windows-nt/Source/XPSP1/NT/termsrv/remdsk/rds/t120/mst120/userchnl.cpp

319 lines
8.3 KiB
C++
Raw Permalink Normal View History

2020-09-26 03:20:57 -05:00
#include "precomp.h"
#include "fsdiag.h"
DEBUG_FILEZONE(ZONE_T120_MCSNC);
/*
* userchnl.cpp
*
* Copyright (c) 1993 - 1995 by DataBeam Corporation, Lexington, KY
*
* Abstract:
* This is the implementation file for the UserChannel class. It contains
* the code that distinguishes this class from that of its parent, Channel.
*
* The main difference between this class and that of its parent is how
* the join and data requests are handled. There is also a new instance
* variable that keeps track of what attachment leads to the user being
* represented by this class. Merge requests are also generated as is
* appropriate for a user channel
*
* The data primitives are overridden, allowing this object to decide
* not to send data upward, if it is known that the user lies in the
* sub-tree of this provider.
*
* Private Instance Variables:
* m_pUserAttachment
* This is a pointer to the attachment that leads to the user being
* represented by this object.
*
* Private Member Functions:
* None.
*
* Caveats:
* None.
*
* Author:
* James P. Galvin, Jr.
*/
/*
* External Interfaces
*/
#include "userchnl.h"
/*
* UserChannel ()
*
* Public
*
* Functional Description:
* This is the primary constructor for UserChannel objects. It creates
* an object with all instance variable initialized, but with no
* attachments (i.e. the user is not joined to the channel automatically).
*
* Note that most instance variable initialization is done by invoking the
* equivalent constructor in the base class.
*
* Upon successful completion, an attach user confirm is automtically
* issued to the new user.
*/
UserChannel::UserChannel (
ChannelID channel_id,
CAttachment *user_attachment,
PDomain local_provider,
PConnection top_provider,
CChannelList2 *channel_list,
CAttachmentList *attachment_list)
:
Channel(channel_id, local_provider, top_provider, channel_list, attachment_list),
m_pUserAttachment(user_attachment)
{
/*
* Issue an attach user confirm to the new user.
*/
m_pUserAttachment->AttachUserConfirm(RESULT_SUCCESSFUL, channel_id);
}
/*
* UserChannel ()
*
* Public
*
* Functional Description:
* This is a secondary constructor that is only used during merge
* operations. The intent of this constructor is to create an equivalent
* object without issuing any of the confirms.
*
* Note that the additional constructor allows for the creator to specify
* that the user is to be already joined to the channel upon creation.
* The value of user_attachment and attachment should either be the same
* or attachment should be NULL.
*/
UserChannel::UserChannel (
ChannelID channel_id,
CAttachment *user_attachment,
PDomain local_provider,
PConnection top_provider,
CChannelList2 *channel_list,
CAttachmentList *attachment_list,
PConnection pConn)
:
Channel(channel_id, local_provider, top_provider, channel_list, attachment_list, pConn),
m_pUserAttachment(user_attachment)
{
}
/*
* ~UserChannel ()
*
* Public
*
* Functional Description:
* This destructor does nothing more than clear the joined attachment list.
* This is important because it prevents the base class destructor from
* trying to issue channel leave indications to the user if the user is
* locally attached.
*/
UserChannel::~UserChannel ()
{
}
/*
* Channel_Type GetChannelType ()
*
* Public
*
* Functional Description:
* Objects of this class are always user channels, so simply return
* USER_CHANNEL.
*/
Channel_Type UserChannel::GetChannelType ()
{
return (USER_CHANNEL);
}
/*
* BOOL IsValid ()
*
* Public
*
* Functional Description:
* User ID channels are always valid, so return TRUE.
*/
BOOL UserChannel::IsValid ()
{
return (TRUE);
}
/*
* CAttachment *GetAttachment ()
*
* Public
*
* Functional Description:
* Return the pointer to the attachment leading to the user.
*/
CAttachment *UserChannel::GetAttachment(void)
{
return m_pUserAttachment;
}
/*
* Void IssueMergeRequest ()
*
* Public
*
* Functional Description:
* This member function is used to cause the Channel object to issue a
* merge request to the pending top provier.
*/
Void UserChannel::IssueMergeRequest ()
{
ChannelAttributes channel_attributes;
CChannelAttributesList merge_channel_list;
CChannelIDList purge_channel_list;
if (m_pConnToTopProvider != NULL)
{
/*
* Fill in the fields of the channel attributes structure so that it
* accurately describes this channel. Then put the structure into the
* merge channel list.
*/
channel_attributes.channel_type = USER_CHANNEL;
if (m_JoinedAttachmentList.IsEmpty() == FALSE)
channel_attributes.u.user_channel_attributes.joined = TRUE;
else
channel_attributes.u.user_channel_attributes.joined = FALSE;
channel_attributes.u.user_channel_attributes.user_id = Channel_ID;
merge_channel_list.Append(&channel_attributes);
/*
* Send the merge request to the indicated provider.
*/
m_pConnToTopProvider->MergeChannelsRequest(&merge_channel_list, &purge_channel_list);
}
}
/*
* Void ChannelJoinRequest ()
*
* Public
*
* Functional Description:
* This function overrides the base class implementation. The main
* difference is that this implementation only allows a user to join
* their own channel. No one else is allowed to join it.
*
* Also, since it is possible to have a user channel object with no one
* joined to it, this request will be forwarded upward to the Top
* Provider from here (unless this is the Top Provider).
*/
Void UserChannel::ChannelJoinRequest (
CAttachment *pOrigAtt,
UserID uidInitiator,
ChannelID channel_id)
{
/*
* See if the requesting user ID is the same as that of the user this
* UserChannel object represents.
*/
if (uidInitiator == Channel_ID)
{
/*
* See if the user is already joined to the channel.
*/
if (m_JoinedAttachmentList.Find(pOrigAtt) == FALSE)
{
/*
* The user is not joined to the channel. If this is the Top
* Provider, then the request can be processed here.
*/
if (IsTopProvider())
{
/*
* Add the user to its own channel, and issue a successful
* channel join confirm to the user.
*/
TRACE_OUT (("UserChannel::ChannelJoinRequest: "
"user joining own user ID channel = %04X",
uidInitiator));
m_JoinedAttachmentList.Append(pOrigAtt);
pOrigAtt->ChannelJoinConfirm(RESULT_SUCCESSFUL, uidInitiator, channel_id, Channel_ID);
}
else
{
/*
* This is not the Top Provider. Forward the join request
* upward to the Top Provider.
*/
TRACE_OUT (("UserChannel::ChannelJoinRequest: "
"forwarding join request to Top Provider"));
m_pConnToTopProvider->ChannelJoinRequest(uidInitiator, Channel_ID);
}
}
else
{
/*
* The user is already joined to their channel. Go ahead and
* issue a successful channel join confirm.
*/
WARNING_OUT (("UserChannel::ChannelJoinRequest: "
"user already joined to own user channel"));
pOrigAtt->ChannelJoinConfirm(RESULT_SUCCESSFUL, uidInitiator, channel_id, Channel_ID);
}
}
else
{
/*
* Someone is trying to join someone elses channel. This is not
* valid. Reject the request without further processing.
*/
WARNING_OUT (("UserChannel::ChannelJoinRequest: "
"rejecting attempt to join someone elses user channel"));
pOrigAtt->ChannelJoinConfirm(RESULT_OTHER_USER_ID, uidInitiator, channel_id, 0);
}
}
/*
* Void SendDataRequest ()
*
* Public
*
* Functional Description:
* This function is used to send data through the channel. Note that data
* is NEVER sent upward, since the user (who is the only one who can be
* joined to this channel) is in the sub-tree of this provider. This helps
* to optimize network traffic.
*/
Void UserChannel::SendDataRequest (
CAttachment *pOrigAtt,
UINT type,
PDataPacket data_packet)
{
CAttachment *pAtt;
ASSERT (Channel_ID == data_packet->GetChannelID());
/*
* Iterate through the attachment list, sending the data to all
* the attachments (except for one from whence the data came).
*/
m_JoinedAttachmentList.Reset();
while (NULL != (pAtt = m_JoinedAttachmentList.Iterate()))
{
if (pAtt != pOrigAtt)
{
pAtt->SendDataIndication(type, data_packet);
}
}
}