[hle,display,overlay,starter,hid] add overlay functions, starter applet (initially), HID handheld for system applets and fw21 stubs (#3080)

Adds fully functional overlay display.
- Enable Overlay Applet via "View" -> "Enable Overlay Display Applet"
- Open the overlay by pressing the home button for over 1s
- Can adjust volume
- Can toggle airplane mode (if on WiFi, maybe if overlay is enabled pretend to be on WiFi?)
- Future TODO(?): Adjust Brightness implementation for host system
- Inputs are properly registered. e.g. if overlay open, application does not register inputs.

You can control volume and airplane mode outside of the emulator window

Reviewed-on: https://git.eden-emu.dev/eden-emu/eden/pulls/3080
Reviewed-by: CamilleLaVey <camillelavey99@gmail.com>
Reviewed-by: crueter <crueter@eden-emu.dev>
Co-authored-by: Maufeat <sahyno1996@gmail.com>
Co-committed-by: Maufeat <sahyno1996@gmail.com>

src/core/hle/service/psc/ovln/ovln_types.h

@@ -1,3 +1,6 @@
+// SPDX-FileCopyrightText: Copyright 2025 Eden Emulator Project
+// SPDX-License-Identifier: GPL-3.0-or-later
+
 // SPDX-FileCopyrightText: Copyright 2024 yuzu Emulator Project
 // SPDX-License-Identifier: GPL-2.0-or-later
 
@@ -18,4 +21,13 @@ union MessageFlags {
 };
 static_assert(sizeof(MessageFlags) == 0x8, "MessageFlags has incorrect size");
 
+struct SourceName {
+    char name[0x16];
+
+    const char* GetString() const {
+        return name;
+    }
+};
+;
+
 } // namespace Service::PSC

src/core/hle/service/psc/ovln/receiver.cpp

@@ -1,24 +1,118 @@
+// SPDX-FileCopyrightText: Copyright 2025 Eden Emulator Project
+// SPDX-License-Identifier: GPL-3.0-or-later
+
 // SPDX-FileCopyrightText: Copyright 2024 yuzu Emulator Project
 // SPDX-License-Identifier: GPL-2.0-or-later
 
 #include "core/hle/service/psc/ovln/receiver.h"
+#include "core/hle/service/cmif_serialization.h"
 
 namespace Service::PSC {
 
-IReceiver::IReceiver(Core::System& system_) : ServiceFramework{system_, "IReceiver"} {
+IReceiver::IReceiver(Core::System& system_)
+    : ServiceFramework{system_, "IReceiver"}, service_context{system_, "IReceiver"} {
     // clang-format off
         static const FunctionInfo functions[] = {
-            {0, nullptr, "AddSource"},
-            {1, nullptr, "RemoveSource"},
-            {2, nullptr, "GetReceiveEventHandle"},
-            {3, nullptr, "Receive"},
-            {4, nullptr, "ReceiveWithTick"},
+            {0, D<&IReceiver::AddSource>, "AddSource"},
+            {1, D<&IReceiver::RemoveSource>, "RemoveSource"},
+            {2, D<&IReceiver::GetReceiveEventHandle>, "GetReceiveEventHandle"},
+            {3, D<&IReceiver::Receive>, "Receive"},
+            {4, D<&IReceiver::ReceiveWithTick>, "ReceiveWithTick"},
         };
     // clang-format on
 
     RegisterHandlers(functions);
+
+    receive_event = service_context.CreateEvent("IReceiver::ReceiveEvent");
 }
 
-IReceiver::~IReceiver() = default;
+IReceiver::~IReceiver() {
+    service_context.CloseEvent(receive_event);
+}
+
+Result IReceiver::AddSource(SourceName source_name) {
+    const std::string name = source_name.GetString();
+    LOG_INFO(Service_PSC, "called: source_name={}", name);
+
+    // Add source if it doesn't already exist
+    if (message_sources.find(name) == message_sources.end()) {
+        message_sources[name] = {};
+    }
+
+    R_SUCCEED();
+}
+
+Result IReceiver::RemoveSource(SourceName source_name) {
+    const std::string name = source_name.GetString();
+    LOG_INFO(Service_PSC, "called: source_name={}", name);
+
+    // Remove source if it exists
+    message_sources.erase(name);
+
+    R_SUCCEED();
+}
+
+Result IReceiver::GetReceiveEventHandle(OutCopyHandle<Kernel::KReadableEvent> out_event) {
+    LOG_INFO(Service_PSC, "called");
+    *out_event = &receive_event->GetReadableEvent();
+    R_SUCCEED();
+}
+
+Result IReceiver::Receive(Out<OverlayNotification> out_notification, Out<MessageFlags> out_flags) {
+    u64 tick;
+    return ReceiveWithTick(out_notification, out_flags, Out<u64>(&tick));
+}
+
+Result IReceiver::ReceiveWithTick(Out<OverlayNotification> out_notification,
+                                   Out<MessageFlags> out_flags, Out<u64> out_tick) {
+    LOG_DEBUG(Service_PSC, "called");
+
+    // Find the message with the lowest ID across all sources
+    const std::string* target_source = nullptr;
+    size_t target_index = 0;
+
+    for (const auto& [source_name, messages] : message_sources) {
+        if (!messages.empty()) {
+            if (target_source == nullptr) {
+                target_source = &source_name;
+                target_index = 0;
+            }
+            // Note: In the real implementation, we would track message IDs
+            // For now, just use FIFO order
+        }
+    }
+
+    if (target_source != nullptr) {
+        auto& messages = message_sources[*target_source];
+        *out_notification = messages[target_index].first;
+        *out_flags = messages[target_index].second;
+        *out_tick = 0; // TODO: Implement tick tracking
+
+        // Remove the message
+        messages.erase(messages.begin() + target_index);
+
+        // Clear event if no more messages
+        bool has_messages = false;
+        for (const auto& [_, msgs] : message_sources) {
+            if (!msgs.empty()) {
+                has_messages = true;
+                break;
+            }
+        }
+        if (!has_messages) {
+            receive_event->Clear();
+        }
+
+        R_SUCCEED();
+    }
+
+    // No messages available
+    *out_notification = {};
+    *out_flags = {};
+    *out_tick = 0;
+
+    LOG_WARNING(Service_PSC, "No messages available");
+    R_THROW(ResultUnknown); // TODO: Use proper OvlnResult::NoMessages when available
+}
 
 } // namespace Service::PSC

src/core/hle/service/psc/ovln/receiver.h

@@ -1,9 +1,23 @@
+// SPDX-FileCopyrightText: Copyright 2025 Eden Emulator Project
+// SPDX-License-Identifier: GPL-3.0-or-later
+
 // SPDX-FileCopyrightText: Copyright 2024 yuzu Emulator Project
 // SPDX-License-Identifier: GPL-2.0-or-later
 
 #pragma once
 
+#include <map>
+#include <memory>
+#include <string>
+#include "core/hle/result.h"
+#include "core/hle/service/cmif_types.h"
+#include "core/hle/service/kernel_helpers.h"
 #include "core/hle/service/service.h"
+#include "core/hle/service/psc/ovln/ovln_types.h"
+
+namespace Kernel {
+class KReadableEvent;
+}
 
 namespace Service::PSC {
 
@@ -11,6 +25,22 @@ class IReceiver final : public ServiceFramework<IReceiver> {
 public:
     explicit IReceiver(Core::System& system_);
     ~IReceiver() override;
+
+    IReceiver(const IReceiver&) = delete;
+    IReceiver& operator=(const IReceiver&) = delete;
+
+private:
+    Result AddSource(SourceName source_name);
+    Result RemoveSource(SourceName source_name);
+    Result GetReceiveEventHandle(OutCopyHandle<Kernel::KReadableEvent> out_event);
+    Result Receive(Out<OverlayNotification> out_notification, Out<MessageFlags> out_flags);
+    Result ReceiveWithTick(Out<OverlayNotification> out_notification, Out<MessageFlags> out_flags,
+                           Out<u64> out_tick);
+
+    KernelHelpers::ServiceContext service_context;
+    Kernel::KEvent* receive_event;
+
+    std::map<std::string, std::vector<std::pair<OverlayNotification, MessageFlags>>> message_sources;
 };
 
 } // namespace Service::PSC

src/core/hle/service/psc/ovln/receiver_service.cpp

@@ -1,3 +1,6 @@
+// SPDX-FileCopyrightText: Copyright 2025 Eden Emulator Project
+// SPDX-License-Identifier: GPL-3.0-or-later
+
 // SPDX-FileCopyrightText: Copyright 2024 yuzu Emulator Project
 // SPDX-License-Identifier: GPL-2.0-or-later
 
@@ -21,7 +24,7 @@ IReceiverService::~IReceiverService() = default;
 
 Result IReceiverService::OpenReceiver(Out<SharedPointer<IReceiver>> out_receiver) {
     LOG_DEBUG(Service_PSC, "called");
-    *out_receiver = std::make_shared<IReceiver>(system);
+    *out_receiver = std::shared_ptr<IReceiver>(new IReceiver(system));
     R_SUCCEED();
 }