dlls/urlmon/mimefilter.c

   1 /*
   2  * Copyright 2009 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 "urlmon_main.h"
  20 #include "wine/debug.h"
  21
  22 WINE_DEFAULT_DEBUG_CHANNEL(urlmon);
  23
  24 typedef struct {
  25     IInternetProtocol     IInternetProtocol_iface;
  26     IInternetProtocolSink IInternetProtocolSink_iface;
  27
  28     LONG ref;
  29 } MimeFilter;
  30
  31 static inline MimeFilter *impl_from_IInternetProtocol(IInternetProtocol *iface)
  32 {
  33     return CONTAINING_RECORD(iface, MimeFilter, IInternetProtocol_iface);
  34 }
  35
  36 static HRESULT WINAPI MimeFilterProtocol_QueryInterface(IInternetProtocol *iface, REFIID riid, void **ppv)
  37 {
  38     MimeFilter *This = impl_from_IInternetProtocol(iface);
  39
  40     *ppv = NULL;
  41     if(IsEqualGUID(&IID_IUnknown, riid)) {
  42         TRACE("(%p)->(IID_IUnknown %p)\n", This, ppv);
  43         *ppv = &This->IInternetProtocol_iface;
  44     }else if(IsEqualGUID(&IID_IInternetProtocolRoot, riid)) {
  45         TRACE("(%p)->(IID_IInternetProtocolRoot %p)\n", This, ppv);
  46         *ppv = &This->IInternetProtocol_iface;
  47     }else if(IsEqualGUID(&IID_IInternetProtocol, riid)) {
  48         TRACE("(%p)->(IID_IInternetProtocol %p)\n", This, ppv);
  49         *ppv = &This->IInternetProtocol_iface;
  50     }else if(IsEqualGUID(&IID_IInternetProtocolSink, riid)) {
  51         TRACE("(%p)->(IID_IInternetProtocolSink %p)\n", This, ppv);
  52         *ppv = &This->IInternetProtocolSink_iface;
  53     }
  54
  55     if(*ppv) {
  56         IInternetProtocol_AddRef(iface);
  57         return S_OK;
  58     }
  59
  60     WARN("not supported interface %s\n", debugstr_guid(riid));
  61     return E_NOINTERFACE;
  62 }
  63
  64 static ULONG WINAPI MimeFilterProtocol_AddRef(IInternetProtocol *iface)
  65 {
  66     MimeFilter *This = impl_from_IInternetProtocol(iface);
  67     LONG ref = InterlockedIncrement(&This->ref);
  68     TRACE("(%p) ref=%d\n", This, ref);
  69     return ref;
  70 }
  71
  72 static ULONG WINAPI MimeFilterProtocol_Release(IInternetProtocol *iface)
  73 {
  74     MimeFilter *This = impl_from_IInternetProtocol(iface);
  75     LONG ref = InterlockedDecrement(&This->ref);
  76
  77     TRACE("(%p) ref=%d\n", This, ref);
  78
  79     if(!ref) {
  80         heap_free(This);
  81
  82         URLMON_UnlockModule();
  83     }
  84
  85     return ref;
  86 }
  87
  88 static HRESULT WINAPI MimeFilterProtocol_Start(IInternetProtocol *iface, LPCWSTR szUrl,
  89         IInternetProtocolSink *pOIProtSink, IInternetBindInfo *pOIBindInfo,
  90         DWORD grfPI, HANDLE_PTR dwReserved)
  91 {
  92     MimeFilter *This = impl_from_IInternetProtocol(iface);
  93     FIXME("(%p)->(%s %p %p %08x %lx)\n", This, debugstr_w(szUrl), pOIProtSink,
  94           pOIBindInfo, grfPI, dwReserved);
  95     return E_NOTIMPL;
  96 }
  97
  98 static HRESULT WINAPI MimeFilterProtocol_Continue(IInternetProtocol *iface, PROTOCOLDATA *pProtocolData)
  99 {
 100     MimeFilter *This = impl_from_IInternetProtocol(iface);
 101     FIXME("(%p)->(%p)\n", This, pProtocolData);
 102     return E_NOTIMPL;
 103 }
 104
 105 static HRESULT WINAPI MimeFilterProtocol_Abort(IInternetProtocol *iface, HRESULT hrReason,
 106         DWORD dwOptions)
 107 {
 108     MimeFilter *This = impl_from_IInternetProtocol(iface);
 109     FIXME("(%p)->(%08x %08x)\n", This, hrReason, dwOptions);
 110     return E_NOTIMPL;
 111 }
 112
 113 static HRESULT WINAPI MimeFilterProtocol_Terminate(IInternetProtocol *iface, DWORD dwOptions)
 114 {
 115     MimeFilter *This = impl_from_IInternetProtocol(iface);
 116     FIXME("(%p)->(%08x)\n", This, dwOptions);
 117     return E_NOTIMPL;
 118 }
 119
 120 static HRESULT WINAPI MimeFilterProtocol_Suspend(IInternetProtocol *iface)
 121 {
 122     MimeFilter *This = impl_from_IInternetProtocol(iface);
 123     FIXME("(%p)\n", This);
 124     return E_NOTIMPL;
 125 }
 126
 127 static HRESULT WINAPI MimeFilterProtocol_Resume(IInternetProtocol *iface)
 128 {
 129     MimeFilter *This = impl_from_IInternetProtocol(iface);
 130     FIXME("(%p)\n", This);
 131     return E_NOTIMPL;
 132 }
 133
 134 static HRESULT WINAPI MimeFilterProtocol_Read(IInternetProtocol *iface, void *pv,
 135         ULONG cb, ULONG *pcbRead)
 136 {
 137     MimeFilter *This = impl_from_IInternetProtocol(iface);
 138     FIXME("(%p)->(%p %u %p)\n", This, pv, cb, pcbRead);
 139     return E_NOTIMPL;
 140 }
 141
 142 static HRESULT WINAPI MimeFilterProtocol_Seek(IInternetProtocol *iface, LARGE_INTEGER dlibMove,
 143         DWORD dwOrigin, ULARGE_INTEGER *plibNewPosition)
 144 {
 145     MimeFilter *This = impl_from_IInternetProtocol(iface);
 146     FIXME("(%p)->(%d %d %p)\n", This, dlibMove.u.LowPart, dwOrigin, plibNewPosition);
 147     return E_NOTIMPL;
 148 }
 149
 150 static HRESULT WINAPI MimeFilterProtocol_LockRequest(IInternetProtocol *iface, DWORD dwOptions)
 151 {
 152     MimeFilter *This = impl_from_IInternetProtocol(iface);
 153     FIXME("(%p)->(%08x)\n", This, dwOptions);
 154     return E_NOTIMPL;
 155 }
 156
 157 static HRESULT WINAPI MimeFilterProtocol_UnlockRequest(IInternetProtocol *iface)
 158 {
 159     MimeFilter *This = impl_from_IInternetProtocol(iface);
 160     FIXME("(%p)\n", This);
 161     return E_NOTIMPL;
 162 }
 163
 164 static const IInternetProtocolVtbl MimeFilterProtocolVtbl = {
 165     MimeFilterProtocol_QueryInterface,
 166     MimeFilterProtocol_AddRef,
 167     MimeFilterProtocol_Release,
 168     MimeFilterProtocol_Start,
 169     MimeFilterProtocol_Continue,
 170     MimeFilterProtocol_Abort,
 171     MimeFilterProtocol_Terminate,
 172     MimeFilterProtocol_Suspend,
 173     MimeFilterProtocol_Resume,
 174     MimeFilterProtocol_Read,
 175     MimeFilterProtocol_Seek,
 176     MimeFilterProtocol_LockRequest,
 177     MimeFilterProtocol_UnlockRequest
 178 };
 179
 180 static inline MimeFilter *impl_from_IInternetProtocolSink(IInternetProtocolSink *iface)
 181 {
 182     return CONTAINING_RECORD(iface, MimeFilter, IInternetProtocolSink_iface);
 183 }
 184
 185 static HRESULT WINAPI MimeFilterSink_QueryInterface(IInternetProtocolSink *iface,
 186         REFIID riid, void **ppv)
 187 {
 188     MimeFilter *This = impl_from_IInternetProtocolSink(iface);
 189     return IInternetProtocol_QueryInterface(&This->IInternetProtocol_iface, riid, ppv);
 190 }
 191
 192 static ULONG WINAPI MimeFilterSink_AddRef(IInternetProtocolSink *iface)
 193 {
 194     MimeFilter *This = impl_from_IInternetProtocolSink(iface);
 195     return IInternetProtocol_AddRef(&This->IInternetProtocol_iface);
 196 }
 197
 198 static ULONG WINAPI MimeFilterSink_Release(IInternetProtocolSink *iface)
 199 {
 200     MimeFilter *This = impl_from_IInternetProtocolSink(iface);
 201     return IInternetProtocol_Release(&This->IInternetProtocol_iface);
 202 }
 203
 204 static HRESULT WINAPI MimeFilterSink_Switch(IInternetProtocolSink *iface,
 205         PROTOCOLDATA *pProtocolData)
 206 {
 207     MimeFilter *This = impl_from_IInternetProtocolSink(iface);
 208     FIXME("(%p)->(%p)\n", This, pProtocolData);
 209     return E_NOTIMPL;
 210 }
 211
 212 static HRESULT WINAPI MimeFilterSink_ReportProgress(IInternetProtocolSink *iface,
 213         ULONG ulStatusCode, LPCWSTR szStatusText)
 214 {
 215     MimeFilter *This = impl_from_IInternetProtocolSink(iface);
 216     FIXME("(%p)->(%u %s)\n", This, ulStatusCode, debugstr_w(szStatusText));
 217     return E_NOTIMPL;
 218 }
 219
 220 static HRESULT WINAPI MimeFilterSink_ReportData(IInternetProtocolSink *iface,
 221         DWORD grfBSCF, ULONG ulProgress, ULONG ulProgressMax)
 222 {
 223     MimeFilter *This = impl_from_IInternetProtocolSink(iface);
 224     FIXME("(%p)->(%d %u %u)\n", This, grfBSCF, ulProgress, ulProgressMax);
 225     return E_NOTIMPL;
 226 }
 227
 228 static HRESULT WINAPI MimeFilterSink_ReportResult(IInternetProtocolSink *iface,
 229         HRESULT hrResult, DWORD dwError, LPCWSTR szResult)
 230 {
 231     MimeFilter *This = impl_from_IInternetProtocolSink(iface);
 232     FIXME("(%p)->(%08x %d %s)\n", This, hrResult, dwError, debugstr_w(szResult));
 233     return E_NOTIMPL;
 234 }
 235
 236 static const IInternetProtocolSinkVtbl InternetProtocolSinkVtbl = {
 237     MimeFilterSink_QueryInterface,
 238     MimeFilterSink_AddRef,
 239     MimeFilterSink_Release,
 240     MimeFilterSink_Switch,
 241     MimeFilterSink_ReportProgress,
 242     MimeFilterSink_ReportData,
 243     MimeFilterSink_ReportResult
 244 };
 245
 246 HRESULT MimeFilter_Construct(IUnknown *pUnkOuter, LPVOID *ppobj)
 247 {
 248     MimeFilter *ret;
 249
 250     TRACE("(%p %p)\n", pUnkOuter, ppobj);
 251
 252     URLMON_LockModule();
 253
 254     ret = heap_alloc_zero(sizeof(MimeFilter));
 255
 256     ret->IInternetProtocol_iface.lpVtbl = &MimeFilterProtocolVtbl;
 257     ret->IInternetProtocolSink_iface.lpVtbl = &InternetProtocolSinkVtbl;
 258     ret->ref = 1;
 259
 260     *ppobj = &ret->IInternetProtocol_iface;
 261     return S_OK;
 262 }
 263
 264 static BOOL text_richtext_filter(const BYTE *b, DWORD size)
 265 {
 266     return size > 5 && !memcmp(b, "{\\rtf", 5);
 267 }
 268
 269 static BOOL text_html_filter(const BYTE *b, DWORD size)
 270 {
 271     if(size < 6)
 272         return FALSE;
 273
 274     if((b[0] == '<'
 275                 && (b[1] == 'h' || b[1] == 'H')
 276                 && (b[2] == 't' || b[2] == 'T')
 277                 && (b[3] == 'm' || b[3] == 'M')
 278                 && (b[4] == 'l' || b[4] == 'L'))
 279             || (b[0] == '<'
 280                 && (b[1] == 'h' || b[1] == 'H')
 281                 && (b[2] == 'e' || b[2] == 'E')
 282                 && (b[3] == 'a' || b[3] == 'A')
 283                 && (b[4] == 'd' || b[4] == 'D'))
 284             || (b[0] == '<'
 285                 && (b[1] == 'b' || b[1] == 'B')
 286                 && (b[2] == 'o' || b[2] == 'O')
 287                 && (b[3] == 'd' || b[3] == 'D')
 288                 && (b[4] == 'y' || b[4] == 'Y'))) return TRUE;
 289
 290     return FALSE;
 291 }
 292
 293 static BOOL text_xml_filter(const BYTE *b, DWORD size)
 294 {
 295     if(size < 7)
 296         return FALSE;
 297
 298     if(b[0] == '<' && b[1] == '?'
 299             && (b[2] == 'x' || b[2] == 'X')
 300             && (b[3] == 'm' || b[3] == 'M')
 301             && (b[4] == 'l' || b[4] == 'L')
 302             && b[5] == ' ') return TRUE;
 303
 304     return FALSE;
 305 }
 306
 307 static BOOL audio_basic_filter(const BYTE *b, DWORD size)
 308 {
 309     return size > 4
 310         && b[0] == '.' && b[1] == 's' && b[2] == 'n' && b[3] == 'd';
 311 }
 312
 313 static BOOL audio_wav_filter(const BYTE *b, DWORD size)
 314 {
 315     return size > 12
 316         && b[0] == 'R' && b[1] == 'I' && b[2] == 'F' && b[3] == 'F'
 317         && b[8] == 'W' && b[9] == 'A' && b[10] == 'V' && b[11] == 'E';
 318 }
 319
 320 static BOOL image_gif_filter(const BYTE *b, DWORD size)
 321 {
 322     return size >= 6
 323         && (b[0] == 'G' || b[0] == 'g')
 324         && (b[1] == 'I' || b[1] == 'i')
 325         && (b[2] == 'F' || b[2] == 'f')
 326         &&  b[3] == '8'
 327         && (b[4] == '7' || b[4] == '9')
 328         && (b[5] == 'A' || b[5] == 'a');
 329 }
 330
 331 static BOOL image_pjpeg_filter(const BYTE *b, DWORD size)
 332 {
 333     return size > 2 && b[0] == 0xff && b[1] == 0xd8;
 334 }
 335
 336 static BOOL image_tiff_filter(const BYTE *b, DWORD size)
 337 {
 338     static const BYTE magic1[] = {0x4d,0x4d,0x00,0x2a};
 339     static const BYTE magic2[] = {0x49,0x49,0x2a,0xff};
 340
 341     return size >= 4 && (!memcmp(b, magic1, 4) || !memcmp(b, magic2, 4));
 342 }
 343
 344 static BOOL image_xpng_filter(const BYTE *b, DWORD size)
 345 {
 346     static const BYTE xpng_header[] = {0x89,'P','N','G',0x0d,0x0a,0x1a,0x0a};
 347     return size > sizeof(xpng_header) && !memcmp(b, xpng_header, sizeof(xpng_header));
 348 }
 349
 350 static BOOL image_bmp_filter(const BYTE *b, DWORD size)
 351 {
 352     return size >= 14
 353         && b[0] == 0x42 && b[1] == 0x4d
 354         && *(const DWORD *)(b+6) == 0;
 355 }
 356
 357 static BOOL video_avi_filter(const BYTE *b, DWORD size)
 358 {
 359     return size > 12
 360         && b[0] == 'R' && b[1] == 'I' && b[2] == 'F' && b[3] == 'F'
 361         && b[8] == 'A' && b[9] == 'V' && b[10] == 'I' && b[11] == 0x20;
 362 }
 363
 364 static BOOL video_mpeg_filter(const BYTE *b, DWORD size)
 365 {
 366     return size > 4
 367         && !b[0] && !b[1] && b[2] == 0x01
 368         && (b[3] == 0xb3 || b[3] == 0xba);
 369 }
 370
 371 static BOOL application_postscript_filter(const BYTE *b, DWORD size)
 372 {
 373     return size > 2 && b[0] == '%' && b[1] == '!';
 374 }
 375
 376 static BOOL application_pdf_filter(const BYTE *b, DWORD size)
 377 {
 378     return size > 4 && b[0] == 0x25 && b[1] == 0x50 && b[2] == 0x44 && b[3] == 0x46;
 379 }
 380
 381 static BOOL application_xzip_filter(const BYTE *b, DWORD size)
 382 {
 383     return size > 2 && b[0] == 0x50 && b[1] == 0x4b;
 384 }
 385
 386 static BOOL application_xgzip_filter(const BYTE *b, DWORD size)
 387 {
 388     return size > 2 && b[0] == 0x1f && b[1] == 0x8b;
 389 }
 390
 391 static BOOL application_java_filter(const BYTE *b, DWORD size)
 392 {
 393     return size > 4 && b[0] == 0xca && b[1] == 0xfe && b[2] == 0xba && b[3] == 0xbe;
 394 }
 395
 396 static BOOL application_xmsdownload(const BYTE *b, DWORD size)
 397 {
 398     return size > 2 && b[0] == 'M' && b[1] == 'Z';
 399 }
 400
 401 static inline BOOL is_text_plain_char(BYTE b)
 402 {
 403     if(b < 0x20 && b != '\n' && b != '\r' && b != '\t')
 404         return FALSE;
 405     return TRUE;
 406 }
 407
 408 static BOOL text_plain_filter(const BYTE *b, DWORD size)
 409 {
 410     const BYTE *ptr;
 411
 412     for(ptr = b; ptr < b+size-1; ptr++) {
 413         if(!is_text_plain_char(*ptr))
 414             return FALSE;
 415     }
 416
 417     return TRUE;
 418 }
 419
 420 static BOOL application_octet_stream_filter(const BYTE *b, DWORD size)
 421 {
 422     return TRUE;
 423 }
 424
 425 HRESULT find_mime_from_ext(const WCHAR *ext, WCHAR **ret)
 426 {
 427     DWORD res, size;
 428     WCHAR mime[64];
 429     HKEY hkey;
 430
 431     res = RegOpenKeyW(HKEY_CLASSES_ROOT, ext, &hkey);
 432     if(res != ERROR_SUCCESS)
 433         return HRESULT_FROM_WIN32(res);
 434
 435     size = sizeof(mime);
 436     res = RegQueryValueExW(hkey, L"Content Type", NULL, NULL, (BYTE*)mime, &size);
 437     RegCloseKey(hkey);
 438     if(res != ERROR_SUCCESS)
 439         return HRESULT_FROM_WIN32(res);
 440
 441     TRACE("found MIME %s\n", debugstr_w(mime));
 442
 443     *ret = CoTaskMemAlloc(size);
 444     memcpy(*ret, mime, size);
 445     return S_OK;
 446 }
 447
 448 static HRESULT find_mime_from_url(const WCHAR *url, WCHAR **ret)
 449 {
 450     const WCHAR *ptr, *end_ptr;
 451     WCHAR *ext = NULL;
 452     HRESULT hres;
 453
 454     for(end_ptr = url; *end_ptr; end_ptr++) {
 455         if(*end_ptr == '?' || *end_ptr == '#')
 456             break;
 457     }
 458
 459     for(ptr = end_ptr; ptr >= url; ptr--) {
 460         if(*ptr == '.')
 461             break;
 462     }
 463
 464     if(ptr < url)
 465         return E_FAIL;
 466
 467     if(*end_ptr) {
 468         unsigned len = end_ptr-ptr;
 469
 470         ext = heap_alloc((len+1)*sizeof(WCHAR));
 471         if(!ext)
 472             return E_OUTOFMEMORY;
 473
 474         memcpy(ext, ptr, len*sizeof(WCHAR));
 475         ext[len] = 0;
 476     }
 477
 478     hres = find_mime_from_ext(ext ? ext : ptr, ret);
 479     heap_free(ext);
 480     return hres;
 481 }
 482
 483 static const WCHAR text_plainW[] = L"text/plain";
 484 static const WCHAR app_octetstreamW[] = L"application/octet-stream";
 485
 486 static const struct {
 487     const WCHAR *mime;
 488     BOOL (*filter)(const BYTE *,DWORD);
 489 } mime_filters_any_pos[] = {
 490     {L"text/html",       text_html_filter},
 491     {L"text/xml",        text_xml_filter}
 492 }, mime_filters[] = {
 493     {L"text/richtext",   text_richtext_filter},
 494  /* {L"audio/x-aiff",    audio_xaiff_filter}, */
 495     {L"audio/basic",     audio_basic_filter},
 496     {L"audio/wav",       audio_wav_filter},
 497     {L"image/gif",       image_gif_filter},
 498     {L"image/pjpeg",     image_pjpeg_filter},
 499     {L"image/tiff",      image_tiff_filter},
 500     {L"image/x-png",     image_xpng_filter},
 501  /* {L"image/x-bitmap",  image_xbitmap_filter}, */
 502     {L"image/bmp",       image_bmp_filter},
 503  /* {L"image/x-jg",      image_xjg_filter}, */
 504  /* {L"image/x-emf",     image_xemf_filter}, */
 505  /* {L"image/x-wmf",     image_xwmf_filter}, */
 506     {L"video/avi",       video_avi_filter},
 507     {L"video/mpeg",      video_mpeg_filter},
 508     {L"application/postscript",         application_postscript_filter},
 509  /* {L"application/base64",             application_base64_filter}, */
 510  /* {L"application/mac-binhex40",       application_macbinhex40_filter}, */
 511     {L"application/pdf",                application_pdf_filter},
 512  /* {L"application/x-compressed",       application_xcompressed_filter}, */
 513     {L"application/x-zip-compressed",   application_xzip_filter},
 514     {L"application/x-gzip-compressed",  application_xgzip_filter},
 515     {L"application/java",               application_java_filter},
 516     {L"application/x-msdownload",       application_xmsdownload},
 517     {text_plainW,      text_plain_filter},
 518     {app_octetstreamW, application_octet_stream_filter}
 519 };
 520
 521 static BOOL is_known_mime_type(const WCHAR *mime)
 522 {
 523     unsigned i;
 524
 525     for(i=0; i < ARRAY_SIZE(mime_filters_any_pos); i++) {
 526         if(!wcscmp(mime, mime_filters_any_pos[i].mime))
 527             return TRUE;
 528     }
 529
 530     for(i=0; i < ARRAY_SIZE(mime_filters); i++) {
 531         if(!wcscmp(mime, mime_filters[i].mime))
 532             return TRUE;
 533     }
 534
 535     return FALSE;
 536 }
 537
 538 static HRESULT find_mime_from_buffer(const BYTE *buf, DWORD size, const WCHAR *proposed_mime, const WCHAR *url, WCHAR **ret_mime)
 539 {
 540     int len, i, any_pos_mime = -1;
 541     const WCHAR *ret = NULL;
 542
 543     if(!buf || !size) {
 544         if(!proposed_mime)
 545             return E_FAIL;
 546
 547         len = lstrlenW(proposed_mime)+1;
 548         *ret_mime = CoTaskMemAlloc(len*sizeof(WCHAR));
 549         if(!*ret_mime)
 550             return E_OUTOFMEMORY;
 551
 552         memcpy(*ret_mime, proposed_mime, len*sizeof(WCHAR));
 553         return S_OK;
 554     }
 555
 556     if(proposed_mime && (!wcscmp(proposed_mime, app_octetstreamW)
 557                 || !wcscmp(proposed_mime, text_plainW)))
 558         proposed_mime = NULL;
 559
 560     if(proposed_mime) {
 561         ret = proposed_mime;
 562
 563         for(i=0; i < ARRAY_SIZE(mime_filters_any_pos); i++) {
 564             if(!wcscmp(proposed_mime, mime_filters_any_pos[i].mime)) {
 565                 any_pos_mime = i;
 566                 for(len=size; len>0; len--) {
 567                     if(mime_filters_any_pos[i].filter(buf+size-len, len))
 568                         break;
 569                 }
 570                 if(!len)
 571                     ret = NULL;
 572                 break;
 573             }
 574         }
 575
 576         if(i == ARRAY_SIZE(mime_filters_any_pos)) {
 577             for(i=0; i < ARRAY_SIZE(mime_filters); i++) {
 578                 if(!wcscmp(proposed_mime, mime_filters[i].mime)) {
 579                     if(!mime_filters[i].filter(buf, size))
 580                         ret = NULL;
 581                     break;
 582                 }
 583             }
 584         }
 585     }
 586
 587     /* Looks like a bug in native implementation, html and xml mimes
 588      * are not looked for if none of them was proposed */
 589     if(!proposed_mime || any_pos_mime!=-1) {
 590         for(len=size; !ret && len>0; len--) {
 591             for(i=0; i<ARRAY_SIZE(mime_filters_any_pos); i++) {
 592                 if(mime_filters_any_pos[i].filter(buf+size-len, len)) {
 593                     ret = mime_filters_any_pos[i].mime;
 594                     break;
 595                 }
 596             }
 597         }
 598     }
 599
 600     i=0;
 601     while(!ret) {
 602         if(mime_filters[i].filter(buf, size))
 603             ret = mime_filters[i].mime;
 604         i++;
 605     }
 606
 607     if(any_pos_mime!=-1 && ret==text_plainW)
 608         ret = mime_filters_any_pos[any_pos_mime].mime;
 609     else if(proposed_mime && ret==app_octetstreamW) {
 610         for(len=size; ret==app_octetstreamW && len>0; len--) {
 611             if(!is_text_plain_char(buf[size-len]))
 612                 break;
 613             for(i=0; i<ARRAY_SIZE(mime_filters_any_pos); i++) {
 614                 if(mime_filters_any_pos[i].filter(buf+size-len, len)) {
 615                     ret = text_plainW;
 616                     break;
 617                 }
 618             }
 619         }
 620
 621         if(ret == app_octetstreamW)
 622             ret = proposed_mime;
 623     }
 624
 625     if(url && (ret == app_octetstreamW || ret == text_plainW)) {
 626         WCHAR *url_mime;
 627         HRESULT hres;
 628
 629         hres = find_mime_from_url(url, &url_mime);
 630         if(SUCCEEDED(hres)) {
 631             if(!is_known_mime_type(url_mime)) {
 632                 *ret_mime = url_mime;
 633                 return hres;
 634             }
 635             CoTaskMemFree(url_mime);
 636         }
 637     }
 638
 639     TRACE("found %s for %s\n", debugstr_w(ret), debugstr_an((const char*)buf, min(32, size)));
 640
 641     len = lstrlenW(ret)+1;
 642     *ret_mime = CoTaskMemAlloc(len*sizeof(WCHAR));
 643     if(!*ret_mime)
 644         return E_OUTOFMEMORY;
 645
 646     memcpy(*ret_mime, ret, len*sizeof(WCHAR));
 647     return S_OK;
 648 }
 649
 650 /***********************************************************************
 651  *           FindMimeFromData (URLMON.@)
 652  *
 653  * Determines the Multipurpose Internet Mail Extensions (MIME) type from the data provided.
 654  */
 655 HRESULT WINAPI FindMimeFromData(LPBC pBC, LPCWSTR pwzUrl, LPVOID pBuffer,
 656         DWORD cbSize, LPCWSTR pwzMimeProposed, DWORD dwMimeFlags,
 657         LPWSTR* ppwzMimeOut, DWORD dwReserved)
 658 {
 659     TRACE("(%p,%s,%p,%d,%s,0x%x,%p,0x%x)\n", pBC, debugstr_w(pwzUrl), pBuffer, cbSize,
 660             debugstr_w(pwzMimeProposed), dwMimeFlags, ppwzMimeOut, dwReserved);
 661
 662     if(dwMimeFlags)
 663         WARN("dwMimeFlags=%08x\n", dwMimeFlags);
 664     if(dwReserved)
 665         WARN("dwReserved=%d\n", dwReserved);
 666
 667     /* pBC seems to not be used */
 668
 669     if(!ppwzMimeOut || (!pwzUrl && !pBuffer))
 670         return E_INVALIDARG;
 671
 672     if(pwzMimeProposed || pBuffer)
 673         return find_mime_from_buffer(pBuffer, cbSize, pwzMimeProposed, pwzUrl, ppwzMimeOut);
 674
 675     return find_mime_from_url(pwzUrl, ppwzMimeOut);
 676 }