Add BSP and semihosting library for nios2-generic-nommu QEMU emulation.

libgloss/nios2/io-close.c

@@ -0,0 +1,43 @@
+/*
+ * io-close.c -- 
+ *
+ * Copyright (c) 2006 CodeSourcery Inc
+ * Copyright (c) 2018 Mentor Graphics
+ *
+ * The authors hereby grant permission to use, copy, modify, distribute,
+ * and license this software and its documentation for any purpose, provided
+ * that existing copyright notices are retained in all copies and that this
+ * notice is included verbatim in any distributions. No written agreement,
+ * license, or royalty fee is required for any of the authorized uses.
+ * Modifications to this software may be copyrighted by their authors
+ * and need not follow the licensing terms described here, provided that
+ * the new terms are clearly indicated on the first page of each file where
+ * they apply.
+ */
+
+#include <unistd.h>
+#include <errno.h>
+#define IO close
+#include "io.h"
+
+/*
+ * close -- close a file descriptor.
+ * input parameters:
+ *   0 : file descriptor
+ * output parameters:
+ *   0 : result
+ *   1 : errno
+ */
+
+int close (int fd)
+{
+#if HOSTED
+  gdb_parambuf_t parameters;
+  parameters[0] = (uint32_t) fd;
+  __io_hosted (HOSTED_CLOSE, parameters);
+  errno = __hosted_from_gdb_errno (parameters[1]);
+  return parameters[0];
+#else
+  return 0;
+#endif
+}