Refactor libupdater into a seperate module.

So that we can write native tests for updater functions. This CL adds a
testcase for getprop() function.

Test: mmma bootable/recovery; Run recovery_component_test on device.

Change-Id: Iff4c1ff63c5c71aded2f9686fed6b71cc298c228
diff --git a/tests/component/updater_test.cpp b/tests/component/updater_test.cpp
new file mode 100644
index 0000000..ec9c290
--- /dev/null
+++ b/tests/component/updater_test.cpp
@@ -0,0 +1,71 @@
+/*
+ * Copyright (C) 2016 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 <string>
+
+#include <android-base/properties.h>
+#include <gtest/gtest.h>
+
+#include "edify/expr.h"
+#include "error_code.h"
+#include "updater/install.h"
+
+struct selabel_handle *sehandle = nullptr;
+
+static void expect(const char* expected, const char* expr_str,
+                   ErrorCode error_code, CauseCode cause_code) {
+    Expr* e;
+    int error_count;
+    EXPECT_EQ(parse_string(expr_str, &e, &error_count), 0);
+
+    State state(expr_str, nullptr);
+
+    char* result = Evaluate(&state, e);
+
+    if (expected == nullptr) {
+        EXPECT_EQ(nullptr, result);
+    } else {
+        EXPECT_STREQ(expected, result);
+    }
+
+    EXPECT_EQ(error_code, state.error_code);
+    EXPECT_EQ(cause_code, state.cause_code);
+
+    free(result);
+}
+
+class UpdaterTest : public ::testing::Test {
+  protected:
+    virtual void SetUp() {
+        RegisterBuiltins();
+        RegisterInstallFunctions();
+        FinishRegistration();
+    }
+};
+
+TEST_F(UpdaterTest, getprop) {
+    expect(android::base::GetProperty("ro.product.device", "").c_str(),
+           "getprop(\"ro.product.device\")",
+           kNoError, kNoCause);
+
+    expect(android::base::GetProperty("ro.build.fingerprint", "").c_str(),
+           "getprop(\"ro.build.fingerprint\")",
+           kNoError, kNoCause);
+
+    // getprop() accepts only one parameter.
+    expect(nullptr, "getprop()", kNoError, kArgsParsingFailure);
+    expect(nullptr, "getprop(\"arg1\", \"arg2\")", kNoError, kArgsParsingFailure);
+}