LDicomNet::SendCCancelRequest (original) (raw)
Summary
Sends a C-CANCEL-REQ message to a peer member of a connection. This function is available in the PACS Imaging Toolkit.
Syntax
#include "ltdic.h"
L_INT LDicomNet::SendCCancelRequest(nPresentationID, nMessageID)
Parameters
L_UCHAR nPresentationID
Presentation ID. The presentation ID provides information about both the class type of the data and the transfer syntax to use when transferring the data.
L_UINT16 nMessageID
Message ID. Each message sent by a member of a connection should have a unique ID. Since a member of a connection may send several messages, this ID allows that member to identify when a specific request has been completed.
Returns
| Value | Meaning |
|---|---|
| 0 | SUCCESS |
| >0 | An error occurred. Refer to Return Codes. |
Comments
Calling this function generates a call to LDicomNet::OnReceiveCCancelRequest on the SCP.
Required DLLs and Libraries
- LTDIC
- For a listing of the exact DLLs and Libraries needed, based on the toolkit version, refer to Files To Be Included With Your Application
Platforms
Win32, x64
See Also
Functions
Topics
Example
This is a basic, but complete example that shows a DICOM client sending a C-Cancel-REQ to a server to cancel the last request (a C-Echo-REQ), and the server processing the request.
namespace LDicomNet_SendCCancelRequest_Namespace
{
// Logs a message
// This implementation logs to the console, and the debug window
L_VOID LogMessage(TCHAR *szMsg)
{
wprintf(TEXT("\n"));
wprintf(szMsg);
OutputDebugStringW(TEXT("\n"));
OutputDebugStringW(szMsg);
}
L_VOID LogMessage(TCHAR *s, L_INT n)
{
TCHAR szLog[200] = {0};
wsprintf(szLog, TEXT("%s [%d]"), s, n);
LogMessage(szLog);
}
// *******************************************************************************************
// Client Class
//
// Class that is used to connect to the server
// *******************************************************************************************
class CMyClient : public LDicomNet
{
public:
CMyClient(L_INT32 nMode): LDicomNet(NULL, nMode)
{
m_waitEvent = CreateEvent( NULL, TRUE, TRUE, TEXT("ClientEvent"));
ResetEvent(m_waitEvent);
}
~CMyClient(void)
{
CloseHandle(m_waitEvent);
}
// Client
L_VOID OnConnect (L_INT nError);
L_VOID OnReceiveAssociateAccept (LDicomAssociate *pPDU);
L_VOID OnReceiveReleaseResponse ();
L_VOID OnReceiveCEchoResponse (L_UCHAR nPresentationID, L_UINT16 nMessageID, L_TCHAR *pszClass, L_UINT16 nStatus);
L_BOOL Wait(DWORD timeout = 5000);
private:
HANDLE m_waitEvent;
};
// Continues dispatching messages until hEvent is signalled, our timeout
// Returns TRUE if hEvent is signalled
// Returns FALSE if timeout
L_BOOL MessageLoop (
HANDLE hEvent, // handles that need to be waited on
DWORD timeout // timeout in milliseconds
)
{
DWORD dwStart = GetTickCount();
MSG msg = {0};
volatile L_BOOL bRunForever = TRUE;
while (bRunForever)
{
if (PeekMessage(&msg, NULL, 0, 0, PM_REMOVE))
{
TranslateMessage(&msg);
DispatchMessage(&msg);
}
if (WaitForSingleObject(hEvent, 0) == WAIT_OBJECT_0)
{
ResetEvent(hEvent);
return TRUE;
}
DWORD dwCurrent = GetTickCount();
if ((dwCurrent - dwStart) > timeout)
{
return FALSE;
}
}
return TRUE;
}
L_VOID CMyClient::OnConnect(L_INT nError)
{
L_TCHAR szMsg[200] = {0};
wsprintf(szMsg, TEXT("CMyClient::OnConnect: nError[%d]"), nError);
LogMessage(szMsg);
}
L_VOID CMyClient::OnReceiveAssociateAccept (LDicomAssociate *pPDU)
{
UNREFERENCED_PARAMETER(pPDU);
SetEvent(m_waitEvent);
LogMessage(TEXT("CMyClient::OnReceiveAssociateAccept"));
}
L_VOID CMyClient::OnReceiveCEchoResponse(L_UCHAR nPresentationID, L_UINT16 nMessageID, L_TCHAR *pszClass, L_UINT16 nStatus)
{
SetEvent(m_waitEvent);
L_TCHAR szMsg[200] = {0};
if (pszClass == NULL)
{
pszClass = TEXT("");
}
wsprintf(szMsg, TEXT("CMyClient::OnReceiveCEchoResponse: \n\tnPresentationID[%d], \n\tnMessageID[%d], \n\tpszClass[%s], \n\tnStatus[%d]"), nPresentationID, nMessageID, pszClass, nStatus);
LogMessage(szMsg);
}
L_VOID CMyClient::OnReceiveReleaseResponse()
{
SetEvent(m_waitEvent);
LogMessage(TEXT("CMyClient::OnReceiveReleaseResponse"));
}
L_BOOL CMyClient::Wait(DWORD timeout)
{
L_BOOL bRet = MessageLoop(m_waitEvent, timeout);
return bRet;
}
// *******************************************************************************************
// Server Connection Class
//
// When a client connects, CMyServer creates a new instance of the CMyServerConnection class
// and accepts the connection.
// *******************************************************************************************
class CMyServerConnection : public LDicomNet
{
public:
CMyServerConnection(L_INT32 nMode): LDicomNet(NULL, nMode)
{
}
~CMyServerConnection(void)
{
}
// Server
L_VOID OnReceiveAssociateRequest(LDicomAssociate *pPDU);
L_VOID OnReceiveAssociateReject(L_UCHAR nResult, L_UCHAR nSource, L_UCHAR nReason);
L_VOID OnReceiveCEchoRequest(L_UCHAR nPresentationID, L_UINT16 nMessageID, L_TCHAR *pszClass);
L_VOID OnReceiveCCancelRequest(L_UCHAR nPresentationID, L_UINT16 nMessageID);
L_VOID OnReceiveReleaseRequest();
};
#define SIZEINWORD(p) sizeof(p)/sizeof(L_TCHAR)
L_VOID CMyServerConnection::OnReceiveAssociateRequest(LDicomAssociate *pPDU)
{
LogMessage(TEXT("\tCMyServerConnection::OnReceiveAssociateRequest"));
//check the version, if not 1, reject it
if (pPDU->GetVersion() != 1)
{
LogMessage(TEXT("\tCMyServerConnection::SendAssociateReject"));
SendAssociateReject(
PDU_REJECT_RESULT_PERMANENT,
PDU_REJECT_SOURCE_USER,
PDU_REJECT_REASON_UNKNOWN
);
}
else
{
LDicomAssociate DicomAssociate(FALSE);
L_TCHAR clientAE[20] = {0};
pPDU->GetCalling(clientAE, 20);
if (lstrcmp(clientAE, TEXT("LEAD_CLIENT")) != 0)
{
LogMessage(TEXT("\tCMyServerConnection::SendAssociateReject"));
SendAssociateReject(
PDU_REJECT_RESULT_PERMANENT,
PDU_REJECT_SOURCE_USER,
PDU_REJECT_REASON_UNKNOWN
);
return;
}
//Copy presentation objects from received
//Reply that we only support the first Transfer Syntax from the received hPDU
L_TCHAR szTransfer[PDU_MAX_UID_SIZE+1] = {0};
L_TCHAR szAbstract[PDU_MAX_UID_SIZE+1] = {0};
L_INT iPresentationCount = pPDU->GetPresentationCount();
for (L_UCHAR i = 0; i<iPresentationCount; i++)
{
L_UCHAR nId = pPDU->GetPresentation(i);
pPDU->GetTransfer(nId, 0, szTransfer, PDU_MAX_UID_SIZE+1);
L_UCHAR nResult = PDU_ACCEPT_RESULT_SUCCESS;
pPDU->GetAbstract(nId, szAbstract, PDU_MAX_UID_SIZE+1);
DicomAssociate.AddPresentation( nId, nResult, szAbstract);
DicomAssociate.AddTransfer( nId, szTransfer);
}
LogMessage(TEXT("\tCMyServerConnection::SendAssociateAccept"));
SendAssociateAccept(&DicomAssociate);
}
}
L_VOID CMyServerConnection::OnReceiveAssociateReject(L_UCHAR nResult, L_UCHAR nSource, L_UCHAR nReason)
{
L_TCHAR szMsg[200] = {0};
wsprintf(szMsg, TEXT("\tOnReceiveAssociateReject\nResult[%d]\nSource[%d]\nReason[%d]"), nResult, nSource, nReason);
LogMessage(szMsg);
}
L_VOID CMyServerConnection::OnReceiveCEchoRequest(L_UCHAR nPresentationID, L_UINT16 nMessageID, L_TCHAR *pszClass)
{
LogMessage(TEXT("\tCMyServerConnection::OnReceiveCEchoRequest"));
LogMessage(TEXT("\tCMyServerConnection::SendCEchoResponse"));
SendCEchoResponse(nPresentationID, nMessageID, pszClass, COMMAND_STATUS_SUCCESS);
}
L_VOID CMyServerConnection::OnReceiveCCancelRequest(L_UCHAR nPresentationID, L_UINT16 nMessageID)
{
LogMessage(TEXT("\tCMyServerConnection::OnReceiveCCancelRequest"));
LogMessage(TEXT("\t\t nPresentationID"), nPresentationID);
LogMessage(TEXT("\t\t nMessageID"), nMessageID);
LogMessage(TEXT("\t\tCancel the last request (in this case a C-Echo-REQ)"));
}
L_VOID CMyServerConnection::OnReceiveReleaseRequest()
{
LogMessage(TEXT("\tCMyServerConnection::OnReceiveReleaseRequest"));
LogMessage(TEXT("\tCMyServerConnection::SendReleaseResponse"));
SendReleaseResponse();
}
// *******************************************************************************************
// Server Class
//
// Listens for connections
// When a client connects, this class creates a CMyServerConnection and accepts the connection
// *******************************************************************************************
class CMyServer : public LDicomNet
{
public:
CMyServer(L_INT32 nMode): LDicomNet(NULL, nMode)
{
m_pServerConnection = NULL;
}
~CMyServer(void)
{
if (m_pServerConnection != NULL)
{
delete m_pServerConnection;
}
}
L_VOID OnAccept (L_INT nError);
L_VOID OnClose (L_INT nError, LDicomNet *pServerConnection);
CMyServerConnection *m_pServerConnection;
};
L_VOID CMyServer::OnAccept(L_INT nError)
{
LogMessage(TEXT("\tCMyServer::OnAccept"));
if (nError != DICOM_SUCCESS)
{
return;
}
if (m_pServerConnection != NULL)
{
delete m_pServerConnection;
m_pServerConnection = NULL;
}
m_pServerConnection = new CMyServerConnection(DICOM_SECURE_NONE);
if (m_pServerConnection == NULL)
{
return;
}
nError = LDicomNet::Accept(m_pServerConnection);
if (nError != DICOM_SUCCESS)
{
delete m_pServerConnection;
return;
}
}
L_VOID CMyServer::OnClose(L_INT nError, LDicomNet *pServerConnection)
{
UNREFERENCED_PARAMETER(nError);
LogMessage(TEXT("\tCMyServer::OnClose"));
if (m_pServerConnection == pServerConnection)
{
m_pServerConnection = NULL;
}
delete (CMyServerConnection *)pServerConnection;
}
// *******************************************************************************************
// Sample starts here
// *******************************************************************************************
#define WaitForProcessing() \
{ \
if (!client.Wait()) \
{ \
LogMessage(TEXT("Timeout: client.Connect")); \
nRet = DICOM_ERROR_NET_TIME_OUT; \
goto Cleanup; \
} \
}
L_INT LDicomNet_SendCCancelRequestExample()
{
LogMessage(TEXT("\n\n *** SendCCancelRequestExample ***"));
L_TCHAR *pszServerAddress = TEXT("127.0.0.1");
L_UINT uServerPort = 105;
L_INT nRet = DICOM_SUCCESS;
LDicomNet::StartUp();
CMyClient client(DICOM_SECURE_NONE);
CMyServer server(DICOM_SECURE_NONE);
LogMessage(TEXT("\tCMyServer::Listen"));
nRet = server.Listen(pszServerAddress, uServerPort, 5);
LogMessage(TEXT("CMyClient::Connect"));
client.Connect(NULL, 0, pszServerAddress, uServerPort);
if (!client.Wait(2000))
{
if (!client.IsConnected())
{
LogMessage(TEXT("Timeout: client.Connect"));
nRet = DICOM_ERROR_NET_TIME_OUT;
goto Cleanup;
}
}
if (nRet == DICOM_SUCCESS)
{
//create the Associate Class as Request
LDicomAssociate dicomAssociateRequest(TRUE);
dicomAssociateRequest.Default();
// Send A-Associate-RQ message
dicomAssociateRequest.SetCalled(TEXT("LEAD_SERVER"));
dicomAssociateRequest.SetCalling(TEXT("LEAD_CLIENT"));
LogMessage(TEXT("CMyClient::SendAssociateRequest"));
nRet = client.SendAssociateRequest(&dicomAssociateRequest);
if (!client.Wait(5000))
{
LogMessage(TEXT("Timeout: client.Connect"));
nRet = DICOM_ERROR_NET_TIME_OUT;
goto Cleanup;
}
}
L_UCHAR nPresentationID = client.GetAssociate()->FindAbstract(UID_VERIFICATION_CLASS);
L_UINT16 uUniqueID = 99;
LogMessage(TEXT("CMyClient::SendCEchoRequest"));
client.SendCEchoRequest( nPresentationID, uUniqueID, UID_VERIFICATION_CLASS);
WaitForProcessing();
LogMessage(TEXT("CMyClient::SendCCancelRequest"));
client.SendCCancelRequest( nPresentationID, uUniqueID);
client.Wait(1000);
LogMessage(TEXT("CMyClient::SendReleaseRequest"));
client.SendReleaseRequest();
WaitForProcessing();
Cleanup:
LogMessage(TEXT("CMyClient::Close"));
client.Close();
client.Wait(1000);
LogMessage(TEXT("\tCMyServer::Close"));
server.Close();
LDicomNet::ShutDown();
return nRet;
}
}