native: add random peripheral implementation

boards/native/Makefile.features

@@ -1 +1,2 @@
 FEATURES_PROVIDED += transceiver periph_cpuid cpp
+FEATURES_PROVIDED += periph_random

cpu/native/include/periph_conf.h

@@ -0,0 +1,35 @@
+/**
+ * Native CPU peripheral configuration
+ *
+ * Copyright (C) 2014 Ludwig Ortmann <ludwig.ortmann@fu-berlin.de>
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser
+ * General Public License v2.1. See the file LICENSE in the top level
+ * directory for more details.
+ *
+ * @ingroup native_cpu
+ * @{
+ * @file
+ * @author  Ludwig Ortmann <ludwig.ortmann@fu-berlin.de>
+ */
+
+#ifndef PERIPH_CONF_H
+#define PERIPH_CONF_H
+
+#ifdef __cplusplus
+ extern "C" {
+#endif
+
+/**
+ * @name Random Number Generator configuration
+ * @{
+ */
+#define RANDOM_NUMOF        (1U)
+/** @} */
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* PERIPH_CONF_H */
+/** @} */

cpu/native/periph/random.c

@@ -0,0 +1,72 @@
+/*
+ * Copyright (C) 2014 Ludwig Ortmann <ludwig.ortmann@fu-berlin.de>
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser
+ * General Public License v2.1. See the file LICENSE in the top level
+ * directory for more details.
+ */
+
+/**
+ * @ingroup     native_cpu
+ * @{
+ *
+ * @author      Ludwig Ortmann <ludwig.ortmann@fu-berlin.de>
+ */
+
+#include <string.h>
+#include <stdlib.h>
+#include <err.h>
+
+#include "cpu-conf.h"
+#include "native_internal.h"
+
+#include "periph/random.h"
+
+#define ENABLE_DEBUG (0)
+#include "debug.h"
+
+static int powered = 0;
+
+void random_init(void)
+{
+    DEBUGF("random_init: powering on\n");
+    random_poweron();
+}
+
+int random_read(char *buf, unsigned int num)
+{
+    if (!powered) {
+        warnx("random_read: random device not powered, failing\n");
+        return 0;
+    }
+
+    DEBUGF("random_read: writing %ui bytes\n", num);
+    for (unsigned i = 0; i < num; i++) {
+        _native_syscall_enter();
+        buf[i] = (char)real_random();
+        _native_syscall_leave();
+    }
+    return num;
+}
+
+/**
+ * seed host random module with @ref _native_id
+ */
+void random_poweron(void)
+{
+    DEBUGF("random_poweron: power on\n");
+    powered = 1;
+    _native_syscall_enter();
+    real_srandom((unsigned int)_native_id);
+    _native_syscall_leave();
+}
+
+void random_poweroff(void)
+{
+    DEBUGF("random_poweroff: power off\n");
+    powered = 0;
+}
+
+/**
+ * @}
+ */