dlls/jscript/jsutils.c

   1 /*
   2  * Copyright 2008 Jacek Caban for CodeWeavers
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2.1 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with this library; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  17  */
  18
  19 #include "config.h"
  20 #include "wine/port.h"
  21
  22 #include <math.h>
  23 #include <assert.h>
  24
  25 #include "jscript.h"
  26 #include "engine.h"
  27
  28 #include "wine/debug.h"
  29
  30 WINE_DEFAULT_DEBUG_CHANNEL(jscript);
  31 WINE_DECLARE_DEBUG_CHANNEL(heap);
  32
  33 const char *debugstr_variant(const VARIANT *v)
  34 {
  35     if(!v)
  36         return "(null)";
  37
  38     switch(V_VT(v)) {
  39     case VT_EMPTY:
  40         return "{VT_EMPTY}";
  41     case VT_NULL:
  42         return "{VT_NULL}";
  43     case VT_I4:
  44         return wine_dbg_sprintf("{VT_I4: %d}", V_I4(v));
  45     case VT_UI4:
  46         return wine_dbg_sprintf("{VT_UI4: %u}", V_UI4(v));
  47     case VT_R8:
  48         return wine_dbg_sprintf("{VT_R8: %lf}", V_R8(v));
  49     case VT_BSTR:
  50         return wine_dbg_sprintf("{VT_BSTR: %s}", debugstr_w(V_BSTR(v)));
  51     case VT_DISPATCH:
  52         return wine_dbg_sprintf("{VT_DISPATCH: %p}", V_DISPATCH(v));
  53     case VT_BOOL:
  54         return wine_dbg_sprintf("{VT_BOOL: %x}", V_BOOL(v));
  55     default:
  56         return wine_dbg_sprintf("{vt %d}", V_VT(v));
  57     }
  58 }
  59
  60 #define MIN_BLOCK_SIZE  128
  61 #define ARENA_FREE_FILLER  0xaa
  62
  63 static inline DWORD block_size(DWORD block)
  64 {
  65     return MIN_BLOCK_SIZE << block;
  66 }
  67
  68 void jsheap_init(jsheap_t *heap)
  69 {
  70     memset(heap, 0, sizeof(*heap));
  71     list_init(&heap->custom_blocks);
  72 }
  73
  74 void *jsheap_alloc(jsheap_t *heap, DWORD size)
  75 {
  76     struct list *list;
  77     void *tmp;
  78
  79     if(!heap->block_cnt) {
  80         if(!heap->blocks) {
  81             heap->blocks = heap_alloc(sizeof(void*));
  82             if(!heap->blocks)
  83                 return NULL;
  84         }
  85
  86         tmp = heap_alloc(block_size(0));
  87         if(!tmp)
  88             return NULL;
  89
  90         heap->blocks[0] = tmp;
  91         heap->block_cnt = 1;
  92     }
  93
  94     if(heap->offset + size <= block_size(heap->last_block)) {
  95         tmp = ((BYTE*)heap->blocks[heap->last_block])+heap->offset;
  96         heap->offset += size;
  97         return tmp;
  98     }
  99
 100     if(size <= block_size(heap->last_block+1)) {
 101         if(heap->last_block+1 == heap->block_cnt) {
 102             tmp = heap_realloc(heap->blocks, (heap->block_cnt+1)*sizeof(void*));
 103             if(!tmp)
 104                 return NULL;
 105
 106             heap->blocks = tmp;
 107             heap->blocks[heap->block_cnt] = heap_alloc(block_size(heap->block_cnt));
 108             if(!heap->blocks[heap->block_cnt])
 109                 return NULL;
 110
 111             heap->block_cnt++;
 112         }
 113
 114         heap->last_block++;
 115         heap->offset = size;
 116         return heap->blocks[heap->last_block];
 117     }
 118
 119     list = heap_alloc(size + sizeof(struct list));
 120     if(!list)
 121         return NULL;
 122
 123     list_add_head(&heap->custom_blocks, list);
 124     return list+1;
 125 }
 126
 127 void *jsheap_grow(jsheap_t *heap, void *mem, DWORD size, DWORD inc)
 128 {
 129     if(mem == (BYTE*)heap->blocks[heap->last_block] + heap->offset-size
 130        && heap->offset+inc < block_size(heap->last_block)) {
 131         heap->offset += inc;
 132         return mem;
 133     }
 134
 135     return jsheap_alloc(heap, size+inc);
 136 }
 137
 138 void jsheap_clear(jsheap_t *heap)
 139 {
 140     struct list *tmp;
 141
 142     if(!heap)
 143         return;
 144
 145     while((tmp = list_next(&heap->custom_blocks, &heap->custom_blocks))) {
 146         list_remove(tmp);
 147         heap_free(tmp);
 148     }
 149
 150     if(WARN_ON(heap)) {
 151         DWORD i;
 152
 153         for(i=0; i < heap->block_cnt; i++)
 154             memset(heap->blocks[i], ARENA_FREE_FILLER, block_size(i));
 155     }
 156
 157     heap->last_block = heap->offset = 0;
 158     heap->mark = FALSE;
 159 }
 160
 161 void jsheap_free(jsheap_t *heap)
 162 {
 163     DWORD i;
 164
 165     jsheap_clear(heap);
 166
 167     for(i=0; i < heap->block_cnt; i++)
 168         heap_free(heap->blocks[i]);
 169     heap_free(heap->blocks);
 170
 171     jsheap_init(heap);
 172 }
 173
 174 jsheap_t *jsheap_mark(jsheap_t *heap)
 175 {
 176     if(heap->mark)
 177         return NULL;
 178
 179     heap->mark = TRUE;
 180     return heap;
 181 }
 182
 183 /* ECMA-262 3rd Edition    9.1 */
 184 HRESULT to_primitive(script_ctx_t *ctx, VARIANT *v, jsexcept_t *ei, VARIANT *ret, hint_t hint)
 185 {
 186     switch(V_VT(v)) {
 187     case VT_EMPTY:
 188     case VT_NULL:
 189     case VT_BOOL:
 190     case VT_I4:
 191     case VT_R8:
 192         *ret = *v;
 193         break;
 194     case VT_BSTR:
 195         V_VT(ret) = VT_BSTR;
 196         V_BSTR(ret) = SysAllocString(V_BSTR(v));
 197         break;
 198     case VT_DISPATCH: {
 199         jsdisp_t *jsdisp;
 200         DISPID id;
 201         DISPPARAMS dp = {NULL, NULL, 0, 0};
 202         HRESULT hres;
 203
 204         static const WCHAR toStringW[] = {'t','o','S','t','r','i','n','g',0};
 205         static const WCHAR valueOfW[] = {'v','a','l','u','e','O','f',0};
 206
 207         if(!V_DISPATCH(v)) {
 208             V_VT(ret) = VT_NULL;
 209             break;
 210         }
 211
 212         jsdisp = iface_to_jsdisp((IUnknown*)V_DISPATCH(v));
 213         if(!jsdisp) {
 214             V_VT(ret) = VT_EMPTY;
 215             return disp_propget(ctx, V_DISPATCH(v), DISPID_VALUE, ret, ei);
 216         }
 217
 218         if(hint == NO_HINT)
 219             hint = is_class(jsdisp, JSCLASS_DATE) ? HINT_STRING : HINT_NUMBER;
 220
 221         /* Native implementation doesn't throw TypeErrors, returns strange values */
 222
 223         hres = jsdisp_get_id(jsdisp, hint == HINT_STRING ? toStringW : valueOfW, 0, &id);
 224         if(SUCCEEDED(hres)) {
 225             hres = jsdisp_call(jsdisp, id, DISPATCH_METHOD, &dp, ret, ei);
 226             if(FAILED(hres)) {
 227                 WARN("call error - forwarding exception\n");
 228                 jsdisp_release(jsdisp);
 229                 return hres;
 230             }
 231             else if(V_VT(ret) != VT_DISPATCH) {
 232                 jsdisp_release(jsdisp);
 233                 return S_OK;
 234             }
 235             else
 236                 IDispatch_Release(V_DISPATCH(ret));
 237         }
 238
 239         hres = jsdisp_get_id(jsdisp, hint == HINT_STRING ? valueOfW : toStringW, 0, &id);
 240         if(SUCCEEDED(hres)) {
 241             hres = jsdisp_call(jsdisp, id, DISPATCH_METHOD, &dp, ret, ei);
 242             if(FAILED(hres)) {
 243                 WARN("call error - forwarding exception\n");
 244                 jsdisp_release(jsdisp);
 245                 return hres;
 246             }
 247             else if(V_VT(ret) != VT_DISPATCH) {
 248                 jsdisp_release(jsdisp);
 249                 return S_OK;
 250             }
 251             else
 252                 IDispatch_Release(V_DISPATCH(ret));
 253         }
 254
 255         jsdisp_release(jsdisp);
 256
 257         WARN("failed\n");
 258         return throw_type_error(ctx, ei, JS_E_TO_PRIMITIVE, NULL);
 259     }
 260     default:
 261         FIXME("Unimplemented for vt %d\n", V_VT(v));
 262         return E_NOTIMPL;
 263     }
 264
 265     return S_OK;
 266 }
 267
 268 /* ECMA-262 3rd Edition    9.2 */
 269 HRESULT to_boolean(VARIANT *v, VARIANT_BOOL *b)
 270 {
 271     switch(V_VT(v)) {
 272     case VT_EMPTY:
 273     case VT_NULL:
 274         *b = VARIANT_FALSE;
 275         break;
 276     case VT_I4:
 277         *b = V_I4(v) ? VARIANT_TRUE : VARIANT_FALSE;
 278         break;
 279     case VT_R8:
 280         if(isnan(V_R8(v))) *b = VARIANT_FALSE;
 281         else *b = V_R8(v) ? VARIANT_TRUE : VARIANT_FALSE;
 282         break;
 283     case VT_BSTR:
 284         *b = V_BSTR(v) && *V_BSTR(v) ? VARIANT_TRUE : VARIANT_FALSE;
 285         break;
 286     case VT_DISPATCH:
 287         *b = V_DISPATCH(v) ? VARIANT_TRUE : VARIANT_FALSE;
 288         break;
 289     case VT_BOOL:
 290         *b = V_BOOL(v);
 291         break;
 292     default:
 293         FIXME("unimplemented for vt %d\n", V_VT(v));
 294         return E_NOTIMPL;
 295     }
 296
 297     return S_OK;
 298 }
 299
 300 static int hex_to_int(WCHAR c)
 301 {
 302     if('0' <= c && c <= '9')
 303         return c-'0';
 304
 305     if('a' <= c && c <= 'f')
 306         return c-'a'+10;
 307
 308     if('A' <= c && c <= 'F')
 309         return c-'A'+10;
 310
 311     return -1;
 312 }
 313
 314 /* ECMA-262 3rd Edition    9.3.1 */
 315 static HRESULT str_to_number(BSTR str, double *ret)
 316 {
 317     const WCHAR *ptr = str;
 318     BOOL neg = FALSE;
 319     DOUBLE d = 0.0;
 320
 321     static const WCHAR infinityW[] = {'I','n','f','i','n','i','t','y'};
 322
 323     if(!ptr) {
 324         *ret = 0;
 325         return S_OK;
 326     }
 327
 328     while(isspaceW(*ptr))
 329         ptr++;
 330
 331     if(*ptr == '-') {
 332         neg = TRUE;
 333         ptr++;
 334     }else if(*ptr == '+') {
 335         ptr++;
 336     }
 337
 338     if(!strncmpW(ptr, infinityW, sizeof(infinityW)/sizeof(WCHAR))) {
 339         ptr += sizeof(infinityW)/sizeof(WCHAR);
 340         while(*ptr && isspaceW(*ptr))
 341             ptr++;
 342
 343         if(*ptr)
 344             *ret = ret_nan();
 345         else
 346             *ret = neg ? -ret_inf() : ret_inf();
 347         return S_OK;
 348     }
 349
 350     if(*ptr == '0' && ptr[1] == 'x') {
 351         DWORD l = 0;
 352
 353         ptr += 2;
 354         while((l = hex_to_int(*ptr)) != -1) {
 355             d = d*16 + l;
 356             ptr++;
 357         }
 358
 359         *ret = d;
 360         return S_OK;
 361     }
 362
 363     while(isdigitW(*ptr))
 364         d = d*10 + (*ptr++ - '0');
 365
 366     if(*ptr == 'e' || *ptr == 'E') {
 367         BOOL eneg = FALSE;
 368         LONG l = 0;
 369
 370         ptr++;
 371         if(*ptr == '-') {
 372             ptr++;
 373             eneg = TRUE;
 374         }else if(*ptr == '+') {
 375             ptr++;
 376         }
 377
 378         while(isdigitW(*ptr))
 379             l = l*10 + (*ptr++ - '0');
 380         if(eneg)
 381             l = -l;
 382
 383         d *= pow(10, l);
 384     }else if(*ptr == '.') {
 385         DOUBLE dec = 0.1;
 386
 387         ptr++;
 388         while(isdigitW(*ptr)) {
 389             d += dec * (*ptr++ - '0');
 390             dec *= 0.1;
 391         }
 392     }
 393
 394     while(isspaceW(*ptr))
 395         ptr++;
 396
 397     if(*ptr) {
 398         *ret = ret_nan();
 399         return S_OK;
 400     }
 401
 402     if(neg)
 403         d = -d;
 404
 405     *ret = d;
 406     return S_OK;
 407 }
 408
 409 /* ECMA-262 3rd Edition    9.3 */
 410 HRESULT to_number(script_ctx_t *ctx, VARIANT *v, jsexcept_t *ei, double *ret)
 411 {
 412     switch(V_VT(v)) {
 413     case VT_EMPTY:
 414         *ret = ret_nan();
 415         break;
 416     case VT_NULL:
 417         *ret = 0;
 418         break;
 419     case VT_I4:
 420         *ret = V_I4(v);
 421         break;
 422     case VT_R8:
 423         *ret = V_R8(v);
 424         break;
 425     case VT_BSTR:
 426         return str_to_number(V_BSTR(v), ret);
 427     case VT_DISPATCH: {
 428         VARIANT prim;
 429         HRESULT hres;
 430
 431         hres = to_primitive(ctx, v, ei, &prim, HINT_NUMBER);
 432         if(FAILED(hres))
 433             return hres;
 434
 435         hres = to_number(ctx, &prim, ei, ret);
 436         VariantClear(&prim);
 437         return hres;
 438     }
 439     case VT_BOOL:
 440         *ret = V_BOOL(v) ? 1 : 0;
 441         break;
 442     default:
 443         FIXME("unimplemented for vt %d\n", V_VT(v));
 444         return E_NOTIMPL;
 445     }
 446
 447     return S_OK;
 448 }
 449
 450 /* ECMA-262 3rd Edition    9.4 */
 451 HRESULT to_integer(script_ctx_t *ctx, VARIANT *v, jsexcept_t *ei, VARIANT *ret)
 452 {
 453     double n;
 454     HRESULT hres;
 455
 456     if(V_VT(v) == VT_I4) {
 457         *ret = *v;
 458         return S_OK;
 459     }
 460
 461     hres = to_number(ctx, v, ei, &n);
 462     if(FAILED(hres))
 463         return hres;
 464
 465     if(isnan(n)) {
 466         V_VT(ret) = VT_I4;
 467         V_I4(ret) = 0;
 468     }else {
 469         num_set_val(ret, n >= 0.0 ? floor(n) : -floor(-n));
 470     }
 471
 472     return S_OK;
 473 }
 474
 475 /* ECMA-262 3rd Edition    9.5 */
 476 HRESULT to_int32(script_ctx_t *ctx, VARIANT *v, jsexcept_t *ei, INT *ret)
 477 {
 478     double n;
 479     HRESULT hres;
 480
 481     if(V_VT(v) == VT_I4) {
 482         *ret = V_I4(v);
 483         return S_OK;
 484     }
 485
 486     hres = to_number(ctx, v, ei, &n);
 487     if(FAILED(hres))
 488         return hres;
 489
 490     *ret = isnan(n) || isinf(n) ? 0 : n;
 491     return S_OK;
 492 }
 493
 494 /* ECMA-262 3rd Edition    9.6 */
 495 HRESULT to_uint32(script_ctx_t *ctx, VARIANT *v, jsexcept_t *ei, DWORD *ret)
 496 {
 497     double n;
 498     HRESULT hres;
 499
 500     if(V_VT(v) == VT_I4) {
 501         *ret = V_I4(v);
 502         return S_OK;
 503     }
 504
 505     hres = to_number(ctx, v, ei, &n);
 506     if(FAILED(hres))
 507         return hres;
 508
 509     *ret = isnan(n) || isinf(n) ? 0 : n;
 510     return S_OK;
 511 }
 512
 513 BSTR int_to_bstr(int i)
 514 {
 515     WCHAR buf[12], *p;
 516     BOOL neg = FALSE;
 517
 518     if(!i) {
 519         static const WCHAR zeroW[] = {'0',0};
 520         return SysAllocString(zeroW);
 521     }
 522
 523     if(i < 0) {
 524         neg = TRUE;
 525         i = -i;
 526     }
 527
 528     p = buf + sizeof(buf)/sizeof(*buf)-1;
 529     *p-- = 0;
 530     while(i) {
 531         *p-- = i%10 + '0';
 532         i /= 10;
 533     }
 534
 535     if(neg)
 536         *p = '-';
 537     else
 538         p++;
 539
 540     return SysAllocString(p);
 541 }
 542
 543 HRESULT double_to_bstr(double n, BSTR *str)
 544 {
 545     const WCHAR NaNW[] = {'N','a','N',0};
 546     const WCHAR InfinityW[] = {'-','I','n','f','i','n','i','t','y',0};
 547
 548     if(isnan(n)) {
 549        *str = SysAllocString(NaNW);
 550     }else if(isinf(n)) {
 551         *str = SysAllocString(n<0 ? InfinityW : InfinityW+1);
 552     }else {
 553         VARIANT strv, v;
 554         HRESULT hres;
 555
 556         V_VT(&v) = VT_R8;
 557         V_R8(&v) = n;
 558         V_VT(&strv) = VT_EMPTY;
 559         hres = VariantChangeTypeEx(&strv, &v, MAKELCID(MAKELANGID(LANG_ENGLISH,SUBLANG_ENGLISH_US),SORT_DEFAULT), 0, VT_BSTR);
 560         if(FAILED(hres))
 561             return hres;
 562
 563         *str = V_BSTR(&strv);
 564     }
 565
 566     return *str ? S_OK : E_OUTOFMEMORY;
 567 }
 568
 569 /* ECMA-262 3rd Edition    9.8 */
 570 HRESULT to_string(script_ctx_t *ctx, VARIANT *v, jsexcept_t *ei, BSTR *str)
 571 {
 572     const WCHAR undefinedW[] = {'u','n','d','e','f','i','n','e','d',0};
 573     const WCHAR nullW[] = {'n','u','l','l',0};
 574     const WCHAR trueW[] = {'t','r','u','e',0};
 575     const WCHAR falseW[] = {'f','a','l','s','e',0};
 576
 577     switch(V_VT(v)) {
 578     case VT_EMPTY:
 579         *str = SysAllocString(undefinedW);
 580         break;
 581     case VT_NULL:
 582         *str = SysAllocString(nullW);
 583         break;
 584     case VT_I4:
 585         *str = int_to_bstr(V_I4(v));
 586         break;
 587     case VT_R8:
 588         return double_to_bstr(V_R8(v), str);
 589     case VT_BSTR:
 590         *str = SysAllocString(V_BSTR(v));
 591         break;
 592     case VT_DISPATCH: {
 593         VARIANT prim;
 594         HRESULT hres;
 595
 596         hres = to_primitive(ctx, v, ei, &prim, HINT_STRING);
 597         if(FAILED(hres))
 598             return hres;
 599
 600         hres = to_string(ctx, &prim, ei, str);
 601         VariantClear(&prim);
 602         return hres;
 603     }
 604     case VT_BOOL:
 605         *str = SysAllocString(V_BOOL(v) ? trueW : falseW);
 606         break;
 607     default:
 608         FIXME("unsupported vt %d\n", V_VT(v));
 609         return E_NOTIMPL;
 610     }
 611
 612     return *str ? S_OK : E_OUTOFMEMORY;
 613 }
 614
 615 /* ECMA-262 3rd Edition    9.9 */
 616 HRESULT to_object(script_ctx_t *ctx, VARIANT *v, IDispatch **disp)
 617 {
 618     jsdisp_t *dispex;
 619     HRESULT hres;
 620
 621     switch(V_VT(v)) {
 622     case VT_BSTR:
 623         hres = create_string(ctx, V_BSTR(v), SysStringLen(V_BSTR(v)), &dispex);
 624         if(FAILED(hres))
 625             return hres;
 626
 627         *disp = to_disp(dispex);
 628         break;
 629     case VT_I4:
 630     case VT_R8:
 631         hres = create_number(ctx, num_val(v), &dispex);
 632         if(FAILED(hres))
 633             return hres;
 634
 635         *disp = to_disp(dispex);
 636         break;
 637     case VT_DISPATCH:
 638         if(V_DISPATCH(v)) {
 639             IDispatch_AddRef(V_DISPATCH(v));
 640             *disp = V_DISPATCH(v);
 641         }else {
 642             jsdisp_t *obj;
 643
 644             hres = create_object(ctx, NULL, &obj);
 645             if(FAILED(hres))
 646                 return hres;
 647
 648             *disp = to_disp(obj);
 649         }
 650         break;
 651     case VT_BOOL:
 652         hres = create_bool(ctx, V_BOOL(v), &dispex);
 653         if(FAILED(hres))
 654             return hres;
 655
 656         *disp = to_disp(dispex);
 657         break;
 658     case VT_ARRAY|VT_VARIANT:
 659         hres = create_vbarray(ctx, V_ARRAY(v), &dispex);
 660         if(FAILED(hres))
 661             return hres;
 662
 663         *disp = to_disp(dispex);
 664         break;
 665     default:
 666         FIXME("unsupported vt %d\n", V_VT(v));
 667         return E_NOTIMPL;
 668     }
 669
 670     return S_OK;
 671 }
 672
 673 HRESULT variant_change_type(script_ctx_t *ctx, VARIANT *dst, VARIANT *src, VARTYPE vt)
 674 {
 675     jsexcept_t ei;
 676     HRESULT hres;
 677
 678     memset(&ei, 0, sizeof(ei));
 679
 680     switch(vt) {
 681     case VT_I2:
 682     case VT_I4: {
 683         INT i;
 684
 685         hres = to_int32(ctx, src, &ei, &i);
 686         if(SUCCEEDED(hres)) {
 687             if(vt == VT_I4)
 688                 V_I4(dst) = i;
 689             else
 690                 V_I2(dst) = i;
 691         }
 692         break;
 693     }
 694     case VT_R8: {
 695         double n;
 696         hres = to_number(ctx, src, &ei, &n);
 697         if(SUCCEEDED(hres))
 698             V_R8(dst) = n;
 699         break;
 700     }
 701     case VT_R4: {
 702         double n;
 703
 704         hres = to_number(ctx, src, &ei, &n);
 705         if(SUCCEEDED(hres))
 706             V_R4(dst) = n;
 707         break;
 708     }
 709     case VT_BOOL: {
 710         VARIANT_BOOL b;
 711
 712         hres = to_boolean(src, &b);
 713         if(SUCCEEDED(hres))
 714             V_BOOL(dst) = b;
 715         break;
 716     }
 717     case VT_BSTR: {
 718         BSTR str;
 719
 720         hres = to_string(ctx, src, &ei, &str);
 721         if(SUCCEEDED(hres))
 722             V_BSTR(dst) = str;
 723         break;
 724     }
 725     case VT_EMPTY:
 726         hres = V_VT(src) == VT_EMPTY ? S_OK : E_NOTIMPL;
 727         break;
 728     case VT_NULL:
 729         hres = V_VT(src) == VT_NULL ? S_OK : E_NOTIMPL;
 730         break;
 731     default:
 732         FIXME("vt %d not implemented\n", vt);
 733         hres = E_NOTIMPL;
 734     }
 735
 736     if(FAILED(hres)) {
 737         VariantClear(&ei.var);
 738         return hres;
 739     }
 740
 741     V_VT(dst) = vt;
 742     return S_OK;
 743 }
 744
 745 static inline JSCaller *impl_from_IServiceProvider(IServiceProvider *iface)
 746 {
 747     return CONTAINING_RECORD(iface, JSCaller, IServiceProvider_iface);
 748 }
 749
 750 static HRESULT WINAPI JSCaller_QueryInterface(IServiceProvider *iface, REFIID riid, void **ppv)
 751 {
 752     JSCaller *This = impl_from_IServiceProvider(iface);
 753
 754     if(IsEqualGUID(&IID_IUnknown, riid)) {
 755         TRACE("(%p)->(IID_IUnknown %p)\n", This, ppv);
 756         *ppv = &This->IServiceProvider_iface;
 757     }else if(IsEqualGUID(&IID_IServiceProvider, riid)) {
 758         TRACE("(%p)->(IID_IServiceProvider %p)\n", This, ppv);
 759         *ppv = &This->IServiceProvider_iface;
 760     }else {
 761         WARN("(%p)->(%s %p)\n", This, debugstr_guid(riid), ppv);
 762         *ppv = NULL;
 763         return E_NOINTERFACE;
 764     }
 765
 766     IUnknown_AddRef((IUnknown*)*ppv);
 767     return S_OK;
 768 }
 769
 770 static ULONG WINAPI JSCaller_AddRef(IServiceProvider *iface)
 771 {
 772     JSCaller *This = impl_from_IServiceProvider(iface);
 773     LONG ref = InterlockedIncrement(&This->ref);
 774
 775     TRACE("(%p) ref=%d\n", This, ref);
 776
 777     return ref;
 778 }
 779
 780 static ULONG WINAPI JSCaller_Release(IServiceProvider *iface)
 781 {
 782     JSCaller *This = impl_from_IServiceProvider(iface);
 783     LONG ref = InterlockedIncrement(&This->ref);
 784
 785     TRACE("(%p) ref=%d\n", This, ref);
 786
 787     if(!ref) {
 788         assert(!This->ctx);
 789         heap_free(This);
 790     }
 791
 792     return ref;
 793 }
 794
 795 static HRESULT WINAPI JSCaller_QueryService(IServiceProvider *iface, REFGUID guidService,
 796         REFIID riid, void **ppv)
 797 {
 798     JSCaller *This = impl_from_IServiceProvider(iface);
 799
 800     if(IsEqualGUID(guidService, &SID_VariantConversion) && This->ctx && This->ctx->active_script) {
 801         TRACE("(%p)->(SID_VariantConversion)\n", This);
 802         return IActiveScript_QueryInterface(This->ctx->active_script, riid, ppv);
 803     }
 804
 805     FIXME("(%p)->(%s %s %p)\n", This, debugstr_guid(guidService), debugstr_guid(riid), ppv);
 806
 807     *ppv = NULL;
 808     return E_NOINTERFACE;
 809 }
 810
 811 static const IServiceProviderVtbl ServiceProviderVtbl = {
 812     JSCaller_QueryInterface,
 813     JSCaller_AddRef,
 814     JSCaller_Release,
 815     JSCaller_QueryService
 816 };
 817
 818 HRESULT create_jscaller(script_ctx_t *ctx)
 819 {
 820     JSCaller *ret;
 821
 822     ret = heap_alloc(sizeof(*ret));
 823     if(!ret)
 824         return E_OUTOFMEMORY;
 825
 826     ret->IServiceProvider_iface.lpVtbl = &ServiceProviderVtbl;
 827     ret->ref = 1;
 828     ret->ctx = ctx;
 829
 830     ctx->jscaller = ret;
 831     return S_OK;
 832 }