1/*
2 * Copyright © 2007,2008,2009 Red Hat, Inc.
3 * Copyright © 2012 Google, Inc.
4 *
5 * This is part of HarfBuzz, a text shaping library.
6 *
7 * Permission is hereby granted, without written agreement and without
8 * license or royalty fees, to use, copy, modify, and distribute this
9 * software and its documentation for any purpose, provided that the
10 * above copyright notice and the following two paragraphs appear in
11 * all copies of this software.
12 *
13 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
14 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
15 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
16 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
17 * DAMAGE.
18 *
19 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
20 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
21 * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
22 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
23 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
24 *
25 * Red Hat Author(s): Behdad Esfahbod
26 * Google Author(s): Behdad Esfahbod
27 */
28
29#ifndef HB_OPEN_FILE_HH
30#define HB_OPEN_FILE_HH
31
32#include "hb-open-type.hh"
33#include "hb-ot-head-table.hh"
34
35
36namespace OT {
37
38/*
39 *
40 * The OpenType Font File
41 *
42 */
43
44
45/*
46 * Organization of an OpenType Font
47 */
48
49struct OpenTypeFontFile;
50struct OpenTypeOffsetTable;
51struct TTCHeader;
52
53
54typedef struct TableRecord
55{
56 int cmp (Tag t) const { return -t.cmp (tag); }
57
58 HB_INTERNAL static int cmp (const void *pa, const void *pb)
59 {
60 const TableRecord *a = (const TableRecord *) pa;
61 const TableRecord *b = (const TableRecord *) pb;
62 return b->cmp (a->tag);
63 }
64
65 bool sanitize (hb_sanitize_context_t *c) const
66 {
67 TRACE_SANITIZE (this);
68 return_trace (c->check_struct (this));
69 }
70
71 Tag tag; /* 4-byte identifier. */
72 CheckSum checkSum; /* CheckSum for this table. */
73 Offset32 offset; /* Offset from beginning of TrueType font
74 * file. */
75 HBUINT32 length; /* Length of this table. */
76 public:
77 DEFINE_SIZE_STATIC (16);
78} OpenTypeTable;
79
80typedef struct OpenTypeOffsetTable
81{
82 friend struct OpenTypeFontFile;
83
84 unsigned int get_table_count () const { return tables.len; }
85 const TableRecord& get_table (unsigned int i) const
86 { return tables[i]; }
87 unsigned int get_table_tags (unsigned int start_offset,
88 unsigned int *table_count, /* IN/OUT */
89 hb_tag_t *table_tags /* OUT */) const
90 {
91 if (table_count)
92 {
93 + tables.as_array ().sub_array (start_offset, table_count)
94 | hb_map (&TableRecord::tag)
95 | hb_sink (hb_array (table_tags, *table_count))
96 ;
97 }
98 return tables.len;
99 }
100 bool find_table_index (hb_tag_t tag, unsigned int *table_index) const
101 {
102 Tag t;
103 t = tag;
104 /* Use lfind for small fonts; there are fonts that have unsorted table entries;
105 * those tend to work in other tools, so tolerate them.
106 * https://github.com/harfbuzz/harfbuzz/issues/3065 */
107 if (tables.len < 16)
108 return tables.lfind (t, table_index, HB_NOT_FOUND_STORE, Index::NOT_FOUND_INDEX);
109 else
110 return tables.bfind (t, table_index, HB_NOT_FOUND_STORE, Index::NOT_FOUND_INDEX);
111 }
112 const TableRecord& get_table_by_tag (hb_tag_t tag) const
113 {
114 unsigned int table_index;
115 find_table_index (tag, &table_index);
116 return get_table (table_index);
117 }
118
119 public:
120
121 template <typename Iterator,
122 hb_requires ((hb_is_source_of<Iterator, hb_pair_t<hb_tag_t, hb_blob_t *>>::value))>
123 bool serialize (hb_serialize_context_t *c,
124 hb_tag_t sfnt_tag,
125 Iterator it)
126 {
127 TRACE_SERIALIZE (this);
128 /* Alloc 12 for the OTHeader. */
129 if (unlikely (!c->extend_min (this))) return_trace (false);
130 /* Write sfntVersion (bytes 0..3). */
131 sfnt_version = sfnt_tag;
132 /* Take space for numTables, searchRange, entrySelector, RangeShift
133 * and the TableRecords themselves. */
134 unsigned num_items = hb_len (it);
135 if (unlikely (!tables.serialize (c, num_items))) return_trace (false);
136
137 const char *dir_end = (const char *) c->head;
138 HBUINT32 *checksum_adjustment = nullptr;
139
140 /* Write OffsetTables, alloc for and write actual table blobs. */
141 unsigned i = 0;
142 for (hb_pair_t<hb_tag_t, hb_blob_t*> entry : it)
143 {
144 hb_blob_t *blob = entry.second;
145 unsigned len = blob->length;
146
147 /* Allocate room for the table and copy it. */
148 char *start = (char *) c->allocate_size<void> (len, false);
149 if (unlikely (!start)) return false;
150
151 TableRecord &rec = tables.arrayZ[i];
152 rec.tag = entry.first;
153 rec.length = len;
154 rec.offset = 0;
155 if (unlikely (!c->check_assign (rec.offset,
156 (unsigned) ((char *) start - (char *) this),
157 HB_SERIALIZE_ERROR_OFFSET_OVERFLOW)))
158 return_trace (false);
159
160 if (likely (len))
161 hb_memcpy (start, blob->data, len);
162
163 /* 4-byte alignment. */
164 c->align (4);
165 const char *end = (const char *) c->head;
166
167 if (entry.first == HB_OT_TAG_head &&
168 (unsigned) (end - start) >= head::static_size)
169 {
170 head *h = (head *) start;
171 checksum_adjustment = &h->checkSumAdjustment;
172 *checksum_adjustment = 0;
173 }
174
175 rec.checkSum.set_for_data (start, end - start);
176 i++;
177 }
178
179 tables.qsort ();
180
181 if (checksum_adjustment)
182 {
183 CheckSum checksum;
184
185 /* The following line is a slower version of the following block. */
186 //checksum.set_for_data (this, (const char *) c->head - (const char *) this);
187 checksum.set_for_data (this, dir_end - (const char *) this);
188 for (unsigned int i = 0; i < num_items; i++)
189 {
190 TableRecord &rec = tables.arrayZ[i];
191 checksum = checksum + rec.checkSum;
192 }
193
194 *checksum_adjustment = 0xB1B0AFBAu - checksum;
195 }
196
197 return_trace (true);
198 }
199
200 bool sanitize (hb_sanitize_context_t *c) const
201 {
202 TRACE_SANITIZE (this);
203 return_trace (c->check_struct (this) && tables.sanitize (c));
204 }
205
206 protected:
207 Tag sfnt_version; /* '\0\001\0\00' if TrueType / 'OTTO' if CFF */
208 BinSearchArrayOf<TableRecord>
209 tables;
210 public:
211 DEFINE_SIZE_ARRAY (12, tables);
212} OpenTypeFontFace;
213
214
215/*
216 * TrueType Collections
217 */
218
219struct TTCHeaderVersion1
220{
221 friend struct TTCHeader;
222
223 unsigned int get_face_count () const { return table.len; }
224 const OpenTypeFontFace& get_face (unsigned int i) const { return this+table[i]; }
225
226 bool sanitize (hb_sanitize_context_t *c) const
227 {
228 TRACE_SANITIZE (this);
229 return_trace (table.sanitize (c, this));
230 }
231
232 protected:
233 Tag ttcTag; /* TrueType Collection ID string: 'ttcf' */
234 FixedVersion<>version; /* Version of the TTC Header (1.0),
235 * 0x00010000u */
236 Array32Of<Offset32To<OpenTypeOffsetTable>>
237 table; /* Array of offsets to the OffsetTable for each font
238 * from the beginning of the file */
239 public:
240 DEFINE_SIZE_ARRAY (12, table);
241};
242
243struct TTCHeader
244{
245 friend struct OpenTypeFontFile;
246
247 private:
248
249 unsigned int get_face_count () const
250 {
251 switch (u.header.version.major) {
252 case 2: /* version 2 is compatible with version 1 */
253 case 1: return u.version1.get_face_count ();
254 default:return 0;
255 }
256 }
257 const OpenTypeFontFace& get_face (unsigned int i) const
258 {
259 switch (u.header.version.major) {
260 case 2: /* version 2 is compatible with version 1 */
261 case 1: return u.version1.get_face (i);
262 default:return Null (OpenTypeFontFace);
263 }
264 }
265
266 bool sanitize (hb_sanitize_context_t *c) const
267 {
268 TRACE_SANITIZE (this);
269 if (unlikely (!u.header.version.sanitize (c))) return_trace (false);
270 switch (u.header.version.major) {
271 case 2: /* version 2 is compatible with version 1 */
272 case 1: return_trace (u.version1.sanitize (c));
273 default:return_trace (true);
274 }
275 }
276
277 protected:
278 union {
279 struct {
280 Tag ttcTag; /* TrueType Collection ID string: 'ttcf' */
281 FixedVersion<>version; /* Version of the TTC Header (1.0 or 2.0),
282 * 0x00010000u or 0x00020000u */
283 } header;
284 TTCHeaderVersion1 version1;
285 } u;
286};
287
288/*
289 * Mac Resource Fork
290 *
291 * http://mirror.informatimago.com/next/developer.apple.com/documentation/mac/MoreToolbox/MoreToolbox-99.html
292 */
293
294struct ResourceRecord
295{
296 const OpenTypeFontFace & get_face (const void *data_base) const
297 { return * reinterpret_cast<const OpenTypeFontFace *> ((data_base+offset).arrayZ); }
298
299 bool sanitize (hb_sanitize_context_t *c,
300 const void *data_base) const
301 {
302 TRACE_SANITIZE (this);
303 return_trace (c->check_struct (this) &&
304 offset.sanitize (c, data_base) &&
305 get_face (data_base).sanitize (c));
306 }
307
308 protected:
309 HBUINT16 id; /* Resource ID. */
310 HBINT16 nameOffset; /* Offset from beginning of resource name list
311 * to resource name, -1 means there is none. */
312 HBUINT8 attrs; /* Resource attributes */
313 NNOffset24To<Array32Of<HBUINT8>>
314 offset; /* Offset from beginning of data block to
315 * data for this resource */
316 HBUINT32 reserved; /* Reserved for handle to resource */
317 public:
318 DEFINE_SIZE_STATIC (12);
319};
320
321#define HB_TAG_sfnt HB_TAG ('s','f','n','t')
322
323struct ResourceTypeRecord
324{
325 unsigned int get_resource_count () const
326 { return tag == HB_TAG_sfnt ? resCountM1 + 1 : 0; }
327
328 bool is_sfnt () const { return tag == HB_TAG_sfnt; }
329
330 const ResourceRecord& get_resource_record (unsigned int i,
331 const void *type_base) const
332 { return (type_base+resourcesZ).as_array (get_resource_count ())[i]; }
333
334 bool sanitize (hb_sanitize_context_t *c,
335 const void *type_base,
336 const void *data_base) const
337 {
338 TRACE_SANITIZE (this);
339 return_trace (c->check_struct (this) &&
340 resourcesZ.sanitize (c, type_base,
341 get_resource_count (),
342 data_base));
343 }
344
345 protected:
346 Tag tag; /* Resource type. */
347 HBUINT16 resCountM1; /* Number of resources minus 1. */
348 NNOffset16To<UnsizedArrayOf<ResourceRecord>>
349 resourcesZ; /* Offset from beginning of resource type list
350 * to reference item list for this type. */
351 public:
352 DEFINE_SIZE_STATIC (8);
353};
354
355struct ResourceMap
356{
357 unsigned int get_face_count () const
358 {
359 unsigned int count = get_type_count ();
360 for (unsigned int i = 0; i < count; i++)
361 {
362 const ResourceTypeRecord& type = get_type_record (i);
363 if (type.is_sfnt ())
364 return type.get_resource_count ();
365 }
366 return 0;
367 }
368
369 const OpenTypeFontFace& get_face (unsigned int idx,
370 const void *data_base) const
371 {
372 unsigned int count = get_type_count ();
373 for (unsigned int i = 0; i < count; i++)
374 {
375 const ResourceTypeRecord& type = get_type_record (i);
376 /* The check for idx < count is here because ResourceRecord is NOT null-safe.
377 * Because an offset of 0 there does NOT mean null. */
378 if (type.is_sfnt () && idx < type.get_resource_count ())
379 return type.get_resource_record (idx, &(this+typeList)).get_face (data_base);
380 }
381 return Null (OpenTypeFontFace);
382 }
383
384 bool sanitize (hb_sanitize_context_t *c, const void *data_base) const
385 {
386 TRACE_SANITIZE (this);
387 return_trace (c->check_struct (this) &&
388 typeList.sanitize (c, this,
389 &(this+typeList),
390 data_base));
391 }
392
393 private:
394 unsigned int get_type_count () const { return (this+typeList).lenM1 + 1; }
395
396 const ResourceTypeRecord& get_type_record (unsigned int i) const
397 { return (this+typeList)[i]; }
398
399 protected:
400 HBUINT8 reserved0[16]; /* Reserved for copy of resource header */
401 HBUINT32 reserved1; /* Reserved for handle to next resource map */
402 HBUINT16 resreved2; /* Reserved for file reference number */
403 HBUINT16 attrs; /* Resource fork attribute */
404 NNOffset16To<ArrayOfM1<ResourceTypeRecord>>
405 typeList; /* Offset from beginning of map to
406 * resource type list */
407 Offset16 nameList; /* Offset from beginning of map to
408 * resource name list */
409 public:
410 DEFINE_SIZE_STATIC (28);
411};
412
413struct ResourceForkHeader
414{
415 unsigned int get_face_count () const
416 { return (this+map).get_face_count (); }
417
418 const OpenTypeFontFace& get_face (unsigned int idx,
419 unsigned int *base_offset = nullptr) const
420 {
421 const OpenTypeFontFace &face = (this+map).get_face (idx, &(this+data));
422 if (base_offset)
423 *base_offset = (const char *) &face - (const char *) this;
424 return face;
425 }
426
427 bool sanitize (hb_sanitize_context_t *c) const
428 {
429 TRACE_SANITIZE (this);
430 return_trace (c->check_struct (this) &&
431 data.sanitize (c, this, dataLen) &&
432 map.sanitize (c, this, &(this+data)));
433 }
434
435 protected:
436 NNOffset32To<UnsizedArrayOf<HBUINT8>>
437 data; /* Offset from beginning of resource fork
438 * to resource data */
439 NNOffset32To<ResourceMap >
440 map; /* Offset from beginning of resource fork
441 * to resource map */
442 HBUINT32 dataLen; /* Length of resource data */
443 HBUINT32 mapLen; /* Length of resource map */
444 public:
445 DEFINE_SIZE_STATIC (16);
446};
447
448/*
449 * OpenType Font File
450 */
451
452struct OpenTypeFontFile
453{
454 enum {
455 CFFTag = HB_TAG ('O','T','T','O'), /* OpenType with Postscript outlines */
456 TrueTypeTag = HB_TAG ( 0 , 1 , 0 , 0 ), /* OpenType with TrueType outlines */
457 TTCTag = HB_TAG ('t','t','c','f'), /* TrueType Collection */
458 DFontTag = HB_TAG ( 0 , 0 , 1 , 0 ), /* DFont Mac Resource Fork */
459 TrueTag = HB_TAG ('t','r','u','e'), /* Obsolete Apple TrueType */
460 Typ1Tag = HB_TAG ('t','y','p','1') /* Obsolete Apple Type1 font in SFNT container */
461 };
462
463 hb_tag_t get_tag () const { return u.tag; }
464
465 unsigned int get_face_count () const
466 {
467 switch (u.tag) {
468 case CFFTag: /* All the non-collection tags */
469 case TrueTag:
470 case Typ1Tag:
471 case TrueTypeTag: return 1;
472 case TTCTag: return u.ttcHeader.get_face_count ();
473 case DFontTag: return u.rfHeader.get_face_count ();
474 default: return 0;
475 }
476 }
477 const OpenTypeFontFace& get_face (unsigned int i, unsigned int *base_offset = nullptr) const
478 {
479 if (base_offset)
480 *base_offset = 0;
481 switch (u.tag) {
482 /* Note: for non-collection SFNT data we ignore index. This is because
483 * Apple dfont container is a container of SFNT's. So each SFNT is a
484 * non-TTC, but the index is more than zero. */
485 case CFFTag: /* All the non-collection tags */
486 case TrueTag:
487 case Typ1Tag:
488 case TrueTypeTag: return u.fontFace;
489 case TTCTag: return u.ttcHeader.get_face (i);
490 case DFontTag: return u.rfHeader.get_face (i, base_offset);
491 default: return Null (OpenTypeFontFace);
492 }
493 }
494
495 template <typename Iterator,
496 hb_requires ((hb_is_source_of<Iterator, hb_pair_t<hb_tag_t, hb_blob_t *>>::value))>
497 bool serialize_single (hb_serialize_context_t *c,
498 hb_tag_t sfnt_tag,
499 Iterator items)
500 {
501 TRACE_SERIALIZE (this);
502 assert (sfnt_tag != TTCTag);
503 if (unlikely (!c->extend_min (this))) return_trace (false);
504 return_trace (u.fontFace.serialize (c, sfnt_tag, items));
505 }
506
507 bool sanitize (hb_sanitize_context_t *c) const
508 {
509 TRACE_SANITIZE (this);
510 if (unlikely (!u.tag.sanitize (c))) return_trace (false);
511 switch (u.tag) {
512 case CFFTag: /* All the non-collection tags */
513 case TrueTag:
514 case Typ1Tag:
515 case TrueTypeTag: return_trace (u.fontFace.sanitize (c));
516 case TTCTag: return_trace (u.ttcHeader.sanitize (c));
517 case DFontTag: return_trace (u.rfHeader.sanitize (c));
518 default: return_trace (true);
519 }
520 }
521
522 protected:
523 union {
524 Tag tag; /* 4-byte identifier. */
525 OpenTypeFontFace fontFace;
526 TTCHeader ttcHeader;
527 ResourceForkHeader rfHeader;
528 } u;
529 public:
530 DEFINE_SIZE_UNION (4, tag);
531};
532
533
534} /* namespace OT */
535
536
537#endif /* HB_OPEN_FILE_HH */
538