MHD_start_daemon(): allow MHD_USE_POLL only with MHD_USE_THREAD_PER_CONNECTION for backward compatibility.

New applications are advised to use MHD_USE_INTERNAL_POLLING_THREAD with MHD_USE_THREAD_PER_CONNECTION.

ChangeLog

@@ -1,3 +1,7 @@
+Tue Apr 25 19:11:00 CEST 2017
+	Allow flag MHD_USE_POLL with MHD_USE_THREAD_PER_CONNECTION and without
+	flag MHD_USE_INTERNAL_POLLING_THREAD for backward compatibility. -EG
+
 Mon Apr 24 17:29:45 CEST 2017
 	Enforce RFC 7230's rule on no whitespace by default,
 	introduce new MHD_USE_PERMISSIVE_CHECKS to disable. -CG

src/microhttpd/daemon.c

@@ -5366,7 +5366,8 @@ MHD_start_daemon_va (unsigned int flags,
   /* Check for invalid combinations of flags. */
   if ( ((0 != (*pflags & MHD_USE_POLL)) && (0 != (*pflags & MHD_USE_EPOLL))) ||
        ((0 != (*pflags & MHD_USE_EPOLL)) && (0 != (*pflags & MHD_USE_THREAD_PER_CONNECTION))) ||
-       ((0 != (*pflags & MHD_USE_POLL)) && (0 == (*pflags & MHD_USE_INTERNAL_POLLING_THREAD))) ||
+       ((0 != (*pflags & MHD_USE_POLL)) &&
+           (0 == (*pflags & (MHD_USE_INTERNAL_POLLING_THREAD | MHD_USE_THREAD_PER_CONNECTION)))) ||
        ((0 != (*pflags & MHD_USE_AUTO)) && (0 != (*pflags & (MHD_USE_POLL | MHD_USE_EPOLL)))) )
     return NULL;