new plugin system

2026-03-19 16:29:26 -05:00
parent 2aeac06b1a
commit cf314b5189
31 changed files with 1942 additions and 517 deletions
@@ -0,0 +1,138 @@
+//go:build windows
+
+package plugins
+
+import (
+	"errors"
+	"fmt"
+	"sync"
+	"syscall"
+	"unsafe"
+)
+
+func loadNativePlugin(data []byte) (NativePlugin, error) {
+	if len(data) == 0 {
+		return nil, errors.New("empty plugin binary")
+	}
+
+	mm, err := LoadMemoryModule(data)
+	if err != nil {
+		return nil, fmt.Errorf("pe load: %w", err)
+	}
+
+	if err := mm.CallEntryPoint(dllProcessAttach); err != nil {
+		mm.Free()
+		return nil, fmt.Errorf("DllMain init: %w", err)
+	}
+
+	onLoad, err := mm.GetExport("PluginOnLoad")
+	if err != nil {
+		mm.Free()
+		return nil, err
+	}
+	onEvent, err := mm.GetExport("PluginOnEvent")
+	if err != nil {
+		mm.Free()
+		return nil, err
+	}
+	onUnload, err := mm.GetExport("PluginOnUnload")
+	if err != nil {
+		mm.Free()
+		return nil, err
+	}
+
+	setCallback, _ := mm.GetExport("PluginSetCallback")
+
+	dp := &dllPlugin{
+		mem:             mm,
+		onLoadAddr:      onLoad,
+		onEventAddr:     onEvent,
+		onUnloadAddr:    onUnload,
+		setCallbackAddr: setCallback,
+	}
+	return dp, nil
+}
+
+type dllPlugin struct {
+	mem             *MemoryModule
+	onLoadAddr      uintptr
+	onEventAddr     uintptr
+	onUnloadAddr    uintptr
+	setCallbackAddr uintptr
+	callbackHandle  uintptr // prevent GC of the callback closure
+	mu              sync.Mutex
+}
+
+func (p *dllPlugin) Load(send func(string, []byte), hostInfo []byte) error {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+
+	// Create a stdcall callback the DLL can invoke to send events to the host.
+	cb := syscall.NewCallback(func(eventPtr, eventLen, payloadPtr, payloadLen uintptr) uintptr {
+		event := make([]byte, eventLen)
+		if eventLen > 0 {
+			copy(event, unsafe.Slice((*byte)(unsafe.Pointer(eventPtr)), eventLen))
+		}
+		payload := make([]byte, payloadLen)
+		if payloadLen > 0 {
+			copy(payload, unsafe.Slice((*byte)(unsafe.Pointer(payloadPtr)), payloadLen))
+		}
+		send(string(event), payload)
+		return 0
+	})
+	p.callbackHandle = cb
+
+	if p.setCallbackAddr != 0 {
+		syscall.SyscallN(p.setCallbackAddr, cb)
+	}
+
+	var infoPtr uintptr
+	infoLen := uintptr(len(hostInfo))
+	if len(hostInfo) > 0 {
+		infoPtr = uintptr(unsafe.Pointer(&hostInfo[0]))
+	}
+	ret, _, _ := syscall.SyscallN(p.onLoadAddr, infoPtr, infoLen, cb)
+	if int32(ret) != 0 {
+		return errors.New("PluginOnLoad returned non-zero")
+	}
+	return nil
+}
+
+func (p *dllPlugin) Event(event string, payload []byte) error {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+
+	eventBytes := []byte(event)
+	var eventPtr, payloadPtr uintptr
+	eventLen := uintptr(len(eventBytes))
+	payloadLen := uintptr(len(payload))
+	if len(eventBytes) > 0 {
+		eventPtr = uintptr(unsafe.Pointer(&eventBytes[0]))
+	}
+	if len(payload) > 0 {
+		payloadPtr = uintptr(unsafe.Pointer(&payload[0]))
+	}
+
+	ret, _, _ := syscall.SyscallN(p.onEventAddr, eventPtr, eventLen, payloadPtr, payloadLen)
+	if int32(ret) != 0 {
+		return errors.New("PluginOnEvent returned non-zero")
+	}
+	return nil
+}
+
+func (p *dllPlugin) Unload() {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	if p.onUnloadAddr != 0 {
+		syscall.SyscallN(p.onUnloadAddr)
+	}
+}
+
+func (p *dllPlugin) Close() error {
+	p.Unload()
+	if p.mem != nil {
+		p.mem.Free()
+		p.mem = nil
+	}
+	return nil
+}