kernel: process: Implement GetFreeThreadCount

Used by Just Dance® 2023 Edition

src/core/hle/kernel/k_process.cpp

@@ -285,6 +285,17 @@ void KProcess::UnregisterThread(KThread* thread) {
     thread_list.remove(thread);
 }
 
+u64 KProcess::GetFreeThreadCount() const {
+    if (resource_limit != nullptr) {
+        const auto current_value =
+            resource_limit->GetCurrentValue(LimitableResource::ThreadCountMax);
+        const auto limit_value = resource_limit->GetLimitValue(LimitableResource::ThreadCountMax);
+        return limit_value - current_value;
+    } else {
+        return 0;
+    }
+}
+
 Result KProcess::Reset() {
     // Lock the process and the scheduler.
     KScopedLightLock lk(state_lock);

src/core/hle/kernel/k_process.h

@@ -304,6 +304,9 @@ public:
     /// from this process' thread list.
     void UnregisterThread(KThread* thread);
 
+    /// Retrieves the number of available threads for this process.
+    u64 GetFreeThreadCount() const;
+
     /// Clears the signaled state of the process if and only if it's signaled.
     ///
     /// @pre The process must not be already terminated. If this is called on a

src/core/hle/kernel/svc.cpp

@@ -815,8 +815,15 @@ static Result GetInfo(Core::System& system, u64* result, u64 info_id, Handle han
         // 6.0.0+
         TotalPhysicalMemoryAvailableWithoutSystemResource = 21,
         TotalPhysicalMemoryUsedWithoutSystemResource = 22,
+        // 10.0.0+
+        IsApplication = 23,
+        // 13.0.0+
+        FreeThreadCount = 24,
+        // 14.0.0+
+        IsSvcPermitted = 26,
 
         // Homebrew only
+        MesosphereMeta = 65000,
         MesosphereCurrentProcess = 65001,
     };
 
@@ -840,7 +847,9 @@ static Result GetInfo(Core::System& system, u64* result, u64 info_id, Handle han
     case GetInfoType::TitleId:
     case GetInfoType::UserExceptionContextAddr:
     case GetInfoType::TotalPhysicalMemoryAvailableWithoutSystemResource:
-    case GetInfoType::TotalPhysicalMemoryUsedWithoutSystemResource: {
+    case GetInfoType::TotalPhysicalMemoryUsedWithoutSystemResource:
+    case GetInfoType::IsApplication:
+    case GetInfoType::FreeThreadCount: {
         if (info_sub_id != 0) {
             LOG_ERROR(Kernel_SVC, "Info sub id is non zero! info_id={}, info_sub_id={}", info_id,
                       info_sub_id);
@@ -929,6 +938,10 @@ static Result GetInfo(Core::System& system, u64* result, u64 info_id, Handle han
             *result = process->GetTotalPhysicalMemoryUsedWithoutSystemResource();
             return ResultSuccess;
 
+        case GetInfoType::FreeThreadCount:
+            *result = process->GetFreeThreadCount();
+            return ResultSuccess;
+
         default:
             break;
         }