more than enough calls doing string manipulations to deserve
its own files, hence do something about it.

This patch also sorts the #include blocks of all files that needed to be
updated, according to the sorting suggestions from CODING_STYLE. Since
pretty much every file needs our string manipulation functions this
effectively means that most files have sorted #include blocks now.

Also touches a few unrelated include files.

29 files changed, 174 insertions, 144 deletions

diff --git a/src/udev/ata_id/ata_id.c b/src/udev/ata_id/ata_id.c
index 1d1798dd10..7acd7b4e92 100644
--- a/src/udev/ata_id/ata_id.c
+++ b/src/udev/ata_id/ata_id.c
@@ -19,28 +19,29 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#include <stdio.h>
-#include <stdlib.h>
-#include <stdint.h>
-#include <unistd.h>
-#include <fcntl.h>
 #include <ctype.h>
-#include <string.h>
 #include <errno.h>
+#include <fcntl.h>
 #include <getopt.h>
+#include <linux/bsg.h>
+#include <linux/hdreg.h>
 #include <scsi/scsi.h>
-#include <scsi/sg.h>
 #include <scsi/scsi_ioctl.h>
+#include <scsi/sg.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
 #include <sys/ioctl.h>
-#include <sys/types.h>
 #include <sys/stat.h>
-#include <linux/hdreg.h>
-#include <linux/bsg.h>
+#include <sys/types.h>
+#include <unistd.h>
 
 #include "libudev.h"
+
 #include "libudev-private.h"
-#include "udev-util.h"
 #include "log.h"
+#include "udev-util.h"
 
 #define COMMAND_TIMEOUT_MSEC (30 * 1000)
 
diff --git a/src/udev/cdrom_id/cdrom_id.c b/src/udev/cdrom_id/cdrom_id.c
index 001bae7a24..72f284f710 100644
--- a/src/udev/cdrom_id/cdrom_id.c
+++ b/src/udev/cdrom_id/cdrom_id.c
@@ -17,24 +17,25 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#include <stdio.h>
-#include <stddef.h>
-#include <stdlib.h>
-#include <unistd.h>
-#include <string.h>
-#include <limits.h>
-#include <fcntl.h>
 #include <errno.h>
+#include <fcntl.h>
 #include <getopt.h>
-#include <time.h>
+#include <limits.h>
+#include <linux/cdrom.h>
 #include <scsi/sg.h>
-#include <sys/types.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/ioctl.h>
 #include <sys/stat.h>
 #include <sys/time.h>
-#include <sys/ioctl.h>
-#include <linux/cdrom.h>
+#include <sys/types.h>
+#include <time.h>
+#include <unistd.h>
 
 #include "libudev.h"
+
 #include "libudev-private.h"
 #include "random-util.h"
 
diff --git a/src/udev/collect/collect.c b/src/udev/collect/collect.c
index b3a1f0bca1..b234792e23 100644
--- a/src/udev/collect/collect.c
+++ b/src/udev/collect/collect.c
@@ -19,13 +19,14 @@
  *
  */
 
-#include <stdio.h>
-#include <stddef.h>
 #include <errno.h>
 #include <getopt.h>
+#include <stddef.h>
+#include <stdio.h>
 
 #include "libudev-private.h"
 #include "macro.h"
+#include "string-util.h"
 
 #define BUFSIZE 16
 #define UDEV_ALARM_TIMEOUT 180
diff --git a/src/udev/net/link-config.c b/src/udev/net/link-config.c
index 4b8c5053a4..c308f898ea 100644
--- a/src/udev/net/link-config.c
+++ b/src/udev/net/link-config.c
@@ -22,22 +22,22 @@
 #include <netinet/ether.h>
 #include <linux/netdevice.h>
 
+#include "sd-netlink.h"
 
-#include "missing.h"
-#include "link-config.h"
+#include "conf-files.h"
+#include "conf-parser.h"
 #include "ethtool-util.h"
-
 #include "libudev-private.h"
-#include "sd-netlink.h"
-#include "util.h"
+#include "link-config.h"
 #include "log.h"
-#include "strv.h"
-#include "path-util.h"
-#include "conf-parser.h"
-#include "conf-files.h"
+#include "missing.h"
 #include "netlink-util.h"
 #include "network-internal.h"
+#include "path-util.h"
 #include "random-util.h"
+#include "string-util.h"
+#include "strv.h"
+#include "util.h"
 
 struct link_config_ctx {
         LIST_HEAD(link_config, links);
diff --git a/src/udev/net/link-config.h b/src/udev/net/link-config.h
index c52db2ce55..4fcbee8b92 100644
--- a/src/udev/net/link-config.h
+++ b/src/udev/net/link-config.h
@@ -21,10 +21,11 @@
 
 #pragma once
 
-#include "ethtool-util.h"
+#include "libudev.h"
+
 #include "condition.h"
+#include "ethtool-util.h"
 #include "list.h"
-#include "libudev.h"
 
 typedef struct link_config_ctx link_config_ctx;
 typedef struct link_config link_config;
diff --git a/src/udev/scsi_id/scsi_id.c b/src/udev/scsi_id/scsi_id.c
index adb91869df..cbf9478e72 100644
--- a/src/udev/scsi_id/scsi_id.c
+++ b/src/udev/scsi_id/scsi_id.c
@@ -16,22 +16,24 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#include <stdio.h>
-#include <stdlib.h>
+#include <ctype.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <getopt.h>
+#include <signal.h>
 #include <stdarg.h>
 #include <stdbool.h>
-#include <unistd.h>
-#include <signal.h>
-#include <fcntl.h>
-#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
 #include <string.h>
-#include <ctype.h>
-#include <getopt.h>
 #include <sys/stat.h>
+#include <unistd.h>
 
 #include "libudev.h"
+
 #include "libudev-private.h"
 #include "scsi_id.h"
+#include "string-util.h"
 #include "udev-util.h"
 
 static const struct option options[] = {
diff --git a/src/udev/scsi_id/scsi_serial.c b/src/udev/scsi_id/scsi_serial.c
index de3b4f7581..c7ef783684 100644
--- a/src/udev/scsi_id/scsi_serial.c
+++ b/src/udev/scsi_id/scsi_serial.c
@@ -17,27 +17,29 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#include <sys/types.h>
-#include <sys/ioctl.h>
-#include <sys/stat.h>
-#include <stdio.h>
 #include <errno.h>
-#include <string.h>
 #include <fcntl.h>
-#include <stdlib.h>
-#include <unistd.h>
-#include <time.h>
 #include <inttypes.h>
+#include <linux/bsg.h>
+#include <linux/types.h>
 #include <scsi/scsi.h>
 #include <scsi/sg.h>
-#include <linux/types.h>
-#include <linux/bsg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/ioctl.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <time.h>
+#include <unistd.h>
 
 #include "libudev.h"
+
 #include "libudev-private.h"
+#include "random-util.h"
 #include "scsi.h"
 #include "scsi_id.h"
-#include "random-util.h"
+#include "string-util.h"
 
 /*
  * A priority based list of id, naa, and binary/ascii for the identifier
diff --git a/src/udev/udev-builtin-blkid.c b/src/udev/udev-builtin-blkid.c
index b8066ea6e9..004ddb023f 100644
--- a/src/udev/udev-builtin-blkid.c
+++ b/src/udev/udev-builtin-blkid.c
@@ -18,18 +18,20 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
+#include <blkid/blkid.h>
 #include <errno.h>
 #include <fcntl.h>
 #include <getopt.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
 #include <sys/stat.h>
-#include <blkid/blkid.h>
 
 #include "sd-id128.h"
-#include "gpt.h"
+
 #include "efivars.h"
+#include "gpt.h"
+#include "string-util.h"
 #include "udev.h"
 
 static void print_property(struct udev_device *dev, bool test, const char *name, const char *value) {
diff --git a/src/udev/udev-builtin-btrfs.c b/src/udev/udev-builtin-btrfs.c
index 3352821567..ce1a0c3882 100644
--- a/src/udev/udev-builtin-btrfs.c
+++ b/src/udev/udev-builtin-btrfs.c
@@ -17,8 +17,8 @@
   along with systemd; If not, see <http://www.gnu.org/licenses/>.
 ***/
 
-#include <stdlib.h>
 #include <fcntl.h>
+#include <stdlib.h>
 #include <sys/ioctl.h>
 
 #ifdef HAVE_LINUX_BTRFS_H
@@ -26,6 +26,7 @@
 #endif
 
 #include "missing.h"
+#include "string-util.h"
 #include "udev.h"
 
 static int builtin_btrfs(struct udev_device *dev, int argc, char *argv[], bool test) {
diff --git a/src/udev/udev-builtin-hwdb.c b/src/udev/udev-builtin-hwdb.c
index 72109d93d2..97a5a9c77f 100644
--- a/src/udev/udev-builtin-hwdb.c
+++ b/src/udev/udev-builtin-hwdb.c
@@ -17,16 +17,17 @@
   along with systemd; If not, see <http://www.gnu.org/licenses/>.
 ***/
 
-#include <stdio.h>
-#include <stdlib.h>
 #include <fnmatch.h>
 #include <getopt.h>
+#include <stdio.h>
+#include <stdlib.h>
 
-#include "udev.h"
 #include "sd-hwdb.h"
 
 #include "hwdb-util.h"
+#include "string-util.h"
 #include "udev-util.h"
+#include "udev.h"
 
 static sd_hwdb *hwdb;
 
diff --git a/src/udev/udev-builtin-input_id.c b/src/udev/udev-builtin-input_id.c
index e3fa4bc162..f36f719a94 100644
--- a/src/udev/udev-builtin-input_id.c
+++ b/src/udev/udev-builtin-input_id.c
@@ -21,15 +21,16 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include <errno.h>
+#include <stdarg.h>
 #include <stdio.h>
 #include <stdlib.h>
-#include <stdarg.h>
-#include <unistd.h>
 #include <string.h>
-#include <errno.h>
+#include <unistd.h>
 #include <linux/limits.h>
 #include <linux/input.h>
 
+#include "string-util.h"
 #include "udev.h"
 #include "util.h"
 
diff --git a/src/udev/udev-builtin-keyboard.c b/src/udev/udev-builtin-keyboard.c
index d63a8e2760..ce534ae0f9 100644
--- a/src/udev/udev-builtin-keyboard.c
+++ b/src/udev/udev-builtin-keyboard.c
@@ -18,11 +18,12 @@
 ***/
 
 #include <stdio.h>
-#include <string.h>
 #include <stdlib.h>
+#include <string.h>
 #include <sys/ioctl.h>
 #include <linux/input.h>
 
+#include "string-util.h"
 #include "udev.h"
 
 static const struct key *keyboard_lookup_key(const char *str, unsigned len);
diff --git a/src/udev/udev-builtin-kmod.c b/src/udev/udev-builtin-kmod.c
index 81e78a8aa3..9665f678fd 100644
--- a/src/udev/udev-builtin-kmod.c
+++ b/src/udev/udev-builtin-kmod.c
@@ -18,12 +18,13 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#include <stdio.h>
-#include <stdlib.h>
-#include <stdarg.h>
 #include <errno.h>
 #include <libkmod.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
 
+#include "string-util.h"
 #include "udev.h"
 
 static struct kmod_ctx *ctx = NULL;
diff --git a/src/udev/udev-builtin-net_id.c b/src/udev/udev-builtin-net_id.c
index 589f1f7822..bb721d6f0d 100644
--- a/src/udev/udev-builtin-net_id.c
+++ b/src/udev/udev-builtin-net_id.c
@@ -87,19 +87,20 @@
  *   ID_NET_NAME_PATH=enp0s29u1u2
  */
 
-#include <stdio.h>
-#include <stdlib.h>
-#include <stdarg.h>
-#include <unistd.h>
-#include <fcntl.h>
-#include <string.h>
 #include <errno.h>
+#include <fcntl.h>
 #include <net/if.h>
 #include <net/if_arp.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
 #include <linux/pci_regs.h>
 
-#include "udev.h"
 #include "fileio.h"
+#include "string-util.h"
+#include "udev.h"
 
 enum netname_type{
         NET_UNDEF,
diff --git a/src/udev/udev-builtin-path_id.c b/src/udev/udev-builtin-path_id.c
index 01e2c659ae..2c40988c7a 100644
--- a/src/udev/udev-builtin-path_id.c
+++ b/src/udev/udev-builtin-path_id.c
@@ -19,17 +19,18 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#include <stdio.h>
-#include <stdlib.h>
-#include <stdarg.h>
-#include <unistd.h>
-#include <string.h>
 #include <ctype.h>
-#include <fcntl.h>
-#include <errno.h>
 #include <dirent.h>
+#include <errno.h>
+#include <fcntl.h>
 #include <getopt.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
 
+#include "string-util.h"
 #include "udev.h"
 
 _printf_(2,3)
diff --git a/src/udev/udev-builtin-usb_id.c b/src/udev/udev-builtin-usb_id.c
index d309dc31cb..c7d47891a7 100644
--- a/src/udev/udev-builtin-usb_id.c
+++ b/src/udev/udev-builtin-usb_id.c
@@ -20,15 +20,16 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include <ctype.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <stdarg.h>
 #include <stdio.h>
 #include <stdlib.h>
-#include <stdarg.h>
-#include <unistd.h>
 #include <string.h>
-#include <ctype.h>
-#include <fcntl.h>
-#include <errno.h>
+#include <unistd.h>
 
+#include "string-util.h"
 #include "udev.h"
 
 static void set_usb_iftype(char *to, int if_class_num, size_t len) {
diff --git a/src/udev/udev-builtin.c b/src/udev/udev-builtin.c
index 4f625251d6..e6b36f124f 100644
--- a/src/udev/udev-builtin.c
+++ b/src/udev/udev-builtin.c
@@ -17,10 +17,11 @@
   along with systemd; If not, see <http://www.gnu.org/licenses/>.
 ***/
 
+#include <getopt.h>
 #include <stdio.h>
 #include <string.h>
-#include <getopt.h>
 
+#include "string-util.h"
 #include "udev.h"
 
 static bool initialized;
diff --git a/src/udev/udev-event.c b/src/udev/udev-event.c
index 1e34cbc2f5..49a45811a6 100644
--- a/src/udev/udev-event.c
+++ b/src/udev/udev-event.c
@@ -15,26 +15,27 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#include <stdlib.h>
-#include <stdio.h>
-#include <stddef.h>
-#include <unistd.h>
-#include <fcntl.h>
-#include <errno.h>
 #include <ctype.h>
-#include <string.h>
+#include <errno.h>
+#include <fcntl.h>
 #include <net/if.h>
-#include <sys/prctl.h>
 #include <poll.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
 #include <sys/epoll.h>
-#include <sys/wait.h>
+#include <sys/prctl.h>
 #include <sys/signalfd.h>
+#include <sys/wait.h>
+#include <unistd.h>
 
-#include "netlink-util.h"
 #include "event-util.h"
 #include "formats-util.h"
+#include "netlink-util.h"
 #include "process-util.h"
 #include "signal-util.h"
+#include "string-util.h"
 #include "udev.h"
 
 typedef struct Spawn {
diff --git a/src/udev/udev-node.c b/src/udev/udev-node.c
index e730fb45f1..4ed6416ecd 100644
--- a/src/udev/udev-node.c
+++ b/src/udev/udev-node.c
@@ -15,20 +15,21 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#include <string.h>
-#include <stdio.h>
-#include <stddef.h>
-#include <stdbool.h>
-#include <fcntl.h>
-#include <unistd.h>
-#include <errno.h>
 #include <dirent.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <string.h>
 #include <sys/stat.h>
+#include <unistd.h>
 
-#include "udev.h"
-#include "smack-util.h"
-#include "selinux-util.h"
 #include "formats-util.h"
+#include "selinux-util.h"
+#include "smack-util.h"
+#include "string-util.h"
+#include "udev.h"
 
 static int node_symlink(struct udev_device *dev, const char *node, const char *slink) {
         struct stat stats;
diff --git a/src/udev/udev-rules.c b/src/udev/udev-rules.c
index 62db0016eb..c8abac7fef 100644
--- a/src/udev/udev-rules.c
+++ b/src/udev/udev-rules.c
@@ -33,10 +33,11 @@
 #include "escape.h"
 #include "path-util.h"
 #include "strbuf.h"
+#include "string-util.h"
 #include "strv.h"
 #include "sysctl-util.h"
-#include "util.h"
 #include "udev.h"
+#include "util.h"
 
 #define PREALLOC_TOKEN          2048
 
diff --git a/src/udev/udev.h b/src/udev/udev.h
index d17fc8c1ea..1f9c8120c0 100644
--- a/src/udev/udev.h
+++ b/src/udev/udev.h
@@ -18,16 +18,17 @@
 
 #pragma once
 
-#include <sys/types.h>
 #include <sys/param.h>
+#include <sys/types.h>
 
-#include "macro.h"
-#include "sd-netlink.h"
 #include "libudev.h"
-#include "libudev-private.h"
-#include "util.h"
+#include "sd-netlink.h"
+
 #include "label.h"
+#include "libudev-private.h"
+#include "macro.h"
 #include "strv.h"
+#include "util.h"
 
 struct udev_event {
         struct udev *udev;
diff --git a/src/udev/udevadm-hwdb.c b/src/udev/udevadm-hwdb.c
index 00609e31b5..f9509ad640 100644
--- a/src/udev/udevadm-hwdb.c
+++ b/src/udev/udevadm-hwdb.c
@@ -17,18 +17,18 @@
   along with systemd; If not, see <http://www.gnu.org/licenses/>.
 ***/
 
-#include <stdlib.h>
+#include <ctype.h>
 #include <getopt.h>
+#include <stdlib.h>
 #include <string.h>
-#include <ctype.h>
 
-#include "util.h"
-#include "strbuf.h"
 #include "conf-files.h"
-
-#include "udev.h"
 #include "hwdb-internal.h"
 #include "hwdb-util.h"
+#include "strbuf.h"
+#include "string-util.h"
+#include "udev.h"
+#include "util.h"
 
 /*
  * Generic udev properties, key/value database based on modalias strings.
diff --git a/src/udev/udevadm-info.c b/src/udev/udevadm-info.c
index b3d5565c48..911818eb00 100644
--- a/src/udev/udevadm-info.c
+++ b/src/udev/udevadm-info.c
@@ -15,19 +15,20 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#include <string.h>
-#include <stdio.h>
-#include <stddef.h>
 #include <ctype.h>
-#include <unistd.h>
 #include <dirent.h>
 #include <errno.h>
-#include <getopt.h>
 #include <fcntl.h>
+#include <getopt.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <string.h>
 #include <sys/stat.h>
+#include <unistd.h>
 
-#include "udev.h"
+#include "string-util.h"
 #include "udev-util.h"
+#include "udev.h"
 #include "udevadm-util.h"
 
 static bool skip_attribute(const char *name) {
diff --git a/src/udev/udevadm-test-builtin.c b/src/udev/udevadm-test-builtin.c
index 35a7349439..0b180d03eb 100644
--- a/src/udev/udevadm-test-builtin.c
+++ b/src/udev/udevadm-test-builtin.c
@@ -15,12 +15,13 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#include <stdlib.h>
-#include <stddef.h>
-#include <stdio.h>
 #include <errno.h>
 #include <getopt.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
 
+#include "string-util.h"
 #include "udev.h"
 
 static void help(struct udev *udev) {
diff --git a/src/udev/udevadm-test.c b/src/udev/udevadm-test.c
index d04e618d0d..ff427cf292 100644
--- a/src/udev/udevadm-test.c
+++ b/src/udev/udevadm-test.c
@@ -16,17 +16,18 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#include <stdlib.h>
-#include <stdio.h>
-#include <stddef.h>
-#include <unistd.h>
 #include <errno.h>
-#include <signal.h>
 #include <getopt.h>
+#include <signal.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
 #include <sys/signalfd.h>
+#include <unistd.h>
 
-#include "udev.h"
+#include "string-util.h"
 #include "udev-util.h"
+#include "udev.h"
 
 static void help(void) {
 
diff --git a/src/udev/udevadm-trigger.c b/src/udev/udevadm-trigger.c
index 7af9665f8a..9d52345d92 100644
--- a/src/udev/udevadm-trigger.c
+++ b/src/udev/udevadm-trigger.c
@@ -15,16 +15,17 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include <errno.h>
+#include <fcntl.h>
+#include <getopt.h>
 #include <stddef.h>
-#include <string.h>
 #include <stdio.h>
+#include <string.h>
 #include <unistd.h>
-#include <getopt.h>
-#include <errno.h>
-#include <fcntl.h>
 
-#include "udev.h"
+#include "string-util.h"
 #include "udev-util.h"
+#include "udev.h"
 #include "udevadm-util.h"
 #include "util.h"
 
diff --git a/src/udev/udevadm-util.c b/src/udev/udevadm-util.c
index 3f0e45e26c..3539c1d6ab 100644
--- a/src/udev/udevadm-util.c
+++ b/src/udev/udevadm-util.c
@@ -15,6 +15,7 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include "string-util.h"
 #include "udevadm-util.h"
 
 struct udev_device *find_device(struct udev *udev,
diff --git a/src/udev/udevadm.c b/src/udev/udevadm.c
index b86d8921f3..60f122ebda 100644
--- a/src/udev/udevadm.c
+++ b/src/udev/udevadm.c
@@ -16,12 +16,13 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#include <stdio.h>
-#include <stddef.h>
 #include <errno.h>
 #include <getopt.h>
+#include <stddef.h>
+#include <stdio.h>
 
 #include "selinux-util.h"
+#include "string-util.h"
 #include "udev.h"
 
 static int adm_version(struct udev *udev, int argc, char *argv[]) {
diff --git a/src/udev/udevd.c b/src/udev/udevd.c
index e4d2f47745..a3f0298ae7 100644
--- a/src/udev/udevd.c
+++ b/src/udev/udevd.c
@@ -54,6 +54,7 @@
 #include "process-util.h"
 #include "selinux-util.h"
 #include "signal-util.h"
+#include "string-util.h"
 #include "terminal-util.h"
 #include "udev-util.h"
 #include "udev.h"