[newlib-cygwin/cygwin-3_5-branch] Cygwin: getgrent/getpwent: avoid local enumeration on DCs

[Corinna Vinschen <corinna@sourceware.org>]

https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=69aba646123cef13a6aa9dbec175f1e22357df2e

commit 69aba646123cef13a6aa9dbec175f1e22357df2e
Author:     Corinna Vinschen <corinna@vinschen.de>
AuthorDate: Tue Feb 20 23:54:25 2024 +0100
Commit:     Corinna Vinschen <corinna@vinschen.de>
CommitDate: Mon Feb 26 10:04:32 2024 +0100

    Cygwin: getgrent/getpwent: avoid local enumeration on DCs
    
    ...if we're supposed to enumerate the AD accounts anyway.  This
    avoids some useless duplication.
    
    Signed-off-by: Corinna Vinschen <corinna@vinschen.de>

Diff:
---
 winsup/cygwin/passwd.cc | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/winsup/cygwin/passwd.cc b/winsup/cygwin/passwd.cc
index 0be8aa6b8b0e..b8457a46f963 100644
--- a/winsup/cygwin/passwd.cc
+++ b/winsup/cygwin/passwd.cc
@@ -385,6 +385,11 @@ pg_ent::getent (void)
     case from_local:
       if (from_db
 	  && nss_db_enum_local ()
+	  /* Domain controller?  If so, sam and ad are one and the same
+	     and "local ad" would list all domain accounts twice without
+	     this test. */
+	  && (cygheap->dom.account_flat_name ()[0] != L'@'
+	      || !nss_db_enum_primary ())
 	  && (entry = enumerate_local ()))
 	return entry;
       state = from_sam;