Add a precheck before the actual call to fcntl (#8360)

Don't bother to call fcntl if the flags are not gonna be changed.
2021-01-19 17:36:21 +08:00 · 2021-01-19 17:36:21 +08:00 · 5198b513d3
commit 5198b513d3
parent 366a16ff05
1 changed files with 5 additions and 0 deletions
--- a/src/anet.c
+++ b/src/anet.c
@ -69,6 +69,11 @@ int anetSetBlock(char *err, int fd, int non_block) {
        return ANET_ERR;
    }

+    /* Check if this flag has been set or unset, if so, 
+     * then there is no need to call fcntl to set/unset it again. */
+    if (!!(flags & O_NONBLOCK) == !!non_block)
+        return ANET_OK;
+
    if (non_block)
        flags |= O_NONBLOCK;
    else