Linux: use accept4 if available (glibc 2.10)

configure.ac

@@ -583,7 +583,7 @@ AC_CHECK_FUNCS(fdatasync,,
 ])
 
 dnl Check for non-standard system calls
-AC_CHECK_FUNCS([vmsplice eventfd fstatfs])
+AC_CHECK_FUNCS([vmsplice eventfd fstatfs accept4])
 
 AH_BOTTOM([#include <vlc_fixups.h>])
 

src/network/httpd.c

@@ -2517,6 +2517,10 @@ static void* httpd_HostThread( void *data )
                 continue;
 
             /* */
+#ifdef HAVE_ACCEPT4
+            fd = accept4 (fd, NULL, NULL, SOCK_CLOEXEC);
+            if (fd == -1 && errno == ENOSYS)
+#endif
             fd = accept (fd, NULL, NULL);
             if (fd == -1)
                 continue;

src/network/tcp.c

@@ -255,8 +255,15 @@ next_ai: /* failure */
 int net_AcceptSingle (vlc_object_t *obj, int lfd)
 {
     int fd;
+
     do
+    {
+#ifdef HAVE_ACCEPT4
+        fd = accept4 (lfd, NULL, NULL, SOCK_CLOEXEC);
+        if (fd == -1 && errno == ENOSYS)
+#endif
         fd = accept (lfd, NULL, NULL);
+    }
     while (fd == -1 && errno == EINTR);
 
     if (fd == -1)