FreeRDP/include/freerdp/channels/wtsvc.h
2012-06-26 13:55:49 +08:00

131 lines
4.3 KiB
C

/**
* FreeRDP: A Remote Desktop Protocol client.
* Server Virtual Channel Interface
*
* Copyright 2011-2012 Vic Lee
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/**
* The server-side virtual channel API follows the Microsoft Remote Desktop
* Services API functions WTSVirtualChannel* defined in:
* http://msdn.microsoft.com/en-us/library/windows/desktop/aa383464.aspx
*
* Difference between the MS API are documented in this header. All functions
* are implemented in and integrated with libfreerdp-channels.
*
* Unlike MS API, all functions except WTSVirtualChannelOpenEx in this
* implementation are thread-safe.
*/
#ifndef __FREERDP_WTSVC_H
#define __FREERDP_WTSVC_H
#include <freerdp/types.h>
#include <freerdp/peer.h>
typedef struct WTSVirtualChannelManager WTSVirtualChannelManager;
#define WTS_CHANNEL_OPTION_DYNAMIC 0x00000001
typedef enum _WTS_VIRTUAL_CLASS
{
WTSVirtualClientData,
WTSVirtualFileHandle,
WTSVirtualChannelReady
} WTS_VIRTUAL_CLASS;
/**
* WTSVirtualChannelManager functions are FreeRDP extensions to the API.
*/
FREERDP_API WTSVirtualChannelManager* WTSCreateVirtualChannelManager(freerdp_peer* client);
FREERDP_API void WTSDestroyVirtualChannelManager(WTSVirtualChannelManager* vcm);
FREERDP_API void WTSVirtualChannelManagerGetFileDescriptor(WTSVirtualChannelManager* vcm,
void** fds, int* fds_count);
FREERDP_API boolean WTSVirtualChannelManagerCheckFileDescriptor(WTSVirtualChannelManager* vcm);
/**
* Opens a static or dynamic virtual channel and return the handle. If the
* operation fails, a NULL handle is returned.
*
* The original MS API has 'DWORD SessionId' as the first argument, while we
* use our WTSVirtualChannelManager object instead.
*
* Static virtual channels must be opened from the main thread. Dynamic virtual channels
* can be opened from any thread.
*/
FREERDP_API void* WTSVirtualChannelOpenEx(
/* __in */ WTSVirtualChannelManager* vcm,
/* __in */ const char* pVirtualName,
/* __in */ uint32 flags);
/**
* Returns information about a specified virtual channel.
*
* Servers use this function to gain access to a virtual channel file handle
* that can be used for asynchronous I/O.
*/
FREERDP_API boolean WTSVirtualChannelQuery(
/* __in */ void* hChannelHandle,
/* __in */ WTS_VIRTUAL_CLASS WtsVirtualClass,
/* __out */ void** ppBuffer,
/* __out */ uint32* pBytesReturned);
/**
* Frees memory allocated by WTSVirtualChannelQuery
*/
FREERDP_API void WTSFreeMemory(
/* __in */ void* pMemory);
/**
* Reads data from the server end of a virtual channel.
*
* FreeRDP behavior:
*
* This function will always return a complete channel data packet, i.e. chunks
* are already assembled. If BufferSize argument is smaller than the packet
* size, it will set the desired size in pBytesRead and return false. The
* caller should allocate a large enough buffer and call this function again.
* Returning false with pBytesRead set to zero indicates an error has occurred.
* If no pending packet to be read, it will set pBytesRead to zero and return
* true.
*
* TimeOut is not supported, and this function will always return immediately.
* The caller should use the file handle returned by WTSVirtualChannelQuery to
* determine whether a packet has arrived.
*/
FREERDP_API boolean WTSVirtualChannelRead(
/* __in */ void* hChannelHandle,
/* __in */ uint32 TimeOut,
/* __out */ uint8* Buffer,
/* __in */ uint32 BufferSize,
/* __out */ uint32* pBytesRead);
/**
* Writes data to the server end of a virtual channel.
*/
FREERDP_API boolean WTSVirtualChannelWrite(
/* __in */ void* hChannelHandle,
/* __in */ uint8* Buffer,
/* __in */ uint32 Length,
/* __out */ uint32* pBytesWritten);
/**
* Closes an open virtual channel handle.
*/
FREERDP_API boolean WTSVirtualChannelClose(
/* __in */ void* hChannelHandle);
#endif /* __FREERDP_WTSVC_H */