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 *
41 * The OpenType Font File
42 *
43 */
44
45
46/*
47 * Organization of an OpenType Font
48 */
49
50struct OpenTypeFontFile;
51struct OffsetTable;
52struct TTCHeader;
53
54
55typedef struct TableRecord
56{
57 int cmp (Tag t) const { return -t.cmp (tag); }
58
59 HB_INTERNAL static int cmp (const void *pa, const void *pb)
60 {
61 const TableRecord *a = (const TableRecord *) pa;
62 const TableRecord *b = (const TableRecord *) pb;
63 return b->cmp (a->tag);
64 }
65
66 bool sanitize (hb_sanitize_context_t *c) const
67 {
68 TRACE_SANITIZE (this);
69 return_trace (c->check_struct (this));
70 }
71
72 Tag tag; /* 4-byte identifier. */
73 CheckSum checkSum; /* CheckSum for this table. */
74 Offset32 offset; /* Offset from beginning of TrueType font
75 * file. */
76 HBUINT32 length; /* Length of this table. */
77 public:
78 DEFINE_SIZE_STATIC (16);
79} OpenTypeTable;
80
81typedef struct OffsetTable
82{
83 friend struct OpenTypeFontFile;
84
85 unsigned int get_table_count () const { return tables.len; }
86 const TableRecord& get_table (unsigned int i) const
87 { return tables[i]; }
88 unsigned int get_table_tags (unsigned int start_offset,
89 unsigned int *table_count, /* IN/OUT */
90 hb_tag_t *table_tags /* OUT */) const
91 {
92 if (table_count)
93 {
94 + tables.sub_array (start_offset, table_count)
95 | hb_map (&TableRecord::tag)
96 | hb_sink (hb_array (table_tags, *table_count))
97 ;
98 }
99 return tables.len;
100 }
101 bool find_table_index (hb_tag_t tag, unsigned int *table_index) const
102 {
103 Tag t;
104 t = tag;
105 return tables.bfind (t, table_index, HB_BFIND_NOT_FOUND_STORE, Index::NOT_FOUND_INDEX);
106 }
107 const TableRecord& get_table_by_tag (hb_tag_t tag) const
108 {
109 unsigned int table_index;
110 find_table_index (tag, &table_index);
111 return get_table (table_index);
112 }
113
114 public:
115
116 template <typename item_t>
117 bool serialize (hb_serialize_context_t *c,
118 hb_tag_t sfnt_tag,
119 hb_array_t<item_t> items)
120 {
121 TRACE_SERIALIZE (this);
122 /* Alloc 12 for the OTHeader. */
123 if (unlikely (!c->extend_min (*this))) return_trace (false);
124 /* Write sfntVersion (bytes 0..3). */
125 sfnt_version = sfnt_tag;
126 /* Take space for numTables, searchRange, entrySelector, RangeShift
127 * and the TableRecords themselves. */
128 if (unlikely (!tables.serialize (c, items.length))) return_trace (false);
129
130 const char *dir_end = (const char *) c->head;
131 HBUINT32 *checksum_adjustment = nullptr;
132
133 /* Write OffsetTables, alloc for and write actual table blobs. */
134 for (unsigned int i = 0; i < tables.len; i++)
135 {
136 TableRecord &rec = tables.arrayZ[i];
137 hb_blob_t *blob = items[i].blob;
138 rec.tag = items[i].tag;
139 rec.length = blob->length;
140 rec.offset.serialize (c, this);
141
142 /* Allocate room for the table and copy it. */
143 char *start = (char *) c->allocate_size<void> (rec.length);
144 if (unlikely (!start)) return false;
145
146 if (likely (rec.length))
147 memcpy (start, blob->data, rec.length);
148
149 /* 4-byte alignment. */
150 c->align (4);
151 const char *end = (const char *) c->head;
152
153 if (items[i].tag == HB_OT_TAG_head &&
154 (unsigned) (end - start) >= head::static_size)
155 {
156 head *h = (head *) start;
157 checksum_adjustment = &h->checkSumAdjustment;
158 *checksum_adjustment = 0;
159 }
160
161 rec.checkSum.set_for_data (start, end - start);
162 }
163
164 tables.qsort ();
165
166 if (checksum_adjustment)
167 {
168 CheckSum checksum;
169
170 /* The following line is a slower version of the following block. */
171 //checksum.set_for_data (this, (const char *) c->head - (const char *) this);
172 checksum.set_for_data (this, dir_end - (const char *) this);
173 for (unsigned int i = 0; i < items.length; i++)
174 {
175 TableRecord &rec = tables.arrayZ[i];
176 checksum = checksum + rec.checkSum;
177 }
178
179 *checksum_adjustment = 0xB1B0AFBAu - checksum;
180 }
181
182 return_trace (true);
183 }
184
185 bool sanitize (hb_sanitize_context_t *c) const
186 {
187 TRACE_SANITIZE (this);
188 return_trace (c->check_struct (this) && tables.sanitize (c));
189 }
190
191 protected:
192 Tag sfnt_version; /* '\0\001\0\00' if TrueType / 'OTTO' if CFF */
193 BinSearchArrayOf<TableRecord>
194 tables;
195 public:
196 DEFINE_SIZE_ARRAY (12, tables);
197} OpenTypeFontFace;
198
199
200/*
201 * TrueType Collections
202 */
203
204struct TTCHeaderVersion1
205{
206 friend struct TTCHeader;
207
208 unsigned int get_face_count () const { return table.len; }
209 const OpenTypeFontFace& get_face (unsigned int i) const { return this+table[i]; }
210
211 bool sanitize (hb_sanitize_context_t *c) const
212 {
213 TRACE_SANITIZE (this);
214 return_trace (table.sanitize (c, this));
215 }
216
217 protected:
218 Tag ttcTag; /* TrueType Collection ID string: 'ttcf' */
219 FixedVersion<>version; /* Version of the TTC Header (1.0),
220 * 0x00010000u */
221 LArrayOf<LOffsetTo<OffsetTable>>
222 table; /* Array of offsets to the OffsetTable for each font
223 * from the beginning of the file */
224 public:
225 DEFINE_SIZE_ARRAY (12, table);
226};
227
228struct TTCHeader
229{
230 friend struct OpenTypeFontFile;
231
232 private:
233
234 unsigned int get_face_count () const
235 {
236 switch (u.header.version.major) {
237 case 2: /* version 2 is compatible with version 1 */
238 case 1: return u.version1.get_face_count ();
239 default:return 0;
240 }
241 }
242 const OpenTypeFontFace& get_face (unsigned int i) const
243 {
244 switch (u.header.version.major) {
245 case 2: /* version 2 is compatible with version 1 */
246 case 1: return u.version1.get_face (i);
247 default:return Null (OpenTypeFontFace);
248 }
249 }
250
251 bool sanitize (hb_sanitize_context_t *c) const
252 {
253 TRACE_SANITIZE (this);
254 if (unlikely (!u.header.version.sanitize (c))) return_trace (false);
255 switch (u.header.version.major) {
256 case 2: /* version 2 is compatible with version 1 */
257 case 1: return_trace (u.version1.sanitize (c));
258 default:return_trace (true);
259 }
260 }
261
262 protected:
263 union {
264 struct {
265 Tag ttcTag; /* TrueType Collection ID string: 'ttcf' */
266 FixedVersion<>version; /* Version of the TTC Header (1.0 or 2.0),
267 * 0x00010000u or 0x00020000u */
268 } header;
269 TTCHeaderVersion1 version1;
270 } u;
271};
272
273/*
274 * Mac Resource Fork
275 *
276 * http://mirror.informatimago.com/next/developer.apple.com/documentation/mac/MoreToolbox/MoreToolbox-99.html
277 */
278
279struct ResourceRecord
280{
281 const OpenTypeFontFace & get_face (const void *data_base) const
282 { return * reinterpret_cast<const OpenTypeFontFace *> ((data_base+offset).arrayZ); }
283
284 bool sanitize (hb_sanitize_context_t *c,
285 const void *data_base) const
286 {
287 TRACE_SANITIZE (this);
288 return_trace (c->check_struct (this) &&
289 offset.sanitize (c, data_base) &&
290 get_face (data_base).sanitize (c));
291 }
292
293 protected:
294 HBUINT16 id; /* Resource ID. */
295 HBINT16 nameOffset; /* Offset from beginning of resource name list
296 * to resource name, -1 means there is none. */
297 HBUINT8 attrs; /* Resource attributes */
298 NNOffsetTo<LArrayOf<HBUINT8>, HBUINT24>
299 offset; /* Offset from beginning of data block to
300 * data for this resource */
301 HBUINT32 reserved; /* Reserved for handle to resource */
302 public:
303 DEFINE_SIZE_STATIC (12);
304};
305
306#define HB_TAG_sfnt HB_TAG ('s','f','n','t')
307
308struct ResourceTypeRecord
309{
310 unsigned int get_resource_count () const
311 { return tag == HB_TAG_sfnt ? resCountM1 + 1 : 0; }
312
313 bool is_sfnt () const { return tag == HB_TAG_sfnt; }
314
315 const ResourceRecord& get_resource_record (unsigned int i,
316 const void *type_base) const
317 { return (type_base+resourcesZ).as_array (get_resource_count ())[i]; }
318
319 bool sanitize (hb_sanitize_context_t *c,
320 const void *type_base,
321 const void *data_base) const
322 {
323 TRACE_SANITIZE (this);
324 return_trace (c->check_struct (this) &&
325 resourcesZ.sanitize (c, type_base,
326 get_resource_count (),
327 data_base));
328 }
329
330 protected:
331 Tag tag; /* Resource type. */
332 HBUINT16 resCountM1; /* Number of resources minus 1. */
333 NNOffsetTo<UnsizedArrayOf<ResourceRecord>>
334 resourcesZ; /* Offset from beginning of resource type list
335 * to reference item list for this type. */
336 public:
337 DEFINE_SIZE_STATIC (8);
338};
339
340struct ResourceMap
341{
342 unsigned int get_face_count () const
343 {
344 unsigned int count = get_type_count ();
345 for (unsigned int i = 0; i < count; i++)
346 {
347 const ResourceTypeRecord& type = get_type_record (i);
348 if (type.is_sfnt ())
349 return type.get_resource_count ();
350 }
351 return 0;
352 }
353
354 const OpenTypeFontFace& get_face (unsigned int idx,
355 const void *data_base) const
356 {
357 unsigned int count = get_type_count ();
358 for (unsigned int i = 0; i < count; i++)
359 {
360 const ResourceTypeRecord& type = get_type_record (i);
361 /* The check for idx < count is here because ResourceRecord is NOT null-safe.
362 * Because an offset of 0 there does NOT mean null. */
363 if (type.is_sfnt () && idx < type.get_resource_count ())
364 return type.get_resource_record (idx, &(this+typeList)).get_face (data_base);
365 }
366 return Null (OpenTypeFontFace);
367 }
368
369 bool sanitize (hb_sanitize_context_t *c, const void *data_base) const
370 {
371 TRACE_SANITIZE (this);
372 return_trace (c->check_struct (this) &&
373 typeList.sanitize (c, this,
374 &(this+typeList),
375 data_base));
376 }
377
378 private:
379 unsigned int get_type_count () const { return (this+typeList).lenM1 + 1; }
380
381 const ResourceTypeRecord& get_type_record (unsigned int i) const
382 { return (this+typeList)[i]; }
383
384 protected:
385 HBUINT8 reserved0[16]; /* Reserved for copy of resource header */
386 HBUINT32 reserved1; /* Reserved for handle to next resource map */
387 HBUINT16 resreved2; /* Reserved for file reference number */
388 HBUINT16 attrs; /* Resource fork attribute */
389 NNOffsetTo<ArrayOfM1<ResourceTypeRecord>>
390 typeList; /* Offset from beginning of map to
391 * resource type list */
392 Offset16 nameList; /* Offset from beginning of map to
393 * resource name list */
394 public:
395 DEFINE_SIZE_STATIC (28);
396};
397
398struct ResourceForkHeader
399{
400 unsigned int get_face_count () const
401 { return (this+map).get_face_count (); }
402
403 const OpenTypeFontFace& get_face (unsigned int idx,
404 unsigned int *base_offset = nullptr) const
405 {
406 const OpenTypeFontFace &face = (this+map).get_face (idx, &(this+data));
407 if (base_offset)
408 *base_offset = (const char *) &face - (const char *) this;
409 return face;
410 }
411
412 bool sanitize (hb_sanitize_context_t *c) const
413 {
414 TRACE_SANITIZE (this);
415 return_trace (c->check_struct (this) &&
416 data.sanitize (c, this, dataLen) &&
417 map.sanitize (c, this, &(this+data)));
418 }
419
420 protected:
421 LNNOffsetTo<UnsizedArrayOf<HBUINT8>>
422 data; /* Offset from beginning of resource fork
423 * to resource data */
424 LNNOffsetTo<ResourceMap >
425 map; /* Offset from beginning of resource fork
426 * to resource map */
427 HBUINT32 dataLen; /* Length of resource data */
428 HBUINT32 mapLen; /* Length of resource map */
429 public:
430 DEFINE_SIZE_STATIC (16);
431};
432
433/*
434 * OpenType Font File
435 */
436
437struct OpenTypeFontFile
438{
439 enum {
440 CFFTag = HB_TAG ('O','T','T','O'), /* OpenType with Postscript outlines */
441 TrueTypeTag = HB_TAG ( 0 , 1 , 0 , 0 ), /* OpenType with TrueType outlines */
442 TTCTag = HB_TAG ('t','t','c','f'), /* TrueType Collection */
443 DFontTag = HB_TAG ( 0 , 0 , 1 , 0 ), /* DFont Mac Resource Fork */
444 TrueTag = HB_TAG ('t','r','u','e'), /* Obsolete Apple TrueType */
445 Typ1Tag = HB_TAG ('t','y','p','1') /* Obsolete Apple Type1 font in SFNT container */
446 };
447
448 hb_tag_t get_tag () const { return u.tag; }
449
450 unsigned int get_face_count () const
451 {
452 switch (u.tag) {
453 case CFFTag: /* All the non-collection tags */
454 case TrueTag:
455 case Typ1Tag:
456 case TrueTypeTag: return 1;
457 case TTCTag: return u.ttcHeader.get_face_count ();
458 case DFontTag: return u.rfHeader.get_face_count ();
459 default: return 0;
460 }
461 }
462 const OpenTypeFontFace& get_face (unsigned int i, unsigned int *base_offset = nullptr) const
463 {
464 if (base_offset)
465 *base_offset = 0;
466 switch (u.tag) {
467 /* Note: for non-collection SFNT data we ignore index. This is because
468 * Apple dfont container is a container of SFNT's. So each SFNT is a
469 * non-TTC, but the index is more than zero. */
470 case CFFTag: /* All the non-collection tags */
471 case TrueTag:
472 case Typ1Tag:
473 case TrueTypeTag: return u.fontFace;
474 case TTCTag: return u.ttcHeader.get_face (i);
475 case DFontTag: return u.rfHeader.get_face (i, base_offset);
476 default: return Null (OpenTypeFontFace);
477 }
478 }
479
480 template <typename item_t>
481 bool serialize_single (hb_serialize_context_t *c,
482 hb_tag_t sfnt_tag,
483 hb_array_t<item_t> items)
484 {
485 TRACE_SERIALIZE (this);
486 assert (sfnt_tag != TTCTag);
487 if (unlikely (!c->extend_min (*this))) return_trace (false);
488 return_trace (u.fontFace.serialize (c, sfnt_tag, items));
489 }
490
491 bool sanitize (hb_sanitize_context_t *c) const
492 {
493 TRACE_SANITIZE (this);
494 if (unlikely (!u.tag.sanitize (c))) return_trace (false);
495 switch (u.tag) {
496 case CFFTag: /* All the non-collection tags */
497 case TrueTag:
498 case Typ1Tag:
499 case TrueTypeTag: return_trace (u.fontFace.sanitize (c));
500 case TTCTag: return_trace (u.ttcHeader.sanitize (c));
501 case DFontTag: return_trace (u.rfHeader.sanitize (c));
502 default: return_trace (true);
503 }
504 }
505
506 protected:
507 union {
508 Tag tag; /* 4-byte identifier. */
509 OpenTypeFontFace fontFace;
510 TTCHeader ttcHeader;
511 ResourceForkHeader rfHeader;
512 } u;
513 public:
514 DEFINE_SIZE_UNION (4, tag);
515};
516
517
518} /* namespace OT */
519
520
521#endif /* HB_OPEN_FILE_HH */
522