luabridge: implement MultiWrite

snes/luabridge/memory.go

@@ -74,6 +74,55 @@ func (d *Device) MultiReadMemory(ctx context.Context, reads ...snes.MemoryReadRe
 	return
 }
 
-func (d *Device) MultiWriteMemory(ctx context.Context, writes ...snes.MemoryWriteRequest) ([]snes.MemoryWriteResponse, error) {
-	panic("implement me")
+func (d *Device) MultiWriteMemory(ctx context.Context, writes ...snes.MemoryWriteRequest) (rsp []snes.MemoryWriteResponse, err error) {
+	defer func() {
+		if err != nil {
+			rsp = nil
+			closeErr := d.Close()
+			if closeErr != nil {
+				log.Printf("luabridge: close error: %v\n", closeErr)
+			}
+		}
+	}()
+
+	deadline, ok := ctx.Deadline()
+	if !ok {
+		deadline = time.Now().Add(readWriteTimeout)
+	}
+
+	rsp = make([]snes.MemoryWriteResponse, len(writes))
+	for j, write := range writes {
+		addr := mapping.TranslateAddress(
+			write.RequestAddress,
+			write.RequestAddressSpace,
+			d.Mapping,
+			sni.AddressSpace_SnesABus,
+		)
+
+		// preallocate enough space to write the whole command:
+		sb := bytes.NewBuffer(make([]byte, 0, 24 + 4*len(write.Data)))
+		_, _ = fmt.Fprintf(sb, "Write|%d", addr)
+		for _, b := range write.Data {
+			_, _ = fmt.Fprintf(sb, "|%d", b)
+		}
+		sb.WriteByte('\n')
+
+		// send the command:
+		var n int
+		n, err = d.WriteDeadline(sb.Bytes(), deadline)
+		if err != nil {
+			return
+		}
+		_ = n
+
+		rsp[j] = snes.MemoryWriteResponse{
+			RequestAddress:      write.RequestAddress,
+			RequestAddressSpace: write.RequestAddressSpace,
+			DeviceAddress:       addr,
+			DeviceAddressSpace:  sni.AddressSpace_SnesABus,
+			Size:                len(write.Data),
+		}
+	}
+
+	return
 }