commit 27651c0c1681b0a80bd41a5ab55b9dcd7a55eb1c
author hucongcong <hucong.c@foxmail.com> Thu Nov 10 10:17:53 2016 +0800
committer hucongcong <hucong.c@foxmail.com> Thu Nov 10 10:17:53 2016 +0800
tree 2cefcb79f5ca551a9a72339bd82d02062b9fba3d
parent 600649cedbdfa068aa28bc3189d0f64ca8d5ad14

Core: slight optimization in ngx_chain_update_chains().

It is not necessary to traverse *busy and link the *out when *out is NULL.

src/core/ngx_buf.c

diff --git a/src/core/ngx_buf.c b/src/core/ngx_buf.c
index 00b6644..d30a0a4 100644
--- a/src/core/ngx_buf.c
+++ b/src/core/ngx_buf.c
@@ -186,17 +186,19 @@
 {
     ngx_chain_t  *cl;
 
-    if (*busy == NULL) {
-        *busy = *out;
+    if (*out) {
+        if (*busy == NULL) {
+            *busy = *out;
 
-    } else {
-        for (cl = *busy; cl->next; cl = cl->next) { /* void */ }
+        } else {
+            for (cl = *busy; cl->next; cl = cl->next) { /* void */ }
 
-        cl->next = *out;
+            cl->next = *out;
+        }
+
+        *out = NULL;
     }
 
-    *out = NULL;
-
     while (*busy) {
         cl = *busy;