From ee5ae134dd1c0037a36b2e0c78cd4e326d002c3a Mon Sep 17 00:00:00 2001
From: akr <akr@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>
Date: Mon, 31 Oct 2011 21:01:18 +0000
Subject: [PATCH] * ext/socket/socket.c (rsock_socketpair): use SOCK_CLOEXEC if
   available.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@33593 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
---
 ChangeLog           |  5 +++++
 ext/socket/socket.c | 31 ++++++++++++++++++++++++++-----
 2 files changed, 31 insertions(+), 5 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index b6828bbc84..80fae2c9ff 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Tue Nov  1 05:59:41 2011  Tanaka Akira  <akr@fsij.org>
+
+	* ext/socket/socket.c (rsock_socketpair): use SOCK_CLOEXEC if
+	  available.
+
 Tue Nov  1 02:56:17 2011  NAKAMURA Usaku  <usa@ruby-lang.org>
 
 	* ruby.c (load_file_internal): convert the encoding of load path if
diff --git a/ext/socket/socket.c b/ext/socket/socket.c
index 31346a0295..aa1749bb4a 100644
--- a/ext/socket/socket.c
+++ b/ext/socket/socket.c
@@ -78,14 +78,35 @@ pair_yield(VALUE pair)
 #if defined HAVE_SOCKETPAIR
 
 static int
-rsock_socketpair(int domain, int type, int protocol, int sv[2])
+rsock_socketpair(int domain, int type0, int protocol, int sv[2])
 {
-    int ret;
+    int ret, type;
+
+#ifdef SOCK_CLOEXEC
+    static int try_sock_cloexec = 1;
+    if (try_sock_cloexec)
+        type = type0|SOCK_CLOEXEC;
+    else
+        type = type0;
+  retry_without_sock_cloexec:;
+#else
+    type = type0;
+#endif
 
     ret = socketpair(domain, type, protocol, sv);
-    if (ret < 0 && (errno == EMFILE || errno == ENFILE)) {
-        rb_gc();
-        ret = socketpair(domain, type, protocol, sv);
+    if (ret < 0) {
+#ifdef SOCK_CLOEXEC
+        /* SOCK_CLOEXEC is available since Linux 2.6.27.  Linux 2.6.18 fails with EINVAL */
+        if (try_sock_cloexec && errno == EINVAL) {
+            try_sock_cloexec = 0;
+            type = type0;
+            goto retry_without_sock_cloexec;
+        }
+#endif
+        if (errno == EMFILE || errno == ENFILE) {
+            rb_gc();
+            ret = socketpair(domain, type, protocol, sv);
+        }
     }
 
     return ret;