git.oblomov.eu Git - wine/blob - if1632/thunk.c

   1 /*
   2  * Emulator thunks
   3  *
   4  * Copyright 1996, 1997 Alexandre Julliard
   5  * Copyright 1998       Ulrich Weigand
   6  */
   7
   8 #include <string.h>
   9 #include "wine/winbase16.h"
  10 #include "task.h"
  11 #include "hook.h"
  12 #include "callback.h"
  13 #include "builtin16.h"
  14 #include "heap.h"
  15 #include "neexe.h"
  16 #include "process.h"
  17 #include "stackframe.h"
  18 #include "win.h"
  19 #include "flatthunk.h"
  20 #include "selectors.h"
  21 #include "keyboard.h"
  22 #include "debugtools.h"
  23
  24 DEFAULT_DEBUG_CHANNEL(thunk)
  25
  26
  27 /* List of the 16-bit callback functions. This list is used  */
  28 /* by the build program to generate the file if1632/callto16.S */
  29
  30 /* ### start build ### */
  31 extern WORD CALLBACK THUNK_CallTo16_word_     (FARPROC16);
  32 extern WORD CALLBACK THUNK_CallTo16_word_w    (FARPROC16,WORD);
  33 extern WORD CALLBACK THUNK_CallTo16_word_l    (FARPROC16,LONG);
  34 extern LONG CALLBACK THUNK_CallTo16_long_l    (FARPROC16,LONG);
  35 extern WORD CALLBACK THUNK_CallTo16_word_ww   (FARPROC16,WORD,WORD);
  36 extern LONG CALLBACK THUNK_CallTo16_long_ll   (FARPROC16,LONG,LONG);
  37 extern WORD CALLBACK THUNK_CallTo16_word_www  (FARPROC16,WORD,WORD,WORD);
  38 extern WORD CALLBACK THUNK_CallTo16_word_lllw (FARPROC16,LONG,LONG,LONG,WORD);
  39 extern WORD CALLBACK THUNK_CallTo16_word_lwww (FARPROC16,LONG,WORD,WORD,WORD);
  40 extern WORD CALLBACK THUNK_CallTo16_word_wlww (FARPROC16,WORD,LONG,WORD,WORD);
  41 extern WORD CALLBACK THUNK_CallTo16_word_wwwl (FARPROC16,WORD,WORD,WORD,LONG);
  42 extern LONG CALLBACK THUNK_CallTo16_long_wwwl (FARPROC16,WORD,WORD,WORD,LONG);
  43 extern WORD CALLBACK THUNK_CallTo16_word_lwwww(FARPROC16,LONG,WORD,WORD,WORD,WORD);
  44 /* ### stop build ### */
  45
  46 static THUNK *firstThunk = NULL;
  47
  48 static BOOL THUNK_ThunkletInit( void );
  49
  50 /* Callbacks function table for the emulator */
  51 static const CALLBACKS_TABLE CALLBACK_EmulatorTable =
  52 {
  53     (void *)CallTo16RegisterShort,               /* CallRegisterShortProc */
  54     (void *)CallTo16RegisterLong,                /* CallRegisterLongProc */
  55     (void *)THUNK_CallTo16_word_w,               /* CallWindowsExitProc */
  56     (void *)THUNK_CallTo16_word_lwww,            /* CallWordBreakProc */
  57     (void *)THUNK_CallTo16_word_ww,              /* CallBootAppProc */
  58     (void *)THUNK_CallTo16_word_www,             /* CallLoadAppSegProc */
  59     (void *)THUNK_CallTo16_word_www,             /* CallLocalNotifyFunc */
  60     (void *)THUNK_CallTo16_word_www,             /* CallResourceHandlerProc */
  61     (void *)THUNK_CallTo16_long_ll,              /* CallUTProc */
  62     (void *)THUNK_CallTo16_long_l                /* CallASPIPostProc */
  63 };
  64
  65 const CALLBACKS_TABLE *Callbacks = &CALLBACK_EmulatorTable;
  66
  67 CALLOUT_TABLE Callout = { 0 };
  68
  69
  70 /***********************************************************************
  71  *           THUNK_Init
  72  */
  73 BOOL THUNK_Init(void)
  74 {
  75     /* Initialize Thunklets */
  76     return THUNK_ThunkletInit();
  77 }
  78
  79 /***********************************************************************
  80  *           THUNK_Alloc
  81  */
  82 FARPROC THUNK_Alloc( FARPROC16 func, RELAY relay )
  83 {
  84     HANDLE16 hSeg;
  85     NE_MODULE *pModule;
  86     THUNK *thunk;
  87
  88     /* NULL maps to NULL */
  89     if ( !func ) return NULL;
  90
  91     /*
  92      * If we got an 16-bit built-in API entry point, retrieve the Wine
  93      * 32-bit handler for that API routine.
  94      *
  95      * NOTE: For efficiency reasons, we only check whether the selector
  96      *       of 'func' points to the code segment of a built-in module.
  97      *       It might be theoretically possible that the offset is such
  98      *       that 'func' does not point, in fact, to an API entry point.
  99      *       In this case, however, the pointer is corrupt anyway.
 100      */
 101     hSeg = GlobalHandle16( SELECTOROF( func ) );
 102     pModule = NE_GetPtr( FarGetOwner16( hSeg ) );
 103
 104     if ( pModule && (pModule->flags & NE_FFLAGS_BUILTIN)
 105                  && NE_SEG_TABLE(pModule)[0].hSeg == hSeg )
 106     {
 107         FARPROC proc = (FARPROC)((ENTRYPOINT16 *)PTR_SEG_TO_LIN( func ))->target;
 108
 109         TRACE( "(%04x:%04x, %p) -> built-in API %p\n",
 110                SELECTOROF( func ), OFFSETOF( func ), relay, proc );
 111         return proc;
 112     }
 113
 114     /* Otherwise, we need to alloc a thunk */
 115     thunk = HeapAlloc( GetProcessHeap(), 0, sizeof(*thunk) );
 116     if (thunk)
 117     {
 118         thunk->popl_eax   = 0x58;
 119         thunk->pushl_func = 0x68;
 120         thunk->proc       = func;
 121         thunk->pushl_eax  = 0x50;
 122         thunk->jmp        = 0xe9;
 123         thunk->relay      = (RELAY)((char *)relay - (char *)(&thunk->next));
 124         thunk->magic      = CALLTO16_THUNK_MAGIC;
 125         thunk->next       = firstThunk;
 126         firstThunk = thunk;
 127     }
 128
 129     TRACE( "(%04x:%04x, %p) -> allocated thunk %p\n",
 130            SELECTOROF( func ), OFFSETOF( func ), relay, thunk );
 131     return (FARPROC)thunk;
 132 }
 133
 134 /***********************************************************************
 135  *           THUNK_Free
 136  */
 137 void THUNK_Free( FARPROC thunk )
 138 {
 139     THUNK *t = (THUNK*)thunk;
 140     if ( !t || IsBadReadPtr( t, sizeof(*t) )
 141             || t->magic != CALLTO16_THUNK_MAGIC )
 142          return;
 143
 144     if (HEAP_IsInsideHeap( GetProcessHeap(), 0, t ))
 145     {
 146         THUNK **prev = &firstThunk;
 147         while (*prev && (*prev != t)) prev = &(*prev)->next;
 148         if (*prev)
 149         {
 150             *prev = t->next;
 151             HeapFree( GetProcessHeap(), 0, t );
 152             return;
 153         }
 154     }
 155     ERR("invalid thunk addr %p\n", thunk );
 156     return;
 157 }
 158
 159
 160 /***********************************************************************
 161  *           THUNK_GetCalloutThunk
 162  *
 163  * Retrieve API entry point with given name from given module.
 164  * If module is builtin, return the 32-bit entry point, otherwise
 165  * create a 32->16 thunk to the 16-bit entry point, using the
 166  * given relay code.
 167  *
 168  */
 169 static FARPROC THUNK_GetCalloutThunk( NE_MODULE *pModule, LPSTR name, RELAY relay )
 170 {
 171     FARPROC16 proc = WIN32_GetProcAddress16( pModule->self, name );
 172     if ( !proc ) return 0;
 173
 174     if ( pModule->flags & NE_FFLAGS_BUILTIN )
 175         return (FARPROC)((ENTRYPOINT16 *)PTR_SEG_TO_LIN( proc ))->target;
 176     else
 177         return (FARPROC)THUNK_Alloc( proc, relay );
 178 }
 179
 180 /***********************************************************************
 181  *           THUNK_InitCallout
 182  */
 183 void THUNK_InitCallout(void)
 184 {
 185     HMODULE hModule;
 186     NE_MODULE *pModule;
 187
 188     hModule = GetModuleHandleA( "USER32" );
 189     if ( hModule )
 190     {
 191 #define GETADDR( name )  \
 192         *(FARPROC *)&Callout.##name = GetProcAddress( hModule, #name )
 193
 194         GETADDR( PeekMessageA );
 195         GETADDR( PeekMessageW );
 196         GETADDR( GetMessageA );
 197         GETADDR( GetMessageW );
 198         GETADDR( SendMessageA );
 199         GETADDR( SendMessageW );
 200         GETADDR( PostMessageA );
 201         GETADDR( PostMessageW );
 202         GETADDR( PostThreadMessageA );
 203         GETADDR( PostThreadMessageW );
 204         GETADDR( TranslateMessage );
 205         GETADDR( DispatchMessageW );
 206         GETADDR( DispatchMessageA );
 207         GETADDR( RedrawWindow );
 208         GETADDR( WaitForInputIdle );
 209         GETADDR( MessageBoxA );
 210         GETADDR( MessageBoxW );
 211 #undef GETADDR
 212     }
 213
 214     pModule = NE_GetPtr( GetModuleHandle16( "USER" ) );
 215     if ( pModule )
 216     {
 217 #define GETADDR( var, name, thk )  \
 218         *(FARPROC *)&Callout.##var = THUNK_GetCalloutThunk( pModule, name, \
 219                                                  (RELAY)THUNK_CallTo16_##thk )
 220
 221         GETADDR( PeekMessage16, "PeekMessage", word_lwwww );
 222         GETADDR( GetMessage16, "GetMessage", word_lwww );
 223         GETADDR( SendMessage16, "SendMessage", long_wwwl );
 224         GETADDR( PostMessage16, "PostMessage", word_wwwl );
 225         GETADDR( PostAppMessage16, "PostAppMessage", word_wwwl );
 226         GETADDR( TranslateMessage16, "TranslateMessage", word_l );
 227         GETADDR( DispatchMessage16, "DispatchMessage", long_l );
 228         GETADDR( RedrawWindow16, "RedrawWindow", word_wlww );
 229         GETADDR( FinalUserInit16, "FinalUserInit", word_ );
 230         GETADDR( InitApp16, "InitApp", word_w );
 231         GETADDR( InitThreadInput16, "InitThreadInput", word_ww );
 232         GETADDR( UserYield16, "UserYield", word_ );
 233         GETADDR( DestroyIcon32, "DestroyIcon32", word_ww );
 234         GETADDR( UserSignalProc, "SignalProc32", word_lllw );
 235
 236 #undef GETADDR
 237     }
 238 }
 239
 240 /***********************************************************************
 241  * 16->32 Flat Thunk routines:
 242  */
 243
 244 /***********************************************************************
 245  *              ThunkConnect16          (KERNEL.651)
 246  * Connects a 32bit and a 16bit thunkbuffer.
 247  */
 248 UINT WINAPI ThunkConnect16(
 249         LPSTR module16,              /* [in] name of win16 dll */
 250         LPSTR module32,              /* [in] name of win32 dll */
 251         HINSTANCE16 hInst16,         /* [in] hInst of win16 dll */
 252         DWORD dwReason,              /* [in] initialisation argument */
 253         struct ThunkDataCommon *TD,  /* [in/out] thunkbuffer */
 254         LPSTR thunkfun32,            /* [in] win32 thunkfunction */
 255         WORD cs                      /* [in] CS of win16 dll */
 256 ) {
 257     BOOL directionSL;
 258
 259     if (!strncmp(TD->magic, "SL01", 4))
 260     {
 261         directionSL = TRUE;
 262
 263         TRACE("SL01 thunk %s (%lx) -> %s (%s), Reason: %ld\n",
 264               module16, (DWORD)TD, module32, thunkfun32, dwReason);
 265     }
 266     else if (!strncmp(TD->magic, "LS01", 4))
 267     {
 268         directionSL = FALSE;
 269
 270         TRACE("LS01 thunk %s (%lx) <- %s (%s), Reason: %ld\n",
 271               module16, (DWORD)TD, module32, thunkfun32, dwReason);
 272     }
 273     else
 274     {
 275         ERR("Invalid magic %c%c%c%c\n",
 276             TD->magic[0], TD->magic[1], TD->magic[2], TD->magic[3]);
 277         return 0;
 278     }
 279
 280     switch (dwReason)
 281     {
 282         case DLL_PROCESS_ATTACH:
 283             if (directionSL)
 284             {
 285                 struct ThunkDataSL16 *SL16 = (struct ThunkDataSL16 *)TD;
 286                 struct ThunkDataSL   *SL   = SL16->fpData;
 287
 288                 if (SL == NULL)
 289                 {
 290                     SL = HeapAlloc(GetProcessHeap(), 0, sizeof(*SL));
 291
 292                     SL->common   = SL16->common;
 293                     SL->flags1   = SL16->flags1;
 294                     SL->flags2   = SL16->flags2;
 295
 296                     SL->apiDB    = PTR_SEG_TO_LIN(SL16->apiDatabase);
 297                     SL->targetDB = NULL;
 298
 299                     lstrcpynA(SL->pszDll16, module16, 255);
 300                     lstrcpynA(SL->pszDll32, module32, 255);
 301
 302                     /* We should create a SEGPTR to the ThunkDataSL,
 303                        but since the contents are not in the original format,
 304                        any access to this by 16-bit code would crash anyway. */
 305                     SL16->spData = 0;
 306                     SL16->fpData = SL;
 307                 }
 308
 309
 310                 if (SL->flags2 & 0x80000000)
 311                 {
 312                     TRACE("Preloading 32-bit library\n");
 313                     LoadLibraryA(module32);
 314                 }
 315             }
 316             else
 317             {
 318                 /* nothing to do */
 319             }
 320             break;
 321
 322         case DLL_PROCESS_DETACH:
 323             /* FIXME: cleanup */
 324             break;
 325     }
 326
 327     return 1;
 328 }
 329
 330
 331 /***********************************************************************
 332  *           C16ThkSL                           (KERNEL.630)
 333  */
 334
 335 void WINAPI C16ThkSL(CONTEXT86 *context)
 336 {
 337     LPBYTE stub = PTR_SEG_TO_LIN(EAX_reg(context)), x = stub;
 338     WORD cs = __get_cs();
 339     WORD ds = __get_ds();
 340
 341     /* We produce the following code:
 342      *
 343      *   mov ax, __FLATDS
 344      *   mov es, ax
 345      *   movzx ecx, cx
 346      *   mov edx, es:[ecx + $EDX]
 347      *   push bp
 348      *   push edx
 349      *   push dx
 350      *   push edx
 351      *   call __FLATCS:CallFrom16Thunk
 352      */
 353
 354     *x++ = 0xB8; *((WORD *)x)++ = ds;
 355     *x++ = 0x8E; *x++ = 0xC0;
 356     *x++ = 0x66; *x++ = 0x0F; *x++ = 0xB7; *x++ = 0xC9;
 357     *x++ = 0x67; *x++ = 0x66; *x++ = 0x26; *x++ = 0x8B;
 358                  *x++ = 0x91; *((DWORD *)x)++ = EDX_reg(context);
 359
 360     *x++ = 0x55;
 361     *x++ = 0x66; *x++ = 0x52;
 362     *x++ = 0x52;
 363     *x++ = 0x66; *x++ = 0x52;
 364     *x++ = 0x66; *x++ = 0x9A; *((DWORD *)x)++ = (DWORD)CallFrom16Thunk;
 365                               *((WORD *)x)++ = cs;
 366
 367     /* Jump to the stub code just created */
 368     EIP_reg(context) = LOWORD(EAX_reg(context));
 369     CS_reg(context)  = HIWORD(EAX_reg(context));
 370
 371     /* Since C16ThkSL got called by a jmp, we need to leave the
 372        original return address on the stack */
 373     ESP_reg(context) -= 4;
 374 }
 375
 376 /***********************************************************************
 377  *           C16ThkSL01                         (KERNEL.631)
 378  */
 379
 380 void WINAPI C16ThkSL01(CONTEXT86 *context)
 381 {
 382     LPBYTE stub = PTR_SEG_TO_LIN(EAX_reg(context)), x = stub;
 383
 384     if (stub)
 385     {
 386         struct ThunkDataSL16 *SL16 = PTR_SEG_TO_LIN(EDX_reg(context));
 387         struct ThunkDataSL *td = SL16->fpData;
 388
 389         DWORD procAddress = (DWORD)GetProcAddress16(GetModuleHandle16("KERNEL"), 631);
 390         WORD cs = __get_cs();
 391
 392         if (!td)
 393         {
 394             ERR("ThunkConnect16 was not called!\n");
 395             return;
 396         }
 397
 398         TRACE("Creating stub for ThunkDataSL %08lx\n", (DWORD)td);
 399
 400
 401         /* We produce the following code:
 402          *
 403          *   xor eax, eax
 404          *   mov edx, $td
 405          *   call C16ThkSL01
 406          *   push bp
 407          *   push edx
 408          *   push dx
 409          *   push edx
 410          *   call __FLATCS:CallFrom16Thunk
 411          */
 412
 413         *x++ = 0x66; *x++ = 0x33; *x++ = 0xC0;
 414         *x++ = 0x66; *x++ = 0xBA; *((DWORD *)x)++ = (DWORD)td;
 415         *x++ = 0x9A; *((DWORD *)x)++ = procAddress;
 416
 417         *x++ = 0x55;
 418         *x++ = 0x66; *x++ = 0x52;
 419         *x++ = 0x52;
 420         *x++ = 0x66; *x++ = 0x52;
 421         *x++ = 0x66; *x++ = 0x9A; *((DWORD *)x)++ = (DWORD)CallFrom16Thunk;
 422                                   *((WORD *)x)++ = cs;
 423
 424         /* Jump to the stub code just created */
 425         EIP_reg(context) = LOWORD(EAX_reg(context));
 426         CS_reg(context)  = HIWORD(EAX_reg(context));
 427
 428         /* Since C16ThkSL01 got called by a jmp, we need to leave the
 429            orginal return address on the stack */
 430         ESP_reg(context) -= 4;
 431     }
 432     else
 433     {
 434         struct ThunkDataSL *td = (struct ThunkDataSL *)EDX_reg(context);
 435         DWORD targetNr = CX_reg(context) / 4;
 436         struct SLTargetDB *tdb;
 437
 438         TRACE("Process %08lx calling target %ld of ThunkDataSL %08lx\n",
 439               (DWORD)PROCESS_Current(), targetNr, (DWORD)td);
 440
 441         for (tdb = td->targetDB; tdb; tdb = tdb->next)
 442             if (tdb->process == PROCESS_Current())
 443                 break;
 444
 445         if (!tdb)
 446         {
 447             TRACE("Loading 32-bit library %s\n", td->pszDll32);
 448             LoadLibraryA(td->pszDll32);
 449
 450             for (tdb = td->targetDB; tdb; tdb = tdb->next)
 451                 if (tdb->process == PROCESS_Current())
 452                     break;
 453         }
 454
 455         if (tdb)
 456         {
 457             EDX_reg(context) = tdb->targetTable[targetNr];
 458
 459             TRACE("Call target is %08lx\n", EDX_reg(context));
 460         }
 461         else
 462         {
 463             WORD *stack = PTR_SEG_OFF_TO_LIN(SS_reg(context), LOWORD(ESP_reg(context)));
 464             DX_reg(context) = HIWORD(td->apiDB[targetNr].errorReturnValue);
 465             AX_reg(context) = LOWORD(td->apiDB[targetNr].errorReturnValue);
 466             EIP_reg(context) = stack[2];
 467             CS_reg(context)  = stack[3];
 468             ESP_reg(context) += td->apiDB[targetNr].nrArgBytes + 4;
 469
 470             ERR("Process %08lx did not ThunkConnect32 %s to %s\n",
 471                 (DWORD)PROCESS_Current(), td->pszDll32, td->pszDll16);
 472         }
 473     }
 474 }
 475
 476
 477
 478 /***********************************************************************
 479  * 16<->32 Thunklet/Callback API:
 480  */
 481
 482 #include "pshpack1.h"
 483 typedef struct _THUNKLET
 484 {
 485     BYTE        prefix_target;
 486     BYTE        pushl_target;
 487     DWORD       target;
 488
 489     BYTE        prefix_relay;
 490     BYTE        pushl_relay;
 491     DWORD       relay;
 492
 493     BYTE        jmp_glue;
 494     DWORD       glue;
 495
 496     BYTE        type;
 497     HINSTANCE16 owner;
 498     struct _THUNKLET *next;
 499 } THUNKLET;
 500 #include "poppack.h"
 501
 502 #define THUNKLET_TYPE_LS  1
 503 #define THUNKLET_TYPE_SL  2
 504
 505 static HANDLE  ThunkletHeap = 0;
 506 static THUNKLET *ThunkletAnchor = NULL;
 507
 508 static FARPROC ThunkletSysthunkGlueLS = 0;
 509 static SEGPTR    ThunkletSysthunkGlueSL = 0;
 510
 511 static FARPROC ThunkletCallbackGlueLS = 0;
 512 static SEGPTR    ThunkletCallbackGlueSL = 0;
 513
 514 /***********************************************************************
 515  *     THUNK_ThunkletInit
 516  */
 517 static BOOL THUNK_ThunkletInit( void )
 518 {
 519     LPBYTE thunk;
 520
 521     ThunkletHeap = HeapCreate(HEAP_WINE_SEGPTR | HEAP_WINE_CODE16SEG, 0, 0);
 522     if (!ThunkletHeap) return FALSE;
 523
 524     thunk = HeapAlloc( ThunkletHeap, 0, 5 );
 525     if (!thunk) return FALSE;
 526
 527     ThunkletSysthunkGlueLS = (FARPROC)thunk;
 528     *thunk++ = 0x58;                             /* popl eax */
 529     *thunk++ = 0xC3;                             /* ret      */
 530
 531     ThunkletSysthunkGlueSL = HEAP_GetSegptr( ThunkletHeap, 0, thunk );
 532     *thunk++ = 0x66; *thunk++ = 0x58;            /* popl eax */
 533     *thunk++ = 0xCB;                             /* lret     */
 534
 535     return TRUE;
 536 }
 537
 538 /***********************************************************************
 539  *     SetThunkletCallbackGlue             (KERNEL.560)
 540  */
 541 void WINAPI SetThunkletCallbackGlue16( FARPROC glueLS, SEGPTR glueSL )
 542 {
 543     ThunkletCallbackGlueLS = glueLS;
 544     ThunkletCallbackGlueSL = glueSL;
 545 }
 546
 547
 548 /***********************************************************************
 549  *     THUNK_FindThunklet
 550  */
 551 THUNKLET *THUNK_FindThunklet( DWORD target, DWORD relay,
 552                               DWORD glue, BYTE type )
 553 {
 554     THUNKLET *thunk;
 555
 556     for (thunk = ThunkletAnchor; thunk; thunk = thunk->next)
 557         if (    thunk->type   == type
 558              && thunk->target == target
 559              && thunk->relay  == relay
 560              && ( type == THUNKLET_TYPE_LS ?
 561                     ( thunk->glue == glue - (DWORD)&thunk->type )
 562                   : ( thunk->glue == glue ) ) )
 563             return thunk;
 564
 565      return NULL;
 566 }
 567
 568 /***********************************************************************
 569  *     THUNK_AllocLSThunklet
 570  */
 571 FARPROC THUNK_AllocLSThunklet( SEGPTR target, DWORD relay,
 572                                  FARPROC glue, HTASK16 owner )
 573 {
 574     THUNKLET *thunk = THUNK_FindThunklet( (DWORD)target, relay, (DWORD)glue,
 575                                           THUNKLET_TYPE_LS );
 576     if (!thunk)
 577     {
 578         TDB *pTask = (TDB*)GlobalLock16( owner );
 579
 580         if ( !(thunk = HeapAlloc( ThunkletHeap, 0, sizeof(THUNKLET) )) )
 581             return 0;
 582
 583         thunk->prefix_target = thunk->prefix_relay = 0x90;
 584         thunk->pushl_target  = thunk->pushl_relay  = 0x68;
 585         thunk->jmp_glue = 0xE9;
 586
 587         thunk->target  = (DWORD)target;
 588         thunk->relay   = (DWORD)relay;
 589         thunk->glue    = (DWORD)glue - (DWORD)&thunk->type;
 590
 591         thunk->type    = THUNKLET_TYPE_LS;
 592         thunk->owner   = pTask? pTask->hInstance : 0;
 593
 594         thunk->next    = ThunkletAnchor;
 595         ThunkletAnchor = thunk;
 596     }
 597
 598     return (FARPROC)thunk;
 599 }
 600
 601 /***********************************************************************
 602  *     THUNK_AllocSLThunklet
 603  */
 604 SEGPTR THUNK_AllocSLThunklet( FARPROC target, DWORD relay,
 605                               SEGPTR glue, HTASK16 owner )
 606 {
 607     THUNKLET *thunk = THUNK_FindThunklet( (DWORD)target, relay, (DWORD)glue,
 608                                           THUNKLET_TYPE_SL );
 609     if (!thunk)
 610     {
 611         TDB *pTask = (TDB*)GlobalLock16( owner );
 612
 613         if ( !(thunk = HeapAlloc( ThunkletHeap, 0, sizeof(THUNKLET) )) )
 614             return 0;
 615
 616         thunk->prefix_target = thunk->prefix_relay = 0x66;
 617         thunk->pushl_target  = thunk->pushl_relay  = 0x68;
 618         thunk->jmp_glue = 0xEA;
 619
 620         thunk->target  = (DWORD)target;
 621         thunk->relay   = (DWORD)relay;
 622         thunk->glue    = (DWORD)glue;
 623
 624         thunk->type    = THUNKLET_TYPE_SL;
 625         thunk->owner   = pTask? pTask->hInstance : 0;
 626
 627         thunk->next    = ThunkletAnchor;
 628         ThunkletAnchor = thunk;
 629     }
 630
 631     return HEAP_GetSegptr( ThunkletHeap, 0, thunk );
 632 }
 633
 634 /**********************************************************************
 635  *     IsLSThunklet
 636  */
 637 BOOL16 WINAPI IsLSThunklet( THUNKLET *thunk )
 638 {
 639     return    thunk->prefix_target == 0x90 && thunk->pushl_target == 0x68
 640            && thunk->prefix_relay  == 0x90 && thunk->pushl_relay  == 0x68
 641            && thunk->jmp_glue == 0xE9 && thunk->type == THUNKLET_TYPE_LS;
 642 }
 643
 644 /**********************************************************************
 645  *     IsSLThunklet                        (KERNEL.612)
 646  */
 647 BOOL16 WINAPI IsSLThunklet16( THUNKLET *thunk )
 648 {
 649     return    thunk->prefix_target == 0x66 && thunk->pushl_target == 0x68
 650            && thunk->prefix_relay  == 0x66 && thunk->pushl_relay  == 0x68
 651            && thunk->jmp_glue == 0xEA && thunk->type == THUNKLET_TYPE_SL;
 652 }
 653
 654
 655
 656 /***********************************************************************
 657  *     AllocLSThunkletSysthunk             (KERNEL.607)
 658  */
 659 FARPROC WINAPI AllocLSThunkletSysthunk16( SEGPTR target,
 660                                           FARPROC relay, DWORD dummy )
 661 {
 662     return THUNK_AllocLSThunklet( (SEGPTR)relay, (DWORD)target,
 663                                   ThunkletSysthunkGlueLS, GetCurrentTask() );
 664 }
 665
 666 /***********************************************************************
 667  *     AllocSLThunkletSysthunk             (KERNEL.608)
 668  */
 669 SEGPTR WINAPI AllocSLThunkletSysthunk16( FARPROC target,
 670                                        SEGPTR relay, DWORD dummy )
 671 {
 672     return THUNK_AllocSLThunklet( (FARPROC)relay, (DWORD)target,
 673                                   ThunkletSysthunkGlueSL, GetCurrentTask() );
 674 }
 675
 676
 677 /***********************************************************************
 678  *     AllocLSThunkletCallbackEx           (KERNEL.567)
 679  */
 680 FARPROC WINAPI AllocLSThunkletCallbackEx16( SEGPTR target,
 681                                             DWORD relay, HTASK16 task )
 682 {
 683     THUNKLET *thunk = (THUNKLET *)PTR_SEG_TO_LIN( target );
 684     if ( !thunk ) return NULL;
 685
 686     if (   IsSLThunklet16( thunk ) && thunk->relay == relay
 687         && thunk->glue == (DWORD)ThunkletCallbackGlueSL )
 688         return (FARPROC)thunk->target;
 689
 690     return THUNK_AllocLSThunklet( target, relay,
 691                                   ThunkletCallbackGlueLS, task );
 692 }
 693
 694 /***********************************************************************
 695  *     AllocSLThunkletCallbackEx           (KERNEL.568)
 696  */
 697 SEGPTR WINAPI AllocSLThunkletCallbackEx16( FARPROC target,
 698                                          DWORD relay, HTASK16 task )
 699 {
 700     THUNKLET *thunk = (THUNKLET *)target;
 701     if ( !thunk ) return 0;
 702
 703     if (   IsLSThunklet( thunk ) && thunk->relay == relay
 704         && thunk->glue == (DWORD)ThunkletCallbackGlueLS - (DWORD)&thunk->type )
 705         return (SEGPTR)thunk->target;
 706
 707     return THUNK_AllocSLThunklet( target, relay,
 708                                   ThunkletCallbackGlueSL, task );
 709 }
 710
 711 /***********************************************************************
 712  *     AllocLSThunkletCallback             (KERNEL.561) (KERNEL.606)
 713  */
 714 FARPROC WINAPI AllocLSThunkletCallback16( SEGPTR target, DWORD relay )
 715 {
 716     return AllocLSThunkletCallbackEx16( target, relay, GetCurrentTask() );
 717 }
 718
 719 /***********************************************************************
 720  *     AllocSLThunkletCallback             (KERNEL.562) (KERNEL.605)
 721  */
 722 SEGPTR WINAPI AllocSLThunkletCallback16( FARPROC target, DWORD relay )
 723 {
 724     return AllocSLThunkletCallbackEx16( target, relay, GetCurrentTask() );
 725 }
 726
 727 /***********************************************************************
 728  *     FindLSThunkletCallback              (KERNEL.563) (KERNEL.609)
 729  */
 730 FARPROC WINAPI FindLSThunkletCallback( SEGPTR target, DWORD relay )
 731 {
 732     THUNKLET *thunk = (THUNKLET *)PTR_SEG_TO_LIN( target );
 733     if (   thunk && IsSLThunklet16( thunk ) && thunk->relay == relay
 734         && thunk->glue == (DWORD)ThunkletCallbackGlueSL )
 735         return (FARPROC)thunk->target;
 736
 737     thunk = THUNK_FindThunklet( (DWORD)target, relay,
 738                                 (DWORD)ThunkletCallbackGlueLS,
 739                                 THUNKLET_TYPE_LS );
 740     return (FARPROC)thunk;
 741 }
 742
 743 /***********************************************************************
 744  *     FindSLThunkletCallback              (KERNEL.564) (KERNEL.610)
 745  */
 746 SEGPTR WINAPI FindSLThunkletCallback( FARPROC target, DWORD relay )
 747 {
 748     THUNKLET *thunk = (THUNKLET *)target;
 749     if (   thunk && IsLSThunklet( thunk ) && thunk->relay == relay
 750         && thunk->glue == (DWORD)ThunkletCallbackGlueLS - (DWORD)&thunk->type )
 751         return (SEGPTR)thunk->target;
 752
 753     thunk = THUNK_FindThunklet( (DWORD)target, relay,
 754                                 (DWORD)ThunkletCallbackGlueSL,
 755                                 THUNKLET_TYPE_SL );
 756     return HEAP_GetSegptr( ThunkletHeap, 0, thunk );
 757 }
 758
 759
 760 /***********************************************************************
 761  *     FreeThunklet16            (KERNEL.611)
 762  */
 763 BOOL16 WINAPI FreeThunklet16( DWORD unused1, DWORD unused2 )
 764 {
 765     return FALSE;
 766 }
 767
 768 /***********************************************************************
 769  * Callback Client API
 770  */
 771
 772 #define N_CBC_FIXED    20
 773 #define N_CBC_VARIABLE 10
 774 #define N_CBC_TOTAL    (N_CBC_FIXED + N_CBC_VARIABLE)
 775
 776 static SEGPTR CBClientRelay16[ N_CBC_TOTAL ];
 777 static FARPROC *CBClientRelay32[ N_CBC_TOTAL ];
 778
 779 /***********************************************************************
 780  *     RegisterCBClient                    (KERNEL.619)
 781  */
 782 INT16 WINAPI RegisterCBClient16( INT16 wCBCId,
 783                                  SEGPTR relay16, FARPROC *relay32 )
 784 {
 785     /* Search for free Callback ID */
 786     if ( wCBCId == -1 )
 787         for ( wCBCId = N_CBC_FIXED; wCBCId < N_CBC_TOTAL; wCBCId++ )
 788             if ( !CBClientRelay16[ wCBCId ] )
 789                 break;
 790
 791     /* Register Callback ID */
 792     if ( wCBCId > 0 && wCBCId < N_CBC_TOTAL )
 793     {
 794         CBClientRelay16[ wCBCId ] = relay16;
 795         CBClientRelay32[ wCBCId ] = relay32;
 796     }
 797     else
 798         wCBCId = 0;
 799
 800     return wCBCId;
 801 }
 802
 803 /***********************************************************************
 804  *     UnRegisterCBClient                  (KERNEL.622)
 805  */
 806 INT16 WINAPI UnRegisterCBClient16( INT16 wCBCId,
 807                                    SEGPTR relay16, FARPROC *relay32 )
 808 {
 809     if (    wCBCId >= N_CBC_FIXED && wCBCId < N_CBC_TOTAL
 810          && CBClientRelay16[ wCBCId ] == relay16
 811          && CBClientRelay32[ wCBCId ] == relay32 )
 812     {
 813         CBClientRelay16[ wCBCId ] = 0;
 814         CBClientRelay32[ wCBCId ] = 0;
 815     }
 816     else
 817         wCBCId = 0;
 818
 819     return wCBCId;
 820 }
 821
 822
 823 /***********************************************************************
 824  *     InitCBClient                        (KERNEL.623)
 825  */
 826 void WINAPI InitCBClient16( FARPROC glueLS )
 827 {
 828     HMODULE16 kernel = GetModuleHandle16( "KERNEL" );
 829     SEGPTR glueSL = (SEGPTR)WIN32_GetProcAddress16( kernel, (LPCSTR)604 );
 830
 831     SetThunkletCallbackGlue16( glueLS, glueSL );
 832 }
 833
 834 /***********************************************************************
 835  *     CBClientGlueSL                      (KERNEL.604)
 836  */
 837 void WINAPI CBClientGlueSL( CONTEXT86 *context )
 838 {
 839     /* Create stack frame */
 840     SEGPTR stackSeg = stack16_push( 12 );
 841     LPWORD stackLin = PTR_SEG_TO_LIN( stackSeg );
 842     SEGPTR glue, *glueTab;
 843
 844     stackLin[3] = BP_reg( context );
 845     stackLin[2] = SI_reg( context );
 846     stackLin[1] = DI_reg( context );
 847     stackLin[0] = DS_reg( context );
 848
 849     EBP_reg( context ) = OFFSETOF( stackSeg ) + 6;
 850     ESP_reg( context ) = OFFSETOF( stackSeg ) - 4;
 851     GS_reg( context ) = 0;
 852
 853     /* Jump to 16-bit relay code */
 854     glueTab = PTR_SEG_TO_LIN( CBClientRelay16[ stackLin[5] ] );
 855     glue = glueTab[ stackLin[4] ];
 856     CS_reg ( context ) = SELECTOROF( glue );
 857     EIP_reg( context ) = OFFSETOF  ( glue );
 858 }
 859
 860 /***********************************************************************
 861  *     CBClientThunkSL                      (KERNEL.620)
 862  */
 863 extern DWORD CALL32_CBClient( FARPROC proc, LPWORD args, DWORD *esi );
 864 void WINAPI CBClientThunkSL( CONTEXT86 *context )
 865 {
 866     /* Call 32-bit relay code */
 867
 868     LPWORD args = PTR_SEG_OFF_TO_LIN( SS_reg( context ), BP_reg( context ) );
 869     FARPROC proc = CBClientRelay32[ args[2] ][ args[1] ];
 870
 871     EAX_reg(context) = CALL32_CBClient( proc, args, &ESI_reg( context ) );
 872 }
 873
 874 /***********************************************************************
 875  *     CBClientThunkSLEx                    (KERNEL.621)
 876  */
 877 extern DWORD CALL32_CBClientEx( FARPROC proc, LPWORD args, DWORD *esi, INT *nArgs );
 878 void WINAPI CBClientThunkSLEx( CONTEXT86 *context )
 879 {
 880     /* Call 32-bit relay code */
 881
 882     LPWORD args = PTR_SEG_OFF_TO_LIN( SS_reg( context ), BP_reg( context ) );
 883     FARPROC proc = CBClientRelay32[ args[2] ][ args[1] ];
 884     INT nArgs;
 885     LPWORD stackLin;
 886
 887     EAX_reg(context) = CALL32_CBClientEx( proc, args, &ESI_reg( context ), &nArgs );
 888
 889     /* Restore registers saved by CBClientGlueSL */
 890     stackLin = (LPWORD)((LPBYTE)CURRENT_STACK16 + sizeof(STACK16FRAME) - 4);
 891     BP_reg( context ) = stackLin[3];
 892     SI_reg( context ) = stackLin[2];
 893     DI_reg( context ) = stackLin[1];
 894     DS_reg( context ) = stackLin[0];
 895     ESP_reg( context ) += 16+nArgs;
 896
 897     /* Return to caller of CBClient thunklet */
 898     CS_reg ( context ) = stackLin[9];
 899     EIP_reg( context ) = stackLin[8];
 900 }
 901