Merge pull request #19555 from poettering/nspawn-bind-user

nspawn: add --bind-user= feature for binding  host user+homedir into a container

src/shared/user-record.c

@@ -1552,7 +1552,7 @@ int user_group_record_mangle(
         if (FLAGS_SET(load_flags, USER_RECORD_REQUIRE_REGULAR) && !FLAGS_SET(m, USER_RECORD_REGULAR))
                 return json_log(v, json_flags, SYNTHETIC_ERRNO(EBADMSG), "Record lacks basic identity fields, which are required.");
 
-        if (m == 0)
+        if (!FLAGS_SET(load_flags, USER_RECORD_EMPTY_OK) && m == 0)
                 return json_log(v, json_flags, SYNTHETIC_ERRNO(EBADMSG), "Record is empty.");
 
         if (w)

src/shared/user-record.h

@@ -169,6 +169,9 @@ typedef enum UserRecordLoadFlags {
 
         /* Whether to ignore errors and load what we can */
         USER_RECORD_PERMISSIVE          = 1U << 29,
+
+        /* Whether an empty record is OK */
+        USER_RECORD_EMPTY_OK            = 1U << 30,
 } UserRecordLoadFlags;
 
 static inline UserRecordLoadFlags USER_RECORD_REQUIRE(UserRecordMask m) {