sysusers: look at login.defs when setting the default range to allocate users

Also, even if login.defs are not present, don't start allocating at 1, but at
SYSTEM_UID_MIN.

Fixes #9769.

The test is adjusted. Actually, it was busted before, because sysusers would
never use SYSTEM_GID_MIN, so if SYSTEM_GID_MIN was different than
SYSTEM_UID_MIN, the tests would fail. On all "normal" systems the two are
equal, so we didn't notice. Since sysusers now always uses the minimum of the
two, we only need to substitute one value.

test/test-sysusers/test-10.expected-group

@@ -1,2 +1,2 @@
 u1:x:300:u2
-u2:x:SYSTEM_UID_MAX:
+u2:x:SYSTEM_UGID_MAX:

test/test-sysusers/test-10.expected-passwd

@@ -1,2 +1,2 @@
 u1:x:300:300::/:NOLOGIN
-u2:x:SYSTEM_UID_MAX:SYSTEM_UID_MAX::/:NOLOGIN
+u2:x:SYSTEM_UGID_MAX:SYSTEM_UGID_MAX::/:NOLOGIN

test/test-sysusers/test-13.expected-group

@@ -1,5 +1,5 @@
 hoge:x:300:
 baz:x:302:
-yyy:x:SYSTEM_GID_MAX:
+yyy:x:SYSTEM_UGID_MAX:
 foo:x:301:
 ccc:x:305:

test/test-sysusers/test-13.expected-passwd

@@ -2,4 +2,4 @@ foo:x:301:301::/:NOLOGIN
 aaa:x:303:302::/:NOLOGIN
 bbb:x:304:302::/:NOLOGIN
 ccc:x:305:305::/:NOLOGIN
-zzz:x:306:SYSTEM_GID_MAX::/:NOLOGIN
+zzz:x:306:SYSTEM_UGID_MAX::/:NOLOGIN

test/test-sysusers/test-14.expected-passwd

@@ -1 +1 @@
-aaa:x:SYSTEM_UID_MAX:987::/:NOLOGIN
+aaa:x:SYSTEM_UGID_MAX:987::/:NOLOGIN

test/test-sysusers/test-2.expected-group

@@ -1,4 +1,4 @@
-u1:x:SYSTEM_UID_MAX:
+u1:x:SYSTEM_UGID_MAX:
 u2:x:777:
 u3:x:778:
 u4:x:779:

test/test-sysusers/test-2.expected-passwd

@@ -1,4 +1,4 @@
-u1:x:SYSTEM_UID_MAX:SYSTEM_UID_MAX:some gecos:/random/dir:NOLOGIN
+u1:x:SYSTEM_UGID_MAX:SYSTEM_UGID_MAX:some gecos:/random/dir:NOLOGIN
 u2:x:777:777:some gecos:/random/dir:/bin/zsh
 u3:x:778:778::/random/dir2:/bin/bash
 u4:x:779:779::/:/bin/csh

test/test-sysusers/test-2.input

@@ -1,4 +1,4 @@
-# Test generation of ID dynamically based on SYSTEM_UID_MAX and
+# Test generation of ID dynamically based on SYSTEM_UGID_MAX and
 # replacement of all fields up to the login shell.
 #
 #Type Name ID  GECOS        homedir      shell

test/test-sysusers/test-6.expected-group

@@ -1,2 +1,2 @@
 g1:x:111:
-u1:x:SYSTEM_UID_MAX:
+u1:x:SYSTEM_UGID_MAX:

test/test-sysusers/test-6.expected-passwd

@@ -1 +1 @@
-u1:x:SYSTEM_UID_MAX:SYSTEM_UID_MAX::/:NOLOGIN
+u1:x:SYSTEM_UGID_MAX:SYSTEM_UGID_MAX::/:NOLOGIN

test/test-sysusers/test-8.expected-passwd

@@ -1 +1 @@
-username:x:SYSTEM_UID_MAX:300::/:NOLOGIN
+username:x:SYSTEM_UGID_MAX:300::/:NOLOGIN

test/test-sysusers/test-9.expected-passwd

@@ -1,2 +1,2 @@
 user1:x:300:300::/:NOLOGIN
-user2:x:SYSTEM_UID_MAX:300::/:NOLOGIN
+user2:x:SYSTEM_UGID_MAX:300::/:NOLOGIN