MediaCas: add MediaCasService

This CL adds API only without implementation.

bug: 22804304
Change-Id: Ibb5a29cc616ec0af81957b2bfe1419c482591753
diff --git a/services/mediadrm/Android.mk b/services/mediadrm/Android.mk
index e72236d..87fddd4 100644
--- a/services/mediadrm/Android.mk
+++ b/services/mediadrm/Android.mk
@@ -17,6 +17,7 @@
 include $(CLEAR_VARS)
 
 LOCAL_SRC_FILES:= \
+    MediaCasService.cpp \
     MediaDrmService.cpp \
     main_mediadrmserver.cpp
 
diff --git a/services/mediadrm/FactoryLoader.h b/services/mediadrm/FactoryLoader.h
new file mode 100644
index 0000000..1e03e9b
--- /dev/null
+++ b/services/mediadrm/FactoryLoader.h
@@ -0,0 +1,220 @@
+/*
+ * Copyright (C) 2017 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.
+ */
+
+#ifndef MEDIA_CAS_LOADER_H_
+#define MEDIA_CAS_LOADER_H_
+
+#include <dirent.h>
+#include <dlfcn.h>
+#include <media/SharedLibrary.h>
+#include <utils/KeyedVector.h>
+#include <utils/Mutex.h>
+
+namespace android {
+using namespace std;
+using namespace media;
+using namespace MediaCas;
+
+template <class T>
+class FactoryLoader {
+public:
+    FactoryLoader(const char *name) :
+        mFactory(NULL), mCreateFactoryFuncName(name) {}
+
+    virtual ~FactoryLoader() { closeFactory(); }
+
+    bool findFactoryForScheme(
+            int32_t CA_system_id,
+            sp<SharedLibrary> *library = NULL,
+            T** factory = NULL);
+
+    bool enumeratePlugins(vector<ParcelableCasPluginDescriptor>* results);
+
+private:
+    typedef T*(*CreateFactoryFunc)();
+
+    Mutex mMapLock;
+    T* mFactory;
+    const char *mCreateFactoryFuncName;
+    sp<SharedLibrary> mLibrary;
+    KeyedVector<int32_t, String8> mCASystemIdToLibraryPathMap;
+    KeyedVector<String8, wp<SharedLibrary> > mLibraryPathToOpenLibraryMap;
+
+    bool loadFactoryForSchemeFromPath(
+            const String8 &path,
+            int32_t CA_system_id,
+            sp<SharedLibrary> *library,
+            T** factory);
+
+    bool queryPluginsFromPath(
+            const String8 &path,
+            vector<ParcelableCasPluginDescriptor>* results);
+
+    bool openFactory(const String8 &path);
+    void closeFactory();
+};
+
+template <class T>
+bool FactoryLoader<T>::findFactoryForScheme(
+        int32_t CA_system_id, sp<SharedLibrary> *library, T** factory) {
+    if (library != NULL) {
+        library->clear();
+    }
+    if (factory != NULL) {
+        *factory = NULL;
+    }
+
+    Mutex::Autolock autoLock(mMapLock);
+
+    // first check cache
+    ssize_t index = mCASystemIdToLibraryPathMap.indexOfKey(CA_system_id);
+    if (index >= 0) {
+        return loadFactoryForSchemeFromPath(
+                mCASystemIdToLibraryPathMap[index],
+                CA_system_id, library, factory);
+    }
+
+    // no luck, have to search
+    String8 dirPath("/vendor/lib/mediacas");
+    DIR* pDir = opendir(dirPath.string());
+
+    if (pDir == NULL) {
+        ALOGE("Failed to open plugin directory %s", dirPath.string());
+        return false;
+    }
+
+    struct dirent* pEntry;
+    while ((pEntry = readdir(pDir))) {
+        String8 pluginPath = dirPath + "/" + pEntry->d_name;
+        if (pluginPath.getPathExtension() == ".so") {
+            if (loadFactoryForSchemeFromPath(
+                    pluginPath, CA_system_id, library, factory)) {
+                mCASystemIdToLibraryPathMap.add(CA_system_id, pluginPath);
+                closedir(pDir);
+
+                return true;
+            }
+        }
+    }
+
+    closedir(pDir);
+
+    ALOGE("Failed to find plugin");
+    return false;
+}
+
+template <class T>
+bool FactoryLoader<T>::enumeratePlugins(
+        vector<ParcelableCasPluginDescriptor>* results) {
+    ALOGI("enumeratePlugins");
+
+    results->clear();
+
+    String8 dirPath("/vendor/lib/mediacas");
+    DIR* pDir = opendir(dirPath.string());
+
+    if (pDir == NULL) {
+        ALOGE("Failed to open plugin directory %s", dirPath.string());
+        return false;
+    }
+
+    Mutex::Autolock autoLock(mMapLock);
+
+    struct dirent* pEntry;
+    while ((pEntry = readdir(pDir))) {
+        String8 pluginPath = dirPath + "/" + pEntry->d_name;
+        if (pluginPath.getPathExtension() == ".so") {
+            queryPluginsFromPath(pluginPath, results);
+        }
+    }
+    return true;
+}
+
+template <class T>
+bool FactoryLoader<T>::loadFactoryForSchemeFromPath(
+        const String8 &path, int32_t CA_system_id,
+        sp<SharedLibrary> *library, T** factory) {
+    closeFactory();
+
+    if (!openFactory(path) || !mFactory->isSystemIdSupported(CA_system_id)) {
+        closeFactory();
+        return false;
+    }
+
+    if (library != NULL) {
+        *library = mLibrary;
+    }
+    if (factory != NULL) {
+        *factory = mFactory;
+    }
+    return true;
+}
+
+template <class T>
+bool FactoryLoader<T>::queryPluginsFromPath(
+        const String8 &path, vector<ParcelableCasPluginDescriptor>* results) {
+    closeFactory();
+
+    vector<CasPluginDescriptor> descriptors;
+    if (!openFactory(path) || mFactory->queryPlugins(&descriptors) != OK) {
+        closeFactory();
+        return false;
+    }
+
+    for (auto it = descriptors.begin(); it != descriptors.end(); it++) {
+        results->push_back(ParcelableCasPluginDescriptor(
+                it->CA_system_id, it->name));
+    }
+    return true;
+}
+
+template <class T>
+bool FactoryLoader<T>::openFactory(const String8 &path) {
+    // get strong pointer to open shared library
+    ssize_t index = mLibraryPathToOpenLibraryMap.indexOfKey(path);
+    if (index >= 0) {
+        mLibrary = mLibraryPathToOpenLibraryMap[index].promote();
+    } else {
+        index = mLibraryPathToOpenLibraryMap.add(path, NULL);
+    }
+
+    if (!mLibrary.get()) {
+        mLibrary = new SharedLibrary(path);
+        if (!*mLibrary) {
+            return false;
+        }
+
+        mLibraryPathToOpenLibraryMap.replaceValueAt(index, mLibrary);
+    }
+
+    CreateFactoryFunc createFactory =
+        (CreateFactoryFunc)mLibrary->lookup(mCreateFactoryFuncName);
+    if (createFactory == NULL || (mFactory = createFactory()) == NULL) {
+        return false;
+    }
+    return true;
+}
+
+template <class T>
+void FactoryLoader<T>::closeFactory() {
+    delete mFactory;
+    mFactory = NULL;
+    mLibrary.clear();
+}
+
+} // namespace android
+
+#endif // MEDIA_CAS_LOADER_H_
diff --git a/services/mediadrm/MediaCasService.cpp b/services/mediadrm/MediaCasService.cpp
new file mode 100644
index 0000000..c111283
--- /dev/null
+++ b/services/mediadrm/MediaCasService.cpp
@@ -0,0 +1,119 @@
+/*
+ * Copyright (C) 2017 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.
+ */
+
+//#define LOG_NDEBUG 0
+#define LOG_TAG "MediaCasService"
+
+#include <binder/IServiceManager.h>
+#include <media/cas/CasAPI.h>
+#include <media/cas/DescramblerAPI.h>
+#include <media/CasImpl.h>
+#include <media/DescramblerImpl.h>
+#include <utils/Log.h>
+#include <utils/List.h>
+#include "MediaCasService.h"
+#include <android/media/ICasListener.h>
+
+namespace android {
+
+//static
+void MediaCasService::instantiate() {
+    defaultServiceManager()->addService(
+            String16("media.cas"), new MediaCasService());
+}
+
+MediaCasService::MediaCasService() :
+    mCasLoader(new FactoryLoader<CasFactory>("createCasFactory")),
+    mDescramblerLoader(new FactoryLoader<DescramblerFactory>(
+            "createDescramblerFactory")) {
+}
+
+MediaCasService::~MediaCasService() {
+    delete mCasLoader;
+    delete mDescramblerLoader;
+}
+
+Status MediaCasService::enumeratePlugins(
+        vector<ParcelableCasPluginDescriptor>* results) {
+    ALOGV("enumeratePlugins");
+
+    mCasLoader->enumeratePlugins(results);
+
+    return Status::ok();
+}
+
+Status MediaCasService::isSystemIdSupported(
+        int32_t CA_system_id, bool* result) {
+    ALOGV("isSystemIdSupported: CA_system_id=%d", CA_system_id);
+
+    *result = mCasLoader->findFactoryForScheme(CA_system_id);
+
+    return Status::ok();
+}
+
+Status MediaCasService::createPlugin(
+        int32_t CA_system_id,
+        const sp<ICasListener> &listener,
+        sp<ICas>* result) {
+    ALOGV("createPlugin: CA_system_id=%d", CA_system_id);
+
+    result->clear();
+
+    CasFactory *factory;
+    sp<SharedLibrary> library;
+    if (mCasLoader->findFactoryForScheme(CA_system_id, &library, &factory)) {
+        CasPlugin *plugin = NULL;
+        sp<CasImpl> casImpl = new CasImpl(listener);
+        if (factory->createPlugin(CA_system_id, (uint64_t)casImpl.get(),
+                &CasImpl::OnEvent, &plugin) == OK && plugin != NULL) {
+            casImpl->init(library, plugin);
+            *result = casImpl;
+        }
+    }
+
+    return Status::ok();
+}
+
+Status MediaCasService::isDescramblerSupported(
+        int32_t CA_system_id, bool* result) {
+    ALOGV("isDescramblerSupported: CA_system_id=%d", CA_system_id);
+
+    *result = mDescramblerLoader->findFactoryForScheme(CA_system_id);
+
+    return Status::ok();
+}
+
+Status MediaCasService::createDescrambler(
+        int32_t CA_system_id, sp<IDescrambler>* result) {
+    ALOGV("createDescrambler: CA_system_id=%d", CA_system_id);
+
+    result->clear();
+
+    DescramblerFactory *factory;
+    sp<SharedLibrary> library;
+    if (mDescramblerLoader->findFactoryForScheme(
+            CA_system_id, &library, &factory)) {
+        DescramblerPlugin *plugin = NULL;
+        if (factory->createPlugin(CA_system_id, &plugin) == OK
+                && plugin != NULL) {
+            *result = new DescramblerImpl(library, plugin);
+        }
+    }
+
+    return Status::ok();
+}
+
+} // namespace android
diff --git a/services/mediadrm/MediaCasService.h b/services/mediadrm/MediaCasService.h
new file mode 100644
index 0000000..cb828f2
--- /dev/null
+++ b/services/mediadrm/MediaCasService.h
@@ -0,0 +1,60 @@
+/*
+ * Copyright (C) 2017 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.
+ */
+
+#ifndef MEDIA_CAS_SERVICE_H_
+#define MEDIA_CAS_SERVICE_H_
+
+#include <android/media/BnMediaCasService.h>
+
+#include "FactoryLoader.h"
+
+namespace android {
+using binder::Status;
+struct CasFactory;
+struct DescramblerFactory;
+
+class MediaCasService : public BnMediaCasService {
+public:
+    static void instantiate();
+
+    virtual Status enumeratePlugins(
+            vector<ParcelableCasPluginDescriptor>* results) override;
+
+    virtual Status isSystemIdSupported(
+            int32_t CA_system_id, bool* result) override;
+
+    virtual Status createPlugin(
+            int32_t CA_system_id,
+            const sp<ICasListener> &listener,
+            sp<ICas>* result) override;
+
+    virtual Status isDescramblerSupported(
+            int32_t CA_system_id, bool* result) override;
+
+    virtual Status createDescrambler(
+            int32_t CA_system_id, sp<IDescrambler>* result) override;
+
+private:
+    FactoryLoader<CasFactory> *mCasLoader;
+    FactoryLoader<DescramblerFactory> *mDescramblerLoader;
+
+    MediaCasService();
+    virtual ~MediaCasService();
+};
+
+} // namespace android
+
+#endif // MEDIA_CAS_SERVICE_H_
diff --git a/services/mediadrm/main_mediadrmserver.cpp b/services/mediadrm/main_mediadrmserver.cpp
index b767b8c..b685ae0 100644
--- a/services/mediadrm/main_mediadrmserver.cpp
+++ b/services/mediadrm/main_mediadrmserver.cpp
@@ -27,6 +27,7 @@
 #include <cutils/properties.h>
 #include <utils/Log.h>
 #include "MediaDrmService.h"
+#include "MediaCasService.h"
 
 using namespace android;
 
@@ -38,6 +39,7 @@
     sp<IServiceManager> sm = defaultServiceManager();
     ALOGI("ServiceManager: %p", sm.get());
     MediaDrmService::instantiate();
+    MediaCasService::instantiate();
     ProcessState::self()->startThreadPool();
     IPCThreadState::self()->joinThreadPool();
 }