zte's code,first commit

Change-Id: I9a04da59e459a9bc0d67f101f700d9d7dc8d681b
diff --git a/ap/build/uClibc/libc/sysdeps/linux/common/writev.c b/ap/build/uClibc/libc/sysdeps/linux/common/writev.c
new file mode 100644
index 0000000..bd0e407
--- /dev/null
+++ b/ap/build/uClibc/libc/sysdeps/linux/common/writev.c
@@ -0,0 +1,50 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * writev() for uClibc
+ *
+ * Copyright (C) 2000-2006 Erik Andersen <andersen@uclibc.org>
+ *
+ * Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball.
+ */
+
+#include <sys/syscall.h>
+#include <sys/uio.h>
+
+#ifdef __UCLIBC_HAS_THREADS_NATIVE__
+#include <errno.h>
+#include <sysdep-cancel.h>
+
+/* We should deal with kernel which have a smaller UIO_FASTIOV as well
+   as a very big count.  */
+static ssize_t __writev (int fd, const struct iovec *vector, int count)
+{
+  ssize_t bytes_written;
+
+  bytes_written = INLINE_SYSCALL (writev, 3, fd, vector, count);
+
+  if (bytes_written >= 0 || errno != EINVAL || count <= UIO_FASTIOV)
+    return bytes_written;
+
+  /* glibc tries again, but we do not. */
+  /* return __atomic_writev_replacement (fd, vector, count); */
+
+  return -1;
+}
+
+ssize_t writev (int fd, const struct iovec *vector, int count)
+{
+  if (SINGLE_THREAD_P)
+    return __writev (fd, vector, count);
+
+  int oldtype = LIBC_CANCEL_ASYNC ();
+
+  ssize_t result = __writev (fd, vector, count);
+
+  LIBC_CANCEL_RESET (oldtype);
+
+  return result;
+}
+#else
+_syscall3(ssize_t, writev, int, filedes, const struct iovec *, vector,
+		  int, count)
+#endif