HGScannerLib增加获取设备状态的接口

build/windows/HGScannerLib/HGScannerLib.def

@@ -22,6 +22,7 @@ HGLib_ReleaseDeviceParamGroupList
 HGLib_ReleaseDeviceParam
 HGLib_ResetDeviceParam
 HGLib_DeviceIsPaperOn
+HGLib_GetDeviceStatus
 HGLib_DeviceRestart
 HGLib_DeviceShutDown
 HGLib_StartDeviceScan

sdk/scannerlib/HGLibDeviceImpl.cpp

@@ -948,6 +948,16 @@ HGBool HGLibDeviceImpl::IsPaperOn()
 	return HGFALSE;
 }
 
+HGInt HGLibDeviceImpl::GetStatus()
+{
+	SANE_Bool isOn = SANE_FALSE;
+	unsigned int len = sizeof(SANE_Bool);
+	SANE_Status status = sane_io_control(m_devHandle, IO_CTRL_CODE_GET_PAPER_ON, &isOn, &len);
+	if (SANE_STATUS_GOOD == status)
+		return isOn ? 1 : 0;
+	return -1;
+}
+
 HGBool HGLibDeviceImpl::Restart()
 {
 	SANE_Power stat = SANE_POWER_RESTART;

sdk/scannerlib/HGLibDeviceImpl.hpp

@@ -32,6 +32,7 @@ public:
 	static HGBool ReleaseParam(HGLibDeviceParam* param);
 	HGBool ResetParam();
 	HGBool IsPaperOn();
+	HGInt GetStatus();
 	HGBool Restart();
 	HGBool ShutDown();
 	HGBool StartScan(HGLibDeviceScanEventFunc eventFunc, HGPointer eventParam,

sdk/scannerlib/HGScannerLib.cpp

@@ -252,6 +252,17 @@ HGBool HGAPI HGLib_DeviceIsPaperOn(HGLibDevice device)
 	return deviceImpl->IsPaperOn();
 }
 
+HGInt HGAPI HGLib_GetDeviceStatus(HGLibDevice device)
+{
+	if (NULL == device)
+	{
+		return -1;
+	}
+
+	HGLibDeviceImpl* deviceImpl = (HGLibDeviceImpl*)device;
+	return deviceImpl->GetStatus();
+}
+
 HGBool HGAPI HGLib_DeviceRestart(HGLibDevice device)
 {
 	if (NULL == device)

sdk/scannerlib/HGScannerLib.h

@@ -527,6 +527,9 @@ HGEXPORT HGBool HGAPI HGLib_ResetDeviceParam(HGLibDevice device);
 /* 设备是否有纸 */
 HGEXPORT HGBool HGAPI HGLib_DeviceIsPaperOn(HGLibDevice device);
 
+/* 获取设备状态, -1表示异常，0表示无纸，1表示有纸 */
+HGEXPORT HGInt HGAPI HGLib_GetDeviceStatus(HGLibDevice device);
+
 /* 重启设备 */
 HGEXPORT HGBool HGAPI HGLib_DeviceRestart(HGLibDevice device);