Upgrade to the current NetBSD rand implementation.

Also add basic unit tests.

Change-Id: I7fc7ef61d47c1e8fdf8b8eff67a635220c3afd56

1 files changed, 59 insertions, 0 deletions

diff --git a/tests/stdlib_test.cpp b/tests/stdlib_test.cpp
new file mode 100644
index 000000000..a9c62d40a
--- /dev/null
+++ b/tests/stdlib_test.cpp
@@ -0,0 +1,59 @@
+/*
+ * Copyright (C) 2012 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <gtest/gtest.h>
+
+#include <stdlib.h>
+
+TEST(stdlib, drand48) {
+  srand48(0x01020304);
+  EXPECT_DOUBLE_EQ(0.65619299195623526, drand48());
+  EXPECT_DOUBLE_EQ(0.18522597229772941, drand48());
+  EXPECT_DOUBLE_EQ(0.42015087072844537, drand48());
+  EXPECT_DOUBLE_EQ(0.061637783047395089, drand48());
+}
+
+TEST(stdlib, lrand48_random_rand) {
+  srand48(0x01020304);
+  EXPECT_EQ(1409163720, lrand48());
+  EXPECT_EQ(397769746, lrand48());
+  EXPECT_EQ(902267124, lrand48());
+  EXPECT_EQ(132366131, lrand48());
+
+#if __BIONIC__
+  // On bionic, random(3) is equivalent to lrand48...
+  srandom(0x01020304);
+  EXPECT_EQ(1409163720, random());
+  EXPECT_EQ(397769746, random());
+  EXPECT_EQ(902267124, random());
+  EXPECT_EQ(132366131, random());
+
+  // ...and rand(3) is the bottom 32 bits.
+  srand(0x01020304);
+  EXPECT_EQ(static_cast<int>(1409163720), rand());
+  EXPECT_EQ(static_cast<int>(397769746), rand());
+  EXPECT_EQ(static_cast<int>(902267124), rand());
+  EXPECT_EQ(static_cast<int>(132366131), rand());
+#endif
+}
+
+TEST(stdlib, mrand48) {
+  srand48(0x01020304);
+  EXPECT_EQ(-1476639856, mrand48());
+  EXPECT_EQ(795539493, mrand48());
+  EXPECT_EQ(1804534249, mrand48());
+  EXPECT_EQ(264732262, mrand48());
+}