• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  * Copyright © 2014  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 #ifndef HB_OT_CMAP_TABLE_HH
28 #define HB_OT_CMAP_TABLE_HH
29 
30 #include "hb-open-type.hh"
31 #include "hb-set.hh"
32 
33 /*
34  * cmap -- Character to Glyph Index Mapping
35  * https://docs.microsoft.com/en-us/typography/opentype/spec/cmap
36  */
37 #define HB_OT_TAG_cmap HB_TAG('c','m','a','p')
38 
39 namespace OT {
40 
41 
42 struct CmapSubtableFormat0
43 {
get_glyphOT::CmapSubtableFormat044   bool get_glyph (hb_codepoint_t codepoint, hb_codepoint_t *glyph) const
45   {
46     hb_codepoint_t gid = codepoint < 256 ? glyphIdArray[codepoint] : 0;
47     if (!gid)
48       return false;
49     *glyph = gid;
50     return true;
51   }
collect_unicodesOT::CmapSubtableFormat052   void collect_unicodes (hb_set_t *out) const
53   {
54     for (unsigned int i = 0; i < 256; i++)
55       if (glyphIdArray[i])
56 	out->add (i);
57   }
58 
sanitizeOT::CmapSubtableFormat059   bool sanitize (hb_sanitize_context_t *c) const
60   {
61     TRACE_SANITIZE (this);
62     return_trace (c->check_struct (this));
63   }
64 
65   protected:
66   HBUINT16	format;		/* Format number is set to 0. */
67   HBUINT16	length;		/* Byte length of this subtable. */
68   HBUINT16	language;	/* Ignore. */
69   HBUINT8	glyphIdArray[256];/* An array that maps character
70 				 * code to glyph index values. */
71   public:
72   DEFINE_SIZE_STATIC (6 + 256);
73 };
74 
75 struct CmapSubtableFormat4
76 {
77 
78   template<typename Iterator,
79 	   hb_requires (hb_is_iterator (Iterator))>
serialize_endcode_arrayOT::CmapSubtableFormat480   HBUINT16* serialize_endcode_array (hb_serialize_context_t *c,
81 				     Iterator it)
82   {
83     HBUINT16 *endCode = c->start_embed<HBUINT16> ();
84     hb_codepoint_t prev_endcp = 0xFFFF;
85 
86     + it
87     | hb_apply ([&] (const hb_item_type<Iterator> _)
88 		{
89 		  if (prev_endcp != 0xFFFF && prev_endcp + 1u != _.first)
90 		  {
91 		    HBUINT16 end_code;
92 		    end_code = prev_endcp;
93 		    c->copy<HBUINT16> (end_code);
94 		  }
95 		  prev_endcp = _.first;
96 		})
97     ;
98 
99     {
100       // last endCode
101       HBUINT16 endcode;
102       endcode = prev_endcp;
103       if (unlikely (!c->copy<HBUINT16> (endcode))) return nullptr;
104       // There must be a final entry with end_code == 0xFFFF.
105       if (prev_endcp != 0xFFFF)
106       {
107 	HBUINT16 finalcode;
108 	finalcode = 0xFFFF;
109 	if (unlikely (!c->copy<HBUINT16> (finalcode))) return nullptr;
110       }
111     }
112 
113     return endCode;
114   }
115 
116   template<typename Iterator,
117 	   hb_requires (hb_is_iterator (Iterator))>
serialize_startcode_arrayOT::CmapSubtableFormat4118   HBUINT16* serialize_startcode_array (hb_serialize_context_t *c,
119 				       Iterator it)
120   {
121     HBUINT16 *startCode = c->start_embed<HBUINT16> ();
122     hb_codepoint_t prev_cp = 0xFFFF;
123 
124     + it
125     | hb_apply ([&] (const hb_item_type<Iterator> _)
126 		{
127 		  if (prev_cp == 0xFFFF || prev_cp + 1u != _.first)
128 		  {
129 		    HBUINT16 start_code;
130 		    start_code = _.first;
131 		    c->copy<HBUINT16> (start_code);
132 		  }
133 
134 		  prev_cp = _.first;
135 		})
136     ;
137 
138     // There must be a final entry with end_code == 0xFFFF.
139     if (it.len () == 0 || prev_cp != 0xFFFF)
140     {
141       HBUINT16 finalcode;
142       finalcode = 0xFFFF;
143       if (unlikely (!c->copy<HBUINT16> (finalcode))) return nullptr;
144     }
145 
146     return startCode;
147   }
148 
149   template<typename Iterator,
150 	   hb_requires (hb_is_iterator (Iterator))>
serialize_idDelta_arrayOT::CmapSubtableFormat4151   HBINT16* serialize_idDelta_array (hb_serialize_context_t *c,
152 				     Iterator it,
153 				     HBUINT16 *endCode,
154 				     HBUINT16 *startCode,
155 				     unsigned segcount)
156   {
157     unsigned i = 0;
158     hb_codepoint_t last_gid = 0, start_gid = 0, last_cp = 0xFFFF;
159     bool use_delta = true;
160 
161     HBINT16 *idDelta = c->start_embed<HBINT16> ();
162     if ((char *)idDelta - (char *)startCode != (int) segcount * (int) HBINT16::static_size)
163       return nullptr;
164 
165     + it
166     | hb_apply ([&] (const hb_item_type<Iterator> _)
167 		{
168 		  if (_.first == startCode[i])
169 		  {
170 		    use_delta = true;
171 		    start_gid = _.second;
172 		  }
173 		  else if (_.second != last_gid + 1) use_delta = false;
174 
175 		  if (_.first == endCode[i])
176 		  {
177 		    HBINT16 delta;
178 		    if (use_delta) delta = (int)start_gid - (int)startCode[i];
179 		    else delta = 0;
180 		    c->copy<HBINT16> (delta);
181 
182 		    i++;
183 		  }
184 
185 		  last_gid = _.second;
186 		  last_cp = _.first;
187 		})
188     ;
189 
190     if (it.len () == 0 || last_cp != 0xFFFF)
191     {
192       HBINT16 delta;
193       delta = 1;
194       if (unlikely (!c->copy<HBINT16> (delta))) return nullptr;
195     }
196 
197     return idDelta;
198   }
199 
200   template<typename Iterator,
201 	   hb_requires (hb_is_iterator (Iterator))>
serialize_rangeoffset_glyidOT::CmapSubtableFormat4202   HBUINT16* serialize_rangeoffset_glyid (hb_serialize_context_t *c,
203 					 Iterator it,
204 					 HBUINT16 *endCode,
205 					 HBUINT16 *startCode,
206 					 HBINT16 *idDelta,
207 					 unsigned segcount)
208   {
209     HBUINT16 *idRangeOffset = c->allocate_size<HBUINT16> (HBUINT16::static_size * segcount);
210     if (unlikely (!c->check_success (idRangeOffset))) return nullptr;
211     if (unlikely ((char *)idRangeOffset - (char *)idDelta != (int) segcount * (int) HBINT16::static_size)) return nullptr;
212 
213     + hb_range (segcount)
214     | hb_filter ([&] (const unsigned _) { return idDelta[_] == 0; })
215     | hb_apply ([&] (const unsigned i)
216 		{
217 		  idRangeOffset[i] = 2 * (c->start_embed<HBUINT16> () - idRangeOffset - i);
218 
219 		  + it
220 		  | hb_filter ([&] (const hb_item_type<Iterator> _) { return _.first >= startCode[i] && _.first <= endCode[i]; })
221 		  | hb_apply ([&] (const hb_item_type<Iterator> _)
222 			      {
223 				HBUINT16 glyID;
224 				glyID = _.second;
225 				c->copy<HBUINT16> (glyID);
226 			      })
227 		  ;
228 
229 
230 		})
231     ;
232 
233     return idRangeOffset;
234   }
235 
236   template<typename Iterator,
237 	   hb_requires (hb_is_iterator (Iterator))>
serializeOT::CmapSubtableFormat4238   void serialize (hb_serialize_context_t *c,
239 		  Iterator it)
240   {
241     unsigned table_initpos = c->length ();
242     if (unlikely (!c->extend_min (*this))) return;
243     this->format = 4;
244 
245     //serialize endCode[]
246     HBUINT16 *endCode = serialize_endcode_array (c, it);
247     if (unlikely (!endCode)) return;
248 
249     unsigned segcount = (c->length () - min_size) / HBUINT16::static_size;
250 
251     // 2 bytes of padding.
252     if (unlikely (!c->allocate_size<HBUINT16> (HBUINT16::static_size))) return; // 2 bytes of padding.
253 
254    // serialize startCode[]
255     HBUINT16 *startCode = serialize_startcode_array (c, it);
256     if (unlikely (!startCode)) return;
257 
258     //serialize idDelta[]
259     HBINT16 *idDelta = serialize_idDelta_array (c, it, endCode, startCode, segcount);
260     if (unlikely (!idDelta)) return;
261 
262     HBUINT16 *idRangeOffset = serialize_rangeoffset_glyid (c, it, endCode, startCode, idDelta, segcount);
263     if (unlikely (!c->check_success (idRangeOffset))) return;
264 
265     if (unlikely (!c->check_assign(this->length, c->length () - table_initpos))) return;
266     this->segCountX2 = segcount * 2;
267     this->entrySelector = hb_max (1u, hb_bit_storage (segcount)) - 1;
268     this->searchRange = 2 * (1u << this->entrySelector);
269     this->rangeShift = segcount * 2 > this->searchRange
270 		       ? 2 * segcount - this->searchRange
271 		       : 0;
272   }
273 
274   struct accelerator_t
275   {
accelerator_tOT::CmapSubtableFormat4::accelerator_t276     accelerator_t () {}
accelerator_tOT::CmapSubtableFormat4::accelerator_t277     accelerator_t (const CmapSubtableFormat4 *subtable) { init (subtable); }
~accelerator_tOT::CmapSubtableFormat4::accelerator_t278     ~accelerator_t () { fini (); }
279 
initOT::CmapSubtableFormat4::accelerator_t280     void init (const CmapSubtableFormat4 *subtable)
281     {
282       segCount = subtable->segCountX2 / 2;
283       endCount = subtable->values.arrayZ;
284       startCount = endCount + segCount + 1;
285       idDelta = startCount + segCount;
286       idRangeOffset = idDelta + segCount;
287       glyphIdArray = idRangeOffset + segCount;
288       glyphIdArrayLength = (subtable->length - 16 - 8 * segCount) / 2;
289     }
finiOT::CmapSubtableFormat4::accelerator_t290     void fini () {}
291 
get_glyphOT::CmapSubtableFormat4::accelerator_t292     bool get_glyph (hb_codepoint_t codepoint, hb_codepoint_t *glyph) const
293     {
294       /* Custom two-array bsearch. */
295       int min = 0, max = (int) this->segCount - 1;
296       const HBUINT16 *startCount = this->startCount;
297       const HBUINT16 *endCount = this->endCount;
298       unsigned int i;
299       while (min <= max)
300       {
301 	int mid = ((unsigned int) min + (unsigned int) max) / 2;
302 	if (codepoint < startCount[mid])
303 	  max = mid - 1;
304 	else if (codepoint > endCount[mid])
305 	  min = mid + 1;
306 	else
307 	{
308 	  i = mid;
309 	  goto found;
310 	}
311       }
312       return false;
313 
314     found:
315       hb_codepoint_t gid;
316       unsigned int rangeOffset = this->idRangeOffset[i];
317       if (rangeOffset == 0)
318 	gid = codepoint + this->idDelta[i];
319       else
320       {
321 	/* Somebody has been smoking... */
322 	unsigned int index = rangeOffset / 2 + (codepoint - this->startCount[i]) + i - this->segCount;
323 	if (unlikely (index >= this->glyphIdArrayLength))
324 	  return false;
325 	gid = this->glyphIdArray[index];
326 	if (unlikely (!gid))
327 	  return false;
328 	gid += this->idDelta[i];
329       }
330       gid &= 0xFFFFu;
331       if (!gid)
332 	return false;
333       *glyph = gid;
334       return true;
335     }
get_glyph_funcOT::CmapSubtableFormat4::accelerator_t336     HB_INTERNAL static bool get_glyph_func (const void *obj, hb_codepoint_t codepoint, hb_codepoint_t *glyph)
337     { return ((const accelerator_t *) obj)->get_glyph (codepoint, glyph); }
collect_unicodesOT::CmapSubtableFormat4::accelerator_t338     void collect_unicodes (hb_set_t *out) const
339     {
340       unsigned int count = this->segCount;
341       if (count && this->startCount[count - 1] == 0xFFFFu)
342 	count--; /* Skip sentinel segment. */
343       for (unsigned int i = 0; i < count; i++)
344       {
345 	hb_codepoint_t start = this->startCount[i];
346 	hb_codepoint_t end = this->endCount[i];
347 	unsigned int rangeOffset = this->idRangeOffset[i];
348 	if (rangeOffset == 0)
349 	{
350 	  for (hb_codepoint_t codepoint = start; codepoint <= end; codepoint++)
351 	  {
352 	    hb_codepoint_t gid = (codepoint + this->idDelta[i]) & 0xFFFFu;
353 	    if (unlikely (!gid))
354 	      continue;
355 	    out->add (codepoint);
356 	  }
357 	}
358 	else
359 	{
360 	  for (hb_codepoint_t codepoint = start; codepoint <= end; codepoint++)
361 	  {
362 	    unsigned int index = rangeOffset / 2 + (codepoint - this->startCount[i]) + i - this->segCount;
363 	    if (unlikely (index >= this->glyphIdArrayLength))
364 	      break;
365 	    hb_codepoint_t gid = this->glyphIdArray[index];
366 	    if (unlikely (!gid))
367 	      continue;
368 	    out->add (codepoint);
369 	  }
370 	}
371       }
372     }
373 
374     const HBUINT16 *endCount;
375     const HBUINT16 *startCount;
376     const HBUINT16 *idDelta;
377     const HBUINT16 *idRangeOffset;
378     const HBUINT16 *glyphIdArray;
379     unsigned int segCount;
380     unsigned int glyphIdArrayLength;
381   };
382 
get_glyphOT::CmapSubtableFormat4383   bool get_glyph (hb_codepoint_t codepoint, hb_codepoint_t *glyph) const
384   {
385     accelerator_t accel (this);
386     return accel.get_glyph_func (&accel, codepoint, glyph);
387   }
collect_unicodesOT::CmapSubtableFormat4388   void collect_unicodes (hb_set_t *out) const
389   {
390     accelerator_t accel (this);
391     accel.collect_unicodes (out);
392   }
393 
sanitizeOT::CmapSubtableFormat4394   bool sanitize (hb_sanitize_context_t *c) const
395   {
396     TRACE_SANITIZE (this);
397     if (unlikely (!c->check_struct (this)))
398       return_trace (false);
399 
400     if (unlikely (!c->check_range (this, length)))
401     {
402       /* Some broken fonts have too long of a "length" value.
403        * If that is the case, just change the value to truncate
404        * the subtable at the end of the blob. */
405       uint16_t new_length = (uint16_t) hb_min ((uintptr_t) 65535,
406 					    (uintptr_t) (c->end -
407 							 (char *) this));
408       if (!c->try_set (&length, new_length))
409 	return_trace (false);
410     }
411 
412     return_trace (16 + 4 * (unsigned int) segCountX2 <= length);
413   }
414 
415 
416 
417   protected:
418   HBUINT16	format;		/* Format number is set to 4. */
419   HBUINT16	length;		/* This is the length in bytes of the
420 				 * subtable. */
421   HBUINT16	language;	/* Ignore. */
422   HBUINT16	segCountX2;	/* 2 x segCount. */
423   HBUINT16	searchRange;	/* 2 * (2**floor(log2(segCount))) */
424   HBUINT16	entrySelector;	/* log2(searchRange/2) */
425   HBUINT16	rangeShift;	/* 2 x segCount - searchRange */
426 
427   UnsizedArrayOf<HBUINT16>
428 		values;
429 #if 0
430   HBUINT16	endCount[segCount];	/* End characterCode for each segment,
431 					 * last=0xFFFFu. */
432   HBUINT16	reservedPad;		/* Set to 0. */
433   HBUINT16	startCount[segCount];	/* Start character code for each segment. */
434   HBINT16		idDelta[segCount];	/* Delta for all character codes in segment. */
435   HBUINT16	idRangeOffset[segCount];/* Offsets into glyphIdArray or 0 */
436   UnsizedArrayOf<HBUINT16>
437 		glyphIdArray;	/* Glyph index array (arbitrary length) */
438 #endif
439 
440   public:
441   DEFINE_SIZE_ARRAY (14, values);
442 };
443 
444 struct CmapSubtableLongGroup
445 {
446   friend struct CmapSubtableFormat12;
447   friend struct CmapSubtableFormat13;
448   template<typename U>
449   friend struct CmapSubtableLongSegmented;
450   friend struct cmap;
451 
cmpOT::CmapSubtableLongGroup452   int cmp (hb_codepoint_t codepoint) const
453   {
454     if (codepoint < startCharCode) return -1;
455     if (codepoint > endCharCode)   return +1;
456     return 0;
457   }
458 
sanitizeOT::CmapSubtableLongGroup459   bool sanitize (hb_sanitize_context_t *c) const
460   {
461     TRACE_SANITIZE (this);
462     return_trace (c->check_struct (this));
463   }
464 
465   private:
466   HBUINT32		startCharCode;	/* First character code in this group. */
467   HBUINT32		endCharCode;	/* Last character code in this group. */
468   HBUINT32		glyphID;	/* Glyph index; interpretation depends on
469 					 * subtable format. */
470   public:
471   DEFINE_SIZE_STATIC (12);
472 };
473 DECLARE_NULL_NAMESPACE_BYTES (OT, CmapSubtableLongGroup);
474 
475 template <typename UINT>
476 struct CmapSubtableTrimmed
477 {
get_glyphOT::CmapSubtableTrimmed478   bool get_glyph (hb_codepoint_t codepoint, hb_codepoint_t *glyph) const
479   {
480     /* Rely on our implicit array bound-checking. */
481     hb_codepoint_t gid = glyphIdArray[codepoint - startCharCode];
482     if (!gid)
483       return false;
484     *glyph = gid;
485     return true;
486   }
collect_unicodesOT::CmapSubtableTrimmed487   void collect_unicodes (hb_set_t *out) const
488   {
489     hb_codepoint_t start = startCharCode;
490     unsigned int count = glyphIdArray.len;
491     for (unsigned int i = 0; i < count; i++)
492       if (glyphIdArray[i])
493 	out->add (start + i);
494   }
495 
sanitizeOT::CmapSubtableTrimmed496   bool sanitize (hb_sanitize_context_t *c) const
497   {
498     TRACE_SANITIZE (this);
499     return_trace (c->check_struct (this) && glyphIdArray.sanitize (c));
500   }
501 
502   protected:
503   UINT		formatReserved;	/* Subtable format and (maybe) padding. */
504   UINT		length;		/* Byte length of this subtable. */
505   UINT		language;	/* Ignore. */
506   UINT		startCharCode;	/* First character code covered. */
507   ArrayOf<HBGlyphID, UINT>
508 		glyphIdArray;	/* Array of glyph index values for character
509 				 * codes in the range. */
510   public:
511   DEFINE_SIZE_ARRAY (5 * sizeof (UINT), glyphIdArray);
512 };
513 
514 struct CmapSubtableFormat6  : CmapSubtableTrimmed<HBUINT16> {};
515 struct CmapSubtableFormat10 : CmapSubtableTrimmed<HBUINT32 > {};
516 
517 template <typename T>
518 struct CmapSubtableLongSegmented
519 {
520   friend struct cmap;
521 
get_glyphOT::CmapSubtableLongSegmented522   bool get_glyph (hb_codepoint_t codepoint, hb_codepoint_t *glyph) const
523   {
524     hb_codepoint_t gid = T::group_get_glyph (groups.bsearch (codepoint), codepoint);
525     if (!gid)
526       return false;
527     *glyph = gid;
528     return true;
529   }
530 
collect_unicodesOT::CmapSubtableLongSegmented531   void collect_unicodes (hb_set_t *out) const
532   {
533     for (unsigned int i = 0; i < this->groups.len; i++)
534     {
535       hb_codepoint_t start = this->groups[i].startCharCode;
536       hb_codepoint_t end = hb_min ((hb_codepoint_t) this->groups[i].endCharCode,
537 				   (hb_codepoint_t) HB_UNICODE_MAX);
538       for (hb_codepoint_t codepoint = start; codepoint <= end; codepoint++)
539       {
540 	hb_codepoint_t gid = T::group_get_glyph (this->groups[i], codepoint);
541 	if (unlikely (!gid))
542 	  continue;
543 	out->add (codepoint);
544       }
545     }
546   }
547 
sanitizeOT::CmapSubtableLongSegmented548   bool sanitize (hb_sanitize_context_t *c) const
549   {
550     TRACE_SANITIZE (this);
551     return_trace (c->check_struct (this) && groups.sanitize (c));
552   }
553 
554   protected:
555   HBUINT16	format;		/* Subtable format; set to 12. */
556   HBUINT16	reserved;	/* Reserved; set to 0. */
557   HBUINT32	length;		/* Byte length of this subtable. */
558   HBUINT32	language;	/* Ignore. */
559   SortedArrayOf<CmapSubtableLongGroup, HBUINT32>
560 		groups;		/* Groupings. */
561   public:
562   DEFINE_SIZE_ARRAY (16, groups);
563 };
564 
565 struct CmapSubtableFormat12 : CmapSubtableLongSegmented<CmapSubtableFormat12>
566 {
group_get_glyphOT::CmapSubtableFormat12567   static hb_codepoint_t group_get_glyph (const CmapSubtableLongGroup &group,
568 					 hb_codepoint_t u)
569   { return likely (group.startCharCode <= group.endCharCode) ?
570 	   group.glyphID + (u - group.startCharCode) : 0; }
571 
572 
573   template<typename Iterator,
574 	   hb_requires (hb_is_iterator (Iterator))>
serializeOT::CmapSubtableFormat12575   void serialize (hb_serialize_context_t *c,
576 		  Iterator it)
577   {
578     if (it.len () == 0) return;
579     unsigned table_initpos = c->length ();
580     if (unlikely (!c->extend_min (*this))) return;
581 
582     hb_codepoint_t startCharCode = 0xFFFF, endCharCode = 0xFFFF;
583     hb_codepoint_t glyphID = 0;
584 
585     + it
586     | hb_apply ([&] (const hb_item_type<Iterator> _)
587 	      {
588 		if (startCharCode == 0xFFFF)
589 		{
590 		  startCharCode = _.first;
591 		  endCharCode = _.first;
592 		  glyphID = _.second;
593 		}
594 		else if (!_is_gid_consecutive (endCharCode, startCharCode, glyphID, _.first, _.second))
595 		{
596 		  CmapSubtableLongGroup  grouprecord;
597 		  grouprecord.startCharCode = startCharCode;
598 		  grouprecord.endCharCode = endCharCode;
599 		  grouprecord.glyphID = glyphID;
600 		  c->copy<CmapSubtableLongGroup> (grouprecord);
601 
602 		  startCharCode = _.first;
603 		  endCharCode = _.first;
604 		  glyphID = _.second;
605 		}
606 		else
607 		{
608 		  endCharCode = _.first;
609 		}
610 	      })
611     ;
612 
613     CmapSubtableLongGroup record;
614     record.startCharCode = startCharCode;
615     record.endCharCode = endCharCode;
616     record.glyphID = glyphID;
617     c->copy<CmapSubtableLongGroup> (record);
618 
619     this->format = 12;
620     this->reserved = 0;
621     this->length = c->length () - table_initpos;
622     this->groups.len = (this->length - min_size)/CmapSubtableLongGroup::static_size;
623   }
624 
get_sub_table_sizeOT::CmapSubtableFormat12625   static size_t get_sub_table_size (const hb_sorted_vector_t<CmapSubtableLongGroup> &groups_data)
626   { return 16 + 12 * groups_data.length; }
627 
628   private:
_is_gid_consecutiveOT::CmapSubtableFormat12629   static bool _is_gid_consecutive (hb_codepoint_t endCharCode,
630 				   hb_codepoint_t startCharCode,
631 				   hb_codepoint_t glyphID,
632 				   hb_codepoint_t cp,
633 				   hb_codepoint_t new_gid)
634   {
635     return (cp - 1 == endCharCode) &&
636 	new_gid == glyphID + (cp - startCharCode);
637   }
638 
639 };
640 
641 struct CmapSubtableFormat13 : CmapSubtableLongSegmented<CmapSubtableFormat13>
642 {
group_get_glyphOT::CmapSubtableFormat13643   static hb_codepoint_t group_get_glyph (const CmapSubtableLongGroup &group,
644 					 hb_codepoint_t u HB_UNUSED)
645   { return group.glyphID; }
646 };
647 
648 typedef enum
649 {
650   GLYPH_VARIANT_NOT_FOUND = 0,
651   GLYPH_VARIANT_FOUND = 1,
652   GLYPH_VARIANT_USE_DEFAULT = 2
653 } glyph_variant_t;
654 
655 struct UnicodeValueRange
656 {
cmpOT::UnicodeValueRange657   int cmp (const hb_codepoint_t &codepoint) const
658   {
659     if (codepoint < startUnicodeValue) return -1;
660     if (codepoint > startUnicodeValue + additionalCount) return +1;
661     return 0;
662   }
663 
sanitizeOT::UnicodeValueRange664   bool sanitize (hb_sanitize_context_t *c) const
665   {
666     TRACE_SANITIZE (this);
667     return_trace (c->check_struct (this));
668   }
669 
670   HBUINT24	startUnicodeValue;	/* First value in this range. */
671   HBUINT8	additionalCount;	/* Number of additional values in this
672 					 * range. */
673   public:
674   DEFINE_SIZE_STATIC (4);
675 };
676 
677 struct DefaultUVS : SortedArrayOf<UnicodeValueRange, HBUINT32>
678 {
collect_unicodesOT::DefaultUVS679   void collect_unicodes (hb_set_t *out) const
680   {
681     unsigned int count = len;
682     for (unsigned int i = 0; i < count; i++)
683     {
684       hb_codepoint_t first = arrayZ[i].startUnicodeValue;
685       hb_codepoint_t last = hb_min ((hb_codepoint_t) (first + arrayZ[i].additionalCount),
686 				 (hb_codepoint_t) HB_UNICODE_MAX);
687       out->add_range (first, last);
688     }
689   }
690 
copyOT::DefaultUVS691   DefaultUVS* copy (hb_serialize_context_t *c,
692 		    const hb_set_t *unicodes) const
693   {
694     DefaultUVS *out = c->start_embed<DefaultUVS> ();
695     if (unlikely (!out)) return nullptr;
696     auto snap = c->snapshot ();
697 
698     HBUINT32 len;
699     len = 0;
700     if (unlikely (!c->copy<HBUINT32> (len))) return nullptr;
701     unsigned init_len = c->length ();
702 
703     hb_codepoint_t lastCode = HB_MAP_VALUE_INVALID;
704     int count = -1;
705 
706     for (const UnicodeValueRange& _ : as_array ())
707     {
708       for (const unsigned addcnt : hb_range ((unsigned) _.additionalCount + 1))
709       {
710 	unsigned curEntry = (unsigned) _.startUnicodeValue + addcnt;
711 	if (!unicodes->has (curEntry)) continue;
712 	count += 1;
713 	if (lastCode == HB_MAP_VALUE_INVALID)
714 	  lastCode = curEntry;
715 	else if (lastCode + count != curEntry)
716 	{
717 	  UnicodeValueRange rec;
718 	  rec.startUnicodeValue = lastCode;
719 	  rec.additionalCount = count - 1;
720 	  c->copy<UnicodeValueRange> (rec);
721 
722 	  lastCode = curEntry;
723 	  count = 0;
724 	}
725       }
726     }
727 
728     if (lastCode != HB_MAP_VALUE_INVALID)
729     {
730       UnicodeValueRange rec;
731       rec.startUnicodeValue = lastCode;
732       rec.additionalCount = count;
733       c->copy<UnicodeValueRange> (rec);
734     }
735 
736     if (c->length () - init_len == 0)
737     {
738       c->revert (snap);
739       return nullptr;
740     }
741     else
742     {
743       if (unlikely (!c->check_assign (out->len, (c->length () - init_len) / UnicodeValueRange::static_size))) return nullptr;
744       return out;
745     }
746   }
747 
748   public:
749   DEFINE_SIZE_ARRAY (4, *this);
750 };
751 
752 struct UVSMapping
753 {
cmpOT::UVSMapping754   int cmp (const hb_codepoint_t &codepoint) const
755   { return unicodeValue.cmp (codepoint); }
756 
sanitizeOT::UVSMapping757   bool sanitize (hb_sanitize_context_t *c) const
758   {
759     TRACE_SANITIZE (this);
760     return_trace (c->check_struct (this));
761   }
762 
763   HBUINT24	unicodeValue;	/* Base Unicode value of the UVS */
764   HBGlyphID	glyphID;	/* Glyph ID of the UVS */
765   public:
766   DEFINE_SIZE_STATIC (5);
767 };
768 
769 struct NonDefaultUVS : SortedArrayOf<UVSMapping, HBUINT32>
770 {
collect_unicodesOT::NonDefaultUVS771   void collect_unicodes (hb_set_t *out) const
772   {
773     unsigned int count = len;
774     for (unsigned int i = 0; i < count; i++)
775       out->add (arrayZ[i].glyphID);
776   }
777 
closure_glyphsOT::NonDefaultUVS778   void closure_glyphs (const hb_set_t      *unicodes,
779 		       hb_set_t            *glyphset) const
780   {
781     + as_array ()
782     | hb_filter (unicodes, &UVSMapping::unicodeValue)
783     | hb_map (&UVSMapping::glyphID)
784     | hb_sink (glyphset)
785     ;
786   }
787 
copyOT::NonDefaultUVS788   NonDefaultUVS* copy (hb_serialize_context_t *c,
789 		       const hb_set_t *unicodes,
790 		       const hb_set_t *glyphs,
791 		       const hb_map_t *glyph_map) const
792   {
793     NonDefaultUVS *out = c->start_embed<NonDefaultUVS> ();
794     if (unlikely (!out)) return nullptr;
795 
796     auto it =
797     + as_array ()
798     | hb_filter ([&] (const UVSMapping& _)
799 		 {
800 		   return unicodes->has (_.unicodeValue) || glyphs->has (_.glyphID);
801 		 })
802     ;
803 
804     if (!it) return nullptr;
805 
806     HBUINT32 len;
807     len = it.len ();
808     if (unlikely (!c->copy<HBUINT32> (len))) return nullptr;
809 
810     for (const UVSMapping& _ : it)
811     {
812       UVSMapping mapping;
813       mapping.unicodeValue = _.unicodeValue;
814       mapping.glyphID = glyph_map->get (_.glyphID);
815       c->copy<UVSMapping> (mapping);
816     }
817 
818     return out;
819   }
820 
821   public:
822   DEFINE_SIZE_ARRAY (4, *this);
823 };
824 
825 struct VariationSelectorRecord
826 {
get_glyphOT::VariationSelectorRecord827   glyph_variant_t get_glyph (hb_codepoint_t codepoint,
828 			     hb_codepoint_t *glyph,
829 			     const void *base) const
830   {
831     if ((base+defaultUVS).bfind (codepoint))
832       return GLYPH_VARIANT_USE_DEFAULT;
833     const UVSMapping &nonDefault = (base+nonDefaultUVS).bsearch (codepoint);
834     if (nonDefault.glyphID)
835     {
836       *glyph = nonDefault.glyphID;
837        return GLYPH_VARIANT_FOUND;
838     }
839     return GLYPH_VARIANT_NOT_FOUND;
840   }
841 
collect_unicodesOT::VariationSelectorRecord842   void collect_unicodes (hb_set_t *out, const void *base) const
843   {
844     (base+defaultUVS).collect_unicodes (out);
845     (base+nonDefaultUVS).collect_unicodes (out);
846   }
847 
cmpOT::VariationSelectorRecord848   int cmp (const hb_codepoint_t &variation_selector) const
849   { return varSelector.cmp (variation_selector); }
850 
sanitizeOT::VariationSelectorRecord851   bool sanitize (hb_sanitize_context_t *c, const void *base) const
852   {
853     TRACE_SANITIZE (this);
854     return_trace (c->check_struct (this) &&
855 		  defaultUVS.sanitize (c, base) &&
856 		  nonDefaultUVS.sanitize (c, base));
857   }
858 
copyOT::VariationSelectorRecord859   VariationSelectorRecord* copy (hb_serialize_context_t *c,
860 				 const hb_set_t *unicodes,
861 				 const hb_set_t *glyphs,
862 				 const hb_map_t *glyph_map,
863 				 const void *src_base,
864 				 const void *dst_base) const
865   {
866     auto snap = c->snapshot ();
867     auto *out = c->embed<VariationSelectorRecord> (*this);
868     if (unlikely (!out)) return nullptr;
869 
870     out->defaultUVS = 0;
871     out->nonDefaultUVS = 0;
872 
873     bool drop = true;
874 
875     if (defaultUVS != 0)
876     {
877       c->push ();
878       if (c->copy (src_base+defaultUVS, unicodes))
879       {
880 	c->add_link (out->defaultUVS, c->pop_pack (), dst_base);
881 	drop = false;
882       }
883       else c->pop_discard ();
884     }
885 
886     if (nonDefaultUVS != 0)
887     {
888       c->push ();
889       if (c->copy (src_base+nonDefaultUVS, unicodes, glyphs, glyph_map))
890       {
891 	c->add_link (out->nonDefaultUVS, c->pop_pack (), dst_base);
892 	drop = false;
893       }
894       else c->pop_discard ();
895     }
896 
897     if (drop)
898     {
899       c->revert (snap);
900       return nullptr;
901     }
902     else return out;
903   }
904 
905   HBUINT24	varSelector;	/* Variation selector. */
906   LOffsetTo<DefaultUVS>
907 		defaultUVS;	/* Offset to Default UVS Table.  May be 0. */
908   LOffsetTo<NonDefaultUVS>
909 		nonDefaultUVS;	/* Offset to Non-Default UVS Table.  May be 0. */
910   public:
911   DEFINE_SIZE_STATIC (11);
912 };
913 
914 struct CmapSubtableFormat14
915 {
get_glyph_variantOT::CmapSubtableFormat14916   glyph_variant_t get_glyph_variant (hb_codepoint_t codepoint,
917 				     hb_codepoint_t variation_selector,
918 				     hb_codepoint_t *glyph) const
919   { return record.bsearch (variation_selector).get_glyph (codepoint, glyph, this); }
920 
collect_variation_selectorsOT::CmapSubtableFormat14921   void collect_variation_selectors (hb_set_t *out) const
922   {
923     unsigned int count = record.len;
924     for (unsigned int i = 0; i < count; i++)
925       out->add (record.arrayZ[i].varSelector);
926   }
collect_variation_unicodesOT::CmapSubtableFormat14927   void collect_variation_unicodes (hb_codepoint_t variation_selector,
928 				   hb_set_t *out) const
929   { record.bsearch (variation_selector).collect_unicodes (out, this); }
930 
serializeOT::CmapSubtableFormat14931   void serialize (hb_serialize_context_t *c,
932 		  const hb_set_t *unicodes,
933 		  const hb_set_t *glyphs,
934 		  const hb_map_t *glyph_map,
935 		  const void *src_base)
936   {
937     auto snap = c->snapshot ();
938     unsigned table_initpos = c->length ();
939     const char* init_tail = c->tail;
940 
941     if (unlikely (!c->extend_min (*this))) return;
942     this->format = 14;
943 
944     const CmapSubtableFormat14 *src_tbl = reinterpret_cast<const CmapSubtableFormat14*> (src_base);
945     for (const VariationSelectorRecord& _ : src_tbl->record)
946       c->copy (_, unicodes, glyphs, glyph_map, src_base, this);
947 
948     if (c->length () - table_initpos == CmapSubtableFormat14::min_size)
949       c->revert (snap);
950     else
951     {
952       int tail_len = init_tail - c->tail;
953       c->check_assign (this->length, c->length () - table_initpos + tail_len);
954       c->check_assign (this->record.len, (c->length () - table_initpos - CmapSubtableFormat14::min_size) / VariationSelectorRecord::static_size);
955     }
956   }
957 
closure_glyphsOT::CmapSubtableFormat14958   void closure_glyphs (const hb_set_t      *unicodes,
959 		       hb_set_t            *glyphset) const
960   {
961     + hb_iter (record)
962     | hb_filter (hb_bool, &VariationSelectorRecord::nonDefaultUVS)
963     | hb_map (&VariationSelectorRecord::nonDefaultUVS)
964     | hb_map (hb_add (this))
965     | hb_apply ([=] (const NonDefaultUVS& _) { _.closure_glyphs (unicodes, glyphset); })
966     ;
967   }
968 
sanitizeOT::CmapSubtableFormat14969   bool sanitize (hb_sanitize_context_t *c) const
970   {
971     TRACE_SANITIZE (this);
972     return_trace (c->check_struct (this) &&
973 		  record.sanitize (c, this));
974   }
975 
976   protected:
977   HBUINT16	format;		/* Format number is set to 14. */
978   HBUINT32	length;		/* Byte length of this subtable. */
979   SortedArrayOf<VariationSelectorRecord, HBUINT32>
980 		record;		/* Variation selector records; sorted
981 				 * in increasing order of `varSelector'. */
982   public:
983   DEFINE_SIZE_ARRAY (10, record);
984 };
985 
986 struct CmapSubtable
987 {
988   /* Note: We intentionally do NOT implement subtable formats 2 and 8. */
989 
get_glyphOT::CmapSubtable990   bool get_glyph (hb_codepoint_t codepoint,
991 		  hb_codepoint_t *glyph) const
992   {
993     switch (u.format) {
994     case  0: return u.format0 .get_glyph (codepoint, glyph);
995     case  4: return u.format4 .get_glyph (codepoint, glyph);
996     case  6: return u.format6 .get_glyph (codepoint, glyph);
997     case 10: return u.format10.get_glyph (codepoint, glyph);
998     case 12: return u.format12.get_glyph (codepoint, glyph);
999     case 13: return u.format13.get_glyph (codepoint, glyph);
1000     case 14:
1001     default: return false;
1002     }
1003   }
collect_unicodesOT::CmapSubtable1004   void collect_unicodes (hb_set_t *out) const
1005   {
1006     switch (u.format) {
1007     case  0: u.format0 .collect_unicodes (out); return;
1008     case  4: u.format4 .collect_unicodes (out); return;
1009     case  6: u.format6 .collect_unicodes (out); return;
1010     case 10: u.format10.collect_unicodes (out); return;
1011     case 12: u.format12.collect_unicodes (out); return;
1012     case 13: u.format13.collect_unicodes (out); return;
1013     case 14:
1014     default: return;
1015     }
1016   }
1017 
1018   template<typename Iterator,
1019 	   hb_requires (hb_is_iterator (Iterator))>
serializeOT::CmapSubtable1020   void serialize (hb_serialize_context_t *c,
1021 		  Iterator it,
1022 		  unsigned format,
1023 		  const hb_subset_plan_t *plan,
1024 		  const void *src_base)
1025   {
1026     switch (format) {
1027     case  4: u.format4.serialize (c, it);  return;
1028     case 12: u.format12.serialize (c, it); return;
1029     case 14: u.format14.serialize (c, plan->unicodes, plan->_glyphset, plan->glyph_map, src_base); return;
1030     default: return;
1031     }
1032   }
1033 
sanitizeOT::CmapSubtable1034   bool sanitize (hb_sanitize_context_t *c) const
1035   {
1036     TRACE_SANITIZE (this);
1037     if (!u.format.sanitize (c)) return_trace (false);
1038     switch (u.format) {
1039     case  0: return_trace (u.format0 .sanitize (c));
1040     case  4: return_trace (u.format4 .sanitize (c));
1041     case  6: return_trace (u.format6 .sanitize (c));
1042     case 10: return_trace (u.format10.sanitize (c));
1043     case 12: return_trace (u.format12.sanitize (c));
1044     case 13: return_trace (u.format13.sanitize (c));
1045     case 14: return_trace (u.format14.sanitize (c));
1046     default:return_trace (true);
1047     }
1048   }
1049 
1050   public:
1051   union {
1052   HBUINT16		format;		/* Format identifier */
1053   CmapSubtableFormat0	format0;
1054   CmapSubtableFormat4	format4;
1055   CmapSubtableFormat6	format6;
1056   CmapSubtableFormat10	format10;
1057   CmapSubtableFormat12	format12;
1058   CmapSubtableFormat13	format13;
1059   CmapSubtableFormat14	format14;
1060   } u;
1061   public:
1062   DEFINE_SIZE_UNION (2, format);
1063 };
1064 
1065 
1066 struct EncodingRecord
1067 {
cmpOT::EncodingRecord1068   int cmp (const EncodingRecord &other) const
1069   {
1070     int ret;
1071     ret = platformID.cmp (other.platformID);
1072     if (ret) return ret;
1073     ret = encodingID.cmp (other.encodingID);
1074     if (ret) return ret;
1075     return 0;
1076   }
1077 
sanitizeOT::EncodingRecord1078   bool sanitize (hb_sanitize_context_t *c, const void *base) const
1079   {
1080     TRACE_SANITIZE (this);
1081     return_trace (c->check_struct (this) &&
1082 		  subtable.sanitize (c, base));
1083   }
1084 
1085   template<typename Iterator,
1086 	   hb_requires (hb_is_iterator (Iterator))>
copyOT::EncodingRecord1087   EncodingRecord* copy (hb_serialize_context_t *c,
1088 			Iterator it,
1089 			unsigned format,
1090 			const void *src_base,
1091 			const void *dst_base,
1092 			const hb_subset_plan_t *plan,
1093 			/* INOUT */ unsigned *objidx) const
1094   {
1095     TRACE_SERIALIZE (this);
1096     auto snap = c->snapshot ();
1097     auto *out = c->embed (this);
1098     if (unlikely (!out)) return_trace (nullptr);
1099     out->subtable = 0;
1100 
1101     if (*objidx == 0)
1102     {
1103       CmapSubtable *cmapsubtable = c->push<CmapSubtable> ();
1104       unsigned origin_length = c->length ();
1105       cmapsubtable->serialize (c, it, format, plan, &(src_base+subtable));
1106       if (c->length () - origin_length > 0) *objidx = c->pop_pack ();
1107       else c->pop_discard ();
1108     }
1109 
1110     if (*objidx == 0)
1111     {
1112       c->revert (snap);
1113       return_trace (nullptr);
1114     }
1115 
1116     c->add_link (out->subtable, *objidx, dst_base);
1117     return_trace (out);
1118   }
1119 
1120   HBUINT16	platformID;	/* Platform ID. */
1121   HBUINT16	encodingID;	/* Platform-specific encoding ID. */
1122   LOffsetTo<CmapSubtable>
1123 		subtable;	/* Byte offset from beginning of table to the subtable for this encoding. */
1124   public:
1125   DEFINE_SIZE_STATIC (8);
1126 };
1127 
1128 struct cmap
1129 {
1130   static constexpr hb_tag_t tableTag = HB_OT_TAG_cmap;
1131 
1132   template<typename Iterator, typename EncodingRecIter,
1133 	   hb_requires (hb_is_iterator (Iterator))>
serializeOT::cmap1134   void serialize (hb_serialize_context_t *c,
1135 		  Iterator it,
1136 		  EncodingRecIter encodingrec_iter,
1137 		  const void *src_base,
1138 		  const hb_subset_plan_t *plan)
1139   {
1140     if (unlikely (!c->extend_min ((*this))))  return;
1141     this->version = 0;
1142 
1143     unsigned format4objidx = 0, format12objidx = 0, format14objidx = 0;
1144 
1145     for (const EncodingRecord& _ : encodingrec_iter)
1146     {
1147       unsigned format = (src_base+_.subtable).u.format;
1148 
1149       if (format == 4) c->copy (_, it, 4u, src_base, this, plan, &format4objidx);
1150       else if (format == 12) c->copy (_, it, 12u, src_base, this, plan, &format12objidx);
1151       else if (format == 14) c->copy (_, it, 14u, src_base, this, plan, &format14objidx);
1152     }
1153 
1154     c->check_assign(this->encodingRecord.len, (c->length () - cmap::min_size)/EncodingRecord::static_size);
1155   }
1156 
closure_glyphsOT::cmap1157   void closure_glyphs (const hb_set_t      *unicodes,
1158 		       hb_set_t            *glyphset) const
1159   {
1160     + hb_iter (encodingRecord)
1161     | hb_map (&EncodingRecord::subtable)
1162     | hb_map (hb_add (this))
1163     | hb_filter ([&] (const CmapSubtable& _) { return _.u.format == 14; })
1164     | hb_apply ([=] (const CmapSubtable& _) { _.u.format14.closure_glyphs (unicodes, glyphset); })
1165     ;
1166   }
1167 
subsetOT::cmap1168   bool subset (hb_subset_context_t *c) const
1169   {
1170     TRACE_SUBSET (this);
1171 
1172     cmap *cmap_prime = c->serializer->start_embed<cmap> ();
1173     if (unlikely (!c->serializer->check_success (cmap_prime))) return_trace (false);
1174 
1175     auto encodingrec_iter =
1176     + hb_iter (encodingRecord)
1177     | hb_filter ([&] (const EncodingRecord& _)
1178 		{
1179 		  if ((_.platformID == 0 && _.encodingID == 3) ||
1180 		      (_.platformID == 0 && _.encodingID == 4) ||
1181 		      (_.platformID == 3 && _.encodingID == 1) ||
1182 		      (_.platformID == 3 && _.encodingID == 10) ||
1183 		      (this + _.subtable).u.format == 14)
1184 		    return true;
1185 
1186 		  return false;
1187 		})
1188     ;
1189 
1190 
1191     if (unlikely (!encodingrec_iter.len ())) return_trace (false);
1192 
1193     const EncodingRecord *unicode_bmp= nullptr, *unicode_ucs4 = nullptr, *ms_bmp = nullptr, *ms_ucs4 = nullptr;
1194     bool has_format12 = false;
1195 
1196     for (const EncodingRecord& _ : encodingrec_iter)
1197     {
1198       unsigned format = (this + _.subtable).u.format;
1199       if (format == 12) has_format12 = true;
1200 
1201       const EncodingRecord *table = hb_addressof (_);
1202       if      (_.platformID == 0 && _.encodingID ==  3) unicode_bmp = table;
1203       else if (_.platformID == 0 && _.encodingID ==  4) unicode_ucs4 = table;
1204       else if (_.platformID == 3 && _.encodingID ==  1) ms_bmp = table;
1205       else if (_.platformID == 3 && _.encodingID == 10) ms_ucs4 = table;
1206     }
1207 
1208     if (unlikely (!unicode_bmp && !ms_bmp)) return_trace (false);
1209     if (unlikely (has_format12 && (!unicode_ucs4 && !ms_ucs4))) return_trace (false);
1210 
1211     auto it =
1212     + hb_iter (c->plan->unicodes)
1213     | hb_map ([&] (hb_codepoint_t _)
1214 	      {
1215 		hb_codepoint_t new_gid = HB_MAP_VALUE_INVALID;
1216 		c->plan->new_gid_for_codepoint (_, &new_gid);
1217 		return hb_pair_t<hb_codepoint_t, hb_codepoint_t> (_, new_gid);
1218 	      })
1219     | hb_filter ([&] (const hb_pair_t<hb_codepoint_t, hb_codepoint_t> _)
1220 		 { return (_.second != HB_MAP_VALUE_INVALID); })
1221     ;
1222 
1223     cmap_prime->serialize (c->serializer, it, encodingrec_iter, this, c->plan);
1224     return_trace (true);
1225   }
1226 
find_best_subtableOT::cmap1227   const CmapSubtable *find_best_subtable (bool *symbol = nullptr) const
1228   {
1229     if (symbol) *symbol = false;
1230 
1231     const CmapSubtable *subtable;
1232 
1233     /* Symbol subtable.
1234      * Prefer symbol if available.
1235      * https://github.com/harfbuzz/harfbuzz/issues/1918 */
1236     if ((subtable = this->find_subtable (3, 0)))
1237     {
1238       if (symbol) *symbol = true;
1239       return subtable;
1240     }
1241 
1242     /* 32-bit subtables. */
1243     if ((subtable = this->find_subtable (3, 10))) return subtable;
1244     if ((subtable = this->find_subtable (0, 6))) return subtable;
1245     if ((subtable = this->find_subtable (0, 4))) return subtable;
1246 
1247     /* 16-bit subtables. */
1248     if ((subtable = this->find_subtable (3, 1))) return subtable;
1249     if ((subtable = this->find_subtable (0, 3))) return subtable;
1250     if ((subtable = this->find_subtable (0, 2))) return subtable;
1251     if ((subtable = this->find_subtable (0, 1))) return subtable;
1252     if ((subtable = this->find_subtable (0, 0))) return subtable;
1253 
1254     /* Meh. */
1255     return &Null (CmapSubtable);
1256   }
1257 
1258   struct accelerator_t
1259   {
initOT::cmap::accelerator_t1260     void init (hb_face_t *face)
1261     {
1262       this->table = hb_sanitize_context_t ().reference_table<cmap> (face);
1263       bool symbol;
1264       this->subtable = table->find_best_subtable (&symbol);
1265       this->subtable_uvs = &Null (CmapSubtableFormat14);
1266       {
1267 	const CmapSubtable *st = table->find_subtable (0, 5);
1268 	if (st && st->u.format == 14)
1269 	  subtable_uvs = &st->u.format14;
1270       }
1271 
1272       this->get_glyph_data = subtable;
1273       if (unlikely (symbol))
1274 	this->get_glyph_funcZ = get_glyph_from_symbol<CmapSubtable>;
1275       else
1276       {
1277 	switch (subtable->u.format) {
1278 	/* Accelerate format 4 and format 12. */
1279 	default:
1280 	  this->get_glyph_funcZ = get_glyph_from<CmapSubtable>;
1281 	  break;
1282 	case 12:
1283 	  this->get_glyph_funcZ = get_glyph_from<CmapSubtableFormat12>;
1284 	  break;
1285 	case  4:
1286 	{
1287 	  this->format4_accel.init (&subtable->u.format4);
1288 	  this->get_glyph_data = &this->format4_accel;
1289 	  this->get_glyph_funcZ = this->format4_accel.get_glyph_func;
1290 	  break;
1291 	}
1292 	}
1293       }
1294     }
1295 
finiOT::cmap::accelerator_t1296     void fini () { this->table.destroy (); }
1297 
get_nominal_glyphOT::cmap::accelerator_t1298     bool get_nominal_glyph (hb_codepoint_t  unicode,
1299 			    hb_codepoint_t *glyph) const
1300     {
1301       if (unlikely (!this->get_glyph_funcZ)) return false;
1302       return this->get_glyph_funcZ (this->get_glyph_data, unicode, glyph);
1303     }
get_nominal_glyphsOT::cmap::accelerator_t1304     unsigned int get_nominal_glyphs (unsigned int count,
1305 				     const hb_codepoint_t *first_unicode,
1306 				     unsigned int unicode_stride,
1307 				     hb_codepoint_t *first_glyph,
1308 				     unsigned int glyph_stride) const
1309     {
1310       if (unlikely (!this->get_glyph_funcZ)) return 0;
1311 
1312       hb_cmap_get_glyph_func_t get_glyph_funcZ = this->get_glyph_funcZ;
1313       const void *get_glyph_data = this->get_glyph_data;
1314 
1315       unsigned int done;
1316       for (done = 0;
1317 	   done < count && get_glyph_funcZ (get_glyph_data, *first_unicode, first_glyph);
1318 	   done++)
1319       {
1320 	first_unicode = &StructAtOffsetUnaligned<hb_codepoint_t> (first_unicode, unicode_stride);
1321 	first_glyph = &StructAtOffsetUnaligned<hb_codepoint_t> (first_glyph, glyph_stride);
1322       }
1323       return done;
1324     }
1325 
get_variation_glyphOT::cmap::accelerator_t1326     bool get_variation_glyph (hb_codepoint_t  unicode,
1327 			      hb_codepoint_t  variation_selector,
1328 			      hb_codepoint_t *glyph) const
1329     {
1330       switch (this->subtable_uvs->get_glyph_variant (unicode,
1331 						     variation_selector,
1332 						     glyph))
1333       {
1334 	case GLYPH_VARIANT_NOT_FOUND:	return false;
1335 	case GLYPH_VARIANT_FOUND:	return true;
1336 	case GLYPH_VARIANT_USE_DEFAULT:	break;
1337       }
1338 
1339       return get_nominal_glyph (unicode, glyph);
1340     }
1341 
collect_unicodesOT::cmap::accelerator_t1342     void collect_unicodes (hb_set_t *out) const
1343     { subtable->collect_unicodes (out); }
collect_variation_selectorsOT::cmap::accelerator_t1344     void collect_variation_selectors (hb_set_t *out) const
1345     { subtable_uvs->collect_variation_selectors (out); }
collect_variation_unicodesOT::cmap::accelerator_t1346     void collect_variation_unicodes (hb_codepoint_t variation_selector,
1347 				     hb_set_t *out) const
1348     { subtable_uvs->collect_variation_unicodes (variation_selector, out); }
1349 
1350     protected:
1351     typedef bool (*hb_cmap_get_glyph_func_t) (const void *obj,
1352 					      hb_codepoint_t codepoint,
1353 					      hb_codepoint_t *glyph);
1354 
1355     template <typename Type>
get_glyph_fromOT::cmap::accelerator_t1356     HB_INTERNAL static bool get_glyph_from (const void *obj,
1357 					    hb_codepoint_t codepoint,
1358 					    hb_codepoint_t *glyph)
1359     {
1360       const Type *typed_obj = (const Type *) obj;
1361       return typed_obj->get_glyph (codepoint, glyph);
1362     }
1363 
1364     template <typename Type>
get_glyph_from_symbolOT::cmap::accelerator_t1365     HB_INTERNAL static bool get_glyph_from_symbol (const void *obj,
1366 						   hb_codepoint_t codepoint,
1367 						   hb_codepoint_t *glyph)
1368     {
1369       const Type *typed_obj = (const Type *) obj;
1370       if (likely (typed_obj->get_glyph (codepoint, glyph)))
1371 	return true;
1372 
1373       if (codepoint <= 0x00FFu)
1374       {
1375 	/* For symbol-encoded OpenType fonts, we duplicate the
1376 	 * U+F000..F0FF range at U+0000..U+00FF.  That's what
1377 	 * Windows seems to do, and that's hinted about at:
1378 	 * https://docs.microsoft.com/en-us/typography/opentype/spec/recom
1379 	 * under "Non-Standard (Symbol) Fonts". */
1380 	return typed_obj->get_glyph (0xF000u + codepoint, glyph);
1381       }
1382 
1383       return false;
1384     }
1385 
1386     private:
1387     hb_nonnull_ptr_t<const CmapSubtable> subtable;
1388     hb_nonnull_ptr_t<const CmapSubtableFormat14> subtable_uvs;
1389 
1390     hb_cmap_get_glyph_func_t get_glyph_funcZ;
1391     const void *get_glyph_data;
1392 
1393     CmapSubtableFormat4::accelerator_t format4_accel;
1394 
1395     public:
1396     hb_blob_ptr_t<cmap> table;
1397   };
1398 
1399   protected:
1400 
find_subtableOT::cmap1401   const CmapSubtable *find_subtable (unsigned int platform_id,
1402 				     unsigned int encoding_id) const
1403   {
1404     EncodingRecord key;
1405     key.platformID = platform_id;
1406     key.encodingID = encoding_id;
1407 
1408     const EncodingRecord &result = encodingRecord.bsearch (key);
1409     if (!result.subtable)
1410       return nullptr;
1411 
1412     return &(this+result.subtable);
1413   }
1414 
find_encodingrecOT::cmap1415   const EncodingRecord *find_encodingrec (unsigned int platform_id,
1416 				    unsigned int encoding_id) const
1417   {
1418     EncodingRecord key;
1419     key.platformID = platform_id;
1420     key.encodingID = encoding_id;
1421 
1422     return encodingRecord.as_array ().bsearch (key);
1423   }
1424 
find_subtableOT::cmap1425   bool find_subtable (unsigned format) const
1426   {
1427     auto it =
1428     + hb_iter (encodingRecord)
1429     | hb_map (&EncodingRecord::subtable)
1430     | hb_map (hb_add (this))
1431     | hb_filter ([&] (const CmapSubtable& _) { return _.u.format == format; })
1432     ;
1433 
1434     return it.len ();
1435   }
1436 
1437   public:
1438 
sanitizeOT::cmap1439   bool sanitize (hb_sanitize_context_t *c) const
1440   {
1441     TRACE_SANITIZE (this);
1442     return_trace (c->check_struct (this) &&
1443 		  likely (version == 0) &&
1444 		  encodingRecord.sanitize (c, this));
1445   }
1446 
1447   protected:
1448   HBUINT16		version;	/* Table version number (0). */
1449   SortedArrayOf<EncodingRecord>
1450 			encodingRecord;	/* Encoding tables. */
1451   public:
1452   DEFINE_SIZE_ARRAY (4, encodingRecord);
1453 };
1454 
1455 struct cmap_accelerator_t : cmap::accelerator_t {};
1456 
1457 } /* namespace OT */
1458 
1459 
1460 #endif /* HB_OT_CMAP_TABLE_HH */
1461