add posix 2008 limit.h

include/libc/libc_limits.h

@@ -0,0 +1,24 @@
+/*
+ * Copyright (c) 2006-2018, RT-Thread Development Team
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/*
+ * File      : libc_limits.h
+ *
+ * Change Logs:
+ * Date                 Author             Notes
+ * 2020-09-05     Meco Manthe  first version
+ */
+
+#ifndef __LIBC_LIMITS_H__
+#define __LIBC_LIMITS_H__
+
+#include <limits.h>
+
+#ifndef SSIZE_MAX
+# define SSIZE_MAX      LONG_MAX
+#endif
+
+#endif

include/rtlibc.h

@@ -20,6 +20,7 @@
 #include "libc/libc_dirent.h"
 #include "libc/libc_signal.h"
 #include "libc/libc_fdset.h"
+#include "libc/libc_limits.h"
 
 #if defined(__CC_ARM) || defined(__CLANG_ARM) || defined(__IAR_SYSTEMS_ICC__)
 typedef signed long off_t;