API Loader Constants

NativePluginKit.Loader.Constants

Shared ABI definitions exchanged between host and plugin.

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HostApiAttribute

[AttributeUsage(AttributeTargets.Field)]
public sealed class HostApiAttribute : Attribute
{
    public string TargetNamespace { get; }
    public string ClassName { get; }
    public string MethodName { get; }
    public Type NativeDelegate { get; }
    public Type? PublicDelegate { get; }

    public HostApiAttribute(string targetNamespace, string className,
        string methodName, Type nativeDelegate, Type? publicDelegate = null);
}

Marks a field in HostApiTable so the source generator produces a public API class. NativeDelegate describes the raw ABI signature (pointer parameters); PublicDelegate describes the ergonomic signature (managed types like string).

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HostApiTable

[StructLayout(LayoutKind.Sequential)]
public struct HostApiTable
{
    // ~70 IntPtr fields, one per generated API method.
}

Do not edit HostApiTable manually — every field carries a [HostApi] attribute that drives code generation. Adding an API is: add field + add attribute + extend HostApiBridgeBuilder.Create + implement the delegate in the host.

Field groups (in order):

Group	Example fields
Infrastructure	FreeString
Scene	TransitionToScene, Scene_GetCurrentScenePath
Logging	PrintLog, PrintWarning, PrintError, LogDebug
Config	Config_GetCharacterImagePath, Config_GetExecutableDirectory, Config_GetPluginsDirectory
Timing	Timing_GetTimeSinceStartup
Events	RegisterEventCallback, UnregisterEventCallback
Story	Story_GetCurrentTimelineName, Story_IsBattle, Story_StartTimeline, Story_EndTimeline, Story_SendSignal
Cards	Card_GetCardCount, Card_GetCardNameAt, ..., Card_GetAppliedEffectParam2
Entities	Entity_GetCount, Entity_GetIdAt, ..., Entity_GetEffectMaxStacks

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HostApiBridgeBuilder

public static unsafe class HostApiBridgeBuilder
{
    public static HostApiTable Create(
        FreeStringDelegate freeString,
        TransitionToSceneDelegate transition,
        GetStringDelegate getCurrentScenePath,
        PrintLogDelegate printLog,
        // ... ~70 parameters
        );

    // Delegates are nested types (TransitionToSceneDelegate, PrintLogDelegate, ...)
}

Static factory that converts managed delegates to unmanaged function pointers and fills a HostApiTable.

Lifetime: the builder keeps strong references to every delegate it receives, so callers do not need to keep them alive separately.

Delegates use bool return values where the ergonomic API returns bool (e.g. RegisterEventDelegate), and int return values for C-ABI-safe enums.

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PluginInfo

[StructLayout(LayoutKind.Sequential)]
public struct PluginInfo
{
    public IntPtr NamePtr;
    public IntPtr DescriptionPtr;
    public IntPtr AuthorPtr;
    public int MajorVersion, MinorVersion, BuildVersion, RevisionVersion;
    public int RequiredApiMajor, RequiredApiMinor;

    public string  GetName();
    public string  GetDescription();
    public string  GetAuthor();
    public Version GetVersion();
    public Version GetRequiredApiVersion();
}

Metadata blob returned by the plugin's GetPluginInfo export. Strings are UTF-8 pointers allocated with StringToCoTaskMemUTF8 and remain valid for the lifetime of the plugin.

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PluginInitDelegate

[UnmanagedFunctionPointer(CallingConvention.Cdecl)]
public delegate void PluginInitDelegate(IntPtr hostApiTable);

Matches the plugin's OnInit export.