From 881bf800f35c79f778b1cdb401ad7ff780b010e9 Mon Sep 17 00:00:00 2001
From: yangchen <yangchen145@huawei.com>
Date: Wed, 6 Dec 2023 12:23:51 +0800
Subject: [PATCH] fix example print error

---
 src/lstack/api/lstack_epoll.c | 7 +------
 src/lstack/api/lstack_wrap.c  | 4 ++++
 2 files changed, 5 insertions(+), 6 deletions(-)

diff --git a/src/lstack/api/lstack_epoll.c b/src/lstack/api/lstack_epoll.c
index a2d2a9b..7825bed 100644
--- a/src/lstack/api/lstack_epoll.c
+++ b/src/lstack/api/lstack_epoll.c
@@ -941,12 +941,7 @@ static nfds_t fds_select2poll(int maxfd, fd_set *readfds, fd_set *writefds, fd_s
 
 int lstack_select(int maxfd, fd_set *readfds, fd_set *writefds, fd_set *exceptfds, struct timeval *timeval)
 {
-    if (maxfd == 0) {
-        LSTACK_LOG(ERR, LSTACK, "select maxfd is zero\n");
-        return 0;
-    }
-
-    if (maxfd < 0 || maxfd > FD_SETSIZE || (readfds == NULL && writefds == NULL && exceptfds == NULL)) {
+    if (maxfd < 0 || maxfd > FD_SETSIZE) {
         LSTACK_LOG(ERR, LSTACK, "select input param error, fd num=%d\n", maxfd);
         GAZELLE_RETURN(EINVAL);
     }
diff --git a/src/lstack/api/lstack_wrap.c b/src/lstack/api/lstack_wrap.c
index abbf8a1..69a1409 100644
--- a/src/lstack/api/lstack_wrap.c
+++ b/src/lstack/api/lstack_wrap.c
@@ -595,6 +595,10 @@ static int32_t do_sigaction(int32_t signum, const struct sigaction *act, struct
 
 static int32_t do_select(int32_t nfds, fd_set *readfds, fd_set *writefds, fd_set *exceptfds, struct timeval *timeout)
 {
+    if ((select_posix_path() == PATH_KERNEL) || !(readfds || writefds || exceptfds) || nfds == 0) {
+        return posix_api->select_fn(nfds, readfds, writefds, exceptfds, timeout);
+    }
+    
     return posix_api->select_fn(nfds, readfds, writefds, exceptfds, timeout);
 }
 
-- 
2.27.0