Added atfork support.

[wine/multimedia.git] / misc / ddeml.c

/*
 * DDEML library
 *
 * Copyright 1997 Alexandre Julliard
 * Copyright 1997 Len White
 * Copyright 1999 Keith Matthews
 */

/* Only empty stubs for now */

#include <stdlib.h>
#include <string.h>
#include "winbase.h"
#include "windef.h"
#include "wingdi.h"
#include "winuser.h"
#include "ddeml.h"
#include "winerror.h"
#include "heap.h"
#include "debugtools.h"
#include "tchar.h"
#include "winnt.h"

DEFAULT_DEBUG_CHANNEL(ddeml)

/* Has defined in atom.c file.
 */
#define MAX_ATOM_LEN              255

/* Maximum buffer size ( including the '\0' ).
 */
#define MAX_BUFFER_LEN            (MAX_ATOM_LEN + 1)

/*  typedef struct {
        DWORD           nLength;
        LPVOID          lpSecurityDescriptor;
        BOOL            bInheritHandle;
}       SECURITY_ATTRIBUTES; */

/* This is a simple list to keep track of the strings created
 * by DdeCreateStringHandle.  The list is used to free
 * the strings whenever DdeUninitialize is called.
 * This mechanism is not complete and does not handle multiple instances.
 * Most of the DDE API use a DWORD parameter indicating which instance
 * of a given program is calling them.  The API are supposed to
 * associate the data to the instance that created it.
 */
typedef struct tagHSZNode HSZNode;
struct tagHSZNode
{
    HSZNode* next;
    HSZ hsz;
};


typedef struct tagServiceNode ServiceNode;
struct tagServiceNode
{
    ServiceNode* next;
    HSZ hsz;
    BOOL16              FilterOn;
};
typedef struct DDE_HANDLE_ENTRY {
    BOOL16              Monitor;        /* have these two as full Booleans cos they'll be tested frequently */
    BOOL16              Client_only;    /* bit wasteful of space but it will be faster */
    BOOL16              Unicode;        /* Flag to indicate Win32 API used to initialise */
    BOOL16              Win16;          /* flag to indicate Win16 API used to initialize */
    DWORD               Instance_id;  /* needed to track monitor usage */
    struct DDE_HANDLE_ENTRY    *Next_Entry;
    HSZNode     *Node_list;
    PFNCALLBACK         CallBack;
    DWORD               CBF_Flags;
    DWORD               Monitor_flags;
    UINT              Txn_count;      /* count transactions open to simplify closure */
    DWORD               Last_Error; 
    ServiceNode*                ServiceNames;
} DDE_HANDLE_ENTRY;

static DDE_HANDLE_ENTRY *DDE_Handle_Table_Base = NULL;
static DWORD            DDE_Max_Assigned_Instance = 0;  /* OK for present, may have to worry about wrap-around later */
static const char       *DDEInstanceAccess = "DDEMaxInstance";
static const char       *DDEHandleAccess = "DDEHandleAccess";
static HANDLE           inst_count_mutex = 0;
static HANDLE           handle_mutex = 0;

#define TRUE    1
#define FALSE   0


/******************************************************************************
 *            RemoveHSZNodes    (INTERNAL)
 *
 * Remove a node from the list of HSZ nodes.
 *
 ******************************************************************************
 *
 *      Change History
 *
 *  Vn       Date       Author                  Comment
 *
 *  1.0      Dec 1998  Corel/Macadamian    Initial version
 *  1.1      Mar 1999  Keith Matthews      Added multiple instance handling
 *
 */
static void RemoveHSZNode( HSZ hsz, DDE_HANDLE_ENTRY * reference_inst )
{
    HSZNode* pPrev = NULL;
    HSZNode* pCurrent = NULL;

    /* Set the current node at the start of the list.
     */
    pCurrent = reference_inst->Node_list;
    /* While we have more nodes.
     */
    while( pCurrent != NULL )
    {
        /* If we found the node we were looking for.
         */
        if( pCurrent->hsz == hsz )
        {
            /* Remove the node.
             */
            /* If the first node in the list is to to be removed.
             * Set the global list pointer to the next node.
             */
            if( pCurrent == reference_inst->Node_list )
            {
                reference_inst->Node_list = pCurrent->next;
            }
            /* Just fix the pointers has to skip the current
             * node so we can delete it.
             */
            else
            {
                pPrev->next = pCurrent->next;
            }
            /* Destroy this node.
             */
            free( pCurrent );
            break;
        }
        /* Save the previous node pointer.
         */
        pPrev = pCurrent;
        /* Move on to the next node.
         */
        pCurrent = pCurrent->next;
    }
}

/******************************************************************************
 *            FreeAndRemoveHSZNodes    (INTERNAL)
 *
 * Frees up all the strings still allocated in the list and
 * remove all the nodes from the list of HSZ nodes.
 *
 ******************************************************************************
 *
 *      Change History
 *
 *  Vn       Date       Author                  Comment
 *
 *  1.0      Dec 1998  Corel/Macadamian    Initial version
 *  1.1      Mar 1999  Keith Matthews      Added multiple instance handling
 *
 */
static void FreeAndRemoveHSZNodes( DWORD idInst, DDE_HANDLE_ENTRY * reference_inst )
{
    /* Free any strings created in this instance.
     */
    while( reference_inst->Node_list != NULL )
    {
        DdeFreeStringHandle( idInst, reference_inst->Node_list->hsz );
    }
}

/******************************************************************************
 *            InsertHSZNode    (INTERNAL)
 *
 * Insert a node to the head of the list.
 *
 ******************************************************************************
 *
 *      Change History
 *
 *  Vn       Date       Author                  Comment
 *
 *  1.0      Dec 1998  Corel/Macadamian    Initial version
 *  1.1      Mar 1999  Keith Matthews      Added instance handling
 *  1.2      Jun 1999  Keith Matthews      Added Usage count handling
 *
 */
static void InsertHSZNode( HSZ hsz, DDE_HANDLE_ENTRY * reference_inst )
{
    if( hsz != 0 )
    {
        HSZNode* pNew = NULL;
        /* Create a new node for this HSZ.
         */
        pNew = (HSZNode*) malloc( sizeof( HSZNode ) );
        if( pNew != NULL )
        {
            /* Set the handle value.
             */
            pNew->hsz = hsz;
            /* Attach the node to the head of the list. i.e most recently added is first
             */
            pNew->next = reference_inst->Node_list;

            /* The new node is now at the head of the list
             * so set the global list pointer to it.
             */
            reference_inst->Node_list = pNew;
            TRACE("HSZ node list entry added\n");
        }
    }
}

/*****************************************************************************
 *      Find_Instance_Entry
 *
 *      generic routine to return a pointer to the relevant DDE_HANDLE_ENTRY
 *      for an instance Id, or NULL if the entry does not exist
 *
 *      ASSUMES the mutex protecting the handle entry list is reserved before calling
 *
 ******************************************************************************
 *
 *      Change History
 *
 *  Vn       Date       Author                  Comment
 *
 *  1.0      March 1999  Keith Matthews      1st implementation
             */
 DDE_HANDLE_ENTRY *Find_Instance_Entry (DWORD InstId)
{
        DDE_HANDLE_ENTRY * reference_inst;
        reference_inst =  DDE_Handle_Table_Base;
        while ( reference_inst != NULL )
        {
                if ( reference_inst->Instance_id == InstId )
                {
                        TRACE("Instance entry found\n");
                        return reference_inst;
        }
                reference_inst = reference_inst->Next_Entry;
    }
        TRACE("Instance entry missing\n");
        return NULL;
}

/*****************************************************************************
 *      Find_Service_Name
 *
 *      generic routine to return a pointer to the relevant ServiceNode
 *      for a given service name, or NULL if the entry does not exist
 *
 *      ASSUMES the mutex protecting the handle entry list is reserved before calling
 *
 ******************************************************************************
 *
 *      Change History
 *
 *  Vn       Date       Author                  Comment
 *
 *  1.0      May 1999  Keith Matthews      1st implementation
             */
 ServiceNode *Find_Service_Name (HSZ Service_Name, DDE_HANDLE_ENTRY* this_instance)
{
        ServiceNode * reference_name=  this_instance->ServiceNames;
        while ( reference_name != NULL )
        {
                if ( reference_name->hsz == Service_Name )
                {
                        TRACE("Service Name found\n");
                        return reference_name;
        }
                reference_name = reference_name->next;
    }
        TRACE("Service name missing\n");
        return NULL;
}


/******************************************************************************
 *      Release_reserved_mutex
 *
 *      generic routine to release a reserved mutex
 *
 *
 ******************************************************************************
 *
 *      Change History
 *
 *  Vn       Date       Author                  Comment
 *
 *  1.0      Jan 1999  Keith Matthews        Initial version
 *  1.1      Mar 1999  Keith Matthews        Corrected Heap handling. Corrected re-initialisation handling
 *  1.2      Aug 1999  Jürgen Schmied        Corrected error handling
 *
 */
static DWORD Release_reserved_mutex (HANDLE mutex, LPSTR mutex_name, BOOL release_handle_m, BOOL release_this_i , 
    DDE_HANDLE_ENTRY *this_instance)
{
        if (!ReleaseMutex(mutex))
        {
                ERR("ReleaseMutex failed - %s mutex %li\n",mutex_name,GetLastError());
                HeapFree(GetProcessHeap(), 0, this_instance);
                if ( release_handle_m )
                {
                        ReleaseMutex(handle_mutex);
                }
                return DMLERR_SYS_ERROR;
         }
        if ( release_this_i )
        {
                HeapFree(GetProcessHeap(), 0, this_instance);
        }
        return DMLERR_NO_ERROR;
}

/******************************************************************************
 *      WaitForMutex
 *
 *      generic routine to wait for the mutex
 *
 *
 ******************************************************************************
 *
 *      Change History
 *
 *  Vn       Date       Author                  Comment
 *
 *  1.0      Aug 1999  Juergen Schmied       Initial version
 *
 */
static BOOL WaitForMutex (HANDLE mutex)
{
        DWORD result;

        result = WaitForSingleObject(mutex,1000);

        /* both errors should never occur */
        if (WAIT_TIMEOUT == result)
        {
                ERR("WaitForSingleObject timed out\n");
                return FALSE;
        }

        if (WAIT_FAILED == result)
        {
                ERR("WaitForSingleObject failed - error %li\n", GetLastError());
                return FALSE;
        }
        return TRUE;
}
/******************************************************************************
 *              IncrementInstanceId
 *
 *      generic routine to increment the max instance Id and allocate a new application instance
 *
 ******************************************************************************
 *
 *      Change History
 *
 *  Vn       Date       Author                  Comment
 *
 *  1.0      Jan 1999  Keith Matthews        Initial version
 *
 */
DWORD IncrementInstanceId( DDE_HANDLE_ENTRY *this_instance)
{
        SECURITY_ATTRIBUTES s_attrib;

        /*  Need to set up Mutex in case it is not already present */
        /* increment handle count & get value */
        if ( !inst_count_mutex )
        {
                s_attrib.bInheritHandle = TRUE;
                s_attrib.lpSecurityDescriptor = NULL;
                s_attrib.nLength = sizeof(s_attrib);
                inst_count_mutex = CreateMutexA(&s_attrib,1,DDEInstanceAccess); /* 1st time through */
                inst_count_mutex = ConvertToGlobalHandle(inst_count_mutex); /* fixme when having seperate adresspaces*/
        } else {
                if ( !WaitForMutex(inst_count_mutex) )
                {
                        return DMLERR_SYS_ERROR;
                }
        }
        if ( !inst_count_mutex )
        {
                ERR("CreateMutex failed - inst_count %li\n",GetLastError());
                Release_reserved_mutex (handle_mutex,"handle_mutex",0,1,this_instance);
                return DMLERR_SYS_ERROR;
        }
        DDE_Max_Assigned_Instance++;
        this_instance->Instance_id = DDE_Max_Assigned_Instance;
        TRACE("New instance id %ld allocated\n",DDE_Max_Assigned_Instance);
        if (Release_reserved_mutex(inst_count_mutex,"instance_count",1,0,this_instance)) return DMLERR_SYS_ERROR;
        return DMLERR_NO_ERROR;
}

/******************************************************************************
 *              FindNotifyMonitorCallbacks
 *
 *      Routine to find instances that need to be notified via their callback
 *      of some event they are monitoring
 *
 ******************************************************************************
 *
 *      Change History
 *
 *  Vn       Date       Author                  Comment
 *
 *  1.0    May 1999    Keith Matthews       Initial Version
 *
 */

void FindNotifyMonitorCallbacks(DWORD ThisInstance, DWORD DdeEvent )
{
        DDE_HANDLE_ENTRY *InstanceHandle;
        InstanceHandle = DDE_Handle_Table_Base;
        while ( InstanceHandle != NULL )
        {
                if (  (InstanceHandle->Monitor ) && InstanceHandle->Instance_id == ThisInstance )
                {
                        /*   Found an instance registered as monitor and is not ourselves
                         *      use callback to notify where appropriate
                         */
                }
                InstanceHandle = InstanceHandle->Next_Entry;
        }
}

/******************************************************************************
 *              DdeReserveAtom
 *
 *      Routine to make an extra Add on an atom to reserve it a bit longer
 *
 ******************************************************************************
 *
 *      Change History
 *
 *  Vn       Date       Author                  Comment
 *
 *  1.0    Jun 1999    Keith Matthews       Initial Version
 *
 */

static void DdeReserveAtom( DDE_HANDLE_ENTRY * reference_inst,HSZ hsz)
{
  if ( reference_inst->Unicode)
  {
        WCHAR SNameBuffer[MAX_BUFFER_LEN];
        GlobalGetAtomNameW(hsz,SNameBuffer,MAX_BUFFER_LEN);
        GlobalAddAtomW(SNameBuffer);
  } else {
        CHAR SNameBuffer[MAX_BUFFER_LEN];
        GlobalGetAtomNameA(hsz,SNameBuffer,MAX_BUFFER_LEN);
        GlobalAddAtomA(SNameBuffer);
  }
}


/******************************************************************************
 *              DdeReleaseAtom
 *
 *      Routine to make a delete on an atom to release it a bit sooner
 *
 ******************************************************************************
 *
 *      Change History
 *
 *  Vn       Date       Author                  Comment
 *
 *  1.0    Jun 1999    Keith Matthews       Initial Version
 *
 */

static void DdeReleaseAtom( DDE_HANDLE_ENTRY * reference_inst,HSZ hsz)
{
    GlobalDeleteAtom( hsz );
}

/******************************************************************************
 *            DdeInitialize16   (DDEML.2)
 */
UINT16 WINAPI DdeInitialize16( LPDWORD pidInst, PFNCALLBACK16 pfnCallback,
                               DWORD afCmd, DWORD ulRes)
{
    TRACE("DdeInitialize16 called - calling DdeInitializeA\n");
    return (UINT16)DdeInitializeA(pidInst,(PFNCALLBACK)pfnCallback,
                                    afCmd, ulRes);
}


/******************************************************************************
 *            DdeInitializeA   (USER32.106)
 */
UINT WINAPI DdeInitializeA( LPDWORD pidInst, PFNCALLBACK pfnCallback,
                                DWORD afCmd, DWORD ulRes )
{
    TRACE("DdeInitializeA called - calling DdeInitializeW\n");
    return DdeInitializeW(pidInst,pfnCallback,afCmd,ulRes);
}


/******************************************************************************
 * DdeInitializeW [USER32.107]
 * Registers an application with the DDEML
 *
 * PARAMS
 *    pidInst     [I] Pointer to instance identifier
 *    pfnCallback [I] Pointer to callback function
 *    afCmd       [I] Set of command and filter flags
 *    ulRes       [I] Reserved
 *
 * RETURNS
 *    Success: DMLERR_NO_ERROR
 *    Failure: DMLERR_DLL_USAGE, DMLERR_INVALIDPARAMETER, DMLERR_SYS_ERROR
 *
 ******************************************************************************
 *
 *      Change History
 *
 *  Vn       Date       Author                  Comment
 *
 *  1.0      Pre 1998  Alexandre/Len         Initial Stub
 *  1.1      Jan 1999  Keith Matthews        Initial (near-)complete version
 *  1.2      Mar 1999  Keith Matthews        Corrected Heap handling, CreateMutex failure handling
 *
 */
UINT WINAPI DdeInitializeW( LPDWORD pidInst, PFNCALLBACK pfnCallback,
                                DWORD afCmd, DWORD ulRes )
{

/*  probably not really capable of handling multiple processes, but should handle
 *      multiple instances within one process */

    SECURITY_ATTRIBUTES *s_att= NULL;
    SECURITY_ATTRIBUTES s_attrib;
    DWORD               err_no = 0;
    DDE_HANDLE_ENTRY *this_instance;
    DDE_HANDLE_ENTRY *reference_inst;
    s_att = &s_attrib;

    if( ulRes )
    {
        ERR("Reserved value not zero?  What does this mean?\n");
        FIXME("(%p,%p,0x%lx,%ld): stub\n", pidInst, pfnCallback,
              afCmd,ulRes);
        /* trap this and no more until we know more */
        return DMLERR_NO_ERROR;
    }
    if (!pfnCallback ) 
    {
        /*  this one may be wrong - MS dll seems to accept the condition, 
            leave this until we find out more !! */


        /* can't set up the instance with nothing to act as a callback */
        TRACE("No callback provided\n");
        return DMLERR_INVALIDPARAMETER; /* might be DMLERR_DLL_USAGE */
     }

     /* grab enough heap for one control struct - not really necessary for re-initialise
      * but allows us to use same validation routines */
     this_instance= (DDE_HANDLE_ENTRY*)HeapAlloc( GetProcessHeap(), 0, sizeof(DDE_HANDLE_ENTRY) );
     if ( this_instance == NULL )
     {
        /* catastrophe !! warn user & abort */
        ERR("Instance create failed - out of memory\n");
        return DMLERR_SYS_ERROR;
     }
     this_instance->Next_Entry = NULL;
     this_instance->Monitor=(afCmd|APPCLASS_MONITOR);

     /* messy bit, spec implies that 'Client Only' can be set in 2 different ways, catch 1 here */

     this_instance->Client_only=afCmd&APPCMD_CLIENTONLY;
     this_instance->Instance_id = *pidInst; /* May need to add calling proc Id */
     this_instance->CallBack=*pfnCallback;
     this_instance->Txn_count=0;
     this_instance->Unicode = TRUE;
     this_instance->Win16 = FALSE;
     this_instance->Node_list = NULL; /* node will be added later */
     this_instance->Monitor_flags = afCmd & MF_MASK;
     this_instance->ServiceNames = NULL;

     /* isolate CBF flags in one go, expect this will go the way of all attempts to be clever !! */

     this_instance->CBF_Flags=afCmd^((afCmd&MF_MASK)|((afCmd&APPCMD_MASK)|(afCmd&APPCLASS_MASK)));

     if ( ! this_instance->Client_only )
     {

        /* Check for other way of setting Client-only !! */

        this_instance->Client_only=(this_instance->CBF_Flags&CBF_FAIL_ALLSVRXACTIONS)
                        ==CBF_FAIL_ALLSVRXACTIONS;
     }

     TRACE("instance created - checking validity \n");

    if( *pidInst == 0 ) {
        /*  Initialisation of new Instance Identifier */
        TRACE("new instance, callback %p flags %lX\n",pfnCallback,afCmd);
        if ( DDE_Max_Assigned_Instance == 0 )
        {
                /*  Nothing has been initialised - exit now ! can return TRUE since effect is the same */
        /*  Need to set up Mutex in case it is not already present */
        s_att->bInheritHandle = TRUE;
        s_att->lpSecurityDescriptor = NULL;
        s_att->nLength = sizeof(s_att);
        handle_mutex = CreateMutexA(s_att,1,DDEHandleAccess);
        handle_mutex = ConvertToGlobalHandle(handle_mutex); /* fixme when having seperate adresspaces*/
        if ( !handle_mutex ) {
                ERR("CreateMutex failed - handle list  %li\n",GetLastError());
                HeapFree(GetProcessHeap(), 0, this_instance);
                return DMLERR_SYS_ERROR;
        }
    } else {
        if ( !WaitForMutex(handle_mutex) )
        {
                return DMLERR_SYS_ERROR;
        }
    }

        TRACE("Handle Mutex created/reserved\n");
        if (DDE_Handle_Table_Base == NULL ) 
        {
                /* can't be another instance in this case, assign to the base pointer */
                DDE_Handle_Table_Base= this_instance;

                /* since first must force filter of XTYP_CONNECT and XTYP_WILDCONNECT for
                 *              present 
                 *      -------------------------------      NOTE NOTE NOTE    --------------------------
                 *              
                 *      the manual is not clear if this condition
                 *      applies to the first call to DdeInitialize from an application, or the 
                 *      first call for a given callback !!!
                */

                this_instance->CBF_Flags=this_instance->CBF_Flags|APPCMD_FILTERINITS;
                TRACE("First application instance detected OK\n");
                /*      allocate new instance ID */
                if ((err_no = IncrementInstanceId( this_instance)) ) return err_no;

        } else {
                /* really need to chain the new one in to the latest here, but after checking conditions
                 *      such as trying to start a conversation from an application trying to monitor */
                reference_inst =  DDE_Handle_Table_Base;
                TRACE("Subsequent application instance - starting checks\n");
                while ( reference_inst->Next_Entry != NULL ) 
                {
                        /*
                        *       This set of tests will work if application uses same instance Id
                        *       at application level once allocated - which is what manual implies
                        *       should happen. If someone tries to be 
                        *       clever (lazy ?) it will fail to pick up that later calls are for
                        *       the same application - should we trust them ?
                        */
                        if ( this_instance->Instance_id == reference_inst->Instance_id) 
                        {
                                /* Check 1 - must be same Client-only state */

                                if ( this_instance->Client_only != reference_inst->Client_only)
                                {
                                        if ( Release_reserved_mutex(handle_mutex,"handle_mutex",0,1,this_instance))
                                                return DMLERR_SYS_ERROR;
                                        return DMLERR_DLL_USAGE;
                                }

                                /* Check 2 - cannot use 'Monitor' with any non-monitor modes */

                                if ( this_instance->Monitor != reference_inst->Monitor) 
                                {
                                        if ( Release_reserved_mutex(handle_mutex,"handle_mutex",0,1,this_instance))
                                                return DMLERR_SYS_ERROR;
                                        return DMLERR_INVALIDPARAMETER;
                                }

                                /* Check 3 - must supply different callback address */

                                if ( this_instance->CallBack == reference_inst->CallBack)
                                {
                                        if ( Release_reserved_mutex(handle_mutex,"handle_mutex",0,1,this_instance))
                                                return DMLERR_SYS_ERROR;
                                        return DMLERR_DLL_USAGE;
                                }
                        }
                        reference_inst = reference_inst->Next_Entry;
                }
                /*  All cleared, add to chain */

                TRACE("Application Instance checks finished\n");
                if ((err_no = IncrementInstanceId( this_instance)) ) return err_no;
                if ( Release_reserved_mutex(handle_mutex,"handle_mutex",0,0,this_instance)) return DMLERR_SYS_ERROR;
                reference_inst->Next_Entry = this_instance;
        }
        *pidInst = this_instance->Instance_id;
        TRACE("New application instance processing finished OK\n");
     } else {
        /* Reinitialisation situation   --- FIX  */
        TRACE("reinitialisation of (%p,%p,0x%lx,%ld): stub\n",pidInst,pfnCallback,afCmd,ulRes);

        if ( !WaitForMutex(handle_mutex)  )
        {
                HeapFree(GetProcessHeap(), 0, this_instance);
                return DMLERR_SYS_ERROR;
        }

        if (DDE_Handle_Table_Base == NULL ) 
        {
                if ( Release_reserved_mutex(handle_mutex,"handle_mutex",0,1,this_instance)) return DMLERR_SYS_ERROR;
                return DMLERR_DLL_USAGE;
        }
        HeapFree(GetProcessHeap(), 0, this_instance); /* finished - release heap space used as work store */
        /* can't reinitialise if we have initialised nothing !! */
        reference_inst =  DDE_Handle_Table_Base;
        /* must first check if we have been given a valid instance to re-initialise !!  how do we do that ? */
        /*
        *       MS allows initialisation without specifying a callback, should we allow addition of the
        *       callback by a later call to initialise ? - if so this lot will have to change
        */
        while ( reference_inst->Next_Entry != NULL )
        {
                if ( *pidInst == reference_inst->Instance_id && pfnCallback == reference_inst->CallBack )
                {
                        /* Check 1 - cannot change client-only mode if set via APPCMD_CLIENTONLY */

                        if (  reference_inst->Client_only )
                        {
                           if  ((reference_inst->CBF_Flags & CBF_FAIL_ALLSVRXACTIONS) != CBF_FAIL_ALLSVRXACTIONS) 
                           {
                                /* i.e. Was set to Client-only and through APPCMD_CLIENTONLY */

                                if ( ! ( afCmd & APPCMD_CLIENTONLY))
                                {
                                        if ( Release_reserved_mutex(handle_mutex,"handle_mutex",0,1,this_instance))
                                                return DMLERR_SYS_ERROR;
                                        return DMLERR_DLL_USAGE;
                                }
                           }
                        }
                        /* Check 2 - cannot change monitor modes */

                        if ( this_instance->Monitor != reference_inst->Monitor) 
                        {
                                if ( Release_reserved_mutex(handle_mutex,"handle_mutex",0,1,this_instance))
                                        return DMLERR_SYS_ERROR;
                                return DMLERR_DLL_USAGE;
                        }

                        /* Check 3 - trying to set Client-only via APPCMD when not set so previously */

                        if (( afCmd&APPCMD_CLIENTONLY) && ! reference_inst->Client_only )
                        {
                                if ( Release_reserved_mutex(handle_mutex,"handle_mutex",0,1,this_instance))
                                        return DMLERR_SYS_ERROR;
                                return DMLERR_DLL_USAGE;
                        }
                        break;
                }
                reference_inst = reference_inst->Next_Entry;
        }
        if ( reference_inst->Next_Entry == NULL )
        {
                /* Crazy situation - trying to re-initialize something that has not beeen initialized !! 
                *       
                *       Manual does not say what we do, cannot return DMLERR_NOT_INITIALIZED so what ?
                */
                if ( Release_reserved_mutex(handle_mutex,"handle_mutex",0,1,this_instance))
                        return DMLERR_SYS_ERROR;
                return DMLERR_INVALIDPARAMETER;
        }
        /*              All checked - change relevant flags */

        reference_inst->CBF_Flags = this_instance->CBF_Flags;
        reference_inst->Client_only = this_instance->Client_only;
        reference_inst->Monitor_flags = this_instance->Monitor_flags;
        if ( Release_reserved_mutex(handle_mutex,"handle_mutex",0,1,this_instance))
                return DMLERR_SYS_ERROR;
     }

    return DMLERR_NO_ERROR;
}


/*****************************************************************
 *            DdeUninitialize16   (DDEML.3)
 */
BOOL16 WINAPI DdeUninitialize16( DWORD idInst )
{
    FIXME(" stub calling DdeUninitialize\n");
    return (BOOL16)DdeUninitialize( idInst );
}


/*****************************************************************
 * DdeUninitialize [USER32.119]  Frees DDEML resources
 *
 * PARAMS
 *    idInst [I] Instance identifier
 *
 * RETURNS
 *    Success: TRUE
 *    Failure: FALSE
 */

BOOL WINAPI DdeUninitialize( DWORD idInst )
{
        /*  Stage one - check if we have a handle for this instance
                                                                        */
        SECURITY_ATTRIBUTES *s_att= NULL;
        SECURITY_ATTRIBUTES s_attrib;
        DDE_HANDLE_ENTRY *this_instance;
        DDE_HANDLE_ENTRY *reference_inst;
        s_att = &s_attrib;

        if ( DDE_Max_Assigned_Instance == 0 )
        {
                /*  Nothing has been initialised - exit now ! can return TRUE since effect is the same */
                return TRUE;
        }

        if ( !WaitForMutex(handle_mutex) )
        {
                return DMLERR_SYS_ERROR;
        }
        TRACE("Handle Mutex created/reserved\n");
        /*  First check instance 
        */
        this_instance = Find_Instance_Entry(idInst);
        if ( this_instance == NULL )
        {
                if ( Release_reserved_mutex(handle_mutex,"handle_mutex",FALSE,FALSE,this_instance)) return FALSE;
                /*
                  *     Needs something here to record NOT_INITIALIZED ready for DdeGetLastError
                */
                return FALSE;
        }
        FIXME("(%ld): partial stub\n", idInst);

        /*   FIXME      ++++++++++++++++++++++++++++++++++++++++++
         *      Needs to de-register all service names
         *      
         */
    /* Free the nodes that were not freed by this instance
     * and remove the nodes from the list of HSZ nodes.
     */
        FreeAndRemoveHSZNodes( idInst, this_instance );
    
        /* OK now delete the instance handle itself */

        if ( DDE_Handle_Table_Base == this_instance )
        {
                /* special case - the first/only entry
                */
                DDE_Handle_Table_Base = this_instance->Next_Entry;
        } else
        {
                /* general case
                */
                reference_inst = DDE_Handle_Table_Base;
                while ( reference_inst->Next_Entry != this_instance )
                {
                        reference_inst = this_instance->Next_Entry;
                }
                reference_inst->Next_Entry = this_instance->Next_Entry;
        }
        /* release the mutex and the heap entry
        */
        if ( Release_reserved_mutex(handle_mutex,"handle_mutex",FALSE,TRUE,this_instance)) 
        {
                /* should record something here, but nothing left to hang it from !!
                */
                return FALSE;
        }
    return TRUE;
}


/*****************************************************************
 * DdeConnectList16 [DDEML.4]
 */

HCONVLIST WINAPI DdeConnectList16( DWORD idInst, HSZ hszService, HSZ hszTopic,
                 HCONVLIST hConvList, LPCONVCONTEXT16 pCC )
{
    return DdeConnectList(idInst, hszService, hszTopic, hConvList, 
                            (LPCONVCONTEXT)pCC);
}


/******************************************************************************
 * DdeConnectList [USER32.93]  Establishes conversation with DDE servers
 *
 * PARAMS
 *    idInst     [I] Instance identifier
 *    hszService [I] Handle to service name string
 *    hszTopic   [I] Handle to topic name string
 *    hConvList  [I] Handle to conversation list
 *    pCC        [I] Pointer to structure with context data
 *
 * RETURNS
 *    Success: Handle to new conversation list
 *    Failure: 0
 */
HCONVLIST WINAPI DdeConnectList( DWORD idInst, HSZ hszService, HSZ hszTopic,
                 HCONVLIST hConvList, LPCONVCONTEXT pCC )
{
    FIXME("(%ld,%d,%d,%d,%p): stub\n", idInst, hszService, hszTopic,
          hConvList,pCC);
    return 1;
}


/*****************************************************************
 * DdeQueryNextServer16 [DDEML.5]
 */
HCONV WINAPI DdeQueryNextServer16( HCONVLIST hConvList, HCONV hConvPrev )
{
    return DdeQueryNextServer(hConvList, hConvPrev);
}


/*****************************************************************
 * DdeQueryNextServer [USER32.112]
 */
HCONV WINAPI DdeQueryNextServer( HCONVLIST hConvList, HCONV hConvPrev )
{
    FIXME("(%d,%d): stub\n",hConvList,hConvPrev);
    return 0;
}

/*****************************************************************
 * DdeQueryStringA [USER32.113]
 *
 *****************************************************************
 *
 *      Change History
 *
 *  Vn       Date       Author                  Comment
 *
 *  1.0      Dec 1998  Corel/Macadamian    Initial version
 *  1.1      Mar 1999  Keith Matthews      Added links to instance table and related processing
 *
 */
DWORD WINAPI DdeQueryStringA(DWORD idInst, HSZ hsz, LPSTR psz, DWORD cchMax, INT iCodePage)
{
    DWORD ret = 0;
    CHAR pString[MAX_BUFFER_LEN];
    DDE_HANDLE_ENTRY *reference_inst;

    FIXME(
         "(%ld, 0x%x, %p, %ld, %d): partial stub\n",
         idInst,
         hsz,
         psz, 
         cchMax,
         iCodePage);
  if ( DDE_Max_Assigned_Instance == 0 )
  {
          /*  Nothing has been initialised - exit now ! */
          /*  needs something for DdeGetLAstError even if the manual doesn't say so */
          return FALSE;
  }
  
        if ( !WaitForMutex(handle_mutex) )
        {
                return FALSE;
        }

  TRACE("Handle Mutex created/reserved\n");

  /*  First check instance 
  */
  reference_inst = Find_Instance_Entry(idInst);
  if ( reference_inst == NULL )
  {
        if ( Release_reserved_mutex(handle_mutex,"handle_mutex",FALSE,FALSE,reference_inst)) return FALSE;
        /*
        Needs something here to record NOT_INITIALIZED ready for DdeGetLastError
        */
        return FALSE;
  }

    if( iCodePage == CP_WINANSI )
    {
        /* If psz is null, we have to return only the length
         * of the string.
         */
        if( psz == NULL )
        {
            psz = pString;
            cchMax = MAX_BUFFER_LEN;
}

        ret = GlobalGetAtomNameA( hsz, (LPSTR)psz, cchMax );
  } else {
        Release_reserved_mutex(handle_mutex,"handle_mutex",FALSE,FALSE,reference_inst);
    }
   TRACE("returning pointer\n"); 
    return ret;
}

/*****************************************************************
 * DdeQueryStringW [USER32.114]
 *
 *****************************************************************
 *
 *      Change History
 *
 *  Vn       Date       Author                  Comment
 *
 *  1.0      Dec 1998  Corel/Macadamian    Initial version
 *
 */

DWORD WINAPI DdeQueryStringW(DWORD idInst, HSZ hsz, LPWSTR psz, DWORD cchMax, INT iCodePage)
{
    DWORD ret = 0;
    WCHAR pString[MAX_BUFFER_LEN];
    int factor = 1;

    FIXME(
         "(%ld, 0x%x, %p, %ld, %d): stub\n",
         idInst,
         hsz,
         psz, 
         cchMax,
         iCodePage);

    if( iCodePage == CP_WINUNICODE )
    {
        /* If psz is null, we have to return only the length
         * of the string.
         */
        if( psz == NULL )
        {
            psz = pString;
            cchMax = MAX_BUFFER_LEN;
            /* Note: According to documentation if the psz parameter
             * was NULL this API must return the length of the string in bytes.
             */
            factor = (int) sizeof(WCHAR)/sizeof(BYTE);
        }
        ret = GlobalGetAtomNameW( hsz, (LPWSTR)psz, cchMax ) * factor;
    }
    return ret;
}

/*****************************************************************
*
*               DdeQueryString16 (DDEML.23)
*
******************************************************************
 *
 *      Change History
 *
 *  Vn       Date       Author                  Comment
 *
 *  1.0      March 1999 K Matthews              stub only
 */

DWORD WINAPI DdeQueryString16(DWORD idInst, HSZ hsz, LPSTR lpsz, DWORD cchMax, INT16 codepage)
{
        FIXME("(%ld, 0x%x, %p, %ld, %d): stub \n", 
         idInst,
         hsz,
         lpsz, 
         cchMax,
         codepage);
        return 0;
}


/*****************************************************************
 *            DdeDisconnectList (DDEML.6)
 */
BOOL16 WINAPI DdeDisconnectList16( HCONVLIST hConvList )
{
    return (BOOL16)DdeDisconnectList(hConvList);
}


/******************************************************************************
 * DdeDisconnectList [USER32.98]  Destroys list and terminates conversations
 *
 * RETURNS
 *    Success: TRUE
 *    Failure: FALSE
 */
BOOL WINAPI DdeDisconnectList(
    HCONVLIST hConvList) /* [in] Handle to conversation list */
{
    FIXME("(%d): stub\n", hConvList);
    return TRUE;
}


/*****************************************************************
 *            DdeConnect16   (DDEML.7)
 */
HCONV WINAPI DdeConnect16( DWORD idInst, HSZ hszService, HSZ hszTopic,
                           LPCONVCONTEXT16 pCC )
{
    FIXME("empty stub\n" );
    return 0;
}


/*****************************************************************
 *            DdeConnect   (USER32.92)
 */
HCONV WINAPI DdeConnect( DWORD idInst, HSZ hszService, HSZ hszTopic,
                           LPCONVCONTEXT pCC )
{
    FIXME("(0x%lx,%d,%d,%p): stub\n",idInst,hszService,hszTopic,
          pCC);
    return 0;
}


/*****************************************************************
 *            DdeDisconnect16   (DDEML.8)
 */
BOOL16 WINAPI DdeDisconnect16( HCONV hConv )
{
    return (BOOL16)DdeDisconnect( hConv );
}

/*****************************************************************
 *            DdeSetUserHandle16 (DDEML.10)
 */
BOOL16 WINAPI DdeSetUserHandle16( HCONV hConv, DWORD id, DWORD hUser )
{
    FIXME("(%d,%ld,%ld): stub\n",hConv,id, hUser );
    return 0;
}

/*****************************************************************
 *            DdeCreateDataHandle16 (DDEML.14)
 */
HDDEDATA WINAPI DdeCreateDataHandle16( DWORD idInst, LPBYTE pSrc, DWORD cb, 
                                     DWORD cbOff, HSZ hszItem, UINT16 wFmt, 
                                     UINT16 afCmd )
{
    return DdeCreateDataHandle(idInst,
                                pSrc,
                                cb,
                                cbOff,
                                hszItem,
                                wFmt,
                                afCmd);
}

/*****************************************************************
 *            DdeCreateDataHandle (USER32.94)
 */
HDDEDATA WINAPI DdeCreateDataHandle( DWORD idInst, LPBYTE pSrc, DWORD cb, 
                                       DWORD cbOff, HSZ hszItem, UINT wFmt, 
                                       UINT afCmd )
{
    FIXME(
          "(%ld,%p,%ld,%ld,0x%x,%d,%d): stub\n",
          idInst,
          pSrc,
          cb,
          cbOff,
           hszItem,
          wFmt, 
          afCmd );

    return 0;
}

/*****************************************************************
 *            DdeDisconnect   (USER32.97)
 */
BOOL WINAPI DdeDisconnect( HCONV hConv )
{
    FIXME("empty stub\n" );
    return 0;
}


/*****************************************************************
 *            DdeReconnect   (DDEML.37) (USER32.115)
 */
HCONV WINAPI DdeReconnect( HCONV hConv )
{
    FIXME("empty stub\n" );
    return 0;
}


/*****************************************************************
 *            DdeCreateStringHandle16   (DDEML.21)
 *
 *****************************************************************
 *
 *      Change History
 *
 *  Vn       Date       Author                  Comment
 *
 *  1.0      ?          ?                       basic stub
 *  1.1      June 1999  Keith Matthews          amended onward call to supply default
 *                                              code page if none supplied by caller
 */
HSZ WINAPI DdeCreateStringHandle16( DWORD idInst, LPCSTR str, INT16 codepage )
{
    if  ( codepage )
    {
    return DdeCreateStringHandleA( idInst, str, codepage );
     } else {
        TRACE("Default codepage supplied\n");
         return DdeCreateStringHandleA( idInst, str, CP_WINANSI);
     }
}


/*****************************************************************
 * DdeCreateStringHandleA [USER32.95]
 *
 * RETURNS
 *    Success: String handle
 *    Failure: 0
 *
 *****************************************************************
 *
 *      Change History
 *
 *  Vn       Date       Author                  Comment
 *
 *  1.0      Dec 1998  Corel/Macadamian    Initial version
 *  1.1      Mar 1999  Keith Matthews      Added links to instance table and related processing
 *
 */
HSZ WINAPI DdeCreateStringHandleA( DWORD idInst, LPCSTR psz, INT codepage )
{
  HSZ hsz = 0;
  DDE_HANDLE_ENTRY *reference_inst;
  TRACE("(%ld,%s,%d): partial stub\n",idInst,debugstr_a(psz),codepage);
  

  if ( DDE_Max_Assigned_Instance == 0 )
  {
          /*  Nothing has been initialised - exit now ! can return FALSE since effect is the same */
          return FALSE;
  }
  
        if ( !WaitForMutex(handle_mutex) )
        {
                return DMLERR_SYS_ERROR;
        }

  TRACE("Handle Mutex created/reserved\n");

  /*  First check instance 
  */
  reference_inst = Find_Instance_Entry(idInst);
  if ( reference_inst == NULL )
  {
        if ( Release_reserved_mutex(handle_mutex,"handle_mutex",FALSE,FALSE,reference_inst)) return 0;
        /*
        Needs something here to record NOT_INITIALIZED ready for DdeGetLastError
        */
        return 0;
  }
  
  if (codepage==CP_WINANSI)
  {
      hsz = GlobalAddAtomA (psz);
      /* Save the handle so we know to clean it when
       * uninitialize is called.
       */
      TRACE("added atom %s with HSZ 0x%x, \n",debugstr_a(psz),hsz);
      InsertHSZNode( hsz, reference_inst );
      if ( Release_reserved_mutex(handle_mutex,"handle_mutex",FALSE,FALSE,reference_inst)) 
        {
                reference_inst->Last_Error = DMLERR_SYS_ERROR;
                return 0;
        }
      TRACE("Returning pointer\n");
      return hsz;
  } else {
        Release_reserved_mutex(handle_mutex,"handle_mutex",FALSE,FALSE,reference_inst);
  }
    TRACE("Returning error\n");
    return 0;  
}


/******************************************************************************
 * DdeCreateStringHandleW [USER32.96]  Creates handle to identify string
 *
 * RETURNS
 *    Success: String handle
 *    Failure: 0
 *
 *****************************************************************
 *
 *      Change History
 *
 *  Vn       Date       Author                  Comment
 *
 *  1.0      Dec 1998  Corel/Macadamian    Initial version
 *  1.1      Mar 1999  Keith Matthews      Added links to instance table and related processing
 *
 */
HSZ WINAPI DdeCreateStringHandleW(
    DWORD idInst,   /* [in] Instance identifier */
    LPCWSTR psz,    /* [in] Pointer to string */
    INT codepage) /* [in] Code page identifier */
{
   DDE_HANDLE_ENTRY *reference_inst;
   HSZ hsz = 0;

   TRACE("(%ld,%s,%d): partial stub\n",idInst,debugstr_w(psz),codepage);
  

  if ( DDE_Max_Assigned_Instance == 0 )
  {
          /*  Nothing has been initialised - exit now ! can return FALSE since effect is the same */
          return FALSE;
  }
  
        if ( !WaitForMutex(handle_mutex) )
        {
                return DMLERR_SYS_ERROR;
        }

  TRACE("CreateString - Handle Mutex created/reserved\n");
  
  /*  First check instance 
  */
  reference_inst = Find_Instance_Entry(idInst);
  if ( reference_inst == NULL )
  {
        if ( Release_reserved_mutex(handle_mutex,"handle_mutex",FALSE,FALSE,reference_inst)) return 0;
        /*
        Needs something here to record NOT_INITIALIZED ready for DdeGetLastError
        */
        return 0;
  }

    FIXME("(%ld,%s,%d): partial stub\n",idInst,debugstr_w(psz),codepage);

  if (codepage==CP_WINUNICODE)
  /*
  Should we be checking this against the unicode/ascii nature of the call to DdeInitialize ?
  */
  {
      hsz = GlobalAddAtomW (psz);
      /* Save the handle so we know to clean it when
       * uninitialize is called.
       */
      InsertHSZNode( hsz, reference_inst );
      if ( Release_reserved_mutex(handle_mutex,"handle_mutex",FALSE,FALSE,reference_inst)) 
        {
                reference_inst->Last_Error = DMLERR_SYS_ERROR;
                return 0;
        }
      TRACE("Returning pointer\n");
      return hsz;
   } else {
        Release_reserved_mutex(handle_mutex,"handle_mutex",FALSE,FALSE,reference_inst);
}
    TRACE("Returning error\n");
  return 0;
}


/*****************************************************************
 *            DdeFreeStringHandle16   (DDEML.22)
 */
BOOL16 WINAPI DdeFreeStringHandle16( DWORD idInst, HSZ hsz )
{
        FIXME("idInst %ld hsz 0x%x\n",idInst,hsz);
    return (BOOL)DdeFreeStringHandle( idInst, hsz );
}


/*****************************************************************
 *            DdeFreeStringHandle   (USER32.101)
 * RETURNS: success: nonzero
 *          fail:    zero
 *
 *****************************************************************
 *
 *      Change History
 *
 *  Vn       Date       Author                  Comment
 *
 *  1.0      Dec 1998  Corel/Macadamian    Initial version
 *  1.1      Apr 1999  Keith Matthews      Added links to instance table and related processing
 *
 */
BOOL WINAPI DdeFreeStringHandle( DWORD idInst, HSZ hsz )
{
    DDE_HANDLE_ENTRY *reference_inst;
    TRACE("(%ld,%d): \n",idInst,hsz);
  if ( DDE_Max_Assigned_Instance == 0 )
{
          /*  Nothing has been initialised - exit now ! can return TRUE since effect is the same */
          return TRUE;
  }

        if ( !WaitForMutex(handle_mutex) )
        {
                return DMLERR_SYS_ERROR;
        }

  TRACE("Handle Mutex created/reserved\n");

  /*  First check instance 
  */
  reference_inst = Find_Instance_Entry(idInst);
  if ( (reference_inst == NULL) || (reference_inst->Node_list == NULL))
  {
        if ( Release_reserved_mutex(handle_mutex,"handle_mutex",FALSE,FALSE,reference_inst)) return TRUE;
          /*  Nothing has been initialised - exit now ! can return TRUE since effect is the same */
          return TRUE;

  }

    /* Remove the node associated with this HSZ.
     */
    RemoveHSZNode( hsz , reference_inst);
    /* Free the string associated with this HSZ.
     */
  Release_reserved_mutex(handle_mutex,"handle_mutex",FALSE,FALSE,reference_inst);
    return GlobalDeleteAtom (hsz) ? 0 : hsz;
}


/*****************************************************************
 *            DdeFreeDataHandle16   (DDEML.19)
 */
BOOL16 WINAPI DdeFreeDataHandle16( HDDEDATA hData )
{
    return (BOOL)DdeFreeDataHandle( hData );
}


/*****************************************************************
 *            DdeFreeDataHandle   (USER32.100)
 */
BOOL WINAPI DdeFreeDataHandle( HDDEDATA hData )
{
    FIXME("empty stub\n" );
    return TRUE;
}




/*****************************************************************
 *            DdeKeepStringHandle16   (DDEML.24)
 */
BOOL16 WINAPI DdeKeepStringHandle16( DWORD idInst, HSZ hsz )
{
    return (BOOL)DdeKeepStringHandle( idInst, hsz );
}


/*****************************************************************
 *            DdeKeepStringHandle  (USER32.108)
 *
 * RETURNS: success: nonzero
 *          fail:    zero
 *
 *****************************************************************
 *
 *      Change History
 *
 *  Vn       Date       Author                  Comment
 *
 *  1.0      ?           ?                 Stub only
 *  1.1      Jun 1999  Keith Matthews      First cut implementation
 *
 */
BOOL WINAPI DdeKeepStringHandle( DWORD idInst, HSZ hsz )
{

  DDE_HANDLE_ENTRY *reference_inst;
  TRACE("(%ld,%d): \n",idInst,hsz);
  if ( DDE_Max_Assigned_Instance == 0 )
  {
          /*  Nothing has been initialised - exit now ! can return FALSE since effect is the same */
          return FALSE;
  }


        if ( !WaitForMutex(handle_mutex) )
        {
                return FALSE;
        }

  TRACE("Handle Mutex created/reserved\n");

  /*  First check instance
  */
  reference_inst = Find_Instance_Entry(idInst);
  if ( (reference_inst == NULL) || (reference_inst->Node_list == NULL))
  {
        if ( Release_reserved_mutex(handle_mutex,"handle_mutex",FALSE,FALSE,reference_inst)) return FALSE;
          /*  Nothing has been initialised - exit now ! can return FALSE since effect is the same */
          return FALSE;
    return FALSE;
   }
  DdeReserveAtom(reference_inst,hsz);
  Release_reserved_mutex(handle_mutex,"handle_mutex",FALSE,FALSE,reference_inst);
    return TRUE;
}


/*****************************************************************
 *            DdeClientTransaction16  (DDEML.11)
 */
HDDEDATA WINAPI DdeClientTransaction16( LPVOID pData, DWORD cbData,
                                        HCONV hConv, HSZ hszItem, UINT16 wFmt,
                                        UINT16 wType, DWORD dwTimeout,
                                        LPDWORD pdwResult )
{
    return DdeClientTransaction( (LPBYTE)pData, cbData, hConv, hszItem,
                                   wFmt, wType, dwTimeout, pdwResult );
}


/*****************************************************************
 *            DdeClientTransaction  (USER32.90)
 */
HDDEDATA WINAPI DdeClientTransaction( LPBYTE pData, DWORD cbData,
                                        HCONV hConv, HSZ hszItem, UINT wFmt,
                                        UINT wType, DWORD dwTimeout,
                                        LPDWORD pdwResult )
{
    FIXME("empty stub\n" );
    return 0;
}

/*****************************************************************
 *
 *            DdeAbandonTransaction16 (DDEML.12)
 *
 */
BOOL16 WINAPI DdeAbandonTransaction16( DWORD idInst, HCONV hConv, 
                                     DWORD idTransaction )
{
    FIXME("empty stub\n" );
    return TRUE;
}


/*****************************************************************
 *
 *            DdeAbandonTransaction (USER32.87)
 *
******************************************************************
 *
 *      Change History
 *
 *  Vn       Date       Author                  Comment
 *
 *  1.0      March 1999 K Matthews              stub only
 */
BOOL WINAPI DdeAbandonTransaction( DWORD idInst, HCONV hConv, 
                                     DWORD idTransaction )
{
    FIXME("empty stub\n" );
    return TRUE;
}

/*****************************************************************
 * DdePostAdvise16 [DDEML.13]
 */
BOOL16 WINAPI DdePostAdvise16( DWORD idInst, HSZ hszTopic, HSZ hszItem )
{
    return (BOOL16)DdePostAdvise(idInst, hszTopic, hszItem);
}


/******************************************************************************
 * DdePostAdvise [USER32.110]  Send transaction to DDE callback function.
 *
 * RETURNS
 *    Success: TRUE
 *    Failure: FALSE
 */
BOOL WINAPI DdePostAdvise(
    DWORD idInst, /* [in] Instance identifier */
    HSZ hszTopic, /* [in] Handle to topic name string */
    HSZ hszItem)  /* [in] Handle to item name string */
{
    FIXME("(%ld,%d,%d): stub\n",idInst,hszTopic,hszItem);
    return TRUE;
}


/*****************************************************************
 *            DdeAddData16 (DDEML.15)
 */
HDDEDATA WINAPI DdeAddData16( HDDEDATA hData, LPBYTE pSrc, DWORD cb,
                            DWORD cbOff )
{
    FIXME("empty stub\n" );
    return 0;
}

/*****************************************************************
 *
 *            DdeAddData (USER32.89)
 *
******************************************************************
 *
 *      Change History
 *
 *  Vn       Date       Author                  Comment
 *
 *  1.0      March 1999 K Matthews              stub only
 */
HDDEDATA WINAPI DdeAddData( HDDEDATA hData, LPBYTE pSrc, DWORD cb,
                            DWORD cbOff )
{
    FIXME("empty stub\n" );
    return 0;
}


/*****************************************************************
 *
 *            DdeImpersonateClient (USER32.105)
 *
******************************************************************
 *
 *      Change History
 *
 *  Vn       Date       Author                  Comment
 *
 *  1.0      March 1999 K Matthews              stub only
 */

BOOL WINAPI DdeImpersonateClient( HCONV hConv)
{
    FIXME("empty stub\n" );
    return TRUE;
}


/*****************************************************************
 *
 *            DdeSetQualityOfService (USER32.116)
 *
******************************************************************
 *
 *      Change History
 *
 *  Vn       Date       Author                  Comment
 *
 *  1.0      March 1999 K Matthews              stub only
 */

BOOL WINAPI DdeSetQualityOfService( HWND hwndClient, CONST SECURITY_QUALITY_OF_SERVICE *pqosNew,
                                        PSECURITY_QUALITY_OF_SERVICE pqosPrev)
{
    FIXME("empty stub\n" );
    return TRUE;
}

/*****************************************************************
 *
 *            DdeSetUserHandle (USER32.117)
 *
******************************************************************
 *
 *      Change History
 *
 *  Vn       Date       Author                  Comment
 *
 *  1.0      March 1999 K Matthews              stub only
 */

BOOL WINAPI DdeSetUserHandle( HCONV hConv, DWORD id, DWORD hUser)
{
    FIXME("empty stub\n" );
    return TRUE;
}

/******************************************************************************
 * DdeGetData [USER32.102]  Copies data from DDE object ot local buffer
 *
 * RETURNS
 *    Size of memory object associated with handle
 */
DWORD WINAPI DdeGetData(
    HDDEDATA hData, /* [in] Handle to DDE object */
    LPBYTE pDst,    /* [in] Pointer to destination buffer */
    DWORD cbMax,    /* [in] Amount of data to copy */
    DWORD cbOff)    /* [in] Offset to beginning of data */
{
    FIXME("(%d,%p,%ld,%ld): stub\n",hData,pDst,cbMax,cbOff);
    return cbMax;
}


/*****************************************************************
 * DdeGetData16 [DDEML.16]
 */
DWORD WINAPI DdeGetData16(
    HDDEDATA hData,
    LPBYTE pDst,
    DWORD cbMax, 
    DWORD cbOff)
{
    return DdeGetData(hData, pDst, cbMax, cbOff);
}


/*****************************************************************
 *            DdeAccessData16 (DDEML.17)
 */
LPBYTE WINAPI DdeAccessData16( HDDEDATA hData, LPDWORD pcbDataSize )
{
     return DdeAccessData(hData, pcbDataSize);
}

/*****************************************************************
 *            DdeAccessData (USER32.88)
 */
LPBYTE WINAPI DdeAccessData( HDDEDATA hData, LPDWORD pcbDataSize )
{
     FIXME("(%d,%p): stub\n", hData, pcbDataSize);
     return 0;
}

/*****************************************************************
 *            DdeUnaccessData16 (DDEML.18)
 */
BOOL16 WINAPI DdeUnaccessData16( HDDEDATA hData )
{
     return DdeUnaccessData(hData);
}

/*****************************************************************
 *            DdeUnaccessData (USER32.118)
 */
BOOL WINAPI DdeUnaccessData( HDDEDATA hData )
{
     FIXME("(0x%x): stub\n", hData);

     return 0;
}

/*****************************************************************
 *            DdeEnableCallback16 (DDEML.26)
 */
BOOL16 WINAPI DdeEnableCallback16( DWORD idInst, HCONV hConv, UINT16 wCmd )
{
     return DdeEnableCallback(idInst, hConv, wCmd);
}

/*****************************************************************
 *            DdeEnableCallback (USER32.99)
 */
BOOL WINAPI DdeEnableCallback( DWORD idInst, HCONV hConv, UINT wCmd )
{
     FIXME("(%ld, 0x%x, %d) stub\n", idInst, hConv, wCmd);

     return 0;
}

/*****************************************************************
 *            DdeNameService16  (DDEML.27)
 */
HDDEDATA WINAPI DdeNameService16( DWORD idInst, HSZ hsz1, HSZ hsz2,
                                  UINT16 afCmd )
{
    return DdeNameService( idInst, hsz1, hsz2, afCmd );
}


/******************************************************************************
 * DdeNameService [USER32.109]  {Un}registers service name of DDE server
 *
 * PARAMS
 *    idInst [I] Instance identifier
 *    hsz1   [I] Handle to service name string
 *    hsz2   [I] Reserved
 *    afCmd  [I] Service name flags
 *
 * RETURNS
 *    Success: Non-zero
 *    Failure: 0
 *
 *****************************************************************
 *
 *      Change History
 *
 *  Vn       Date       Author                  Comment
 *
 *  1.0      ?            ?                Stub
 *  1.1      Apr 1999  Keith Matthews      Added trap for non-existent instance (uninitialised instance 0
 *                                              used by some MS programs for unfathomable reasons)
 *  1.2      May 1999  Keith Matthews      Added parameter validation and basic service name handling.
 *                                         Still needs callback parts
 *
 */
HDDEDATA WINAPI DdeNameService( DWORD idInst, HSZ hsz1, HSZ hsz2,
                UINT afCmd )
{
  ServiceNode* this_service, *reference_service ;
  DDE_HANDLE_ENTRY *this_instance;
  DDE_HANDLE_ENTRY *reference_inst;
  this_service = NULL;

  FIXME("(%ld,%d,%d,%d): stub\n",idInst,hsz1,hsz2,afCmd);

  if ( DDE_Max_Assigned_Instance == 0 )
  {
          /*  Nothing has been initialised - exit now ! 
           *    needs something for DdeGetLastError */
          return 0L;
  }

        if ( !WaitForMutex(handle_mutex) )
        {
                return DMLERR_SYS_ERROR;
        }

   TRACE("Handle Mutex created/reserved\n");

   /*  First check instance
   */
   reference_inst = Find_Instance_Entry(idInst);
   this_instance = reference_inst;
   if  (reference_inst == NULL)
   {
        TRACE("Instance not found as initialised\n");
        if ( Release_reserved_mutex(handle_mutex,"handle_mutex",FALSE,FALSE,this_instance)) return TRUE;
          /*  Nothing has been initialised - exit now ! can return TRUE since effect is the same */
          return FALSE;

   }

  if ( hsz2 != 0L )
  {
        /*      Illegal, reserved parameter
         */
        reference_inst->Last_Error = DMLERR_INVALIDPARAMETER;
        Release_reserved_mutex(handle_mutex,"handle_mutex",FALSE,FALSE,this_instance);
        FIXME("Reserved parameter no-zero !!\n");
        return FALSE;
  }
  if ( hsz1 == 0L )
  {
        /*
         *      General unregister situation
         */
        if ( afCmd != DNS_UNREGISTER )
        {
                /*      don't know if we should check this but it makes sense
                 *      why supply REGISTER or filter flags if de-registering all
                 */
                TRACE("General unregister unexpected flags\n");
                reference_inst->Last_Error = DMLERR_DLL_USAGE;
                Release_reserved_mutex(handle_mutex,"handle_mutex",FALSE,FALSE,this_instance);
                return FALSE;
        }
        /*      Loop to find all registered service and de-register them
         */
        if ( reference_inst->ServiceNames == NULL )
        {
                /*  None to unregister !!  
                 */
                TRACE("General de-register - nothing registered\n");
                reference_inst->Last_Error = DMLERR_DLL_USAGE;
                Release_reserved_mutex(handle_mutex,"handle_mutex",FALSE,FALSE,this_instance);
                return FALSE;
        }  else
        {
                this_service = reference_inst->ServiceNames;
                while ( this_service->next != NULL)
                {
                        TRACE("general deregister - iteration\n");
                        reference_service = this_service;
                        this_service = this_service->next;
                        DdeReleaseAtom(reference_inst,reference_service->hsz);
                        HeapFree(GetProcessHeap(), 0, reference_service); /* finished - release heap space used as work store */
                }
                DdeReleaseAtom(reference_inst,this_service->hsz);
                HeapFree(GetProcessHeap(), 0, this_service); /* finished - release heap space used as work store */
                reference_inst->ServiceNames = NULL;
                TRACE("General de-register - finished\n");
        }
        Release_reserved_mutex(handle_mutex,"handle_mutex",FALSE,FALSE,this_instance);
        return TRUE;
  }
  TRACE("Specific name action detected\n");
  if ( afCmd & DNS_REGISTER )
  {
        /* Register new service name
         */

        this_service = Find_Service_Name( hsz1, reference_inst );
        if ( this_service )
                ERR("Trying to register already registered service!\n");
        else
        {
                TRACE("Adding service name\n");

                DdeReserveAtom(reference_inst, hsz1);

                this_service = (ServiceNode*)HeapAlloc( GetProcessHeap(), 0, sizeof(ServiceNode) );
                this_service->hsz = hsz1;
                this_service->FilterOn = TRUE;

                this_service->next = reference_inst->ServiceNames;
                reference_inst->ServiceNames = this_service;
        }
  }
  if ( afCmd & DNS_UNREGISTER )
  {
        /*      De-register service name
         */

        ServiceNode **pServiceNode = &reference_inst->ServiceNames;
        while ( *pServiceNode && (*pServiceNode)->hsz != hsz1 )
                pServiceNode = &(*pServiceNode)->next;

        this_service = *pServiceNode;
        if ( !this_service )
                ERR("Trying to de-register unregistered service!\n");
        else
        {
                *pServiceNode = this_service->next;
                DdeReleaseAtom(reference_inst,this_service->hsz);
                HeapFree(GetProcessHeap(), 0, this_service);
        }
  }
  if ( afCmd & DNS_FILTERON )
  {
        /*      Set filter flags on to hold notifications of connection
         *
         *      test coded this way as this is the default setting
         */
        this_service = Find_Service_Name( hsz1, reference_inst );
        if ( !this_service )
        {
                /*  trying to filter where no service names !!
                 */
                reference_inst->Last_Error = DMLERR_DLL_USAGE;
                Release_reserved_mutex(handle_mutex,"handle_mutex",FALSE,FALSE,this_instance);
                return FALSE;
        } else 
        {
                this_service->FilterOn = TRUE;
        }
  }
  if ( afCmd & DNS_FILTEROFF )
  {
        /*      Set filter flags on to hold notifications of connection
         */
        this_service = Find_Service_Name( hsz1, reference_inst );
        if ( !this_service )
        {
                /*  trying to filter where no service names !!
                 */
                reference_inst->Last_Error = DMLERR_DLL_USAGE;
                Release_reserved_mutex(handle_mutex,"handle_mutex",FALSE,FALSE,this_instance);
                return FALSE;
        } else 
        {
                this_service->FilterOn = FALSE;
        }
  }
  Release_reserved_mutex(handle_mutex,"handle_mutex",FALSE,FALSE,this_instance);
  return TRUE;
}


/*****************************************************************
 *            DdeGetLastError16  (DDEML.20)
 */
UINT16 WINAPI DdeGetLastError16( DWORD idInst )
{
    return (UINT16)DdeGetLastError( idInst );
}


/******************************************************************************
 * DdeGetLastError [USER32.103]  Gets most recent error code
 *
 * PARAMS
 *    idInst [I] Instance identifier
 *
 * RETURNS
 *    Last error code
 *
 *****************************************************************
 *
 *      Change History
 *
 *  Vn       Date       Author                  Comment
 *
 *  1.0      ?            ?                Stub
 *  1.1      Apr 1999  Keith Matthews      Added response for non-existent instance (uninitialised instance 0
 *                                              used by some MS programs for unfathomable reasons)
 *  1.2      May 1999  Keith Matthews      Added interrogation of Last_Error for instance handle where found.
 *
 */
UINT WINAPI DdeGetLastError( DWORD idInst )
{
    DWORD       error_code;
    DDE_HANDLE_ENTRY *reference_inst;

    FIXME("(%ld): stub\n",idInst);

    if ( DDE_Max_Assigned_Instance == 0 )
    {
          /*  Nothing has been initialised - exit now ! */
          return DMLERR_DLL_NOT_INITIALIZED;
    }

        if ( !WaitForMutex(handle_mutex) )
        {
                return DMLERR_SYS_ERROR;
        }

   TRACE("Handle Mutex created/reserved\n");

   /*  First check instance
   */
   reference_inst = Find_Instance_Entry(idInst);
   if  (reference_inst == NULL) 
   {
        if ( Release_reserved_mutex(handle_mutex,"handle_mutex",FALSE,FALSE,reference_inst)) return TRUE;
          /*  Nothing has been initialised - exit now ! can return TRUE since effect is the same */
          return DMLERR_DLL_NOT_INITIALIZED;

   }
    error_code = reference_inst->Last_Error;
    reference_inst->Last_Error = 0;
    Release_reserved_mutex(handle_mutex,"handle_mutex",FALSE,FALSE,reference_inst);
   return error_code;
}


/*****************************************************************
 *            DdeCmpStringHandles16 (DDEML.36)
 */
INT16 WINAPI DdeCmpStringHandles16( HSZ hsz1, HSZ hsz2 )
{
     return DdeCmpStringHandles(hsz1, hsz2);
}

/*****************************************************************
 *            DdeCmpStringHandles (USER32.91)
 *
 * Compares the value of two string handles.  This comparison is
 * not case sensitive.
 *
 * Returns:
 * -1 The value of hsz1 is zero or less than hsz2
 * 0  The values of hsz 1 and 2 are the same or both zero.
 * 1  The value of hsz2 is zero of less than hsz1
 */
INT WINAPI DdeCmpStringHandles( HSZ hsz1, HSZ hsz2 )
{
    CHAR psz1[MAX_BUFFER_LEN];
    CHAR psz2[MAX_BUFFER_LEN];
    int ret = 0;
    int ret1, ret2;

    TRACE("handle 1, handle 2\n" );

    ret1 = GlobalGetAtomNameA( hsz1, psz1, MAX_BUFFER_LEN );
    ret2 = GlobalGetAtomNameA( hsz2, psz2, MAX_BUFFER_LEN );
    /* Make sure we found both strings.
     */
    if( ret1 == 0 && ret2 == 0 )
    {
        /* If both are not found, return both  "zero strings".
         */
        ret = 0;
    }
    else if( ret1 == 0 )
    {
        /* If hsz1 is a not found, return hsz1 is "zero string".
         */
        ret = -1;
    }
    else if( ret2 == 0 )
    {
        /* If hsz2 is a not found, return hsz2 is "zero string".
         */
        ret = 1;
    }
    else
    {
        /* Compare the two strings we got ( case insensitive ).
         */
        ret = strcasecmp( psz1, psz2 );
        /* Since strcmp returns any number smaller than
         * 0 when the first string is found to be less than
         * the second one we must make sure we are returning
         * the proper values.
         */
        if( ret < 0 )
        {
            ret = -1;
        }
        else if( ret > 0 )
        {
            ret = 1;
        }
    }

    return ret;
}

/*****************************************************************
 *            PackDDElParam (USER32.414)
 *
 * RETURNS
 *   success: nonzero
 *   failure: zero
 */
UINT WINAPI PackDDElParam(UINT msg, UINT uiLo, UINT uiHi)
{
    FIXME("stub.\n");
    return 0;
}


/*****************************************************************
 *            UnpackDDElParam (USER32.562)
 *
 * RETURNS
 *   success: nonzero
 *   failure: zero
 */
UINT WINAPI UnpackDDElParam(UINT msg, UINT lParam,
                              UINT *uiLo, UINT *uiHi)
{
    FIXME("stub.\n");
    return 0;
}


/*****************************************************************
 *            FreeDDElParam (USER32.204)
 *
 * RETURNS
 *   success: nonzero
 *   failure: zero
 */
UINT WINAPI FreeDDElParam(UINT msg, UINT lParam)
{
    FIXME("stub.\n");
    return 0;
}

/*****************************************************************
 *            ReuseDDElParam (USER32.446)
 *
 */
UINT WINAPI ReuseDDElParam(UINT lParam, UINT msgIn, UINT msgOut,
                             UINT uiLi, UINT uiHi)
{
    FIXME("stub.\n");
    return 0;
} 

/******************************************************************
 *              DdeQueryConvInfo16 (DDEML.9)
 *
 */
UINT16 WINAPI DdeQueryConvInfo16( HCONV hconv, DWORD idTransaction , LPCONVINFO16 lpConvInfo)
{
        FIXME("stub.\n");
        return 0;
}


/******************************************************************
 *              DdeQueryConvInfo (USER32.111)
 *
 */
UINT WINAPI DdeQueryConvInfo( HCONV hconv, DWORD idTransaction , LPCONVINFO lpConvInfo)
{
        FIXME("stub.\n");
        return 0;
}