Basic bcat:u implementation

A basic `bcat:u` implementation to prevent titles such as "Kirby and the Forgotten Land" dependent on BCAT support from crashing due to the lack of an implementation.

app/CMakeLists.txt

@@ -251,6 +251,8 @@ add_library(skyline SHARED
         ${source_DIR}/skyline/services/am/storage/IStorageAccessor.cpp
         ${source_DIR}/skyline/services/am/applet/ILibraryAppletAccessor.cpp
         ${source_DIR}/skyline/services/am/applet/IApplet.cpp
+        ${source_DIR}/skyline/services/bcat/IServiceCreator.cpp
+        ${source_DIR}/skyline/services/bcat/IBcatService.cpp
         ${source_DIR}/skyline/applet/applet_creator.cpp
         ${source_DIR}/skyline/applet/controller_applet.cpp
         ${source_DIR}/skyline/services/codec/IHardwareOpusDecoder.cpp

app/src/main/cpp/skyline/services/bcat/IBcatService.cpp

@@ -0,0 +1,8 @@
+// SPDX-License-Identifier: MPL-2.0
+// Copyright © 2022 Skyline Team and Contributors (https://github.com/skyline-emu/)
+
+#include "IBcatService.h"
+
+namespace skyline::service::bcat {
+    IBcatService::IBcatService(const DeviceState &state, ServiceManager &manager) : BaseService(state, manager) {}
+}

app/src/main/cpp/skyline/services/bcat/IBcatService.h

@@ -0,0 +1,17 @@
+// SPDX-License-Identifier: MPL-2.0
+// Copyright © 2022 Skyline Team and Contributors (https://github.com/skyline-emu/)
+
+#pragma once
+
+#include <services/serviceman.h>
+
+namespace skyline::service::bcat {
+    /**
+     * @brief IBcatService is used to interact with BCAT (Background Content Asymmetric synchronized delivery and Transmission)
+     * @url https://switchbrew.org/wiki/BCAT_services#IBcatService
+     */
+    class IBcatService : public BaseService {
+      public:
+        IBcatService(const DeviceState &state, ServiceManager &manager);
+    };
+}

app/src/main/cpp/skyline/services/bcat/IServiceCreator.cpp

@@ -0,0 +1,13 @@
+// SPDX-License-Identifier: MPL-2.0
+// Copyright © 2022 Skyline Team and Contributors (https://github.com/skyline-emu/)
+
+#include "IServiceCreator.h"
+
+namespace skyline::service::bcat {
+    IServiceCreator::IServiceCreator(const DeviceState &state, ServiceManager &manager) : BaseService(state, manager) {}
+
+    Result IServiceCreator::CreateBcatService(type::KSession &session, ipc::IpcRequest &request, ipc::IpcResponse &response) {
+        manager.RegisterService(SRVREG(IBcatService), session, response);
+        return {};
+    }
+}

app/src/main/cpp/skyline/services/bcat/IServiceCreator.h

@@ -0,0 +1,28 @@
+// SPDX-License-Identifier: MPL-2.0
+// Copyright © 2022 Skyline Team and Contributors (https://github.com/skyline-emu/)
+
+#pragma once
+
+#include <services/serviceman.h>
+#include "IBcatService.h"
+
+namespace skyline::service::bcat {
+    /**
+     * @brief IServiceCreator is used to create per-process/per-title service instances for BCAT
+     * @url https://switchbrew.org/wiki/BCAT_services#bcat:a.2C_bcat:m.2C_bcat:u.2C_bcat:s
+     */
+    class IServiceCreator : public BaseService {
+      public:
+        IServiceCreator(const DeviceState &state, ServiceManager &manager);
+
+        /**
+         * @brief Takes an input u64 ProcessId, returns an #IBcatService
+         * @url https://switchbrew.org/wiki/BCAT_services#bcat:a.2C_bcat:m.2C_bcat:u.2C_bcat:s
+         */
+        Result CreateBcatService(type::KSession &session, ipc::IpcRequest &request, ipc::IpcResponse &response);
+
+        SERVICE_DECL(
+            SFUNC(0x0, IServiceCreator, CreateBcatService)
+        )
+    };
+}

app/src/main/cpp/skyline/services/serviceman.cpp

@@ -11,6 +11,7 @@
 #include "am/IAllSystemAppletProxiesService.h"
 #include "audio/IAudioOutManager.h"
 #include "audio/IAudioRendererManager.h"
+#include "bcat/IServiceCreator.h"
 #include "codec/IHardwareOpusDecoderManager.h"
 #include "fatalsrv/IService.h"
 #include "hid/IHidServer.h"
@@ -109,6 +110,7 @@ namespace skyline::service {
             SERVICE_CASE(ssl::ISslService, "ssl")
             SERVICE_CASE(prepo::IPrepoService, "prepo:u")
             SERVICE_CASE(mmnv::IRequest, "mm:u")
+            SERVICE_CASE(bcat::IServiceCreator, "bcat:u")
             default:
                 std::string_view nameString(span(reinterpret_cast<char *>(&name), sizeof(name)).as_string(true));
                 throw std::out_of_range(fmt::format("CreateService called with an unknown service name: {}", nameString));