adds newlib-nano settings

newlib-nano/read.c

@@ -0,0 +1,22 @@
+#include <stdint.h>
+#include <errno.h>
+#include <unistd.h>
+#include "stub.h"
+#include <platform.h>
+
+ssize_t _read(int fd, void* ptr, size_t len);
+
+ssize_t _read(int fd, void* ptr, size_t len) {
+  uint8_t * current = (uint8_t *)ptr;
+  ssize_t result = 0;
+  if (isatty(fd)) {
+    for (current = (uint8_t *)ptr;
+        (current < ((uint8_t *)ptr) + len) && (uart_get_rx_avail(uart) > 0);
+        current ++) {
+      *current = uart_read(uart);
+      result++;
+    }
+    return result;
+  }
+  return _stub(EBADF);
+}