We only support eventfd under POSIX, move qemu_eventfd() to os-posix.c

[qemu.git] / os-posix.c

diff --git a/os-posix.c b/os-posix.c
index 6321e990c5fcce0a7b6c9b67def844ec21b6c60d..612b6417371a60b4cd785fb7a7f5f3661141ef8c 100644 (file)
--- a/os-posix.c
+++ b/os-posix.c
@@ -43,6 +43,10 @@
 #include <sys/prctl.h>
 #endif
 
+#ifdef CONFIG_EVENTFD
+#include <sys/eventfd.h>
+#endif
+
 static struct passwd *user_pwd;
 static const char *chroot_dir;
 static int daemonize;
@@ -329,3 +333,31 @@ void os_set_line_buffering(void)
 {
     setvbuf(stdout, NULL, _IOLBF, 0);
 }
+
+/*
+ * Creates an eventfd that looks like a pipe and has EFD_CLOEXEC set.
+ */
+int qemu_eventfd(int fds[2])
+{
+#ifdef CONFIG_EVENTFD
+    int ret;
+
+    ret = eventfd(0, 0);
+    if (ret >= 0) {
+        fds[0] = ret;
+        qemu_set_cloexec(ret);
+        if ((fds[1] = dup(ret)) == -1) {
+            close(ret);
+            return -1;
+        }
+        qemu_set_cloexec(fds[1]);
+        return 0;
+    }
+
+    if (errno != ENOSYS) {
+        return -1;
+    }
+#endif
+
+    return qemu_pipe(fds);
+}