Add String Support to IPC Push/Pop

This commit does some minor renaming/reordering in IPC and adds support for strings to IPC Push/Pop. It also fixes a tiny regression with the frametime display.

app/src/main/cpp/skyline/gpu.cpp

@@ -62,7 +62,7 @@ namespace skyline::gpu {
             if (frameTimestamp) {
                 auto now = util::GetTimeNs();
 
-                frametime = static_cast<u32>((now - frameTimestamp) / (constant::NsInSecond / 100)); // frametime / 100 is the real ms value, this is to retain the first two decimals
+                frametime = static_cast<u32>((now - frameTimestamp) / 10000); // frametime / 100 is the real ms value, this is to retain the first two decimals
                 fps = static_cast<u16>(constant::NsInSecond / (now - frameTimestamp));
 
                 frameTimestamp = now;

app/src/main/cpp/skyline/kernel/ipc.cpp

@@ -143,7 +143,7 @@ namespace skyline::kernel::ipc {
         memset(tls, 0, constant::TlsIpcSize);
 
         auto header = reinterpret_cast<CommandHeader *>(pointer);
-        header->rawSize = static_cast<u32>((sizeof(PayloadHeader) + argVec.size() + (domainObjects.size() * sizeof(KHandle)) + constant::IpcPaddingSum + (isDomain ? sizeof(DomainHeaderRequest) : 0)) / sizeof(u32)); // Size is in 32-bit units because Nintendo
+        header->rawSize = static_cast<u32>((sizeof(PayloadHeader) + payload.size() + (domainObjects.size() * sizeof(KHandle)) + constant::IpcPaddingSum + (isDomain ? sizeof(DomainHeaderRequest) : 0)) / sizeof(u32)); // Size is in 32-bit units because Nintendo
         header->handleDesc = (!copyHandles.empty() || !moveHandles.empty());
         pointer += sizeof(CommandHeader);
 
@@ -174,15 +174,15 @@ namespace skyline::kernel::ipc {
             pointer += sizeof(DomainHeaderResponse);
         }
 
-        auto payload = reinterpret_cast<PayloadHeader *>(pointer);
+        auto payloadHeader = reinterpret_cast<PayloadHeader *>(pointer);
-        payload->magic = util::MakeMagic<u32>("SFCO"); // SFCO is the magic in IPC responses
+        payloadHeader->magic = util::MakeMagic<u32>("SFCO"); // SFCO is the magic in IPC responses
-        payload->version = 1;
+        payloadHeader->version = 1;
-        payload->value = errorCode;
+        payloadHeader->value = errorCode;
         pointer += sizeof(PayloadHeader);
 
-        if (!argVec.empty())
+        if (!payload.empty())
-            std::memcpy(pointer, argVec.data(), argVec.size());
+            std::memcpy(pointer, payload.data(), payload.size());
-        pointer += argVec.size();
+        pointer += payload.size();
 
         if (isDomain) {
             for (auto &domainObject : domainObjects) {
@@ -191,6 +191,6 @@ namespace skyline::kernel::ipc {
             }
         }
 
-        state.logger->Debug("Output: Raw Size: {}, Command ID: 0x{:X}, Copy Handles: {}, Move Handles: {}", u32(header->rawSize), u32(payload->value), copyHandles.size(), moveHandles.size());
+        state.logger->Debug("Output: Raw Size: {}, Command ID: 0x{:X}, Copy Handles: {}, Move Handles: {}", u32(header->rawSize), u32(payloadHeader->value), copyHandles.size(), moveHandles.size());
     }
 }

app/src/main/cpp/skyline/kernel/ipc.h

@@ -281,6 +281,16 @@ namespace skyline {
                 return value;
             }
 
+            /**
+             * @brief This returns a std::string_view from the payload
+             * @param size The length of the string (0 means the string is null terminated)
+             */
+            inline std::string_view PopString(size_t size = 0) {
+                auto view = size ? std::string_view(reinterpret_cast<const char*>(payloadOffset), size) : std::string_view(reinterpret_cast<const char*>(payloadOffset));
+                payloadOffset += view.length();
+                return view;
+            }
+
             /**
              * @brief This skips an object to pop off the top
              * @tparam ValueType The type of the object to skip
@@ -296,8 +306,8 @@ namespace skyline {
          */
         class IpcResponse {
           private:
-            std::vector<u8> argVec; //!< This holds all of the contents to be pushed to the payload
             const DeviceState &state; //!< The state of the device
+            std::vector<u8> payload; //!< This holds all of the contents to be pushed to the payload
 
           public:
             bool nWrite{}; //!< This is to signal the IPC handler to not write this, as it will be manually written
@@ -320,12 +330,22 @@ namespace skyline {
              */
             template<typename ValueType>
             inline void Push(const ValueType &value) {
-                argVec.reserve(argVec.size() + sizeof(ValueType));
+                auto size = payload.size();
-                auto item = reinterpret_cast<const u8 *>(&value);
+                payload.resize(size + sizeof(ValueType));
-                for (uint index = 0; sizeof(ValueType) > index; index++) {
+
-                    argVec.push_back(*item);
+                std::memcpy(payload.data() + size, reinterpret_cast<const u8 *>(&value), sizeof(ValueType));
-                    item++;
             }
+
+            /**
+             * @brief Writes a string to the payload
+             * @param string The string to write to the payload
+             */
+            template<>
+            inline void Push(const std::string &string) {
+                auto size = payload.size();
+                payload.resize(size + string.size());
+
+                std::memcpy(payload.data() + size, string.data(), string.size());
             }
 
             /**

app/src/main/cpp/skyline/services/sm/IUserInterface.cpp

@@ -12,7 +12,7 @@ namespace skyline::service::sm {
     void IUserInterface::Initialize(type::KSession &session, ipc::IpcRequest &request, ipc::IpcResponse &response) {}
 
     void IUserInterface::GetService(type::KSession &session, ipc::IpcRequest &request, ipc::IpcResponse &response) {
-        std::string serviceName(reinterpret_cast<char *>(request.cmdArg));
+        std::string serviceName(request.PopString());
 
         if (serviceName.empty()) {
             response.errorCode = constant::status::ServiceInvName;

app/src/main/cpp/skyline/services/visrv/IApplicationDisplayService.cpp

@@ -41,7 +41,7 @@ namespace skyline::service::visrv {
     }
 
     void IApplicationDisplayService::OpenDisplay(type::KSession &session, ipc::IpcRequest &request, ipc::IpcResponse &response) {
-        std::string displayName(reinterpret_cast<char *>(request.cmdArg));
+        std::string displayName(request.PopString());
         state.logger->Debug("Setting display as: {}", displayName);
         state.os->serviceManager.GetService<hosbinder::IHOSBinderDriver>(Service::hosbinder_IHOSBinderDriver)->SetDisplay(displayName);