basic: Move userns_supported() to namespace-util.h

src/basic/namespace-util.c

@@ -644,6 +644,10 @@ int userns_enter_and_pin(int userns_fd, pid_t *ret_pid) {
         return 0;
 }
 
+bool userns_supported(void) {
+        return access("/proc/self/uid_map", F_OK) >= 0;
+}
+
 int userns_get_base_uid(int userns_fd, uid_t *ret_uid, gid_t *ret_gid) {
         _cleanup_(sigkill_waitp) pid_t pid = 0;
         int r;

src/basic/namespace-util.h

@@ -91,6 +91,7 @@ int userns_acquire_empty(void);
 int userns_acquire(const char *uid_map, const char *gid_map, bool setgroups_deny);
 int userns_acquire_self_root(void);
 int userns_enter_and_pin(int userns_fd, pid_t *ret_pid);
+bool userns_supported(void);
 
 int userns_get_base_uid(int userns_fd, uid_t *ret_uid, gid_t *ret_gid);
 

src/basic/user-util.h

@@ -106,10 +106,6 @@ int take_etc_passwd_lock(const char *root);
 #define PTR_TO_GID(p) ((gid_t) (((uintptr_t) (p))-1))
 #define GID_TO_PTR(u) ((void*) (((uintptr_t) (u))+1))
 
-static inline bool userns_supported(void) {
-        return access("/proc/self/uid_map", F_OK) >= 0;
-}
-
 typedef enum ValidUserFlags {
         VALID_USER_RELAX         = 1 << 0,
         VALID_USER_WARN          = 1 << 1,