third_party/harfbuzz-ng/src/hb-uniscribe.cc

   1 /*
   2  * Copyright © 2011,2012,2013  Google, Inc.
   3  *
   4  *  This is part of HarfBuzz, a text shaping library.
   5  *
   6  * Permission is hereby granted, without written agreement and without
   7  * license or royalty fees, to use, copy, modify, and distribute this
   8  * software and its documentation for any purpose, provided that the
   9  * above copyright notice and the following two paragraphs appear in
  10  * all copies of this software.
  11  *
  12  * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
  13  * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
  14  * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
  15  * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
  16  * DAMAGE.
  17  *
  18  * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
  19  * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
  20  * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
  21  * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
  22  * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
  23  *
  24  * Google Author(s): Behdad Esfahbod
  25  */
  26
  27 #define _WIN32_WINNT 0x0600
  28 #define WIN32_LEAN_AND_MEAN
  29
  30 #define HB_SHAPER uniscribe
  31 #include "hb-shaper-impl-private.hh"
  32
  33 #include <windows.h>
  34 #include <usp10.h>
  35 #include <rpc.h>
  36
  37 #include "hb-uniscribe.h"
  38
  39 #include "hb-open-file-private.hh"
  40 #include "hb-ot-name-table.hh"
  41 #include "hb-ot-tag.h"
  42
  43
  44 #ifndef HB_DEBUG_UNISCRIBE
  45 #define HB_DEBUG_UNISCRIBE (HB_DEBUG+0)
  46 #endif
  47
  48
  49 typedef HRESULT (WINAPI *SIOT) /*ScriptItemizeOpenType*/(
  50   const WCHAR *pwcInChars,
  51   int cInChars,
  52   int cMaxItems,
  53   const SCRIPT_CONTROL *psControl,
  54   const SCRIPT_STATE *psState,
  55   SCRIPT_ITEM *pItems,
  56   OPENTYPE_TAG *pScriptTags,
  57   int *pcItems
  58 );
  59
  60 typedef HRESULT (WINAPI *SSOT) /*ScriptShapeOpenType*/(
  61   HDC hdc,
  62   SCRIPT_CACHE *psc,
  63   SCRIPT_ANALYSIS *psa,
  64   OPENTYPE_TAG tagScript,
  65   OPENTYPE_TAG tagLangSys,
  66   int *rcRangeChars,
  67   TEXTRANGE_PROPERTIES **rpRangeProperties,
  68   int cRanges,
  69   const WCHAR *pwcChars,
  70   int cChars,
  71   int cMaxGlyphs,
  72   WORD *pwLogClust,
  73   SCRIPT_CHARPROP *pCharProps,
  74   WORD *pwOutGlyphs,
  75   SCRIPT_GLYPHPROP *pOutGlyphProps,
  76   int *pcGlyphs
  77 );
  78
  79 typedef HRESULT (WINAPI *SPOT) /*ScriptPlaceOpenType*/(
  80   HDC hdc,
  81   SCRIPT_CACHE *psc,
  82   SCRIPT_ANALYSIS *psa,
  83   OPENTYPE_TAG tagScript,
  84   OPENTYPE_TAG tagLangSys,
  85   int *rcRangeChars,
  86   TEXTRANGE_PROPERTIES **rpRangeProperties,
  87   int cRanges,
  88   const WCHAR *pwcChars,
  89   WORD *pwLogClust,
  90   SCRIPT_CHARPROP *pCharProps,
  91   int cChars,
  92   const WORD *pwGlyphs,
  93   const SCRIPT_GLYPHPROP *pGlyphProps,
  94   int cGlyphs,
  95   int *piAdvance,
  96   GOFFSET *pGoffset,
  97   ABC *pABC
  98 );
  99
 100
 101 /* Fallback implementations. */
 102
 103 static HRESULT WINAPI
 104 hb_ScriptItemizeOpenType(
 105   const WCHAR *pwcInChars,
 106   int cInChars,
 107   int cMaxItems,
 108   const SCRIPT_CONTROL *psControl,
 109   const SCRIPT_STATE *psState,
 110   SCRIPT_ITEM *pItems,
 111   OPENTYPE_TAG *pScriptTags,
 112   int *pcItems
 113 )
 114 {
 115 {
 116   return ScriptItemize (pwcInChars,
 117                         cInChars,
 118                         cMaxItems,
 119                         psControl,
 120                         psState,
 121                         pItems,
 122                         pcItems);
 123 }
 124 }
 125
 126 static HRESULT WINAPI
 127 hb_ScriptShapeOpenType(
 128   HDC hdc,
 129   SCRIPT_CACHE *psc,
 130   SCRIPT_ANALYSIS *psa,
 131   OPENTYPE_TAG tagScript,
 132   OPENTYPE_TAG tagLangSys,
 133   int *rcRangeChars,
 134   TEXTRANGE_PROPERTIES **rpRangeProperties,
 135   int cRanges,
 136   const WCHAR *pwcChars,
 137   int cChars,
 138   int cMaxGlyphs,
 139   WORD *pwLogClust,
 140   SCRIPT_CHARPROP *pCharProps,
 141   WORD *pwOutGlyphs,
 142   SCRIPT_GLYPHPROP *pOutGlyphProps,
 143   int *pcGlyphs
 144 )
 145 {
 146   SCRIPT_VISATTR *psva = (SCRIPT_VISATTR *) pOutGlyphProps;
 147   return ScriptShape (hdc,
 148                       psc,
 149                       pwcChars,
 150                       cChars,
 151                       cMaxGlyphs,
 152                       psa,
 153                       pwOutGlyphs,
 154                       pwLogClust,
 155                       psva,
 156                       pcGlyphs);
 157 }
 158
 159 static HRESULT WINAPI
 160 hb_ScriptPlaceOpenType(
 161   HDC hdc,
 162   SCRIPT_CACHE *psc,
 163   SCRIPT_ANALYSIS *psa,
 164   OPENTYPE_TAG tagScript,
 165   OPENTYPE_TAG tagLangSys,
 166   int *rcRangeChars,
 167   TEXTRANGE_PROPERTIES **rpRangeProperties,
 168   int cRanges,
 169   const WCHAR *pwcChars,
 170   WORD *pwLogClust,
 171   SCRIPT_CHARPROP *pCharProps,
 172   int cChars,
 173   const WORD *pwGlyphs,
 174   const SCRIPT_GLYPHPROP *pGlyphProps,
 175   int cGlyphs,
 176   int *piAdvance,
 177   GOFFSET *pGoffset,
 178   ABC *pABC
 179 )
 180 {
 181   SCRIPT_VISATTR *psva = (SCRIPT_VISATTR *) pGlyphProps;
 182   return ScriptPlace (hdc,
 183                       psc,
 184                       pwGlyphs,
 185                       cGlyphs,
 186                       psva,
 187                       psa,
 188                       piAdvance,
 189                       pGoffset,
 190                       pABC);
 191 }
 192
 193
 194 struct hb_uniscribe_shaper_funcs_t {
 195   SIOT ScriptItemizeOpenType;
 196   SSOT ScriptShapeOpenType;
 197   SPOT ScriptPlaceOpenType;
 198
 199   inline void init (void)
 200   {
 201     HMODULE hinstLib;
 202     this->ScriptItemizeOpenType = NULL;
 203     this->ScriptShapeOpenType   = NULL;
 204     this->ScriptPlaceOpenType   = NULL;
 205
 206     hinstLib = GetModuleHandle (TEXT ("usp10.dll"));
 207     if (hinstLib)
 208     {
 209       this->ScriptItemizeOpenType = (SIOT) GetProcAddress (hinstLib, "ScriptItemizeOpenType");
 210       this->ScriptShapeOpenType   = (SSOT) GetProcAddress (hinstLib, "ScriptShapeOpenType");
 211       this->ScriptPlaceOpenType   = (SPOT) GetProcAddress (hinstLib, "ScriptPlaceOpenType");
 212     }
 213     if (!this->ScriptItemizeOpenType ||
 214         !this->ScriptShapeOpenType   ||
 215         !this->ScriptPlaceOpenType)
 216     {
 217       DEBUG_MSG (UNISCRIBE, NULL, "OpenType versions of functions not found; falling back.");
 218       this->ScriptItemizeOpenType = hb_ScriptItemizeOpenType;
 219       this->ScriptShapeOpenType   = hb_ScriptShapeOpenType;
 220       this->ScriptPlaceOpenType   = hb_ScriptPlaceOpenType;
 221     }
 222   }
 223 };
 224 static hb_uniscribe_shaper_funcs_t *uniscribe_funcs;
 225
 226 static inline void
 227 free_uniscribe_funcs (void)
 228 {
 229   free (uniscribe_funcs);
 230 }
 231
 232 static hb_uniscribe_shaper_funcs_t *
 233 hb_uniscribe_shaper_get_funcs (void)
 234 {
 235 retry:
 236   hb_uniscribe_shaper_funcs_t *funcs = (hb_uniscribe_shaper_funcs_t *) hb_atomic_ptr_get (&uniscribe_funcs);
 237
 238   if (unlikely (!funcs))
 239   {
 240     funcs = (hb_uniscribe_shaper_funcs_t *) calloc (1, sizeof (hb_uniscribe_shaper_funcs_t));
 241     if (unlikely (!funcs))
 242       return NULL;
 243
 244     funcs->init ();
 245
 246     if (!hb_atomic_ptr_cmpexch (&uniscribe_funcs, NULL, funcs)) {
 247       free (funcs);
 248       goto retry;
 249     }
 250
 251 #ifdef HAVE_ATEXIT
 252     atexit (free_uniscribe_funcs); /* First person registers atexit() callback. */
 253 #endif
 254   }
 255
 256   return funcs;
 257 }
 258
 259
 260 struct active_feature_t {
 261   OPENTYPE_FEATURE_RECORD rec;
 262   unsigned int order;
 263
 264   static int cmp (const active_feature_t *a, const active_feature_t *b) {
 265     return a->rec.tagFeature < b->rec.tagFeature ? -1 : a->rec.tagFeature > b->rec.tagFeature ? 1 :
 266            a->order < b->order ? -1 : a->order > b->order ? 1 :
 267            a->rec.lParameter < b->rec.lParameter ? -1 : a->rec.lParameter > b->rec.lParameter ? 1 :
 268            0;
 269   }
 270   bool operator== (const active_feature_t *f) {
 271     return cmp (this, f) == 0;
 272   }
 273 };
 274
 275 struct feature_event_t {
 276   unsigned int index;
 277   bool start;
 278   active_feature_t feature;
 279
 280   static int cmp (const feature_event_t *a, const feature_event_t *b) {
 281     return a->index < b->index ? -1 : a->index > b->index ? 1 :
 282            a->start < b->start ? -1 : a->start > b->start ? 1 :
 283            active_feature_t::cmp (&a->feature, &b->feature);
 284   }
 285 };
 286
 287 struct range_record_t {
 288   TEXTRANGE_PROPERTIES props;
 289   unsigned int index_first; /* == start */
 290   unsigned int index_last;  /* == end - 1 */
 291 };
 292
 293 HB_SHAPER_DATA_ENSURE_DECLARE(uniscribe, face)
 294 HB_SHAPER_DATA_ENSURE_DECLARE(uniscribe, font)
 295
 296
 297 /*
 298  * shaper face data
 299  */
 300
 301 struct hb_uniscribe_shaper_face_data_t {
 302   HANDLE fh;
 303   hb_uniscribe_shaper_funcs_t *funcs;
 304   wchar_t face_name[LF_FACESIZE];
 305 };
 306
 307 /* face_name should point to a wchar_t[LF_FACESIZE] object. */
 308 static void
 309 _hb_generate_unique_face_name (wchar_t *face_name, unsigned int *plen)
 310 {
 311   /* We'll create a private name for the font from a UUID using a simple,
 312    * somewhat base64-like encoding scheme */
 313   const char *enc = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+-";
 314   UUID id;
 315   UuidCreate ((UUID*) &id);
 316   unsigned int name_str_len = 0;
 317   face_name[name_str_len++] = 'F';
 318   face_name[name_str_len++] = '_';
 319   unsigned char *p = (unsigned char *) &id;
 320   for (unsigned int i = 0; i < 16; i += 2)
 321   {
 322     /* Spread the 16 bits from two bytes of the UUID across three chars of face_name,
 323      * using the bits in groups of 5,5,6 to select chars from enc.
 324      * This will generate 24 characters; with the 'F_' prefix we already provided,
 325      * the name will be 26 chars (plus the NUL terminator), so will always fit within
 326      * face_name (LF_FACESIZE = 32). */
 327     face_name[name_str_len++] = enc[p[i] >> 3];
 328     face_name[name_str_len++] = enc[((p[i] << 2) | (p[i + 1] >> 6)) & 0x1f];
 329     face_name[name_str_len++] = enc[p[i + 1] & 0x3f];
 330   }
 331   face_name[name_str_len] = 0;
 332   if (plen)
 333     *plen = name_str_len;
 334 }
 335
 336 /* Destroys blob. */
 337 static hb_blob_t *
 338 _hb_rename_font (hb_blob_t *blob, wchar_t *new_name)
 339 {
 340   /* Create a copy of the font data, with the 'name' table replaced by a
 341    * table that names the font with our private F_* name created above.
 342    * For simplicity, we just append a new 'name' table and update the
 343    * sfnt directory; the original table is left in place, but unused.
 344    *
 345    * The new table will contain just 5 name IDs: family, style, unique,
 346    * full, PS. All of them point to the same name data with our unique name.
 347    */
 348
 349   blob = OT::Sanitizer<OT::OpenTypeFontFile>::sanitize (blob);
 350
 351   unsigned int length, new_length, name_str_len;
 352   const char *orig_sfnt_data = hb_blob_get_data (blob, &length);
 353
 354   _hb_generate_unique_face_name (new_name, &name_str_len);
 355
 356   static const uint16_t name_IDs[] = { 1, 2, 3, 4, 6 };
 357
 358   unsigned int name_table_length = OT::name::min_size +
 359                                    ARRAY_LENGTH (name_IDs) * OT::NameRecord::static_size +
 360                                    name_str_len * 2; /* for name data in UTF16BE form */
 361   unsigned int name_table_offset = (length + 3) & ~3;
 362
 363   new_length = name_table_offset + ((name_table_length + 3) & ~3);
 364   void *new_sfnt_data = calloc (1, new_length);
 365   if (!new_sfnt_data)
 366   {
 367     hb_blob_destroy (blob);
 368     return NULL;
 369   }
 370
 371   memcpy(new_sfnt_data, orig_sfnt_data, length);
 372
 373   OT::name &name = OT::StructAtOffset<OT::name> (new_sfnt_data, name_table_offset);
 374   name.format.set (0);
 375   name.count.set (ARRAY_LENGTH (name_IDs));
 376   name.stringOffset.set (name.get_size ());
 377   for (unsigned int i = 0; i < ARRAY_LENGTH (name_IDs); i++)
 378   {
 379     OT::NameRecord &record = name.nameRecord[i];
 380     record.platformID.set (3);
 381     record.encodingID.set (1);
 382     record.languageID.set (0x0409); /* English */
 383     record.nameID.set (name_IDs[i]);
 384     record.length.set (name_str_len * 2);
 385     record.offset.set (0);
 386   }
 387
 388   /* Copy string data from new_name, converting wchar_t to UTF16BE. */
 389   unsigned char *p = &OT::StructAfter<unsigned char> (name);
 390   for (unsigned int i = 0; i < name_str_len; i++)
 391   {
 392     *p++ = new_name[i] >> 8;
 393     *p++ = new_name[i] & 0xff;
 394   }
 395
 396   /* Adjust name table entry to point to new name table */
 397   const OT::OpenTypeFontFile &file = * (OT::OpenTypeFontFile *) (new_sfnt_data);
 398   unsigned int face_count = file.get_face_count ();
 399   for (unsigned int face_index = 0; face_index < face_count; face_index++)
 400   {
 401     /* Note: doing multiple edits (ie. TTC) can be unsafe.  There may be
 402      * toe-stepping.  But we don't really care. */
 403     const OT::OpenTypeFontFace &face = file.get_face (face_index);
 404     unsigned int index;
 405     if (face.find_table_index (HB_OT_TAG_name, &index))
 406     {
 407       OT::TableRecord &record = const_cast<OT::TableRecord &> (face.get_table (index));
 408       record.checkSum.set_for_data (&name, name_table_length);
 409       record.offset.set (name_table_offset);
 410       record.length.set (name_table_length);
 411     }
 412     else if (face_index == 0) /* Fail if first face doesn't have 'name' table. */
 413     {
 414       free (new_sfnt_data);
 415       hb_blob_destroy (blob);
 416       return NULL;
 417     }
 418   }
 419
 420   /* The checkSumAdjustment field in the 'head' table is now wrong,
 421    * but that doesn't actually seem to cause any problems so we don't
 422    * bother. */
 423
 424   hb_blob_destroy (blob);
 425   return hb_blob_create ((const char *) new_sfnt_data, new_length,
 426                          HB_MEMORY_MODE_WRITABLE, NULL, free);
 427 }
 428
 429 hb_uniscribe_shaper_face_data_t *
 430 _hb_uniscribe_shaper_face_data_create (hb_face_t *face)
 431 {
 432   hb_uniscribe_shaper_face_data_t *data = (hb_uniscribe_shaper_face_data_t *) calloc (1, sizeof (hb_uniscribe_shaper_face_data_t));
 433   if (unlikely (!data))
 434     return NULL;
 435
 436   data->funcs = hb_uniscribe_shaper_get_funcs ();
 437   if (unlikely (!data->funcs))
 438   {
 439     free (data);
 440     return NULL;
 441   }
 442
 443   hb_blob_t *blob = hb_face_reference_blob (face);
 444   if (unlikely (!hb_blob_get_length (blob)))
 445     DEBUG_MSG (UNISCRIBE, face, "Face has empty blob");
 446
 447   blob = _hb_rename_font (blob, data->face_name);
 448   if (unlikely (!blob))
 449   {
 450     free (data);
 451     return NULL;
 452   }
 453
 454   DWORD num_fonts_installed;
 455   data->fh = AddFontMemResourceEx ((void *) hb_blob_get_data (blob, NULL),
 456                                    hb_blob_get_length (blob),
 457                                    0, &num_fonts_installed);
 458   if (unlikely (!data->fh))
 459   {
 460     DEBUG_MSG (UNISCRIBE, face, "Face AddFontMemResourceEx() failed");
 461     free (data);
 462     return NULL;
 463   }
 464
 465   return data;
 466 }
 467
 468 void
 469 _hb_uniscribe_shaper_face_data_destroy (hb_uniscribe_shaper_face_data_t *data)
 470 {
 471   RemoveFontMemResourceEx (data->fh);
 472   free (data);
 473 }
 474
 475
 476 /*
 477  * shaper font data
 478  */
 479
 480 struct hb_uniscribe_shaper_font_data_t {
 481   HDC hdc;
 482   LOGFONTW log_font;
 483   HFONT hfont;
 484   SCRIPT_CACHE script_cache;
 485 };
 486
 487 static bool
 488 populate_log_font (LOGFONTW  *lf,
 489                    hb_font_t *font)
 490 {
 491   memset (lf, 0, sizeof (*lf));
 492   lf->lfHeight = -font->y_scale;
 493   lf->lfCharSet = DEFAULT_CHARSET;
 494
 495   hb_face_t *face = font->face;
 496   hb_uniscribe_shaper_face_data_t *face_data = HB_SHAPER_DATA_GET (face);
 497
 498   memcpy (lf->lfFaceName, face_data->face_name, sizeof (lf->lfFaceName));
 499
 500   return true;
 501 }
 502
 503 hb_uniscribe_shaper_font_data_t *
 504 _hb_uniscribe_shaper_font_data_create (hb_font_t *font)
 505 {
 506   if (unlikely (!hb_uniscribe_shaper_face_data_ensure (font->face))) return NULL;
 507
 508   hb_uniscribe_shaper_font_data_t *data = (hb_uniscribe_shaper_font_data_t *) calloc (1, sizeof (hb_uniscribe_shaper_font_data_t));
 509   if (unlikely (!data))
 510     return NULL;
 511
 512   data->hdc = GetDC (NULL);
 513
 514   if (unlikely (!populate_log_font (&data->log_font, font))) {
 515     DEBUG_MSG (UNISCRIBE, font, "Font populate_log_font() failed");
 516     _hb_uniscribe_shaper_font_data_destroy (data);
 517     return NULL;
 518   }
 519
 520   data->hfont = CreateFontIndirectW (&data->log_font);
 521   if (unlikely (!data->hfont)) {
 522     DEBUG_MSG (UNISCRIBE, font, "Font CreateFontIndirectW() failed");
 523     _hb_uniscribe_shaper_font_data_destroy (data);
 524      return NULL;
 525   }
 526
 527   if (!SelectObject (data->hdc, data->hfont)) {
 528     DEBUG_MSG (UNISCRIBE, font, "Font SelectObject() failed");
 529     _hb_uniscribe_shaper_font_data_destroy (data);
 530      return NULL;
 531   }
 532
 533   return data;
 534 }
 535
 536 void
 537 _hb_uniscribe_shaper_font_data_destroy (hb_uniscribe_shaper_font_data_t *data)
 538 {
 539   if (data->hdc)
 540     ReleaseDC (NULL, data->hdc);
 541   if (data->hfont)
 542     DeleteObject (data->hfont);
 543   if (data->script_cache)
 544     ScriptFreeCache (&data->script_cache);
 545   free (data);
 546 }
 547
 548 LOGFONTW *
 549 hb_uniscribe_font_get_logfontw (hb_font_t *font)
 550 {
 551   if (unlikely (!hb_uniscribe_shaper_font_data_ensure (font))) return NULL;
 552   hb_uniscribe_shaper_font_data_t *font_data =  HB_SHAPER_DATA_GET (font);
 553   return &font_data->log_font;
 554 }
 555
 556 HFONT
 557 hb_uniscribe_font_get_hfont (hb_font_t *font)
 558 {
 559   if (unlikely (!hb_uniscribe_shaper_font_data_ensure (font))) return NULL;
 560   hb_uniscribe_shaper_font_data_t *font_data =  HB_SHAPER_DATA_GET (font);
 561   return font_data->hfont;
 562 }
 563
 564
 565 /*
 566  * shaper shape_plan data
 567  */
 568
 569 struct hb_uniscribe_shaper_shape_plan_data_t {};
 570
 571 hb_uniscribe_shaper_shape_plan_data_t *
 572 _hb_uniscribe_shaper_shape_plan_data_create (hb_shape_plan_t    *shape_plan HB_UNUSED,
 573                                              const hb_feature_t *user_features HB_UNUSED,
 574                                              unsigned int        num_user_features HB_UNUSED)
 575 {
 576   return (hb_uniscribe_shaper_shape_plan_data_t *) HB_SHAPER_DATA_SUCCEEDED;
 577 }
 578
 579 void
 580 _hb_uniscribe_shaper_shape_plan_data_destroy (hb_uniscribe_shaper_shape_plan_data_t *data HB_UNUSED)
 581 {
 582 }
 583
 584
 585 /*
 586  * shaper
 587  */
 588
 589
 590 hb_bool_t
 591 _hb_uniscribe_shape (hb_shape_plan_t    *shape_plan,
 592                      hb_font_t          *font,
 593                      hb_buffer_t        *buffer,
 594                      const hb_feature_t *features,
 595                      unsigned int        num_features)
 596 {
 597   hb_face_t *face = font->face;
 598   hb_uniscribe_shaper_face_data_t *face_data = HB_SHAPER_DATA_GET (face);
 599   hb_uniscribe_shaper_font_data_t *font_data = HB_SHAPER_DATA_GET (font);
 600   hb_uniscribe_shaper_funcs_t *funcs = face_data->funcs;
 601
 602   /*
 603    * Set up features.
 604    */
 605   hb_auto_array_t<OPENTYPE_FEATURE_RECORD> feature_records;
 606   hb_auto_array_t<range_record_t> range_records;
 607   if (num_features)
 608   {
 609     /* Sort features by start/end events. */
 610     hb_auto_array_t<feature_event_t> feature_events;
 611     for (unsigned int i = 0; i < num_features; i++)
 612     {
 613       active_feature_t feature;
 614       feature.rec.tagFeature = hb_uint32_swap (features[i].tag);
 615       feature.rec.lParameter = features[i].value;
 616       feature.order = i;
 617
 618       feature_event_t *event;
 619
 620       event = feature_events.push ();
 621       if (unlikely (!event))
 622         goto fail_features;
 623       event->index = features[i].start;
 624       event->start = true;
 625       event->feature = feature;
 626
 627       event = feature_events.push ();
 628       if (unlikely (!event))
 629         goto fail_features;
 630       event->index = features[i].end;
 631       event->start = false;
 632       event->feature = feature;
 633     }
 634     feature_events.sort ();
 635     /* Add a strategic final event. */
 636     {
 637       active_feature_t feature;
 638       feature.rec.tagFeature = 0;
 639       feature.rec.lParameter = 0;
 640       feature.order = num_features + 1;
 641
 642       feature_event_t *event = feature_events.push ();
 643       if (unlikely (!event))
 644         goto fail_features;
 645       event->index = 0; /* This value does magic. */
 646       event->start = false;
 647       event->feature = feature;
 648     }
 649
 650     /* Scan events and save features for each range. */
 651     hb_auto_array_t<active_feature_t> active_features;
 652     unsigned int last_index = 0;
 653     for (unsigned int i = 0; i < feature_events.len; i++)
 654     {
 655       feature_event_t *event = &feature_events[i];
 656
 657       if (event->index != last_index)
 658       {
 659         /* Save a snapshot of active features and the range. */
 660         range_record_t *range = range_records.push ();
 661         if (unlikely (!range))
 662           goto fail_features;
 663
 664         unsigned int offset = feature_records.len;
 665
 666         active_features.sort ();
 667         for (unsigned int j = 0; j < active_features.len; j++)
 668         {
 669           if (!j || active_features[j].rec.tagFeature != feature_records[feature_records.len - 1].tagFeature)
 670           {
 671             OPENTYPE_FEATURE_RECORD *feature = feature_records.push ();
 672             if (unlikely (!feature))
 673               goto fail_features;
 674             *feature = active_features[j].rec;
 675           }
 676           else
 677           {
 678             /* Overrides value for existing feature. */
 679             feature_records[feature_records.len - 1].lParameter = active_features[j].rec.lParameter;
 680           }
 681         }
 682
 683         /* Will convert to pointer after all is ready, since feature_records.array
 684          * may move as we grow it. */
 685         range->props.potfRecords = reinterpret_cast<OPENTYPE_FEATURE_RECORD *> (offset);
 686         range->props.cotfRecords = feature_records.len - offset;
 687         range->index_first = last_index;
 688         range->index_last  = event->index - 1;
 689
 690         last_index = event->index;
 691       }
 692
 693       if (event->start) {
 694         active_feature_t *feature = active_features.push ();
 695         if (unlikely (!feature))
 696           goto fail_features;
 697         *feature = event->feature;
 698       } else {
 699         active_feature_t *feature = active_features.find (&event->feature);
 700         if (feature)
 701           active_features.remove (feature - active_features.array);
 702       }
 703     }
 704
 705     if (!range_records.len) /* No active feature found. */
 706       goto fail_features;
 707
 708     /* Fixup the pointers. */
 709     for (unsigned int i = 0; i < range_records.len; i++)
 710     {
 711       range_record_t *range = &range_records[i];
 712       range->props.potfRecords = feature_records.array + reinterpret_cast<unsigned int> (range->props.potfRecords);
 713     }
 714   }
 715   else
 716   {
 717   fail_features:
 718     num_features = 0;
 719   }
 720
 721 #define FAIL(...) \
 722   HB_STMT_START { \
 723     DEBUG_MSG (UNISCRIBE, NULL, __VA_ARGS__); \
 724     return false; \
 725   } HB_STMT_END;
 726
 727   HRESULT hr;
 728
 729 retry:
 730
 731   unsigned int scratch_size;
 732   hb_buffer_t::scratch_buffer_t *scratch = buffer->get_scratch_buffer (&scratch_size);
 733
 734 #define ALLOCATE_ARRAY(Type, name, len) \
 735   Type *name = (Type *) scratch; \
 736   { \
 737     unsigned int _consumed = DIV_CEIL ((len) * sizeof (Type), sizeof (*scratch)); \
 738     assert (_consumed <= scratch_size); \
 739     scratch += _consumed; \
 740     scratch_size -= _consumed; \
 741   }
 742
 743 #define utf16_index() var1.u32
 744
 745   ALLOCATE_ARRAY (WCHAR, pchars, buffer->len * 2);
 746
 747   unsigned int chars_len = 0;
 748   for (unsigned int i = 0; i < buffer->len; i++)
 749   {
 750     hb_codepoint_t c = buffer->info[i].codepoint;
 751     buffer->info[i].utf16_index() = chars_len;
 752     if (likely (c < 0x10000))
 753       pchars[chars_len++] = c;
 754     else if (unlikely (c >= 0x110000))
 755       pchars[chars_len++] = 0xFFFD;
 756     else {
 757       pchars[chars_len++] = 0xD800 + ((c - 0x10000) >> 10);
 758       pchars[chars_len++] = 0xDC00 + ((c - 0x10000) & ((1 << 10) - 1));
 759     }
 760   }
 761
 762   ALLOCATE_ARRAY (WORD, log_clusters, chars_len);
 763   ALLOCATE_ARRAY (SCRIPT_CHARPROP, char_props, chars_len);
 764
 765   if (num_features)
 766   {
 767     /* Need log_clusters to assign features. */
 768     chars_len = 0;
 769     for (unsigned int i = 0; i < buffer->len; i++)
 770     {
 771       hb_codepoint_t c = buffer->info[i].codepoint;
 772       unsigned int cluster = buffer->info[i].cluster;
 773       log_clusters[chars_len++] = cluster;
 774       if (c >= 0x10000 && c < 0x110000)
 775         log_clusters[chars_len++] = cluster; /* Surrogates. */
 776     }
 777   }
 778
 779   /* All the following types are sized in multiples of sizeof(int). */
 780   unsigned int glyphs_size = scratch_size / ((sizeof (WORD) +
 781                                               sizeof (SCRIPT_GLYPHPROP) +
 782                                               sizeof (int) +
 783                                               sizeof (GOFFSET) +
 784                                               sizeof (uint32_t))
 785                                              / sizeof (int));
 786
 787   ALLOCATE_ARRAY (WORD, glyphs, glyphs_size);
 788   ALLOCATE_ARRAY (SCRIPT_GLYPHPROP, glyph_props, glyphs_size);
 789   ALLOCATE_ARRAY (int, advances, glyphs_size);
 790   ALLOCATE_ARRAY (GOFFSET, offsets, glyphs_size);
 791   ALLOCATE_ARRAY (uint32_t, vis_clusters, glyphs_size);
 792
 793   /* Note:
 794    * We can't touch the contents of glyph_props.  Our fallback
 795    * implementations of Shape and Place functions use that buffer
 796    * by casting it to a different type.  It works because they
 797    * both agree about it, but if we want to access it here we
 798    * need address that issue first.
 799    */
 800
 801 #undef ALLOCATE_ARRAY
 802
 803 #define MAX_ITEMS 256
 804
 805   SCRIPT_ITEM items[MAX_ITEMS + 1];
 806   SCRIPT_CONTROL bidi_control = {0};
 807   SCRIPT_STATE bidi_state = {0};
 808   ULONG script_tags[MAX_ITEMS];
 809   int item_count;
 810
 811   /* MinGW32 doesn't define fMergeNeutralItems, so we bruteforce */
 812   //bidi_control.fMergeNeutralItems = true;
 813   *(uint32_t*)&bidi_control |= 1<<24;
 814
 815   bidi_state.uBidiLevel = HB_DIRECTION_IS_FORWARD (buffer->props.direction) ? 0 : 1;
 816   bidi_state.fOverrideDirection = 1;
 817
 818   hr = funcs->ScriptItemizeOpenType (pchars,
 819                                      chars_len,
 820                                      MAX_ITEMS,
 821                                      &bidi_control,
 822                                      &bidi_state,
 823                                      items,
 824                                      script_tags,
 825                                      &item_count);
 826   if (unlikely (FAILED (hr)))
 827     FAIL ("ScriptItemizeOpenType() failed: 0x%08xL", hr);
 828
 829 #undef MAX_ITEMS
 830
 831   OPENTYPE_TAG language_tag = hb_uint32_swap (hb_ot_tag_from_language (buffer->props.language));
 832   hb_auto_array_t<TEXTRANGE_PROPERTIES*> range_properties;
 833   hb_auto_array_t<int> range_char_counts;
 834
 835   unsigned int glyphs_offset = 0;
 836   unsigned int glyphs_len;
 837   bool backward = HB_DIRECTION_IS_BACKWARD (buffer->props.direction);
 838   for (unsigned int i = 0; i < item_count; i++)
 839   {
 840     unsigned int chars_offset = items[i].iCharPos;
 841     unsigned int item_chars_len = items[i + 1].iCharPos - chars_offset;
 842
 843     if (num_features)
 844     {
 845       range_properties.shrink (0);
 846       range_char_counts.shrink (0);
 847
 848       range_record_t *last_range = &range_records[0];
 849
 850       for (unsigned int k = chars_offset; k < chars_offset + item_chars_len; k++)
 851       {
 852         range_record_t *range = last_range;
 853         while (log_clusters[k] < range->index_first)
 854           range--;
 855         while (log_clusters[k] > range->index_last)
 856           range++;
 857         if (!range_properties.len ||
 858             &range->props != range_properties[range_properties.len - 1])
 859         {
 860           TEXTRANGE_PROPERTIES **props = range_properties.push ();
 861           int *c = range_char_counts.push ();
 862           if (unlikely (!props || !c))
 863           {
 864             range_properties.shrink (0);
 865             range_char_counts.shrink (0);
 866             break;
 867           }
 868           *props = &range->props;
 869           *c = 1;
 870         }
 871         else
 872         {
 873           range_char_counts[range_char_counts.len - 1]++;
 874         }
 875
 876         last_range = range;
 877       }
 878     }
 879
 880     /* Asking for glyphs in logical order circumvents at least
 881      * one bug in Uniscribe. */
 882     items[i].a.fLogicalOrder = true;
 883
 884   retry_shape:
 885     hr = funcs->ScriptShapeOpenType (font_data->hdc,
 886                                      &font_data->script_cache,
 887                                      &items[i].a,
 888                                      script_tags[i],
 889                                      language_tag,
 890                                      range_char_counts.array,
 891                                      range_properties.array,
 892                                      range_properties.len,
 893                                      pchars + chars_offset,
 894                                      item_chars_len,
 895                                      glyphs_size - glyphs_offset,
 896                                      /* out */
 897                                      log_clusters + chars_offset,
 898                                      char_props + chars_offset,
 899                                      glyphs + glyphs_offset,
 900                                      glyph_props + glyphs_offset,
 901                                      (int *) &glyphs_len);
 902
 903     if (unlikely (items[i].a.fNoGlyphIndex))
 904       FAIL ("ScriptShapeOpenType() set fNoGlyphIndex");
 905     if (unlikely (hr == E_OUTOFMEMORY))
 906     {
 907       buffer->ensure (buffer->allocated * 2);
 908       if (buffer->in_error)
 909         FAIL ("Buffer resize failed");
 910       goto retry;
 911     }
 912     if (unlikely (hr == USP_E_SCRIPT_NOT_IN_FONT))
 913     {
 914       if (items[i].a.eScript == SCRIPT_UNDEFINED)
 915         FAIL ("ScriptShapeOpenType() failed: Font doesn't support script");
 916       items[i].a.eScript = SCRIPT_UNDEFINED;
 917       goto retry_shape;
 918     }
 919     if (unlikely (FAILED (hr)))
 920     {
 921       FAIL ("ScriptShapeOpenType() failed: 0x%08xL", hr);
 922     }
 923
 924     for (unsigned int j = chars_offset; j < chars_offset + item_chars_len; j++)
 925       log_clusters[j] += glyphs_offset;
 926
 927     hr = funcs->ScriptPlaceOpenType (font_data->hdc,
 928                                      &font_data->script_cache,
 929                                      &items[i].a,
 930                                      script_tags[i],
 931                                      language_tag,
 932                                      range_char_counts.array,
 933                                      range_properties.array,
 934                                      range_properties.len,
 935                                      pchars + chars_offset,
 936                                      log_clusters + chars_offset,
 937                                      char_props + chars_offset,
 938                                      item_chars_len,
 939                                      glyphs + glyphs_offset,
 940                                      glyph_props + glyphs_offset,
 941                                      glyphs_len,
 942                                      /* out */
 943                                      advances + glyphs_offset,
 944                                      offsets + glyphs_offset,
 945                                      NULL);
 946     if (unlikely (FAILED (hr)))
 947       FAIL ("ScriptPlaceOpenType() failed: 0x%08xL", hr);
 948
 949     if (DEBUG_ENABLED (UNISCRIBE))
 950       fprintf (stderr, "Item %d RTL %d LayoutRTL %d LogicalOrder %d ScriptTag %c%c%c%c\n",
 951                i,
 952                items[i].a.fRTL,
 953                items[i].a.fLayoutRTL,
 954                items[i].a.fLogicalOrder,
 955                HB_UNTAG (hb_uint32_swap (script_tags[i])));
 956
 957     glyphs_offset += glyphs_len;
 958   }
 959   glyphs_len = glyphs_offset;
 960
 961   /* Ok, we've got everything we need, now compose output buffer,
 962    * very, *very*, carefully! */
 963
 964   /* Calculate visual-clusters.  That's what we ship. */
 965   for (unsigned int i = 0; i < glyphs_len; i++)
 966     vis_clusters[i] = -1;
 967   for (unsigned int i = 0; i < buffer->len; i++) {
 968     uint32_t *p = &vis_clusters[log_clusters[buffer->info[i].utf16_index()]];
 969     *p = MIN (*p, buffer->info[i].cluster);
 970   }
 971   for (unsigned int i = 1; i < glyphs_len; i++)
 972     if (vis_clusters[i] == -1)
 973       vis_clusters[i] = vis_clusters[i - 1];
 974
 975 #undef utf16_index
 976
 977   buffer->ensure (glyphs_len);
 978   if (buffer->in_error)
 979     FAIL ("Buffer in error");
 980
 981 #undef FAIL
 982
 983   /* Set glyph infos */
 984   buffer->len = 0;
 985   for (unsigned int i = 0; i < glyphs_len; i++)
 986   {
 987     hb_glyph_info_t *info = &buffer->info[buffer->len++];
 988
 989     info->codepoint = glyphs[i];
 990     info->cluster = vis_clusters[i];
 991
 992     /* The rest is crap.  Let's store position info there for now. */
 993     info->mask = advances[i];
 994     info->var1.u32 = offsets[i].du;
 995     info->var2.u32 = offsets[i].dv;
 996   }
 997
 998   /* Set glyph positions */
 999   buffer->clear_positions ();
1000   for (unsigned int i = 0; i < glyphs_len; i++)
1001   {
1002     hb_glyph_info_t *info = &buffer->info[i];
1003     hb_glyph_position_t *pos = &buffer->pos[i];
1004
1005     /* TODO vertical */
1006     pos->x_advance = info->mask;
1007     pos->x_offset = backward ? -info->var1.u32 : info->var1.u32;
1008     pos->y_offset = info->var2.u32;
1009   }
1010
1011   if (backward)
1012     hb_buffer_reverse (buffer);
1013
1014   /* Wow, done! */
1015   return true;
1016 }
1017
1018