private void OnConversation(Ddeml.MONCONVSTRUCT mon)
{
StringBuilder psz;
int length;
// Get the service name from the hszSvc string handle.
psz = new StringBuilder(Ddeml.MAX_STRING_SIZE);
length = Ddeml.DdeQueryString(_Context.InstanceId, mon.hszSvc, psz, psz.Capacity, Ddeml.CP_WINANSI);
string service = psz.ToString();
// Get the topic name from the hszTopic string handle.
psz = new StringBuilder(Ddeml.MAX_STRING_SIZE);
length = Ddeml.DdeQueryString(_Context.InstanceId, mon.hszTopic, psz, psz.Capacity, Ddeml.CP_WINANSI);
string topic = psz.ToString();
DdemlConversationActivityEventArgs args = new DdemlConversationActivityEventArgs(
service,
topic,
mon.fConnect,
mon.hConvClient,
mon.hConvServer,
mon.hTask);
if (ConversationActivity != null)
{
ConversationActivity(this, args);
}
}
private void OnLink(Ddeml.MONLINKSTRUCT mon)
{
// Get the service name from the hszSvc string handle.
var psz = new StringBuilder(Ddeml.MAX_STRING_SIZE);
var length = Ddeml.DdeQueryString(_Context.InstanceId, mon.hszSvc, psz, psz.Capacity,
Ddeml.CP_WINANSI);
var service = psz.ToString();
// Get the topic name from the hszTopic string handle.
psz = new StringBuilder(Ddeml.MAX_STRING_SIZE);
length = Ddeml.DdeQueryString(_Context.InstanceId, mon.hszTopic, psz, psz.Capacity,
Ddeml.CP_WINANSI);
var topic = psz.ToString();
// Get the item name from the hszItem string handle.
psz = new StringBuilder(Ddeml.MAX_STRING_SIZE);
length = Ddeml.DdeQueryString(_Context.InstanceId, mon.hszItem, psz, psz.Capacity,
Ddeml.CP_WINANSI);
var item = psz.ToString();
var args = new DdemlLinkActivityEventArgs(
service,
topic,
item,
mon.wFmt,
!mon.fNoData,
mon.fEstablished,
mon.fServer,
mon.hConvClient,
mon.hConvServer,
mon.hTask);
LinkActivity?.Invoke(this, args);
}
private void OnString(Ddeml.MONHSZSTRUCT mon)
{
// Get the string from the hsz string handle.
// TODO: For some reason this does not work correctly.
var psz = new StringBuilder(Ddeml.MAX_STRING_SIZE);
int length = Ddeml.DdeQueryString(_Context.InstanceId, mon.hsz, psz, psz.Capacity,
Ddeml.CP_WINANSI);
string str = psz.ToString();
var action = DdemlStringActivityType.CleanUp;
switch (mon.fsAction)
{
case Ddeml.MH_CLEANUP:
action = DdemlStringActivityType.CleanUp;
break;
case Ddeml.MH_CREATE:
action = DdemlStringActivityType.Create;
break;
case Ddeml.MH_DELETE:
action = DdemlStringActivityType.Delete;
break;
case Ddeml.MH_KEEP:
action = DdemlStringActivityType.Keep;
break;
}
var args = new DdemlStringActivityEventArgs(str, action, mon.hTask);
if (StringActivity != null)
StringActivity(this, args);
}
private void OnString(Ddeml.MONHSZSTRUCT mon)
{
// Get the string from the hsz string handle.
// TODO: For some reason this does not work correctly.
var psz = new StringBuilder(Ddeml.MAX_STRING_SIZE);
var length = Ddeml.DdeQueryString(_Context.InstanceId, mon.hsz, psz, psz.Capacity,
Ddeml.CP_WINANSI);
var str = psz.ToString();
var action = mon.fsAction switch
{
Ddeml.MH_CLEANUP => DdemlStringActivityType.CleanUp,
Ddeml.MH_CREATE => DdemlStringActivityType.Create,
Ddeml.MH_DELETE => DdemlStringActivityType.Delete,
Ddeml.MH_KEEP => DdemlStringActivityType.Keep,
_ => DdemlStringActivityType.CleanUp
};
var args = new DdemlStringActivityEventArgs(str, action, mon.hTask);
StringActivity?.Invoke(this, args);
}
internal bool ProcessCallback(DdemlTransaction transaction)
{
// This is here to alias the transaction object with a shorter variable name.
DdemlTransaction t = transaction;
switch (t.uType)
{
case Ddeml.XTYP_ADVREQ:
{
StringBuilder psz;
int length;
// Get the topic name from the hsz1 string handle.
psz = new StringBuilder(Ddeml.MAX_STRING_SIZE);
length = Ddeml.DdeQueryString(_InstanceId, t.hsz1, psz, psz.Capacity, Ddeml.CP_WINANSI);
string topic = psz.ToString();
// Get the item name from the hsz2 string handle.
psz = new StringBuilder(Ddeml.MAX_STRING_SIZE);
length = Ddeml.DdeQueryString(_InstanceId, t.hsz2, psz, psz.Capacity, Ddeml.CP_WINANSI);
string item = psz.ToString();
// Create the advise request cache key.
string key = topic + "!" + item + ":" + t.uFmt.ToString();
// Get the data being advised if the cache does not contain it already.
if (!_AdviseRequestCache.ContainsKey(key))
{
// Get the data from the subclass.
byte[] data = OnAdvise(topic, item, t.uFmt);
// Add the data to the cache because it will be needed later.
_AdviseRequestCache.Add(key, data);
}
// Get the data from the advise request cache.
byte[] cached = _AdviseRequestCache[key];
// Get the number of remaining transactions of this type for the same topic name, item name, and format tuple.
int remaining = t.dwData1.ToInt32();
// If this is the last transaction then free the data handle.
if (remaining == 0)
{
// TODO: Does the data handle really need to be freed here?
// Remove the data from the cache because it is no longer needed.
_AdviseRequestCache.Remove(key);
}
// Create and return the data handle representing the data being advised.
if (cached != null && cached.Length > 0)
{
t.dwRet = Ddeml.DdeCreateDataHandle(_InstanceId, cached, cached.Length, 0, t.hsz2, t.uFmt, 0);
return true;
}
// This transaction could not be processed here.
return false;
}
case Ddeml.XTYP_ADVSTART:
{
// Get the item name from the hsz2 string handle.
StringBuilder psz = new StringBuilder(Ddeml.MAX_STRING_SIZE);
int length = Ddeml.DdeQueryString(_InstanceId, t.hsz2, psz, psz.Capacity, Ddeml.CP_WINANSI);
string item = psz.ToString();
// Get the Conversation from the conversation table.
DdemlConversation conversation = _ConversationTable[t.hConv];
// Get a value indicating whether an advise loop should be initiated from the subclass.
t.dwRet = OnStartAdvise(conversation, item, t.uFmt) ? new IntPtr(1) : IntPtr.Zero;
return true;
}
case Ddeml.XTYP_ADVSTOP:
{
// Get the item name from the hsz2 string handle.
StringBuilder psz = new StringBuilder(Ddeml.MAX_STRING_SIZE);
int length = Ddeml.DdeQueryString(_InstanceId, t.hsz2, psz, psz.Capacity, Ddeml.CP_WINANSI);
string item = psz.ToString();
// Get the Conversation from the conversation table.
DdemlConversation conversation = _ConversationTable[t.hConv];
// Inform the subclass that the advise loop has been terminated.
OnStopAdvise(conversation, item);
// Return zero to indicate that there are no problems.
t.dwRet = IntPtr.Zero;
return true;
}
case Ddeml.XTYP_CONNECT:
{
// Get the topic name from the hsz1 string handle.
StringBuilder psz = new StringBuilder(Ddeml.MAX_STRING_SIZE);
int length = Ddeml.DdeQueryString(_InstanceId, t.hsz1, psz, psz.Capacity, Ddeml.CP_WINANSI);
string topic = psz.ToString();
// Get a value from the subclass indicating whether the connection should be allowed.
t.dwRet = OnBeforeConnect(topic) ? new IntPtr(1) : IntPtr.Zero;
return true;
}
case Ddeml.XTYP_CONNECT_CONFIRM:
{
// Get the topic name from the hsz1 string handle.
StringBuilder psz = new StringBuilder(Ddeml.MAX_STRING_SIZE);
int length = Ddeml.DdeQueryString(_InstanceId, t.hsz1, psz, psz.Capacity, Ddeml.CP_WINANSI);
string topic = psz.ToString();
// Create a Conversation object and add it to the conversation table.
_ConversationTable.Add(t.hConv, new DdemlConversation(t.hConv, _Service, topic));
// Inform the subclass that a conversation has been established.
OnAfterConnect(_ConversationTable[t.hConv]);
// Return zero to indicate that there are no problems.
t.dwRet = IntPtr.Zero;
return true;
}
case Ddeml.XTYP_DISCONNECT:
{
// Get the Conversation from the conversation table.
DdemlConversation conversation = _ConversationTable[t.hConv];
// Remove the Conversation from the conversation table.
_ConversationTable.Remove(t.hConv);
// Inform the subclass that the conversation has been disconnected.
OnDisconnect(conversation);
// Return zero to indicate that there are no problems.
t.dwRet = IntPtr.Zero;
return true;
}
case Ddeml.XTYP_EXECUTE:
{
// Get the command from the data handle.
int length = Ddeml.DdeGetData(t.hData, null, 0, 0);
byte[] data = new byte[length];
length = Ddeml.DdeGetData(t.hData, data, data.Length, 0);
string command = _Context.Encoding.GetString(data, 0, data.Length);
if (command[command.Length - 1] == '\0')
{
command = command.Substring(0, command.Length - 1);
}
// Get the Conversation from the conversation table.
DdemlConversation conversation = _ConversationTable[t.hConv];
// Send the command to the subclass and get the result.
ExecuteResult result = OnExecute(conversation, command);
// Return DDE_FACK if the subclass processed the command successfully.
if (result == ExecuteResult.Processed)
{
t.dwRet = new IntPtr(Ddeml.DDE_FACK);
return true;
}
// Return CBR_BLOCK if the subclass needs time to process the command.
if (result == ExecuteResult.PauseConversation)
{
// Increment the conversation's waiting count.
conversation.IncrementWaiting();
t.dwRet = new IntPtr(Ddeml.CBR_BLOCK);
return true;
}
// Return DDE_FBUSY if the subclass is too busy.
if (result == ExecuteResult.TooBusy)
{
t.dwRet = new IntPtr(Ddeml.DDE_FBUSY);
return true;
}
// Return DDE_FNOTPROCESSED if the subclass did not process the command.
t.dwRet = new IntPtr(Ddeml.DDE_FNOTPROCESSED);
return true;
}
case Ddeml.XTYP_POKE:
{
// Get the item name from the hsz2 string handle.
StringBuilder psz = new StringBuilder(Ddeml.MAX_STRING_SIZE);
int length = Ddeml.DdeQueryString(_InstanceId, t.hsz2, psz, psz.Capacity, Ddeml.CP_WINANSI);
string item = psz.ToString();
// Get the data from the data handle.
length = Ddeml.DdeGetData(t.hData, null, 0, 0);
byte[] data = new byte[length];
length = Ddeml.DdeGetData(t.hData, data, data.Length, 0);
// Get the Conversation from the conversation table.
DdemlConversation conversation = _ConversationTable[t.hConv];
// Send the data to the subclass and get the result.
PokeResult result = OnPoke(conversation, item, data, t.uFmt);
// Return DDE_FACK if the subclass processed the data successfully.
if (result == PokeResult.Processed)
{
t.dwRet = new IntPtr(Ddeml.DDE_FACK);
return true;
}
// Return CBR_BLOCK if the subclass needs time to process the data.
if (result == PokeResult.PauseConversation)
{
// Increment the conversation's waiting count.
conversation.IncrementWaiting();
t.dwRet = new IntPtr(Ddeml.CBR_BLOCK);
return true;
}
// Return DDE_FBUSY if the subclass is too busy.
if (result == PokeResult.TooBusy)
{
t.dwRet = new IntPtr(Ddeml.DDE_FBUSY);
return true;
}
// Return DDE_FNOTPROCESSED if the subclass did not process the data.
t.dwRet = new IntPtr(Ddeml.DDE_FNOTPROCESSED);
return true;
}
case Ddeml.XTYP_REQUEST:
{
// Get the item name from the hsz2 string handle.
StringBuilder psz = new StringBuilder(Ddeml.MAX_STRING_SIZE);
int length = Ddeml.DdeQueryString(_InstanceId, t.hsz2, psz, psz.Capacity, Ddeml.CP_WINANSI);
string item = psz.ToString();
// Get the Conversation from the conversation table.
DdemlConversation conversation = _ConversationTable[t.hConv];
// Send the request to the subclass and get the result.
RequestResult result = OnRequest(conversation, item, t.uFmt);
// Return a data handle if the subclass processed the request successfully.
if (result == RequestResult.Processed)
{
// Create and return the data handle for the data being requested.
if (result.Data != null)
{
t.dwRet = Ddeml.DdeCreateDataHandle(_InstanceId, result.Data, result.Data.Length, 0, t.hsz2, t.uFmt, 0);
}
return true;
}
// Return CBR_BLOCK if the subclass needs time to process the request.
if (result == RequestResult.PauseConversation)
{
conversation.IncrementWaiting();
t.dwRet = new IntPtr(Ddeml.CBR_BLOCK);
return true;
}
// Return DDE_FNOTPROCESSED if the subclass did not process the command.
t.dwRet = new IntPtr(Ddeml.DDE_FNOTPROCESSED);
return true;
}
}
// This transaction could not be processed here.
return false;
}
internal bool ProcessCallback(DdemlTransaction transaction)
{
// This is here to alias the transaction object with a shorter variable name.
var t = transaction;
switch (t.uType)
{
case Ddeml.XTYP_ADVREQ:
{
// Get the topic name from the hsz1 string handle.
var psz = new StringBuilder(Ddeml.MAX_STRING_SIZE);
var length = Ddeml.DdeQueryString(_InstanceId, t.hsz1, psz, psz.Capacity,
Ddeml.CP_WINANSI);
var topic = psz.ToString();
// Get the item name from the hsz2 string handle.
psz = new StringBuilder(Ddeml.MAX_STRING_SIZE);
length = Ddeml.DdeQueryString(_InstanceId, t.hsz2, psz, psz.Capacity,
Ddeml.CP_WINANSI);
var item = psz.ToString();
// Create the advise request cache key.
var key = topic + "!" + item + ":" + t.uFmt;
// Get the data being advised if the cache does not contain it already.
if (!_AdviseRequestCache.ContainsKey(key))
{
// Get the data from the subclass.
var data = OnAdvise(topic, item, t.uFmt);
// Add the data to the cache because it will be needed later.
_AdviseRequestCache.Add(key, data);
}
// Get the data from the advise request cache.
var cached = _AdviseRequestCache[key];
// Get the number of remaining transactions of this type for the same topic name, item name, and format tuple.
var remaining = t.dwData1.ToInt32();
// If this is the last transaction then free the data handle.
if (remaining == 0)
_AdviseRequestCache.Remove(key);
// Create and return the data handle representing the data being advised.
if (cached == null || cached.Length <= 0) return false;
t.dwRet = Ddeml.DdeCreateDataHandle(_InstanceId, cached, cached.Length,
0, t.hsz2, t.uFmt, 0);
return true;
// This transaction could not be processed here.
}
case Ddeml.XTYP_ADVSTART:
{
// Get the item name from the hsz2 string handle.
var psz = new StringBuilder(Ddeml.MAX_STRING_SIZE);
var length = Ddeml.DdeQueryString(_InstanceId, t.hsz2, psz, psz.Capacity,
Ddeml.CP_WINANSI);
var item = psz.ToString();
// Get the Conversation from the conversation table.
var conversation = _ConversationTable[t.hConv];
// Get a value indicating whether an advise loop should be initiated from the subclass.
t.dwRet = OnStartAdvise(conversation, item, t.uFmt)
? new IntPtr(1)
: IntPtr.Zero;
return true;
}
case Ddeml.XTYP_ADVSTOP:
{
// Get the item name from the hsz2 string handle.
var psz = new StringBuilder(Ddeml.MAX_STRING_SIZE);
var length = Ddeml.DdeQueryString(_InstanceId, t.hsz2, psz, psz.Capacity,
Ddeml.CP_WINANSI);
var item = psz.ToString();
// Get the Conversation from the conversation table.
var conversation = _ConversationTable[t.hConv];
// Inform the subclass that the advise loop has been terminated.
OnStopAdvise(conversation, item);
// Return zero to indicate that there are no problems.
t.dwRet = IntPtr.Zero;
return true;
}
case Ddeml.XTYP_CONNECT:
{
// Get the topic name from the hsz1 string handle.
var psz = new StringBuilder(Ddeml.MAX_STRING_SIZE);
var length = Ddeml.DdeQueryString(_InstanceId, t.hsz1, psz, psz.Capacity,
Ddeml.CP_WINANSI);
var topic = psz.ToString();
// Get a value from the subclass indicating whether the connection should be allowed.
t.dwRet = OnBeforeConnect(topic) ? new IntPtr(1) : IntPtr.Zero;
return true;
}
case Ddeml.XTYP_CONNECT_CONFIRM:
{
// Get the topic name from the hsz1 string handle.
var psz = new StringBuilder(Ddeml.MAX_STRING_SIZE);
var length = Ddeml.DdeQueryString(_InstanceId, t.hsz1, psz, psz.Capacity,
Ddeml.CP_WINANSI);
var topic = psz.ToString();
// Create a Conversation object and add it to the conversation table.
_ConversationTable.Add(t.hConv,
new DdemlConversation(t.hConv, _Service, topic));
// Inform the subclass that a conversation has been established.
OnAfterConnect(_ConversationTable[t.hConv]);
// Return zero to indicate that there are no problems.
t.dwRet = IntPtr.Zero;
return true;
}
case Ddeml.XTYP_DISCONNECT:
{
// Get the Conversation from the conversation table.
var conversation = _ConversationTable[t.hConv];
// Remove the Conversation from the conversation table.
_ConversationTable.Remove(t.hConv);
// Inform the subclass that the conversation has been disconnected.
OnDisconnect(conversation);
// Return zero to indicate that there are no problems.
t.dwRet = IntPtr.Zero;
return true;
}
case Ddeml.XTYP_EXECUTE:
{
// Get the command from the data handle.
var length = Ddeml.DdeGetData(t.hData, null, 0, 0);
var data = new byte[length];
length = Ddeml.DdeGetData(t.hData, data, data.Length, 0);
var command = _Context.Encoding.GetString(data, 0, data.Length);
if (command[^1] == '\0')
private IntPtr OnDdeCallback(int uType, int uFmt, IntPtr hConv, IntPtr hsz1, IntPtr hsz2, IntPtr hData, IntPtr dwData1, IntPtr dwData2)
{
// Create a new transaction object that will be dispatched to a DdemlClient, DdemlServer, or ITransactionFilter.
DdemlTransaction t = new DdemlTransaction(uType, uFmt, hConv, hsz1, hsz2, hData, dwData1, dwData2);
// Run each transaction filter.
foreach (IDdemlTransactionFilter filter in _Filters)
{
if (filter.PreFilterTransaction(t))
{
return t.dwRet;
}
}
// Dispatch the transaction.
switch (uType)
{
case Ddeml.XTYP_ADVDATA:
{
DdemlClient client = _ClientTable[hConv] as DdemlClient;
if (client != null)
{
if (client.ProcessCallback(t))
{
return t.dwRet;
}
}
break;
}
case Ddeml.XTYP_ADVREQ:
{
DdemlServer server = _ServerTable1[hConv] as DdemlServer;
if (server != null)
{
if (server.ProcessCallback(t))
{
return t.dwRet;
}
}
break;
}
case Ddeml.XTYP_ADVSTART:
{
DdemlServer server = _ServerTable1[hConv] as DdemlServer;
if (server != null)
{
if (server.ProcessCallback(t))
{
return t.dwRet;
}
}
break;
}
case Ddeml.XTYP_ADVSTOP:
{
DdemlServer server = _ServerTable1[hConv] as DdemlServer;
if (server != null)
{
if (server.ProcessCallback(t))
{
return t.dwRet;
}
}
break;
}
case Ddeml.XTYP_CONNECT:
{
// Get the service name from the hsz2 string handle.
StringBuilder psz = new StringBuilder(Ddeml.MAX_STRING_SIZE);
int length = Ddeml.DdeQueryString(_InstanceId, hsz2, psz, psz.Capacity, Ddeml.CP_WINANSI);
string service = psz.ToString();
DdemlServer server = _ServerTable2[service] as DdemlServer;
if (server != null)
{
if (server.ProcessCallback(t))
{
return t.dwRet;
}
}
break;
}
case Ddeml.XTYP_CONNECT_CONFIRM:
{
// Get the service name from the hsz2 string handle.
StringBuilder psz = new StringBuilder(Ddeml.MAX_STRING_SIZE);
int length = Ddeml.DdeQueryString(_InstanceId, hsz2, psz, psz.Capacity, Ddeml.CP_WINANSI);
string service = psz.ToString();
DdemlServer server = _ServerTable2[service] as DdemlServer;
if (server != null)
{
_ServerTable1[hConv] = server;
if (server.ProcessCallback(t))
{
return t.dwRet;
}
}
break;
}
case Ddeml.XTYP_DISCONNECT:
{
DdemlClient client = _ClientTable[hConv] as DdemlClient;
if (client != null)
{
_ClientTable[hConv] = null;
if (client.ProcessCallback(t))
{
return t.dwRet;
}
}
DdemlServer server = _ServerTable1[hConv] as DdemlServer;
if (server != null)
{
_ServerTable1[hConv] = null;
if (server.ProcessCallback(t))
{
return t.dwRet;
}
}
break;
}
case Ddeml.XTYP_EXECUTE:
{
DdemlServer server = _ServerTable1[hConv] as DdemlServer;
if (server != null)
{
if (server.ProcessCallback(t))
{
return t.dwRet;
}
}
break;
}
case Ddeml.XTYP_POKE:
{
DdemlServer server = _ServerTable1[hConv] as DdemlServer;
if (server != null)
{
if (server.ProcessCallback(t))
{
return t.dwRet;
}
}
break;
}
case Ddeml.XTYP_REQUEST:
{
DdemlServer server = _ServerTable1[hConv] as DdemlServer;
if (server != null)
{
if (server.ProcessCallback(t))
{
return t.dwRet;
}
}
break;
}
case Ddeml.XTYP_XACT_COMPLETE:
{
DdemlClient client = _ClientTable[hConv] as DdemlClient;
if (client != null)
{
if (client.ProcessCallback(t))
{
return t.dwRet;
}
}
break;
}
case Ddeml.XTYP_WILDCONNECT:
{
// This library does not support wild connects.
return IntPtr.Zero;
}
case Ddeml.XTYP_MONITOR:
{
// Monitors are handled separately in DdemlMonitor.
return IntPtr.Zero;
}
case Ddeml.XTYP_ERROR:
{
// Get the error code, but do nothing with it at this time.
int error = dwData1.ToInt32();
return IntPtr.Zero;
}
case Ddeml.XTYP_REGISTER:
{
if (Register != null)
{
// Get the service name from the hsz1 string handle.
StringBuilder psz = new StringBuilder(Ddeml.MAX_STRING_SIZE);
int length = Ddeml.DdeQueryString(_InstanceId, hsz1, psz, psz.Capacity, Ddeml.CP_WINANSI);
string service = psz.ToString();
Register(this, new DdemlRegistrationEventArgs(service));
}
return IntPtr.Zero;
}
case Ddeml.XTYP_UNREGISTER:
{
if (Unregister != null)
{
// Get the service name from the hsz1 string handle.
StringBuilder psz = new StringBuilder(Ddeml.MAX_STRING_SIZE);
int length = Ddeml.DdeQueryString(_InstanceId, hsz1, psz, psz.Capacity, Ddeml.CP_WINANSI);
string service = psz.ToString();
Unregister(this, new DdemlRegistrationEventArgs(service));
}
return IntPtr.Zero;
}
}
return IntPtr.Zero;
}