Revert r180082 and add a test for SetEnv function

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@180098 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/sanitizer_common/tests/sanitizer_linux_test.cc b/lib/sanitizer_common/tests/sanitizer_linux_test.cc
index 035c11f..0560fb5 100644
--- a/lib/sanitizer_common/tests/sanitizer_linux_test.cc
+++ b/lib/sanitizer_common/tests/sanitizer_linux_test.cc
@@ -20,6 +20,7 @@
 
 #include <pthread.h>
 #include <sched.h>
+#include <stdlib.h>
 
 #include <algorithm>
 #include <vector>
@@ -185,6 +186,14 @@
   ASSERT_TRUE(HasElement(threads_after_extra, extra_tid));
 }
 
+TEST(SanitizerCommon, SetEnvTest) {
+  const char kEnvName[] = "ENV_FOO";
+  SetEnv(kEnvName, "value");
+  EXPECT_STREQ("value", getenv(kEnvName));
+  unsetenv(kEnvName);
+  EXPECT_EQ(0, getenv(kEnvName));
+}
+
 }  // namespace __sanitizer
 
 #endif  // __linux__