Add simple fake for native service manager.

Reusing the existing binder-based native service manager has
proved problematic in host/test environments.

So as a workaround, this commit creates a IServiceManager native
implementation that can be communicated with directly.

Bug: 147595993
Test: m fakeservicemanager_test; fakeservicemanager_test
Change-Id: Icfa6f2fd314bd5a7b3d5e8a064b487f92b99b133

4 files changed, 289 insertions, 0 deletions

diff --git a/libs/fakeservicemanager/Android.bp b/libs/fakeservicemanager/Android.bp
new file mode 100644
index 0000000000..de32ff4e64
--- /dev/null
+++ b/libs/fakeservicemanager/Android.bp
@@ -0,0 +1,25 @@
+cc_defaults {
+    name: "fakeservicemanager_defaults",
+    srcs: [
+        "ServiceManager.cpp",
+    ],
+
+    shared_libs: [
+        "libbinder",
+        "libutils",
+    ],
+}
+
+cc_library {
+    name: "libfakeservicemanager",
+    defaults: ["fakeservicemanager_defaults"],
+}
+
+cc_test_host {
+    name: "fakeservicemanager_test",
+    defaults: ["fakeservicemanager_defaults"],
+    srcs: [
+        "test_sm.cpp",
+    ],
+    static_libs: ["libgmock"],
+}
diff --git a/libs/fakeservicemanager/ServiceManager.cpp b/libs/fakeservicemanager/ServiceManager.cpp
new file mode 100644
index 0000000000..69643249e3
--- /dev/null
+++ b/libs/fakeservicemanager/ServiceManager.cpp
@@ -0,0 +1,64 @@
+/*
+ * Copyright (C) 2020 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 "ServiceManager.h"
+
+namespace android {
+
+ServiceManager::ServiceManager() {}
+
+sp<IBinder> ServiceManager::getService( const String16& name) const {
+    // Servicemanager is single-threaded and cannot block. This method exists for legacy reasons.
+    return checkService(name);
+}
+
+sp<IBinder> ServiceManager::checkService( const String16& name) const {
+    auto it = mNameToService.find(name);
+    if (it == mNameToService.end()) {
+        return nullptr;
+    }
+    return it->second;
+}
+
+status_t ServiceManager::addService(const String16& name, const sp<IBinder>& service,
+                                bool /*allowIsolated*/,
+                                int /*dumpsysFlags*/) {
+    mNameToService[name] = service;
+    return NO_ERROR;
+}
+
+Vector<String16> ServiceManager::listServices(int /*dumpsysFlags*/) {
+    Vector<String16> services;
+    for (auto const& [name, service] : mNameToService) {
+        (void) service;
+         services.push_back(name);
+    }
+  return services;
+}
+
+IBinder* ServiceManager::onAsBinder() {
+    return nullptr;
+}
+
+sp<IBinder> ServiceManager::waitForService(const String16& name) {
+    return checkService(name);
+}
+
+bool ServiceManager::isDeclared(const String16& name) {
+    return mNameToService.find(name) != mNameToService.end();
+}
+
+}  // namespace android
diff --git a/libs/fakeservicemanager/ServiceManager.h b/libs/fakeservicemanager/ServiceManager.h
new file mode 100644
index 0000000000..62311d4727
--- /dev/null
+++ b/libs/fakeservicemanager/ServiceManager.h
@@ -0,0 +1,74 @@
+/*
+ * Copyright (C) 2020 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.
+ */
+
+#pragma once
+
+#include <binder/IServiceManager.h>
+
+#include <map>
+
+namespace android {
+
+/**
+ * A local host simple implementation of IServiceManager, that does not
+ * communicate over binder.
+*/
+class ServiceManager : public IServiceManager {
+public:
+    ServiceManager();
+
+    /**
+     * Equivalent of checkService.
+     */
+    sp<IBinder> getService( const String16& name) const override;
+
+    /**
+     * Retrieve an existing service, non-blocking.
+     */
+    sp<IBinder> checkService( const String16& name) const override;
+
+    /**
+     * Register a service.
+     */
+    status_t addService(const String16& name, const sp<IBinder>& service,
+                        bool allowIsolated = false,
+                        int dumpsysFlags = DUMP_FLAG_PRIORITY_DEFAULT) override;
+
+    /**
+     * Return list of all existing services.
+     */
+    Vector<String16> listServices(int dumpsysFlags = 0) override;
+
+    IBinder* onAsBinder() override;
+
+    /**
+     * Effectively no-oped in this implementation - equivalent to checkService.
+     */
+    sp<IBinder> waitForService(const String16& name) override;
+
+    /**
+     * Check if a service is declared (e.g. VINTF manifest).
+     *
+     * If this returns true, waitForService should always be able to return the
+     * service.
+     */
+     bool isDeclared(const String16& name) override;
+
+private:
+    std::map<String16, sp<IBinder>> mNameToService;
+};
+
+}  // namespace android
diff --git a/libs/fakeservicemanager/test_sm.cpp b/libs/fakeservicemanager/test_sm.cpp
new file mode 100644
index 0000000000..71e5abe126
--- /dev/null
+++ b/libs/fakeservicemanager/test_sm.cpp
@@ -0,0 +1,126 @@
+/*
+ * Copyright (C) 2019 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 <gmock/gmock.h>
+
+#include <binder/Binder.h>
+#include <binder/ProcessState.h>
+#include <binder/IServiceManager.h>
+
+#include "ServiceManager.h"
+
+using android::sp;
+using android::BBinder;
+using android::IBinder;
+using android::OK;
+using android::status_t;
+using android::ServiceManager;
+using android::String16;
+using android::IServiceManager;
+using testing::ElementsAre;
+
+static sp<IBinder> getBinder() {
+    class LinkableBinder : public BBinder {
+        status_t linkToDeath(const sp<DeathRecipient>&, void*, uint32_t) override {
+            // let SM linkToDeath
+            return OK;
+        }
+    };
+
+    return new LinkableBinder;
+}
+
+TEST(AddService, HappyHappy) {
+    auto sm = new ServiceManager();
+    EXPECT_EQ(sm->addService(String16("foo"), getBinder(), false /*allowIsolated*/,
+        IServiceManager::DUMP_FLAG_PRIORITY_DEFAULT), OK);
+}
+
+TEST(AddService, HappyOverExistingService) {
+    auto sm = new ServiceManager();
+    EXPECT_EQ(sm->addService(String16("foo"), getBinder(), false /*allowIsolated*/,
+        IServiceManager::DUMP_FLAG_PRIORITY_DEFAULT), OK);
+    EXPECT_EQ(sm->addService(String16("foo"), getBinder(), false /*allowIsolated*/,
+        IServiceManager::DUMP_FLAG_PRIORITY_DEFAULT), OK);
+}
+
+TEST(GetService, HappyHappy) {
+    auto sm = new ServiceManager();
+    sp<IBinder> service = getBinder();
+
+    EXPECT_EQ(sm->addService(String16("foo"), service, false /*allowIsolated*/,
+        IServiceManager::DUMP_FLAG_PRIORITY_DEFAULT), OK);
+
+    EXPECT_EQ(sm->getService(String16("foo")), service);
+}
+
+TEST(GetService, NonExistant) {
+    auto sm = new ServiceManager();
+
+    EXPECT_EQ(sm->getService(String16("foo")), nullptr);
+}
+
+TEST(ListServices, AllServices) {
+    auto sm = new ServiceManager();
+
+    EXPECT_EQ(sm->addService(String16("sd"), getBinder(), false /*allowIsolated*/,
+        IServiceManager::DUMP_FLAG_PRIORITY_DEFAULT), OK);
+    EXPECT_EQ(sm->addService(String16("sc"), getBinder(), false /*allowIsolated*/,
+        IServiceManager::DUMP_FLAG_PRIORITY_NORMAL), OK);
+    EXPECT_EQ(sm->addService(String16("sb"), getBinder(), false /*allowIsolated*/,
+        IServiceManager::DUMP_FLAG_PRIORITY_HIGH), OK);
+    EXPECT_EQ(sm->addService(String16("sa"), getBinder(), false /*allowIsolated*/,
+        IServiceManager::DUMP_FLAG_PRIORITY_CRITICAL), OK);
+
+    android::Vector<String16> out = sm->listServices(IServiceManager::DUMP_FLAG_PRIORITY_ALL);
+
+    // all there and in the right order
+    EXPECT_THAT(out, ElementsAre(String16("sa"), String16("sb"), String16("sc"),
+        String16("sd")));
+}
+
+TEST(WaitForService, NonExistant) {
+    auto sm = new ServiceManager();
+
+    EXPECT_EQ(sm->waitForService(String16("foo")), nullptr);
+}
+
+TEST(WaitForService, HappyHappy) {
+    auto sm = new ServiceManager();
+    sp<IBinder> service = getBinder();
+
+    EXPECT_EQ(sm->addService(String16("foo"), service, false /*allowIsolated*/,
+        IServiceManager::DUMP_FLAG_PRIORITY_DEFAULT), OK);
+
+    EXPECT_EQ(sm->waitForService(String16("foo")), service);
+}
+
+TEST(IsDeclared, NonExistant) {
+    auto sm = new ServiceManager();
+
+    EXPECT_FALSE(sm->isDeclared(String16("foo")));
+}
+
+TEST(IsDeclared, HappyHappy) {
+    auto sm = new ServiceManager();
+    sp<IBinder> service = getBinder();
+
+    EXPECT_EQ(sm->addService(String16("foo"), service, false /*allowIsolated*/,
+        IServiceManager::DUMP_FLAG_PRIORITY_DEFAULT), OK);
+
+    EXPECT_TRUE(sm->isDeclared(String16("foo")));
+}