xen_disk: use bdrv_aio_flush instead of bdrv_flush

[qemu.git] / compatfd.c

diff --git a/compatfd.c b/compatfd.c
index 41586ceaea969e1eef23c17ec8214a3aa5a3f8ff..42f81cafe49e83abbf2f4ea6991f5d519bd855de 100644 (file)
--- a/compatfd.c
+++ b/compatfd.c
@@ -9,6 +9,8 @@
  * This work is licensed under the terms of the GNU GPL, version 2.  See
  * the COPYING file in the top-level directory.
  *
+ * Contributions after 2012-01-13 are licensed under the terms of the
+ * GNU GPL, version 2 or (at your option) any later version.
  */
 
 #include "qemu-common.h"
@@ -115,3 +117,22 @@ int qemu_signalfd(const sigset_t *mask)
 
     return qemu_signalfd_compat(mask);
 }
+
+bool qemu_signalfd_available(void)
+{
+#ifdef CONFIG_SIGNALFD
+    sigset_t mask;
+    int fd;
+    bool ok;
+    sigemptyset(&mask);
+    errno = 0;
+    fd = syscall(SYS_signalfd, -1, &mask, _NSIG / 8);
+    ok = (errno != ENOSYS);
+    if (fd >= 0) {
+        close(fd);
+    }
+    return ok;
+#else
+    return false;
+#endif
+}