From: Patrik Wall <patrik.wall.91@gmail.com>
Date: Thu, 30 Apr 2026 12:43:49 +0000 (+0200)
Subject: Events: support for SO_SNDBUF on outbound peer connections
X-Git-Tag: release-1.31.3~13
X-Git-Url: http://git.kaiwu.me/http/$%7BGITURL%7D/doc/static/gitweb.js?a=commitdiff_plain;h=3fe9fc45735b059ab6d3ee997e06bcc6850b36ab;p=nginx.git

Events: support for SO_SNDBUF on outbound peer connections

ngx_event_connect_peer() honors SO_RCVBUF via pc->rcvbuf but had
no equivalent for SO_SNDBUF.  This adds pc->sndbuf and the matching
setsockopt() call, mirroring the existing SO_RCVBUF path.
Both setsockopt() calls are made non-fatal.

Existing callers leaving sndbuf at 0 retain prior behavior, since
setsockopt() is only invoked when the field is non-zero.  These
fields are consumed by various proxying modules in follow-up commits.
---

diff --git a/src/event/ngx_event_connect.c b/src/event/ngx_event_connect.c
index 668084a7b..e18b3a5c6 100644
--- a/src/event/ngx_event_connect.c
+++ b/src/event/ngx_event_connect.c
@@ -65,11 +65,23 @@ ngx_event_connect_peer(ngx_peer_connection_t *pc)
 
     if (pc->rcvbuf) {
         if (setsockopt(s, SOL_SOCKET, SO_RCVBUF,
-                       (const void *) &pc->rcvbuf, sizeof(int)) == -1)
+                       (const void *) &pc->rcvbuf, sizeof(int))
+            == -1)
         {
             ngx_log_error(NGX_LOG_ALERT, pc->log, ngx_socket_errno,
-                          "setsockopt(SO_RCVBUF) failed");
-            goto failed;
+                          "setsockopt(SO_RCVBUF, %d) failed, ignored",
+                          pc->rcvbuf);
+        }
+    }
+
+    if (pc->sndbuf) {
+        if (setsockopt(s, SOL_SOCKET, SO_SNDBUF,
+                       (const void *) &pc->sndbuf, sizeof(int))
+            == -1)
+        {
+            ngx_log_error(NGX_LOG_ALERT, pc->log, ngx_socket_errno,
+                          "setsockopt(SO_SNDBUF, %d) failed, ignored",
+                          pc->sndbuf);
         }
     }
 
diff --git a/src/event/ngx_event_connect.h b/src/event/ngx_event_connect.h
index e428e7376..0604fef0f 100644
--- a/src/event/ngx_event_connect.h
+++ b/src/event/ngx_event_connect.h
@@ -57,6 +57,7 @@ struct ngx_peer_connection_s {
 
     int                              type;
     int                              rcvbuf;
+    int                              sndbuf;
 
     ngx_log_t                       *log;