Wine Cross Reference
wine/dlls/kernel32/thunk.c

   /*
    * KERNEL32 thunks and other undocumented stuff
    *
    * Copyright 1996, 1997 Alexandre Julliard
    * Copyright 1997, 1998 Marcus Meissner
    * Copyright 1998       Ulrich Weigand
    *
    * This library is free software; you can redistribute it and/or
    * modify it under the terms of the GNU Lesser General Public
   * License as published by the Free Software Foundation; either
   * version 2.1 of the License, or (at your option) any later version.
   *
   * This library is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   * Lesser General Public License for more details.
   *
   * You should have received a copy of the GNU Lesser General Public
   * License along with this library; if not, write to the Free Software
   * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
   */
  
  #include "config.h"
  #include "wine/port.h"
  
  #include <string.h>
  #include <sys/types.h>
  #include <stdarg.h>
  #include <stdio.h>
  #ifdef HAVE_UNISTD_H
  # include <unistd.h>
  #endif
  
  #ifdef __i386__
  
  #include "windef.h"
  #include "winbase.h"
  #include "winerror.h"
  #include "winternl.h"
  #include "wownt32.h"
  #include "wine/winbase16.h"
  
  #include "wine/debug.h"
  #include "wine/library.h"
  #include "kernel_private.h"
  #include "kernel16_private.h"
  
  WINE_DEFAULT_DEBUG_CHANNEL(thunk);
  
  struct ThunkDataCommon
  {
      char                   magic[4];         /* 00 */
      DWORD                  checksum;         /* 04 */
  };
  
  struct ThunkDataLS16
  {
      struct ThunkDataCommon common;           /* 00 */
      SEGPTR                 targetTable;      /* 08 */
      DWORD                  firstTime;        /* 0C */
  };
  
  struct ThunkDataLS32
  {
      struct ThunkDataCommon common;           /* 00 */
      DWORD *                targetTable;      /* 08 */
      char                   lateBinding[4];   /* 0C */
      DWORD                  flags;            /* 10 */
      DWORD                  reserved1;        /* 14 */
      DWORD                  reserved2;        /* 18 */
      DWORD                  offsetQTThunk;    /* 1C */
      DWORD                  offsetFTProlog;   /* 20 */
  };
  
  struct ThunkDataSL16
  {
      struct ThunkDataCommon common;            /* 00 */
      DWORD                  flags1;            /* 08 */
      DWORD                  reserved1;         /* 0C */
      struct ThunkDataSL *   fpData;            /* 10 */
      SEGPTR                 spData;            /* 14 */
      DWORD                  reserved2;         /* 18 */
      char                   lateBinding[4];    /* 1C */
      DWORD                  flags2;            /* 20 */
      DWORD                  reserved3;         /* 20 */
      SEGPTR                 apiDatabase;       /* 28 */
  };
  
  struct ThunkDataSL32
  {
      struct ThunkDataCommon common;            /* 00 */
      DWORD                  reserved1;         /* 08 */
      struct ThunkDataSL *   data;              /* 0C */
      char                   lateBinding[4];    /* 10 */
      DWORD                  flags;             /* 14 */
      DWORD                  reserved2;         /* 18 */
      DWORD                  reserved3;         /* 1C */
      DWORD                  offsetTargetTable; /* 20 */
  };
 
 struct ThunkDataSL
 {
 #if 0
     This structure differs from the Win95 original,
     but this should not matter since it is strictly internal to
     the thunk handling routines in KRNL386 / KERNEL32.
 
     For reference, here is the Win95 layout:
 
     struct ThunkDataCommon common;            /* 00 */
     DWORD                  flags1;            /* 08 */
     SEGPTR                 apiDatabase;       /* 0C */
     WORD                   exePtr;            /* 10 */
     WORD                   segMBA;            /* 12 */
     DWORD                  lenMBATotal;       /* 14 */
     DWORD                  lenMBAUsed;        /* 18 */
     DWORD                  flags2;            /* 1C */
     char                   pszDll16[256];     /* 20 */
     char                   pszDll32[256];     /*120 */
 
     We do it differently since all our thunk handling is done
     by 32-bit code. Therefore we do not need to provide
     easy access to this data, especially the process target
     table database, for 16-bit code.
 #endif
 
     struct ThunkDataCommon common;
     DWORD                  flags1;
     struct SLApiDB *       apiDB;
     struct SLTargetDB *    targetDB;
     DWORD                  flags2;
     char                   pszDll16[256];
     char                   pszDll32[256];
 };
 
 struct SLTargetDB
 {
      struct SLTargetDB *   next;
      DWORD                 process;
      DWORD *               targetTable;
 };
 
 struct SLApiDB
 {
     DWORD                  nrArgBytes;
     DWORD                  errorReturnValue;
 };
 
 SEGPTR CALL32_CBClient_RetAddr = 0;
 SEGPTR CALL32_CBClientEx_RetAddr = 0;
 
 extern void __wine_call_from_16_thunk();
 
 /* Push a DWORD on the 32-bit stack */
 static inline void stack32_push( CONTEXT86 *context, DWORD val )
 {
     context->Esp -= sizeof(DWORD);
     *(DWORD *)context->Esp = val;
 }
 
 /* Pop a DWORD from the 32-bit stack */
 static inline DWORD stack32_pop( CONTEXT86 *context )
 {
     DWORD ret = *(DWORD *)context->Esp;
     context->Esp += sizeof(DWORD);
     return ret;
 }
 
 /***********************************************************************
  *                                                                     *
  *                 Win95 internal thunks                               *
  *                                                                     *
  ***********************************************************************/
 
 /***********************************************************************
  *           LogApiThk    (KERNEL.423)
  */
 void WINAPI LogApiThk( LPSTR func )
 {
     TRACE( "%s\n", debugstr_a(func) );
 }
 
 /***********************************************************************
  *           LogApiThkLSF    (KERNEL32.42)
  *
  * NOTE: needs to preserve all registers!
  */
 void WINAPI __regs_LogApiThkLSF( LPSTR func, CONTEXT86 *context )
 {
     TRACE( "%s\n", debugstr_a(func) );
 }
 DEFINE_REGS_ENTRYPOINT( LogApiThkLSF, 1 )
 
 /***********************************************************************
  *           LogApiThkSL    (KERNEL32.44)
  *
  * NOTE: needs to preserve all registers!
  */
 void WINAPI __regs_LogApiThkSL( LPSTR func, CONTEXT86 *context )
 {
     TRACE( "%s\n", debugstr_a(func) );
 }
 DEFINE_REGS_ENTRYPOINT( LogApiThkSL, 1 )
 
 /***********************************************************************
  *           LogCBThkSL    (KERNEL32.47)
  *
  * NOTE: needs to preserve all registers!
  */
 void WINAPI __regs_LogCBThkSL( LPSTR func, CONTEXT86 *context )
 {
     TRACE( "%s\n", debugstr_a(func) );
 }
 DEFINE_REGS_ENTRYPOINT( LogCBThkSL, 1 )
 
 /***********************************************************************
  * Generates a FT_Prolog call.
  *
  *  0FB6D1                  movzbl edx,cl
  *  8B1495xxxxxxxx          mov edx,[4*edx + targetTable]
  *  68xxxxxxxx              push FT_Prolog
  *  C3                      lret
  */
 static void _write_ftprolog(LPBYTE relayCode ,DWORD *targetTable) {
         LPBYTE  x;
 
         x       = relayCode;
         *x++    = 0x0f;*x++=0xb6;*x++=0xd1; /* movzbl edx,cl */
         *x++    = 0x8B;*x++=0x14;*x++=0x95;*(DWORD**)x= targetTable;
         x+=4;   /* mov edx, [4*edx + targetTable] */
         *x++    = 0x68; *(DWORD*)x = (DWORD)GetProcAddress(kernel32_handle,"FT_Prolog");
         x+=4;   /* push FT_Prolog */
         *x++    = 0xC3;         /* lret */
         /* fill rest with 0xCC / int 3 */
 }
 
 /***********************************************************************
  *      _write_qtthunk                                  (internal)
  * Generates a QT_Thunk style call.
  *
  *  33C9                    xor ecx, ecx
  *  8A4DFC                  mov cl , [ebp-04]
  *  8B148Dxxxxxxxx          mov edx, [4*ecx + targetTable]
  *  B8yyyyyyyy              mov eax, QT_Thunk
  *  FFE0                    jmp eax
  */
 static void _write_qtthunk(
         LPBYTE relayCode,       /* [in] start of QT_Thunk stub */
         DWORD *targetTable      /* [in] start of thunk (for index lookup) */
 ) {
         LPBYTE  x;
 
         x       = relayCode;
         *x++    = 0x33;*x++=0xC9; /* xor ecx,ecx */
         *x++    = 0x8A;*x++=0x4D;*x++=0xFC; /* movb cl,[ebp-04] */
         *x++    = 0x8B;*x++=0x14;*x++=0x8D;*(DWORD**)x= targetTable;
         x+=4;   /* mov edx, [4*ecx + targetTable */
         *x++    = 0xB8; *(DWORD*)x = (DWORD)GetProcAddress(kernel32_handle,"QT_Thunk");
         x+=4;   /* mov eax , QT_Thunk */
         *x++    = 0xFF; *x++ = 0xE0;    /* jmp eax */
         /* should fill the rest of the 32 bytes with 0xCC */
 }
 
 /***********************************************************************
  *           _loadthunk
  */
 static LPVOID _loadthunk(LPCSTR module, LPCSTR func, LPCSTR module32,
                          struct ThunkDataCommon *TD32, DWORD checksum)
 {
     struct ThunkDataCommon *TD16;
     HMODULE16 hmod;
     int ordinal;
 
     if ((hmod = LoadLibrary16(module)) <= 32)
     {
         ERR("(%s, %s, %s): Unable to load '%s', error %d\n",
                    module, func, module32, module, hmod);
         return 0;
     }
 
     if (   !(ordinal = NE_GetOrdinal(hmod, func))
         || !(TD16 = MapSL((SEGPTR)NE_GetEntryPointEx(hmod, ordinal, FALSE))))
     {
         ERR("Unable to find thunk data '%s' in %s, required by %s (conflicting/incorrect DLL versions !?).\n",
                    func, module, module32);
         return 0;
     }
 
     if (TD32 && memcmp(TD16->magic, TD32->magic, 4))
     {
         ERR("(%s, %s, %s): Bad magic %c%c%c%c (should be %c%c%c%c)\n",
                    module, func, module32,
                    TD16->magic[0], TD16->magic[1], TD16->magic[2], TD16->magic[3],
                    TD32->magic[0], TD32->magic[1], TD32->magic[2], TD32->magic[3]);
         return 0;
     }
 
     if (TD32 && TD16->checksum != TD32->checksum)
     {
         ERR("(%s, %s, %s): Wrong checksum %08x (should be %08x)\n",
                    module, func, module32, TD16->checksum, TD32->checksum);
         return 0;
     }
 
     if (!TD32 && checksum && checksum != *(LPDWORD)TD16)
     {
         ERR("(%s, %s, %s): Wrong checksum %08x (should be %08x)\n",
                    module, func, module32, *(LPDWORD)TD16, checksum);
         return 0;
     }
 
     return TD16;
 }
 
 /***********************************************************************
  *           GetThunkStuff    (KERNEL32.53)
  */
 LPVOID WINAPI GetThunkStuff(LPCSTR module, LPCSTR func)
 {
     return _loadthunk(module, func, "<kernel>", NULL, 0L);
 }
 
 /***********************************************************************
  *           GetThunkBuff    (KERNEL32.52)
  * Returns a pointer to ThkBuf in the 16bit library SYSTHUNK.DLL.
  */
 LPVOID WINAPI GetThunkBuff(void)
 {
     return GetThunkStuff("SYSTHUNK.DLL", "ThkBuf");
 }
 
 /***********************************************************************
  *              ThunkConnect32          (KERNEL32.@)
  * Connects a 32bit and a 16bit thunkbuffer.
  */
 UINT WINAPI ThunkConnect32(
         struct ThunkDataCommon *TD,  /* [in/out] thunkbuffer */
         LPSTR thunkfun16,            /* [in] win16 thunkfunction */
         LPSTR module16,              /* [in] name of win16 dll */
         LPSTR module32,              /* [in] name of win32 dll */
         HMODULE hmod32,            /* [in] hmodule of win32 dll */
         DWORD dwReason               /* [in] initialisation argument */
 ) {
     BOOL directionSL;
 
     if (!strncmp(TD->magic, "SL01", 4))
     {
         directionSL = TRUE;
 
         TRACE("SL01 thunk %s (%p) <- %s (%s), Reason: %d\n",
               module32, TD, module16, thunkfun16, dwReason);
     }
     else if (!strncmp(TD->magic, "LS01", 4))
     {
         directionSL = FALSE;
 
         TRACE("LS01 thunk %s (%p) -> %s (%s), Reason: %d\n",
               module32, TD, module16, thunkfun16, dwReason);
     }
     else
     {
         ERR("Invalid magic %c%c%c%c\n",
                    TD->magic[0], TD->magic[1], TD->magic[2], TD->magic[3]);
         return 0;
     }
 
     switch (dwReason)
     {
         case DLL_PROCESS_ATTACH:
         {
             struct ThunkDataCommon *TD16;
             if (!(TD16 = _loadthunk(module16, thunkfun16, module32, TD, 0L)))
                 return 0;
 
             if (directionSL)
             {
                 struct ThunkDataSL32 *SL32 = (struct ThunkDataSL32 *)TD;
                 struct ThunkDataSL16 *SL16 = (struct ThunkDataSL16 *)TD16;
                 struct SLTargetDB *tdb;
 
                 if (SL16->fpData == NULL)
                 {
                     ERR("ThunkConnect16 was not called!\n");
                     return 0;
                 }
 
                 SL32->data = SL16->fpData;
 
                 tdb = HeapAlloc(GetProcessHeap(), 0, sizeof(*tdb));
                 tdb->process = GetCurrentProcessId();
                 tdb->targetTable = (DWORD *)(thunkfun16 + SL32->offsetTargetTable);
 
                 tdb->next = SL32->data->targetDB;   /* FIXME: not thread-safe! */
                 SL32->data->targetDB = tdb;
 
                 TRACE("Process %08x allocated TargetDB entry for ThunkDataSL %p\n",
                       GetCurrentProcessId(), SL32->data);
             }
             else
             {
                 struct ThunkDataLS32 *LS32 = (struct ThunkDataLS32 *)TD;
                 struct ThunkDataLS16 *LS16 = (struct ThunkDataLS16 *)TD16;
 
                 LS32->targetTable = MapSL(LS16->targetTable);
 
                 /* write QT_Thunk and FT_Prolog stubs */
                 _write_qtthunk ((LPBYTE)TD + LS32->offsetQTThunk,  LS32->targetTable);
                 _write_ftprolog((LPBYTE)TD + LS32->offsetFTProlog, LS32->targetTable);
             }
             break;
         }
 
         case DLL_PROCESS_DETACH:
             /* FIXME: cleanup */
             break;
     }
 
     return 1;
 }
 
 /**********************************************************************
  *              QT_Thunk                        (KERNEL32.@)
  *
  * The target address is in EDX.
  * The 16bit arguments start at ESP.
  * The number of 16bit argument bytes is EBP-ESP-0x40 (64 Byte thunksetup).
  * So the stack layout is 16bit argument bytes and then the 64 byte
  * scratch buffer.
  * The scratch buffer is used as work space by Windows' QT_Thunk
  * function.
  * As the programs unfortunately don't always provide a fixed size
  * scratch buffer (danger, stack corruption ahead !!), we simply resort
  * to copying over the whole EBP-ESP range to the 16bit stack
  * (as there's no way to safely figure out the param count
  * due to this misbehaviour of some programs).
  * [ok]
  *
  * See DDJ article 9614c for a very good description of QT_Thunk (also
  * available online !).
  *
  * FIXME: DDJ talks of certain register usage rules; I'm not sure
  * whether we cover this 100%.
  */
 void WINAPI __regs_QT_Thunk( CONTEXT86 *context )
 {
     CONTEXT86 context16;
     DWORD argsize;
 
     context16 = *context;
 
     context16.SegFs = wine_get_fs();
     context16.SegGs = wine_get_gs();
     context16.SegCs = HIWORD(context->Edx);
     context16.Eip   = LOWORD(context->Edx);
     /* point EBP to the STACK16FRAME on the stack
      * for the call_to_16 to set up the register content on calling */
     context16.Ebp   = OFFSETOF(NtCurrentTeb()->WOW32Reserved) + FIELD_OFFSET(STACK16FRAME,bp);
 
     /*
      * used to be (problematic):
      * argsize = context->Ebp - context->Esp - 0x40;
      * due to some programs abusing the API, we better assume the full
      * EBP - ESP range for copying instead: */
     argsize = context->Ebp - context->Esp;
 
     /* ok, too much is insane; let's limit param count a bit again */
     if (argsize > 64)
         argsize = 64; /* 32 WORDs */
 
     WOWCallback16Ex( 0, WCB16_REGS, argsize, (void *)context->Esp, (DWORD *)&context16 );
     context->Eax = context16.Eax;
     context->Edx = context16.Edx;
     context->Ecx = context16.Ecx;
 
     /* make sure to update the Win32 ESP, too, in order to throw away
      * the number of parameters that the Win16 function
      * accepted (that it popped from the corresponding Win16 stack) */
     context->Esp +=   LOWORD(context16.Esp) -
                         ( OFFSETOF(NtCurrentTeb()->WOW32Reserved) - argsize );
 }
 DEFINE_REGS_ENTRYPOINT( QT_Thunk, 0 )
 
 
 /**********************************************************************
  *              FT_Prolog                       (KERNEL32.@)
  *
  * The set of FT_... thunk routines is used instead of QT_Thunk,
  * if structures have to be converted from 32-bit to 16-bit
  * (change of member alignment, conversion of members).
  *
  * The thunk function (as created by the thunk compiler) calls
  * FT_Prolog at the beginning, to set up a stack frame and
  * allocate a 64 byte buffer on the stack.
  * The input parameters (target address and some flags) are
  * saved for later use by FT_Thunk.
  *
  * Input:  EDX  16-bit target address (SEGPTR)
  *         CX   bits  0..7   target number (in target table)
  *              bits  8..9   some flags (unclear???)
  *              bits 10..15  number of DWORD arguments
  *
  * Output: A new stackframe is created, and a 64 byte buffer
  *         allocated on the stack. The layout of the stack
  *         on return is as follows:
  *
  *  (ebp+4)  return address to caller of thunk function
  *  (ebp)    old EBP
  *  (ebp-4)  saved EBX register of caller
  *  (ebp-8)  saved ESI register of caller
  *  (ebp-12) saved EDI register of caller
  *  (ebp-16) saved ECX register, containing flags
  *  (ebp-20) bitmap containing parameters that are to be converted
  *           by FT_Thunk; it is initialized to 0 by FT_Prolog and
  *           filled in by the thunk code before calling FT_Thunk
  *  (ebp-24)
  *    ...    (unclear)
  *  (ebp-44)
  *  (ebp-48) saved EAX register of caller (unclear, never restored???)
  *  (ebp-52) saved EDX register, containing 16-bit thunk target
  *  (ebp-56)
  *    ...    (unclear)
  *  (ebp-64)
  *
  *  ESP is EBP-64 after return.
  *
  */
 void WINAPI __regs_FT_Prolog( CONTEXT86 *context )
 {
     /* Build stack frame */
     stack32_push(context, context->Ebp);
     context->Ebp = context->Esp;
 
     /* Allocate 64-byte Thunk Buffer */
     context->Esp -= 64;
     memset((char *)context->Esp, '\0', 64);
 
     /* Store Flags (ECX) and Target Address (EDX) */
     /* Save other registers to be restored later */
     *(DWORD *)(context->Ebp -  4) = context->Ebx;
     *(DWORD *)(context->Ebp -  8) = context->Esi;
     *(DWORD *)(context->Ebp - 12) = context->Edi;
     *(DWORD *)(context->Ebp - 16) = context->Ecx;
 
     *(DWORD *)(context->Ebp - 48) = context->Eax;
     *(DWORD *)(context->Ebp - 52) = context->Edx;
 }
 DEFINE_REGS_ENTRYPOINT( FT_Prolog, 0 )
 
 /**********************************************************************
  *              FT_Thunk                        (KERNEL32.@)
  *
  * This routine performs the actual call to 16-bit code,
  * similar to QT_Thunk. The differences are:
  *  - The call target is taken from the buffer created by FT_Prolog
  *  - Those arguments requested by the thunk code (by setting the
  *    corresponding bit in the bitmap at EBP-20) are converted
  *    from 32-bit pointers to segmented pointers (those pointers
  *    are guaranteed to point to structures copied to the stack
  *    by the thunk code, so we always use the 16-bit stack selector
  *    for those addresses).
  *
  *    The bit #i of EBP-20 corresponds here to the DWORD starting at
  *    ESP+4 + 2*i.
  *
  * FIXME: It is unclear what happens if there are more than 32 WORDs
  *        of arguments, so that the single DWORD bitmap is no longer
  *        sufficient ...
  */
 void WINAPI __regs_FT_Thunk( CONTEXT86 *context )
 {
     DWORD mapESPrelative = *(DWORD *)(context->Ebp - 20);
     DWORD callTarget     = *(DWORD *)(context->Ebp - 52);
 
     CONTEXT86 context16;
     DWORD i, argsize;
     DWORD newstack[32];
     LPBYTE oldstack;
 
     context16 = *context;
 
     context16.SegFs = wine_get_fs();
     context16.SegGs = wine_get_gs();
     context16.SegCs = HIWORD(callTarget);
     context16.Eip   = LOWORD(callTarget);
     context16.Ebp   = OFFSETOF(NtCurrentTeb()->WOW32Reserved) + FIELD_OFFSET(STACK16FRAME,bp);
 
     argsize  = context->Ebp-context->Esp-0x40;
     if (argsize > sizeof(newstack)) argsize = sizeof(newstack);
     oldstack = (LPBYTE)context->Esp;
 
     memcpy( newstack, oldstack, argsize );
 
     for (i = 0; i < 32; i++)    /* NOTE: What about > 32 arguments? */
         if (mapESPrelative & (1 << i))
         {
             SEGPTR *arg = (SEGPTR *)newstack[i];
             *arg = MAKESEGPTR(SELECTOROF(NtCurrentTeb()->WOW32Reserved),
                               OFFSETOF(NtCurrentTeb()->WOW32Reserved) - argsize
                               + (*(LPBYTE *)arg - oldstack));
         }
 
     WOWCallback16Ex( 0, WCB16_REGS, argsize, newstack, (DWORD *)&context16 );
     context->Eax = context16.Eax;
     context->Edx = context16.Edx;
     context->Ecx = context16.Ecx;
 
     context->Esp +=   LOWORD(context16.Esp) -
                         ( OFFSETOF(NtCurrentTeb()->WOW32Reserved) - argsize );
 
     /* Copy modified buffers back to 32-bit stack */
     memcpy( oldstack, newstack, argsize );
 }
 DEFINE_REGS_ENTRYPOINT( FT_Thunk, 0 )
 
 /***********************************************************************
  *              FT_Exit0 (KERNEL32.@)
  *              FT_Exit4 (KERNEL32.@)
  *              FT_Exit8 (KERNEL32.@)
  *              FT_Exit12 (KERNEL32.@)
  *              FT_Exit16 (KERNEL32.@)
  *              FT_Exit20 (KERNEL32.@)
  *              FT_Exit24 (KERNEL32.@)
  *              FT_Exit28 (KERNEL32.@)
  *              FT_Exit32 (KERNEL32.@)
  *              FT_Exit36 (KERNEL32.@)
  *              FT_Exit40 (KERNEL32.@)
  *              FT_Exit44 (KERNEL32.@)
  *              FT_Exit48 (KERNEL32.@)
  *              FT_Exit52 (KERNEL32.@)
  *              FT_Exit56 (KERNEL32.@)
  *
  * One of the FT_ExitNN functions is called at the end of the thunk code.
  * It removes the stack frame created by FT_Prolog, moves the function
  * return from EBX to EAX (yes, FT_Thunk did use EAX for the return
  * value, but the thunk code has moved it from EAX to EBX in the
  * meantime ... :-), restores the caller's EBX, ESI, and EDI registers,
  * and perform a return to the CALLER of the thunk code (while removing
  * the given number of arguments from the caller's stack).
  */
 #define FT_EXIT_RESTORE_REGS \
     "movl %ebx,%eax\n\t" \
     "movl -4(%ebp),%ebx\n\t" \
     "movl -8(%ebp),%esi\n\t" \
     "movl -12(%ebp),%edi\n\t" \
     "leave\n\t"
 
 #define DEFINE_FT_Exit(n) \
     __ASM_STDCALL_FUNC( FT_Exit ## n, 0, FT_EXIT_RESTORE_REGS "ret $" #n )
 
 DEFINE_FT_Exit(0)
 DEFINE_FT_Exit(4)
 DEFINE_FT_Exit(8)
 DEFINE_FT_Exit(12)
 DEFINE_FT_Exit(16)
 DEFINE_FT_Exit(20)
 DEFINE_FT_Exit(24)
 DEFINE_FT_Exit(28)
 DEFINE_FT_Exit(32)
 DEFINE_FT_Exit(36)
 DEFINE_FT_Exit(40)
 DEFINE_FT_Exit(44)
 DEFINE_FT_Exit(48)
 DEFINE_FT_Exit(52)
 DEFINE_FT_Exit(56)
 
 
 /***********************************************************************
  *              ThunkInitLS     (KERNEL32.43)
  * A thunkbuffer link routine
  * The thunkbuf looks like:
  *
  *      00: DWORD       length          ? don't know exactly
  *      04: SEGPTR      ptr             ? where does it point to?
  * The pointer ptr is written into the first DWORD of 'thunk'.
  * (probably correctly implemented)
  * [ok probably]
  * RETURNS
  *      segmented pointer to thunk?
  */
 DWORD WINAPI ThunkInitLS(
         LPDWORD thunk,  /* [in] win32 thunk */
         LPCSTR thkbuf,  /* [in] thkbuffer name in win16 dll */
         DWORD len,      /* [in] thkbuffer length */
         LPCSTR dll16,   /* [in] name of win16 dll */
         LPCSTR dll32    /* [in] name of win32 dll (FIXME: not used?) */
 ) {
         LPDWORD         addr;
 
         if (!(addr = _loadthunk( dll16, thkbuf, dll32, NULL, len )))
                 return 0;
 
         if (!addr[1])
                 return 0;
         *thunk = addr[1];
 
         return addr[1];
 }
 
 /***********************************************************************
  *              Common32ThkLS   (KERNEL32.45)
  *
  * This is another 32->16 thunk, independent of the QT_Thunk/FT_Thunk
  * style thunks. The basic difference is that the parameter conversion
  * is done completely on the *16-bit* side here. Thus we do not call
  * the 16-bit target directly, but call a common entry point instead.
  * This entry function then calls the target according to the target
  * number passed in the DI register.
  *
  * Input:  EAX    SEGPTR to the common 16-bit entry point
  *         CX     offset in thunk table (target number * 4)
  *         DX     error return value if execution fails (unclear???)
  *         EDX.HI number of DWORD parameters
  *
  * (Note that we need to move the thunk table offset from CX to DI !)
  *
  * The called 16-bit stub expects its stack to look like this:
  *     ...
  *   (esp+40)  32-bit arguments
  *     ...
  *   (esp+8)   32 byte of stack space available as buffer
  *   (esp)     8 byte return address for use with 0x66 lret
  *
  * The called 16-bit stub uses a 0x66 lret to return to 32-bit code,
  * and uses the EAX register to return a DWORD return value.
  * Thus we need to use a special assembly glue routine
  * (CallRegisterLongProc instead of CallRegisterShortProc).
  *
  * Finally, we return to the caller, popping the arguments off
  * the stack.  The number of arguments to be popped is returned
  * in the BL register by the called 16-bit routine.
  *
  */
 void WINAPI __regs_Common32ThkLS( CONTEXT86 *context )
 {
     CONTEXT86 context16;
     DWORD argsize;
 
     context16 = *context;
 
     context16.SegFs = wine_get_fs();
     context16.SegGs = wine_get_gs();
     context16.Edi   = LOWORD(context->Ecx);
     context16.SegCs = HIWORD(context->Eax);
     context16.Eip   = LOWORD(context->Eax);
     context16.Ebp   = OFFSETOF(NtCurrentTeb()->WOW32Reserved) + FIELD_OFFSET(STACK16FRAME,bp);
 
     argsize = HIWORD(context->Edx) * 4;
 
     /* FIXME: hack for stupid USER32 CallbackGlueLS routine */
     if (context->Edx == context->Eip)
         argsize = 6 * 4;
 
     /* Note: the first 32 bytes we copy are just garbage from the 32-bit stack, in order to reserve
      *       the space. It is safe to do that since the register function prefix has reserved
      *       a lot more space than that below context->Esp.
      */
     WOWCallback16Ex( 0, WCB16_REGS, argsize + 32, (LPBYTE)context->Esp - 32, (DWORD *)&context16 );
     context->Eax = context16.Eax;
 
     /* Clean up caller's stack frame */
     context->Esp += LOBYTE(context16.Ebx);
 }
 DEFINE_REGS_ENTRYPOINT( Common32ThkLS, 0 )
 
 /***********************************************************************
  *              OT_32ThkLSF     (KERNEL32.40)
  *
  * YET Another 32->16 thunk. The difference to Common32ThkLS is that
  * argument processing is done on both the 32-bit and the 16-bit side:
  * The 32-bit side prepares arguments, copying them onto the stack.
  *
  * When this routine is called, the first word on the stack is the
  * number of argument bytes prepared by the 32-bit code, and EDX
  * contains the 16-bit target address.
  *
  * The called 16-bit routine is another relaycode, doing further
  * argument processing and then calling the real 16-bit target
  * whose address is stored at [bp-04].
  *
  * The call proceeds using a normal CallRegisterShortProc.
  * After return from the 16-bit relaycode, the arguments need
  * to be copied *back* to the 32-bit stack, since the 32-bit
  * relaycode processes output parameters.
  *
  * Note that we copy twice the number of arguments, since some of the
  * 16-bit relaycodes in SYSTHUNK.DLL directly access the original
  * arguments of the caller!
  *
  * (Note that this function seems only to be used for
  *  OLECLI32 -> OLECLI and OLESVR32 -> OLESVR thunking.)
  */
 void WINAPI __regs_OT_32ThkLSF( CONTEXT86 *context )
 {
     CONTEXT86 context16;
     DWORD argsize;
 
     context16 = *context;
 
     context16.SegFs = wine_get_fs();
     context16.SegGs = wine_get_gs();
     context16.SegCs = HIWORD(context->Edx);
     context16.Eip   = LOWORD(context->Edx);
     context16.Ebp   = OFFSETOF(NtCurrentTeb()->WOW32Reserved) + FIELD_OFFSET(STACK16FRAME,bp);
 
     argsize = 2 * *(WORD *)context->Esp + 2;
 
     WOWCallback16Ex( 0, WCB16_REGS, argsize, (void *)context->Esp, (DWORD *)&context16 );
     context->Eax = context16.Eax;
     context->Edx = context16.Edx;
 
     /* Copy modified buffers back to 32-bit stack */
     memcpy( (LPBYTE)context->Esp,
             (LPBYTE)CURRENT_STACK16 - argsize, argsize );
 
     context->Esp +=   LOWORD(context16.Esp) -
                         ( OFFSETOF(NtCurrentTeb()->WOW32Reserved) - argsize );
 }
 DEFINE_REGS_ENTRYPOINT( OT_32ThkLSF, 0 )
 
 /***********************************************************************
  *              ThunkInitLSF            (KERNEL32.41)
  * A thunk setup routine.
  * Expects a pointer to a preinitialized thunkbuffer in the first argument
  * looking like:
  *|     00..03:         unknown (pointer, check _41, _43, _46)
  *|     04: EB1E                jmp +0x20
  *|
  *|     06..23:         unknown (space for replacement code, check .90)
  *|
  *|     24:>E800000000          call offset 29
  *|     29:>58                  pop eax            ( target of call )
  *|     2A: 2D25000000          sub eax,0x00000025 ( now points to offset 4 )
  *|     2F: BAxxxxxxxx          mov edx,xxxxxxxx
  *|     34: 68yyyyyyyy          push KERNEL32.90
  *|     39: C3                  ret
  *|
  *|     3A: EB1E                jmp +0x20
  *|     3E ... 59:      unknown (space for replacement code?)
  *|     5A: E8xxxxxxxx          call <32bitoffset xxxxxxxx>
  *|     5F: 5A                  pop edx
  *|     60: 81EA25xxxxxx        sub edx, 0x25xxxxxx
  *|     66: 52                  push edx
  *|     67: 68xxxxxxxx          push xxxxxxxx
  *|     6C: 68yyyyyyyy          push KERNEL32.89
  *|     71: C3                  ret
  *|     72: end?
  * This function checks if the code is there, and replaces the yyyyyyyy entries
  * by the functionpointers.
  * The thunkbuf looks like:
  *
  *|     00: DWORD       length          ? don't know exactly
  *|     04: SEGPTR      ptr             ? where does it point to?
  * The segpointer ptr is written into the first DWORD of 'thunk'.
  * [ok probably]
  * RETURNS
  *      unclear, pointer to win16 thkbuffer?
  */
 LPVOID WINAPI ThunkInitLSF(
         LPBYTE thunk,   /* [in] win32 thunk */
         LPCSTR thkbuf,  /* [in] thkbuffer name in win16 dll */
         DWORD len,      /* [in] length of thkbuffer */
         LPCSTR dll16,   /* [in] name of win16 dll */
         LPCSTR dll32    /* [in] name of win32 dll */
 ) {
         LPDWORD         addr,addr2;
 
         /* FIXME: add checks for valid code ... */
         /* write pointers to kernel32.89 and kernel32.90 (+ordinal base of 1) */
         *(DWORD*)(thunk+0x35) = (DWORD)GetProcAddress(kernel32_handle,(LPSTR)90);
         *(DWORD*)(thunk+0x6D) = (DWORD)GetProcAddress(kernel32_handle,(LPSTR)89);
 
 
         if (!(addr = _loadthunk( dll16, thkbuf, dll32, NULL, len )))
                 return 0;
 
         addr2 = MapSL(addr[1]);
         if (HIWORD(addr2))
                 *(DWORD*)thunk = (DWORD)addr2;
 
         return addr2;
 }
 
 /***********************************************************************
  *              FT_PrologPrime                  (KERNEL32.89)
  *
  * This function is called from the relay code installed by
  * ThunkInitLSF. It replaces the location from where it was
  * called by a standard FT_Prolog call stub (which is 'primed'
  * by inserting the correct target table pointer).
  * Finally, it calls that stub.
  *
  * Input:  ECX    target number + flags (passed through to FT_Prolog)
  *        (ESP)   offset of location where target table pointer
  *                is stored, relative to the start of the relay code
  *        (ESP+4) pointer to start of relay code
  *                (this is where the FT_Prolog call stub gets written to)
  *
  * Note: The two DWORD arguments get popped off the stack.
  *
  */
 void WINAPI __regs_FT_PrologPrime( CONTEXT86 *context )
 {
     DWORD  targetTableOffset;
     LPBYTE relayCode;
 
     /* Compensate for the fact that the Wine register relay code thought
        we were being called, although we were in fact jumped to */
     context->Esp -= 4;
 
     /* Write FT_Prolog call stub */
     targetTableOffset = stack32_pop(context);
     relayCode = (LPBYTE)stack32_pop(context);
     _write_ftprolog( relayCode, *(DWORD **)(relayCode+targetTableOffset) );
 
     /* Jump to the call stub just created */
     context->Eip = (DWORD)relayCode;
 }
 DEFINE_REGS_ENTRYPOINT( FT_PrologPrime, 0 )
 
 /***********************************************************************
  *              QT_ThunkPrime                   (KERNEL32.90)
  *
  * This function corresponds to FT_PrologPrime, but installs a
  * call stub for QT_Thunk instead.
  *
  * Input: (EBP-4) target number (passed through to QT_Thunk)
  *         EDX    target table pointer location offset
  *         EAX    start of relay code
  *
  */
 void WINAPI __regs_QT_ThunkPrime( CONTEXT86 *context )
 {
     DWORD  targetTableOffset;
     LPBYTE relayCode;
 
     /* Compensate for the fact that the Wine register relay code thought
        we were being called, although we were in fact jumped to */
     context->Esp -= 4;
 
     /* Write QT_Thunk call stub */
     targetTableOffset = context->Edx;
     relayCode = (LPBYTE)context->Eax;
     _write_qtthunk( relayCode, *(DWORD **)(relayCode+targetTableOffset) );
 
     /* Jump to the call stub just created */
     context->Eip = (DWORD)relayCode;
 }
 DEFINE_REGS_ENTRYPOINT( QT_ThunkPrime, 0 )
 
 /***********************************************************************
  *              ThunkInitSL (KERNEL32.46)
  * Another thunkbuf link routine.
  * The start of the thunkbuf looks like this:
  *      00: DWORD       length
  *      04: SEGPTR      address for thunkbuffer pointer
  * [ok probably]
  *
  * RETURNS
  *  Nothing.
  */
 VOID WINAPI ThunkInitSL(
         LPBYTE thunk,           /* [in] start of thunkbuffer */
         LPCSTR thkbuf,          /* [in] name/ordinal of thunkbuffer in win16 dll */
         DWORD len,              /* [in] length of thunkbuffer */
         LPCSTR dll16,           /* [in] name of win16 dll containing the thkbuf */
         LPCSTR dll32            /* [in] win32 dll. FIXME: strange, unused */
 ) {
         LPDWORD         addr;
 
         if (!(addr = _loadthunk( dll16, thkbuf, dll32, NULL, len )))
                 return;
 
         *(DWORD*)MapSL(addr[1]) = (DWORD)thunk;
 }
 
 /**********************************************************************
  *           SSInit             (KERNEL.700)
  * RETURNS
  *      TRUE for success.
  */
 BOOL WINAPI SSInit16(void)
 {
     return TRUE;
 }
 
 /**********************************************************************
  *           SSOnBigStack       (KERNEL32.87)
  * Check if thunking is initialized (ss selector set up etc.)
  * We do that differently, so just return TRUE.
  * [ok]
  * RETURNS
  *      TRUE for success.
  */
 BOOL WINAPI SSOnBigStack(void)
 {
     TRACE("Yes, thunking is initialized\n");
     return TRUE;
 }
 
 /**********************************************************************
  *           SSConfirmSmallStack     (KERNEL.704)
  *
  * Abort if not on small stack.
  *
  * This must be a register routine as it has to preserve *all* registers.
  */
 void WINAPI SSConfirmSmallStack( CONTEXT86 *context )
 {
     /* We are always on the small stack while in 16-bit code ... */
 }
 
 /**********************************************************************
  *           SSCall (KERNEL32.88)
  * One of the real thunking functions. This one seems to be for 32<->32
  * thunks. It should probably be capable of crossing processboundaries.
  *
  * And YES, I've seen nr=48 (somewhere in the Win95 32<->16 OLE coupling)
  * [ok]
  *
  * RETURNS
  *  Thunked function result.
  */
 DWORD WINAPIV SSCall(
         DWORD nr,       /* [in] number of argument bytes */
         DWORD flags,    /* [in] FIXME: flags ? */
         FARPROC fun,    /* [in] function to call */
         ...             /* [in/out] arguments */
 ) {
     DWORD i,ret;
     DWORD *args = ((DWORD *)&fun) + 1;
 
     if(TRACE_ON(thunk))
     {
       DPRINTF("(%d,0x%08x,%p,[",nr,flags,fun);
       for (i=0;i<nr/4;i++)
           DPRINTF("0x%08x,",args[i]);
       DPRINTF("])\n");
     }
     switch (nr) {
     case 0:     ret = fun();
                 break;
     case 4:     ret = fun(args[0]);
                 break;
     case 8:     ret = fun(args[0],args[1]);
                 break;
     case 12:    ret = fun(args[0],args[1],args[2]);
                 break;
     case 16:    ret = fun(args[0],args[1],args[2],args[3]);
                 break;
     case 20:    ret = fun(args[0],args[1],args[2],args[3],args[4]);
                 break;
     case 24:    ret = fun(args[0],args[1],args[2],args[3],args[4],args[5]);
                 break;
     case 28:    ret = fun(args[0],args[1],args[2],args[3],args[4],args[5],args[6]);
                 break;
     case 32:    ret = fun(args[0],args[1],args[2],args[3],args[4],args[5],args[6],args[7]);
                 break;
     case 36:    ret = fun(args[0],args[1],args[2],args[3],args[4],args[5],args[6],args[7],args[8]);
                 break;
     case 40:    ret = fun(args[0],args[1],args[2],args[3],args[4],args[5],args[6],args[7],args[8],args[9]);
                 break;
     case 44:    ret = fun(args[0],args[1],args[2],args[3],args[4],args[5],args[6],args[7],args[8],args[9],args[10]);
                 break;
     case 48:    ret = fun(args[0],args[1],args[2],args[3],args[4],args[5],args[6],args[7],args[8],args[9],args[10],args[11]);
                 break;
     default:
         WARN("Unsupported nr of arguments, %d\n",nr);
         ret = 0;
         break;
 
     }
     TRACE(" returning %d ...\n",ret);
     return ret;
 }
 
 /**********************************************************************
  *           W32S_BackTo32                      (KERNEL32.51)
  */
 void WINAPI __regs_W32S_BackTo32( CONTEXT86 *context )
 {
     LPDWORD stack = (LPDWORD)context->Esp;
     FARPROC proc = (FARPROC)context->Eip;
 
     context->Eax = proc( stack[1], stack[2], stack[3], stack[4], stack[5],
                                stack[6], stack[7], stack[8], stack[9], stack[10] );
 
     context->Eip = stack32_pop(context);
 }
 DEFINE_REGS_ENTRYPOINT( W32S_BackTo32, 0 )
 
 /**********************************************************************
  *                      AllocSLCallback         (KERNEL32.@)
  *
  * Allocate a 16->32 callback.
  *
  * NOTES
  * Win95 uses some structchains for callbacks. It allocates them
  * in blocks of 100 entries, size 32 bytes each, layout:
  * blockstart:
  *|     0:      PTR     nextblockstart
  *|     4:      entry   *first;
  *|     8:      WORD    sel ( start points to blockstart)
  *|     A:      WORD    unknown
  * 100xentry:
  *|     00..17:         Code
  *|     18:     PDB     *owning_process;
  *|     1C:     PTR     blockstart
  *
  * We ignore this for now. (Just a note for further developers)
  * FIXME: use this method, so we don't waste selectors...
  *
  * Following code is then generated by AllocSLCallback. The code is 16 bit, so
  * the 0x66 prefix switches from word->long registers.
  *
  *|     665A            pop     edx
  *|     6668x arg2 x    pushl   <arg2>
  *|     6652            push    edx
  *|     EAx arg1 x      jmpf    <arg1>
  *
  * returns the startaddress of this thunk.
  *
  * Note, that they look very similar to the ones allocates by THUNK_Alloc.
  * RETURNS
  *      A segmented pointer to the start of the thunk
  */
 DWORD WINAPI
 AllocSLCallback(
         DWORD finalizer,        /* [in] Finalizer function */
         DWORD callback          /* [in] Callback function */
 ) {
         LPBYTE  x,thunk = HeapAlloc( GetProcessHeap(), 0, 32 );
         WORD    sel;
 
         x=thunk;
         *x++=0x66;*x++=0x5a;                            /* popl edx */
         *x++=0x66;*x++=0x68;*(DWORD*)x=finalizer;x+=4;  /* pushl finalizer */
         *x++=0x66;*x++=0x52;                            /* pushl edx */
         *x++=0xea;*(DWORD*)x=callback;x+=4;             /* jmpf callback */
 
         *(DWORD*)(thunk+18) = GetCurrentProcessId();
 
         sel = SELECTOR_AllocBlock( thunk, 32, WINE_LDT_FLAGS_CODE );
         return (sel<<16)|0;
 }
 
 /**********************************************************************
  *              FreeSLCallback          (KERNEL32.@)
  * Frees the specified 16->32 callback
  *
  * RETURNS
  *  Nothing.
  */
 void WINAPI
 FreeSLCallback(
         DWORD x /* [in] 16 bit callback (segmented pointer?) */
 ) {
         FIXME("(0x%08x): stub\n",x);
 }
 
 /**********************************************************************
  *              AllocMappedBuffer       (KERNEL32.38)
  *
  * This is an undocumented KERNEL32 function that
  * SMapLS's a GlobalAlloc'ed buffer.
  *
  * RETURNS
  *       EDI register: pointer to buffer
  *
  * NOTES
  *       The buffer is preceded by 8 bytes:
  *        ...
  *       edi+0   buffer
  *       edi-4   SEGPTR to buffer
  *       edi-8   some magic Win95 needs for SUnMapLS
  *               (we use it for the memory handle)
  *
  *       The SEGPTR is used by the caller!
  */
 void WINAPI __regs_AllocMappedBuffer(
               CONTEXT86 *context /* [in] EDI register: size of buffer to allocate */
 ) {
     HGLOBAL handle = GlobalAlloc(0, context->Edi + 8);
     DWORD *buffer = GlobalLock(handle);
     DWORD ptr = 0;
 
     if (buffer)
         if (!(ptr = MapLS(buffer + 2)))
         {
             GlobalUnlock(handle);
             GlobalFree(handle);
         }
 
     if (!ptr)
         context->Eax = context->Edi = 0;
     else
     {
         buffer[0] = (DWORD)handle;
         buffer[1] = ptr;
 
         context->Eax = ptr;
         context->Edi = (DWORD)(buffer + 2);
     }
 }
 DEFINE_REGS_ENTRYPOINT( AllocMappedBuffer, 0 )
 
 /**********************************************************************
  *              FreeMappedBuffer        (KERNEL32.39)
  *
  * Free a buffer allocated by AllocMappedBuffer
  *
  * RETURNS
  *  Nothing.
  */
 void WINAPI __regs_FreeMappedBuffer(
               CONTEXT86 *context /* [in] EDI register: pointer to buffer */
 ) {
     if (context->Edi)
     {
         DWORD *buffer = (DWORD *)context->Edi - 2;
 
         UnMapLS(buffer[1]);
 
         GlobalUnlock((HGLOBAL)buffer[0]);
         GlobalFree((HGLOBAL)buffer[0]);
     }
 }
 DEFINE_REGS_ENTRYPOINT( FreeMappedBuffer, 0 )
 
 /**********************************************************************
  *              GetTEBSelectorFS        (KERNEL.475)
  *      Set the 16-bit %fs to the 32-bit %fs (current TEB selector)
  */
 void WINAPI GetTEBSelectorFS16(void)
 {
     CURRENT_STACK16->fs = wine_get_fs();
 }
 
 /**********************************************************************
  *              IsPeFormat              (KERNEL.431)
  *
  * Determine if a file is a PE format executable.
  *
  * RETURNS
  *  TRUE, if it is.
  *  FALSE if the file could not be opened or is not a PE file.
  *
  * NOTES
  *  If fn is given as NULL then the function expects hf16 to be valid.
  */
 BOOL16 WINAPI IsPeFormat16(
         LPSTR   fn,     /* [in] Filename to the executable */
         HFILE16 hf16)   /* [in] An open file handle */
 {
     BOOL ret = FALSE;
     IMAGE_DOS_HEADER mzh;
     OFSTRUCT ofs;
     DWORD xmagic;
 
     if (fn) hf16 = OpenFile16(fn,&ofs,OF_READ);
     if (hf16 == HFILE_ERROR16) return FALSE;
     _llseek16(hf16,0,SEEK_SET);
     if (sizeof(mzh)!=_lread16(hf16,&mzh,sizeof(mzh))) goto done;
     if (mzh.e_magic!=IMAGE_DOS_SIGNATURE) goto done;
     _llseek16(hf16,mzh.e_lfanew,SEEK_SET);
     if (sizeof(DWORD)!=_lread16(hf16,&xmagic,sizeof(DWORD))) goto done;
     ret = (xmagic == IMAGE_NT_SIGNATURE);
  done:
     _lclose16(hf16);
     return ret;
 }
 
 
 /***********************************************************************
  *           K32Thk1632Prolog                   (KERNEL32.@)
  */
 void WINAPI __regs_K32Thk1632Prolog( CONTEXT86 *context )
 {
    LPBYTE code = (LPBYTE)context->Eip - 5;
 
    /* Arrrgh! SYSTHUNK.DLL just has to re-implement another method
       of 16->32 thunks instead of using one of the standard methods!
       This means that SYSTHUNK.DLL itself switches to a 32-bit stack,
       and does a far call to the 32-bit code segment of OLECLI32/OLESVR32.
       Unfortunately, our CallTo/CallFrom mechanism is therefore completely
       bypassed, which means it will crash the next time the 32-bit OLE
       code thunks down again to 16-bit (this *will* happen!).
 
       The following hack tries to recognize this situation.
       This is possible since the called stubs in OLECLI32/OLESVR32 all
       look exactly the same:
         00   E8xxxxxxxx    call K32Thk1632Prolog
         05   FF55FC        call [ebp-04]
         08   E8xxxxxxxx    call K32Thk1632Epilog
         0D   66CB          retf
 
       If we recognize this situation, we try to simulate the actions
       of our CallTo/CallFrom mechanism by copying the 16-bit stack
       to our 32-bit stack, creating a proper STACK16FRAME and
       updating cur_stack. */
 
    if (   code[5] == 0xFF && code[6] == 0x55 && code[7] == 0xFC
        && code[13] == 0x66 && code[14] == 0xCB)
    {
       DWORD argSize = context->Ebp - context->Esp;
       char *stack16 = (char *)context->Esp - 4;
       STACK16FRAME *frame16 = (STACK16FRAME *)stack16 - 1;
       STACK32FRAME *frame32 = NtCurrentTeb()->WOW32Reserved;
       char *stack32 = (char *)frame32 - argSize;
       WORD  stackSel  = SELECTOROF(frame32->frame16);
       DWORD stackBase = GetSelectorBase(stackSel);
 
       TRACE("before SYSTHUNK hack: EBP: %08x ESP: %08x cur_stack: %p\n",
             context->Ebp, context->Esp, NtCurrentTeb()->WOW32Reserved);
 
       memset(frame16, '\0', sizeof(STACK16FRAME));
       frame16->frame32 = frame32;
       frame16->ebp = context->Ebp;
 
       memcpy(stack32, stack16, argSize);
       NtCurrentTeb()->WOW32Reserved = (void *)MAKESEGPTR(stackSel, (DWORD)frame16 - stackBase);
 
       context->Esp = (DWORD)stack32 + 4;
       context->Ebp = context->Esp + argSize;
 
       TRACE("after  SYSTHUNK hack: EBP: %08x ESP: %08x cur_stack: %p\n",
             context->Ebp, context->Esp, NtCurrentTeb()->WOW32Reserved);
    }
 
     /* entry_point is never used again once the entry point has
        been called.  Thus we re-use it to hold the Win16Lock count */
    ReleaseThunkLock(&CURRENT_STACK16->entry_point);
 }
 DEFINE_REGS_ENTRYPOINT( K32Thk1632Prolog, 0 )
 
 /***********************************************************************
  *           K32Thk1632Epilog                   (KERNEL32.@)
  */
 void WINAPI __regs_K32Thk1632Epilog( CONTEXT86 *context )
 {
    LPBYTE code = (LPBYTE)context->Eip - 13;
 
    RestoreThunkLock(CURRENT_STACK16->entry_point);
 
    /* We undo the SYSTHUNK hack if necessary. See K32Thk1632Prolog. */
 
    if (   code[5] == 0xFF && code[6] == 0x55 && code[7] == 0xFC
        && code[13] == 0x66 && code[14] == 0xCB)
    {
       STACK16FRAME *frame16 = MapSL((SEGPTR)NtCurrentTeb()->WOW32Reserved);
       char *stack16 = (char *)(frame16 + 1);
       DWORD argSize = frame16->ebp - (DWORD)stack16;
       char *stack32 = (char *)frame16->frame32 - argSize;
 
       DWORD nArgsPopped = context->Esp - (DWORD)stack32;
 
       TRACE("before SYSTHUNK hack: EBP: %08x ESP: %08x cur_stack: %p\n",
             context->Ebp, context->Esp, NtCurrentTeb()->WOW32Reserved);
 
       NtCurrentTeb()->WOW32Reserved = frame16->frame32;
 
       context->Esp = (DWORD)stack16 + nArgsPopped;
       context->Ebp = frame16->ebp;
 
       TRACE("after  SYSTHUNK hack: EBP: %08x ESP: %08x cur_stack: %p\n",
             context->Ebp, context->Esp, NtCurrentTeb()->WOW32Reserved);
    }
 }
 DEFINE_REGS_ENTRYPOINT( K32Thk1632Epilog, 0 )
 
 /*********************************************************************
  *                   PK16FNF [KERNEL32.91]
  *
  *  This routine fills in the supplied 13-byte (8.3 plus terminator)
  *  string buffer with the 8.3 filename of a recently loaded 16-bit
  *  module.  It is unknown exactly what modules trigger this
  *  mechanism or what purpose this serves.  Win98 Explorer (and
  *  probably also Win95 with IE 4 shell integration) calls this
  *  several times during initialization.
  *
  *  FIXME: find out what this really does and make it work.
  */
 void WINAPI PK16FNF(LPSTR strPtr)
 {
        FIXME("(%p): stub\n", strPtr);
 
        /* fill in a fake filename that'll be easy to recognize */
        strcpy(strPtr, "WINESTUB.FIX");
 }
 
 /***********************************************************************
  * 16->32 Flat Thunk routines:
  */
 
 /***********************************************************************
  *              ThunkConnect16          (KERNEL.651)
  * Connects a 32bit and a 16bit thunkbuffer.
  */
 UINT WINAPI ThunkConnect16(
         LPSTR module16,              /* [in] name of win16 dll */
         LPSTR module32,              /* [in] name of win32 dll */
         HINSTANCE16 hInst16,         /* [in] hInst of win16 dll */
         DWORD dwReason,              /* [in] initialisation argument */
         struct ThunkDataCommon *TD,  /* [in/out] thunkbuffer */
         LPSTR thunkfun32,            /* [in] win32 thunkfunction */
         WORD cs                      /* [in] CS of win16 dll */
 ) {
     BOOL directionSL;
 
     if (!strncmp(TD->magic, "SL01", 4))
     {
         directionSL = TRUE;
 
         TRACE("SL01 thunk %s (%p) -> %s (%s), Reason: %d\n",
               module16, TD, module32, thunkfun32, dwReason);
     }
     else if (!strncmp(TD->magic, "LS01", 4))
     {
         directionSL = FALSE;
 
         TRACE("LS01 thunk %s (%p) <- %s (%s), Reason: %d\n",
               module16, TD, module32, thunkfun32, dwReason);
     }
     else
     {
         ERR("Invalid magic %c%c%c%c\n",
             TD->magic[0], TD->magic[1], TD->magic[2], TD->magic[3]);
         return 0;
     }
 
     switch (dwReason)
     {
         case DLL_PROCESS_ATTACH:
             if (directionSL)
             {
                 struct ThunkDataSL16 *SL16 = (struct ThunkDataSL16 *)TD;
                 struct ThunkDataSL   *SL   = SL16->fpData;
 
                 if (SL == NULL)
                 {
                     SL = HeapAlloc(GetProcessHeap(), 0, sizeof(*SL));
 
                     SL->common   = SL16->common;
                     SL->flags1   = SL16->flags1;
                     SL->flags2   = SL16->flags2;
 
                     SL->apiDB    = MapSL(SL16->apiDatabase);
                     SL->targetDB = NULL;
 
                     lstrcpynA(SL->pszDll16, module16, 255);
                     lstrcpynA(SL->pszDll32, module32, 255);
 
                     /* We should create a SEGPTR to the ThunkDataSL,
                        but since the contents are not in the original format,
                        any access to this by 16-bit code would crash anyway. */
                     SL16->spData = 0;
                     SL16->fpData = SL;
                 }
 
 
                 if (SL->flags2 & 0x80000000)
                 {
                     TRACE("Preloading 32-bit library\n");
                     LoadLibraryA(module32);
                 }
             }
             else
             {
                 /* nothing to do */
             }
             break;
 
         case DLL_PROCESS_DETACH:
             /* FIXME: cleanup */
             break;
     }
 
     return 1;
 }
 
 
 /***********************************************************************
  *           C16ThkSL                           (KERNEL.630)
  */
 
 void WINAPI C16ThkSL(CONTEXT86 *context)
 {
     LPBYTE stub = MapSL(context->Eax), x = stub;
     WORD cs = wine_get_cs();
     WORD ds = wine_get_ds();
 
     /* We produce the following code:
      *
      *   mov ax, __FLATDS
      *   mov es, ax
      *   movzx ecx, cx
      *   mov edx, es:[ecx + $EDX]
      *   push bp
      *   push edx
      *   push dx
      *   push edx
      *   call __FLATCS:__wine_call_from_16_thunk
      */
 
     *x++ = 0xB8; *(WORD *)x = ds; x += sizeof(WORD);
     *x++ = 0x8E; *x++ = 0xC0;
     *x++ = 0x66; *x++ = 0x0F; *x++ = 0xB7; *x++ = 0xC9;
     *x++ = 0x67; *x++ = 0x66; *x++ = 0x26; *x++ = 0x8B;
                  *x++ = 0x91; *(DWORD *)x = context->Edx; x += sizeof(DWORD);
 
     *x++ = 0x55;
     *x++ = 0x66; *x++ = 0x52;
     *x++ = 0x52;
     *x++ = 0x66; *x++ = 0x52;
     *x++ = 0x66; *x++ = 0x9A;
     *(void **)x = __wine_call_from_16_thunk; x += sizeof(void *);
     *(WORD *)x = cs; x += sizeof(WORD);
 
     /* Jump to the stub code just created */
     context->Eip = LOWORD(context->Eax);
     context->SegCs  = HIWORD(context->Eax);
 
     /* Since C16ThkSL got called by a jmp, we need to leave the
        original return address on the stack */
     context->Esp -= 4;
 }
 
 /***********************************************************************
  *           C16ThkSL01                         (KERNEL.631)
  */
 
 void WINAPI C16ThkSL01(CONTEXT86 *context)
 {
     LPBYTE stub = MapSL(context->Eax), x = stub;
 
     if (stub)
     {
         struct ThunkDataSL16 *SL16 = MapSL(context->Edx);
         struct ThunkDataSL *td = SL16->fpData;
 
         DWORD procAddress = (DWORD)GetProcAddress16(GetModuleHandle16("KERNEL"), (LPCSTR)631);
         WORD cs = wine_get_cs();
 
         if (!td)
         {
             ERR("ThunkConnect16 was not called!\n");
             return;
         }
 
         TRACE("Creating stub for ThunkDataSL %p\n", td);
 
 
         /* We produce the following code:
          *
          *   xor eax, eax
          *   mov edx, $td
          *   call C16ThkSL01
          *   push bp
          *   push edx
          *   push dx
          *   push edx
          *   call __FLATCS:__wine_call_from_16_thunk
          */
 
         *x++ = 0x66; *x++ = 0x33; *x++ = 0xC0;
         *x++ = 0x66; *x++ = 0xBA; *(void **)x = td; x += sizeof(void *);
         *x++ = 0x9A; *(DWORD *)x = procAddress; x += sizeof(DWORD);
 
         *x++ = 0x55;
         *x++ = 0x66; *x++ = 0x52;
         *x++ = 0x52;
         *x++ = 0x66; *x++ = 0x52;
         *x++ = 0x66; *x++ = 0x9A;
         *(void **)x = __wine_call_from_16_thunk; x += sizeof(void *);
         *(WORD *)x = cs; x += sizeof(WORD);
 
         /* Jump to the stub code just created */
         context->Eip = LOWORD(context->Eax);
         context->SegCs  = HIWORD(context->Eax);
 
         /* Since C16ThkSL01 got called by a jmp, we need to leave the
            original return address on the stack */
         context->Esp -= 4;
     }
     else
     {
         struct ThunkDataSL *td = (struct ThunkDataSL *)context->Edx;
         DWORD targetNr = LOWORD(context->Ecx) / 4;
         struct SLTargetDB *tdb;
 
         TRACE("Process %08x calling target %d of ThunkDataSL %p\n",
               GetCurrentProcessId(), targetNr, td);
 
         for (tdb = td->targetDB; tdb; tdb = tdb->next)
             if (tdb->process == GetCurrentProcessId())
                 break;
 
         if (!tdb)
         {
             TRACE("Loading 32-bit library %s\n", td->pszDll32);
             LoadLibraryA(td->pszDll32);
 
             for (tdb = td->targetDB; tdb; tdb = tdb->next)
                 if (tdb->process == GetCurrentProcessId())
                     break;
         }
 
         if (tdb)
         {
             context->Edx = tdb->targetTable[targetNr];
 
             TRACE("Call target is %08x\n", context->Edx);
         }
         else
         {
             WORD *stack = MapSL( MAKESEGPTR(context->SegSs, LOWORD(context->Esp)) );
             context->Edx = (context->Edx & ~0xffff) | HIWORD(td->apiDB[targetNr].errorReturnValue);
             context->Eax = (context->Eax & ~0xffff) | LOWORD(td->apiDB[targetNr].errorReturnValue);
             context->Eip = stack[2];
             context->SegCs  = stack[3];
             context->Esp += td->apiDB[targetNr].nrArgBytes + 4;
 
             ERR("Process %08x did not ThunkConnect32 %s to %s\n",
                 GetCurrentProcessId(), td->pszDll32, td->pszDll16);
         }
     }
 }
 
 
 /***********************************************************************
  * 16<->32 Thunklet/Callback API:
  */
 
 #include "pshpack1.h"
 typedef struct _THUNKLET
 {
     BYTE        prefix_target;
     BYTE        pushl_target;
     DWORD       target;
 
     BYTE        prefix_relay;
     BYTE        pushl_relay;
     DWORD       relay;
 
     BYTE        jmp_glue;
     DWORD       glue;
 
     BYTE        type;
     HINSTANCE16 owner;
     struct _THUNKLET *next;
 } THUNKLET;
 #include "poppack.h"
 
 #define THUNKLET_TYPE_LS  1
 #define THUNKLET_TYPE_SL  2
 
 static HANDLE  ThunkletHeap = 0;
 static WORD ThunkletCodeSel;
 static THUNKLET *ThunkletAnchor = NULL;
 
 static FARPROC ThunkletSysthunkGlueLS = 0;
 static SEGPTR    ThunkletSysthunkGlueSL = 0;
 
 static FARPROC ThunkletCallbackGlueLS = 0;
 static SEGPTR    ThunkletCallbackGlueSL = 0;
 
 
 /* map a thunk allocated on ThunkletHeap to a 16-bit pointer */
 static inline SEGPTR get_segptr( void *thunk )
 {
     if (!thunk) return 0;
     return MAKESEGPTR( ThunkletCodeSel, (char *)thunk - (char *)ThunkletHeap );
 }
 
 /***********************************************************************
  *           THUNK_Init
  */
 static BOOL THUNK_Init(void)
 {
     LPBYTE thunk;
 
     ThunkletHeap = HeapCreate( 0, 0x10000, 0x10000 );
     if (!ThunkletHeap) return FALSE;
 
     ThunkletCodeSel = SELECTOR_AllocBlock( ThunkletHeap, 0x10000, WINE_LDT_FLAGS_CODE );
 
     thunk = HeapAlloc( ThunkletHeap, 0, 5 );
     if (!thunk) return FALSE;
 
     ThunkletSysthunkGlueLS = (FARPROC)thunk;
     *thunk++ = 0x58;                             /* popl eax */
     *thunk++ = 0xC3;                             /* ret      */
 
     ThunkletSysthunkGlueSL = get_segptr( thunk );
     *thunk++ = 0x66; *thunk++ = 0x58;            /* popl eax */
     *thunk++ = 0xCB;                             /* lret     */
 
     return TRUE;
 }
 
 /***********************************************************************
  *     SetThunkletCallbackGlue             (KERNEL.560)
  */
 void WINAPI SetThunkletCallbackGlue16( FARPROC glueLS, SEGPTR glueSL )
 {
     ThunkletCallbackGlueLS = glueLS;
     ThunkletCallbackGlueSL = glueSL;
 }
 
 
 /***********************************************************************
  *     THUNK_FindThunklet
  */
 static THUNKLET *THUNK_FindThunklet( DWORD target, DWORD relay,
                                      DWORD glue, BYTE type )
 {
     THUNKLET *thunk;
 
     for (thunk = ThunkletAnchor; thunk; thunk = thunk->next)
         if (    thunk->type   == type
              && thunk->target == target
              && thunk->relay  == relay
              && ( type == THUNKLET_TYPE_LS ?
                     ( thunk->glue == glue - (DWORD)&thunk->type )
                   : ( thunk->glue == glue ) ) )
             return thunk;
 
      return NULL;
 }
 
 /***********************************************************************
  *     THUNK_AllocLSThunklet
  */
 static FARPROC THUNK_AllocLSThunklet( SEGPTR target, DWORD relay,
                                       FARPROC glue, HTASK16 owner )
 {
     THUNKLET *thunk = THUNK_FindThunklet( (DWORD)target, relay, (DWORD)glue,
                                           THUNKLET_TYPE_LS );
     if (!thunk)
     {
         TDB *pTask = GlobalLock16( owner );
 
         if (!ThunkletHeap) THUNK_Init();
         if ( !(thunk = HeapAlloc( ThunkletHeap, 0, sizeof(THUNKLET) )) )
             return 0;
 
         thunk->prefix_target = thunk->prefix_relay = 0x90;
         thunk->pushl_target  = thunk->pushl_relay  = 0x68;
         thunk->jmp_glue = 0xE9;
 
         thunk->target  = (DWORD)target;
         thunk->relay   = relay;
         thunk->glue    = (DWORD)glue - (DWORD)&thunk->type;
 
         thunk->type    = THUNKLET_TYPE_LS;
         thunk->owner   = pTask? pTask->hInstance : 0;
 
         thunk->next    = ThunkletAnchor;
         ThunkletAnchor = thunk;
     }
 
     return (FARPROC)thunk;
 }
 
 /***********************************************************************
  *     THUNK_AllocSLThunklet
  */
 static SEGPTR THUNK_AllocSLThunklet( FARPROC target, DWORD relay,
                                      SEGPTR glue, HTASK16 owner )
 {
     THUNKLET *thunk = THUNK_FindThunklet( (DWORD)target, relay, (DWORD)glue,
                                           THUNKLET_TYPE_SL );
     if (!thunk)
     {
         TDB *pTask = GlobalLock16( owner );
 
         if (!ThunkletHeap) THUNK_Init();
         if ( !(thunk = HeapAlloc( ThunkletHeap, 0, sizeof(THUNKLET) )) )
             return 0;
 
         thunk->prefix_target = thunk->prefix_relay = 0x66;
         thunk->pushl_target  = thunk->pushl_relay  = 0x68;
         thunk->jmp_glue = 0xEA;
 
         thunk->target  = (DWORD)target;
         thunk->relay   = relay;
         thunk->glue    = (DWORD)glue;
 
         thunk->type    = THUNKLET_TYPE_SL;
         thunk->owner   = pTask? pTask->hInstance : 0;
 
         thunk->next    = ThunkletAnchor;
         ThunkletAnchor = thunk;
     }
 
     return get_segptr( thunk );
 }
 
 /**********************************************************************
  *     IsLSThunklet
  */
 static BOOL16 IsLSThunklet( THUNKLET *thunk )
 {
     return    thunk->prefix_target == 0x90 && thunk->pushl_target == 0x68
            && thunk->prefix_relay  == 0x90 && thunk->pushl_relay  == 0x68
            && thunk->jmp_glue == 0xE9 && thunk->type == THUNKLET_TYPE_LS;
 }
 
 /**********************************************************************
  *     IsSLThunklet                        (KERNEL.612)
  */
 BOOL16 WINAPI IsSLThunklet16( THUNKLET *thunk )
 {
     return    thunk->prefix_target == 0x66 && thunk->pushl_target == 0x68
            && thunk->prefix_relay  == 0x66 && thunk->pushl_relay  == 0x68
            && thunk->jmp_glue == 0xEA && thunk->type == THUNKLET_TYPE_SL;
 }
 
 
 
 /***********************************************************************
  *     AllocLSThunkletSysthunk             (KERNEL.607)
  */
 FARPROC WINAPI AllocLSThunkletSysthunk16( SEGPTR target,
                                           FARPROC relay, DWORD dummy )
 {
     if (!ThunkletSysthunkGlueLS) THUNK_Init();
     return THUNK_AllocLSThunklet( (SEGPTR)relay, (DWORD)target,
                                   ThunkletSysthunkGlueLS, GetCurrentTask() );
 }
 
 /***********************************************************************
  *     AllocSLThunkletSysthunk             (KERNEL.608)
  */
 SEGPTR WINAPI AllocSLThunkletSysthunk16( FARPROC target,
                                        SEGPTR relay, DWORD dummy )
 {
     if (!ThunkletSysthunkGlueSL) THUNK_Init();
     return THUNK_AllocSLThunklet( (FARPROC)relay, (DWORD)target,
                                   ThunkletSysthunkGlueSL, GetCurrentTask() );
 }
 
 
 /***********************************************************************
  *     AllocLSThunkletCallbackEx           (KERNEL.567)
  */
 FARPROC WINAPI AllocLSThunkletCallbackEx16( SEGPTR target,
                                             DWORD relay, HTASK16 task )
 {
     THUNKLET *thunk = MapSL( target );
     if ( !thunk ) return NULL;
 
     if (   IsSLThunklet16( thunk ) && thunk->relay == relay
         && thunk->glue == (DWORD)ThunkletCallbackGlueSL )
         return (FARPROC)thunk->target;
 
     return THUNK_AllocLSThunklet( target, relay,
                                   ThunkletCallbackGlueLS, task );
 }
 
 /***********************************************************************
  *     AllocSLThunkletCallbackEx           (KERNEL.568)
  */
 SEGPTR WINAPI AllocSLThunkletCallbackEx16( FARPROC target,
                                          DWORD relay, HTASK16 task )
 {
     THUNKLET *thunk = (THUNKLET *)target;
     if ( !thunk ) return 0;
 
     if (   IsLSThunklet( thunk ) && thunk->relay == relay
         && thunk->glue == (DWORD)ThunkletCallbackGlueLS - (DWORD)&thunk->type )
         return (SEGPTR)thunk->target;
 
     return THUNK_AllocSLThunklet( target, relay,
                                   ThunkletCallbackGlueSL, task );
 }
 
 /***********************************************************************
  *     AllocLSThunkletCallback             (KERNEL.561)
  *     AllocLSThunkletCallback_dup         (KERNEL.606)
  */
 FARPROC WINAPI AllocLSThunkletCallback16( SEGPTR target, DWORD relay )
 {
     return AllocLSThunkletCallbackEx16( target, relay, GetCurrentTask() );
 }
 
 /***********************************************************************
  *     AllocSLThunkletCallback             (KERNEL.562)
  *     AllocSLThunkletCallback_dup         (KERNEL.605)
  */
 SEGPTR WINAPI AllocSLThunkletCallback16( FARPROC target, DWORD relay )
 {
     return AllocSLThunkletCallbackEx16( target, relay, GetCurrentTask() );
 }
 
 /***********************************************************************
  *     FindLSThunkletCallback              (KERNEL.563)
  *     FindLSThunkletCallback_dup          (KERNEL.609)
  */
 FARPROC WINAPI FindLSThunkletCallback( SEGPTR target, DWORD relay )
 {
     THUNKLET *thunk = MapSL( target );
     if (   thunk && IsSLThunklet16( thunk ) && thunk->relay == relay
         && thunk->glue == (DWORD)ThunkletCallbackGlueSL )
         return (FARPROC)thunk->target;
 
     thunk = THUNK_FindThunklet( (DWORD)target, relay,
                                 (DWORD)ThunkletCallbackGlueLS,
                                 THUNKLET_TYPE_LS );
     return (FARPROC)thunk;
 }
 
 /***********************************************************************
  *     FindSLThunkletCallback              (KERNEL.564)
  *     FindSLThunkletCallback_dup          (KERNEL.610)
  */
 SEGPTR WINAPI FindSLThunkletCallback( FARPROC target, DWORD relay )
 {
     THUNKLET *thunk = (THUNKLET *)target;
     if (   thunk && IsLSThunklet( thunk ) && thunk->relay == relay
         && thunk->glue == (DWORD)ThunkletCallbackGlueLS - (DWORD)&thunk->type )
         return (SEGPTR)thunk->target;
 
     thunk = THUNK_FindThunklet( (DWORD)target, relay,
                                 (DWORD)ThunkletCallbackGlueSL,
                                 THUNKLET_TYPE_SL );
     return get_segptr( thunk );
 }
 
 
 /***********************************************************************
  *     FreeThunklet            (KERNEL.611)
  */
 BOOL16 WINAPI FreeThunklet16( DWORD unused1, DWORD unused2 )
 {
     return FALSE;
 }
 
 
 /***********************************************************************
  * Callback Client API
  */
 
 #define N_CBC_FIXED    20
 #define N_CBC_VARIABLE 10
 #define N_CBC_TOTAL    (N_CBC_FIXED + N_CBC_VARIABLE)
 
 static SEGPTR CBClientRelay16[ N_CBC_TOTAL ];
 static FARPROC *CBClientRelay32[ N_CBC_TOTAL ];
 
 /***********************************************************************
  *     RegisterCBClient                    (KERNEL.619)
  */
 INT16 WINAPI RegisterCBClient16( INT16 wCBCId,
                                  SEGPTR relay16, FARPROC *relay32 )
 {
     /* Search for free Callback ID */
     if ( wCBCId == -1 )
         for ( wCBCId = N_CBC_FIXED; wCBCId < N_CBC_TOTAL; wCBCId++ )
             if ( !CBClientRelay16[ wCBCId ] )
                 break;
 
     /* Register Callback ID */
     if ( wCBCId > 0 && wCBCId < N_CBC_TOTAL )
     {
         CBClientRelay16[ wCBCId ] = relay16;
         CBClientRelay32[ wCBCId ] = relay32;
     }
     else
         wCBCId = 0;
 
     return wCBCId;
 }
 
 /***********************************************************************
  *     UnRegisterCBClient                  (KERNEL.622)
  */
 INT16 WINAPI UnRegisterCBClient16( INT16 wCBCId,
                                    SEGPTR relay16, FARPROC *relay32 )
 {
     if (    wCBCId >= N_CBC_FIXED && wCBCId < N_CBC_TOTAL
          && CBClientRelay16[ wCBCId ] == relay16
          && CBClientRelay32[ wCBCId ] == relay32 )
     {
         CBClientRelay16[ wCBCId ] = 0;
         CBClientRelay32[ wCBCId ] = 0;
     }
     else
         wCBCId = 0;
 
     return wCBCId;
 }
 
 
 /***********************************************************************
  *     InitCBClient                        (KERNEL.623)
  */
 void WINAPI InitCBClient16( FARPROC glueLS )
 {
     HMODULE16 kernel = GetModuleHandle16( "KERNEL" );
     SEGPTR glueSL = (SEGPTR)GetProcAddress16( kernel, (LPCSTR)604 );
 
     SetThunkletCallbackGlue16( glueLS, glueSL );
 }
 
 /***********************************************************************
  *     CBClientGlueSL                      (KERNEL.604)
  */
 void WINAPI CBClientGlueSL( CONTEXT86 *context )
 {
     /* Create stack frame */
     SEGPTR stackSeg = stack16_push( 12 );
     LPWORD stackLin = MapSL( stackSeg );
     SEGPTR glue, *glueTab;
 
     stackLin[3] = (WORD)context->Ebp;
     stackLin[2] = (WORD)context->Esi;
     stackLin[1] = (WORD)context->Edi;
     stackLin[0] = (WORD)context->SegDs;
 
     context->Ebp = OFFSETOF( stackSeg ) + 6;
     context->Esp = OFFSETOF( stackSeg ) - 4;
     context->SegGs = 0;
 
     /* Jump to 16-bit relay code */
     glueTab = MapSL( CBClientRelay16[ stackLin[5] ] );
     glue = glueTab[ stackLin[4] ];
     context->SegCs = SELECTOROF( glue );
     context->Eip   = OFFSETOF  ( glue );
 }
 
 /***********************************************************************
  *     CBClientThunkSL                      (KERNEL.620)
  */
 extern DWORD CALL32_CBClient( FARPROC proc, LPWORD args, WORD *stackLin, DWORD *esi );
 void WINAPI CBClientThunkSL( CONTEXT86 *context )
 {
     /* Call 32-bit relay code */
 
     LPWORD args = MapSL( MAKESEGPTR( context->SegSs, LOWORD(context->Ebp) ) );
     FARPROC proc = CBClientRelay32[ args[2] ][ args[1] ];
 
     /* fill temporary area for the asm code (see comments in winebuild) */
     SEGPTR stack = stack16_push( 12 );
     LPWORD stackLin = MapSL(stack);
     /* stackLin[0] and stackLin[1] reserved for the 32-bit stack ptr */
     stackLin[2] = wine_get_ss();
     stackLin[3] = 0;
     stackLin[4] = OFFSETOF(stack) + 12;
     stackLin[5] = SELECTOROF(stack);
     stackLin[6] = OFFSETOF(CALL32_CBClientEx_RetAddr);  /* overwrite return address */
     stackLin[7] = SELECTOROF(CALL32_CBClientEx_RetAddr);
     context->Eax = CALL32_CBClient( proc, args, stackLin + 4, &context->Esi );
     stack16_pop( 12 );
 }
 
 /***********************************************************************
  *     CBClientThunkSLEx                    (KERNEL.621)
  */
 extern DWORD CALL32_CBClientEx( FARPROC proc, LPWORD args, WORD *stackLin, DWORD *esi, INT *nArgs );
 void WINAPI CBClientThunkSLEx( CONTEXT86 *context )
 {
     /* Call 32-bit relay code */
 
     LPWORD args = MapSL( MAKESEGPTR( context->SegSs, LOWORD(context->Ebp) ) );
     FARPROC proc = CBClientRelay32[ args[2] ][ args[1] ];
     INT nArgs;
     LPWORD stackLin;
 
     /* fill temporary area for the asm code (see comments in winebuild) */
     SEGPTR stack = stack16_push( 24 );
     stackLin = MapSL(stack);
     stackLin[0] = OFFSETOF(stack) + 4;
     stackLin[1] = SELECTOROF(stack);
     stackLin[2] = wine_get_ds();
     stackLin[5] = OFFSETOF(stack) + 24;
     /* stackLin[6] and stackLin[7] reserved for the 32-bit stack ptr */
     stackLin[8] = wine_get_ss();
     stackLin[9] = 0;
     stackLin[10] = OFFSETOF(CALL32_CBClientEx_RetAddr);
     stackLin[11] = SELECTOROF(CALL32_CBClientEx_RetAddr);
 
     context->Eax = CALL32_CBClientEx( proc, args, stackLin, &context->Esi, &nArgs );
     stack16_pop( 24 );
 
     /* Restore registers saved by CBClientGlueSL */
     stackLin = (LPWORD)((LPBYTE)CURRENT_STACK16 + sizeof(STACK16FRAME) - 4);
     context->Ebp = (context->Ebp & ~0xffff) | stackLin[3];
     context->Esi = (context->Esi & ~0xffff) | stackLin[2];
     context->Edi = (context->Edi & ~0xffff) | stackLin[1];
     context->SegDs = stackLin[0];
     context->Esp += 16+nArgs;
 
     /* Return to caller of CBClient thunklet */
     context->SegCs = stackLin[9];
     context->Eip   = stackLin[8];
 }
 
 
 /***********************************************************************
  *           Get16DLLAddress       (KERNEL32.@)
  *
  * This function is used by a Win32s DLL if it wants to call a Win16 function.
  * A 16:16 segmented pointer to the function is returned.
  * Written without any docu.
  */
 SEGPTR WINAPI Get16DLLAddress(HMODULE16 handle, LPSTR func_name)
 {
     static WORD code_sel32;
     FARPROC16 proc_16;
     LPBYTE thunk;
 
     if (!code_sel32)
     {
         if (!ThunkletHeap) THUNK_Init();
         code_sel32 = SELECTOR_AllocBlock( ThunkletHeap, 0x10000,
                                           WINE_LDT_FLAGS_CODE | WINE_LDT_FLAGS_32BIT );
         if (!code_sel32) return 0;
     }
     if (!(thunk = HeapAlloc( ThunkletHeap, 0, 32 ))) return 0;
 
     if (!handle) handle = GetModuleHandle16("WIN32S16");
     proc_16 = GetProcAddress16(handle, func_name);
 
     /* movl proc_16, $edx */
     *thunk++ = 0xba;
     *(FARPROC16 *)thunk = proc_16;
     thunk += sizeof(FARPROC16);
 
      /* jmpl QT_Thunk */
     *thunk++ = 0xea;
     *(FARPROC *)thunk = GetProcAddress(kernel32_handle,"QT_Thunk");
     thunk += sizeof(FARPROC16);
     *(WORD *)thunk = wine_get_cs();
 
     return MAKESEGPTR( code_sel32, (char *)thunk - (char *)ThunkletHeap );
 }
 
 
 /***********************************************************************
  *              GetWin16DOSEnv                  (KERNEL32.34)
  * Returns some internal value.... probably the default environment database?
  */
 DWORD WINAPI GetWin16DOSEnv(void)
 {
         FIXME("stub, returning 0\n");
         return 0;
 }
 
 /**********************************************************************
  *           GetPK16SysVar    (KERNEL32.92)
  */
 LPVOID WINAPI GetPK16SysVar(void)
 {
     static BYTE PK16SysVar[128];
 
     FIXME("()\n");
     return PK16SysVar;
 }
 
 /**********************************************************************
  *           CommonUnimpStub    (KERNEL32.17)
  */
 void WINAPI __regs_CommonUnimpStub( CONTEXT86 *context )
 {
     FIXME("generic stub: %s\n", ((LPSTR)context->Eax ? (LPSTR)context->Eax : "?"));
 
     switch ((context->Ecx >> 4) & 0x0f)
     {
     case 15:  context->Eax = -1;   break;
     case 14:  context->Eax = 0x78; break;
     case 13:  context->Eax = 0x32; break;
     case 1:   context->Eax = 1;    break;
     default:  context->Eax = 0;    break;
     }
 
     context->Esp += (context->Ecx & 0x0f) * 4;
 }
 DEFINE_REGS_ENTRYPOINT( CommonUnimpStub, 0 )
 
 /**********************************************************************
  *           HouseCleanLogicallyDeadHandles    (KERNEL32.33)
  */
 void WINAPI HouseCleanLogicallyDeadHandles(void)
 {
     /* Whatever this is supposed to do, our handles probably
        don't need it :-) */
 }
 
 /**********************************************************************
  *              @ (KERNEL32.100)
  */
 BOOL WINAPI _KERNEL32_100(HANDLE threadid,DWORD exitcode,DWORD x)
 {
         FIXME("(%p,%d,0x%08x): stub\n",threadid,exitcode,x);
         return TRUE;
 }
 
 /**********************************************************************
  *              @ (KERNEL32.99)
  *
  * Checks whether the clock has to be switched from daylight
  * savings time to standard time or vice versa.
  *
  */
 DWORD WINAPI _KERNEL32_99(DWORD x)
 {
         FIXME("(0x%08x): stub\n",x);
         return 1;
 }
 
 
 /**********************************************************************
  *           Catch    (KERNEL.55)
  *
  * Real prototype is:
  *   INT16 WINAPI Catch( LPCATCHBUF lpbuf );
  */
 void WINAPI Catch16( LPCATCHBUF lpbuf, CONTEXT86 *context )
 {
     /* Note: we don't save the current ss, as the catch buffer is */
     /* only 9 words long. Hopefully no one will have the silly    */
     /* idea to change the current stack before calling Throw()... */
 
     /* Windows uses:
      * lpbuf[0] = ip
      * lpbuf[1] = cs
      * lpbuf[2] = sp
      * lpbuf[3] = bp
      * lpbuf[4] = si
      * lpbuf[5] = di
      * lpbuf[6] = ds
      * lpbuf[7] = unused
      * lpbuf[8] = ss
      */
 
     lpbuf[0] = LOWORD(context->Eip);
     lpbuf[1] = context->SegCs;
     /* Windows pushes 4 more words before saving sp */
     lpbuf[2] = LOWORD(context->Esp) - 4 * sizeof(WORD);
     lpbuf[3] = LOWORD(context->Ebp);
     lpbuf[4] = LOWORD(context->Esi);
     lpbuf[5] = LOWORD(context->Edi);
     lpbuf[6] = context->SegDs;
     lpbuf[7] = 0;
     lpbuf[8] = context->SegSs;
     context->Eax &= ~0xffff;  /* Return 0 */
 }
 
 
 /**********************************************************************
  *           Throw    (KERNEL.56)
  *
  * Real prototype is:
  *   INT16 WINAPI Throw( LPCATCHBUF lpbuf, INT16 retval );
  */
 void WINAPI Throw16( LPCATCHBUF lpbuf, INT16 retval, CONTEXT86 *context )
 {
     STACK16FRAME *pFrame;
     STACK32FRAME *frame32;
 
     context->Eax = (context->Eax & ~0xffff) | (WORD)retval;
 
     /* Find the frame32 corresponding to the frame16 we are jumping to */
     pFrame = CURRENT_STACK16;
     frame32 = pFrame->frame32;
     while (frame32 && frame32->frame16)
     {
         if (OFFSETOF(frame32->frame16) < OFFSETOF(NtCurrentTeb()->WOW32Reserved))
             break;  /* Something strange is going on */
         if (OFFSETOF(frame32->frame16) > lpbuf[2])
         {
             /* We found the right frame */
             pFrame->frame32 = frame32;
             break;
         }
         frame32 = ((STACK16FRAME *)MapSL(frame32->frame16))->frame32;
     }
     RtlUnwind( &pFrame->frame32->frame, NULL, NULL, 0 );
 
     context->Eip = lpbuf[0];
     context->SegCs  = lpbuf[1];
     context->Esp = lpbuf[2] + 4 * sizeof(WORD) - sizeof(WORD) /*extra arg*/;
     context->Ebp = lpbuf[3];
     context->Esi = lpbuf[4];
     context->Edi = lpbuf[5];
     context->SegDs  = lpbuf[6];
 
     if (lpbuf[8] != context->SegSs)
         ERR("Switching stack segment with Throw() not supported; expect crash now\n" );
 }
 
 
 /*
  *  16-bit WOW routines (in KERNEL)
  */
 
 /**********************************************************************
  *           GetVDMPointer32W      (KERNEL.516)
  */
 DWORD WINAPI GetVDMPointer32W16( SEGPTR vp, UINT16 fMode )
 {
     GlobalPageLock16(GlobalHandle16(SELECTOROF(vp)));
     return (DWORD)K32WOWGetVDMPointer( vp, 0, (DWORD)fMode );
 }
 
 /***********************************************************************
  *           LoadLibraryEx32W      (KERNEL.513)
  */
 DWORD WINAPI LoadLibraryEx32W16( LPCSTR lpszLibFile, DWORD hFile, DWORD dwFlags )
 {
     HMODULE hModule;
     DWORD mutex_count;
     OFSTRUCT ofs;
     const char *p;
 
     if (!lpszLibFile)
     {
         SetLastError(ERROR_INVALID_PARAMETER);
         return 0;
     }
 
     /* if the file cannot be found, call LoadLibraryExA anyway, since it might be
        a builtin module. This case is handled in MODULE_LoadLibraryExA */
 
     if ((p = strrchr( lpszLibFile, '.' )) && !strchr( p, '\\' ))  /* got an extension */
     {
         if (OpenFile16( lpszLibFile, &ofs, OF_EXIST ) != HFILE_ERROR16)
             lpszLibFile = ofs.szPathName;
     }
     else
     {
         char buffer[MAX_PATH+4];
         strcpy( buffer, lpszLibFile );
         strcat( buffer, ".dll" );
         if (OpenFile16( buffer, &ofs, OF_EXIST ) != HFILE_ERROR16)
             lpszLibFile = ofs.szPathName;
     }
 
     ReleaseThunkLock( &mutex_count );
     hModule = LoadLibraryExA( lpszLibFile, (HANDLE)hFile, dwFlags );
     RestoreThunkLock( mutex_count );
 
     return (DWORD)hModule;
 }
 
 /***********************************************************************
  *           GetProcAddress32W     (KERNEL.515)
  */
 DWORD WINAPI GetProcAddress32W16( DWORD hModule, LPCSTR lpszProc )
 {
     return (DWORD)GetProcAddress( (HMODULE)hModule, lpszProc );
 }
 
 /***********************************************************************
  *           FreeLibrary32W        (KERNEL.514)
  */
 DWORD WINAPI FreeLibrary32W16( DWORD hLibModule )
 {
     BOOL retv;
     DWORD mutex_count;
 
     ReleaseThunkLock( &mutex_count );
     retv = FreeLibrary( (HMODULE)hLibModule );
     RestoreThunkLock( mutex_count );
     return (DWORD)retv;
 }
 
 
 #define CPEX_DEST_STDCALL   0x00000000
 #define CPEX_DEST_CDECL     0x80000000
 
 /**********************************************************************
  *           WOW_CallProc32W
  */
 static DWORD WOW_CallProc32W16( FARPROC proc32, DWORD nrofargs, DWORD *args )
 {
     DWORD ret;
     DWORD mutex_count;
 
     ReleaseThunkLock( &mutex_count );
 
     /*
      * FIXME:  If ( nrofargs & CPEX_DEST_CDECL ) != 0, we should call a
      *         32-bit CDECL routine ...
      */
 
     if (!proc32) ret = 0;
     else switch (nrofargs)
     {
     case 0: ret = proc32();
             break;
     case 1: ret = proc32(args[0]);
             break;
     case 2: ret = proc32(args[0],args[1]);
             break;
     case 3: ret = proc32(args[0],args[1],args[2]);
             break;
     case 4: ret = proc32(args[0],args[1],args[2],args[3]);
             break;
     case 5: ret = proc32(args[0],args[1],args[2],args[3],args[4]);
             break;
     case 6: ret = proc32(args[0],args[1],args[2],args[3],args[4],args[5]);
             break;
     case 7: ret = proc32(args[0],args[1],args[2],args[3],args[4],args[5],args[6]);
             break;
     case 8: ret = proc32(args[0],args[1],args[2],args[3],args[4],args[5],args[6],args[7]);
             break;
     case 9: ret = proc32(args[0],args[1],args[2],args[3],args[4],args[5],args[6],args[7],args[8]);
             break;
     case 10:ret = proc32(args[0],args[1],args[2],args[3],args[4],args[5],args[6],args[7],args[8],args[9]);
             break;
     case 11:ret = proc32(args[0],args[1],args[2],args[3],args[4],args[5],args[6],args[7],args[8],args[9],args[10]);
             break;
     case 12:ret = proc32(args[0],args[1],args[2],args[3],args[4],args[5],args[6],args[7],args[8],args[9],args[10],args[11]);
             break;
     case 13:ret = proc32(args[0],args[1],args[2],args[3],args[4],args[5],args[6],args[7],args[8],args[9],args[10],args[11],args[12]);
             break;
     case 14:ret = proc32(args[0],args[1],args[2],args[3],args[4],args[5],args[6],args[7],args[8],args[9],args[10],args[11],args[12],args[13]);
             break;
     case 15:ret = proc32(args[0],args[1],args[2],args[3],args[4],args[5],args[6],args[7],args[8],args[9],args[10],args[11],args[12],args[13],args[14]);
             break;
     default:
             /* FIXME: should go up to 32  arguments */
             ERR("Unsupported number of arguments %d, please report.\n",nrofargs);
             ret = 0;
             break;
     }
 
     RestoreThunkLock( mutex_count );
 
     TRACE("returns %08x\n",ret);
     return ret;
 }
 
 /**********************************************************************
  *           CallProc32W           (KERNEL.517)
  */
 DWORD WINAPIV CallProc32W16( DWORD nrofargs, DWORD argconvmask, FARPROC proc32, VA_LIST16 valist )
 {
     DWORD args[32];
     unsigned int i;
 
     TRACE("(%d,%d,%p args[",nrofargs,argconvmask,proc32);
 
     for (i=0;i<nrofargs;i++)
     {
         if (argconvmask & (1<<i))
         {
             SEGPTR ptr = VA_ARG16( valist, SEGPTR );
             /* pascal convention, have to reverse the arguments order */
             args[nrofargs - i - 1] = (DWORD)MapSL(ptr);
             TRACE("%08x(%p),",ptr,MapSL(ptr));
         }
         else
         {
             DWORD arg = VA_ARG16( valist, DWORD );
             /* pascal convention, have to reverse the arguments order */
             args[nrofargs - i - 1] = arg;
             TRACE("%d,", arg);
         }
     }
     TRACE("])\n");
 
     /* POP nrofargs DWORD arguments and 3 DWORD parameters */
     stack16_pop( (3 + nrofargs) * sizeof(DWORD) );
 
     return WOW_CallProc32W16( proc32, nrofargs, args );
 }
 
 /**********************************************************************
  *           _CallProcEx32W         (KERNEL.518)
  */
 DWORD WINAPIV CallProcEx32W16( DWORD nrofargs, DWORD argconvmask, FARPROC proc32, VA_LIST16 valist )
 {
     DWORD args[32];
     unsigned int i;
 
     TRACE("(%d,%d,%p args[",nrofargs,argconvmask,proc32);
 
     for (i=0;i<nrofargs;i++)
     {
         if (argconvmask & (1<<i))
         {
             SEGPTR ptr = VA_ARG16( valist, SEGPTR );
             args[i] = (DWORD)MapSL(ptr);
             TRACE("%08x(%p),",ptr,MapSL(ptr));
         }
         else
         {
             DWORD arg = VA_ARG16( valist, DWORD );
             args[i] = arg;
             TRACE("%d,", arg);
         }
     }
     TRACE("])\n");
     return WOW_CallProc32W16( proc32, nrofargs, args );
 }
 
 
 /**********************************************************************
  *           WOW16Call               (KERNEL.500)
  *
  * FIXME!!!
  *
  */
 DWORD WINAPIV WOW16Call(WORD x, WORD y, WORD z, VA_LIST16 args)
 {
         int     i;
         DWORD   calladdr;
         FIXME("(0x%04x,0x%04x,%d),calling (",x,y,z);
 
         for (i=0;i<x/2;i++) {
                 WORD    a = VA_ARG16(args,WORD);
                 DPRINTF("%04x ",a);
         }
         calladdr = VA_ARG16(args,DWORD);
         stack16_pop( 3*sizeof(WORD) + x + sizeof(DWORD) );
         DPRINTF(") calling address was 0x%08x\n",calladdr);
         return 0;
 }
 
 #endif /* __i386__ */