getentropy: Add test.

Update #3239.

testsuites/libtests/Makefile.am

@@ -54,6 +54,7 @@ _SUBDIRS += newlib01
 _SUBDIRS += putenvtest
 _SUBDIRS += pwdgrp01
 _SUBDIRS += pwdgrp02
+_SUBDIRS += getentropy01
 _SUBDIRS += rbheap01
 _SUBDIRS += rtmonuse
 _SUBDIRS += sha

testsuites/libtests/configure.ac

@@ -155,6 +155,7 @@ newlib01/Makefile
 putenvtest/Makefile
 pwdgrp01/Makefile
 pwdgrp02/Makefile
+getentropy01/Makefile
 rbheap01/Makefile
 rtmonuse/Makefile
 sha/Makefile

testsuites/libtests/getentropy01/Makefile.am

@@ -0,0 +1,19 @@
+rtems_tests_PROGRAMS = getentropy01
+getentropy01_SOURCES = init.c
+
+dist_rtems_tests_DATA = getentropy01.scn getentropy01.doc
+
+include $(RTEMS_ROOT)/make/custom/@RTEMS_BSP@.cfg
+include $(top_srcdir)/../automake/compile.am
+include $(top_srcdir)/../automake/leaf.am
+
+AM_CPPFLAGS += -I$(top_srcdir)/../support/include
+
+LINK_OBJS = $(getentropy01_OBJECTS)
+LINK_LIBS = $(getentropy01_LDLIBS)
+
+getentropy01$(EXEEXT): $(getentropy01_OBJECTS) $(getentropy01_DEPENDENCIES)
+	@rm -f getentropy01$(EXEEXT)
+	$(make-exe)
+
+include $(top_srcdir)/../automake/local.am

testsuites/libtests/getentropy01/getentropy01.doc

@@ -0,0 +1,17 @@
+This file describes the directives and concepts tested by this test set.
+
+test set name: random01
+
+directives:
+
+  getentropy
+
+concepts:
+
+  Ensure that getentropy() works with different sizes of arrays and delivers
+  different values on multiple calls. It is mainly a check that the function
+  does anything at all and does not write over the end of the buffer.
+
+  Note that this test doesn't check any quality of the random numbers. If you
+  need some reliable information about quality you should use something like the
+  Diehard tests.

testsuites/libtests/getentropy01/getentropy01.scn

@@ -0,0 +1,2 @@
+*** TEST GETENTROPY 1 ***
+*** END OF TEST GETENTROPY 1 ***

testsuites/libtests/getentropy01/init.c

@@ -0,0 +1,102 @@
+/*
+ * Copyright (c) 2017 embedded brains GmbH.  All rights reserved.
+ *
+ *  embedded brains GmbH
+ *  Dornierstr. 4
+ *  82178 Puchheim
+ *  Germany
+ *  <rtems@embedded-brains.de>
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rtems.org/license/LICENSE.
+ */
+
+#ifdef HAVE_CONFIG_H
+  #include "config.h"
+#endif
+
+#include "tmacros.h"
+
+#include <rtems.h>
+#include <unistd.h>
+#include <assert.h>
+
+const char rtems_test_name[] = "GETENTROPY 1";
+
+#define TEST_MAX_BYTES 32
+#define TEST_GUARD_BYTES 32
+#define TEST_GUARD 0xA5
+
+static char entropy_buffer1 [TEST_MAX_BYTES + TEST_GUARD_BYTES];
+static char entropy_buffer2 [TEST_MAX_BYTES + TEST_GUARD_BYTES];
+static char guard_buffer [TEST_MAX_BYTES + TEST_GUARD_BYTES];
+
+static void test_getentropy(size_t nr_bytes)
+{
+  int rv;
+  size_t try = 1;
+
+  /*
+   * For very small patterns, the probability that two random patterns are the
+   * same is quite high. Therefore retry the test for these a few times.
+   */
+  if (nr_bytes < 4) {
+    try = 4;
+  }
+
+  do {
+    --try;
+
+    /* Fill buffers with guard pattern */
+    memset(entropy_buffer1, TEST_GUARD, sizeof(entropy_buffer1));
+    memset(entropy_buffer2, TEST_GUARD, sizeof(entropy_buffer2));
+    memset(guard_buffer, TEST_GUARD, sizeof(entropy_buffer2));
+
+    /* Get entropy with the given size */
+    rv = getentropy(entropy_buffer1, nr_bytes);
+    assert(rv == 0);
+    rv = getentropy(entropy_buffer2, nr_bytes);
+    assert(rv == 0);
+
+    /* Check guard pattern */
+    rv = memcmp(entropy_buffer1 + nr_bytes, guard_buffer + nr_bytes,
+        sizeof(entropy_buffer1) - nr_bytes);
+    assert(rv == 0);
+    rv = memcmp(entropy_buffer2 + nr_bytes, guard_buffer + nr_bytes,
+        sizeof(entropy_buffer2) - nr_bytes);
+    assert(rv == 0);
+
+    /* Make sure that buffers are not the same */
+    rv = memcmp(entropy_buffer1, entropy_buffer2, sizeof(entropy_buffer1));
+  } while (try > 0 && rv == 0);
+  assert(rv != 0);
+}
+
+static void Init(rtems_task_argument arg)
+{
+  size_t i;
+
+  TEST_BEGIN();
+
+  for (i = 1; i <= TEST_MAX_BYTES; ++i) {
+    test_getentropy(i);
+  }
+
+  TEST_END();
+
+  rtems_test_exit(0);
+}
+
+#define CONFIGURE_APPLICATION_DOES_NOT_NEED_CLOCK_DRIVER
+#define CONFIGURE_APPLICATION_NEEDS_SIMPLE_CONSOLE_DRIVER
+
+#define CONFIGURE_MAXIMUM_TASKS 1
+
+#define CONFIGURE_INITIAL_EXTENSIONS RTEMS_TEST_INITIAL_EXTENSION
+
+#define CONFIGURE_RTEMS_INIT_TASKS_TABLE
+
+#define CONFIGURE_INIT
+
+#include <rtems/confdefs.h>